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This study aimed to investigate the diverse clinical manifestations and simple early biomarkers predicting mortality of COVID-19 patients admitted to the emergency department (ED). A total of 710 patients with COVID-19 were enrolled from 6,896 patients presenting to the ED between January 2022 and March 2022. During the study period, a total of 478 patients tested positive for COVID-19, among whom 222 (46.4%) presented with extrapulmonary manifestations of COVID-19; 49 (10.3%) patients displayed gastrointestinal manifestations, followed by neurological (n = 41; 8.6%) and cardiac manifestations (n = 31; 6.5%). In total, 54 (11.3%) patients died. A Cox proportional hazards model revealed that old age, acute kidney injury at presentation, increased total leukocyte counts, low platelet counts, decreased albumin levels, and increased LDH levels were the independent predictors of mortality. The albumin levels exhibited the highest area under the curve in receiver operating characteristic analysis, with a value of 0.860 (95% confidence interval, 0.796–0.875). The study showed the diverse clinical presentations and simple-to-measure prognostic markers in COVID-19 patients presenting to the ED. Serum albumin levels can serve as a novel and simple early biomarker to identify COVID-19 patients at high risk of death.
Although, attempts to apply virtual reality (VR) in mental healthcare are rapidly increasing, it is still unclear whether VR relaxation can reduce stress more than conventional biofeedback.
Methods:
Participants consisted of 83 healthy adult volunteers with high stress, which was defined as a score of 20 or more on the Perceived Stress Scale-10 (PSS-10). This study used an open, randomized, crossover design with baseline, stress, and relaxation phases. During the stress phase, participants experienced an intentionally generated shaking VR and serial-7 subtraction. For the relaxation phase, participants underwent a randomly assigned relaxation session on day 1 among VR relaxation and biofeedack, and the other type of relaxation session was applied on day 2. We compared the StateTrait Anxiety Inventory-X1 (STAI-X1), STAI-X2, the Numeric Rating Scale (NRS), and physiological parameters including heart rate variability (HRV) indexes in the stress and relaxation phases.
Results:
A total of 74 participants were included in the analyses. The median age of participants was 39 years, STAI-X1 was 47.27 (SD = 9.92), and NRS was 55.51 (SD = 24.48) at baseline. VR and biofeedback significantly decreased STAI-X1 and NRS from the stress phase to the relaxation phase, while the difference of effect between VR and biofeedback was not significant. However, there was a significant difference in electromyography, LF/HF ratio, LF total, and NN50 between VR relaxation and biofeedback
Conclusion:
VR relaxation was effective in reducing subjectively reported stress in individuals with high stress.
Mental illness among survivors of coronavirus disease 2019 (COVID-2019) during the post-illness period is an emerging and important health issue.
Aims
We aimed to investigate the prevalence of mental illness and the associated factors for its development among COVID-2019 survivors.
Method
From 1 January to 4 June 2020, data were extracted from the National Health Insurance Service COVID-19 database in South Korea. Patients with COVID-19 were defined as those whose test results indicated that they had contracted the infection, regardless of disease severity. COVID-19 survivors were defined as those who recovered from the infection. The primary end-point was the development of mental illness, which was evaluated between 1 January and 1 December 2020.
Results
A total 260 883 individuals were included in this study, and 2.36% (6148) were COVID-19 survivors. The COVID-19 survivors showed higher prevalence of mental illness than the control group (12.0% in the COVID-19 survivors v. 7.7% in the control group; odds ratio (OR) = 2.40, 95% CI 2.21–2.61, P < 0.001). Additionally, compared with the control group, the no specific treatment for COVID-19 group (OR = 2.23, 95% CI 2.03–2.45, P < 0.001) and specific treatment for COVID-19 group (OR = 3.27, 95% CI 2.77–3.87, P < 0.001) showed higher prevalence of mental illness among survivors.
Conclusions
In South Korea, COVID-19 survivors had a higher risk of developing mental illness compared with the rest of the populations. Moreover, this trend was more evident in COVID-19 survivors who experienced specific treatment in the hospital.
The National Institute of Neurological Disease and Stroke-Canadian Stroke Network (NINDS-CSN) 5-minute neuropsychology protocol consists of only verbal tasks, and is proposed as a brief screening method for vascular cognitive impairment. We evaluated its feasibility within two weeks after stroke and ability to predict the development of post-stroke dementia (PSD) at 3 months after stroke.
Method:
We prospectively enrolled subjects with ischemic stroke within seven days of symptom onset who were consecutively admitted to 12 university hospitals. Neuropsychological assessments using the NINDS-CSN 5-minute and 60-minute neuropsychology protocols were administered within two weeks and at 3 months after stroke onset, respectively. PSD was diagnosed with reference to the American Heart Association/American Stroke Association statement, requiring deficits in at least two cognitive domains.
