• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.3
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• pp.299-309
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• 2014

When using an automotive heating, ventilation, and air conditioning (HVAC) system, we can obtain fresh outside air while maintaining the interior vehicle temperature. In this study, a correction equation considering experimental data for automotive indoor air leakage is defined to simulate the ratio of fresh air to recirculated air in the automobile cabin. With this correction equation, numerical results are compared with experimental data and validated. The $CO_2$ concentration in the automotive cabin is evaluated by considering various boarding conditions and mass flow rates of the HVAC system. The $CO_2$ concentration model derived in this study is expected to be used to control the effective air conditioning and become a basic research tool for automotive air quality control system development.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.273-278
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• 1998

Carbohydrate metabolism and partitioning are dependent on relationships between sources and sinks which can be affected by rates of photosynthesis and respiration. Fructan, the major form of stored carbohydrate in tall fescue (festuca arundineacea Schreb.), changes in concentration during growth and in response to the environment. Objectives of this study were i) to examine the content and the composition of carbohydrates in five tissues (mature leaf blade, immature leaf blade, leaf elongation zone, terminal meristem, and root tips) of two tall fescue genotypes, one with high yield per tiller (HYT) and one with low yield per tiller (LYT), and ii) to compare the reserved and utilized carbohydrates among above five different tissues, particularly between the leaf elongation zone and root tips. The established vegetative tillers of the HYT and LYT genotypes were grown in a controlled-environment growth chamber. Water-soluble carbohydrate (WSC) in the leaf elongation zone was about 22% of dry weight in the HYT and about 19% in the LYT genotype. The root tip also had high WSC, about 12% of dry weight in the HYT and 6% in the LYT genotype. Hexoses and sucrose were the major components of total WSC in all tissues except the leaf elongation zone. The growing tissues (sinks), i.e., the leaf elongation zone and root tip, had a high proportion of low degree of polymerization fructan, i.e., 3 to 8 hexose units.

• Journal of Applied Biological Chemistry
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• v.48 no.4
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• pp.187-192
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• 2005

Influence of herbicide oxadiazon on soil microbial activity and nitrogen dynamics was evaluated. Soil samples were treated with oxadiazon at field and tenfold field rates and incubated. Organic amendment was added as an additional substrate for soil microorganisms. Tenfold field rate oxadiazon stimulated substrate-induced respiration (SIR) and dehydrogenase activity (DHA) in amended soil as compared to unamended soil and control treatment. Soil urease activity was not affected by oxadiazon treatment. In both amended and unamended soils, treatment of the herbicide at higher rate had not significant influence on $NH_4$-N and $NO_3$-N concentrations. Higher dose of oxadiazon was degraded in both soils, but dissipation rate in amended soil was higher than unamended soil, with half-lives ($t_{1/2}$) of 23.1 and 138.6 days, respectively. Recommended field rate did not affect microbial activity and nitrogen dynamics in soil ecosystem. Results showed influence of oxadiazon on cycling processes of nitrogen in soil was not significant however its effect on microbial activity was a tendency depending on addition of organic amendment to soil.

• Journal of Ginseng Research
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• v.8 no.1
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• pp.65-74
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• 1984

This experiment was carried out to study the effects of light intensity and soil water regimes on the growth of ginseng seedling. The results were as follows: 1. The maximum light intensity and optimum temperature in 1,le photosynthesis of ginseng seedling were 10,000 lux and 23 $^{\circ}C$. Respiration rate was increased at high temperature. 2. Air and soil temperature under the shading were increased as the increase of light intensity but soil water contents were decreased as the increase of light intensity, whereas air and soil temperature were decreased as the increase of precipitation under the shade b5: soil water contents were increased as the increase of precipitation under the shade. 3. The higher the transmittance of the shade, the greater the specific leaf weight (S.L.W.) and stomatal density. In contrast, however, the contents of total chlorophyll, chlorophyll a and b, and stomatal length was decreased. There was no any significant difference light intensity of the a/b ratio of chlorophyll. 4. The highest photosynthesis was occurred in ginseng leaves grown under the shade 5% L.T.R. and net photosynthesis rates increased with increasing soil water contents. 5. Optimum condition for usable seedling yield were 5% L.T.R. and 3.3% precipitation under the shade. Useless seedling increased with increasing precipitation under the shade.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.4
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• pp.350-352
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• 1988

This study was carried out to know the influence of turbidity of submerged water on photosynthetic rate of rice plant after water submerging treatment. Rice plants were transplanted in the pot at maximum tillering stage and they were sumberged for 3days at meiotic stage, 20days after transplanting, in the plastic container which had the clear and turbid water temperature adjusted around 24 to $25^{\circ}C$. Photosynthetic rate at 6 hours recovery after submergence was 41.5 to 54.2% compared to the control, but in the case of cultivar 'Nagdongbyeo', it was rapidly increased by 97.3 to 104.6% in the clear water and by 68.6 to 77.5% in the turbid water at 2 to 4 days recovery after submergence. Photosynthetic rates per plants at 6 hours to 4 days recovery after submergence were 128.3 to 245.5 $C_2$ mg.hr.$^{-1}$, in 'Samgamgbyeo' and 71.1 to 162.4 $CO_2$, mgㆍhr.$^{-1}$ in 'Nagdongbyeo' Photosynthetic rate to respiration ratio of rice plant recovery after submergence was lower compared to control plant and it was lower in 'Nagdongbyeo' than that in 'Samgangbyeo'.ngbyeo' than that in 'Samgangbyeo'.gangbyeo'.pos;.

