• Journal of Environmental Science International
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• v.21 no.5
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• pp.633-640
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• 2012

White light and compound light were found to be the ideal light sources for improving the functionality and ornamental value of indoor plants and reducing the cost of maintenance, but because compound light hinders people from recognizing the original color of plants and makes their eyes easily tired, white light was considered the optimal light satisfying all of the ornamental value, economic efficiency and functionality resulting from plant growth. On the other hand, in the results of examining physiological changes before and after treatment on fine dust PM10 and carbon dioxide removal capacity in a closed chamber under an artificial light source, the patterns of carbon dioxide and fine dust removal were similar among the treatment groups according to light condition, but according to plant type, the removal rate per unit leaf area was highest in $Spathiphyllum$ and lowest in $Dieffenbachia$. In the experiment on dust and carbon dioxide removal, the photosynthetic rate was over 2 times higher after the treatment, and the rate increased particularly markedly under compound light and white light, suggesting that the photosynthetic rate of plants increases differently according to light quality. These results show that light quality has a significant effect on the photosynthetic rate of plants, and suggests that plants with a high photosynthetic rate also have a high carbon dioxide and dust removal capacity. In conclusion, the photosynthetic rate of foliage plants increased under white and blue light that affect photosynthesis and the increased photosynthetic rate reduced carbon dioxide and fine dust, and therefore white and compound light were found to be the optimal light sources most functional and economically efficient in improving ornamental value and indoor air quality.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.11
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• pp.1585-1592
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• 2016

The present experiment was conducted to evaluate the effect of simulated heat stress on digestibility and methane ($CH_4$) emission. Four non-lactating crossbred cattle were exposed to $25^{\circ}C$, $30^{\circ}C$, $35^{\circ}C$, and $40^{\circ}C$ temperature with a relative humidity of 40% to 50% in a climatic chamber from 10:00 hours to 15:00 hours every day for 27 days. The physiological responses were recorded at 15:00 hours every day. The blood samples were collected at 15:00 hours on 1st, 6th, 11th, 16th, and 21st days and serum was collected for biochemical analysis. After 21 days, fecal and feed samples were collected continuously for six days for the estimation of digestibility. In the last 48 hours gas samples were collected continuously to estimate $CH_4$ emission. Heat stress in experimental animals at $35^{\circ}C$ and $40^{\circ}C$ was evident from an alteration (p<0.05) in rectal temperature, respiratory rate, pulse rate, water intake and serum thyroxin levels. The serum lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase activity and protein, urea, creatinine and triglyceride concentration changed (p<0.05), and body weight of the animals decreased (p<0.05) after temperature exposure at $40^{\circ}C$. The dry matter intake (DMI) was lower (p<0.05) at $40^{\circ}C$ exposure. The dry matter and neutral detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ compared to $25^{\circ}C$ and $30^{\circ}C$ exposure whereas, organic matter (OM) and acid detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ than $40^{\circ}C$ thermal exposure. The $CH_4$ emission/kg DMI and organic matter intake (OMI) declined (p<0.05) with increase in exposure temperature and reached its lowest levels at $40^{\circ}C$. It can be concluded from the present study that the digestibility and $CH_4$ emission were affected by intensity of heat stress. Further studies are necessary with respect to ruminal microbial changes to justify the variation in the digestibility and $CH_4$ emission during differential heat stress.

• Journal of Korean Society of Forest Science
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• v.84 no.3
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• pp.306-318
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• 1995

