• Analytical Science and Technology
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• v.36 no.2
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• pp.80-88
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• 2023

Fingerprints play a crucial role in the identification of potential suspects in criminal cases. However, determining the actual time, i.e., the time at which the fingermark was deposited, is challenging. Herein, we investigated the persistence and aging of fingerprints over time by observing the time evolution of latent fingerprints on a polystyrene box stored in a dark room. Fingerprint samples that were stored for up to two years could be detected with maximum accuracy using a black iron-oxide-based emulsion (black emulsion). To estimate the time of fingerprint deposition, fingerprint aging was studied by analyzing the lipid components of the fingerprints after their development. Cholesterol and squalene were selected as indicators of fingerprint aging, and their ratio was estimated to assess aging. In the case of fingerprint samples stored in a dark room for up to one month after deposition, the cholesterol/squalene ratio was approximately 0.01; it increased gradually to ≥ 0.1 over six months. A substantial reduction in the levels of cholesterol and squalene from the initial levels was also noted. Cholesterol and squalene were not detected after one year of storage. Thus, the extent of aging could be determined by analyzing the aging indicators for up to six months. Two cases that could cause error in the estimation of the fingerprint deposition time, namely, heating of the fingerprint sample before development and storage of the developed fingerprints in a dark room, were also investigated.

• Food Science of Animal Resources
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• v.38 no.5
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• pp.995-1007
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• 2018

Changes in the physicochemical properties of ready-to-feed liquid infant formula (LIF) stored at different temperatures (10, 20, 30, and $40^{\circ}C$) for 6 mon, focusing on 5-hydroxymethylfurfural (HMF) content, color, pH, fat globule size distribution, and rheological properties were determined. The HMF content increased with storage time, and LIF stored at $40^{\circ}C$ had a higher HMF content than that of LIF stored at $10^{\circ}C$. The lightness ($L^*$) decreased while redness ($a^*$) and yellowness ($b^*$) increased with increasing HMF content. The fat globule size and pH of LIF stored at $10^{\circ}C$ did not change. However, in the case of LIF stored at $30^{\circ}C$ and $40^{\circ}C$, the fat globule size increased and the pH decreased during storage for 6 mon. LIF stored at $40^{\circ}C$ had a higher apparent viscosity (${\eta}_{a,10}$) than that of LIF stored at $10^{\circ}C$, and the shear-thinning behavior of LIF stored at higher temperature was stronger than that of LIF stored at low temperature. The physicochemical changes of LIF during storage were accelerated by Maillard reaction (MR) at higher storage temperatures. Therefore, even if LIF is aseptically manufactured, we recommend that sterilized LIF should be stored at low temperature in order to minimize quality changes during storage.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.1
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• pp.21-29
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• 2004

Statement of problem : Because dental impression can be a cross-infection source, disinfection, such as immersion disinfection is nessecary. However, the disinfection process may change the volume of the impression cast. Purpose : The purpose of this study is to find out the effects on dimensional change of different storage times and methods, of agar-alginate impression when immersed in a 5% idophor disinfectant. Material and Methods : An agar-alginate impression was made from a mandible model and then was disinfected and stored according the experimental conditions and a stone model was produced. Measurements were taken between reference points on the original mandible model and they were compared to measurements taken between reference points on the stone model. The study was divided into 4 groups. In group 1, the impression was stored in a 100% humidor for 30 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 6 hours, 12 hours and 24 hours and stone models were made at each time. In group 2, the impression was immersed in 5% idophor disinfectant and then stored in a 100% humidor for the same length of times as group 1, and stone models were made at each time. In group 3, the impression was stored in extend-A-pourR, a special storage solution for 30 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 6 hours, 12 hours, 24 hours 3 days, and 7 days and stone models were made at each time. In group 4, the impression was immersed in 5% idophor disinfectant and then stored in stored in extend-A-pourR, a special storage solution for the same length of times as group 3, and stone models were made at each time. 5 impressions and stone models were made at each time to make a total of 180. The Student-t test (P < .05) was used to do a statistical analysis of the measurements of the mandible model and stone models. The repeated-measure 2-way analysis of variance (P < .05) was used to do a statistical analysis of the difference in the 4 groups. Results : The percent liner dimensional change was from $0.25{\pm}0.03%$ (group 1, 30 minutes) to $0.34{\pm}0.06%$ (group 4, 7 days). No significant change was noticed between the 4 groups. Conclusion : According to the above study, in both methods, least dimensional change was recorded when the storage times were short and in both methods, immersion in 5% idophor disinfectant did not effect dimensional change in the agar-alginate impression.

