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The geological sequestration of carbon dioxide (CO2) is an alternative strategy for mitigating global warming. The CO2 storage capacity is often characterized by the capillary pressure curve, which in turn depends on the pressure and temperature of the injected CO2 and the internal structure of the reservoir rocks. The key structural feature that influences the storage capacity in porous rocks is their inherent anisotropy. An experimental study was performed to investigate the optimal conditions for CO2 injection into an anisotropic sandstone. The capillary pressure curve and the residual CO2 saturation were determined by injecting three CO2 phases into the directionally cored sandstone specimens with different flow rates. The CO2 saturation in sandstone increased with increasing flow rate, resulting in asymptotic values. The storage capacity of CO2 was the highest in the order of liquid CO2 (LCO2), supercritical CO2 (scCO2), and gaseous CO2 (gCO2). It was also the highest when the direction of CO2 injection was normal in relation to the embedded sandstone layers. The in situ cored sandstone from the Janggi Basin in Korea was further tested to examine the effect of its pore size on the capillary pressure of CO2. [ABSTRACT FROM AUTHOR]

Abstract: Aim: To evaluate the nutritional status of older adults with dementia who were living in long‐term care settings. Methods: As a secondary analysis, this study used the data from the Nationwide Survey on Dementia Care in Korea that was conducted between December 1, 2010, and August 31, 2011, which surveyed 3472 older adults with dementia, aged ≥60 years (mean age: 81.24 years), who were residing in 248 randomly selected long‐term care settings in South Korea. Twenty‐three different variables that related to the participants’ demographics, diseases, and functional and nutritional characteristics were selected. The nutritional status was assessed by using the Mini Nutritional Assessment (MNA). Descriptive statistics, an ANOVA, and a chi‐squared test were used to analyze the data. Results: The mean MNA score of the participants was 17.90. The malnutrition rate was 38.4% (n = 1333), with 54.7% (n = 1900) of the participants at risk for malnutrition. The largest population with malnutrition resided in long‐term care hospitals (47.9%), followed by nursing homes (34.1%), and group homes (25.9%). Being older and female, while exhibiting higher cognitive impairment, more neuropsychiatric symptoms, higher functional dependency, and a higher number of disabilities, were associated with poor nutritional status. Conclusion: The nutritional status of older adults with dementia who were living in long‐term care settings in South Korea was poor and associated with multiple factors. Paying special attention to recognizing, assessing, preventing, and treating malnutrition in this population is necessary. [ABSTRACT FROM AUTHOR]

The purpose of this study was to identify family caregivers’ experiences in managing the behavioral and psychological symptoms of dementia (BPSD) with particular focus on their interpersonal interactions with patient with dementia. Data were collected through focus-group interviews with 15 family caregivers from three local dementia-support centers located in Seoul. Data were analyzed using content analysis. Three main themes were identified through data analysis: triggers of BPSD, family caregiver’s actions in response to BPSD and patient’s reactions, and the effect of BPSD on family caregivers. Findings demonstrated that BPSD depended on the complex interplay of family caregivers and patients, including their interaction style. This information could help nurses when counseling and educating family caregivers to improve or modify their attitudes and approaches to behavioral symptoms of patients. [ABSTRACT FROM AUTHOR]

Purpose: To determine the predictors of agreement with writing advance directives (ADs) among older Korean adults. Design: This was a secondary analysis of a study that compared the differences in knowledge, experience, and preference about ADs between community and facility-dwelling older adults. Data were collected through self-reported questionnaires. In this study, after 25 cases were excluded from the original sample (N = 181) for incomplete data, a sample of 156 was analyzed using multiple logistic regression analysis. Results: Older adults’ experiences with having thought about life-sustaining treatments, odds ratio (OR) = 4.02, 95% confidence interval (CI) [1.56, 10.38], agreements with legalization of ADs, OR = 4.68, 95% CI [1.69, 12.96], and wishes to obtain information about medical status, OR = 3.78, 95% CI [1.66, 8.64], were identified as the predictors of agreement with writing ADs. Implications for Practice: Discussion channels and educational programs about ADs should be developed for older Korean adults. [ABSTRACT FROM AUTHOR]

