Effect of a ZrO2 Seed Layer on an Hf0.5Zr0.5O2 Ferroelectric Device Fabricated via Plasma Enhanced Atomic Layer Deposition.

In this study, a ferroelectric layer was formed on a ferroelectric device via plasma enhanced atomic layer deposition. The device used 50 nm thick TiN as upper and lower electrodes, and an Hf0.5Zr0.5O2 (HZO) ferroelectric material was applied to fabricate a metal-ferroelectric-metal-type capacitor. HZO ferroelectric devices were fabricated in accordance with three principles to improve their ferroelectric properties. First, the HZO nanolaminate thickness of the ferroelectric layers was varied. Second, heat treatment was performed at 450, 550, and 650 °C to investigate the changes in the ferroelectric characteristics as a function of the heat-treatment temperature. Finally, ferroelectric thin films were formed with or without seed layers. Electrical characteristics such as the I-E characteristics, P-E hysteresis, and fatigue endurance were analyzed using a semiconductor parameter analyzer. The crystallinity, component ratio, and thickness of the nanolaminates of the ferroelectric thin film were analyzed via X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy. The residual polarization of the (20,20)*3 device heat treated at 550 °C was 23.94 µC/cm2, whereas that of the D(20,20)*3 device was 28.18 µC/cm2, which improved the characteristics. In addition, in the fatigue endurance test, the wake-up effect was observed in specimens with bottom and dual seed layers, which exhibited excellent durability after 108 cycles.

Renal tissue elasticity by acoustic radiation force impulse: A prospective study of healthy kidney donors.

BACKGROUND: Some studies reported the correlations between renal parenchymal stiffness measured by transient elastography or acoustic radiation force impulse (ARFI) and the extent of interstitial fibrosis. This study was prospectively designed to evaluate the correlation between clinical, histological findings and the kidney shear wave velocity (SWV, m/s) assessed by ARFI elastography to identify factors affecting the kidney SWV in normal patients. METHODS: Seventy-three adult living kidney transplantation donors were enrolled in our center between September 2010 and January 2013. Before transplantation, all donors were evaluated by ARFI elastography to identify the range of SWV in kidneys. Time-zero biopsies were performed on all graft kidneys before implantation. RESULTS: Mean age of donors was 42.0 ±â€Š11.3 years. The mean SWV and depth were 2.21 ±â€Š0.58 m/s and 5.37 ±â€Š1.06 cm. All histological findings showed mild degree of the Banff score, only grade I. In univariate analyses, the SWV was not associated with all histological parameters. Age (r = -0.274, P = .019) diastolic blood pressure (DBP, r = -0.255, P = .030) and depth for SWV measurement (r = -0.345, P = .003) were significantly correlated with the SWV. In multivariate linear regression analysis, age, gender, body mass index (BMI), and depth for SWV measurement were significantly correlated with the SWV (P = .003, .005, .002, and .004, respectively). CONCLUSIONS: We demonstrated that all histological findings are not correlated with the SWV of donor kidney. Otherwise, factors influencing the kidney SWV assessed by ARFI elastography are age, gender, BMI, and depth for the SWV measurement in donors for kidney transplantation.

Mediating Role of Anxiety and Depression in the Relationship between Posttraumatic Stress Symptoms and Illness Intrusiveness.

BACKGROUND: Posttraumatic stress symptoms (PTSS) in patients with psychological trauma lead to poor health-related quality of life. Understanding of the relationships among PTSS, anxiety, depression, and illness intrusiveness will guide the development of efficient approaches to enhance subjective well-being in patients with psychological trauma. This study investigated whether anxiety and depression mediate the relationship between PTSS and illness intrusiveness in the hope of providing more comprehensive and effective trauma treatment. METHODS: Psychiatric outpatients who visited the trauma clinic of a university hospital (n = 260) participated in this study. Assessments were conducted for PTSS, anxiety, depression, and illness intrusiveness. Structural equation modeling and path analysis were performed to analyze the mediating effects of anxiety and depression on the relationship between PTSS and illness intrusiveness. RESULTS: PTSS had both direct and indirect exacerbating effects on illness intrusiveness. Anxiety exhibited the largest direct exacerbating effect on illness intrusiveness. The indirect effects of PTSS on illness intrusiveness through anxiety alone and through a depression-to-anxiety pathway were significant, but the indirect effect through depression alone was not. CONCLUSION: The findings demonstrate that anxiety, both independently and as part of an interrelated pathway with depression, partially mediates the relationship between PTSS and illness intrusiveness. Appropriate interventions and a comprehensive approach to alleviate anxiety and depression could mitigate the negative effects of PTSS on illness intrusiveness in patients with psychological trauma.

