(C) 2011 American Institute of Physics. [doi:10.1063/1.3562519]“
“In many angiosperm species, populations are reproductively subdivided into distinct sexual morphs including females, males and hermaphrodites. Sexual polymorphism
is maintained by frequency-dependent selection, leading to predictable sex ratios at equilibrium. Charles Darwin devoted much of his book ‘The Different Forms of Flowers on Plants of the Same Species’ (1877) to investigating plant sexual polymorphisms and laid the foundation for many problems addressed today by integrating selleck theory with empirical studies of the demography and genetics of populations. Here, we summarize our recent work on the ecological and genetic mechanisms influencing variation in sex ratios and their implications for evolutionary transitions among sexual systems. We present the results of a survey of sex ratios from 126 species from 47 angiosperm
families and then address two general problems using examples from diverse angiosperm taxa: (i) the mechanisms governing biased sex ratios in dioecious species; (ii) the origins and maintenance of populations composed of females, males and hermaphrodites. Several themes are emphasized, including the importance of non-equilibrium conditions, the role of life history and demography in affecting sex ratios, the value of theory for modelling the dynamics of sex ratio variation, and the utility of genetic markers for investigating evolutionary processes in sexually polymorphic
“Oligoethers containing electroactive carbazolyl, IWR-1-endo ic95 indolyl or 2-phenylindolyl fragments were synthesized and characterized by NMR spectroscopy, elemental analysis and gel permeation chromatography. The oligomers represent ML323 Ubiquitin inhibitor amorphous materials of high thermal stability with glass transition temperatures of 107-161 degrees C. The electron photoemission spectra of layers of the synthesized oligomers showed ionization potentials of 5.9-5.95 eV. Some of the derivatives were tested as host materials in phosphorescent OLEDs with iridium(III) [bis(4,6-difluorophenyl)-pyridinato-N,C2']picolinate as the guest. The device based on oligomer containing carbazolyl fragments exhibited the best overall performance with a turn-on voltage of 3.5 V, maximum power efficiency of 4.1 lm/W and maximum brightness of 937 cd/m(2). (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 908-913, 2011″
“We report upon a theoretical study of collective magnonic modes in pairs of magnetic nano-elements with quasi-uniform magnetization. The mode spectrum and character are numerically computed for an individual isolated nano-element and then used to analytically calculate the splitting of the modes due to the inter-element magneto-dipole interaction.