• Title/Summary/Keyword: Cross reactions

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Etiology of Delayed Inflammatory Reaction Induced by Hyaluronic Acid Filler

  • Won Lee;Sabrina Shah-Desai;Nark-Kyoung Rho;Jeongmok Cho
    • Archives of Plastic Surgery
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    • v.51 no.1
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    • pp.20-26
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    • 2024
  • The etiology and pathophysiology of delayed inflammatory reactions caused by hyaluronic acid fillers have not yet been elucidated. Previous studies have suggested that the etiology can be attributed to the hyaluronic acid filler itself, patient's immunological status, infection, and injection technique. Hyaluronic acid fillers are composed of high-molecular weight hyaluronic acids that are chemically cross-linked using substances such as 1,4-butanediol diglycidyl ether (BDDE). The mechanism by which BDDE cross-links the two hyaluronic acid disaccharides is still unclear and it may exist as a fully reacted cross-linker, pendant cross-linker, deactivated cross-linker, and residual cross-linker. The hyaluronic acid filler also contains impurities such as silicone oil and aluminum during the manufacturing process. Impurities can induce a foreign body reaction when the hyaluronic acid filler is injected into the body. Aseptic hyaluronic acid filler injections should be performed while considering the possibility of biofilm formation or delayed inflammatory reaction. Delayed inflammatory reactions tend to occur when patients experience flu-like illnesses; thus, the patient's immunological status plays an important role in delayed inflammatory reactions. Large-bolus hyaluronic acid filler injections can induce foreign body reactions and carry a relatively high risk of granuloma formation.

Concise Synthesis of Flurbiprofen via Palladium-Catalyzed Cross-Coupling Reactions (팔라듐 촉매하 결합반응을 이용한 플루비프로펜의 간결한 합성)

  • Han, Young Taek
    • YAKHAK HOEJI
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    • v.59 no.2
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    • pp.66-69
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    • 2015
  • A concise synthesis of flurbiprofen, a member of the non-steroidal anti-inflammatory 2-arylpropionic acids, has been accomplished. The key feature of this synthesis involves successive palladium-catalyzed cross coupling reactions. In particular, a 2-arylacylate intermediate, which easily converted to the key 2-arylpropionic acid scaffold, was afforded by a versatile palladium-catalyzed cross coupling reaction between diazopropanate and bisphenylboronic acid. This synthetic procedure would facilitate synthesis of the flurbiprofen and anti-inflammatory 2-arylpropionic acid derivatives.

A study on (n, α) reaction cross sections using a new empirical systematic

  • Sema Kucuksucu;Mustafa Yigit
    • Nuclear Engineering and Technology
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    • v.55 no.11
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    • pp.4026-4031
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    • 2023
  • In this article, we report a new empirical formula for quick calculation of cross sections of (n, α) reactions with 14-15 MeV neutrons. Cross sections are analysed in terms of the compound nucleus model. A systematic trend for 14-15 MeV neutrons is found in the variation of (n, α) reaction cross sections with the parameters (N - Z + 1), (En + Q)0.5 and N/Z. The empirical relation between the cross sections and these parameters has been obtained, which give fairly good fits with the experimental data. We have also investigated the odd-even effects on (n, α) cross sections considering binding energy systematic of the shell model. The present formula is very useful in predicting of the (n, α) cross sections, where the measurements are not available as well as in testing new experimental data.

One-Pot Homo- and Cross-Coupling Reactions of Arenediazonium Tosylate Salts for the Synthesis of Biaryls and Polyaryls

  • Vajpayee, Vaishali;Song, Young-Ho;Ahn, Jeong-Soo;Chi, Ki-Whan
    • Bulletin of the Korean Chemical Society
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    • v.32 no.spc8
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    • pp.2970-2972
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    • 2011
  • One-pot homo- and cross-coupling reactions of arenediazonium tosylate salts bearing a halogen group have been exploited for the synthesis of biaryls and polyaryls under mild conditions. $Pd(OAc)_2$ has proven to be an efficient catalyst for the successful dual transformation of diazonium salts into p-quaterphenyl (3).

Food allergy (식품알레르기)

  • Jaechun Lee;Cheol-Woo Kim
    • Journal of Medicine and Life Science
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    • v.19 no.3
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    • pp.90-94
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    • 2022
  • Food allergy is one of the adverse food reactions, which is developed by immunological reactions. Food allergy is increasing in prevalence among children and adults. In the diagnosis, food challenge is confirmative with history and laboratory tests. Avoidance of culprit food is the only preventive method, especially in patients with severe symptoms. In some food allergies, cross-reactivity among allergens should be considered. Latex-fruit/vegetable syndrome and pollen food allergy syndrome are well-understood phenotypes of food allergy related to cross reaction. Red meat allergy is recently described as one of tick-borne diseases. In a rare phenotype of food-dependent exercise-induced anaphylaxis, factors affecting the absorption of food allergen are important in its pathophysiology.

