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1.
Analyst ; 146(7): 2374-2382, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33646207

RESUMO

It has been reported that the scattering cross-sections of resonance Raman spectra strongly depend on the resonance between the laser's excitation energy and the electronic absorption band of pigments in solution. However, the actual collection of scattered photons is affected by diffuse scattering and self-absorption when studying painted colorants in artworks. Quantitative spectroscopic measurements are required to elucidate the apparent resonance Raman cross-sections in both solution and solid. In this study, we explored the excitation-dependent Raman scattering of natural and artificial Korean pigments painted on a wood block with six visible wavelengths. Our study shows that the Raman intensity profile agrees with the emission profile rather than with the absorption. We also assessed the validity of self-absorption and the outgoing resonance mechanism in the solid state for the results.

2.
Psychol Trauma ; 13(5): 565-574, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32969704

RESUMO

OBJECTIVE: Embitterment encapsulates reactive emotions such as worthlessness or helplessness after negative life events that contravene one's basic beliefs. However, no psychological model of the development of persistent embitterment has yet been investigated. We examined mediating factors for reactive embitterment, focusing on cognitive processes, including coping and rumination, among young South Korean adults. METHOD: A total of 1,000 young adults aged 18-35 answered an online survey questionnaire measuring distress caused by negative life events, coping strategies, rumination, and embitterment. To examine the mediating associations of coping and rumination with embitterment, we tested path analysis models separately. RESULTS: Distress was both directly and indirectly related to embitterment (mediated by maladaptive strategies of dysfunctional coping and intrusive rumination; total association ß = .54, p < .001). The estimated indirect association of distress via maladaptive strategy with embitterment was 0.45, accounting for 82.4% of the total association of distress on embitterment. The ratio of indirect association via maladaptive strategy to direct association was 4.64. The results of this study have implications for better clinical understanding and treatment of embitterment. CONCLUSIONS: The association between dysfunctional strategies and embitterment severity suggests that clinicians should attenuate potential aggravating factors, including dysfunctional coping and intrusive rumination. Given that a combination of dysfunctional coping approaches increased the risk of reactive embitterment fourfold, these variables can be regarded as important for the development of preventive service programs for people at risk of embitterment. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Adaptação Psicológica , Emoções , Humanos , Inquéritos e Questionários , Adulto Jovem
3.
ACS Appl Mater Interfaces ; 12(2): 2370-2379, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31845795

RESUMO

While several proton-conducting anode materials have shown excellent tolerance to sulfur poisoning, the mechanism is still unclear due largely to the inability to probe miniscule amounts of sulfur-containing species using conventional surface characterization techniques. Here we present our findings in unraveling the mechanism of water-mediated sulfur tolerance of a proton conductor under operating conditions empowered by surface-sensitive, operando surface-enhanced Raman spectroscopy (SERS) coupled with impedance spectroscopy. Contrary to the conventional view that surface-adsorbed sulfur is removed mainly by oxygen anions, it is found that -SO4 groups on the surface of the proton conductor are converted to SO2 by a water-mediated process, as confirmed by operando SERS analysis and density functional theory (DFT)-based calculations. The combination of operando SERS performed on a model electrode and theoretical computation offers an effective approach to investigate into complex mechanisms of electrode processes in various electrochemical systems, providing information vital to achieve the rational design of better electrode materials.

4.
J Korean Med Sci ; 34(4): e29, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30686951

RESUMO

To substantiate psychological symptoms following humidifier disinfectant (HD) disasters, counseling records of 26 victims and 92 family members of victims (45 were bereaved) were analyzed retrospectively. Among the victims, 34.6% had Clinical Global Impression-Severity scores of over 4, which meant they were moderately ill. While anxiety/fear and depression with respiratory symptoms were frequently observed in victims and family members, chronic psychological distress such as alcohol/smoking abuse and insomnia was relatively high in bereaved family members. In conclusion, it is important to provide mental health support for victims and their families, focusing on the characteristic symptoms of each group as well as monetary compensation.


