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Life History and Systematic Studies of Pseudothrix borealis gen. et sp. nov. (=North Pacific Capsosiphon groenlandicus, Ulotrichaceae, Chlorophyta)

  • Hanic, Louis A.;Lindstrom, Sandra C.
    • ALGAE
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    • v.23 no.2
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    • pp.119-133
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    • 2008
  • We cultured a tubular marine green alga, originally identified as Capsosiphon groenlandicus (J. Agardh) K.L. Vinogradova, from Amaknak Island, Alaska. The alga had an alternation of heteromorphic generations in which tubular monoecious fronds produced quadriflagellate zoospores and/or biflagellate isogametes. The gametes fused to produce cysts or Codiolum-like zygotes with long, tortuous stalks. Cysts and codiola produced 8-16 aplanospores, which germinated in situ to yield upright fronds. Fronds arising from both aplanospores and zoospores displayed a distinctive development in which non-septate colorless rhizoids from the base of the initially uniseriate, Ulothrix-like filament were transformed into septate uniseriate Ulothrix-like photosynthetic filaments. These transformed filaments then developed new basal non-septate rhizoids. This pattern of rhizoids becoming filaments, which then produced new rhizoids, was repeated to yield a tuft of up to 50 fronds. Periclinal and longitudinal divisions occurred in each filament, starting basally, until the mature tubular thallus was achieved. Pyrenoid ultrastructure revealed several short inward extensions of chloroplast lamellae, each of which was surrounded by pyrenoglobuli. Analysis of ribosomal SSU and ITS sequences placed this alga in the family Ulotrichaceae, order Ulotrichales, together with but as a distinct species from North Atlantic Capsosiphon groenlandicus. Analysis of a partial ITS sequence from authentic Capsosiphon fulvescens, the current name of the type of the genus Capsosiphon, indicated that neither our material nor C. groenlandicus belongs in that genus, and we propose a new genus, Pseudothrix, to accommodate both species. We propose P. borealis for the North Pacific entity formerly called C. groenlandicus and make the new combination P. groenlandica for the Atlantic species.

Bisphenol A Disturbs Intracellular Calcium Homeostasis and its Relationship with Cytotoxicity (Bisphenol A에 의한 신경계 세포의 칼슘 항상성 교란 및 세포독성에 미치는 영향)

  • Lee Yoot Mo;Lee Sang Min;Son Dong Ju;Lee Sun Young;;Nam Sang Yun;Kim Dae Joong;Yun Young Won;Yoo Hwan Soo;Oh Ki Wan;Kim Tae Seong;Han Soon Young;Hong Jin Tae
    • Toxicological Research
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    • v.20 no.3
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    • pp.241-250
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    • 2004
  • We previously found that bisphenol A (BPA) caused neurotoxic behavioral alteration. Since disturbance of calcium homeostasis is an implicated contributor in the neurotoxic mechanism of environmental toxicants, we investigated whether BPA alters calcium homeostasis. Unlike other neurotoxic agents which cause increase of intracellular calcium level, BPA decreased $[Ca^{2+}]_i$ dose-dependently in PC12 cells and cortical neuronal cells regardless of the calcium existence in buffer. BPA at greater concentrations than 100 $\mu\textrm{M}$ reduced cell viability significantly in both types of cells. BPA also suppressed L-glutamate (L-type channel activator, 30 mM) and trifluoperazine (calmodulin antagonist, 30 $\mu\textrm{M}$)-induced increase of $[Ca^{2+}]_i$. BPA further lowered caffeine (RYR activator, 100 $\mu\textrm{M}$)-decreased $[Ca^{2+}]_i$, but did not alter dantrolene (RYR inhibitor, 100 $\mu\textrm{M}$), heparin (IP3 inhibitor, 200 units/ml) and xestospongin C (IP3 inhibitor, 5 $\mu\textrm{M}$)-decreased $[Ca^{2+}]_i$. Cell viability was not directly related to intracellular calcium change by bisphenol A that alternation of intracellular calcium may not be a direct causal factor of BPA-induced neuronal cell death.

