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Ohiocrinus byeongseoni n. sp. from the Middle Ordovician (Darriwilian) Jigunsan Formation of South Korea in the Sino-Korean (North China) block is the oldest species of Ohiocrinus of the Cincinnaticrinidae and the first record outside Laurentia. O. byeongseoni is characterized by a loosely clockwise-coiled anal sac, isotomous branching throughout arms, long, slender xenomorphic column, and small lichenocrinid-type holdfast. The new species occurs in association with a deep-water siliciclastic environment, unlike the Laurentian species with a shallow-water carbonate environment. The monospecific crinoid assemblage is interpreted as parautochthonous, considering that the crinoids were reworked by relatively weak down-current probably caused by storm but preserved within the environment where they lived. The occurrence of O. byeongseoni presents a considerable spatiotemporal gap and ecologic disparity in evolution of Ohiocrinus and the Cincinnaticrinidae.
There are growing concerns about the impact of the COVID-19 pandemic on the mental health of older adults. We examined the effect of the pandemic on the risk of depression in older adults.
We analyzed data from the prospective cohort study of Korean older adults, which has been followed every 2 years. Among the 2308 participants who completed both the third and the fourth follow-up assessments, 58.4% completed their fourth follow-up before the outbreak of COVID-19 and the rest completed it during the pandemic. We conducted face-to-face diagnostic interviews using Mini International Neuropsychiatric Interview and used Geriatric Depression Scale. We performed generalized estimating equations and logistic regression analyses.
The COVID-19 pandemic was associated with increased depressive symptoms in older adults [b (standard error) = 0.42 (0.20), p = 0.040] and a doubling of the risk for incident depressive disorder even in euthymic older adults without a history of depression (odds ratio = 2.44, 95% confidence interval 1.18–5.02, p = 0.016). Less social activities, which was associated with the risk of depressive disorder before the pandemic, was not associated with the risk of depressive disorder during the pandemic. However, less family gatherings, which was not associated with the risk of depressive disorder before the pandemic, was associated with the doubled risk of depressive disorder during the pandemic.
The COVID-19 pandemic significantly influences the risk of late-life depression in the community. Older adults with a lack of family gatherings may be particularly vulnerable.
We calculated the human resources required for an antimicrobial stewardship program (ASP) in Korean hospitals.
Multicenter retrospective study.
Eight Korean hospitals ranging in size from 295 to 1,337 beds.
The time required for performing ASP activities for all hospitalized patients under antibiotic therapy was estimated and converted into hours per week. The actual time spent on patient reviews of each ASP activity was measured with a small number of cases, then the total time was estimated by applying the determined times to a larger number of cases. Full-time equivalents (FTEs) were measured according to labor laws in Korea (52 hours per week).
In total, 225 cases were reviewed to measure time spent on patient reviews. The median time spent per patient review for ASP activities ranged from 10 to 16 minutes. The total time spent on the review for all hospitalized patients was estimated using the observed number of ASP activities for 1,534 patients who underwent antibiotic therapy on surveillance days. The most commonly observed ASP activity was ‘review of surgical prophylactic antibiotics’ (32.7%), followed by ‘appropriate antibiotics recommendations for patients with suspected infection without a proven site of infection but without causative pathogens’ (28.6%). The personnel requirement was calculated as 1.20 FTEs (interquartile range [IQR], 1.02–1.38) per 100 beds and 2.28 FTEs (IQR, 1.93–2.62) per 100 patients who underwent antibiotic therapy, respectively.
The estimated time required for human resources performing extensive ASP activities on all hospitalized patients undergoing antibiotic therapy in Korean hospitals was ~1.20 FTEs (IQR, 1.02–1.38) per 100 beds.
Yarn-type supercapacitors should have high energy density in small given spaces, and the one attempt among many is to comprise the electrodes asymmetrically. However, the low capacitance of conventional materials causes the widened operating voltage useless. In this study, we have utilized a novel material MXene with carbon nanotubes (CNTs) to make highly loaded MXene/CNT yarn electrodes, which exhibited a remarkable areal capacitance. With MnO2/CNT biscrolled cathode and PVA/LiCl gel electrolyte, the plied asymmetric yarn supercapacitor had energy density of 100 µWh/cm2. The yarn supercapacitor could operate under mechanical deformations without performance degradation.
