• Journal of Preventive Medicine and Public Health
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• v.29 no.4 s.55
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• pp.747-764
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• 1996

This study intended to obtain an useful information for health management of lead exposed workers and determine biological monitoring interval in early period of exposure by measuring the lead exposure indices and work duration in all male workers (n=433 persons) exposed less than 1 year in 6 storage battery industries and in 49 males who are not exposed to lead as control. The examined variables were blood lead concentration (PBB), Zinc-protoporphyrin concentration (ZPP), Hemoglobin (HB) and personal history; also measured lead concentration in air (PBA) in the workplace. According to the geometric mean of lead concentration in the air, the factories were grouped into three categories: A; When it is below $0.05mg/m^3$, B; When it is between 0.05 and $0.10mg/m^3$, and C; When it is above $0.10mg/m^3$. The results obtained were as follows: 1. The means of blood lead concentration (PBB), ZPP concentration and hemoglobin(HB) in all male workers exposed to lead less than 1 year in storage battery industries were $29.5{\pm}12.4{\mu}g/100ml,\;52.9{\pm}30.0{\mu}g/100ml\;and\;15.2{\pm}1.1\;gm/100ml$. 2. The means of blood lead concentration (PBB), ZPP concentration and hemoglobin(HB) in control group were $5.8{\pm}1.6{\mu}g/100ml,\;30.8{\pm}12.7{\mu}g/100ml\;and\;15.7{\pm}1.6{\mu}g/100ml$, being much lower than that of study group exposed to lead. 3. The means of blood lead concentration and ZPP concentration among group A were $21.9{\pm}7.6{\mu}g/100,\;41.4{\pm}12.6{\mu}g/100ml$ ; those of group B were $29.8{\pm}11.6{\mu}g/100,\;52.6{\pm}27.9{\mu}g/100ml$ ; those of group C were $37.2{\pm}13.5{\mu}g/100,\;66.3{\pm}40.7{\mu}g/100ml$. Significant differences were found among three factory group(P<0.01) that was classified by the geometric mean of lead concentration in the air, group A being the lowest. 4. The mean of blood lead concentration of workers who have different work duration (month) was as follows ; When the work duration was $1\sim2$ month, it was $24.1{\pm}12.4{\mu}g/100ml$, ; When the work duration was $3\sim4$ month, it was $29.2{\pm}13.4{\mu}g/100ml$ ; and it was $28.9\sim34.5{\mu}g/100ml$ for the workers who had longer work duration than other. Significant differences were found among work duration group(P<0.05). 5. The mean of ZPP concentration of workers who have different work duration (month) was as follows ; When the work duration was $1\sim2$ month, it was $40.6{\pm}18.0{\mu}g/100ml$, ; When the work duration was $3\sim4$ month, it was $53.4{\pm}38.4{\mu}g/100ml$ ; and it was $51.5\sim60.4{\mu}g/100ml$ for the workers who had longer work duration than other. Significant differences were found among work duration group(P<0.05). 6. Among total workers(433 person), 18.2% had PBB concentration higher than $40{\mu}g/100ml$ and 7.1% had ZPP concentration higher than $100{\mu}g/100ml$ ; In workers of factory group A, those were 0.9% and 0.0% ; In workers of factory group B, those were 17.1% and 6.9% ; In workers of factory group C, those were 39.4% and 15.4%. 7. The proportions of total workers(433 person) with blood lead concentration lower than $25{\mu}g/100ml$ and ZPP concentration lower than $50{\mu}g/100ml$ were 39.7% and 61.9%, respectively ; In workers of factory group A, those were 65.5% and 82.3% : In workers of factory group B, those were 36.1% and 60.2% ; In workers of factory group C, those were 19.2% and 43.3%. 8. Blood lead concentration (r=0.177, P<0.01), ZPP concentration (r=0.135, P<0.01), log ZPP (r=0.170, P<0.01) and hemoglobin (r=0.096, P<0.05) showed statistically significant correlation with work duration (month). ZPP concentration (r=0.612, P<0.01) and log ZPP (r=0.614, P<0.01) showed statistically significant correlation with blood lead concentration 9. The slopes of simple linear regression between work duration(month, independent variable) and blood lead concentration (dependent variable) in workplace with low air concentration of lead was less steeper than that of poor working condition with high geometric mean air concentration of lead. The study result indicates that new employees should be provided with biological monitoring including blood lead concentration test and education about personal hygiene and work place management within $3\sim4$ month.

• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.202-208
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• 2013

This study was conducted to investigate the effect of delayed controlled atmosphere (CA) storage on fruit quality and the incidence of storage disorders during CA storage of 'Fuji' apples (Malus x domestica Borkh.). In the first year of experiment, 'Fuji' apples showed 40% of watercore disorder at the commercial harvest time (Oct. 22). Twenty days delayed CA storage caused to develop the incidence of flesh browning while 30 days delayed CA storage did not. In the second year of experiment, watercore was increased with delaying harvest time. As the estabilishment of delayed CA storage was delayed, the incidence of flesh browning increased at 10 to 30 days delayed CA storage but 40 days delayed CA storage did not have any flesh browning incidence. Respiration rate increased with extending the storage duration. Delayed CA storage reduced respiration rate but was not different compared to the rapid CA. Ethylene production rate was lower in delayed CA storage than in cold storage but higher in delayed CA storage, compared to rapid CA storage. Titratable acidity was lower in delayed CA storage as CA storage progressed. Firmness was not different between rapid CA storage and delayed CA storage after 8 months of CA storage. Therefore, the results indicate that delayed CA storage should be a promising approach to reduce the risk development of flesh browning and watercore during CA storage of 'Fuji' apples.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.3
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• pp.147-151
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• 2006

Although various automated CBC analyzers with different WBC analytical principles were consequently introduced to clinical laboratory, the specific information concerning the suitability or unsuitability of aging samples is scarce. For this reason, we studied the effect of storage duration and temperature on CBC parameter in SE-9000 (SYSMEX Medical Electronics Co., Ltd., Kobe, Japan), automated CBC analyzer. We tested 32 K3-EDTA specimens with SE-9000 during 72 hours. Specimens were kept at room temperature (RT) and refrigerated and were analyzed at 0 hr, 4 hr, 8 hr, 24 hr, 48 hr and 72 hr after the collection of the specimens. The percentage changes from initial value for each parameters were calculated. Among the CBC parameters, hemoglobin, red blood cell count, mean corpuscular hemoglobin and platelets were stable for the study period at both temperatures. The mean corpuscular volume (MCV), hematocrit (Hct) and red cell distribution (RDW) increased and the mean corpuscular hemoglobin concentration (MCHC) decreased over time at room temperature. These parameters were stable when refrigerated. The leukocyte count was stable during 72hr at RT and when refrigerated. At room temperature, the relative percentages of neutrophils tend to increase, whereas those of lymphocyte and monocytes tend to decrease after 48 hours. When refrigerated, those of neutrophils and monocytes tend to increase, whereas those of lymphocytes tend to decreased over time. CBC parameters of refrigerated specimen were reliable for 72 hr for the exception of differential count from 24 hr but many CBC parameters, such as MCV, Hct, MCHC, RDW and differential count of leukocyte of blood stored at room temperature for 24 hr were unreliable.

