• Mass Spectrometry Letters
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• v.4 no.4
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• pp.87-90
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• 2013

Isotope amount ratios of lead in a bronze sample have been successfully determined using multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS). Matrix separation conditions were tested and optimized using ion exchange chromatography with anion-exchange resin, AG1-X8, and sequential elution of the 0.5 M HBr and 7 M $HNO_3$ to separate lead from very high contents of copper and tin in bronze matrix. Mercury was also removed efficiently in the optimized separation condition. The instrumental isotope fractionation of lead in the MC-ICP-MS measurement was corrected by the external standard sample bracketing method using an external standard, NIST SRM 981 lead common isotope ratio standard followed by correction of procedure blank to obtain reliable isotope ratios of lead. The isotope ratios, $^{206}Pb/^{204}Pb$, $^{207}Pb/^{204}Pb$, $^{208}Pb/^{204}Pb$, and $^{208}Pb/^{206}Pb$, of lead were determined as $18.0802{\pm}0.0114$, $15.5799{\pm}0.0099$, $38.0853{\pm}0.0241$, and $2.1065{\pm}0.0004$, respectively, and the determined isotope ratios showed good agreement with the reference values of an international comparison for the same sample within the stated uncertainties

• Mass Spectrometry Letters
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• v.4 no.4
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• pp.75-78
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• 2013

A gas chromatography/mass spectrometric (GC/MS) method was developed as a candidate reference method for the accurate determination of essential fatty acids (linoleic acid, ${\alpha}$- and ${\gamma}$-linolenic acids) in food supplemental oil products. Samples were spiked with three internal standards (stearic acid-$d_{35}$, $^{13}C_{18}$-linoleic acid, and $^{13}C_{18}$-${\alpha}$-linolenic acid). Samples were then subject to saponification, derivatization for methylation, and extraction by organic solvent. For GC/MS measurement, an Agilent HP-88 column, designed for the separation of fatty acid methyl esters, was selected after comparing with other columns as it provided better separation for target analytes. Target analytes and internal standards were detected by selected ion monitoring of molecular ions of their methyl ester forms. The GC/MS method was applied for the measurement of three botanical oils in NIST SRM 3274 (borage oil, evening primrose oil, and flax oil), and measurement results agreed with the certified values. Measurement results for target analytes which have corresponding isotope-labeled analogues as internal standard were calculated based on isotope dilution mass spectrometry (IDMS) approach, and compared with results calculated by using the other two internal standards. Results from the IDMS approach and the typical internal standard approach were in good agreement within their measurement uncertainties. It proves that the developed GC/MS method can provide similar metrological quality with IDMS methods for the measurement of fatty acids in natural oil samples if a proper fatty acid is used as an internal standard.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.4
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• pp.1615-1619
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• 2015

Background: Promoter hypermethylation mediated gene silencing of tumor suppressor genes is considered as most frequent mechanism than genetic aberrations such as mutations in the development of cancers. BRD7 is a single bromodomain containing protein that functions as a subunit of SWI/SNF chromatin-remodeling complex to regulate transcription. It also interacts with the well know tumor suppressor protein p53 to trans-activate genes involved in cell cycle arrest. Loss of expression of BRD7 has been observed in breast cancers and nasopharyngeal carcinomas due to promoter hypermethylation. However, the genetic status of BRD7 in oral squamous cell carcinomas (OSCCs) is not known, although OSCC is one of the most common among all reported cancers in the Indian population. Hence, in the present study we investigated OSCC samples to determine the occurrence of hypermethylation in the promoter region of BRD7 and understand its prevalence. Materials and Methods: Genomic DNA extracted from biopsy tissues of twenty three oral squamous cell carcinomas were digested with methylation sensitive HpaII type2 restriction enzyme that recognizes and cuts unmethylated CCGG motifs. The digested DNA samples were amplified with primers flanking the CCGG motifs in promoter region of BRD7 gene. The PCR amplified products were analyzed by agarose gel electrophoresis along with undigested amplification control. Results: Methylation sensitive enzyme technique identified methylation of BRD7 promoter region seventeen out of twenty three (74%) well differentiated oral squamous cell carcinoma samples. Conclusions: The identification of BRD7 promoter hypermethylation in 74% of well differentiated oral squamous cell carcinomas indicates that the methylation dependent silencing of BRD7 gene is a frequent event in carcinogenesis. To the best of our knowledge, the present study is the first to report the occurrence of BRD7and its high prevalence in oral squamous cell carcinomas.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.4
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• pp.1599-1603
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• 2015

