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1.
Inorg Chem ; 60(17): 12934-12940, 2021 Sep 06.
Article in English | MEDLINE | ID: mdl-34369748

ABSTRACT

Recently, the experimental discovery of high-Tc superconductivity in compressed hydrides H3S and LaH10 at megabar pressures has triggered searches for various superconducting superhydrides. It was experimentally observed that thorium superhydrides, ThH10 and ThH9, are stabilized at much lower pressures than LaH10. Based on first-principles density functional theory calculations, we reveal that the isolated Th frameworks of ThH10 and ThH9 have relatively more excess electrons in interstitial regions than the La framework of LaH10. Such interstitial excess electrons easily participate in the formation of the anionic H cage surrounding the metal atom. The resulting Coulomb attraction between cationic Th atoms and anionic H cages is estimated to be stronger than the corresponding one of LaH10, thereby giving rise to larger chemical precompressions in ThH10 and ThH9. Such a formation mechanism of H clathrates can also be applied to other superhydrides such as CeH9, PrH9, and NdH9. Our findings demonstrate that interstitial excess electrons in the isolated metal frameworks of high-pressure superhydrides play an important role in generating the chemical precompression of H clathrates.

2.
Sci Rep ; 10(1): 16878, 2020 Oct 09.
Article in English | MEDLINE | ID: mdl-33037271

ABSTRACT

The rare-earth metal hydrides with clathrate structures have been highly attractive because of their promising high-[Formula: see text] superconductivity at high pressure. Recently, cerium hydride [Formula: see text] composed of Ce-encapsulated clathrate H cages was synthesized at much lower pressures of 80-100 GPa, compared to other experimentally synthesized rare-earth hydrides such as [Formula: see text] and [Formula: see text]. Based on density-functional theory calculations, we find that the Ce 5p semicore and 4f/5d valence states strongly hybridize with the H 1s state, while a transfer of electrons occurs from Ce to H atoms. Further, we reveal that the delocalized nature of Ce 4f electrons plays an important role in the chemical precompression of clathrate H cages. Our findings not only suggest that the bonding nature between the Ce atoms and H cages is characterized as a mixture of ionic and covalent, but also have important implications for understanding the origin of enhanced chemical precompression that results in the lower pressures required for the synthesis of [Formula: see text].

3.
Article in English | MEDLINE | ID: mdl-32599887

ABSTRACT

We analyzed participants' feelings and arousal before, during, and after exercise as per whether they receive aromatherapy. Twenty university students who regularly took part in health exercises were selected through purposive sampling. Changes in feelings were measured through a 2D circumplex model and an in-depth interview. The effects on exercisers who received aromatherapy were more positive than for those who did not receive any treatment. Specifically, it induced positive feelings during exercise, reduced fatigue during exercise, and improved participants' feelings during the recovery period. Aroma has a key influence on exercisers' feelings, and it can positively influence exercise satisfaction and persistence.


Subject(s)
Aromatherapy , Emotions , Exercise , Affect , Fatigue , Humans
4.
J Korean Med Sci ; 32(1): 4-12, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27914125

ABSTRACT

A usual source of care (USC) in primary care improves health care quality and can result in improved health. However, current research about the type of USC (place only vs. physician with a place) is insufficient as an evidence to support the value of primary care. We analyzed data from the 2012 Korea Health Panel survey of adults aged 18 years or older (n = 11,873) who reported whether having a USC or not to compare the effects by type of USC on medical care use and out-of-pocket costs. Descriptive analysis showed significant differences in the distributions of sociodemographic and health status factors except frequency of outpatient visit by type of USC. Adjusted odds ratios (ORs) of having a physician with a place compared to not having a USC were 4.05 for age 65 ≥ years (vs. < 35 years), 1.33 for females (vs. males), 0.63 for the fifth (highest) quintile (vs. the first) of household income, 1.62 for medical aid (vs. employee) health insurance, and 4.46 for having a chronic disease (vs. not). For those having a physician with a place (vs. only a place) as a USC, adjusted ORs of hospital admission and emergency room (ER) visit were 0.77 and 0.71 with out-of-pocket costs not significantly high. Those having a physician with a place (vs. only a place) as a USC included more patients with chronic diseases, but they had fewer hospital admissions and ER visits. When designing a plan for health care reform in Korea, promoting having a physician rather than a place as a USC would be a better policy.


