• Title/Summary/Keyword: size-dependent

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MECHANISM IN ANTIBACTERIAL ACTIVITY OF POLYPHOSPHATES AGAINST PORPHYROMONAS ENDODONTALIS (Porphyromonas endodontalis에 대한 Polyphosphate의 항균기전에 관한 연구)

  • Choi, Sung-Baik;Park, Sang-Jin;Choi, Gi-Woon;Choi, Ho-Young
    • Restorative Dentistry and Endodontics
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    • v.25 no.4
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    • pp.561-574
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    • 2000
  • Poly-P has been used to prevent decomposition of foods and has been shown to have inhibitory effect on the growth of gram positive bacteria. The purpose of this study was to evaluate the effect of poly-P on the growth of Porphyromonas endodontalis, a gram negative obligate anaerobic rod, endodontopathic bacterium. P. endodontalis ATCC 35406 was in BHI broth containing hemin and vitamin K with or without poly-P. Inhibitory effect of each poly-P which was added at the beginning(lag phase) or during(exponential phase) the culture, MIC(minimum inhibitory concentration) was determined by measuring the optical density of the bacterial cell at 540nm. Viable cell counts were measured to determined whether poly-P has a bactericidal effect. Leakage of intracellular nucleotides from P. endodontalis was determined at 260nm and morphological change of P. endodontalis was observed under the TEM(transmission electron microscope). Binding of 32P-labeled poly-P to P. endodontalis was examined. SDS-polyacrylamide gel electrophoresis and zymography were performed to observe the changes in protein and enzyme profiles of P. endodontalis, respectively. The results from this study were as follows : 1. The minimal inhibitory concentration(MIC) of poly-P to P. endodontalis appeared to be 0.04~0.05%. 2. Poly-P added to the P. endodontalis culture during the exponential phase of P. endodontalis was as much effective as poly-P added at the begining of the culture, suggesting that the antibacterial effect of poly-P is not much dependent on the initial inoculum size of P. endodontalis. 3. Poly-P are bactericidal to P. endodontalis, demonstrating the decrease of the viable cell counts. 4. Intracellular nucleotide release from the P. endodontalis, was not increased in the presence of poly-P and was not reversed by the addition of divalent cations like $Ca^{2+}$ and $Mg^{2-}$. 5. Under the TEM, it was observed that fine electro-dense materials were prominent in the poly-P grown P. endodontalis, appearing locally in the cell, and the materials were more abundant and more dispersed in the cell as the incubation time with poly-P increased. In addition, highly electron dense granules accumulated in many poly-P grown cells, most of which were atypical in their shape. 6. Binding of 32P-labeled poly-P to P. endodontalis appeared to be 32.8 and 45.5 and 53.4% at 30 minutes, 1 hours and 2 hours, respectively. 7. In the presence of poly-P. the synthesis of proteins with apparent molecular masses of 25, 27, 35, 45 was lost or drastically decreased whereas expression of a protein with an apparent molecular mass of 75 was elevated. 8. Proteolytic activity of P. endodontalis was decreased by poly-P. The overall results suggest that use of poly-P may affect the growth of P. endodontalis, and the anti-bacterial activity of poly-P seems largely bactericidal. Changes in shape, protein expression, and proteolytic activity of P. endodontalis by poly-P may be directly and indirectly attributed to the antibacterial effect of poly-P. Further studies will be needed to confirm the effect of poly-P.

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A Study on the Efficiency of Hand-Knee Position in GB Stone Ultrasonography (담낭결석 초음파검사에서 Hand-Knee position의 효율성에 관한 연구)

  • Park, Soung-Ock;Do, Yun-Su
    • Journal of radiological science and technology
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    • v.29 no.4
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    • pp.267-274
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    • 2006
  • The evaluation of GB stones with ultrasound has proved to be useful procedure in patient with symptoms of cholelithiasis. GB is evaluated for size, wall thickness, presence of internal reflections within the lumen and posterior acoustic shadowing or enhancement in Ultrsonography. The patient position should be shifted during procedure to demonstrate further the presence of stone within the GB. Patient scanned at the Rt. subcostal region in supine, right lateral, Lt. down decubitus, and upright sitting position. So GB stone should shift to dependent area of GB. Often, GB is not markedly distended in the presence of cholethiasis, and so the diagnosis becomes more difficult. One of the more difficult areas for detection of a GB stones are embeded in the cystic duct region. And since the GB is adjacent to the duodenum and hepatic flexure, its may be difficult to visualizing a GB stone. When patient study position changes frome supine to other position, stones displaced the site. But if its are polyps, not changes the site whatever patient positions. It is very important to what make different GB stones or polyps. We have studied about mobility of GB stones according to the patients position(supine, Lt. down decubitus, $30^{\circ} LAO. sitting and hand-knee). So we have a result, stones wherever localized within the GB, changed 100% its position in the hand-knee position and the others appeared at least 90%. In this study, when a large stones are located through fundus-body and body-neck, does not changing the stones position in spite of varied patient's positions. But hand-knee positions can identified GB stones, because its make changed the position of stons from posterior wall to anterior wall within the GB. We recommend the hand-knee position for differentiation GB stones from polyps.

