Now showing items 10203-10222 of 19809


      Balch, Dennis Robert, 1949- (The University of Arizona., 1977)
    • Isolation and molecular characterization of a gene from Drosophila melanogaster encoding a predicted Rho guanine nucleotide exchange factor

      Manseau, Lynn J.; Werner, Lisa Anne, 1958- (The University of Arizona., 1997)
      I conducted a chromosomal walk in the 38C region on the second chromosome to execute the molecular analysis of spire, (spir), a Drosophila maternal effect locus required for establishment of both the dorsal-ventral and anterior-posterior axes during embryonic development. This analysis resulted in the isolation and mapping of approximately 300 kb of DNA from 38D1 to 38C2. I identified a gene in this region, which I named Drosophila Rho-type Guanine Nucleotide Exchange Factor (DrtGEF) that has substantial sequence homology to a distinct class of proto-oncogenes that includes DBL, VAV, Tiam-1, ost and ect-2. It has predicted Rho or Rac guanine exchange factor (Rho/RacGEF) and pleckstrin homology (PH) domains with the PH domain being immediately downstream of the Rho/RacGEF domain (Cerione and Zheng 1996). Rho/RacGEFs catalyze the dissociation of GDP from the Rho/Rac subfamily of ras-like GTPases, thus activating the target Rho/Rac. Members of the Rho/Rac subfamily regulate organization of the actin cytoskeleton, which controls the morphology, adhesion and motility of cells. DrtGEF mRNA is present throughout oogenesis and embryogenesis. Of particular interest, DrtGEF mRNA is most abundant in furrows and folds of the embryo where cell shapes are changing and the cytoskeleton is likely to be undergoing a reorganization.
    • Isolation of a set of mutations linked to the TAG-1 locus of Bacillus subtilis, which perturb cell surface properties.

      Mendelson, Neil; Briehl, Margaret Marie. (The University of Arizona., 1988)
      The physiological role of the teichoic acid polymers found in Gram-positive bacterial cell walls is not known. Studies of Bacillus subtilis hybrid strains implicate a defined chromosomal region, which includes the tag-1 locus, as necessary for teichoic acid biosynthesis. A set of ten mutants carrying lesions in this region was identified from among forty-four temperature-sensitive (ts) mutants generated by nitrosoguanidine mutagenesis and bacteriophage 029 selection. This protocol gave a population enriched for ts, versus auxotrophic, mutants. For each of the ten mutants, the frequency of genetic reconstruction, or correction, of the ts phenotype indicated that it was due to change(s) in a single gene. Results of two-factor transformation crosses sorted the mutants into three complementation groups; all ten could complement tag-1. Mutants in two complementation groups were transformed to ts⁺ with cloned rodC DNA. The map order of the newly isolated ts markers was determined from the results of two factor crosses. Orientation with respect to the hisA marker was inferred from transduction experiments. The newly isolated strains were shown to be conditional rod⁻ mutants. Growth at 48°C resulted in reduced growth rates and spherically shaped cells. Additional phenotypes seen for some mutants, namely 029 phage resistance and ts spore outgrowth, appeared closely associated with the ts rod⁻ mutation. Wall phosphate content for two of the mutants, following growth at 48°C, was found to be reduced in comparison to the wild-type control. Taken together these results lend support to the argument that the tag-1 region of the chromosome, which most likely directs teichoic acid biosynthesis, is important for establishment and maintenance of the normal bacillary morphology seen for B. subtilis. The importance of other gene products to the organization of newly synthesized wall was examined using B. subtilis macrofibers. Left- and right-handed macrofibers were converted to spheroplasts and the multi-celled structures regenerated under the two sets of conditions conducive for production of the original, and inverse hand. The helix hands observed for the regenerated structures always corresponded to those expected on the basis of the parental genotype.
    • Isolation of reactive intermediates in the cycloaddition reactions of alkynes promoted by tantalum phenoxide complexes.

