• Journal of Plant Biology
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• v.3 no.2
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• pp.6-18
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• 1960

The present experiments were designed in order to clarify the differences between the long and short styled plants and the transgressive gradition in the degree of dimorphism among the three heterostylous species of the Polygonus, P. japonica, F. esculentum, and P. senticosa, based on investigations regarding the floral structure, ecological and physiological traits, the results of which are summarized as follows: (1) P. japonica, although it exhibits typical dimorphism, has undergone so high a differentiation between long and short styled that its long styled individuals behave as if they were female; and short styled individuals as if male. In long-styled individuals, filament, anther, and pollen grains show signs of degeneration, most of the pollen being abortive. On the other hand, in short styled individuals, the filament, anther, and pollen grains have attained remarkable development; the pollen grians are large and fertile. In short-plant the fertilized flowers readily drop off in every stage of their embryo development. This species has completely lost the self-fertile property, which is characteristic of the non-dimorphic Polygonum genus. Although this specsei typically exhibits the physiological characteristics of the non-dimorphic Polygonum genus. Although this specisei typically exhibits the physiological characteristics of dimorphism in controlled pollination, the short-styled individuals bear no seed in nature, thus misleading taxonomists to idenfity the short-styled plant as male. 2) The morphological feature of the flower organ of P. senticosa obviously indicates definite dimorphism. Physiologically, however, no differentiation towards dimorphism was observed, the species still retaining, both in long and short-individuals, the self-fertile property common to the Polygonum genus. Elaborate examinations revealed that regardless of the modes of pollination, both fertiization and seed setting flourish, no differentiation betwen legitimate and illegitimate unions being recognizable. This sort of physiological property has not been observed in the investigations of other heterostylous plants. It is assumed that this species is differentiated structurally into dimorphism, but not yet physiologically. In nature, however, this plant would have more opportunities to be cross-pollinated, i.e., legitimately combined, than self-pollinated because of the development of two forms of flowers. 3) In terms of heterostylism, the F. esculentum just occupies the intermediate position between P. japonica and P. senticosa structurally, ecologically, and physiologically. Doescription of some of the physiological behavior of the plant will suffice to demonstrate the above facts. While P. japonica has completely lost its self-fertile property, P. senticosa still retains it wolly. In F. esculentum 2-6% of self-fertility is the result in illegitimate combination. There occur occasionally hereditary self fertile individuals among some of the F. or 20 min. irradiation plot, when they reach any stage of the same bacterial population. In addition to this increase of total population in the plots with the more dose of UV light irradiation, it seems that the more dose of UV light irradiation is the more shortened the generation time of Azotobacter. Therefore, it is clear that variation of reproductive rate must be, mere or less, due to the genetic effects induced by UV light irradiation. On the other hand, the lag phase or logarithmic growth phase in nonirradiated culture is shortened prominently, and this must be due to the difference in bacterial number of the original inoculm. The generation time of Azotobacter is shortened by exogeneous treatment of nuclei acid derivatives, and the degree is greater in case of DNA derivatives than RNA dervatives. W.H. Price reported that the rate of ribose nucleic acid to protein in Staphylococcus muscae is proportional to the generation time: that is the faster the cell can form ribose nucleic acid, the more rapid its growth. This explains the shortening of generation time by exogeneous RNA derivatives in this work reasonably. On the other hand, it is well known that the desoxyribose nuclic acid content per cell is constant and independent of the generation time. A.D. Laren and W.N. Takahashi reported that the infectious RNA from TMV is 6 times as sensitive to inactivation by UV as it is in the form of intact virus, and that inactivation of infectious TMV involves onlu a local change on RNA chain. But, the effect of exogeneous DNA in this work suggests that irradiated living cell which cotain DNA bring about some change on DNA moleculs as well as RNA molecules. And if the mutagenic effects of UV take into consideration, it is very reasonable. Therefore, it is clear that the variation of the generation time by UV irradiation is, more or less, due to the genetic effects. Therefore, it seems that the shortness of the average lifewpan of Azotobacter by UV irradiation is resulted not only from the influence of the environmental conditions, but also from the variation of genetic factor of the individual.