Assuntos
Vítimas de Desastres/psicologia , Desinfetantes/efeitos adversos , Família/psicologia , Lesão Pulmonar/etiologia , Estresse Psicológico , Adulto , Feminino , Humanos , Umidificadores , Lesão Pulmonar/psicologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Nat Commun ; 8: 14586, 2017 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-28240282

RESUMO

Rechargeable metal-air batteries and water splitting are highly competitive options for a sustainable energy future, but their commercialization is hindered by the absence of cost-effective, highly efficient and stable catalysts for the oxygen evolution reaction. Here we report the rational design and synthesis of a double perovskite PrBa0.5Sr0.5Co1.5Fe0.5O5+δ nanofiber as a highly efficient and robust catalyst for the oxygen evolution reaction. Co-doping of strontium and iron into PrBaCo2O5+δ is found to be very effective in enhancing intrinsic activity (normalized by the geometrical surface area, ∼4.7 times), as validated by electrochemical measurements and first-principles calculations. Further, the nanofiber morphology enhances its mass activity remarkably (by ∼20 times) as the diameter is reduced to ∼20 nm, attributed to the increased surface area and an unexpected intrinsic activity enhancement due possibly to a favourable eg electron filling associated with partial surface reduction, as unravelled from chemical titration and electron energy-loss spectroscopy.

6.
Shinrigaku Kenkyu ; 87(6): 644-50, 2017 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-29630302

RESUMO

This study investigated posttraumatic stress symptoms and posttraumatic growth among 534 fire fighters who were dispatched to the disaster area following the Great East Japan Earthquake. Specifically, we investigated the effect of acute stress symptoms and social support from peers and family on posttraumatic stress symptoms, depression, and posttraumatic growth one year after being dispatched. We found that dispatched fire fighters experienced posttraumatic growth as well as posttraumatic stress symptoms following disaster work. Moreover, social support from peers was positively associated with professional growth as a disaster worker, whereas social support from family positively associated with gratitude. These results imply that it is useful to take into consideration supporting the posttraumatic growth of fire fighters as an opportunity for professional growth with respect to stress management programs as well as relieving posttraumatic symptoms with early intervention.


Assuntos
Bombeiros , Transtornos de Estresse Pós-Traumáticos , Adulto , Terremotos , Humanos , Japão , Pessoa de Meia-Idade , Estresse Psicológico , Inquéritos e Questionários
7.
Adv Sci (Weinh) ; 3(1): 1500205, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-27722079

RESUMO

An activated carbon nanofiber (CNF) is prepared with incorporated Fe-N-doped graphene nanoplatelets (Fe@NGnPs), via a novel and simple synthesis approach. The activated CNF-Fe@NGnP catalysts exhibit substantially improved activity for the oxygen reduction reaction compared to those of commercial carbon blacks and Pt/carbon catalysts.

8.
ChemSusChem ; 8(18): 3153-8, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26227300

RESUMO

This study focuses on reducing the cathode polarization resistance through the use of mixed ionic electronic conductors and the optimization of cathode microstructure to increase the number of electrochemically active sites. Among the available mixed ionic electronic conductors (MIECs), the layered perovskite GdBa0.5 Sr0.5 CoFeO5+δ (GBSCF) was chosen as a cathode material for intermediate temperature solid oxide fuel cells owing to its excellent electrochemical performance and structural stability. The optimized microstructure of a GBSCF-yttria-stabilized zirconia (YSZ) composite cathode was prepared through an infiltration method with careful control of the sintering temperature to achieve high surface area, adequate porosity, and well-organized connection between nanosized particles to transfer electrons. A symmetric cell shows outstanding results, with the cathode exhibiting an area-specific resistance of 0.006â€…Ω cm(2) at 700 °C. The maximum power density of a single cell using Ce-Pd anode with a thickness of ∼80 µm electrolyte was ∼0.6 W cm(-2) at 700 °C.

