• Clinical and Experimental Reproductive Medicine
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• 제26권3호
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• pp.399-405
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• 1999

Objective: In the preparation of ICSI, cumulus and corona cells should be removed from the oocytes by using a combination of enzymatic (hyaluronidase) and mechanical (pipetting) methods. But little is known about the effects of different degrees of oocyte denudation and incubation time between denudation and sperm injection on the outcomes of ICSI. The aim of this study was to evaluate the effects of varying the degrees of oocyte denudation and the lengths of incubation time from denudation to sperm injection on the outcomes of ICSI. Methods: In experiment 1, patients (oocytes) were grouped into group A and B according to the degree of denudation, complete and partial, respectively. In experiment 2, patients (oocytes) were grouped into group I, II and III according to the length of incubation time of denuded oocytes until sperm injection as < 1, $1{\sim}2$ and >2 hours, respectively. Results: There was no significant difference between the degree of oocyte denudation on the survival, fertilization and development rates after ICSI procedure. In case of the incubation time of denuded oocytes until ICSI, survival rates was higher in group III (83.1 %) than in group I (61.5%, p<0.05) or group II (64.3%). However no statistically significant differences were found between incubation time and fertilization or development rates. Conclusions: This study reveals that the outcomes of ICSI are not affected by the degree (complete or partial) of oocyte denudation. However, the denuded oocytes with incubation period of more than 2 hours show better outcomes of ICSI than those with the incubation period of less than 2 hours.

• Mycobiology
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• 제34권2호
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• pp.83-91
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• 2006

Characteristic growth patterns of Cordyceps militaris isolates on various media, under varying light conditions and at varying incubation periods were examined. Light was found to be the most critical single factor in determining the density, texture, and pigmentation of the mycelial culture of the fungus. However, under the light condition, the degree of pigmentation and mycelial density were found to be affected by the incubation period and type of medium. Irrespective of the variations in medium type or incubation period, there was no pigmentation of the mycelium under dark condition. Radial growth of the mycelium was faster under dark incubation rather than under light incubation. Abundant mycelial density and darkest pigmentation of C. militaris isolates were produced in nutritionally rich media like SDAY, SMAY and CZYA, suggesting that these media may fulfill all the requirements for vegetative growth of the fungus. Growth characteristics of C. militaris isolates could be easily observed by the simple agar culture method, which would be useful to characterize the phenotypic characteristics of large number of pure cultures of the fungus under given conditions of growth factors such as medium, light and temperature.

• Asian Journal of Innovation and Policy
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• 제7권3호
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• pp.489-510
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• 2018

Institution-based Technology Business Incubators are on the rise in India, as a means of promoting innovation-based tech start-up ecosystems, due to increased policy initiatives. Against this background, we have traced the origin and process of building a start-up ecosystem in IIT Madras, Chennai of India, based on semistructured interviews held with the stakeholders of the ecosystem. Subsequently, we have ascertained the key components of IIT Madras start-up ecosystem, and the process of incubation comprising pre-incubation, incubation and post-incubation phases. Finally, we have derived the key lessons from the ecosystem development experience and incubation process which enable generation of start-ups from both students and faculty, apart from alumni and ex-industry executives. Though this ecosystem model has emerged over a period of time through learning and experience, the ecosystem is able to generate more than 100 start-ups, majority of them being from students and faculty. Thus, the evolved start-up ecosystem of IIT Madras is able to generate faculty-supported and student-led entrepreneurship successfully.

