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Continuous hemodynamic monitoring in a wearable means can play a crucial role in managing hypertension and preventing catastrophic cardiovascular events. In this study, we have described the fully wearable tonometric device, referred to as flexible adaptive sensing tonometry (FAST), which is capable of continuous and accurate monitoring of hemodynamic parameters within the medical-grade precision. In particular, the FAST system integrates a 1 × 8 unit array of highly sensitive and highly flexible iontronic sensing (FITS) with 1 mm spatial resolution and a closed-loop motion system. The flexible tonometric architecture has been used to determine the radial arterial position with high sensitivity and high conformability, which simplifies the biaxial searching process of the traditional applanation tonometry into a highly efficient uniaxial applanation while keeping the medical-precision assessments. Importantly, a self-calibration algorithm can be automatically implemented during the applanation process, from which the intra-arterial blood pressure wave can be continuously predicted within the medical-grade precision, and subsequently, multi-parametric hemodynamic analysis can be performed in real-time. Experimental validations on health volunteers have demonstrated that the FAST measurements are all within the required accuracy of the clinical standards for continuous pulse wave assessments, blood pressure monitoring as well as other key hemodynamic parameter evaluations. Therefore, the FAST system, by integrating the flexible iontronic sensing array, provides a real-time, medical-grade hemodynamic monitoring solution in a continuously wearable manner, from which remote patient-centered monitoring can be delivered with both medical precision and convenience. [ABSTRACT FROM AUTHOR]

β-Chiral sulfones are structural motifs widely found in natural products and bioactive molecules, while also serving as important intermediates for the synthesis of valuable chiral scaffolds. In contrast to the rapid growth of sulfur dioxide insertion chemistry over the last decade, enantioselective catalytic variants for accessing β-chiral sulfones, especially those bearing a quaternary carbon stereocenter, remain rare. Herein, we report an enantioselective copper/bisoxazoline catalyzed oxysulfonylation of alkenes to yield isoxazolinyl-containing β-chiral sulfones bearing quaternary carbon stereocenters with moderate to excellent yields and up to 96:4 er. The advantage and irreplaceability of this sulfur dioxide insertion catalytic system have been demonstrated by achieving transformations clearly unavailable with the previously reported sulfonyl chloride system. Additionally, the recoverability of the new-developed bisoxazoline ligand L9 and its reusability without any erosion of the catalytic activity and enantioselectivity further demonstrate the usefulness of the protocol. [ABSTRACT FROM AUTHOR]

Antler ossified tissue has been widely used for the extraction of bioactive peptides. In this study, collagen was prepared from antler ossified tissue via acetic acid and pepsin. Five different proteases were used to hydrolyze the collagen and the hydrolysate treated by neutrase (collagen peptide named ACP) showed the highest DPPH radical clearance rate. The extraction process of ACP was optimized by response surface methodology, and the optimal conditions were as follows: a temperature of 52 °C, a pH of 6.1, and an enzyme concentration of 3200 U/g, which resulted in the maximum DPPH clearance rate of 74.41 ± 0.48%. The peptides (ACP-3) with the strongest antioxidant activity were obtained after isolation and purification, and its DPPH free radical clearance rate was 90.58 ± 1.27%; at the same time, it exhibited good scavenging activity for ABTS, hydroxyl radical, and superoxide anion radical. The study investigated the protective effect of ACP-3 on oxidative damage in HaCaT cells. The findings revealed that all groups that received ACP-3 pretreatment exhibited increased activities of SOD, GSH-Px, and CAT compared to the model group. Furthermore, ACP-3 pretreatment reduced the levels of ROS and MDA in HaCaT cells subjected to H2O2-induced oxidative damage. These results suggest that collagen peptides derived from deer antler ossified tissue can effectively mitigate the oxidative damage caused by H2O2 in HaCaT cells, thereby providing a foundation for the utilization of collagen peptides in pharmaceuticals and cosmetics. [ABSTRACT FROM AUTHOR]

The perfectly matched layer (PML), proposed by Berenger, has been proved very effective in absorbing propagating waves in lossless media. However, it has been found that the original construction of PML cannot effectively absorb evanescent waves. Also, significant reflection can appear as PML is applied to terminate lossy media. This paper describes a generalized perfectly matched layer (GPML) that extends the original PML to absorb both propagating and evanescent waves in lossless and lossy media. The generalized perfectly matched layer is derived from the Maxwell s equations in stretched coordinates and can be easily implemented in finite-difference time-domain (FDTD) programs. This paper also presents proper selection of parameters in the numerical implementation of the generalized perfectly matched layer to achieve good performance in absorption.

