• Bulletin of the Korean Chemical Society
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• v.18 no.4
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• pp.390-394
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• 1997

Nucleophilic substitution reactions of 2-thiopheneethyl benzenesulfonates (2-TEB) and 3-thiopheneethyl benzenesulfonates (3-TEB) with anilines and N,N-dimethylanilines (DMA) are investigated in acetonitrile at 60.0 ℃. The cross-interaction constants ρxz determined for the reactions with anilines are large negative (- 0.50) which are comparable to those for the similar predominantly frontside-attack SN2 reactions of 1-phenylethyl (1-PEB), 2-phenylethyl (2-PEB) and cumyl benzenesulfonates. A large negative ρxz value (- 0.4∼- 0.8) is considered to provide a mechanistic criterion for the frontside-attack SN2 mechanism with a four-center transition state. In agreement with this proposal the kinetic isotope effects, kH/kD, involving deuterated aniline nucleophiles are all greater than one reflecting partial N-H(D) bond cleavage in the transition state. The MO theoretical reactant structures of 1-PEB, 2-PEB and 2-TEB based on the PM3 calculation show that the benzene ring blocks the backside nucleophile approach to the reaction center carbon (Cα) enforcing the frontside-attack SN2 mechanism.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.2
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• pp.161-168
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• 2015

Horizontally curved bridges are subjected to torsional loads by their vertical dead loads only as well as eccentric loads, which cause negative reactions at supports. In this paper, effects of bridge curvature on vertical reactions at supports are investigated for 48.8 m length simple span steel box girder bridges with elastomeric bearings by varying curvature angle from 0.49 to 1.35 rad. In order to expect magnitude and direction of reactions including possibility of negative reactions, reaction evaluation equations have been analytically developed by separating a superstructure of curved bridge into independent components. Concrete slabs and bottom flanges in steel box section are assumed geometrical annular sectors in area dimension, and top flanges and webs that have very narrow projected areas are assumed geometrical arcs in line dimension. Proposed equations have relatively simple forms and prediction values are on very good agreement with those from finite element analyses by difference of 1% order.

• Korean Journal of Animal Reproduction
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• v.22 no.1
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• pp.19-27
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• 1998

The present study was performed to investigate the patterns of a, pp.arance of lectin in uterus of fetuses of 90 and 120 days old and neonates of Korean native goat. The carbohydrate markers were used in histochemistry for the determination of the lectin by staining of avidin-biotin-per-oxidase complex(ABC), rincinus communis agglutinin(RCA-I), ulexeuropalus communis agglutinin(UEA) and wheat germ agglutinin(WGA). 1. The effects of this study were as follows; 1. The binding reactions for Con-A were weak on the mucosal epithelium of endometrium in 90 and 120 days old fetuses, and neonates and moderate at the free surface of mucosal epithelia. 2. The binding reactions for DBA was partially moderate on the mucosal epithelium of endometrium and partially strong at the free surface of mucosal epithelia in 120 days old fetuses. In neonates, the reactions were strong on the mucosal epithelium and gland primordium of endometrium, and the secretions at the free surface showed strong reactions for DBA. But, in 90 days old fetuses, the reaction was negative. 3. The binding reactions for RCA-I were moderate on the mucosal epithelium of endometrium and at the free surface of mucosal epithelia in 90 days old fetuses. In 120 days old fetuses, the reactions were weak on the mucosal epithelium of endometrium and moderate at the free surface of mucosal epithelia. In neonates, the reactions were moderate on the mucosal epithelium of endometrium and strong at the free surface of mucosal epithelia and also strong in the uterine gland. 4. The binding reactions for UEA were negative in 90 and 120 days old fetuses and neonates. 5. In 90 days old fetuses, the binding reactions for WGA were generally weak on the mucosal epithelium of endometrium, but several epithelial cells showed moderate reaction for WGA. In 120 days old fetuses and neonates, the reactions were moderate on the mucosal epithelium and blood vessels of endometrium and strong at the free surface of mucosal epithelia.

