• Journal of Radiation Protection and Research
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• v.48 no.3
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• pp.153-161
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• 2023

Background: Fukushima Medical University (FMU) is located 57 km northwest of the Fukushima Daiichi Nuclear Power Plant. Our laboratory has been conducting environmental radiation measurements continuously before and after the nuclear accident. We aimed to report the observed behavior of radiation originating from the released radioactive materials due to the accident, predict future trends, and disseminate the results to the local residents. Materials and Methods: Measurements of the counting rate by a diameter of 76 mm and a length of 76 mm thallium-doped sodium iodide (NaI[Tl]) scintillation detector (S-1211-T; Teledyne Brown Engineering Environmental Services) in the central part of the laboratory, and the dose rate outward at the window by NaI(Tl) scintillation detector and digital processor (EMF211; EMF Japan Co. Ltd.) were conducted. Results and Discussion: Measurements by Teledyne S-1211-T showed that in the early stages, radiation from radioactive isotopes with short half-lives was dominant, while radiation from radioactive isotopes with longer half-lives became dominant as the measurement period became longer. Through nonlinear least squares regression, both short and long half-lives were successfully determined. It was also possible to predict how the radiation dose would decrease. The environmental radiation trends around FMU were measured by the EMF211. Both measurements were affected by rainfall and snow accumulation. Decontamination work on the FMU campus impacted measurements by the EMF211 especially. Conclusion: The results of two types of measurements, one at the center and the other at the window side of the laboratory, were presented. By applying a simplified model, radiation from radioactive isotopes with short and long half-lives was identified. Based on these results, future trends were predicted, and the information was used for public communication with the local residents.

• Journal of Mushroom
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• v.3 no.2
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• pp.79-84
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• 2005

The research for incubation period, mycelial density, day required for primordial formation after inoculation(below DPI), number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating 100, 200, 300, 400, 500(${\mu}g/50g$) of $Na_2SeO_3$ is following. Incubation periods of P. cornucopiae are 20~23 days per each low concentration treatment with $Na_2SeO_3$. Compared to the control which took 22 days of incubation period, it is reduced 1 or 2 days. Mycelial density of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $500{\mu}g/50g$ is very compact. DPI of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $400{\mu}g/50g$ was reduced 1 or 2days, but $500{\mu}g/50g$ was increased 1 day. Number of valid stipes of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $400{\mu}g/50g$ is between 19 and 20. It was increased 1 or 2, as compared to 18 of control, but $500{\mu}g/50g$ was reduced to 1. Individual weight of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $400{\mu}g/50g$ was between 129 and 138g/850cc. It was increased 4.9~12.2% as compared to 123g/850cc of the control but $500{\mu}g/50g$ was 122g/50g. Accumulation amount of organic selenium for P. cornucopiae treated with $Na_2SeO_3$ between 100 and $500{\mu}g/50g$ was $2.73{\sim}8.19{\mu}g/g/dry$. It was increased 55~164 times as the concentration increased when compared to $0.05{\mu}g/g/dry$ of the control. In conclusion, incubation period, mycelial density, DPI, number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating 100, ${\sim}400{\mu}g$ of $Na_2SeO_3$ was increased, but $500{\mu}g/50g$ was reduced. So more than $500{\mu}g/50g$ concentration treatments are required research.

• Journal of Mushroom
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• v.3 no.2
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• pp.85-89
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• 2005

The research for incubation period, mycelial density, day required for primordial formation after inoculation(below DPI), number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating 600, 700, 800, 900, 1000(${\mu}g/50g$) of $Na_2SeO_3$ is following. Incubation periods of P. cornucopiae are 25~30 days per each treatment with $Na_2SeO_3$. Compared to the control which took 22 days of incubation period, it is increased 3 or 8 days for the treatment of $600{\sim}1000{\mu}g/50g$. Mycelial density of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ is very similar with control. DPI of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was increased 3 or 8 days. Number of valid stipes of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was between 10 and 16. It was decreased 2 or 8 as compared to 18 of control. Individual weight of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was between 94 and 116g/850cc. It was decreased 5.7~23.5% as compared to 123g/850cc of the control. Accumulation amount of organic selenium for P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was $9.1{\sim}10.8{\mu}g/g/dry$. It was increased 182~216 times as the concentration increased when compared to $0.05{\mu}g/g/dry$ of the control. In conclusion, incubation period, mycelial density, DPI, number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating $600{\sim}1000{\mu}g/g$ of $Na_2SeO_3$ was decreased. So that the optimal treatment was less $400{\mu}g/g$ than $600{\sim}1000{\mu}g/g$.

