Some investigations into the structure of local gauge-invariant field theories

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Calibration of a shock wave position sensor using artificial neural networks

This report discusses the calibration of a shock wave position sensor. The position sensor works by using artificial neural networks to map cropped CCD frames of the shadows of the shock wave into the value of the shock wave position. This project was done as a tutorial demonstration of method and feasibility. It used a laboratory shadowgraph, nozzle, and commercial neural network package. The results were quite good, indicating that artificial neural networks can be used efficiently to automate the semi-quantitative applications of flow visualization

A study of the mineral composition of pottery sherds from, Malyan, Iran

From 1971 through 1978 William M. Sumner, of the Ohio State University Department of Anthropology, conducted a five season preliminary excavation at Tal-e-Malyan, Iran. A result of his work was the discovery of a new phase of occupation, which is now known as the Banesh Phase (c. 3400-2600 B.C.). Two broad catagories of Banesh ware have been identified; one is a coarse, low fired straw tempered ware and the second is a hard grit tempered ware which occurs in several varieties, (Sumner 1980). Younger, Islamic wares (c. 800-1900 A.D.) are very similar in appearance to the older Banesh wares. Consequently the two different pottery wares can be confused. By conducting a mineral analysis on the two different wares it can now be shown that some distinguishing characteristics do exist. Twenty five Malyan sherds, ranging in size from one inch to two inches were donated for this study. In order to eliminate bias all information regarding the archaeological context of the sherds was withheld until the mineral analysis and catagorization of each sherd was completed. Only Mr. Sumner, knew that the sherds represented Banesh and Islamic pottery types. The purpose of this study was to see if textural mineral analysis of the sherds would permit catagorization. After the catagorizations were completed they were matched to Mr. Sumner's archaeological catagorizations. The results showed that the Islamic sherds characteristically contained micrite, carbonate grains, quartz, feldspar, and a low large percentage of iron oxides. The Banesh sherds contained, either large percentages of iron oxides, or else differed in composition from the characteristic Islamic sherd constituents. The polarizing microscope, Vreland Spectroscope, and x-ray analyzer were utilized in the analysis.No embarg

Complementary transcriptomic, lipidomic, and targeted functional genetic analyses in cultured Drosophila cells highlight the role of glycerophospholipid metabolism in Flock House virus RNA replication

Abstract Background Cellular membranes are crucial host components utilized by positive-strand RNA viruses for replication of their genomes. Published studies have suggested that the synthesis and distribution of membrane lipids are particularly important for the assembly and function of positive-strand RNA virus replication complexes. However, the impact of specific lipid metabolism pathways in this process have not been well defined, nor have potential changes in lipid expression associated with positive-strand RNA virus replication been examined in detail. Results In this study we used parallel and complementary global and targeted approaches to examine the impact of lipid metabolism on the replication of the well-studied model alphanodavirus Flock House virus (FHV). We found that FHV RNA replication in cultured Drosophila S2 cells stimulated the transcriptional upregulation of several lipid metabolism genes, and was also associated with increased phosphatidylcholine accumulation with preferential increases in lipid molecules with longer and unsaturated acyl chains. Furthermore, targeted RNA interference-mediated downregulation of candidate glycerophospholipid metabolism genes revealed a functional role of several genes in virus replication. In particular, we found that downregulation of Cct1 or Cct2, which encode essential enzymes for phosphatidylcholine biosynthesis, suppressed FHV RNA replication. Conclusion These results indicate that glycerophospholipid metabolism, and in particular phosphatidylcholine biosynthesis, plays an important role in FHV RNA replication. Furthermore, they provide a framework in which to further explore the impact of specific steps in lipid metabolism on FHV replication, and potentially identify novel cellular targets for the development of drugs to inhibit positive-strand RNA viruses.http://deepblue.lib.umich.edu/bitstream/2027.42/78268/1/1471-2164-11-183.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78268/2/1471-2164-11-183-S3.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78268/3/1471-2164-11-183-S2.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78268/4/1471-2164-11-183.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/78268/5/1471-2164-11-183-S4.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78268/6/1471-2164-11-183-S1.XLSPeer Reviewe

Domain growth in alloys

This thesis describes Monte-Carlo computer simulations of binary alloys, with comparisons between small angle neutron scattering (SANS) data, and numerically integrated solutions to the Cahn-Hilliard-Cook (CHC) equation. Elementary theories for droplet growth are also compared with computer simulated data. Monte-Carlo dynamical algorithms are investigated in detail, with special regard for universal dynamical times. The computer simulated systems are Fourier transformed to yield partial structure functions which are compared with SANS data for the binary Iron-Chromium system. A relation between real time and simulation time is found. Cluster statistics are measured in the simulated systems, and compared to droplet formation in the Copper-Cobalt system. Some scattering data for the complex steel PE16 is also discussed. The characterisation of domain size and its growth with time are investigated, and scaling laws fitted to real and simulated data. The simple scaling law of Lifshitz and Slyozov is found to be inadequate, and corrections such as those suggested by Huse, are necessary. Scaling behaviour is studied for the low-concentration nucleation regime and the high-concentration spinodal-decomposition regime. The need for multi-scaling is also considered. The effect of noise and fluctuations in the simulations is considered in the MonteCarlo model, a cellular-automaton (CA) model and in the Cahn-Billiard-Cook equation. The Cook noise term in the CHC equation is found to be important for correct growth scaling properties

Graduates of Character - Values and Character: Higher Education and Graduate Employment

Graduates of Character is the product of an empirical enquiry into the values, virtues, dispositions and attitudes of a sample of students and employees who volunteered to be involved. The research team sought host sites which would offer a diverse set of interviewees in gender, ethnicity, religion and aspiration. In this study we discuss what character is taken to mean by students and employees in their years of higher education and employment. We examine what their values are, what they gain from the university, what they believe employers look for when recruiting, what they hope to give to an employer, and what they expect from their employer. We then explore who or what influenced their values and moral development. We also examined the role of the personal tutor or mentor, and the persons or services to which they might go for personal and/or professional support

An Alternative Statistical Measure for Racially Polarized Voting

Measurements of the existence and extent of racially polarized voting are often at the forefront of the evidence presented in vote dilution litigation. Previous models used in the measurement of racially polarized voting have been inadequate for a broad range of cases. The source of this inadequacy is that these models were not based upon assumptions about individual behavior. A new model, which is based on reasonable assumptions about individual behavior and can be approximated by a varying parameters model, is derived. By contrasting the new model with the other models, it is shown that both the correlation coefficient and linear regression can lead to inaccurate, misleading or incorrect conclusions about the state of racial polarization in the electorate. After providing a straightforward statistical test for identifying misspecification and showing how to obtain estimates for this model by the method of maximum likelihood, the model is compared with an individual level data set of an election where racially polarized voting occurred (1988 California presidential primacy). A new measure for the estimation of racially polarized voting is then proposed

Creation of a Creation Myth: Steps Towards a Promethean Age

The role of myth in the context of religion has had considerable theoretical attention. Both psychological and anthropological interpretations of myth have tended to view religion as a modus operandi of cultural behaviours. While such interpretations may be insightful it begs the question as to the role of myth for guiding future societies. This paper will pose the idea that a new myth is needed in order to tackle the major global challenges which humanity is facing. This promethean myth will use ideas from traditionally based religions but will not be dependent on them

Dragons: Myth and the Cosmic Powers

This essay investigates the significance of dragon mythology in early civilizations. Three mythical dragons are be considered, Zhulong, Apep and Makara. These examples show that the symbol of the dragon represents a triune principle of generativity, vitality and knowledge