• Rapid Communication in Photoscience
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• 제4권1호
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• pp.1-8
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• 2015

For understanding molecular mechanisms of photochemical reactions, in particular reactions of proteins with biological functions, it is important to elucidate both the initial reactions from the photoexcited states and the series of subsequent chemical reactions, e.g., conformation, intermolecular interactions (hydrogen bonding, hydrophobic interactions), and inter-protein interactions (oligomer formation, dissociation reactions). Although time-resolved detection of such dynamics is essential, these dynamics have been very difficult to track by traditional spectroscopic techniques. Here, relatively new approaches for probing the dynamics of protein photochemical reactions using time-resolved transient grating (TG) are reviewed. By using this method, a variety of spectrally silent dynamics can be detected and such data provide a valuable description about the reaction scheme. Herein, a blue light sensor protein TePixD is the exemplar. The initial photochemistry for TePixD occurs around the chromophore and is detected readily by light absorption, but subsequent reactions are spectrally silent. The TG experiments revealed conformational changes and changes in inter-protein interactions, which are essential for TePixD function. The TG experiments also showed the importance of fluctuations of the intermediates as the driving force of the reaction. This technique is complementary to optical absorption detection methods. The TG signal contains a variety of unique information, which is difficult to obtain by other methods. The advantages and methods for signal analyses are described in detail in this review.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.5-7
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• 2014

A skeletal mechanism of coal combustion was derived from a detailed coal combustion kinetic mechanism through an importance analysis of chemical pathways. The reduction process consists of roughly two parts. The first process is performed based on a connectivity analysis between species. In this process, DRGEPSA is chosen for reduction process. Strongly connected species and related reactions from the important species set as start species by the operator are sorted into the reduced mechanism. About 70% of species and reactions can be removed with a limited accuracy loss. Subsequently the second reduction process, CSP, is performed. This method focuses on an importance of each reaction and can reduce a volume of mechanism appropriately. Through these analyses, a skeletal mechanism is generated that is including 65 species and 150 reactions. The generated skeletal mechanism is verified through a comparison with the detailed mechanism in the homogeneous reactor model of CHEMKIN-PRO under wide range of conditions. The generated mechanism can give an advantage in the analysis of coal combustion characteristics in detail in large scale simulations such as LES and DNS.

• Journal of Dental Anesthesia and Pain Medicine
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• 제23권3호
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• pp.173-177
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• 2023

Local anesthetics are an essential part of pain control during dental treatment. Despite its effectiveness and safety, patients should constantly be aware of potential adverse effects, including allergic reactions. Allergic reactions to amide-type local anesthetics (LAs), such as lidocaine and mepivacaine, are rare compared to those to ester-type LAs. Herein, we report the case of a patient with a history of allergy to lidocaine and mepivacaine, with symptoms of itching, diffuse erythema of the wrists and hands, dizziness, and pectoralgia. This case report emphasizes the importance of collecting medical and dental histories of patients is necessary, and how an allergy test in the allergy and clinical immunology department helps select safe LAs for patients.

• Journal of the Korean Chemical Society
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• 제31권2호
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• pp.133-142
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• 1987

Stereoselectivities of (4+2) cycloaddition reactions of cyclopentadiene with the methyl-substituted allenic acids and esters were investigated by application of $\pi$-nonbonded interaction ($\pi$-NBI) theory. 2-FMO method has been found to be adequate for determination of endo selectivities of diene(LUMO)-dienophile (LUMO) interaction in the thermal reactions and diene (HOMO)-dienophile (LUMO) interaction in the Lewis acid catalyzed reactions. $\pi$-isoconjugate diene structure was formed by through-bond interaction of allene moiety with methyl group in the cumulated diene system; the methyl substituent acts as a conjugative chain and causes inter-level narrowing effect of the FMO's. In dienophiles which do not form $\pi$-isoconjugate diene system, methyl group acts merely as an electron donating group. In thermal reactions, the stereoselectivities are controlled by $\pi$-nonbonded secondary orbital interaction ($\pi$-NSOI) of methyl substituent, which behaves similarly as an ethylene molecule.

• Journal of Advanced Marine Engineering and Technology
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• 제22권1호
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• pp.108-116
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• 1998

In this paper it is investigated the roles of key elementary reactions for NO formation in methane-air one-dimensional premixed flame and counterflow diffusion flame, which were studied numerically by using NO kinetics and $C_{2}$ -chemistry complied by Miller and Bowman. The spatial distributions of the reaction rates of 9 main elementary reactions directly related to NO formation and destruction were calculated. Integration of the rates of all reactions in the NO formation across the flame yields the quantitative reaction path diagram, which shows clearly relative importance of each reaction path in NO formation and how it changes with the type and parameters of the flame. The results show that the thermal and Fenimore mechanisms are dominant respectively for learn and rich premixed flames, and the latter is dominant for diffusion flames. In addition, it was found that the HCN recycle route is important for diffusion flame, and that the routes of mutual transformation between NO and NO$^{2}$, and between NO and HNO do not contribute to the net NO formation.

