• Journal of Aquaculture
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• v.19 no.1
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• pp.52-56
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• 2006

This study was conducted to investigate the effects of three different concentrations (6%, 8% and 10% final volume) of dimethyl sulfoxide (DMSO) on cryopreserved sperm of grass carp (Ctenopharyngodon idellus). Grass carp sperm was suspended in Kurokura extender #2 and equilibrated at $4^{\circ}C$ for 10 min. French straws (0.25 ml) of sperm were frozen from $4^{\circ}C\;to\;-4^{\circ}C$ at a rate of $4^{\circ}C\;min^{-1}$ and then ken $-4^{\circ}C\;to\;-80^{\circ}C$ at a rate of $11^{\circ}C\;min^{-1}$. The straws were kept at $-80^{\circ}C$ for 10 min and finally stored in liquid nitrogen $(-196^{\circ}C)$. The cryopreserved sperm was thawed in a water bath at $40^{\circ}C$ for 30 sec and fertilization, hatching rate and larval malformation were compared with fresh sperm (control). The fertilization rate of post-thawed sperm was comparable (from 88.21% to 94.30%) to that of fresh sperm. However, hatching rate of all frozen sperm were significantly lower (P<0.05) than that of control. Additionally, the larval abnormality rate of frozen sperm was significantly higher than that of fresh sperm. The results indicate that DMSO could affect the quality of cryopreserved sperm of grass carp, and a freezing program and a proper extender composition should be further studied.

• Economic and Environmental Geology
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• v.30 no.6
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• pp.543-551
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• 1997

Poongjeon talc deposits is emplaced in dolomite and dolomitic limestone of the Cambro-Ordovician Samtaesan Formation. Ore in Poongjeon is low grade talc and the deposit has been known as the contact metasomatic or hydrothermal replacement type related to the intrusion of late Cretaceous granite in this area. X-ray diffraction, electron microprobe analysis, fluid inclusion and stable isotope analysis were utilized to examine the mineralogy of the ore and the origin of the ore fluid. The ore from Poongjeon mine mainly consists of talc and tremolite with minor amount of illite, vermiculite, smectite, and chlorite-vermiculite mixed layer. Occurrence of ore body indicates that the talc-tremolite ore was formed through the replacement by the $SiO_2$-rich hydrothermal fluid along the bedding and dike boundaries, or contact of amphibolite and basic dike with carbonate rocks. The temperature and pressure of the ore forming fluids at the time of the talc mineralization were estimated as $350^{\circ}C$ and 400 bar, respectively, based on the heating and freezing data of the fluid inclusions in quartz from talc-tremolite veins. During the talc-tremolite formation, fluids were divided into $CO_2$-enriched fluid and $CO_2$-poor fluid from $CO_2$ immiscibility (or effervescence). Oxygen isotope values (${\delta}^{18}O$) of the talc-tremolite fall within a range between 12.2 and 12.9‰. Hydrogen isotope values(${\delta}D$) of the ore range from -60 to -85‰ and $H_2O$ contents range from 2.0 to 3.4 wt.%. ${\delta}^{18}O$ and ${\delta}D$ values of talc ore indicate that the hydrothermal fluid involved in talc-tremolite formation was of igneous origin. Oxygen and hydrogen isotopic exchange between talc ore and the surface water was negligible after talc-tremolite ore formation.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.2
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• pp.227-233
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• 2007

The purpose of this research was to study the effects of the feeding of dietary citrus byproducts on the physicochemical properties and palatability of Hanwoo rump (HR). The samples for experimental samples consisted of the HR not fed without citrus byproducts pulp (CBP-0) and the HR rump fed with citrus byproducts pulp during the fattening period (CBP-1). The control (CBP-0) HR rump was fed by general practical feeding (roughages and concentrates were fed separately), while the CBP-1 was fed in the same manners as CBP-0 until 17 months but with citrus byproducts then fed fer the next 10 months. There were no significant differences in the $L^*$ (tightness), $a^*$ (redness) and $b^*$ (yellowness) of the HR between the CBP-0 and CBP-1 fed groups. There were no significant differences in the pH, VBN content and EDA between the samples, but the TBARS value of the CBP-1 fed group was lower than that of the CBP-0 fed group (p<0.05). There were no significant differences in the water holding capacity, freezing loss, thawing loss, boiling and roasting logs between the CBP-0 and CBP-1 fed groups. There were no significant differences in the hardness, cohesiveness, chewiness and shear force between the samples, but the springiness of the CBP-1 fed group was higher than that of the CBP-0 fed group (p<0.05). There were no significant differences in the sensory scores for the roasted beef between the CBP-0 and CBP-1 fed groups. There were no significant differences in the taste, flavor, juiciness and palatability of roasted beef the between samples, but the tenderness of the CBP-1 fed group was superior to that of the CBP-0 fed group.

