No abstract

Noninvasive, repeated, and high-resolution imaging of the lymphatic vascular system plays an important role in studying the development and function of lymphatics. However, conventional imaging modality such as magnetic resonance imaging (MRI) and X-ray lymphangiography shows insufficient temporal and spatial resolution and can only visualize large lymphatic vessels. Herein, we developed polymer dots as a novel lymphatic agent for simultaneously imaging the lymphatic capillary plexus and collecting lymphatic vessels in living mice/rats at a fast temporal resolution and high spatial resolution by combination with probe-based confocal laser endomicroscopy (pCLE). The imaging effect was verified by whole-body near-infrared fluorescence and photoacoustic imaging as well as ex vivo two-photon microscope imaging. Our study provides a novel approach for using polymer dots for high-resolution lymphatic vascular imaging in small animals.

In mobile underwater environment, underwater wireless sensor networks(UWSNs) keep moving and dispersing due to water flowing and aquatic creatures touching, and thus some isolated nodes appear. This type of isolated nodes cannot obtain enough anchor nodes in their communication range, which makes self-localizations disabled. In order to solve this problem, a multi-hop localization scheme is proposed in this paper. Firstly, ordinary nodes between anchors and unknown nodes are set as routers to find the shortest paths by a greedy approach; secondly, the shortest paths are approximately fitted into a straight distance between two nodes; finally, the positions of unknown nodes can be calculated by trilateration. The proposed algorithm is simulated and is compared with other algorithms in terms of localization error, and the results are proven preferable.