• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.359-369
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• 2018

Harmful algal blooms (HABs) are a serious problem for public health and fisheries industries, thus there exists a need to investigate the possible ways for effective control of HABs. In the present study, we investigated the algicidal effects of a newly developed GreenTD against the HABs (Chattonella marina, Heterosigma akashiwo, Cochlodinium polykriokides, and Heterocapsa circularisquama) and non-HABs (Chaetoceros simplex, Skeletonema sp. and Tetraselmis sp.), which is focused on the different population density and concentration gradients of algicidal substances. The time series viability of target alga was assessed based on the activity of Chl. a photosynthetic efficiency in terms of $F_v/F_m$, and in vivo fluorescence (FSU). Effective control of Raphidophyta, C. marina and H. akashiwo was achieved at a GreenTD concentration of $0.5{\mu}gL^{-1}$ and $0.2{\mu}gL^{-1}$, respectively, and regrowth of both the species was not observed even after 14 days. The inhibitory ratio of the dinoflagellate, C. polykriokides was more than 80% at $0.2{\mu}gL^{-1}$ of GreenTD. H. circularisquama was constantly affected in the presence of $0.2{\mu}gL^{-1}$ of GreenTD in the high- and low-population density experimental groups. On the other hand, diatoms, C. simplex, and Skeletonema sp. were not significantly affected even in the presence of $0.2{\mu}gL^{-1}$ of GreenTD and exhibited re-growth activity with the passage of incubation time. In particular, green alga Tetraselmis sp. remained unaffected even in the presence of the highest concentration of GreenTD ($1.0{\mu}gL^{-1}$), implying that non-HABs were not greatly influenced by the algicidal substances. As a result, the algicidal activity of GreenTD on the harmful and nonharmful algae was as follows: raphidophyte>dinoflagellates>diatoms>green alga. Consequently, our results indicate that inoculation of GreenTD substances into natural blooms at a threshold concentration ($0.2{\mu}gL^{-1}$) can maximize the algicidal activity against HABs species. If we consider the dilution and diffusion rate in the field application, it is hypothesized that GreenTD will demonstrate economic efficiency, thus leading to effective control against the target HABs in the closed bay.

• Korean Journal of Ecology and Environment
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• v.54 no.4
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• pp.346-362
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• 2021

A sediment control dam is an artificial structure built to prolong sedimentation in the main dam by reducing the inflow of suspended solids. These dams can affect changes in dissolved organic matter (DOM) in the water body by changing the river flow regime. The main DOM component for Yeongju Dam sediment control of the Naeseongcheon River was analyzed through 3D excitation-emission matrix (EEM) and parallel factor (PARAFAC) analyses. As a result, four humic-like components (C1~C3, C5), and three proteins, tryptophan-like components (C2, C6~C7) were detected. Among DOM components, humic-like components (autochthonous: C1, allochthonous: C2~C3) were found to be dominant during the sampling period. The total amount of DOM components and the composition ratio of each component did not show a difference for each depth according to the amount of available light (100%, 12%, and 1%). Throughout the study period, the allochthonous organic matter was continuously decomposing and converting into autochthonous organic matter; the DOM indices (fluorescence index, humification index, and freshness index) indicated the dominance of autochthonous organic matter in the river. Considering the relative abundance of cyanobacteria and that the number of bacteria cells and rotifers increased as autochthonous organic matter increased, it was suggested that the algal bloom and consequent activation of the microbial food web was affected by the composition of DOM in the water body. Research on DOM characteristics is important not only for water quality management but also for understanding the cycling of matter through microbial food web activity.

• Tuberculosis and Respiratory Diseases
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• v.54 no.3
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• pp.311-319
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• 2003

