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 firstname.lastname@example.org
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.
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.
To determine the level of vitamin D and to identify the association between vitamin D and depressive symptoms in apparently healthy Korean male adults.
A retrospective study design. Among 43 513 participants between 1 March and 30 November 2018, after eliminating participants with a history of depression or vitamin D deficiency, 9058 were included. To determine the level of vitamin D, serum 25-hydroxyvitamin D [25(OH)D] was measured. To assess the level of depression, the Korean version of the Center for Epidemiologic Studies Depression Scale (CES-D) was used.
Male adults who underwent routine health check-ups.
The average vitamin D level was 22·31 ± 7·09 ng/ml as 25(OH)D, while the number of subjects in the vitamin D insufficiency group with a finding of <20 ng/ml was 3783 (41·8 %). The mean CES-D score in all subjects was 8·31 ± 5·97 points, and the proportion of the depressive symptoms group with a score of ≥16 was 8·71 %. The OR of patients in the depressive symptoms group also being in the insufficiency group was found to be 1·49 (95 % CI 1·12, 2·00).
A total of 41·8 % of apparently healthy male adults had vitamin D levels <20 ng/ml. We identified an association between vitamin D insufficiency and depressive symptoms in apparently healthy Korean male adults.
The aim of this study was to model the relationships among white matter hyperintensities (WMHs), depressive symptoms, and cognitive function and to examine the mediating effect of depressive symptoms on the relationship between WMHs and cognitive impairment.
We performed structural equation modeling using cross-sectional data from 1158 patients from the Clinical Research for Dementia of South Korea (CREDOS) registry who were diagnosed with mild-to-moderate dementia. Periventricular white matter hyperintensities (PWMHs) and deep white matter hyperintensities (DWMHs) were obtained separately on the protocol of magnetic resonance imaging (MRI). Depression and cognitive function were assessed using the Korean Form of the Geriatric Depression Scale (KGDS) and the Seoul Neuropsychological Screening Battery (SNSB), respectively.
The model that best reflected the relationships among the variables was the model in which DWMHs affected cognitive function directly and indirectly through the depressive symptoms; on the other hand, PWMHs only directly affected cognitive function.
This study presents the mediation model including the developmental pathway from DWMHs to cognitive impairment through depressive symptoms and suggests that the two types of WMHs may affect cognitive impairment through different pathways.
Despite the possibility that cognitive deficits associated with depression may have different patterns depending on the level of neurocognitive impairment, there remains no clear evidence of this. This study aimed to investigate the differential association between depression and cognitive function in patients with mild cognitive impairment (MCI) and Alzheimer’s disease (AD).
A cross-sectional analysis was performed of data from 1,724 patients with MCI and 1,247 patients with AD from the Clinical Research Center for Dementia in Korea. Depression was assessed using the Korean form of the Geriatric Depression Scale, and cognition was measured using the Seoul Neuropsychological Screening Battery, which includes five domains (attention, language and related function, visuospatial function, memory, and frontal/executive function).
Significant differences were found between the two groups (non-depressed vs. depressed) in visuospatial, memory, and executive function domains in the MCI group, as well as in the attention domain in the AD group. The association between depressive symptoms and cognitive function was significantly greater in patients with MCI than in those with AD. These associations were more pronounced in memory and executive function.
Our findings suggest that the association between depression and decreased cognitive function is more pronounced in MCI than AD.
A sediment core (14DH-C01) obtained from the mouth of Gomso Bay, on the west coast of South Korea, was used to obtain high-resolution palynomorph, grain-size, and 14C age data to investigate the Holocene sedimentary environment. The results indicated a transgressive depositional process with four stages controlled by sea-level change, as follows: river-dominated fluvial deposition from the early Holocene to 8.48 cal ka BP; tide-dominated tidal channel fill transgression from 8.48 to 8.08 cal ka BP; tide- to wave-dominated tidal channel fill transgression from 8.08 to 6.98 cal ka BP; and wave-dominated marine transgression from 6.98 cal ka BP to the present. Tidal channel filling was the primary mid-Holocene depositional process, accounting for the high sedimentation rate observed. The different hydrodynamics of the river-dominated, tide-dominated, tide- to wave-dominated, and wave-dominated processes following the changes in sea level may have controlled the transgressive depositional process. This transgressive sedimentary model differs from those of other large river mouth areas (e.g., the Changjiang River) since the mid-Holocene, perhaps resulting from the limited sediment supply in the study area.