Cross Interaction Constants As a Measure of the Transition State Structure (Part VI). Nucleophilic Substitution Reactions of Benzyl Chlorides with Anilines and Benzylamines

  • Lee, Ik-Choon;Huh, Chul;Koh, Han-Joong;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.9 no.6
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    • pp.376-378
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    • 1988
  • Results of kinetic studies on the reactions of benzyl chlorides with anilines and benzylamines are reported. Analyses of the cross interaction constants relevant to the degree of bond formation, ${\rho}_{XY}$ and ${\lambda}_{XY}$, are carried out. The magnitudes of the two parameters indicated that the degree of bond formation in the transition state is the typical of that expected for an $S_N2$ reaction, but the reactions with benzylamines appear to have a slightly less degree of bond formation compared with the reactions with anilines.

Production cross sections of radionuclides in the proton induced reactions on natural iron with the proton energy of 57 MeV

  • Sung-Chul Yang;Sang Pil Yoon;Tae-Yung Song;Guinyun Kim
    • Nuclear Engineering and Technology
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    • v.56 no.5
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    • pp.1796-1802
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    • 2024
  • The production cross sections of 55,56,57Co, 52gFe, 52g,54Mn, 51Cr, and 48V from the natFe (p,x) reactions were measured using a proton energy of 57 MeV at the Korea Multi-purpose Accelerator Complex (KOMAC) in Gyeongju, Korea. The conventional stacked-foil activation method and offline γ-ray spectroscopy were used to determine the excitation functions of proton induced nuclear reactions on iron. The measured excitation functions were compared with experimental data in literature and theoretical data from the TENDL-2021 library. The present data show generally good agreement with other experimental data, but discrepancies were found between the present data and the excitation functions of the TENDL-2021 library in the investigated energy range, except for 56,57Co and 54Mn.

Validation of the neutron lead transport for fusion applications

  • Schulc, Martin;Kostal, Michal;Novak, Evzen;Czakoj, Tomas;Simon, Jan
    • Nuclear Engineering and Technology
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    • v.54 no.3
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    • pp.959-964
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    • 2022
  • Lead is an important material, both for fusion or fission reactors. The cross sections of natural lead should be validated because lead is a main component of lithium-lead modules suggested for fusion power plants and it directly affects the crucial variable, tritium breeding ratio. The presented study discusses a validation of the lead transport libraries by dint of the activation of carefully selected activation samples. The high emission standard 252Cf neutron source was used as a neutron source for the presented validation experiment. In the irradiation setup, the samples were placed behind 5 and 10 cm of the lead material. Samples were measured using a gamma spectrometry to infer the reaction rate and compared with MCNP6 calculations using ENDF/B-VIII.0 lead cross sections. The experiment used validated IRDFF-II dosimetric reactions to validate lead cross sections, namely 197Au(n, 2n)196Au, 58Ni(n,p)58Co, 93Nb(n, 2n)92mNb, 115In(n,n')115mIn, 115In(n,γ)116mIn, 197Au(n,γ)198Au and 63Cu(n,γ)64Cu reactions. The threshold reactions agree reasonably with calculations; however, the experimental data suggests a higher thermal neutron flux behind lead bricks. The paper also suggests 252Cf isotropic source as a valuable tool for validation of some cross-sections important for fusion applications, i.e. reactions on structural materials, e.g. Cu, Pb, etc.

Theoretical study of cross sections of proton-induced reactions on cobalt

  • Yigit, Mustafa
    • Nuclear Engineering and Technology
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    • v.50 no.3
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    • pp.411-415
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    • 2018
  • Nuclear fusion may be among the strongest sustainable ways to replace fossil fuels because it does not contribute to acid rain or global warming. In this context, activated cobalt materials in corrosion products for fusion energy are significant in determination of dose levels during maintenance after a coolant leak in a nuclear fusion reactor. Therefore, cross-section studies on cobalt material are very important for fusion reactor design. In this article, the excitation functions of some nuclear reaction channels induced by proton particles on $^{59}Co$ structural material were predicted using different models. The nuclear level densities were calculated using different choices of available level density models in ALICE/ASH code. Finally, the newly calculated cross sections for the investigated nuclear reactions are compared with the experimental values and TENDL data based on TALYS nuclear code.