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Fabrication of Backscatter Electron Cones for Radiation Therapy (산란전자선을 이용한 강내측방조사기구의 제작과 특성)

  • Chu, Sung-Sil;Suh, Chang-Ok;Kim, Gwi-Eon
    • Radiation Oncology Journal
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    • v.19 no.1
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    • pp.74-80
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    • 2001
  • Purpose : Irradiation cones by using backscatter electrons are made for the treatment of superficial small lesions of skin, oral cavity, and rectum where a significant dose gradient and maximum surface dose is desired. Methods and Materials : Backscatter electrons are produced from the primary electron beams from the linear accelerators. The design consists of a cylindrical cone that has a thick circular plate of high atomic number medium (Pb or Cu) attached to the distal end, and the plate can be adjusted the reflected angle. Primary electrons strike the metal plate perpendicularly and produce backscatter electrons that reflect through the lateral hole for treatment. Using film and a parallel plate ion chamber, backscatter electron dose characteristics are measured. Results : The depth dose characteristic of the backscatter electron is very similar to that of the hard x-ray beam that is commonly used for the intracavitary and superficial lesions. The basckscatter electron energy is nearly constant and effectively about 1.5 MeV from the clinical megavoltage beams. The backscatter electron dose rate of $35\~85\;cGy/min$ could be achieved from modern accelerators without any modification. and the depth in water of $50\%$ depth dose from backscatter electron located at 6mm for $45^{\circ}$ angled lead scatter. The beam flatness is dependent on the slit size and the depth of treatment, but is satisfactory to treat small lesions. Conclusions : The measured data for backscatter electron energy, depth dose flatness dose rate and absolute dose indicates that the backscatter electrons are suitable for clinical use.

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Application of a New Conjugation Method to Fish Pathogenic Bacteria Containing R Plasmid for the Analysis of Drug-Resistant Status in Aquaculture (새로운 conjugation 방법을 응용한 R plasmid 함유 어병세균의 분리와 양식장 내성균의 현황 분석)

  • Yoo Min Ho;Jeong Joon Beom;Kim Eun Heui;Lee Hyoung Ho;Jeong Hun Do
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.2
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    • pp.115-121
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    • 2002
  • To develop a new method of conjugation and to determine the distribution of R plasimds, we isolated multi-drug resistant strains from fish pathogenic bacteria in the farms of south and east seacoasts of Korea. Out of the 134 isolates examined, 10 showed resistance to chloramphenicol, tetracycline, streptomycin, ampicillin, colistin, nalidixic acid, oxolinic acid and kanamycin. One out of 10 multi-drug resistance bacteria, Vibfio damsela JE1 (V. damsela JE1), contained transferable R plasmid of chlorarnphenicol- tetracycline resistance genes and other nucleic acids encoding ampicillin and kanamycin resistance. The presence of the R plasmid was confirmed by conjugation using the chromocult medium (CC) as a selective and differential medium for transconiugants with identification based on the growth or colors of the colonies. The frequency of R plasmid transfer with filter mating method was come out much higher than that of broth mating method and appeared to be dependent upon the mating time and temperature. The optimum conditions for filter mating method were found to be 30$^{\circ}C$ and 24hrs as mating temperature and period, respectively, Moreover, donor cells with R plasmid, both isolate and standard bacteria, were shown to have an ability to transfer the plasmid against Escherichia coli K-12 HB101 (E. coli HB101) and Edwardsiella tarda (E. tarda) RE14 at fairly high frequencies, finally, we isolated 3 isolates of Sphingomonas sp., carrying R plasmid from 12 multi-drug resistant bacteria in normal microflora of the flounder (Paralichthys olivaceus) group used for the isolation of V emsela JE1 four months before. The same size and gene transfer chayateristics of R plasimds with those of V damsela JE1 confirmed that normal microflora have the reservoir activity for R plasmid in natural aquatic environment.