Background: Epigenetic silencing of tumor suppressor genes due to promoter hypermethylation is one of the frequent mechanisms observed in cancers. Hypermethylation of several tumor suppressor genes involved in cell cycle regulation has been reported in many types of tumors including oral squamous cell carcinomas. LATS1 (Large Tumor Suppressor, isoform 1) is a novel tumor suppressor gene that regulates cell cycle progression by forming complexes with the cyclin dependent kinase, CDK1. Promoter hypermethylation of the LATS1 gene has been observed in several carcinomas and also has been linked with prognosis. However, the methylation status of LATS1 in oral squamous cell carcinomas is not known. As oral cancer is one of the most prevalent forms of cancer in India, the present study was designed to investigate the methylation status of LATS1 promoter and associate it with histopathological findings in order to determine any associations of the genetic status with stage of differentiation. Materials and Methods: Tumor chromosomal DNA isolated from biopsy tissues of thirteen oral squamous cell carcinoma biopsy tissues were subjected to digestion with methylation sensitive HpaII enzyme followed by amplification with primers flanking CCGG motifs in promoter region of LATS1 gene. The PCR amplicons were subsequently subjected to agarose gel electrophoresis along with undigested amplification control. Results: HpaII enzyme based methylation sensitive PCR identified LATS1 promoter hypermethylation in seven out of thirteen oral squamous cell carcinoma samples. Conclusions: The identification of LATS1 promoter hypermethylation in seven oral squamous cell carcinoma samples (54%), which included one sample with epithelial dysplasia, two early invasive and one moderately differentiated lesions indicates that the hypermethylation of this gene may be one of the early event during carcinogenesis. To the best of our knowledge, this is the first study to have explored and identified positive association between LATS1 promoter hypermethylation with histopathological features in oral squamous cell carcinomas.

• Journal of Advanced Navigation Technology
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• v.13 no.6
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• pp.957-963
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• 2009

It is necessary for the resource management system to manage for the resource in distributed networking environment. Because of increasing the complexity of vast computer system and business environment, needs of RMS is increasing. Based on the common information model to use of objected oriented technology, through analysis of the reference model for the resource management system of the SNIA, we intend to implement the application program to manage the NGS system that consist of SSD and DRAM. To visualize, it is use the GUI Interface. It is possible for application program(Client) to detect and manage the system that consist of the NGS system. Also, status information that is divided into three cataloges(Minor/Major/Critical) can be displayed and it provide support of configuration functionality to manage devices.

• International Journal of Fluid Machinery and Systems
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• v.2 no.4
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• pp.295-302
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• 2009

The flow in the draft tube cone of Francis turbines operated at partial discharge is a complex hydrodynamic phenomenon where an incoming steady axisymmetric swirling flow evolves into a three-dimensional unsteady flow field with precessing helical vortex (also called vortex rope) and associated pressure fluctuations. The paper addresses the following fundamental question: is it possible to compute the circumferentially averaged flow field induced by the precessing vortex rope by using an axisymmetric turbulent swirling flow model? In other words, instead of averaging the measured or computed 3D velocity and pressure fields we would like to solve directly the circumferentially averaged governing equations. As a result, one could use a 2D axi-symmetric model instead of the full 3D flow simulation, with huge savings in both computing time and resources. In order to answer this question we first compute the axisymmetric turbulent swirling flow using available solvers by introducing a stagnant region model (SRM), essentially enforcing a unidirectional circumferentially averaged meridian flow as suggested by the experimental data. Numerical results obtained with both models are compared against measured axial and circumferential velocity profiles, as well as for the vortex rope location. Although the circumferentially averaged flow field cannot capture the unsteadiness of the 3D flow, it can be reliably used for further stability analysis, as well as for assessing and optimizing various techniques to stabilize the swirling flow. In particular, the methodology presented and validated in this paper is particularly useful in optimizing the blade design in order to reduce the stagnant region extent, thus mitigating the vortex rope and expending the operating range for Francis turbines.

