BACKGROUND AND PURPOSE Braided self-expandable stents and flow diverters of uniform construction may develop zones of heterogeneous porosity in vivo. Unwanted stenoses may also occur at the extremities of the device. We studied these phenomena in dedicated benchtop experiments. MATERIALS AND METHODS Five braided devices of decreasing porosity were studied. To simulate discrepancies in diamete...

Ecological phenomena are evident over a broad spectrum of space and time scales. Ecotones, being defined as zones of transition between adjacent ecological systems, also must occur over an equally broad spectrum of space and time scales. Scale-dependent constraints influence ecological phenomena and resulting zones of transition; however, in traditional ecotone studies little treatment has been...

in order to investigate the role of multi-wall carbon nanotubes (mwcnts) on fracture mechanism of epoxy nanocomposites, a series of tensile standard specimens reinforced with different carbon nanotube contents (0, 0.3, 0.6 and 1 wt%) were produced. the fracture surfaces of the produced nanocomposites were evaluated using scanning electron microscope (sem). the results show that the surface frac...

This paper presents an automatic method for detecting transition zones based on multiresolution spectral analysis (MRS). The MRS is calculated over several Fast Fourier Transforms (FFT) of different length. It can provide a higher temporal accuracy in the upper spectral region and a better frequency resolution in the lower spectral range. We showcase the importance of this tool by attempting an...

This study is an extension of our last researches about the detection of transition zones based on multiresolution spectral analysis (MRS). In this paper we present the fourth step for the realization of an automatic system for Tunisian Dialect segmentation and analysis. The MRS is calculated over several Fast Fourier Transforms (FFT) of different length. It can provide a higher temporal accura...

Bone morphogenetic protein (BMP) signaling is known to suppress oncogenesis in the small and large intestine of mice and humans. We examined the role of Bmpr1a signaling in the stomach. On conditional inactivation of Bmpr1a, mice developed neoplastic lesions specifically in the squamocolumnar and gastrointestinal transition zones. We hypothesized that the regulation of epithelial cell fate may ...

This study uses the amphibian species of the Mediterranean basin to develop a consistent procedure based on fuzzy sets with which biogeographic regions and biotic transition zones can be objectively detected and reliably mapped. Biogeographical regionalizations are abstractions of the geographical organization of life on Earth that provide frameworks for cataloguing species and ecosystems, for ...