• Tuberculosis and Respiratory Diseases
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• v.83 no.2
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• pp.116-121
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• 2020

Particulate matter (PM) is suspended dust that has a diameter of <10 ㎛ and can be inhaled by humans and deposited in the lungs, particularly the alveoli. Recent studies have shown that PM has an adverse effect on respiratory diseases. The aim of this article is to review respiratory diseases associated with PM. According to existing studies, PM is associated with chronic obstructive pulmonary disease, bronchial asthma, and several other respiratory diseases and increases the mortality rates of these diseases. Moreover, increased exposure in the high concentration of atmospheric PM is associated with the development of lung cancer. The most simple and common way to protect an individual from airborne PM is to wear a face mask that filters out PM. In areas of high concentration PM, it is recommended to wear a face mask to minimize the exposure to PM. However, the use of N95 or KF94 masks can interfere with respiration in patients with chronic respiratory diseases who exhibit low pulmonary function, leading to an increased risk of respiratory failure. Conclusionally, reduction of the total amount of PM is considered to be important factor and strengthening the national warning notification system to vulnerable patients and proper early management of exacerbated patients will be needed in the future.

• Biomolecules & Therapeutics
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• v.4 no.2
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• pp.154-161
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• 1996

General pharmacological properties of LB-00014, an erythropoietin which was produced by recombinant DNA technique in Biotech Research Institute, LG Chemical Ltd. were examined. The administration of LB-00014 (60, 600, 6000 IU/kg, iv) in mice had no effect in general behavior and central nervous system, and no influences on normal body temperature, writhing syndromes induced by 0.7% acetic acid solution and chemoshock produced by strychnine and pentetrazole solution. LB-00014 (60, 600, 6000 IU/kg, iv) given to anesthetized rabbits showed no effect on blood pressure of carotid artery and respiration rates, and it did not influence the responses produced by injection of acetylcholine or epinephme. The administration of LB-00014 (601, 600, 6000 IU/kg, iv) in rats had no effect on the plasma prothrombin time, activated partial thromboplastin time and hemolytic action. The platelet aggregation induced by collagen in human plasma was not influenced by LB-00014 (10, 100, 1000 lU/kg, iv). It showed no direct effect at 100 and 1000IU/m1 in isolated stomach fundus and uterus of rats and ileum of guinea-pig, and it also had no inhibition of contraction produced by acetylcholine, oxytocin, serotonin and histamine in the above-mentioned preparations. It did not influence gastric secretion, pH and acid output at 6000 IU/kg, iv in rats, but showed a significant increase in intestinal propulsion of mice at 6000 IU/kg, iv. Its administration (60, 600, 6000 lU/kg, iv) caused no effect on urine and electrolyte excretion in rats. These results indicate that LB-00014 does not exsert any of serious pharmacological effects.

• Biomolecules & Therapeutics
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• v.4 no.2
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• pp.174-183
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• 1996

The general pharmacological properties of Artemisia extract powder (DA-9601) produced from Artemisia asiatica leaves were investigated in mice, rats, guinea pigs and rabbits. DA-9601 at the dose of 800 mg/kg po had no influences on general behaviour, barbital sleeping time and motor coordination of mice. The material at the oral dose of 800 mg/kg did exhibit neither analgesic action nor hypothermic effect. Anticonvulsant action, muscle relaxant action and the effect on intestinal propulsion were not identified at 800 mg/kg po. In the isolated ileum and trachea of guinea pig, the material did not show direct erect and inhibitory action of chemically or electrically stimulated contraction at the concentration of $2\times10^{-5}$g/ml. The sinus rates of atria and contractility of papillary muscle of guinea pig were not influenced by DA-9601 at a dose of $2\times10^{-5}$g/ml. No influences on blood pressure and respiration were observed at 40 mg/kg iv, in rabbits. However, transient decreases in blood pressure of rabbits were observed as given 120 mg/kg in iv route with slight respiratory depression, and slight diuretic effect could be found without any changes in $Na^+$ and $K^+$ excretion.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.529-533
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• 2006

To produce fresh-cut fruit products of high quality, the combined effects of postharvest calcium and heat treatment on Tsugaru apple were examined. Whole fruits were treated for 20 min at three different conditions: dipping in 3% $CaCl_2$ solution at $45^{\circ}C$ or ambient temperature, or in heated water at $45^{\circ}C$. The calcium content of the apples dipped in $CaCl_2$ solution at $45^{\circ}C$ was higher than that of the control and the non-heated calcium dipping. The fruits with calcium and heat treatment showed the same pattern of respiration rates as the control did during storage. The browning degree of the apple slices increased to approximately 3% after one-day storage, but no significant difference was observed between the treated and untreated apples. The fruits with $CaCl_2$ solution dipping at $45^{\circ}C$ had higher firmness than those with calcium dipping or heat treatment alone.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.1
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• pp.39-46
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• 2022

This study compared the effects of cocopeat and perlite growth media on the storability and quality of sweet pepper fruit stored using modified atmosphere packages (MAP) and carton boxes. The fruits were stored at 8℃ for 35 and 30 days, respectively. Perlite-grown fruits had a significantly lower size at harvest due to the medium's inability to hold plenty of water during the growing stage. Contrary to what is expected for small fruits, the result shows box-stored perlite-grown fruits to have lower weight loss and a longer shelf life than cocopeat-grown fruits, while MAP fruits have indifference. Perlite fruits also had a higher quality in terms of dry matter, soluble solids, and vitamin C, while box-stored fruits had a better visual quality. As expected, respiration and ethylene production rates were high, and fruits had similar after-storage firmness values. Based on the findings, perlite-grown sweet pepper fruits may have a better quality and give preference in a box storage condition.