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Cross-resistance Between Rifampicin and Rifabutin and Its Relationship with rpoB Gene Mutations in Clinically Isolated MDR-TB Strains (다제내성 결핵 균주에서 리팜핀과 리파부틴간의 교차내성률 및 rpoB 유전자 돌연변이와의 연관성)

  • Kim, Byoung Ju;Oh, Seung Hwan;Cho, Eun Jin;Park, Seung Kyu
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.2
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    • pp.171-179
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    • 2006
  • Background : Despite the emerging danger of MDR-TB to human beings, there have only been a limited number of drugs developed to treat MDR-TB since 1970. This study investigated the cross-resistance rate between rifampicin (RFP) and rifabutin (RBU) in order to determine the efficacy of rifabutin in treating MDR-TB. In addition, the results of rifabutin were correlated with the rpoB mutations, which are believed to be markers for MDR-TB and RFP resistance. Methods : The MICs of RBU were tested against 126 clinical isolates of MDR-TB submitted to the clinical laboratory of National Masan TB Hospital in 2004. Five different concentrations ($10-160{\mu}g/ml$) were used for the MICs. The detection of the rpoB mutations was performed using a RFP resistance detection kit with a line probe assay(LiPA), which contains the oligonucleotide probes for 5 wide type and 3 specific mutations (513CCA, 516GTC, and 531TTG) The rpoB mutation was determined by direct sequencing. Results : The rate of cross-resistance between RFP and RBU was 70.5%(74/105) at $20{\mu}g/ml$ RBU(ed note: How much RFP?) Most mutations (86.3%) occurred in the 524~534 codons. The His526Gln, His526Leu, Leu533Pro, Gln513Glu, and Leu511Pro mutations(Ed note: Is this correct?) were associated with the susceptibilty to RBU. Conclusion : Based on the cross-resistance rate between RFP and RBU, RBU may be used effectively in some MDR-TB patients. Therefore, a conventional drug susceptibility test for RBU and a determination of the critical concentration are needed. However, rpoB gene mutation test may be have limited clinical applications in detecting RBU resistance.

The Effect of Au Addition on the Hardening Mechanism in Ag-25wt% Pd-15wt% Cu (Ag-25wt% Pd-15wt% Cu 3원합금(元合金) 및 Au 첨가합금(添加合金)의 시효경화특성(時效京華特性))

  • Bea, B.J.;Lee, H.S.;Lee, K.D.
    • Journal of Technologic Dentistry
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    • v.20 no.1
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    • pp.37-49
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    • 1998
  • The specimens used were Ag-25 Pd-15 Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electric furnace and centrifugal casting machine in Ar atmosphere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age- hardening characteristics of the small Au-containing Ag-Pd-Cu dental alloys were investigated by means of hardness testing. X-ray diffraction and electron microscope observations, electrical resistance, ergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, i.e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the $L1_0$ type face-centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affected by the Cu concentration. In stage II, decomposition of the ${\alpha}$ solid solution to a PdCu ordered phase($L1_0$ type) and an Ag-rich ${\alpha}2$ phase occurred and a discontinuous precipitation occurred at the grain boundary. From the electron microscope study, it was conclued that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipetation procedure was ${\alpha}{\to}{\alpha}+{\alpha}_2+PdCu {\to}{\alpha}_1+{\alpha}_2+PdCu$ at Pd/Cu = 1.7 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.

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Comparison of the Clinical and Radiologic Characteristics between Different Age Groups with First Febrile UTI Under 2 Years of Age (2세 미만 소아의 첫 발열성 요로 감염에서 연령군에 따른 발병양상 및 영상의학적 검사 결과의 비교)

