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Computational fluid dynamics (CFD) simulations have shown great potentials in cardiovascular disease diagnosis and postoperative assessment. Patient‐specific and well‐tuned boundary conditions are key to obtaining accurate and reliable hemodynamic results. However, CFD simulations are usually performed under non‐patient‐specific flow conditions due to the absence of in vivo flow and pressure measurements. This study proposes a new method to overcome this challenge by tuning inlet boundary conditions using data extracted from electrocardiogram (ECG). Five patient‐specific geometric models of type B aortic dissection were reconstructed from computed tomography (CT) images. Other available data included stoke volume (SV), ECG, and 4D‐flow magnetic resonance imaging (MRI). ECG waveforms were processed to extract patient‐specific systole to diastole ratio (SDR). Inlet boundary conditions were defined based on a generic aortic flow waveform tuned using (1) SV only, and (2) with ECG and SV (ECG + SV). 4D‐flow MRI derived inlet boundary conditions were also used in patient‐specific simulations to provide the gold standard for comparison and validation. Simulations using inlet flow waveform tuned with ECG + SV not only successfully reproduced flow distributions in the descending aorta but also provided accurate prediction of time‐averaged wall shear stress (TAWSS) in the primary entry tear (PET) and abdominal regions, as well as maximum pressure difference, ∆Pmax, from the aortic root to the distal false lumen. Compared with simulations with inlet waveform tuned with SV alone, using ECG + SV in the tuning method significantly reduced the error in false lumen ejection fraction at the PET (from 149.1% to 6.2%), reduced errors in TAWSS at the PET (from 54.1% to 5.7%) and in the abdominal region (from 61.3% to 11.1%), and improved ∆Pmax prediction (from 283.1% to 18.8%) However, neither of these inlet waveforms could be used for accurate prediction of TAWSS in the ascending aorta. This study demonstrates the importance of SDR in tailoring inlet flow waveforms for patient‐specific hemodynamic simulations. A well‐tuned flow waveform is essential for ensuring that the simulation results are patient‐specific, thereby enhancing the confidence and fidelity of computational tools in future clinical applications. [ABSTRACT FROM AUTHOR]

Optical information storage, in virtue of its large capacity, high stability, and long longevity, holds promising prospects in mass storage, while being limited by the trade‐off between readout quality and error rate. The emerging intersection of optical storage and deep learning presents a valuable opportunity to achieve high‐fidelity data storage. Here, a novel paradigm of error‐free long‐lifespan optical storage enhanced is proposed by deep learning, harnessing neural network to extract optical information from birefringence measurements. It is demonstrated that using neural networks outperforms traditional approaches in terms of efficiency and accuracy. Moreover, by adding extra birefringence information as input to the neural network, nearly 100%$100\%$ accuracy is achieved on an established five‐bit dataset. Remarkably, even under extremely severe ambiguity, the paradigm still fulfills error‐free readout and maintains a long lifespan. The experimental storage scheme is significantly conducive to the development of large‐scale error‐free storage, and paves the way for robust optical storage with environmental and temporal tolerance in practical scenarios. [ABSTRACT FROM AUTHOR]

A monolithic, fully coupled fluid‐structure interaction (FSI) computational framework was developed to account for dissection flap motion in acute type B aortic dissection (TBAD). Analysis of results included wall deformation, pressure, flow, wall shear stress (WSS), von Mises stress and comparison of hemodynamics between rigid wall and FSI models. Our FSI model mimicked realistic wall deformation that resulted in maximum compression of the distal true lumen (TL) by 21.4%. The substantial movement of intimal flap mostly affected flow conditions in the false lumen (FL). Flap motion facilitated more flow entering the FL at peak systole, with the TL to FL flow split changing from 88:12 in the rigid model to 83:17 in the FSI model. There was more disturbed flow in the FL during systole (5.8% FSI vs 5.2% rigid) and diastole (13.5% FSI vs 9.8% rigid), via a λ2 ‐criterion. The flap‐induced disturbed flow near the tears in the FSI model caused an increase of local WSS by up to 70.0% during diastole. This resulted in a significant reduction in the size of low time‐averaged WSS (TAWSS) regions in the FL (113.11 cm2 FSI vs 177.44 cm2 rigid). Moreover, the FSI model predicted lower systolic pressure, higher diastolic pressure, and hence lower pulse pressure. Our results provided new insights into the possible impact of flap motion on flow in aortic dissections, which are particularly important when evaluating hemodynamics of acute TBAD. Novelty Statement: Our monolithic fully coupled FSI computational framework is able to reproduce experimentally measured range of flap deformation in aortic dissection, thereby providing novel insights into the influence of physiological flap motion on the flow and pressure distributions. The drastic flap movement increases the flow resistance in the true lumen and causes more disturbed flow in the false lumen, as visualized through the λ2 criterion. The flap‐induced luminal pressure is dampened, thereby affecting pressure measures, which may serve as potential prognostic indicators for late complications in acute uncomplicated TBAD patients. [ABSTRACT FROM AUTHOR]

