• Restorative Dentistry and Endodontics
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• v.42 no.4
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• pp.309-315
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• 2017

Objectives: This study assessed the effect of water storage on the flexural strength (FS) of low shrinkage composites. Materials and Methods: A total of 165 bar-shaped specimens ($2{\times}2{\times}25mm$) were fabricated of 2 low shrinkage composites (Filtek P90 [3M ESPE], GC Kalore [GC International]) and a conventional methacrylate-based composite (Filtek Z250 [3M ESPE]). The specimens were subjected to 3-point bending test at 6 time intervals, namely: immediately after curing, at 24 hours, 1 week, 1 month, 6 months, and 1 year following storage in wet and dry conditions. The FS of the specimens were measured by applying compressive load at a crosshead speed of 1.0 mm/min. Data was analyzed using 3-way analysis of variance (ANOVA) and Tukey's test. Results: Three-way ANOVA revealed significant interactions between time, type of composite, and storage condition (p = 0.001). Tukey's multiple comparison test revealed significant reductions in FS of all composites after 6 months and 1 year of storage in distilled water compared to dry condition. Conclusions: Filtek P90 showed the highest and GC Kalore showed the lowest FS after 1 year storage in distilled water. The immediate high strength of Filtek Z250 significantly decreased at 1 year and its final value was lower than that of Filtek P90.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.115-119
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• 1997

The chemical and microbial properties and acceptability of milk and soymilk inoculated with Bifidobacterium were studied at each storage time (0, 5, 10, 15, 20, 25, and 30 days). Soymilk, milk, low-heat milk, low-fat milk, non-fat dry milk with Bifidobacterium longum ATCC 15707 were incubated in a nitrogen-carbon dioxide atmosphere at $4^{\circ}C$ for 30 days. pH and acidity of all the samples were in the range of $pH\;6.6{\sim}pH\;6.9$ and $0.4%{\sim}0.55%$ for 30 days, respectively. The viable cell numbers in non-fat dry milk reached above $8.4{\times}10^9\;CFU/mL$ after 15 days. The glucose content in soymilk was $4.5{\times}10^{-2}{\sim}5.5{\times}10^{-2}\;mM$ at 10 days of storage. Milk and soymilk containing B. longum at $4^{\circ}C$ were found to be different in taste, odor, off-flavor at each storage time (0, 2, 4, 6, 8, and 10 days). Sensory scores indicated that milk containing bifidobacteria was poorly affected by the storage time, but milk at 4 days of storage was quite close in odor and off-flavor to milk with storage time 0. Soymilk containing bifidobacteria at 2 and 4 days of storage had significantly higher acceptability of taste than soymilk with storage time 0.

• Economic and Environmental Geology
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• v.45 no.1
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• pp.41-48
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• 2012

A theoretical $CO_2$ storage capacity is estimated on the southwestern continental shelf margin of Ulleung Basin, offshore Korea using 2D/3D multi-channel seismic and wellbore data acquired in the area over the two decades since the late 1980s. For the first time in Korea, the present study applies an efficiency factor to the capacity calculation, together with the other required parameters. For possible $CO_2$ storage volume estimation of the study area, we interpreted the seismic data in the Gorae area from 800 m to 3,000 m below the seafloor integrated with the well data, and identified five different seismic units; the limited depth interval is considered because of fluid state of $CO_2$ and tightness of the formation. The total volumes of each seismic unit were converted with a time-depth relation inferred from the checkshot surveys before the other required parameters including porosity and density were applied to compute the potential storage capacity. The accumulated possible storage volume from the five depositional units in the study area is estimated to be approximately 5,100 Mton ($P_{50}$). The approaches made in this study will be applied to the rest area of the basin and other continental shelves (i.e., Yellow Sea and northern part of East China Sea) in the next phase.

• Development and Reproduction
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• v.7 no.1
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• pp.9-13
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• 2003

A series of experiments were conducted to compare the effects of various diluents in cold storage on the sea urchin, Hemicentrotus pulcherimus sperm. Various diluents of glucose solutions, artificial sea water(ASW) and 50% ASW were used to store the sperm at 4$^{\circ}C$. The storage effect was evaluated using sperm activity index(SAI), survival rate of sperm and fertilization rate to egg. ASW and 1.2 M glucose were found to be better diluents which maintained high motility and survival rate of sperm f3r a storage period of 30 days. Optimal pH of diluent to store the sperm at 4$^{\circ}C$ is 7.0∼8.0. In order to keep high SAI and survival rate of sperm, addition of 400 ppm neomycin into the diluent revealed the best storage results.