It has not been well established whether dietary folate intake reduces the risk of diabetes development. We aimed to clarify the prospective association between dietary folate intake and type 2 diabetes (T2D) risk among 7333 Korean adults aged 40 years or older who were included in the Multi-Rural Communities Cohort. Dietary folate intake was estimated from all 106 food items listed on a FFQ, not including folate intake from supplements. Two different measurements of dietary folate intake were used: the baseline consumption and the average consumption from baseline until just before the end of follow-up. The association between folate intake and T2D risk was determined through a modified Poisson regression model with a robust error estimator controlling for potential confounders. For 29 745 person years, 319 cases of diabetes were ascertained. In multivariable analyses, dietary folate intake was inversely associated with risk of T2D for women, not for men. For women, the incidence rate ratio of diabetes in the third tertile compared with the first tertile was 0·57 (95 % CI 0·38–0·87, Pfor trend=0·0085) in the baseline consumption model and 0·64 (95 % CI 0·43–0·95, Pfor trend=0·0244) in the average consumption model. These inverse associations was found in both normal fasting blood glucose group and impaired fasting glucose group among women. Among non-users of multinutrients and vitamin supplements, the significant inverse association remained. Thus, higher dietary intake of folate is prospectively associated with lower risk of diabetes for women.
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.
Diet may play an important role in breast cancer recurrence or survival, and therefore assessment of long-term diet among breast cancer survivors is important in breast cancer survivorship research. Given that the diet of breast cancer survivors may differ from that of the general population, the use of a FFQ specific to this group may be needed. The objective of this study was to develop a FFQ for breast cancer survivors, the most commonly used tool to measure long-term dietary patterns in nutritional epidemiological studies. We collected information on the foods and amounts of foods consumed using 3-d dietary records from a total of 192 women who had been diagnosed with stage I–III breast cancers and had undergone breast cancer surgery at least 6 months before the baseline study. A total of 1254 foods and dishes consumed were re-grouped by the similarity of the main ingredients and/or serving units, and several dishes commonly consumed among the Korean population were added. After we performed contribution analyses and variability analyses to detect between-person variation for selected nutrients, we listed a total of 123 foods and dishes for the FFQ specific to breast cancer survivors. Our breast cancer survivor-specific FFQ can be used to estimate long-term dietary intake and to examine its association with breast cancer prognosis in epidemiological studies of breast cancer in Korea.
This study reports the earliest known reef-building anthaspidellid sponge, Rankenella zhangxianensis n. sp., from the Cambrian Series 3 (late Stage 5–early Guzhangian) deposit of the Zhangxia Formation, Shandong Province, China. Rankenella zhangxianensis mostly occurs within Epiphyton-Rankenella-Cambroctoconus reefs, with minor occurrence from inter-reef grainstone. The species has anthaspidellid-type regular ladderlike spicule networks consisting of dendroclones and trabs, and is characterized by trabs parallel/subparallel to the gastral surface that diverge and meet the dermal surface, which is typical of the genus. Compared to R. mors and R. hamdii, reported from the late Cambrian Series 2–late Cambrian Series 3 of Australia and the late Cambrian Series 3–early Furongian of Iran, respectively, R. zhangxianensis is characterized by a relatively thicker wall, high angle (~90°) between dermal surfaces and intersecting trabs, and minor occurrence of differentiated canals. On the other hand, R. zhangxianensis mainly shows obconical shape, which is far less diverse than the other two species showing conicocylindrical, digitate, explanate, or bowl shapes. These Cambrian Series 3 reefs from China are the ancestors of the Furongian anthaspidellid-microbial reefs and the Early Ordovician anthaspidellid-microbial reefs that flourished worldwide. They represent the resurgence of reef-building metazoans after the extinction of archaeocyaths at the end of Cambrian Series 2.
