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Background: Although small- and medium-sized hospitals comprise most healthcare providers in South Korea, data on antibiotic usage is limited in these facilities. We evaluated the pattern of antibiotic usage and its appropriateness in hospitals with <400 beds in South Korea. Methods: A multicenter retrospective study was conducted in 10 hospitals (6 long-term care hospitals, 3 acute-care hospitals, and 1 orthopedic hospital), with <400 beds in South Korea. We analyzed patterns of antibiotic prescription and their appropriateness in the participating hospitals. Data on the monthly antibiotic prescriptions and patient days for hospitalized patients were collected using electronic databases from each hospital. To avoid the effect of the COVID-19 pandemic, data were collected from January to December 2019. For the evaluation of the appropriateness of the prescription, 25 patients under antibiotic therapy were randomly selected at each hospital over 2 separate periods. Due to the heterogeneity of their characteristics, the orthopedics hospital was excluded from the analysis. The collected data were reviewed, and the appropriateness of antibiotic prescriptions was evaluated by 5 specialists in infectious diseases (adult and pediatric). Data from 2 hospitals were assigned to each specialist. The appropriateness of antibiotic prescriptions was evaluated from 3 aspects: route of administration, dose, and class. If the 3 aspects were ‘optimal,’ the prescription was considered ‘optimal.’ If only the route was ‘optimal,’ and the dose and/or class was ‘suboptimal,’ but not ‘inappropriate,’ it was considered ‘suboptimal.’ If even 1 aspect was ‘inappropriate,’ it was classified as ‘inappropriate.’ Results: The most commonly prescribed antibiotics in long-term care hospitals was fluoroquinolone, followed by β-lactam/β-lactamase inhibitor (antipseudomonal). In acute-care hospitals, these were third-generation cephalosporin, followed by first-generation cephalosporin and second-generation cephalosporin. The major antibiotics that were prescribed in the orthopedics hospital was first-generation cephalosporin. Only 2.3% of the antibiotics were administered inappropriately. In comparison, 15.3% of patients were prescribed an inappropriate dose. The proportion of inappropriate antibiotic prescriptions was 30.6% of the total antibiotic prescriptions. Conclusions: The antibiotic usage patterns vary between small- and medium-sized hospitals in South Korea. The proportion of inappropriate prescriptions exceeded 30% of the total antibiotic prescriptions.
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.
Complement factor H (CFH) plays a key role in regulating the cascade of the alternative pathway of the complement system. Dysregulation of CFH may be involved in the pathophysiology of various inflammation-mediated diseases including neuropsychiatric illnesses. This study aimed to investigate this relationship by examining determining CFH levels in elderly individuals with and without depression.
A total of 152 elderly individuals (major depressive disorder (MDD) group, n = 76; comparison sample, n = 76) were selected from the Ansan Geriatric study. The plasma level of CFH was measured. MDD was diagnosed with the Mini-International Neuropsychiatric Interview as per DSM-IV criteria. The severity of depression was evaluated with the geriatric depression scale (GDS). Mean CFH levels were compared using the Mann–Whitney U test. After adjusting for possible confounding factors including age, sex, marital status, education, alcohol use, hemoglobin levels, and the Korean version of the Mini-Mental State Examination (MMSE-KC), a multiple regression analysis was conducted. The GDS score and plasma level of CFH were analyzed using Spearman's correlation.
Plasma CFH level was significantly higher in individuals with MDD than in the comparison sample (289.51 ± 21.16 vs. 339.67 ± 66.23, p < 0.001). In a regression model adjusted for possible confounders, CFH was significantly associated with geriatric depression (p < 0.001). CFH levels were not significantly related to GDS scores in the depressed group.
This study revealed an association between high plasma levels of CFH and geriatric depression, thereby suggesting the alternative pathway of the complement system contributing to the development of geriatric depression.
The Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) is a reliable, validated informant-based instrument in screening for cognitive dysfunction. However, previous studies have evaluated only the ability to discriminate dichotomously, such as dementia from cognitively normal (CN) individuals or mild cognitive impairment (MCI) from CN. This study investigated the ability of the IQCODE to classify not only dichotomous but also multiple stages of cognitive dysfunction.
