• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1727-1734
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• 2005

The fermentation characteristics and mono- and di-saccharides compositions during the early stage of ensiling were studied with a temperate grass, Italian ryegrass (Lolium multiflorum Lam.) and a tropical grass, guineagrass (Panicum maximum Jacq.). The laboratory silos were kept in the room set at 25$^{\circ}C$, and then were opened on 0.5, 1, 2, 3, 5 and 7 days (14 days in Italian ryegrass) after ensiling, respectively. The Italian ryegrass silage showed a fast and large pH decrease caused by a fast and large production of lactic acid during the first 5 days of ensiling and succeeded to achieve lactic acid type fermentation; high lactic acid/acetic acid and lactic acid content at the end of ensiling (14 days), low values of pH (3.74), acetic acid, ethanol and ammonia-N/total nitrogen, none or only small amounts of Butyric acid, valeric acid and propionic acid. The guineagrass silage showed a slow decrease in pH and a slow increase in lactic acid content during the full ensiling period, causing a high final pH value, low contents of lactic acid, acetic acid, total volatile fatty acids and total organic acids. In Italian ryegrass silage, mono- and di-saccharides compositions decreased largely within the initial 0.5 day (12 h) of ensiling. Sucrose disappeared rapidly within the initial 0.5 day of ensiling, but fructose and glucose contents showed an initial rise by the activity of enzymes in plant tissues, and then decreased gradually. On the other hand, the contents of monoand di-saccharides in guineagrass showed the largest decreases due mainly to plant respiration within the initial 0.5 day of ensiling, and no initial rises in fructose and glucose contents during the early stage of ensiling because of the absence of fructans which are hydrolyzed into fructose and glucose in temperate grasses. In both silages, the rate of reduction in mono- and di-saccharides compositions within the initial 5 days of ensiling was ranked in the order of glucose>fructose>sucrose, suggesting that glucose and fructose might be more favorably utilized than sucrose by microorganisms and glucose is the first fermentation substrate. It was concluded that the silage made from Italian ryegrass with high moisture content had a good fermentation quality owing to the dominance of lactic acid bacteria and active lactic acid fermentation during the initial stage of ensiling. These results can be explained by rapid plant sap liberation and the high activity of plant enzyme hydrolyzed fructans into fructose and glucose within the initial 2 days of ensiling, which stimulate the homofermentative lactic acid bacteria growth. In ensiling a temperate grass, the physical characteristics may ensure the rapid onset of fermentation phase, which results from the smaller losses of water-soluble carbohydrates during the initial stage of ensiling and providing sufficient water-soluble carbohydrates for lactic acid bacteria. The silage made from guineagrass with intermediate dry matter and high initial mono- and di-saccharides content was stable silage. This could be explained by the higher incorporation of air during the very early stage of ensiling and the restriction of cell breakdown and juice release due to the properties of a tropical grass with coarse porosity and stemmy structures. These physical characteristics delayed the onset of lactic acid bacteria fermentation phase by extending the phases of respiration and aerobic microorganisms activity, causing the higher loss of water-soluble carbohydrates and the shortage of lactic acid bacteria fermentation substrates.

• The Journal of Fisheries Business Administration
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• v.22 no.2
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• pp.75-99
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• 1991

