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    Primate Bone Histomorphology and its Relationship to Biomechanical Forces
    (1994) Paine, Robert R.
    Observations of nonhuman primate long bone microanatomy were undertaken with the explicit goal of recording intra- and interspecific variation in the percentage of osteonal bone. One-hundred and eight specimens with age, sex, body size, and positional behavior data representing 7 species (Galago seneqalensis, Otolemur crassicaudatus, Macaca fascicularis, Macaca mulatta, Macaca arctoides, Erythrocebus patas, and Cercopithecus aethiops) were examined. Humeral and femoral shafts were examined histologically at the proximal, midshaft, and distal cross sections. Furthermore, the humeral and femoral midshaft sections were histologically examined at the anterior, posterior, medial, and lateral quadrants. Each cross section and quadrant were read specifically for percentages of osteonal bone. Data on cortical bone area and cortical thickness were also recorded for each section. Descriptive statistics, analysis of variance, and Model II regression (maximum likelihood estimation) were used to test for intra- and interspecific variation in osteonal bone for this population of primates. In general, several points concerning primate skeletal microanatomy have been revealed: 1) humeral and femoral microanatomy do not mirror each other in osteonal pattern, suggesting that different factors affect the bone microstructure of these limb bones, 2) primate species with different positional behavior express different distributions of osteonal bone and these differences reflect body size and mechanical usage, 3) after sexual maturation age does not affect intraspecific variations in the percentage of osteonal bone, 4) osteon area scales positively allometrically on body size (cortical area) suggesting that the rate of osteon area increases faster than the rate of increase in body size among primate species. Other conclusions have been drawn from this study, the most important point of which is that mechanical loading plays a large role in stimulating secondary osteon formation and that osteonal bone distribution reflects positional behavior and body size. This has profound implications for how future primate histological research can be conducted. The results of this study also have implications for the application of histological analysis to extinct primate specimens. Overall, this information will give primatologists additional important tools to be used in examining skeletal form as it relates to function in both living and extant primate species.
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    A Category of Sample Spaces
    (1971) Collins, Walter Robert
  • Publication
    Natural Selection and the Syntax of Clausal Complementation
    (2009-09-01) Moulton, Keir
    This dissertation examines the syntax and semantics of clausal complements. It identifies semantic underpinnings for some syntactic properties of the arguments of propositional attitude verbs. The way clausal arguments compose with their embedding predicates is not uniform and semantic differences emerge from the syntactic context clausal arguments appear in. Three case studies are taken up: clausal arguments of nouns, dislocated clausal arguments (sentential subjects and topics), and infinitival complements with overt subjects (AcI constructions). Chapter Two assembles evidence to support Stowell’s (1981) claim that the clausal complements of nouns are modifiers. It is shown that the clausal complements of nouns behave like adjuncts in their ability to bleed condition C (Kuno 2004 and Jacobson 2003, and explored here further). The compositional strategy used to compose attitude nouns with their arguments, following Kratzer (2006), is shown to account for this behavior and to be commensurate with observations made by Grimshaw (1990). I then show how the modifier status of clausal complements of nouns is determined by the way in which nominals are formed from clause-taking verbs. Chapter Three examines another complementation strategy, found with fronted clauses. New data from binding is provided in support of Koster’s (1978) hypothesis that clauses do not move. Specifically, fronted clauses fail to show the effects of syntactic reconstruction. An analysis, making crucial use of de re attitude ascription, is offered to account for ‘apparent’ binding into fronted clauses. Chapter Four makes the case for enriching the meanings of clausal complements. By examining some new patterns with accusative with infinitive (AcI) constructions (such as I see him to be a fool), I argue for decomposing certain doxastic attitude verbs, putting the introduction of alternatives into the complement. Here too the role of de re attitude ascription is shown to play a crucial role. It is argued that AcI constructions involve de re attitude ascription, with added constraints (determined by the lexical content of the embedding verb) on the nature of the Acquaintance Relation (Kaplan 1968, Lewis 1979). Several predictions about the kinds of verbs that can participate in AcI are borne out.
  • Publication
    Management of Target-Tracking Sensor Networks
    (2009-09-01) Hadi, Khaled
    Target tracking has emerged as an important application of sensor networks. There are two subproblems inherent to target tracking. The first is the initial location of the target as it enters the region being covered. The second is following its track once it has been discovered. In this work, we outline an approach to target tracking. We present an energy-aware tracking algorithm that predicts the target track and activates nodes based on that prediction. We then discuss different energy management schemes that resolve tradeoffs between energy savings and track quality for a specified mission lifetime. Our energy management schemes perform better in terms of track quality and have an energy consumption similar to other schemes. We also consider energy harvesting in this energy management. We present a multitarget tracking algorithm; in connection with that, we present a filtering algorithm that improves the quality of tracking. We also study adaptive approaches to manage the tracking process to the observed mobility characteristics of the target. Such adaptive approaches are shown to have noticeable performance advantages.
  • Publication
    Synthesis and Study of Hybrid Organic – Inorganic Polyhedral Oligomeric Silsesquioxanes (poss) Based Polymers
    (2009-09-01) Gadodia, Gunjan A,
    Hybrid organic-inorganic materials represent a new class of materials having scientific and technological potential. In this thesis, Polyhedral Oligomeric Silsesquioxanes (POSS) are used as an inorganic building block which has been tethered to an organic polymer. POSS are silica precusors, having a well defined silsesquioxane cental core surrounded by an organic periphery which makes them compatible with monomers and possibly polymers. The objectives of this study are to (1) study the basic structures of POSS homopolymers, (2) to incorporate POSS building blocks by a bottomup approach into polymer chains and study the resulting morphologies, and (3) to study the thin film behavior of POSS block copolymers. PMA and styryl POSS homopolymers of different peripheries were synthesized by ATRP and mass spectrometry studies were carried out by MALDI-TOF and ESI. PMA POSS chains undergo a number of fragmentations while styrly POSS chains have a relatively robust backbone. Poly(ethylene-butylene-b-MAPOSS), AB type copolymers and poly(MAPOSS-b-styrene-b-MAPOSS), ABA type copolymers were synthesized by a combination of anionic and ATRP polymerization. Spheres, inverse cylinders, lamellar and crystalline lamellar morphologies were observed for the poly(ethylene-butylene-b- MAPOSS) copolymers. In the poly(MAPOSS-b-styrene-b-MAPOSS) copolymers, cylindrical, lamellar and perforated lamellar morphologies were obtained. Beyond the interaction parameter (χ), total degree of polymerization (N) and volume fraction (f), the conformational asymmetry (ε) also plays an important role in determining the morphology of these block copolymer. Crystallization of the POSS phase and better thermal properties were observed in the both block copolymers. Thin film studies of poly(MAPOSS-b-styrene-b-MAPOSS) copolymers showed that the microdomains can be oriented either parallel or perpendicular to the substrate depending upon the film thickness, morphology and relative volume fractions of the connecting blocks. By removal of the organic phase, ordered mesoporous low dielectric constant silica films were obtained. These hybrid block copolymers are a potential candidate for nanopatterning applications.