Multi-sensor Suboptimal Fusion Student's tt Filter

A multi-sensor fusion Student's $t$ filter is proposed for time-series recursive estimation in the presence of heavy-tailed process and measurement noises. Driven from an information-theoretic optimization, the approach extends the single sensor Student's $t$ Kalman filter based on the suboptimal arithmetic average (AA) fusion approach. To ensure computationally efficient, closed-form $t$ density recursion, reasonable approximation has been used in both local-sensor filtering and inter-sensor fusion calculation. The overall framework accommodates any Gaussian-oriented fusion approach such as the covariance intersection (CI). Simulation demonstrates the effectiveness of the proposed multi-sensor AA fusion-based $t$ filter in dealing with outliers as compared with the classic Gaussian estimator, and the advantage of the AA fusion in comparison with the CI approach and the augmented measurement fusion.Comment: 8 pages, 8 figure

Atomic-Scale Tracking Phase Transition Dynamics of Berezinskii-Kosterlitz-Thouless Polar Vortex-Antivortex

Particle-like topologies, such as vortex-antivortex (V-AV) pairs, have garnered significant attention in the field of condensed matter. However, the detailed phase transition dynamics of V-AV pairs, as exemplified by self-annihilation, motion, and dissociation, have yet to be verified in real space due to the lack of suitable experimental techniques. Here, we employ polar V-AV pairs as a model system and track their transition pathways at atomic resolution with the aid of in situ (scanning) transmission electron microscopy and phase field simulations. We demonstrate the absence of a Berezinskii-Kosterlitz-Thouless phase transition between the room-temperature quasi-long-range ordered ground phase and the high-temperature disordered phase. Instead, we observe polarization suppression in bound V-AV pairs as the temperature increases. Furthermore, electric fields can promote the vortex and antivortex to approach each other and annihilate near the interface. The elucidated intermediate dynamic behaviors of polar V-AV pairs under thermal- and electrical-fields lay the foundation for their potential applications in electronic devices. Moreover, the dynamic behaviors revealed at atomic scale provide us new insights into understanding topological phase of matter and their topological phase transitions.Comment: 19 pages and 4 figure

Molecular Characterization and Tissue Localization of an F-Box Only Protein from Silkworm, Bombyx mori

The eukaryotic F-box protein family is characterized by an F-box motif that has been shown to be critical for the controlled degradation of regulatory proteins. We identified a gene encoding an F-box protein from a cDNA library of silkworm pupae, which has an ORF of 1821 bp, encoding a predicted 606 amino acids. Bioinformatic analysis on the amino acid sequence shows that BmFBXO21 has a low degree of similarity to proteins from other species, and may be related to the regulation of cell-cycle progression. We have detected the expression pattern of BmFBXO21 mRNA and protein and performed immunohistochemistry at three different levels. Expression was highest in the spinning stage, and in the tissues of head, epidermis, and genital organs

Thermodynamic behavior of correlated electron-hole fluids in van der Waals heterostructures

Coupled two-dimensional electron-hole bilayers provide a unique platform to study strongly correlated Bose-Fermi mixtures in condensed matter. Electrons and holes in spatially separated layers can bind to form interlayer excitons, composite Bosons expected to support high-temperature exciton superfluids. The interlayer excitons can also interact strongly with excess charge carriers when electron and hole densities are unequal. Here, we use optical spectroscopy to quantitatively probe the local thermodynamic properties of strongly correlated electron-hole fluids in MoSe2/hBN/WSe2 heterostructures. We observe a discontinuity in the electron and hole chemical potentials at matched electron and hole densities, a definitive signature of an excitonic insulator ground state. The excitonic insulator is stable up to a Mott density of ~$0.8\times {10}^{12} \mathrm{cm}^{-2}$ and has a thermal ionization temperature of ~70 K. The density dependence of the electron, hole, and exciton chemical potentials reveals strong correlation effects across the phase diagram. Compared with a non-interacting uniform charge distribution, the correlation effects lead to significant attractive exciton-exciton and exciton-charge interactions in the electron-hole fluid. Our work highlights the unique quantum behavior that can emerge in strongly correlated electron-hole systems

Performance Evaluation Metrics and Approaches for Target Tracking: A Survey

Performance evaluation (PE) plays a key role in the design and validation of any target-tracking algorithms. In fact, it is often closely related to the definition and derivation of the optimality/suboptimality of an algorithm such as that all minimum mean-squared error estimators are based on the minimization of the mean-squared error of the estimation. In this paper, we review both classic and emerging novel PE metrics and approaches in the context of estimation and target tracking. First, we briefly review the evaluation metrics commonly used for target tracking, which are classified into three groups corresponding to the most important three factors of the tracking algorithm, namely correctness, timeliness, and accuracy. Then, comprehensive evaluation (CE) approaches such as cloud barycenter evaluation, fuzzy CE, and grey clustering are reviewed. Finally, we demonstrate the use of these PE metrics and CE approaches in representative target tracking scenarios

