In this article, we present a 4.13-GHz ultrahigh-speed (UHS) pseudo two-port SRAM for high-performance computing (HPC) in 4-nm FinFET technology. By applying the bitline (BL) charge time reduction ...(BLCTR) with clamped BL discharge (CBLD) scheme that improves BL charge and write time, the flying word-line (WL) architecture that enhances WL enable time, and the dual address pumping (DAP) architecture with flip-flop that reduces read and write switching time and address latching time, the proposed pseudo two-port SRAM demonstrates a UHS performance with a 4.13-GHz operating speed. A test-chip using the proposed scheme and architecture is fabricated in Samsung 4 nm FinFET technology and demonstrates UHS pseudo two-port 32-Kb SRAM operating at 4.13 GHz under 0.85 V and 100 c conditions.
In Korea, decommissioning of nuclear power plants and transportation of the decommissioning waste are expected to expand in the near future. It is necessary to confirm that radiological risks to the ...public and workers are not significant through radiological safety assessment. The objective of this study is to assess the radiological safety for transportation of RPV waste, which is a major decommissioning waste with relatively high level of radioactivity. It was assumed that the waste would be transported to the Gyeongju disposal facility by land transportation. First, the source term and transportation method of the RPV waste were determined, and the external dose rates from the waste were calculated using MCNP. Then, transportation scenarios were assumed under both normal and accident conditions. Under the scenarios, radiation doses were calculated using the RADTRAN. Under normal operation scenarios without a transportation accident, assuming 40 shipments per year, the average individual doses for the public ranged from 6.56×10
to 2.18×10
mSv yr
. The maximum individual doses for only a single shipment ranged from 2.43×10
to 3.14×10
mSv. For cargo handlers and vehicle crew members, the average doses were 2.26×10
mSv yr
and 2.95 mSv yr
, respectively. Under transportation accident scenarios, average individual radiological risks which are product of the radiation doses and the annual accident rates ranged from 1.14×10
to 1.61×10
mSv yr
by transportation route segment when considering the transportation accident rate. Average individual doses assuming transportation accident occurrence ranged from 2.62×10
to 1.42×10
mSv. The maximum individual dose under accident conditions was 7.99×10
mSv. The calculated doses were below the regulatory limits in Korea. However, relatively high doses were observed for cargo handlers and vehicle crew members because of conservative assumptions. This study results can be used as basic data for the radiological safety assessment for the decommissioning waste transportation in the future.
Computational fluid dynamics simulations of fibrous filters with 56 combinations of different fiber sizes, packing densities, face velocities, and thicknesses were conducted for developing models ...that predict pressure drops across nanofiber filters. The accuracy of the simulation method was confirmed by comparing the numerical pressure drops to the experimental data obtained for polyacrylonitrile electrospun nanofiber filters. In the simulations, an aerodynamic slip effect around the surface of the small nanofibers was considered. The results showed that, unlike in the case of conventional filtration theory, pressure drops across the thin layers of electrospun nanofiber filters are not proportional to the thickness. This might be a critical factor for obtaining precise pressure drops across the electrospun nanofiber filters with extremely thin layers. Finally, we derived the product of drag coefficient and Reynolds number as a function of packing density, Knudsen number, and ratio of thickness to fiber diameter to get the correlation equation for pressure drop prediction. The obtained equation predicted the pressure drops across the nanofiber filters with the maximum relative difference of less than 15%.
Purpose
This study aims to integrate reviewers’ and readers’ discrepant perspectives on extremely negative reviews. Specifically, this study examines the relationship between negative emotion ...intensity levels and reviews helpfulness on two platforms: integrated websites and social networking sites (SNS) to emphasize the role of platform types on customers’ purchase decisions.
Design/methodology/approach
This research adopts a mixed-method approach of business intelligence approach and quasi-experimental design. Study 1 performed text mining and Welch’s t-test to compare reviewers’ negative emotion intensity levels on two platforms. Study 2 adopted a 2*2 factorial quasi-experimental design to examine how intense negative emotions impact the perceived reviews helpfulness on two platforms. A 3*2 factorial design in Study 3 also tested social tie strength’s moderating effect between the intensity of negative emotions and review helpfulness.
Findings
The current study reveals that integrated website reviewers tend to express more extreme negative emotions than SNS reviewers. SNS and integrated website readers deem reviews that embed severe negative emotions as less helpful. The moderating role of social tie strength between extremely negative emotions on review helpfulness was insignificant in the study.
Research limitations/implications
This study enriches the online review literature by comparing writers’ and readers’ perspectives on online reviews with extremely negative emotions across two online platform types: integrated websites and SNS. From the writers’ perspective, this study highlights anonymity and the presence of an audience as essential factors that reviewers consider in selecting an online review platform to express themselves. This research also sheds light on how readers’ perspectives on extremely negative reviews conflict with the presumptions of writers of extremely negative reviews on integrated websites by demonstrating that content embedding extremely negative emotions is less helpful regardless of platform type.