• Korea-Australia Rheology Journal
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• v.21 no.2
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• pp.127-133
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• 2009

Hemorheological results may be influenced by the time between blood sampling and measurement, and storage conditions (e.g., temperature, time) during sample delivery between laboratories may further affect the resulting data. This study examined possible hemorheological alterations subsequent to storage of rat and dog blood at room temperature ($22^{\circ}C$) or with cooling ($4{\sim}10^{\circ}C$) for 2, 4, 6, 24, 48 and 72 hours. Measured hemorheological parameters included hematological indices, RBC aggregation and RBC deformability. Our results indicate that marked changes of RBC deformability and of RBC aggregation in whole blood can occur during storage, especially for samples stored at room temperature. The patterns of deformability and aggregation changes at room temperature are complex and species specific, whereas those for storage at the lower temperature range are much less complicated. For room temperature storage, it thus seems logical to suggest measuring rat and dog cell deformability within 6 hours; aggregation should be measured immediately for rat blood or within 6 hours for dog blood. Storage at lower temperatures allows measuring EI up to 72 hours after sampling, while aggregation must be measured immediately, or if willing to accept a constant decrease, over 24~72 hours.

• Journal of Biosystems Engineering
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• v.43 no.4
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• pp.401-409
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• 2018

Decay of fruit is one of the greatest issues in fruit storage. Purpose: In this study, citrus sterilization was performed to evaluate a dry sterilization method using an atmospheric-pressure nonthermal plasma treatment based on a dielectric-barrier discharge technique. Methods: Citrus samples were stored under four different environmental conditions as follows: group A had cold storage with plasma treatment with a temperature of $6.2{\pm}1.0^{\circ}C$ and relative humidity (RH) of $93.4{\pm}8.2%$, group B had ambient-temperature storage with $22.9{\pm}2.3^{\circ}C$ and $82.1{\pm}4.5%$ RH, group C ambient-temperature storage with plasma treatment with $25.3{\pm}2.2^{\circ}C$ and $90.0{\pm}2.8%$ RH, and group D had cold storage with $5.7{\pm}1.0^{\circ}C$ and $93.4{\pm}6.5%$ RH. Results: As a result of citrus surface sterilization by plasma treatment, treatment groups A and C together showed an average of 16.1 CFU/mL of mold colonies, while control groups B and D showed an average of $2.2{\times}10^2CFU/mL$ or approximately 13 times greater than the treatment groups. Regarding the mean concentration of aerobic bacteria colonies, the treatment groups (A and C) and control groups (B and D) showed an average of 7.1 CFU/mL and $1.9{\times}10^3CFU/mL$, respectively. This is approximately a 270-fold difference in the concentration of pathogen colonies between treatment and control groups. Conclusions: The results showed the potential of nonthermal plasma treatment for citrus storage in enhancing storage duration and quality preservation.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.202-208
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• 2006

Since abnormal fermentation and short storage duration of oriental melon are the main problems causing loss in commercial value, it is necessary to develop a food processing method using uncommercial melon. In this study, we suggested the effective pretreatment and storage conditions of melon as the material for alcoholic beverage production. Abnormally fermented melon had smaller carbohydrate and larger moisture content than normal one, indicating that carbohydrate in normal melon was probably converted to fermented products during fermentation. The sugar content of oriental melon was increased after fruiting and the highest value $(12.4^{\circ}Brix)$ was found at 5 weeks of storage. The maximum storage duration of normal and fermented oriental melons were 25 and 7 days at $4^{\circ}C$, and 8 and 4 days at room temperature, respectively. The oriental melon for fermentation-use could be conserved after slicing for 30 days at $4^{\circ}C$ with the addition of 1.5% citric acid and for one year at $-20^{\circ}C$ with the plastic film sealing, respectively.

• Food Science of Animal Resources
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• v.34 no.5
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• pp.683-691
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• 2014

The effects of sucrose stearate at various concentrations (0.1%, 0.2%, and 0.3%, w/v) on the physico-chemical characteristics of ready-to-eat (RTE) Samgyetang were investigated during storage at $25^{\circ}C$ for 12 mon. Over the storage duration, the addition of sucrose stearate had no significant effects on the proximate composition of Samgyetang, including meat, broth, and porridge, or the hardness and spreadability of the porridge, although it resulted in significantly higher CIE $L^*$ values for the porridge. The CIE $L^*$ values of Samgyetang porridge with added sucrose stearate increased until 9 mon, while the control decreased until 6 mon, and the values for both changed insignificantly thereafter. The breast meat of Samgyetang treated with sucrose stearate showed higher percentages of polyunsaturated fatty acid after 3 mon and lower percentages of monounsaturated fatty acid after 6 mon compared to the control (p<0.05), while no significant differences were observed with the different sucrose stearate concentrations (p>0.05). The overall sensory acceptability scores were higher at sucrose stearate concentrations of 0.2% or 0.3% after 6 mon and at 0.1% after 9 mon compared to those of the control.