• Journal of the Korea Society of Computer and Information
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• v.16 no.5
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• pp.173-183
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• 2011

The purpose of this study is to suggest the policy implications through the analysis on the effects of social workers' negative reactions for client violence on burnout. Especially, This study is focused on identifying the moderating effects of demographic characteristics and institutional confrontations system. This study was carried out based on survey of social workers on social welfare facilities located in G metropolitan city and J province. The major findings can be summarized as follows. First, Social workers' negative reactions toward client violence affect on burnout significantly. Second, demographic characteristics and institutional confrontations system moderate the relationship between social workers' negative reactions toward client violence and their burnout. This study suggested some implications basing on the analytical results.

• ETRI Journal
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• v.46 no.2
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• pp.290-306
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• 2024

To treat the novel COronaVIrus Disease (COVID), comparatively fewer medicines have been approved. Due to the global pandemic status of COVID, several medicines are being developed to treat patients. The modern COVID medicines development process has various challenges, including predicting and detecting hazardous COVID medicine responses. Moreover, correctly predicting harmful COVID medicine reactions is essential for health safety. Significant developments in computational models in medicine development can make it possible to identify adverse COVID medicine reactions. Since the beginning of the COVID pandemic, there has been significant demand for developing COVID medicines. Therefore, this paper presents the transferlearning methodology and a multilabel convolutional neural network for COVID (MLCNN-COV) medicines development model to identify negative responses of COVID medicines. For analysis, a framework is proposed with five multilabel transfer-learning models, namely, MobileNetv2, ResNet50, VGG19, DenseNet201, and Inceptionv3, and an MLCNN-COV model is designed with an image augmentation (IA) technique and validated through experiments on the image of three-dimensional chemical conformer of 17 number of COVID medicines. The RGB color channel is utilized to represent the feature of the image, and image features are extracted by employing the Convolution2D and MaxPooling2D layer. The findings of the current MLCNN-COV are promising, and it can identify individual adverse reactions of medicines, with the accuracy ranging from 88.24% to 100%, which outperformed the transfer-learning model's performance. It shows that three-dimensional conformers adequately identify negative COVID medicine responses.

• Journal of the Korean Home Economics Association
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• v.44 no.1 s.215
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• pp.75-85
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• 2006

Emotional expressiveness is a pathway by which parents affect the emotional competence of their children. This study examined how the emotional expressiveness of parents is influenced by the emotional reactions of their children and demographic characteristics within a family context. Data for the present study were from 200 parents in 100 two-parent families who completed self-report questionnaires for emotional expressiveness, children's emotional reactions to stressful situations, and demographics. In preliminary analyses, mothers expressed emotions more frequently than fathers did, and mothers with high expressiveness of positive emotions were more educated and had higher family income. Although fathers' emotional expressiveness was closely related to mothers' expressiveness, none of the demographic factors were related to fathers' expressiveness. When all predictors were considered in hierarchical multiple regressions, family income was the significant predictor for mothers' positive expressiveness, whereas mothers' negative expressiveness were explained by children's emotional reactions, mother education, child sex, the number of siblings, fathers' education, and mothers' time spent with children. When controlled for mothers' expressiveness, fathers' time spent with children was the only significant predictor for fathers' negative expressiveness. The results of this study suggested that parents' emotional expressiveness varied with socioeconomic status. The discussion also examines the gender differences between mothers and fathers in emotional expressiveness, and their relations to children's sex.

• Journal of Family Relations
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• v.22 no.3
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• pp.29-46
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• 2017

Objectives: The purpose of this study was to investigate a role of self-compassion in conflict resolution strategies among dating couples. Further, we examined conflict resolution strategies as mechanisms to explain in the relationship between self-compassion and relationship satisfaction. Method: Two hundred forty two dating couples were recruited. Actor and Partner Independence Model(APIM) was used to examine actor and partner effects of self-compassion on relationship satisfaction as well as conflict resolution strategies. The total of 4 APIMs, two positive conflict resolution strategies(i.e., positive emotional reactions, active coping) and two negative conflict resolution strategies(i.e., negative emotional reactions and hostility, avoidance) were analyzed. Positive conflict resolution strategies had only actor effect in the link between self-compassion and relationship satisfaction. That is, self-compassionate men and women were more likely to use positive conflict resolution strategies and, in turn, led to their higher relationship satisfaction. Both actor and partner effects were found in the negative conflict resolution strategy models. In terms of actor effect self-compassionate men and women were less likely to use negative conflict resolution strategies and that, in turn, led to their higher relationship satisfaction. In terms of partner effects we found that women's negative emotional reactions and hostility mediated the link between women's self-compassion and their male partners' relationship satisfaction. Men's avoidance mediated the link between men's self-compassion and their female partners' relationship satisfaction.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1199-1203
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• 2010