• The Journal of Advanced Prosthodontics
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• v.8 no.4
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• pp.296-303
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• 2016

PURPOSE. The aim of this study was to evaluate whether there is any typical deformation pattern existing in complete denture when it was dried by using the 3D scanner and surface matching program. MATERIALS AND METHODS. A total of 28 denture bases were fabricated with heat curing acrylic resin (each 14 upper and lower denture bases), and 14 denture bases (each 7 upper and lower denture bases) were stored in the water bottle (water stored), and another 14 denture bases were stored in the air (dry stored). Each specimen was scanned at $1^{st}$ day after deflasking, $14^{th}$ day after deflasking, and $28^{th}$ day after deflasking, and digitalized. Three dimensional deformation patterns were acquired by comparison of the data within storage group using surface matching program. For evaluating differences between groups, these data were compared statisticallyusing Kruskal Wallis and Mann Whitney-U test (${\alpha}$=.05). RESULTS. When evaluating 3D deformation of denture base, obvious deformations were not found in maxillary and mandibular water storage group. However, in dry stored group, typical deformation pattern was detected as storage time passes. It occurred mostly in first two weeks. Major deformations were found in the bilateral posterior area in both maxillary and mandibular group. In maxillary dry stored group, a statistical significance was found. CONCLUSION. It was proved that in both upper and lower denture bases, dry storage caused more dimensional deformation than water storage with typical pattern.

• Journal of the Korean Home Economics Association
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• v.42 no.1
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• pp.167-180
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• 2004

This study was carried out to investigate quality characteristics of chopped garlic stored at various temperature. Chopped garlic was stored at room temp.($25^{\circ}C$), refrigerator temp.($5^{\circ}C$) and frozen temp. ($-18^{\circ}C$) for 1, 2, 4, 8, 24, 48, 72 hours(room temp.) and 1, 3, 5, 7, 10, 15, 20, 30 days(refrigerator temp. and frozen temp.), respectively. Brown color, Hunter color value, vitamine C contents and flavor patterns by electronic noes of chopped garlic were measured. Fresh chopped garlic was used as control and garlic powder by hot air drying was used for comparisons. Brown color of chopped garlic increased with increasing storage time, and the intensity of that was reduced as following order such as chopped garlic stored at room temp., refrigerator temp. and frozen temp. Brown color of garlic powder was most dark amomg all the samples. The results of Hunter color value was consistent with then of brown color in chopped garlic, whereas those of garlic powder showed relatively low browning. Above results might be caused by the difference of measurement as only surface color was measured in Hunter color value unlike brown color. Vitamine C contents of chopped garlic decreased with increasing storage time, and in particular those stored at room temp. decreased markedly as retention of those stored at room temp. was 60％ of control after 1 day storage. Vitamine C retention of chopped garlic stored at refrigerator temp. was 78％ of control after 10 day storage and that stored at frozen temp. was 86％ of control after 30 day storage. At room temp., flavor pattern by electronic nose showed a difference between chopped garlic stored for 1hour and control, and showed occurrence of off odor after 1 day storage. Flavor pattern of garlic powder by electronic nose showed a mild flavor. Flavor patterns of chopped garlic stored at refrigerator temp. were similiar until 10 day storage, whereas those showed occurrence of volitile components after 15 day storage. Flavor patterns of chopped garlic stored at frozen temp. were similiar after 30 day storage, and especially those after 3 day storage were almost the same as control. Therefore it is desirable to store chopped garlic within 1 day at room temp. and within 10 days at refrigerator temp. And it is most desirable to store chopped garlic at frozen temp. as retention of quality characteristics was superior than other storage temp.

• Journal of the Korean Home Economics Association
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• v.18 no.4
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• pp.87-94
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• 1980

This study was carried out to make a comparison between iced and partial freezing of bastard, yellow tail, poragy, pomfret that were generally used for Sashimi and the results that measured k-value, VB-N, TMA-N were measured and the results are as follows : 1. Regardless of the kinds of fish, freshness is better preserved in partial freezing than in iced storage. 2. In Bastard, Yellow tail When iced its freshness estimation index its K-value rose above 20% after 4 days of storage. When stored partially frozen, its K-value reached 20% after 8 days. 3. Porgy when iced, its K-value reach 20% after 6 days of storage. But when stored partially frozen, its K-value could be prolonged until 9 days with same degree. Porge was preserved for the longest time among the four fishes. 4. Pomfret When iced during 4 days and stored partially frozen during 6 days, their K-value reached about 20% Pomfret was preserved for the shortest time among the four fishes. 5. According to the kinds of fish, the results that measured VB-N, TMA-N, total bacteria have some differences, but the method of partial freezing was superior to iced storage.

