One of the key technical challenges before the widespread adoption of proton exchange membrane fuel cells (PEMFCs) is increasing the durability of the platinum catalyst layer to meet a target of 8000 operating hours with only a 10% loss of performance. Carbon corrosion, one of the primary mechanisms of degradation in fuel cells, has attracted attention from researchers interested in solving the durability problem. As such, the development of catalyst supports to avoid this issue has been a focus in recent years, with interest in hydrophobic supports such as highly graphitized carbons.
View Article and Find Full Text PDFHolo-tomographic microscopy (HTM) is a label-free microscopy method reporting the fine changes of a cell's refractive indices (RIs) in three dimensions at high spatial and temporal resolution. By combining HTM with epifluorescence, we demonstrate that mammalian cellular organelles such as lipid droplets (LDs) and mitochondria show specific RI 3D patterns. To go further, we developed a computer-vision strategy using FIJI, CellProfiler3 (CP3), and custom code that allows us to use the fine images obtained by HTM in quantitative approaches.
View Article and Find Full Text PDFThe life history, distribution, and acoustic ecology of the sei whale (Balaenoptera borealis) in the western North Atlantic Ocean remains poorly understood. In this study an array of bottom-mounted recorders captured previously undocumented low frequency 50 to 30-Hz triplet and singlet down sweep vocalizations in close association with signature 82 to 34-Hz sei whale down sweep vocalizations. Spatiotemporal correlations of acoustically tracked sei whales confirm the original vocalizations are produced by sei whales.
View Article and Find Full Text PDFIn melanoma, vascular endothelial growth factor-C (VEGF-C) expression and consequent lymphangiogenesis correlate with metastasis and poor prognosis. VEGF-C also promotes tumor immunosuppression, suggesting that lymphangiogenesis inhibitors may be clinically useful in combination with immunotherapy. We addressed this concept in mouse melanoma models with VEGF receptor-3 (VEGFR-3)-blocking antibodies and unexpectedly found that VEGF-C signaling enhanced rather than suppressed the response to immunotherapy.
View Article and Find Full Text PDFRationale: Spirometry plays a major role in the diagnosis and assessment of severity of lung disease. Determining which lung function values are normal and which are below the lower limit of normal depends on reference equations derived from an appropriate population.
Objectives: The purpose of this study was to derive spirometric reference equations for the Canadian population.
Low frequency (<100 Hz) downsweep vocalizations were repeatedly recorded from ocean gliders east of Cape Cod, MA in May 2005. To identify the species responsible for this call, arrays of acoustic recorders were deployed in this same area during 2006 and 2007. 70 h of collocated visual observations at the center of each array were used to compare the localized occurrence of this call to the occurrence of three baleen whale species: right, humpback, and sei whales.
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