Subject(s)
Health Expenditures , Health Services Accessibility/economics , Physicians/economics , Adolescent , Adult , Age Factors , Aged , Emergency Medical Services , Female , Health Status , Humans , Insurance, Health , Linear Models , Male , Middle Aged , Odds Ratio , Primary Health Care , Republic of Korea , Sex Factors , Socioeconomic Factors
5.
Percept Mot Skills ; 123(1): 324-40, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27450864

ABSTRACT

The social cognitive theory model of physical activity is useful in understanding and promoting exercise. Self-regulation, as an element of the social cognitive theory model, is key to success in regular exercise participation. Existing research suggests that intrinsic motivation and positive emotion are associated with exercise participation and adherence. This study examined the relationships between self-regulation and exercise participation and adherence intention in university students when these two variables were controlled. Participants included 418 students enrolled in universities in Seoul (244 men, M age = 23.5 year, SD = 0.8; 174 women, M age = 22.8 year, SD = 1.0). The measures included the Self-Control Scale, exercise participation level, the Korea Exercise Adherence Intention Scale, the Korean Sport Participation Motivation scale, and the Korean Positive and Negative Affect Scale. Results showed that self-regulation ability was significantly associated with exercise participation level and adherence intention, when intrinsic motivation and positive emotion were controlled.


Subject(s)
Exercise/psychology , Intention , Self-Control/psychology , Students/psychology , Adult , Female , Humans , Male , Republic of Korea , Universities , Young Adult
6.
Psychol Rep ; 119(1): 39-54, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27381414

ABSTRACT

The study examined whether self-compassion mediates the relationship between social support and subjective well-being, as perceived by athletes. It also investigated the structural relationships between these variables. Participants were 333 athletes attending high school or university. Structural equation analysis showed that self-compassion partially mediated the relationship between social support and subjective well-being. To test the stability of the model, a multiple group analysis was performed according to sex of participant and school level, and this demonstrated that the model had similar fit to the data regardless of group. The confirmation that self-compassion plays an intermediary role in the relationship between social support and subjective well-being demonstrates that self-compassionate attitudes can be fostered by social support, and that, in turn, has a positive effect on an individual's subjective well-being.


Subject(s)
Athletes/psychology , Empathy , Personal Satisfaction , Self Concept , Social Support , Students/psychology , Adolescent , Adult , Female , Humans , Male , Republic of Korea , Young Adult
7.
Percept Mot Skills ; 120(1): 288-303, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25621525

ABSTRACT

This study examined whether parental attachment mediates the relationship between parental social support and self-esteem in Korean middle and high school athletes. 591 sports athletes attending middle and high schools that specialize in sport volunteered. Parental social support and parental attachment had a significant positive effect on self-esteem; parental attachment had a greater effect on self-esteem. In the structural relationship, direct effects of parental social support on self-esteem were weak, but indirect effects through parental attachment were strong. Therefore, parental attachment complementally mediated the relationship between parental social support and self-esteem. Metric invariance was supported for groups categorized by sex, region, and school level, confirming that the model could be applied to various groups.


Subject(s)
Athletes/psychology , Object Attachment , Parent-Child Relations/ethnology , Self Concept , Social Support , Students/psychology , Adolescent , Child , Female , Humans , Male , Republic of Korea/ethnology
8.
Ann Plast Surg ; 73(1): 77-80, 2014 Jul.
Article in English | MEDLINE | ID: mdl-23511740

ABSTRACT

BACKGROUNDS: The aims of the present study were to determine the exact level of separation of the upper lateral cartilage from the septal cartilage, and to classify the patterns of connection between the upper lateral cartilage and the lower lateral cartilage. METHODS: We dissected and photographed 60 sides of noses; 18 specimens were sectioned and stained with Masson's trichrome. RESULTS: The mean length of the connection between the upper lateral cartilage and septal cartilage was 16.1 mm. The mean level for separation of the upper lateral cartilage was 7.5 mm from the nasal bone. The pattern of connection between the upper lateral cartilage and lower lateral cartilage could be classified into five types: disconnection, end-to-end, overlap, scroll, and reverse scroll. CONCLUSIONS: The results of the present study will be helpful for surgical procedures such as nasal hump reduction and nasal cartilage work and also provide information for the anthropometric study of the nose.