      Wigley, David E.; Strickler, Jamie Ray.; Enemark, John H.; Lichtenberger, Dennis L.; Mash, Eugene A.; Smith, Mark A. (The University of Arizona., 1990)
      Intermediates in the cyclotrimerization of alkynes have been isolated using the tantalum phenoxide reagents, Ta(DIPP)₂Cl₃(OEt₂) and Ta(DIPP)₃Cl₂(OEt₂) (DIPP = 2,6-diisopropylphenoxide). The degree of cyclization has been controlled by effecting either the sterics of the metal center or the alkyne itself. Reduction of the less congested bis-phenoxide complex, Ta(DIPP)₂Cl₃(OEt₂), by two electrons in the presence of progressively smaller alkynes allowed the selective synthesis of successively higher coordinated cyclooligomers (alkyne adducts, metalacyclopentadienes, and 7-metalanorbornadienes, respectively). This complex also catalytically cyclotrimerizes phenylacetylene upon reduction. Besides resembling proposed intermediates in the catalytic cyclotrimerization of alkynes by transition metals, the direct conversion of each of these cyclooligomers to the next higher or lower step in the proposed mechanism was demonstrated. The alkyne adduct reacted with additional alkyne to provide metallacyclopentadienes in a very regioselective fashion (i.e. (DIPP)₃Ta(PhC=CPh) reacted with Me₃CC=CH to provide (DIPP)₃Ta(CPh=CPhCH=CCME₃)). The metallacyclic complex, (DIPP)₂ClTa(CCMe₃=CHCH=CCMe₃) was shown to undergo an unprecendented dissociation into a bis-alkyne complex upon thermolysis before rearranging to the less-congested metallacycle, (DIPP)₂ClTa(CCMe₃=CHCCMe₃=CH). This complex then reacted with an additional equivalent of t-butylacetylene to provide the arene complex, (η⁶- C₆H₃ᵗBu₃)Ta(DIPP)₂Cl, or with Me₃CC=N to yield η²-(N,C)-NC₅H₂ᵗBu₃Ta(DIPP)₂Cl. The alkyne adduct, (DIPP)₃Ta(PhC=CPh), also undergoes regioselective cross-coupling reactions with benzaldehyde to provide (DIPP)₃Ta(CPh=CPhCH(Ph)O). This metallacyclic alkoxide reacted with an additional equivalent of benzaldehyde and then undergoes a hydride transfer to provide the Meerwein-Ponndorf-Verley/Oppenauer type redox intermediate, (DIPP)₃(PhCH₂O)Ta(η²-CPh=CPhCPh=O). Nitriles coordinate to (DIPP)₃Ta(PhC=CPh) to provide the complexes, (DIPP)₃Ta(PhC=CPh) (RC=N). Nitriles which contain α-hydrogen react further to provide the metallacycloenamine complexes (DIPP)₃Ta(CPh=CPhC(=CHR)NH).$ These complexes have been shown to arise through a metallacycloimine followed by an unusual intermolecular tautomerization, as inferred from deuterium labeling and crossover experiments.
    • Isolation, characterization, cDNA cloning and deduced amino acid sequence of transferrin from the tobacco hornworm, Manduca sexta.

      Law, John; Bartfeld, Neil Stuart.; Dieckmann, Carol; Vierling, Elizabeth; Tollin, Gordon (The University of Arizona., 1990)
      An iron-binding 77 kilodalton glycoprotein was isolated from hemolymph of the adult sphinx moth, Manduca sexta. This protein bound a single ferric ion both in vivo and in vitro and had a secondary structure similar to that of human serum transferrin and human lactoferrin, as judged by CD spectra. Antiserum generated against this protein was used to screen a fifth instar, day four, larval fat body cDNA library. A 2.0 kilobase clone was isolated and used to probe a northern blot of both total and poly(A)⁺ RNA from fat body, revealing a message of 2.3 kilobases. The message is expressed throughout the fourth instar, fifth instar, wandering, pupal and adult stages. The 2.0 kilobase clone selected an mRNA which, when translated in vitro, produced an immunoprecipitable 77 kDa protein. The 2.0 kb clone was used as a probe to further screen the cDNA library, resulting in the isolation of three full-length clones. The complete nucleotide sequence of one 2183 base pair cDNA insert was determined. The deduced amino acid sequence contained an 18 amino acid signal sequence which, when cleaved, resulted in a mature protein sequence of 663 amino acids with a calculated molecular weight of 73,436. The first 34 residues of the mature protein were identical to those determined by Edman degradation of the intact protein. The sequence contained four consensus N-linked glycosylation sites (Asn-X-Thr/Ser). The sequence was used to search the National Biomedical Research Foundation protein database. The proteins exhibiting the greatest similarity were human serum transferrin, chicken ovotransferrin, human lactoferrin and human melanotransferrin. When the five sequences were aligned using a multiple alignment program, the insect protein contained approximately 27% identical residues when compared to each of the other transferrins. The greatest areas of similarity were around the iron binding sites. Moreover, 23 of the 24 cysteine residues in the insect protein occupied identical positions as compared to the other transferrins, indicating a similar overall tertiary structure. The insect protein also exhibited some internal homology between the N-terminal and C-terminal halves of the molecule. Ligands capable of binding an iron atom were present in the N-terminal half, but most were lacking in the C-terminal half. Based upon sequence comparisons and other structural and functional data, we believe that we have isolated and sequenced an invertebrate transferrin, the first such molecule to have its entire sequence determined.
    • Isolation, characterization, functional properties and biological evaluation of tepary bean (Phaseolus acutifolius) proteins.