Results:
Of 620 patients, 512 (82.6%) were feasible for the NINDS-CSN 5-minute protocol within two weeks after stroke. The incidence of PSD was 16.2% in 308 subjects who had completed follow-up at 3 months after stroke onset. The total score of the NINDS-CSN 5-minute protocol differed significantly between those with and without PSD (4.0 ± 2.7, 7.4 ± 2.7, respectively; p < 0.01). A cut-off value of 6/7 showed reasonable discriminative power (sensitivity 0.82, specificity 0.67, AUC 0.74). The NINDS-CSN 5-minute protocol score was a significant predictor for PSD (adjusted odds ratio 6.32, 95% CI 2.65–15.05).
Discussion:
The NINDS-CSN 5-minute protocol is feasible to evaluate cognitive functions in patients with acute ischemic stroke. It might be a useful screening method for early identification of high-risk groups for PSD.
To clarify the effect of bainite in microstructure on hydrogen diffusion and trapping behavior and susceptibility to hydrogen assisted cracking of API grade linepipe steel, three specimens with different fraction of bainite in the microstructure are used. Firstly, hydrogen diffusion and trapping behaviors of the steels are studied by utilizing the electrochemical permeation technique. For fundamental analysis on the experimental data, a variety of diffusion parameters were determined by curve-fitting with a theoretical diffusion equation based on numerical finite difference method (FDM). It indicates that the steel with higher fraction of bainite exhibits much higher sub-surface hydrogen concentration and much lower apparent hydrogen diffusivity. This behavior can be understood by the fact that the steel containing higher fraction of bainite in the microstructure has higher concentration of reversible traps and consequent larger diffusible hydrogen, leading to much slower diffusion kinetics of hydrogen atoms. Consequently, the susceptibility to hydrogen induced cracking (HIC) and sulfide stress cracking (SSC) of the steel with higher fraction of bainite increases significantly.
Feasibility of multiwavelength Raman spectroscopy was studied as a potentialin-line monitoring technique for grain size distribution in channel poly-Si usedin three dimensional stacked NAND (3D NAND) Flash memory devices. Variouschannel poly-Si materials in 3D-NAND Flash memory devices, converted fromchemical vapor deposition (CVD) grown a-Si, were characterized usingnon-contact, multiwavelength Raman spectroscopy and high resolutioncross-sectional transmission electron microscopy (HRXTEM). The Ramancharacterization results were compared with HRXTEM images. The correlationbetween the grain size distribution characterized by multiwavelength Ramanspectroscopy and “on current” (ION) of 3D NANDFlash memory devices was investigated. Good correlation between these techniqueswas seen. Multiwavelength Raman spectroscopy is very promising as anon-destructive in-line monitoring technique for grain size distribution inchannel poly-Si used in 3D NAND Flash memory devices.
During the past decade, carbapenemase-producing Enterobacteriaceae (CPE) has emerged and spread across the world.1 The major carbapenemase enzymes currently being reported are KPC, NDM-1, VIM, IMP, and OXA.2 Because carbapenemase can be effectively transmitted via mobile genetic elements, and current therapeutic options for CPE infections are extremely limited, CPE may be one of the most serious contemporary threats to public health. However, very little is known about the characteristics of CPE carriage during hospitalization. The aims of this study were to investigate the clearance rate of CPE carriage and determine the number of consecutive negative cultures required to confirm CPE clearance. We also examined CPE transmission among hospitalized patients.
Infect. Control Hosp. Epidemiol. 2015;36(11):1361–1362
Uremia is a syndrome of clinical and metabolic abnormalities, which develops in parallel with the deterioration of renal function. Uremic encephalopathy is one of many manifestations of acute or chronic renal failure. It is usually applied to patients with cortical involvement, such as confusion, seizure, tremor, myoclonus, or asterixis. Some cases of acute extrapyramidal movement disorders associated with bilateral basal ganglia lesions, especially parkinsonism have been reported in uremic patients. Here, we report a diabetic uremic patient who developed acute chorea associated with bilateral basal ganglia lesions.
