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For the hospital administration, 1 major responsibility is to prevent the outflow of existing patients and minimize losses because of the failure of patients with cancer to attend appointments. We analyzed the association between no-show rates and characteristics of patients with cancer at a tertiary hospital in Seoul using patient affair data. Among the 680 190 patients, no-show rates were 4.39% and 3.37% for males and females, respectively. Male patients with colon and rectum, pancreas, and liver cancer had higher no-show rates (5.81%, 5.8%, and 5.1%). Among females, pancreas, colon and rectum, and liver cancer were associated with high no-show rates (5.65%, 5.44%, and 4.92%). For both males and females, liver (males: OR = 2.02; 95% CI: 1.68-2.44; females: OR = 1.91; 95% CI: 1.60-2.28) and pancreas (males: OR = 1.98; 95% CI: 1.57-2.50; females: OR = 1.97; 95% CI: 1.61-2.42) cancer were associated with high no-show rates. To reduce the rate of no-shows, hospitals should establish and enforce "missed appointment" policies as well as its effect upon health outcome.

Purpose Internet addiction has emerged as a major public health problem worldwide. In November 2011, the South Korean government implemented an online game shutdown policy, lasting from 12:00 to 6:00 am, as a means of preventing Internet addiction in adolescents aged 15 or below. This study analyzed the effect of this shutdown policy on adolescent Internet use, addiction, and sleeping hours. Methods We analyzed data collected from the Korea Youth Risk Behavior Web-based Survey from 2011 to 2015. Respondents were divided into two groups by age: aged 15 or below (male = 76,048, female = 66,281) and aged 16 or above (male = 52,568, female = 49,060). A difference-in-difference analysis was used to evaluate the effect of this shutdown policy. Results In 2012, which is immediately following policy enforcement, daily amount of Internet use (in minutes) decreased more in adolescents affected by the policy (i.e., the aged 15 or below group). However, it steadily increased in 2013, 2014, 2015, and showed no meaningful long-term improvements 4 years after policy implementation (−3.648 minutes in 2012 [ p = .001], −3.204 minutes in 2013 [ p = .011], −1.140 minutes in 2014 [ p = .384], and 2.190 minutes in 2015 [ p = .107]). The shutdown policy did not alter Internet addiction or sleeping hours. Interestingly, female adolescents, adolescents with low academic performance, and adolescents with low exercise levels exhibited comparatively stronger and longer lasting initial declines in Internet usage. Conclusions The shutdown policy had practically insignificant effects in reducing Internet use for target adolescents. Thus, policymakers aiming to reduce or prevent Internet addiction should use different strategies.

Objectives Despite an increase in the female work force and recent increase in childhood obesity, the association between working hours of mothers and childhood obesity as well as how such association differs according to mothers’ weight and intake frequency of energy-dense, nutrition-poor (EDNP) foods remain unclear. Methods Data from the Korean National Health and Nutrition Examination Survey (2008–2012) that included samples from 3914 children in 2526 households were analyzed. Two-level (household-children) mixed-effects modeling was performed to investigate the association between mothers’ working hours and childhood obesity based on body mass index (BMI) and waist circumference (WC). Results Long working hours (h) of mothers were associated with both BMI (β = − 0.14; P = 0.324 for 1–20 h, β = 0.10; P = 0.334 for ≤ 21–40 h; β = 0.09; P = 0.429 for 41–68 h, β = 0.51; P = 0.015 for ≥ 69 h) and WC of the child (β = 0.06; P = 0.809 for 1–20 h; β = 0.46; P = 0.017 for ≤ 21–40 h; β = 0.59; P = 0.004 for 41–68 h, β = 1.35; P

Organophosphate pesticides (OPPs) are one of the most widely used insecticides. OPPs exert their neurotoxic effects by inhibiting acetylcholine esterase (AChE). Most of the gross developmental abnormalities observed in OPP-treated fish, on the other hand, may not be explained solely by AChE inhibition. To understand the overall molecular mechanisms involved in OPP toxicity, we used the zebrafish (ZF) model. We exposed ZF embryos to an OPP, phosmet, for 96 h, and then analyzed developmental abnormalities and performed whole transcriptome analysis. Phenotypic abnormalities, such as bradycardia, spine curvature, and growth retardation, were observed in phosmet-treated ZF (PTZF). Whole transcriptome analysis revealed 2190 differentially expressed genes (DEGs), with 822 and 1368 significantly up-and downregulated genes, respectively. System process and sensory and visual perception were among the top biological pathways affected by phosmet toxicity. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed significant enrichment of metabolic pathways, calcium signaling pathway, regulation of actin cytoskeleton, cardiac muscle contraction, drug metabolism–other enzymes, and phototransduction. Quantitative real-time PCR results of six DEGs agreed with the sequencing data expression profile trend. Our findings provide insights into the consequences of phosmet exposure in ZF, as well as an estimate of the potential risk of OPPs to off-target species.

