• Bulletin of the Korean Chemical Society
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• v.7 no.1
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• pp.25-29
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• 1986

The reaction of cysteine with cinnamaldehyde have been studied kinetically and thermodynamically. It was found that the reaction proceeds in two steps; formation of the monoadduct by a Michael type addition followed by the nucleophilic attack of the second cysteine to the carbonyl carbon of the monoadduct to afford the thiazolidine derivative. A reaction profile for the reaction of cysteine with cinnamaldehyde was constructed based on the thermodynamic parameters analyzed for the forward and the reverse reactions. It was assumed that the second step of this reaction accompanies an intermediate, a Schiff base.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.90-94
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• 2012

The furan-2-ylidene acetates (3a-d), obtained from the furan-2,3-diones (1a-b) and methyl/ethyl (triphenylphosphoranylidene)-acetates (2a-b), were converted via the Michael type reactions with 2,3-diaminopyridine and its derivatives (4a-c) into the corresponding pyrrol-2-ylidene-acetates (5a-j) in moderate yields (45-94%). Structures of these compounds were determined by the IR, NMR, elemental analysis, and X-ray diffraction method.

• Clinical and Experimental Vaccine Research
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• v.12 no.1
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• pp.60-69
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• 2023

Purpose: Although the fast development of safe and effective messenger RNA (mRNA) vaccines against severe acute respiratory syndrome coronavirus 2 has been a success, waning humoral immunity has led to the recommendation of booster immunization. However, knowledge of the humoral immune response to different booster strategies and the association with adverse reactions is limited. Materials and Methods: We investigated adverse reactions and anti-spike protein immunoglobulin G (IgG) concentrations among health care workers who received primary immunization with mRNA-1273 and booster immunization with mRNA-1273 or BNT162b2. Results: Adverse reactions were reported by 85.1% after the first dose, 94.7% after the second dose, 87.5% after a third dose of BNT162b2, and 86.0% after a third dose of mRNA-1273. They lasted for a median of 1.8, 2.0, 2.5, and 1.8 days, respectively; 6.4%, 43.6%, and 21.0% of the participants were unable to work after the first, second, and third vaccination, respectively, which should be considered when scheduling vaccinations among essential workers. Booster immunization induced a 13.75-fold (interquartile range, 9.30-24.47) increase of anti-spike protein IgG concentrations with significantly higher concentrations after homologous compared to heterologous vaccination. We found an association between fever, chills, and arthralgia after the second vaccination and anti-spike protein IgG concentrations indicating a linkage between adverse reactions, inflammation, and humoral immune response. Conclusion: Further investigations should focus on the possible advantages of homologous and heterologous booster vaccinations and their capability of stimulating memory B-cells. Additionally, understanding inflammatory processes induced by mRNA vaccines might help to improve reactogenicity while maintaining immunogenicity and efficacy.

• Biomaterials Research
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• v.22 no.4
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• pp.235-248
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• 2018

Background: Injectable hydrogels have been extensively researched for the use as scaffolds or as carriers of therapeutic agents such as drugs, cells, proteins, and bioactive molecules in the treatment of diseases and cancers and the repair and regeneration of tissues. It is because they have the injectability with minimal invasiveness and usability for irregularly shaped sites, in addition to typical advantages of conventional hydrogels such as biocompatibility, permeability to oxygen and nutrient, properties similar to the characteristics of the native extracellular matrix, and porous structure allowing therapeutic agents to be loaded. Main body: In this article, recent studies of injectable hydrogel systems applicable for therapeutic agent delivery, disease/cancer therapy, and tissue engineering have reviewed in terms of the various factors physically and chemically contributing to sol-gel transition via which gels have been formed. The various factors are as follows: several different non-covalent interactions resulting in physical crosslinking (the electrostatic interactions (e.g., the ionic and hydrogen bonds), hydrophobic interactions, ${\pi}$-interactions, and van der Waals forces), in-situ chemical reactions inducing chemical crosslinking (the Diels Alder click reactions, Michael reactions, Schiff base reactions, or enzyme-or photo-mediated reactions), and external stimuli (temperatures, pHs, lights, electric/magnetic fields, ultrasounds, or biomolecular species (e.g., enzyme)). Finally, their applications with accompanying therapeutic agents and notable properties used were reviewed as well. Conclusion: Injectable hydrogels, of which network morphology and properties could be tuned, have shown to control the load and release of therapeutic agents, consequently producing significant therapeutic efficacy. Accordingly, they are believed to be successful and promising biomaterials as scaffolds and carriers of therapeutic agents for disease and cancer therapy and tissue engineering.

• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.120-126
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• 1989

The Kinetics of hydrolysis of styrylphenylsulfone derivatives in 50% methanol-water at 25$^{\circ}$C and ionic strength of 0.10 was investigated by UV spectrophotometry in the pH range of 0.0-14.0. The rate equations, which can be applied over a wide pH range, were obtained. The Hammett rho constants for the hydrolysis are 1.85 at pH 7.0 and 1.54 at pH 13.0, respectively. On the basis of the evidence, it is proposed that the general base-catalysis occurs in the hydrolysis of styrylphenylsulfone derivatives; above pH 11.0, Michael type nucleophilic addition take place, while below pH 9.0, the reaction is initiated by addition of water and from pH 9.0 to pH 11.0 these two reactions occur com-petitively.

• English & American cultural studies
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• v.13 no.1
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• pp.29-57
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• 2013

Patricia Waugh once regarded modernism fiction as 'the struggle for personal autonomy' against the opposition existing social institutions and conventions. Michael Cunningham's characterizations of Virginia Woolf and Septimus in The Hours show the two contrasting reactions to individual alienation and mental dissolution in the modern era. As the personifications of endurance and self-destruction against the mechanical power of contemporary world, Woolf and Septimus consist of just the world of diptych where the woman's role is confined to the angel in the house. By creating Mrs. Brown based upon his own alienated mother image, however, Cunningham succeeds in representing the more dramatically vivid world of triptych where woman can have her own room and self-realization despite still facing the dilemma of the traditional family. Accepting Joycean Bloom's optimistic and relaxing way of life in part, Mrs. Brown connects the labyrinths between the author's (and also Richard's) alienation with the theme of celebration of the life. Clarissa in postmodern New York setting is still a concealed and mystified character. Similar to Mrs. Dalloway, on the one hand Clarissa watches other people's tragedy with compassion. Cunningham's Clarissa, on the other hand, is no longer seeking for either winning or defeat in the spectacular world unlike her predecessors. In many resilient attitudes of everyday life Clarissa is closest to Mrs. Brown whom Virginia Woolf originally hopes to describe. Without any fear or rage toward the society Clarissa witnesses and achieves "the humanity, humour, depth" of female values by successfully turning the trivial life into an epic journey.

• Journal of the Korean Chemical Society
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• v.40 no.8
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• pp.571-578
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• 1996

Iron alkynyl(amino)carbene complexes, (${\beta}$-aminovinyl)carbene complexes, ${\eta}^3$-(2-(alkylcarbonyl)vinyl)carbene complexes, and a 3-aminoallenylidene complex were formed in the reactions of iron alkynyl(ethoxy)carbene complexes with amines. The ratio of the products, which were formed by substitution reaction, the Michael addition of amines, rearrangements after the addition reaction, and the addition followed by the elimination of the ethoxy group, respectively, was dependent on reaction temperature, the substituent of the alkynyl moiety, and employed amines.

• Rapid Communication in Photoscience
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• v.2 no.3
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• pp.68-71
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• 2013

Acetone sensitized photoadditions of isopropanol to (5R)-5-menthyloxy-2-(5H)-furanone were investigated in two different microflow reactor systems. Setup A employed a commercially available glass reactor under a UVB-panel. Setup B utilized a FEP microcapillary wrapped tightly around a Pyrex cylinder with a single UVB fluorescent tube at its center. The reactions under flow conditions were subsequently compared to analogue reactions conducted in a batch chamber reactor. Overall, the microflow systems gave faster conversions and higher isolated yields. The flexible microcapillary setup, however, showed the best performance and promise in terms of future scale-up and reactor optimization.

• Archives of Pharmacal Research
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• v.12 no.3
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• pp.201-206
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• 1989

The reaction of acetoacetanilide (1) with the $\alpha$-cyanocinnamonitrile derivatives 2 yielded the Michael adducts 4 which could be converted into the pyrano [2, 3, -c] pyrazole derivatives 5 via their reaction with hydrazine hydrate. Cyclisation of 4 afforded the derivatives 10. The pyranopyrazoles 9 reacted with different activated nitrile derivatives (3a-c) to give the pyrano [2, 3-c] pyridine derivatives 13. 16 and 19 respectively. The biological activity of the synthesised heterocyclic derivatives was investigated and discussed.

• Nuclear Engineering and Technology
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• v.49 no.6
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• pp.1199-1210
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• 2017

A new in-line method for sampling neutrons emitted in (${\alpha}$,n) reactions based on alpha particle source information has been developed for continuous-energy Monte Carlo simulations. The new method uses a continuous-slowing-down model coupled with (${\alpha}$,n) cross section data to precompute the expected neutron yield over the alpha particle lifetime. This eliminates the complexity and computational cost associated with explicit charged particle transport. When combined with an integrated alpha particle decay source sampling capability, the proposed method provides an efficient and accurate method for sampling (${\alpha}$,n) neutrons based solely on nuclide inventories in the problem, with no additional user input required. Results from several example calculations show that the proposed method reproduces the (${\alpha}$,n) neutron yields and energy spectra from reference experiments and calculations.