• Title/Summary/Keyword: $Cac_2$

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Development of Analytic Methods for Veterinary Drug Residue in Animal Products by Liquid Chromatography-Mass Spectrometry (축산물 중 잔류 성장보조제 분석을 위한 액체크로마토그라피-질량분석법 개발 및 적용)

  • Lee, Soo Hyun
    • Journal of Convergence for Information Technology
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    • v.11 no.2
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    • pp.107-116
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    • 2021
  • In this study, an analytical method was developed for estradiol-17��, testosterone, and progesterone, which are growth promoters as veterinary drug residues in animal food. The analytes were separated using liquid chromatography, and was injected into a mass spectrometer through the electrospray ionization(ESI) process and detected in multiple reaction monitoring(MRM) mode. As the method was validated by CODEX CAC/GL 71-2009 guideline, it met the acceptable. The analysis of beef, pork, and chicken distributed in Korea was conducted with an established method to confirm the applicability of the actual sample. It was confirmed that the developed method can be quickly and reliably in the analysis for the growth promoters identified in domestic distributed livestock products. Through subsequent research, a highly utilized analysis method will be completed if the number of growth promoters is expanded based on the method and the simultaneous analytical method is established by including all of it.

Relationship between Incidental Abnormalities on Screening Thoracic Computed Tomography and Mortality: A Long-Term Follow-Up Analysis

  • Jong Eun Lee;Won Gi Jeong;Hyo-Jae Lee;Yun-Hyeon Kim;Kum Ju Chae;Yeon Joo Jeong
    • Korean Journal of Radiology
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    • v.23 no.10
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    • pp.998-1008
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    • 2022
  • Objective: The present study aimed to assess the relationship between incidental abnormalities on thoracic computed tomography (CT) and mortality in a general screening population using a long-term follow-up analysis. Materials and Methods: We retrospectively collected the medical records and CT images of 840 participants (mean age ± standard deviation [SD], 58.5 ± 6.7 years; 564 male) who underwent thoracic CT at a single health promotion center between 2007 and 2010. Two thoracic radiologists independently reviewed all CT images and evaluated any incidental abnormalities (interstitial lung abnormality [ILA], emphysema, coronary artery calcification [CAC], aortic valve [AV] calcification, and pulmonary nodules). Kaplan-Meier analysis with log-rank and z-tests was performed to assess the relationship between incidental CT abnormalities and all-cause mortality in the subsequent follow-up. Cox proportional hazards regression was performed to further identify risk factors of all-cause mortality among the incidental CT abnormalities and clinical factors. Results: Among the 840 participants, 55 (6%), 171 (20%), 288 (34%), 396 (47%), and 97 (11%) had findings of ILA, emphysema, CAC, pulmonary nodule, and AV calcification, respectively, on initial CT. The participants were followed up for a mean period ± SD of 10.9 ± 1.4 years. All incidental CT abnormalities were associated with all-cause mortality in univariable analysis (p < 0.05). However, multivariable analysis further revealed fibrotic ILA as an independent risk factor for all-cause mortality (hazard ratio, 2.52 [95% confidence interval, 1.02-6.22], p = 0.046). ILA were also identified as an independent risk factor for lung cancer or respiratory disease-related deaths. Conclusion: Incidental abnormalities on screening thoracic CT were associated with increased mortality during the long-term follow-up. Among incidental CT abnormalities, fibrotic ILA were independently associated with increased mortality. Appropriate management and surveillance may be required for patients with fibrotic ILA on thoracic CT obtained for general screening purposes.