Simple Summary Rearing honey bee (Apis mellifera) larvae in vitro is an important method for studying bee larvae diseases or the toxicity of pesticides on bees. Laboratory experiments for bee larvae are usually performed by placing a rearing plate horizontally during all developmental stages. However, recent studies have demonstrated that a horizontal rearing environment can cause the deformation of emerged bees. Most studies adopted a vertical rearing method to reduce such deformation, but there is a lack of information on the emergence rates and deformation rates of bees reared on vertical or horizontal plates. Therefore, in this study, we examined the effect of placing the plates vertically and horizontally on newly emerged bees. There were no significant differences in larval mortality, pupal mortality, and adult emergence rates between horizontal and vertical rearing plates. However, the adult deformation rates of the horizontal plates were significantly higher than those of the vertical plates. In conclusion, we suggest that the vertical rearing method is more suitable when considering the deformation rate of the control group to verify the sublethal effects of pesticides on honey bees. Abstract Rearing honey bee larvae in vitro is an ideal method to study honey bee larval diseases or the toxicity of pesticides on honey bee larvae under standardized conditions. However, recent studies reported that a horizontal position may cause the deformation of emerged bees. Accordingly, the purpose of this study was to evaluate the emergence and deformation rates of honey bee (Apis mellifera ligustica) larvae reared in horizontal and vertical positions. The study was conducted under the same laboratory conditions with three experimental groups, non-capped or capped horizontal plates and capped vertical plates. However, our results demonstrated that the exhibited adult deformation rates of the horizontal plates were significantly higher (27.8% and 26.1%) than those of the vertical plates (11.9%). In particular, the most common symptoms were deformed wings and an abnormal abdomen in the horizontal plates. Additionally, adults reared on horizontal plates were substantially smaller (10.88 and 10.82 mm) than those on vertical plates (11.55 mm). Considering these conclusions, we suggest that a vertical rearing method is more suitable when considering the deformation rates of the control groups to verify the sublethal effects of pesticides on honey bees.

The relationships between breastfeeding discontinuation and cesarean section delivery, and the occurrence of postpartum depression (PPD) remain unclear. Therefore, we aimed to investigate the association of breastfeeding discontinuation and cesarean section delivery with PPD during the first 6 months after delivery.Data were extracted from the Korean National Health Insurance Service-National Sample Cohort for 81,447 women who delivered during 2004-2013. PPD status was determined using the diagnosis code at outpatient or inpatient visit during the 6-month postpartum period. Breastfeeding discontinuation and cesarean section delivery were identified from prescription of lactation suppression drugs and diagnosis, respectively. Cox proportional hazards models were used to calculate adjusted hazard ratios.Of the 81,447 women, 666 (0.82%) had PPD. PPD risk was higher in women who discontinued breastfeeding than in those who continued breastfeeding (hazard ratio=3.23, P0.0001), in women with cesarean section delivery than in those with vaginal delivery (hazard ratio=1.26, P=0.0040), and in women with cesarean section delivery who discontinued breastfeeding than in those with vaginal delivery who continued breastfeeding (hazard ratio=4.92, P0.0001).Study limitations include low PPD incidence; use of indirect indicators for PPD, breastfeeding discontinuation, and working status, which could introduce selection bias and errors due to miscoding; and potential lack of adjustment for important confounders.Breastfeeding discontinuation and cesarean section delivery were associated with PPD during the 6-month postpartum period. Our results support the implementation of breastfeeding promoting policies, and PPD screening and treatment programs during the early postpartum period.

Highly anisometric nanoparticles have distinctive mechanical, electrical, and thermal properties and are therefore appealing candidates for use as self-assembly building blocks. Here, we demonstrate that ultra-anisometric nanoplates, which have a nanoscale thickness but a micrometer-scale edge length, offer many material design capabilities. In particular, we show that these nanoplates "copolymerize" in a predictable way with patchy spheres (Janus and triblock particles) into one- and two-dimensional structures with tunable architectural properties. We find that, on the pathway to these structures, nanoplates assemble into chains following the kinetics of molecular step-growth polymerization. In the same mechanistic framework, patchy spheres control the size distribution and morphology of assembled structures, by behaving as monofunctional chain stoppers or multifunctional branch points during nanoplate polymerization. In addition, both the lattice constant and the stiffness of the nanoplate assemblies can be manipulated after assembly. We see highly anisometric nanoplates as one representative of a broader class of dual length-scale nanoparticles, with the potential to enrich the library of structures and properties available to the nanoparticle self-assembly toolbox.