Subject(s)
Asian People , Nasal Cartilages/anatomy & histology , Rhinoplasty , Aged , Aged, 80 and over , Anthropometry/methods , Female , Humans , Male , Middle Aged , Republic of Korea
9.
J Craniofac Surg ; 24(3): 1007-10, 2013 May.
Article in English | MEDLINE | ID: mdl-23714934

ABSTRACT

It is well known that facial beauty is dictated by facial type, and harmony between the eyes, nose, and mouth. Furthermore, facial impression is judged according to the overall facial contour and the relationship between the facial structures. The aims of the present study were to determine the optimal criteria for the assessment of gathering or separation of the facial structures and to define standardized ratios for centralization or decentralization of the facial structures.Four different lengths were measured, and 2 indexes were calculated from standardized photographs of 551 volunteers. Centralization and decentralization were assessed using the width index (interpupillary distance / facial width) and height index (eyes-mouth distance / facial height). The mean ranges of the width index and height index were 42.0 to 45.0 and 36.0 to 39.0, respectively. The width index did not differ with sex, but males had more decentralized faces, and females had more centralized faces, vertically. The incidence rate of decentralized faces among the men was 30.3%, and that of centralized faces among the women was 25.2%.The mean ranges in width and height indexes have been determined in a Korean population. Faces with width and height index scores under and over the median ranges are determined to be "centralized" and "decentralized," respectively.


Subject(s)
Asian People , Face/anatomy & histology , Adolescent , Adult , Beauty , Female , Humans , Male , Sex Factors , Young Adult
10.
Nat Prod Res ; 27(11): 1037-40, 2013.
Article in English | MEDLINE | ID: mdl-22607357

ABSTRACT

We isolated a sesquiterpene lactone from the methanol extract of the roots of Cosmos bipinnatus, namely, MDI (a mixture of dihydrocallitrisin and isohelenin). The anti-inflammatory activity of MDI was evaluated using lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. MDI significantly inhibited the expression of inducible nitric oxide synthase and cyclooxygenase-2. Consistent with these results, the production of NO and prostaglandin E2 (PGE2) was suggested to be suppressed by MDI in a concentration-dependent manner (IC50 value was 0.94 and 2.88 µg mL(-1) for NO and PGE2, respectively). In addition, MDI significantly inhibited the expressions of pro-inflammatory cytokines such as IL-1ß, IL-6, IFN-γ and TNF-α. Furthermore, MDI attenuated DNA-binding activity of NF-κB by inhibiting the phosphorylation of IκB. These results indicate that MDI isolated from the roots of C. bipinnatus shows anti-inflammatory activity in LPS-stimulated murine macrophages by modulating the NF-κB pathway.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Asteraceae/chemistry , Lipopolysaccharides/pharmacology , Plant Roots/chemistry , Animals , Cell Line , Mice
11.
Psychiatry Investig ; 8(2): 161-8, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21852994

ABSTRACT

OBJECTIVE: To analyze both differentially expressed genes and the Bcl-xL protein expression after acute and chronic treatment with fluoxetine in rat C6 glioma cells. METHODS: C6 glioma cells were cultured for 24 h or 72 h after treatment with 10 µM fluoxetine, and gene expression patterns were observed using microarray and qRT-PCR. Then, cells were cultured for 6 h, 24 h, 72 h or 96 h after treatment with 10 µM fluoxetine, and the expression of Bcl-xL protein was measured using western blot. RESULTS: As determined by microarray, treatment with fluoxetine for 24 h up-regulated 33 genes (including Bcl-xL and NCAM140) and down-regulated 7 genes (including cyclin G-associated kinase). Treatment with fluoxetine for 72 h up-regulated 53 genes (including Gsα and Bcl-xL) and down-regulated 77 genes (including Gαi2 and annexin V). Based on the qRT-PCR results, there was an increase in Gsα mRNA and a decrease in Gαi2 mRNA at 72 h in fluoxetine-treated cells as compared to control, a result that was consistent with microarray. We also observed an increase in Bcl-xL mRNA (both at 24 h and at 72 h) in fluoxetine-treated cells as compared to control, demonstrating a tendency to increase gradually. Bcl-xL protein expression increased as the duration of fluoxetine treatment increased. CONCLUSION: These results suggest that chronic treatment with fluoxetine not only initiates the cAMP pathway through inducing Gsα expression but also induces Bcl-xL expression, thus inhibiting apoptosis.

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