• Korean Journal of Poultry Science
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• v.28 no.3
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• pp.225-229
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• 2001

This experiment was carried out to investigate the effects of storage temperature and time on hatch-ability of the commercial Ross broiler breeder eggs. In Trial 1,720 eggs collected in the morning were allotted to four storage time treatments (3, 5, 7 and 9 days), with three replicates per treatment. The storage temperature was fixed at $4^{\circ}C$. In Trials 2 and 3, similar protocol was used as in Trial 1 except that the storage temperature was fixed at $17^{\circ}C$ and $28^{\circ}C$respectively. In Trial 1, hatchability was significantly (P<0.05) reduced when the eggs were stored more than 3 days. In Trial 2, no significant difference was found among all treatments, indicating that, at 17$^{\circ}C$ storage temperature, the eggs could be stored up to 9 days without reducing hatchability. In Trial 3, however, hatchability of eggs stored for 9 days was significantly reduced compared to the other treatments. In conclusion, we found out that optimum hatchability can be achieved with a storage temperature of $17^{\circ}C$ for Ross broiler eggs stored for up to 9 days.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.05a
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• pp.327-330
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• 2003

In this paper, a viscoelastic structural analysis for the spent pressurized water reactor(PWR) nuclear fuel disposal canister is carried out to predict the collapse of the canister while the canister is stored in a deep repository for long time. There may exist some subterranean heat in a deep repository while the nuclear fuel disposal canister is stored for long time. Then, a time-dependent viscoelastic structural deformation may occur in the canister due to the subterrnean heat Hence, the viscoelastic stress variation according to time should be computed to predict the structural strength of the canister. A viscoelastic material model is adopted. Analysis results show that even though some subterrnean heat may exist for quite a long time, the canister structure still endures stresses below the yield strength of the canister. Hence, some subterranean heat cannot seriously affect the structural strength of the canister.

• Food Science and Preservation
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• v.5 no.2
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• pp.111-117
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• 1998

Biochemical property changes of garlic during various storages and marketing after storage were investigated. Content of enzymatic pyruvic acid increased by room and low temperature storage but decreased by CA and MA storage. Fructan contents decreased rapidly by low temperature storage, but restrained decrement by CA and MA storage. Free sugar increased during storage, but did slowly by room temperature storage. Green pigment development was observed when garlics stored for 90days at low temperature were processed into crushed form. This discoloration was small for garlics stored in CA and MA, and never occurred for room temperature stored garlics. When marketed after storage, content of enzymatic pyruvic acid decreased in garlic stored in room and low temperature storage, but increased in garlics which decreased during CA and MA storage. Fructan contents deceased but free sugar contents continuously increased with marketing period. Green pigment development decreased in crushed garlic after 30days at room temperature marketing, but increased in low temperature marketing with marketing time progress.

• Journal of the Korean Society of Food Culture
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• v.19 no.1
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• pp.30-42
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• 2004

In order to examine the effect of the combination of fermented temperature and time on Baechu kimchi in a kimchi refrigerator, Baechu kimchi was fermented at four different modes of the fermentation temperature and time for 16 weeks and analyzed the properties of Baechu kimchi. The pH, Baechu kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ and Baechu kimchi fermented at $5^{\circ}C$ for 6 days/stored at $-1^{\circ}C$, decreased rapidly during first week and then decreased very slowly. The hardness and the chewiness of Baechu kimchi fermented at high temperature were higher and the values were decreased when the fermentation continued. In sensory evaluation, carbonated flavor in Baechu kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ was the best after 4 weeks, and Baechu kimchi fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$ was the best after 8 weeks. The scores for sourness were the highest on 8 weeks and 12 weeks in kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ and fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$, respectively. The sensory scores for overall acceptability were the best on 4 weeks and 8 week in kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ and fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$, respectively. Total microbial count was increased as the temperature of fermentation increased. Counts of Leuconostoc spp. reached to the highest after 6 days and counts of Lactobacillus spp reached to the highest after 5 days in kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$. From these results, it was concluded that it required 4 weeks to eat most edible Baechu kimchi in kimchi refrigerator fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$, and 8 weeks to eat most edible Baechu kimchi in kimchi refrigerator fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$.