• Title/Summary/Keyword: One new species

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A new record of Plaintive Cuckoo (Cacomantis merulinus) in Korea (우는뻐꾸기(가칭: Cacomantis merulinus)의 국내 첫 기록)

  • Kim, Hankyu;Kim, Hwa-Jung;Park, Jin-young
    • Korean Journal of Ornithology
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    • v.25 no.2
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    • pp.133-135
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    • 2018
  • Plaintive Cuckoo (Cacomantis merulinus) is a small cuckoo species in Family Cuculidae that is mainly distributed in the Oriental Region. On May 1. 2016, one juvenile Plaintive Cuckoo was found at Somaemuldo Island, Korea ($34^{\circ}37^{\prime}38.73^{{\prime}{\prime}}N$ $128^{\circ}33^{\prime}0.44^{{\prime}{\prime}}E$). The bird was identified as C. merulinus by its morphological traits, especially primary projection, the shape of bars on tertials, and pale supercilium. These characteristics were distinctive from other similar small cuckoos in genus Cacomantis and Cuculus, during the field observation and examination of photographs. This record is the first of this species in Korea, and the northernmost record of this species.

DEVELOPMENT OF A NEW ION TRANSPORT CODE FOR PLANETARY IONOSPHERES WITH EXPLICIT TREATMENT OF ION-ION COLLISION

  • KIM YONG HA
    • Journal of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.59-66
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    • 2005
  • A new ion transport code for planetary ionospheric studies has been developed with consideration of velocity differences among ion species involving ion-ion collision. Most of previous planetary ionosphere models assumed that ions diffuse through non-moving ion and neutral background in order to consolidate continuity and momentum equations for ions into a simple set of diffusion equations. The simplification may result in unreliable density profiles of ions at high altitudes where ion velocities are fast and their velocity differences are significant enough to cause inaccuracy when computing ion-ion collision. A new code solves explicitly one-dimensional continuity and momentum equations for ion densities and velocities by utilizing divided Jacobian matrices in matrix inversion necessary to the Newton iteration procedure. The code has been applied to Martian nightside ionosphere models, as an example computation. The computed density profiles of $O^+,\;OH^+$, and $HCO^+$ differ by more than a factor of 2 at altitudes higher than 200 km from a simple diffusion model, whereas the density profile of the dominant ion, $O_2^+$, changes little. Especially, the density profile of $HCO^+$ is reduced by a factor of about 10 and its peak altitude is lowered by about 40 km relative to a simple diffusion model in which $HCO^+$ ions are assumed to diffuse through non-moving ion background, $O_2^+$. The computed effects of the new code on the Martian nightside models are explained readily in terms of ion velocities that were solved together with ion densities, which were not available from diffusion models. The new code should thus be expected as a significantly improved tool for planetary ionosphere modelling.

Neuroprotective Effect of the Water-insoluble fraction of Root Barks of Dictamnus dasycarpus 70% Ethanolic Extract on Glutamate-Induced Oxidative Damage in Mouse Hippocampal HT22 Cells (백선피 70% 에탄올 추출물의 비수용성 분획물의 뇌세포 보호 효과)

  • Choi, Hyun-Gyu;Lee, Dong-Sung;Li, Bin;Jun, Ki-Yong;Jeong, Gil-Saeng;Kim, Youn-Chul
    • Korean Journal of Pharmacognosy
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    • v.42 no.2
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    • pp.175-181
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    • 2011
  • Oxidative stress or accumulation of reactive oxygen species (ROS) leads neuronal cellular death and dysfunction, and it contributes to neuronal degenerative disease such as Alzheimer's disease, Parkinson's disease and stroke. Glutamate is one of the major excitatory neurotransmitter in the central nervous system (CNS). Glutamate contributes to fast synaptic transmission, neuronal plasticity, outgrowth and survival, behavior, learning and memory. In spite of these physiological functions, high concentration of glutamate causes neuronal cell damage, acute insults and chronic neuronal neurodegenerative diseases. Heme oxygenase-1 (HO-1) enzyme plays an important role of cellular antioxidant system against oxidant injury. NNMBS020, the water-insoluble fraction of the 70% EtOH extract of root barks of Dictamnus dasycarpus, showed dominant neuroprotective effects on glutamate-induced neurotoxicity in mouse hippocampal HT22 cells by induced the expression of HO-1 and increased HO activity. In mouse hippocampal HT22 cells, NNMBS020 makes the nuclear accumulation of Nrf2 and stimulates extracellular signal-regulated kinase (ERK) pathway. The ERK MAPK pathway inhibitor significantly reduced NNMBS020-induced HO-1 expression, whereas the JNK and p38 inhibitors did not. In conclusion, the water-insoluble fraction of the 70% EtOH extract of root barks of D. dasycarpus (NNMBS020) significantly protect glutamate-induced oxidative damage by induction of HO-1 via Nrf2 and ERK pathway in mouse hippocampal HT22 cells.

