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The COVID-19 pandemic poses a major threat to mental health and is associated with an increased risk of suicide. An understanding of suicidal behaviours during the pandemic is necessary for establishing policies to prevent suicides in such social conditions.
We aimed to investigate vulnerable individuals and the characteristics of changes in suicidal behaviour during the COVID-19 pandemic.
We retrospectively reviewed the medical records of patients with suicide attempts who visited the emergency department from February 2019 to January 2021. We analysed the demographic and clinical characteristics, risk factors and rescue factors of patients, and compared the findings between the pre-pandemic and pandemic periods.
In total, 519 patients were included. During the pre-pandemic and pandemic periods, 303 and 270 patients visited the emergency department after a suicide attempt, respectively. The proportion of suicide attempts by women (60.1% v. 69.3%, P = 0.035) and patients with a previous psychiatric illness (63.4% v. 72.9%, P = 0.006) increased during the COVID-19 pandemic. In addition, patients’ rescue scores during the pandemic were lower than those during the pre-pandemic period (12 (interquartile range: 11–13) v. 13 (interquartile range: 12–14), P < 0.001).
Women and people with previous psychiatric illnesses were more vulnerable to suicide attempts during the COVID-19 pandemic. Suicide prevention policies, such as continuous monitoring and staying in touch with vulnerable individuals, are necessary to cope with suicide risk.
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.
To investigate the feasibility of using an ultraviolet light-emitting diode (UV LED) robot for the terminal decontamination of coronavirus disease 2019 (COVID-19) patient rooms.
We assessed the presence of viral RNA in samples from environmental surfaces before and after UV LED irradiation in COVID-19 patient rooms after patient discharge.
We analyzed 216 environmental samples from 17 rooms: 2 from airborne infection isolation rooms (AIIRs) in the intensive care unit (ICU) and 15 from isolation rooms in the community treatment center (CTC). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA was detected in 40 (18.5%) of 216 samples after patient discharge: 12 (33.3%) of 36 samples from AIIRs in the ICU, and 28 (15.6%) of 180 samples from isolation rooms in the CTC. In 1 AIIR, all samples were PCR negative after UV LED irradiation. In the CTC rooms, 14 (8.6%) of the 163 samples were PCR positive after UV LED irradiation. However, viable virus was not recovered from the culture of any of the PCR-positive samples.
Although no viable virus was recovered, SARS-CoV-2 RNA was detected on various environmental surfaces. The use of a UV LED disinfection robot was effective in spacious areas such as an ICU, but its effects varied in small spaces like CTC rooms. These findings suggest that the UV LED robot may need enough space to disinfect rooms without recontamination by machine wheels or insufficient disinfection by shadowing.
We investigated potential nosocomial aerosol transmission of severe fever with thrombocytopenia syndrome virus (SFTSV) with droplet precautions. During aerosol generating procedures, SFTSV was be transmitted from person to person through aerosols. Thus, airborne precautions should be added to standard precautions to avoid direct contact and droplet transmission.
The aim of this study is to develop predictive models to predict organ at risk (OAR) complication level, classification of OAR dose-volume and combination of this function with our in-house developed treatment decision support system.
Materials and methods
We analysed the support vector machine and decision tree algorithm for predicting OAR complication level and toxicity in order to integrate this function into our in-house radiation treatment planning decision support system. A total of 12 TomoTherapyTM treatment plans for prostate cancer were established, and a hundred modelled plans were generated to analyse the toxicity prediction for bladder and rectum.
The toxicity prediction algorithm analysis showed 91·0% accuracy in the training process. A scatter plot for bladder and rectum was obtained by 100 modelled plans and classification result derived. OAR complication level was analysed and risk factor for 25% bladder and 50% rectum was detected by decision tree. Therefore, it was shown that complication prediction of patients using big data-based clinical information is possible.
We verified the accuracy of the tested algorithm using prostate cancer cases. Side effects can be minimised by applying this predictive modelling algorithm with the planning decision support system for patient-specific radiotherapy planning.
We examined the effects of various exercise intensities on recovery from middle cerebral artery occlusion (MCAO) in rats.