Assessment of environmental effects in scour monitoring of a cable-stayed bridge simply based on pier vibration measurements

  • Wu, Wen-Hwa;Chen, Chien-Chou;Shi, Wei-Sheng;Huang, Chun-Ming
    • Smart Structures and Systems
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    • v.20 no.2
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    • pp.231-246
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    • 2017
  • A recent work by the authors has demonstrated the feasibility of scour evaluation for Kao-Ping-Hsi Cable-Stayed Bridge simply based on ambient vibration measurements. To further attain the goal of scour monitoring, a key challenge comes from the interference of several environmental factors that may also significantly alter the pier frequencies without the change of scour depth. Consequently, this study attempts to investigate the variation in certain modal frequencies of this bridge induced by several environmental factors. Four sets of pier vibration measurements were taken either during the season of plum rains, under regular summer days without rain, or in a period of typhoon. These signals are analyzed with the stochastic subspace identification and empirical mode decomposition techniques. The variations of the identified modal frequencies are then compared with those of the corresponding traffic load, air temperature, and water level. Comparison of the analyzed results elucidates that both the traffic load and the environmental temperature are negatively correlated with the bridge frequencies. However, the traffic load is clearly a more dominant factor to alternate the identified bridge deck frequency than the environmental temperature. The pier modes are also influenced by the passing traffic on the bridge deck, even though with a weaker correlation. In addition, the variation of air temperature follows a similar tendency as that of the passing traffic, but its effect on changing the bridge frequencies is obviously not as significant. As for the effect from the alternation of water level, it is observed that the frequency baselines of the pier modes may positively correlate with the water level during the seasons of plum rains and typhoon.

Mutation Analysis of IDH1/2 Genes in Unselected De novo Acute Myeloid Leukaemia Patients in India - Identification of A Novel IDH2 Mutation

  • Raveendran, Sureshkumar;Sarojam, Santhi;Vijay, Sangeetha;Geetha, Aswathy Chandran;Sreedharan, Jayadevan;Narayanan, Geetha;Sreedharan, Hariharan
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.9
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    • pp.4095-4101
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    • 2015
  • IDH1/2 mutations which result in alternation in DNA methylation pattern are one of the most common methylation associated mutations in Acute myeloid leukaemia. IDH1/2 mutations frequently associated with higher platelet level, normal cytogentics and NPM1 mutations. Here we analyzed IDH1/2 mutations in 200 newly diagnosed unselected Indian adult AML patients and investigated their correlation with clinical, cytogenetic parameters along with cooperating NPM1 mutation. We detected 5.5% and 4% mutations in IDH1/2 genes, respectively. Except IDH2 c.515_516GG>AA mutation, all the other identified mutations were reported mutations. Similar to reported c.515G>A mutation, the novel c.515_516GG>AA mutation replaces $172^{nd}$ arginine to lysine in the active site of the enzyme. Even though there was a preponderance of IDH1/2 mutations in NK-AML, cytogenetically abnormal patients also harboured IDH1/2 mutations. IDH1 mutations showed significant higher platelet count and NPM1 mutations. IDH2 mutated patients displayed infrequent NPM1 mutations and lower WBC count. All the NPM1 mutations in the IDH1/2 mutated cases showed type A mutation. The present data suggest that IDH1/2 mutations are associated with normal cytogenetics and type A NPM1 mutations in adult Indian AML patients.

A study on the System for the Mobile electronic account (모바일 기반의 디지털콘텐츠 사례 전자장부시스템에 관한 연구)

  • Song Eun-Jee
    • Journal of Digital Contents Society
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    • v.6 no.1
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    • pp.19-24
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    • 2005
  • Mobile service is able to offer the elastic service to anyone regardless of the place and the tin. With this characteristics, the ubiquitous service could be also provided even to the place which the access was limited with the existing line service, which could improve the mutual connection and could result in the service extension Mobile communication companies, which realized the limit of sale only by telephone conversation, have made an effort to develop wireless internet with concentration as its alternation. Especially concentrating their effort both to the development of distinctive and various contents and to tin development of system for mobile service such as the mobile banking, mobile game and etc., they have done their best to secure the number of the people using the wireless internet. This study is to propose the electronic account system based on the mobile as a case study of contents production for such a mobile service. This system has its advantage to perform the financial management immediately when the income and outcome happen without limitation of the time and space. The information could be stored, searched and modified by using of the mobile phone for this system was made up for the weak point of the financial management for wired internet.