In vitro Antioxidant Effects of Sarijang (사리장의 항산화 효과)

  • Seo, Bo-Young;Choi, Mi-Joo;Choi, Eun-A;Park, Eunju
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.4
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    • pp.618-623
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    • 2014
  • Sarijang, a soy sauce made from fermented black soybean (Rhynchosia nulubilis), sulfur fed duck, dried bark of Ulmus davidiana, Allium sativum, and bamboo salt, has been demonstrated to exert anti-inflammatory and anti-tumor activities. However, the antioxidant properties of Sarijang have not yet been elucidated. In this study, the antioxidant effects of Sarijang were investigated by determining total phenolic content (TPC), DPPH radical scavenging activity (DPPH RSA), total radical trapping antioxidant potential (TRAP), oxygen radical absorbance capacity (ORAC), and cellular antioxidant capacity (CAC). The inhibitory effects of Sarijang on oxidative stress-induced DNA damage (200 ${\mu}M$ $H_2O_2$, 250 ${\mu}M$ Fe-NTA, and 200 ${\mu}M$ HNE) in human leukocytes were evaluated by comet assay. The TPC of Sarijang was $1.04{\pm}0.01$ mg GAE/mL. DPPH RSA, TRAP, and ORAC values of Sarijang increased in a dose-dependent manner. The $IC_{50}$ for DPPH RSA of Sarijang was $11.2{\pm}0.3$ mg/mL, whereas $IC_{50}$ of TRAP was $209.5{\pm}2.0$ mg/mL. 2,2'-Azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative stress and oxidative stress-induced DNA damage in HepG2 cells were effectively abrogated by all tested concentrations of Sarijang (1~100 ${\mu}g/mL$). These results suggest that Sarijang has antioxidative activity and protective effects against oxidative DNA damage.

Chloride Binding Properties of Portland Cement Binder Incorporating CaAl2O4-CaAl4O7 (CaAl2O4-CaAl4O7 혼입 포틀랜드 시멘트 결합재의 염소이온 고정 특성)

  • Han, Jae-Doh;Lee, Yun-Su;Lee, Han-Seung
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.24 no.4
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    • pp.1-9
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    • 2020
  • This study conducted to understand effects of CA (CaAl2O4) and CA2 (CaAl4O7) ratio on chloride binding ability and compressive strength and pore structure of cement mortar incorporating mixture of CA and CA2. The Portland cement based specimens were mixed with the clinkers CA and CA2, and these calcium aluminate clinker mixture were replaced 0, 5, 10% by weight of cement. After all the test specimens were cured for 28 days under water curing, they were immersed in the distilled water and NaCl solution. As a result, 28 days compressive strength of all specimens was similar, and As the replacement ratio of calcium aluminate clinker in the specimen increased, Friedel's salt production tended to increase. However, it was dependent on the amount of Al2O3 in the level of 5% replacement and CA ratio in the level of 10% replacement. Through equilibrium isotherm result, it was also indicated that as replacement ratio of calcium aluminate clinker in cement matrix increased, chloride binding capacity was improved, and chloride penetration was suppressed. In this study, the specimen replaced with 10% of the calcium aluminate clinker mixture (CA 39%, CA2 60%) was remarkable to control chloride attack. We figured out necessity to understand optimal CA/CA2 ratio to effectively apply CA2 as a sustainable building material by improving the chloride binding ability in Portland cement based system.

Evaluation of Metal-Amino Acid Chelates and Complexes at Various Levels of Copper and Zinc in Weanling Pigs and Broiler Chicks