To investigate the effect of low light intensities and the inoculation of Frankia and/or Alpova diplophloeus on the symbioses development and their host growth, red alder(Alnus rubra Bong.) seedlings were grown in an air - filtered walk - in growth chamber with either $N_2$ - fixing Frankia inoculation or N - fertilization and live or dead spore inoculation of the ectomycorrhizal fungus A. diplophloeus(Zeller & Dodge) Trappe & Smith. When they were 20 weeks old, the seedlings were grown under three levels of light intensities of 680, 320 and $220{\mu}mol/m^2/s$ PPFD(photosynthetic photon flux density) for three weeks. PPFD of 220 significantly decreased the development of A. diplophloeus mycorrhizae and nodules, the rates of $N_2$ - fixation and $CO_2$ exchange, and the growth of tile seedlings. PPFD 320 significantly decreased the $CO_2$ exchange rate only. Frankia inoculation significantly increased mycorrhiza formation and seedling growth. Alpova inoculation significantly increased seedling growth but not nodule development and $N_2$ - fixation. None of the symbionts affected $CO_2$ exchange rates. Frankia was more critical for seedling growth and mycorrhizal development than the mycorrhizal fungus for seedling growth and nodule development.

• Economic and Environmental Geology
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• v.36 no.5
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• pp.349-356
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• 2003

As industrial activities are growing, pollutants found in the contaminated land are getting diverse. Some contaminated areas are subject to mixed wastes containing both organic and inorganic wastes such as hydrocarbon and heavy metals. This study concerns with the influence of the degradation of organic pollutants on the coexisting heavy metals, expecially for As. As mainly exists as two different oxidation state; As(III) and As(V) and the conversion between the two chemical forms may be induced by organic degradation in the soil contaminated by mixed wastes. We operated microcosm in an anaerobic chamber for 60 days, using sandy loam. The soils in the microcosm are artificially contaminated both by tetradecane and As, with different combination of As(III) and As(V); As(III):As(V) 1:1, As(III) only and As(V) only. Although not systematic, ratio of As(III)/As(Total) increase slightly at the later stage of experiment. Considering complicated geochemical reactions involving oxidation/reduction of organic materials, Mn/Fe oxides and As, the findings in the study seem to indicate the degradation of the organics is connected with the As speciation. That is to say, the As(V) can be reduced to As(III) either by direct or indirect influence induced by the organic degradation. Although Fe and Mn are good oxidising agent for the oxidation of As(III) to As(V), organic degradation may have suppressed reductive dissolution of the Fe and Mn oxides, causing the organic pollutants to retard the oxidation of As(III) to As(V) until the organic degradation ceases. The possible influence of organic degradation on the As speciation implies that the As in mixed wastes may be have elevated toxicity and mobility by partial conversion from As(V) to As(III).

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.4
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• pp.329-338
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• 2020

Rhinorrhea in allergic rhinitis (AR) is characterized by the secretion of electrolytes in the nasal discharge. The secretion of Cl^- and HCO₃^- is mainly regulated by cystic fibrosis transmembrane conductance regulator (CFTR) or via the calcium-activated Cl^- channel anoctamin-1 (ANO1) in nasal gland serous cells. Interleukin-4 (IL-4), which is crucial in the development of allergic inflammation, increases the expression and activity of ANO1 by stimulating histamine receptors. In this study, we investigated ANO1 as a potential therapeutic target for rhinorrhea in AR using an ANO1 inhibitor derived from a natural herb. Ethanolic extracts (30%) of Spirodela polyrhiza (SP_EtOH) and its five major flavonoids constituents were prepared. To elucidate whether the activity of human ANO1 (hANO1) was modulated by SP_EtOH and its chemical constituents, a patch clamp experiment was performed in hANO1-HEK293T cells. Luteolin, one of the major chemical constituents in SP_EtOH, significantly inhibited hANO1 activity in hANO1-HEK293T cells. Further, SP_EtOH and luteolin specifically inhibited the calcium-activated chloride current, but not CFTR current in human airway epithelial Calu-3 cells. Calu-3 cells were cultured to confluency on transwell inserts in the presence of IL-4 to measure the electrolyte transport by Ussing chamber. Luteolin also significantly inhibited the ATP-induced increase in electrolyte transport, which was increased in IL-4 sensitized Calu-3 cells. Our findings indicate that SP_EtOH and luteolin may be suitable candidates for the prevention and treatment of allergic rhinitis. SP_EtOH^- and luteolin-mediated ANO1 regulation provides a basis for the development of novel approaches for the treatment of allergic rhinitis-induced rhinorrhea.

