196,123 research outputs found
evoludolab/IBS-DSCG: v1.0 PNAS 2021
No full text<p>Supporting source code for simulation results reported in Hauert, C. & Doebeli, M. (2021) <em>Spatial social dilemmas promote diversity</em>, Proc. Natl. Acad. Sci. USA 118 (42) e2105252118 doi: <a href="https://doi.org/10.1073/pnas.2105252118">10.1073/pnas.2105252118</a>.</p>
Measurement of the lifetime of photo-generated free carriers in Si-Ge waveguides
No full textThe carrier lifetime in SiGe planar waveguides with Si cladding was measured with a pump-and-probe technique, using an ultrashort 810 nm laser pulse and a CW 1.55 mu m probe, as a function of layer thickness d and Ge concentration x. The measured lifetimes are in the range of 20-90 ns. The obtained interface recombination velocity S is a growing function of both d and x, taking values in the range from 300 to 4000 cm/s
Adaptive speciation: Epilogue
No full textUnraveling the origin of biodiversity is fundamental for understanding our biosphere. This book clarifies how adaptive processes, rather than geographic isolation, can cause speciation. Adaptive speciation occurs when biological interactions induce disruptive selection and the evolution of assortative mating, thus triggering the splitting of lineages. Internationally recognized leaders in the field explain exciting developments in modeling speciation, together with celebrated examples of rapid speciation by natural selection. Written for students and researchers in biology, physics, and mathematics, this book is a ground-breaking treatment of modern speciation science
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Evolution of phenotypic clusters through competition and local adaptation along an environmental gradient
No full textWe have analyzed the evolution of a quantitative trait in populations that are spatially extended along an environmental gradient, with gene flow between nearby locations. In the absence of competition, there is stabilizing selection toward a locally best-adapted trait that changes gradually along the gradient. According to traditional ideas, gradual spatial variation in environmental conditions is expected to lead to gradual variation in the evolved trait. A contrasting possibility is that the trait distribution instead breaks up into discrete clusters. Doebeli and Dieckmann (2003) argued that competition acting locally in trait space and geographical space can promote such clustering. We have investigated this possibility using deterministic population dynamics for asexual populations, analyzing our model numerically and through an analytical approximation. We examined how the evolution of clusters is affected by the shape of competition kernels, by the presence of Allee effects, and by the strength of gene flow along the gradient. For certain parameter ranges clustering was a robust outcome, and for other ranges there was no clustering. Our analysis shows that the shape of competition kernels is important for clustering: the sign structure of the Fourier transform of a competition kernel determines whether the kernel promotes clustering. Also, we found that Allee effects promote clustering, whereas gene flow can have a counteracting influence. In line with earlier findings, we could demonstrate that phenotypic clustering was favored by gradients of intermediate slope
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