      Idouraine, Ahmed.; Weber, Charles W.; Reid, Bob L.; Sheehan, Edward T.; Tinsley, Ann M.; Price, Ralph L. (The University of Arizona., 1993)
      Tepary bean (Phaseolus acutifolius) proteins were fractionated sequentially according to solubility in sodium phosphate buffer (SPB), sodium chloride (salt), ethanol, 2-mercaptoethanol (2-ME), and sodium dodecyl sulfate (SDS) solutions. Isolated protein fractions were analyzed for protein, amino acids (AA), trypsin inhibitor (TIA) and hemagglutinating activities (HA), phytic acid (PA), and characterized by SDS-PAGE. Tepary flour (TF) and SPB and salt protein fractions were tested for protein solubility, apparent viscosity, heat coagulability, emulsion capacity, foaming and foam capacity, and water and oil absorption capacity in comparison to soy protein isolate (SPI). Raw, cooked, and autoclaved TF or SPB protein fraction were evaluated for their nutritive value using mice. SPB and salt soluble protein fractions represented 83.2 and 13.7% of extractable protein, respectively. AA of SPB, salt, and 2-ME protein fractions were not significantly different (P < 0.05). Cysteine was concentrated in ethanol protein fraction. SDS-PAGE patterns of SPB and salt protein fractions contained 37 and 27 polypeptides, respectively. Major bands were at 29, 45, and 45 KDa. TIA was extremely high in ethanol protein fraction (161 TIU/mg sample). HA and PA were high in SPB protein fraction and TF (29,000 and 20,000 HU/g sample; 4.61 and 6.83 mg/g sample, respectively). Solubilities of SPB and salt protein fractions compared to SPI were higher at pH 1-4 but similar at pH 8-12. Although SPI had significantly higher viscosity than tepary proteins, TF and SPB protein fraction exhibited significantly higher heat coagulability and foaming properties. Salt protein fraction did not coagulate upon heating to 100°C. It also formed a weaker and less stable foam and had significantly lower emulsion capacity than TF, TA, and SPI. Tepary proteins absorbed significantly higher amounts of oil than SPI. Both raw and 20-min-autoclaved TF or SPB protein fraction, when included in the diets were deadly to mice while soaked then 20-min-cooked tepary beans or 40-min-autoclaved SPB protein fraction eliminated toxicity and led to a perceptible weight gain (0.30 and 0.23 g/day), PER (0.97 and 0.82), and digestibility (83.54 and 54.37%), respectively. Autoclaving TF or PE for 60 min had a significant depressing effect on feed intake, weight gain, and PER. Processing eliminated HA and reduced TIA by 91 to 99%.
    • Isomorphism of automorphism groups of mixed modules over a complete discrete valuation ring.

      May, Warren; Adongo, Harun Paulo Kasera.; Toubassi, E.; Grove, L. (The University of Arizona., 1991)
      Isomorphisms of automorphism groups of reduced torsion abelian p-groups have recently been classified by W. Liebert [L1] and [L2] for p ≠ 2. The primary objective of this study is to investigate the isomorphisms of automorphism groups of reduced mixed modules M and N of torsion-free ranks < ∞ over a complete discrete valuation ring with totally projective torsion submodules t(M) and t(N) respectively. For modules over ℤ(p), p ≠ 2, we show that if AutM and AutN are isomorphic and the quotient modules M/t(M) and N /t(N) are divisible, then M ≃ N.