Genetic variation in wild soybean (Glycine soja Sieb. and Zucc.) is a valuable resource for crop improvement efforts. Soybean is believed to have originated from China, Korea, and Japan, but little is known about the diversity or evolution of Korean wild soybean. Therefore, in this study, we evaluated the genetic diversity and population structure of 733 G. soja accessions collected in Korea using 21 simple sequence repeat (SSR) markers. The SSR loci produced 539 alleles (25.7 per locus) with a mean genetic diversity of 0.882 in these accessions. Rare alleles, those with a frequency of less than 5%, represented 75% of the total number. This collection was divided into two populations based on the principal coordinate analysis. Accessions from population 1 were distributed throughout the country, whereas most of the accessions from population 2 were distributed on the western side of the Taebaek and Sobaek mountains. The Korean G. soja collection evaluated in this study should provide useful background information for allele mining approach and breeding programmes to introgress alleles into the cultivated soybean (G. max (L). Merr.) from wild soybean.
Although there are rapidly growing concerns about the high rates of cognitive dysfunction in Korea, the knowledge of risk factors for Alzheimer’s disease (AD) among the general public in Korea remains to be elucidated.
Methods:
A total of 2767 randomly selected subjects from the Ansan Geriatric Study were questioned on their knowledge of putative risk factors for AD. Their answers were compared with their sociodemographic data and other variables.
Results:
The most common stated risk factor was being older (59.6%), followed by head trauma (33.6%) and cerebrovascular disease (30.4%). However, a substandard education, which is a known risk factor, was considered significant by only 9.5% of the subjects. Predictors for a worse knowledge of the risk factors for AD were being older, a lower level of education, lower economic status and the attitude that dementia is not curable.
Conclusion:
This study revealed that misunderstanding about AD is more prevalent in older subjects and those with a lower level of education, and so public health education on the basic concepts of AD should be targeted at this population.
The formation and morphological evolution of germanides formed in a ternary Ni/Ta-interlayer/Ge system were examined by ex situ and in situ annealing experiments. The Ni germanide film formed in the Ni/Ta-interlayer/Ge system maintained continuity up to 550°C, whereas agglomeration of the Ni germanide occurred in the Ni/Ge system without Ta-interlayer. Through microstructural and chemical analysis of the Ni/Ta-interlayer/Ge system during and after in situ annealing in a transmission electron microscope, it was confirmed that the Ta atoms remained uniformly on the top of the newly formed Ni germanide layer during the diffusion reaction. Consequently, the agglomeration of the Ni germanide film was retarded and the thermal stability was improved by the Ta incorporation.
The oxidation mechanism and thermal stability of nickel oxide (NiO)/carbon nanotube (CNT) composites were investigated by examining composites with different NiO contents by thermogravimetric analysis and transmission electron microscopy (TEM). NiO acts as a catalyst in the oxidation of CNT in the composite. CNTs can be oxidized, even in a vacuum, by reducing NiO to nickel at temperatures lower than the normal oxidation temperature of CNTs. This phase transition was confirmed directly by in situ heating TEM observations. In air, reduction by CNT occurs simultaneously with reoxidation by gaseous O2 molecules, and NiO maintains its phase. The thermal stability decreased with increasing NiO content because of defects in the CNT generated by the NiO loading.
Using immunostaining methodology, we traced the axonal projection of FMRFamide (Phe-Met-Arg-Phe-NH2)-like immunoreactive (LI) medial neurosecretory cells (MNCs) and lateral neurosecretory cells (LNCs) from the brain into the ventral nerve cord (VNC) and retrocerebral complex in Bombyx mori (L.) (Lepidoptera: Bombycidae). Of the seven pairs of FMRFamide-LI MNCs, one pair extended its axons from the brain pars intercerebralis into the VNC ipsilateral connective where they appeared to terminate. The axons of the remaining MNCs ran through decussation in the brain median region and contralateral nervi corporis cardiaci (NCC) I out of the brain, and eventually innervated the contralateral corpus cardiacum (CC). Axons from the single pair of FMRFamide-LI LNCs projected into the ipsilateral NCC II fused with NCC I without decussation in the brain, and finally terminated in the CC. These results suggest that transport of the FMRFamide-like neuropeptide from may be related to the modulation of functions such as gut contraction in MNCs terminating in the VNC, and regulation of production and/or secretion of specific hormones such as juvenile hormone in MNCs and LNCs terminating in the CC.