9.
Nat Commun ; 6: 7123, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-25997811

RESUMO

Heteroatom doping into the graphitic frameworks have been intensively studied for the development of metal-free electrocatalysts. However, the choice of heteroatoms is limited to non-metallic elements and heteroatom-doped graphitic materials do not satisfy commercial demands in terms of cost and stability. Here we realize doping semimetal antimony (Sb) at the edges of graphene nanoplatelets (GnPs) via a simple mechanochemical reaction between pristine graphite and solid Sb. The covalent bonding of the metalloid Sb with the graphitic carbon is visualized using atomic-resolution transmission electron microscopy. The Sb-doped GnPs display zero loss of electrocatalytic activity for oxygen reduction reaction even after 100,000 cycles. Density functional theory calculations indicate that the multiple oxidation states (Sb(3+) and Sb(5+)) of Sb are responsible for the unusual electrochemical stability. Sb-doped GnPs may provide new insights and practical methods for designing stable carbon-based electrocatalysts.

10.
Shinrigaku Kenkyu ; 85(6): 590-5, 2015 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-25799871

RESUMO

Fund-raising activities on behalf of victims of the 2011 Great East Japan Earthquake during the year after the earthquake were investigated in residents of the South Kanto area (N = 749), which is adjacent to the disaster area. The percentage of people that raised funds was 67.4%. We investigated the effects of the following on fundraising activities: demographic variables (sex, age, and educational background), trait empathy (empathic concern, perspective taking, and personal distress), former experience with fund-raising activities, effects of similarity to victims (e.g., experienced inconveniences because of the disaster, or had problems returning home), and psychological closeness to victims (e.g, have family members or acquaintances that suffered from the disaster, or that once lived in the disaster area). The results indicated that fund-raising activities were affected by former experience with fund-raising, similarity to victims, psychological closeness to victims, empathic concern, and being female. The relationship between fund-raising activities for victims and empathy are discussed.


Assuntos
Terremotos , Empatia , Obtenção de Fundos , Adulto , Escolaridade , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade
11.
Angew Chem Int Ed Engl ; 53(48): 13064-7, 2014 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-25200006

RESUMO

A class of double-perovskite compounds display fast oxygen ion diffusion and high catalytic activity toward oxygen reduction while maintaining excellent compatibility with the electrolyte. The astoundingly extended stability of NdBa(1-x)Ca(x)Co2O(5+δ) (NBCaCO) under both air and CO2-containing atmosphere is reported along with excellent electrochemical performance by only Ca doping into the A site of NdBaCo2O(5+δ) (NBCO). The enhanced stability can be ascribed to both the increased electron affinity of mobile oxygen species with Ca, determined through density functional theory calculations and the increased redox stability from the coulometric titration.

12.
Artigo em Inglês | MEDLINE | ID: mdl-24563730

RESUMO

BACKGROUND: The representation of low- and middle-income countries (LMIC) in traumatic stress research is important to establish a global evidence base, build research capacity, and reduce the burden of unmet mental health needs around the world. Reviews of the traumatic stress literature up to 2002 showed trends toward globalization although LMIC were only marginally represented compared to high-income countries (HIC). OBJECTIVE: To examine the global nature of current traumatic stress research. In particular, we were interested in the extent to which traumatic stress research is: (1) conducted in LMIC, (2) conducted by LMIC researchers, and (3) accessible to them. METHOD: Using the databases PubMed, PsychInfo, and PILOTS, we systematically searched for peer-reviewed articles on traumatic stress published in any language in the year 2012. Out of the 3,123 unique papers identified, we coded a random sample (N=1,000) for study, author, article, and journal characteristics. RESULTS: Although our sample involved research in 56 different countries, most papers (87%) involved research in HIC, with 51% of all papers describing studies in the United States. In 88% of the papers, the author team was affiliated with HIC only. Less than 5% of all author teams involved collaborations between HIC and LMIC researchers. Moreover, 45% of the articles on LMIC studies published by a HIC corresponding author did not involve any LMIC co-authors. LMIC researchers appeared to publish empirical studies in lower impact journals. Of the 1,000 articles in our sample, 32% were open access and 10% were made available via different means; over half of the papers were not accessible without subscription. CONCLUSIONS: Traumatic stress research is increasingly global but still strongly dominated by HIC. Important opportunities to build capacity in LMIC appear to be missed. Implications toward more international traumatic stress research are discussed.