• Journal of Embryo Transfer
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• v.30 no.3
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• pp.195-200
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• 2015

The objective of this study was to evaluate the toxicities of permeable cryoprotectants and finally to establish the cryopreservation method of surplus embryos obtained during assisted reproductive technology (ART). Toxicities of permeable cryoprotectants, dimethyl sulfoxide (DMSO), ethylene glycol (EG), Glycerol, and 1,2-PROH were investigated using a murine embryo model. Female $F-{_1}$ mice were stimulated with gonadotropin, induced ovulation with hCG and mated. Two cell embryos were collected and cultured after exposure to among DMSO, EG, Glycerol, and 1,2-PROH. Embryo development was evaluated up to the blastocyst stage. The total cell count of blastocysts that were treated with DMSO and Glycerol at the 2-cell stage was significantly lower than that were treated with EG ($81.1{\pm}15.1$), 1,2-PROH ($88.0{\pm}21.1$) or the control ($99.9{\pm}21.3$) (p<0.001). On comparison of four cryoprotectant treated groups, the DMSO and Glycerol treated group showed a decreased cell count compared with the EG and 1,2-PROH treated group (p<0.05). Both DMSO ($14.7{\pm}1.3$), EG ($12.1{\pm}1.1$), Glycerol ($15.2{\pm}1.8$), and 1,2-PROH ($11.5{\pm}1.3$) treated groups showed higher apoptosis rates of cells in the blastocyst compared with the control ($6.5{\pm}0.7$, p<0.0001). In addition, the DMSO or Glycerol treated group showed more apoptotic cells than the EG or 1,2-PROH treated group (p<0.001). The potential toxicity of cryoprotectants was uncovered by prolonged exposure of murine embryos to among DMSO, EG, Glycerol, and 1,2-PROH at room temperature. When comparing four permeable cryoprotective agents, EG and 1,2-PROH appeared to be less toxic than DMSO and Glycerol at least in a murine embryo model.

• Reproductive and Developmental Biology
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• v.28 no.2
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• pp.77-82
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• 2004

The purpose of this study was performed to establish the in vitro culture system of porcine in vitro maturation and in vitro fertilization(IVM/IVF) embryo. These studies was to determine the effects of antioxidants(aesculetin, taurine and melatonin) in porcine IVM/IVF embryos. In routine porcine IVM/IVF procedure, oocytes were cultured for 40∼44h incubation in NCSU 23 mediumand matured oocytes were inseminated with frozen semen. Then 2 to 8 cell embryos were removed cumulus cell and were allotted randomly to NCSU 23 containing different concentration of antioxidants in 5% $O_2$ and 5% $CO_2$ at 38.5$^{\circ}C$. Cell numbers of blastocyst were also counted using double fluorescence stain method. Aesculetin were added to NCSU 23 medium at concentration of 1 ug, 5 ug, and 10 ug, when treated with 10 ug(35.7%) of aesucletin at the rate of embryos of the morula plus blatocsyts were higher than those of any other groups (30.2%, 29.5% and 29.2%)(P<0.05). The developmental rates beyond morula stage of porcine embryos in NCSU 23 medium supplemented with taurine 0, 2.5 and 5.0 mM were 26.1%, 26.9% and 31.7%, respectively. The addition of 5.0 mM taurine was higher the developmental rate beyond morula stage than in any other groups. In NCSU 23 medium treated with melatonin 0, 1, 5 and 10 nM, the developmental rate of morula plus blastocysts were 33.3%, 39.1%, 33.3% and 27.9%, respectively. The developmental rate of morula and blascytocys treated with 1nM melatonin was higher than in any other groups(P<0.05). Cell numbers of blastocyst in NCSU 23 treated with melatonin 0, 1, 5 and 10nM were 41.0, 42.6, 39.6 and 33.0, respectively. These results indicate that aesculetin, taurine and melation can increase the developmental rate beyond the morulae and blastocysts in porcine embryos.

• Korean Journal of Psychosomatic Medicine
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• v.23 no.1
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• pp.57-65
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• 2015

Objectives:Within the normal reproductive cycles of women, dramatic fluctuations of sexual hormones occur in the premenstrual and menopausal periods. In both periods, women are vulnerable to mood disturbances and show several somatic complaints. Based on these common clinical profiles and physiological changes, a relationship between vasomotor symptoms and the premenstrual syndrome has been suggested. However, attempts to establish such a link have yielded inconclusive results. The purpose of this study was to investigate the association between histories of premenstrual syndrome and menopausal vasomotor symptoms within different menopausal stages. Methods:This cross-sectional study recruited Korean women aged 45-64 years who were perimenopausal and postmenopausal from 16 branch offices of the Korean Association of Health Promotion. All subjects completed self-report questionnaires that asked about a history of premenstrual syndromes, vasomotor symptoms, and several other variables. Results:A total of 1054 participants(361 perimenopausal women and 693 postmenopausal women) completed the study. Severity of premenstrual symptoms significantly correlated with postmenopausal vasomotor symptoms, only in late perimenopausal(r=0.213, p=0.010) and early postmenopausal women(r=0.246, p<0.001). After adjusting for several factors related to vasomotor symptoms, a history of premenstrual syndrome was a significant predictor of moderate to very severe vasomotor symptoms in late perimenopausal(OR=5.197, p=0.005) and early postmenopausal women(OR=3.017, p=0.010). Conclusions:This study suggests that a history of premenstrual syndrome/premenstrual dysphoric disorder is differentially associated with vasomotor symptoms in the menopausal stage. Prospective studies with larger population are needed to confirm these findings