Objective The aim of this study was to investigate the impact of intensive grandchild care on depressive symptoms among grandparents. Methods We used data from 2008 to 2012 of the Korea Longitudinal Study of Aging. Using the data from 2008 at baseline, data included 5129 individuals aged 50 years and more without depression with at least one grandchild. A generalized estimating equation was used to investigate the impact of intensive grandchild care on depressive symptoms. Investigated factors included the intensity of grandchild care, measured by hours spent caring for a grandchild per week: (i) none (0 h); (ii) non-intensive grandchild care (1–39 h); and intensive grandchild care (≥40 h). Depressive symptoms were measured using the 10-item Center for Epidemiological Studies Depression scale. Results Among 5128 participants from 2008 to 2012, 3.0% were providing non-intensive grandchildren care, and 1.9% were providing intensive grandchild care. Compared with grandparents providing no grandchild care, those who provided intensive grandchild care experienced reduced depressive symptoms (β = −0.51 [p = 0.007] vs. no childcare). Men (β = −1.22 [p = 0.012] vs. no childcare) providing intensive grandchild care experienced a greater reduction in depressive symptoms compared with women (β = −0.44 [p = 0.029] vs. no childcare) providing grandchild care. Grandparents who were receiving financial support from adult children were more likely to experience reduced depressive symptoms than those not receiving such support. Conclusion The results of this study reveal that intensive grandchild care is associated with lower depressive symptoms among older adults, particularly men. The findings emphasize the importance of encouraging older adults to participate in grandchild care, regardless of gender. Copyright © 2016 John Wiley & Sons, Ltd.

ObjectiveThis study aimed to examine the association of employment status and income with self-rated health among waged workers with disabilities in South Korea.MethodsThis study used the Panel Survey of Employment for the Disabled from 2011 to 2015. A total of 951 waged workers with disabilities were selected as baseline subjects in 2011 and were followed up for 5 years. This study used a generalised linear mixed model after adjusting for covariates.ResultsAmong 951 waged workers with disabilities, the results showed that 39.3% of workers with disabilities reported poor self-rated health. Workers with disabilities with a precarious employment status and lower income were 1.22 (95% CI 1.21 to 1.23) and 1.81 (95% CI 1.80 to 1.83) times more likely to have poor self-rated health than those with permanent employment and higher income, respectively. A subgroup analysis found that precarious workers with disabilities in lower income households had higher possibilities of poor self-rated health.ConclusionThis study suggests that precarious employment and lower income of waged workers with disabilities are significantly associated with poor self-rated health compared with those with permanent jobs or higher income.

To investigate the impact of different living arrangements on quality of life (QoL) and health-related quality of life (HRQoL) in the elderly. We used data from the first to fourth wave of the Korean Longitudinal Study of Aging. Using the first wave as a baseline, the data included 5050 individuals aged 60 years and older with at least one living child. QoL and HRQoL were measured using a visual analogue scale developed by the Korean Labor Institute that bears similarity to the EQ-VAS. Living arrangements were categorized based on household composition (single household, one-generation household, two-generation household, and three-generation household) and the marital status of a cohabiting adult child. A generalized estimating equation was used to examine the association between living arrangements and QoL/HRQoL. Compared to elderly individuals living in three-generation families with a married child, those in a single household (QoL: β = −2.67 [P = 0.001]; HRQoL: β = −2.24 [P = 0.007]), those living in a three-generation family with an unmarried adult child (QoL: β = −5.19 [P

Background: There are no studies researching the relationship between house-poor persons and mental health. Therefore, this study aimed to investigate the relationship between house-poor status and depressive symptoms. Aim: To examine the relationship between the house-poor and depressive symptoms according to household income. Methods: Data from the Korean Welfare Panel Study were used. House-poor were defined as people having possession with over 10% house-related interest in disposable income. About 7,565 participants over the age of 19 years were followed up from 2011 to 2013. The generalized estimating equations were used for analysis. Results: Individuals with more house-related debt showed increasingly higher depression scores (possession with under 5% related debt to disposable income β = 0.2024, p = .1544; under 10% β = 0.7030, p = .0008; over 10% β = 1.3207, p Conclusion: Individuals without houses and individuals owning houses with higher percentages of house-related interests showed higher levels of depressive symptoms. Therefore, this study affirmed that the importance of considering the most vulnerable groups in addressing the mental health of individual.

