• Title/Summary/Keyword: Comparative morphology

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Comparative Analysis of Leptospira Isolated in Korea and Leptospira from ATCC (유행성 출혈형 폐염양 질환의 병원체에 관한 연구)

  • Kim, Joo-Deuk;Lee, Tae-Yoon;Lee, Won-Young;Lee, Bong-Ki
    • The Journal of the Korean Society for Microbiology
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    • v.21 no.2
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    • pp.191-204
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    • 1986
  • Leptospira isolated from the patients with so called epidemic pulmonary hemorrhagic fever were comparatively studied with standard strains obtained from ATCC. The specific aim of this study was to clarify the morphologic heterogeneity of the isolates, i. e., coexistence of spiral forms in both handness, right and left, rod and spherical forms in their population by comparing them with those of the ATCC strains. No differences between our strains and ATCC strains were noticed in their growth characteristics, responses to the culture media, temperature, antibiotics and antifungal agents. Furthermore, the morphologic heterogeneity had been repeatedly observed even in cultures of standard ATCC strains, which had been noticed in the cultures of bacteria isolated in this laboratory. The serologic analysis of our isolates demonstrated that the bacteria reacted with L. icterohaemorrhagiae and L. australis regardless their differences in time of isolation(1984, 1985). Thus, it was concluded that the spiral bacteria isolated in this laboratory are Leptospira of a new serovar which still remained to be determined. And the previous reports on the morphology of the Leptospira, which described that the Leprospira population has only spiral forms with right. handed coils might be reconsidered.

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Ultrastructural Study of Drosophila Ocellar Visual System by Osmium Impregnation (오스뮴침착법에 의한 초파리 단안시각계의 미세구조)

  • Yoon, Chun-Sik
    • Applied Microscopy
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    • v.29 no.4
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    • pp.451-457
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    • 1999
  • Ultrastructure of adult Drosophila ocellus was compared with conventional electron microscopic method and osmium impregnation. When osmium impregnation was applied, some organelles of cells were strongly stained. Especially, subrhabdomeric cisternae (SRC) were strongly stained and showed network-iike structure as in compound eye. Other organelles including SSC, ER, nuclear envelope, pigment granules and mitochondria were also strongly stained. These organelles are known as a general calcium ion reservoir. In conclusion, the strong effect of light and shade by osmium impregnation was regarded as a result of strong binding between calcium ion and osmium tetroxide. Thus, we agree to the opinion that osmium impregnation is very useful methods to the comparative morphology of cell organelles.

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A comparative study on mechanical properties of TiN and TiAlN films prepared by Arc Ion Plating Technique (아크 이온 플레이팅법에 의해 증착된 TiN과 TiAlN 박막의 기계적 특성 비교)

  • 윤석영;이윤복;김광호
    • Journal of the Korean institute of surface engineering
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    • v.35 no.4
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    • pp.199-205
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    • 2002
  • TiN and TiAlN films were deposited on SKD 11 steel substrates by an arc ion plating (AIP) technique. The crystallinity and morphology for the deposited films were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The mechanical properties of both films were investigated through the indentation, impact, and wear test. Those films fairly adherent to SKD 11 steel substrate, showed hardness values of 2300 $\pm$ 100kg/$\textrm{mm}^2$ and 3200 $\pm$ 100kg/$\textrm{mm}^2$ with a load of 25g, respectively. During impact test, TiAlN films showed much superior impact wear resistance to TiN films. It could be suggested that the TiN films was failed relatively by plastic deformation with oxidation during impact test, while TiAlN films was failed by brittle fracture and resisted the oxidation by the impact energy. The friction coefficient of TiAlN films became lower than that of TiN films at high sliding speed condition although it was higher than that of TiN films at low speed. Therefore, TiAlN films was suggested to be more advantageous than TiN films for high speed machining fields.

