More than one way to see it: Individual heuristics in avian visual computation

Comparative pattern learning experiments investigate how different species find regularities in sensory input, providing insights into cognitive processing in humans and other animals. Past research has focused either on one species’ ability to process pattern classes or different species’ performance in recognizing the same pattern, with little attention to individual and species-specific heuristics and decision strategies. We trained and tested two bird species, pigeons (Columba livia) and kea (Nestor notabilis, a parrot species), on visual patterns using touch-screen technology. Patterns were composed of several abstract elements and had varying degrees of structural complexity. We developed a model selection paradigm, based on regular expressions, that allowed us to reconstruct the specific decision strategies and cognitive heuristics adopted by a given individual in our task. Individual birds showed considerable differences in the number, type and heterogeneity of heuristic strategies adopted. Birds’ choices also exhibited consistent species-level differences. Kea adopted effective heuristic strategies, based on matching learned bigrams to stimulus edges. Individual pigeons, in contrast, adopted an idiosyncratic mix of strategies that included local transition probabilities and global string similarity. Although performance was above chance and quite high for kea, no individual of either species provided clear evidence of learning exactly the rule used to generate the training stimuli. Our results show that similar behavioral outcomes can be achieved using dramatically different strategies and highlight the dangers of combining multiple individuals in a group analysis. These findings, and our general approach, have implications for the design of future pattern learning experiments, and the interpretation of comparative cognition research more generally

Delay-induced multistability near a global bifurcation

We study the effect of a time-delayed feedback within a generic model for a saddle-node bifurcation on a limit cycle. Without delay the only attractor below this global bifurcation is a stable node. Delay renders the phase space infinite-dimensional and creates multistability of periodic orbits and the fixed point. Homoclinic bifurcations, period-doubling and saddle-node bifurcations of limit cycles are found in accordance with Shilnikov's theorems.Comment: Int. J. Bif. Chaos (2007), in prin

CD97 (CD97 molecule)

Review on CD97 (CD97 molecule), with data on DNA, on the protein encoded, and where the gene is implicated

Turning product design into public service

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.Statement of responsibility on t.p. reads: Laura E. Aust, Zachary W. Rose, Ariadne G. Smith, Amrita Saigal. Each student submitted a title page and vita. Cataloged from PDF version of thesis.Includes bibliographical references (p. 87-89 ([i.e. p. [99]-[101])).Every mechanical engineering student at MIT takes the same courses: 2.009 being one of them. In our capstone product design course at MIT, most students glean an incredible amount from their teams, mentors, and projects, then focus their efforts on slightly more pressing issues, such as graduating and finding jobs and grad school. But what if the project you found was bigger than just a course, and had the potential of improving the lives of those less fortunate than you? The Komera project creates affordable sanitary protection for women in developing countries from the locally available and all-natural fiber from banana plants. In doing so, the initiative not only empowers girls by allowing them to attend school during their periods, but also creates employment and income within their communities. Our first initial iterations of the machine to fabricate pads were created in 2.009. Previous mechanical solutions to this problem are inefficient and labor-intensive. With our prototype, we seek to reduce the labor involved and increase pad output by twofold. However, we didn't want out work to stop there. Over the course of the semester, we continued to expand the Komera project twofold: by working on the mechanical design of the product and by expanding our scope to transform the product into a public service initiative. This thesis discusses the trials and tribulations of both directions. We explore the differences and challenges in designing for the developing world within a 1 st-world product design context - paying attention to manufacturing, materials, cost, and usability. We also offer a guide through the creation of an initiative: how we took a product and turned it into an IDEAS-winning public service project. It has been an incredibly rewarding experience for us, and we hope that we can inspire others to work on international development products as well.by Laura E. Aust ... [et al.].S.B

Czech Social Reform/Non-reform: Routes, Actors and Problems

In this contribution, the author first considers the characteristics of the Czechoslovak communist welfare state and its theoretical alternatives. Throughout the reform process, dependency on both corporatist and socialist regimes won out, while residualist efforts were promoted in the beginning, but were later held back. The author then considers the possible actors involved in social reforms. In this respect, when proceeding from a general to a more concrete level, thought should first be devoted to the social classes and their ideologies, and second to political parties and their leaders. The author goes on to summarise the particular problems and traps in individual sections of the Czech social system. While no objection to decent standards of social protection and health care could be raised, the poor efficiency of their achievement should evoke concern. The author concludes by reflecting on the possible specificities of Czech social reform in comparison with the other countries undergoing reform and the EU. The current lethargy of the Czech welfare system corresponds to a “frozen edifice”, just as in most Western countries. However, such stagnation is apparently acceptable to both the politicians (who mask it in reformist rhetoric) and the population (which learned to master taking advantage of the generous welfare state) and thus is basically sustainable in the long run.http://deepblue.lib.umich.edu/bitstream/2027.42/40037/3/wp651.pd