• Clinical and Experimental Pediatrics
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• 제60권4호
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• pp.99-105
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• 2017

Food allergy (FA) is a serious health problem, and severe FA such as food-induced anaphylaxis can often be life threatening. The incidence of FA has been increasing especially in children. They usually develop early in life and affect up to 10% of children. The 2 most common food allergens worldwide are milk and eggs, while the third one varies depending on the countries: peanuts in the United States and Switzerland, wheat in Germany and Japan, tree nuts in Spain, sesame in Israel, and walnuts in Korea. These common food allergens are different and difficult to identify because of differing study methodologies, population, geography, age, and dietary exposure patterns. The current management of FA relies on the strict avoidance of culprit allergens, the prompt treatment of allergic reactions, including epinephrine use for food-induced anaphylaxis, monitoring, and education to prevent further reactions. Newer approaches for tolerance induction to FA and FA immunotherapy have been under investigation but are not yet ready for real-world application. Thus, consistent and systematic education of patients, caregivers, and food-handling people is of primary importance for the management and prevention of FA reactions. This review assesses and compares IgE-mediated FA in children in Korea and other countries, with a focus on summarizing the prevalence, common triggers, and management of FA.

• Korean Journal of Child Studies
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• 제34권1호
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• pp.103-121
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• 2013

The purpose of this study was to explore Korean mothers' beliefs regarding their toddlers' temperament, including what they believe constitutes desirable and undesirable behavior, and their resulting reactions. Data were collected int the process of interviewing 50 Korean mothers of toddlers (whose average age was 34.1 Months, and of which 54% were boys). Results revealed that mothers considered 'High-Sociality', 'Positive Affect' and 'High-Effortful Control' as desirable temperaments, whereas 'Negative Affect', 'Under-Effortful Control' and 'Low Sociality' were considered to be undesirable temperaments for toddlers. Mothers cited the importance of child 'Sociality' and 'Development', 'Easiness of Parenting' and 'Child Happiness' as the reasons for their beliefs. While, they considered 'Negative Affect', 'Under-Effortful Control' and 'Low Sociality' to be undesirable temperaments, citing 'Sociality', 'Difficulty of Parenting', 'Development' and 'Child Safety' as the reasons. Finally, mothers were more likely to give verbal encouragement or physical encouragement such as hugging, in responding to desirable behavior on the part of their child, whereas they were more likely to give firm inhibition, reasoning or inconsistent reaction to their child's undesirable behavior. Many of the mothers' beliefs varied depending on the child's gender. Results were discussed in relation to cultural perspectives.

• Clinical and Experimental Pediatrics
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• 제64권8호
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• pp.393-399
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• 2021

Food allergies and food-induced anaphylaxis are important health problems. Several cofactors modulating the onset of anaphylaxis have been identified. In the presence of cofactors, allergic reactions may be induced at lower doses of food allergens and/or become severe. Exercise and concomitant infections are well-documented cofactors of anaphylaxis in children. Other factors such as consumption of nonsteroidal anti-inflammatory drugs, alcohol ingestion, and stress have been reported. Cofactors reportedly play a role in approximately 30% of anaphylactic reactions in adults and 14%-18.3% in children. Food-dependent exercise-induced anaphylaxis (FDEIA) is the best-studied model of cofactor-induced anaphylaxis. Wheat-dependent exercise-induced anaphylaxis, the most common FDEIA condition, has been studied the most. The mechanisms of action of cofactors have not yet been fully identified. This review aims to educate clinicians on recent developments in the role of cofactors and highlight the importance of recognizing cofactors in food allergies and food-induced anaphylaxis.

• Bulletin of the Korean Chemical Society
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• 제26권10호
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• pp.1481-1490
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• 2005

Carbon-carbon single bond-forming reaction is the most useful and fundamental reaction in organic synthesis. Most of the basic carbon-carbon single bond-forming reactions, thus, developed in the past. In these respects, conceptually new C-C bond formation reaction can be highlighted. The Baylis-Hillman reaction was found at the early 1970’s. However, extensive studies on this highly potential reaction were started only before 15 years. This review has been written to shed more lights to the importance of Baylis-Hillman reaction. We have focused mainly on the reaction mechanism, conceptually related reactions, and chemical transformations of the Baylis-Hillman adducts.

• Journal of Korean Society for Atmospheric Environment
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• 제19권4호
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• pp.451-465
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• 2003

The major conversion processes of SO$_2$ to sulfate are reactions in gaseous, aqueous phase and on dust surface. Using the measurement data in Ganghwa, the background area of metropolitan Seoul Area, the relative contiribution of the conversion processes are estimated. Generally, aqueous cloud if the most important conversion path followed by dust surface, gas, and aqueous aerosol. Importance of conversion on dust surface increases for the dust storm period. The total conversion rate values over the metropolitan Seoul area are between 1.5 and 8.8$\times$10$^{-11}$ mole m$^{-3}$ air.