To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Nanocrystalline (NC) and ultrafine-grained (UFG) CoCrCuFeNi high-entropy alloy (HEA) with grain size ranging between 59 and 386 nm was produced via powder metallurgy and heat treatment. The as-sintered HEA exhibited two face-centered cubic (FCC) phases (CoCrFeNi-rich and Cu-rich phases) and a small grain size (59 nm), whereas the alloy after heat treatment at 1000 °C exhibited a CoCuFeNi-rich phase with FCC structure and relatively larger grain size (386 nm). Moreover, the yield strength decreased from 1930 to 883 MPa, and plastic strain to failure increased by 8–32%. In terms of microstructural evolution, grain boundary strengthening coupled with lattice distortion was the dominant strengthening mechanism for NC HEAs. Furthermore, the coefficient for boundary strengthening was higher in the HEAs than in the corresponding pure elemental metals with FCC structure, possibly because of significant lattice distortion. The UFG HEAs exhibited high strength and good ductility because of the activation of dislocation.
This study investigates the relationship between insomnia and cognitive dysfunctions including, subjective memory impairment (SMI), mild cognitive impairment (MCI), and dementia, by considering depression in a community sample of elderly individuals.
Data for 1,740 elderly individuals aged 65 years and over were obtained from a nationwide dementia epidemiological study conducted in South Korea. Cognitive functional status was assessed by the Mini-Mental State Examination and the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet Clinical Assessment Battery. Insomnia was defined as the presence of at least one of the four sleep complaints (difficulty in initiating sleep, difficulty in maintaining sleep, early morning awakening, and non-restorative sleep), accompanied by moderate to severe daytime consequences. Depression was evaluated using the Geriatric Depression Scale.
The prevalence of insomnia in the patients with SMI, MCI, and dementia was found to be 23.2%, 19.6%, and 31.0%, respectively. The patients with SMI, MCI, and dementia were significantly more likely to have insomnia and the four sleep complaints than the normal comparison patients. After adjusting for sociodemographic factors, the significant relationships between cognitive dysfunctional status and insomnia remained. However, after adjusting for sociodemographic factors and depression, no significant relationships with any of the sleep complaints or insomnia remained.
Insomnia is a very common complaint in the elderly with SMI, MCI, and dementia. Depression might play an important factor in the relationship between insomnia and cognitive dysfunctional status in the elderly.
In many countries, illiteracy rates among aged people are quite high. However, only few studies have specifically investigated the impact of illiteracy on depression.
Data for 1,890 elderly individuals (aged ≥65 years) were obtained from a nationwide dementia epidemiological study conducted in South Korea. Based on their reading ability, the participants were divided into three groups: totally illiterate, partially illiterate, and literate. The Korean version of the Geriatric Depression Scale – Short Form (SGDS-K) was used to detect depression (cut-off score = 8). Multivariate logistic regression analyses were used to assess the association between illiteracy and depression. To explore clinical features of depression in illiterate people, we performed logistic regression to calculate odds ratios of positive responses (or negative responses to reverse-coded items) for each SGDS-K item using literate individuals as the reference group.
Totally illiterate participants had 2.41 times the odds and partially illiterate individuals had 1.59 times the odds of being depressed compared with literate participants after controlling for other variables. Compared with literate individuals, illiterate elderly persons were at increased odds for responding negatively to the majority of SGDS-K items, including “having memory problems,” “others are better off than me,” and “feeling worthless” even after controlling for various demographic and clinical factors.
Illiteracy in elderly individuals was associated with a higher rate and increased severity of depression. Illiteracy negatively affected depression symptomatology, especially factors associated with self-esteem. Therefore, clinicians should carefully monitor for the presence of depression in illiterate elderly adults.
Background: Insomnia is a common psychiatric complaint among elderly individuals. This study investigates the prevalence and sociodemographic correlates of insomnia by considering a community sample of elderly individuals in South Korea.
Methods: A face-to-face household survey was conducted in five regions of South Korea from June 2008 to August 2008. Among a total of 3,074 individuals aged 65 years and over, 2,002 participants were interviewed. The presence of insomnia was defined as having at least one of four sleep complaints that included difficulty in initiating sleep (DIS), difficulty in maintaining sleep (DMS), early morning awakening (EMA), and non-restorative sleep (NRS) more than three times per week in the last month. The Restless Legs Syndrome (RLS) Questionnaire, a short form of the Geriatric Depression scale (GDS), and a medical review of systems were implemented.