• Korean journal of applied entomology
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• v.57 no.4
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• pp.261-269
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• 2018

The cowpea aphid Aphis craccivora Koch (Hemiptera: Aphididae) is a polyphagous species with a worldwide distribution. We investigated the temperature effects on development periods of nymphs, and the longevity and fecundity of apterous female of A. craccivora. The study was conducted at six constant temperatures of 10.0, 15.0, 20.0, 25, 30.0, and $32.5^{\circ}C$. A. craccivora developed successfully from nymph to adult stage at all temperatures subjected. The developmental rate of A. craccivora increased as temperature increased. The lower developmental threshold (LT) and thermal constant (K) of A. craccivora nymph stage were estimated by linear regression as $5.3^{\circ}C$ and 128.4 degree-days (DD), respectively. Lower and higher threshold temperatures (TL, TH and TH-TL, respectively) were calculated by the Sharpe_Schoolfield_Ikemoto (SSI) model as $17.0^{\circ}C$, $34.6^{\circ}C$ and $17.5^{\circ}C$. Developmental completion of nymph stages was described using a three-parameter Weibull function. Life table parameters were estimated. The intrinsic rate of increase was highest at $25^{\circ}C$, while the net reproductive rate was highest at $20^{\circ}C$. Biological characteristics of A. craccivora populations from different geographic areas were discussed.

• Korean journal of applied entomology
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• v.24 no.3 s.64
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• pp.123-127
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• 1985

Incidence of the Fusarium wilt caused by F. oxysporum f. sp. vasinfectum of sesame (var. Kwangsan) was remarkably influenced by seeding date and mean air temperature in the field of two or three year's continuous cropping with sesame in 1983 and 1985. Sesame were seeded on six different dates from April 20 to July 5. Air temperature was checked daily at the meteorological station near the experimental field. Low($16{\sim}20^{\circ}C$) and high temperature($20{\sim}25^{\circ}C$) periods were provisionally devided, based on every ten-day mean daily temperature during field experiment for last ten years, which corresponded to before and after June 15 in Jinju, Gyeong-nam. Infection rates were 83.7%, 68.2% and 59.4% in the plants grown for 55 days (seeding date: April 20), 40 days(May 5) and 25 days(May 20) under low temperature. On the other hand, infection rates were below 3% in those plots seeded during high temperature period. The longer the growth period exposed to low temperature, the higher was infection rates. It is interesting to note that 40 days old seedling or older are prone to severe infection compared to the younger ones, in higher temperature of $20{\sim}25^{\circ}C$. Therefore, seedlings in vegetative growth stage are less prone to infection than these in reproductive growth stage. The result showed that air temperature during sesame growth was one of the most important factor affecting the incidence of Fusarium wilt. This suggested that sesame crop, which is of tropical origin, has been predisposed to Fusarium wilt, when the plants were exposed to low temperature of $16{\sim}20^{\circ}C$.

• Reproductive and Developmental Biology
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• v.28 no.3
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• pp.181-185
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• 2004

