SiC MOSFETs (silicon carbide metal-oxide semiconductor field-effect transistors) are replacing Si insulated gate bipolar transistors in many power conversion applications due to their superior ...performance. However, ruggedness and reliability of SiC MOSFETs are still big concern for their widespread applications in the market, especially in safety-critical applications. The objective of this study is to provide a comprehensive picture on the ruggedness and reliability of commercial SiC MOSFETs, discover their failure or degradation mechanism, and propose some possible mitigation methods through both literature survey and in-depth analysis. The ruggedness of SiC MOSFETs discussed here includes short-circuit (SC) ruggedness, avalanche ruggedness, and their failure mechanism. The reliability issues include gate oxide reliability, degradation under high-temperature bias stress, repetitive SC stress, avalanche stress, power cycling stress, body diode's surge current stress, and their degradation mechanism. Furthermore, this study discusses methods and solutions to improve their ruggedness and reliability.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Noroviruses (NoVs) and rotaviruses (RVs), the two most important causes of viral acute gastroenteritis, are found to recognise histo-blood group antigens (HBGAs) as receptors or ligands for ...attachment. Human HBGAs are highly polymorphic containing ABO, secretor and Lewis antigens. In addition, both NoVs and RVs are highly diverse in how they recognise these HBGAs. Structural analysis of the HBGA-binding interfaces of NoVs revealed a conserved central binding pocket (CBP) interacting with a common major binding saccharide (MaBS) of HBGAs and a variable surrounding region interacting with additional minor binding saccharides. The conserved CBP indicates a strong selection of NoVs by the host HBGAs, whereas the variable surrounding region explains the diverse recognition patterns of different HBGAs by NoVs and RVs as functional adaptations of the viruses to human HBGAs. Diverse recognition of HBGAs has also been found in bacterial pathogen Helicobacter pylori. Thus, exploratory research into whether such diverse recognitions also occur for other viral and bacterial pathogens that recognise HBGAs is warranted.
Primary lung cancer is one of the most common malignant tumors in China. Approximately 60% of lung cancer patients have distant metastasis at the initial diagnosis, so it is necessary to find new ...tumor markers for early diagnosis and individualized treatment. Tumor markers contribute to the early diagnosis of lung cancer and play important roles in early detection and treatment, as well as in precision medicine, efficacy monitoring, and prognosis prediction. The pathological diagnosis of lung cancer in small biopsy specimens determines whether there are tumor cells in the biopsy and tumor type. Because biopsy is traumatic and the compliance of patients with multiple biopsies is poor, liquid biopsy has become a hot research direction. Liquid biopsies are advantageous because they are nontraumatic, easy to obtain, reflect the overall state of the tumor, and allow for real-time monitoring. At present, liquid biopsies mainly include circulating tumor cells, circulating tumor DNA, exosomes, microRNA, circulating RNA, tumor platelets, and tumor endothelial cells. This review introduces the research progress and clinical application prospect of liquid biopsy technology for lung cancer.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study presents an analytical investigation based on thermodynamic simulation aimed at achieving a holistic management of the phase assemblages of alkali-activated materials (AAMs) and gaining ...insights into the designing of precursors. Gibbs free energy minimization method was conducted on AAMs spanning the compositional envelopes at (metastable) thermodynamic equilibrium. The stability regions and quantities of simulated phases were identified in the SiO2-CaO-Al2O3 ternary contour diagrams, yielding the overall relationships between the chemical components of precursors, phase assemblages and pH in pore solution. The analytical results are in good agreement with the available experimental observations that the main precipitation regions of C-(N-)A-S-H appear at CaO/SiO2 = ~1.0 and relatively low Al regions while N-A-S-H phases generally dominate the Ca-deficient regions of the contour diagrams. Strätlingite mainly occurs at intermediate levels of Si, Al and Ca. Katoite and AFm phases form at Al2O3/CaO = ~3.0 under Si-deficient conditions. The findings also suggest the precipitation regions of a product may span a range of pH of aqueous solution, making it possible to simultaneously control pH and maintain the precipitation amount of the phase. The application of this work in designing precursors can achieve a more precise control of the phase assemblages for AAMs.
