Archive for July, 2008
Tenements and Flesh: Poverty writing the Body in Tillie Olsen’s Yonnondio
Olsens Yonnondio declares that the body is a marker of poverty a body suffers from, desires regardless of, and effects and is affected by poverty. The female body experiences this marking in a profoundly unique way through childbirth and rearing, relegation to the home and domestic work, and subjugation to men, especially husbands. As a result, the female body inhabits a critical space for understanding the effects of poverty; as Mara Faulkner reminds us, Olsen herself claims that telling the truth about ones body is a necessary, freeing subject for the woman writer (150). Through both material and metaphoric descriptions of Annas sexualized body, her milk-filled breasts especially, Olsen intimately acquaints her readers with the reality of impoverished American life.
Study of Monomer Droplets in Miniemulsions
Miniemulsion technology offers possible applications such as encapsulation of pigments, oils, and polymers, and polymerization of highly water-insoluble monomers not possible via conventional emulsion polymerization. Fundamental understanding of miniemulsions has been hindered by ignorance of their droplet size distribution (DSD). In this work, the droplet size and size distribution of miniemulsions have been characterized using, with adaptation, particle sizing techniques such as capillary hydrodynamic fractionation (CHDF), acoustic attenuation spectroscopy (AAS), surfactant titration, dynamic light scattering (DLS), and microscopy. › Continue reading
HTN-MAKER: Learning HTNs with Minimal Additional Knowledge Engineering Required
We describe HTN-MAKER, an algorithm for learning hierarchical planning knowledge in the form of decomposition methods for Hierarchical Task Networks (HTNs). HTN-MAKER takes as input the initial states from a set of classical planning problems in a planning domain and solutions to those problems, as well as a set of semantically-annotated tasks to be accomplished. The algorithm analyzes this semantic information in order to determine which portions of the input plans accomplish a particular task and constructs HTN methods based on those analyses.Our theoretical results show that HTN-MAKER is sound and complete. We also present a formalism for a class of planning problems that are more expressive than classical planning. These planning problems can be represented as HTN planning problems. We show that the methods learned by HTN-MAKER enable an HTN planner to solve those problems. Our experiments confirm the theoretical results and demonstrate convergence in three well-known planning domains toward a set of HTN methods that can be used to solve nearly any problem expressible as a classical planning problem in that domain, relative to a set of goals.
Sex Differences During Development in NeuN Labeling of the MPN mag of Syrian Hamsters
Sexual behavior is critical for ensuring the survival of many species. To date, male sex behavior in all vertebrate species is regulated by the medial preoptic area (MPOA). In the Syrian hamster, male mating behavior is regulated by a subdivision of the MPOA, the magnocellular division of the medial preoptic nucleus (MPNmag). Lesions of the MPNmag eliminate male mating behavior. Adult males have significantly greater number and density of neurons in this nucleus compared to females. Our lab has shown that the MPN mag becomes sexually dimorphic in the total number of cells between postnatal days 5 and 10. Yet, it is not known whether these differences in cell number reflect differences in neuron number or another cell type. NeuN is a protein found exclusively in neurons. The goal of this experiment was to determine if there is a sex difference in the number of neurons in the MPN mag on postnatal day 5 or 10 by examining the number of NeuN labeled cells in the MPN mag.
Male and female hamsters were perfused 5 or 10 days after birth. Brains were removed, cut into 40 um sections on a freezing microtome, mounted on slides and stored at -20C until labeled for NeuN using immunocytochemistry. The number of neurons was determined using the particle counting program in ImageJ. Our data suggests that sex differences in neuron number are present as early as postnatal day 5.