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We investigated gender differences in psychosocial determinants that affect hand hygiene (HH) performance among physicians.
The survey included a structured questionnaire with 7 parts: self-assessment of HH execution rate; knowledge, attitude, and behavior regarding HH; internal and emotional motivation for better HH; barriers to HH; need for external reminders; preference for alcohol gel; and embarrassment due to supervision.
The study was conducted across 4 academic referral hospitals in Korea.
Physicians who worked at these hospitals were surveyed.
The survey questionnaire was sent to 994 physicians of the hospitals in July 2018 via email or paper. Differences in psychosocial determinants of HH among physicians were analyzed by gender using an independent t test or the Fisher exact test.
Of the 994 physicians, 201 (20.2%) responded to the survey. Among them, 129 (63.5%) were men. Male physicians identified 4 barriers as significant: time wasted on HH (P = .034); HH is not a habit (P = .004); often forgetting about HH situations (P = .002); and no disadvantage when I do not perform HH (P = .005). Female physicians identified pain and dryness of the hands as a significant obstacle (P = .010), and they had a higher tendency to feel uncomfortable when a fellow employee performed inadequate HH (P = .098). Among the respondents, 26.6% identified diversifying the types of hand sanitizers as their first choice for overcoming barriers to improving HH, followed by providing reminders (15.6%) and soap and paper towels in each hospital room (13.0%).
A significant difference in the barriers to HH existed between male and female physicians. Promoting HH activities could help increase HH compliance.
Mood disorders require consistent management of symptoms to prevent recurrences of mood episodes. Circadian rhythm (CR) disruption is a key symptom of mood disorders to be proactively managed to prevent mood episode recurrences. This study aims to predict impending mood episodes recurrences using digital phenotypes related to CR obtained from wearable devices and smartphones.
The study is a multicenter, nationwide, prospective, observational study with major depressive disorder, bipolar disorder I, and bipolar II disorder. A total of 495 patients were recruited from eight hospitals in South Korea. Patients were followed up for an average of 279.7 days (a total sample of 75 506 days) with wearable devices and smartphones and with clinical interviews conducted every 3 months. Algorithms predicting impending mood episodes were developed with machine learning. Algorithm-predicted mood episodes were then compared to those identified through face-to-face clinical interviews incorporating ecological momentary assessments of daily mood and energy.
Two hundred seventy mood episodes recurred in 135 subjects during the follow-up period. The prediction accuracies for impending major depressive episodes, manic episodes, and hypomanic episodes for the next 3 days were 90.1, 92.6, and 93.0%, with the area under the curve values of 0.937, 0.957, and 0.963, respectively.
We predicted the onset of mood episode recurrences exclusively using digital phenotypes. Specifically, phenotypes indicating CR misalignment contributed the most to the prediction of episodes recurrences. Our findings suggest that monitoring of CR using digital devices can be useful in preventing and treating mood disorders.
Patients with mental illness are vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection because of behavioural changes associated with cognitive deterioration, especially without their caregivers. While studies have reported that SARS-CoV-2 infection risk and severe clinical outcomes are high among patients with mental illness, there is a lack of quantitative research supporting this claim. This study investigates if SARS-CoV-2 infection and coronavirus disease 2019 (COVID-19)-related death are higher in patients with mental illness than among those without a mental disorder.
A cohort study was conducted using the COVID-19 database of the National Health Insurance Service in South Korea. A total of 123 480 patients aged ⩾20 years who visited a hospital between 1 January 2020 and 30 May 2020 were analysed. Mental disorder diagnoses and types were determined based on 2019 medical records, and a multivariate logistic regression model was used to calculate the odds ratios (ORs) for SARS-CoV-2 infection and deaths.
The ORs for SARS-CoV-2 infection (OR 1.58; 95% CI 1.45–1.71) and COVID-19-related death (OR 2.18; 95% CI 1.57–3.04) were high among patients with mental illness. The OR of SARS-CoV-2 infection was higher among patients with severe mental illness (OR 2.60; 95% CI 2.21–3.06), dementia (OR 1.90; 95% CI 1.62–2.22) and substance use disorder (OR 4.98, 95% CI 3.60–6.88). The OR for COVID-19-related death was high among patients with severe mental illness (OR 3.53; 95% CI 1.82–6.83) and dementia (OR 2.12; 95% CI 1.39–3.22).