Background : Previous studies have suggested that a B-type natriuretic peptide(BNP) test can provide important information on diagnosis, as well as predicting the severity and prognosis of heart failure. Myocardial dysfunction is often observed in critically ill noncardiac patients admitted to the Intensive Care Unit, and the prognosis of the myocardial dysfunction needs to be determined. This study evaluated the predictability of BNP on the prognosis of critically ill noncardiac patients. Methods : 32 ICU patients, who were hospitalized from June to October 2002 and in whom the BNP test was evaluated, were enrolled in this study. The exclusion criteria included the conditions that could increase the BNP levels irrespective of the severity, such as congestive heart failure, atrial fibrillation, ischemic heart disease, and renal insufficiencies. A triage B-Type Natriuretic Peptide test with a RIA-kit was used for the fluorescence immunoassay of BNP test. In addition, the acute physiology and the chronic health evaluation (APACHE) II score and mortality were recorded. Results : There were 16 males and 16 females enrolled in this study. The mean age was 59 years old. The mean BNP levels between the ICU patients and control were significantly different ($186.7{\pm}274.1$ pg/mL vs. $19.9{\pm}21.3$ pg/mL, p=0.033). Among the ICU patients, there were 14(44----) patients with BNP levels above 100 pg/mL. The APACHE II score was $16.5{\pm}7.6$. In addition, there were 11 mortalities reported. The correlation between the BNP and APACHE II score, between the BNP and mortality were significant (r=0.443, p=0.011 & r=0.530, p=0.002). The mean BNP levels between the dead and alive groups were significantly different ($384.1{\pm}401.7$ pg/mL vs. $83.2{\pm}55.8$ pg/mL p=0.033). However, the $PaO_2/FiO_2$ did not significantly correlate with the BNP level. Conclusion : This study evaluated the BNP level was elevated in critically ill, noncardiac patients. The BNP level could be a useful, noninvasive tool for predicting the prognosis of the critically ill, noncardiac patients.

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.500-509
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• 2014

To prevent freezing of the road by fallen snow, Calcium chloride($CaCl_2$) as a deicer is used to very often and it can be harmful to roadside trees. This study was conducted to investigate the effects of Calcium chloride($CaCl_2$) as a deicer on growth and physiological traits of Acer triflorum according to different concentration of $CaCl_2$. We measured growth, chlorophyll contents, gas exchangement characteristics, chlorophyll fluorescence and mineral nutrition concentration in plant and soil. The experimental group was composed of four treatments including 0mM(control), 9mM(0.5 %), 18mM(1.0 %), 54mM(3.0 %). Before germinating new shoot, the dissolution of $CaCl_2$ was irrigated twice interval of a week. At 30 days after treatment, all treatments decreased total cholorophyll content, photosynthetic rate, transpiration rate, stomatal conductance and photochemical efficiency($F_v/F_m$) with increasing concentration of $CaCl_2$ and especially, they significantly reduced in 3.0 % treatment. In contrast, chlorophyll a/b ratio increased with an increase of $CaCl_2$ concentration and water use efficiency increased in 1.0 % and 3.0 % treatments. At 50 days after treatment, all treatments were decreased in chl a, chl b, total chlorophyll content, carotenoid content, photosynthetic capacity, photochemical efficiency($F_v/F_m$) and quantum yield of photosystem II(${\Phi}_{PSII}$) compared with control and 3.0 % treatments were withered. $Ca^{2+}$ and $Cl^-$ were accumulated in leaves and soil, which inhibited water absorption and electron transport and it caused the reduction of height growth rate more than 50 %. Although there was a little difference according to time and $CaCl_2$ concentration, all treatments decreased in growth rate and physiological activity slowed down. As time passed, these results got worse. Therefore we need to take a measure earlier in order to minimize damage of trees.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.3
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• pp.245-253
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• 2011

Purpose: The aim of this in vitro study was to estimate surface characteristic after peptide coating and investigate biological response of human mesenchymal stem cell to anodized titanium discs coated with RGD peptide by physical adhesion and chemical fixation. Materials and methods: Fluorescence isothiocyanate (FITC) modified RGD-peptide was coated on the anodized titanium discs (diameter 12 mm, height 3 mm) using two methods. One was physical adhesion method and the other was chemical fixation method. Physical adhesion was performed by dip and dry procedure, chemical fixation was performed by covalent bond via silanization. In this study, human mesenchymal stem cell was used for experiments. The experiments consisted of surface characteristic evaluation after peptide coating, analysis about cell adhesion, proliferation, differentiation, and mineralization. Obtained data are statistically treated using Kruskal-Wallis test and Bonferroni test was performed as post hoc test (P=.05). Results: The evaluation of FE-SEM images revealed no diffenrence at micro-surfaces between each groups. Total coating dose was higher at physical adhesion experimental group than at chemical fixation experimental group. In cell adhesion and proliferation, RGD peptide coating did not show a statistical significance compared with control group (P>.05). In cell differentiation and mineralization, physical adhesion method displayed significantly increased levels compared with control group and chemical fixation method (P<.05). Conclusion: RGD peptide coating seems to enhance osseointegration by effects on the response of human mesenchymal stem cell. Especially physical adhesion method showed more effective than chemical fixation method on response of human mesenchymal stem cell.