Oxidative stress may be affected by lead exposure as well as antioxidants, yet little is known about the interaction between dietary antioxidants and blood lead levels (BLL) on oxidative stress level. We investigated the interaction between dietary antioxidants and BLL on oxidative stress level. As part of the Biomarker Monitoring for Environmental Health conducted in Seoul and Incheon, Korea, between April and December 2005, we analysed data from 683 adults (female = 47·4 %, mean age 51·4 (sd 8·4) years) who had complete measures on BLL, dietary intakes and oxidative stress marker (urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG)). Dietary intakes were assessed by a validated semi-quantitative FFQ, BLL was measured using atomic absorption spectrophotometry, and 8-OHdG by ELISA. Multivariate linear regression analyses were used to evaluate the influence of BLL on the association between dietary antioxidants and 8-OHdG. Geometric means of BLL and 8-OHdG concentrations were 4·1 (sd 1·5) μg/dl and 5·4 (sd 1·9) μg/g creatinine, respectively. Increases of vitamins C and E were significantly associated with the decrease of log10 8-OHdG in the adults from the lowest quartile of the BLL group ( ≤ 3·18 μg/dl, geometric mean = 2·36 μg/dl) than those of the highest quartile BLL group (>5·36 μg/dl, geometric mean = 6·78 μg/dl). Regarding antioxidant-related foods, vegetables excluding kimchi showed a higher inverse relationship with 8-OHdG in the lowest quartile BLL group than the highest group. These findings suggest a rationale for lowering the BLL and increasing the intake of dietary antioxidants in the urban population in Korea.
The size dependence of the lattice parameter of nanosolids has extensively been studied because lattice strain engineering is important in controlling the physical properties of nanowires (NWs), such as band gap, carrier transport, mechanical strength, etc. We have investigated the size-dependent lattice behavior of microstructure-controlled Sn NWs with radii of 7–35 nm. The NW microstructures were controlled as single-crystal, granular, and bamboo structures in the longitudinal direction. Results showed that the a-axis lattice parameter in the [100]-longitudinal direction of NWs can be controlled within 1% by varying the wire microstructure for the same wire radius because it is strongly dependent on the microstructure and the wire radius. Moreover, as the randomness of the grain orientation in the microstructure-controlled NWs increases, by which the anisotropy of surface stress is effectively reduced, the lattice strain of the NW can be compressive or tensile as a function of the wire radius. The longitudinal lattice parameters of microstructure-controlled Sn NWs can be tailored by reducing the effective anisotropy of surface stresses under a dimension confinement in the nanometer scale.
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.
The objectives of this study were to evaluate fish guild compositions and national river health using a multi-metric model of the Korean index of biological integrity using fishes (K-IBIF) in four major Korean watersheds along with water chemistry and habitat quality. Tolerant and omnivore fish species dominated all the watersheds, and the proportions of tolerance guilds and trophic guilds reflected water chemistry and habitat quality. The number of sensitive species and insectivore species had negative correlations (r < −0.42, P < 0.01) with chemical water quality (biological oxygen demand (BOD)), while tolerant species and omnivore species had positive correlation (r > 0.27, P < 0.05) with BOD values. Physical habit conditions, based on qualitative habitat evaluation index (QHEI) model, indicated a “good” condition (mean = 68.9; range = 45–105) in three watersheds, except for the Yeongsan River watershed. Values of QHEI were significantly correlated (R2 > 0.4, P < 0.01) with nitrogen and phosphorus levels in all watersheds, suggesting that habitat degradation is associated with eutrophication. Model values of K-IBIF in the watersheds averaged 18.2, indicating a “fair” condition, and about 37% of all observations in K-IBIF model values were judged as a “poor” health condition, indicating severe health impairment. Overall, our data suggest that degradation of the river health was due to a combined effect of chemical pollution and physical habitat modifications. This research provides valuable information on Korean river conservation and restoration in the future.
Stream development can generate environmental changes that impact fish communities. In temperate streams, the distribution of fish species is associated with environmental gradients. To analyze the relevant factors, large-scale exploration is required. Thus, to evaluate the distribution patterns of fish in Korea, sampling was conducted on a national scale at 720 sites over a 6-week period in 2009. A total of 124 fish species in 27 families were identified; Zacco platypus and Zacco koreanus of the Cyprinidae were the dominant and subdominant species, respectively. Of the species found, 46 (37.1%) were endemic and 4 (3.2%) exotic; of the latter, Micropterus salmoides and Lepomis macrochirus were widely distributed. Upon canonical correspondence analysis (CCA), both altitude and biological oxygen demand (BOD) were highly correlated with CCA axes 1 and 2, respectively. This explained 62.5% of the species–environment relationship. Altitude and stream order were longitudinally related to species distribution. The numbers of both total and endemic species gradually increased as streams grew in size to the fourth–fifth-order, and decreased in sixth-order, streams. Overall, fish communities were stable throughout the entire watershed, whereas some species showed site-specific occurrence patterns due to the paleogeomorphological characteristics of Korean peninsula. However, various anthropogenic activities may negatively affect fish communities. Therefore, both short- and long-term sustainable management strategies are required to conserve native fish fauna.