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High-Temperature Cesium (Cs) Retention Ability of Cs-Exchanged Birnessite (세슘(Cs)으로 이온 교환된 버네사이트의 고온에서의 Cs 고정 능력)

  • Yeongkyoo Kim
    • Korean Journal of Mineralogy and Petrology
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    • v.36 no.4
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    • pp.313-321
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    • 2023
  • Numerous studies have investigated the adsorptive sequestration of radioactive cesium in the natural environment. Among these studies, adsorption onto minerals and high-temperature treatment stand out as highly effective, as demonstrated by the use of zeolite. In this study, cesium was ion-exchanged with birnessite and subsequently underwent high-temperature treatment up to 1100℃ to investigate both mineral phase transformation and the leaching characteristics of cesium. Birnessite has a layered structure consisting of MnO6 octahedrons that share edges, demonstrating excellent cation adsorption capacity. The high-temperature treatment of cesium-ion-exchanged birnessite resulted in changes in the mineral phase, progressing from cryptomelane, bixbyite, birnessite to hausmannite as the temperature increased. This differs from the phase transformation observed in the tunneled manganese oxide mineral todorokite ion-exchanged with cesium, which shows phase transformation only to birnessite and hausmannite. The leaching of cesium from cesium-ion-exchanged birnessite was estimated by varying the reaction time using both distilled water and a 1 M NaCl solution. The leaching quantity changed according to the treatment temperature, reaction time, and type of reaction solution. Specifically, the cesium leaching was higher in the sample reacted with 1 M NaCl compared to the sample with distilled water and also increased with longer reaction time. For the samples reacted with distilled water, the cesium leaching initially increased and then decreased, while in the NaCl solution, the leaching decreased, increased again, and finally nearly stopped like the sample in the distilled water for the sample treated at 1100℃. These changes in leaching are closely associated with the mineral phases formed at different temperatures. The phase transformation to cryptomelane and birnessite enhanced cesium leaching, whereas bixbyite and hausmannite hindered leaching. Notably, hausmannite, the most stable phase occurring at the highest temperature, demonstrated the greatest ability to inhibit cesium leaching. This results strongly suggest that high-temperature treatment of cesium-ion-exchanged birnessite effectively immobilizes and sequesters cesium.

Assessment of Hot Water Treatment and Lime Sulfur Mixture on Germination and Disinfection Efficacy of Organic Wheat Seeds (온탕침지법과 석회유황합제 처리가 유기농 밀 종자의 발아와 소독효과 미치는 영향 평가)

  • Min-Jeong Kim;One-Sung Park;Chang-Ki Shim;Jae-Hyeong Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.68 no.4
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    • pp.371-382
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    • 2023
  • This study aimed to estimate optimal treatment for enhancing the germination rate and disinfections effect of organic wheat varieties, Jokyung, Geumgang, Saegumgang, and Baekgang using hot water treatment and lime sulfur mixture. Before disinfection, the germination rates of the seeds averaged 86.3±2.5% to 87.5±2.9%, while the infection levels caused by fungi and bacteria were observed to be 22.5±2.9% to 38.3±2.5% and 18.8±4.8% to 23.8±2.5%, respectively. The germination rates of four wheat varieties under hot water treatments were either the same or higher compared to untreated seeds. As the temperature and treatment time of hot water treatment increased, the contamination levels of fungi and bacteria decreased. The optimal hot water treatment for the seeds was observed at 55℃ for 10 minutes, resulting in germination rates averaging 90.0±0.0% to 97.5±2.9%, which were either the same or higher than untreated seeds. The disinfection effectiveness against fungi and bacteria was high, averaging 83.3~93.5% and 100%, respectively. Additionally, an investigation was conducted on the germination rates and microbial disinfection efficacy of 0.2% and 0.4% lime-sulfur mixture with varying treatment times, 3 to10 minutes for each wheat variety. As the treatment time elapsed, no significant differences in germination rates were observed among four wheat varieties. However, the germination rates were higher compared to the untreated group (86.3~87.5%), and the optimal treatment time was found to be 7 minutes or 10 minutes, resulting in an average reduction of 90.0~96.0% in contamination levels of fungi and bacteria. Therefore, the germination rates and disinfection effects varied depending on the treatment conditions of hot water treatment and lime-sulfur mixture applied for the disinfection of the four varieties of organic wheat seeds. However, it is considered that treating the seeds with hot water treatment at 55℃ for 10 minutes or with 0.2% or 0.4% lime-sulfur compound for 10 minutes enhances germination rates and reduces the contamination rate of fungi and bacteria compared to untreated seeds. Thus, these environmentally friendly seed disinfection technologies are likely to be highly useful in agricultural fields.

