To clarify transmissibility of the severe acute respiratory syndrome coronavirus 2 Omicron variant, we determined serial intervals and secondary attack rates among household contacts in South Korea. ...Mean serial interval for 12 transmission pairs was 2.9 days, and secondary attack rate among 25 households was 50.0%, raising concern about a rapid surge in cases.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Chalcogenide material Ge2Sb2Te5 (GST) has bistable phases, the so‐called amorphous and crystalline phases that exhibit large refractive index contrast. It can be reversibly switched within a ...nanosecond time scale through applying thermal bias, especially optical or electrical pulse signals. Recently, GST has been exploited as an ingredient of all‐optical dynamic metasurfaces, thanks to its ultrafast and efficient switching functionality. However, most of these devices provide only two‐level switching functionality and this limitation hinders their application to diverse all‐optical systems. In this paper, the method to expand switching functionality of GST metasurfaces to three level through engineering thermo‐optically creatable hybrid state that is co‐existing state of amorphous and crystalline GST‐based meta‐atoms is proposed. Furthermore, the novel hologram technique is introduced for providing the visual information that is only recognizable in the hybrid state GST metasurface. Thanks to thermo‐optical complexity to make the hybrid state, the metasurface allows the realization of highly secured visual cryptography architecture without the complex optical setup. The phase‐change metasurface based on multi‐physical design has significant potential for applications such as all‐optical image encryption, security, and anti‐counterfeiting.
Here, the method to create the hybrid state Ge2Sb2Te5 metasurface is introduced and applied to all‐optical cryptography. Based on the optical–thermal analysis and hologram optimization process, the well‐protected visual text is included in the hybrid state metasurface. The all‐optical cryptography system dramatically improves security level while providing ultrafast operation speed without a complex optical setup.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
As the coronavirus disease 2019 (COVID‐19) pandemic continues, reinfection is likely to become increasingly common. However, confirming COVID‐19 reinfection is difficult because it requires ...whole‐genome sequencing of both infections to identify the degrees of genetic differences. Since the first reported case of reinfection of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in the Republic of Korea in April 2020, four additional cases were classified as suspected reinfection cases. We performed whole‐genome sequencing of viral RNA extracted from swabs obtained at the initial infection and reinfection stages of these four suspected cases. The interval between initial infection and reinfection of all four suspected cases was more than 3 months. All four patients were young (10–29 years), and they displayed mild symptoms or were asymptomatic during the initial infection and reinfection episodes. The analysis of genome sequences combined with the epidemiological results revealed that only two of the four cases were confirmed as reinfection, and both were reinfected with the Epsilon variant. Due to the prolonged COVID‐19 pandemic, the possibility of reinfections with SARS‐CoV‐2 variants is increasing, as reported in our study. Therefore, continuous monitoring of cases is necessary.
Highlights
We investigated four suspected SARS‐CoV‐2 reinfection cases in Korea.
We performed whole genome sequencing of initial and reinfection samples.
Two of the four suspected cases were confirmed as reinfection cases.
The Epsilon variant was detected in the reinfected patients.
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Exploiting spin transport increases the functionality of electronic devices and enables such devices to overcome physical limitations related to speed and power. Utilizing the Rashba effect at the ...interface of heterostructures provides promising opportunities toward the development of high‐performance devices because it enables electrical control of the spin information. Herein, the focus is mainly on progress related to the two most compelling devices that exploit the Rashba effect: spin transistors and spin–orbit torque devices. For spin field‐effect transistors, the gate‐voltage manipulation of the Rashba effect and subsequent control of the spin precession are discussed, including for all‐electric spin field‐effect transistors. For spin–orbit torque devices, recent theories and experiments on interface‐generated spin current are discussed. The future directions of manipulating the Rashba effect to realize fully integrated spin logic and memory devices are also discussed.
