Vascular endothelial growth factor-D (VEGF-D) promotes angiogenesis, lymphangiogenesis and metastatic spread via the lymphatics, however, the mode of VEGF-D action (e.g. paracrine vs. autocrine) was unknown. We analyzed VEGF-D action in human tumors and a mouse model of metastasis. VEGF-D was localized in tumor cells and endothelium in human non-small cell lung carcinoma and breast ductal carcinoma in situ. Tumor vessels positive for VEGF-D were also positive for its receptors, VEGF receptor-2 (VEGFR-2) and/or VEGFR-3 but negative for VEGF-D mRNA, indicating that VEGF-D is secreted by tumor cells and subsequently associates with endothelium via receptor-mediated uptake. The mature form of VEGF-D was detected in tumors demonstrating that VEGF-D is proteolytically processed and bioactive. In a mouse model of metastasis, VEGF-D synthesized in tumor cells became localized on the endothelium and thereby promoted metastatic spread. These data indicate that VEGF-D promotes tumor angiogenesis, lymphangiogenesis and metastatic spread by a paracrine mechanism.

Fluorosilicone polymers combine the properties of both fluorocarbons and siloxanes, yielding materials with unique properties. Novel crosslinked fluorosilicone polymers were synthesized by grafting diisocyanate-terminated polydimethylsiloxane (PDMS) to hydroxyl-functionalized fluoropolymers of poly(tetrafluoroethylene-co-vinyl acetate-co-vinyl alcohol) (PTFE-VAc-VA), as confirmed by elemental bulk and surface analysis. The fluorosilicone polymers containing 34 mol% of TFE were thermally stable with a degradation temperature of 267 °C. Fluorosilicone films were found to be more hydrophobic than the parent, non-grafted fluoropolymers; dynamic advancing and receding water contact angles for PTFE-co-VAc-co-VA-g-PDMS were 104° ± 1° and 61° ± 1°, respectively, whereas for PTFE-co-VAc they were 90° ± 2° and 59° ± 2°. The combined properties of thermal stability and hydrophobicity suggest that these fluorosilicones may be useful for coating and paint applications.Key words: fluoropolymers, fluorosilicone, polydimethylsiloxane, supercritical carbon dioxide.

Summary The energy intensity of fuel‐based lighting is substantial given the paltry levels of lighting service, poor economic outcomes, and exposure to public health risks for users throughout the developing world. There is a great opportunity to reduce fossil energy consumption (and mitigate greenhouse gas emissions) while improving public health and economic outcomes for the poor by encouraging upgrading from fuel‐based to rechargeable light‐emitting diode (LED) lighting. However, switching to efficient lighting requires up‐front investments of energy for manufacturing. This study explores life cycle energy performance in the market for modern off‐grid lighting (OGL) products in Sub‐Saharan Africa and introduces a new metric, life cycle efficacy, which facilitates comparisons and analysis of life cycle energy performance (light output per unit of embodied plus use‐phase energy consumption) for lighting technology systems. Combining field insights on technology adoption dynamics with embodied energy estimates for a range of products available in 2012 shows that OGL energy “debts” are “paid back” in 20 to 50 days (substantially faster than kilowatt‐scale grid‐connected solar electricity systems) with energy return on investment ratios from 10 to 40. This stems from greatly improved life cycle efficacy for off‐grid LED lighting (∼20 lumens/watt [lm/W]), compared to fuel‐based lighting (∼0.04 lumens/W). Life cycle benefits—not only energy, but also economic and health benefits—depend strongly on product service lifetime (related to quality) and fuel displacement fraction (related to performance). OGL life cycle efficacy increases from longer lifetime and/or improved LED source efficacy lead to better quality and less‐expensive lighting available in the developing world with lower energy use than the fuel‐based incumbent technology.

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