While normative data on neuropsychological performance provide baseline metrics for the assessment and diagnosis of mild cognitive impairment and dementia, a lack of comparative normative data in non-Caucasian populations makes it difficult to conduct similar evaluations and studies in individuals from diverse backgrounds. The current paper aims to provide normative data on a range of cognitive measures in a Korean general population sample and investigate various demographic and health variables associated with cognitive performance in this representative population.
The study population was 1,528 stroke and dementia-free individuals who participated in the Korean Genome and Epidemiology study (KoGES) (mean age 60.43 ± 7.30, 52.42% female). All participants underwent a comprehensive neuropsychological test battery that included verbal and visual memory, language, attention, and executive function measures. A health examination and a questionnaire-based interview were also administered.
The majority of cognitive test results were associated with age, education, and gender. In general, higher education and younger age was associated with better cognitive performance. Explained variance increased modestly in models that included measures of general health and depressive symptoms.
Normative data of cognitive performance in a community based Korean population are presented. These norms provide reference values in a non-Caucasian middle to older aged sample.
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.
Personality may predispose family caregivers to experience caregiving differently in similar situations and influence the outcomes of caregiving. A limited body of research has examined the role of some personality traits for health-related quality of life (HRQoL) among family caregivers of persons with dementia (PWD) in relation to burden and depression.
Data from a large clinic-based national study in South Korea, the Caregivers of Alzheimer's Disease Research (CARE), were analyzed (N = 476). Path analysis was performed to explore the association between family caregivers’ personality traits and HRQoL. With depression and burden as mediating factors, direct and indirect associations between five personality traits and HRQoL of family caregivers were examined.
Results demonstrated the mediating role of caregiver burden and depression in linking two personality traits (neuroticism and extraversion) and HRQoL. Neuroticism and extraversion directly and indirectly influenced the mental HRQoL of caregivers. Neuroticism and extraversion only indirectly influenced their physical HRQoL. Neuroticism increased the caregiver's depression, whereas extraversion decreased it. Neuroticism only was mediated by burden to influence depression and mental and physical HRQoL.
Personality traits can influence caregiving outcomes and be viewed as an individual resource of the caregiver. A family caregiver's personality characteristics need to be assessed for tailoring support programs to get the optimal benefits from caregiver interventions.
The Sewol ferry disaster is one of the most tragic events in Korea’s modern history. Among the 476 people on board, which included Danwon High School students (324) and teachers (14), 304 passengers died in the disaster (295 recovered corpses and 9 missing) and 172 survived. Of the rescued survivors, 72 were attending Danwon High School, located in Ansan City, and residing in a residence nearby. Because the students were young, emotionally susceptible adolescents, both the government and the parents requested the students be grouped together at a single hospital capable of appropriate psychiatric care. Korea University Ansan Hospital was the logical choice, as the only third-tier university-grade hospital with the necessary faculty and facilities within the residential area of the families of the students. We report the experiences and the lessons learned from the processes of preparing for and managing the surviving young students as a community-based hospital. (Disaster Med Public Health Preparedness. 2017;11:389–393)
In interpreting radiocarbon dating results, it is important that archaeologists distinguish uncertainties derived from random errors and those from systematic errors, because the two must be dealt with in different ways. One of the problems that archaeologists face in practice, however, is that when receiving dating results from laboratories, they are rarely able to critically assess whether differences between multiple 14C dates of materials are caused by random or systematic errors. In this study, blind tests were carried out to check four possible sources of errors in dating results: repeatability of results generated under identical field and laboratory conditions, differences in results generated from the same sample given to the same laboratory submitted at different times, interlaboratory differences of results generated from the same sample, and differences in the results generated between inner and outer rings of wood. Five charred wood samples, collected from the Namgye settlement and Hongreyonbong fortress, South Korea, were divided into 80 subsamples and submitted to five internationally recognized 14C laboratories on a blind basis twice within a 2-month interval. The results are generally in good statistical accordance and present acceptable errors at an archaeological scale. However, one laboratory showed a statistically significant variance in ages between batches for all samples and sites. Calculation of the Bayesian partial posterior predictive p value and chi-squared tests rejected the null hypothesis that the errors randomly occurred, although the source of the error is not specifically known. Our experiment suggests that it is necessary for users of 14C dating to establish an organized strategy for dating sites before submitting samples to laboratories in order to avoid possible systematic errors.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
It is controversial whether Borna disease virus (BDV) infects humans and causes psychiatric disorders.