The studies on wrinkle recovery improvement for silk fabrics (견직물의 방추성 개선연구)

  • 김병호;정진영
    • Journal of Sericultural and Entomological Science
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    • no.11
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    • pp.23-29
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    • 1970
  • This experiment is to improve the wrinkle recovery (W.R.) of silk fabrics. The silk fabrics is creased very well, and the crease is the serious defection of it. This experiment is to improve the nature by use of formaldehyde on fabrics. The reagents used were HCl, CH$_3$COOH, CaC$_2$, HCHO, Na$_2$CO$_3$, NH$_4$OH, NaOH and NaHCO$_3$. The silk fabrics was treated, to compare 1 he influence of conditions, by varying the quantities of reagents and the temperature of solution, and the reaction time. The cotton fabrics and the viscose rayon were sunk with the silk at the same condition to be compared the influence. 1) Those of the most suitable temperature to improve for the better W.R. are 75$^{\circ}C$ for silk, 35-45$^{\circ}C$ for cotton, and no particular temperature under 75$^{\circ}C$ for viscose rayon. 2) The W.R. improvements after treated at the temperature of 1) were 11% for silk and 33.4% for cotton. 3) There are the best treating time for every fabrics. They were 60 to 90 min. for viscose rayon when HAC Ras used for solvent. It took, however, 60min. of the best time for silk, 120 min. for cotton, and 40 min. for viscose rayon when acetic anhydride instead of HAC was used. 4) It was possible to improve 16.6% of W.R. for silk at the most suitable treating time, 25.0% for cotton, and 13.3% for viscose rayon. 5) Acetic anhydride was rather more effective to improve W.R. of both silk and viscose rayon than HAC. 6) Treating time was also shorter in case of using acetic anhydride than HAC. 7) The improvement of W.R. were 8.3% for silk at the 10 to 14 ml. of HCHO the best volume, 21. 5% for cotton at 18m!. of HCHO, and 70% of for viscose rayon at 14 to 18ml. of HCHO. 8) The most effective quantity of HCI is 14 ml. for both silk and cotton. The W.R. improvement of silk was 22.2%, and that of cotton 19.5%. 9) The W.R. of 83.3% the best for silk and 61. 6% for cotton were gained when 4.2gr. of NaHCO$_3$ brings down the percent of W.R. for both silk and cotton. 10) The more NaOH and NH$_4$OH as neutralizing agents, the less effectivity of W.R. until the quantities of the reagents are reached to a special range which are 3. 3m!. for silk and 3.3-6.6 ml. for cotton, and then we can see the W.R. increasing as the quantities of reagents are increased. These facts were evident in case of silk and cotton. We can also see with this fact that the reminder of 〔OH$\^$-/〕 neutralizing 〔CH$\^$+/〕in solution makes it possible to treat formaldehyde on fabrics. 11) Low curing temperature was comparatively better for silk, and high temperature better for cotton. 12) The result of this experiment shows that the Improvement of W.R. for silk was possible to 94% which means 22% W.R. increase compared to the untreated silk. This effect also shows that the improvement to W '||'&'||' W (wash and wear) of silk will be possible.

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Culture Conditions of Aspergillus oryzae in Dried Food-Waste and the Effects of Feeding the AO Ferments on Nutrients Availability in Chickens (건조한 남은 음식물을 이용한 Aspergillus oryzae균주 배양조건과 그 배양물 급여가 닭의 영양소 이용률에 미치는 영향)