Lichenaria may be a representative of the most primitive stock of tabulate corals. The degree of paleobiologic complexity discovered in L. globularis and L. grandis is therefore surprising. Six types of corallite increase are recognized. All are lateral, which is the predominant mode in tabulates. Most types, however, are unique or are comparable to those in few other Ordovician taxa. Only Type 1 (L. globularis), yielding a single offset with a simple basal mural pore, is typical of tabulates. In Type 2 (L. globularis), one parent produces two offsets simultaneously, whereas in Type 3 (L. globularis), two offsets arise from separate parents at nearly the same time and join via a connective mural pore. Types 4 (L. globularis, L. grandis), 5 (L. grandis), and 6 (L. globularis, L. grandis), respectively, involve one, two, and two to four corallites in addition to the parent, which join via a connective mural pore at the site of offsetting.
Several features of L. globularis and L. grandis point to unexpectedly high levels of colony integration. Continuously fused common walls lacking back-to-back epithecae suggest soft tissue continuity among polyps above the corallum. Connective mural pores indicate temporary fusion of polyps. Coordinated behavior of polyps is suggested by the development of conjoined offsets from two parents during Type 3 increase, and by fusion during Types 4 to 6 increase. Attempts at certain types of increase sometimes failed to yield offsets, suggesting expendability of incipient buds, perhaps reflecting subjugation of individuals for the good of the colony.
In light of this study, genera that have previously been included in Lichenariidae and Lichenariida require reassessment and their phylogenetic relationships should be reconsidered. Unfortunately, this is hindered because fundamental characters such as corallite increase and wall structure remain inadequately known in most early tabulates.
This study evaluated the impacts of earlier traumatic events on the mental health of older adults, in terms of mental disorders and mental well-being, according to sociodemographic variables, trauma-related characteristics, and personality traits in a nationally representative sample of older Koreans.
A total of 1,621 subjects aged 60 to 74 years from a Korean national epidemiological survey of mental disorders responded face-to-face interviews. The Korean Composite International Diagnostic Interview was used to investigate lifetime trauma exposure (LTE) and psychiatric diagnoses. The EuroQol health classification system and life satisfaction scale were used to assess quality of life (QoL), and the Big Five Inventory-10 (BFI-10) to measure personality traits.
Five-hundred and seventy-seven subjects (35.6%) reported a history of LTE (mean age at trauma, 30.8 years old). Current mental disorders were more prevalent in elderly people with LTE, while better current QoL was more frequent in those without LTE. Among older people with LTE, lower extraversion and higher neuroticism increased the risk of current mood or anxiety disorders, whereas higher extraversion increased the probability of experiencing mental well-being after adjusting for sociodemographic and trauma-related variables.
Personality traits, especially extraversion, and neuroticism, may be useful for predicting the mental health outcomes of LTE in older adults. Further longitudinal studies investigating the relationship between traumatic events and mental health outcomes are needed.
We aimed to evaluate the reproducibility and validity of the newly developed FFQ for the Korean National Health and Nutrition Examination Survey (KNHANES) and to estimate the measure’s calibration factors.
The 109-item FFQ was administered twice, approximately 9 months apart. We also collected four seasonal 3 d dietary records (DR) as a reference method. Correlation coefficients and joint classification were computed to compare intakes of energy, thirteen nutrients and eleven food groups between the two FFQ to evaluate reproducibility. For validity, de-attenuated and energy-adjusted correlation, joint classification and Bland–Altman statistics were calculated for energy and nutrients between the first FFQ and the DR. To calibrate the FFQ, we performed a linear regression analysis in which the DR were the dependent variables and FFQ, age and sex were the independent variables.
Seoul metropolitan area, Republic of Korea.
A total of 126 adults aged 20–65 years.
The average correlation coefficients measuring reproducibility were 0·54 for nutrients and 0·57 for food groups. The mean correlation coefficient measuring validity was 0·40 for all nutrients between the first FFQ and the DR. On average, 75 % of the participants were classified into the same or adjacent quartiles, while 5 % of the participants were grossly misclassified. The mean energy and nutrient intakes estimated by the calibrated FFQ were similar to the means estimated by the DR.
The newly developed FFQ for assessing dietary intake in the KNHANES has acceptable reproducibility and modest validity compared with a 12 d DR collected over a 9-month period.
This study aimed to investigate the influences of age, education, and gender on the two total scores (TS-I and TS-II) of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological assessment battery (CERAD-NP) and to provide normative information based on an analysis for a large number of elderly persons with a wide range of educational levels.
