A Discovery of Strong Metal-Support Bonding in Nanoengineered Au-Fe3O4 Dumbbell-like Nanoparticles by in Situ Transmission Electron Microscopy.

The strength of metal-support bonding in heterogeneous catalysts determines their thermal stability, therefore, a tremendous amount of effort has been expended to understand metal-support interactions. Herein, we report the discovery of an anomalous "strong metal-support bonding" between gold nanoparticles and "nano-engineered" Fe3O4 substrates by in situ microscopy. During in situ vacuum annealing of Au-Fe3O4 dumbbell-like nanoparticles, synthesized by the epitaxial growth of nano-Fe3O4 on Au nanoparticles, the gold nanoparticles transform into the gold thin films and wet the surface of nano-Fe3O4, as the surface reduction of nano-Fe3O4 proceeds. This phenomenon results from a unique coupling of the size-and shape-dependent high surface reducibility of nano-Fe3O4 and the extremely strong adhesion between Au and the reduced Fe3O4. This strong metal-support bonding reveals the significance of controlling the metal oxide support size and morphology for optimizing metal-support bonding and ultimately for the development of improved catalysts and functional nanostructures.

Highly Stable Bimetallic AuIr/TiO2 Catalyst: Physical Origins of the Intrinsic High Stability against Sintering.

It has been a long-lived research topic in the field of heterogeneous catalysts to find a way of stabilizing supported gold catalyst against sintering. Herein, we report highly stable AuIr bimetallic nanoparticles on TiO2 synthesized by sequential deposition-precipitation. To reveal the physical origin of the high stability of AuIr/TiO2, we used aberration-corrected scanning transmission electron microscopy (STEM), STEM-tomography, and density functional theory (DFT) calculations. Three-dimensional structures of AuIr/TiO2 obtained by STEM-tomography indicate that AuIr nanoparticles on TiO2 have intrinsically lower free energy and less driving force for sintering than Au nanoparticles. DFT calculations on segregation behavior of AuIr slabs on TiO2 showed that the presence of Ir near the TiO2 surface increases the adhesion energy of the bimetallic slabs to the TiO2 and the attractive interactions between Ir and TiO2 lead to higher stability of AuIr nanoparticles as compared to Au nanoparticles.

Social mobility and psychiatric disabilities: an assessment of the social causation and social selection hypotheses.

Social mobility is the movement of individuals, families and groups from one social position to another. Researchers indicate that people with psychiatric disabilities tend to come from lower socioeconomic status groups, and that the causal relationship between lower socioeconomic status and mental illness occurs through social mobility process. The purpose of this study was to examine the occupational social mobility process of a sample of self-identified psychiatrically disabled individuals who have been active members of the labor force for most of their adult lives. A total of 200 participants were recruited from the customers of a One-Stop Career Center in Gloucester County, New Jersey. The social mobility pattern of persons with psychiatric disabilities was compared to that of persons without psychiatric disabilities (n = 100 for each group). That is, the social selection and the social causation hypotheses were applied to the social mobility patterns of people with psychiatric disabilities. It was revealed that the social class distribution for fathers of people with psychiatric disabilities was not different from that of people without psychiatric disabilities and also there was no significant social mobility difference between the two groups. These findings do not support the social causation and the social selection hypotheses. Specifically, the findings demonstrate that occupational capabilities and skills of people with psychiatric disabilities have been stabilized and are similar to those of people without psychiatric disabilities. Furthermore, these results may dispute several biases and prejudices with regard to social mobility process of persons with psychiatric disabilities.

Validity and reliability of the Frenchay Activities Index for community-dwelling elderly in South Korea.