  • Hwangbo J.;Hong E. C.;Lee B. S.;Bae H. D.;Kim W.;Nho W. G.;Kim J. H.;Kim I. H.
    • Korean Journal of Poultry Science
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    • v.32 no.4
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    • pp.291-300
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    • 2005
  • Two experiments were carried out to assess the appropriate incubation conditions namely; duration, moisture content and the ideal microbial inoculant for fermented dried food waste(EW) offered to broilers. The nutrient utilization of birds fed the FW diets at varying dietary inclusion rates was also compared with a control diet. In Experiment 1, different moisture contents(MC) of 30, 40, 50 and $60\%$ respectively were predetermined to establish the ideal duration of incubation and the microbial inoculant. A 1mL Aspergillus oryzae(AO) $(1.33\times10^5\;CFU/mL)$ was used as the seed inoculant in FW. This results indicated that the ideal MC for incubation was $40\~50\%$ while the normal incubation time was > 72 hours. Consequently, AO seeds at 0.25, 0.50, 0.75 and 1.00mL were inoculated in FW to determine its effect on AO count. The comparative AO count of FW incubated for 12 and 96 hours, respectively showed no significant differences among varying inoculant dosage rates. The FW inoculated with lower AO seeds at 0.10, 0.05 and 0.01mL were likewise incubated for 72 and 96 hours, respectively and no changes in AO count was detected(p<0.05). The above findings indicated that the incubation requirements for FW should be $%40\~50\%$ for 72 hours with an AO seed incoulant dosage rate of 0.10mL. Consequently, in Experiment II, after determining the appropriate processing condition for the FW, 20 five-week old male Hubbard strain were used in a digestibility experiment. The birds were divided into 4 groups with 5 pens(1 bird per pen). The dietary treatments were; Treatment 1 : Control(Basal diet), Treatment 2 : $60\%$ Basal+4$40\%$ FW, Treatment 3 : $60\%$ $Basal+20\%\;FW+20\%$ AFW(Aspergillus oryzae inoculate dried food-waste diet) and Treatment 4: $60\%$ Basal+$40\%$ Am. Digestibility of treatment 2 was lowed on common nutrients and amino acids compared with control(p<0.05) and on crude fat and phosphorus compared with AFW treatments(T3, T4)(plt;0.05). Digestibility of treatment 3 and 4 increased on crude fiber and crude ash compared treatment 2 (p<0.05). Digestibility of control was high on agrinine, leucine, and phenylalnine of essential amino acids compared with treatment 3 and 4(p<0.05), and diestibility of treatment 3 and 4 was improved on arginine, lysine, and threonine of essential amino acids. Finally, despite comparable nutrient utilization among treatments, birds fed the dietary treatment containing AO tended to superior nutrient digestion to those fed the $60\%$ Basa1+$40\%$ FW.

Compilation of 104 Experimental Theses on the Antitumor and Immuno-activating therapies of Oriental Medicine (한의학의 항종양 면역치료에 관한 연구 -1990년 이후 발표된 실험논문을 중심으로-)

