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Experimental Investigation into the Thermal and Magmatic Evolution of Mercury
No full textDuring the time that the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft was in orbit around the innermost planet, new and exciting results regarding the planets structure, chemical makeup, and diverse surface were revealed, confirming that Mercury is a geochemical endmember among the terrestrial planets. Data from this mission, more specifically data from the X-Ray Spectrometer and Gamma-Ray Spectrometer onboard MESSENGER, has been used to provide insight into the thermal and magmatic evolution of Mercury. This dissertation consists of five chapters that, as a whole, have substantially increased our knowledge about Mercury through a high pressure and high temperature experimental investigation. First, we identified nine distinct geochemical regions that have characteristic major element compositions. We computed silicate and sulfide mineralogy of these regions and petrologically classified them according to IUGS specifications. The diversity of the rocks and minerals on Mercury was then compared to other planetary bodies revealing the wide range in diversity of the mercurian surface. Second, we conducted sink-float experiments on a melt composition similar to the composition of the largest volcanic field on the planet to provide insight into crust formation on Mercury. These results suggested a primary floatation crust composed of graphite is possible given a magma ocean event on Mercury. Third, we experimentally determined the phase assemblages associated with the largest volcanic field on the planet. From this data we were able to provide insight into eruption scenarios that produced the northern volcanic plains on Mercury. Fourth, we determined the sulfide concentration at sulfide saturation in mercurian-like melts by conducting sulfide solubility experiments on a synthetic rock composition matching the northern volcanic plains. These results indicated that the high amounts of sulfur on the surface of Mercury measured by MESSENGER are a direct consequence of the low oxygen fugacity of the planet, which allowed transport of S towards the surface in reducing melts which have a higher carrying capacity for S than oxidized melts. Finally, we investigated the carbon concentration at graphite saturation in Fe-rich metals with various amounts of Si to determine the amount of C that would be soluble in the mercurian core as a function of core composition and temperature. The results of this dissertation provide important information regarding the evolution of Mercury from its primary magma ocean event to the current state of the planet.New Mexico Space Grant Consortium, NASA Earth and Space Sciences Fellowship, NASA Cosmochemistry program, Department of Earth and Planetary Sciences summer scholarship fundsEarth and Planetary SciencesDoctoralUniversity of New Mexico. Dept. of Earth and Planetary SciencesMcCubbin, FrancisAgee, CarlChabot, NancyFischer, TobiasZiegler, Kare
A Comparison of Maximal Syllable Structure in Four Linguistic Areas
No full textResearch on areal linguistics provides ample evidence that languages in contact situations may come to share grammatical features that cannot be explained ontogenetically (Campbell 1997b, Matras 2011). In terms of phonology, the literature suggests that languages in prolonged contact develop similar segmental and suprasegmental characteristics (e.g. Aikhenvald & Dixon 2001, Curnow 2001, Muysken 2008, Thomason 2001). However, the effects of contact-induced change on deeper phonological structure such as syllable patterns remain largely unexplored. This study aims to investigate the claim that languages in intense contact situations such as those in linguistic areas are subject to borrowing not only individual phonemes but also phonological structure (Thomason & Kaufman 1988). Specifically, it looks at maximal syllable shape in languages belonging to four established Sprachbünde: the Caucasus Area (Chirikba 2008) in Europe, the Northwest Coast Area (Campbell 1997a) and the Pueblo Area (Bereznak 1995) in North America and the Southern Cone Area (Klein 1992) in South America.
Maximal syllable shape is the syllable type that contains the most possible segments in onset and coda positions, for instance CCCVCCCC in an English word like ‘strengths’ [stɹeŋkθs]. A core phonological characteristic of languages, maximal syllable shape has indeed served as a tool to categorize languages typologically (e.g. Maddieson 2013). Furthermore, studies on loan phonology show that syllabic patterns in borrowings are consistently adapted to a language’s native syllable structure (e.g. Peperkamp 2004). At the same time, there is evidence that even this property may be subject to contact- induced change (Matras & Sakel 2007), granted there is a large enough influx of loan words (Aikhenvald & Dixon 2007, Muysken 2008). Thus, the literature suggests that maximal syllable shape constitutes a solid parameter to examine language convergence under intense contact.
Following a top-down approach (Muysken 2008), the study presented here examined the maximal syllable shape in every language for which data were available in each of the four linguistic areas under investigation. Languages were compared within a single Sprachbund and, with the exception of isolates, measured against related languages elsewhere as a control. The data discussed here were obtained from three sources: reference grammars, a database of phonotactic structure (Donohue et al. 2013) and a large phonological database with information on syllable patterns (Maddieson et al. 2014-2016).