• Applied Chemistry for Engineering
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• v.28 no.3
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• pp.306-312
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• 2017

Changes in the cell growth and lipid accumulation of marine microalga Dunaliella tertiolecta were investigated in response to the combination of different stress factors including the variation of iron supply as a primary stress factor and different options in light irradiation and $CO_2$ supply as a secondary stress factor. High or limited Fe conditions could act as a stress for lipid synthesis. As a secondary stress factor, non-$CO_2$ condition was good for lipid accumulation, but the overall cell growth was sacrificed significantly after a long-time cultivation. Dark condition as a secondary stress factor also favored lipid accumulation and the extent of cell density reduction at the early period in the dark was small compared to other stress conditions. The two-stage cultivation strategy was necessary to maximize lipid production because tendencies of the cell growth and lipid content were not identical under the chosen stress condition. The first stage was for preparing a high cell density under the normal growth-favoring condition and the second stage was the stress condition to induce lipid accumulation in a short time. The short-term (12 h) incubation under the 5X Fe (3.25 mg/L) and dark conditions resulted in the best lipid productivity of 1.44 g/L/d providing 2 g/L inoculum at the second stage.

• Journal of Periodontal and Implant Science
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• v.31 no.2
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• pp.401-420
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• 2001

A novel glucanhydrolase from a mutant of Lipomyces starkeyi(KSM 22)has been shown effective in hydrolysis of mutan, reduction of mutan formation by Streptococcus mutans and removal pre-formed sucrose-dependent adherent microbial film and Lipomyces starkeyi KSM 22 dextranase has been strongly bound to hydroxyapatitie. These in vitro properties of Lipomyces starkeyi KSM 22 dextranase are desirable for its application as a dental plaque control agent. This study was performed to determine oral hygiene benefits and safety of dextranase(Lipomyces starkeyi KSM 22 dextranase)-containing mouthwash in human experimental gingivitis. This 3-week clinical trial was placebo-controlled double-blind design evaluating 1U/ml dextranase mouthwash and 0.12% chlorhexidine mouthwash. A total 39 systemically healthy subjects, who had moderate levels of plaque and gingivitis were included. At baseline, 1, 2 and 3 weeks, subjects were scored for plaque(Silness and $L{\ddot{o}e$ plaque index and plaque severity index), gingivitis($L{\ddot{o}e$ and Silness gingival index), and at baseline and 3 weeks of experiment, subjects were scored for plaque(Turesky-Quingley-Hein's plaque index and plaque severity index), tooth stain(Area and severity index system by Lang et al). Additionally, oral mucosal examinations were performed and subjects questioned for adverse symptoms. Two weeks after pre-experiment examinations and a professional prophylaxis, the subjects provided with allocated mousewash and instructed to use 20-ml volumes for 30s twice dailywithout toothbrushing. All the groups showed significant increase in plaque accumulation since 1 week of experiment. During 3 weeks' period, the dextranase group showed the least increase in plaque accumulation of Silness and $L{\ddot{o}e$ plaque index, compared to the chlorhexidine and placebo groups, but chlorhexidine group showed the least increase inplaque accumulation of Turesky-Quingley-Hein's plaque index. As for gingival inflammation, all the groups showed significant increase during 3 weeks of experiment. The dextranase group also showed the least increase in gingival index score, compared to the chlorhexidine as well as the placebo groups. Whereas the tooth stain was increased significantly in the chlorhexidine group, compared to the baseline score and the placebo group since 3 weeks of mouthrinsing. It was significantly increased after 3 weeks in the dextranase group, still less severe than the chlorhexidine group. As for the oral side effect, the dextranase group showed less tongue accumulation, bad taste, compared to the chlorhexidine group. From these results, mouthrinsing with Lipomyces starkeyi KSM 22 dextranase was comparable to 0.12% chlorhexidine mouthwashin inhibition of plaque accumulation and gingival inflammation and local side effects were if anything less frequent and less intense than chlorhexidine, in human experimental gingivitis. All data had provided positive evidence for Lipomyces starkeyi KSM 22 dextranase as an antiplaque agent and suggested that further development of dextranase formulations for plaque control are warranted.

