• Analytical Science and Technology
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• v.31 no.6
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• pp.247-258
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• 2018

The purpose of the present study was to investigate whether the degree of air pollution can be evaluated via examination of local plants. Selected sites included two parks in an industrial area, as well as two parks in an urban area. Selected plant samples comprised one-year-old pine shoot leaves. Leaves growing over 2 m from the ground were collected from over 10 pine trees. Leaf surface was analyzed for deposition of 14 trace elements and 16 polycyclic aromatic hydrocarbons (PAHs), including particle size and mass, surface imaging, precipitation-mediated particle removal rate, and concentration. Particle size ranged from 0.4 to $200{\mu}m$, and the volume percentage of particles ${\leq}10$ was 20 %. Deposited particle mass ranged from 0.450-0.825 mg, and precipitation-mediated removal rate ranged from 10.0-27.6 %. Trace element concentration, as measured by ICP/MS after microwave acid digestion, was 18.8-26.3 mg/kg As, 0.08-0.13 mg/kg Be, 0.06-0.08 mg/kg Cd, 4.91-17.8 mg/kg Cr, 5.26-405 mg/kg Cu, 1,930-2,670 mg/kg Fe, 3.03-28.1 mg/kg Pb, 26.9-42.8 mg/kg Mn, 2.66-10.4 mg/kg Ni, 4,560-8,730 mg/kg Al, 2,500-6,120 mg/kg Ba, 5.27-17.8 mg/kg Rb, 40.9-95.3 mg/kg Sr, and 4,030-8,260 mg/kg Zn. Concentration of PAHs, as analyzed by GC/MS/MS after liquid-liquid extraction and purification of deposited particles, ranged from 1.17 to 12.378 mg/kg for ${\Sigma}PAH_{16}$ and from 1.17 to 12.378 mg/kg for ${\Sigma}PAH_7$.

• Economic and Environmental Geology
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• v.27 no.2
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• pp.181-190
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• 1994

Petrochemical study on the micrographic granite distributed in the Wando area, the southernmost part of the Yeongdong-Kwangju depression is performed to investigate the petrogenesis and differentiation processes of the granitic magma. Polarized light microscopy for modal analyses, electron probe microanalyses of feldspars and biotite, inductively coupled plasma analyses for major and trace element contents were adopted in the study. The lithology of the study area consists of Precambrian metasediments, Mesozoic volcanic and sedimentary rocks, and micrographic granite which intrude into the former. The micrographic granite in the Wando area are distributed in the shape of a cauldron. Modal and nonnative mineral analyses of the micrographic granite fall in the area of granite and granodiorite. The chemical composition indicates that the micrographic granite is I-type and magnetite series. The micrographic granite is characterized by more than 90% of micrographic texture in volume percent. Feldspars in the micrographic granite is alkali feldspars (Or, 45~93) and plagioclases (albite to oligoclase). The biotite has a intermediate composition between phlogopite and annite solid solution. The results of the petrochemical studies indicate that the granitic magma of calc-alkaline source materials reactivated in a compressional environment at the continental margin, and then was differentiated by fractional crystallization. The micrographic granite intruded into a shallow level of the crust (5~7 km) in the late Cretaceous.

• Nutrition Research and Practice
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• v.5 no.4
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• pp.357-364
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• 2011