Results suggest that despite centuries of contact and a possibly large influx of borrowings, languages belonging to different families within the four Sprachbünden show little similarity in terms of maximal syllable structure. Rather, it is demonstrated that genetic affiliation is the most decisive factor in determining these patterns. These findings are novel in terms of providing an insight into the impact of language contact on phonological systems, a domain that still deserves attention in areal linguistics. Furthermore, they have implications to the matter vs. pattern hypothesis (Sakel 2007) in that it shows that syllabic patterns mirror genetic affiliation despite considerable borrowing (matter) from languages in a same area
Stable isotopes in atmospheric water vapour from Mauna Loa, Hawaii, 2016-2017
No full textThe isotopic composition of atmospheric water vapor (1H216O, H218O, and 1H2H16O) was continuously measured at the National Oceanic and Atmospheric Administration (NOAA) Mauna Loa Observatory (MLO) from April 8, 2016 through March 13, 2017 using Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS). The dataset has been carefully corrected for humidity-dependent biases and calibrated against the international VSMOW-SLAP scale to provide a precise, continuous, nearly yearlong dataset from a dynamic subtropical setting. The measurements are provided with 15-minute and 6-hourly resolution.This work was partially supported by NSF-AGS award 1158582 and by the University of New Mexico. This project was supported as part of a NOAA Global Monitoring Division cooperative agreement, and we thank the staff of the Mauna Loa Observatory for their assistance
Development of Soft-Matter Delivery Systems: Coupling pH Responsive Polymers to Porous Silica Particles
No full textThis work investigates polymeric coating of evaporated induced self-assembly (EISA) mesoprous silica nanoparticles for potential use in controlled drug release and therapeutics. As demonstrated here, lipid bilayer coatings can be easily replaced with different polymer analogs allowing for dynamic response to environmental stimuli. In addition to coupling commercially available diblock polymers we synthesized and characterized a unique dual hydrophilic pH responsive diblock copolymer, PEO-PAA. This hybrid polymeric-nanoparticle system drastically improves targeting and release capabilities through the modular ability to couple multiple different polymers. Furthermore, this work is supported by an improved method to form and study giant polymer vesicles (pGVs)This work was sponsored by the Center for Integrated Nanotechnologies: user proposal C2014B0059, the Advanced Materials Laboratory, and in part by BES-MS
Navigating Institutional Racism and Improving Campus Climate: Culturally Diverse Graduate Students Breaking the Mold
No full textInstitutions are widget factories. They have become the handmaiden of the status quo, cranking out clinicians and researchers who view the world through a universal lens. A universal perspective to the understanding of human health and education leads to the assumption that all humans are the same and fails to acknowledge human diversity. We know this prac tice to be harmful; institutions, researchers and healthcare providers have a history of discounting the importance of culture, race and ethnicity resulting in harm to students, patients and humankind. A diversity of perspectives promote ingenuity and scientific progress. We need to train diverse students, clinicians, and researchers who will engage in society with originality, passion, and responsiveness to traditionally marginalized groups
Paper, Abstracts, and Proceedings of the Eleventh Annual Himalayan Policy Research Conference
No full textThis volume brings together papers and abstracts from the Eleventh Annual Himalayan Policy Research Conference (HPRC) held at the Madison Concourse Hotel and Governor's Club in Madison, WI. The event was a pre-conference proceeding of the 45th South Asian Conference at the University of Wisconsin, Madison on October 20, 2016. Session topics included Geopolitical Conflicts and Human Rights, Education, Health and Social Safety Nets,Developmental Issues, and Agro-forestry, Energy and Environmental Issue
ANALYSIS OF BRAZILIAN SPLIT CYLINDER USING THE STATE BASED PERIDYNAMIC LATTICE MODEL
No full textConcrete members deform discontinuously in the form of cracks and fracture. Continuum mechanics, which has dominated the field of solid mechanics over the years, does not handle such discontinuities. A material, as defined by continuum mechanics is that which is continuous and fills the space it occupies. Although this is a reasonable assumption for metals, it is an unrealistic notion for concrete. Stewart Silling invented peridynamics, which involves nonlocal solid modelling upon a continuous material space. Walter Gerstle developed a practical application of the peridynamic model for solid mechanics called the state-based peridynamic lattice model (SPLM). This approach involves material modelling with a finite number of interacting lattice particles rather than a continuum. The advantage of SPLM lies in its ease of computational implementation. SPLM is used in this thesis to analyze the very widely used Brazilian split cylinder test in estimating the uniaxial tensile strength of concrete. Additionally, the direct tension test and the modulus of rupture test are modelled to better understand the tensile strength of concrete and concrete behavior.Civil EngineeringMastersUniversity of New Mexico. Dept. of Civil EngineeringGerstle, WalterYu-Lin, ShenReda Taha, Mahmou
Inhaled multiwalled carbon nanotubes induce systemic inflammation and endothelial dysfunction via MMP-9 induction
No full textAssessing the mechanisms underlying adverse cardiovascular effects induced by inhaled toxins presents a substantial research challenge. We propose that blood carries an as yet unknown “inflammatory potential” consisting of modified proteins or other biomolecules and reaction byproducts that affects a pathological bioactivity which can be assessed using naïve endothelial cells and blood vessels. The approach involves applying serum from exposed animals to cultured primary endothelial cells or ex vivo isolated arteries.
Mice were exposed to multi-walled carbon nanotubes (MWCNT; 0, 10 or 40 μg) or other pollutants via pharyngeal aspiration and serum was collected at 4 and 24 h post-exposure. Serum from exposed mice increased endothelial cell surface vascular cell adhesion molecule-1 (VCAM-1) and intracellular adhesion molecule-1 (ICAM-1) expression and proinflammatory transcripts, and decreased ATP-stimulated nitric oxide (NO) production. The functional impact of this loss of NO bioavailability was confirmed via myography, in which serum from pollutant-exposed mice significantly impaired vasodilation to acetylcholine. In addition, serum from pollutant-exposed mice reduced cell migration in a traditional scratch assay experiment. In vivo MWCNT exposure was able to both increase the permeability of the Blood Brain Barrier (BBB), as well as induce transcription of pro- inflammatory cytokines in the hippocampus and frontal cortex regions of the brain. This affect was abolished with the treatment of fasudil, or the absence of CD36. There was also evidence of astrocyte activation in the short and microglia activation at 24 hours. CD 36 has also been identified as playing a key role in mediating loss of vasodilatory properties ex vivo.
In conclusion, pulmonary exposure to MWCNT dynamically alters circulating factors, which promotes endothelial cell activation, decreased NO bioavailability, and altered functionality all directionally predicting adverse cardiovascular outcomes.NIHBiomedical SciencesDoctoralUniversity of New Mexico. Biomedical Sciences Graduate ProgramCampen, MatthewBurchiel, ScottWalker, MaryKanagy, NancyErdely, Aaro