• Journal of Periodontal and Implant Science
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• v.31 no.2
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• pp.371-388
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• 2001

A novel glucanhydrolase(DXAMase) from a mutant of Lipomyces starkeyi(KSM 22) has been shown effective in hydrolysis of mutan, reduction of mutan formation by Streptococcus mutans and removal pre-formed sucrose-dependentadherent microbial film and DXAMase has been strongly bound to hydroxyapatitie. These in vitro properties of Lipomyces starkeyi DXAMase are desirable for its application as a dental plaque control agent. This study was performed to determine the adjunctive oral hygiene benefits and safety of dextranase(Lipomyces starkeyi KSM 22 DXAMase)-containing mouthwash when used alongside normal tooth-brushing. This 6-month clinical trial was placebo-controlled double-blind design evaluating 1U/ml dextranase mouthwash and 0.12% chlorhexidine mouthwash. A total 39 systemically healthy subjects, who had moderate levels of plaque and gingivitis were included. At baseline, 1, 3 and 6 months, subjects were scored for plaque accumulation(Turesky modification of Quingley-Hein's plaque index), gingivitis status($L\ddot{o}e$ and Silness gingival index), and tooth stain(Area and severity index system by Lang et al). Additionally, oral mucosal examinations were performed and subjects questioned for adverse symptoms. Two weeks after pre-experiment examinations and a professional prophylaxis, the subjects provided with allocated mousewash and instructed to use 20-ml volumes for 30s twice daily after toothbrushing. All the groups showed significant increase in plaque accumulation since 1 month of experiment. During 6 months' period, the Dextranase mouthwash group showed the least increase in plaque accumulation, compared to the Chlorhexidine mouthwash and placebo groups. As for gingival inflammation, all the groups showed significant increase during 6 months of experiment. The Experimental group(Dextranase mouthwash) also showed the least increase in gingival index score, compared to the Positive control(Chlorhexidine mouthwash)as well as the Negative control(placebo)groups. Whereas the tooth stain was increased significantly in the Positive control group, compared to the baseline score and the Negative controlgroup since 3 months of mouthrinsing. It was significantly increased after 6 months in the Experimental group, still less severe than the Positive control group. As for the oral side effect, the Experimental group showed less tongue accumulation, bad taste, compared to the Positive control group. From these results, mouthrinsing with Lipomyces starkeyi KSM 22 dextranase provided adjunctive benefits to toothbrushing, comparable to 0.12% chlorhexidine mouthwash in inhibition of plaque accumulation and gingival inflammation and local side effects were if anything less frequent and less intense than chlorhexidine, with long-term use of the mouthwash. All data had provided positive evidence for Lipomyces starkeyi KSM 22 dextranase as an antiplaque agent and suggested that further development of dextranase formulations for plaque control are warranted.

• Land and Housing Review
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• v.14 no.1
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• pp.83-97
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• 2023

The study aims to provide an academic basis for the preservation and restoration of abandoned paddy wetland and the enhancement of its carbon accumulation function. First, the temporal change of the wetlands was analysed, and a typological classification system for wetlands was attempted with the goal of carbon reduction. The types of wetland were classified based on three variables: hydrological environment, vegetation, and carbon accumulation, with a special attention on the function of carbon accumulation. The types of abandoned paddy wetlands were classified into 12 categories based on hydrologic variables- either high or low levels of water inflow potential-, vegetation variables with either dominance of aquatic plants or terrestrial plants, and three carbon accumulation variables including organic matter production, soil organic carbon accumulation, and decomposition. It was found that the development period of abandoned paddy analyzed with aerial photographs provided by the National Geographic Information Institute happened between 2010 and 2015. In the case of the wetland in Daejeon 1 (DJMN01) farming stopped by 1990 and it appeared to be a similar structure to natural wetlands after 2010 . Over the past 40 years the abandoned paddy wetland changed to a high proportion of forests and agricultural lands. As time went by, such forests and agricultural lands tended to decrease rapidly and the lands were covered by artificial grass and other types of forests.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.2
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• pp.185-191
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• 1997