Selenium is an antioxidant trace element linked to cardiovascular disease and cancer. Although diet is a major source, relatively little else is known about independent determinants of selenium levels in free-living humans. In this study, we aimed to investigate the independent demographic. lifestyle, and dietary determinants of selenium levels in 1,997 men and 1,905 women in two large prospective U.S. cohorts. Toenail selenium levels were quantified using neutron activation analysis. Diet, geographic residence, demographic, and environmental factors were assessed by validated self-administered questionnaires. Multivariate generalized linear models were conducted to assess the independent relations of these factors with toenail selenium levels, correcting for measurement error in the diet. In multi variable-adjusted analyses, independent predictors of higher selenium were male gender (6.3% higher levels); living in West and Northern-Midwest U.S. regions (8.9% and 7.4% higher than Southern-Midwest regions, respectively); consumption of beef and bread products (between 0.7 - 2.5% higher per daily serving); and selenium supplement use (6.9% higher than non-users); whereas cigarette smoking (5-10% lower than never smokers), older age (0.6% lower per 5 years), and consumption of eggs, white rice, dairy products, coffee, and alcohol (between 0.1 to 2.0% lower per daily serving) were associated with lower selenium. Multiple dietary and non-dietary factors independently predicted selenium levels, suggesting that both consumption and non-dietary processes (e.g.. related to oxidant status) may affect levels. Significant geographic variation in selenium levels exists in the US.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.1
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• pp.105-117
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• 1994

A finite element procedure which can trace plastic collapse behavior of plane frame structures under small and large deformation is presented. The member is assumed to be prismatic and straight, and has the rectangular or I cross section. For the elasto-plastic analysis, the concept of plastic hinge is introduced and the incremental displacement method is applied. The limit state condition of the plastic hinge is considered under the combined condition of a bending moment and an axial force. Numerical examples are presented in order to demonstrate the validity and efficiency of the proposed procedure.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1741-1745
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• 2005

Zinc is a trace element that is associated with a stimulation of immune function and regulation of ion balance for livestock production. In this study, the effect of zinc as inhibitor to apoptosis-induced cells was examined in vitro using mammary epithelial cell line, HC11 and macrophage cell line, NCTC3749. Cell viability, measured by MTT assay, indicated that 10 g/ml of zinc had a negative impact on cellular activity and 50 ng/ml was chosen for further testing. Apoptosis was induced in cells treated with C2-ceramide in serum-free media. DNA fragmentation and gene expression of acidic sphingomyelinase (a gene responsible for the progress of apoptosis) were distinctively low in zinc treated cells compared with those in non-treated controls. In conclusion, zinc is involved in the regulation of cell proliferation and apoptosis in mammary epithelial cells and macrophages.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.2
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• pp.487-492
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• 2012

Trace element zinc deficiency or excess is implicated in the development or progression of some cancers. The exact role of zinc in the etiology of colon cancer is unclear. To cast light on this question, an experimental model of colon carcinogenesis was applied here. Six week old rats were given sub cutaneous injections of DMH (30 mg/kg body weight) twice a week for three months and sacrificed after 4 months (precancer model) and 6 months (cancer model). Plasma zinc levels showed a significant decrease (p<0.05) at 4 months and a greater significant decrease at 6 months (p<0.01) as compared with controls. In the large intestine there was a significant decrease in tissue zinc levels (p<0.005) and in CuZnSOD, and alkaline phosphatase activity (p<0.05) in the pre-cancerous model and a greater significant decrease in tissue zinc (p<0.0001), and in CuZnSOD and alkaline phosphatase activity (p<0.001), in the carcinoma model. The tissue zinc levels showed a significant decrease in the small intestine and stomach (p<0.005) and in liver (p<0.05) in the cancer model. 87% of the rats in the precancer group and 92% rats in the cancer group showed histological evidence of precancerous lesions and carcinomas respectively in the colon mucosa. This study suggests that the decrease in plasma zinc, tissue zinc and activity of zinc related enzymes are associated with the development of preneoplastic lesions and these biochemical parameters further decrease with progression to carcinoma in the colon.

• The Journal of Society for e-Business Studies
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• v.8 no.3
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• pp.87-105
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• 2003

Business Process Management (BPM) is an emerging trend of managing business process life cycles and integrating heterogeneous systems . Recently, BPM is considered as an essential element for automation of complex business processes involving many companies, particularly for those in an e-Business environment. In such an environment, it is very important for each business partner to trace history of resources. However, it has been a difficult problem for Workflow Management Systems(WFMSs) to support management of resource changes because of limited storage, complex process structure, and absence of formal change model. In this paper. a new framework is proposed, which can support change management for documents, one of core resources of business process. Under a traditional WFMSs framework, all workflow components belong to either build-time or run-time function, and executions of workflow processes are performed by the two functions . To manage changes of documents while process executing. a new framework with additional component modules are required. A version control method is introduced for the purpose of managing document changes. The proposed method includes five models for document structure, process structure, association between process and document, version management, and efficient version storage. A prototype system is developed to demonstrate the effectiveness of the proposed models.