      May, Warren; ULLERY, WILLIAM DAVIS. (The University of Arizona., 1983)
      Let R be a commutative ring with identity and let G and H be abelian groups with the group algebras RG and RH isomorphic as R-algebras. In this dissertation we investigate the relationships between G and H. Let inv(R) denote the set of rational prime numbers that are units in R and let G(R) (respectively, H(R)) be the direct sum of the p-components of G (respectively, H) with p ∈ inv(R). It is known that if G(R) or H(R) is nontrivial then it is not necessarily true that G and H are isomorphic. However, if R is an integral domain of characteristic 0 or a finitely generated indecomposable ring of characteristic 0 then G/G(R) ≅ H/H(R). This leads us to make the following definition: We say that R satisfies the Isomorphism Theorem if whenever RG ≅ RH as R-algebras for abelian groups G and H then G/G(R) ≅ H/H(R). Thus integral domains of characteristic 0 and finitely generated indecomposable rings of characteristic 0 satisfy the Isomorphism Theorem. Our first major result shows that indecomposable rings of characteristic 0 (no restrictions on generation) satisfy the Isomorphism theorem. It has been conjectured that all rings R satisfy the Isomorphism Theorem. However, we show that the conjecture may fail if nontrivial idempotents are present in R. This leads us to consider necessary and sufficient conditions for rings to satisfy the Isomorphism Theorem. We say that R is an ND-ring if whenever R is written as a finite product of rings then one of the factors, say Rᵢ, satisfies inv(Rᵢ) = inv(R). We show that every ring satisfying the Isomorphism Theorem is an ND-ring. Moreover, if R is an ND-ring and if inv(R) is not the complement of a single prime we show that R must satisfy the Isomorphism Theorem. This result together with some other fragmentary evidence leads us to conjecture that R satisfies the Isomorphism Theorem if and only if R is an ND-ring. Finally we obtain several equivalent formulations of our conjecture. Among them is the result that every ND-ring satisfies the Isomorphism Theorem if and only if every field of prime characteristic satisfies the Isomorphism Theorem.
    • Isopoda Cymothoidae (Crustacea) of the Gulf of California

      Brusca, Richard C. (The University of Arizona., 1975)

      Schrage, Dale Leonard, 1944- (The University of Arizona., 1970)
    • Isotopic and chemical considerations in radiocarbon dating of groundwater within the arid Tucson Basin, Arizona.

      Wallick, Ed.; Long, Austin; Simpson, Eugene S.; Damon, Paul; Dutt, Gordon R. (The University of Arizona., 1973)
      A chemical-isotopic equilibrium model was developed for adjustment of radiocarbon ages of groundwater from the arid Tucson basin for dilution of the initial groundwater C-14 activity by the solution of soil calcite having a C-14 of 25 ± 19% modern. Input to the model consisted of the laboratory chemical analyses for Ca⁺⁺, Mg⁺⁺, Na⁺, H₄SiO₄, SO₄⁼, HCO₃⁻, CO₃⁼, NO₃⁻, and pH, and δ C-13 for the total dissolved carbon in the groundwater. Output consisted of the equilibrium chemical composition of the groundwater, the ratio of soil CO₂ derived to total dissolved carbon, Q, and δ C-13 of total dissolved carbon, H₂CO₃, HCO₃⁻, and CO₃⁼, and δ C-13 for the soil CO₂ and calcite that initially dissolved in the surface water as it equilibrated with soil minerals. Radiocarbon age of the groundwater is computed from the equation T = 8270 ln [(Q + (1-Q) A(CaCO₃)/Am] where T is the age in years before A.D. 1950, A(CaCO₃) is the soil calcite activity and Am is the measured activity for the dissolved carbonate in the groundwater, both with respect to modern wood. The validity of the model was tested by comparing the predicted values for δ C-13 (CO₂), δ C-13 (CaCO₃) with measured values for samples from the Tucson basin. δ C-13 (CO 2) calculated = (-12.9 ± 1.9) per mil PDB. δ C-13 (CO2) measured = (-15.1 ± 2.8) per mil PDB. δ C-13 (CaCO3) calculated = (-3.9 ± 1.7) per nil PDB. δ C-13 (CaCO3) measured = (-3.6 ± 1.7) per mil PDB. On the basis of these results, the model adequately describes the natural system and may prove useful in future radiocarbon dating work in desert regions.
    • Isotopic and geochemical characteristics of Laramide igneous rocks in Arizona.

