Apart from an exceptional experimental study already published in 1720, it started with observational field studies of scatter hoarding birds in the 1940s. Driven by a general interest in birds, several ornithologists made large-scale studies of hoarding behaviour
in species such as nutcrackers and boreal titmice. NCT-501 in vivo Scatter hoarding birds seem to remember caching locations accurately, and it was shown in the 1960s that successful retrieval is dependent on a specific part of the brain, the hippocampus. The study of scatter hoarding, spatial memory and the hippocampus has since then developed into a study system for evolutionary studies of spatial memory. In 1978, a game theoretical paper started the era of modern studies by establishing that a recovery advantage is necessary for individual hoarders for the evolution of a hoarding strategy. The same year, a combined theoretical and empirical study on scatter hoarding squirrels investigated how caches should be spaced out in order to minimize cache loss, a phenomenon sometimes called optimal cache density theory. Since
then, the scatter hoarding paradigm has branched into a number of different fields: (i) theoretical and empirical studies of the evolution of hoarding, (ii) field studies with modern sampling methods, (iii) studies of the precise nature of the caching memory, (iv) a variety of studies of caching selleck chemical memory and its relationship to the hippocampus. Scatter hoarding buy AG-881 has also been the subject of studies of (v) coevolution between scatter hoarding animals and the plants that are dispersed by these.”
“The aim of
this study was to examine the properties of polyester nanofibers produced by the electro-spinning method. Solvent-spun nanofibers with different concentrations of poly(ethylene terephthalate) (13,16, and 20 wt %) were produced. The morphology and surface energy of the fibers were analyzed by scanning electron microscopy and contact angle measurements. Tensile testing, dynamic mechanical analysis, and differential scanning calorimetry were carried out to characterize the thermal and mechanical properties. X-ray diffraction and attenuated total reflection Fourier transform infrared spectroscopy tests were performed to analyze the microstructural properties. The results show that a nanoweb of the 16 wt % solution had better mechanical and thermal behaviors because of the increased molecular orientation in the amorphous structure and the narrower fiber diameter distribution in the web. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 120: 759-769, 2011″
“The photodetachment of H- near a metal surface covered with a dielectric thin film has been studied using the closed orbit theory. The results show that the thickness and the dielectric constant of the dielectric thin film have great effect on the photodetachment of negative ion.