Attachment insecurity as a mediator of the relationship between childhood trauma and adult dissociation.

This study aimed to investigate whether attachment insecurity mediates the relationship between childhood trauma and adult dissociation, specifically with regard to individual forms of childhood maltreatment. Psychiatric outpatients who visited a specialized trauma clinic (n = 115) participated in the study. Data were collected via the Childhood Trauma Questionnaire, Revised Adult Attachment Scale, and Dissociative Experience Scale. Structural equation modeling and path analysis were performed to analyze the mediating effects of attachment insecurity on the relationship between childhood trauma and adult dissociation. Greater childhood trauma was associated with higher dissociation, and the relationship between them was fully mediated by attachment anxiety. In path analysis of trauma subtypes, the effects of emotional abuse, physical abuse, and physical neglect as a child on adult dissociation were found to be fully mediated by attachment anxiety. The effect of sexual abuse on dissociation was mediated by a synergistic effect from both attachment anxiety and attachment avoidance. Regarding emotional neglect, a countervailing interaction was discovered between the direct and indirect effects thereof on dissociation; the indirect effect of emotional neglect on dissociation was partially mediated by attachment insecurity. Specific aspects of attachment insecurity may help explain the relationships between individual forms of childhood trauma and adult dissociative symptoms. Tailored treatments based on affected areas of attachment insecurity may improve outcomes among patients with dissociative symptoms and a history of childhood trauma.

Short-term Evaluation of a Comprehensive Education Program Including Inhaler Training and Disease Management on Chronic Obstructive Pulmonary Disease.

BACKGROUND: Proper education regarding inhaler usage and optimal management of chronic obstructive pulmonary disease (COPD) is essential for effectively treating patients with COPD. This study was conducted to evaluate the effects of a comprehensive education program including inhaler training and COPD management. METHODS: We enlisted 127 patients with COPD on an outpatient basis at 43 private clinics in Korea. The patients were educated on inhaler usage and disease management for three visits across 2 weeks. Physicians and patients were administered a COPD assessment test (CAT) and questionnaires about the correct usage of inhalers and management of COPD before commencement of this program and after their third visit. RESULTS: The outcomes of 127 COPD patients were analyzed. CAT scores (19.6±12.5 vs. 15.1±12.3) improved significantly after this program (p<0.05). Patients with improved CAT scores of 4 points or more had a better understanding of COPD management and the correct technique for using inhalers than those who did not have improved CAT scores (p<0.05). CONCLUSION: A comprehensive education program including inhaler training and COPD management at a primary care setting improved CAT scores and led to patients' better understanding of COPD management.

Depression and insomnia as mediators of the relationship between distress and quality of life in cancer patients.

BACKGROUND: Distress in cancer patients leads to poorer quality of life (QOL) and negatively impacts survival. For efficient management of a patient's disease course, the interrelationships among distress, depression, insomnia, and QOL must be understood. This study aimed to investigate whether depression and insomnia mediate the relationship between distress and QOL in cancer patients. METHODS: Cancer patients referred to a specialized psycho-oncology clinic (n=208) participated in this study. Distress, depression, insomnia, and QOL were measured with the following questionnaires: Distress Thermometer, Hospital Anxiety and Depression Scale, Insomnia Severity Index, and Functional Assessment of Cancer Therapy-General. Structural equation modeling and path analysis were performed to analyze the mediating effects of depression and insomnia on the relationship between distress and QOL. RESULTS: Distress exerted nearly equal direct (ß=-0.291, p=0.002) and indirect (mediated by depression and insomnia) (ß=-0.299, p=0.003) negative effects on QOL. Depression exhibited the largest direct negative effect on QOL. The indirect effects of distress on QOL through depression alone, through insomnia alone, and through an insomnia to depression pathway were all significant (ß=-0.122, p=0.011; ß=-0.102, p=0.002; and ß=-0.075, p<0.001, respectively). LIMITATIONS: The cross-sectional analyses limit the measurement of causal relationships between each variable. CONCLUSIONS: Depression and insomnia, both individually and as part of an interrelated pathway, partially mediate the relationship between distress and QOL. Appropriate interventions to alleviate insomnia and depression may mitigate the negative impacts of distress on QOL in cancer patients.