The speed of population aging in South Korea is projected as the fastest in the world, and a long-term care insurance law has been just enacted. Therefore, it is important to estimate the number of the disabled community-dwelling elderly in South Korea. The Frenchay Activities Index (FAI) is a scale to measure higher level of physical function or activities that are necessary for independence in the community, i.e., instrumental activities of daily living (IADL). The FAI has undergone the most intensive evaluation, but there are only a few studies to establish its validity and reliability for community-dwelling elderly. In addition, a Korean version of the FAI has not been developed yet. The purpose of this study was to develop a Korean version of the FAI and analyze the related factors with IADL, using data from 770 community-dwelling elderly people in Deajeon, Korea. In the results, the reliability was acceptable (Cronbach's alpha coefficient = 0.796). The content and discriminative validity were found to be satisfactory. In the results of the factor analysis, a reasonable four-component solution (domestic chores, outdoor work, leisure and hobby) was found. The related factors to IADL were age, gender, education level, and living conditions. The present findings suggest that the Korean version of the FAI would be useful as a measure of IADL and the results of the factor analysis might reflect socio-cultural differences, such as illiteracy, low socioeconomic level, and sex roles of the Korean elderly.

Physical Exercise with Multicomponent Cognitive Intervention for Older Adults with Alzheimer's Disease: A 6-Month Randomized Controlled Trial.

AIMS: This study aimed to investigate the effect of 6-month physical exercise with a multicomponent cognitive program (MCP) on the cognitive function of older adults with moderate to severe Alzheimer's disease (AD). METHODS: We included 33 participants with AD in a 6-month randomized controlled trial. The intervention group participated in physical exercise and received a MCP. The control group received only the MCP. Before and after the intervention, cognitive outcomes were assessed using the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-cog), Mini-Mental State Examination, and the Clock Drawing Test. Physical performance was evaluated by exercise time, the number of pedal rotation, total load, grip strength, and the Berg Balance Scale (BBS). RESULTS: In all cognitive measures, there were no significant improvements between the two groups after 6 months in the baseline value-adjusted primary analysis. However, the ADAS-cog score was significantly lower between the two groups in secondary analysis adjusted for baseline value, age, sex, and education years. All physical outcomes were significantly higher in the intervention group except for total load compared with baseline measurements. CONCLUSION: This study indicates that it is possible to improve cognitive function in older adults with moderate to severe AD through 6-month physical exercise with a multicomponent cognitive intervention.

Secondary signal imaging (SSI) electron tomography (SSI-ET): A new three-dimensional metrology for mesoscale specimens in transmission electron microscope.

We have demonstrated a new electron tomography technique utilizing the secondary signals (secondary electrons and backscattered electrons) for ultra thick (a few µm) specimens. The Monte Carlo electron scattering simulations reveal that the amount of backscattered electrons generated by 200 and 300keV incident electrons is a monotonic function of the sample thickness and this causes the thickness contrast satisfying the projection requirement for the tomographic reconstruction. Additional contribution of the secondary electrons emitted from the edges of the specimens enhances the visibility of the surface features. The acquired SSI tilt series of the specimen having mesoscopic dimensions are successfully reconstructed verifying that this new technique, so called the secondary signal imaging electron tomography (SSI-ET), can directly be utilized for 3D structural analysis of mesoscale structures.

Migration of Single Iridium Atoms and Tri-iridium Clusters on MgO Surfaces: Aberration-Corrected STEM Imaging and Ab Initio Calculations.

To address the challenge of fast, direct atomic-scale visualization of the migration of atoms and clusters on surfaces, we used aberration-corrected scanning transmission electron microscopy (STEM) with high scan speeds (as little as ∼0.1 s per frame) to visualize the migration of (1) a heavy atom (Ir) on the surface of a support consisting of light atoms, MgO(100), and (2) an Ir3 cluster on MgO(110). Sequential Z-contrast images elucidate the surface transport mechanisms. Density functional theory (DFT) calculations provided estimates of the migration energy barriers and binding energies of the iridium species to the surfaces. The results show how the combination of fast-scan STEM and DFT calculations allow visualization and fundamental understanding of surface migration phenomena pertaining to supported catalysts and other materials.

Construct validity of the Frenchay Activities Index for community-dwelling elderly in Japan.

