• Animal cells and systems
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• 제7권2호
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• pp.119-122
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• 2003

In order to determine whether foals of move dominant mothers were harassed less by mares than those of lower-ranked mothers, harassment of foals was studied in a herd of Jeju ponies (Equus caballus) consisting of 73 mares, their 53 foals, and one stallion. Mares Harassed the foals on 71 occasions between March to September,1998. The frequency of harassment tended to decrease as foals aged, but the relationship was not significant (P = 0.079). Foals were harassed when sleeping (n = 14), grazing (n = 19), moving (n = 8), approaching a mare in the vicinity (n = 13), or play-fighting with the foal of the harassing mare (n = 17). Mares harassed foals of younger, more subordinate mares than those of older, more dominant mares (P < 0.001). We conclude that early social experience of foals is associated with the dominance rank of its mother.

• Asian-Australasian Journal of Animal Sciences
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• 제16권5호
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• pp.685-692
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• 2003

Information on nutrient requirements and forage intake of fallow weaner deer is required for the development of feeding strategies during the year. An experiment was conducted in which 60 fallow weaner deer (grazing on medic and ryegrass based pastures) were supplemented with a concentrated diet at three levels. The diet contained 2% minerals, 30% lupin and 68% barley grain. Twelve deer from each treatment were dosed with commercial alkane capsules in May, June, July, September and October to predict nutrient intake. The relationships between body weight gain and intake of metabolisable energy and crude protein were established using a general linear models analysis. Dry matter intake from pastures ranged from 0.137 kg to 0.304 kg in May and June and increased to 1.2 kg in October. Nutrient intake from pastures was strongly influenced by amount of supplementary feed and gender. Digestible energy intake from pastures was 1.3, 3.8 and 6.1 MJ/day higher for males than females in July, August and October, respectively. The protein and energy intake was strongly correlated with body weight gain. The energy requirement for maintenance were 7.3, 8.2, 10.2, 10.2 and 10.7 MJ DE/day and the DE required for each kg body weight gain were 19, 18, 29, 34 and 49 MJ in May, June, August and October, respectively. The protein requirement for maintenance was 12.2, 12.6, 15.0, 11.4 and $8.5g/W^{0.75}$ in May, June, July, August and October, respectively. The nutrient requirement defined from this study can be used to assist farmers to explore the possible pasture and stock management practices under southern Australian conditions. However, further research is required to develop rapid and cheap methods for estimating dry matter intake, nutritive value of pastures and to quantify the potential growth rate of fallow deer in southern Australia.

• Macromolecular Research
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• 제16권7호
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• pp.575-585
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• 2008

There are two beamlines (BLs), 4C1 and 4C2, at the Pohang Accelerator Laboratory that are dedicated to small angle X-ray scattering (SAXS). The 4C1 BL was constructed in early 2000 and is open to public users, including both domestic and foreign researchers. In 2003, construction of the second SAXS BL, 4C2, was complete and commissioning and user support were started. The 4C2 BL uses the same bending magnet as its light source as the 4C1 BL. The 4C1 BL uses a synthetic double multilayer monochromator, whereas the 4C2 BL uses a Si(111) double crystal monochromator for both small angle and wide angle X-ray scattering. In the 4C2 BL, the collimating mirror is positioned behind the monochromator in order to enhance the beam flux and energy resolution. A toroidal focusing mirror is positioned in front of the monochromator to increase the beam flux and eliminate higher harmonics. The 4C2 BL also contains a digital cooled charge coupled detector, which has a wide dynamic range and good sensitivity to weak scattering, thereby making it suitable for a range of SAXS and wide angle X-ray scattering experiments. The general performance of the 4C2 BL was initially tested using standard samples and further confirmed by the experience of users during three years of operation. In addition, several grazing incidence X-ray scattering measurements were carried out at the 4C2 BL.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.333-333
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• 2006

We synthesized two novel polynorbornene derivatives, chiral poly(norbornene acid methyl ester) (C-PNME) and racemic poly(norbornene acid n-butyl ester) (R-PNME), which are potential low dielectric constant materials for applications in advanced microelectronic and display devices. Thin films of these polymers deposited on substrates were investigated by structural analyses using synchrotron grazing incidence X-ray scattering, specular reflectivity and ellipsometry. These analyses provided important information on the structure, electron density gradient across film thickness, chain orientation, refractive index and thermal expansion of the polymers in substrate-supported thin films. The structural characteristics and properties of the thin films were first dependent on the polymer chain' tacticity and further influenced by film thickness and thermal annealing.

• Asian-Australasian Journal of Animal Sciences
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• 제15권11호
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• pp.1611-1616
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• 2002

The alkanes in plant materials can potentially be used as markers to estimate composition and digestibility of diet of deer for the development of feeding strategies, but the analysis of alkanes in plant materials and deer faeces is time-consuming and expensive. In this study, 242 faecal samples and 119 pasture samples were scanned using near infrared spectroscopy (NIR) and the concentrations of alkanes in these samples were analysed to develop calibrations for predicting alkane concentrations in pastures and deer faeces. The $R^2$ values for NIR calibrations were <0.6 for $C_{24}$, $C_{26}$, $C_{32}$ and $C_{36}$, but were >0.8 for other alkanes for faecal samples. The $R^2$ values were >0.87 for alkanes with chains from $C_{27}$ to C35 for pasture samples. However, NIR was unable to predict concentrations of alkanes with chains of $C_{24}$, $C_{26}$, $C_{32}$ and $C_{36}$ in faecal samples and $C_{24}$, C25, $C_{26}$ and $C_{36}$ in pasture samples. While the use of these NIR calibrations will accelerate the estimation of diet digestibility, dietary components and botanical composition of pastures, the influence of the type of pasture on NIR calibration will require further examination.

