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References Andrén , H. 1994 . Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a

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Abstract  

An Auger event triggered by electron-capture (EC) decay of 57 Co incorporated in a chelate molecule results in the loss of an average of 5 electrons. During subsequent charge neutralization, the molecule acquires >50 eV of excitation energy. Only molecules having a large -electron system were found to escape fragmentation. The fate of the molecule was followed by the 14.4 keV Mössbauer emission which occurs 10-7 second after the EC event. For a conjugated molecule to survive fragmentation, it should be able to disperse its energy in a time interval shorter than the period of atomic vibrations. We had proposed earlier that p-electrons undergo collective excitation and that the plasmon decays in <10-14 second accompanied by ejection of an electron leaving the molecule unscathed. Intermolecular energy transfer is not important and even an isolated molecule of 57 Co(II) phthalocyanine encapsulated in a zeolite supercage escapes fragmentation following an Auger event. Our model for rapid disposal of large excitation energy receives additional support from recent reports of single or mulitphoton plasmon excitation (20 eV) in an isolated C60 and C70 fullerene molecule followed by ejection of a single energetic electron leaving the molecule intact.

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Community Ecology
Authors: J. Herrmann, U. Kormann, C. Schüepp, Y. Stocker, F. Herzog, and M. Entling

fragmentation, population density, and prey availability on body condition of two orb-weaving spiders. Ecol. Entomol. 36: 680–685. Entling M.H. Contrasting effects of habitat fragmentation

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Yields of Fe3+ from aerated and deaerated solutions of ferrous sulfate irradiated with high energy carbon or neon ions are shown to be consistent with current theoretical models of radiation chemistry, if fragmentation of the incident ion is taken into account. For argon, the observed yields are higher than predicted.

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This study applies a method of author co-citation analysis to examine the intellectual structure of political communication study. Fifty one influential authors were selected from active members of the Political Communication Divisions of the International Communication Association (ICA), the National Communication Association (NCA), and the American Political Science Association (APSA). The results of the multidimensional scaling analysis and cluster analysis of these 51 selected authors' co-citation patterns show that intellectual fragmentation exists in political communication research; scholars with different academic backgrounds exhibit specialties using particular research approaches to study certain subjects in the field; scholars do not have much information exchange, and thus they are intellectually separate and confined within the boundaries of each fragment. The findings of this quantitative study complements and cross-validates the assessment made by other traditional qualitative reviews about the field.

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This paper deals with the possible existence of political budget cycles (PBCs) within the European Union (EU). I use panel data for 28 EU countries from 1995 to 2016 and provide estimates based on dynamic panel regressions. I employ a system-GMM estimator complemented by the Principal Component Analysis (PCA) to limit the number of instruments. The specifications include structural budget balances related to the potential GDP, thereby limiting the initial endogeneity. These measures capture the true motivation behind fiscal policies. The results suggest that the EU member states exhibit PBCs: (i) the intervention occurs in the year before elections and (ii) the structural budget balance to the potential GDP ratio is lower by −0.41 percentage points a year before elections. In addition, I have investigated the EU fragmentation in terms of the PBCs and selected 8 countries’ characteristics correlating to the existence of these cycles. These include lower GDP per capita, post-communist background, low tax burden, high perceived corruption, low levels of media freedom and internet usage, lower number of directly voted-in legislative officials, and a low parliamentary voter turnout.

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The relationships between frugivorous animals and plants are of vital importance particularly in tropical forests. The way species interact and how they are organized within interaction networks could be determined by their ecological and morphological characteristics. This study evaluates the hypothesis that the topological position of species within an interaction network is determined by their degree of frugivory, body size, and abundance. Thus, we constructed the frugivory network between birds and plants in a rainforest fragment in northwestern Colombia. The position of the species within the network was calculated based on three centrality measures (degree, betweenness, and closeness), and its association with relative abundance, degree of frugivory, and body size of each bird species was evaluated by means of a generalized linear model. We found that the species that were most abundant and had the smallest body size had central positions in the interaction network. This pattern is contrary to what has been observed in pristine forests, where species with large body size are more important for network stability. Our results suggest that forest fragmentation modifies the roles of species within the network structure, in part, due to changes in the makeup of the original frugivore community. The information presented may be useful to evaluate the effects of the loss of species as a result of anthropic actions, with the aim of generating ecosystem restoration strategies.

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Chiarello, A. G. 1999. Effects of fragmentation of the Atlantic forest on mammal communities in south-eastern Brazil. Biol. Conserv. 89: 71–82. Chiarello A. G. Effects of fragmentation

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ESR spectra for -irradiated at 77 K solutions /0.02–16%/ of tetramethylurea /TMU/ in CFCl3 and Freon-113 have been studied. TMU+. radical cations radiolytically produced in dilute solutions have been shown to undergo intramolecular hydrogen transfer upon photobleaching resulting in CH2N= type radical. Evidence for intermolecular proton transfer in TMU+. radical cations after annealing to phase transition temperature /110–120 K/ in Freon-113 was obtained. Primary radical cations of TMU+. at their ground state take part in ion-molecular reaction via proton transfer. Molecular cations in their excited states may undergo fragmentation producing Me2N radicals, which were trapped in liquid phase by t-BuNO as a spin trap.

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: habitat fragmentation affects forest specialists and generalists differently . For. Ecol. Manage. 262 : 1863 – 1871 . Brunet , J. , P. De Frenne , E. Holmström , and M.L. Mayr

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