The number of cancer survivors is increasing as a consequence of improved therapeutic options. Many families are suffering from the resultant financial burden. Our study aims to determine the total medical cost for 5 years after the initial diagnosis of childhood cancers. A customized dataset from the Korean National Health Insurance Claims Database was requested for this study. A total of 7317 patients were selected to determine the total medical cost. The costs are presented as the 2% trimmed mean value to exclude extreme costs. The medical costs were further classified according to cancer type, treatment phase, and socioeconomic status. Multiple linear regression analyses were performed. The average total medical cost per patient is 36.8 million Korean Wons or 32,157 United States Dollars. Analysis of socioeconomic status revealed that the higher income group demonstrated higher medical expenditure when compared to other groups. Analysis of the treatment phase showed that costs associated with the early phase of treatment are the highest, especially in the first 3 months after initial diagnosis. To alleviate the financial burden and reduce the socioeconomic disparities associated with medical care and costs, a better understanding of the current experience of patients and their families is required.

This study aims to investigate the association between family dinners involving the participation of both mother and her adolescent child and depressive symptoms within the adolescents. Data from 2183 mother&ndash, child pairs obtained from the Korea National Health and Nutrition Examination Survey IV&ndash, VI (2010&ndash, 2013, and 2015) were employed in the analysis. The dependent variable of this study was depressive symptom of adolescents. Maternal accompaniment at family dinners was the variable of interest. Logistic regression analysis was performed to calculate odds ratios (ORs) and 95% confidence intervals (CI) to analyze the association between family dinners including both mother and adolescent and depressive symptoms within the adolescent. According to the results, maternal absence in family dinners was significantly associated with higher odds of depressive symptoms in adolescents (OR = 1.42, 95%CI: 1.01&ndash, 1.99). In particular, the association was strong among adolescents aged 12&ndash, 15, female adolescents, those with mothers without depressive symptoms, and city dwellers. This study showed that maternal absence at family dinners was strongly associated with depressive symptoms of adolescents. For the sake of adolescent mental health, it may be necessary to consider the implementation of policies that emphasize the importance of maternal accompaniment at family dinners and encourage the presence of mothers at the dinner table.

Reconfigurable hybrid nanoparticles made by decorating flexible polymer shells on rigid inorganic nanoparticle cores can provide a unique means to build stimuli-responsive functional materials. The polymer shell reconfiguration has been expected to depend on the local core shape details, but limited systematic investigations have been undertaken. Here, two literature methods are adapted to coat either thiol-terminated polystyrene (PS) or polystyrene-poly(acrylic acid) (PS-b-PAA) shells onto a series of anisotropic gold nanoparticles of shapes not studied previously, including octahedron, concave cube, and bipyramid. These core shapes are complex, rendering shell contours with nanoscale details (e.g., local surface curvature, shell thickness) that are imaged and analyzed quantitatively using the authors' customized analysis codes. It is found that the hybrid nanoparticles based on the chosen core shapes, when coated with the above two polymer shells, exhibit distinct shell segregations upon a variation in solvent polarity or temperature. It is demonstrated for the PS-b-PAA-coated hybrid nanoparticles, the shell segregation is maintained even after a further decoration of the shell periphery with gold seeds; these seeds can potentially facilitate subsequent deposition of other nanostructures to enrich structural and functional diversity. These synthesis, imaging, and analysis methods for the hybrid nanoparticles of anisotropically shaped cores can potentially aid in their predictive design for materials reconfigurable from the bottom up.

We report the isolation of a nonporous plate-like intermediate species (MOF-i) obtained during the synthesis of MOF-5 and the testing of this intermediate’s reactivity toward three metal ions (ZnII, CuII, and MnII) in N,N-dimethylformamide at 120 °C. We obtained interpenetrated MOF-5 crystals from the reaction between MOF-i and Zn(NO3)2·6H2O, accompanied by a change in morphology from a plate to a cube. Reaction with CuCl2·2H2O did not disrupt the plate-like morphology of MOF-i, but it did result in the replacement of ZnII by CuII and formation of a novel porous copper MOF. MOF-i showed no reactivity toward MnCl2. Our results demonstrate that MOF-i imparts a selective reactivity that is different from the individual metal ions employed in conventional synthesis of MOFs and suggests that reactive intermediates may be useful in extending the diversity of metal–organic frameworks.

