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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.
The YSTAR program is a general sky survey looking for variability. The main equipments are three 0.5-m telescopes. These telescopes have fast F/2 optics covering nearly 3.5 square degree field onto a 2K CCD. They also have very fast slew capability, which exceeds 10 degrees per second. These two factors make them most suitable for rapid target acquisition and wide-field surveys of various kinds. Our primary objective is to identify and monitor variable stars down to 18th R-magnitude, and our observing mode allows the same data set to be also useful in identifying asteroids. Our first telescope has just begun regular automated operation, and the second telescope will be installed in South Africa within this year to provide coverage of the southern sky.
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.
The mitochondrial genome is maternally inherited in animals, despite the fact that paternal mitochondria enter oocytes during fertilization. Autophagy and ubiquitin-mediated degradation are responsible for the elimination of paternal mitochondria in Caenorhabditis elegans; however, the involvement of these two processes in the degradation of paternal mitochondria in mammals is not well understood. We investigated the localization patterns of light chain 3 (LC3) and ubiquitin in mouse and porcine embryos during preimplantation development. We found that LC3 and ubiquitin localized to the spermatozoon midpiece at 3 h post-fertilization, and that both proteins were colocalized with paternal mitochondria and removed upon fertilization during the 4-cell stage in mouse and the zygote stage in porcine embryos. Sporadic paternal mitochondria were present beyond the morula stage in the mouse, and paternal mitochondria were restricted to one blastomere of 4-cell embryos. An autophagy inhibitor, 3-methyladenine (3-MA), did not affect the distribution of paternal mitochondria compared with the positive control, while an autophagy inducer, rapamycin, accelerated the removal of paternal mitochondria compared with the control. After the intracytoplasmic injection of intact spermatozoon into mouse oocytes, LC3 and ubiquitin localized to the spermatozoon midpiece, but remnants of undegraded paternal mitochondria were retained until the blastocyst stage. Our results show that paternal mitochondria colocalize with autophagy receptors and ubiquitin and are removed after in vitro fertilization, but some remnants of sperm mitochondrial sheath may persist up to morula stage after intracytoplasmic spermatozoon injection (ICSI).
This study examined changes in health-related quality of life (HRQoL) and quality of care (QoC) as perceived by terminally ill cancer patients and a stratified set of HRQoL or QoC factors that are most likely to influence survival at the end of life (EoL).
We administered questionnaires to 619 consecutive patients immediately after they were diagnosed with terminal cancer by physicians at 11 university hospitals and at the National Cancer Center in Korea. Subjects were followed up over 161.2 person-years until their deaths. We measured HRQoL using the core 30-item European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, and QoC using the Quality Care Questionnaire–End of Life (QCQ–EoL). We evaluated changes in HRQoL and QoC issues during the first three months after enrollment, performing sensitivity analysis by using data generated via four methods (complete case analysis, available case analysis, the last observation carried forward, and multiple imputation).
Emotional and cognitive functioning decreased significantly over time, while dyspnea, constipation, and pain increased significantly. Dignity-conserving care, care by healthcare professionals, family relationships, and QCQ–EoL total score decreased significantly. Global QoL, appetite loss, and Eastern Cooperative Oncology Group Performance Status (ECOG–PS) scores were significantly associated with survival.
Significance of results:
Future standardization of palliative care should be focused on assessment of these deteriorated types of quality. Accurate estimates of the length of life remaining for terminally ill cancer patients by such EoL-enhancing factors as global QoL, appetite loss, and ECOG–PS are needed to help patients experience a dignified and comfortable death.
The modified TiO2 nanoparticles were incorporated into the Bulk heterojunction system of P3HT:PCBM to improve the performance of P3HT:PCBM bulk heterojunction organic solar cells. The organically-modified TiO2 nanoparticle compounds were synthesized in aqueous media at room temperature. These TiO2 compounds in various solution concentrations were deposited on the top of the P3HT:PCBM active layer by spin coating. The performance of organic solar cells was carefully investigated in the respect of the scattering and the localized surface plasmon resonance (LSPR) that couple strongly to the incident light. In addition to the device, P3HT:PCBM solar cells with the use of the TiO2 nanoparticles, enhanced Fill Factor (FF) due mainly to improved shunt resistance (Rsh). The TiO2 plays a critical role in improving the interface between P3HT:PCBM active layer and Al electrode.
Direct heteroarylation polymerization was employed to synthesize a novel low bandgap polymer, used as a p-type material of polymer photovoltaic cells. To achieve low bandgap of conjugated polymers, electron donor-acceptor (D-A) alternating strategy was used. The electron-donating 3-alkylthiophene and electron-withdrawing cyanothiophene were coupled to be polymerized via direct heteroarylation polymerization. The cyano moiety of the polymer backbone allowed a strong intermolecular interaction between neighboring chains and improved the structural perfection of the crystal structure on the substrate. The solar cell devices of ITO/PEDOT:PSS/P3HT:PCBM/LiF/Al were fabricated on ITO-coated glass substrate.
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.