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.401-409
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• 1992

Genotype $\times$ environment (G $\times$ E) interactions must be understood if they are to be exploited to improve animal production, particularly in production systems associated with large environmental variations. The measurement and evaluation of G $\times$ E are discussed. Examples are presented that demonstrate G $\times$ E in different breeds of beef cattle for high temperatures, internal and external parasites and changes in quantity and quality of nutrition. It is demonstrated that productivity differences between genotypes or breeds under grazing conditions arise because of differences between genotypes in the combination of production potential and resistance to environmental stresses in relation to the levels of the relevant environmental stresses that are operating at the time. The $F_1$ cross between genotypes with high production potential (e.g. European Bos Taurus breeds) and those with high resistance to environmental stress (e.g. Asian and African Bos indicus and sanga breeds) is an exceptional genotype with a unique combination of these two sets of attributes. The principles for G $\times$ E developed for beef cattle are briefly discussed in relation to dairy cattle, pigs, poultry and buffalo.

• Asian Journal of Atmospheric Environment
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• 제4권1호
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• pp.33-41
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• 2010

Because ammonia from livestock production may substantially contribute to environmental pollution, emissions from all possible sources (housing systems, manure storage, manure application, outside grazing) should be reduced. The purpose of this study was to investigate the effect of different bedding materials on ammonia emissions in a cow house. By applying a combination of four treatment types: treatment $1-T_1$ (sawdust (50%)+sawdust pellets (50%)), treatment $2-T_2$ (sawdust (50%)+corn stalk pellets (50%)), treatment $3-T_3$ (sawdust (100%)), and treatment $4-T_4$ (sawdust (50%)+palm kernel meal pellets(50%)) as bedding materials in a cow house, the effects of such treatments on ammonia flux were assessed in approximately one month. The magnitude of ammonia emissions (mg $m^{-2}\;min^{-1}$) varied in the following order: $T_1$(2.226), $T_4$(2.052), $T_2$(1.845), and $T_3$(1.712). The patterns of pH had a decreasing trend for all bedding treatments during the experiment, and there was no significant relationship with ammonia flux. The results reveal that the most important factor influencing ammonia emissions is the physical structure of the bedding types.

• 한국산림과학회지
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• 제99권2호
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• pp.163-171
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• 2010

Forest fires have potentials to change the structure and function of forest ecosystems and significantly influence on atmosphere and biogeochemical cycles. Forest fire also affects the quality of public benefits such as carbon sequestration, soil fertility, grazing value, biodiversity, or tourism. The prediction of fire occurrence and its spread is critical to the forest managers for allocating resources and developing the forest fire danger rating system. Most of fires were human-caused fires in Korea, but meteorological factors are also big contributors to fire behaviors and its spread. Thus, meteorological factors as well as social factors were considered in the fire danger rating systems. A total of 298 forest fires occurred during the fall season from 2002 to 2006 in South Korea were considered for developing a logistic model of forest fire occurrence. The results of statistical analysis show that only effective humidity and temperature significantly affected the logistic models (p<0.05). The results of ROC curve analysis showed that the probability of randomly selected fires ranges from 0.739 to 0.876, which represent a relatively high accuracy of the developed model. These findings would be necessary for the policy makers in South Korea for the prevention of forest fires.

• ALGAE
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• 제30권1호
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• pp.67-79
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• 2015

Planktivorous fish which limit zooplankton grazing have been predicted to increase algal biodiesel production in wastewater fed open reactors. In addition, tanks with higher algal diversity have been predicted to be more stable, more productive, and to more fully remove nutrients from wastewater. To test these predictions, we conducted a 14-week experiment in Houston, TX using twelve 2,270-L open tanks continuously supplied with wastewater. Tanks received algal composition (monocultures or diverse assemblage) and trophic (fish or no fish) treatments in a full-factorial design. Monocultures produced more algal and fatty acid methyl ester (FAME) mass than diverse tanks. More than 80% of lipids were converted to FAME indicating potentially high production for conversion to biodiesel (up to $0.9T\;ha^{-1}y^{-1}$). Prolific algal growth lowered temperature and levels of total dissolved solids in the tanks and increased pH and dissolved oxygen compared to supply water. Algae in the tanks removed 91% of nitrate-N and 53% of phosphorus from wastewater. Monocultures were not invaded by other algal species. Fish did not affect any variables. Our results indicated that algae can be grown in open tank bioreactors using wastewater as a nutrient source. The stable productivity of monocultures suggests that this may be a viable production method to procure algal biomass for biodiesel production.

• 생태와환경
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• 제41권1호
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• pp.26-33
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• 2008

To understand the effect of water temperature on growth pattern of Stephanodiscus sp., we weekly or biweekly investigated in the lower part of the Nakdong River from 1994 to 2006 and performed a laboratory experiment. Stephanodiscus was the most dominant species among phytoplankton in winter when low flow persisted and the high abundances of the species were maintained from December to February. Three strains of Stephanodiscus sp. were isolated for the in vitro experiment from the Nakdong River in January 2005. Over the water temperature range of $4^{\circ}C$ to $20^{\circ}C$, the growth patterns of Stephanodiscus sp. were different in the short-term batch culture. The maximum cell density of Stephanodiscus sp. was observed at approximately $5^{\circ}C$ in the river systems, but the optimum water temperature of Stephanodiscus sp. was $10^{\circ}C$ for the growth in the laboratory experiment. However, the proliferation of Stephanodiscus sp. was related to low water temperature in the Nakdong River.