We examined 228 consecutive participants (76 CN, 76 with MCI, and 76 with dementia). Receiver operating characteristic (ROC) curves determined dichotomous classification parameters. Multi-category ROC surfaces were evaluated to classify three stages of cognitive dysfunction.
Dichotomous classification using the ROC curve analyses showed that the area under the ROC curve was 0.91 for dementia from participants without dementia and 0.71 for MCI from CN. Simultaneous multi-category classification analyses showed that the volume under the ROC surface was 0.61 and the derived optimal cut-off points were 3.15 and 3.73 for CN, MCI, and dementia. The Youden index for the IQCODE was estimated as 0.51 and the derived optimal cut-off points were 3.33 and 3.70. The overall classification accuracy by the VUS was 58.3% and that by the Youden index 61.8%.
IQCODE is useful to classify the dichotomous and multi-category stages of cognitive dysfunction.
Korea Microlensing Telescope Network (KMTNet) which consists of three identical 1.6 m wide-field telescopes with 18k × 18k CCDs, is the first optical survey system of its kind. The combination of fast optics and the mosaic CCD delivers seeing limited images over a 4 square degrees field of view. The main science goal of KMTNet is the discovery and characterization of exoplanets, yet it also offers various other science applications including DEep Ecliptic Patrol of SOUTHern sky (DEEP-South). The aim of DEEP-South is to discover and characterize asteroids and comets, including Near Earth Objects (NEOs). We started test runs last February after commissioning, and will return to normal operations in October 2015. A summary of early results from the test runs will be presented.
Korea Astronomy and Space Science Institute (KASI) successfully completed the development of Korea Microlensing Telescope Network (KMTNet, Park et al. 2012) in mid-2015, following which it conducted test runs for several months. ‘DEep Ecliptic Patrol of the Southern sky’ (DEEP-South, Moon et al. 2015), which will be used for asteroid and comet studies, will not only characterize targeted asteroids, carrying out blind surveys toward the sweet spots, but will also mine the data of such bodies using the KMTNet archive. We report preliminary lightcurves of four Potentially Hazardous Asteroids (PHAs) from test runs at KMTNet-CTIO in the February - May 2015 period.
We started ‘DEep Ecliptic Patrol of the Southern sky’ (DEEP-South, DS) (Moon et al. 2015) in late 2012, and conducted test runs with the first Korea Microlensing Telescope Network (KMTNet) (Park et al. 2012), a 1.6 m telescope with 18k x 18k CCD stationed at CTIO in early 2015. While the primary objective of DEEP-South is the physical characterization of small Solar System bodies, it is also expected to discover a large number of such bodies, many of them previously unknown. An automated observation scheduling, data reduction and analysis software subsystem called ‘DEEP-South Scheduling and Data reduction System’ (DS SDS) is thus being designed and implemented to enable observation planning, data reduction and analysis with minimal human intervention.
We investigated the characteristics of Alzheimer's disease (AD) biomarkers for mild cognitive impairment (MCI) reversion to cognitively normal (CN).
Of a total of 1,233 participants from the ADNI database, 42 participants with MCI reversion to CN (MCIr), 778 with MCI, and 413 CN were obtained. We evaluated demographics, clinical outcomes, medication use, MCI type, and AD biomarkers, including genetic, cerebrospinal fluid, imaging, and neuropsychological data.
This study showed that the differences between MCIr and CN were only age, Mini-Mental State Examination, and Clinical Dementia Rating – Sum of Boxes, but the differences between MCIr and MCI were not only clinical outcomes but also AD biomarkers, including genetic, cerebrospinal fluid, imaging, and neuropsychological data. Overall, MCIr may be similar to CN and not MCI in clinical characteristics.
With assessment of MCI reversion to CN, the possibility of false-positive errors should be considered. With the assistance of AD biomarkers, MCI can be evaluated more accurately than the conventional criteria.
