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Invited commentary on Stewart and Davis " 'Big data' in mental health research-current status and emerging possibilities"
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Aspects of phonology and morphology of Teotepec eastern Chatino
textThis dissertation is a description of aspects of the phonetics, phonology and morphology of Teotepec Chatino (ISO 639-3 identifier: cya; here abbreviated as TEO), an indigenous language spoken by approximately 3800 people in the Sierra Madre del Sur, Oaxaca, Mexico. This work presents a synchronic description of the language based on data collected in the eld over the course of six eld trips totaling eighteen months. This investigation is based on a corpus of thirty hours of transcribed and analyzed texts of naturally occurring speech, narratives, data gathered during elicitation sessions, and an expansion of my earlier grammatical sketch (2011). The final result is a description of the phonology and phonetics of tone and some of the morphological processes that exist in the grammar. The focus of this work is to describe the structure of the language produced by native Teotepec speakers and how it is used in an array of contexts. This is reflected in a rich body of procedural texts, conversations, speeches, rants, polemics, prayers, and narratives. These texts are the basis for the description of how the language encodes speakers' knowledge about the world and their greater context. This work arrives at a description of the details of the language while also making broader generalizations about these details. It is not possible that this work cover all aspects of the phonology, phonetics, morphology and so part of the focus has been to capture particular facets of the language and explain them in a way that is detailed while broad enough to be useful to as many as audiences as possible. This includes scholars interested in typology, tone languages, historical linguistics of Otomanguean, linguistic anthropology, anthropology, and the history and culture of the Chatinos, southern Oaxaca and Mesoamerica. The dissertation is written in English; however, I often create grammatical write-ups and practical pedagogical materials for a Spanish literate audience. Materials for TEO have been and will continue to be made available to Spanish and English speakers in order to reach an audience that includes, but is not limited to, members of the community, local and regional educators and literacy efforts, and scholars engaged in the study of Chatino language and linguistics. The approach to this work is data-driven and text-based. It is written in basic descriptive terms, as outlined in Payne (1997); Shopen (2007); Dixon (2010), and Haspelmath (2010). In this way the writing is carried out with fewer aprioristic notions about the language. The goal is to describe the language in its own terms. Thus the researcher is open to discover completely new, unexpected phenomena, can be guided by the data and their own thinking (Haspelmath, 2010).Linguistic
The Crystal and Molecular Structure of Ovalene, Perylene and Octamethylnaphthalene
Described in this thesis are the results of research on three main problems. These three problems are separated into Parts I, II and III, which contain reports on investigations into the crystal and molecular structures of ovalene, perylene and octamethylnaphthalene respectively, by means of X-ray diffraction methods. The appendix contains a short account of the crystal structure of benzfurazane oxide. Part I. The crystal and molecular structure of ovalene has been determined by quantitative X-ray analysis. The monoclinic crystals, space group P21/a , have two centro-symmetrical molecules of C32 H14 per unit cell, and the structure resembles that of coronene. The cell dimensions of a = 19.47A, b = 4.70A, c = 10.12A and beta = 105.
Utilization of LiDAR Technology to Assess Vertical Clearances of Civil Infrastructure
The issue of vertical clearances along highway systems impact the functionality of the road network. Extracting current routing clearances for each structure can be a challenging and hazardous task. Pavement changes and roadway rehabilitation projects can alter roadway geometry, complicating efforts to maintain accurate clearance databases. Vertical clearance measurements may vary from one lane to another beneath overhead structures and are often difficult to obtain due to high traffic volumes. Inherently, traditional methods that are used to obtain the measurements routinely impede the flow of traffic and subject workers to dangerous environments. This study will examine the use of a Mobile LiDAR system and its applicability and accuracy to obtain vertical clearances on bridge structures. Further, the study will investigate the impact of utilizing a Mobile LiDAR system on traffic disruption and worker safety. The measurements extracted from LiDAR point clouds are compared to measurements obtained from traditional techniques using a laser tape meter and total station. Results will be analyzed to assist in quantifying the potential error between field and LiDAR measurements. Furthermore, the impact on work zone safety and traffic disruption is investigated. The results obtained from this study can be used to help identify the most effective method to extract infrastructure clearances and aid in future assessments
Temperature dependent carrier lifetime studies of Mo in crystalline silicon
The capture cross sections of both electronsσn and holes σp were determined for interstitialmolybdenum in crystalline silicon over the temperature range of −110 to 150 °C. Carrier lifetimemeasurements were performed on molybdenum-contaminated silicon using a temperature controlled photoconductance instrument. Injection dependent lifetime spectroscopy was applied at each temperature to calculate σp and σn. This analysis involved a novel approach that independently determined the capture cross sections at each temperature assuming a known defect density and thermal velocity. Since the energy state is in the lower half of the bandgap, the determination of σp is unaffected by the defect energy at all temperatures, and σp is found to decrease with temperature in a fashion consistent with excitonic Auger capture. At temperatures below 0 °C, the determination of σn is also unaffected by the defect energy due to the suppression of thermal emission, and σn decreases with temperature as well. It is shown that a projection of σn to higher temperature suggests the defect has an energy of 0.375 eV above the valance band edge of silicon.D.M. likes to thank the Australian Research Council for
fellowship and G.C. likes to thank “CrystalClear Integrated
Project” Contract No. SES6-CT_2003-502583 funded by
the European Commission
The U-band Galaxy Luminosity Function of Nearby Clusters
Despite the great potential of the U-band galaxy luminosity function (GLF) to
constrain the history of star formation in clusters, to clarify the question of
variations of the GLF across filter bands, to provide a baseline for
comparisons to high-redshift studies of the cluster GLF, and to estimate the
contribution of bound systems of galaxies to the extragalactic near-UV
background, determinations have so far been hampered by the generally low
efficiency of detectors in the U-band and by the difficulty of constructing
both deep and wide surveys. In this paper, we present U-band GLFs of three
nearby, rich clusters to a limit of M_U=-17.5 (M*_U+2). Our analysis is based
on a combination of separate spectroscopic and R-band and U-band photometric
surveys. For this purpose, we have developed a new maximum-likelihood algorithm
for calculating the luminosity function that is particularly useful for
reconstructing the galaxy distribution function in multi-dimensional spaces
(e.g., the number of galaxies as a simultaneous function of luminosity in
different filter bands, surface brightness, star formation rate, morphology,
etc.), because it requires no prior assumptions as to the shape of the
distribution function.
The composite luminosity function can be described by a Schechter function
with characteristic magnitude M*_U=-19.82+/-0.27 and faint end slope
alpha_U=-1.09+/-0.18. The total U-band GLF is slightly steeper than the R-band
GLF, indicating that cluster galaxies are bluer at fainter magnitudes.
Quiescent galaxies dominate the cumulative U-band flux for M_U<-14. The
contribution of galaxies in nearby clusters to the U-band extragalactic
background is <1% Gyr^-1 for clusters of masses ~3*10^14 to 2*10^15 M_solar.Comment: 44 pages, 11 figures, accepted for publication in Ap
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