The development of multiple theoretical models and measures of impulsivity has led to inconsistent use of this term and disagreement regarding the most salient predictors of alcohol-related outcomes. The present study examined whether self-report and behavioral measures of impulsivity measure the same construct and how eight conceptually distinct facets of impulsivity relate to alcohol-related outcomes. Participants completed measures and tasks to assess alcohol use, alcohol problems, trait impulsivity, and behavioral impulsivity. The UPPS-P and behavioral measures of impulsivity were largely uncorrelated with each other. Negative urgency and alcohol use emerged as direct predictors of alcohol-related problems. Lack of premeditation demonstrated an indirect effect on alcohol-related problems. Results support previous research suggesting behavioral and self-report measures of impulsivity do not assess the same construct. Further, results suggest that negative urgency may be the most predictive of alcohol-related problems when accounting for self-report and behavioral components of impulsivity.

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Proof of Concept - An Academic LIMS application: The aim of this project is the creation of an open-source, freeware LIMS application that can be used in an academic setting as a teaching tool for both chemistry and computer science students. The LIMS package will combine an application, developed using VB.NET, to manage the data with other open-source or freeware programs such as MySQL and WEKA. The numerous commercial chemical informatics applications available are useful tools to learn how to manage data from a user's standpoint. However, they are not readily available to the average student, nor do they offer a great understanding into how they were developed from a programmer's frame of mind. There is a great void here that, if filled can greatly help the academic community.

Predicting tire performance on soft, fine-grained soils is required for many off-road explorations in the military, mining, agricultural, and earth-moving sectors. However, the mobility in deformable material is extremely challenging, especially in the presence of water. Although there is a significant amount of research on terrains such as sands, there is a lack of research on fine-grained soils. This research is part of a bigger project that presents a novel approach to improve the mobility of off-road vehicles on wet deformable soils. The approach integrates experimental data from small-scale soil testing, large-scale soil-tire interaction testing, and advanced physics-based numerical simulation techniques. In particular, this thesis attempts to characterize the clay-tire interface by conducting large-scale direct shear tests. In addition to clay-tire contact friction, the properties and strength parameters of the soft clay are determined by conducting various index properties and advanced tests. The testing program accounts for different stresses, loading conditions, and boundary conditions, decided taking into account real field conditions. The results from all these experiments will be used to calibrate and validate the material constitutive models required for the development of a mobility predictive numerical model. Overall, this study contributes to the development of more advanced and accurate terramechanics models that involve deformable terrains like soft clays. / Master of Science / The prediction of Vehicle mobility on soft, fine-grained soils is challenging due to the impact of soil behavior on mobility, which is not taken into account by traditional vehicle simulation software. However, as off-road exploration and resource extraction become increasingly important, particularly in military, agricultural, and earth-moving sectors, the study of vehicle mobility on deformable soils is inevitable. The difficulty in predicting tire performance on soft, fine-grained soils is due to the lack of proper experimental data and numerical modeling techniques that accurately characterize the interaction between soil and vehicle tires, known as "terramechanics." The study forms a constituent part of a broader project, which aims to integrate the experimental research data from small-scale soil testing, large-scale soil-tire interaction testing, and advanced physics-based numerical simulation techniques. The main contribution of this study is to investigate soil-tire interaction to determine the contact friction between the soil and tire by conducting large-scale direct shear tests. It also involves conducting basic index properties tests and advanced shear strength and compression tests. The results from all these tests contribute to developing more accurate soil-tire interaction models in terramechanics. Given the scarcity of research on large deformable terrains like soft clays, this study can make a significant contribution towards developing more advanced and accurate terramechanics models that involve deformable terrain, which can be useful in various applications.

This thesis describes the modifications made to the Cal Poly Thermal Science Laboratory’s steam turbine experiment. While the use of superheating or reheating is commonly used to increase efficiency in a Rankine cycle the methods prove unfeasible in a small scale project. For this reason, a mathematical model and proof of concept design using hydrostatic head generated by elevation and venturi ejection for use by the condenser is developed along with the equations needed to predict the changes to the system. These equations were used to create software to predict efficiency as well as lay down the foundation for future improvements of the system.

On the basis of a strong body of data, the Institute of Medicine currently recommends at least 60 minutes of exercise per day to prevent body weight gain overtime. Previous studies have shown that there is no compensatory increase in food intake with this dose of exercise. Ultimately, the brain decides whether to alter food intake. Surprisingly, no published studies have assessed the impact of exercise on brain activation. Using functional magnetic resonance imaging (fMRI) and an appetite questionnaire, we investigated the effects of a single bout of aerobic exercise on brain responses to visual food cues and subjective appetite responses. After an overnight fast, 30 (17M, 13W), healthy, habitually active subjects (22.0±3.8 years, 23.6±2.4 kg/m2, 44.3±8.3 mL∙kg-1∙min-1) either rested or exercised for 60 minutes, in a counterbalanced crossover design. Immediately after each condition, blood oxygen dependent levels were determined in response to visual food cues of different energy value during an fMRI scan. Exercise showed significantly greater activation (P < .005, uncorrected) in regions implicated in food inhibition (superior frontal gyrus, medial surface), and visual attention (precuneus, superior temporal gyrus, middle temporal gyrus and fusiform gyrus) regions. However, exercise did show a greater activation in a food reward region (medial orbitofrontal cortex). The rest condition only showed greater activation in a visual center (fusiform gyrus) and the midbrain. In addition, relative to no-exercise, subjective appetite responses were suppressed following the exercise bout. Taken altogether, these data suggest exercise may impact the brain in a direction expected to suppress food intake and increase food attention, which is in line with previous behavioral, biological and fMRI data. These findings may explain, at least partially, why aerobic exercise does not lead to a compensatory increase in food intake.

