Since mid-December of 2019, coronavirus disease 2019 (COVID-19) has been spreading from Wuhan, China. The confirmed COVID-19 patients in South Korea are those who came from or visited China. As ...secondary transmissions have occurred and the speed of transmission is accelerating, there are rising concerns about community infections. The 54-year old male is the third patient diagnosed with COVID-19 in Korea. He is a worker for a clothing business and had mild respiratory symptoms and intermittent fever in the beginning of hospitalization, and pneumonia symptoms on chest computerized tomography scan on day 6 of admission. This patient caused one case of secondary transmission and three cases of tertiary transmission. Hereby, we report the clinical findings of the index patient who was the first to cause tertiary transmission outside China. Interestingly, after lopinavir/ritonavir (Kaletra, AbbVie) was administered, β-coronavirus viral loads significantly decreased and no or little coronavirus titers were observed.
High-performance metal-oxide thin-film transistors (oxide-TFTs) with high-k zirconium dioxide (ZrO2) dielectric and indium-gallium-zinc oxide (IGZO) semiconducting films were developed on flexible ...polyimide substrates. The flexible IGZO-TFTs fabricated using a simple and effective sol-gel-based solution-process combined with oxygen-enriched consecutive annealing at 200 °C, exhibited a high field-effect mobility of 13.6 cm2 V−1 s−1 at 5 V, on/off ratio of 1.05 × 106, gate leakage current of 2.7 × 10−11 A, and threshold voltage of 0.44 V. The effects of O2 annealing on the film quality of the sol-gel-based ZrO2 and IGZO were investigated by analyzing the crystallinity, morphology, and degree of metal-oxygen bonding states. Temperature-dependent steady-state direct-current measurements over the temperature range of 90–300 K, and time-domain non-quasi-static transient measurements with a minimized resistance-capacitance time constant were performed. Thus, the activation energy, density of states, interface trap density, and velocity distribution were determined to investigate the charge transport mechanism responsible for the high performance of the oxide- TFTs proposed in this study. An enhancement-load-type N-channel metal-oxide semiconductor (NMOS) inverter consisting of two oxide-TFTs fabricated via O2 annealing was demonstrated. The flexible NMOS inverter exhibited a high gain of 10.8 at 5 V and outstanding mechanical stability against 10,000 cycles of bending stresses at a strain of 30% without a passivation or buffer film.
Sol-gel-based metal-oxide TFTs fabricated by oxygen annealing at low temperatures and their applications in high-performance flexible NMOS inverters were developed. Display omitted
●Flexible oxide TFTs with sol-gel-based metal-oxide films fabricated by O2 annealing at low temperatures was developed.●Activation energy, density of states, and velocity distribution were obtained for high performance oxide TFTs.●Flexible NMOS inverter exhibiting high inverting performance and mechanical stability was realized.
Although detecting small objects is critical in various applications, neural network models designed and trained for generic object detection struggle to do so with precision. For example, the ...popular Single Shot MultiBox Detector (SSD) tends to perform poorly for small objects, and balancing the performance of SSD across different sized objects remains challenging. In this study, we argue that the current IoU-based matching strategy used in SSD reduces the training efficiency for small objects due to improper matches between default boxes and ground truth objects. To address this issue and improve the performance of SSD in detecting small objects, we propose a new matching strategy called aligned matching that considers aspect ratios and center-point distance in addition to IoU. The results of experiments on the TT100K and Pascal VOC datasets show that SSD with aligned matching detected small objects significantly better without sacrificing performance on large objects or requiring extra parameters.
In this article we present CodeCast, a network-coding-based ad hoc multicast protocol. CodeCast is especially well-suited for multimedia applications with low-loss, low-latency constraints such as ...audio/video streaming. The key ingredient of CodeCast is random network coding, which transparently implements both localized loss recovery and path diversity with very low overhead. Simulation results show that in a typical setting, CodeCast yields a nearly 100 percent delivery ratio, as compared to a 94 percent delivery ratio by traditional multicast. More importantly, the overhead is reduced by as much as 50 percent
Navigation of nanoparticles to target sites of blood flow disturbance markedly upgrades the diagnostic paradigm in vascular medicine. The theranostic treatment of pre‐stenotic vessels can prevent the ...irreversible occlusion process effectively. Here, these nanotheranostic functions are established by displaying CDK9(cyclin‐dependent kinase 9)‐targeting peptide (P.) onto nanovesicles (NV) and liposomes using the navigation function and subsequent binding‐on signaling of P. as a game‐changer. When rabbit vessels are allografted with injecting contrast‐loaded P. liposomes, the case‐dependent stenotic degree after 2–6 weeks can be diagnosed accurately within 2–4 days via computed tomography imaging with cross‐validation in a mouse model of partial carotid ligation. Furthermore, the anti‐CDK9 signaling of P. NV is activated post‐targeting and effectively prevents vascular stenosis by suppressing inflammation and lipotoxicity in the vessels, serum, and/or liver. CDK9 targeting is confirmed using computer, in vitro, and in vivo models. This study demonstrates an unprecedented nanotheranostic function for future clinical applications.
