964,503 research outputs found
Neuroscience: who are we?
Writing for the interested public, Gazzaniga marshals recent findings from neuroscience to demonstrate the crucial roles of social interactions and context in the evolution of human mind
The roles of ram-pressure stripping and minor mergers in evolution of galaxies
We investigate environmental effects on evolution of bright cluster galaxies
in a Lambda-dominated cold dark matter universe using a combination of
dissipationless N-body simulations and a semi-analytic galaxy formation model.
We incorporate effects of ram-pressure stripping (RPS) and minor merger-induced
small starburst (minor burst) into our model. By considering minor burst,
observed morphology-radius relation is successfully reproduced. When we do not
consider minor burst, the RPS hardly increases the intermediate B/T population.
In addition, the RPS and minor burst are not important for colours or star
formation rates of galaxies in the cluster core if star formation time-scale is
properly chosen, because the star formation is sufficiently suppressed by
consumption of the cold gas. We also find that SF in bulge-dominated galaxies
is mainly terminated by starburst induced by major mergers in all environments.Comment: To appear in the proceedings of IAU colloq. No. 195, "Outskirts of
Galaxy Clusters: intense life in the suburbs", Torino, 12-16 March 2004, 5
pages, 2 figures, uses IAU macr
The evolution of parental sex roles
In many animals, parents provide care to their offspring, such as building nests, or feeding the young. Species differ considerably in how parental care is distributed between the male and the female parent. In my PhD thesis, I shed new light on the question how the baffling diversity of parental care patterns 1,101 bird species, in order to find out whether ecological factors (such as nest type) or life-history characteristics (such as body size) explain when species exhibit uniparental or biparental care. Although I could identify some significant factors (e.g., breeding in a colony), my main conclusion is that many hypotheses proposed in the literature are not confirmed by the data. Second, I constructed theoretical models in order to gain a better understanding of how and why diverse parental care patterns emerge in the course of evolution. I analysed these models by means of individual-based simulations, which are more versatile and based on fewer simplifying assumptions than standard mathematical approaches. My simulations provide surprising new insights. During evolution, regularly âcare polymorphismsâ emerge where very different care strategies coexist in males and/or females. Although these polymorphisms may disappear again after a brief period of time, I could show that they are often decisive for the course and outcome of evolution. This finding has important implications for the evolution of parental sex roles, and it necessitates a reconsideration of many seemingly well-established predictions of sex role theory
Campus Art Museums in the 21st Century: A Conversation
In the summer of 2012, the authors of this study brought together a group of campus art museum directors and outside experts to 'think out loud' about the changes already occurring at campus museums and where new opportunities and roles may be emerging. We hope the resulting paper will further the field's larger, continuing exploration of its roles and potentials through dialogue, research, and experimentation -- an exploration that contributes to the continued healthy evolution of campus art museum practice
Galactic chemical evolution
We analyze the evolution of oxygen abundance radial gradients resulting from our chemical evolution models calculated with different prescriptions for the star formation rate (SFR) and for the gas infall rate, in order to assess their respective roles in shaping gradients. We also compare with cosmological simulations and confront all with recent observational datasets, in particular with abundances inferred from planetary nebulae. We demonstrate the critical importance in isolating the specific radial range over which a gradient is measured, in order for their temporal evolution to be useful indicators of disk growth with redshift
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