Distributed Extended Object Tracking Using Coupled Velocity Model from WLS Perspective

This study proposes a coupled velocity model (CVM) that establishes the relation between the orientation and velocity using their correlation, avoiding that the existing extended object tracking (EOT) models treat them as two independent quantities. As a result, CVM detects the mismatch between the prior dynamic model and actual motion pattern to correct the filtering gain, and simultaneously becomes a nonlinear and state-coupled model with multiplicative noise. The study considers CVM to design a feasible distributed weighted least squares (WLS) filter. The WLS criterion requires a linear state-space model containing only additive noise about the estimated state. To meet the requirement, we derive such two separate pseudo-linearized models by using the first-order Taylor series expansion. The separation is merely in form, and the estimates of interested states are embedded as parameters into each other's model, which implies that their interdependency is still preserved in the iterative operation of two linear filters. With the two models, we first propose a centralized WLS filter by converting the measurements from all nodes into a summation form. Then, a distributed consensus scheme, which directly performs an inner iteration on the priors across different nodes, is proposed to incorporate the cross-covariances between nodes. Under the consensus scheme, a distributed WLS filter over a realistic network with ``naive'' node is developed by proper weighting of the priors and measurements. Finally, the performance of proposed filters in terms of accuracy, robustness, and consistency is testified under different prior situations.Comment: Corrected Versio

Strengthening and microbial regulation mechanism of Bacillus on purification device for grass carp culture wastewater

Aquaculture wastewater (AW) poses a threat to natural aquatic environments. Microecological agents are widely used to regulate and purify AW, with Bacillus being the most common. To evaluate the AW purification effect of adding Bacillus subtilis and Bacillus licheniformis to an AW treatment device, we constructed an experimental device including a small grass carp culture pond and three groups of cuboid reactors. The effects of adding the two strains to the AW treatment reactor on the AW purification effect and the microbiota compositions in the AW and packing surface biofilm were analyzed via high-throughput sequencing of the 16S rRNA gene. Our results showed that adding Bacillus bacteria to reactors improved the total nitrogen (TN) removal efficiency and reduced the chemical oxygen demand (COD). Adding both the B. subtillis and B. licheniformis preparations significantly increased the abundance of Firmicutes in the water microbiota of the reactor at the middle and end stages of the experiment. The addition of Bacillus changed the microbiota composition in the water and packing surface biofilm and significantly increased the abundance of Bacillus at the middle and later stages of the experiment. Therefore, the addition of Bacillus improved the TN removal efficiency in the AW grass carp treatment reactors and significantly reduced the COD in the AW by increasing the abundance of Bacillus and changing the microbiota composition in the system. We provide an effective way for improving the purification capacity of biofilm reactor

Identification of potential inhibitors of omicron variant of SARS-Cov-2 RBD based virtual screening, MD simulation, and DFT

Emergence of the SARS-CoV-2 Omicron variant of concern (VOC; B.1.1.529) resulted in a new peak of the COVID-19 pandemic, which called for development of effective therapeutics against the Omicron VOC. The receptor binding domain (RBD) of the spike protein, which is responsible for recognition and binding of the human ACE2 receptor protein, is a potential drug target. Mutations in receptor binding domain of the S-protein have been postulated to enhance the binding strength of the Omicron VOC to host proteins. In this study, bioinformatic analyses were performed to screen for potential therapeutic compounds targeting the omicron VOC. A total of 92,699 compounds were screened from different libraries based on receptor binding domain of the S-protein via docking and binding free energy analysis, yielding the top 5 best hits. Dynamic simulation trajectory analysis and binding free energy decomposition were used to determine the inhibitory mechanism of candidate molecules by focusing on their interactions with recognized residues on receptor binding domain. The ADMET prediction and DFT calculations were conducted to determine the pharmacokinetic parameters and precise chemical properties of the identified molecules. The molecular properties of the identified molecules and their ability to interfere with recognition of the human ACE2 receptors by receptor binding domain suggest that they are potential therapeutic agents for SARS-CoV-2 Omicron VOC

TRIM9-Mediated Resolution of Neuroinflammation Confers Neuroprotection upon Ischemic Stroke in Mice