<p> This is a study of the groundwaters and their associated rocks and minerals from the Lac du Bonnet batholith at the Underground Research Laboratory (URL), Pinawa, Manitoba, to assess the water-rock interaction in crystalline rocks by using Sr, O and U-series isotopes. Emphasis is also placed on the development of the analytical techniques.</p> <p> A high precision analytical technique of U-series isotopes has been developed in this study by using solid-source mass spectrometry. A precision of better than 1% (2σ) is achieved in determining the 234U/238U and 230Th/234U ratios using 10^-8 g of U and 10^-11 g of 230Th. The potential applications of this method is demonstrated by dating small speleothem samples and the results agree well with those of α-spectrometry. This method also applies well to precise determination of the 234U/238U ratios in groundwaters and igneous rocks and minerals using small quantities of samples. However, precise measurements of 230Th in igneous rocks and minerals are limited by the large 232Th tail in the Th mass spectrum. Even better precision is achievable if pure Th spike is used.</p> <p> An ICP-MS isotope dilution method is also developed for fast and precise determination of Sr concentrations in groundwater samples. A precision of 1% is routinely achieved by taking into account the dead-time effect of the Channel Electron Multiplier (CEM) and the sample-to-spike ratios.</p> <p> The isotope results of both the groundwaters and the host rocks and minerals have revealed the processes of water-rock interaction and water mixing through the history of the batholith. Strontium isotope systematics of the rocks and their constituent minerals have shown that Sr loss occurred on whole-rock scale during both the high-temperature alteration (about 2300 Ma ago) and the low-temperature alteration which lasted at least 450 Ma. The Sr loss is most pronounced in plagioclase of altered samples. Uranium-series results indicate the disequilibrium of both whole-rock samples and minerals, and migration of U on whole-rock scale in, at least, the last million years.</p> <p> The Sr and O isotopic results have shown that the groundwaters from the three sub-horizontal, successively deeper fracture zones (FZ) have distinct isotopic signature: 87Sr/86Sr= 0.715 to 0.719 and 𝛿18O=-13o/oo for FZ-3; 87Sr/86Sr= 0.720 to 0.729 and 𝛿18O=-13 to -20o/oo for FZ-2; 87Sr/86Sr= 0.730 to 0.738 and 𝛿18O=-13 to -17o/oo for FZ-1. Uranium-series results show that all the groundwaters are highly enriched in 234U and the 234U/238U activity ratios range from 2.6 to 7.7. Mixing of three groundwaters is indicated by the Sr and O isotopes and the elemental chemistry. The three end-members are fresh surface water, the deep fresh (possibly glacial melt) groundwater and the deep saline groundwater.</p> <p> Comparison between the rocks and associated groundwaters shows that Sr isotopic equilibrium exists between plagioclase of altered samples and the groundwaters. This similarity indicates the vulnerable mineral phase control, such as plagioclase in this case, of the isotopic signatures, hence, chemistry of the groundwaters.</p> / Thesis / Master of Science (MSc)

No description available.

Nowadays, asphalt mixtures can be complex and have many ingredients to meet economic, performance, and/or environmental requirements. Economic and environmental factors have been driving performance in the positive direction for rutting, but the negative direction for brittleness, cracking, and overall durability. Recent research has also shown that two of the national standards to assess aging or effects of environmental factors (AASHTO T283 and R30) do not always simulate the amount of aging or behaviors mentioned in the documents. Also, these methods generally view one environmental effect at a time, and do not consider simultaneous environmental effects on aging (e.g. oxidation, moisture, freeze-thaw effects). However, pavements are exposed to combined environmental effects. As such, there is a lack of understanding of the combined environmental effects on asphalt pavement, and improve methods are needed for laboratory settings, resulting in less than optimal design and materials selection protocols. This dissertation focuses on investigating combined environmental effects of oxidation, moisture, and freeze-thaw. The dissertation includes four years of field aging of plant mixed asphalt mixtures containing no recycled materials and three different warm mix technologies that were also exposed to eight laboratory conditioning protocols including individual and combined environmental effects of oxidation, moisture and freeze-thaw to investigate mixture properties measured at high, intermediate, and low temperatures with several mixture tests that were complimented with tests on recovered binder. Major findings are summarized below: • Cantabro mass loss captured individual and combined effects damage in laboratory and field conditions better than other mixture testing utilized herein and was recommended for mixture assessment. • Laboratory conditioning protocols with combined effects were the only ones able to consistently represent four or more years of field aging in the Mississippi climate. • Field aging of laboratory compacted specimens in PVC sleeves did not fully represent field aging of field placed pavement. Temperature and moisture conditions varied between the two cases. • Use of Cantabro mass loss and laboratory conditioning consisting of hot air, hot water, and freeze-thaw conditions was shown to provide combined effects improvements relative to at least some typical practices. Guidance was provided on how to use these tools to assess combined effects.

Asphalt concrete pavements on commercial airports in the United States are constructed according to the Federal Aviation Administration Advisory Circular 150/5370-10B, Item P-401, “Plant Mix Bituminous Pavements.” This specification does not provide guidance for using the Superpave gyratory compactor in the design of asphalt mixtures. This thesis describes a laboratory study of hot mix asphalt (HMA) mix design for airport pavements that uses the Superpave gyratory compactor. These recommendations are based on comparisons of volumetric property measurements of HMA mixtures compacted using Marshall compaction and Superpave gyratory compaction.