A quantitative analysis was carried out to monitor the commercial yield level of walleye pollock Theragra chalcogramma in the east coast of Korea, based on available data on catch and fishing effort, catch per unit of effort including fish prices from 1911 to 1988, using a traditional yield model. The results from the quantitative assessment were based to estimate maximum economic yield (MEY) and optimal fishing effort (E-opt) at MEY. On the other hand, interaction aspects between danish seine fishery and trawl fishery mainly targeting walleye pollock in the east coast of Korea were studied to predict optimal situation in fishing effort level from economic point of view which gives the most benefits to the two fisheries. Total production of walleye pollock in 1911 when its catch record was begun for the first time was about 12, 000 metric tons(M/T), and then the catch trend maintained nearly at the level of 50, 000 M/T per annum, showing a decreasing trend until 1930. The highest production from historical data base on walleye pollock fishery statistics was from the years in 1939 and 1940, about 270, 000 M/T and 26, 000 M/T, respectively. No production of the fish species was recorded during the years from 1943 to 1947, and from 1949 to 1951. From 1952 onwards annual production was only available from the southern part of 38$^{\circ}$N in the east coast. During two decades from 1952 to 1970, the production had sustained about less than 30, 000 M/T every year. Annual production showed an increasing trend from 1971, reaching a maximum level of approximately 162, 000 M/T in 1981. Afterwards, it has deceased sharply year after year and amounted to 180, 000 M/T in 1988. The catch composition of walleye pollock for different fishery segments during 1970~1988 showed that more than 70% of the total catch was from danish seine fishery until 1977 but from 1978 onwards, the catch proportion did not differ from one another, accounting for the nearly same proportion. Catch per unit of effort (CPUE) for both danish seine fishery and trawl fishery maintained a decline tendency after 1977 when the values of CPUE were at level of 800 kg/haul for the former fishery and 1, 300 kg/haul for the latter fishery, respectively. CPUEs of gillnet fishery during 1980~1983 increased to about 3.5 times as high value as in the years, 1970~1979 and during 1987~1988 it decreased again to the level of the years, 1970~1978. The bottom longline fishery's CPUE wa at a very low level (20 kg/basket) through the whole study years, with exception of the value (60 kg/basket) in 1980. Fishing grounds of walleye pollock in the east coast of Korea showed a very limited distribution range. Danish seine fishery concentrated fishing around the coastal areas of Sokcho and Jumunjin during January~February and October~December. Distributions of fishing grounds of trawl fishery were the areas along the coastal regions in the central part of the east coast. Gillnet and bottom longline fisheries fished walleye pollock mainly in the areas of around Sokcho and Jumunjin during January~February and December. Relationship between CPUEs' values from danish seine fishery and trawl fishery was used to standardize fishing effort to apply to surplus production model for estimating maximum sustainable yield (MSY) and optimum fish effort (F-opt) at MSY. The results suggested a MSY of 114, 000 M/T with an estimated F-opt of 173, 000 hauls per year. Based on the estimates of MSY and F-opt, MEY was estimated to be about 94, 000 M/T with a range of 81, 000 to 103, 000 M/T and E-opt 100, 000 hauls per year with a range of 80, 000 to 120, 000 hauls. The estimated values of MEY and E-opt corresponded to 82% of MSY and 58% of F-opt, respectively. An optimal situation in the fishing effort level, which can envisage either simultaneously maximum yield or maximum benefit for both danish seine fishery and trawl fishery, was determined from relationship between revenue and cost of running the fleet : the optimal fishing effort of danish seine fishery was about 52, 000 hauls per year, corresponding to 50 danish seiners and 27, 000 hauls per year which is equal nearly to 36 trawlers, respectively. It was anticipated that the net income from sustainable yield estimated from the respective optimal fishing effort of the two fisheries will be about 3, 800 million won for danish seine fishery and 1, 000 million won for trawl fishery.

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.95-108
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• 1984

