• Title/Summary/Keyword: Michael Addition

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An Evaluation of the Accuracy of Maximum Likelihood Procedure for Estimating HIV Infectivity

  • Um, Yonghwan;Haber, Michael-J
    • Communications for Statistical Applications and Methods
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    • v.6 no.3
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    • pp.957-966
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    • 1999
  • We evaluate the accuacy and precision of maximum likelihood estimation procedures for infectivity of HIV in partner studies. This is achieved by applying the oricedyre typothetical samples generated by computer. One hundred samples were generated with various combinations of parameters. The estimation procedure was found to be quite accurate. in addition it was found that the power of the test for equality of infectivities for two types of contact depends on sample size and length of observation period but not on the number of observations made on each subject. Tests based on a model for the infectivity had higher power than standard methods for comparing proportions.

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AKARI/IRC spectroscopic survey for interstellar ice study

  • Kim, Jaeyeong;Lee, Jeong-Eun;Kim, Il-Seok;Aikawa, Yuri;Jeong, Woong-Seob;Lee, Ho-Gyu;Noble, Jennifer A.;Dunham, Michael M.
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.41.3-41.3
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    • 2019
  • Ices in interstellar environments are well traced mostly by their absorption features in the near- to mid-infrared spectrum. The infrared camera (IRC) aboard AKARI provides us the near-infrared spectroscopic data which cover $2.5-5.0{\mu}m$ with a spectral resolution of R ~ 120. Our AKARI spectroscopic survey of young stellar objects (YSOs), including low-luminosity protostars and background stars, revealed the absorption features of $H_2O$, $CO_2$, CO, and XCN ice components. We present near-infrared spectra of the observed targets and compare their ice abundances with those previously derived from various YSOs and the background stars behind dense molecular clouds and cores. In addition, we suggest possible science cases for SPHEREx, NASA's new near-infrared space observatory, based on the results from our AKARI IRC spectroscopic study.

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Applications of Solid Viscoelastic Coupling Dampers (VCDs) in Wind and Earthquake Sensitive Tall Buildings

  • Montgomery, Michael;Ardila, Luis;Christopoulos, Constantin
    • International Journal of High-Rise Buildings
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    • v.10 no.2
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    • pp.123-135
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    • 2021
  • Solid Viscoelastic Coupling Dampers (VCDs) provide distributed damping that improves the dynamic performance of tall buildings for both wind-storms and earthquakes for all amplitudes of vibration. They are configured in place of typical structural members in tall buildings and therefore do not occupy any architectural space. This paper summarizes the research and development at the University of Toronto in collaboration with Nippon Steel Engineering, 3M and Kinetica over the past two decades. In addition, impact studies on buildings incorporating the VCDs are presented, consisting of a wind sensitive 66-story building in Toronto, a dual-wind and seismic performance-based design of a 4-tower development in Manila and finally a 630 meter Megatall building in Southeast Asia in a severe seismic environment. In all applications the VCDs are shown to provide significant benefits in the dynamic performance under both wind and earthquake loading in a cost-effective manner.

eSports Fan Identity Consumer and Live Game Watching Behavior: Professional Player Fan Identity Perspective

  • Jialing Zhang;C. Michael Hall;Myung Ja Kim
    • Journal of Smart Tourism
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    • v.3 no.1
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    • pp.9-21
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    • 2023
  • This study investigated whether the Point of attachment (POA) theory can be used to measure the consumption intention on go and watch offline eSports games. The admiration for players, social interaction, and on-site consumption requirements for viewing offline eSports competitions are prioritized. In addition, eSports fans in various regions may have distinct consumption concepts and consumption patterns. Thus, this study surveyed China (n = 156) and South Korea (n = 127) eSports fans who subjectively perceive themselves to be fans of eSports player(s) and who have observed at least one offline eSports game. The results demonstrate that player attraction and socialization have positive and significant effects on offline consumption factors. There is no correlation between previous consumption behavior and satisfaction, but dining shows a significant positive effect on satisfaction. Moreover, there is a strong relationship between satisfaction and future attendance intention. In addition, effect of eSports fan attachment on future visit intentions are measured and there is no correlation between the two variables. The front end of the path in the new model's varied between Chinese and Korean supporters. Finally, theoretical and practical implications of this study are discussed.

