• Environmental Analysis Health and Toxicology
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• v.18 no.2
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• pp.155-163
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• 2003

Fluoranthene, a common polycyclicaromatic hydrocarbon (PAH), exhibits phototoxicity which may affect aquatic organisms. The eventual goal of this study is to develop a biomarker of Japanese medaka (Oryzias latipes) used in monitoring hazardous chemicals in the ecosystem. In this study we investigated neural toxicity of fluoranthene in Japanese medaka (Oryzias latipes) along with comparative analysis of corresponding behavioral response. The untreated individuals shooed normal behavioral characteristics (i. e., smooth and linear movements). The treated fish, however, showed stopping and abrupt change of orientation (100 ppb), and severely reduced locomotive activity and enhanced surfacing activity (1,000 ppb). Treatment of the medaka fish with fluoranthene caused a significant suppresson of acetycholine esterase (AChE) activities in the body portion but not in the head portion. When fish were exposed to 1,000 ppb of fluoranthene for 24 hr, the body AChE activities decreased from 126.${\pm}$31.89 (nmoles substrate hydrolyzed per min per mg protein) to 49.51${\pm}$11.99. Expressions of tyrosine hydroxylase (TH) protein in the different organs from both head and body portions were comparatively analyzed using an immunohistochemical technique. Five organs of the medaka fish showing a strong TH protein expression were the olfactory bulb, hypothalamus, optic lobe, pons and myelencephalon regions. This study provides molecular and neurobehavioral bases of a biomonitoring system for toxic chemicals using fish as a model organism.

• Journal of the Korean earth science society
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• v.29 no.5
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• pp.428-436
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• 2008

This study observed the upper tropospheric ozone enhancement in the northern Atlantic for the Aerosols99 campaign in January-February 1999. To find the origin of this air, we have analyzed the horizontal and vertical fields of Isentropic Potential Vorticity (IPV) and Relative Humidity (RH). The arch-shaped IPV is greater than 1.5 pvus indicating stratospheric air stretches equatorward. These arch-shaped regions are connected with regions of RH less than 20%. The vertical fields of IPV and RH show the folding layer penetrating into the upper troposphere. These features support the idea that the upper tropospheric ozone enhancement originated from the stratosphere. Additionally, we have investigated the climatological frequency of stratospheric intrusion over the tropical north Atlantic using IPV and RH. The total frequency between the equator and $30^{\circ}N$ over the tropical north Atlantic exhibits a maximum in northern winter. It suggests that the stratospheric intrusion plays an important role in enhancing ozone in the upper troposphere over the tropical north Atlantic in winter and early spring. Although the tropospheric ozone residual method assumed zonally invariant stratospheric ozone, stratospheric zonal ozone variance could be caused by stratospheric intrusions. This implies that stratospheric intrusion influences ozone variance over the Atlantic in boreal winter and spring, and the intrusion is a possible source for the tropical north Atlantic paradox.

• Economic and Environmental Geology
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• v.13 no.2
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• pp.104-116
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• 1980

The Ulsan mine is one of the largest contact metasomatic magnetite and scheelite deposits in the southeastern part of Korea. Mineralization at the Ulsan mine is localized along the contact between upper Cretaceous volcanic rocks and age unknown limestone which were intruded by 58 m.y. -old biotite-horndlende granite. General zonal sequence of skarn toward crystalline limestone from limestone-volcanics contact is grandite, grandite-salite and salite zones. On the otherhand volcanics origin skarns exhibits zonal sequences toward hornfels from boundary with limestone is garnet, garnet-epidote, and epidote zone. Compositions of garnets and clinopyro xenes are determined by the X-ray diffraction and reflective indecies. Local brecciation of these early skarns were followed by formation of the later skarn as zoned patches, breccia fillings and cross-cutting veins. Paragenetic sequence of late skarn minerals which is exhibited in the zoned patches and veins is an overlapping progression with time from andradite through hedenbergite or actinolite, quartz to calcite deposition. Magnetite metallization followed early formed skarns and pyrite pyrrhoite, sphalerite, galena, tennantite, scheelite and arsenopyrite deposition were simultaneously with hedenbergite, quartz and calcite of late skarn. Filling temperatures of fluid inclusions in calcites range from $160^{\circ}$ to $280^{\circ}C$.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.1
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• pp.9-13
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• 2007