  • Lee, S.H.;Choi, S.C.;Chae, B.J.;Lee, J.K.;Acda, S.P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.12
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    • pp.1734-1740
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    • 2001
  • Feeding trials using weanling pigs and broiler chicks were conducted to evaluate the efficacy of different metal-amino acid chelates and complexes at various levels of copper and zinc on the performance and fecal excretions. A total of 200 weanling pigs (Large White ${\times}$ Yorkshire ${\times}$ Duroc, $11.20{\pm}0.81kg$) were randomly assigned to 5 dietary treatments following a randomized complete block design. Each treatment was replicated 4 times with 10 pigs per pen. The dietary treatments were designated as : A-diet containing 170 ppm Cu from $CuSO_4$ and 120 ppm Zn from $ZnSO_4$, B-diet containing 85 ppm Cu from Cu-amino acid chelate (CAC) and 60 ppm Zn from Zn-amino acid chelate (ZAC), C-diet containing 170 ppm Cu from CAC and 120 ppm Zn from ZAC, D-diet containing 85 ppm Cu from Cu-lysine complex (CL) and 60 ppm Zn from Zn-methionine complex (ZM), and E-diet containing 170 ppm Cu from CL and 120 ppm Zn from ZM. On the other trial, 144 of one day old broiler chicks were randomly distributed to 6 dietary treatments following a completely randomized design. Each treatment was replicated 3 times with 8 chicks per replicate. The dietary treatments were as follows: 1-diet with 60 ppm Cu from $CuSO_4$ and 40 ppm Zn from $ZnSO_4$, 2-diet with 120 ppm Cu from $CuSO_4$ and 80 ppm Zn from $ZnSO_4$, 3-diet with 60 ppm Cu from CAC and 40 ppm Zn from ZAC, 4-diet with 120 ppm Cu from CAC and 80 ppm Zn from ZAC, 5-diet with 60 ppm Cu from CL and 40 ppm Zn from ZM, and 6-diet with 120 ppm Cu from CL and 80 ppm Zn from ZM. In Exp. 1 with pigs, there was no difference on average daily gain and average daily feed intake observed among treatments. There was improvement (p<0.05) on the overall feed conversion ratio (FCR) of pigs fed diet containing 120 ppm Zn and 170 ppm Cu from metal-amino acid chelates relative to those fed diet containing inorganic sources of Cu and Zn but equally efficient as those fed diet containing metal-amino acid complexes. Pigs fed diet containing either metal-amino acid chelates or complexes as sources of Cu and Zn had higher (p<0.05) Cu and Zn concentration in serum and lower (p<0.05) in feces than those receiving diet with inorganic sources. In Exp. 2 with broiler chicks, the overall FCR was not different among treatments. Higher (p<0.05) Cu and Zn concentration in serum was obtained from birds fed diet with 60 ppm Cu and 40 ppm Zn from metal-amino acid chelates compared to those fed diet with inorganic sources of Cu and Zn. Also, the feces collected from birds fed diet with either metal-amino acid chelates or complexes contained generally lower Cu and Zn than those birds fed diet with inorganic sources. The higher the dietary level of Cu and Zn the higher the Cu and Zn concentration in the feces. Based on the results, both metal-amino acid chelates and complexes of Cu and Zn at low levels (Zn 60 ppm, Cu 85 ppm for weanling pigs and Zn 40 ppm, Cu 60 ppm for broiler chicks) are not different from that of high levels of inorganic sources in maintaining growth performance and serum concentration. The fecal excretions for Cu and Zn were greatly reduced when organic sources were used.

Dynamic bending response of SWCNT reinforced composite plates subjected to hygro-thermo-mechanical loading

  • Chavan, Shivaji G.;Lal, Achchhe
    • Computers and Concrete
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    • v.20 no.2
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    • pp.229-246
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    • 2017
  • The dynamic bending response of single walled carbon nanotube reinforced composite (SWCNTRC) plates subjected to hygro-thermo-mechanical loading are investigated in this paper. The mechanical load is considered as wind pressure for dynamic bending responses of SWCNTRC plate. The dynamic version of the High Order shear deformation Theory (HSDT) for a composite plate with Matrix and SWCNTRC plate is first formulated. Distribution of fibers through the thickness of the SWCNTRC plate could be uniform or functionally graded (FG). The dynamic displacement response is predicted by using Nemarck integration method. The effective material properties of SWCNTRC are estimated by using micromechanics based modeling approach. The effect of different environmental condition, volume fraction of SWCNT, Width-to-thickness ratio, wind pressure, different SWCNTRC-FG plates, boundary condition, E1/E2 ratio, different temperature on dynamic displacement response is investigated. The dynamic displacement response is compared with the available literature and it shows good agreement.