• Research in Plant Disease
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• v.19 no.1
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• pp.55-59
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• 2013

The purpose of this experiment was to investigate the development of new spot disease on the leaf and stem of rosemary (Rosmarinus officinalis) in commercial greenhouses at Jeonju and Namwon in Korea. Incidence of target spot on rosemary was higher at the end of the rainy season with high humidity. Those symptoms were black ring spots (3-5 mm in diameter) and withering on green leaves and stems. Conidiophores and conidia were formed on the infected tissue in moist chamber and conidia were shown as the cylindrical and oval types in chain, ranged from 55 to $275{\mu}m$ in length, and 7 to $14{\mu}m$ in width. Conidia with eight to ten pseudosepta were formed on the conidiapore. The optimum growth temperature of isolates was $30^{\circ}C$ on the PDA medium under the dark condition. In the pathogenesis test, the target spot and withering symptoms were appeared on the leaves and stems 3 days after inoculation showing similar symptoms compared to those of in nature. The same fungus was re-isolated from infected lesion, indicating that Corynespora cassiicola caused leaf target spot and twig blight on rosemary. The rDNA ITS nucleotide sequences of the pure cultured isolate from the diseased area on rosemary showed 100% similarity to the sequences of C. cassiicola available in the GenBank database (JQ595296, JQ595297, FJ852715 and AY238606). Therefore, we report that the target spot of leaves and stems in rosemary was caused by C. cassiicola.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.48-53
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• 1995

This study investigates a simple mathematical model for the quantitative estimation of regional myocardial blood flow in experimental canine coronary artery thrombosis using Rb-82 dynamic myocardial positron emission tomography. The coronary thrombosis was induced using the new catheter technique by narrowing the lumen of coronary vessel gradually, which finally led to partial obstruction of coronary artery. Ten Rb-82 dynamic myocardial PET scans were performed sequentially for each experiment using our 5, 10 and 20 second acquisition protocol, respectively, and three regions of interest were drawn on the transaxial slices, one on left ventricular chamber for input function and the other two on normal and decreased perfusion segments for the flow estimation in those regions. Single compartment model has been applied to the measured sets of regional PET data, and the rate constants of influx to myocardial tissue were calculated for regional myocardial flow estimates with the three parameter fits of raw data by the Levenberg-Marquardt method. The results showed that, (1) single compartment model suggested by Kety-Schmidt could be used for the simple estimation of regional myocardial blood flow, (2) the calculated regional myocardial blood flow estimates were dependent on the selection of input function, which reflected partial volume effect and left ventricular wall motion, and (3) mathematically fitted input and tissue time activity curves were more suitable than the direct application of the measured data in terms of convergence.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.255-263
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• 2011

Projected increases in atmospheric $CO_2$ concentration ([$CO_2$]) and temperature ($T_a$) have the potential to alter in rice growth and yield. However, little is known about whether $T_a$ warming with elevated [$CO_2$] modify plant architecture. To better understand the vertical profiles of leaf area index (LAI) and the flag leaf morphology of rice grown under elevated $T_a$ and [$CO_2$], we conducted a temperature gradient field chamber (TGC) experiment at Gwangju, Korea. Rice (Oryza sativa L. cv. Dongjin1ho) was grown at two [$CO_2$] [386 (ambient) vs 592 ppmV (elevated)] and three $T_a$ regimes [26.8 ($\approx$ambient), 28.1 and $29.8^{\circ}C$] in six independent field TGCs. While elevated $T_a$ did not alter total LAI, elevated [$CO_2$] tended to reduce (c. 6.6%) the LAI. At a given canopy layer, the LAI was affected neither by elevated [$CO_2$] nor by elevated $T_a$, allocating the largest LAI in the middle part of the canopy. However, the fraction of LAI distributed in a higher and in a lower layer was strongly affected by elevated $T_a$; on average, the LAI distributed in the 75-90 cm (and 45-60 cm) layer of total LAI was 9.4% (and 35.0%), 18.8% (25.9%) and 18.6% (29.2%) in ambient $T_a$, $1.3^{\circ}C$ and $3.0^{\circ}C$ above ambient $T_a$, respectively. Most of the parameters related to flag leaf morphology was negated with elevated [$CO_2$]; there were about 12%, 5%, 7.5%, 15% and 21% decreases in length (L), width (W), L:W ratio, area and mass of the flag leaf, respectively, at elevated [$CO_2$]. However, the negative effect of elevated [$CO_2$] was offset to some extent by $T_a$ warming. All modifications observed were directly or indirectly associated with either stimulated leaf expansion or crop phenology under $T_a$ warming with elevated [$CO_2$]. We conclude that plant architecture and flag leaf morphology of rice can be modified both by $T_a$ warming and elevated [$CO_2$] via altering crop phenology and the extent of leaf expansion.