The relationship between BDV infection and schizophrenia with deficit syndrome was investigated.
Using the Schedule for the Deficit Syndrome, 62 schizophrenic in-patients were selected from three psychiatric hospitals. RNA was extracted from peripheral blood mononuclear cells and analyzed using nested reverse transcriptase-polymerase chain reaction with primers to detect BDV p24 and p40.
Results and conclusions:
BDV transcripts were not detected in samples from any of the 62 schizophrenic patients. These data do not support an etiologic association between BDV infection and the deficit form of schizophrenia.
We investigated the microstructural evolution of Sn96.4Ag2.8Cu0.8 solder through in situ heating transmission electron microscopy observations. As-soldered bump consisted of seven layers, containing the nanoeutectic lamella structure of AuSn and Au5Sn phases, and the polygonal grains of AuSn2 and AuSn4, on Au-plated Cu bond pads. Here, we found that there are two nanoeutectic lamellar layers with lamella spacing of 40 and 250 nm. By in situ heating above 140°C, the nanoeutectic lamella of AuSn and Au5Sn was decomposed with structural degradation by sphering and coarsening processes of the lamellar interface. At the third layer neighboring to the lamella layer, on the other hand, Au5Sn particles with a zig-zag shape in AuSn matrix became spherical and were finally dissipated in order to minimize the interface energy between two phases. In the other layers except both lamella layers, polycrystal grains of AuSn2 and AuSn4 grew by normal grain growth during in situ heating. The high interface energy of nanoeutectic lamella and polygonal nanograins, which are formed by rapid solidification, acted as a principal driving force on the microstructural change during the in situ heating.
Resistance degradation of zirconium (Zr)-doped barium titanate (BaTiO3) was investigated. A series of Ba(Ti1−yZry)O3 powders and coarse-grained ceramics ranging y from 0 to 0.1 were prepared. The increase of Zr concentration systematically increased the time to as well as electric field to degradation. Such behaviors directly corresponded to those of ionic conduction contribution as evaluated by the Warburg impedance. The magnitude of Warburg impedance decreased with the increase of Zr concentration, which demonstrates that the Zr incorporation inhibits the ionic conduction caused by oxygen vacancies. The prototype multilayer ceramic capacitor (MLCC) samples were also prepared by applying these Ba(Ti1−yZry)O3 base powders and formulated X5R additives of commercial application. In this case, however, such distinct difference in degradation behavior with the variation of Zr concentration did not appear. It is supposed that the influence of additives far outweighs the effect of relative difference in the ionic conduction of Ba(Ti1−yZry)O3 under the MLCC test condition where the applied electric field strength is much higher than those for the coarse-grained bulk ceramics. Resistance degradation of MLCC under such high field might not be explained by only oxygen vacancy-related behavior alone.