Blackberry is a fruiting berry species with very high nutrient contents. With the recent increasing consumer demand for blackberries, new sources of germplasm and breeding techniques are required to improve blackberry production. This study was carried out to evaluate the genetic diversity (GD) and relationship among 55 blackberry (Rubus fruticosus) mutants derived from γ-ray treatment (52 lines) and N-methyl-N′-nitrosourea (MNU) treatment (three lines) using an inter-simple sequence repeat marker. A total of 18 bands were amplified with an average of 3.6 bands per primer. Among them, eight bands were identified to be polymorphic with a rate of 44.4%. In addition, the GD information content values were highest in the 60 Gy treatment population and the GD values were higher in the γ-ray treatment populations than in the MNU treatment population. According to a cluster analysis, all the mutant lines can be classified into five categories, and the genetic distance was greatest between the 80 Gy-irradiated population and other populations. These results indicate that mutant lines have high GD and can be effectively utilized for improving blackberry breeding.
To apply the superconducting wire to power machines, it is necessary to conduct research on the characteristics of wire phase changes in connection with insulating layers. In this study, according to the presence or absence of insulating layers in the wire, and to the thickness of such layers, the wire's resistance increase trends and the characteristics of its recovery from quenching were examined by current-applied cycle at the temperatures of 90 K, 180 K and 250 K. Towards this end, YBCO thin-film wires that have the same critical temperatures and that have copper and stainless-steel stabilizing layers were prepared. One level and three and five levels of superior-performance polyimide pressure-sensitive adhesive tape was attached to the wires at a very low temperature. The eight prepared test samples were wound around the linear frames, then the wire's voltage and current created owing to the phase change characteristics were measured at each prescribed temperature, using the four-point probe method. Further, near the examination temperatures of 90 K, 180 K and 250 K the wire's resistance and recovery characteristics were examined by cycle.
To enhance the lifetime of large-sized active matrix organic light emitting
diodes (AMOLEDs), we developed a liquid desiccant for encapsulation. The
liquid desiccant was prepared by mixing nano-sized calcium oxide (CaO)
powders and silicone binder including polyalkylalkenylsiloxane,
polyalkylhydrogensiloxane and platinum compound. It was confirmed that
liquid desiccant had an effect on absorption of penetrated moisture and
oxygen through calcium tests. Also, the test cells encapsulated with only
epoxy sealant dispensed at the edge of the cell developed dark spots within
100 hrs, which grew larger with time at 85 oC and 85 % R.H. On the other hand, the test cell sealed with epoxy
sealant and liquid desiccant showed no dark spots and retained 97% of its
initial luminance even after being stored for 800 hrs at 85 oC and 85 % R.H. Furthermore, the accelerating storage lifetimes of
31-inch bottom-emitting AMOLEDs with epoxy sealant and liquid desiccant
showed about 1000 hrs. These results suggest that the liquid desiccant can
be applied to encapsulation of large-sized AMOLEDs.
Diamond like carbon (DLC) coatings have attracted great attention for use in various applications in automobile industry and machinery because they have excellent properties such as low friction coefficient and ultra high strength. The low friction coefficient of DLC comes from anti-adhesion with other materials, smooth surface, lubrication of graphite structure at the contacting point of films, and the hydrogen content of the films. Many researches have been focused on the microstructure effects on the tribological properties of DLC films but few have been reported on the effect of hydrogen content. In this study, the effect of hydrogen content on the friction coefficient of DLC films has been investigated.
DLC films have been deposited on D2 steel by plasma enhanced CVD (Pulsed DC PECVD) method with different precursor gas of C2H2 and CH4 and different gas pressure. The effects of gas composition on the hydrogen content in DLC films and the resulting tribological properties have been reviewed. Si interlayer was deposited on D2 to improve adhesion of DLC on steel substrates. The characteristics of microstructure were evaluated by Raman spectroscope and composition was measured by RBS and EDS. The tribological behaviors of DLC films were investigated using ball on disk tribometer. The hardness of films was examined by nano-indenter. The failure mechanism of DLC deposited on steel substrates was examined using optical microscope and SEM/EDS. The results showed that the friction coefficient of DLC films deposited with C2H2 was 0.06 and that of the film with CH4 was 0.15. The friction coefficient improved with decreasing hydrogen content in DLC films.
The morphology evolution of thin films was studied by molecular dynamics simulation. In this simulation four deposition and substrate elements combinations were used: Al on Al(001), Al on Co(001), Co on Co(001), Co on Al(001). The Al thin film was always grown by layer-bylayer mode regardless of substrates used. On the other hand, thin films formed by Co deposition depended on substrates used.While Co thin films on the Co substrates were grown by the island mode, a 3 monolayer (ML) thickness of CoAl surface compound was initially formed on Al substrate, before pure Co thin film growth occurred. In addition to the study on morphologies, the degrees of mixing of atoms in the interface were studied quantitatively. No surface mixing and a sharp interface were observed when Co was used as a substrate regardless of deposited atoms. On the contrary, a large amount of surface mixing or compound formation was observed when Al was used as a substrate.