The Food and Drug Administration's (FDA) benchmark nozzle model has been studied extensively both experimentally and computationally. Although considerable efforts have been made on validations of a variety of numerical models against available experimental data, the transitional flow cases are still not fully resolved, especially with regards to detailed comparison of predicted turbulence quantities with experimental measurements. This study aims to fill this gap by conducting large‐eddy simulations (LES) of flow through the FDA's benchmark model, at a transitional Reynolds number of 2000. Numerical results are compared to previous interlaboratory experimental results, with an emphasis on turbulence characteristics. Our results show that the LES methodology can accurately capture laminar quantities throughout the model. In the pre‐jet breakdown region, predicted turbulence quantities are generally larger than high resolution experimental data acquired with laser Doppler velocimetry. In the jet breakdown regions, where maximum Reynolds stresses occur, Reynolds shear stresses show excellent agreement. Differences of up to 4% and 20% are observed near the jet core in the axial and radial normal Reynolds stresses, respectively. Comparisons between viscous and Reynolds shear stresses show that peak viscous shear stresses occur in the nozzle throat reaching a value of 18 Pa in the boundary layer, whilst peak Reynolds shear stresses occur in the jet breakdown region reaching a maximum value of 87 Pa. Our results highlight the importance in considering both laminar and turbulent contributions towards shear stresses and that neglecting the turbulence effect can significantly underestimate the total shear force exerted on the fluid. [ABSTRACT FROM AUTHOR]

Stabilized sulfur ylide mediated cyclopropanation and formal [4+1] cycloaddition of 3-acyl-2 H-chromenones and their imines were explored. The transformations could be performed under mild conditions and were shown to have wide substrate scopes and significant functional-group tolerance; furthermore, the reactions proceeded with excellent regioselectivity. Thus, they are powerful methods for the one-pot synthesis of highly functionalized cyclopropane- and dihydropyrrole-fused chromen-2-one derivatives. [ABSTRACT FROM AUTHOR]

In order to search for novel Protox inhibitors with high efficiency, broad-spectrum activity, and safety to crops, commercially herbicide butafenacil was used as lead compound for further optimization, a series of title compounds 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i were designed and synthesized by introducing benzothiazol-2-yl moiety into the uracil skeleton. The bioassays indicated that some of the target compounds displayed moderate herbicidal activities in the post-emergence treatment. [ABSTRACT FROM AUTHOR]