Patients with mental illness are at high risk for SARS-CoV-2 infection and COVID-19-related death. Behavioural changes associated with cognitive deterioration and long-term care facility residence increase SARS-CoV-2 infection risk, and severe medical conditions and delayed treatment increase the COVID-19-related mortality risk in patients with mental illness. Patients with mental illness are a priority target population for COVID-19 prevention and treatment, and it is important to plan prevention measures that address their needs.
The experiments reported in this research paper aimed to determine the effect of supplementing different forms of L-methionine (L-Met) and acetate on protein synthesis in immortalized bovine mammary epithelial cell line (MAC-T cells). Treatments were Control, L-Met, conjugated L-Met and acetate (CMA), and non-conjugated L-Met and Acetate (NMA). Protein synthesis mechanism was determined by omics method. NMA group had the highest protein content in the media and CSN2 mRNA expression levels (P < 0.05). The number of upregulated and downregulated proteins observed were 39 and 77 in L-Met group, 62 and 80 in CMA group and 50 and 81 in NMA group from 448 proteins, respectively (P < 0.05). L-Met, NMA and CMA treatments stimulated pathways related to protein and energy metabolism (P < 0.05). Metabolomic analysis also revealed that L-Met, CMA and NMA treatments resulted in increases of several metabolites (P < 0.05). In conclusion, NMA treatment increased protein concentration and expression level of CSN2 mRNA in MAC-T cells compared to control as well as L-Met and CMA treatments through increased expression of milk protein synthesis-related genes and production of the proteins and metabolites involved in energy and protein synthesis pathways.
Depressive symptoms are common in bereaved caregivers; however, there have been few prospective studies using a structured interview. This study investigated the prevalence and preloss predictors of major depressive disorder (MDD) in bereaved caregivers of patients in a palliative care unit.
This prospective cohort study collected caregiver sociodemographic and psychological data before the death of a palliative care unit patient, including MDD, care-burden, coping style, and hopeful attitude. Postloss MDD was assessed 6 and 13 months after death, and a multivariate logistic regression analysis was conducted to identify its predictors.
Of 305 caregivers contacted, 92 participated in this study. The prevalence of preloss MDD was 21.8%; the prevalences of postloss MDD were 34.8% and 24.7% at 6 and 13 months, respectively. Preloss MDD predicted postloss MDD at 6 months (odds ratio [OR] = 5.38, 95% confidence interval [CI95%] = 1.29, 22.43); preloss nonhopeful attitude and unemployment status of caregivers predicted postloss MDD at 13 months (OR = 8.77, CI95% = 1.87, 41.13 and OR = 7.10, CI95% = 1.28, 39.36, respectively).
Significance of results
Approximately 35% of caregivers suffered from MDD at 6 months postloss, but the prevalence of MDD decreased to about 25% at 13 months. Preloss MDD significantly predicted postloss MDD at 6 months, whereas hopeful attitude and unemployment at baseline were significantly associated with postloss MDD at 13 months.
Adult onset tic disorders are usually secondary in origin. We report a case of adult onset tic disorder following carbon monoxide (CO) intoxication with typical magnetic resonance imaging features.
A 36-year-old woman developed temporarily suppressible patterned movements on her face, neck, and shoulder associated with sensory discomfort after CO poisoning. Magnetic resonance images showed bilateral symmetric cavitary changes in the globus pallidus. Clonazepam relieved much of her symptoms.
Our patient developed a mono-symptomatic tic disorder following CO intoxication. This further supports that altered outflow signals from the basal ganglia, especially the globus pallidus, may contribute to the development of tic disorders.