First, we administered a 120-minute left MCAO to male Sprague-Dawley rats and randomly assigned them to one of four groups: no exercise (Group 1), mild exercise (Group 2), moderate exercise (Group 3), and severe exercise (Group 4). Then, we trained the rats for 30 min per day for one week or two weeks. We used a five-point neurological evaluation scale to measure neurological deficits 1-day, 4-days, 7-days, 10-days and 14-days after MCAO and measured infarct volume by use of 2% 2,3,4-triphenyltetrazolium chloride in exercised brains. We also performed immunohistochemistry analysis of the brain to observe reactive astrocytosis at the peri-infarct region.
Neurological examination indicated that Group 2 and 3 recovered better than Group 1 after one week and two weeks (p<0.05). Moreover, Group 2 and 3 had reduced brain infarct volume compared with Group 1 after one week (p<0.05). There were no significant differences between Group 4 and Group 1. The thickness of the peri-infarct astrocytosis was significantly reduced in Group 4 relative to Group 1 after one week. There was a significant negative correlation between the extent of reactive astrocytosis and neurological recovery (r= -0.648, p<0.01).
This study demonstrates that mild to moderate exercise that begins soon after induced cerebral ischemia promotes recovery and that astrocytes may have an important role in the recovery process.
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 effects of polymer substrates on the interfacial structure and the thermal stability of Ga-doped ZnO (GZO) thin films were investigated. The GZO thin films were deposited on polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) substrates by rf-magnetron sputtering at room temperature, and thermal stability tests of the GZO thin films on the polymer substrates were performed at 150°C up to 8 h in air. Electrical and structural characterizations of the GZO thin films on the PET and the PEN substrates were carried out, and the origins of the stable interfacial structure and the improved thermal stability of the GZO thin film on the PEN substrate were discussed.
Maslinic acid is found in various natural sources, most notably in pomace olive oil, and exerts pro-apoptotic activities in various cancer cells in vitro. In the present study, DU145 human prostate cancer cells were cultured with 0–25 μm-maslinic acid to examine the effects of maslinic acid on the metastatic capacity of prostate cancer cells. Maslinic acid significantly (P <0·05) inhibited the basal and epidermal growth factor (EGF)-induced migration (27–64 %), invasion (23–60 %) and adhesion (8–40 %) of DU145 cells. Maslinic acid significantly (P <0·05) down-regulated both basal and EGF-stimulated secretion of matrix metalloproteinase (MMP)-9 (25–67 %), MMP-2 (50–86 %), urokinase-type plasminogen activator (uPA, about 100 %), vascular endothelial growth factor (VEGF, 98–100 %) and tissue inhibitors of metalloproteinases (TIMP)-1, as well as expression of uPA receptor (uPAR), intercellular adhesion molecules (22–33 %), vascular cell adhesion molecules (23–46 %) and E-cadherin, whereas it increased TIMP-2 secretion. Maslinic acid dramatically reduced the levels of hypoxia-inducible factor-1α (HIF-1α) protein and mRNA; the reduction was accompanied by reduced stability, nuclear levels and transcriptional activity of HIF-1α. The levels of phospho-Akt and phospho-extracellular signal-related kinase (ERK) were reduced in cells treated with maslinic acid, and the phosphoinositide 3-kinase inhibitor LY294002 and the mitogen-activated protein kinase kinase inhibitor PD98059 reduced HIF-1α levels and VEGF secretion. The results show that maslinic acid markedly inhibited the migration, invasion and adhesion of DU145 prostate cancer cells. Suppressing HIF-1α activation by inhibiting Akt and ERK activation may be part of the mechanism by which maslinic acid inhibited uPAR, E-cadherin, VEGF and MMP expression in DU145 cells.
The stability of organic thin film transistors (OTFTs) has become one of the most vital issues in this area of research. In this report, we investigated the stability of rubber stamp printed OTFTs. The electrical properties such as saturation field effect mobility, threshold voltage and on/off current ratio change significantly in ambient air condition. In order to analyze the degradation of the device, transistors were measured in vacuum, dry N2 and air environment as a function of time. In vacuum and dry N2 atmosphere, saturation field effect mobility and threshold voltage variations are relatively small compared to those measured in ambient condition.