Iron-loaded Natural Clay as Heterogeneous Catalyst for Fenton-like Discoloration of Dyeing Wastewater

  • Xu, Huan-Yan;Ha, Xiu-Lan;Wu, Ze;Shan, Lian-Wei;Zhang, Wei-Dong
    • Bulletin of the Korean Chemical Society
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    • v.30 no.10
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    • pp.2249-2252
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    • 2009
  • The clay-based Fe-bearing catalyst was successfully prepared through ion-exchange reaction and applied as heterogeneous catalyst for discoloration of acid fuchsine (AF) in an aqueous solution by Fenton-like reaction. Experimental results demonstrated that the AF discoloration ratios increased by increasing Fe-loaded clay dosage and initial $H_2O_2$ concentration, and by decreasing the pH, respectively. The lower the initial AF concentration, the shorter the reaction time needed to achieve complete discoloration of AF. Comparative studies indicated that AF discoloration ratios were much higher in presence of Fe-loaded clay and $H_2O_2$ than those in presence of $H_2O_2$, raw natural clay or Fe-loaded clay only and raw natural clay and $H_2O_2$ jointly. After AF discoloration, there existed no new phases in the clay samples detected by XRD and no change in the clay crystal morphology observed by SEM. A mechanism proposed suggested adsorption and Fenton-like reaction were responsible for discoloration of AF.

Comparative Anatomy of the Korean Native Goat 2. Mesenteric mast cell (한국 재래 산양의 비교해부학적 연구 2. 장간막 비만세포에 대하여)

  • Lee, Heung Shik;Kim, Chang Ki
    • Korean Journal of Veterinary Research
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    • v.14 no.2
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    • pp.151-157
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    • 1974
  • This study was carried out to investigate on the morphology, distribution and stainability of the mast cells in the Korean Native goat. For the study, the experimental animals were anesthetized with pentobarbital sodium and opened the anterior abdomianl wall to remove immediately the specimens with a minimum of mechanical effects. The mesenteries were fixed in 10% neutral formalin, 4% basic lead acetate, absolute alcohol and ethlene glycol monoethyl ether. Following 24 hours of fixation, the toto preparation stained with 0.4% toluidine blue, 1% methylene blue, 1.5% bismark brown, saturated thionine and thionlne-methylene blue complex solution. The preparation were observed from 10 microscopic field with 450 magnification. The results were as follows: 1. The form of the mesenteric mast cell was found 2 types. One was spindle form in larger number around vessels, the other was ovoid or spherical form in connective tissue far from blood vessels. 2. The average size was $18.63{\pm}5.75{\mu}m$ in length, $10.61{\pm}3.39{\mu}m$ in width and number was $105.50{\pm}18.45$. 3. Ethylene glycol monoethyl ether was particularly useful in preserving the mast cell granules. 4. Thione-methylene blue complex solution might be recommended to stain of granules.

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Plantlet Growth, and Leaf and Stomatal Characteristics of Alocasia amazonicaas Affected by Medium Supply Methods in Bioreactor Culture (Alocasia amazonica의 생물반응기 배양에서 배지 공급 방식이 식물체의 생장과 잎조직 및 기공의 특성에 미치는 영향)

  • Cho, Eun-A;Hahn, Eun-Joo;Paek, Kee-Yoeup
    • Journal of Plant Biotechnology
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    • v.33 no.2
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    • pp.117-122
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    • 2006
  • Comparative studies on medium supply in bioreactors (raft, immersion and ebb and flood) have revealed that multiplication and growth of Alocasia Amazonica were greatest in the raft system, while lowest in ebb and flood system. In the raft system, the basal part of the shoots was continuously in contact with medium, which enabled a constant uptake of nutrients as well as aeration to the explants. The number and the size of leaf stomata were higher in the raft system compared with immersion and ebb&flood system. In the immersion system, plantlets were deformed and epidermal cells in leaves were irregular with a large intercellular space. The results suggested that the medium supply should be controlled properly to maintain normal and healthy plantlets during liquid cultures in bioreactors Which affects morphology and physiology Of the plantlets.

Study on chromosomes survey of Korea native dogs (국내 토종개의 염색체 조사에 관한 연구)

  • Park, Chang-Eun
    • Korean Journal of Veterinary Service
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    • v.34 no.3
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    • pp.291-296
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    • 2011
  • The karyotype of the domestic dog is widely accepted as one of the difficult mammalian karyotypes to work. In contrast to many other animals, knowledge about the canine karyotype is quite sparse. The dog has a total of 78 chromosomes; all 76 autosomes are acrocentric in morphology and show only a gradual decrease in length. But appear to be quite small and difficult to identify unambiguously. To purchased standardization of chromosome in Korea native dog, there were analyzed by conventional trypsin/Giemsa staining (GTG-banding techniques), and were compared with 4, 6, 8, 11, 13, 17 chromosome. There were no variations in karyotypes which were analyzed by conventional GTG-banding techniques, but differences were observed in G-banding patterns with Sapsaree, Jindo, Gyeongju DongGyeong dogs, Welshi-Corgi. It is not clear that these disagreements in G-banding patterns between strains of dog were caused by chromosome polymorphism or a difference in interpretation. Comparative analysis of the distribution patterns of conserved segments defined by dog paints in the genomes of the Korea native dogs demonstrates that their differences in the karyotypes of these three species could have resulted from acrocentric banding patterns.