  • Kang Yeon Yee;Kim Tai Im;Park Jong Ho;Kim Sung Hoon;Park Jong Dai;Kim Dong Hee
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.1
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    • pp.1-24
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    • 2003
  • This study was done to compile 104 experimental theses which are related to the antitumor and immuno-activating therapies between February 1990 through February 2002. Master's and doctoral theses were dassified by schools, degrees, materials, effects, experimental methods of antitumor and immunoactivity, and results. The following results were obtained from this study : 1. Classifying the theses by the school, 34.6% were presented by Daejeon University, 29.8% by Kyung-hee University and 11.5% by Won-kwang University. Of all theses, 51.0% were aimed for the doctoral degree and 43.3% were for the master's degree. All of three universities have their own cancer centers. 2. Classifying the theses by herb materials, complex prescription accounted for 60.3%, single herb accounted for 24.8% and herbal acupuncture accounted for 14.2%. Considering the key principles of the traditional medicine, complex prescription was much more thoroughly studied than single herb prescription. The results showed that the complex prescription had both antitumor activity and immuno-activating activity, which might reflects on multi-activation mechanisms by complex components. 3. Classifying the theses by the efficacy of herbs examined, in single herb, invigorating spleen and supplementing was 35.5%, expelling toxin and cooling was 29.0%, activating blood flow and removing blood stasis was 12.9%. In herbal acupuncture, invigorating spleen and supplementing was 52.9%, expelling toxin and cooling was 29.4%. In complex prescription, pathogen-free status was 41.9%, strengthening healthy qi to eliminate pathogen was 35.5%, strengthening healthy qi was 22.6%. It is presumed that the antitumor and immunoactivating therapy based on syndrome differentiation is the best way to develop oriental oncology. 4. Classifying the theses by antitumor experiments, cytotoxic effect was 48.1 %, survival time was 48.1 % and change of tumor size was 42.3%. Survival rate was not necessarily correlated with cytotoxicity. These data reflect the characteristic, wholistic nature of the oriental medicine which is based on BRM (biological response modifier). 5. Classifying the theses by immunoactivating experiments, hemolysin titer was 51.0%, hemagglutinin titer was 46.2% and NK cell's activity was 44.2%. In the future studies, an effort to elucidate specific molecular and cellular mechanisms of cytokine production in the body would be crucial. 6. Classifying the theses according to the data in terms of antitumor activity, 50% was evaluated good, 24.0% was excellent, and 15.5% have no effect. In an evaluation of immuno-activating activity, 35.9% was excellent and 18.0% showed a little effect. The index point, as described here, may helps to use experimental data for clinical trials. Changes in index points by varying dosage implicate the importance of oriental medical theory for prescription. 7. In 167 materials, IIP (immunoactivating index point, mean : 3.12±0.07) was significantly higher than AIP(antitumor index point, mean : 2.83±0.07). These data demonstrate that the effect of herb medicine on tumor activity depends more on immunoactivating activity than antitumor activity. This further implies that the development of herbal antitumor drugs must be preceded by the mechanistic understanding of immunoactivating effect. 8. After medline-searching tumor and herb-related articles from NCBI web site, we conclude that most of the studies are primarily focused on biomolecular mechanisms and/or pathways. Henceforth, we need to define the biomolecular mechanisms and/or pathways affected by herbs or complicated prescriptions. 9. Therefore, the most important point of oriental medical oncology is to conned between experimental results and clinical trials. For the public application of herbal therapy to cancer, it is critical to present the data to mass media. 10. To develop the relationship of experimental results and clinical trials, university's cancer clinic must have a long-range plan related to the university laboratories and, at the same time, a regular consortium for this relationship is imperative. 11. After all these efforts, a new type herbal medicine for cancer therapy which is to take care of the long-term administering and safety problem must be developed. Then, it would be expected that anti-tumor herbal acupuncture can improve clinical symptoms and quality of life (QOL) for cancer patients. 12. Finally, oriental medical cancer center must be constructed in NCC (National Cancer Center) or government agency for the development of oriental medical oncology which has international competitive power.

A Study on the Current Rotation System of Hunting Ground (현행(現行) 순환수렵장(循環狩獵場) 제도(制度)에 관(關)한 연구(硏究))

  • Byun, Woo Hyuk
    • Journal of Korean Society of Forest Science
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    • v.74 no.1
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    • pp.47-55
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    • 1986
  • During the past 4 years, I have made a careful analysis of the present rotating system of hunting areas, on the one hand, by asking a group of hunters to fill out a questionnaire, and on the other hand, by referring to the written documents on the subject. And, as a result, it is concluded that this system, by varying the hunting grounds each year, contains in itself several problems as follows. 1. The hunters find it quite inconvenient to use a different hunting ground year after year and they also complain that the present hunting ground charge is more than it is worth. Therefore, it is expected that the number of hunters will explosively increase in the future with the betterment of hunting conditions. 2. The hunters have almost no information about game and they are, as a whole, lacking in the ethics of hunting. 3. The allotment of time in hunting training courses is not so sufficient that it is next to impossible to improve the quality of hunters. 4. As a rule, the population density of wildlife is so sparse that it falls short of the proper standard of it. 5. The present hunting system does not seem to contribute to the advancement of tourism. 6. It is absolutely necessary to make a general survey of the situation of wildlife for the legal protection of it. Besides, the interests of hunters are so closely tied up with those of farmers and foresters that dreastic measures should be taken to settle their conflicting differences. For the purpose of solving the above-mentioned problems and at the same time, of developing sound hunting practices in the long run, I hereby make two suggestions. 1. The Establishment of the Hunting License Test System It is desirable to issue a license to a prospective hunter after he has met a special qualification and then passed a test so that he may have bits of information needed for his hunting activities. 2. The Introduction of The Revier System The fundamental concept of this system is based on the assumption that the private landowner should reserve a right to the pursuit of game and take responsibility for wildlife management.

