• Medical Lasers
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• 제9권2호
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• pp.142-149
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• 2020

Background and Objectives A picosecond-domain laser treatment using a microlens array (MLA) or a diffractive optical element elicits therapeutic micro-injury zones in the skin. This study examined the patterns of tissue reactions after delivering multiple pulses of 1,064-nm, MLA-type, picosecond neodymium:yttrium-aluminum-garnet laser treatment. Materials and Methods Multiple pulses of picosecond laser treatment were delivered to ex vivo human or brown micropig skin and analyzed histopathologically. A high-speed cinematographic study was performed to visualize the multiple pulses of picosecond laser energy-induced skin reactions in in vivo human skin. Results In the ex vivo human skin, a picosecond laser treatment at a fluence of 0.3 J/cm² over 100 non-stacking passes generated multiple lesions of thermally-initiated laser-induced optical breakdown (TI-LIOB) in the epidermis and dermis. In the ex vivo micropig skin, stacking pulses of 20, 40, 60, 80, and 100 at a fluence of 0.3 J/cm² generated distinct round to oval zones of tissue coagulation in the mid to lower dermis. High-speed cinematography captured various patterns of twinkling, micro-spot reactions on the skin surface over 100 stacked pulses of a picosecond laser treatment. Conclusion Multiple pulses of 1,064-nm, MLA-type, picosecond laser treatment elicit marked TI-LIOB reactions in the epidermis and areas of round to oval thermal coagulation in the mid to deep dermis.

• Korean Chemical Engineering Research
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• 제52권6호
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• pp.713-719
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• 2014

4성분계 다중반응이 반응증류 탑 내에서 발생할 때 증류거동의 변화를 시각화 방법을 통해 분석하였다. 시각화 방법이란 단순 증류의 물질수지에 각 반응에 의한 벡터를 추가하고 이를 공간상에 표현하는 것으로 각 단에서 혼합물의 조성 변화 및 반응의 진척도를 직관적으로 알 수 있다. 또한 이를 통해 주어진 운전조건에서 필요한 총 단수 및 최적반응 단의 위치를 결정할 수 있다. 본 연구에서는 에틸렌글리콜(Ethylene glycol) 생산공정을 시각화 방법을 통해 분석하였다. 제안된 시각화 방법을 사용하여 복잡한 실험이나 공정모사 없이 4성분계 다중반응증류 공정에 대한 타당성 평가 및 분석이 가능하다.

• 한국보육지원학회지
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• 제13권3호
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• pp.83-102
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• 2017

Objective: This study investigates the main effects and interaction effects of mother's reactions to young children's negative emotions on the children's problem behaviors. Methods: A total of 346 mothers with toddlers completed questionnaires, the data were analyzed using Pearson's correlation coefficient and multiple regression. Results: First, mothers' supportive response to young children's negative emotions, including expressive encouragement, emotion-focused reactions, and problem-focused reactions, showed negative relations with the children's internal and external problem behaviors. Mothers' unsupportive response to children's negative emotions, including distress reactions, minimization reactions, and punitive reactions, showed positive relations with the children's internal and external problem behaviors. Second, an interactive effect was observed. For external problem behavior, mothers' lower distress reactions accompanied by higher emotion-focused reactions, lower punitive reactions accompanied by higher emotion-focused reactions, lower distress reactions accompanied by higher problem-focused reactions, and lower punitive reactions accompanied by higher problem-focused reactions all decreased children′s problem behavior. However, for internal problem behavior, only mothers' lower distress reactions accompanied by higher emotion-focused reaction decreased children′s problem behavior. Conclusion/Implication: The main interaction effect on mothers' reaction to young children's negative emotional expression shows that preventive intervention is needed to address problem behavior.

• Bulletin of the Korean Chemical Society
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• 제26권12호
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• pp.1953-1961
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• 2005

We have performed high-level quantum mechanical calculation for multiple proton transfer in HOCl + HCl and $H_2O$ + $ClONO_2$ on water clusters, which can be used as a model of the reactions on ice surface in stratospheric clouds. Multiple proton transfer on ice surface plays crucial role in these reactions. The structures of the clusters with 0-3 water molecules and the transition state structures for the multiple proton transfer have been calculated. The energies and barrier heights of the proton transfer were calculated at various levels of theory including multi-coefficient correlated quantum mechanical methods (MCCM) that have recently been developed. The transition state structures and the predicted reaction mechanism depend very much on the level of theory. In particular, the HF level can not correctly predict the TS structure and barrier heights, so the electron correlation should be considered appropriately.