Inter-phase momentum coupling for particle flows is usually achieved by means of direct numerical simulation (DNS) or point source method (PSM). DNS requires the mesh size of the continuous phase to be much smaller than the size of the smallest particle in the system, whereas PSM requires the mesh size of the continuous phase to be much larger than the particle size. However, for applications where mesh sizes are similar to the size of particles in the system, neither DNS nor PSM is suitable. In order to overcome the dependence of mesh on particle sizes associated with DNS or PSM, a two-layer mesh method (TMM) is proposed. TMM involves the use of a coarse mesh to track the movement of particle clouds and a fine mesh for the continuous phase, with mesh interpolation for information exchange between the coarse and fine mesh Numerical tests of different interpolation methods show that a conservative interpolation scheme of the second order yields the most accurate results. Numerical simulations of a fluidized bed show that there is a good agreement between predictions using TMM with a second-order interpolation scheme and the experimental results, as well as predictions obtained with PSM. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY In this study, a fluid-structure interaction model (FSI) incorporating viscoelastic wall behaviour is developed and applied to an idealized model of the carotid artery under pulsatile flow. The shear and bulk moduli of the arterial wall are described by Prony series, where the parameters can be derived from in vivo measurements. The aim is to develop a fully coupled FSI model that can be applied to realistic arterial geometries with normal or pathological viscoelastic wall behaviour. Comparisons between the numerical and analytical solutions for wall displacements demonstrate that the coupled model is capable of predicting the viscoelastic behaviour of carotid arteries. Comparisons are also made between the solid only and FSI viscoelastic models, and the results suggest that the difference in radial displacement between the two models is negligible. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Mung bean starch acetate has been successfully produced with transesterification reaction of the starch under microwave assistance using vinyl acetate (VAC) as esterifying agent and potassium carbonate (K2CO3) as a catalyst. Various concentration of potassium carbonate (0-0.117 mmoleq/AGU) was resulted in starch acetate with increased mood of the degree of substitution (DS = 0.003-0.27) in a short time. An increase in the degree of substitution, resulting in increase of the peak intensity of ester carbonyl group (CO) at 1742 cm−1, which was further proved by FTIR. Obvious change in the starch granules morphology, increasing in the hyrophilicity and decreasing in the temperature and enthalpy of gelatinization were noticed accordingly to the degree of the starch modification. The X-ray pattern of native starch was A type, with similar pattern in modified derivatives. [ABSTRACT FROM AUTHOR]

Summary Two procedures for the isolation of volatiles from Liuyang douchi, the typical representative of Aspergillus-type douchi, were compared: solid-phase microextraction (SPME) and simultaneous steam distillation extraction (SDE). Compared with SDE, the SPME extract was judged to be more similar to the aroma of the starting materials. The aroma impact compounds of the SPME extract were then determined using GC-MS and gas chromatography-olfactometry (GC-O). From the detection frequencies and the intensities of the peaks, twenty-eight volatile compounds were detected in the sniffing port of GC-O. Identification of twenty-two aroma impact compounds was based on the combination of sensory descriptors, linear retention index values, GC-MS data and co-injection of authentic standards. Compounds with the greatest aroma intensities include 2-methyl-butanal, ethyl 2-methylbutyrate, isoamyl acetate, 2,6-dimethylpyrazine, 1-octen-3-ol, 2-pentyl furan, benzeneacetaldehyde, phenylethyl alcohol, phenethyl acetate and phenethyl butyrate. These compounds might have an impact on the overall aroma of Liuyang douchi. [ABSTRACT FROM AUTHOR]

The opening and closing dynamics of the aortic valve (AV) has a strong influence on haemodynamics in the aortic root, and both play a pivotal role in maintaining normal physiological functions of the valve. The aim of this study was to establish a subject‐specific fluid–structure interaction (FSI) workflow capable of simulating the motion of a tricuspid healthy valve and the surrounding haemodynamics under physiologically realistic conditions. A subject‐specific aortic root was reconstructed from magnetic resonance (MR) images acquired from a healthy volunteer, whilst the valve leaflets were built using a parametric model fitted to the subject‐specific aortic root geometry. The material behaviour of the leaflets was described using the isotropic hyperelastic Ogden model, and subject‐specific boundary conditions were derived from 4D‐flow MR imaging (4D‐MRI). Strongly coupled FSI simulations were performed using a finite volume‐based boundary conforming method implemented in FlowVision. Our FSI model was able to simulate the opening and closing of the AV throughout the entire cardiac cycle. Comparisons of simulation results with 4D‐MRI showed a good agreement in key haemodynamic parameters, with stroke volume differing by 7.5% and the maximum jet velocity differing by less than 1%. Detailed analysis of wall shear stress (WSS) on the leaflets revealed much higher WSS on the ventricular side than the aortic side and different spatial patterns amongst the three leaflets. [ABSTRACT FROM AUTHOR]