The complex dielectric constants of several π-conjugated materials were measured, and generalized Langevin equation was used to analyze the dielectric behavior in the frequency domain. From the results of the fitting the experimental data using the generalized Langevin equation, we suggest that the charge carriers are electrically screened by the neighboring charges through the structural relaxation, and the carriers are not interact each other. We confirmed that the generalized Langevin equation offers a very good approach to analyze and understand the transport properties of charge carriers in π-conjugated materials.
We have fabricated the a-Si:H film for pixel region and poly-Si film for driver region on the same glass substrate by a rapid thermal process successfully. By employing the halogen lamp, the considerable amount of hydrogen in the PECVD a-Si:H film, which causes the undesirable film ablation due to hydrogen evolution during excimer laser annealing, could be reduced selectively in the peripheral driver area where the a-Si:H film is recrystallized into poly-Si film in order to obtain the high mobility. After rapid thermal annealing, the hydrogen content in a-Si:H films, of which the inherent hydrogen content was found to be about 10–12 at. %, is successfully reduced to less than 5 at. %. The annealing conditions for dehydrogenation are 500, 550, 600 and 650 °C with various halogen lamp irradiation period which are below the point of the glass shrinkage. It should be noted that after rapid thermal annealing, any physical damage in the glass substrate has not been observed.
Ferroelectric BaTiO 3 thin films with perovskite structure were grown by sol-gel spin-on processing onto (111)Pt/Ti/SiO2/Si substrates. In order to investigate the effects of space charge in BaTiO3 thin films, we measured the relative dielectric constant and the ac conductivity of the films as a function of frequency, ac oscillation amplitude and temperature. Dielectric constant and dielectric loss were 147 and 0.03 at 100 kHz, respectively. Also, BaTiO3 thin films exhibited marked dielectric relaxation above the Curie temperature and in the low frequency region below 100 Hz. This low frequency dielectric relaxation is attributed to the ionized space charge carriers such as oxygen vacancies and defects in BaTiO3 film and the interfaical polarization. The thermal activation energy for the relaxation process of the ionized space charge carriers was 0.72 eV.
Highly hydrophobic fluorocarbon films were prepared by the vapor phase (VP) deposition method in a vacuum chamber using both liquid (3M's FC40, FC722) and solid sources (perfluorodecanoic acid (CF3(CF2)8COOH), perfluorododecane (C12F26)) on Al, Si and oxide coated wafers. The highest static contact angles of water were measured on films deposited on aluminum substrate. But relatively lower contact angles were obtained on the films on Si and oxide wafers. The advancing and receding contact angle analysis using a captive drop method showed a large contact angle hysteresis (ΔH) on the VP deposited fluorocarbon films. AFM study showed poor film coverage on the surface with large hysteresis. FTIR-ATR analysis positively revealed the stretching band of CF2 groups on the VP deposited substrates. The thermal stability of films was measured at 150°C in air and nitrogen atmospheres as a function of time. The rapid decrease of contact angles was observed on VP deposited FC and PFDA films in air. However, no decrease of contact angle on them was observed in N2.
The performance of polysilicon thin film transistors fabricated by two-step annealing, which consists of furnace annealing and subsequent excimer laser annealing, is described. It was found that the average grain size of low temperature furnace annealed polysilicon films was several times larger than that of excimer laser annealed polysilicon films while the density of in-grain defect in low temperature furnace annealed films was much higher than that of excimer laser annealed film. The device characteristics of the low temperature furnace annealed polysilicon thin film transistors were improved significantly by postannealing, such as high temperature furnace annealing and excimer laser annealing, due to the effective elimination of in-grain defects. The density of trap states, which was extracted from the transfer curves of polysilicon thin film transistors, was used to demonstrate the effects of modifying the deep and tail trap levels by two-step annealing.
This paper reports the development and characterization of PZT nanofibers with average diameters ranged from 50 to 150 nm for various sensing and actuation applications. PZT nano fibers have been developed by sol-gel electrospinning process. Both randomly distributed and uniaxially aligned PZT fibers were obtained from the sol-gel solution with viscosity modified by polyvinyl pyrrolidone (PVP). The diameters of the nano fibers can be further reduced or controlled for different applications. The morphology and structure of the nanofibers were examined with SEM, TEM and XRD. We used two-step process to anneal the electrospun fibers and XRD confirmed that pure perovskite phase was formed after the as-spun fibers being annealed at about 650°C. TEM results showed that the grain size of the fibers was about 10 nm. Microelectromechanical (MEMS) based micro-fabrication technologies were used to assist the development of the nano-fibers in designing the test samples, depositing and patterning the electrodes, and also testing the performance of the nano fibers. Different approaches have been explored to fabricate the uniaxially aligned nano fibers. SEM results showed that partial aligned PZT nano-fibers were obtained on the pre-patterned substrats. Interdigitated Electrodes were evaporated on the partial aligned fibers by using shadow mask. Hysteresis curve of the nano piezoelectric fibers was also obtained, however further tests are still needed to get accurate measurement. The obtained PZT nanofibers have promising application potentials in designing and enabling micro and nano devices.