• Ocean and Polar Research
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• v.30 no.1
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• pp.11-19
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• 2008

Incubation routine and sex role of Streaked Shearwaters Calonectris leucomelas at Sasudo Island, in Jeju, South Korea, were studied during the incubation period, June to August in 2002. Incubation routine in Procellariiformes represents a sequence of alternating shifts taken in turn by female and male in a species-specific pattern. Hence, coordination of individual incubation rhythms between partners is crucial for successful breeding attempt. In Streaked Shearwaters, incubation routine represents a sequence of alternating shifts taken in turn by male and female. The first incubation shift was made by male after female had laid the egg. The mean incubation period was 50.8 days until hatching. Males had spent on average 26.5 days incubating and females 24.3 days accordingly. The mean duration of incubation shifts decreased progressively from 6th and 7th shift to hatching. Overall, males had spent more time incubating than females during the incubation period, but the mean duration of the incubation shift 5.6 days for males and 5.7 days for females did not differ between males and females. There were no effect of the body size of the breeding pair on incubation performance. For males the mean of body weight decreased during the incubation, whereas for females it remained approximately stable. In Streaked Shearwaters, the duration of incubation shift and subsequent foraging trip are related to loss of body weight during the period of fasting. In addition, coordination of individual incubation rhythms affects their incubation behaviour.

• Journal of Plant Biotechnology
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• v.50
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• pp.267-274
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• 2023

All studies on date palm somatic embryogenesis have focused on germination in the presence of light while neglecting germination in darkness, which mimics the germination process of zygotic embryos within seeds. To improve the date palm micropropagation protocol, we investigated the effects of light and darkness incubation on the germination of indirect date palm somatic embryos and their subsequent conversion into plantlets. Darkness incubation emerged as a pivotal factor in the germination of indirect date palm somatic embryos and their successful conversion into plantlets. Darkness incubation significantly decreased the time required for the conversion of indirect somatic embryos into plantlets, halving the duration from 24 weeks to only 12 weeks. The micropropagation protocol was modified, consolidating the previous two distinct stages of germination and elongation under light incubation into a single stage under darkness incubation. These findings modified the protocol and significantly reduced the overall duration of the date palm micropropagation protocol.

• Journal of Forest and Environmental Science
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• v.28 no.4
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• pp.289-294
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• 2012

This study was conducted from April 2012 to June 2012 to analyze breeding status of Black woodpeckers (Dryocopus martius) in the Gayasan National Park. Nest height, tree diameter which a nest built and altitude at the nest site of Black woodpeckers were 17.4 m, 63.8 cm and 587 m, respectively. A pair of Black woodpeckers completed a clutch in 4 eggs on 7 May and 3 of eggs hatched on 24 May 2012. Both female and male incubated eggs and never left eggs without one of parents. A male more contributed to build a nest than a female. Incubation duration was higher in a male than in a female. Nestlings made a begging call in a nest during the growing period. Begging frequency of nestlings increased from 11 days up to 20 days after hatching. After then, nestlings reduced begging and fledged a nest 24 days after hatching. This study provided information of breeding ecology to protect and manage population of Black woodpeckers which are endangered species in South Korea.

• Journal of Radiation Industry
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• v.5 no.3
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• pp.197-202
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• 2011

