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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.
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.
Cerebral white matter hyperintensities (WMH) are prevalent incident findings on brain MRI scans among elderly people and have been consistently implicated in cognitive dysfunction. However, differential roles of WMH by region in cognitive function are still unclear. The aim of this study was to ascertain the differential role of regional WMH in predicting progression from mild cognitive impairment (MCI) to different subtypes of dementia.
Participants were recruited from the Clinical Research Center for Dementia of South Korea (CREDOS) study. A total of 622 participants with MCI diagnoses at baseline and follow-up evaluations were included for the analysis. Initial MRI scans were rated for WMH on a visual rating scale developed for the CREDOS. Differential effects of regional WMH in predicting incident dementia were evaluated using the Cox proportional hazards model.
Of the 622 participants with MCI at baseline, 139 patients (22.3%) converted to all-cause dementia over a median of 14.3 (range 6.0–36.5) months. Severe periventricular WMH (PWMH) predicted incident all-cause dementia (Hazard ratio (HR) 2.22; 95% confidence interval (CI) 1.43–3.43) and Alzheimer's disease (AD) (HR 1.86; 95% CI 1.12–3.07). Subcortical vascular dementia (SVD) was predicted by both PWMH (HR 16.14; 95% CI 1.97–132.06) and DWMH (HR 8.77; 95% CI 1.77–43.49) in more severe form (≥ 10 mm).
WMH differentially predict dementia by region and severity. Our findings suggest that PWMH may play an independent role in the pathogenesis of dementia, especially in AD.
This paper reports the successive occurrence of Ptychagnostus sinicus Lu, 1957 and Ptychagnostus atavus (Tullberg, 1880) from the lower part of the Machari Formation, Yeongwol Group, Korea. Morphometric approaches of using the landmark and principal component analyses make it possible to differentiate P. sinicus from P. atavus with clarity: pygidia of P. sinicus have a relatively narrow M1, a transverse F2, and a weakly developed M2 tubercle, whereas those of P. atavus are characterized by a broadly arching M1, a chevron-shaped F2, and a prominent M2 tubercle. Recognition of P. atavus, for the first time in Korea, allows the determination of the base of the Drumian Stage in Korea and aids correlation with other parts of the world.
Δ14C values of leaves of deciduous trees provide a means to map the regional-scale fossil fuel ratio in the atmosphere. We collected a batch of ginkgo (Ginkgo biloba Linnaeus, a deciduous tree) leaf samples from across Korea in the month of July in both 2010 and 2011 to obtain the regional distribution of Δ14C. The Δ14C values of the samples were measured using accelerator mass spectrometry (AMS) at the Korea Institute of Geoscience and Mineral Resources (KIGAM). The average of the Δ14C values from clean air sites in Korea in 2011 measured slightly lower than the average of Δ14C values in 2010. Distribution maps of Δ14C of 2011 and 2010 in Korea were made based on a series of Δ14C values of ginkgo leaf samples from Korea using the Geostatistical and Spatial analyst tools in ESRI's ArcMap software. The distribution maps of Δ14C showed that Δ14C values in the western part of Korea are lower than those in the eastern part of Korea. This is because the western part of Korea is densely populated and contains many industrial complexes, and also because westerly winds from China, containing CO2 from fossil fuel use, blow into Korea. We compared the distribution maps of 2010 and 2011 and tried to find traces of the Fukushima power plant accident in Japan.
A total of 245 patients with confirmed 2009 H1N1 influenza were admitted to the intensive-care units of 28 hospitals (South Korea). Their mean age was 55·3 years with 68·6% aged >50 years, and 54·7% male. Nine were obese and three were pregnant. One or more comorbidities were present in 83·7%, and nosocomial acquisition occurred in 14·3%. In total, 107 (43·7%) patients received corticosteroids and 66·1% required mechanical ventilation. Eighty (32·7%) patients died within 30 days after onset of symptoms and 99 (40·4%) within 90 days. Multivariate logistic regression analysis showed that the clinician's decision to prescribe corticosteroids, older age, Sequential Organ Failure Assessment score and nosocomial bacterial pneumonia were independent risk factors for 90-day mortality. In contrast with Western countries, critical illness in Korea in relation to 2009 H1N1 was most common in older patients with chronic comorbidities; nosocomial acquisition occurred occasionally but disease in obese or pregnant patients was uncommon.
We report an extremely rare case of coexisting, ipsilateral nonrecurrent inferior laryngeal nerve and recurrent inferior laryngeal nerve.
We present a case report and a review of the world literature concerning ipsilateral nonrecurrent inferior laryngeal nerve and recurrent inferior laryngeal nerve.
The presence of a coexisting, ipsilateral nonrecurrent inferior laryngeal nerve and recurrent inferior laryngeal nerve is a very rare embryological aberration which is associated with a right subclavian artery originating from the aortic arch. We report a case of coexisting, ipsilateral nonrecurrent and recurrent inferior laryngeal nerves associated with this vascular anomaly.