• Asian-Australasian Journal of Animal Sciences
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• 제7권1호
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• pp.75-81
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• 1994

To elucidate the relationship between steroidogenesis and sex differentiation in the duck, plasma, testicular and ovarian testosterone, estradiol-$17{\beta}$ and progesterone concentration in male and female embryo of day 11 to 27 (just before hatching) of incubation and in 1- to 7-day-old male and female duckling were investigated by radioimmunoassays. Plasma estradiol-$17{\beta}$ concentration in female embryos declined from very high at days 11 and 15 of incubation and remained at low levels after hatching. Male plasma estradiol-$17{\beta}$ concentration were always lower than those of the female throughout this period. Plasma testosterone and progesterone concentrations in both sexes were low during the embryonic stage, but then increased to peaks 3 days and 1 day after hatching, respectively. Estradiol-$17{\beta}$ contents were much higher in the left ovary than the right ovary or testes throughout the experimental period. The estradiol-$17{\beta}$ content of the left ovary was very high at day 15 of incubation, and decreased gradually thereafter. Both in right ovary and testes, estradiol-$17{\beta}$ contents were always low. Testosterone and progesterone contents in the left ovary were low from day 11 to 23 of incubation, and reached a peak 1 day after hatching. Progesterone content in the right ovary and testes were low levels over time period examined. Testosterone and progesterone contents were much higher in the left ovary than the right ovary and testes. The present results clearly demonstrate that the capacity of the embryonic left ovary of duck to synthesize estradiol-$17{\beta}$ and testosterone is much higher than that of the embryonic testis. It is suggested that estrogen secreted from the embryonic ovary earlier than day 15 of incubation has an important role in female sexual differentiation in the duck, and the sex of the avian species is basically male with homozygous sex chromosome (ZZ).

• Asian-Australasian Journal of Animal Sciences
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• 제9권3호
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• pp.303-307
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• 1996

The degree of autolysis and presence of cell-wall degrading enzymes in an anaerobic ruminal fungus, Piromyces communis OTSI, grown in liquid medium, was monitored to evaluate the effect of self-digestion on fungal biomass. After a 30 days incubation period fungal dry weight decreased by 45% and the cell wall component chitin decreased by 22%. Chitinase activity detected in the supernatant was mainly of the endotype and peaked at day 6 of the incubation. ${\beta}-1$, 3-glucanase was detected from day 4 and increased throughout the incubation period. Autolysis was a slow process, and under natural conditions it is unlikely that it plays a significant role in the degradation of the spent fungal vegetative stage in the rumen.

• 한국버섯학회지
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• 제16권2호
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• pp.96-102
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• 2018

꽃송이버섯 안정생산을 위해 액체종균배지조성 및 배양조건에 관한 연구결과, 물엿을 8Brix%로 조절하고 질소원으로 Yeast extract를 0.2%첨가한 배지에서 균사생장량이 우수하여 적합 배지로 선발하였다. 통기량에 따른 $CO_2$ 발생량은 배양 9일까지 증가하다 감소하였고, 통기량이 높을수록 균체직경은 작아지고 배지감소율은 증가하여 통기량 0.9vvm이상에서 배지감소율이 급증하여 꽃송이버섯 액체종균에 적합한 통기량은 0.3~0.6 vvm 이 적합하였다. 또한, 배양기간일 길수록 균체량이 많았으나, $CO_2$ 발생량이 높고 배지감소율이 낮은 9~11일을 적합 배양기간으로 설정하였다.

• Journal of the Korean Data and Information Science Society
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• 제20권1호
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• pp.149-158
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• 2009

쯔쯔가무시증은 가을철 유행성 출혈열 중 80%이상을 차지하는 질병으로 1주에서 2주의 잠복기를 가지는 것으로 알려져 있다. 우리는 그 잠복기간의 확률분포가 감마분포라 가정하고 후향연산식을 이용하여, ${\hat{\mu}}=309.92$$, ${\hat{\sigma}}=14.154$인 정규분포를 따르는 감염자 분포를 추정하였다. 감염자는 10월에 집중적으로 분포하는 것으로 나타났다. 이러한 감염자 분포형태는 발병자 수가 11월동안 급격하게 증가하는 것에 기인한다. 본 연구에서 추정한 감염확률에 의해 미래의 유병자수를 계산한 결과 최대 1200명이었고 이는 매년 증가하는 발병자 수의 경향을 반영하지 못한 한계가 있다. 또한 우리는 전염병 모형으로 잘 알려져 있고 전염발전 단계간의 상호작용을 고려하는 SIRS 모형을 적용해 보았다. 모수는 초기값으로부터 잘 근사되어 수렴하는 값으로 추정하였다.