This experiment was conducted to determine the effects of a low-protein diet supplemented with DL-methionine plus L-cystine (Met + Cys) on the growth performance and fat accumulation of female broiler chicks during the growing period (3-6 wks old). A low-protein diet (17% CP; 3,200 ME kcal/kg) was supplemented with Met + Cys (1.1 : 1.0) at levels 0.75, 0.94, 1.25, 1.31 or 1.50% of diet, respectively. Another diet with 21% CP and 3,200 ME kcal/kg served as the control group. All essential amino acids were adjusted to meet the National Research Council (1984) requirement for chicks. Feed and water were given ad libitum. Body weight of the chicks fed the low-CP diets supplemented with Met + Cys were heavier than those of the control birds. Feed conversion ratio and feed intakes were not significantly different between and among the treatment groups. Similary, abdominal fat content was not significantly different among the various treatments except that of the chicks fed the low CP diet with 1.25% Met + Cys which was higher than that of the control group. Fatty acid synthetase (FAS), acetyl-CoA carboxylase (ACC) activities and carcass protein content were not influenced by dietary treatments. Carcass fat content was lowest in chicks fed low CP diet with 0.75% Met + Cys and highest in the group that received 1.50% Met + Cys supplementation. Liver triglyceride increased as Met + Cys supplementation level increased. Various lipid fraction concentrations (cholesterol ester, free cholesterol, and phospholipid) in the serum went up as Met + Cys increased up to 1.25% after which it levelled off. Results of this experiment suggest that it is possible to reduce dietary protein level from 21% to 17% for growing broiler chicks by the supplementation of Met + Cys when other EAA were sufficient.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.291-298
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• 2011

Yam extracts (Dioscorea batatas) have been reported to possess a variety of functions. However, studies on its osteogenic properties are limited. In this study, we investigated the effect of ethanol and water extracts on osteoblast proliferation and bone matrix protein synthesis, type I collagen and alkaline phosphatase (ALP), using osteoblastic MC3T3-E1 cell model. MC3T3-E1 cells were cultured with yam ethanol and water extracts (0~30 mg/L) within 39 days of osteoblast differentiation period. Cell proliferation was measured by MTT assay. Bone matrix proteins were assessed by the accumulation of type I collagen and ALP activity by staining the cell layers for matrix staining. Also, the secreted (media) matrix protein concentration (type I collagen) and enzyme activity (ALP) were measured colorimetrically. Yam ethanol and water extracts stimulated cell proliferation within the range of 15~30 mg/L at 15 day treatment. The accumulation of type I collagen in the extracellular matrix, as well as secreted collagen in the media, increased with increasing doses of yam ethanol (3~15 mg/L) and water (3~30 mg/L) extracts. ALP activity was not affected by yam ethanol extracts. Our results demonstrated that yam extracts stimulated osteoblast proliferation and enhanced the accumulation of the collagenous bone matrix protein type I collagen in the extracellular matrix. These results suggest that yam extracts may be a potential activator for bone formation by increasing osteoblast proliferation and increasing bone matrix protein type I collagen. Before confirming the osteogenic action of yam, further studies for clarifying how and whereby yam extracts can stimulate this ostegenesis action are required.

• Journal of Plant Biotechnology
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• v.5 no.1
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• pp.1-6
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• 2003

The adventitious root of Panax ginseng C.A. Meyer is regarded as an efficient alternative to cell culture or hairy root culture for biomass production due to its fast growth and stable metabolite production. To determine optimal culture conditions for the bioreactor culture of ginseng roots, experiments have been conducted on physical and chemical factors such as bioreactor type, dissolved oxygen, gas supply, aeration, medium type, macro- and micro-elements, medium supplement during culture period, sucrose concentration, osmotic agents, medium pH and light. Elicitation is a key step to increase ginsenoside accumulation in the adventitious roots but biomass growth is severely inhibited by elicitor treatment. To obtain high ginsenoside content with avoiding biomass decrease, we applied two-stage bioreactor culture system. Ginseng adventitious roots were cultured for 40 days to maximize biomass increase followed by elicitation for 7 days to enhance ginsenoside accumulation. We also experimented on types and concentrations of jasmonate to determine optimal elicitation methods. In this paper, we discussed several factors affecting the root propagation and ginsenoside accumulation. Based on the results obtained from previous experiments we have established large-scale bioreactor system (1 ton-10 ton) for the efficient production of ginseng adventitious roots and bioactive compounds including ginsenoside. Still, experiments are on going in our laboratory to determine other bioactive compounds having effects on diet, high blood pressure, DPPH elimination and increasing memories.