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This study investigated the causes of microstructural changes and the resultant electrical properties according to the sintering temperature of 0.96(K0.46−xNa0.54−x)Nb0.95Sb0.05O3-0.04Bi0.5(Na0.82K0.18)0.5ZrO3 lead-free ceramics by analyzing the correlation between vacancy concentrations and 2D nucleation. When sintered for 4 h, no grain growth occurred for the x = 0.000 composition over a wide temperature range, demonstrating that the existence of initial vacancies is essential for grain growth. As x increased, that is, as the vacancy concentration increased, the critical driving force (ΔGC) for 2D nucleation decreased, and abnormal grain growth was promoted. The number and size of these abnormal grains increased as the sintering temperature increased, but at sintering temperatures above 1100 °C, they decreased again owing to a large drop in ΔGC. The x = 0.005 specimen sintered at 1085 °C exhibited excellent piezoelectric properties of d33 = 498 pC/N and kp = 0.45 due to the large number of large abnormal grains with an 83% tetragonal phase fraction. The x = 0.000 specimen sintered at 1130 °C with suppressed grain growth exhibited good energy storage properties because of its very high relative density and small grain size of 300 to 400 nm. [ABSTRACT FROM AUTHOR]

This study investigated the perception bias on affective emoticons in individuals with emotion dysregulation and a maladaptive regulation strategy. A total of 289 students from the university completed 1) the Cognitive Emotional Regulation Questionnaire, including both adaptive and maladaptive cognitive emotional strategies, 2) the Difficulties in Emotion Regulation Scale, 3) an emoticon rating in terms of perception intensity, based on 6 basic emotions. Twenty-six emoticons from KakaoTalk, a popular messenger application in South Korea, were used after arousal whereupon valence ratings were obtained. The results revealed that individuals with emotion dysregulation significantly displayed stronger perception to ambiguous affect emoticons in anger and fear emotions, as compared to the control. These findings suggest that individuals with emotion dysregulation may be more influenced by negative affect stimuli which then leads to daily negative affect bias. [ABSTRACT FROM AUTHOR]

We investigated the differences in the emotional experiences of people who smoke and have damaged interoceptive awareness. Interoception is the sensation of the physiological condition of the body, and it has 2 biases: neglect and amplification of bodily feedback. We recruited 72 participants and divided them into 4 groups according to smoking status and interoceptive bias based on their scores on the Multidimensional Assessment of Interoceptive Awareness. All groups assessed their physiological and subjective arousal before and after watching video clips (positive–low arousal, positive–high arousal, negative–low arousal, negative–high arousal, neutral). The results indicated that people with amplification (vs. neglect) bias who smoked showed stronger subjective arousal to neutral stimuli. In contrast, people with amplification (vs. neglect) bias who did not smoke showed stronger subjective arousal to positive stimuli. These findings suggest that people who smoke and have an amplification bias could be more likely to misinterpret neutral emotional stimuli, leading to an increased craving for smoking. [ABSTRACT FROM AUTHOR]

Invasion and metastasis are among the main causes of death in patients with malignant tumors. Fisetin (3,3′,4′,7-tetrahydroxyflavone), a natural flavonoid found in the smoke tree (Cotinus coggygria), is known to have antimetastatic effects on prostate and lung cancers; however, the effect of fisetin on breast cancer metastasis is unknown. The aim of this study was to determine the anti-invasive activity of fisetin in human breast cancer cells. Matrix metalloproteinase (MMP)-9 is a major component facilitating the invasion of many cancer tumor cell types, and thus the inhibitory effect of fisetin on MMP-9 expression in 12- O -tetradecanoylphorbol-13-acetate (TPA)-stimulated human breast cancer cells was investigated in this study. Fisetin significantly attenuated TPA-induced cell invasion in MCF-7 human breast cancer cells, and was found to inhibit the activation of the PKCα/ROS/ERK1/2 and p38 MAPK signaling pathways. This effect was furthermore associated with reduced NF-κB activation, suggesting that the anti-invasive effect of fisetin on MCF-7 cells may result from inhibited TPA activation of NF-κB and reduced TPA activation of PKCα/ROS/ERK1/2 and p38 MAPK signals, ultimately leading to the downregulation of MMP-9 expression. Our findings indicate the role of fisetin in MCF-7 cell invasion, and clarify the underlying molecular mechanisms of this role, suggesting fisetin as a potential chemopreventive agent for breast cancer metastasis. [ABSTRACT FROM AUTHOR]

The high-performance bio-based elastomer, poly (1, 4-cyclohexanedimethanol succinate- co -citrate) (PCSC), was successfully synthesized through the combination of melt polymerization and hot pressing. Owing to the structural characteristics of citric acid (CA), an effective process of thermal- and pressure-integrated crosslinking was possible, revealing CA to be a progressive tetra-functional monomer. In the composition of PCSC, there can be four types of ester bonds amongst monomers, of which CA was used in three. Specifically, the stepwise hot-pressing method allowed β-carboxylic acid and hydroxyl group of CA to remain within the synthesized elastomer to enhance its crosslinking density via esterification. As a result, the synthesized PCSC possessed a wide range of mechanical properties along with good thermal resistance. The resulting characteristics were demonstrated by fourier-transform infrared spectroscopy (FT-IR), two-dimensional correlation spectroscopy (2D-COS), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile and swelling tests. PCSC is a sustainable and versatile material that can be utilized in the field of engineering. [ABSTRACT FROM AUTHOR]

Portulaca oleracea L. is a traditional oriental medicine known for its pharmacological effects. The present study aimed to investigate the immunostimulatory effects of PPCE on cyclophosphamide-stimulated rat model and in isolated spleen cells. The result showed that PPCE exerted an immunostimulatory effect in vivo and in vitro. Specifically, PPCE significantly enhanced splenocyte proliferation and upregulated inflammatory cytokines (IL-2, IL-12, TNF-α, and IFN-γ) and NK cell activity in vitro. The immunostimulatory effect was further investigated through various immunological assays. Oral administration of PPCE increased the swimming time and number of immune cells in rats. Histological analysis revealed that PPCE administration exerted splenic recovery. Thus, P. oleracea L. based complex extracts may be used as an immunostimulatory agent in medicine or functional foods. [ABSTRACT FROM AUTHOR]