      Titley, Spencer R.; Lang, James Robert.; Barton, Mark D.; Snow, Eleanour A. (The University of Arizona., 1991)
      Isotopic and trace element data on igneous rocks in nine multiphase magmatic complexes of Laramide age in Arizona place constraints on their petrogenesis and on the factors leading to the formation of porphyry copper deposits. The igneous rocks form a data array from ∊Nd(T) and Srₒ values of 0 and 0.704, to -14 and >0.710, respectively. Isotopic compositions indicate that early, intermediate volcanic rocks retained a mantle component whereas later intrusions were derived predominantly from Precambrian lower crust. The REE display temporally systematic behavior. Progressively younger igneous rocks in a district show a decreasing concentration of REE which is more pronounced for the HREE than for the LREE; they acquire greater upward concavity in their HREE profiles; and the Eu anomaly steadily becomes less negative. An increasing role for hornblende is indicated, either in the residuum of melting or as a fractionating phase. The evolving REE and isotopic behavior parallels the progression from barren, to subproductive, to productive intrusions. The geochemical behavior can be understood in the broader context of magmagenesis at the Laramide convergent margin. Early in the Laramide, the crust was cool and brittle, thereby allowing magmas formed in the mantle wedge as a consequence of volatile loss from the descending slab to ascend to high crustal levels. As the crust warmed the ascent of mantle-derived magmas was arrested in the lower crust where they induced anatexis in Precambrian crust. Three related models can account for the systematic REE behavior, crustal anatexis, and the timing of Laramide metallogenesis: (1) metasomatism of the lower crust, (2) progressively greater assimilation of hydrous crust by mantle-derived melts, and (3) migration of the anatectic zone into more hydrous rocks at higher crustal levels. Each process would allow melting to continue in confined columns of crust as well as provide increasingly volatile-rich magmas that were necessary for melts to evolve fluids capable of forming large porphyry copper deposits. The ultimate ability of a melt to form a porphyry copper deposit may, therefore, depend on characteristics obtained either in its crustal source region or during its passage through the crust.
    • Isotopic Evidence for the Provenance of Turquoise, Mineral Paints, and Metals in the Southwestern United States

      Ruiz, Joaquin; Thibodeau, Alyson Marie; Killick, David J.; Chesley, John T.; Quade, Jay; Reiners, Peter; Ruiz, Joaquin (The University of Arizona., 2012)
      Lead and strontium isotopes are two powerful tracers that can be used to identify or constrain the provenance of a wide range of archaeological materials, but these two isotopic tracers have been rarely employed to infer the sources of artifacts in the southwestern USA. This dissertation contains four studies that demonstrate how these isotopic systems can address questions about the sources of three types of archaeological materials found in this region: turquoise, lead-based glaze-paints, and metals. The analysis of 116 samples of turquoise from 17 deposits in the southwestern USA reveals that lead and strontium isotopes are robust and sensitive tracers of turquoise at multiple scales. Isotopic variation among turquoise deposits correlates with broad regional differences in the geologic and tectonic setting of the rocks and mineral deposits which host turquoise mineralization. Many turquoise deposits also have unique isotopic signatures that will enable insights into ancient patterns of turquoise acquisition at regional and local levels. To show the utility of these tracers when applied to archaeological turquoise, I use lead and strontium isotopic measurements to establish that the Silver Bell Mountains are the likely source turquoise found at the Redtail site in the Tucson Basin, Arizona, USA. This dissertation also contains new, high-precision isotopic ratios of lead ores (galena and cerrusite) from four mining districts in New Mexico, including the Cerrillos Hills. All districts studied are possible sources of lead used by Pueblo IV communities to produce glaze paints. These new measurements, made by multiple-collector ICP-MS, define the isotopic composition of the ore deposits with greater precision and accuracy than achieved in previous studies, indicating an opportunity to improve interpretations about the provenance of lead in glaze paints. Lead isotopes are also found to be useful tools for identifying lead and copper metal associated with the 1540-1542 Vázquez de Coronado expedition. Lead shot and copper crossbow boltheads from two sites with archaeological evidence for the expedition's presence were determined to share similar or identical lead isotopic ratios. I propose this specific isotopic "fingerprint" can be used to identify other artifacts belonging to the expedition in the Southwest.
    • Isotopic Logs of The Sea of Cortez: Oxygen and Carbon Stable Isotopes in Otoliths of Marine Fish Record the Impact of Diverting the Colorado River from the Sea