Families' caring competence plays a key role in caring for the elderly with dementia. In particular, the management of the behavioural and psychological symptoms of dementia is different from the management of other symptoms of dementia. However, there is no tool for evaluating family caregiver competence for managing the behavioural and psychological symptoms of dementia. This study aimed to develop a competence scale in managing the behavioural and psychological symptoms of dementia for family caregivers and to evaluate its psychometric properties. An instrument development and cross-sectional validation study was conducted. Twenty-one local dementia centres in Seoul, Korea. A total of 460 community-dwelling family caregivers of people living with dementia (mean age = 69.82 ± 11.08, female = 78.7%, spouse = 65.7%) participated in the study. This study was conducted in two steps: (1) instrument development and (2) psychometric tests (N = 460). After item generation and the evaluation of content validity and face validity, a total of 39 preliminary items were tested. For the psychometric tests, item analysis using the corrected item-to-total correlations and construct validity with exploratory and confirmatory factor analysis were performed. Using measurement tools of the Behaviour Management Skill, a Visual Analogue Scale, and a general question of the scale developed in this study, the concurrent validity was examined by calculating Pearson's correlation coefficient. Reliability was evaluated with Cronbach's α, test reliability with the standard error of measurement, and test-retest reliability with the intraclass correlation coefficient. The exploratory and confirmatory factor analyses yielded a six-factor solution with 28 items. The six factors were 'person-centred attitude', 'introspection for improvement', 'symptom occurrence analysis', 'application of various strategies', 'awareness of symptoms' and 'caring for one's own mind and body'. The concurrent validity was established. The reliability was demonstrated to be acceptable (Cronbach's α = 0.922, ICC = 0.781). The competence scale in managing the behavioural and psychological symptoms of dementia for family caregivers was found to be a valid and reliable instrument. The scale is potentially useful for promoting better dementia care in both research and clinical practice settings by enabling the identification of needs to be improved for family caregivers in coping with dementia symptoms. [ABSTRACT FROM AUTHOR]

Aims and objectives To explore the degree of eating ability in people with dementia and identify what factors affect their eating ability. Background Appropriate food consumption is important to human life. Although eating difficulties are common among people with dementia, little is known about what factors might influence their eating ability. Design Descriptive, cross-sectional study. Methods A total of 149 people with dementia residing in nursing facilities in Seoul or the Gyeonggi area of Korea were evaluated using the Korean Mini-Mental State Examination, Korean Activities of Daily Living Scale and Eating Behaviour Scale. Data were analysed using descriptive statistics, one-way analysis of variance, Pearson correlation coefficient and multiple regression analysis. Results The participants showed a moderate level of dependency with respect to eating ability and were most dependent on the use of utensils. There were significant differences in eating ability according to general characteristics such as duration of residence, duration of illness, degree of visual impairment, eating place, and diet type. The eating ability of the participants was significantly correlated with cognitive function and physical function. Cognitive function, physical function, duration of illness, eating place (living room or dining room), and diet type (soft or liquid) significantly predicted eating ability in people with dementia. Conclusions The findings of this study suggest that it is necessary to thoroughly assess the eating ability of people with dementia and to develop appropriate training programs to maintain or improve their remaining eating ability. The creation of a pleasurable physical and social environment for eating might also be helpful. Relevance to clinical practice These findings would be able to serve a useful basis in the development of materials for nursing intervention programs for people with dementia during mealtimes by improving the techniques and care qualities of nursing caregivers. [ABSTRACT FROM AUTHOR]

Structures constructed before seismic design standards in Korea were enacted are being seismically and structurally strengthened for structural performance. The jacket method has been used to enhance the shear load-carrying capacity and ductility of reinforced concrete columns. This study investigated the effect of glass fiber-reinforced polyurea (GFRPU) on the enhancement of shear strength and ductility. It was shown that the GFRPU spraying technique played an important role in enhancing the column because of the material characteristics of the GFRPU, that is, high-tensile strength and elongation. The reinforcement effect of GFRPU on the shear-span ratio and axial-force ratio of six reinforced concrete (RC) column specimens was evaluated. The experimental results demonstrated that the lateral-reinforcement effect and energy-dissipation capacity were improved. The H-series and S-series specimens reinforced by the GFRPU with an axial-load ratio of 0.1 exhibited higher shear strength, of about 30% and 18%, than the specimens without reinforcement. The shear-load-carrying capacity of the S-series specimen with the axial-load-force ratio of 0.2 increased by 4%. The design method representing the lateral-resistance ability of the GFRPU was represented by an empirical formula reflecting the experimental results. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the incidence rate and risk factors of stroke in patients treated with bilateral TKA compared with patients with unilateral TKA. Methods: In this retrospective nationwide cohort study, we compared patients undergoing unilateral TKA or bilateral TKA using data from the Korean National Health Insurance claims database between January 1, 2009 and August 31, 2017 and included patients older than 40 years of age who underwent primary TKA by the index date as documented primary diagnosis and first additional diagnosis without a history of stroke during the preceding 1 year. We used matched Cox regression models to compare the incidence rate and risk factors of newly acquired stroke among patients treated with unilateral TKA or bilateral TKA after propensity score (PS) matching. Results: In the present study, 163,719 patients who received unilateral TKA were matched to 163,719 patients with bilateral TKA based on PS. The risk of stroke during the study period was lower in patients treated with bilateral TKA than in patients with unilateral TKA (adjusted hazard ratio [HR] 0.79). Patients who received bilateral TKA were at decreased risk of stroke when the following variables were present: advanced age (70–79 years, HR 0.76), female sex (HR 0.75), rural area (HR 0.77), small- or medium-sized hospital (HR 0.75), health insurance (HR 0.77), history of hypertension drug use (HR 0.75), congestive heart failure (HR 0.70), connective tissue disease (HR 0.71), diabetes (HR 0.77), and diabetes with complication (HR 0.76). Conclusion: The risk of stroke was lower in patients treated with bilateral TKA than in patients with unilateral TKA. Patients treated with bilateral TKA were at decreased risk of stroke when the following variables were present: age (70–79 years), female sex, health insurance, history of hypertension drug use, and comorbidities, such as congestive heart failure, connective tissue disease, and diabetes. [ABSTRACT FROM AUTHOR]

