A deep learning approach to 3D segmentation of brain vasculature

The segmentation of blood-vessels is an important preprocessing step for the quantitative analysis of brain vasculature. We approach the segmentation task for two-photon brain angiograms using a fully convolutional 3D deep neural network.Published versio

Development of a beam propagation method to simulate the point spread function degradation in scattering media

Scattering is one of the main issues that limit the imaging depth in deep tissue optical imaging. To characterize the role of scattering, we have developed a forward model based on the beam propagation method and established the link between the macroscopic optical properties of the media and the statistical parameters of the phase masks applied to the wavefront. Using this model, we have analyzed the degradation of the point-spread function of the illumination beam in the transition regime from ballistic to diffusive light transport. Our method provides a wave-optic simulation toolkit to analyze the effects of scattering on image quality degradation in scanning microscopy. Our open-source implementation is available at https://github.com/BUNPC/Beam-Propagation-Method.Accepted manuscrip

Microstructure and Adsorption Property of Bamboo-Based Activated Carbon Fibers Prepared by Liquefaction and Curing

In this study, activated carbon fibers (BACF) were prepared from moso bamboo by phenol liquefaction, spinning, curing, and CO2 activation. The microstructure and porous texture of BACF were investigated by Fourier transform IR spectroscopy, X-ray diffraction, and N2 adsorption at -196°C. The surface area and pore volume increased progressively after activation, and yields were found in the range of 39-59.6%. BACF showed type I isotherms with multimodal pore size distributions in th

Experimental verification of acoustic pseudospin multipoles in a symmetry-broken snowflakelike topological insulator

Topologically protected wave engineering in artificially structured media resides at the frontier of ongoing metamaterials research, which is inspired by quantum mechanics. Acoustic analogs of electronic topological insulators have recently led to a wealth of new opportunities in manipulating sound propagation by means of robust edge mode excitations through analogies drawn to exotic quantum states. A variety of artificial acoustic systems hosting topological edge states have been proposed analogous to the quantum Hall effect, topological insulators, and Floquet topological insulators in electronic systems. However, those systems were characterized by a fixed geometry and a very narrow frequency response, which severely hinders the exploration and design of useful applications. Here we establish acoustic multipolar pseudospin states as an engineering degree of freedom in time-reversal invariant flow-free phononic crystals and develop reconfigurable topological insulators through rotation of their meta-atoms and reshaping of the metamolecules. Specifically, we show how rotation forms man-made snowflakelike molecules, whose topological phase mimics pseudospin-down (pseudospin-up) dipolar and quadrupolar states, which are responsible for a plethora of robust edge confined properties and topological controlled refraction disobeying Snell's law.This work was supported by National Key R&D Program of China (2017YFA0303702), NSFC (Grants No. 11674172, No. 11574148, No. 11474162), Jiangsu Provincial NSF (BK20160018), and Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX17_0020). J.C. acknowledges the support from the European Research Council (ERC) through the Starting Grant 714577 PHONOMETA and from the MINECO through a Ramón y Cajal grant (Grant No. RYC-2015-17156)