• Ocean and Polar Research
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• v.37 no.2
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• pp.127-140
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• 2015

A continuous series of 60 snow samples was collected at a 2.5-cm interval from a 1.5-m snow pit at a site on the Styx Glacier Plateau in Victoria Land, Antarctica, during the 2011/2012 austral summer season. Various chemical components (${\delta}D$, ${\delta}^{18}O$, $Na^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, $SO_4{^2-}$, $NO_3{^-}$, $F^-$, $CH_3SO_3{^-}$, $CH_3CO_2{^-}$ and $HCO_2{^-}$) were determined to understand the highly resolved seasonal variations of these species in the coastal atmosphere near the Antarctic Jang Bogo station. Based on vertical profiles of ${\delta}^{18}O$, $NO_3{^-}$and MSA, which showed prominent seasonal changes in concentrations, the snow samples were dated to cover the time period from 2009 austral winter to 2012 austral summer with a mean accumulation rate of $226kgH_2Om^{-2}yr^{-1}$. Our snow profiles show pronounced seasonal variations for all the measured chemical species with a different pattern between different species. The distinctive feature of the occurrence patterns of the seasonal variations is clearly linked to changes in the relative strength of contributions from various natural sources (sea salt spray, volcanoes, crust-derived dust, and marine biogenic activities) during different short-term periods. The results allow us to understand the transport pathways and input mechanisms for each species and provide valuable information that will be useful for investigating long-term (decades to century scale periods) climate and environmental changes that can be deduced from an ice core to be retrieved from the Styx Glacier Plateau in the near future.

• Korean Journal of Environmental Biology
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• v.21 no.4
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• pp.384-391
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• 2003

The induction of chromosome aberrations in Hordeum vulgare germs after irradiation is studied for the dose range of 10 to 1,000 mGy. The relationship between the frequency of aberrant cells and the absorbed dose is shown to be non -linear and has a dose-independent plateau within the range of 56-467 mGy where the level of cytogenetic damage is statistically significantly distinguished from the spontaneous level. The comparison of the goodness of the experimental data fitting with mathematical models of different complexities, using the most common quantitative criteria, demonstrates the benefit of the piecewise linear model over the linear and polynomial ones in approximating the cytogenetical disturbance frequency. The results of our study support the conclusion about indirect mechanism of chromosome aberrations induced by low doses or dose rates mutagenesis.

• Journal of the Korean Geographical Society
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• v.41 no.5 s.116
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• pp.623-629
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• 2006

At present, 3 names about undersea features in the East Sea - Korean Plateau, Tsushima Basin, Syun-yo Bank - are listed on Gazetteer Any explanations are not given for registration of these names. Just it seems that the names written on International marine chart(INT 511) were recorded to Gazetteer. Furthermore Tsushima Basin and Syun-yo Bank have no oceanographic, geologic reason and geographical relevance, and the names should be replaced by Ulleung Basin and Isabu Tablemount, respectively, that is deeply related to geographical relevance and genetic origin.

• Archives of Pharmacal Research
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• v.21 no.2
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• pp.135-139
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• 1998

High titer rabbit polyclonal antibodies (pAbs) which show a specificity for saikosaponin a (SSA), have been generated. The immunogen used was a conjugate of SSA linked through its glucose moiety to bovine serum albumin by periodate oxidation method. The antibody titers obtained from two rabbits, innoculated with the immunogen, reached a plateau after the fourth and third booster injection, respectively. The specificity of the pAbs was determined by hapten inhibition assays using several SSA-like structures. SSA competitively inhibited the binding of the rabbit anti-SSA pAbs to SSA-ovalbumin on solid phase, a coated antigen on the well. The antibodies showed high specificity to SSA, exhibiting no significant cross-reactivity with any of SSA analogues tested.

• Korea-Australia Rheology Journal
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• v.20 no.1
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• pp.35-42
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• 2008

An inverse ferrofluid composed of micron sized polymethylmethacrylate particles dispersed in ferrofluid was used to investigate the effects of test duration times on determining the flow curves of these materials under constant magnetic field. The results showed that flow curves determined using low duration times were most likely not measuring the steady state rheological response. However, at longer duration times, which are expected to correspond more to steady state behaviour, we noticed the occurrence of plateau and decreasing flow curves in the shear rate range of $0.004\;s^{-1}$ to ${\sim}20\;s^{-1}$, which suggest the presence of nonhomogeneities and shear localization in the material. This behaviour was also reflected in the steady state results from shear start up tests performed over the same range of shear rates. The results indicate that care is required when interpreting flow curves obtained for inverse ferrofluids.