13.
Sci Rep ; 3: 2426, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23945630

RESUMO

Solid oxide fuel cells (SOFC) are the cleanest, most efficient, and cost-effective option for direct conversion to electricity of a wide variety of fuels. While significant progress has been made in anode materials with enhanced tolerance to coking and contaminant poisoning, cathodic polarization still contributes considerably to energy loss, more so at lower operating temperatures. Here we report a synergistic effect of co-doping in a cation-ordered double-perovskite material, PrBa0.5Sr0.5Co(2-x)Fe(x)O(5+δ), which has created pore channels that dramatically enhance oxygen ion diffusion and surface oxygen exchange while maintaining excellent compatibility and stability under operating conditions. Test cells based on these cathode materials demonstrate peak power densities ~2.2 W cm(-2) at 600°C, representing an important step toward commercially viable SOFC technologies.


Assuntos
Compostos de Cálcio/química , Fontes de Energia Elétrica , Eletrodos , Óxidos/química , Titânio/química , Desenho de Equipamento , Análise de Falha de Equipamento , Temperatura
14.
Int J Clin Exp Pathol ; 5(8): 754-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23071857

RESUMO

BACKGROUND: To evaluate the prognostic implication of cancer stem cell markers in pancreac ductal adenocarcinoma (PDAC), the expression of CD133 and nestin were investigated in a series of PDAC patients in relation to the survival rate. METHODS: This series included 42 cases of PDAC patients and evaluated the stem cell markers CD133 and nestin expression detected by immunohistochemistry. The presence of immunopositive tumor cells considering intensity and area was evaluated and interpreted in comparison to the patients' clinicopathological and survival data. RESULTS: Twenty eight cases (66.7%) showed high CD133 expression. The CD133 expression was mainly identified in the apical border of the tumor cell, but aberrant expression in the cytoplasmic or perinuclear location was also noted. High nestin expression in tumor cells were found in only 2 cases, but high nestin expression along perinuerial or stromal region was found in 15 cases (35.7%). There was no correlation between CD133, nestin expression and gemcitabine resistance. Statistically significant difference was found in patient survival in N stage (p=0.007), and CD133 expression (p= 0.014) in univariate analysis. Nestin expression wan not statistically significant, but it was helpful to identify the perineurial invasion. In Cox-regression hazard model stratified by age and sex for multivariable analysis, AJCC stage and CD133 were independent prognostic factors for overall survival. CONCLUSIONS: CD133 expression is upregulated in PDAC that is related to poor prognosis, and treatment targeted the CD133 positive cancer/cancer stem cells might be a promising therapeutic strategy for this patients.


Assuntos
Antígenos CD/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Glicoproteínas/metabolismo , Proteínas de Filamentos Intermediários/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Pancreáticas/metabolismo , Peptídeos/metabolismo , Antígeno AC133 , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , Nestina , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/mortalidade , Prognóstico , República da Coreia/epidemiologia , Taxa de Sobrevida , Regulação para Cima
15.
Shinrigaku Kenkyu ; 83(5): 440-9, 2012 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-23379082

RESUMO

The present study focused on attitudes related to inhibiting spousal disclosure about stress as an influential factor for the mental health of firefighters. In a pilot study using semi-structured interviews (N = 14), we found that some firefighters usually did not talk about their stresses with their spouses. Some reasons were that they were hiding their weakness, were feeling sure of controlling their stress, out of consideration for their spouse, were giving up on the possibility for improving the situation after spousal disclosure, or hoped to distract themselves. In a subsequent questionnaire survey (N = 554), the results showed that attitudes about inhibiting spousal disclosure of stress have an effect on spousal disclosure about stress and the mental health of firefighters. The findings of the present study imply that spousal disclosure about interpersonal stress can be regarded as an effective factor, along with the disclosure to colleagues, for relieving stress. It is necessary to consider the importance of attitudes about inhibiting disclosure for stress as part of stress management for firefighters.


Assuntos
Atitude , Bombeiros/psicologia , Cônjuges , Estresse Psicológico/psicologia , Adulto , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Projetos Piloto
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