Higher serum interleukin-17A levels as a potential biomarker for predicting early disease progression in patients with hepatitis B virus-associated advanced hepatocellular carcinoma treated with sorafenib.

BACKGROUND: Although sorafenib is the only available drug with proven efficacy for patients with advanced hepatocellular carcinoma (HCC), the clinical efficacy of sorafenib is variable and unpredictable. The aim of the current study was to identify potential serum biomarkers predicting cancer progression and overall survival (OS) in patients with hepatitis B virus (HBV)-related advanced HCC treated with sorafenib. METHODS: Thirty-four patients with HBV-related advanced HCC (modified Union for International Cancer Control [UICC] stage IVa or IVb) treated with sorafenib for more than 4weeks were retrospectively enrolled. Using a Luminex 200 system, 11 cytokines including interleukin-17A (IL-17A) were measured in baseline serum samples prior to sorafenib administration. Several clinical factors and the serum concentrations of the 11 cytokines were analyzed using Cox regression analysis. RESULTS: In the analysis of progression-free survival (PFS), older age (year; hazard ratio [HR]=1.07; 95% confidence interval [CI]=1.00-1.15; P=0.046) and higher baseline serum IL-17A level (>1.94pg/mL; HR=19.96; 95% CI=3.32-119.86; P=0.001) were identified as significant risk factors for early progression with good predictive power (Harrell's C=0.817, standard error estimates (se)=0.085). In the analysis of OS, higher Child-Pugh score (>5; HR=2.35, 95% CI=1.09-5.10, P=0.030) and lower serum baseline fibroblast growth factor-2 level (≤20.57pg/mL; HR=3.24, 95% CI=1.22-8.60, P=0.018) were identified as negative predictive factors for OS, even though the model did not have significant predictive power (Harrell's C=0.634, se=0.062). CONCLUSION: A higher serum IL-17A level is a potential biomarker for predicting poor PFS in patients with HBV-related advanced HCC treated with sorafenib.

Comparison of the shock absorption capacities of different mouthguards.

BACKGROUND/AIMS: In this in vitro study, the protective qualities of different mouthguard types were examined during small hard object collisions. The aim was to investigate inconclusive aspects of hard inserts, nylon nets, and air spaces as reinforcements in the anterior region and the protection qualities of ethylene vinyl acetate (EVA). MATERIALS AND METHODS: Five different mouthguards with a labial thickness between 2 mm and 11 mm made of materials of varying stiffness were investigated. As a negative control, the same experiments were performed without a mouthguard. Different combinations of EVA and labial inserts ((polyethylene terephthalate glycol-modified [PETG]), nylon mesh, air space) were tested. Using a stainless steel pendulum device, blows of different energy (0.07-2.85 joules) were applied to the center of the crown of a pivoted tooth in a custom-built jaw model. A laser Doppler vibrometer measured the tooth deflection, while an acceleration sensor attached to the pendulum measured the braking accelerations. RESULTS: Tooth deflection was reduced up to 99.7% compared to no mouthguard, and the braking acceleration was reduced up to 72.2% by increasing the mouthguards' labial thickness in combination with labial inserts of different stiffness and a built-in air space between the front teeth and the mouthguard. The mouthguards made of soft materials (EVA with nylon mesh) showed slightly better protection qualities than the more rigid mouthguards of similar thickness (PETG; P<.05). However, with increasing impact energy, their protective capacities decreased to a greater extent than the stiffer mouthguards. CONCLUSIONS: The combination of increased labial thickness and labial inserts of varying stiffness and eventually an air space offers the best protection capacities for hard, small object collisions.

Seasonal Variation, Cranial Autonomic Symptoms, and Functional Disability in Migraine: A Questionnaire-Based Study in Tertiary Care.