In order to see the effect of various factors on the success of grafting of walnut, a modified cleft grafting experiment has been conducted with Juglans sinensis Dode, J. regia (persian walnut), J. regiu (carpathian walnut), J. mandshurica, J. nigra and five cultivars of Carpathian walnut as "HANSEN", "METCALFE" "SCHOOL", "ILL CRATH", "LAKE" in a large green house equipped with automatic environmental control system in which temperature of the grafting bed at $28^{\circ}C$ and 85-100% for humidity during the period of January 1981-June 1983. As results of the experiments, the following facts were observed. 1) Hteroplastic grafting was proved to be more successful than homoplastic grafting with all five species tested among the J. regia (carpathian walnut), J. regia (persian walnut), J. sinensis, J. mondshurica, J. nigra. 2) It was interesting to notice that results hight survival of graft high as 99.33-100% with heteroplastic grafting when "Persian Walnut" and "Carpathian Walnut" was grafted on the stock of J. mandshurica and J. nigra. 3) A statistical significance of 5% Level was recognized in the above stocks among five species of homoplastic grafting with heteroplastic grafting and no significance among the scions. 4) The heteroplastic grafting when five cultivars of Carpathian Walnut as above as was grafted on the stock of Juglans nigra and J. mandshurica resulting high survival of graft as high as 85.33-100%. 5) As conclusion, the heteroplastic grafts of Carpathian Walnut and Persian Walnut was grafted on the stock of Juglans nigra and Jugdans mandshurica, the graft union, between stock and scion completed, in short period and was followed by a vigorous growth as well as "Cross Breeding", or hybrization, became apparent, with different desirable traits which could he used to cultivate a Later generation that combined these characteristics.

• Investigative Magnetic Resonance Imaging
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• v.5 no.1
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• pp.43-48
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• 2001

Purpose : To evaluate changes in rabbit liver parenchyma on MR images following percutaneous Holmium-166 injection, and to correlate those changes with histologic findings. Materials and methods. Holmium-166 (10-25 mCi) was percutaneously injected into the liver of rabbit (n=12) under sonographic guidance. MR images were obtained between one to two weeks (acute phasea) after the injection in four rabbits, and between two to four weeks (subacute phase) after the injection in four rabbits. Tissue specimens of these eight rabbits were obtained immediately after MR imaging. Tissue specimens were obtained without MR imaging in four rabbits (between one to two weeks in one rabbit and between three to four weeks in three rabbits). Results : Tissue specimens showed central liquefactive necrosis and peripheral coagulative necrosis containing deposition of small particles and hemorrhage. The peripheral margin of the lesions showed formation of the granulation tissue with fibrosis, which tended to be more prominent in subacute phase. The area of the necrosis tended to correlate with the dose of the radioactive Holmium-166. On MR images, the central portion of the necrosis showed hyperintensity on 72-weighted image, hypointensity on the precontrast T1-weighted images, and no enhancement on the dynamic MR images. The peripheral portion of the necrosis showed hypointensity on T2-weighted images, iso or mild hypointensity on the T1-weighted images, and mild peripheral enhancement on the delayed dynamic MR images. The peripheral margin of the lesion showed hypointensity on both T1- and T1-weighted images with increased enhancement on the delayed phase images of the dynamic MR images. Conclusion : After percutaneous Holmium-166 injection into rabbit liver parenchyma, the central portion showed liquefactive necrosis, the peripheral portion showed coagulative necrosis with granulation, fibrosis, hemorrhage and depostition of small granules. MR imaging may be helpful in evaluation of the histological change of the liver after percutaneous Holmium-166 treatment.

• Neonatal Medicine
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• v.18 no.2
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• pp.320-327
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• 2011

Purpose: To determine the effect of changing practice guidelines designed to avoid hyperoxia or hypoxia in very low birth weight or very preterm infants. Methods: We analyzed a database of <1,500 g birth weight or <32 weeks of gestation infants who were born and admitted to the neonatal intensive care unit of Chungnam National University Hospital from January 2007 to July 2010. First, we defined the relationship between arterial partial pressure of oxygen ($PaO_2$) and pulse oxygen saturation ($SpO_2$). When we evaluated 96 pairs of $PaO_2$ and $SpO_2$ measurements, oxygen saturation was 90-94% at a $PaO_2$ of 43-79 mmHg on the oxyhemoglobin dissociation curve, according to pulse oximetry. Based on this observation, a change in practice was instituted in August 2008 with the objective of avoiding hypoxia and hyperoxia in preterm infants with targeting a $SpO_2$ 90-94% (period II). Before the change in practice, high alarms for $SpO_2$ were set at 100% and low alarms at 95% (period I). Results: Sixty-eight infants the met enrollment criteria and 38 (56%) were born during period II, after the change in $SpO_2$ targets. Demographic characteristics, except gender, were similar between the infants born in both periods. After correcting for the effect of confounding factors, the rates for mortality, severe retinopathy of prematurity, and IVH attended to be lower than those for infants in period II. No difference in the rate of patent ductus arteriosus needed to treat was observed. Conclusion: A change in the practice guidelines aimed at avoiding low oxygen saturation and hyperoxia did not increase neonatal complication rates and showed promising results, suggesting decreased mortality and improvements in short term morbidity. It is still unclear what range of oxygen saturation is appropriate for very preterm infants but the more careful saturation targeting guideline should be considered to prevent hypoxemic events and hyperoxia.