The surgeon must be aware of the possibility of coexisting, ipsilateral nonrecurrent inferior laryngeal nerve and recurrent inferior laryngeal nerve, and thus must trace the nerve in its entirety. Occasionally, what appears to be a nonrecurrent inferior laryngeal nerve will actually be a communicating branch between the recurrent inferior laryngeal nerve and the oesophageal or sympathetic ganglia. If such a neurological variant is present, the consequences of careless dissection could include not only vocal fold paralysis but also dysphagia (if the pharyngeal and oesophageal branches of nonrecurrent or recurrent inferior laryngeal nerve are injured).
A high temperature combustion method was used to analyze the 14C and 3H activities in graphite and the dose assessment was carried out to determine the clearance in the conservative way. By this method, the 3H and 14C were simultaneously trapped in the nitric acid and carbosorb, respectively. Accordingly, the sample preparation time for the measurement was reduced to the half. The combustion temperature was more than 800 degrees in centigrade for obtaining total tritium and 14C in the sample. The combustion ratio was about 99% on the graphite sample with the weight of 0.1 g. Minimum detectable activity was 0.05 Bq/g for the 14C and 0.15 Bq/g for the 3H at the same background counting time. The recoveries from the combustion furnace were around 100% and 90% in 14C and 3H, respectively. The radioactivity were 2,530 ~ 3,160 Bq/g in 14C and 1,700 ~2,040 Bq/g in 3H at this experiment. The experimental uncertainty was less than 6% in both radionuclides where the furnace recovery was dominant factor. An individual effective dose from beta and gamma radionuclides was estimated by consideration of the scenario of inhalation, ingestion and external exposure. 60Co, the radioactivity of which was measured by using HPGe detector, had a predominant effect in estimating the effective dose. The estimation showed that the graphite wastes from the dismantled research reactor should be disposed of as a low level radioactive waste rather than clearance.
Ferroelectric characteristics of poly(vinylidiene fluoride/trifluoroethylene) (P(VDF/TrFE) (72/28 mol%)) copolymer ultrathin films used as an insulator in varying memory device architectures such as metal-ferroelectric polymer-metal (MFM), MF-insulator-semiconductor (MFIS), MIS and organic field-effect transistor (OFET) were studied using different electrical measurements. A maximum data writing speed of 1.69 MHz was calculated from the switching time measured using MFM architecture. Capacitance-voltage measured using MFIS was found to be more suitable for distinguishing the ‘0’ and ‘1’ state compared to MFM device structure. In OFET, the decreasing channel length increased the measured drain current (Id) values as well as its memory window enabling easier identification of the ‘0’ and ‘1’ state comparable to MFIS case. The data obtained from this study will be useful in the fabrication of non-volatile random access memory (NVRAM) devices with faster data R/W/E speed and memory retention capacity.
We present the TANOS (Si-Oxide-SiN-Al2O3-TaN) cell with 40 Å-thick tunnel oxide erased by Fowler-Nordheim (FN) tunneling of hole. Thanks to introducing high-k dielectrics, alumina (Al2O3) as a blocking oxide, the erase threshold voltage can be maintained to less than - 3.0 V, meaning hole-trapping in SiN. We extracted the nitride trap densities of electron and hole for the TANOS cell. It is demonstrated that the TANOS structure is very available to investigate the trap density with shallower energy. The energy level of hole trap (1.28 eV) is found to be deeper than that of electron (0.8 eV). As the cycling stress is performed, persistent hole-trapping is observed unlike endurance characteristics of conventional floating-gate cell. The hole trapping during the cycling stress can be attributed to two possibilities. The injected holes are trapped in neutral trap of tunnel oxide and residue of holes which is not somewhat compensated by injected electrons may be accumulated in SiN. It is demonstrated the erase operation of the TANOS cell is governed by Fowler-Nordheim tunneling of hole due to the field concentration across the tunnel oxide.
The composition of yeast communities in the rumen of cattle was investigated using comparative DNA sequence analysis of yeast 26S rDNA genes. 26S rDNA libraries were constructed from rumen fluid (FF), rumen solid (FS) and rumen epithelium (FE). A total of 97 clones, containing a partial 26S rDNA sequence of 0·6 kb length, were sequenced and subjected to an on-line similarity search.
The 41 FF clones could be divided into five classes. The largest class was affiliated with Pezizomycotina class (85·4% of clones), and the remaining classes were related with the Urediniomycotina (2·4%), Hymenomycetes (4·9%), Ustilaginomycetes (4·9%) and Saccharomycotina (2·4%) classes. The 26 FE clones could be divided into three classes and the Saccharomycetes class (92·4% of clones) was the largest group. The remaining classes were related with either Pezizomycotina (3·8%) or Ustilaginomycetes (3·8%). The 30 FS clones were all affiliated with Saccharomycotina. Saccharomycotina were predominant in rumen epithelium and rumen solid while Pezizomycotina were predominant in rumen fluid. Yeast belonging to the Saccharomycotina class was predominant in the rumen as a whole (57%). One clone (FF34) had less than 90% similarity to any sequence in the database and was thus apparently unrelated to any previously described yeast.