Many researchers have developed various measures to evaluate the functional status of community-dwelling elderly. The Frenchay Activities Index (FAI) was developed to measure instrumental activities of daily living in stroke populations. The FAI has undergone the most intensive evaluation, but its factor structure has not been examined in Japan. The primary purpose of this study was to investigate the construct validity of the FAI for non-stroke community-dwelling elderly in Japan. The study subjects were 1,323 randomly selected community older residents in Hojo city, Ehime prefecture, the southern part of Japan. In order to investigate the construct validation, we performed factor analyses, i.e., exploratory factor analysis and confirmatory factor analysis. Furthermore, we examined the influences of age and gender on the FAI constructs. In the results, the FAI had a two-factor structure consisting of domestic chores, including washing clothes and preparing meals, and work and leisure, including gardening, driving and outings. Younger age was significantly related to increased performance on both factors. In addition, relative to females, males had a lower performance on the domestic chores and a greater performance on the work and leisure. These results suggest that the FAI satisfies the construct validity in the Japanese community-dwelling elderly. The FAI and its two factors provide important and clinically valuable information for understanding the patterns of functional status in the Japanese community-dwelling elderly.

Validity and utility of the Craig Hospital Inventory of Environmental Factors for Korean community-dwelling elderly with or without stroke.

The social environmental barriers are considered to be important because the "social participation" of people with impairments would be facilitated by the prevention and reduction of environmental barriers. The Craig Hospital Inventory of Environmental Factors (CHIEF) is one of the few scales to assess the environmental barriers. In this study, we developed the Korean version of CHIEF and evaluated its construct validity and utility in a sample of Korean community-dwelling elderly with or without stroke. We evaluated the construct validity of the CHIEF by testing the original five-factor structure using a confirmatory factor analysis in 400 elderly in Seoul, Korea. The utility of the CHIEF was then assessed by examining the relationships between individual characteristics, Barthel Index and perceived environmental barriers, measured by the CHIEF, using a structural equation modeling approach. The confirmatory factor analysis result demonstrated the validity of a second-order factor model of the CHIEF comprising the five factors as first-order factors. The perceived environmental barrier was a second-order factor when provided acceptable fit indices after two modifications. The structural equation modeling indicates that perceived environmental barriers are significantly related to activities of daily life but not age, gender, and the episode of stroke. The CHIEF is useful in measuring environmental factors for Korean older adults with or without stroke.

Development of the Korean version of Short-Form 36-Item Health Survey: health related QOL of healthy elderly people and elderly patients in Korea.

The health-related QOL (HRQOL) has been used extensively in clinical and epidemiological research and health service studies. Especially, the Medical Outcome Study Short-form 36-Item Health Survey (SF-36) is a widely used health status measure. However, a Korean version has not been developed and tested yet. The purpose of this study was to develop a Korean version of the Short-form Health Survey (SF-36) for use in health related quality of life measurements for Korean elderly people. SF-36 data from 90 healthy elderly people using Social Education Service and 120 elderly patients using a day care service in Seoul, Korea, were examined. We translated SF-36 version 2.0 into Korean and assessed its reliability and validity. In the results, the content validity and discriminant validity were found to be satisfactory. Cronbach's alpha coefficients ranged from 0.9298 to 0.9383. The test-retest reliability coefficients ranged from 0.710 to 0.895. In addition, the utility was examined by testing the correlation between the health-related QOL and related factors (sex, age, motor function, ability of daily life) among the elderly people. The present findings suggested that the Korean version of SF-36 would be useful as a measure of the health related QOL in Korean elderly people.

Development and construct validation of the Korean competence scale (KCS).

A comprehensive Korean competence scale (KCS) designed for Korean older adults, was developed and its construct validity evaluated. KCS assesses their higher levels of functional competence than activities of daily livings (ADL), necessary for independence in the home and community. The internal structure of the scale was tested using an exploratory and confirmatory factor analysis with two elderly Korean sample groups. As expected, the exploratory factor analysis result demonstrated a three-factor solution comprised of the following three domains: instrumental self-maintenance, intellectual activity, and social role. The confirmatory factor analysis results showed that an acceptable solution could be estimated for a second-order factor model comprised of these factors. These findings provide evidence for the construct validity of the instrument and have implications for future research on factorial invariance.