On the Sample Complexity of Multichannel Frequency Estimation via Convex Optimization

The use of multichannel data in line spectral estimation (or frequency estimation) is common for improving the estimation accuracy in array processing, structural health monitoring, wireless communications, and more. Recently proposed atomic norm methods have attracted considerable attention due to their provable superiority in accuracy, flexibility and robustness compared with conventional approaches. In this paper, we analyze atomic norm minimization for multichannel frequency estimation from noiseless compressive data, showing that the sample size per channel that ensures exact estimation decreases with the increase of the number of channels under mild conditions. In particular, given $L$ channels, order $K\left(\log K\right) \left(1+\frac{1}{L}\log N\right)$ samples per channel, selected randomly from $N$ equispaced samples, suffice to ensure with high probability exact estimation of $K$ frequencies that are normalized and mutually separated by at least $\frac{4}{N}$. Numerical results are provided corroborating our analysis.Comment: 14 pages, double column, to appear in IEEE Trans. Information Theor

Dexmedetomidine reduces inflammation in mice with acute pancreatitis by inhibiting NLRP3 inflammasome and sympathetic nerve activity

Purpose: To study the anti-inflammatory influence of dexmedetomidine (DEX) in mice with acute pancreatitis (AP), and to determine the underlying mechanism.Methods: A total of 75 healthy ICR male mice were randomly divided into control, mild acute pancreatitis (MAP), MAP+DEX, severe acute pancreatitis (SAP), and SAP+DEX groups, with 15 mice/group. Blood levels of inflammatory factors (TNF-α and IL-1β) and norepinephrine were assayed ineach group. Western blotting was used to assay the protein expressions of NLRP3 and norepinephrine transporter (NET) in the pancreatic tissue of each group.Results: The levels of inflammatory factors in the MAP+DEX group were markedly lower than those in the MAP group after 10 h of MAP induction (p < 0.01). Mice in MAP+DEX group had significantly lower expression of NLRP3 in pancreatic tissue, and significantly higher NET protein level, relative to the MAP mice. Following 10 h of SAP, concentrations of the inflammatory factors and the pancreatic expression of NLRP3 were lower in SAP+DEX-treated mice than in SAP mice, while NET protein was significantly higher in SAP mice (p < 0.01).Conclusion: DEX reduces the expressions of inflammation-related factors TNF-α and IL-1β, and inhibits inflammatory response in mice with AP via downregulation of NET protein expression via inhibition of NLRP3 and early sympathetic events. Keywords: Dexmedetomidine, NLRP3 inflammasome, Sympathetic nerve, Acute pancreatitis, Inflammatory respons

Current Status on Leaching Precious Metals from Waste Printed Circuit Boards

AbstractCurrent research on leaching precious metals from waste printed circuit boards (PCBs) in the world is introduced. In the paper, hydrometallurgical processing techniques including cyanide leaching, thiourea leaching, thiosulfate leaching, and halide leaching of precious metals are addressed in detail. In order to develop an environmentally friendly technique for recovery of precious metals from Waste PCBs, a critical comparison of main leaching methods is analyzed based on three-scale analytic hierarchy process (AHP). The results suggest that thiourea leaching and iodide leaching make more possible to replace cyanide leaching

Time-varying resonant mass at collider and beam dump experiments

A new particle usually manifests itself as a single resonant peak located at its mass. We propose if the new particle mass is time-varying due to environmental effects, then its mass spectrum typically has a novel double-peak feature. A representative model is the kinetic mixing dark photon interacting with an ultralight complex scalar dark matter charged under U(1)\u27. We reanalyze the existing experiments, showing the constraints on such a model are drastically weakened than those on the traditional single-peak resonance model, due to the reduction of the luminosity exposure in each resonant mass bin. Consequently, for mass around tens of MeV, the muon gμ -2 solution from the kinetic mixing dark photon becomes viable again. The scenario can be further tested by reanalyzing the existing data with timing information included

