• Title/Summary/Keyword: Morphological part

Search Result 537, Processing Time 0.197 seconds

Morphological Identification and Phylogenetic Analysis of Laelapin Mite Species (Acari: Mesostigmata: Laelapidae) from China

  • Yang, Huijuan;Yang, Zhihua;Dong, Wenge
    • Parasites, Hosts and Diseases
    • /
    • v.60 no.4
    • /
    • pp.273-279
    • /
    • 2022
  • Laelapinae mites are involved in transmission of microbial diseases between wildlife and humans, with an impact on public health. In this study, 5 mite members in the subfamily Laelapinae (laelapin mites; LM) were morphologically identified by light microscopy, and the phylogenetic relationship of LM was analyzed in combination with the sequence information of part of the LM cytochrome oxidase subunit I (cox1) gene. The morphological identification revealed that 5 mites belonged to the genera Laelaps and Haemolaelaps, respectively. Sequence analysis showed that the ratio of nonsynonymous mutation rate to synonymous mutation rate of LM was less than 1, indicating that the LM cox1 gene had undergone purifying selection. Phylogenetic analysis showed that the Laelapinae is a monophyletic group. The genera Haemolaelaps and Hyperlaelaps did not separated into distinct clades but clustered together with species of the genus Laelaps. Our morphological and molecular analyses to describe the phylogenetic relationships among different genera and species of Laelapinae provide a reference for the improvement and revision of the LM taxonomy system.

Korean Part-of-Speech Tagging System Using Resolution Rules for Individual Ambiguous Word (어절별 중의성 해소 규칙을 이용한 혼합형 한국어 품사 태깅 시스템)

  • Park, Hee-Geun;Ahn, Young-Min;Seo, Young-Hoon
    • Journal of KIISE:Computing Practices and Letters
    • /
    • v.13 no.6
    • /
    • pp.427-431
    • /
    • 2007
  • In this paper we describe a Korean part-of-speech tagging approach using resolution rules for individual ambiguous word and statistical information. Our tagging approach resolves lexical ambiguities by common rules, rules for individual ambiguous word, and statistical approach. Common rules are ones for idioms and phrases of common use including phrases composed of main and auxiliary verbs. We built resolution rules for each word which has several distinct morphological analysis results to enhance tagging accuracy. Each rule may have morphemes, morphological tags, and/or word senses of not only an ambiguous word itself but also words around it. Statistical approach based on HMM is then applied for ambiguous words which are not resolved by rules. Experiment shows that the part-of-speech tagging approach has high accuracy and broad coverage.

External Morphological Development of Post-larvae and Juveniles of Red Seabream, Pagrus major

  • Park, Jae-Min;Han, Kyeong-Ho;Kang, Seung-Wan;Lee, Jeong-Tae
    • Development and Reproduction
    • /
    • v.21 no.1
    • /
    • pp.63-69
    • /
    • 2017
  • On the 15 days after hatching, the larvae was 4.24-5.10 mm (mean $4.66{\pm}2.18mm$) in total length, and the fins of the membrane started to develop into a fan shape and the melanophore was deposited upper the alimentary canal of the abdomen and on the bladder. At 35 days after hatching, the post-larvae formed a branch-shaped melanophore on the head part with a total length of 6.98-12.5 (mean $9.35{\pm}1.71$) mm, formed on the upper and lower parts of the caudal part, formed on the upper and lower parts of the caudal part, and deposited under the head part and abdomen. At 40 days after hatching, the juvenile was 11.3-18.1 (mean $14.9{\pm}1.53$) mm in total length.

New record of a sea star of genus Solaster (Asteroidea: Valvatida: Solasteridae) from the East Sea, Korea

  • Ubagan, Michael Dadole;Shin, Sook
    • Korean Journal of Environmental Biology
    • /
    • v.37 no.4
    • /
    • pp.503-507
    • /
    • 2019
  • Asteroid specimens were collected using fishing nets from the East Sea, Korea. The specimens were identified as Solaster paxillatus Sladen, 1889, belonging to the family Solasteridae of the order Valvatida. This species can be distinguished from three other Korean Solaster species by having 10 arms; subambulacral spines comprising four or five near base of arm, six or seven in middle part, and five or six in distal part of arm; furrow spines comprising four or five near basal part and three or four in distal part of arm; and suboral spines comprising more than ten spinules. The morphological characteristics of this species were described with illustrations. Solaster paxillatus is first reported in marine fauna of Korea.