Background The risk of pressure ulcers in beneficiaries of long-term care insurance is expected to increase in South Korea's aging society. However, those who stay at home may not be managed appropriately with regard to pressure ulcer development. Here, we examined the relationship between home-visit nursing services and hospitalization related to pressure ulcers among beneficiaries with pressure ulcers in home-care settings. Methods We analyzed National Aging Cohort data from 2008 to 2013. The study population was defined as those who required nursing care for pressure ulcers and received home-care services at least once under long-term care insurance. Logistic regression analysis using generalized estimating equation models was performed to examine the association between home-visit nursing services and hospitalization related to pressure ulcers. Results Among 4,807 beneficiaries with pressure ulcers, 859 (17.9%) were admitted to hospitals during the study period. The use of home-visit nursing services was associated significantly with a lower risk of hospitalization (odds ratio = 0.68, 95% confidence interval = 0.49-0.93; reference, no use). This association was especially strong in beneficiaries with mildly impaired mobility and cognitive function. Conclusions Given the protective role of home-visit nursing services in the management of long-term care insurance beneficiaries with pressure ulcers who stay at home, healthcare professionals need to consider effective strategies for the activation of home-visit nursing services in South Korea.

The shape anisotropy of nanoparticle building blocks is of critical importance in determining their packing symmetry and assembly directionality. While there has been extensive research on the effect of their overall geometric shapes, the importance of nanometer morphology details is not well-recognized or understood. Here we draw on shape-anisotropic gold triangular nanoprism building blocks synthesized based on a method we recently developed; besides the "large-scale" triangular prism shape (79.8 nm in side length and 22.0 nm in thickness), the prisms are beveled with their sides convexly enclosed by two flat {100} facets. We engineer the balance between electrostatic repulsion and entropically driven depletion attraction in the system to generate self-assemblies without or with the effect of the nanoscale beveling detail. A conventional, planar honeycomb (p-honeycomb) lattice forms with the triangular basal planes packed on the same plane at low depletion attraction, whereas an unexpected interlocking honeycomb (i-honeycomb) lattice and its "supracrystal" forms are assembled with additional close-paralleling of side facets at high depletion attraction. The i-honeycomb lattice renders all the metallic surfaces in close proximity and leads to a surface-enhanced Raman scattering signal nearly 5-fold higher than that in the p-honeycomb lattice and high sensitivity for detecting the model molecule Rhodamine 6G at a concentration as low as 10

Objective To assess whether type of long-term care service is a risk factor of the incidence of pressure ulcers among older adults with dementia who are receiving long-term care insurance (LTCI). Methods Data from LTCI beneficiaries (benefit level 1 or 2) with dementia, aged 60 and older (n = 7841), in the Korean Elderly Cohort data set from 2008 to 2013 were used. Type of long-term care service was categorized into home or institutional care using the LTCI Claims Database. The National Health Insurance Claims Database was used to identify the incidence of pressure ulcers as the outcome variable in a survival analysis using the time-dependent Cox proportional hazard model. Results Of the 7841 participants, 98 (1.2%) exhibited pressure ulcers. Compared with beneficiaries receiving home care, those receiving institutional care had a higher adjusted hazard ratio for pressure ulcers (hazard ratio 6.48, 95% confidence interval 3.48–10.86). These associations were particularly strong among beneficiaries without pressure ulcers during the mandatory assessment for benefit eligibility and who were partially ambulatory. Discussion Beneficiaries receiving institutional care were more likely to have pressure ulcers than were those receiving home care. The government must monitor the quality of institutional long-term care services and encourage service providers to improve such care.

Men and women participantsâ general characteristics. * Number of chronic diseases: Hypertension, dyslipidemia, stroke, myocardial infarction, angina, arthritis, rheumatoid arthritis, asthma, thyroid gland disorder, chronic renal failure, hepatitis B. * Number of chronic diseases: Hypertension, dyslipidemia, stroke, myocardial infarction, angina, arthritis, rheumatoid arthritis, asthma, thyroid gland disorder, chronic renal failure, hepatitis B. Table S2. Subgroup analysis of sitting-time and major depressive disorder according to physical activity. Adjusted for age, household income level, educational level, marital status, occupation, obesity, current smoking status, alcohol use and number of chronic diseases. (DOCX 51Â kb)

This study, the exchange value of the car after the repair, which affects the valuation elements and repair characteristics factors were investigated. Based on this specific accident damaged condition of the car, repair range, repair methods, repair costs, market transactions, taking into account the vehicle`s depreciation appraisal method is proposed.