Effects of Vegetable Sprout Power Mixture on Lipid Metabolism in Rats Fed High Fat Diet (새싹채소 혼합분말이 고지방 식이를 급여한 흰쥐의 지질대사에 미치는 영향)

  • Lee, Jae-Joon;Lee, Yu-Mi;Shin, Hyoung-Duck;Jeong, Young-Sim;Lee, Myung-Yul
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.8
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    • pp.965-974
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    • 2007
  • This study was performed to investigate the effects of vegetable sprout powder on serum and adipose tissue lipid metabolism in rats fed high-fat diet for 4 weeks for induction hyperlipidemic model rat. Weight-matched male Sprague-Dawley rats were assigned to five groups according to dietary fat level (10% or 20% of diet wt.) and mixture of vegetable sprout powder levels (5% or 10% 10% or 20% of diet wt.). Vegetable sprout powder was the mixture of same amounts of dried barley, broccoli, rapeseed, alfalfa, radish, mustard, buckwheat and brussels sprouts. Experimental groups were normal fat diet with 5% cellulose (NF-C), high fat diet without fiber (HF-N), high fat diet with 5% cellulose (HF-C), HF-C diet with 5% vegetable sprout powder (HF-CSL), and HF-C diet with 10% vegetable sprout powder (HF-CSH). The body weight of HF-N group increased 16% compared with the NF-C group, while it was decreased by 15% and 22% for HF-CSL group and HF-CSH group, respectively. Fat mass and fat cell size of adipose tissue were lower in HF-CSL group and HF-CSH group compared with HF-C group, and lower in HF-CSH group compared with HF-CSL group. Serum triglyceride, total cholesterol and LDL-cholesterol contents were markedly decreased by vegetable sprout powder containing diet, while the serum HDL-cholesterol and phospholipid contents were higher in vegetable sprout powder containing diet in a dose-dependent manner. Leptin and insulin levels in serum showed a decrease in HF-CSH group. Significantly increased contents of triglyceride, total cholesterol, LDL-cholesterol, leptin and insulin in the serum of HF-N group were returned to normal or even below normal levels by feeding 10% vegetable sprout powder diet. The increased activities of NADP-malate dehydrogenase (ME), glucose-6-phosphate dehydrogenase (G6PDH) and 6-phosphogluconate dehydrogenase (6PGDH) and lipoprotein lipase (LPL) in adiposetissue by HF-N group were decreased to the activity of normal fat group by feeding vegetable sprout powder in a dose-dependant manner. These results indicate that lipid metabolism in rats fed high-fat diet was suppressed by feeding vegetable sprout powder.

The effect of 8 French catheter and chest tube on the treatment of spontaneous pneumothorax (자연기흉에 있어서 8 French 도관과 흉관의 삽입 치료 효과)

  • Kang, Yoon-Jeong;Koh, Hyoung-Gee;Shin, Jong-Wook;Lim, Seong-Yong;Choi, Jae-Sun;Yu, Ji-Hoon;Park, In-Won;Choi, Byoung-Whui;Hue, Sung-Ho;Seo, Seung-Cheon
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.3
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    • pp.410-419
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    • 1996
  • Background : Spontaneous pneumothorax have been managed with a variety of methods. The technique most frequently used is chest tube drainage. Small caliber catheters were first used in the management of pneumothorax complicating the percutaneous needle aspiration lung biopsy, and the try to treat spontaneous pneumothorax also has been reported. However, the value of small caliber catheters in spontaneous pneumothorax has not been fully evaluated. So, we tried to elucidate the efficacy of 8 French catheter in the management of spontaneous pneumothorax. Method : From January, 1990, to April, 1994, 44 patients with spontaneous pneumothorax treated at Chung-Ang university hospital were reviewed. The patients were sub-divide into 8 French catheter insertion group (n=21) and chest tube insertion group (n=23). We compared the presence of underlying lung disease, the extent of the collapse, the duration of indwelling catheter and complication between two groups. Results : 1) The duration of indwelling showed no significant difference between 8 French catheter group and chest tube. But, complication after insertion as subcutaneous emphysema was developed in only chest tube group. (p<0.05) 2) In the primary spontaneous pneumothorax, all case of the pneumothorax of which size was less than 50% showed complete healing with 8 French catheter insertion. Whereas the success rate in patients with large pneumothorax (more than 50%) was tended to be dependent on the age. 3) In the patients with secondary spontaneous pneumothorax who were managed with 8 French catheter, the success rate was trended to be high if the underlying disease of pneumothorax was not COPD and if the patient was young. Conclusion : These results show that 8 French catheter insertion probably was effective in the pneumothorax less than 50%, the primary spontaneous pneumothorax, young age or secondary pneumothorax not associated with COPD.