The Rashba effect provides fascinating functionality for electronic devices because of the electric modulation of spin orientation. Semiconductor spin transistors and spin–orbit torque devices are reviewed. Recent theories and experiments related to generating and controlling spin current are presented. Future directions in the development of spin logic and memory devices are also discussed.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Approximately 40% of new chemical entities (NCEs), including anticancer drugs, have been reported as poorly water-soluble compounds. Anticancer drugs are classified into biologic drugs (monoclonal ...antibodies) and small molecule drugs (nonbiologic anticancer drugs) based on effectiveness and safety profile. Biologic drugs are administered by intravenous (IV) injection due to their large molecular weight, while small molecule drugs are preferentially administered by gastrointestinal route. Even though IV injection is the fastest route of administration and ensures complete bioavailability, this route of administration causes patient inconvenience to visit a hospital for anticancer treatments. In addition, IV administration can cause several side effects such as severe hypersensitivity, myelosuppression, neutropenia, and neurotoxicity. Oral administration is the preferred route for drug delivery due to several advantages such as low cost, pain avoidance, and safety. The main problem of NCEs is a limited aqueous solubility, resulting in poor absorption and low bioavailability. Therefore, improving oral bioavailability of poorly water-soluble drugs is a great challenge in the development of pharmaceutical dosage forms. Several methods such as solid dispersion, complexation, lipid-based systems, micronization, nanonization, and co-crystals were developed to improve the solubility of hydrophobic drugs. Recently, solid dispersion is one of the most widely used and successful techniques in formulation development. This review mainly discusses classification, methods for preparation of solid dispersions, and use of solid dispersion for improving solubility of poorly soluble anticancer drugs.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
DNA Damage and Repair in Eye Diseases Sohn, Joanna; Lee, Sang-Eun; Shim, Eun-Yong
International journal of molecular sciences,
02/2023, Volume:
24, Issue:
4
Journal Article
Peer reviewed
Open access
Vision is vital for daily activities, and yet the most common eye diseases-cataracts, DR, ARMD, and glaucoma-lead to blindness in aging eyes. Cataract surgery is one of the most frequently performed ...surgeries, and the outcome is typically excellent if there is no concomitant pathology present in the visual pathway. In contrast, patients with DR, ARMD and glaucoma often develop significant visual impairment. These often-multifactorial eye problems can have genetic and hereditary components, with recent data supporting the role of DNA damage and repair as significant pathogenic factors. In this article, we discuss the role of DNA damage and the repair deficit in the development of DR, ARMD and glaucoma.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In November 2021, 14 international travel-related severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 (omicron) variant of concern (VOC) patients were detected in South Korea. ...Epidemiologic investigation revealed community transmission of the omicron VOC. A total of 80 SARS-CoV-2 omicron VOC-positive patients were identified until December 10, 2021 and 66 of them reported no relation to the international travel. There may be more transmissions with this VOC in Korea than reported.
The flipped classroom has become a popular pedagogical approach in higher education with its capability to promote students' active engagement in higher-order tasks; nevertheless, studies have shown ...that the flipped classroom is not always successful. The purpose of this study was to investigate factors including student characteristics as well as learning and teaching factors that influence students' affective and motivational outcomes in flipped classrooms in higher education. A total of 350 university students in 12 different flipped classrooms completed survey instruments at the end of the semester that assessed their experience with flipped classrooms, emotional experiences, and motivation. Results indicated that enjoyment was predicted by the perception of preview materials, teacher facilitation, and participation in learning activities. Boredom was predicted by the perception of preview materials and participation in learning activities. Self-efficacy was significantly explained by both student characteristics and learning and teaching factors. Further discussion and implications are provided.
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BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Clusters of tightly packed synaptic vesicles (SVs) are a defining feature of nerve terminals. While SVs are mobile within the clusters, the clusters have no boundaries consistent with a liquid phase. ...We previously found that purified synapsin, a peripheral SV protein, can assemble into liquid condensates and trap liposomes into them. How this finding relates to the physiological formation of SV clusters in living cells remains unclear. Here, we report that synapsin alone, when expressed in fibroblasts, has a diffuse cytosolic distribution. However, when expressed together with synaptophysin, an integral SV membrane protein previously shown to be localized on small synaptic-like microvesicles when expressed in non-neuronal cells, is sufficient to organize such vesicles in clusters highly reminiscent of SV clusters and with liquid-like properties. This minimal reconstitution system can be a powerful model to gain mechanistic insight into the assembly of structures which are of fundamental importance in synaptic transmission.
Spin-orbit torques arising from the spin-orbit coupling of non-magnetic heavy metals allow electrical switching of perpendicular magnetization. However, the switching is not purely electrical in ...laterally homogeneous structures. An extra in-plane magnetic field is indeed required to achieve deterministic switching, and this is detrimental for device applications. On the other hand, if antiferromagnets can generate spin-orbit torques, they may enable all-electrical deterministic switching because the desired magnetic field may be replaced by their exchange bias. Here we report sizeable spin-orbit torques in IrMn/CoFeB/MgO structures. The antiferromagnetic IrMn layer also supplies an in-plane exchange bias field, which enables all-electrical deterministic switching of perpendicular magnetization without any assistance from an external magnetic field. Together with sizeable spin-orbit torques, these features make antiferromagnets a promising candidate for future spintronic devices. We also show that the signs of the spin-orbit torques in various IrMn-based structures cannot be explained by existing theories and thus significant theoretical progress is required.
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IJS, NUK, SBMB, UL, UM, UPUK
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