A number of causative mutations such as a-synuclein, parkin, UCHL1, Pink-1, DJ-1 have been identified in Parkinson's disease (PD). They are usually found in the familial cases. One mutation of great interest is the G2019S mutation in the LRRK2 gene, which has been reported in both familial and sporadic PD. Its prevalence has been reported to vary markedly among different races. We examined the prevalence of the G2019S mutation in the Korean PD population for genetic study planning.
We conducted a genetic analysis of the G2019S mutation by standard PCR and restriction digestion method. 453 PD patients were studied, 34% of whom had an age at onset of <50 years and 3.8% had a positive family history.
None of the 453 study subjects carried the G2019S mutation.
Our result confirms previous reports that the G2019S mutation is rare among PD patients in the Asian population. This result supports the notion that the prevalence of this LRRK2 mutation is population specific, and that there may be a founder effect within western populations.
There is increasing evidence of a relationship between underweight or obesity and dementia risk. Several studies have investigated the relationship between body weight and brain atrophy, a pathological change preceding dementia, but their results are inconsistent. Therefore, we aimed to evaluate the relationship between body mass index (BMI) and cortical atrophy among cognitively normal participants.
We recruited cognitively normal participants (n = 1,111) who underwent medical checkups and detailed neurologic screening, including magnetic resonance imaging (MRI) in the health screening visits between September 2008 and December 2011. The main outcome was cortical thickness measured using MRI. The number of subjects with five BMI groups in men/women was 9/9, 148/258, 185/128, 149/111, and 64/50 in underweight, normal, overweight, mild obesity, and moderate to severe obesity, respectively. Linear and non-linear relationships between BMI and cortical thickness were examined using multiple linear regression analysis and generalized additive models after adjustment for potential confounders.
Among men, underweight participants showed significant cortical thinning in the frontal and temporal regions compared to normal weight participants, while overweight and mildly obese participants had greater cortical thicknesses in the frontal region and the frontal, temporal, and occipital regions, respectively. However, cortical thickness in each brain region was not significantly different in normal weight and moderate to severe obesity groups. Among women, the association between BMI and cortical thickness was not statistically significant.
Our findings suggested that underweight might be an important risk factor for pathological changes in the brain, while overweight or mild obesity may be inversely associated with cortical atrophy in cognitively normal elderly males.
Epidemiological studies have reported that higher education (HE) is associated with a reduced risk of incident Alzheimer's disease (AD). However, after the clinical onset of AD, patients with HE levels show more rapid cognitive decline than patients with lower education (LE) levels. Although education level and cognition have been linked, there have been few longitudinal studies investigating the relationship between education level and cortical decline in patients with AD. The aim of this study was to compare the topography of cortical atrophy longitudinally between AD patients with HE (HE-AD) and AD patients with LE (LE-AD).
We prospectively recruited 36 patients with early-stage AD and 14 normal controls. The patients were classified into two groups according to educational level, 23 HE-AD (>9 years) and 13 LE-AD (≤9 years).
As AD progressed over the 5-year longitudinal follow-ups, the HE-AD showed a significant group-by-time interaction in the right dorsolateral frontal and precuneus, and the left parahippocampal regions compared to the LE-AD.
Our study reveals that the preliminary longitudinal effect of HE accelerates cortical atrophy in AD patients over time, which underlines the importance of education level for predicting prognosis.
The synthesis, structure, and electrical performances of titanium dioxide (TiO2 and also doped TiO2) thin films, a capacitor dielectric for dynamic random access memory (DRAM) and a resistance switching material in resistance switching RAM (ReRAM), are reviewed. The three-dimensionality of these structures and the extremely small feature sizes (<20 nm) of these memory devices require the synthesis method of TiO2-based layers to exhibit high degree of conformality. Atomic layer deposition is, therefore, the method of choice in respect of film growth for these applications. The unique arrangement of the TiO6-octahedra in the rutile structure, which results in the value for dielectric constant of the dielectric layer, εr (>100), makes the material especially attractive as the capacitor dielectric layer in DRAM. Removing some of the oxygen ions from the rutile structure and arranging the resulting oxygen vacancies on a specific crystallographic plane results in the so called Magnéli phase materials, which show distinctive conducting semiconductor or metallic characteristics. External electrical stimuli can cause the repeated formation and rupture of conducting channels that consist of these Magnéli phase materials in the insulating TiO2 matrix, and this aspect makes the material a very feasible choice for applications in ReRAM. This article reviews the material properties, fabrication process, integration issues, and prospect of TiO2 films for these applications.