Preparation of Poly(imide-aramid-sulfone)s and their Thermal Properties (폴리(이미드-아라미드-설폰)의 합성과 그들의 열적성질)

  • Park, Hyung-Seok;Gong, Myoung-Seon
    • Polymer(Korea)
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    • v.36 no.4
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    • pp.427-433
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    • 2012
  • A series of poly(imide-aramid-sulfone)s with alternatingly introduced imide/aramid groups were prepared by reacting divinyl sulfone (DVS) and $N^1,N^4$-bis(4-(vinylsulfonyl)phenyl)terephthalamide (2) with pyromellitic diimide. Three model compounds, N-[2-(p-aminophnenylsulfonyl)ethyl]phthalimide (3), 2,2'-(2,2'-sulfonylbis(ethane-2,1-diyl))diisoindoline-1,3-dione (4), and N,N-bis(4-(2-(1,3-dioxoisoindolin-2-yl)ethylsulfonyl)phenyl)terephthalamide (5), resembling polymers were prepared with good yields by reacting p-aminophenyl vinyl sulfone, DVS, and 2 with phthalimide. Condensation polymerization was carried out by Michael-type addition reaction of the difunctional phthalimide group with the DVS group in the presence of tetrabutylammonium hydroxide (TBAH), resulting in poly(imide-aramid-sulfone)s 6-12 with moderate molecular weights and good yields. They were highly soluble in polar solvents such as N,N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidinone and tetrahydrofuran. The ratios of DVS/2 were 1/0, 3/1, 2/1, 1/1, 1/2, 1/3, and 0/1. Molecular weight and physical properties such as solubility, viscosity, and thermal properties of the polymers were examined.

Biguanide-Functionalized Fe3O4/SiO2 Magnetic Nanoparticles: An Efficient Heterogeneous Organosuperbase Catalyst for Various Organic Transformations in Aqueous Media

  • Alizadeh, Abdolhamid;Khodaei, Mohammad M.;Beygzadeh, Mojtaba;Kordestani, Davood;Feyzi, Mostafa
    • Bulletin of the Korean Chemical Society
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    • v.33 no.8
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    • pp.2546-2552
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    • 2012
  • A novel biguanide-functionalized $Fe_3O_4/SiO_2$ magnetite nanoparticle with a core-shell structure was developed for utilization as a heterogeneous organosuperbase in chemical transformations. The structural, surface, and magnetic characteristics of the nanosized catalyst were investigated by various techniques such as transmission electron microscopy (TEM), powder X-ray diffraction (XRD), vibrating sample magnetometry (VSM), elemental analyzer (EA), thermogravimetric analysis (TGA), $N_2$ adsorption-desorption (BET and BJH) and FT-IR. The biguanide-functionalized $Fe_3O_4/SiO_2$ nanoparticles showed a superpara-magnetic property with a saturation magnetization value of 46.7 emu/g, indicating great potential for application in magnetically separation technologies. In application point of view, the prepared catalyst was found to act as an efficient recoverable nanocatalyst in nitroaldol and domino Knoevenagel condensation/Michael addition/cyclization reactions in aqueous media under mild condition. Additionally, the catalyst was reused six times without significant degradation in catalytic activity and performance.

The Role of Thymic Stromal Lymphopoietin (TSLP) in Glomerulonephritis

  • Lee, Keum Hwa;Yang, Jae Won;Cho, Jin Young;Lee, Joo Yup;Lim, Eun Kyung;Eisenhut, Michael;Jeong, Dong Yeon;Steingroever, Johanna;Shin, Jae Il
    • Childhood Kidney Diseases
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    • v.22 no.1
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    • pp.17-21
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    • 2018
  • Thymic stromal lymphopoietin (TSLP) is an interleukin-7-like cytokine that is an important trigger and initiator of many allergic diseases. TSLP promotes a T-helper type 2 (Th2) cytokine response that can be pathological. A relationship is formed both at the induction phase of the Th2 response through polarization of dendritic cells to drive Th2 cell differentiation and at the effector phase of the response, by promoting the expansion of activated T cells and their secretion of Th2 cytokines and TSLP. In transgenic mice with TSLP overexpression, it has been reported that TSLP leads to the development of mixed cryoglobulinemic membranoproliferative glomerulonephritis. In addition, TSLP can play an important role in the pathogenesis of IgA nephropathy and systemic lupus erythematosus-related nephritis. From our knowledge of the role of TSLP in the kidney, further studies including the discovery of new therapies need to be considered based on the relationship between TSLP and glomerulonephritis.