Results: Insomnia was found in 29.2% of the participants. DIS, DMS, EMA, and NRS accounted for 19.4%, 21.7%, 19.6%, and 8.0% of the participants respectively. Insomnia accompanied by daytime consequences accounted for 17.1% of the participants. The participants who were females, had no education, lived alone, showed symptoms of RLS or depression, and had a lifetime history of physical illness were significantly more likely to report insomnia. The prevalence of DIS, DMS, EMA, or insomnia increased slightly with age, whereas that of NRS decreased slightly. The lifetime history of head trauma, hyperlipidemia, heart disease, anemia, or depression was significantly related to insomnia.
Conclusion: Sleep problems are common among elderly individuals and are closely related to their lifetime history of physical illness.
We investigated the relationship of oestrogen receptor (ER) status to the severity of depressive symptoms and quality of life (QOL) impairment in breast cancer patients.
Seventy-seven breast cancer patients with comorbid depression were evaluated with the Hamilton Depression Rating Scale (HAMD), the Clinical Global Impression-Severity of Illness (CGI-S) for depression, and the Functional Assessment of Cancer Therapy-Breast (FACT-B). ER status was determined using immunohistochemical analysis.
The ER-positive group (n = 31) showed significantly higher scores compared with the ER-negative group (n = 46) on HAMD total (p = 0.04) and somatic anxiety factor (p = 0.004) scores as well as CGI-S score (p = 0.03). As for QOL measured with the FACT-B, a significantly higher score was found on the Functional Well-Being (FWB) subscale in the ER-positive group (p = 0.001). The relationships were further analysed using generalised linear models (GLM), after controlling for the influence of the current anti-oestrogen treatment. The analysis revealed that ER status was still significantly related to the FWB subscale score of the FACT-B (p = 0.04). However, the HAMD and CGI-S scores were no longer significantly related to ER status after the influence of anti-oestrogen treatment was controlled for.
These results suggest that ER status, which is a well-known biological prognostic factor in breast cancer, may be related to the severity of certain aspects of depressive symptoms or QOL impairment, implying a role of the ER in affective and behavioural regulation. However, anti-oestrogen treatments significantly influence these relationships.
Background: The influences of demographics, culture, language, and environmental changes on Mini-Mental State Examination (MMSE) scores are considerable.
Methods: Using a sample of 7452 healthy, community-dwelling elderly Koreans, aged 55 to 94 years, who participated in the four ongoing geriatric cohorts in Korea, we investigated demographic influences on MMSE scores and derived normative data for this population. Geropsychiatrists strictly excluded subjects with cognitive disorders according to the protocol of the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet (CERAD-K) Clinical Assessment Battery (CERAD-K-C).
Results: Education (standardized β = 0.463), age (standardized β = −0.303), and gender (standardized β = −0.057) had significant effects on MMSE scores (p < 0.001). The score of MMSE increase 0.379 point per 1-year education, decrease 0.188 per 1-year older, and decrease 0.491 in women compared to men. Education explained 30.4% of the scores’ total variance, which was much larger than the variances explained by age (8.4%) or gender (0.3%). Accordingly, we present normative data for the MMSE stratified by education (0, 1–3, 4–6, 7–9, 10–12, and ≥ 13 years), age (60–69, 70–79, and 80–89 years), and gender.
Conclusions: We provide contemporary education-, age-, and gender-stratified norms for the MMSE, derived from a large, community-dwelling elderly Korean population sample, which could be useful in evaluating individual MMSE scores.
In this study, Adhesion force and Nanotribological Characteristics of fluorocarbon (FC) films on Al deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD) were evaluated. The contact angle of FC thin films on Al was measured to be around 110°. The surface energy was calculated to be 15 dynes/cm from the measurements of contact angles of polar and nonpolar solutions on surfaces. The contact angle hysteresis, which is an indicator for the surface heterogeneity, was lower than 30°. The friction force of FC films coated surfaces was three times lower than bare Al. The adhesion force of bare Al was measured to be around 9.6nN. The presence of FC films on Al reduced it to below 4nN. Fourier transform infra-red (FTIR) spectra showed the presence of fluorocarbon groups such as –CFn- and =CF=CF2.
Email your librarian or administrator to recommend adding this to your organisation's collection.