The effects of tannic acid (TA) supplementation (0·02 %, wt/wt) were compared with the effects of clofibrate (CF) supplementation (0·02 %, wt/wt) in apo E-deficient (apo E− / −) mice fed a AIN-76 semi-synthetic diet (normal diet) over 20 weeks. The mice were monitored for the modulation of hepatic mRNA expression and the activities of lipid-regulating enzymes. Both TA and CF supplementation lowered hepatic 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR) activity and prevented atherosclerotic lesion formation in comparison with the control group. Hepatic carnitine palmitoyl transferase and β-oxidation activities were significantly higher in the TA and CF groups than in the control group. Both CF and TA supplementation resulted in significant decreases in hepatic HMGR mRNA levels in association with its enzyme activity. However, in contrast to CF supplementation, TA supplementation seemed to decrease the accumulation of hepatic lipids in the apo E− / − mice without increasing liver weight. These results suggest that the overall effect of TA is more desirable than CF for the alleviation of hepatic lipogenesis and atherogenesis in apo E− / − mice.
The diatoms are an ecologically important group of algae that have been extensively studied by ecologists and taxonomists. However, the large-scale patterns of diatom distribution and the factors underlying this distribution are largely unknown. The aims of this study were to identify the large-scale spatial patterns of benthic diatom assemblages in Korean streams and rivers, and to assess the importance of numerous environmental factors on diatom distribution. We classified 720 study sites based on diatom flora. Benthic diatoms, water chemistry, altitude, and riparian land cover and use were characterized by multivariate analyses, Monte Carlo permutation tests, and indicator species analysis. In total, we identified 531 diatom taxa. Diatom assemblages were mostly dominated by species of the genera Achnanthes, Navicula, Nitzschia, Cocconeis, Fragilaria (Synedra included), Cymbella, Gomphonema, and Melosira. Cluster analysis partitioned all 720 sites into eight groups based on diatom species composition. Canonical correspondence analysis indicated that altitude, land cover and use, current velocity, electrical conductivity, and nutrient levels explained a significant amount of the variation in the composition of assemblages of benthic diatoms. At the national scale, a downstream ecological gradient was apparent, from fast-flowing, mostly oligotrophic highland streams to slow-flowing, mostly eutrophic lowland rivers. Our data suggest that spatial factors explain some of the variation in diatom distribution. The present investigation of the spatial patterns of benthic diatoms, the ecological determinants of diatom occurrence, and the identification of diatom indicator species contributes to development of a program for assessing the biological integrity of lotic ecosystems in Korea.
While it is well known that picture naming (PN) is impaired in Alzheimer’s disease (AD), sound naming (SN) has not been thoroughly investigated. We postulated that SN might be impaired more severely and earlier than PN, given the early involvement of the temporal cortex by AD-related pathology. SN and PN were assessed in 21 normal participants, 40 patients with mild cognitive impairment (MCI), and 27 patients in early stages of AD. Our results showed that SN accuracy and latency were more sensitive to advancing pathology in AD than PN accuracy and latency. SN was more useful and specific in distinguishing MCI patients from normal participants and therefore in potentially identifying the subset of MCI patients who already have impairment in more than one cognitive domain and may actually have incipient AD. These findings indicate a potential diagnostic utility of SN for early detection of the disease. Furthermore, even though most AD patients demonstrated more or less comparable impairment in both tasks, some were disproportionately impaired on SN and others were differentially impaired on PN. Future studies may be able to show that these discrepant groups correspond to patients with right and left hemisphere predominant AD, respectively. (JINS, 2009, 15, 231–238.)