Protaetia brevitarsis seulensis is an animal‐based medicine used traditionally in China, Japan, and Korea to treat hepatic disorders; it has been shown to possess various pharmacological effects such as antibacterial and antioxidant activities. In this study, we investigated the effects of P. brevitarsis on a testosterone‐induced benign prostatic hyperplasia (BPH) rat model. To establish the BPH model, the animals were administered a subcutaneous injection of testosterone daily for 28 days. P. brevitarsis was administered by oral gavage at doses of 12.5, 25, and 50 mg/kg for 28 days, along with testosterone injection. P. brevitarsis treatment markedly decreased the absolute and relative prostate weight of BPH animals. The levels of dihydrotestosterone was reduced in P. brevitarsis‐treated animals compared to those in the BPH animals. Histological analysis of the prostate showed that P. brevitarsis treatment effectively suppressed the testosterone‐induced hyperplasia of prostatic epithelial cells, which was accompanied by reductions in the PCNA and Ki‐67 expressions in prostatic tissues. These results indicate that P. brevitarsis effectively suppresses testosterone‐induced development of BPH, and thus, is a potential therapeutic agent for BPH. [ABSTRACT FROM AUTHOR]

Chromosome number changes and karyotype evolution play an important role in plant genome diversification and eventually in speciation. The genus Ajuga L. (Lamiaceae) has approximately 50 species distributed in temperate to subtropical regions. Four of these species are currently recognized in Korea (A. decumbens Thunb., A. multiflora Bunge, A. nipponensis Makino and A. spectabilis Nakai). Understanding the karyotype evolution in Ajuga has been hampered by the small size of their chromosomes and symmetrical karyotypes. Here we used classic Feulgen staining to establish chromosome numbers and construct karyotypes of the four species of Ajuga recognized in Korea and flow cytometry was used to study their variation in genome. The chromosome number of all investigated plants was 2n = 32. Still, the 2C DNA content ranged from 2.18 pg (A. decumbens) to 4.53 pg (A. multiflora). While the chromosome numbers were the same for all investigated species, the genome size variation could potentially be used as a taxonomic marker. [ABSTRACT FROM AUTHOR]

• This paper presents the stress test method developed for Korean nuclear power plants focusing assessment method of plant response capability to the loss of safety functions due to extended loss of AC power (ELAP) and loss of ultimate heat sink (LUHS). • This paper also shows assessment results of plant response capability in the events of ELAP and LUHS of OPR1000 that is a standardized PWR by Korea based on the ABB-CE System 80. • Multi-barrier accident coping strategy (MACST) guidelines have been developed to accomplish specific tasks in support of emergency operating procedures (EOP) when the extended loss power AC power and/or loss of ultimate heat sink is in progress as a consequence of beyond design basis natural events. • Safety provisions to secure critical safety functions are presented with cliff edge time evaluation at each step of plant response to extended loss of AC power and loss of ultimate heat sink. This paper presents a stress test method developed for Korean nuclear power plant and assessment results of plant response capability of OPR1000 in an effort to enhance the safety against extreme natural events exceeding the design basis of the plant. Multi-barrier accident coping strategy (MACST) guidelines have been developed to accomplish specific tasks in support of Emergency Operating Procedures (EOP) when the Extended Loss of AC Power (ELAP) and/or Loss of Ultimate Heat Sink (LUHS) is in progress as a consequence of beyond design basis natural events. Provisions to secure critical safety functions are discussed with cliff edge time evaluation at each step of plant response to ELAP and LUHS. It is concluded that the plant can maintain the safe shutdown state through the natural circulation cooldown by steam generator and the electric power and can obtain additional capability and redundancy with off-site equipment to provide coping capability for an indefinite period. [ABSTRACT FROM AUTHOR]