This paper presents some numerical implementation issues and the performance of Berenger's perfectly matched layer (PML) boundary condition for modeling wave propagation in waveguide structures by the finite-difference time-domain (FDTD) method. The relation between the thickness and the conductivity profile of the perfectly matched layer is studied and a guideline for the selection of PML parameters is given. It is shown that the standard Yee's time-marching scheme results in virtually the same numerical solution as the exponential time-marching scheme. Numerical tests are provided for parallel-plate and rectangular waveguides and microstrip lines. It is found that PML is very effective in absorbing TEM and quasi-TEM waves, as well as nonTEM waves somewhat above cutoff frequencies, but ineffective in absorbing evanescent waves and nonTEM waves near cutoff frequencies. The reason for the ineffectiveness of PML for absorbing evanescent waves is explained. Comparative study of PML and Higdon's boundary condition shows that high-order Higdon's boundary condition can reach the same performance of 16-cell PML and can be adjusted for absorbing evanescent waves, but PML is in general more robust to implement. Performance of the boundary condition obtained by combining PML and Higdon's boundary condition is evaluated.

A general expression of an absorbing boundary condition is presented in this paper to model wave propagation in passive microwave integrated-circuits by the finite-difference time-domain method. Unlike previously developed absorbing boundary conditions which can only absorb propagating waves, this boundary condition can also absorb evanescent waves effectively. The microstrip line is used as an example to demonstrate how to impose this absorbing boundary condition on different outer boundaries of a computation-domain. It is also demonstrated that the numerical stability of this absorbing boundary condition, when it is applied in its high order form, can be maintained by properly selecting its parameters.

Since the finite-difference time-domain method was proposed for the solution of Maxwell's equations, various absorbing boundary conditions have been developed to simulate the infinite large space with a finite computation domain. In this paper, we propose a novel technique, which we call 'superabsorption,' to improve absorbing boundary conditions. This method can be applied to every known absorbing boundary condition and yield dramatic reduction on the numerical error caused by the boundary reflection. The principle and analysis of the superabsorption method are presented. Numerical tests are made indicating the improvements on many absorbing boundary conditions by using this technique.

Presents information on a study which evaluated the closed-form crosstalk models used for the estimation of near and far end crosstalk voltages between two parallel transmission lines. Transmission line equations for two coupled lines; Line matching conditions; Examples of crosstalk voltage waveforms; Conclusions.

Antler bone calcium (AB-Ca) and bioactive peptides (ABPs) were extracted from antler bones ( Cervus elaphus ) to maximize their value. In this study, 0.14 g calcium was obtained from 1 g antler bone. The peptide-calcium chelate rate was 53.68 ± 1.80%, and the Gly, Pro, and Glu in ABPs were identified to donate most to the increased calcium affinity through the mass spectrometry. Fourier transform infrared spectroscopy showed that calcium predominantly interacted with amino nitrogen atoms and carboxyl oxygen atoms, thereby generating a peptide-calcium chelate. The peptide-calcium chelates were characterized using scanning electron microscopy. A Caco-2 cell monolayer model showed that ABPs significantly increased calcium transport. Furthermore, the D-gal-induced aging mouse model indicated that the ABPs + AB-Ca group showed higher Ca and PINP levels, lower P, ALP, and CTX-1content in serum, and considerably higher tibia index and tibia calcium content. Results showed that ABPs + AB-Ca increased bone formation and inhibited bone resorption, thereby providing calcium supplements for ameliorating senile osteoporosis (SOP).