  • Coe, Hee-Jung;Kim, Tae-Hyung;Cho, Hyuk;Kim, Ji-Hong
    • Childhood Kidney Diseases
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    • v.11 no.2
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    • pp.229-238
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    • 2007
  • Purpose : Since the first febrile UTI(urinary tract infection) in infants is commonly associated with vesicoureteral reflux(VUR), imaging studies such as renal ultrasonography, dimercaptosuccinic acid(DMSA) scan, and voiding cystourethrography(VCUG) are recommended. How-ever, because of the invasiveness of VCUG, it is difficult to perform in all young infants with febrile UTI. The purpose of this study is to compare the clinical and laboratory characteristics, radiologic findings between the young infant group(1 to 6month, n=121) and the old infant group(7 to 24months, n=91), and to determine the clinical and radiologic risk factors that predict the presence of VUR before the VCUG in patients with their first febrile UTI under 2 years of age. Methods : We reviewed the medical records of 211 first febrile UTI patients under 2 years of age retrospectively, and compared clinical, laboratory, and radiologic findings between the two age groups. Results : The young infant group had a male preponderance and a higher incidence of Escherichia coli in their urine culture. The incidence of acute renal parenchymal defects on DMSA scans were significantly increased in the young infant group. The incidence of VUR was 29% in patients who had a VCUG, but there were no differences in the incidence of VUR between the two age groups. Abnormal findings on DMSA scan significantly correlated with higher incidence of VUR in the young infant group. Incidence of abnormal findings DMSA scan significantly increased with high grade VUR(garde III-V ). Conclusion : In treating first febrile UTI patients under 2 years, physicians have to consider such characteristics as age less than 6 months, male preponderance, E.coli in the urine culture, and increased incidence of abnormal findings on DMSA scans which correlated well with the presence of VUR. The results of the DMSA scan might help us to predict the presence of VUR before the VCUG in first febrile UTI and help us to reduce performing invasive radio-logic studies especially in the young infant group. (J Korean Soc Pediatr Nephrol 2007;11:229-238)

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Varietal Response of Tobacco Plants Through Tissue Culture to Butachlor and Bialaphos Herbicides (조직배양(組織培養)에 의한 제초제(除草劑) Butachlor와 Bialaphos에 대(對)한 담배의 품종간반응(品種間反應))

  • Bae, Y.Z.;Kim, K.U.;Jeong, H.J.
    • Korean Journal of Weed Science
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    • v.8 no.1
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    • pp.53-58
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    • 1988
  • This study was carried out to determine effect of butachlor [N.-(buthoxymethyl)-2-chloro-N-(2,6-diethylphenyl) acetamide] and bialaphos [2-amino-4(hydroxy)(methyl) phosphionyl] butyryl-alanylalanine sodium salt on the germination of tobacco seed, induction and growth of callus from tobacco. Further, fatty acids and ammonia content of tobacco calli were determined. Bialaphos had no effect on tobacco seed germination, but the growth of seedling was markedly affected by an application of 10 ppm bialaphos. However, regardless of varieties tested, tobacco seed germination was completely inhibited by $5{\times}10^{-5}M$ of butachlor. At an application of $5{\times}10^{-5}M$ butachlor, tobacco seeds were to some extent germinated and showed further growth. Hyangcho among varieties tested, showed the most tolerant response to butachlor. In induction of callus from various tobacco varieties and their growth, aromatic type of tobacco varieties exhibited the most tolerance against bialaphos. However, no distinct varietal differences were determined in the treatment of butachlor. The major fatty acids identified in tobacco calli were palmitic, oleic and linoleic acid. No marked difference in terms of fatty acids was observed among tobacco varieties used, but it was observed that there was the higher ratio of quantity in unsaturated fatty acids over saturated one, bialaphos treatment accumulated about 9 times higher ammonia content than that of the untreated control, giving an evidence that bialaphos might inhibit glutamine synthetase activity.

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Anatomical Difference in Selectivity between Paddy Rice and Weed Species by Mixture Use of Oxyfluorfen and Bensulfuron (Oxyfluorfen 및 Bensulfuron 조합처리(組合處理)에 의한 벼 및 수종(數種) 잡초종간(雜草種間)의 선택반응상(選擇反應相)의 해부학적(解剖學的) 비교연구(比較硏究))

  • Guh, J.O.;Chon, S.U.;Han, S.U.;Kuk, Y.I.
    • Korean Journal of Weed Science
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    • v.12 no.2
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    • pp.132-143
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    • 1992
  • The study was conducted to find out synergistic effects by interaction on the basis on anatomical changes between paddy rice and weed species by mixture use of oxyfluorfen and bensulfuron at 0, $10^{-6}$ and $10^{-4}$M, respectively. Tissues were sampled at 72 hrs after soaking treatment and prepared for light microscopic examination and sectioned longitudinally and transversely stem into $8{\mu}m$ thick. As the results of microscopic examination, the major response of treated plant involved rupture and constrict in mesophyll cells and epidermal cells, and shrinks in bundle sheath cells by oxyfluorfen and disorganization and swelling in meristems by bensulfuron. Anatomical changes in rice was the least affected by even high concentration and two herbicide mixtures, whereas Echinochloa crus-galli was severely disorganized in meristem regions and ruptured in epidermal cells by mixture use. Monochoria vaginalis was completely ruptured by any treatment concentrations and mixtures. Scirpus juncoides was considerably tolerant to both herbicides and their mixture and was similar to those that occur in rice. Perennial weed, Sagittaria pigmaea was observed vacuolation, non-nucleation of cell, and irregular cell layering but in mixture injury was slight. Cyperus serotinus was severely shrunk and ruptured by mixture treatment. Eventually anatomical variations in all weed species was shown synergistic effect by use of herbicide mixtures.