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Effect of Various Fruit-loads on Yield, Fruit Quality and Growth of 'Seolhyang' Strawberry (착과 정도가 '설향' 딸기의 수량, 과실 품질 및 생육에 미치는 영향)

  • Lee, Sang Woo;Hwang, Gap Choon;Yun, Jae Gill;Hong, Jeum Kyu;Park, Soo Jeong
    • Journal of Bio-Environment Control
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    • v.23 no.3
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    • pp.205-211
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    • 2014
  • This study aimed to examine the effect of different fruit-loads on fruit yield, quality, and plant growth of 'Seolhyang' strawberry. Fruit loads were adjusted from the first to the fourth flower cluster so that the number of fruits became 20, 25, and 30, and non-flower thinning of some was made. The more the number of fruits per plant was, the greater the total yield obtained, but marketable yield decreased and non-marketable yield increased. Compared to the treatment whose fruit load was adjusted, the control with non-flower thinning had more fruit yield in the first and second flower clusters but tended to have less fruit yield in the third and fourth flower clusters. The lower the fruit load was, the more soluble solids content of fruits increased. The lower the fruit load of a flower cluster was, the faster its harvest time reached. Harvest of fruit load of 20 was faster by 10 days in the second and fourth flower clusters relative to the control. On November 24, 2012, flowering thinning of the first flower cluster was made. On March 7, 2013, fruit dry weight of the second flower cluster was most heavy in the control. Dry weight of roots decreased in the control and the fruit load of 30 compared to November 24. On April 9, fruit dry weight of the third flower cluster did not have significant difference according to fruit load, however the more the fruit load was, the smaller dry weight of leaf, root, and crown became, which were vegetative organs. On May 12, the more the fruit load, the smaller leaf area and dry weight of vegetative organs and differences from varying fruit-loads became considerable in later period of growth. Appropriate fruit load of 'Seolhyang' strawberry were from 20 to 25. Maintaining balance between vegetative and fruit growth by adjusting fruit load is very important for stable fruit production.

Effects of Diet and Time on Feed on Fatty Acid Composition in Muscle of Charolais Steers (사료급원과 급여기간이 Charolais 거세우 근내 지방산 조성에 미치는 영향)

  • 최낙진;강수원;권응기;조원모;전병수;박병기
    • Journal of Animal Science and Technology
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    • v.48 no.6
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    • pp.847-860
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    • 2006
  • This study investigated the effects of feeding Charolais steers on diets rich in either n-6 or n-3 polyunsaturated fatty acids (PUFA) and time on feed (TOF) on muscle fatty acid composition and content. Twenty eight steers were fed on ad libitum forage and one of two concentrates varying in the source of fat; soya (high in C18:2 n-6) or whole linseed (high in C18:3 n-3) for either 60 or 90 days in IGER (Institute of Grassland and Environmental Research, UK). The concentrates were fed at approximately 0.73 of total DM intake. TOF influenced carcass weight, conformation and fatness scores, which were higher at 90 v. 60 days (P<0.05). Diet did not affect total fatty acid content of neutral lipid in m. longissimus thoracis but feeding linseed increased total phospholipid fatty acid by approx- imately 15%(P<0.05). Linseed increased the amount and proportion of C18:3 n-3 (P<0.001) and the proportion of CLA (cis-9, trans-11 conjugated linoleic acid), while soya increased the content (P<0.05) and proportion (P<0.001) of C18:2 n-6 in muscle neutral lipid. In muscle phospholipid, linseed significantly increased the amount of CLA, C18:3 n-3 and its longer chain derivatives as well as C14:0, C16:0, C18:0. C18:1 trans and C18:2 n-6. The amount and proportion of C18:2 n-6 and its longer chain C20 derivatives were higher on feeding soya. TOF (90 v. 60 day) increased the content of C14:0, C16:0, C16:1, CLA, C18:1 n-9, C18:2 n-6 and C18:3 n-3 in muscle neutral lipid. The P:S was not affected by diet or TOF. The ratio of C18:2 n-6 : C18:3 n-3 and sum of n-6 : n-3 fatty acids were higher in muscle from animals fed on linseed v. soya (P<0.001). The study indicates that the PUFA composition of beef muscle may be significantly modified by feeding contrasting dietary lipids, soya vs. linseed. Feeding linseed produced a better balance of muscle fatty acids, more in line with current nutritional recommendations with a lower C18:2 n-6:C18:3 n-3 ratio associated with higher muscle content of C18:3 n-3 and C20:5 n-3 and CLA and lower C20:4 n-6.