A dinuclear zinc complex containing both a σ-dimerized 7,7,8,8-tetracyanoquinodimethane (TCNQ) ligand ([TCNQ-TCNQ](2-)) and TCNQ(-) was synthesized for the first time. This is the first instance of a single molecular complex with a bridging [TCNQ-TCNQ](2-) ligand. Each zinc center is coordinated with two 2,2'-bipyrimidines and one TCNQ(-), and the remaining coordination site is occupied by a [TCNQ-TCNQ](2-) ligand, which bridges the two zinc centers. The complex facilitates π-stacking of TCNQ(-) ligands when crystallized, which gives rise to a near-IR charge-transfer transition and strong antiferromagnetic coupling.

This study optimizes the profile of the diaphragms of the pressure pulsation damper structure in a high-pressure GDI pump system that is now under development by applying the design of experiments (DOE) method. Because a high-pressure pulsation ranging from 0 to 10 bar reduces the performance of a GDI engine and harms it from a structural point of view, attenuating the large amplitude of the fluid pulsation pressure of the gasoline fuel injected into a GDI pump is necessary. Both the relatively low frequency range of the pressure pulsation, i.e., from 0 Hz to 30 Hz, inside the GDI engine and the high pressure of the utilized gasoline fuel prevent us from applying the existing pressure pulsation dampers such as a T-filter and Helmholtz resonator. Therefore, automotive companies utilize a new pressure pulsation damper structure called an accumulator, which is filled with gas. In the development of this pressure accumulator, it is crucial to design optimal profiles for the enveloping diaphragms in terms of the pulsation efficiency and mechanical stress for the sake of safety. In order to optimize the profile of the diaphragms used in the accumulator developed for a GDI engine, this research develops a new finite element procedure that considers the pressure variation by assuming the isoenthalpy state of the enveloped gas inside the accumulator. The developed finite element procedure is then integrated with the DOE method to determine the optimal profile for the enveloping structure of the developed accumulator. To validate the performance of the developed accumulator, the optimized accumulator is manufactured and tested.

Oviparous fishes are known to possess two types of aromatase, which are ovary type (cyp19a1a) and brain type (cyp19a1b). These aromatases play important roles in the reproduction of oviparous fish. However, little information is available on the role of aromatases in the reproduction of viviparous fish. This study has been carried out to examine the changes of aromatase gene expression prior to and during vitellogenesis and during gestation in a marine viviparous fish, black rockfish, Sebastes schlegelii. The coding sequence of cyp19a1b gene cloned from rockfish brain was 1497 nucleotides (nt). Rockfish cyp19a1b was more similar to cyp19a1b from other fish species than to rockfish cyp19a1a in amino acid sequence. In addition, phylogenetic analysis showed that aromatases of this viviparous rockfish were more similar to those of oviparous fishes than those of viviparous mammals. Cyp19a1a mRNA was expressed most strongly in the ovary and weakly in the testis, brain, and spleen. Cyp19a1b mRNA was det...

We use liquid-phase transmission electron microscopy (LP-TEM) to characterize the structure and dynamics of a solution-phase superlattice assembled from gold nanoprisms at the single particle level. The lamellar structure of the superlattice, determined by a balance of interprism interactions, is maintained and resolved under low-dose imaging conditions typically reserved for biomolecular imaging. In this dose range, we capture dynamic structural changes in the superlattice in real time, where contraction and smaller steady-state lattice constants are observed at higher electron dose rates. Quantitative analysis of the contraction mechanism based on a combination of direct LP-TEM imaging, ensemble small-angle X-ray scattering, and theoretical modeling allows us to elucidate: (1) the superlattice contraction in LP-TEM results from the screening of electrostatic repulsion due to as much as a 6-fold increase in the effective ionic strength in the solution upon electron beam illumination; and (2) the lattice constant serves as a means to understand the mechanism of the in situ interaction modulation and precisely calibrate electron dose rates with the effective ionic strength of the system. These results demonstrate that low-dose LP-TEM is a powerful tool for obtaining structural and kinetic properties of nanoassemblies in liquid conditions that closely resemble real experiments. We anticipate that this technique will be especially advantageous for those structures with heterogeneity or disorder that cannot be easily probed by ensemble methods and will provide important insight that will aid in the rational design of sophisticated reconfigurable nanomaterials.