Hexane extract of Porteresia coarctata (Roxb.) exhibits a toxic effect on the tissues of Spodoptera litura (F) while fed at the dose of 1000 and 2000 ppm thoroughly mixing with castor leaves (Ricinus communis L) after dissolving in DMSO at late fourth instar whereas only DMSO treated castor leaves were fed to control group. The larvae were put to rear at $28^{\circ}C{\pm}1^{\circ}C$, $76{\pm}4%$ R.H. under 12 L + 12 D photoperiodic regime. In test group insects substantial reduction of protein and DNA content was marked in fat body and midgut tissues compared to DMSO treated control group. The significant biochemical alterations in the midgut tissues and fat body of test group insects indicate the insecticidal property of the said plant extract that could be tested in facilitating the phenomenal stride in Integrated Pest Management.

• Mass Spectrometry Letters
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• v.9 no.3
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• pp.81-85
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• 2018

In this study, the chemical composition of bacterial melanin isolated from the Streptomyces glaucescens strain was elucidated by ultra-high-resolution Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. Ultra-high-resolution mass profiles of the microbial melanin product were acquired using a 15 Tesla FT-ICR mass spectrometer in positive and negative ion modes via electrospray ionization to obtain more complete descriptions of the molecular compositions of melanin-derived organic constituents. A mass resolving power of 500,000 (at m/z 400) was achieved for all spectra while collecting 400 scans per sample with a 4 M transient. The results of this analysis revealed that the melanin pigment isolated from S. glaucescens predominantly exhibits CHON and CHO species, which belong to the proteins class of compounds, with the mean C/O and C/N ratios of 4.3 and 13.1, thus suggesting that the melanin could be eumelanin. This analytical approach could be utilized to investigate the molecular compositions of a variety of natural or synthetic melanins. The compositional features of melanins are important for understanding their formation mechanisms and physico-chemical properties.

• Steel and Composite Structures
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• v.22 no.2
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• pp.323-352
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• 2016

The results of a series of finite element (FE) simulations and experimental studies are used to develop strength and stiffness models that predict the failure capacity and response characteristics of unstiffened extended endplate connections with circular and rectangular bolt configurations associated with deep girders. The proposed stiffness models are composed of multi-linear springs which model the overall extended endplate/column flange system deformation and strength of key-components. Comparison of model predictions with FE and experimental results available in the literature show that the proposed models accurately predict the strength and the response of extended endplate/column system with circular and rectangular bolt configurations. The effect of the bolt configuration (circular and rectangular) on the prying phenomenon encountered in the unstiffened extended endplate/column system was investigated. Based on FE results, extended endplate with circular bolt configuration has a more ductile behavior and exhibits higher total prying forces. The proposed models can be used to design connections that cover all possible failure modes for extended endplate with circular bolt configuration. This study provides guidelines for engineers to account for the additional forces induced in the tension bolts and for the maximum rotational capacity demand in the connection which are required for seismic analysis and design.