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The Comparative Studies on Hatched Silkworm Dominance Seperation against Sex Seperation to meet Silk Promotion (잠견생산성 개선을 위한 의잠우열분리와 자웅분리의 비교연구)

  • Choe, Byong-Hee
    • Journal of Sericultural and Entomological Science
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    • v.15 no.2
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    • pp.21-28
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    • 1973
  • This report is prepared to promote cocoon natures for the use of silk reeling material. It is easily understandable that there must be disuniformity composed with superior group and inferior group in commercial silkworms. If such different groups be seperated by some method, it would be a great contribution for the cocoon production. For a comparative purpose, silkworm sex seperation carried out because male silkworms produce more silk than female worms. The author has developed a new chemical reagent available for the seperation of superior group and inferior group from commercial silkworms, which he has named it as Better Hybrid Controller (BHC). The obtained comparative results are summarized as followings. 1. Basic investigation of BHC application a) In case BHC applied with hybrid worms and pure line, the former one starts to adapt mulberry leaves earlyer than pure line variety. b) The mulberry adapting interval distribution of pure line worms after BHC application showed U type distribution, but hybrid worms showed L type or Poisson's distribution. c) In case of BHC application with silkworms, the longer period application is, the duller distribution was formed. d) When silkworms are seperated in two groups by use of BHC application, the earlyer mulberry adapted group is seemed as stronger than the other part and the group ratio is 2 : 1. 2. Comparation between sex seperation result and better hydrid control (BHC) seperation result. a) The cocoon shell per cent of male worm group showed betweer result than the female group but only 0.4% difference between sexes. b) The cocoon shell per cent of superior group, seperated by BHC, showed 0.7% more than the inferior group. c) The average cocoon shell per cent of BHC treated cocoons showed much more than the Control group as 1.6∼2.4% increase. Enven the inferior group showed better result than the Control. d) Such unexpected result is considered to be the result that BHC application is activating some thing with silkworm physiology. e) On the ether hand, the result of sexes seperated groups or male worm group did not show desirable conclusion as far as cocoon shell per cent is concerned. f) However, when the male group was reeled as silk, it showed much better silk yield or silk per cent of cocoon than the female group as much as one per cent difference between by sexes. Such result was brought by superior silk yield from cocoon shell as much as 87.4%. g) On the other hand, the male group showed lowest non breaking reelable ratio (63%) among all group comparation. h) When we compare cocoon qualities by sex seperation and BHC seperation against the Control, there is no qualitative change, but BHC group showed quantitative promotion with cocoon bave length as much as about hundred meters. i) In case of calculation for productive income of cocoon production, BHC applied group showed about ten per cent income promotion more than the Control. The sexes seperated group, however, showed rather negative result because the male cocoon produced poor weight per box eggs which could not cover it by the inclose of silk yield of it. j) So, the BHC application with the fetched worm stage brought about big promotion for cocoon production. k) BHC method may be used either for seperation purpose or quantitative promotion with whole silk-worms. 3. Only male silkworms rearing did not show desirable productivity, so there is no reason to work out it in the fetching stage of worm.