Hierarchical Feature Alignment Network for Unsupervised Video Object Segmentation

Optical flow is an easily conceived and precious cue for advancing unsupervised video object segmentation (UVOS). Most of the previous methods directly extract and fuse the motion and appearance features for segmenting target objects in the UVOS setting. However, optical flow is intrinsically an instantaneous velocity of all pixels among consecutive frames, thus making the motion features not aligned well with the primary objects among the corresponding frames. To solve the above challenge, we propose a concise, practical, and efficient architecture for appearance and motion feature alignment, dubbed hierarchical feature alignment network (HFAN). Specifically, the key merits in HFAN are the sequential Feature AlignMent (FAM) module and the Feature AdaptaTion (FAT) module, which are leveraged for processing the appearance and motion features hierarchically. FAM is capable of aligning both appearance and motion features with the primary object semantic representations, respectively. Further, FAT is explicitly designed for the adaptive fusion of appearance and motion features to achieve a desirable trade-off between cross-modal features. Extensive experiments demonstrate the effectiveness of the proposed HFAN, which reaches a new state-of-the-art performance on DAVIS-16, achieving 88.7 $\mathcal{J}\&\mathcal{F}$ Mean, i.e., a relative improvement of 3.5% over the best published result.Comment: Accepted by ECCV-202

Lysine residues of interferon regulatory factor 7 affect the replication and transcription activatormediated lytic replication of Kaposi’s sarcomaassociated herpesvirus/human herpesvirus 8

Kaposi’s sarcoma-associated herpesvirus (KSHV) infection goes through latent and lytic phases, which are controlled by the viral replication and transcription activator (RTA). Upon KSHV infection, the host responds by suppressing RTA-activated lytic gene expression through interferon regulatory factor 7 (IRF-7), a key regulator of host innate immune response. Lysine residues are potential sites for post-translational modification of IRF-7, and were suggested to be critical for its activity. In this study, we analysed the 15 lysine residues for their effects on IRF-7 function by site-directed mutagenesis. We found that some mutations affect the ability of IRF-7 to activate interferon (IFN)-a1 and IFN-b promoters, to suppress RTA-mediated lytic gene expression and to repress KSHV reactivation and lytic replication. However, other mutations affect only a subset of these four functions. These findings demonstrate that the lysine residues of IRF-7 play important roles in mediating IFN synthesis and modulating viral lytic replication

Allelic Interactions among Pto-MIR475b and Its Four Target Genes Potentially Affect Growth and Wood Properties in Populus

MicroRNAs (miRNAs) play crucial roles in plant growth and development, but few studies have illuminated the allelic interactions among miRNAs and their targets in perennial plants. Here, we combined analysis of expression patterns and single-nucleotide polymorphism (SNP)-based association studies to explore the interactions between Pto-MIR475b and its four target genes (Pto-PPR1, Pto-PPR2, Pto-PPR3, and Pto-PPR4) in 435 unrelated individuals of Populus tomentosa. Expression patterns showed a significant negative correlation (r = -0.447 to -0.411, P < 0.01) between Pto-MIR475b and its four targets in eight tissues of P. tomentosa, suggesting that Pto-miR475b may negatively regulate the four targets. Single SNP-based association studies identified 93 significant associations (P < 0.01, Q < 0.1) representing associations of 80 unique SNPs in Pto-MIR475b and its four targets with nine traits, revealing their potential roles in tree growth and wood formation. Moreover, one common SNP in the precursor region significantly altered the secondary structure of the pre-Pto-miR475b and changed the expression level of Pto-MIR475b. Analysis of epistatic interactions identified 115 significant SNP–SNP associations (P < 0.01) representing 45 unique SNPs from Pto-MIR475b and its four targets for 10 traits, revealing that genetic interactions between Pto-MIR475b and its targets influence quantitative traits of perennial plants. Our study provided a feasible strategy to study population genetics in forest trees and enhanced our understanding of miRNAs by dissecting the allelic interactions between this miRNA and its targets in P. tomentosa