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This paper presents FAST-LIVO2, a fast and direct LiDAR-inertial-visual odometry framework designed for accurate and robust state estimation in SLAM tasks, enabling real-time robotic applications. FAST-LIVO2 integrates IMU, LiDAR, and image data through an efficient error-state iterated Kalman filter (ESIKF). To address the dimensional mismatch between LiDAR and image measurements, we adopt a sequential update strategy. Efficiency is further enhanced using direct methods for LiDAR and visual data fusion: the LiDAR module registers raw points without extracting features, while the visual module minimizes photometric errors without relying on feature extraction. Both LiDAR and visual measurements are fused into a unified voxel map. The LiDAR module constructs the geometric structure, while the visual module links image patches to LiDAR points, enabling precise image alignment. Plane priors from LiDAR points improve alignment accuracy and are refined dynamically during the process. Additionally, an on-demand raycast operation and real-time image exposure estimation enhance robustness. Extensive experiments on benchmark and custom datasets demonstrate that FAST-LIVO2 outperforms state-of-the-art systems in accuracy, robustness, and efficiency. Key modules are validated, and we showcase three applications: UAV navigation highlighting real-time capabilities, airborne mapping demonstrating high accuracy, and 3D model rendering (mesh-based and NeRF-based) showcasing suitability for dense mapping. Code and datasets are open-sourced on GitHub to benefit the robotics community.

This article investigates the robust output regulation of linear uncertain singularly perturbed systems by output-feedback control. Due to the presence of extremely small perturbation parameters, numerical issues will arise when applying conventional robust regulator design techniques to the regular system. To handle the problem, a continuous-time output-feedback controller adopting the forwarding design technique is proposed by combining the internal model approach with singularly perturbed theory. In this manner, the circumvention of numerical issues and the resolution of robustness problems can be achieved. Additionally, the sampling of the transmissions between the plant and the controller is taken into account, leading to the proposed implementation of a dynamic output-based event-triggered strategy. As a result, the output regulation property becomes practical. To avoid Zeno behavior, the implementation ensures the existence of a strictly positive minimum intertime for the triggering instant sequence. The validity of the results is demonstrated through the presentation of a numerical example.

ABSTRACTMacroautophagy/autophagy, an evolutionarily conserved process, plays an important role in the regulation of immune inflammation and nervous system homeostasis. However, the exact role and mechanism of autophagy in pain is still unclear. Here, we showed that impaired autophagy flux mainly occurred in astrocytes during the maintenance of neuropathic pain. No matter the stage of neuropathic pain induction or maintenance, activation of autophagy relieved the level of pain, whereas inhibition of autophagy aggravated pain. Moreover, the levels of neuroinflammation and reactive oxygen species (ROS) were increased or decreased following autophagy inhibition or activation. Further study showed that inhibition of autophagy slowed the induction, but increased the maintenance of neuroinflammatory responses, which could be achieved by promoting the binding of TRAF6 (TNF receptor-associated factor 6) to K63 ubiquitinated protein, and increasing the levels of p-MAPK8/JNK (mitogen-activated protein kinase 8) and nuclear factor of kappa light polypeptide gene enhancer in B cells (NFKB/NF-κB). Impaired autophagy also reduced the protective effect of astrocytes on neurons against ROS stress because of the decrease in the level of glutathione released by astrocytes, which could be improved by activating the NFE2L2/NRF2 (nuclear factor, erythroid derived 2, like 2) pathway. We also demonstrated that simultaneous activation of autophagy and the NFE2L2 pathway further relieved pain, compared to activating autophagy alone. Our study provides an underlying mechanism by which autophagy participates in the regulation of neuropathic pain, and a combination of autophagy and NFE2L2 activation may be a new treatment approach for neuropathic pain.Abbreviation:3-MA: 3-methyladenine; 8-OHdG: 8-hydroxydeoxy-guanosine; ACTB: actin, beta; AMPAR: alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptor; ATG: autophagy-related; CAMK2/CaMKII: calcium/calmodulin-dependent protein kinase II; CCL7: chemokine (C-C motif) ligand 7; CGAS: cyclic GMP-AMP synthase; CQ: chloroquine; GABA: gamma-aminobutyrate; GCLC: glutamate-cysteine ligase, catalytic subunit; GFAP: glial fibrillary acidic protein; GSH: glutathione; HMOX1/HO-1: heme oxygenase 1; KEAP1: kelch-like ECH-associated protein 1; MAP1LC3/LC3-II: microtubule-associated protein 1 light chain 3 beta (phosphatidylethanolamine-conjugated form); MAPK: mitogen-activated protein kinase; MAPK1/ERK: mitogen-activated protein kinase 1; MMP2: matrix metallopeptidase 2; MAPK8/JNK: mitogen-activated protein kinase 8; MAPK14/p38: mitogen-activated protein kinase 14; NFE2L2/NRF2: nuclear factor, erythroid derived 2, like 2; NFKB/NF-κB: nuclear factor of kappa light polypeptide gene enhancer in B cells; ROS: reactive oxygen species; SLC12A5: solute carrier family 12, member 5; SNL: spinal nerve ligation; TLR4: toll-like receptor 4; TRAF6: TNF receptor-associated factor; TRP: transient receptor potential.