A 44-year-old man developed sudden non-fluent aphasia and right hemiplegia due to left striatocapsular infarction (Figure). Neurologic examination revealed gaze deviation to the right with eyes closed, but not with eyes open (Video). There was no spontaneous or gaze-evoked nystagmus, even after elimination of visual fixation. Leftward pursuit was impaired in a craniotopic frame of reference, and horizontal saccades were hypometric in both directions. Head impulse test was normal in the horizontal plane and there were no visual field defects. The contralesional gaze deviation with eye closure persisted for ten days.
Octamer-binding transcription factor 4 (Oct4) is a critical molecule for the self-renewal and pluripotency of embryonic stem cells. Recent reports have shown that Oct4 also controls cell-cycle progression and enhances the proliferation of various types of cells. As the high proliferation of donor fibroblasts is critical to the production of transgenic pigs, using the somatic cell nuclear transfer technique, we analysed the effect of Oct4 overexpression on the proliferation of porcine fibroblasts and embryos. Porcine endogenous Oct4 cDNA was cloned, sequenced and inserted into an expression vector. The vector was transfected into porcine fibroblasts, and a stable Oct4-overexpressed cell line was established by antibiotic selection. Oct4 expression was validated by the immunostaining of Oct4. Cell morphology was changed to sharp, and both proliferation and migration abilities were enhanced in Oct4-overexpressed cells. Real-time RT-PCR results showed that p16, Bcl2 and Myc were upregulated in Oct4-overexpressed cells. Somatic cell nuclear transfer was performed using Oct4-overexpressed cells, and the development of Oct4 embryos was compared with that of wild-type cloned embryos. The cleavage and blastocyst formation rates were improved in the Oct4 embryos. Interestingly, blastocyst formation of the Oct4 embryos was observed as early as day 5 in culture, while blastocysts were observed from day 6 in wild-type cloned embryos. In conclusion, the overexpression of Oct4 enhanced the proliferation of both porcine fibroblasts and embryos.
Genetic variation in wild soybean (Glycine soja Sieb. and Zucc.) is a valuable resource for crop improvement efforts. Soybean is believed to have originated from China, Korea, and Japan, but little is known about the diversity or evolution of Korean wild soybean. Therefore, in this study, we evaluated the genetic diversity and population structure of 733 G. soja accessions collected in Korea using 21 simple sequence repeat (SSR) markers. The SSR loci produced 539 alleles (25.7 per locus) with a mean genetic diversity of 0.882 in these accessions. Rare alleles, those with a frequency of less than 5%, represented 75% of the total number. This collection was divided into two populations based on the principal coordinate analysis. Accessions from population 1 were distributed throughout the country, whereas most of the accessions from population 2 were distributed on the western side of the Taebaek and Sobaek mountains. The Korean G. soja collection evaluated in this study should provide useful background information for allele mining approach and breeding programmes to introgress alleles into the cultivated soybean (G. max (L). Merr.) from wild soybean.
Although there are rapidly growing concerns about the high rates of cognitive dysfunction in Korea, the knowledge of risk factors for Alzheimer’s disease (AD) among the general public in Korea remains to be elucidated.
A total of 2767 randomly selected subjects from the Ansan Geriatric Study were questioned on their knowledge of putative risk factors for AD. Their answers were compared with their sociodemographic data and other variables.
The most common stated risk factor was being older (59.6%), followed by head trauma (33.6%) and cerebrovascular disease (30.4%). However, a substandard education, which is a known risk factor, was considered significant by only 9.5% of the subjects. Predictors for a worse knowledge of the risk factors for AD were being older, a lower level of education, lower economic status and the attitude that dementia is not curable.
This study revealed that misunderstanding about AD is more prevalent in older subjects and those with a lower level of education, and so public health education on the basic concepts of AD should be targeted at this population.
This paper summarizes the recent standardization activities in the field of robotics by ISO (International Organization for Standardization), IEC (International Electrotechnical Commission), OMG (Object Management Group), and other organizations. While the standards in industrial robots have been mainly developed by ISO, the standards on the emerging service robots are initiated by many organizations. One of the goals of this paper is to coordinate the efforts among these groups so that more effective standardization activity can be executed. Standardization in the emerging service robots will eventually promote the proliferation of service robot markets in the near future.