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Studies on electrophoretic pattern and amino acids of wild soybean protein[1] -Acrylamide gel electrophoretic pattern of seed protein- (야생대두단백질(野生大豆蛋白質)의 전기영동유형(電氣泳動類型)및 아미노산조성(酸組成)에 관(關)한 연구(硏究)[1] -종실단백질(種實蛋白質)의 Acrylamide gel 전기(電氣) 영동유형(泳動類型)-)

  • Park, H.;Lee, J.S.;Lee, C.Y.
    • Applied Biological Chemistry
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    • v.20 no.2
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    • pp.247-254
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    • 1977
  • Acrylamide gel electrophoretic pattern of 13 wild soybean (Glycine ussuriensis) was compared with that of G. gracilis and G. max var. Gwanggyo. Average Protein content (50%) of wild soybean was greater than that of C. gracilis (46%) and Gwanggyo (45%). Grain weight of wild soybean was one third of G. gracilis and one ninth of Gwanggyo. Electrophoresis of wild soybean protein showed total 16 different bands and three of which (Rm 0.09, 0.59 and 0.84) were specific and did not appeared in 86 var. of G. max which showed four specific bands (Rm 0.35, 0.45, 0.50 and 0.77) of total 17 bands. G. glacilis had all bands of Gwanggyo and two bands (Rm 0.53 and 0.59), one of which (Rm 0.59) was specific for wild soybean indicating that G. gracilis is middle type. Of 16 protein bands the third band (32%), the first band (28%) and the 5th band (13%) were main bands. Electrophoretic pattern could be sorted qualitatively into 4 groups, semiquantitatively into 6 groups and 2 or 4 groups depending on reference pattern by correlation or pattern similarity method. All sorting methods separated a wild soybean from Sogri mountain into a group and except that there were no similarity among methods but correlation methods seems more reasonable. Protein content was no relation with electrophoretic pattern but positively correlated with percent contribution of first band at 5% level suggesting that the first band may have a important role for protein synthesis.

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Korean athlete's recognition of sports dentistry and condition of teeth wear (한국 운동선수의 스포츠 치의학에 대한 인지도 및 치아교모상태에 관한 연구)

  • Lee, Sung-Bok;Choi, Dae-Gyun;Han, Kwang-Heung
    • Journal of Dental Rehabilitation and Applied Science
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    • v.18 no.4
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    • pp.235-249
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    • 2002
  • This study was accompolished to analyze and compare the number and area of the occlusal contact points in healthy volunteers and athletes with normal occlusion. Before the study, 89 athletes(sports career:8.6 years, average age 20) at Kyung Hee University were selected, and survey was accomplished for athlete's recognition about sports dentistry. For this study, 15 athletes(13 amles and 2 females with average age 20) and 21 healthy volunteers(14 mles and 7 females with average age 20.09) at Kyung Hee University were selected. The visual display acquired by scanning of occlusal record in maximal intercuspation was converted into 16 gray value image. Then, using computer program(J & Lee Occlusal Analyser), the pixel which was in definite range of the gray value was recognized, and the numbers of recognized pixel were calculated to area. The results were as follows : (1) On the survey about sports dentistry, 28% of 89 athletes didn't agree that human occlusion may be important, and 30% didn't have any idea of the influence of human occlusion during their sports activities. (2) The average numbers of total occlusal contact points were 31.05 in control group, and 34.67 in athlete group. The average area of total occlusal contacts was $100.25mm^2$ in control group, and $127.78mm^2$ in athlete group. (3) In control group, the average numbers of occlusal contact points were revealed in order as follows; the first molar(8.48), the second molar(8.24), the second premolar(4.71), the lateral incisor(2.90), the first premor(2.43), the central incisor(2.19), and the canine(2.1). The least average in canine(2.1) was similar to the average(2.19) in central incisor and (2.09) in lateral incisor. In athlete group, the average numbers of occlusal contact points were revealed in order as follows; the first molar(8.87), the second molar(8.47), the second premolar(5.60), the canine(3.80), the lateral incisor(3.33), the first premolar(2.67), and the central incisor(1.93). (4) In control group, the average areas of occlusal contact surface were revealed in order as follows; the first molar($39.47mm^3$), the second molar($37.54mm^3$), the second premolar($9.54mm^3$) the first premolar($6.18mm^3$), canine($3.49mm^3$), the central incisor($2.76mm^3$), and the lateral incisor($1.28mm^3$). In athlete group, the average areas of occlusal contact surface were revealed in order as follows; the first molar($44.11mm^3$), the second molar($40.69mm^3$), the second premolar($16.50mm^3$), the first premolar($9.39mm^3$), the canine($5.08mm^3$), the lateral incisor($3.7mm^3$), and the central incisor($2.25mm^3$). (5). With aging in both control and athlete group, there was a decreasing tendancy in average number of occlusal contact point, and was an increasing tendancy in average area of occlusal contact surface. In comparison at each age, both the numbers and area of occlusal contact were greater in athlete group than in control group. It was not significant in the numbers of occlusal contact points beween athlete and control group(p>0.1), but significant in the area of occlusal contact surface(p<0.05). (6) In comparision as to the kind of sports(Gymnastics:2, Rugby:3, Soccor:5, Ice hocky:5), the numbers of occlusal contact points were the most in ice hocky, and the area of occlusal contact surface was the greatest in gymnastics. With increasing a career in athlete group, there was a decreasing tendancy in average numbers of occlusal contact points, and was an increasing tendancy in average area of occlusal contact surface.