Electrochemical Oxidation of Carbon Felt for Redox Flow Battery (Redox flow battery용 carbon felt 전극의 전기화학적 산화)

  • Jung, Young-Guan;Hwang, Gab-Jin;Kim, Jae-Chul;Ryu, Cheol-Hwi
    • Transactions of the Korean hydrogen and new energy society
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    • v.22 no.5
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    • pp.721-727
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    • 2011
  • All vanadium redox-flow battery (VRFB) has been studied actively as one of the most promising electrochemical energy storage systems for a wide rage of applications such as electric vehicles, photovoltaic arrays, and excess power generated by electric power plants at night time. In this study, carbon felt electrodes were treated by electrochemical oxidation with KOH, and the cyclic voltammetry were studied in order to investigate redox reactivity of vanadium ion species with carbon felt electrodes. Besides the effect of electrochemical oxidation on the surface chemistry of carbon felt electrodes were investigated using the X-ray photoelectron spectroscopy (XPS). After electrochemical oxidation, XPS analysis of PAN based GF20-3 carbon felt electrode revealed on increase in the overall surface oxygen content of the carbon felts after electrochemical oxidation. Redox reaction characteristics using cyclic voltammetry (CV) were ascertained that the electrochemical treated electrode were more reversible than the untreated electrode.

Chemical Interaction in Downstream Flows of SNG/Air Symmetric Premixed Counterflow Flame (SNG/Air 예혼합 대향류 대칭화염의 후류 유동장에서 화학적 상호작용)

  • KANG, YEONSE;LEE, KEEMAN
    • Transactions of the Korean hydrogen and new energy society
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    • v.29 no.6
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    • pp.668-679
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    • 2018
  • Experimental and numerical data were compared through a counterflow burner for the characteristic of basic flame about SNG- C11. In order to use the numerical mechanism accurately, the validation was carried out at strain rate ($a_g=30$, $120s^{-1}$) and the UCSD model showed satisfactory results. The effective Lewis number of the extinction boundary, and the behavior of extinction for the symmetric flames of the SNG-C11, could be explained through the trend of $Le_V$, and the flame of the extinction condition was inspected by the major species, key radicals and the chemical reaction paths. The interactions phenomenon in the merged flames has chemical reaction path for producing $HO_2$ were generated at stagnation point. It can be expected the one of major factors in interaction phenomenon.

Emergence of a New Rust Disease of Virginia Creeper (Parthenocissus quinquefolia) through a Host Range Expansion of Neophysopella vitis

  • Na, Dong-Hwan;Lee, Jae Sung;Shin, Hyeon-Dong;Ono, Yoshitaka;Choi, Young-Joon
    • Mycobiology
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    • v.50 no.3
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    • pp.166-171
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    • 2022
  • Virginia creeper (or five-leaved ivy; Parthenocissus quinquefolia) is one of the most popular and widely grown climbers worldwide. In September 2021, Virginia creeper leaves with typical rust symptom were found in an arboretum in Korea, with severe damage. Globally, there is no record of a rust disease on Virginia creeper. Using morphological investigation and molecular phylogenetic inferences, the rust agent was identified as Neophysopella vitis, which is a rust pathogen of other Parthenocissus spp. including Boston ivy (P. tricuspidata). Given that the two ivy plants, Virginia creeper and Boston ivy, have common habitats, especially on buildings and walls, throughout Korea, and that N. vitis is a ubiquitous rust species affecting Boston ivy in Korea, it is speculated that the host range of N. vitis may recently have expanded from Boston ivy to Virginia creeper. The present study reports a globally new rust disease on Virginia creeper, which could be a major threat to the ornamental creeper.

