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The symptoms of malaria arise from cycles of red blood cell (RBC) invasion by Plasmodium spp. merozoites. This process has been studied by video microscopy for 50 years and the ordered stages of invasion have been well established for much longer. Merozoite entry is rapid and actively powered by a parasite acto-myosin motor. The canonical model for force production depends on arrays of a myosin motor (MyoA) working against short actin filaments connected to the external substrate. However, the molecular processes that underlie these well-described events, and the energetic barriers that the merozoite must overcome, remain unclear. Though MyoA has been shown to be critical for invasion of other parasite stages and species, the importance of MyoA has not been shown for Plasmodium falciparum merozoites. Work on other parasites has uncovered retrograde flow of plasma membrane and host cell activity as other sources of force production, casting doubt on the mechanical role of MyoA. Answering these questions has been hampered by limited structural understanding of the acto-myosin system in merozoites. In this study, conditional genetic modification of P. falciparum MyoA (PfMyoA) showed it is critical for invasion. The transgenic platform was then adapted for other motor proteins, showing that PfMyoA light chain PfELC is also critical but auxiliary motor PfMyoB is not. The range of defects in these mutants uncovered three distinct energetic barriers during merozoite invasion. Finally, probing the arrangement of the motor by electron microscopy revealed a multi-member complex of PfMyoA. Together, this study re-affirms the importance of PfMyoA for merozoite invasion and illuminates the energetic barriers that the motor is required to overcome.

The LHCb experiment is one of four experiments at the Large Hadron Collider. It is the next generation of heavy flavour experiment, designed to study CP violating processes and rare decays in the B system and will benefit from the large b-quark production cross-section in ''S =14 T.eV protonproton collisions. This will enable LHCb to record large numbers of events even for rare decay modes such as Bd-K*IJ+IJ', with a branching fraction of 1.22+0 . 38 ,0.32 x 10-6, that is discussed in this thesis. This thesis is divided into two parts. The first part focuses on the photon detectors of LHCb's Ring Imaging Cherenkov (RICH) detectors and their associated front-end electronics, discussing measurements made on these photon detectors during laboratory testing and culminating in a series of beam tests. The beam tests measured the performance of a 1/10th scale prototype RICH detector, providing an estimate for the combined efficiency of the HPD's binary readout and charge collection of Ecollection X Ereadout = 82�±3%. The second part of this thesis reports on LHCb's sensitivity to the decay as Bd-K*IJ+ IJ' in a Monte Carlo study with one nominal year (2 fb�·1) of data. With this data set (of 7000 events) LHCb should be able to make, for the first time, a precision measurement of the kinematic distribution of the particles in the decay that in many new physics models can have large departures from the Standard Model (SM) prediction. Particular attention is paid to the forward-backward asymmetry of the muons which changes with the invariant mass of the muon pair and crosses zero at a well defined value with small theoretical error in the SM. LHCb's precision on this zero crossing point is estimated at �±0.43 GeV2.

This dissertation explores the maternal role in subject formation and surveys varying depictions of this role in twentieth-century drama. While sifting through the genealogy of psychoanalytic theory, this project investigates how the dutiful mother, spawned by phallocentric notions of subjectivity and emerging in works like Lorca’s The House of Bernarda Alba and Norman’s’night, Mother, passively yields to prevailing ideology and integrates her children into oppressive Symbolic structures. By examining the “correctives” to the Freudian-Lacanian paradigms proffered by Kristeva and Irigaray, this dissertation identifies how, when challenging patriarchal conceptions of the maternal function, these feminist philosophers each rely heavily on both Heidegger’s fundamental ontology and Arendtian political action. Kristeva and Irigaray provide the theoretical framework from which conceptual space for the revolutionary mother can be carved. This mother, in contradistinction to the Freudian-Lacanian mother, sanctions existing cultural practices only when she deems them ethically sound. Emerging in works like Hansberry’s A Raisin in the Sun and Kushner’s Homebody/Kabul, the potentials for revolt churning in the maternal function clearly surface. The revolutionary mother urges her children to reject injustice, to respect difference, and to pursue, in Heideggerian terms, the authentic mode of Being. This work concludes by arguing that drama presents the ideal mode of literary representation for expressing the revolutionary power of the maternal function. As Heidegger, Arendt, Kristeva, and Irigaray each depart from a tradition of detached, universal objectivity by re-inserting the physical body into philosophical discourse, theatrical performance, via performance, depicts literature embodied. By presenting convergent data from the emerging field of cognitive science, this work identifies intersections between corporeal philosophy and dramatic performance and how these intersections can help us, when necessary, to restructure our culture, our ethics, and our interactions with other human beings.

Using archaeological, ethnohistoric, and ethnographic sources, I examine how the specific processes of (1) inter-regional exchange, (2) warfare, (3) elite colonization, and (4) colonization by whole communities, influence the development of a Postclassic Maya state. The study deals with the following two questions: (1) can these specific processes of inter-polity relations be identified in the archaeological record and , (2) by examining changes in their relative importance through time can we better underst and the evolution of a particular secondary state? In order to answer these questions, I demonstrate that, as each process shifts to prominence, it will have its own distinguishable impact on the social, political, and economic relations among social units within a community. I also argue that, because those relations are expressed and maintained by way of material culture, each specific process has its own discernible affects on the changes in archaeologically observable artifacts and features. A sample of elite and non-elite houses at the Postclassic Maya site of Canajaste, in Chiapas, Mexico were excavated in order to test these ideas. The houses were excavated so that the trajectories of changes in house features, styles, burials, artifacts, and subsistence remains could be monitored for each house group. By comparing the changes that the elite houses underwent with the changes that the non-elite underwent, it was possible to observe the changing relations between the two social classes, and thus, infer changes in the underlying specific processes. Canajaste began as a complete colony towards the end of the Early Postclassic period (ca. A.D. 1200). During that period the elite progressively distanced themselves from the non-elite by controlling a brisk interregional trade. Near the end of that period there was an increase in the scale and frequency of warfare as trade declined. As warfare increased, the community continued to grow, but the material differences between the two social classes diminished. By the end of the Late Postclassic period, trade began to increase once more, but as it did, warfare remained an important aspect of inter-polity relations. The main conclusion is that, in order to underst and the evolution of complex society, we must be able to trace the timing and relative importance of a range of specific processes that lead to socio-political change. Ultimately, it will be necessary to accumulate a series of case studies such as this in order to explain variation in the processes of state development.

Selection for high levels of freeze resistance in winter barley (Hordeum vulgare L.) has resulted in development of cultivars which: 1) contain low RNase I activity in young shoot tissue and 2) a single RNase activity band in expanding leaf tissue at Rf 0.08. By contrast, seedlings of less-hardy cultivars typically have; 1) two RNase polymorphs (Rf=0.54 and 0.58) in young shoot tissue and 2) fours polymorphs (Rf-054, 0.58, 0.64 and 0.81) in expanding leaf samples. All enzymes migrate toward the anode (ph 7.9) and only the fastest moving band is common to expanded leaves in both groups of plants. Enzyme activity comparisons were made in the presence of EDTA. A technique is described which requires minimal preparation of tissue extracts for electrophoresis on 3 mm diameter x55 mm length acrylamide gels. RNase assays on leaf samples as small as 30 mg fresh weight can be made. The technique is capable of rapidly determining the number of RNase polymorphs within a population and also detects variation in levels of activity of component enzymes. It appears to be an adequate procedure of studying inheritance of RNase in barley leaf tissue.