Electron Microscopic Studies on Olfactory Bulbs in the Vertebrates by Phylogenetics (계통발생에 따른 척추동물의 뇌후구에 대한 전자현미경적 연구)

  • Choi, W.B.;Chung, Y.H.;Seo, J.E.
    • Applied Microscopy
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    • v.15 no.2
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    • pp.31-68
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    • 1985
  • Authors are trying to unveil the ultrastructural organization of olfactory bulb, which has been summerized under light microscopic level or communicated only in some detail in different view point until now. For the critical point of view, since the phylogenetical approach will give the ultimate value in the correlative study between structural and functional bases (Brodal, 1969), the present study was carried out light and electron microscopic analyses of the structures of the neurons and synaptic organizations in olfactory bulbs from different animals in phylogenetical scale. We selected each one species from five animal classes: the house rabbit(Oryctolagus cuniculus var. domesticus [Gmelin]) from Mammalia, the domestic fowl (Gallus gallus domesticus Brisson) from Aves, the viper (Agkistrodon hylys [G.P. Pallas]) from Reptilia, a frog (Bombiana orientalis Boulenger) from Amphibia and the crussian carp (Carassius carassius [Linne]) from Pisces. For light microscopic study, samples were fixed in 10% formalin and paraffin sections were stained with hematoxylin-eosin. For the electron microscopic study, the tissues were fixed by perfusion through the heart or immersion with 1% paraform-aldehyde-glutaraldehyde mixture (phosphate buffer, pH 7.4), and final tissue block trimmed under dissecting microscope were osmicated (1% OsO4), they were embedded in Araldite or Epon 812, and ultrathin sections were made by LKB-V ultratome following the inspection of semi-thin sections stained with toluidine blue-borax solution. Ultra-thin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100CX electron microscope. We have summerized our morphological analyses as follows: 1. The olfactory bulb of rabbit, viper and frog shows the eight layers of fila olfactoria, glomerular, external granular, external plexiform, mitral cell, internal plexiform, internal granular, medullary but domestic fowl shows the five layers of glomerular, fibrillar, mitral, granular and medullary and the three layers of fibrilla, glomerular and medullary in crussian carp. The sharpness of demarcation between the layers shows deferential tendency according to phylogenetical order. 2. Mitral cells of vertebrate have large triangular or oval shape with spherical nuclei which contain not so much chromatin. The cytoplasm contains numerous cell organelles, of which Nissl's bodies or granular endoplasmic reticula arranged as parallel strands. Development of granular endoplasmic reticula were declined as the phylogentical grade is going lower. 3. Tufted cells of all animal are mostly spindle or polygonal contour and contain oval nuclei which located in periphery of cytoplasm. The nuclei of rabbit, fowl, viper and frog has relatively space chromatin, but a nucleus of crussian carp contain irregularly aggregated chromatin in karyoplasm. Their cytoplasmic volume and cell organelle contents are in between those of mitral cell and granular cell. They contain moderate amount of mitochondria, granular endoplasmic reticula, a few Golgi complex, polysomes, lysosome, etc. 4. Granule of cells of all the vertebrate amimals studied exhibit similar features; cells and their dense nuclei show spherical or oval contour, and they have the thin rim of cytoplasm which contain only a few cell organelles. 5. In rabbit, the soma of mitral cells were in contact with boutons with two types of synaptic vesicles, that is, round and flat vesicles, especially flat vesicles in boutons were showing reciprocal synapses. However, in domestic fowls, vipers, frogs and crussian carps, there were found boutons showing only spherical synaptic vesicles. 6. The boutons containing round synaptic vesicles were made contact with the some of tufted cell of olfactory bulb in the rabbits, fowls, vipers and frogs, but no synaptic boutons were observed in soma of tufted cells in crussian carps. In the frogs, there were observed dendrites were contact with the soma of tufted cells. 7. In the neuropils of plexiform, granular and glomerular layers olfactory bulbs in the vertebrate, the synapses were axo-large dendrites, axo-median and small dendrites, dendrodendritic, and axo-axonal contacts. However, in the neuropil of crussian carps, synapses were observed only in glomerular layer.