      Rowell, Kirsten; Flessa, Karl W.; Flessa, Karl W.; Dettman, David L.; Gerber, Leah; Glenn, Ed; Reinthal, Peter (The University of Arizona., 2006)
      I use microchemistry in fish otoliths to test the hypothesis that diverting Colorado River flow from reaching the Gulf of California has impacted two endemic fish: the threatened gulf Corvina, (Cynoscion othonopterus) and the endangered totoaba (Totoaba macdonaldi). The oxygen and carbon stable isotope ratios in otoliths help to reconstruct conditions of the environment during key life history stages before and after the damming and diverting the Colorado River. The δ¹⁸O in otoliths illustrate that both C. othonopterus and T. macdonaldi seek out brackish habitat provided by the Colorado River during their early life history. The δ¹⁸O of C. othonopterus otolith have a strong negative correlation with Colorado River flow. I found that previously published relationships between otolith δ¹⁸O and ambient temperature along with δ¹⁸O of the water are sufficient to predict ranges of expected δ¹⁸O values for T. macdonaldi in the field. The δ¹⁸O in pre-dam T. macdonaldi otoliths show significant divergence from modern T. macdonaldi otoliths’ values, indicating that these fish used the brackish waters of the Colorado River estuary. The δ¹³C in T. macdonaldi otoliths has a significant proportion of its δ¹³C derived from diet. Pre-dam T. macdonaldi juveniles have a significantly different diet, which reflects that the Colorado River estuary had higher productivity before diversion of the river. Lastly, T. macdonaldi grew faster before the dams and in association with Colorado River flow measured by the δ¹⁸O.

      Mayland, H. F. (Henry F.) (The University of Arizona., 1965)
    • Issues in comparative Uto-Aztecan morphosyntax

      Harley, Heidi; Hill, Jane H.; Haugen, Jason D. (The University of Arizona., 2004)
      This dissertation seeks to test recent important theoretical ideas in the Principles and Parameters and Distributed Morphology frameworks against data from the relatively under-studied Uto-Aztecan languages. In this work I focus on the morphology of reduplication, noun incorporation and related derivational morphology, and the diachronic development of the polysynthetic morphological type in one sub-branch of the family (Corachol-Aztecan). With respect to prosodic morphology, I argue that the comparative Uto-Aztecan evidence suggests that reduplicants should be viewed as morphological pieces, and I analyze them as Vocabulary Items inserted into syntactic slots at Morphological Structure. I also argue that the evidence of cognate reduplication patterns across Uto-Aztecan supports a prosodic view of morphology, as well as the constraint-ranking approach to morphophonology. With respect to noun incorporation and derivational morphology, I argue that the comparative Uto-Aztecan evidence supports the view that denominal verbs are a sub-class of noun-incorporating verbs. I survey the noun incorporation types in Uto-Aztecan and classify NI in these languages into four types: N-V compounding, syntactic NI, classificatory NI, and "object polysynthesis". I offer a unified syntactic account of these types, maintaining that each is formed via head-movement in syntax. I provide a novel approach to hyponomous objects, suggesting that these are in argument positions, and that they are derived via the Late Insertion of material that is not cognate to the incorporated noun, but which is inserted into the lower copy of a movement chain. Non-theme "nominal" roots incorporated into verbs, such as instrumental prefixes, are analyzed as adverbial elements Merged directly into the verbal position. Finally, I argue that this theoretical analysis of NI leads naturally to a diachronic account of the development of polysynthesis in Nahuatl. I show that the crucial aspects of polysynthesis, subject and object pronominal marking on the verb as well as syntactic noun incorporation, have analogues elsewhere in Uto-Aztecan, and I offer a reconstruction of the likely stages of the development of polysynthesis in Nahuatl, each of which have attestation elsewhere in the family.
    • Issues in Control and Monitoring of Intelligent Vehicles

      Wang, Fei-Yue; LI, LI; Wang, Fei-Yue; Szidarovszky, Ferenc; Smith, J. Cole (The University of Arizona., 2005)
      Inspired by the recent developments, we studied some recent developments and research trends in intelligent vehicle sensing and control tasks. We emphasize on advanced vehicle motion control techniques and intelligent tires. The main research motivation is to improve drivers/passengers' comfort and safety as well as highway capacity and efficiency.