A comparative study on cooking qualities of imported and domestic rices(Chuchung byeo) (수입 쌀과 국산 쌀(추청벼)의 취반 특성 비교)

  • 한승희;최은정;오명숙
    • Korean journal of food and cookery science
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    • v.16 no.1
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    • pp.91-97
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    • 2000
  • The cooking properties of imported rice (Thai and Chinese rice, harvested in 1998) were compared with those of domestic rice(Chuchung byeo, harvested in 1998 and 1997). The morphology, general composition, color value, RVA viscosities, cooking properties, texture and sensory properties of raw or cooked rice were measured. Thai rice showed lower water absorption rate than others, however its amylose content and gelatinization temperature were higher. While the cooked Thai rice showed the least preference due to its hard and nonsticky properties, Korean rice harvested in 1998 showed the greatest cooking quality in stickiness and softness. Although Chinese rice was inferior to Korean rice harvested in 1998, there were no significant difference between Chinese rice harvested in 1998 and Korean rice harvested in 1997.

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Comparative Ultrastructures of the Fertilized Egg Envelopes in Nothobranchius guentheri and Nothobranchius patrizii, Nothobranchiidae, Teleostei

  • Kwon, Jung Kyon;Jung, Han Suk;Kim, Dong Heui
    • Applied Microscopy
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    • v.45 no.3
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    • pp.144-149
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    • 2015
  • Nothobranchius guentheri and Nothobranchius patrizii have special life cycle to sustain the dry season. So, we investigated the fertilized eggs morphology, and compared ultrastructures of surface structures and the cross section of fertilized egg envelopes using light and electron microscopes to determine whether these fertilized eggs and egg envelopes show the species specificity or have special structure to sustain the dry season. These fertilized eggs were spherical, yellowish, demersal and adhesive, and had a one-sided large oil droplet. The whip-like structures, adhesive filament were distributed throughout egg envelope in both species. But, that of N. guentheri was covered with fibrous structures, and that of N. patrizii was smooth. The egg envelope consisted of two distinct layers: an outer, electron-dense layer containing adhesive filaments and an inner layer of 16 to 17 horizontal electron-dense lamellae alternating with 15 to 16 interlamellae of lower electron density in both species. The external shapes of fertilized egg and section of fertilized egg envelope were same, but ultrastructure of adhesive filaments on the outer surface was concluded to show species specificity. Our data indicate that the ultrastructural differences of adhesive filament and outer surface of fertilized egg envelope show species specificity although these species belong to same genus.

The Characterization of Crosslinked SPEEK Based Ion Exchange Membranes Prepared by EB Irradiation Method (전자선을 이용해 가교된 SPEEK 기본 물질로 하는 이온 교환막의 특성 분석)

  • Song, Ju-Myung;Shin, Junhwa;Sohn, Joon-Yong;Nho, Young-Chang
    • Journal of Radiation Industry
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    • v.5 no.2
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    • pp.151-157
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    • 2011
  • Crosslinked SPEEK/PVDF membrane were prepared by EB radiation method with various contents of PVDF. The prepared membranes were subjected to a comparative study of proton exchange membranes for fuel cell appreciations. The crosslinked SPEEK/PVDF membranes were characterized by using DMA, DSC and SAXS. The DMA data indicate that the ionic modulus values and cluster $T_g$ decrease with increasing PVDF content. Thus, it was suggested that the number of clustering in the crosslinked membranes can be reduced with increasing PVDF content. The DSC results were shown that the degree of crystalline of the membrane increased with increasing PVDF content. The morphology of the crosslinkied membranes was shown that with increasing PVDF content, the number of crystalline domain of the SPEEK/PVDF membranes increased but ionic aggregation of the membranes decreased. The water uptake behavior, ionic exchange capacity (IEC) and proton conductivity were decreased with increasing PVDF content. The overall findings suggest that the crosslinked membranes offer the possibility for improving the performance of PEMFC, provided that the membranes have thermal and hydration stability.