• Economic and Environmental Geology
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• v.27 no.5
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• pp.469-477
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• 1994

Many researchers have investigated most representative sequential extraction method using various reagents for determining the chemical forms of metals in soils and sediments. In this paper, a newly modified method for sequential extraction scheme based on Tessier's method by Environmental Geochemistry Research, Centre for Environmental Technology, Imperial College, was introduced and examined. In comparison with Tessier's method, originally designed for sediment analysis by Atomic Absorption Spectrophotometry (AAS), the sequential extraction scheme has been developed for the multi-element analysis by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The partitioning of particulate trace elements was classified into five fractions: (i) exchangeable, (ii) bound to carbonates or specially adsorbed, (iii) bound to Fe and Mn oxides, (iv) bound to organic matter and sulphides and (v) residuals. The experimental results of the pilot study for in-house reference material (HRM2) and certified international standard reference material (SRM2711) using the modified method showed not only reasonable precision and accuracy but also acceptable overall recovery rates. In addition, mine dump soils sampled in the Dalsung Cu-W mine, Korea were prepared and sequentially extracted using the method. Most of Cu was bound to organic matter/sulphides and residual fractions. The dominant fraction of soil Pb and Zn in the study area was found in the residuals. The fraction of Cd showed a wide variation between samples and could be found bound to the carbonates or specially adsorbed, oxides, organic fraction and residuals. The recovery rates of Cd, however, were poor due to relatively low Cd concentrations in soils. The heavy metals in these mine dumps appear to be in the more inert forms and should not be readily bioavailable. The soils, however, had very low pH values (average 4.1) and had sandy textures; consequently, rapid infiltration of rainfall may increase leaching of Zn and Cd which were found to be around 5 to 10% of the exchangeable fraction. As a result of the investigation of this study, it has been strongly recommended that these mine waste materials should still be considered a significant contaminant source and will need environmental remediation to prevent pollutants from being released into the environment.

• Analytical Science and Technology
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• v.8 no.1
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• pp.9-16
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• 1995

The low concentration of cadmium in the whole-blood was determined by graphite furnace atomic absorption spectrometry(GFAAS) after the sample was diluted five-fold by 1% Triton X-100, 2% $(NH_4)_2HPO_4$ as matrix modifier and pyrocoated graphite tube with L'vov platform was tried remove the interferences of blood matrix and reduce the loss of volatility of cadmium at higher ashing temperature($600^{\circ}C$). The criteria for evaluating the accuracy and precision of this analysis was confirmed by analysis of interlaboratory comparison(Japan) and NIST SRM No. 909(Cd in Serum). The limit of the determination for cadium was 0.1ng/ml and the relative standard deviation(RSD) at 1.0ng/ml level was about 10% for the GFAAS.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.2
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• pp.116-121
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• 1998

For the application of study on pollution and conservation of environment determination of 33 elemental concetrations in different sediment samples were carried out using instrumental neutron activation analysis (INAA). For verification and evaluation of the analytical method, three standard reference materials (two NIST SRMs and one NRCC CRM) were chosen and the accuracy and precision of the analysis were estimated by comparison to the certified values. Under the optimum condition, the analytical procedure to apply a practical sample was estimated. Neutron irradiation of sample was done at the irradiation facilities (neutron flux, 1-3${\times}$10$\^$13/n/$\textrm{cm}^2$$.$s) of the TRIGA MARK-III and HANARO research reactor in the Korea Atomic Energy Research Institute. In addition, analysis of two IAEA's sediment was performed according to the pre-established analytical method. The analytical results of elements such as Al, As, Co, Cr, Fe, Sb and Zn by INAA were intercompared with those of WD-XRF, ICP-MS and AAS, and are relatively agreed with each other.

• Journal of Oriental Neuropsychiatry
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• v.31 no.3
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• pp.213-223
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• 2020

Objectives: To determine treatment effects of a combination of interpersonal and social rhythm therapy and Korean medicine for a patient with major depressive episode of bipolar II disorder. Methods: A patient was treated with Korean medicine (acupuncture, herbal medicine, etc.) and interpersonal and social rhythm therapy (IPSRT) for four months. Pattern identification for depressive mood and sleep associated symptoms was evaluated using Patient Health Questionnaire-9 (PHQ-9) and Social rhythm metric II-5 (SRM II-5). Results: At the end of the treatment, depression and delayed sleep symptoms were improved and social rhythm was recovered to the regular range. The patient acquired an insight to his interpersonal tensions and conflicts. Conclusions: Korean medicine in combination with interpersonal and social rhythm therapy can be used to treat patients with major depressive episode of bipolar II disorder. More cases are needed to develop guidelines for treating bipolar disorder.