• Atmosphere
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• v.25 no.3
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• pp.461-472
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• 2015

The sudden stratospheric warming (SSW), which is characterized by an abrupt increase of polar stratospheric temperature by several tens of degrees in a week, has been known to affect tropospheric weather and climate on sub-seasonal time scale in the boreal winter. Such downward coupling has been often examined in North Atlantic and Europe, but rarely examined in East Asia. In this study, by applying the two definitions of SSW to the reanalysis data, the possible impacts of the SSW events on the surface air temperature (SAT) and tropospheric circulation in East Asia are analyzed. It is found that Eurasian continent, including Siberia and the Northeast Asia, tends to experience anomalously cold SAT for up to sixty days after the SSW events. The resulting SAT anomalies largely resemble those associated with negative Artic Oscillation. However, over East Asia, SSW-related SAT change is weak and not statistically significant. Only during the extreme SSW events when the downward coupling between the stratosphere and troposphere is strong, East Asia exhibits significantly cold SAT anomalies. This relationship is presented by grouping SSW events into those followed by cold SAT anomalies over East Asia and those by warm anomalies for varying threshold values of the SSW events.

• Journal of Dairy Science and Biotechnology
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• v.27 no.1
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• pp.19-28
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• 2009

Lactoferrin was first identified 60 years ago as a "red protein" in bovine milk. Lactoferrin, one of the transferrin family proteins, is an iron-binding glycoprotein found in milk and various mucosal secretions; it is also released from activated neutrophils. Human lactoferrin has a molecular weight of 82.4 kDa and is composed of 702 or 692 amino acid residues. Bovine lactoferrin has a molecular weight of 83.1 kDa and is composed of 689 amino acid residues. Both lactoferrin and transferrin have the ability to bind two $Fe^{3+}$ ions, together with two ${CO_3}^{2-}$ ions with extremely high affinity; these proteins also have the ability to release this iron at low pH levels. The polypeptide chain in lactoferrin is folded into two globular lobes, representing the N-terminal and C-terminal halves. Both lobes have similar folding and 40% sequence identity. This protein is capable of multiple functions as described in various review papers, including antimicrobial, antiviral, antiinflammatory, anticancer, antioxidant, and cell growth-promoting activities. Lactoferrin also exhibits immunomodulating effects and plays an active role in the regulation of myelopoiesis and the inhibition of bacterial translocation.

• Atmosphere
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• v.20 no.3
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• pp.333-341
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• 2010

The stratiform rain fraction is investigated in the tropical boreal winter Madden-Julian oscillation (MJO) and summer intraseasonal oscillation (ISO) using Tropical Rainfall Measuring Mission (TRMM) Precipitation Rader data for the 11-yr period from 1998 to 2008. Composite analysis shows that the MJO/ISO produces larger stratiform rain rate than convective rain rate for nearly all phases following the propagating MJO/ISO deep clouds, with the greatest stratiform rainfall amount when the MJO/ISO center is located over the central-eastern Indian Ocean and the western Pacific. The fraction of the intraseasonally filtered stratiform rainfall compared to total rainfall (i.e., convective plus stratiform rainfall) amounts to 53~56%, which is 13~16% larger than the stratiform rain fraction estimated for the same data on seasonal-to-annual time scales by Schumacher and Houze. This indicates that the MJO/ISO exhibits the organized rainfall process which is characterized by the shallow convection/heating at the incipient phase and the subsequent flare-up of strong deep convection, followed by the development of stratiform clouds at the upper troposphere.

• Economic and Environmental Geology
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• v.27 no.5
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• pp.459-467
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• 1994

The Gadaeri granite near Ulsan mine is an oval-shape isolated granitic body, and is genetically related to the iron-tungsten mineralization. The Gadaeri granite exhibits calc-alkaline and I-type characteristics, and generally shows the micrographic texture which indicates the shallow depth of emplacement. Consideration of the stratigraphic thickness of Ulsan formation and minimum-melt compositions suggests that the bulk magma crystallized at pressure of 0.5~2.0 kbar under water saturated condition. The evolutionary trend observed in the studied rocks represents that feldspar fractional crystallization has been a major magmatic process at the Gadaeri granite pluton. Different chemical characteristics between the Gadaeri and the Masan-Kimhae granites cannot be explained by fractional crystallization or different degrees of partial melting, and it reflects that the magma source for Gadaeri granite was different from that of the Masan and Kimhae granites.