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Ecological Changes of Insect-damaged Pinus densiflora Stands in the Southern Temperate Forest Zone of Korea (I) (솔잎혹파리 피해적송림(被害赤松林)의 생태학적(生態学的) 연구(研究) (I))

  • Yim, Kyong Bin;Lee, Kyong Jae;Kim, Yong Shik
    • Journal of Korean Society of Forest Science
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    • v.52 no.1
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    • pp.58-71
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    • 1981
  • Thecodiplosis japonesis is sweeping the Pinus densiflora forests from south-west to north-east direction, destroying almost all the aged large trees as well as even the young ones. The front line of infestation is moving slowly but ceaselessly norhwards as a long bottle front. Estimation is that more than 40 percent of the area of P. densiflora forest has been damaged already, however some individuals could escapes from the damage and contribute to restore the site to the previous vegetation composition. When the stands were attacked by this insect, the drastic openings of the upper story of tree canopy formed by exclusively P. densiflora are usually resulted and some environmental factors such as light, temperature, litter accumulation, soil moisture and offers were naturally modified. With these changes after insect invasion, as the time passes, phytosociologic changes of the vegetation are gradually proceeding. If we select the forest according to four categories concerning the history of the insect outbreak, namely, non-attacked (healthy forest), recently damaged (the outbreak occured about 1-2 years ago), severely damaged (occured 5-6 years ago), damage prolonged (occured 10 years ago) and restored (occured about 20 years ago), any directional changes of vegetation composition could be traced these in line with four progressive stages. To elucidate these changes, three survey districts; (1) "Gongju" where the damage was severe and it was outbroken in 1977, (2) "Buyeo" where damage prolonged and (3) "Gochang" as restored, were set, (See Tab. 1). All these were located in the south temperate forest zone which was delimited mainly due to the temporature factor and generally accepted without any opposition at present. In view of temperature, the amount and distribution of precipitation and various soil factor, the overall homogeneity of environmental conditions between survey districts might be accepted. However this did not mean that small changes of edaphic and topographic conditions and microclimates can induce any alteration of vegetation patterns. Again four survey plots were set in each district and inter plot distance was 3 to 4 km. And again four subplots were set within a survey plot. The size of a subplot was $10m{\times}10m$ for woody vegetation and $5m{\times}5m$ for ground cover vegetation which was less than 2 m high. The nested quadrat method was adopted. In sampling survey plots, the followings were taken into account: (1) Natural growth having more than 80 percent of crown density of upper canopy and more than 5 hectares of area. (2) Was not affected by both natural and artificial disturbances such as fire and thinning operation for the past three decades. (3) Lower than 500 m of altitude (4) Less than 20 degrees of slope, and (5) Northerly sited aspect. An intensive vegetation survey was undertaken during the summer of 1980. The vegetation was devided into 3 categories for sampling; the upper layer (dominated mainly by the pine trees), the middle layer composed by oak species and other broad-leaved trees as well as the pine, and the ground layer or the lower layer (shrubby form of woody plants). In this study our survey was concentrated on woody species only. For the vegetation analysis, calculated were values of intensity, frequency, covers, relative importance, species diversity, dominance and similarity and dissimilasity index when importance values were calculated, different relative weights as score were arbitrarily given to each layer, i.e., 3 points for the upper layer, 2 for the middle layer and 1 for the ground layer. Then the formula becomes as follows; $$R.I.V.=\frac{3(IV\;upper\;L.)+2(IV.\;middle\;L.)+1(IV.\;ground\;L.)}{6}$$ The values of Similarity Index were calculated on the basis of the Relative Importance Value of trees (sum of relative density, frequency and cover). The formula used is; $$S.I.