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Propagation Efficiencies at Different LED Light Qualities for Leaf Cutting of Six Echeveria Cultivars in a Plant Factory System (에케베리아 6품종의 엽삽 시 식물공장시스템 내 LED 파장에 따른 번식 효율)

  • Kim, Seongmin;Kim, Jiseon;Oh, Wook
    • Journal of Bio-Environment Control
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    • v.27 no.4
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    • pp.363-370
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    • 2018
  • The succulent plants of Echeveria genus are in increasing demand worldwide, but it is difficult to supply good quality young plants throughout the year because propagation efficiencies are depend on cultivar and environmental factors. This study was carried out to investigate the propagation efficiencies of leaf cutting in Echeveria cultivars at different LED light qualities in a closed-type plant factory system. Leaf cuttings cut from stock plants of six difficult-to-propagated cultivars 'Afterglow (AG)', 'Berkeley Light (BL)', 'Mason (MS)', 'Subsessilis Light (SL)', 'Cream Tea (CT)', and 'Ben Badis (BB)' were put into cutting media in the plant factory system maintained at a temperature of $24{\pm}2^{\circ}C$ and relative humidity of $60{\pm}10%$, and watered with over-head irrigation twice a week. Cuttings were irradiated with sole or mixed red (R, 660 nm), blue (B, 450 nm), green (G, 530 nm), and far-red (FR, 730 nm) LEDs as follows: R10, R8+B2, R5+B5, R7+B2+FR1, and R7+B2+G1. PPFD just above the cuttings was $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and photoperiod was 16/8 (light/dark) hours. As a result, propagation efficiencies were dependent on cultivar. Rooting and shooting were relatively easy in 'SL' but shoot formation in 'AG' was very difficult. Light qualities from LEDs also affected plant regeneration. Light conditions with a higher ratio of B, R5+B5, R7+B2+FR1, and R7+B2+G1, promoted shoot formation and growth but inhibited rooting and root growth. R10 and R8+B2 with a higher ratio of R promoted rooting and root growth and inhibited shoot formation and growth of cuttings. In addition, the treatment with FR increased leaf size and biomass of the all plants. Therefore, further studies are needed to investigate the optimum compositions of LED light quality for the improvement of leaf cutting efficiency in difficultto-propagated Echeveria cultivars.

The Effect of Quinolyl Piperazine Phosphate on the Silicotic Rats (Quinolyl Piperazine Phosphate가 흰쥐 규폐증에 미치는 영향)

  • Yim, Hyeon-Woo;Jung, Chang-Young;Oh, Sang-Yong;Kim, Kyung-Ah;Lim, Young;Yun, Im-Goung;Roh, Young-Man
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.2
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    • pp.112-122
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    • 1993
  • Backgrounds : The goal of drug therapy in pneumoconiosis is to inhibit the progression of pulmonary fibrosis related to a toxic effect of the inhaled substance. Although there have been many studies on the therapy of pneumoconiosis, it is still elusive. Quinolyl piperazine phosphate (QP), a derivative of chloroquine, is less toxic, more effective, and longer action than chloroquine. This investigation was performed to examine the effect of the quinolyl piperazine phosphate in silicotic rats. Methods : The silica group was administered intratracheally by 40 mg free silica dust with 0.5 ml normal saline, and the QP group was orally administered QP 10 mg per week after free silica instillation. The animals in the silica group and the QP group were killed at the 1st, 3rd, 8th and 20th week after free silica instillation. We observed the total cell count in bronchoalveolar lavage fluid, luminol-dependent chemiluminescence by viable alveolar inflammatory cells, the dry weights and the amount of hydroxyproline in the left lung and the histopathologic examination in the right lung. Results : 1) The total number of cells of bronchoalveolar lavage fluid in the QP group tended to be decreased in comparison with the silical group. But, It was not significant. 2) Luminol-induced chemiluminescence by viable alveolar inflammatory cells in the QP group was similiar to that in the silical group. 3) The dry weights in the left lung at the 3th and 8th week in the QP group were significantly decreased compared to the silical group. 4) The total amount of hydroxyproline at the 3rd week of the QP group were significantly decreased compared to the silical group. In the silica group, the total amount of hydroxyproline was significantly increased at the 3rd week compared with the 1st group. But, in the QP group, it was significantly increased at the 8th week. 5) In tissue pathology, the infiltration of inflammatory cells around bronchiole, and the number and the size of silicotic nodule in the QP group were similar to the silica group. But, the extent of fibrosis is less than the silica group. Especially we observed progressive massive fibrosis which located in the periphery in 3 cases among the silica group, but couldn't observe in the QP group. Conclusions : QP doesn't significantly suppress the pulmonary fibrosis consequent to the intratracheal instillation of free silica dust, but delay the progression of fibrosis.