• 한국가금학회지
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• 제27권3호
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• pp.259-266
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• 2000

This study was carried out to investigate the embryonic developmental changes of the pineal gland during incubating period in the Korean pheasant. The pheasant embryos and fetuses were killed after 3, 4, 6, 9, 12, 15, 19 and 23 (hatching) days of incubation. The morphological characteristics of a pineal gland were determined in all embryos and fetuses using the whole - mount technique, light microscopy and morphometry. The time of the first apparition of the pineal anlage, as a derivative of the roof of the third ventricle, was fixed at 3 days of incubation. The pineal vesicles appeared as solid mammilliform projections, which subsequently presented a central lumen, at 4 days of incubation. The pineal parenchyma was composed of the tubular pineal recess, the lobules surrounded with septum originating from the capsule and the follicles possessed central lumen at 23 days of incubation. The length, width and area of the pineal gland were increased markedly at 9 and 15 days of incubation. These results suggest that the pineal recess has an important role in the pineal development after hatching.

• 한국생태학회:학술대회논문집
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• 한국생태학회 2002년도 VIII 세계생태학대회
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• pp.107-111
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• 2002

During the breeding season of 1998, breeding ecology of the Great Reed-Warbler (Acrocephalus arundinaceus orientalis) was studied at Yangsoo-ri and Yongdam-ri of the Yangpyung-gun, Kyunggi province, Korea. Egg-weight (CV: 6.25) was more variable than either length or breadth, and breadth was the least variable of the measures. Significant variations In overall egg-weight occurred between clutches, and that more of the total variation in egg-weight and shape are due to inter-clutch variation as to intra-clutch variation when the data were pooled. The last egg tends to be larger than the remaining eggs in the clutch of the Great Reed-Warbler, suggest- ing the Great Reed-Warbler may adopt the brood-survival strategy. When method 3 was used, the most common incubation period is 12 days. In the Great Reed-Warbler, the length of the incubation period was related to clutch-size when method 1 (r=0.485, p<0.05) and method 2 (r=0.621, p<0.01) were employed, but not related to egg weight. The average number of days of hatching asynchrony was 2.5, raging 0.5∼2.5. Asynchronous hatching was related to the clutch size (r=0.66, p<0.01). Hatching sequence was closely related to the laying sequence (r=0.93, p<0.001), suggesting Great Reed-Warblers incubate their eggs before clutch completion. The effect of egg weight on hatching asynchrony was found in Great Reed-Warblers (t-test, p<0.01).

• 대한수의학회지
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• 제15권2호
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• pp.177-180
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• 1975

This study was undertaken to obtain more detailed knowledge of the oxygen consumption rate of chick embryos, of the relationship between the increasing rate of embryo weight and that of oxygen consumption, of the daily increase of oxygen consumption by that of embryo weight, and of the metabolic rate of the White Leghorn eggs. The results obtained are summarized as follows. 1. The average oxygen consumption rate of the chicken embryo at the 3rd day of incubation is 0.8ml/h, STPD. It is strongly suggested that this value can used as a physiological criterion to classify the fertilized and unfertilized eggs, on the other hand oxygen consumption rate of the fertilized eggs reaches a plateau between the 18th and 20th days. 2. There exists a parallel relationship between the increasing rate of embryo weight and that of oxygen consumption rate during the incubation period. 3. There are not exist a parallel relationship between the daily increase of embryo weight and that of oxygen consumption during the whole incubation period. 4. The metabolic rate of chicken embryo(ml/h/g) is highest in the early stage of incubation and it started to decrease sharply until the 8th day follow by slow decrease thereafter.