• International Journal of High-Rise Buildings
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• v.2 no.4
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• pp.285-291
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• 2013

This paper proposes a framework for understanding the energy consumption differences between tall and low-rise buildings. Energy usage data from 706 office buildings in New York illustrates expected correlations from the framework. Notable correlations include: taller buildings tend to use more energy until a plateau at 30~39 floors; tall buildings in Manhattan use 20% more energy than low-rise buildings in Manhattan, while tall buildings outside Manhattan use 4% more energy than low-rise buildings outside Manhattan. Additional correlations are discussed, among which is the trend that the Energy Star program in New York City assigns higher ratings to tall buildings with higher EUIs than low-rise buildings with the same EUI. Since Energy Star is based on regressions of existing buildings, the Energy Star ratings suggest taller buildings have higher EUIs than shorter buildings, which is confirmed by the New York City energy benchmarking data.

• Toxicological Research
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• v.7 no.2
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• pp.173-181
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• 1991

Membrane transport of brazilin was investigated i primary cultured rat hepatocytes. Brazilin was transported into hepatocytes very slowly and reached plateau at about 60 minutes. Saturation of transport process was not observed and the transport was not affected by ouabain, metabolic inhibitors, and its structural analog. The amount of brazilin transported into hepatocytes was decreased when the environmental temperature was decreased. These results suggest that brazilin might be transported into hepatocytes by simple diffusional process.

• Parasites, Hosts and Diseases
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• v.57 no.6
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• pp.627-633
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• 2019

The study of coprolites has been a theme of archaeology in the American Southwest. A feature of archaeoparasitology on the Colorado Plateau is the ubiquity of pinworm infection. As a crowd parasite, this ubiquity signals varying concentrations of populations. Our recent analysis of coprolite deposits from 2 sites revealed the highest prevalence of infection ever recorded for the region. For Salmon Ruins, the deposits date from AD 1140 to 1280. For Aztec Ruins, the samples can be dated by artifact association between AD 1182-1253. Both sites can be placed in the Ancestral Pueblo III occupation (AD 1100-1300), which included a period of cultural stress associated with warfare. Although neither of these sites show evidence of warfare, they are typical of large, defensible towns that survived this time of threat by virtue of large populations in stonewalled villages with easily accessible water. We hypothesize that the concentration of large numbers of people promoted pinworm infection and, therefore, explains the phenomenal levels of infection at these sites.

• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.163-165
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• 2012

Impedance spectroscopy informs electrical properties of materials as accumulated charges, contact status between electrode and organic materials. We carried out impedance spectroscopy of organic light-emitting diodes as ITO/Alq3(60 nm)/Al on temperatures from 10 K to 300 K. The result described Z'-Z" plot, cole-cole plot and dielectric relaxation time τ. Z'-Z" plot means that real and imaginary part of materials in organic and electrode by frequencies and temperature. Z' as real part of impedance by applied frequency depending on temperature shows the plateau in low frequency region as Rs+ Rp and over 100 kHz in high frequency region as Rs. Cole-cole plot shows resistance of materials in equivalent circuit of the device by temperatures. And equivalent circuit and dielectric relaxation could be accomplished by using the complex impedance analysis.

• Analytical Science and Technology
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• v.21 no.6
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• pp.474-479
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• 2008

Radioactivity of naturally occurring radioactive nuclides (NORN) such as $^{226}Ra$, $^{228}Ac$ and $^{40}K$ were investigated for surface sediments collected from Ordos, Alashan, Taklimakan deserts and Loess plateau regions in China. By a Gamma-ray spectrometry, specific activity (SA) and SA ratio (SAR) of the NORN were determined for each source region of Asian dust. Characterization of the source regions of Asian dust was performed with the SA and SAR values. SA of $^{226}Ra$ in the three desert regions have almost same values in the range of mean value 17.9~21.9 Bq/kg, however, the SA in Loess Plateau has much higher values in the mean value of 35 Bq/Kg. SA of $^{228}Ac$ in the Ordos and Alashan desert regions have almost same values in the range of mean value 27.1~27.2 Bq/kg, and those in Taklimakan desert and Loess Plateau were 31.7 and 49.0 Bq/kg, respectively. In case of 40K, the SA in all regions have similar values in the range of 636~943 Bq/kg. The mean SAR value of $^{226}Ra/^{228}Ac$ in four source regions was almost same in the range of 0.708-0.721. It is shown that relationship between $^{226}Ra$ and $^{228}Ac$ is clearly presented in the source regions. The mean SAR values of $^{226}Ra/^{40}K$, $^{228}Ac/^{40}K$ are 0.0209-0.056, 0.0287-0.0773, respectively.