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•A holistic management of the solid phases of alkali-activated materials (AAMs) can be achieved by thermodynamic modelling.•Gibbs free energy minimization method was conducted on AAMs spanning the relevant compositional envelopes.•SiO2-CaO-Al2O3 ternary contour diagrams show the precipitation regions and quantities of each solid phase in AAMs.•The relationships between chemical components of precursors, hydrate assemblages and pH in pore solution were explored.•A more precise control of the phase assemblages can be achieved for AAMs based on this work.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Acute coronary syndromes (ACS) remain life-threatening disorders, which are associated with high morbidity and mortality. Dual antiplatelet therapy with aspirin and clopidogrel has been shown to ...reduce cardiovascular events in patients with ACS. However, there is substantial inter-individual variability in the response to clopidogrel treatment, in addition to prolonged recovery of platelet reactivity as a result of irreversible binding to P2Y12 receptors. This high inter-individual variability in treatment response has primarily been associated with genetic polymorphisms in the genes encoding for cytochrome (CYP) 2C19, which affect the pharmacokinetics of clopidogrel. While the US Food and Drug Administration has issued a boxed warning for CYP2C19 poor metabolizers because of potentially reduced efficacy in these patients, results from multivariate analyses suggest that additional factors, including age, sex, obesity, concurrent diseases and drug-drug interactions, may all contribute to the overall between-subject variability in treatment response. However, the extent to which each of these factors contributes to the overall variability, and how they are interrelated, is currently unclear. The objective of this review article is to provide a comprehensive update on the different factors that influence the pharmacokinetics and pharmacodynamics of clopidogrel and how they mechanistically contribute to inter-individual differences in the response to clopidogrel treatment.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The discovery of human histo-blood group antigens (HBGAs) as receptors or ligands of noroviruses (NoVs) raises a question about the potential role of host factors in the evolution and diversity of ...NoVs. Recent structural analysis of selected strains in the two major genogroups of human NoVs (GI and GII) demonstrated highly conserved HBGA binding interfaces within the two groups but not between them, indicating convergent evolution of GI and GII NoVs. GI and GII NoVs are probably introduced to humans from different non-human hosts with the HBGAs as a common niche. Each genogroup has further diverged into multiple sub-lineages (genotypes) through selections by the polymorphic HBGAs of the hosts. An elucidation of such pathogen–host interaction, including determination of the phenotypes of NoV–HBGAs interaction for each genotype, is important in understanding the epidemiology, classification and disease control and prevention of NoVs. A model of this multi-selection of NoVs by HBGAs is proposed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Increasing amounts of data also showed that many bacterial and other viral pathogens rely on a carbohydrate receptor for infection 17. ...the requirement of a carbohydrate receptor could be a ...convergent factor in the evolution of these bacterial and viral pathogens.\n One possibility is that a functional co-receptor necessary for norovirus replication is missing in the cell culture, although failures of additional downstream steps of viral replication also may be the reason. In the laboratory a single residue mutation around receptor-binding interfaces can result in a change of HBGA binding patterns 8, 29. ...it would be of significance to explore whether the consensus receptor binding patterns can switch between two genotypes in nature and whether GII.4 noroviruses will continue to dominate or will be replaced by other genotypes in future epidemics.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A NiCl2-promoted 2 + 2 + 1 carboannulation of 1,7-enynes with internally oxidative cyclobutanone oximes to produce canyo-functionalized 4H-cyclopentacquinolin-4-ones is disclosed. Through C–C/N–O ...bond cleavage and C–H functionalization, the process enables one-carbon incorporation using cyclobutanone oximes to achieve 2 + 2 + 1 carboannulation of 1,7-enynes, which is highlighted by allowing the formation of four new bonds with high selectivity and broad substrate scope.
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IJS, KILJ, NUK, PNG, UL, UM
Effects of fuel variability involving small fluctuations in fuel composition on physicochemical properties of premixed biogas-hydrogen combustion are quantified using global sensitivity analysis ...approach. Different proportions of hydrogen addition, and different CH4:CO2 ratios in biogas-hydrogen fuel with uncertainties are investigated from a statistical point of view. Analyses show that small fluctuation of biogas-hydrogen fuel composition does not lead to significant fluctuations in physicochemical properties of combustion such as laminar flame speed and adiabatic flame temperature. A fast growth of laminar flame speed fluctuation from lean to rich combustion of biogas-hydrogen fuel is observed implying a less stable flame at rich condition, and lower dimensional studies show that hydrogen uncertainty takes predominant responsibility for the rapid increase of flame speed. Apart from the uncertainty of hydrogen, it is found that carbon dioxide concentration fluctuation has a larger negative effect on stabilising biogas-hydrogen flame compared to that of methane. It is also found that for biogas-hydrogen fuel with high hydrogen content, contribution of carbon dioxide variability to flame speed fluctuation decreases while methane contribution increases.
•Effects of small fluctuation of fuel composition on premixed biogas-hydrogen combustion are quantified.•Dominating compositions to variation of biogas-hydrogen combustion properties are identified.•Flame speed fluctuation is mainly caused by hydrogen variability.•Effect of hydrogen content on flame stabilisation is influenced by methane concentration.•Near-linear increase of flame speed fluctuation is observed without hydrogen variability.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Lithium-sulfur batteries are promising next-generation energy storage devices due to their high energy density and low material cost. Efficient conversion of lithium polysulfides to lithium sulfide ...(during discharge) and to sulfur (during recharge) is a performance-determining factor for lithium-sulfur batteries. Here we show that MoS2-x/reduced graphene oxide (MoS2-x/rGO) can be used to catalyze the polysulfide reactions to improve the battery performance. It was confirmed, through microstructural characterization of the materials, that sulfur deficiencies on the surface participated in the polysulfide reactions and significantly enhanced the polysulfide conversion kinetics. The fast conversion of soluble polysulfides decreased their accumulation in the sulfur cathode and their loss from the cathode by diffusion. Hence in the presence of a small amount of MoS2-x/rGO (4 wt% of the cathode mass), high rate (8C) performance of the sulfur cathode was improved from a capacity of 161.1 mA h g-1 to 826.5 mA h g-1. In addition, MoS2-x/rGO also enhanced the cycle stability of the sulfur cathode from a capacity fade rate of 0.373% per cycle (over 150 cycles) to 0.083% per cycle (over 600 cycles) at a typical 0.5C rate. These results provide direct experimental evidence for the catalytic role of MoS2-x/rGO in promoting the polysulfide conversion kinetics in the sulfur cathode.
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