Visual-Inertial Odometry (VIO) has been developed from Simultaneous Localization and Mapping (SLAM) as a low-cost and versatile sensor fusion approach and attracted increasing attention in ground vehicle positioning. However, VIOs usually have the degraded performance in challenging environments and degenerated motion scenarios. In this paper, we propose a ground vehicle-based VIO algorithm based on the Multi-State Constraint Kalman Filter (MSCKF) framework. Based on a unified motion manifold assumption, we derive the measurement model of manifold constraints, including velocity, rotation, and translation constraints. Then we present a robust filter-based algorithm dedicated to ground vehicles, whose key is the real-time manifold noise estimation and adaptive measurement update. Besides, GNSS position measurements are loosely coupled into our approach, where the transformation between GNSS and VIO frame is optimized online. Finally, we theoretically analyze the system observability matrix and observability measures. Our algorithm is tested on both the simulation test and public datasets including Brno Urban dataset and Kaist Urban dataset. We compare the performance of our algorithm with classical VIO algorithms (MSCKF, VINS-Mono, R-VIO, ORB_SLAM3) and GVIO algorithms (GNSS-MSCKF, VINS-Fusion). The results demonstrate that our algorithm is more robust than other compared algorithms, showing a competitive position accuracy and computational efficiency.

To reveal the principle of the close effect about the EHL finite roller, contraposing the log-convex roller, the finite line contact EHL film shape and thickness were observed through self-made heavy-load optical EHL experimental device. Experiments were carried out under several different pressure and viscosity, and three groups of interference pictures were obtained under three different entrainment velocities. As the load increased, both the length and width of the roller contact area added, and the width of the contact zone in the end was larger than that in the centre, the close effect was more obvious; when the entrainment velocity and lubricant viscosity increased, the film thickness in the central roller became thicker while the increase in the roller end was little, the high film thickness difference enhanced the close effect. The entrainment velocity, load and lubricant viscosity all have great effect on the EHL characteristics of the finite roller.

To make further researches into the elastohydrodynamic lubrication properties of a finite line contact roller, oscillating experiments were carried out on made overload experimental rig for oil film measurement using optical interference technique. Film thickness and shape were measured in two kinds of viscosity polyisobutylene. This study indicates that both lubricant viscosity and roller entrainment velocity play an important role on EHL of finite line contacts. On motion, the more increase in viscosity or speed, the thicker the oil film thickness, simultaneity edge effect is distinctly intensified and film thickness increases less on roller end, difference of the film thickness is increased between roller end and the central. Above two parameters are significant for logarithmic profile roller in crowning design.

Spinel LiMn2O4 was modified with Y2O3 coating by a chemical process. The crystal structures of the as-prepared samples were investigated by X-ray diffraction (XRD). The charge/discharge characteristics of the modified samples were evaluated at different rates between 3.0 and 4.4V. The discharge capacities of 2.0 wt.% Y2O3-coated LiMn2O4 are 116 mAh•g−1, 99.7mAh•g−1, 93.3mAh•g−1 and 82.9mAh•g−1 at 0.1C, 0.5C, 1C and 2C rates (at 20◦C). The cycle abilities improvement of the spinel LiMn2O4 coated with Y2O3 are demonstrated at elevated temperature (55◦C) and high rates (2C). From the analysis of electrochemical impedance spectroscopy (EIS), the improvement of cycle ability may be attributed to the suppression on the formation of the passivating films and the reduction of Mn dissolution, which result from the surface modification with Y2O3.