• Korean Journal of Environmental Agriculture
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• v.36 no.2
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• pp.73-79
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• 2017

BACKGROUND: Carbonized biomass is a carbon-rich solid product obtained by the pyrolysis of biomass. It has been suggested to mitigate climate change through increased carbon storage and reduction of greenhouse gas emission. The objective of this study was to evaluate carbon dioxide ($CO_2$) and nitrous oxide ($N_2O$) emissions from soil after carbonized biomass addition. METHODS AND RESULTS: The carbonized biomass was made from a pyrolyzer, which a reactor was operated about $400{\sim}500^{\circ}C$ for 5 hours. The treatments were consisted of a control without input of carbonized biomass and two levels of carbonized biomass inputs as 6.06 Mg/ha for CB-1 and 12.12 Mg/ha for CB-2. Emissions of $CO_2$ and $N_2O$ from orchard soil were determined using closed chamber for 13 weeks at $25^{\circ}C$ of incubation temperature. It was shown that the cumulative $CO_2$ were $209.4g\;CO_2/m^2$ for CB-1, $206.4g\;CO_2/m^2$ for CB-2 and $214.5g\;CO_2/m^2$ for the control after experimental periods. The cumulative $CO_2$ emission was similar in carbonized biomass input treatment compared to the control. It was appeared that cumulative $N_2O$ emissions were $4,478mg\;N_2O/m^2$ for control, $3,227mg\;N_2O/m^2$ for CB-1 and$ 2,324mg\;N_2O/m^2$ for CB-2 at the end of experiment. Cumulative $N_2O$ emission contents significantly decreased with increasing the carbonized biomass input. CONCLUSION: Consequently the carbonized biomass from byproducts such as pear branch residue could suppress the soil $N_2O$ emission. The results fromthe study imply that carbonized biomass can be utilized to reduce greenhouse gas emission from the orchard field.

• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.107-113
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• 2003

This study was carried out to improve the performance of pre-developed heat recovery devices attached to exhaust-gas flue connected to combustion chamber of greenhouse heating system. Four different units were compared in the aspect of heat recovery performance; A-, B-, and C-types are exactly the same with the old ones reported in previous studies. D-type newly developed in this experiment is mainly different with the old ones in its heat exchange area and tube thickness. But airflow direction(U-turn) and pipe arrangement are similar with previous three types. The results are summarized as follows; 1. System performances in the aspect of heat recovery efficiency were estimated as 42.2% for A-type, 40.6% for B-type, 54.4% for C-type, and 69.2% for D-type. 2. There was not significant improvement of heat recovering efficiency between two different airflow directions inside the heat exchange system. But considering current technical conditions, straight air flow pattern has more advantage than hair-pin How pattern (U-turn f1ow). 3. The main factors influencing on heat recovery efficiency were presumably verified to be the total area of heat exchange surface, the thickness of ail-flow pipes, and the convective heat transfer coefficient influenced by airflow velocity under the conditions of allowable pipe durability and safety. 4. Desirable blower capacity for each type of heat recovery units were significantly different to each other. Therefore, the optimum airflow capacity should be determined by considering in economic aspect of electricity required together with the optimum heat recovery performance of given heat recovery systems.