Echinoderm Fauna of Kosrae, The Federation States of Micronesia

  • Lee, Taekjun;Shin, Sook
    • Animal Systematics, Evolution and Diversity
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    • v.29 no.1
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    • pp.1-17
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    • 2013
  • Micronesia is an island nation located north of Papua New Guinea in the Pacific Ocean. A survey was executed on Kosrae, which is one of the four main islands of Micronesia, during January 23-30, 2011 and January 8-15, 2012. The echinoderms were collected at eight intertidal areas and at 12 SCUBA diving points at depths of 10-50 m in the subtidal zone. They were identified based on morphological characteristics. In total, 50 species from 276 individuals were identified: three crinoids, 11 asteroids, seven ophiuroids, 10 echinoids, and 19 holothuroids. Among them, two crinoids, five asteroids, three ophiuroids, four echinoids and two holothuroids were newly recorded from Kosrae.

Particle Emission Characteristics and Measurement of Ultrafine Particles from Laser Printer (사무용기기에서 발생되는 미세입자 측정 및 분석방법 연구)

  • Lee, Kyung Hwan;Kim, Sun Man;Ahn, Kang-Ho
    • Particle and aerosol research
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    • v.6 no.3
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    • pp.123-129
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    • 2010
  • As the indoor activity increases in recent years, the indoor air quality becomes more important. One of the major contaminants in office space is the copy machines and the laser based printers. These devices usually emit nano-particles and chemical species that may give some health effect. The amount of particles generated by the printers and copy machines depend on printer models, printing speed, toners, papers, humidity and so on. To evaluate the emission rate of nano-particles from Laser Printers, the mass concentration measurement method has been used (BAM, 2004). However, the mass concentration measurement method for nano-particles is tedious and time consuming. Therefore, for the development of a new nano-particle counting method, the nano-particle emission characteristics and size distributions are evaluated.

A New Record of Sea Urchin (Echinoidea: Stomopneustoida: Glyptocidaridae) from the Yellow Sea, Korea

  • Lee, Taekjun;Shin, Sook
    • Animal Systematics, Evolution and Diversity
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    • v.29 no.4
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    • pp.312-315
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    • 2013
  • Sea urchins were collected from waters adjacent to Daludo Island and Mohang harbor in the Yellow Sea, and were identified into Glyptocidaris crenularis A. Agassiz, 1864, of the family Stomopneustidae within the order Stomopneustoida, based on morphological characteristics. This species has two unique morphological characteristics: the ambulacral plate is composed of three primary plates and two demi-plates, and a valve of globiferous pedicellaria consists of with a well-developed long terminal hook and a unique stalk equipped with one to six long lateral processes covering membranes, resembling fins. It is newly recorded in Korea and is described with photographs. This brings the total number of sea urchins reported from the Yellow Sea, Korea, to seven.

Recent Advances in Tuberculosis and Nontuberculous Mycobacteria Lung Disease

  • Park, Jae Seuk
    • Tuberculosis and Respiratory Diseases
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    • v.74 no.6
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    • pp.251-255
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    • 2013
  • Tuberculosis (TB) is one of the largest health problems in the world today. And the incidence of nontuberculous mycobacteria (NTM) lung disease appears to be increasing worldwide. Recently, an automated, nucleic acid amplification assay for the rapid detection of both Mycobacterium tuberculosis and rifampin resistance was developed (Xpert MTB/RIF). And fixed-dose combinations of anti-TB drugs and linezolid have been introduced in the treatment of TB. And new NTM species, named Mycobacterium massiliense, which is very closely related to Mycobacterium abscessus was reported. In this review, these recent advances in the diagnosis and treatment of TB and clinical characteristics of M. massiliense lung disease are discussed.