In this study, an Ag-polyaniline-silica (Ag-PANI-silica) nanoparticle was evaluated as a radioisotope carrier. An Ag-PANI-silica nanoparticle was incubated in the $^{125}I$ solution for a duration of 24 hr to test its radioisotope absorptivity. During the incubation, radioactivity of the nanoparticle was measured at 3, 6, 12, and 24 hr. After a 24 hr incubation, $^{125}I$-Ag-PANI-silica nanoparticle was incubated in a fresh saline for a duration of 48 hr to check its stability. Additionally, the $^{125}I$-Ag-PANI-silica nanoparticle was injected to the ICR mouse to investigate its in-vivo distribution characteristics. The $^{125}I$ absorption yield of the Ag-PANI-silica nanoparticle was higher than 95% after a 6 hr incubation period in the $^{125}I$ solution. And $^{125}I$-Ag-PANI-silica was stable for 48 hr at 80% yield at room temperature. The SPECT/CT image of a mouse that received $^{125}I$-Ag-PANI-silica complex showed that the $^{125}I$-Ag-PANI-silica complex was distributed in the lung, stomach and thyroid at 30 min post injection. From these results, the Ag-PANI-silica nanoparticle has good radio-iodine carrying property and can be applicable for the purpose of diagnosis and therapy.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.4
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• pp.51-60
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• 2002

This study was carried out to develop the biochemical pulping method to enhance energy saving and decrease the capital cost through the soda pulping under atmospheric pressure (100%). Nonwood substrates, rice straw, were pretreated by white-rot fungi, Ganoderma Iucidum. It has acquired several basic data that can be applied in bio-soda pulping. The results of this study were as follow. Without any nutrients or with glucose, N and glucose+N the weight losses of rice straws inoculated by Canoderma Iucidum were 8.5~29.8%, 9.3~32% 11.8~30.1% and 11.8~24.4% respectively for 5, 10, 15, 20, 25 and 30 days incubation. The more extending incubation periods, the more increasing weight losses. The yield of untreated rice saw was 54.8% after pulping. When any nutrients was not added or glucose, N and glucose+N were added for the pretreatment, the total yields were ranged 50.6~38.5%, 48.6~34.4%, 47.2~38.4% and 49.5~42.6% respectively for 5, 10, 15, 20, 25 and 30 days incubation. The yields were gradually decreased based on extending of incubation. The physical properties of rice straw soda pulps without fungal treatment, the density, breaking length, burst index, tear index and folding endurance were 0.24 g/$\textrm{cm}^3$, 2.32 km, 0.91 kPa $m^2$/g, 56.7 mN.$m^2$/g and 35 times, respectively. After pretreatment without any nutrients or with glucose, N and glucose+N as nutrients the density was 0.27~0.30 g/$\textrm{cm}^3$, the breaking length 3.14~5.25 km, burst index 1.42~2.78 kPa.$\textrm{m}^2$/g, tear index45.8~64.5 mN.$\textrm{m}^2$/g and folding endurance 47~288 times at all incubating periods when pulping was done. The physical properties were increased with the increasing incubation periods. However, when glucose+N was added, the physical properties were shown superior results each incubating duration.

• Environmental Engineering Research
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• v.22 no.4
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• pp.347-355
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• 2017

This study investigated how the combined changes in environmental conditions and nitrogen (N) deposition influence the mineralization processes and carbon (C) dynamics of wetland soil. For this objective, we conducted a growth chamber experiment to examine the effects of combined changes in environmental conditions and N deposition on the anaerobic decomposition of organic carbon and the emission of greenhouse gases from wetland soil. A chamber with elevated $CO_2$ and temperature showed almost twice the reduction of total decomposition rate compared to the chamber with ambient atmospheric conditions. In addition, $CO_2$ fluxes decreased during the incubation under the conditions of ambient $CO_2$ and temperature. The decrease in anaerobic microbial metabolism resulted from the presence of vegetation, which influences the litter quality of soils. This can be supported by the increase in C/N ratio over the experimental duration. Principle component analysis results demonstrated the opposite locations of loadings for the cases at the initial time and after three months of incubation, which indicates a reduction in the decomposition rate and an increasing C/N ratio during the incubation. From the distribution between the decomposition rate and gas fluxes, we concluded that anaerobic decomposition rates do not have a significantly positive relationship with the fluxes of greenhouse gas emissions from the soil.