OBJECTIVE/BACKGROUND: Seasonal variation of migraine attack frequency has been described as a phenomenon. We aimed to compare functional disability and the occurrence of cranial autonomic symptoms (CASs) in patients who reported a seasonal variation in their migraine attack frequency with those who did not. METHODS: We conducted a questionnaire-based observational study on patients with migraine without aura who visited our institution from January 2005 to December 2013. Patient demographics, headache characteristics, and accompanying symptoms were recorded, and functional disability was evaluated by Migraine Disability Assessment (MIDAS) Questionnaire. RESULTS: Of 4423 patients screened, 769 were eligible for analysis, and 104 (13.5%) of them reported seasonal variation. Several CAS features such as conjunctival injection (25.0% vs 14.0%), lacrimation (20.2% vs 10.8%), eyelid edema (20.2% vs 10.2%), forehead and facial sweating (22.1% vs 11.4%), and ptosis (23.1% vs 11.4%) were more prominent in this subset of patients. They showed higher MIDAS scores (15.4 ± 23.5) than the other migraineurs (10.4 ± 16.9), with a 1.77-fold increased risk (95% confidence interval 1.06-2.96) of severe functional disability (MIDAS score ≥21) after adjustment for age group, sex, headache frequency, intensity, and duration. The higher the number of CASs, the greater also was the proportion of patients with severe functional disability. CONCLUSIONS: Patients who reported seasonal variation in migraine also reported more CASs and had more severe functional disability. The profound functional disability in the migraineurs reporting seasonal variation or CAS also provides direction for proactive clinical management in these patients.

The validity and reliability of the second korean working conditions survey.

BACKGROUND: The aim of this study was to evaluate the quality of the Second Korean Working Conditions Survey (KWCS), focusing on its validity and reliability. METHODS: The external validity was evaluated by the assessment of sampling procedures and the response rate, in order to investigate the representativeness of the sample. The content validity was evaluated by the assessment of the development of the questionnaire, and the consistency of questions for the selected construct. The test-retest method was used to evaluate the reliability by means of a phone call survey of 30% of the respondents, who were randomly selected. The respondents' satisfaction regarding the survey procedures and interview time were analyzed to evaluate the quality of survey data. RESULTS: The external validity was assured by an acceptable sampling procedure, rigid multi-stage stratified cluster random sampling. The content validity was also guaranteed by a reasonable procedure for the development of the questionnaire with a pretest. The internal consistency of the questions for work autonomy was maintained, with 0.738 of Cronbach's alpha. The response rate of 36% was lower than that of the European Working Conditions Survey (EWCS), with a contact rate of 66%, compared to 76% for the EWCS. The matching rates of the five retested questions were more than 98% reliable. CONCLUSION: The quality of the second KWCS was assured by the high external and content validity and reliability. The rigid sampling procedure and development of the questionnaire contributed to quality assurance. The high level of reliability may be guaranteed by the sophisticated field survey procedures and the development of a technical manual for interviewers. The technical strategies for a high response rate should be developed for future surveys.

Heat-processed ginseng enhances the cognitive function in patients with moderately severe Alzheimer's disease.

OBJECTIVES: Ginseng has been reported to improve cognitive function in animals and in healthy and cognitively impaired individuals. In this study, we investigated the efficacy of a heat-processed form of ginseng that contains more potent ginsenosides than raw ginseng in the treatment of cognitive impairment in patients with moderately severe Alzheimer's disease (AD). METHODS: Forty patients with AD were randomized into one of three different dose groups or the control group as follows: 1.5 g/day (n = 10), 3 g/day (n = 10), and 4.5 g/day (n = 10) groups, or control (n = 10). The Alzheimer's Disease Assessment Scale (ADAS) and Mini-Mental State Examination (MMSE) were used to assess cognitive function for 24 weeks. RESULTS: The treatment groups showed significant improvement on the MMSE and ADAS. Patients with higher dose group (4.5 g/day) showed improvements in ADAS cognitive, ADAS non-cognitive, and MMSE score as early as at 12 weeks, which sustained for 24-week follow-up. DISCUSSION: These results demonstrate the potential efficacy of a heat-processed form of ginseng on cognitive function and behavioral symptoms in patients with moderately severe AD.

Improvement of cognitive deficit in Alzheimer's disease patients by long term treatment with korean red ginseng.

A 24-week randomized open-label study with Korean red ginseng (KRG) showed cognitive benefits in patients with Alzheimer's disease. To further determine long-term effect of KRG, the subjects were recruited to be followed up to 2 yr. Cognitive function was evaluated every 12 wk using the Alzheimer's Disease Assessment Scale (ADAS) and the Korean version of the Mini Mental Status Examination (K-MMSE) with the maintaining dose of 4.5 g or 9.0 g KRG per d. At 24 wk, there had been a significant improvement in KRG-treated groups. In the long-term evaluation of the efficacy of KRG after 24 wk, the improved MMSE score remained without significant decline at the 48th and 96th wk. ADAS-cog showed similar findings. Maximum improvement was found around week 24. In conclusion, the effect of KRG on cognitive functions was sustained for 2 yr follow-up, indicating feasible efficacies of long-term follow-up for Alzheimer's disease.