• Korean Journal of Environmental Biology
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• v.27 no.4
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• pp.341-352
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• 2009

This study was carried out to investigated community structure of macrobenthic assemblages around the Wolseong Nuclear Power Plant, East Sea of Korea and seasonal sampling was performed from October 2007 to July 2008. A total of 163 macrobenthic fauna were collected. The overall average macrobenthos density and biomass were 1,005 individuals $m^{-2}$ and $21.81\;gWWt\;m^{-2}$, respectively. Based on the LeBris (1988) index, there were 10 dominant species accounting for approximately 69.00% of total individuals. The major dominant species were the polychaetes Spiophanes bombyx (349 inds. $m^{-2}$), Mediomastus californiensis (82 inds. $m^{-2}$), Sigambra tentaculata (55 inds. $m^{-2}$), Magelona japonica (50 inds. $m^{-2}$), Scoletoma longifolia (33 inds. $m^{-2}$) and the Unidentified amphipod (Amphipoda spp., 72 inds. $m^{-2}$). The conventional multi-variate statistics (cluster analysis and non-metric multi-dimensional scaling) applied to assess spatial variation in macrobenthic assemblages. Cluster analysis and nMDS ordination analysis based on the Bray-Curtis similarity identified 2 major station groups. The major group 1 was associated with sand dominated stations and was characterized by high abundance of the bivalves Mactra chinensis, Siliqua pulchella and the polychaete Protodorvillea egena. On the other hand, major group 2 was connected with mud dominated stations and was numerically dominated by the polychaetes M. californiensis, M. japonica, Sternaspis scutata, S. longifolia and the bivalves Thyasira tokunagai and Theora fragilis. However, macrobenthic community structure were no significant differences between the environmental variables (sediment type and depth) and heated discharge.

• Korean Journal of Poultry Science
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• v.36 no.3
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• pp.247-255
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• 2009

This work was conducted to investigate the effects of the addition level of Corn distiller's dried grains with solubles (CDDGS) and phytase in broiler diets on the broiler performance and the ileal amino acid digestibility. Three eighty four Ross broiler (one-day-old) were assigned randomly to 8 treatments groups (12 birds/pen, 4 pens/treatment) as $4{\times}2$ complex factors of CDDGS 4 treatments (0, 5, 10 and 15%) and phytase 2 treatments (0, 500 FTU/kg), and fed experimental diets for 6 weeks (starter, 0~2 wk; grower, 2~4 wk; finisher, 4~6 wk). After the feeding trial was finished, 12 broilers (6 weeks) with similar weights were selected from all treatments to investigate the digestibility of nutrients and amino acids for the first week. The experimental diets contained similar ME and CP of all treatments. Body weight gains and feed intakes were high at phytase treatments (P>0.05), but there was no difference in feed intake of the chicks. The amino acid digestibilities of diets were improved for iso-leucine, lysine, threonine, valine, aspartic acid, proline, serine and tyrosine (P<0.05). Finally, this work showed that growth performance and amino acid digestibility were improved by the addition of CDDGS and phytase in broiler diets.