Plasma doping (PLAD) process utilizing PH3 plasma to fabricate n-type junction with supplied bias of −1 kV and doping time of 60 sec under the room temperature is presented. The RTA process is performed at 900 °C for 10 sec. A defect-free surface is corroborated by TEM and DXRD analyses, and examined SIMS profiles reveal that shallow n+ junctions are formed with surface doping concentration of 1021atoms/cm3. The junction depth increases in proportion to the O2 gas flow when the N2 flow is fixed during the RTA process, resulting in a decreased sheet resistance. Measured doping profiles and the sheet resistance confirm that the n+ junction depth less than 52 nm and minimum sheet resistance of 313 Ω/□ are feasible.
NiCr films were thermally evaporated on the Mn-Ni-Co-O thick-film substrates. The NiCr/Mn-Ni-Co-O bi-layer systems were tested in a thermal shock chamber with three temperature differences of 150, 175 and 200°C. The systems were considered to have failed when the sheet resistance of NiCr films changed by 30% relative to an initial value. As the cyclic repetition of thermal shock increased, the sheet resistance of NiCr coatings increased. The Coffin-Manson equation was applied to the failure mechanism of cracking of NiCr coatings and the SEM observation of cracks and delamination in NiCr coatings due to thermal cycling agreed well with the failure mechanism.
We report new lateral grain growth mechanism by XeCl excimer laser annealing on a-Si film with pre-patterned Al layer. 2000Å-thick Al pattern on 800Å-thick PECVD a-Si film successfully reflects the incident laser beam and results in temperature gradient during the recrystallization process. The TEM images show that grain growth near the boundary between the liquid and the solid region exhibits a different mechanism compared with the conventional ELA. About 1.5 m-long lateral grain has been successfully obtained by single laser irradiation
A poly-Si TFT with single grain boundary in the channel has been fabricated by the proposed excimer laser annealing. An excellent device characteristics such as mobility more than 250cm2/Vsec, high On/Off current ratio of 6.3×106 and low threshold voltage less than 1 V has been obtained. The experimental results show that the mobility, threshold voltage and sub-threshold slope of proposed TFTs are superior to those of the conventional TFTs.
Surface pretreatment using Cl2 plasma was applied to n-type GaN and Ti/Al ohmic contacts with resistivity of ~ 10−6 Ω cm2, realized without annealing. Using synchrotron radiation photoemission spectroscopy, it was observed that the Fermi level moved by 0.5 eV toward the conduction band edge and the atomic ratio of Ga/N was increased by the treatment. This suggests that a number of N vacancies were produced at the treated surface and the Fermi level was pinned at the energy level of N vacancies near the conduction band. The N vacancies acting as donors for electrons produced a number of electrons, resulting in the near surface region to be in the degenerate state. Both the shift of Fermi level and the production of electrons at the treated surface lead to the reduction in contact resistivity through the decrease of the effective Schottky barrier for conduction of electrons.
A new excimer laser recrystallization method of amorphous silicon is proposed to increase the grain size and control the grain boundary locations in polycrystalline silicon films. The proposed method is based on the lateral grain growth which occurs at the interface between molten and unmolten regions. To obtain selectively molten regions, the proposed method employs aluminum patterns on amorphous silicon. The aluminum patterns act as the beam shield during the laser irradiation as well as the lateral heat sink during the solidification period. The high reflectance of aluminum at the wavelength of XeCl excimer laser offers stable beam shielding property, and the high thermal conductivity enhances the lateral heat flow by the quick draining of laterally propagated heat. TEM observation has revealed that the well arranged large grains were successfully obtained.
A new excimer laser annealing method is proposed in order to produce the poly-Si film with low defect density and large grain, by combining the selective Si ionimplantation and excimer laser annealing. Selective Si ion-implantation is employed to form artificial nucleation seeds in a-Si film prior to excimer laser annealing in order to increase the nucleation probability. The grain boundary location in poly-Si film has been controlled through implantation mask, and the grain size around micrometer order is obtained without any other process. TEM result shows that grain boundary is controlled according to mask pattern and the crystallinity of the poly-Si film is improved.