Second-order rate constants ($k_N$) have been measured spectrophotometrically for Michael-type reactions of 1-(X-substituted phenyl)-2-propyn-1-ones (2a-f) with a series of alicyclic secondary amines in MeCN at $25.0{\pm}0.1^{\circ}C$. The $k_N$ value increases as the incoming amine becomes more basic and the substituent X changes form an electron-donating group (EDG) to an electron-withdrawing group (EWG). The Br${\o}$nsted-type plots are linear with ${\beta}_{nuc}$ = 0.48 - 0.51. The Hammett plots for the reactions of 2a-f exhibit poor correlations but the corresponding Yukawa-Tsuno plots result in much better linear correlations with ${\rho}$ = 1.57 and r = 0.46 for the reactions with piperidine while ${\rho}$ = 1.72 and r = 0.39 for those with morpholine. The amines employed in this study are less reactive in MeCN than in water for reactions with substrates possessing an EDG, although they are ca. 8 pKa units more basic in the aprotic solvent. This indicates that the transition state (TS) is significantly more destabilized than the ground state (GS) in the aprotic solvent. It has been concluded that the reactions proceed through a stepwise mechanism with a partially charged TS, since such TS would be destabilized in the aprotic solvent due to the electronic repulsion between the negative-dipole end of MeCN and the negative charge of the TS. The fact that primary deuterium kinetic effect is absent supports a stepwise mechanism in which proton transfer occurs after the rate-determining step.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.2955-2959
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• 2011

Second-order rate constants for nucleophilic substitution reactions of 2,4-dinitrophenyl benzenesulfonate 1a with a series of alicyclic secondary amines in MeCN have been measured spectrophotometrically and compared with those reported previously for the corresponding reactions performed in aqueous medium to investigate the effect of medium on reactivity and reaction mechanism. The amines employed in this study are found to be more reactive in the aprotic solvent than in $H_2O$. The reactions of 1a in MeCN result in a linear Br${\o}$nsted-type plot with ${\beta}_{nuc}$ = 0.58, which contrasts to the curved Br${\o}$nsted-type plot reported previously for the corresponding reactions performed in the aqueous medium (i.e., ${\beta}_2$ = 0.86 and ${\beta}_1$ = 0.38). Accordingly, it has been concluded that the reaction mechanism changes from a stepwise mechanism to a concerted pathway upon changing the medium from $H_2O$ to MeCN. Reactions of Y-substituted phenyl benzenesulfonates 1a-c with piperidine in MeCN result in a linear Br${\o}$nsted-type plot with ${\beta}_{lg}$ = -1.31, indicating that expulsion of the leaving group is significantly more advanced than bond formation in the transition state. The trigonal bipyramidal intermediate ($TBPy^{\pm}$) proposed previously for the reactions in $H_2O$ would be highly unstable in MeCN due to strong repulsion between the negative charge in $TBPy^{\pm}$ and the negative dipole end of MeCN. Thus, destabilization of $TBPy^{\pm}$ in MeCN has been concluded to change the reaction mechanism from a stepwise mechanism to a concerted pathway.

• Child Studies in Asia-Pacific Contexts
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• v.6 no.2
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• pp.47-57
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• 2016

This study investigated whether Korean mothers' emotion socialization beliefs are related to emotional functioning in children differing across gender. We interviewed Korean mothers (N = 100) of first graders (55 boys; 45 girls) about their sensitivity, their reactions to children's distress, and children's emotion regulation. Two components of emotion regulation were distinguished: regulation and negativity. Results revealed that mothers' proactive sensitivity and their supportive reactions were related to their children's regulation, whereas unsupportive reactions were related to children's negativity. Child gender moderated the associations between mothers' socialization beliefs and children's emotion regulation: mothers' proactive sensitivity was more strongly associated with competent regulation in girls than in boys. Mothers' unsupportive reactions were related to increased negativity only in girls. Results are discussed from a cultural perspective, focusing on gender differences in the links between maternal socialization and children's emotional outcomes in Korea.