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Morphology and Reproduction of Symphyocladia latiuscula (Harvey) Yamada (Rhodophyta, Rhodomelaceae) in Korea (한국산 홍조 참보라색우무(Symphyocladia latiuscula (Harvey) Yamada)의 형태와 생식)

  • 최도성
    • Journal of Plant Biology
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    • v.34 no.1
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    • pp.59-66
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    • 1991
  • The morphotaxonomic characters and life history of Symphyocladia latiuscula (Harvey) Yamada were investigated with field and laboratory culture materials. The species is well defined by a 5-15 cm hight, entirely corticated thallus and congenital fusion of 5-7 segments between main axis and laterals. Although all the reproductive structures are basically similar to those of other species of the genus, it is characteristic that the pinnulae are transformed into the flabellated tetrasporangial stichidia. Vegetative trichoblasts are known to be absent in the Pterosiphonieae, but their presence in S latiuscula does not accept its taxonomic position in that tribe. As a result, the occurrence of vegetative trichoblast is not useful for a taxonomic character to distinguish the tribes. The species shows a Polysiphonia-type life history involving a dimorphic alternation of gametophytes and sporophytes in culture and field. It grows below the middle intertidal zone in all the coasts of Korea throughout the year, although fertile plants are normally found during the summer months.months.

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Study on The Contact Metamorphism of Weolagsan Granite (월악산화강암(月岳山花崗岩)의 접촉변성(接觸變成)에 관(關)하여)

  • Lee, Dai Sung;Kang, Jun Nam
    • Economic and Environmental Geology
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    • v.11 no.4
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    • pp.169-182
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    • 1978
  • The Weolagsan area consists of four units; (1) Low grade meta-sediments of the upper members of Ogcheon age unknown group such as Changri (mainly black slate and phyllitic rock), Majeonri (mainly alternation of slate, limestone and chert) and Hwanggangri Formation (pebble bearing phyllitic sediments); (2) Samtaesan Formation of Chosun System of Ordovician; (3) So called meta-volcanics and (4) Weolagsan Granite and its associations which intruded above mentioned meta-sediments and meta-volcanics. This study was focused to know the Woelagsan granite and its metasomatic effects to the country rocks petrographically and petrochemically. According to the field survey, microscopic work and some chemical analysis, the granite is a "normal granite" based on the Streckeisen's classification and belongs to a mass of the Central-zone younger group in Ogcheon geosynclinal belt. The granite metasomatized the country rocks along its northern contact zone. Zone of calcareous and cherty rocks (Majeonri formation) was silicified partly and skarned locally at the contact with the granite. The chemical analysis of the zone show no difinite variations in contents of $SiO_2$ and CaO with the distance from the granite. It seems to be indicated that the silicification of this part was not so metasomatized by the granite body, but thermally affected as much as to be partially remelted in the specific parts of the formations. Meta-volcanic rock zone was slightly chloritized near contact with the granite. Limestone of Samtaesan Formation was silicified and skarned along the contact zone by the granite body. The chemical analysis of the zone show some noticiable changes in compositions of $SiO_2$ and CaO with distance from the granite boundary. It can be imagined that the silicification of this zone was metasomatically originated by Woelagsan Granite. According to chemical analysis on several trace elements, the ratio of Zn/Cr and Ni/Cr are relatively higher than that of Cu/Cr in the above mentioned silicified zones. Generally the variation of these metal elements in the zones tend to be regular with distance from the granite body.

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Synthesis of Columnar Na-P Zeolite by Hydrothermal Process from Natural Zeolite of Korea (천연 Zeollte로부터 열수합성에 의한 주상 Na-P Zeolite합성)