Modeling the alkali aggregate reaction expansion in concrete

  • Zahira, Sekrane Nawal;Aissa, Asroun
    • Computers and Concrete
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    • v.16 no.1
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    • pp.37-48
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    • 2015
  • Alkali aggregate reaction affects numerous civil engineering structures and causes irreversible expansion and cracking. This work aims at developing model to predict the potential expansion of concrete containing alkali-reactive aggregates. First, the paper presents the experimental results concerning the influence of particle size of an alkali-reactive aggregate on mortar expansion studied at 0.15-0.80 mm, 1.25-2.50 mm and 2.5-5.0 mm size fractions and gives data necessary for model development. Results show that no expansion was measured on the mortars using small particles (0.15-0.80 mm) while the particles (1.25-2.50 mm) gave the largest expansions. Finally, model is proposed to simulate the experimental results by studying correlations between the measured expansions and the size of aggregates and to calculate the thickness of the porous zone necessary to take again all the volume of the gel created by this chemical reaction.

Deformation-based Strut-and-Tie Model for reinforced concrete columns subject to lateral loading

  • Hong, Sung-Gul;Lee, Soo-Gon;Hong, Seongwon;Kang, Thomas H.K.
    • Computers and Concrete
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    • v.17 no.2
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    • pp.157-172
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    • 2016
  • This paper presents a Strut-and-Tie Model for reinforced concrete (RC) columns subject to lateral loading. The proposed model is based on the loading path for the post-yield state, and the geometries of struts and tie are determined by the stress field of post-yield state. The analysis procedure of the Strut-and-Tie Model is that 1) the shear force and displacement at the initial yield state are calculated and 2) the relationship between the additional shear force and the deformation is determined by modifying the geometry of the longitudinal strut until the ultimate limit state. To validate the developed model, the ultimate strength and associated deformation obtained by experimental results are compared with the values predicted by the model. Good agreements between the proposed model and the experimental data are observed.

Analytical simulation of reversed cyclic lateral behaviors of an RC shear wall sub-assemblage

  • Lee, Han Seon;Jeong, Da Hun;Hwang, Kyung Ran
    • Computers and Concrete
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    • v.10 no.2
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    • pp.173-196
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    • 2012
  • Experimental results of cyclic reversed lateral force test on a two-story reinforced concrete shear wall sub-assemblage are simulated analytically by using the PERFORM-3D program. A comparison of experimental and analytical results leads to the following conclusions: (1) "Shear Wall" and "General Wall" models with "Concrete shear" cannot simulate the pinching phenomena due to shear and show larger amounts of inelastic energy absorption than those in the experiment. (2) Modeling a story-height wall by using two or more "General Wall" elements with "Diagonal shear" in the vertical direction induces the phenomenon of swelling-out at the belly, leading to the erroneous simulation of shear behaviors. In application to tall building structures, it is recommended to use one element of "General Wall" with "Diagonal shear" for the full height of a story. (3) In the plastic hinge area, concrete deformations of analytical models overestimate elongation and underestimate shortening when compared with experimental results.

Modeling of sulfate ionic diffusion in porous cement based composites: effect of capillary size change

  • Gospodinov, Peter N.
    • Computers and Concrete
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    • v.4 no.2
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    • pp.157-166
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    • 2007
  • The paper considers a theoretical model to study sulfate ion diffusion in saturated porous media - cement based mineral composites, accounting for simultaneous effects, such as filling micro-capillaries (pores) with ions and chemical products and liquid push out of them. Pore volume change and its effect on the distribution of ion concentration within the specimen are investigated. Relations for the distribution of the capillary relative radius and volume within the composite under consideration are found. The numerical algorithm used is further completed to consider capillary size change and the effects accompanying sulfate ion diffusion. Ion distribution within the cross section and volume of specimens fabricated from mineral composites is numerically studied, accounting for the change of material capillary size and volume. Characteristic cases of 2D and 3D diffusion are analyzed. The results found can be used to both assess the sulfate corrosion in saturated systems and predict changes occurring in the pore structure of the composite as a result of sulfate ion diffusion.