The disturbed flow‐sensing peptide plays a game‐changer role in guiding diagnosis and treatment of pre‐stenotic vessels as a theranostic navigator. Displaying the peptide on nanoparticles enables accurate prediction of vascular stenosis with subsequent prevention of vascular remodeling through multi‐organ targeting. The results from rabbit, mouse, and in vitro models validates an unprecedented nanotheranostic function for the future medicine.
Wet-chemical etching of the barrier oxide layer of anodic aluminum oxide (AAO) was systematically investigated by using scanning electron microscopy (SEM), secondary ion mass spectrometry (SIMS), and ...a newly devised experimental setup that allows accurate in situ determination of the pore opening point during chemical etching of the barrier oxide layer. We found that opening of the barrier oxide layer by wet-chemical etching can be significantly influenced by anodization time (t anodi). According to secondary ion mass spectrometry (SIMS) analysis, porous anodic aluminum oxide (AAO) samples formed by long-term anodization contained a lower level of anionic impurity in the barrier oxide layer compared to the short-term anodized one and consequently exhibited retarded opening of the barrier oxide layer during the wet-chemical etching. The observed compositional dependence on the anodization time (t anodi) in the barrier oxide layer is attributed to the progressive decrease of the electrolyte concentration upon anodization. The etching rate of the outer pore wall at the bottom part is lower than that of the one at the top part due to the lower level of impurity content in that region. This indicates that a concentration gradient of anionic impurity in the outer pore wall oxide may be established along both the vertical and radial directions of cylindrical pores. Apart from the effect of electrolyte concentration on the chemical composition of the barrier oxide layer, significantly decreased current density arising from the lowered concentration of electrolyte during the long-term anodization (∼120 h) was found to cause disordering of pores. The results of the present work are expected to provide viable information not only for practical applications of nanoporous AAO in nanotechnology but also for thorough understanding of the self-organized formation of oxide nanopores during anodization.
Glutathione (GSH) is a thiol that plays a significant role in nutrient metabolism, antioxidant defense and the regulation of cellular events. GSH deficiency is related to variety of diseases, so it ...is useful to develop novel approaches for GSH evaluation and detection. In this study we used nitrogen and phosphorus co-doped carbon dot-gold nanoparticle (NPCD-AuNP) composites to fabricate a simple and selective fluorescence sensor for GSH detection. We employed the reductant potential of the nitrogen and phosphorus co-doped carbon dots (NPCDs) themselves to form AuNPs, and subsequently NPCD-AuNP composites from Au
. The composites were characterized by using a range of spectroscopic and electron microscopic techniques, including electrophoretic light scattering and X-ray diffraction. The overlap of the fluorescence emission spectrum of NPCDs and the absorption spectrum of AuNPs resulted in an effective inner filter effect (IFE) in the composite material, leading to a quenching of the fluorescence intensity. In the presence of GSH, the fluorescence intensity of the composite was recovered, which increased proportionally to increasing the GSH concentration. In addition, our GSH sensing method showed good selectivity and sensing potential in human serum with a limit of detection of 0.1 µM and acceptable results.
Metabolic syndrome (MetS) is considered very important because of the increased risk for cardiovascular diseases. Identifying modifiable factors may help prevent MetS. We aimed to investigate the ...relationship between iodine intake as a dietary factor and MetS in euthyroid adult in an iodine-replete area. A total of 4,277 adult aged ≥19 years from the Korea National Health and Nutrition Examination Survey VI (2013–2015) with urinary iodine concentration (UIC) results and normal thyroid function were included. Participants were grouped according to their iodine nutrition status based on the WHO recommendations and modifications: insufficient (<100 μg/L), adequate (100–299 μg/L), and excessive (≥300 μg/L) iodine intake. We estimated the odds ratios (ORs) for MetS according to the UIC groups using logistic regression models. Of the study participants, 27.2% men and 23.9% women had MetS. Men with excessive iodine intake had a significantly lower risk of elevated triglycerides OR 0.733, 95% confidence interval (CI) 0.603–0.890, p = 0.010, as compared to those with adequate iodine intake. Women with insufficient iodine intake had a significantly greater risk of elevated blood glucose (OR 1.519, 95% CI 1.011–2.282, p = 0.044), as compared to those with adequate iodine intake. In women, insufficient iodine intake was a significant risk factor for MetS compared to adequate iodine intake, even after adjusting for confounding variables including age, smoking, alcohol consumption, walking activity, serum thyroid-stimulating hormone, free thyroxine, and anti-thyroid peroxidase antibody (OR 1.544, 95% CI 1.031–2.311, p = 0.035). There was no association between iodine intake and risk of MetS in men. In conclusion, insufficient iodine intake was associated with an increased risk of MetS only in euthyroid adult women. Our data support that sex differences may influence the relationship between iodine intake as a dietary pattern and MetS.