• Food Science of Animal Resources
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• v.43 no.5
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• pp.840-858
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• 2023

This study was designed to compare the quality changes in mackerel fillets stored under different conditions by using hyperspectral imaging (HSI) techniques. Fillets packaged in vacuum were stored for six days under five different conditions: refrigerated at 4℃ (R group); iced at 5±3℃ (I group); kept at an ambient of 17±2℃ (A group); frozen at -18℃ for 24 h and thawed in a refrigerator at 4℃ for 5 h on the sampling day (FTR group); FTR thawed in tap water instead of thawing in a refrigerator (FTW group). The FTR group had the lowest total bacterial count, drip loss, 2-thiobarbituric acid reactive substances, volatile basic nitrogen, and texture profile analysis values among groups during the entire storage period (p<0.05). Scanning electron microscopy revealed that the FTR group had less damage, while the other groups had shrunken muscle tissues. HIS integrated with the partial least squares model yielded reliable and efficient results, with high R²_cv values, for several quality parameters of the mackerel fillets. Overall, the FTR group, involving freezing and thawing in a refrigerator, appears to be the most favorable option for maintaining the quality of mackerel fillets, which could be practically implemented in the industry. HSI is a suitable and effective technique for determining the quality of mackerel fillets stored under different conditions.

• Magazine of the Korean Society of Agricultural Engineers
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• v.26 no.3
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• pp.46-58
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• 1984

This study was carried out to investigate the compressive strength and the other effects varying to seasons and curing days on the wet curing conditions of the plain concrete. The results obtained are summarized as follows; 1. The longer the wet curing days and the higher the temperature, the greater the compressive strength was expected. 2.。$_2$8, compressive strength of concrete at 28 days under the dry curing conditions showed a range in 64-76% of that under the wet curing conditions. 3. The seasonal variations in the compressive strength under the wet curing showed in order of summer>spring=autumn>winter, and that under the dry curing were in order of spring ≒autumn> summer> winter. 4. In order to obtain 90% of the design compressive strength, 7 days in spring or autumn and 2 weeks of the wet curing in summer were required. 5. The compressive strength of concrete under the wet curing by using wet straw bag cover was almost the same as that of water curing method. 6. Under the wet curing conditions, the higher the temperature, the greater the effect of the curing of concrete was obtained, however, the compressive strength of concrete was decreased under relatively higher (over 15$^{\circ}$ C) and lower temperature (below 4$^{\circ}$C). 7. Freezing damage was occured when temperature was below 0$^{\circ}$ C and humidity was relatively high. 8. A considerable differnce between estimation of $^{\circ}$$_2$8 from $^{\circ}$7 and measured one was appeared in case of the dry curing conditions. Oregon formula was appeared to be acceptable under the wet curing conditions. 9. In relationship between $^{\circ}$$_2$8 and $^{\circ}$7~, $^{\circ}$28=1. 52 $^{\circ}$7 under the wet curing conditions except winter season, and $^{\circ}$$_2$8 =(1.39-1, 48)$^{\circ}$7 under the dry curing conditions were shown.

• Journal of Pharmaceutical Investigation
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• v.26 no.4
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• pp.299-308
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• 1996

In order to develop the controlled release of a drug from the suppsitories, in vitro drug release and in vivo absorption in rabbits were investigated. Various suppository forms with hollow cavities, into which drugs in the form of fine powder or solid dispersion system(SDS) could be placed, were utilized. The polyvinyl alcohol(PVA) hydrogel as a base, and propranolol HCl(PPH) as a model drug were employed. In vitro drug dissolution studies showed that the dissolved amounts(%) of PPH from PPH-methylcellulose(MC)-SDS and PPH-ethylcellulose(EC)-SDS reached 100% and 63% in 4.5-hours, respectively. In the relative strength test for PVA hydrogel, PVA hydrogel became harder and more rigid when the number of freezing-thawing cycles and the ratio of PVA 2000 were increased. In vitro drug release profile revealed that the release rate(%) of PPH from PPH-EC-SDS and PPH-MC-SDS hollow type suppositories were sustained. The release amount(%) of PPH from PPH-EC-SDS hollow type suppositories was not affected by storage time, but since the use of hydrophilic MC made PPH diffuse into the hydrogel after it absorbed the water of base, the various release patterns were appeared as the storage time went by. In vivo absorption experiments with rabbits showed that PPH-EC-SDS(PPH : EC=1:3) hollow type suppository delayed the absorption of PPH, significantly. The $C_{max}$, $AUC_{0{\rightarrow}8}$ and MRT of PPH powder hollow type suppository were $196.37{\pm}5.63\;ng/ml$, 1105.26 ng/ml/min and 8.66 min, respectively. The $C_{max}$, $AUC_{0{\rightarrow}8}$ and MRT of PPH-EC-SDS(PPH : EC=1:3) were $91.30{\pm]14.14\;ng/ml$, 554.69 ng/ml/min, 235.99 min, respectively.