Composting of Livestock Waste and Development of Operating Parameters I. Development of Optimum Process Parameters in Cow Manure Composting (축산 폐기물의 퇴비화 및 운용지표 개발 I. 우분의 퇴비화에 있어서 최적 공정운용지표의 개발)

  • Chung, Jae-Chun
    • Journal of the Korea Organic Resources Recycling Association
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    • v.1 no.1
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    • pp.69-84
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    • 1993
  • In order to determine the optimum operational paramsters in cow manure composting, 4 laboratory scale composters were established. The cow manure was mixed with certain amount of saw dust to adjust the initial C/N ratio to 24, initial pH to 6.9 and composting was performed with varying operational conditions. It was found that the optimum aeration rate was 1000 ml/min kg. VS, the optimum moisture content 50% and no significant difference was found with different initial pH condition. Microorganisms were counted under the optimum conditions determined in this study. At the end of the experimental period, the number of bacteria, actinomycetes and fungi was $1.5{\times}10^9$ cells, $1.1{\times}10^8$ cells and $3.0{\times}10^8$ cells/g dry compost, respectively. At day 0, the number of coliforms, fecal coliforms and fecal streptococci was $3.1{\times}10^3$ cells, $7.5{\times}10^2$ cells and $5.6{\times}103$ cells/g dry composting material, respectively. Their population was decreased with time lapse, However, their survival time was longer than those reported by other researchers. Microorganisms were identified at the end of the experiment. Genus Bacillus was the most dominant comprising 89.3% of the total population. Among the Genus Bacillus, B. circulans compoex was the most abundant, followed by B. Stearothermophilus, B. Sphericus, B. licheniformis and B, brevis.

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Effect of Low-Level Laser to Oral Microorganisms (저출력 레이저가 구강미생물에 미치는 영향)

  • Yoon, In-Jong;Auh, Q-Schick;Chun, Yang-Hyun;Hong, Jung-Pyo
    • Journal of Oral Medicine and Pain
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    • v.35 no.1
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    • pp.31-39
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    • 2010
  • This study is to observe the bacteriocidal effect of the Low Level Laser (LLL) against oral microorganisms which are related to the occurrence of periodontal diseases and oral malodors. The Porphyromonas gingivalis 2561 (P. gingivalis 2561) and Prevotella intermedia (Pr. intermedia) were treated with photosensitizing substance-toluidine blue O (TBO; C.I. 52040) and then radiated with the LLL which has 650nm wavelength for 1, 2, 3 and 5mins. continuously upon varying distances of 1, 2 and 3cm for each experimental groups. The results are as follows; 1. The P. gingivalis 2561 which was treated with TBO and then radiated with LLL at a distance of 3cm for 1min. showed 99.99% higher antibacterial effect in comparison to the experimental group treated only with TBO. 2. The Pr. intermedia which was treated with TBO and then radiated with LLL at a distance of 3cm for 1min. showed 99.8% higher antibacterial effect in comparison to the experimental group treated only with TBO. 3. The bacteriocidal effect of the P. gingivalis 2561 treated with TBO was found to gradually increase as the radiation time of LLL extended from 1min. to 3min. at 1min. intervals. 4. A slight decrease in bacteriocidal effect of the P. gingivalis 2561 was found as the radiation distance of LLL increased from 1cm to 3cm at 1cm intervals. 5. The bacteriocidal effect of the Pr. intermedia was found to slightly decrease as the radiation distance of LLL increased from 1cm to 3cm at 1cm. intervals. As the results shown above suggest, the bacteriocidal effect of LLL was found to increase as the radiation time extended and the distance shortened. Moreover, even the experimental group radiated with LLL at 3cm distance for 1min. which showed the lowest level of bacteriocidal effect, was found to have 99.8% higher bacteriocidal effect than the experimental group which was treated only with TBO and, therefore, this clearly shows the bacteriocidal effect of LLL against oral microorganisms. Thus, the use of LLL is thought to become very useful for suportive treatment for periodontitis and implantitis, and controlling oral malodors as long as it is used within the limits where there is no side effect.