8 research outputs found

    Energy Density of Non-Minimally Coupled Scalar Field Cosmologies

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    Scalar fields coupled to gravity via ξRΦ2\xi R {\Phi}^2 in arbitrary Friedmann-Robertson-Walker backgrounds can be represented by an effective flat space field theory. We derive an expression for the scalar energy density where the effective scalar mass becomes an explicit function of ξ\xi and the scale factor. The scalar quartic self-coupling gets shifted and can vanish for a particular choice of ξ\xi. Gravitationally induced symmetry breaking and de-stabilization are possible in this theory.Comment: 18 pages in standard Late

    Construction of a risk assessment system for chemical residues in agricultural products

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    Objectives Continuous monitoring of chemical residues in agricultural and food products has been performed by various government bodies in South Korea. These bodies have made attempts to systematically manage this information by creating a monitoring database system as well as a system based on these data with which to assess the health risk of chemical residues in agricultural products. Methods Meanwhile, a database system is being constructed consisting of information about monitoring and, following this, a demand for convenience has led to the need for an evaluation tool to be constructed with the data processing system. Results Also, in order to create a systematic and effective tool for the risk assessment of chemical residues in foods and agricultural products, various evaluation models are being developed, both domestically and abroad. Overseas, systems such as Dietary Exposure Evaluation Model: Food Commodity Intake Database and Cumulative and Aggregate Risk Evaluation System are being used; these use the US Environmental Protection Agency as a focus, while the EU has developed Pesticide Residue Intake Model for assessments of pesticide exposure through food intake. Following this, the National Academy of Agricultural Science (NAAS) created the Agricultural Products Risk Assessment System (APRAS) which supports the use and storage of monitoring information and risk assessments. APRAS efficiently manages the monitoring data produced by NAAS and creates an extraction feature included in the database system. Also, the database system in APRAS consists of a monitoring database system held by the NAAS and food consumption database system. Food consumption data is based on Korea National Health and Nutrition Examination Survey. Conclusions This system is aimed at exposure and risk assessments for chemical residues in agricultural products with regards to different exposure scenarios

    Large-Scale Wind Turbine’s Load Characteristics Excited by the Wind and Grid in Complex Terrain: A Review

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    With the development of wind resources under flat terrain, wind farms in extreme wind conditions are developed, and the size of the WT’s rigid-flexible coupling components increases. Therefore, accurately understanding the load characteristics and transmission mechanism of each component plays an important scientific role in improving the reliability of WT (WT) design and operation. Through the collation and analysis of the literature, this review summarizes the research results of large-scale WT load under source–grid coupling. According to the classification of sources, the variation characteristics of different loads are analyzed, and different research methods for different loads are summarized. In addition, the relative merits of the existing improvement schemes are analyzed, and the existing problems are pointed out. Finally, a new research idea of ‘comprehensively considering the coupling effects of source and network factors, revealing WT load characteristics and transmission mechanism’ is summarized. This paper provides important implications for the safety design and reliable operation research of large WTs with complex terrain

    Method Validation for Determination of Thallium by Inductively Coupled Plasma Mass Spectrometry and Monitoring of Various Foods in South Korea

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    Thallium (Tl) is a rare element and one of the most harmful metals. This study validated an analytical method for determining Tl in foods by inductively coupled plasma mass spectrometry (ICP-MS) based on food matrices and calories. For six representative foods, the method’s correlation coefficient (R2) was above 0.999, and the method limit of detection (MLOD) was 0.0070–0.0498 μg kg−1, with accuracy ranging from 82.06% to 119.81% and precision within 10%. We investigated 304 various foods in the South Korean market, including agricultural, fishery, livestock, and processed foods. Tl above the MLOD level was detected in 148 samples and was less than 10 μg kg−1 in 98% of the samples. Comparing the Tl concentrations among food groups revealed that fisheries and animal products had higher Tl contents than cereals and vegetables. Tl exposure via food intake did not exceed the health guidance level

    A Novel T Cell-Engaging Bispecific Antibody for Treating Mesothelin-Positive Solid Tumors

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    As mesothelin is overexpressed in various types of cancer, it is an attractive target for therapeutic antibodies. T-cell bispecific antibodies bind to target cells and engage T cells via binding to CD3, resulting in target cell killing by T-cell activation. However, the affinity of the CD3-binding arm may influence CD3-mediated plasma clearance or antibody trapping in T-cell-containing tissues. This may then affect the biodistribution of bispecific antibodies. In this study, we used scFab and knob-into-hole technologies to construct novel IgG-based 1 + 1 MG1122-A and 2 + 1 MG1122-B bispecific antibodies against mesothelin and CD3ε. MG1122-B was designed to be bivalent to mesothelin and monovalent to CD3ε, using a 2 + 1 head-to-tail format. Activities of the two antibodies were evaluated in mesothelin-positive tumor cells in vitro and xenograft models in vivo. Although both antibodies exhibited target cell killing efficacy and produced regression of xenograft tumors with CD8+ T-cell infiltration, the antitumor efficacy of MG1122-B was significantly higher. MG1122-B may improve tumor targeting because of its bivalency for tumor antigen. It may also reduce systemic toxicity by limiting the activation of circulating T cells. Thus, MG1122-B may be useful for treating mesothelin-positive solid tumors
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