Microarray Expression Profile of Circular RNAs in Plasma from Primary Biliary Cholangitis Patients

Background/Aims: Circular RNAs (circRNAs) play a crucial role in the occurrence of several diseases, including autoimmune diseases. However, their role in primary biliary cholangitis (PBC) remains unclear. Here, we aimed to determine the circRNA expression profile in plasma from PBC patients and further explore the value of circRNA in diagnosing PBC. Methods: CircRNA microarrays were used to determine circRNA expression profiles in plasma samples from 6 PBC patients and 6 healthy controls. Statistical analyses identified differentially expressed circRNAs, and these circRNAs were verified by qRT-PCR in 29 PBC patients and 30 healthy controls. MicroRNA (miRNA) target prediction software identified putative miRNA response elements (MREs), which were used to construct a map of circRNA-miRNA interactions for the differentially expressed circRNAs. Results: Our results indicated that there were 18 up-regulated and 4 down-regulated circular RNAs in the plasma from PBC patients compared with that from healthy individuals. Among the differentially expressed circRNAs, hsa_circ_402458 (P=0.0033), hsa_circ_087631 and hsa_circ_406329 (P=0.0185) were up-regulated, and hsa_circ_407176 (P=0.0066) and hsa_circ_082319 were down-regulated in the PBC group versus the healthy group as demonstrated by qRT-PCR. In particular, hsa_circ_402458 was significantly higher in PBC patients not receiving UDCA treatment than in PBC patients receiving UDCA treatment (P=0.0338). The area under the receiver operating characteristic curve for hsa_circ_402458 for diagnosing PBC was 0.710 (P=0.005). For hsa_circ_402458, two putative miRNA targets, hsa-miR-522-3p and hsa-miR-943, were predicted. Conclusions: circRNA dysregulation may play a role in PBC pathogenesis, and hsa_circ_402458 shows promise as a candidate biomarker for PBC

Mid-Infrared Multispectral Gaseous Stimulated Raman Scattering Laser

We demonstrated mid-infrared gaseous stimulated Raman scattering lasers in free space. Mixed gases of hydrogen and deuterium were used as Raman gain media in one Raman cell. Pumped by laser pulses at 1064 nm, the first Stokes Raman components at 1560 nm and 1907 nm were generated. A four-wave mixing process with the pump laser at 1064 nm and Raman lasers at 1560 nm and 1907 nm contributed to dramatically reducing the threshold of mid-IR laser generation at 4432 nm. The maximum output peak power of a mid-IR laser at 4432 nm reached 121 kW. Furthermore, by scattering on the rotational transition of deuterium, multispectral mid-IR Raman lasers at wavelengths of 2071 nm, 2266 nm, 2604 nm, 2920 nm, 3322 nm, 3743 nm, 4432 nm, and 5431 nm were also generated. Our results show that this is a convenient method to reduce the threshold and achieve a high power output with mid-IR Raman lasers

Mid-Infrared Multispectral Gaseous Stimulated Raman Scattering Laser

We demonstrated mid-infrared gaseous stimulated Raman scattering lasers in free space. Mixed gases of hydrogen and deuterium were used as Raman gain media in one Raman cell. Pumped by laser pulses at 1064 nm, the first Stokes Raman components at 1560 nm and 1907 nm were generated. A four-wave mixing process with the pump laser at 1064 nm and Raman lasers at 1560 nm and 1907 nm contributed to dramatically reducing the threshold of mid-IR laser generation at 4432 nm. The maximum output peak power of a mid-IR laser at 4432 nm reached 121 kW. Furthermore, by scattering on the rotational transition of deuterium, multispectral mid-IR Raman lasers at wavelengths of 2071 nm, 2266 nm, 2604 nm, 2920 nm, 3322 nm, 3743 nm, 4432 nm, and 5431 nm were also generated. Our results show that this is a convenient method to reduce the threshold and achieve a high power output with mid-IR Raman lasers

Tiny endoscopic optical coherence tomography probe driven by a miniaturized hollow ultrasonic motor

We present an endoscopic probe for optical coherence tomography (OCT) equipped with a miniaturized hollow ultrasonic motor that rotates the objective lens and provides an internal channel for the fiber to pass through, enabling 360 deg unobstructed circumferential scanning. This probe has an outer diameter of 1.5 mm, which is ultra-small for motorized probes with an unobstructed view in distal scanning endoscopic OCT. Instead of a mirror or prism, a customized aspheric right-angle lens is utilized, leading to an enlargement of the numerical aperture and thus high transverse resolution. Spectral-domain OCT imaging of bio-tissue and a phantom are demonstrated with resolution of 7.5  μm (axial) × 6.6  μm (lateral) and sensitivity of 96 dB