Excessive and unresolved neuroinflammation is a key component of the pathological cascade in brain injuries such as ischemic stroke. Here, we report that TRIM9, a brain-specific tripartite motif (TRIM) protein, was highly expressed in the peri-infarct areas shortly after ischemic insults in mice, but expression was decreased in aged mice, which are known to have increased neuroinflammation after stroke. Mechanistically, TRIM9 sequestered β-transducin repeat-containing protein (β-TrCP) from the Skp-Cullin-F-box ubiquitin ligase complex, blocking IκBα degradation and thereby dampening nuclear factor κB (NF-κB)-dependent proinflammatory mediator production and immune cell infiltration to limit neuroinflammation. Consequently, Trim9-deficient mice were highly vulnerable to ischemia, manifesting uncontrolled neuroinflammation and exacerbated neuropathological outcomes. Systemic administration of a recombinant TRIM9 adeno-associated virus that drove brain-wide TRIM9 expression effectively resolved neuroinflammation and alleviated neuronal death, especially in aged mice. These findings reveal that TRIM9 is essential for resolving NF-κB-dependent neuroinflammation to promote recovery and repair after brain injury and may represent an attractive therapeutic target

Ion Management And Mass Transport For (photo-) Electrochemical Conversions

(Photo-) electrochemistry hold great potential for storing the surplus energy of renewably generated electrons in the form of energy-dense chemicals that can be stored for long periods of time at low cost. The efficiency of converting between electrical- and chemical- energy depends on the charge transfer kinetics at the anode and cathode, as well as ion and mass transport; the latter two have been shown to cause energy losses comparable to those of the electrode charge transfer processes. The first three chapters of the thesis explore the use of bipolar membranes (BPMs) for managing ion transport in CO2 electrolysis, fuel cells, and redox flow batteries, while focusing on understanding the fundamental aspects of BPMs. Chapter 1 introduces the potential of using electrolysis for renewable energy storage and summarizes recent progress in BPM research. In Chapter 2, we combine electrochemical impedance spectroscopy and finite element method based numerical modeling to elucidate the relation between the electric field and interfacial catalysis in enhancing water dissociation reaction in BPMs. Chapter 3 presents the results of managing interfacial protons in a BPM-based CO2 electrolyzer. The acidic local environment at the membrane/catalyst interface facilitates the competing hydrogen evolution reaction and leads to a low CO2 reduction efficiency. This problem was mitigated by coating the membrane with a weak acid polyelectrolyte film of ~ 50 nm, the local pH within which was monitored using ratiometric pH indicators covalently attached to the polyelectrolyte. Chapter 4 explores the forward-biased BPM in a redox flow battery that operates the positive/negative electrode in an alkaline/acidic environment. This unique configuration enables a battery potential that is ~ 0.7 V higher than the conventional ones using a single pH condition. The acid-base recombination reaction was found to be inefficient in forward-biased BPMs, being rate-limited by the narrow reaction zone in the junction region. In chapter 5, we designed a novel architecture for the catalyst layer in alkaline fuel cells, which allows for a better control of the microstructure and thus the study of mass transport in a membrane electrode assembly (MEA) configuration. The last chapter summaries the thesis and proposes future directions

Ion Management and Mass Transport for (Photo-) Electrochemical Conversions

(Photo-) electrochemistry hold great potential for storing the surplus energy of renewably generated electrons in the form of energy-dense chemicals that can be stored for long periods of time at low cost. The efficiency of converting between electrical- and chemical- energy depends on the charge transfer kinetics at the anode and cathode, as well as ion and mass transport; the latter two have been shown to cause energy losses comparable to those of the electrode charge transfer processes. The first three chapters of the thesis explore the use of bipolar membranes (BPMs) for managing ion transport in CO2 electrolysis, fuel cells, and redox flow batteries, while focusing on understanding the fundamental aspects of BPMs. Chapter 1 introduces the potential of using electrolysis for renewable energy storage and summarizes recent progress in BPM research. In Chapter 2, we combine electrochemical impedance spectroscopy and finite element method based numerical modeling to elucidate the relation between the electric field and interfacial catalysis in enhancing water dissociation reaction in BPMs. Chapter 3 presents the results of managing interfacial protons in a BPM-based CO2 electrolyzer. The acidic local environment at the membrane/catalyst interface facilitates the competing hydrogen evolution reaction and leads to a low CO2 reduction efficiency. This problem was mitigated by coating the membrane with a weak acid polyelectrolyte film of ~ 50 nm, the local pH within which was monitored using ratiometric pH indicators covalently attached to the polyelectrolyte. Chapter 4 explores the forward-biased BPM in a redox flow battery that operates the positive/negative electrode in an alkaline/acidic environment. This unique configuration enables a battery potential that is ~ 0.7 V higher than the conventional ones using a single pH condition. The acid-base recombination reaction was found to be inefficient in forward-biased BPMs, being rate-limited by the narrow reaction zone in the junction region. In chapter 5, we designed a novel architecture for the catalyst layer in alkaline fuel cells, which allows for a better control of the microstructure and thus the study of mass transport in a membrane electrode assembly (MEA) configuration. The last chapter summaries the thesis and proposes future directions