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Regional Variations in the Cesarean Section Rate and It's Determinants in Korea (제왕절개 분만율의 지역간 변이와 관련요인에 대한 연구)

  • Kim, Hye-Kyung;Lee, Jeon-Un;Park, Kang-Won;Moon, Ok-Ryun
    • Journal of Preventive Medicine and Public Health
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    • v.25 no.3 s.39
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    • pp.312-329
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    • 1992
  • The purpose of this study is to estimate cesarean section rate in Korea and analyze the socioeconomic variables and health resources which affect regional variation in the rate. Samples were drawn from the record of vaginal and cesarean section deliveries based upon insurance claim bills which have been submitted to the National Federation of Medical Insurance for the first three months, January through March, 1991. The results are obtained as follows : It was found that. cesarean section rate was increasing rapidly up to 23.1% in 1991. Cesarean section per 10 thousand insured people was 4.8 and the number of cesarean section per 10 thousand insured eligible($15{\sim}49$ years old) female was 7.6. The fee for normal delivery was 109,489 won and that for cesarean section was 390,024 won. The average days of hospitalization in normal delivery was 2.3 days, and those in cesarean section was 7.6 days. On the average cesarean section has a longer of stay as much as by 4.3 days and cost 3.6 times more than normal deliveries. Cesarean section rates vary among medical facilities 19.8% at clinics 37.6% in small-scale hospitals, and 29.1% in general hospitals. The regional variation of cesarean section rates was also fairly prominent. The South Cheju Gun has the highest rate of cesarean section, 56.2%. Meanwhile no cesarean section cases has been reported in Sunchang Gun during the period of this study. The variation is noted among provinces. The rate for Cheju province has been 3.4 times higher than that for Chunnam. The number of cesarean section per 10 thousand insured people vary greatly among regions, too. This study has found that there exists significant regional variations among various geographic units in terms of average length of stay, average cost, number of obsretricians and number of beds. Multiple regression analysis was done to identify factors explaining the regional variance of various cesarean section rates : In the urban areas, no significant explaining variables were noted except the number of beds for the dependent variable of cesarean section cases per 10 thousand insured eligible females. The smaller the number of bed, the more cases of cesarean section was noted for an urban area. The is mostly because the rate of cesarean section is higher in medium-size hospitals than in large general hospitals. In the rural areas, the factor of education has been found significant for all three deplendent variables. The higher the educational level, the rate of cesarean section is most likely to rise. An income variable measured by the amount of monthly insurance contribution has been identified a powerful predictor in explaining the valiance of cesarean section rates. The same has been noted for the number of obstetricians. Similar findings are observed for the country as a whole. The income level has veen found as the most powerful explaining factor in the regional variance of cesarean section rates. In general the rate is higher in the urban areas, and lower in the area with more small hospitals. As this is the initial attempt to identify the factors relevant to the regional difference in the rates of cesarean section, more elaborated study is urgently required.

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Least-Square Fitting of Intrinsic and Scattering Q Parameters (최소자승법(最小自乘法)에 의(衣)한 고유(固有) Q와 산란(散亂) Q의 측정(測定))

  • Kang, Ik Bum;McMechan, George A.;Min, Kyung Duck
    • Economic and Environmental Geology
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    • v.27 no.6
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    • pp.557-561
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    • 1994
  • Q estimates are made by direct measurements of energy loss per cycle from primary P and S waves, as a function of frequency. Assuming that intrinsic Q is frequency independent and scattering Q is frequency dependent over the frequencies of interest, the relative contributions of each, to a total observed Q, may be estimated. Test examples are produced by computing viscoelastic synthetic seismograms using a pseudo spectral solution with inclusion of relaxation mechanisms (for intrinsic Q) and a fractal distribution of scatterers (for scattering Q). The composite theory implies that when the total Q for S-waves is smaller than that for P-waves (the usual situation), intrinsic Q is dominating; when it is larger, scattering Q is dominating. In the inverse problem, performed by a global least squares search, intrinsic $Q_p$ and $Q_s$ estimates are reliable and unique when their absolute values are sufficiently low that their effects are measurable in the data. Large $Q_p$ and $Q_s$ have no measurable effect and hence are not resolvable. Standard deviation of velocity $({\sigma})$ and scatterer size (A) are less unique as they exhibit a tradeoff as predicted by Blair's equation. For the P-waves, intrinsic and scattering contributions are of approximately the same importance, for S-waves, the intrinsic contributions dominate.

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