This study was conducted to examine whether activation treatments, source of oocytes and culture conditions affect in vitro developmental ability of caprine oocytes. Mature Korean native goats were pretreated with intravaginal CIDR for 10 days. The goats were then treated with a single intramuscular injection of 1,000 IU PMSG on Day 8 or twice daily injection of a total of 70 mg FSH for 3 days from Day 8 of CIDR insertion for superovulation. All the goats were injected with 10 mg PGF/sub 2a/ on Day 8 and 400 IU hCG on Day 10 of CIDR. Oocytes were surgically collected by oviduct flushing(in vivo maturation) or direct follicle aspiration(in vitro maturation) through mid-ventral incision at 35 h after hCG injection. Fifteen to twenty oocytes were placed in TCM-199 medium containing 25 mM Hepes and hormones under mineral oil at 39℃ in a humudified atmosphere of 5% CO₂ in air for 22 to 24 h. After maturation, the oocytes were activated by electric stimulation or ionomycin + 6-DMAP. The activated oocytes were then cultured in M16, TCM-199 and mSOF media supplemented with proteins at 39℃ for 6 to 7 days. Activation treatments did not affect cleavage of the oocytes. The cleavage rates were 64.1% (41/64) in oocytes activated by electric stimulation and 76.5% (218/285) in oocytes activated by ionomycin + 6-DMAP. The proportion of development to blastocyst was 15.6% (34/218) in oocytes activated by ionomycin + 6-DMAP, but activation by electric stimulation did not support embryos developed beyond morula stage. There were no differences in the cleavage rates of activated oocytes experiencing in vivo (86.8%, 66/76) and in vitro maturation (69.0%, 127/184). However, the development rate to blastocyst stage was significantly (P<0.05) higher for oocytes matured in vivo (50.0%, 33/66) compared to in vitro (0.8%, 1/127). Culture conditions did not affect the cleavage of -activated oocytes. The cleavage rates were 51.6% (49/95) in M16, 64.3% (18/28) in TCM-199 and 81.0% (145/179) in mSOF, respectively. By contrast, the development rate of activated oocytes to stage was greater (P<0.05) for oocytes cultured in mSOF medium (23.4%, 34/145) than in M16 or TCM-199 (0.0%). Our results suggest that source of oocytes and culture conditions are major factors affecting in vitro development of caprine parthenogenetic oocytes.

• Reproductive and Developmental Biology
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• v.28 no.1
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• pp.21-27
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• 2004

This study was conducted to investigate the developmental ability of caprine embryos after somatic cell interspecies nuclear transfer. Recipient bovine and porcine oocytes were obtained from slaughterhouse and were matured in vitro according to established protocols. Donor cells were obtained from an ear-skin biopsy of a caprine, digested with 0.25% trypsin-EDTA in PBS and primary fibroblast cultures were established in TCM-199 with 10% FBS. The matured oocytes were dipped in D-PBS plus 10% FBS ＋ 7.5 $\mu$ g/ml cytochalasin B and 0.05M sucrose. Enucleation were accomplished by aspirating the first polar body and partial cytoplasm which containing metaphase II chromosomes using a micropipette with an out diameter of 20∼30 $\mu$m. A Single donor cell was individually transferred into the perivitelline space of each enucleated oocyte. The reconstructed oocytes were electric fusion with 0.3M mannitol fusion medium. After the electrofusion, embryos were activated by electric stimulation. Interspecies nuclear transfer embryos with bovine cytoplasts were cultured in TCM-199 medium supplemented with 10% FBS including bovine oviduct epithelial cells for 7∼9 day. And porcine cytoplasts were cultured in NCSU-23 medium supplemented with 10% FBS for 6 ∼8 day at $39^{\circ}C, 5% CO_2 $in air. Interspecies nuclear transfer by recipient bovine oocytes were fused with electric length 1.95 kv/cm and 2.10 kv/cm. There was no significant difference between two electric length in fusion rate(47.7 and 44.6%) and in cleavage rate(41.9 and 54.5%). Using electric length 1.95 kv/cm and 2.10 kv/cm in caprine-porcine NT oocytes, there was also no significant difference between two treatments in fusion rate(51.3 and 46.1%) and in cleavage rate(75.0 and 84.9%). The caprine-bovine NT oocytes fusion rate was lower(P＜0.05) in 1 pulse for 60 $\mu$sec(19.3%), than those from 1 pulse for 30 $\mu$sec(50.8%) and 2 pulse for 30 $\mu$sec(31.0%). The cleavage rate was higher(P＜0.05) in 1 pulse for 30 $\mu$sec(53.3%) and 2 pulse for 30 $\mu$sec(50.0%), than in 1 pulse for 60 $\mu$sec(18.2%). The caprine-porcine NT oocytes fusion rate was 48.1% in 1 pulse for 30 $\mu$sec, 45.2% in 2 pulse for 30 $\mu$sec and 48.6% in 1 pulse for 60 $\mu$sec. The cleavage rate was higher(P＜0.05) in 1 pulse for 30 $\mu$sec(78.4%) and 1 pulse for 60 $\mu$sec(79.4%), than in 2 pulse for 30 $\mu$sec(53.6%). In caprine-bovine NT embryos, the developmental rate of morula and blastocyst stage embryos were 22.6% in interspecies nuclear transfer and 30.6% in parthenotes, which was no significant differed. The developmental rate of morula and blastocyst stage embryos with caprine-porcine NT embryos were lower(P＜0.05) in interspecies nuclear transfer(5.1%) than parthenotes(37.4%).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.460-470
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• 1985