Practical implications
This research provides online negative review management strategies to platform and hotel managers. The findings suggest hotel and review platform managers should consider adopting review alignment or monitoring systems based on negative emotions intensity levels since readers on both platforms perceive reviews embedding extremely negative emotions as less helpful. Additionally, hotel managers can progress promotions to guests who share online reviews on SNS since SNS reviewers are more likely to attenuate their extremely negative emotions when writing reviews.
Originality/value
This research innovatively provides a comprehensive overview of negative reviews’ production and consumption process from reviewers’ and readers’ perspectives. This research also provides practitioners insight into the nature of two different platform types and the management of negative reviews on these platforms.
Substituted
-phenyl cinnamamide derivatives were designed and synthesized to confirm activation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway by the electronic effect on beta-position ...of Michael acceptor according to introducing the R
and R
group. Compounds were screened using the Nrf2/antioxidant response element (ARE)-driven luciferase reporter assay. Compound
showed desirable luciferase activity in HepG2 cells without cell toxicity. mRNA and protein expression of Nrf2/ARE target genes such as NAD(P)H quinone oxidoreductase 1, hemeoxygenase-1, and glutamate-cysteine ligase catalytic subunit (GCLC) were upregulated by compound
in a concentration-dependent manner. Treatment with
resulted in increased endogenous antioxidant glutathione, showing strong correlation with enhanced GCLC expression for synthesis of glutathione. In addition,
-butyl hydroperoxide (
-BHP)-generated reactive oxygen species were significantly removed by
, and the results of a cell survival assay in a
-BHP-induced oxidative cell injury model showed a cytoprotective effect of
in a concentration dependent manner. In conclusion, the novel compound
can be utilized as an Nrf2/ARE activator in antioxidative therapy.
We assessed the safety and immunogenicity of two recombinant DNA vaccines for COVID-19: GX-19 containing plasmid DNA encoding the SARS-CoV-2 spike protein, and GX-19N containing plasmid DNA encoding ...the SARS-CoV-2 receptor-binding domain (RBD) foldon, nucleocapsid protein, and plasmid DNA encoding the spike protein.
Two open-label non-randomised phase 1 trials, one of GX-19 and the other of GX-19N were done at two hospitals in South Korea. We enrolled healthy adults aged 19–49 years for the GX-19 trial and healthy adults aged 19–54 years for the GX-19N trial. Participants who tested positive by serological testing for SARS-CoV-2 were excluded. At 4-week intervals, the GX-19 trial participants received two vaccine doses (either 1·5 mg or 3·0 mg), and the GX-19N trial participants received two 3·0 mg doses. The vaccines were delivered intramuscularly using an electroporator. The participants were followed up for 52 weeks after first vaccination. Data collected up to day 57 after first vaccination were analysed in this interim analysis. The primary outcome was safety within 28 days after each vaccination measured in the intention-to-treat population. The secondary outcome was vaccine immunogenicity using blood samples collected on day 43 or 57 after first vaccination measured in the intention-to-treat population. The GX-19 (NCT044445389) and GX-19N (NCT04715997) trials are registered with ClinicalTrials.gov.
Between June 17 and July 30, 2020, we screened 97 individuals, of whom 40 (41%) participants were enrolled in the GX-19 trial (20 50% in the 1·5 mg group and 20 50% in the 3·0 mg group). Between Dec 28 and 31, 2020, we screened 23 participants, of whom 21 (91%) participants were enrolled on the GX-19N trial. 32 (52%) of 61 participants reported 80 treatment-emergent adverse events after vaccination. All solicited adverse events were mild except one (2%) case of moderate fatigue in the 1·5 mg GX-19 group; no serious vaccine-related adverse events were detected. Binding antibody responses increased after second dose of vaccination in all groups (p=0·0002 in the 1·5 mg GX-19 group; p<0·0001 in the 3·0 mg GX-19; and p=0·0004 for the spike protein and p=0·0001 for the RBD in the 3·0 mg GX-19N group).
GX-19 and GX-19N are safe and well tolerated. GX-19N induces humoral and broad SARS-CoV-2-specific T-cell responses. GX-19N shows lower neutralising antibody responses and needs improvement to enhance immunogenicity.
The Korea Drug Development Fund, funded by the Ministry of Science and ICT, Ministry of Trade, Industry, and Energy, and Ministry of Health and Welfare.
Thiopeptides exhibit potent antimicrobial activity against Gram-positive pathogens by inhibiting bacterial protein synthesis. Micrococcins are among the structurally simpler thiopeptides, but they ...have not been exploited in detail. This research involved a computational simulation of micrococcin P2 (MP2) docking in parallel with the structure–activity relationship (SAR) studied. The incorporation of particular nitrogen heterocycles in the side chain of MP2 enhances the antimicrobial activity. Micrococcin analogues 6c and 6d thus proved to be more effective against impetigo and C. difficile infection (CDI), respectively, as compared to current first-line treatments. Compound 6c also showed a shorter treatment period than that of a first-line treatment for impetigo. This may be attributed to its ability to downregulate pro-inflammatory cytokines. Compound 6d had no observed recurrence for C. difficile and exerted a minimal impact on the beneficial gut microbiome. Their pharmacokinetic properties and low toxicity profile make these compounds ideal candidates for the treatment of impetigo and CDI and validate their involvement in preclinical development.
