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In the autonomous navigation of mobile robots, precise positioning is crucial. In forest environments with weak satellite signals or in sites disturbed by complex environments, satellite positioning accuracy has difficulty in meeting the requirements of autonomous navigation positioning accuracy for robots. This article proposes a vision SLAM/UWB tightly coupled localization method and designs a UWB non-line-of-sight error identification method using the displacement increment of the visual odometer. It utilizes the displacement increment of visual output and UWB ranging information as measurement values and applies the extended Kalman filtering algorithm for data fusion. This study utilized the constructed experimental platform to collect images and ultra-wideband ranging data in outdoor environments and experimentally validated the combined positioning method. The experimental results show that the algorithm outperforms individual UWB or loosely coupled combination positioning methods in terms of positioning accuracy. It effectively eliminates non-line-of-sight errors in UWB, improving the accuracy and stability of the combined positioning system. [ABSTRACT FROM AUTHOR]

Abstract: Autotrophic domestication for short-cut nitrification (SCN) and microorganism immobilization was carried out in a lab-scale biological aerated filters (BAFs) system with activated sludge. Zeolite was chosen as fillings and modified to enlarge the specific surface and to remove toxic metal ions. After thirty-day domestication and immobilization, the removal capacity increased to 76.51mg/g dry sludge (DS) and the ratio of converted from reached to 91.2% finally. The analysis of growth kinetics indicated that free ammonia should be the key factor for SCN. The abundance variation of nitrifiers, measured by qPCR, showed that AOB was enriched successfully and NOB was washed out. The results also showed that modified zeolite should be more beneficial to the specific immobilization of AOB than natural zeolite. The shift in the community structure of AOB during the domestication by DGGE profile was investigated. [Copyright &y& Elsevier]

Summary Postsynaptic densities (PSDs) are membrane semi-enclosed, submicron protein-enriched cellular compartments beneath postsynaptic membranes, which constantly exchange their components with bulk aqueous cytoplasm in synaptic spines. Formation and activity-dependent modulation of PSDs is considered as one of the most basic molecular events governing synaptic plasticity in the nervous system. In this study, we discover that SynGAP, one of the most abundant PSD proteins and a Ras/Rap GTPase activator, forms a homo-trimer and binds to multiple copies of PSD-95. Binding of SynGAP to PSD-95 induces phase separation of the complex, forming highly concentrated liquid-like droplets reminiscent of the PSD. The multivalent nature of the SynGAP/PSD-95 complex is critical for the phase separation to occur and for proper activity-dependent SynGAP dispersions from the PSD. In addition to revealing a dynamic anchoring mechanism of SynGAP at the PSD, our results also suggest a model for phase-transition-mediated formation of PSD. [ABSTRACT FROM AUTHOR]