On the alternating target tracking of a point cloud on Riemannian manifolds.

We study finite-time and asymptotic tracking of a given moving target configuration. For this, we proposed two multi-agent systems on Riemannian manifolds based on Filippov's framework. For asymptotic tracking, we adopt a piecewise C1-vector field on Riemannian manifolds resulting from switching moving targets, whereas for finite-time tracking, we use a piecewise C0 and non-Lipschitzian vector field on Euclidean space. For both multi-agent systems, we provide several sufficient frameworks for the desired asymptotic or finite-time tracking that are formulated in terms of system parameters, a preassigned switching moving target configuration, kernel functionals, and initial data.

A Dual-Mode CMOS Power Amplifier with an External Power Amplifier Driver Using 40 nm CMOS for Narrowband Internet-of-Things Applications.

The narrowband Internet-of-Things (NB-IoT) has been developed to provide low-power, wide-area IoT applications. The efficiency of a power amplifier (PA) in a transmitter is crucial for a longer battery lifetime, satisfying the requirements for output power and linearity. In addition, the design of an internal complementary metal-oxide semiconductor (CMOS) PA is typically required when considering commercial applications to include the operation of an optional external PA. This paper presents a dual-mode CMOS PA with an external PA driver for NB-IoT applications. The proposed PA supports an external PA mode without degrading the performances of output power, linearity, and stability. In the operation of an external PA mode, the PA provides a sufficient gain to drive an external PA. A parallel-combined transistor method is adopted for a dual-mode operation and a third-order intermodulation distortion (IMD3) cancellation. The proposed CMOS PA with an external PA driver was implemented using 40 nm-CMOS technology. The PA achieves a gain of 20.4 dB, a saturated output power of 28.8 dBm, and a power-added efficiency (PAE) of 57.8% in high-power (HP) mode at 920 MHz. With an NB-IoT signal (200 kHz π/4-differential quadrature phase shift keying (DQPSK)), the proposed PA achieves 24.2 dBm output power (Pout) with a 31.0% PAE, while satisfying -45 dBc adjacent channel leakage ratio (ACLR). More than 80% of the current consumption at 12 dBm Pout could be saved compared to that in HP mode when the proposed PA operates in low-power (LP) mode. The implemented dual-mode CMOS PA provides high linear output power with high efficiency, while supporting an external PA mode. The proposed PA is a good candidate for NB-IoT applications.

Emergent dynamics of various Cucker-Smale type models with a fractional derivative.

In this paper, we demonstrate emergent dynamics of various Cucker-Smale type models, especially standard Cucker-Smale (CS), thermodynamic Cucker-Smale (TCS), and relativistic Cucker-Smale (RCS) with a fractional derivative in time variable. For this, we adopt the Caputo fractional derivative as a widely used standard fractional derivative. We first introduce basic concepts and previous properties based on fractional calculus to explain its unusual aspects compared to standard calculus. Thereafter, for each proposed fractional model, we provide several sufficient frameworks for the asymptotic flocking of the proposed systems. Unlike the flocking dynamics which occurs exponentially fast in the original models, we focus on the flocking dynamics that occur slowly at an algebraic rate in the fractional systems.

Interplay of unit-speed constraint and singular communication in the thermodynamic Cucker-Smale model.

We study collision avoidance resulting from unit-speed constraint and singular communication weight in a thermo-mechanical Cucker-Smale (TCS) flocking ensemble moving in a Euclidean space. The TCS model governs the flocking dynamics of the CS particles in the presence of a self-consistent temperature field. The issue of collision avoidance has been addressed in the realistic modeling of collective particle models, and it has been investigated in the CS and TCS models without unit-speed constraint. In this paper, we take one further step by examining how unit-speed constraint and singular communication weights can result in collision avoidance between particles. For this, we introduce a sufficient framework to ensure collision avoidance in terms of system parameters and initial data.

Effects of rutaecarpine on hydrogen peroxide-induced apoptosis in murine hepa-1c1c7 cells.

The aim of this study was to investigate the inhibitory effects of rutaecarpine on DNA strand breaks and apoptosis induced by hydrogen peroxide (H2O2) in murine Hepa-1c1c7 cells. Oxidative DNA damage was estimated by nuclear condensation assessment, fluorescence-activated cell sorting analysis, and Comet assay. Rutaecarpine inhibited cell death induced by 500 µM H2O2, as assessed by 4',6-diamidino-2-phenylindole (DAPI) staining. Treatment with rutaecarpine reduced the number of DNA strand breaks induced by H2O2, as assessed by DAPI staining and Comet assay, and increased quinone reductase, phosphatidylinositol 3-kinase, and pAkt protein levels, as assessed by western blotting.

Therapeutic effect of (Z)-3-(2,5-dimethoxyphenyl)-2-(4-methoxyphenyl) acrylonitrile (DMMA) against Staphylococcus aureus infection in a murine model.

Sortase enzymes belong to a family of transpeptidases found in Gram-positive bacteria. Sortase is responsible for the reaction that anchors surface protein virulence factors to the peptidoglycan cell wall of the bacteria. The compound (Z)-3-(2,5-dimethoxyphenyl)-2-(4-methoxyphenyl) acrylonitrile (DMMA) has previously been reported as a novel sortase inhibitor in vitro, but the in vivo effects of DMMA have not been studied. Here, we evaluated the in vivo effects of DMMA against infection by wild-type and sortase A- and/or sortase B-deficient Staphylococcus aureus in Balb/c mice. With DMMA treatment, survival rates increased and kidney and joint infection rates decreased (p<0.01) in a dose-dependent manner. The rate of kidney infection was significantly reduced in the mice treated with sortase A knock-out S. aureus (p<0.01). These results indicate that by acting as a potent inhibitor of sortase A and moderate inhibitor of sortase B, DMMA can decrease kidney and joint infection rates and reduce mortality in mice infected with S. aureus. These findings suggest that DMMA is a promising therapeutic compound against Gram-positive bacteria.

Induction of NAD(P)H: quinone reductase by rutaecarpine isolated from the fruits of Evodia rutaecarpa in the murine hepatic Hepa-1c1c7 cell line.

Rutaecarpine is a quinazolinocarboline alkaloid isolated from Evodia rutaecarpa (Juss.), which has been used in traditional Chinese medicine. The bioactivity-guided fractionation has led to the isolation of rutaecarpine from the extract of the fruits of E. rutaecarpa as the major component possessing NAD(P)H:quinone reductase (QR) activity. The activator protein-1 (AP-1), a transcriptional factor, in the antioxidant response element (ARE) region plays an important role in mediating induction of the target genes by xenobiotics, including chemopreventive agents. The present study demonstrates that rutaecarpine induces QR activity and gene expression by transactivation of AP-1. To study the induction of QR activity and AP-1-mediated QR gene expression by rutaecarpine, we performed enzyme and reporter gene assays. This compound markedly induced the enzyme activity and mRNA expression levels of QR in a dose-dependent manner. Using the luciferase reporter gene assay, a dose-dependent transactivation of AP-1-mediated luciferase expression was observed upon treatment of rutaecarpine. These results suggest that rutaecarpine induces QR gene expression and activity through an increase in AP-1 activation.