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.123-133
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• 2011

The objective of this study was to find optimal nutrient condition of container seedling production of two tropical species for high seedling quality. This study was conducted to investigate photosynthesis, chlorophyll fluorescence, chlorophyll contents, and growth performances of container seedlings of Eucalyptus pellita and Acacia mangium growing under four different fertilization treatments (Con., $0.5\;g{\cdot}l^{-1}$, $1.0\;g{\cdot}l^{-1}$, and $2.0\;g{\cdot}l^{-1}$ fertilization). E. pellita showed outstanding photosynthetic capacity, photochemical efficiency, and chlorophyll contents at $1.0\;g{\cdot}l^{-1}$ fertilization. Meanwhile, E. pellita showed the highest photosynthetic capacity, photochemical efficiency, and chlorophyll contents at $2.0\;g{\cdot}l^{-1}$ fertilization, as fertilization rate were increased, those of A. mangium increased. Like physiological characteristics, Both E. pellita at $1.0\;g{\cdot}l^{-1}$ fertilization and A. mangium at $2.0\;g{\cdot}l^{-1}$ fertilization were higher root collar diameter, height, biomass, and seedling quality index than other treatments. These results showed that E. pellita at $1\;g{\cdot}l^{-1}$ fertilization and A. mangium at $2.0\;g{\cdot}l^{-1}$ fertilization is optimal nutrient condition, respectively. Moreover, fertilization rate controlling is very important for growth and seedling quality of container seedling.

• Korean Journal of Poultry Science
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• v.41 no.2
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• pp.115-125
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• 2014

With Single Comb White Leghorn (WL) and Korean Native Chicken (KNC) breeds, we compared the stress response with chicken breeds that were subjected to a high stocking density. Stress response was analyzed by the quantity of telomeric DNA, the rate of DNA damage and the expression levels of heat shock proteins (HSPs) and hydroxyl-3-methyl-glutaryl coenzyme A reductase (HMGCR) genes on tissues and blood. The telomere length and telomere shortening rates were analyzed by quantitative fluorescence in situ hybridization on the nuclei of lymphocytes and tissues. The DNA damage rate of lymphocytes was quantified by the comet assay. The expression levels of HSP70, HSP90-${\alpha}$, HSP90-${\beta}$ and HMGCR genes were measured by quantitative real-time polymerase chain reaction in lymphocytes. There was no significant difference between KNC and WL in body weight, weight gain, telomere shortening rate and DNA damage rate. However, the growth rate significantly decreased in chickens raised under high stocking density conditions, as compared to the control group. The telomere-shortening rate, DNA damage and HSPs expression of the lymphocytes were significantly higher in the high stocking density group than the control. The stress condition and breeds had a significant effect on the expressions of HSP70, HSP90-${\alpha}$ and HSP90-${\beta}$ in lymphocytes, except HMGCR. The stress response of WL was higher than that of KNC, as analyzed to the expression of HSP70 and HSP90-${\alpha}$. Therefore, we concluded that the chickens which were exposed to a high stocking density had increased the individual physiological stress response regardless of breeds, and White Leghorns are more susceptible to stress condition than Korean Native Chickens.

• Journal of Embryo Transfer
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• v.16 no.2
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• pp.79-89
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• 2001

Steroid hormones control the expression of many cellular regulators, and a role thor estrogen in mouse oocytes has been well documented. The preovulatory $E_2$increment is generally accepted as the endocrine process regulating induction of in vivo oocyte maturation To address whether the activity of the T-type $Ca^{2+}$ channel is altered by 17 beta-estradiol ( $E_2$), we examined the actions of $E_2$on the calcium channel of mouse oocytes and early embryos. Oocrtes were collected from the oviduct of mice treated with pregnant mare's serum gonadotropin (PMSG) and human choronic gonadotropin (hCG). Whole cell voltage clamp technique and confocal microscopy were used to examine that $E_2$increase intracellular $Ca^{2+}$ concentration ([C $a^{2+}$]$_{i}$ ) via voltage dependent $Ca^{2+}$ channel (VDC) and estrogen receptor (FSR), and $E_2$concentration by the use of radioimmunoassay (RIA) were examined in mouse. The results obtained were as follows: The peak of $Ca^{2+}$ current induced by $E_2$increased 122% to 1.50$\pm$0.03 nA from 1.23$\pm$0.21 nA (n=15) in the presence of 5 mM extracellular $Ca^{2+}$ concentration ([C $a^{2+}$]$_{o}$ ). The increased $Ca^{2+}$ current was temporally associated with $Ca^{2+}$ transients. The intracellular $Ca^{2+}$ level increased 207%~30 s following the addition of 1${\mu}{\textrm}{m}$ $E_2$(relative fluorescence intensity: 836.4$\pm$131.2 for control, n=10, 1736.4$\pm$192.0 in the presence of $E_2$, n=10). $E_2$increased amplitude of $Ca^{2+}$ current and [C $a^{2+}$]$_{i}$ . $E_2$-induced $Ca^{2+}$ current and $E_2$concentration in blood were showed difference on the stage of embryo. These results suggest that $E_2$modulate $Ca^{2+}$ channel to increase $Ca^{2+}$ influx.$Ca^{2+}$ influx.

