68 research outputs found

    Isoflavone Content of Soybean Cultivars from Maturity Group 0 to VI Grown in Northern and Southern China

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    Soybean isoflavone content has long been considered to be a desirable trait to target in selection programs for their contribution to human health and plant defense systems. The objective of this study was to determine isoflavone concentrations of various soybean cultivars from maturity groups 0 to VI grown in various environments and to analyze their relationship to other important seed characters. Forty soybean cultivars were grown in replicated trials at Wuhan and Beijing of China in 2009/2010 and their individual and total isoflavone concentrations were determined by HPLC. Their yield and quality traits were also concurrently analyzed. The isoflavone components had abundant genetic variation in soybean seed, with a range of coefficient variation from 45.01% to 69.61%. Moreover, individual and total isoflavone concentrations were significantly affected by cultivar, maturity group, site and year. Total isoflavone concentration ranged from 551.15 to 7584.07 μg g(−1), and averaged 2972.64 μg g(−1) across environments and cultivars. There was a similar trend regarding the isoflavone contents, in which a lower isoflavone concentration was generally presented in early rather than late maturing soybean cultivars. In spite of significant cultivar × year × site interactions, cultivars with consistently high or low isoflavone concentrations across environments were identified, indicating that a genetic factor plays the most important role for isoflavone accumulation. The total isoflavone concentration had significant positive correlations with plant height, effective branches, pods per plant, seeds per plant, linoleic acid and linolenic acid, while significant negative correlations with oleic acid and oil content, indicating that isoflavone concentration can be predicted as being associated with other desirable seed characteristics

    Patients with IBD have a more cautious attitude towards COVID-19 vaccination

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    BackgroundTo understand the awareness of COVID-19 vaccine, the willingness to vaccinate and the influencing factors of willingness to vaccinate in inflammatory bowel disease (IBD) patients.MethodsThe online questionnaire was distributed to conduct a survey to analyze and evaluate the willingness, awareness and trust in vaccines of IBD patients. Bivariate analyses and logistic regression models were used to analysis influencing factors.ResultsWe sent the questionnaire to the WeChat group for patient management and 304 patients responded, out of which 16 respondents had to be excluded and 288 respondents were included for the analysis. Among them, 209 patients vaccinated with COVID-19 vaccine. Among the non-vaccinated 79 patients, the main reasons for their concerns were afraid of vaccination aggravating IBD and fear of adverse effects. Our results showed that IBD patients with long disease duration were more willing to receive COVID-19 vaccination (P<0.05). We also observed that a high perception of benefits and cues to action to receive the vaccine were the two most important constructs affecting a definite intention for COVID-19 vaccination (P<0.05).ConclusionsPatients with IBD have a more cautious attitude towards COVID-19 vaccination, which may lead to a higher rate of vaccine hesitancy. Further efforts should be made to protect patients with IBD from COVID-19 infections and achieve adequate vaccination coverage

    A cross-reactive human IgA monoclonal antibody blocks SARS-CoV-2 spike-ACE2 interaction

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    COVID-19 caused by SARS-CoV-2 has become a global pandemic requiring the development of interventions for the prevention or treatment to curtail mortality and morbidity. No vaccine to boost mucosal immunity, or as a therapeutic, has yet been developed to SARS-CoV-2. In this study, we discover and characterize a cross-reactive human IgA monoclonal antibody, MAb362. MAb362 binds to both SARS-CoV and SARS-CoV-2 spike proteins and competitively blocks ACE2 receptor binding, by overlapping the ACE2 structural binding epitope. Furthermore, MAb362 IgA neutralizes both pseudotyped SARS-CoV and SARS-CoV-2 in 293 cells expressing ACE2. When converted to secretory IgA, MAb326 also neutralizes authentic SARS-CoV-2 virus while the IgG isotype shows no neutralization. Our results suggest that SARS-CoV-2 specific IgA antibodies, such as MAb362, may provide effective immunity against SARS-CoV-2 by inducing mucosal immunity within the respiratory system, a potentially critical feature of an effective vaccine

    Numerical study on inertial effects on liquid-vapor flow using lattice Boltzmann method

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    Liquid-vapor flow in porous media is studied in this article. To fulfill this goal, a double-distribution-function lattice Boltzmann (LB) model is proposed based on the separate-phase governing equations at the representative elementary volume (REV) scale. Importantly, besides the Darcy force and capillary force, which were commonly included in previous studies, the LB model in this article also considers the inertial force characterized by the Forchheimer term. This feature enables the model to offer an effective description of liquid-vapor flow in porous media at low, intermediate and even high flow rates. We validated the LB model by simulating a single-phase flow in porous media driven by a pressure difference and found its results are in good agreement with the available analytical solutions. We then applied the model to study water-vapor flow in a semi-infinite porous region bounded by an impermeable and heated wall. The numerical simulation reveals the flow and mass transfer characteristics under the compounding effects of inertial, Darcy and capillary forces. Through a comparison with the results given by the generalized Darcy’s law, our numerical results directly evidence that the inertial force is a dominating factor when a fluid passes through porous media at an intermediate or high flow rate

    Investigation Of Waffle Structure Scr For Electro-Static Discharge (Esd) Protection

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    The waffle layout SCR-based ESD protection device is presented and analyzed in this paper. This waffle structure with symmetrical layout is designed to generate more current paths to distribute ESD currents better. TLP I-V measurement results show that, the stand-alone waffle layout SCR costs only 39 percent silicon area of conventional stripe layout SCR, but can achieve better ESD robustness. Results also show that the trigger voltage and current handling ability of waffle layout SCR can be adjustable to meet different operating demands by changing the device dimensions. © 2012 IEEE

    Silicon-Controlled Rectifier Stacking Structure For High-Voltage Esd Protection Applications

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    Latchup immunity is a challenging issue for the design of power supply clamps used in high-voltage electrostatic discharge (ESD) protection applications. While silicon-controlled rectifiers (SCRs) are highly robust ESD devices, they are traditionally not suited for high-voltage ESD due to their inherent low holding voltage and, thus, vulnerability to latchup. In this letter, a novel SCR stacking structure with an extremely high holding voltage, very small snapback, and acceptable failure current has been developed. The new and existing high holding voltage ESD devices are also compared to demonstrate the advancement of this work. © 2010 IEEE

    Silicon Controlled Rectifier (Scr) Compact Modeling Based On Vbic And Gummel-Poon Models

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    Silicon controlled rectifier (SCR) is frequently used for electrostatic discharge (ESD) protection applications. For computer-aided design purposes, a macromodel can be constructed for such a device, but a model for the NPN and PNP bipolar transistors imbedded in the SCR is required in the macromodel development. In the paper, we use both the Vertical Bipolar Inter-Company (VBIC) and SPICE Gummel-Poon (SGP) models for these bipolar transistors and compare the perspective macromodel results. Measurements obtained from the transmission line pulsing (TLP) tester are also included to assess the suitability and pros and cons of the VBIC and SGP models for the SCR ESD modeling. © 2008 Elsevier Ltd. All rights reserved
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