Background Quality of life (QoL) in old age is of major importance because the global population is aging rapidly. Offspring support, including financial and emotional support, is important in later life and directly affects the wellbeing of elderly individuals. The aim of this study was to examine the relationship between QoL in older parents and offspring support. Methods We used baseline data from the 2006–2012 Korean Longitudinal Study of Aging, from 3,274 individuals aged 65 years or older. We measured the individual’s QoL using a visual analog scale and included both relationship satisfaction and regular economic support as variables. A generalized estimating equation (GEE) model was used to perform longitudinal regression analysis on the data. Results Regarding the QoL of older parents, those with an unsatisfying relationship with their offspring had a QoL of -21.93 (SE = 0.55; P

Background The aim of this study is to examine the association between parental socioeconomic status (SES) and the experience as well as treatment of dental caries among children aged 9 to 18 years. Methods Data from 1253 children aged 9–18 years from the Korean National Health and Nutrition Examination Survey (2012–2013) were analyzed. Parental socioeconomic status was measured using household income level and maternal educational level. The decayed, missing, and filled teeth (DMFT) index was used to measure experience of dental caries (DMFT ≥ 1). Non-treatment of dental caries was measured according to whether the participants who experienced dental caries used a dental service at a dental clinic to treat caries during the previous year. Logistic regression was used to investigate the association between parental socioeconomic status and the experience of dental caries as well as the association between parental socioeconomic status and the non-treatment of dental caries among children that have experienced caries. Results A total of 808 subjects (64.5 %) experienced dental caries among 1253 participants, and 582 of these 808 subjects (72.0 %) did not receive treatment among those having experience of dental caries. Parental socioeconomic status was not associated with experience of dental caries. However, those from low- and middle-income households were less likely to receive treatment than those from high-income households (odds ratio [OR] 2.11 [95 % confidence interval (CI) 1.16–3.86], OR 2.14 [95 % CI 1.27–3.62]). In particular, those from low- and middle-income households who had regular dental checkups were more likely to have untreated caries than those from high-income households (OR 3.58 [95 % CI 1.25–10.24]). Conclusions This study demonstrates the parental household income–related disparities in children’s dental health treatment. Efforts should be made to lower financial barriers to dental health services, particularly among those from low-income households, in order to reduce dental health disparities in the treatment of caries in children.

Background Previous studies have examined associations between sitting time and negative health outcomes and mental health. However, the relationship between overall sitting time and major depressive disorder (MDD) in South Korea has not been studied. This study examined the association between MDD and overall sitting time and physical activity in South Koreans. Methods Data from the sixth Korean National Health and Nutrition Examination Survey (KNHANES), a cross-sectional, nationally representative survey, were analyzed. Total participants were 4145 in 2014. MDD was assessed using the Patient Health Questionnaire (PHQ-9). Participants’ data regarding self-reported sitting time and physical activity were analyzed via multiple logistic regression. Results Results showed that people who sat for 8–10 h (OR: 1.56, 95% CI: 1.15–2.11) or more than 10 h (OR: 1.71, 95% CI: 1.23–2.39) had increased risk of MDD compared to those who sat for less than 5 h a day. Subgroup analysis showed that the strongest effect of reported sitting time on risk of MDD was found in men with lower levels of physical activity who sat for 8 to 10 h (OR: 3.04, 95% CI: 1.15–8.01) or more than 10 h (OR: 3.43, 95% CI: 1.26–9.35). Level of physical activity was not an independent predictor for MDD. Conclusions Sitting for long periods was associated with greater risk of MDD in South Korean adults. Reducing sitting time in people with MDD could help to prevent associated physical health problems and may improve mental health. Electronic supplementary material The online version of this article (doi:10.1186/s12888-017-1439-3) contains supplementary material, which is available to authorized users.

The aim of this study was to investigate the impact of intensive grandchild care on depressive symptoms among grandparents.We used data from 2008 to 2012 of the Korea Longitudinal Study of Aging. Using the data from 2008 at baseline, data included 5129 individuals aged 50 years and more without depression with at least one grandchild. A generalized estimating equation was used to investigate the impact of intensive grandchild care on depressive symptoms. Investigated factors included the intensity of grandchild care, measured by hours spent caring for a grandchild per week: (i) none (0 h); (ii) non-intensive grandchild care (1-39 h); and intensive grandchild care (≥40 h). Depressive symptoms were measured using the 10-item Center for Epidemiological Studies Depression scale.Among 5128 participants from 2008 to 2012, 3.0% were providing non-intensive grandchildren care, and 1.9% were providing intensive grandchild care. Compared with grandparents providing no grandchild care, those who provided intensive grandchild care experienced reduced depressive symptoms (β = -0.51 [p = 0.007] vs. no childcare). Men (β = -1.22 [p = 0.012] vs. no childcare) providing intensive grandchild care experienced a greater reduction in depressive symptoms compared with women (β = -0.44 [p = 0.029] vs. no childcare) providing grandchild care. Grandparents who were receiving financial support from adult children were more likely to experience reduced depressive symptoms than those not receiving such support.The results of this study reveal that intensive grandchild care is associated with lower depressive symptoms among older adults, particularly men. The findings emphasize the importance of encouraging older adults to participate in grandchild care, regardless of gender. Copyright © 2016 John WileySons, Ltd.

