Characterization of an endothelial protein in the developing rabbit kidney

A new protein (EnPo 1 antigen) abundant on endothelial cells and glomerular podocytes has been characterized by means of the mouse monoclonal antibody EnPo 1. Following electrophoretical separation of rabbit kidney homogenates EnPo 1 recognized a protein with a molecular weight of 110 kDa and an isoelectric point of 5.9 in Western blots. Using immunohistological techniques, the EnPo 1 antigen has been localized in high concentrations on glomerular podocytes of different developmental stages. Furthermore, the EnPo 1 antigen was expressed on endothelial cells of all adult rabbit organs tested so far. Detailed analysis of neonatal rabbit kidney revealed the abundance of EnPo 1 antigen on both differentiated vessels as well as on immature endothelial cells and endothelium of the microvasculature. Thus, for the first time a marker for in situ investigations of angiogenic processes within the mammalian kidney is available. Analysis of kidney cryosections by confocal laser scan microscopy revealed a direct connection between mature and differentiating vessels in the outer kidney cortex. Furthermore, two differentially organized cell populations discriminated by their EnPo 1 binding pattern were localized in the embryonic renal cortex. Morphologically, these cells were not distinguishable from other mesenchymal cells.     

Bionic Photovoltaic Panels Bio-Inspired by Green Leaves

In strong solar light, silicon solar panels can heat up by 70℃ and, thereby, loose approximately one third of their efficiencyfor electricity generation. Leaf structures of plants on the other hand, have developed a series of technological adaptations,which allow them to limit their temperature to 40-45℃ in full sunlight, even if water evaporation is suppressed. This is accomplishedby several strategies such as limitation of leaf size, optimization of aerodynamics in wind, limitation of absorbedsolar energy only to the useful fraction of radiation and by efficient thermal emission. Optical and infrared thermographicmeasurements under a solar simulator and in a streaming channel were used to investigate the corresponding properties of leavesand to identify suitable bionic model systems. Experiments started with the serrated structure of ordinary green leaves distributedover typical twig structures and finally identified the Australian palm tree Licuala ramsayi as a more useful bionic model. Itcombines a large area for solar energy harvesting with optimized aerodynamic properties for cooling and is able to restructureitself as a protection against strong winds. The bionic models, which were constructed and built, are analyzed and discussed.