• Radiation Oncology Journal
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• v.6 no.2
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• pp.183-194
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• 1988

Twenty five patients with histologically proven medulloblastoma received craniospinal radiotherapy (CSRT) at the Seoul National University Hospital from 1979 to 1984. The extent of tumor removal was biopsy only in 2 patients, partial in 18, and near total in 5. With orthogonal technique of CSRT, mainly 55Gy was delivered to the posterior fossa (PF), 40Gy to whole brain (WB), and 30Gy to whole spine (WS). And with AP; PA technique, 50Gy to PF, 45-50Gy to WB, and 36 Gy to WS. Complete remission was obtained in $84\%$ of patients. Among 21 CR's 10 failures were observed, thus total failure rate was $56\%$ (14/25). Of 14 faiure 13 had the primary failure, 11 failed in primary site alone, 1 failure was combined with ventricular seeding, and another 1 was combined with neck node metastasis. There was 1 isolated spinal failure. Actuarial overall survival rates at 3 and 5 years were $75\%$ and $54\%$, and disease-free survival rates were $58\%$ and $36\%$, respectively. Better 5 year disease-free survival was noted in patients with 55 Gy to the posterior fossa than those with 50Gy $(62\%\;vs\;17\%,\;p<0.05)$, in patients treated with orthogonal technique than those treated with AP:PA technique $(87\%\;vs\;12\%,\;p<0.05)$, and in patients with near total removal than those with partial or less removal of tumor $(56\%\;vs\;30\%,\;N.S.)$ Re-irradiation was not satisfactory No severe late sequelae was noted among the survivors. For the higher control of medulloblastoma, dose to posterior fossa should be at least 55Gy with orthogonal CSRT to small tumor burden. And dose reduction in the subarachnoidal spaces might be safe, but optimal dose to the subarchnoidal spaces should be determined by the thorough tumor staging before radiotherapy.

• Journal of Animal Science and Technology
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• v.55 no.1
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• pp.25-32
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• 2013

The purpose of this study was to investigate the effects of mustard, which contains allyl isothiocyanate, on ruminal fermentation and methane emission in vitro. To this end, diluted ruminal fluid(30ml) was incubated anaerobically at $39^{\circ}C$ or 6, 12, and 24 h with or without seeds or powdered mustard. Either mustard seed or powdered mustard was weighed and serially (0, 3.33, 5.00, 6.67, and 8.33 g/L) mixed with ruminal fluid. Ammonia-N was increased (P < 0.05) by mustard treatment in a dose dependent manner. Regardless of concentration or form, mustard increased (P < 0.05) total VFA content but decreased (P < 0.01) pH compared to control group. Molar proportion of acetate (A) was decreased (P < 0.05) whereas propionate (P) was increased (P < 0.05) by mustard treatment, thereby A:P ratio was decreased (P < 0.05) compared to control group. Total gas production was increased (P < 0.01) in a linear manner by mustard treatment compared to control group. There was no effect of mustard powder, except 8.33 g/L level at 6 h, on methane emission. However, at 24 h, methane emission was reduced (P < 0.05) by 4.77% and 11.54% with 6.67 g/L and 8.33 g/L of mustard seeds supplementation, respectively. Altogether, these results suggest that mustard seeds containing allyl isothiocyanate may reduce methane production without disturbing ruminal fermentation.