Physical properties of κ- and e-Ga2O3 are investigated using density functional theory. We utilized the supercell method considering the partial occupancies in e-Ga2O3. The polarization values of these materials were analyzed to overcome the inconsistency between experimental and theoretical studies. The polarization values of κ- and e-Ga2O3 were ~26.39 and 24.44 µC/cm2, respectively. The bandgap values of 4.62 and 4.27 eV were estimated with the hybrid functional method, which suggested an underestimation of the PBEsol functional values of 2.32 and 2.06 eV for κ- and e-Ga2O3, respectively.

Two types of composite materials composed of Pt and WC1−x nanoparticles supported on multiwalled carbon nanotubes (MWNT) are synthesized and evaluated in terms of their electrochemical properties, especially for the hydrogen oxidation reaction (HOR). The Pt nanoparticles are prepared by reduction of H2PtCl6 with NaBH4, and the WC1−x nanoparticles by a sonochemical method with a W(CO)6 precursor. One of the composites is synthesized by forming WC1−x nanoparticles on Pt-loaded MWNT and the other by physically mixing Pt-loaded MWNT with WC1−x-loaded MWNT. The sonochemical synthesis of WC1−x on Pt-loaded MWNT forms WC1−x preferentially on Pt nanoparticles, which makes intimate contact between WC1−x and Pt nanoparticles. The cyclic voltammograms of these composite materials show evidences for H+-spill-over from Pt to WC1−x, thereby increasing the electrochemically active surface area (ECA). The composite in which WC1−x is deposited on Pt shows a remarkable increase in ECA probably because the intimate contact between WC1−x and Pt enhances the H+-spill-over. These materials exhibit enhanced HOR characteristics with Pt-specific mass activities about twice that of pure Pt nanoparticles.

A new series of ruthenium polypyridyl complexes with a hydroxypyridine ligand were prepared, and their properties were investigated spectroscopically and electrochemically. Particular focus is paid to the effects of protonation–deprotonation and ethylation of the hydroxypyridine ligand, which affects the NMR, electronic spectroscopy, and electrochemistry of the complex. The changes to the UV-vis spectrum were used to determine a pka of 10.5 for the hydroxypyridine nitrogen. In the NMR, protonation of the hydroxypyridine ligand of the complex causes changes in the chemical shifts of the protons on both the hydroxypyridine and bipyridine rings, indicating some degree of electronic communication between these ligands. In addition, it is found that deprotonation of the hydroxypyridine ligand strongly affects the redox potential of the ruthenium metal center, shifting it more negative by 0.4 V. While the electrochemistry of the protonated complex contains irreversible electrochemical events, both deprotonation and subsequent ethylation of the hydroxypyridine ligand result in reversible electrochemistry for all events within the solvent window. For the ethylated complex, we search for a ligand to ligand charge transfer band, corresponding to electron transfer between bipyridine ligands in the mixed valence state. Despite the potential for electronic coupling between ligands through the metal center, we were unable to find any spectroscopic evidence of such electronic coupling.

2-3 nm sized Pt3Co nanoparticles (NPs) with Pt-enriched shells on a carbon support were prepared by a one-step ultrasound polyol process on Pt(acac)(2) (acac = acetylacetonate) and Co(acac)(2). The ultrasound facilitates the conversion of Co(acac)(2) and retards the conversion of Pt(acac)(2) into NPs, which can be explained with the different vapour pressures of the metal precursors. The Pt-enriched shell structure of the NPs by this method, as opposed to the alloy-like elemental distribution of the NPs synthesized in similar conditions but without ultrasound, was evidenced by transmission electron microscopy, magnetism data, extended X-ray absorption fine structure analyses, and chemical replacement tests of Co with Ru3+. Electrochemical oxygen reduction reaction data of these NPs showed improved performance from the commercial Pt/C with the NPs with Pt-enriched shells showing the highest activity. Refereed/Peer-reviewed

We demonstrate that gold nanoparticles can become catalytically active for the electrochemical hydrogen oxidation reaction by a sonication treatment. Experimental data and theoretical calculations indicate that the activity arises from the supercooled molten state of gold nanoparticles which are enriched with coordinatively unsaturated gold atoms.