To realize an air stable device, we applied a passivation layer which protects the device from oxygen or water molecules which is believed to be the source of the degradation. With the passivation layer, the threshold voltage shift was reduced suggesting that a proper passivation layer is a prerequisite in organic-based electronics.
Bonding process using indium-silver alloy which can withstand high temperature was investigated at relatively low temperature. We used a thermal evaporator and vacuum coater for making indium-silver contact. From the result of experiment, we observed that indium and silver films which have good quality are formed. From phase diagram of In-Ag alloy, we can find that melting point of these compounds increases with the silver content, i.e. eutectic (144° C) <AgIn2 (166° C) < (300° C) < (670° C) < (695° C). And these compounds are determined by the composition ratio of the source metal. Now we confirmed the thermal characteristics of Indium-Silver alloy is controlled by silver. Consequently we have developed Ag/In/Ag multi-layer composite which has higher melting point than that of normal contact. The melting point of Ag/In/Ag multi-layer is about 700° C. The joint cross-sections are studied using SEM(scanning electron microscopy) and EDX(Energy Dispersive X-rays). From these data, we observed that the composition and microstructure of Ag/In/Ag multi-layer were reliable and this bonding procedure is a better technique compared to the conventional structure of quantum well LED and GaN/Si LED structure was made by using sapphire for substrate and might be good for high temperature electronic devices in the future.
In this report, excimer laser annealed polycrystalline silicon (poly-Si) films on flexible polymer substrates are investigated. The amorphous silicon (a-Si) films were first deposited on polycarbonate (PC) and polyethersulfone (PES) substrates by radio-frequency (RF) magnetron sputter and sequentially annealed by XeCl excimer laser annealing system (λ = 308 nm). The argon concentration of a-Si films which was estimated by Rutherford Backscattering Spectrometry (RBS) was found to be dependent on the dynamic pressure during the deposition process and the sputtering gas. Typically, the argon concentration of a-Si film was 1 ∼ 2% when the film was deposited using argon gas at 6 mTorr. After the annealing process, the average grain size of the poly-Si film annealed with laser energy density of 289 mJ/cm2 was 400 nm estimated from transmission electron microscope (TEM) investigations.
High performance poly (3-hexylthiophene) (P3HT) thin film transistors (TFTs) array was fabricated on a polycarbonate substrate by micro-contact printing method. A thin polyimide layer (40 nm) was applied before silicon oxide deposition to improve the electrical properties of the TFT device. Also, the effects of O2 plasma treatment on the field effect mobility and output current behaviors of the devices were investigated. By plasma treatment, the surface roughness of gate dielectric was improved which accounts for the increased field effect mobility and the hole Schottky barrier height in electrode/semiconductor interface was lowered resulting in large drain current in the device. Based on the experiments, we fabricated P3HT TFTs array with 0.025 cm2/V·s in saturation field effect mobility and on/off current ratio of 103 ∼ 104 on a polycarbonate substrate.
Electrical and structural properties of indium-tin-oxide (ITO) films on flexible polymer substrates were investigated. Room temperature sputtered ITO films on polymer substrates are initially amorphous but become partially crystalline as oxygen partial pressure decreases under 1.5%. The crystallinity shows more (400) and (222) preferentially oriented textures as decreasing of oxygen pressure resulting in lower resistivity. Moreover, an interesting growth property similar to 3D growth mechanism including larger grain size and columnar-like grain structure was also observed. It is considered that the columnar-like grain structure is probably attributed to the poor surface morphology of polymer substrates Based on the experiments, we obtained high performance ITO films on a polycarbonate substrate including 3.8 × 10 –4 Ω-cm in resistivity and transmittance above 80% in the visible ranges at 0.2% oxygen partial pressure.
The Far-ultraviolet IMaging Spectrograph (FIMS) is a small spectrograph optimized for the observations of diffuse hot interstellar medium in far-ultraviolet wavebands (900–1150Å and 1335–1750Å). The instrument is expected to be sensitive to emission line fluxes an order of magnitude fainter than any previous missions. FIMS is currently under development and is scheduled for launch in 2002.
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