• Food Science of Animal Resources
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• v.43 no.2
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• pp.245-268
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• 2023

The effects of phosphate alternatives on meat quality in marinated chicken were investigated with the application of chilling and freezing. Breast muscles were injected with solution of the green weight containing 1.5% NaCl and 2% sodium tripolyphosphate (STPP) or phosphate alternatives. Treatment variables consisted of no phosphate [control (-)], 0.3% sodium tripolyphosphate [control (+)], 0.3% prune juice (PJ), 0.3% oyster shell, 0.3% nano-oyster shell, and 0.3% yeast and lemon extract (YLE) powder. One-third of the meat samples were stored at 4℃ for 1 d, and the rest of the meats were kept at -18℃ for 7 d. In chilled meat, a lower drip loss was noted for control (+) and YLE, whereas higher cooking yield in YLE compared to all tested groups. Compared with control (+), the other treatments except PJ showed higher pH, water holding capacity, moisture content, lower thawing and cooking loss, and shear force. Natural phosphate alternatives except for PJ, improved the CIE L^* compared to control (-), and upregulated total protein solubility. However, phosphate alternatives showed similar or higher oxidative stability and impedance measurement compared to control (+), and an extensive effect on myofibrillar fragmentation index. A limited effect was observed for C^*, h°, and free amino acids in treated meat. Eventually, the texture profile attributes in cooked of phosphate alternatives improved except for PJ. The results indicate the high potential use of natural additives could be promising and effective methods for replacing synthetic phosphate in chilled and frozen chicken with quality enhancement.

• Journal of Embryo Transfer
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• v.31 no.4
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• pp.355-365
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• 2016

The cryopreservation of sperm has become the subject of research for successful artificial insemination technologies. Antifreeze proteins (AFPs), one of the factors necessary for effective cryopreservation, are derived from certain Antarctic organisms. These proteins decrease the freezing point of water within these organisms to below the temperature of the surrounding seawater to protect the organism from cold shock. Accordingly, a recent study found that AFPs can increase the motility and viability of spermatozoa during cryopreservation. To evaluate this relationship, we performed cryopreservation of boar sperm with AFPs produced in the Arctic yeast Leucosporidium sp. AFP expression system at four concentrations (0, 0.01, 0.1, and $1{\mu}g/ml$) and evaluated motility using computer assisted sperm analysis. DNA damage to boar spermatozoa was measured by the comet assay, and sperm membrane integrity and acrosome integrity were evaluated by flow cytometry. The results showed that motility was positively affected by the addition of AFP at each concentration except $1{\mu}g/ml$ (p<0.001). Although cryopreservation with AFP decreased the viability of the boar sperm using, the tail DNA analyses showed that there was no significant difference between the control and the addition of 0.1 or $0.01{\mu}g/ml$ AFP. In addition, the percentage of live sperm with intact acrosomes showed the least significant difference between the control and $0.1{\mu}g/ml$ AFP (p<0.05), but increased with $1{\mu}g/ml$ AFP (p<0.001). Our results indicate that the addition of AFP during boar sperm cryopreservation can improve viability and acrosome integrity after thawing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1566-1572
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• 2004

Effects of azodicarbonamide (ADA) were investigated on the rheological properties of flour dough by measuring farinogram, amylogram and extensogram based on the amount of ADA added. Quality characteristics of the bread made with the ADA added dough were also evaluated by measuring dough volume, moisture content, pH, proofed time, baking loss and textural characteristics. The farinogram showed that water absorption, stability and elasticity of the dough with ADA were higher than those without ADA. However, its absorption time and weakness decreased compared to the dough without ADA. Through the amylogram, it was found that gelatinization temperature and maximum viscosity increased, but temperature of maximum viscosity reduced in the dough with ADA. The extensogram showed that the area and resistance of the dough increased slightly but extensibility decreased drastically after fermentation, resulting in the ratio of resistance and extensibility (R/E) of the dough with ADA was lower than those without ADA. The bread prepared with the dough containing ADA after freezing up to 12 weeks showed higher pH and specific loaf volume but lower moisture content, second proof time and resistance than those without ADA.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.477-480
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• 2008

With an increase of power consumption due to industrial development, the generation of coal ash has been growing tremendously and, accordingly, environmental concern over its disposal and insufficiency in disposal sites have been raised as other issues to be considered. In order to examine the usability of coal ash as an aggregate for concrete, such fundamental information as slump, air contents, mechanical properties and durability of concrete has been secured by way of setting 10, 20 or 30 wt. % of fine aggregate alternative rate of ash and identifying its basic properties at each pond-ash contents. The results of the study indicate that slump and air content heavily depend on the site of generation, and this might greatly influence on the content of fine particles of the ash. It is also shown that its freezing and thawing resistance tends to be relatively lower than that of Plain, which requires comprehensive examination over next few years on the absorptiveness and properties of mixed water of the ash collected from each disposal site.