Acid-resistant specimens of trilobites were recovered from the dissolved residues of lime mudstone collected from the lower part of the Machari Formation, Yongwol Group, Taebaeksan Basin, Korea. One of the samples yields a trilobite assemblage comprising Lejopyge armata (Linnarsson, 1869), Lisogoragnostus coreanicus n. sp., agnostid genus and species indeterminate, ammagnostid genus and species indeterminate, clavagnostid genus and species indeterminate, Cyclolorenzella sp., and Eoshengia? sp. The stratigraphic interval yielding the trilobite assemblage is herein designated as the Lejopyge armata Zone, which is correlated well with the upper Middle Cambrian biozones established elsewhere. This provides the first biostratigraphic reference point for the upper Middle Cambrian sequence of the Yongwol Group and fills partially the biostratigraphic gap between the Tonkinella (middle Middle Cambrian) and the Glyptagnostus stolidotus (uppermost Middle Cambrian) zones in the Machari Formation.
Our system is the electrochemical approaches include the detection of hybridization from nonlabeling nucleic acids to protein-bound nucleic acids using soluble mediators with K4Fe(CN)6 solutions. In order to generate bio-functional surfaces, the streptavidin(SAv)-biotin system is used. A 50 % change of redox peak current after hybridization measured with 50 μM concentration of target DNA. We suggest that this result comes from the efficient electron transport through the SAv-biotin interaction. Our electrochemical detection system showed good reproducibility on a chip with non-labeling DNA hybridization detection.
Thin film electrodes of the perovskite oxide (Ba,Sr)RuO3 (BSR) were deposited on 4 inch ptype Si wafers by metal organic chemical vapor deposition (MOCVD) for the practical (Ba,Sr)TiO3 (BST) capacitor application using a new single cocktail source. The source materials used for the MOCVD BSR process were Ba(METHD)2, Sr(METHD)2 and Ru(METHD)3 and these were dissolved in n-butyl acetate. The source-feeding rate was precisely controlled by liquid mass flow controllers (LMFC). As-deposited BSR films possessed a (110)-oriented structure, with good uniformity and adherence on bare Si wafer. The phase formation was strongly affected by the oxygen flow rate and the input source rate. As the oxygen flow rate increased, the Ru/(Ba+Sr) composition ratio in the film decreased, while the Ba/(Ba+Sr) ratio was almost independent of the oxygen flow rate. The dielectric constants of BST capacitors fabricated using these electrodes was greater than 500.
A series of ZnO thin films with various deposition temperatures were prepared on (100) GaAs substrates by radio-frequency magnetron sputtering using ZnO target. The ZnO films were studied by field emission scanning electron microscope(FESEM), x-ray diffraction(XRD), photoluminescence(PL), cathodoluminescence(CL), and Hall measurements. The structural, optical, and electrical properties of the films were discussed as a function of the deposition temperature. With increasing temperature, the compressive stress in the films was released and their crystalline and optical properties were improved. From the depth profile of As measured by secondary ion mass spectrometry(SIMS), As doping was confirmed, and, in order to activate As dopant atoms, post-annealing treatment was performed. After annealing treatment, electrical and optical properties of the films were changed.
Optical and structural properties of InGaN/GaN quantum wells having growth interruption were investigated using high-resolution x-ray diffraction, photoluminescence and transmission microscopy. InxGa1−xN/GaN (x>0.25) six pair quantum wells used in this study were grown on c- plane sapphire by metalorganic chemical vapor deposition. The growth interruption was carried out by closing the group-III metal organic sources before and after growth of InGaN quantum well layers. With increasing the interruption time, the quantum dot-like region and well thickness decreases due to indium re-evaporation or thermal etching effect. As a result, PL peak position is blue-shifted and intensity is reduced. The size and number of V-defect did not vary with interruption time. The interruption time is not directly related with formation of the defect. The V-defect in quantum wells originates at threading dislocations and inversion domain boundaries due to higher misfit strain.
A novel method to control the recrystallization depth of amorphous silicon (a-Si) film during the excimer laser annealing (ELA) is proposed in order to preserve a-Si that is useful for fabrication of poly-Si TFT with a-Si offset in the channel. A XeCl excimer laser beam is irradiated on a triple film structure of a-Si thin native silicon oxide (~20Å)/thick a-Si layer. Only the upper a-Si film is recrystallized by the laser beam irradiation, whereas the lower thick a-Si film remains amorphous because the thin native silicon oxide layer stops the grain growth of the poly-crystalline silicon (poly-Si). So that the thin oxide film sharply divides the upper poly-Si from the lower a-Si.