A Taxonomic Study on Korean Allium L. Based on the Morphological Characters (형태학적 형질에 기초한 한국산 부추속의 분류학적 연구)

  • Choi, Hyeok-Jae;Jang, Chang-Gee;Lee, You-mi;Oh, Byoung-Un
    • Korean Journal of Plant Taxonomy
    • /
    • v.37 no.3
    • /
    • pp.275-308
    • /
    • 2007
  • For 20 taxa of Korean Allium, including 16 species and 5 varieties, examined were morphological characters (i.e. sexuality, structure and shape of underground part, types and growing patterns of leaf and scape, and shapes of perianth, filament and pistil). The specialization and the evolutionary trends of taxonomic characters were inferred from morphological examination. Taxonomic relationships and system of Korean Allium were also studied. The characters showing evolutionary trends were the structure and shape of underground part including rhizome and bulb, leaf, scape, inflorescens, filament and ovary. It seemed that thin and short rhizome developed from thick and long one, and the membranous simple bulb tunic evolved into fibrous reticulate one. The presence of hyaline sheath in A. monanthum of sect. Microscordum was apomorphic. Both angular leaf blade with 2-rowed vascular bundle and flat blade with 1-rowed vascular bundle were developed from terete one with 2-rowed vascular bundle. The base of filament have differentiated from entire to toothed, and 2-ovuled ovary as well as erect scape before flowering was plesiomorphic type. In addition, sexuality, structure of underground part, the presence of hyaline sheath and cross-section structure of leaf were taxonomic characters with the level of the subgenus in this genus. Shape of rhizome, bulb, leaf, scape and pedicel discriminated each section from other ones in the subgenera easily. The shape and arrangement of perianth and filaments were the diagnostic characters for species level along with shape of ovary and stigma.

Morphological Study on the Leaf Nectar Glands of Some Prunus Species in Korea (한국산(韓國産) Prunus속(屬) 수(數) 종(種)의 엽밀선(葉蜜腺)의 형태(形態)에 관한 연구(硏究))

  • Park, Kwang Woo;Chong, Woo Hong
    • Journal of Korean Society of Forest Science
    • /
    • v.79 no.4
    • /
    • pp.407-412
    • /
    • 1990
  • Morphological characters on the leaf nectar gland of Korean Prunus 4 species and 1 form were observed by SM. The results were summarized as follows ; The shapes of nectar gland on the plane figure were two, the circular and the irregular ovate. The species of circular shape were P. maackii, P. maximowiczii, P. sargentii and P. yedoensis. The irregular ovate shape was only one species, P. pendula for. ascendens. The shapes of nectar gland on the side figure were the reentrant apices and the rounded. The reentrant apices were two shapes. First, the species of the center reentrant was three, P. maackii, P. sargentii and P. yedoensis. Second, the species of the irregular reentrant was P. pendula for. ascendens. The rounded apex was only one species, P. maximowiczii. Especially on the P. pendula for. ascendens, the upheaval situation on surface of leaf blade was due to the sinking of reverse part of leaf blade at the nectar gland. The point of this abnormal shape was well distinguished from the other species. On the frequency by the part of leaf with nectar gland, the species to be observed only at the leaf base was P. pendula for. ascendens, the other species was observed two part of leaf base and petioles. In this study, some Prunus species were well keyed out on the basis of the morphological characters of leaf nectar gland.

  • PDF

Investigation on glass transition temperature of low density polyethylene by the characteristics of temperature dependent linear expansion (선팽창 온도특성에 의한 저밀도 폴리에틸렌의 유리 천이온도에 대한 고찰)

  • 김봉흡;강도열;김재환
    • 전기의세계
    • /
    • v.30 no.7
    • /
    • pp.441-447
    • /
    • 1981
  • As a preceeding work for the study on dielectric characterstics of a kind of low density polyethylene introduced morphological change by mechanical method, glass transition temperature which is regarded as a macroscopic aspect for relaxation of molecular chain segments has been observed by means of temperature dependent dilatometric measurement. The origina specimen clearly shows two knees which correspond to two peaks (.gamma. and .betha. peak) in the intenal friction measurement, suggesting the existence of separated glass transition temperatures at 150.deg.k and 260.deg.k respectively. On the specimen irradiated to 100 Mrad both glass transition temperatures tend to shift towards high temperature sides because of crosslinking by irradiation. furthemore an evidence can be seen that radiation effect, even in amorphous phase, is also slelctive depending on slight morphological differences. The specimen extended to four times in length shows a peculiar nature such as negative linear thermal expansion coefficient increasing with temperature between 220.deg.k and ambient temperature and that this fact is interpreted by considering that c axis of the lattice aligns along the extended direction by drawing, further c axis inherently possesses the characteristics of negative linear thermal expansion coefficient. For the observations that the relatively small positive linear expansion on the specimen extended to ca. two times as well as the part below 220.deg.k of the specimen extended to four times, it is considered for the reason of the facts that the incompletely oriented region indicated as the middle part of Peterlin's model tends to restore partially to orginal arrangement-a kind of phase transition-as increasing with temperature.