• 대한방사선기술학회지:방사선기술과학
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• 제44권1호
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• pp.47-52
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• 2021

The incidence of adverse reactions to iodide contrast media was found to have increased owing to their increased use in computed tomography, but the exact reasons were unknown. Based on reported iodide contrast media adverse reactions data, it is recommended to the components of iodide contrast media before use to minimize adverse reactions. It was found that the use of iopromide and iomeprol in iodide contrast media resulted in a higher incidences of death and threat of life resulting from adverse reactions than other ingredients. Patients who are administered iodide contrast media containing iopromide and iomeprol during the computed tomography test should be carefully examined by the relevant medical professional, as the significance of gender and age varies from component to component. As multiple iodide contrast agents are available, the use of an appropriate iodide contrast media will reduce the incidence of iodide contrast media adverse reactions.

• Bulletin of the Korean Chemical Society
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• 제27권4호
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• pp.463-472
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• 2006

The preparation of enatiomerically enriched homoallylic alcohols through asymmetric addition of chiral allylic transfer reagents and allylating reagents with chiral catalysts to the carbonyl functionalities represents an important chemical transformation. Excellent progress has been made over past decade in the development and application of catalytic asymmetric allylic transfer reactions. In this account, our efforts for the various intermolecular allylic transfer reactions such as allylation, propargylation, allenylation, and dienylation utilizing accelerating strategy and sequential allylic transfer reactions to achieve multiple stereoselection mainly using transition metal catalysts are described.

• 인간식물환경학회지
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• 제24권2호
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• pp.209-218
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• 2021

Background and objective: Instagram, an image-based social media, is being used as an important outlet for the communication and place marketing of public spaces. The purpose of this paper was to analyze how types of place-based content affect user reactions (Likes and Comments) on Instagram in order to provide basic data on the operation and utilization of social media by public places such as botanical gardens and arboretums. Methods: A total of 850 posts uploaded to the Instagram account of Kew Gardens from November 6, 2014 to July 3, 2020 were classified using 14 subject codes. Multiple regression analysis was performed to evaluate the user's reaction between the dependent variables ("Likes", "Comments") and the independent variables (14 subject codes). Results: The findings showed that user reactions appear to differ depending on the typology of the content, and "Likes" and "Comments" were presented in independent behavioral reactions. In particular, "close-ups of plants (botanic, macro)," "plant colony (botanic, wide)," "place-specific landscape (building, landscape)," "anniversary" and "information" showed positive impacts on both "Likes" and "Comments"which could lead to electronic word-of-mouth and content sharing. Conclusion: Based on these findings, it can be argued that the typology of a botanical garden's content can be used to determine factors that affect the immediate reactions and enhance engagement with users.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.310.1-310.1
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• 2013

We show the novel hot electron based-solar energy conversion using tandem structured Schottky diode with double Schottky barriers. In this report, we show the effect of the double Schottky barriers on solar cell performance by enhancing both of internal photoemission and band-to-band excitation. The tandem structured Au/Si diode capped with TiO2 layer as second semiconductor exhibited improved ability for light harvesting. The proposed mechanisms consist of multiple reflections of hot electrons and additional pathway of solar energy conversion due to presence of multiple interfaces between thin gold film and semiconductors. Short-circuit photocurrent measured on the tandem structured Au/Si diodes under illumination of AM1.5 increased by approximately 70% from 3.1% to 5.3% and overall incident photon to electron conversion efficiency (IPCE) was enhanced in visible light, revealing that the concept of the double Schottky barriers have significant potential as novel strategy for light harvesting.

• 대한의생명과학회지
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• 제12권1호
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• pp.35-42
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• 2006

Alloimmunization to red blood cell (RBC) antigens may cause a delayed hemolytic transfusion reactions (DHTR) and a delayed serologic transfusion reactions (DSTR). In the present study, the frequency of alloimmunization and its clinical significance were evaluated. Also, transfusions were correlated with antibody formation. Alloimmunization rate was 0.63%. Alloimmunization rate in multiple transfused patients was 24.5%. The most common clinically significant alloantibodies of alloimmunized patients were found to be Rh antibodies (52.6%). Nine patients out of 38 (23.7%) became undetectable after the first detection. To be positive at antibody screening test after RBC transfusion was mean transfused numbers: 3.7 units, mean transfused periods: 56 days, mean transfused frequencies: 1.7 times. The results from antibody specificity and RBC transfusions were comparatively analyzed and it shows that Rh system antibodies were longer than other antibodies (P<0.05). In case of disease group, malignant diseases was longer than other diseases (P<0.05). In order to prevent the formation of RBC alloimmunization, irregular antibody screening tests were performed at propriety intervals in multiple transfused patients.

• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1181-1185
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• 2006

By using two different computer simulation methods, of which one produces exact results while the other is based on the Wilemski-Fixman closure approximation, we evaluate the utility of closure approximation in calculating the rates of diffusion-controlled reactions involving a reactant with multiple reaction sites. We find that errors in the estimates of steady-state rate constants due to closure approximation are not so large. We thus propose an approximate analytic expression for the rate constant based on the closure approximation.