      Andrews, Gregory R.; Olsson, Ronald Arthur; Schlichting, Rick; Downey, Pete; Williams, Ted; Hill, Fred (The University of Arizona., 1986)
      This dissertation examines fundamental issues that face the designers of any distributed programming language. It considers how programs are structured, how processes communicate and synchronize, and how hardware failures are represented and handled. We discuss each of these issues and argue for a particular approach based on our application domain: distributed systems (such as distributed operating systems) and distributed user applications. We conclude that a language for such applications should include the following mechanisms: dynamic modules, shared variables (within a module), dynamic processes, synchronous and asynchronous forms of message passing, rendezvous, concurrent invocation, and early reply. We then describe the current SR language, which has evolved considerably based on our experience. SR provides the above mechanisms in a way that is expressive yet simple. SR resolves the tension between expressiveness and simplicity by providing a variety of mechanisms based on only a few underlying concepts. The main language constructs are still resources and operations. Resources encapsulate processes and the variables they share; operations provide the primary mechanism for process interaction. One way in which SR has changed is that both resources and processes are now created dynamically. Another change is that all the common mechanisms for process interaction--local and remote procedure call, rendezvous, dynamic process creation, asynchronous message passing, and semaphores--are now supported by a novel integration of the mechanisms for invoking and servicing operations. Many small and several larger examples illustrate SR's mechanisms and the interplay between them; these examples also demonstrate the language's expressiveness and flexibility. We then describe our implementation of SR. The compiler, linker, and run-time support are summarized. We then focus on how the generated code and run-time support interact to provide dynamic resources and to generate and service invocations. We also describe optimizations for certain operations. Measurements of the implementation's size and cost are given. The implementation has been in use since November 1985 and is currently being improved. Finally, we justify SR's syntax and semantics and examine how its mechanisms compare to other approaches to distributed programming. We also discuss how SR balances expressiveness, simplicity, and efficiency.
    • Issues in round harmony: Grounding, identity and their interaction.

      Hong, Sung-Hoon; Archangeli, Diana B.; Hammond, Michael; Demers, Richard (The University of Arizona., 1994)
      This dissertation examines the cross-linguistic patterns of "height-constrained" Round Harmony (RH), from the perspective of Grounding Condition Theory proposed by Archangeli and Pulleyblank (in press). The fundamental claim advanced here is that the attested patterns of RH are due to two conditions, (i) the grounded path condition R(oun)D/HI(gh), "if (+round) then (+high) " or "if (+round) then not (-high)", and (ii) the Phonological Identity Condition (PIC). The grounded condition RD/HI, motivated from the physiological correlation between lip rounding and tongue height (mediated by jaw opening), holds of the targets of rules, thereby restricting the application of RH to high vowel targets. The PIC, on the other hand, is proposed to characterize the contextual identity requirement for rules. Two important properties of the PIC are noted: (i) that it is a non-representational condition, and (ii) that identity referred to by the PIC is implemented as logical equivalence. The non-representational PIC is motivated from the cases of "nonadjacent" identity (i.e. the cases where contextual identity can be defined across a transparent element, e.g. Khalkha Mongolian RH), where a representational analysis based on OCP-induced fusion fails because it results in either illformed "gapped" representations or violation of the No-Crossing Line Convention. Further, the equivalence interpretation of identity is proposed to break away from otherwise mandatory rules of redundant feature insertion for cases like Yawelmani RH, where identity refers to both values of a feature. Drawing on these two conditions, this dissertation demonstrates that the observed patterns of height-constrained RH are correctly predicted by recognizing two factors, the rule types characterized by these conditions, and the way that these rule types are invoked by languages.