Most climate change studies to date have focused on individuals or species populations, rather

than the higher levels of organization (i. e. communities, food webs, ecosystems). We propose that an understanding of the connections between these different levels, which are all ultimately based on individuals, can help to develop a more coherent theoretical framework based on metabolic scaling, foraging theory and ecological stoichiometry, to predict the ecological consequences of climate change. For instance, individual basal metabolic rate scales with body size (which also constrains food web structure and dynamics) and temperature (which determines many ecosystem processes and key aspects of foraging behaviour). selleck products In addition, increasing atmospheric CO(2) is predicted to alter molar CNP ratios of detrital inputs, which could lead to profound shifts in the stoichiometry of elemental fluxes between consumers and resources at the base of the foodweb. The different components of climate change (e. g. temperature, hydrology and atmospheric composition) not only affect multiple levels of biological organization, but they may also interact with the many other stressors to which fresh waters are exposed, and future research needs to address

these potentially important synergies.”
“One of the most important challenges selleck chemicals llc in polyurethane (PU) science is characterization of foam morphologies, which provides information to help understand material properties and improve synthesis conditions. Atomic force microscopy (AFM) is a very useful technique to obtain such information. A key challenge is to apply this technique to PU foams without destroying their cell structure. In this article, we describe the development of a methodology to characterize check details different types of PU foams using AFM while keeping the foam cells intact. Epoxy resin was used to impregnate the foams and was cured afterwards. Smooth surfaces were created using a micro-tome

to minimize topographic effects during AFM examination. Phase information was obtained on the PU matrix and differentiated from the epoxy in AFM. This technique is demonstrated using several different foams including a flexible foam, two different elastomeric foams, and a rigid foam nanocomposite. Comparison with compression techniques reveals that the proposed method does not modify foam morphology. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 2644-2651, 2011″
“In this paper we present a magnetic study of Co(1-x)Bi(x)Fe(2)O(4) nanoparticles obtained by applying magnetic fields up to 14 T and for temperatures in the range of 5 to 340 K. Hysteresis loops yield a saturation magnetization (M(s)), coercive field (H(c)), and remanent magnetization (M(r)) that vary significantly with temperature and bismuth content.