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, we investigated the effect of two oxygen concentrations (5 and 20%) during in vitro maturation (IVM) and during in vitro culture (IVC) on porcine embryo development and analysed differences in gene expression between cumulus–oocyte complexes matured under 5 or 20% oxygen and the resulting blastocysts cultured under 5% or 20% oxygen following parthenogenetic activation. There was no significant difference in oocyte maturation rate. However, the numbers of resulting blastocysts were significantly increased in the 5% IVC group compared with the 20% IVC group. Moreover, the M20C5 treatment group (23.01%) supported greater blastocyst development compared with the M5C5 (14.32%), M5C20 (10.30%), and M20C20 (17.88%) groups. However, total cell numbers were not significantly different among groups. According to mRNA abundance data of multiple genes, each treatment altered the expression of genes in different patterns. GLUT1, G6PD and LDHA were up-regulated in cumulus cells that had been matured in low oxygen, suggesting a higher glucose uptake and an increase in anaerobic glycolysis, whereas cyclin B1 (CCNB) and MnSOD (Mn-superoxide dismutase) were upregulated in cumulus cells that had been matured in high oxygen, which suggests a higher activity of mitosis-promoting factor and antioxidant response. In spite of these differential effects on cumulus cells, oocytes could mature normally regardless of different oxygen concentrations. Therefore, it can be concluded that high oxygen concentration during in vitro maturation and low oxygen during in vitro culture may alter the expression of multiple genes related to oocyte competence and significantly improves embryo development (p < 0.05) but not blastocyst quality.
Background: Extrapyramidal signs (EPSs), which are important characteristics of Parkinson's disease (PD), occur frequently in Alzheimer's disease (AD). Although AD and PD share common clinical features such as EPSs, these diseases vary with respect to vascular risk factors. The presence of vascular risk factors increases the risk of AD; however, these factors have been known to be inversely associated with PD. We aimed to assess the effect of vascular risk factors and white matter lesions (WMLs) on EPSs in AD.
Methods: We recruited 1,187 AD patients and 333 controls with neither cognitive impairment nor EPSs. All participants underwent detailed clinical evaluations which included assessments of vascular risk factors, cognitive function, and EPSs, as well as WMLs on brain MRIs. EPS subtypes were classified into tremor-dominant, postural instability gait difficulty, or indeterminate; WMLs subtypes were classified into periventricular WML (pvWML) or deep WML (dWML).
Results: EPSs were present in 17.9% of subjects with AD and were significantly associated with vascular risk factors such as age, male gender, diabetes mellitus, and WMLs. Additionally, a multivariate logistic regression analysis showed that EPSs in AD were associated with pvWML (odds ratio (OR), 1.61–2.52), not with dWML. With respect to EPS subtypes, the majority (78.4%) of EPSs in AD were postural instability gait difficulty, which was also associated with WMLs (OR 1.84–2.41), pvWML (OR 2.09–3.14), and dWML (OR 1.83–3.42).
Conclusions: EPSs in AD are associated with selected vascular risk factors as well as WMLs.
Compared to plastic, from the view point of ultra low temperature poly-Si (ULTPS) processes for realizing flexible active matrix organic light emitting diode (AM-OLED) display, SSF offers high thermal resistance and chemical stability, and lithography stability. As SSF is stiffer than plastic film, SSF is expected to reduce stress which originates from difference in coefficient of thermal expansion. However, SSF substrate itself also bears surface roughness problem, which necessitates an appropriate planarization step. Also to fully integrate both the drive circuits and the pixel thin-film transistor(TFT)s in a monolithic complementary metal-oxide-semiconductor (CMOS) technology high mobility is required, calling for poly-Si usage.
We will deal with the planarization process, and then address various processing issues. Especially, we will demonstrate our successful SLS of Si on SSF substrates. Finally we show the device performances. All fabrication temperatures were kept below 200 oC to meet a ULTPS process.
Due to the rolling process for manufacturing foils, the SSF surface is rough. We have measured average roughness of 500 nm, respectively. With benzocyclobutene (BCB), we have successfully planarized the surface with average roughness was less than 0.5 nm.