Production of superoxide anion, nitric oxide and tumor necrosis factor-$\alpha$ by cultured murine peritoneal leukocytes is inhibited by taurine chloramine

  • Kim, Chaekyun;Park, Eunkyue;Michael R. Quinn
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.04a
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    • pp.177-177
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    • 1996
  • Taurine Chloramine (Tau-Cl) inhibits production of nitric oxide(NO) and tumor necrosis factor-alpha (TNF-${\alpha}$) in activated peritoneal macrophages, similar In that previously reported for activated RAW 264.7 cells. In addition, the effect of Tau-Cl and taurine on superoxide anion (O$\_$2/$\^$-/) Production in murine peritoneal exudate polymorphonuclear leukocytes (PMN) was examined. Tau-Cl inhibited O$\_$2/$\^$-/ production in a manner that was dose-dependent and reversible, Taurine also inhibited O$\_$2/$\^$-/ production by stimulated PMN, but at higher concentrations and to a lesser extent than Tau-Cl. The effects of taurine on O$\_$2/$\^$-/ production was attributed to the in vitro formation of Tau-Cl catalyzed by PMN associated halide-dependent myeloperoxidase. In contrast, production of NO and TNF-${\alpha}$ by activated peritoneal exudate macrophages was inhibited by Tau-Cl while taurine was without effect. These data lend support to the notion that Tau-Cl may participate ill the inflammatory responses by modulating production of inflammatory mediators.

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The Creativity in Decoration Designs with Coptic symbols

  • Michael, Vivian Shaker
    • International Journal of Human Ecology
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    • v.12 no.1
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    • pp.101-113
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    • 2011
  • This research aims to enrich the field of decorative designs for the T-shirts of youth clothes. Youth T-shirts have been chosen because they are essential apparel and one of the most important casualwear. T-shirts are probably the number one item sold across the world. Every tourist shop has many of them, worldwide. The decorative ideas have been inspired from some symbols of Coptic arts. This incorporates the cultural power of Coptic art as a vital starting point for new design ideas and development of products. However, the purpose of this research is to make our youth know something about the Coptic arts of Egypt, as a part of their history, and on the other hand for tourists as well. Youth are very suitable tools for spreading our new ideas where they are energetic and full of life. In this work, twenty-one designs are presented inspired from ten Coptic symbols. Five designs have been implemented in three different ways of printing and embroidery, i.e. there are fifteen models have been formed. An opinion poll has been occurred for two groups of youth, one is younger and the other is older, hence T-test has been applied. It is clarified that our designs are approved by the younger group than the older one. The results of this work can offer some good reasons for further investigations on the fashionable decorated designs for youth and tourists as well; in addition to the decoration education development.

Predictive Current Control for Multilevel Cascaded H-Bridge Inverters Based on a Deadbeat Solution

  • Qi, Chen;Tu, Pengfei;Wang, Peng;Zagrodnik, Michael
    • Journal of Power Electronics
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    • v.17 no.1
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    • pp.76-87
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    • 2017
  • Finite-set predictive current control (FS-PCC) is advantageous for power converters due to its high dynamic performance and has received increasing interest in multilevel inverters. Among multilevel inverter topologies, the cascaded H-bridge (CHB) inverter is popular and mature in the industry. However, a main drawback of FS-PCC is its large computational burden, especially for the application of CHB inverters. In this paper, an FS-PCC method based on a deadbeat solution for three-phase zero-common-mode-voltage CHB inverters is proposed. In the proposed method, an inverse model of the load is utilized to calculate the reference voltage based on the reference current. In addition, a cost function is directly expressed in the terms of the voltage errors. An optimal control actuation is selected by minimizing the cost function. In the proposed method, only three instead of all of the control actuations are used for the calculations in one sampling period. This leads to a significant reduction in computations. The proposed method is tested on a three-phase 5-level CHB inverter. Simulation and experimental results show a very similar and comparable control performance from the proposed method compared with the traditional FS-PCC method which evaluates the cost function for all of the control actuations.