Non-steroidal anti-inflammatory drugs cause gastric ulceration through a number of mechanisms including inhibition of PG synthesis, generation of reactive oxygen species (ROS) and induction of apoptosis. Recently, matrix metalloproteinases (MMP) have been suggested to play a crucial role in these mechanisms. The present study investigated the protective effect of anthocyanins isolated from black rice bran (Heugjinjubyeo) against naproxen-induced gastric mucosal injury in rats. The oral administration of anthocyanins (5, 25 or 50 mg/kg body weight) showed significant protection against naproxen (80 mg/kg body weight)-induced gastric ulcer and inhibited lipid peroxidation in the gastric mucosa. In addition, pretreatment with anthocyanins resulted in a significant increase in the activities of radical-scavenging enzymes such as superoxide dismutase, catalase and glutathione peroxidase. Also biochemical and zymographic analyses suggested that the administration of anthocyanins gives a significant protection against naproxen-induced gastric antral ulcer through scavenging ROS and regulation of matrix metalloproteinase-2 (MMP-2) activity. The results of intracellular radical activation show that anthocyanins suppress the generation of intracellular ROS and attenuate the suppression of MMP-2 activity by naproxen. These results suggest that anthocyanins extracted from black rice may offer potential remedy of gastric antral ulceration.
We performed this study to investigate the effect of histone deacetylase inhibition during extended culture of in vitro matured mouse oocytes. In vitro matured mouse (BDF1) oocytes were cultured in vitro for 6, 12, and 24 h, respectively, and then inseminated. During in vitro culture for 6 and 12 h, two doses of trichostatin A (TSA), a histone deacetylase inhibitor, were added (100 nM and 500 nM) to the culture medium and the oocytes were then inseminated. During the 24-h in vitro culture, two doses of TSA were added (100 nM and 500 nM) to the medium and the oocytes were activated with 10 mM SrCl2. After the 6-h culture, the fertilization rate was similar to that of the control group, but the blastocyst formation rate was significantly decreased. After the 12-h culture, both the fertilization and blastocyst formation rates were significantly decreased. After the 24-h culture, total fertilization failure occurred. In the oocytes cultured for 6 and 12 h, the fertilization and blastocyst formation rates did not differ between the TSA-supplemented and control groups. Although extended culture of the mouse oocytes significantly affected their fertilization and embryo development, TSA supplementation did not overcome their decreased developmental potential.
This study aimed to investigate whether aquaporin 3 (Aqp3) mRNAs are expressed in immature oocytes and altered during in vitro maturation process. Five- to 6-week-old female ICR mice were primed by gonadotropin for 24 and 48 h. Immature oocytes obtained 48 h after priming were also matured in vitro for 17 to 18 h. In vivo matured oocytes were obtained after 48 h priming followed by hCG injection. Total RNAs were extracted from 80 to 150 oocytes in each experimental group, and the levels of Aqp3 mRNA were quantified by real-time reverse transcriptase polymerase chain reaction. The experiments were repeated twice using different oocytes. The Aqp3 mRNA was expressed in immature oocytes, as well as in in vitro and in vivo matured oocytes. The expression level was higher in immature oocytes obtained 48 h after priming (17.2 ± 8.6, mean ± SD) than those with no priming (5.7 ± 0.8) or obtained 24 h after priming (2.5 ± 0.8). The expression of Aqp3 mRNA decreased after in vitro maturation (1.2 ± 0.5), which was similar to in vivo matured oocytes (1.0 ± 0.0). Our work demonstrated that Aqp3 mRNA expression increased during the development of immature oocyte but decreased after completion of in vitro maturation. The results indicate that AQP3 is certainly needed for the acquisition of immature oocytes’ full growing potential within antral follicles.
To improve the IPD reliability of NAND flash memory, plasma oxidation was introduced as the post-treatment process of ONO (Oxide/Nitride/Oxide) IPD. The LP-CVD SiO2 modified by plasma oxidation showed the excellent electrical properties. e.g., low leakage current, high breakdown voltage etc. By the analysis of Tof-SIMS and XRR, we could observe the several changes of physical characteristics such as the reduction of impurities (H, N etc.), the increase of oxide density, and the improvement of oxide surface roughness. We found out the appropriate treatment condition to be able to densify oxide layer without the addition of ONO Equivalent Oxide Thickness (EOT). The LP-CVD SiO2 prepared by plasma oxidation was used for the ONO IPD of 50nm NAND flash device and also compared with the conventional LP-CVD SiO2 in the aspect of the IPD reliability.