Our TFT's active layer was obtained by laser crystallizing amorphous Si (a-Si) films. To obtain a high quality gate dielectric film, we formed a SiO2 film using an O2 plasma treatment on the surface of the poly-Si film and then deposited Al2O3 film by plasma enhanced atomic layer deposition. Then gate metal was deposited and patterned. Source and drain regions were p+ doped by ion implantation to form a self-aligned gate structure. We have used SiNx film as interlayer dielectrics.
Briefly we discuss a practical approach for realizing SLS on a SiO2 buffer. The Si-on-SiO2 layer stacking is energetically unstable. Should have not controlled the heat during laser crystallization, liquid Si would recede to expose the SiO2 layer. Dewetting is suppressed by adjusting the buffer density, and densifying the a-Si film. To implement the SLS, we have optimally conjugated the densities of the buffer film and the a-Si film to produce Si grains with sizes of ~6 ¥ìm on a BCB planarized SSF.
Our p-channel TFT transfer performance exhibits a field effect mobility (¥ì) of 95 cm2/Vs, a threshold voltage (Vt) of -3 V and a sub-threshold swing(S-S) of 0.5 V/dec.. The off-current level is ~ 10 pA at drain voltage (Vd) of -1V and the Ion/Ioff is 106 . Especially our stable Vt consents to the electrical stability for driving displays. This feature might be attributed to the improved interface between the active layer and the gate dielectrics by plasma oxidation.
Due to a rapid shrinkage in memory devices, backned of the line process experiences great difficulties, especially Al metallization. Furthermore, there is a continuous demands in low line resistance in order to promote device performances. In this article, Al damascene process is proposed as compared to Al patterning process, which suffers from inherent pattering issue at a fine pitch under 70nm. The most difficulties in the development of Al damascene process were to form a stable and void free Al in fine trench and to obtain scratch and corrosions free Al surface. In this study, 50nm beyond fill was successfully achieved by “bottom up growth” of CVD Al. For the process, CVD Al by using Methylpyrroridine Alane (MPA) precursor was deposited on a stacked film of CVD TiN and PVD TiN as a wetting layer, which was followed by PVD Al and reflow, then the Al surface was polished with colloidal silica based slurry.
In addition, electrical property of Al scheme and W scheme was compared with damascene pattern, along with which we demonstrated that around 36% decrease in parasitic capacitance is achievable by decrease of metal line height from 3500A to 1000A on simulation test implying that device performance could be enhanced.
BaIn2S4, BaIn2S4:Ho3+, BaIn2S4:Er3+, BaIn2S4:Tm3+, BaIn2Se4, BaIn2Se4:Ho3+, BaIn2Se4:Er3+, and BaIn2Se4:Tm3+ single crystals were grown by the chemical transport reaction method. The optical energy gap of the single crystals was found to be 3.057, 2.987, 2.967, 2.907, 2.625, 2.545, 2.515, and 2.415 eV, respectively, at 11 K. The temperature dependence of the optical energy gap was well fitted by the Varshni equation. Broad emission peaks were observed in the photoluminescence spectra of the single crystals. They were assigned to donor–acceptor pair recombination. Sharp emission peaks were observed in the doped single crystals. They were attributed to be due to radiation recombination between the Stark levels of the Ho3+, Er3+, and Tm3+ ions sited in C1 symmetry.
The thermal activation energies for conduction of Nb-doped SrTiO3 grains and grain boundaries have been investigated by impedance spectroscopy. First, to observe the effect of electrode/SrTiO3 bulk interface, the varied impedances of SrTiO3 single crystal were measured with temperatures. The activation energy of an electrode/bulk interface was determined to be 1.3 eV, whereas that of bulk was 0.8 eV. When the impedances of Nb-doped SrTiO3 ceramics were measured, it was suggested that the more precise impedance values of a single grain and a single grain to grain junction be obtained using a microelectrode method. The activation energies for a grain, a grain boundary, and an electrode/bulk interface were determined to be about 0.8, 1.3, and 1.5 eV, respectively. From these measured results, it was suggested that the activation energy, 0.8 eV, measured in grain was originated from oxygen vacancies and the activation energy, 1.3 eV, in grain boundary was from strontium vacancies.