• Journal of the Semiconductor & Display Technology
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• v.8 no.1
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• pp.13-17
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• 2009

In PRAM applications, the devices can be made for both binary and multi-state storage. The ability to attain intermediate stages comes either from the fact that some chalcogenide materials can exist in configurations that range from completely amorphous to completely crystalline or from designing device structure such a way that mimics multiple phase chase phenomena in single cell. We have designed stack-structured phase change memory cell which operates as multi-state storage. Amorphous $Ge_xTe_{100-x}$ chalcogenide materials were stacked and a diffusion barrier was chosen for each stack layers. The device is operated by crystallizing each chalcogenide material as sequential manner from the bottom layer to the top layer. The amplitude of current pulse and the duration of pulse width was fixed and number of pulses were controlled to change overall resistance of the phase change memory cell. To optimize operational performance the thickness of each chalcogenide was controlled based on simulation results.

• Solar Energy
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• v.14 no.2
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• pp.3-16
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• 1994

The major objectives of the study are to suggest the optimal basic design conditions for the horizontal storage tank system. For this purspose computer simulation has been carried out to find the characteristics of flow patterns in horizontal storage tank, and experiments have been carried out for the duration of one turnover, Experimental parameters are volume flow rate(1 LPM to 4 LPM), amount of heat generated from heat sources(0 W to 100 W), and inlet and outlet port types of the storage tank(DD type, DO type, ID type, IO type).

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.6
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• pp.685-691
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• 1998

In the first of two experiments, chemical composition (Ash, CP and CF contents), nutritive value (in vitro organic matter disappearance "lVOMD" and energy content "ME") and nitrogen retention of chopped date fronds (CDF) as affected by chemical treatment (CT) and storage duration (SD) were investigated. The experimental design was a completely randomized block, arranged in a $3{\times}4$ factorial, with 3 (CT) and 4 (SD) as the main factors using 2 replications / treatment. Three chemical treatments, were used : Control (With zero or no chemical treatment); treatment with 4% urea solution (w /w) and treatment with 4% urea + Date syrup extract (DS). The 4 (SD) were: Control (immediately after opening - without any storage or zero time storage); one month storage period; two months storage period and three months storage period. Both (CT) and (SD) had significant effects (p < 0.05) on CP and ash contents of the CDF, however there were no significant effects (p > 0.05) due to (CT) and (SD) on CF and nutritive value. High retention value (> 80%) for nitrogen was reported for the treated CDF, immediately after opening the incubated material (zero SD). However, nitrogen retention decreased with increasing (SD) to 67% after one month (SD) but tended to stay at a fairly constant level of 67% until 3 months of storage. In experiment 2, the feeding value of treated CDF was evaluated in comparison to Rhodes grass hay, using growing goats and sheep. A $4{\times}2$ factorial design was used (Four roughage sources were used : Rhodes grass hay, untreated CDF, urea-treated CDF and CDF treated with urea + DS with sheep and goats as two animal species, using three animals / treatment). Untreated CDF had a similar feeding value to Rhodes grass hay. However treatment of CDF with urea alone or with urea + DS depressed animal performance of both goats and sheep, apparently due to depression of feed intake (appetite). Feeding untreated CDF decreased feeding cost by 29% and cost/kg gain by 23%. CDF showed a good potential as a cheap local roughage and emergency feed for ruminants in the Sultanate.