  • PDF

Antiapoptotic Role of Pyruvate in Vascular Endothelial Cells (혈관내피세포의 Apoptosis에 대한 Pyruvate의 억제효과)

  • 정세진
    • Journal of Nutrition and Health
    • /
    • v.32 no.3
    • /
    • pp.318-326
    • /
    • 1999
  • Apoptotic cell death, characterized by DNA fragmentation and morphological changes, has previously been shown to occur in vascular endothelial cells cultured with hydrogen peroxide. The present study examined the induction of apoptosis by hydrogen peroxide and whether pyruvate, a key glycolytic intermediate and $\alpha$-keto-monocarboxylate, can inhibit the apoptotic effects in bovine pulmonary artery endothelial cells(BPAECs). Culture with 500uM hydrogen peroxide resulted in 30% cell death and induced morphological changes and DNA fragmentation. Cell injury was inhibited by the treatment with pyruvate. Pyruvate(0.1-5.0mM), and cell viability increased in a dose-dependent manner. In the presence of pyruvate(10~20mM), the viability was improved to over 95%. In contrast, treatment with lactate, a reduced form of phyuvate, did not protect against cell death oxidative stress-induced loss of viability and apoptosis was examined with $\alpha$-cyano-3-hydroxycinnarmate(COHC) as a selective mitochondrial monocarboxylate transport blocker. Incubation with COHC(500uM) did not significantly affect cell viability in the presence of hydrogen peroxide. The cytoprotection by pyruvate(3mM)against hydrogen peroxide stress was abolished by COHC. This indicates that the cytoprotection by pyruvate against oxidative stress in endothelial cells is mediated, at least in part, by mitochondrial pyruvate uptake and hence endothelial enerygetics. However, cytosolic mechanisms related, at least in part, by mitochondrial pyruvate uptake and hence endothelial energetics. However, cytosolic mechanisms related to the glutathione system may also contribute. The results suggest that pyruvate has therapeutic potential in the treatment of oxidative stress-induced cytotoxicity associated with increased apoptosis.

  • PDF

Morphological Parameters of the Sludge Flocs in a Long Rectangular Secondary Settling Tank (장방형 침전지에서 길이에 따른 슬러지 floc의 형태에 관한 연구)

  • Kim, Youngchul;Lee, Jin-Woo;Kang, Min-Gi
    • Journal of Korean Society on Water Environment
    • /
    • v.22 no.3
    • /
    • pp.468-474
    • /
    • 2006
  • In the secondary settling tanks, three different types of settling phenomena occurs; i.e., zone settling for sludge thickening in the bottom part of settling tank, and discrete and flocculent settling for clarification in the upper part. In this paper, morphological parameters of the floc in sludge blanket layers along the length of a long rectangular tank were investigated. The plant used for this study had a serious bulking problem caused by Microthrix parvicella. Floc size decreased as the surface area of settling tank increases, which indicates that in the secondary settling tank where zone settling believed to be predominant, free or flocculent type of settling contributes to floc size distributions. Large floc particles deposit in the front zone of settling tank, but small and loose flocs mostly in the zone near its outlet. On the other hand, filament length contained in one gram of sludge blanket solid increases along the flow direction. Large flocs with less filaments settle faster, but small flocs having more filaments result in poor settling. These results support function of microorganism selection occurring in secondary settling tank. In addition, designing a long rectangluar settling tank with double hoppers might be one of the ways of bulking control, but this idea has to be verified with a further study.

Morphological Development and Reproductive Behavior of Hedgehog Seahorse Hippocampus spinosissimus (Teleostei: Syngnathidae) (Hedgehog Seahorse (Hippocampus spinosissimus)의 산출습성 및 형태발달)

  • KANG Su Youn;KOH Jeong Rack;JEONG Seung Beom;KIM Suam
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.38 no.5
    • /
    • pp.298-303
    • /
    • 2005
  • This study described the reproductive behavior and the morphological development of the larvae and juvenile of the hedgehog seahorse (Hippocampus spinosissimus). Larvae released from male seahorse were reared for 30 days in the laboratory. At the birth, the small flap-like mouth and anus of the yolk-sac larvae were open, and the yolk was completely absorbed within 1 day. The size of newborn larvae ranged 7.01-13.19mm (mean $9.26\pm1.9mm$, n=9) in TL (total length). The larvae had 15-16 pectoral fin rays and 19 dorsal fin rays, but 4 anal fin rays were not completely developed. The larval size ranged 13.38-14.38 mm (mean $13.96\pm0.3mm$, n=6) in TL at 1 day after release, and they had 17 pectoral fin rays, 20 dorsal fin rays and 4 anal fin rays when the larvae reached the juvenile stage. Juvenile size ranged 14.98-16.42mm (mean $15.84\pm0.5mm$, n=5) in TL at 3 days after release, and 1, 4, 6, 8 trunk spines extended quickly. Terminal part of the coronet became a four-forked wedge shape concurrently. Juvenile became 23.25mm (n=l) in TL after 15 days and all 11 trunk rings was connected completely. After 20 days, the juveniles were 24.66-28.65mm (mean $27.26\pm1.6mm$, n=5) in TL, and many melanophores appeared in integument. In the eye lenses, 5-6 lusters were formed. After 30 days, the juveniles were 26.78-28.26 mm (mean $27.36\pm0mm$, n=4)in TL and 8-9 lusters appeared on the eye lenses. Coronet terminal part developed to a five-forked crown-shape completely.