• Fisheries and Aquatic Sciences
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• v.16 no.1
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• pp.25-34
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• 2013

Early ontogenic development in Siberian sturgeon Acipenser baerii was documented and the effects of different temperatures on embryonic and prelarval development were examined. Photograph-assisted data on morphogenesis in Siberian sturgeon prolarvae agreed well with published descriptions of their ontogeny and ecological behaviors, although certain aspects of differentiation, such as gill covering and scute development, could be rearing condition-sensitive. The present study provides the first characterization of the transient development of teeth during early larval stages; the pattern was congruent with the transition of prolarvae to exogenous feeding. From examinations of embryonic and prelarval development under different temperature conditions ($12-24^{\circ}C$), developmental speed was inversely related with temperature. Overall, hatchability was higher and hatching events were more synchronized at $20^{\circ}C$ than at lower temperatures. After hatching, similar patterns of temperature-dependency were observed in yolk sac absorption and the evacuation of the pigment plug. Our results suggest that the incubation of Siberian sturgeon embryos and prolarvae at temperatures close to $20^{\circ}C$ would be advantageous in hatcheries, based on reductions in the duration and uniformity of egg and prolarval developmental stages.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.102-105
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• 1999

Mineralization of organic N is an important factor in determining the appropriate rate of organic matter application to paddy fields. A kinetic analysis was conducted for nitrogen mineralization of rice, barley, Chinese milk Ovetch (Astragalus sinicus L.; MV) and narrow leaf vetch straw in paddy soil. Nitrogen immobilization occurred rapidly and its rate increased in straw with high C/N ratio. The amount of nitrogen mineralization was rapid in the first year of rice-vetch cropping system. The rate constant (K) depended on the C/N ratio of organic matter. Mineralization of straw increased at high temperature. The amount of available N increment resulted in fast mineralization of straw, especially in rice and barley straw. Chinese milk vetch had the greatest mineralization rate at all temperatures and fertilization levels followed by narrow-leaf vetch. However, rice and barley straws with high C/N ratio immobilized the soil N at the initial incubation duration. Chinese milk vetch or narrow leaf vetch was not effectively mineralized in mixed treatments with rice or barley straw. The mineralization rate of organic matter was mostly affected by the C/N ratio of straw and temperature of incubation. Organic matter with low C/N ratio should be recommended to avoid the immobilization of soil N and the increasing mineralization rate of straw.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.272-274
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• 2003

A few studies have examined the hatching response of copepod diapause eggs to various factors (Ban and Minoda, 1991; Chen and Marcus, 1997). Marcus (1979) monitored the hatching of diapause eggs of Labidocera aestiva and suggested that diapause eggs of marine copepods undergo a refractory phase similar to other diapausing organisms. (omitted)

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.2
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• pp.187-192
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• 1994

This study was conducted to investigate varietal difference in viviparous germinability at different days after heading and temperature conditions. Three Japonica rice varieties, Sobaekbyeo, Odaebyeo and Hwaseongbyeo, and Sare type rice variety, Jakwangdo, showed higher viviparous germination rate from 20 days after heading, while a Tongil type rice, ]ungwonbyeo, and a Indica varieyt, IR-20, showed still low viviparous germination at 40 days after heading. Viviparous germination rate of rice varieties observed at 4 and 10 days after incubation was greately increased with increasing temperature from 15$^{\circ}C$ to 3$0^{\circ}C$ , and germination rate less than 5% was observed at 4 days after incubating at 15$^{\circ}C$ in all rice varieties teased. Viviparous germination pattern of rice varieties was divided into two types. Three Japonica and Sare type rice varieties showed higher and faster in viviparous germination than a Tongil type and Indica rice verieties. Viviparous germination was delayed under day /night fluctuation of incubation temperature compared with day /night fluctuation of incubation temperature compared with day /night constant condition at the same average temperature. The optimum incubation temperature and duration to evaluate viviparous germinability of rice varieties were 25/15$^{\circ}C$ and 6 days, respectively.