In the study, 1,987 community-dwelling healthy volunteers (620 males and 1,367 females; 50–90 years of age; and zero to 25 years of education) were included. People with serious neurological, medical, and psychiatric disorders (including dementia) were excluded. All participants underwent the CERAD-NP assessment. TS-I was generated by summing raw scores from the CERAD-NP subtests, excluding Mini-Mental State Examination and Constructional Praxis (CP) recall subtests. TS-II was calculated by adding CP recall score to TS-I.
Both TS-I and TS-II were significantly influenced by demographic variables. Education accounted for the greatest proportion of score variance. Interaction effect between age and gender was found. Based on the results obtained, normative data of the CERAD-NP total scores were stratified by age (six overlapping tables), education (four strata), and gender.
The normative information will be very useful for better interpretation of the CERAD-NP total scores in various clinical and research settings and for comparing individuals’ performance of the battery across countries.
Mutation breeding techniques have been used to induce new genetic variations and improve agronomic traits in soybean. In Korea, the Korea Atomic Energy Research Institute (KAERI) has unique radiation facilities to induce plant mutations and has been conducting soybean mutation breeding programmes since the mid-1960s. Until now, the KAERI has developed five soybean mutant cultivars exhibiting early maturity, high yield and seed-coat colour change. In this paper, we review these five mutant cultivars in terms of how to successfully induce unique agronomic characteristics through mutation breeding programmes. A number of induced mutants exhibiting null lipoxygenase enzymes, altered protein patterns or Kunitz trypsin inhibitor activity could serve as genetic resources for the genetic analysis of target genes, and one mutant population has been developed for a reverse genetic study.
Social support programs for dementia caregivers were widely used in order to reduce care burden. We investigated which types of social supports can reduce psychological and non-psychological burdens of dementia caregivers, and explored the mechanism of those social supports.
We evaluated 731 community-dwelling dementia patients and their caregivers from the National Survey of Dementia Care in South Korea. We investigated the five types of social supports (emotional support, informational support, tangible support, positive social interaction, affectionate support) using the Medical Outcomes Study Social Support Survey in each caregiver. The mechanisms of specific types of social support on psychological/non-psychological burden were examined using path analysis.
Positive social interaction and affectionate support reduced psychological burden via direct and indirect paths. Tangible support reduced the non-psychological burden via direct and indirect paths. Informational support and emotional support were not helpful for reducing psychological or non-psychological burden. A maximum of 20% of psychological burden could be relieved by positive social interaction and 10.3% of that could be reduced by affectionate support. Tangible support was associated with a 15.1% maximal improvement in non-psychological burden.
In order to reduce caregiver burden in dementia effectively, psychosocial interventions should be tailored to target type of caregiver burden.
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.
Sources of variation in nutrient intake have been examined for Western diets, but little is known about the sources of variation and their differences by age and sex among Koreans. We examined sources of variation in nutrient intake and calculated the number of days needed to estimate usual intake using 12 d of dietary records (DR). To this end, four 3 d DR including two weekdays and one weekend day were collected throughout four seasons of 1 year from 178 male and 236 female adults aged 20–65 years residing in Seoul, Korea. The sources of variation were estimated using the random-effects model, and the variation ratio (within-individual:between-individual) was calculated to determine a desirable number of days. Variations attributable to the day of the week, recording sequence and seasonality were generally small, although the degree of variation differed by sex and age (20–45 years and 46–65 years). The correlation coefficient between the true intake and the observed intake (r) increased with additional DR days, reaching 0·7 at 3–4 d and 0·8 at 6–7 d. However, the degree of increase became attenuated with additional days: r increased by 13·0–26·9 % from 2 to 4 d, by 6·5–16·4 % from 4 to 7 d and by 4·0–11·6 % from 7 to 12 d for energy and fifteen nutrients. In conclusion, the present study suggests that the day of the week, recording sequence and seasonality minimally contribute to the variation in nutrient intake. To measure Korean usual dietary intake using open-ended dietary instruments, 3–4 d may be needed to achieve modest precision (r>0·7) and 6–7 d for high precision (r>0·8).
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.
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.