In this paper, using a database of the University of Michigan Radio Astronomy Observatory at the radio frequencies (8 GHz and 14.5 GHz), we determined the variability time scales, and calculated the brightness temperature for 86 radio sources (29 BL Lacertae objects—BLs and 57 flat spectrum radio quasars—FSRQs). The time scales were found in the range of from 3 months to 16.27 years with an averaged value scale of 2.34 years. We obtained the following results: (1) The brightness temperature is in the range of log $T_{\rm b,var}$$=$10.98 to $T_{\rm b,var}$$=$15.35, which suggests that the Doppler factors are in the range of $\delta$$=$0.73 to $\delta$$=$20.74. The averaged values are $\langle\delta\rangle$$=$5.95$\pm$2.93 for 57 FSRQs and $\langle\delta\rangle$$=$5.08$\pm$2.63 for 29 BLs. (2) The radio luminosity, $L_{\rm ob}$, is found to be correlated with the radio Doppler factor, $\delta$, log$L_{\rm ob}$$=$(0.58$\pm$0.10) log$\delta^{3}$$+$43.49$\pm$0.21. (3) The viewing angles and the Lorentz factors were determined for 53 sources (15 BLs and 38 FSRQS) with available superluminal velocity (Zhang & Fan 2008, Chin. J. Astron. Astrophys, 8, 385). The averaged values are $\Gamma$$=$24.1$\pm$17.35 and $\theta$$=$8$.^\circ$7$\pm$3$.^{\circ}$5 for the FSRQs, and $\Gamma$$=$13.5$\pm$11.16 and $\theta$$=$12$^{\circ}\pm$7$^{\circ}$for the BLs.

In the present work, using the data base of the University of Michigan Radio Astronomy Observatory (UMRAO) at three radio frequencies (4.8 GHz, 8GHZ, and 14.5 GHz), we studied the polarization properties for 47 BL Lacertae objects: 38 radio selected BL Lac objects, 7 X-ray selected BL Lac objects, and two inter-middle objects (Mkn 421 and Mkn 501), and found that: (1) the polarizations at higher radio frequency is higher than those at lower frequency, (2) the variability of polarization at higher radio frequency is higher than those at lower frequency, (3) the polarization is correlated with the radio spectral index, (4) the polarization is correlated with the core-dominance parameter for those objects with known core-dominance parameters, suggesting that relativistic beaming could explain the polarization characteristic of BL Lacs.

This paper presents a new sol-gel process to prepare molybdenum oxide thin films. A molybdenum acetylacetonate sol was prepared by employing the system CH3COCH2COCH3/MoO3/C6H5CH3/HOCH2CH2OCH3. A molybdenum acetylacetonate gel was prepared by addition of aqueous NH3. Thermal gravimetry (TG) and differential thermal analyses (DTA) of the gel suggested that crystallization of MoO3occurs in a 140 K temperature range around 508°C. MoO3films were prepared on fused silica, Si (111) and Al2O3(012) substrates by annealing spin coating films of the sol in oxygen environment at 508°C. X-ray diffraction (XRD) showed that all films crystallize in α-MoO3structure, and crystallites on fused silica substrate are arbitrarily oriented while those on Si (111) and Al2O3(012) substrates oriented in the (010) direction. SEM investigations showed that MoO3grains of all films are randomly distributed, with a longitudinal dimension of about 1–5 μm and the film thickness is about 1 μm.

We have studied the effect of hole-doping on the established scenerio of the first-order Mott metal-insulator transition (MIT) at half-filling using dynamical mean-field theory and exact diagonalization technique. The Mott insulator state is changed into metallic state immediately as holes are doped into the system. The latter is expected to be Fermi liquid. The previously found unanalytical structure of MIT no longer exists for doping as small as 2 percent. We compare our results with that obtained from Gutzwiller approximation.

Abstract: In this paper, a new method, the step-reduction method, is proposed to investigate the dynamic response of the Bernoulli-Euler beams with arbitrary nonhomogeneity and arbitrary variable cross-section under arbitrary loads. Both free vibration and forced vibration of such beams are studied. The new method requires to discretize the space domain into a number of elements. Each element can be treated as a homogeneous one with uniform thickness. Therefore, the general analytical solution of homogeneous beams with uniform cross-section can be used in each element. Then, the general analytic solution of the whole beam in terms of initial parameters can be obtained by satisfying the physical and geometric continuity conditions at the adjacent elements. In the case of free vibration, the frequency equation in analytic form can be obtained, and in the case of forced vibration, a final solution in analytical form can also be obtained which is involved in solving a set of simultaneous algebraic equations with only two unknowns which are independent of the numbers of elements divided. The present analysis can also be extended to the study of the vibration of such beams with viscous and hysteretic damping and other kinds of beams and other structural elements with arbitrary nonhomogeneity and arbitrary variable thickness.