=\frac{2C}{S_1+S_2}{\times}100=\frac{2C}{100+100}{\times}100=C(%)$$ Where: C = The sum of the lower of the two quantitative values for species shared by the two communities. $S_1$ = The sum of all values for the first community. $S_2$ = The sum of all values for the second community. In Tab. 3, the species composition of each plot by layer and by district is presented. Without exception, the species formed the upper layer of stands was Pinus densiflora. As seen from the table, the relative cover (%), density (number of tree per $500m^2$), the range of height and diameter at brest height and cone bearing tendency were given. For the middle layer, Quercus spp. (Q. aliena, serrata, mongolica, accutissina and variabilis) and Pinus densiflora were dominating ones. Genus Rhodedendron and Lespedeza were abundant in ground vegetation, but some oaks were involved also. (1) Gongju district The total of woody species appeared in this district was 26 and relative importance value of Pinus densiflora for the upper layer was 79.1%, but in the middle layer, the R.I.V. for Quercus acctissima, Pinus densiflora, and Quercus aliena, were 22.8%, 18.7% and 10.0%, respectively, and in ground vegetation Q. mongolica 17.0%, Q. serrata 16.8% Corylus heterophylla 11.8%, and Q. dentata 11.3% in order. (2) Buyeo district. The number of species enumerated in this district was 36 and the R.I.V. of Pinus densiflora for the uppper layer was 100%. In the middle layer, the R.I.V. of Q. variabilis and Q. serrata were 8.6% and 8.5% respectively. In the ground vegetative 24 species were counted which had no more than 5% of R.I.V. The mean R.I.V. of P.densiflora ( totaling three layers ) and averaging four plots was 57.7% in contrast to 46.9% for Gongju district. (3) Gochang-district The total number of woody species was 23 and the mean R.I.V. of Pinus densiflora was 66.0% showing greater value than those for two former districts. The next high value was 6.5% for Q. serrata. As the time passes since insect outbreak, the mean R.I.V. of P. densiflora increased as the following order, 46.9%, 57.7% and 66%. This implies that P. densiflora was getting back to its original dominat state again. The pooled importance of Genus Quercus was decreasing with the increase of that for Pinus densiflora. This trend was contradict to the facts which were surveyed at Kyonggi-do area (the central temperate forest zone) reported previously (Yim et al, 1980). Among Genus Quercus, Quercus acutissina, warm-loving species, was more abundant in the southern temperature zone to which the present research is concerned than the central temperate zone. But vice-versa was true with Q. mongolica, a cold-loving one. The species which are not common between the present survey and the previous report are Corpinus cordata, Beltala davurica, Wisturia floribunda, Weigela subsessilis, Gleditsia japonica var. koraiensis, Acer pseudosieboldianum, Euonymus japonica var. macrophylla, Ribes mandshuricum, Pyrus calleryana var. faruiei, Tilia amurensis and Pyrus pyrifolia. In Figure 4 and Table 5, Maximum species diversity (maximum H'), Species diversity (H') and Eveness (J') were presented. The Similarity indices between districts were shown in Tab. 5. Seeing Fig. 6, showing two-dimensional ordination of polts on the basis of X and Y coordinates, Ai plots aggregate at the left site, Bi plots at lower site, and Ci plots at upper-right site. The increasing and decreasing patterns as to Relative Density and Relative Importance Value by genus or species were given in Fig. 7. Some of the patterns presented here are not consistent with the previously reported ones (Yim, et al, 1980). The present authors would like to attribute this fact that two distinct types of the insect attack, one is the short war type occuring in the south temperate forest zone, which means that insect attack went for a few years only, the other one is a long-drawn was type observed at the temperate forest zone in which the insect damage went on continuously for several years. These different behaviours of infestation might have resulted the different ways of vegetational change. Analysing the similarity indices between districts, the very convincing results come out that the value of dissimilarity index between A and B was 30%, 27% between B and C and 35% between A and C (Table 6). The range of similarity index was obtained from the calculation of every possible combinations of plots between two districts. Longer time isolation between communities has brought the higher value of dissimilarity index. The main components of ground vegetation, 10 to 20 years after insect outbreak, become to be consisted of mainly Genus Lespedeza and Rhododendron. Genus Quercus which relate to the top dorminant state for a while after insect attack was giving its place to Pinus densiflora. It was implied that, provided that the soil fertility, soil moisture and soil depth were good enough, Genus Quercuss had never been so easily taken ever by the resistant speeies like Pinus densiflora which forms the edaphic climax at vast areas of forest land. Usually they refer Quercus to the representative component of the undisturbed natural forest in the central part of this country.

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