We synthesized a series of acceptor–donor–acceptor-type small molecules (SIDPP-EE, SIDPP-EO, SIDPP-OE, and SIDPP-OO) consisting of a dithienosilole (SI) electron-donating moiety and two ...diketopyrrolopyrrole (DPP) electron-withdrawing moieties each bearing linear n-octyl (O) and/or branched 2-ethylhexyl (E) alkyl side chains. X-ray diffraction patterns revealed that SIDPP-EE and SIDPP-EO films were highly crystalline with pronounced edge-on orientation, whereas SIDPP-OE and SIDPP-OO films were less crystalline with a radial distribution of molecular orientations. Near-edge X-ray absorption fine structure spectroscopy disclosed an edge-on orientation with a molecular backbone tilt angle of ∼22° for both SIDPP-EE and SIDPP-EO. Our analysis of the molecular packing and orientation indicated that the shorter 2-ethylhexyl groups on the SI core promote tight π–π stacking of the molecular backbone, whereas n-octyl groups on the SI core hinder close π–π stacking to some degree. Conversely, the longer linear n-octyl groups on the DPP arms facilitate close intermolecular packing via octyl–octyl interdigitation. Quantum mechanics/molecular mechanics molecular dynamics simulations determined the optimal three-dimensional positions of the flexible alkyl side chains of the SI and DPP units, which elucidates the structural cause of the molecular packing and orientation explicitly. The alkyl-chain-dependent molecular stacking significantly affected the electrical properties of the molecular films. The edge-on oriented molecules showed high hole mobilities in organic field-effect transistors, while the radially oriented molecules exhibited high photovoltaic properties in organic photovoltaic cells. These results demonstrate that appropriate positioning of alkyl side chains can modulate crystallinity and molecular orientation in SIDPP films, which ultimately have a profound impact on carrier transport and photovoltaic performance.
(1) Background: Until now, several reports about pregnant women with confirmed coronavirus disease 2019 (COVID-19) have been published. However, there are no comprehensive systematic reviews ...collecting all case series studies on data regarding adverse pregnancy outcomes, especially association with treatment modalities. (2) Objective: We aimed to synthesize the most up-to-date and relevant available evidence on the outcomes of pregnant women with laboratory-confirmed infection with COVID-19. (3) Methods: PubMed, Scopus, MEDLINE, Google scholar, and Embase were explored for studies and papers regarding pregnant women with COVID-19, including obstetrical, perinatal, and neonatal outcomes and complications published from 1 January 2020 to 4 May 2020. Systematic review and search of the published literature was done using the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). (4) Results: In total, 11 case series studies comprising 104 pregnant women with COVID-19 were included in our review. Fever (58.6%) and cough (30.7%) were the most common symptoms. Other symptoms included dyspnea (14.4%), chest discomfort (3.9%), sputum production (1.0%), sore throat (2.9%), and nasal obstruction (1.0%). Fifty-two patients (50.0%) eventually demonstrated abnormal chest CT, and of those with ground glass opacity (GGO), 23 (22.1%) were bilateral and 10 (9.6%) were unilateral. The most common treatment for COVID-19 was administration of antibiotics (25.9%) followed by antivirals (17.3%). Cesarean section was the mode of delivery for half of the women (50.0%), although no information was available for 28.8% of the cases. Regarding obstetrical and neonatal outcomes, fetal distress (13.5%), pre-labor rupture of membranes (9.6%), prematurity (8.7%), fetal death (4.8%), and abortion (2.9%) were reported. There are no positive results of neonatal infection by RT-PCR. (5) Conclusions: Although we have found that pregnancy with COVID-19 has significantly higher maternal mortality ratio compared to that of pregnancy without the disease, the evidence is too weak to state that COVID-19 results in poorer maternal outcome due to multiple factors. The number of COVID-19 pregnancy outcomes was not large enough to draw a conclusion and long-term outcomes are yet to be determined as the pandemic is still unfolding. Active and intensive follow-up is needed in order to provide robust data for future studies.
The central purpose of this study was to examine whether peer influence has a greater impact on adolescent substance use than parental influence. This was a comparative study that examined ...cross-cultural applicability by applying the established findings and theoretical suggestions, such as social learning theory and social bonding theory in the United States, to a traditionally non-Western social context (South Korea). Although the theories have firmly established their explicability on adolescent delinquency and substance use in U.S. society, there are relatively few empirical studies to establish its generalizability in societies outside the U.S. and even fewer in such traditionally non-Western societies as South Korea. Using a nationwide sample of self-reported data from 3,188 junior high school students, estimations from multivariate analyses were used to compare the relative importance of peer and parental influence on adolescent substance (alcohol and tobacco) use. The findings from the current study supported both social learning theory and social bonding theory, suggesting that both peer and parental influence are significant in predicting the risks of adolescent substance use. Although parental influence was slightly greater than peer factors, the difference was negligible. The limitations, the unique social context of Korean society, and future research implications are then discussed.
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