The title binuclear complex, [CuFe(CN)5(C8H21N5O2)(NO)]·2H2O or [CuFe(nelin)(CN)5(NO)]·2H2O (nelin is 5‐methyl‐5‐nitro‐3,7‐di­aza­nonane‐1,9‐di­amine) consists of discrete binuclear mixed‐metal species, with a Cu centre linked to an Fe centre through a cyano bridge, and two water mol­ecules of crystallization. In the complex, the CuIIion is coordinated by five N atoms and has a distorted square‐pyramidal geometry. The FeIIcentre is in a distorted octahedral environment.

$\gamma$-ray loud blazars (flat spectrum radio quasars—FSRQs and BL Lacertae objects—BLs) are very bright in the $\gamma$-ray bands, which is perhaps associated with a beaming effect. Therefore, one can expect that the $\gamma$-ray luminosity is correlated with the beaming factor. In this paper, we consider the relation between the radio Doppler factors and the $\gamma$-ray luminosities. Our analysis suggests that the $\gamma$-ray luminosity be strongly correlated with the factor of $\delta_R$for the whole sample, FSRQs, and BLs. When the effect of a common redshift is excluded, the correlation still exists for the FSRQs sub-sample, suggesting that the $\gamma$-rays are strongly beamed. However, a partial correlation analysis does not show any correlation for the small BL Lac sample.

We used data from the University of Michigan Radio Astronomy Observatory (UMRAO) at three different bands (4.8 GHz, 8 GHz, and 14.5 GHz) to calculate the radio spectral index and the averaged polarization in a sample of 92 flat spectrum radio quasars (FSRQs). We analyzed the relationship between the polarization and other physical parameters for these objects. The results show that: 1) the polarization and its variability at high radio frequencies are higher than those at lower frequencies, 2) the degree of linear polarization is correlated with the radio spectral index, suggesting that the synchrotron mechanism is responsible for the radio emission, 3) the polarization is correlated with the core-dominance parameter for those objects for which this parameter is known, which suggests that relativistic beaming could explain some polarization characteristics of FSRQs, and 4) the polarization and flux density variabilities are correlated. These results are similar to those found for RBLs in our previous work (Fan et al. 2006). However, the distributions in the averaged polarization and the spectral index in FSRQs are different from those in RBLs.

During a study of the nutritional requirements of clinical isolates of Escherichia coli, we found that 21 (7.0%) of 301 strains required nicotinamide to grow in minimal medium. The nicotinamide-requiring strains were present in 16 (15.8%) of 101 cultures of urine from young women with acute cystitis, in 5 (5.0%) of 100 stool specimens from healthy adults, and in none of 100 blood samples from adult patients with bacteremia. Most of the strains belonged to serogroup 018:K1:H7, were hemolytic, possessed type 1 fimbriae, and exhibited similar patterns of antibiotic susceptibility. Two of the urinary isolates expressed S fimbriae, and all 16 urinary isolates contained the sfaS homologue gene on their chromosomes. One of the stool isolates contained the sfaS gene. The urinary isolates closely resembled a large clone of E. coli that is reportedly associated with neonatal meningitis and sepsis. It may be possible to detect this and related clones by their requirement for nicotinamide and to screen strains for S fimbriae by relatively inexpensive hemagglutination methods, including the use of avian P1 antigens to detect mannose-resistant, non-P-fimbriated E. coli; the agglutination of bovine erythrocytes; and the use of bovine mucin to detect sialyl galactosides in S fimbriae.

Glycine betaine is a powerful osmoprotectant molecule present in the inner medulla of the kidneyand excreted into urine. It may be responsible for the ability of Escherichia coli to grow in hypertonic urine. Also, strains of E. coli that cause urinary tract infections may be more salttolerant than strains from other sites. To explore these questions, 301 isolates from blood, urine, or stool and 12 representative enteric strains wereexamined. Tolerance varied from 0.1 to 0.7 M NaCI (median, 0.5) in minimal medium. There wereno significant differences in salt tolerance by site of isolation. A salt-sensitive enteric strain that responded poorly to glycine betaine and mutant strains lacking the ability to synthesize or transport glycinebetaine did not grow well in hypertonic urine. Accumulation of glycine betaine appears to be a mechanism by which E. coli can adapt to external osmotic forces and grow in hypertonic urine.