• 한국유가공학회:학술대회논문집
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• 2002.04a
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• pp.59-60
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• 2002

Edible films such as wax coatings, sugar and chocolate covers, and sausage casings, have been used in food applications for years$^{(1)}$ However, interest in edible films and biodegradable polymers has been renewed due to concerns about the environment, a need to reduce the quantity of disposable packaging, and demand by the consumer for higher quality food products. Edible films can function as secondary packaging materials to enhance food quality and reduce the amount of traditional packaging needed. For example, edible films can serve to enhance food quality by acting as moisture and gas barriers, thus, providing protection to a food product after the primary packaging is opened. Edible films are not meant to replace synthetic packaging materials; instead, they provide the potential as food packagings where traditional synthetic or biodegradable plastics cannot function. For instance, edible films can be used as convenient soluble pouches containing single-servings for products such as instant noodles and soup/seasoning combination. In the food industry, they can be used as ingredient delivery systems for delivering pre-measured ingredients during processing. Edible films also can provide the food processors with a variety of new opportunities for product development and processing. Depends on materials of edible films, they also can be sources of nutritional supplements. Especially, whey proteins have excellent amino acid balance while some edible films resources lack adequate amount of certain amino acids, for example, soy protein is low in methionine and wheat flour is low in lysine$^{(2)}$. Whey proteins have a surplus of the essential amino acid lysine, threonine, methionine and isoleucine. Thus, the idea of using whey protein-based films to individually pack cereal products, which often deficient in these amino acids, become very attractive$^{(3)}$. Whey is a by-product of cheese manufacturing and much of annual production is not utilized$^{(4)}$. Development of edible films from whey protein is one of the ways to recover whey from dairy industry waste. Whey proteins as raw materials of film production can be obtained at inexpensive cost. I hypothesize that it is possible to make whey protein-based edible films with improved moisture barrier properties without significantly altering other properties by producing whey protein/lipid emulsion films and these films will be suitable far food applications. The fellowing are the specific otjectives of this research: 1. Develop whey protein/lipid emulsion edible films and determine their microstructures, barrier (moisture and oxygen) and mechanical (tensile strength and elongation) properties. 2. Study the nature of interactions involved in the formation and stability of the films. 3. Investigate thermal properties, heat sealability, and sealing properties of the films. 4. Demonstrate suitability of their application in foods as packaging materials. Methodologies were developed to produce edible films from whey protein isolate (WPI) and concentrate (WPC), and film-forming procedure was optimized. Lipids, butter fat (BF) and candelilla wax (CW), were added into film-forming solutions to produce whey protein/lipid emulsion edible films. Significant reduction in water vapor and oxygen permeabilities of the films could be achieved upon addition of BF and CW. Mechanical properties were also influenced by the lipid type. Microstructures of the films accounted for the differences in their barrier and mechanical properties. Studies with bond-dissociating agents indicated that disulfide and hydrogen bonds, cooperatively, were the primary forces involved in the formation and stability of whey protein/lipid emulsion films. Contribution of hydrophobic interactions was secondary. Thermal properties of the films were studied using differential scanning calorimetry, and the results were used to optimize heat-sealing conditions for the films. Electron spectroscopy for chemical analysis (ESCA) was used to study the nature of the interfacial interaction of sealed films. All films were heat sealable and showed good seal strengths while the plasticizer type influenced optimum heat-sealing temperatures of the films, 130$^{\circ}$C for sorbitol-plasticized WPI films and 110$^{\circ}$C for glycerol-plasticized WPI films. ESCA spectra showed that the main interactions responsible for the heat-sealed joint of whey protein-based edible films were hydrogen bonds and covalent bonds involving C-0-H and N-C components. Finally, solubility in water, moisture contents, moisture sorption isotherms and sensory attributes (using a trained sensory panel) of the films were determined. Solubility was influenced primarily by the plasticizer in the films, and the higher the plasticizer content, the greater was the solubility of the films in water. Moisture contents of the films showed a strong relationship with moisture sorption isotherm properties of the films. Lower moisture content of the films resulted in lower equilibrium moisture contents at all aw levels. Sensory evaluation of the films revealed that no distinctive odor existed in WPI films. All films tested showed slight sweetness and adhesiveness. Films with lipids were scored as being opaque while films without lipids were scored to be clear. Whey protein/lipid emulsion edible films may be suitable for packaging of powder mix and should be suitable for packaging of non-hygroscopic foods$^{(5,6,7,8,)}$.