• Korean Journal of Animal Reproduction
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• v.27 no.2
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• pp.153-161
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• 2003

This study has evaluated effect of the spermatozoa incubation on the glycosidase activity and fertilizing ability in vitro in the pig. To identify sperm glycosidases specific for sugar residues found in the zona pellucida of pig oocytes, the spermatozoa were treated experimentally and assayed for activities of $\alpha$-L-fucosidase, $\alpha$-D-mannosidase, $\beta$-D-galactosidase and N-acetyl-$\beta$-D-glucosaminidase ($\beta$-GlcNAc'ase). The glycosidases activity were higher in spermatozoa incubated for 2h than without incubation. The $\beta$-GlcNAc'ase activity was at least two-fold higher than other glycosidase regardless of spermatozoa incubation. In the same glycosidases, the activity had a tendency to increase as time of spermatozoa incubation was prolonged, but there were no differences in spermatozoa incubated during the various periods (4~24h). The percentages of spermatozoa that reached acrosome reaction were affected by glycosidases in the medium (P<0.05, for mannosidase), and were higher in spermatozoa with that than without incubation. On the other hand, the spermatozoa motility were decreased with incubation periods, but no effects by different glycosidases on the change of sperm motility during the various periods of incubation. In other experiment, the binding and penetration of pig spermatozoa were tested with oocytes matured in vitro in the presence of various glycosidase. The penetration rates were decreased with incubation of spermatozoa when oocytes were inseminated in medium with different glycosidases. These rates were higher in spermatozoa non-incubated than with incubation for 2h (P<0.05 for GlcNAc'ase; P<0.01 for control group). The sperm-zona binding rate in control group were higherthan in medium with glycosidases. In addition, the highest binding rate were obtained in medium with GlcNAc'ase. In all glycosidases, the sperm-zona binding rate in spermatozoa without incubation were higher than incubation for 2h. The significant differences were obtained in spermatozoa treated with $\alpha$-D-mannosidase (P<0.05). These results suggest that $\beta$-GlcNAc'ase is present mainly in the plasma membrane of pig spermatozoa. It was also shown that the glycosidase activity were increased in all glycosidases in spite of low sperm-zona binding rate and penetration rates by spermatozoa incubation.

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.67-76
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• 2022

This study aimed to determine the photosynthesis and growth characteristics of Peucedanum japonicum T. grown under aquaponics in a plant factory (AP) by comparing those grown under hydroponic cultivation system (HP). The AP system raised 30 fishes at a density of 10.6 kg·m^-3 in a 367.5 L tank, and at HP, nutrient solution was controlled with EC 1.3 dS·m^-1 and pH 6.5. The pH level ranged from 4.0 to 7.1 for the AP system and 4.0 to 7.4 for the HP system. The pH level in the AP began to decrease with an increase in nitrate nitrogen (NO₃-N) and lasted bellower than pH 5.5 for 15-67 DAT. It was found that ammonium nitrogen (NH₄-N) continued to increase even under low pH conditions. EC was maintained at 1.3 to 1.5 dS·m^-1 in both systems. The concentration of major mineral elements in the fish tank was higher than that of the hydroponics, except for K and Mg. There was no significant difference in the photosynthesis characteristics, but the PIABS parameters were 30.4% lower in the AP compared to the HP at the 34DAT and 12.0% lower at the 74DAT. There was no significant difference in the growth characteristics, but the petiole length was 56% longer in the leaf grown under the AP system. While there was no significant difference in the fresh and dry weights of leaf and root, the leaf area ratio was 36.43% higher in the AP system. All the integrated results suggest that aquaponics is a highly-sustainable farming to safely produce food by recycling agricultural by-products, and to produce Peucedanum japonicum as much as hydroponics under a proper fish density and pH level.