• Journal of Food Hygiene and Safety
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• v.24 no.3
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• pp.267-272
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• 2009

The trace element nutrient selenium discharges its well-known nutritional anti-tumor activity. Converging data from epidemiological, ecological and clinical studies have shown that selenium can decrease the risk for some types of human cancers, especially those of the prostate, lung, and colon. Mechanistic studies have indicated that selenium has many desirable attributes of chemoprevention targeting cancer cells through DNA single strand breaks, the induction of reactive oxygen species. However, there is no reports about the relationship between methylseleninic acid (MSeA), one of methylselenol metabolites and cell cycle arrest in LNCaP human prostate cancer cells. Our data showed that MSeA arrested G1/S pahse of cell cycle arrest and inhibited DNA synthesis in LNCaP cells and those cellular events by MSeA were due to the induction ofp27 protein which is a well-known cyclin-dependent kinase inhibitor. Taken together, cell cycle arrest occurred by MSeA may contribute to the growth-inhibition of prostate cancer cells.

• Journal of Life Science
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• v.18 no.7
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• pp.947-951
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• 2008

Zinc is an essential trace element participating in many physiological functions and notably an important function for sperm physiology. Zinc-enriched yeast strain, Saccharomyces cerevisiae, isolated from tropical fruit rambutan. This strain contained 306 ppm zinc concentration and other components contained by K 28,640 ppm, Mg 2,342 ppm, Na 1,048 ppm, Ca 366 ppm, Fe 236 ppm and Mn 4 ppm. The serum concentration of testosterone was decreased in ethanol treatment rats. As compared with ethanol treated control rats, the zinc-enriched yeast strain supplementation showed significantly increased the testosterone concentration in serum. In addition, zinc concentration in serum was decreased in alcohol treatment, but this reduction was significantly increased by zinc-enriched yeast strain supplementation in ethanol feeding rats. These results indicate that zinc-enriched yeast Saccharomyces cerevisiae strain could play an important role in the sperm physiology by the marked elevation of serum testosterone concentration.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.4
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• pp.868-878
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• 1998

There are recently increasing needs for precision XYZ-stage in the fields of nanotechnology, specially in AFMs(Atomic Force Microscope) and STMs(Scanning Tunneling Microscope). Force measurements are made in the AFM by monitoring the deflection of a flexible element (usually a cantilever) in response to the interaction force between the probe tip and the sample and controlling the force neasyred constant topography can be obtained. The power of the STM is based on the strong distance dependence of the tunneling current in the vacuum chamber and the current is a feedback for the tip to trace the surface topography. Therefore, it is required for XYZ-stage to position samples with nanometer resolution, without any crosscouples and any parasitic motion and with fast response. Nanometer resolution is essential to investigate topography with reasonable shape. No crosscouples and parasitic motion is essential to investigate topography without any shape distortion. Fast response is essential to investigate topography without any undesirable interaction between the probe tip and sample surface ; sample scratch. To satisfy these requirements, this paper presents a novel XYZ-stage concept, it is actuated by PZT and has a monolithic flexible body that is made symmetric as possible to guide the motion of the moving body linearly. PZT actuators have a very fast response and infinite resolution. Due to the monolithic structure, this XYZ-stage has no crosscouples and by symmetry it has no parasitic motion. Analytical modeling of this XYZ-stage and its verification by FEM modeling are performed and optimal design that is to maximize 1st natural frequencies of the stage is also presented and with that design values stage is manufactured.