  • Zhang, Yong-Seon;Jung, Pil-Kyun;Kim, Sang-Hyo
    • Korean Journal of Soil Science and Fertilizer
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    • v.36 no.6
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    • pp.357-366
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    • 2003
  • This study was conducted to develop n convenient and efficient granular type absorbent with high CEC from powdery zeolite, which is a waste produced while crushing the natural zeolite of Korea to get a particular particle size. The change of mineralogical characteristics during hydrothermal alternation of natural zeolite to Na-P zeolite in alkaline solution at various reaction times was determined by X-ray diffraction (XRD), scanning electron microscopy (SEM), and total elemental analysis. The columnar aggregate of Na-P Zeolite was produced by calcinating the natural zeolite-charcoal extrudates of about 3 mm diameter. In 24 hours reaction, clinoptillonite, mordenite and feldspar in natural zeolite were disappeared by 3 N NaOH treatment, while Na-P Zeolite with spherical granular structure was newly detected by XRD. As increasing reaction time, Si/Al ratio in remaining solution was deceased. The CEC of the synthesized material increased more than 2 times compared with that of natural zeolite, although the diameter of Na-P zeolite were rather increased.

Pig Skin Gelatin Hydrolysates Attenuate Acetylcholine Esterase Activity and Scopolamine-induced Impairment of Memory and Learning Ability of Mice

  • Kim, Dongwook;Kim, Yuan H. Brad;Ham, Jun-Sang;Lee, Sung Ki;Jang, Aera
    • Food Science of Animal Resources
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    • v.40 no.2
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    • pp.183-196
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    • 2020
  • The protective effect of pig skin gelatin water extracts (PSW) and the low molecular weight hydrolysates of PSW generated via enzymatic hydrolysis with Flavourzyme® 1000L (LPSW) against scopolamine-induced impairment of cognitive function in mice was determined. Seventy male ICR mice weighing 20-25 g were randomly assigned to seven groups: Control (CON); scopolamine (SCO, 1 mg/kg B.W., intraperitoneally (i.p.); tetrahydroaminoacridine 10 [THA 10, tacrine; 10 mg/kg B.W. per oral (p.o.) with SCO (i.p.)]; PSW 10 (10 mg/kg B.W. (p.o.) with SCO (i.p.); PSW 40 (40 mg/kg B.W. (p.o.) with SCO (i.p.); LPSW 100 (100 mg/kg B.W. (p.o.) with SCO (i.p.); LPSW 400 (400 mg/kg B.W. (p.o.) with SCO (i.p.). All treatment groups, except CON, received scopolamine on the day of the experiment. The oxygen radical absorbance capacity of LPSW 400 at 1 mg/mL was 154.14 μM Trolox equivalent. Administration of PSW and LPSW for 15 weeks did not significantly affect on physical performance of mice. LPSW 400 significantly increased spontaneous alternation, reaching the level observed for THA and CON. The latency time of animals receiving LPSW 400 was higher than that of mice treated with SCO alone in the passive avoidance test, whereas it was shorter in the water maze test. LPSW 400 increased acetylcholine (ACh) content and decreased ACh esterase activity (p<0.05). LPSW 100 and LPSW 400 reduced monoamine oxidase-B activity. These results indicated that LPSW at 400 mg/kg B.W. is a potentially strong antioxidant and contains novel components for the functional food industry.

A Study on the effects of CSRR-metamaterial on Microstrip Comb-line Array Antennas (마이크로스트립 콤 어레이 안테나에서 CSRR-메타물질의 영향에 관한 연구)

  • Ki, Hyeon-Cheol
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.5
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    • pp.187-192
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    • 2017
  • We investigated the effects of the CSRR-metamaterial on microstrip comb-line array antennas. Microstrip comb-line array antennas was designed with 12 radiators, gain of 16.09dBi and bandwidth of 0.24GHz in the 24GHz ISM band. The designed antenna had radiation beam perpendicular to the antenna plane, co-polarization gain of 16.09dBi and cross-polarization gain of -10.86dBi. the CSRR-metamaterial increased largely the impedance bandwidth of the antenna from 0.24GHz to 3.6GHz. however as co-polarization gain became 10.08dBi and cross-polarization gain became 14.1dBi, co-polarization was mixed with cross-polarization. And the antenna gain lowered by 1.99dB. On the investigation of the dependence on the split-direction of the CSRR rings, it showed nearly the same characteristics for up-splitted ring used case and down-splitted ring used case. However in the case of arranging up-splitted ring and down-splitted ring in alternation, co-polarization gain decreased to -1.29dBi and cross-polarization gain increased to 13.9dBi, which meant the wave was transited to cross-polarization majority wave.