• Korean journal of food and cookery science
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• v.27 no.1
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• pp.63-73
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• 2011

Cabbage (Baechu) Kimchi in its truncated form was placed in four different packing materials, Ny/PE/LLDP, OPP/AL/PE, PP and PET, and quality changes were observed during storage. Changes in pH and total acidity showed an x-shaped cross-curve as pH decreased and total acidity increased during storage. PP tray showed the slowest change at $5^{\circ}C$ with time. The pH was initially 6.25, but decreased to 4.12~4.16 at 20 days, and total acidity showed a 4 to 4.8-fold increase after 20 days of storage compared to the initial value. During storage at $5^{\circ}C$, total bacterial count and lactic acid bacterial count rapidly increased after 4 days. The total bacterial quantity decreased after a period of time and there were differences according to packaging material; OPP/AL/PE packaging showed the most dramatic decrease. Change in microbial count mostly followed a similar pattern to that of total acidity for all packaging materials. Changes in the color of Kimchi liquid, when examined by color index in $L{\cdot}b$/a form, rapidly decreased over time, similar to pH. Small Ny/PE/PP and OPP/AL/PE packages of Kimchi were examined for changes in free volume inside the packaging. After 13 days of storage at $5^{\circ}C$, the volume was 243 mL, but storage at $20^{\circ}C$ resulted in a volume of 372 mL, a more than 1.5-fold increase in free volume. There were changes in the quality characteristics of small package Kimchi according to storage temperature and packaging material, and large changes in pH, total acidity, and microbial count were evident upon storage at $5^{\circ}C$ for 8 days, which was the optimum palatability period. Mostly, PP treatment showed the slowest quality changes upon storage at $5^{\circ}C$. However, due to small package Kimchi's fast consumption system, the appropriate choice of packaging material must consider the product's turnover ratio. Further, the varieties of small package Kimchi should be diversified according to different consumer preferences by offering Kimchi with different maturity levels. Further, since the leading consumer base ranges in age from the teens to thirties, the development of various products targeting such consumers is necessary.

• Horticultural Science & Technology
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• v.19 no.2
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• pp.170-173
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• 2001

Postharvest diseases developed on harvested products result in a great economic loss. The objective of this research was to develop a chemical treatment to control major postharvest pathogens including Botrytis cinerea and Penicillium expansum in the cold storage room. Acetic acid ($2.4mg{\cdot}L^{-1}$, $4.8mg{\cdot}L^{-1}$) inhibits spore germination and mycelial growth of B. cinerea and P. expansum on PDA at room temperature ($25^{\circ}C$) and low temperature ($2^{\circ}C$). Fumigation of cold storage room with $SO_2$ ($5g{\cdot}m^{-3}$) gas or gaseous acetic acid ($4.8g{\cdot}m^{-3}$) prior to operation greatly reduced population of fungi in the cold storage room.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.3
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• pp.405-410
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• 2015

The objective of this study was to evaluate the effects of sequential applications of ${\varepsilon}$-polylysine (EPL) or lauramide arginine ethyl ester (LAE) sprays followed by an acidic calcium sulfate (ACS) spray on inoculated chicken carcasses to reduce Salmonella (Salmonella enterica serovars including Salmonella typhimurium and Salmonella enteritidis) contamination during 6 days of storage ($4.4^{\circ}C$). Secondly, reductions of the resident microflora were studied on uninoculated chicken carcasses following the sequential application of the treatments, chilling and 10 days of storage at $4.4^{\circ}C$. The treatment of Salmonella inoculated carcasses with 300 mg/L EPL followed by 30% ACS (EPL300-ACS30) sprays reduced Salmonella counts initially by 1.5 log cfu/mL and then by 1.2 log cfu/mL (p<0.05) following 6 days of storage at $4.4^{\circ}C$. Likewise, 200 mg/L LAE followed by 30% ACS (LAE200-ACS30) treatment reduced initial Salmonella counts on poultry carcasses by 1.8, 1.4 and 1.8 log cfu/mL (p<0.05), respectively, after 0, 3, and 6 days storage. Immediately after the treatments, EPL300-ACS30 and LAE200-ACS30 both reduced Escherichia coli counts significantly by 2.6 and 2.9 log cfu/mL, respectively. EPL300-ACS30 and LAE200-ASC30 were effective in lowering psychrotroph counts by 1 log cfu/mL on day 10 when compared to the control and distilled water treatments. This study demonstrated that EPL300-ACS30 and LAE200-ACS30 were effective in reducing Salmonella on inoculated chicken carcasses both after treatment and during the storage at $4.4^{\circ}C$ for up to 6 days. In addition, reductions in psychrotroph counts indicated that these treatments might have the potential to increase the shelf-life of poultry carcasses.

• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.3
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• pp.347-359
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• 2023

Objective: This study aimed to evaluate the suitability of polydeoxyribonucleotides (PDRN) as a storage medium for avulsed teeth. Materials and Methods: The viability of human periodontal ligament (PDL) cells stored in Hank's balanced salt solution and PDRN solutions (concentrations, 10, 25, 50, and 100 ㎍/mL) and tap water was measured using the Cell Counting Kit-8 and Live/Dead assays. In addition, Nitric oxide detection and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to evaluate the anti-inflammatory effect of PDRN. Results: The viability of PDL cells stored in a 100 ㎍/mL PDRN solution was significantly higher than that of cells stored in the other solutions (p < 0.01). Furthermore, cells stored in 100 ㎍/mL PDRN solution demonstrated a significantly reduced NO production (p < 0.0001), and cells stored in 50 and 100 ㎍/mL PDRN solutions expressed significantly lower levels of tumor necrosis factor α, interleukin (IL) -4, IL-6, and IL-10 (p < 0.01) compared to cells stored in HBSS. Conclusion: The PDRN solution exhibited cell-preserving and anti-inflammatory effects on the PDL cells. The findings of this study can serve as a basis for further experiments directed at the development of an effective storage medium for avulsed teeth.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.1
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• pp.113-118
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• 2006

The effects of dietary Rhus verniciflua Stokes supplementation (0%, 2%, 4% and 6%/feed) on meat color, water-holding capacity (WHC), lipid oxidation and fatty acid composition in m. longissimus from Hanwoo (Korean cattle) beef during refrigerated storage were investigated. The $L^*$, $a^*$, $b^*$ and $C^*$ values of 4% group were significantly (p<0.05) higher than those of the other groups for 7 days of storage. The $a^*$, $b^*$ and $C^*$ values declined gradually during storage in all of the groups and the decline was more rapid in control group. The metmyoglobin (%) was significantly (p<0.05) increased during storage time in all of the groups, but the 4% group had a lower rate of metmyoglobin accumulation during storage. WHC was significantly (p<0.05) higher in the 2% and 4% groups than in the other groups. The TBARS (thiobarbituric acid reactive substances) value of day 0 was not significantly (p>0.05) different among 4 diet conditions, but the TBARS value after 5 days of storage was significantly (p<0.05) higher in the control group than in other groups. The proportions of C18:1, MUFA, UFA and MUFA/SFA ratio were significantly (p<0.05) higher in the meat from Rhus verniciflua Stokes-supplemented Hanwoo than in the control group. Consequently, the meat from Rhus verniciflua Stokes-supplemented Hanwoo showed higher color stability, WHC, unsaturated fatty acids and retarded lipid oxidation compared to the control meat. In particular, dietary Rhus verniciflua Stokes supplementation with 4% extended storage life compared to the other groups.

• Journal of Ecology and Environment
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• v.29 no.1
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• pp.23-27
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• 2006

This study was conducted to evaluate forest carbon cycling and soil $CO_2$ efflux rates in a 42-year-old pine (Pinus densiflora) stand located in Hamyang-gun, Korea. Aboveground and soil organic carbon storage, litterfall, litter decomposition, and soil $CO_2$ efflux rates were measured for one year. Estimated aboveground biomass carbon storage and increment in this stand were $3,250gC/m^2\;and\;156gC\;m^{-2}yr^{-1}$, respectively. Soil organic carbon storage at the depth of 30 cm was $10,260gC/m^2$ Mean organic carbon inputs by needle and total litterfall were $176gC\;m^{-2}yr^{-1}\;and\;235gC\;m^{-2}yr^{-1}$, respectively. Litter decomposition rates were faster in nne roots less than 2 mm diameter size ($<220\;g\;kg^{-1}yr^{-1}$) than in needle litter ($<120\;g\;kg^{-1}yr^{-1}$). Annual mean and total soil respiration rates were $0.37g\;CO_2m^{-2}h^{-1}$ and $2,732g\;CO_2m^{-2}yr^{-1}$ during the study period. A strong positive relationship existed between soil $CO_2$ efflux and soil temperature (r=0.8149), while soil $CO_2$ efflux responded negatively to soil pH (r=-0.3582).