Experiments were carried out to evaluate the standard gravity in determining potential kernel size and to determine the effective sampling way by analyzing intra - and inter - plant variations for some source and sink characters using eleven semi-dwarf indica and three japonica cultivars including four semi-dwarf indica nearisogenic lines. Also, additional experiments were conducted to understand yearly variation and variety x year interaction effects for ten characters related to source and sink and to characterize the varietal difference of pre- and post-heading self-competition employing three parental varieties and their F$\sub$5/ progenies in 1982 and 1983. It is desirable to determine the potential kernel size by average kernel wight of rice grains showing above 1.15 specific gravity. There was significant difference in leaf area per tiller, spikelets and sink capacity per panicle among vigorous, intermediate and inferior tillers classified by differentiated order and vigorousness. Although it was difficult to find out any significant difference in grain-fill ratio, ratio of perfectly ripened grain, potential kernel size and sink/source ratio between vigorous and intermediate tillers, there was big difference between them and inferior one. The coefficients of variation within each tiller-group for some characters related to source and sink were larger with the order of vigorous tillers < intermediate one '||'&'||'lt; inferior one, and the average heritability of all characters, evaluated by the ratio of varietal variance (equation omitted) to total variance (equation omitted), were higher with the order of inferior tillers '||'&'||'lt; intemediate one '||'&'||'lt; superior one. Therefore, it is desirable to sample the vigorous tillers to represent the varietal difference of these traits. '82-'83 year variations of three parental cultivars were significant for all traits except for leaf area/tiller, panicles/hill, leaf area index and rough rice yield. The characters showing highly significant variance of variety x year interaction were growth duration from transplanting to heading, leaf area/tiller, sink/source ratio, sink capacity/panicle and grain yield. Generalized yearly response of three parental varieties (Suweon 264, Raegyeong, IR1317-70-l) and their F$\sub$5/ progenies on the 1st and 2nd principal components extracted from ten source and sink characters generally exhibited reduction in both source and sink. However, there were diverse variety x year interactions such as progenies showing similar reaction with their parents and intermediate or recombinational yearly response with little or considerable yearly movement on the four-dimensional planes of the two upper principal components between 1982 and 1983. Sink characters revealing highly significant border effect were grain-fill ratio, spikelets and sink capacity per panicle. Among them the latter two especially showed significant variety x border effect interaction. Self-competition characterized by relative weakness of inside plant's sink characters compared to the border one was more severe during the reproductive stage before heading than maturing stage. Though the larger sink capacity per panicle generally disclosed the severer self-competition, some lines (like Suweon 264) revealed severe self-competition with small sink capacity while a few others showed tender self-competition in spite of big sink capacity per panicle.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.158-164
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• 1985

The objective of the study was to investigate growth pattern of capsule and grain to improve grain filling during the grain filling period in sesame. Growth patterns of capsule and grain from anthesis to maturity were measured and compared by different plant types. Growth of capsule length started to grow just after anthesis and recorded maximum point at 35 days after flowering. and then decreased gradually. Growth of higher part capsule was worse than lower and middle capsules. Capsule growth of 2 carpels 4 loculi type showed better than 4 carpels 8 loculi type and BTB (branch, 3 capsules, 2 carpels, 4 loculi) type showed good growth due to its small reduction of higher part capsule length compared to those of lower and middle parts. The order of growth of capsule length were considered to be center capsule in main stem> center capsule in branch> side capsule in main stem> side capsule in branch. Growth of capsule width also showed maximum at 35 days after anthesis and then reduced. The order of growth of capsule width were lower part> middle part> higher part. Higher part capsule width of 3 capsules 4 carpels 8 loculi type showed serious decrease at late reproductive growth stage same as those of capsule length. Fresh one thousand grain weight showed peak at 35 days after anthesis and then reduced. The order of grain growth were appeared as lower part> middle part> higher part. Growth of fresh one thousand grain weight of branch and side capsule were lower than those of main stem center capsule, and 4 carpels 8 loculi type was deeply decreased at late flowering time in higher part such as the growth of capsule length and width. BTB (branch, 3,2/4) type didn't show much decrease in higher part fresh grain weight compared to those of other plant types in spite of its profitable character of lots of sink capacity. BTB type appeared to be ideal for improving grain filling and yield productivity in growing sesame in Korea.