The Mousterian: A Study of a Paleolithic Tool Industry

This paper is designed to be a study of a Paleolithic flint industry: the Mousterian of Neanderthal man. It is a detailed analysis of the types and styles of flintwork which this early man produced. It will detail tool types, chipping techniques, regional varieties, and outside influences. It will explore the extent to which Neanderthal man worked in gone and how the Mousterian flint forms are mirrored in this other medium. It will shoe how the Mousterian developed and how it was influenced by earlier and contemporary industries

Changes in Vitrinite Reflectance and Liptinite Fluorescence with Increasing Rank in Dispersed Organics in the Illinois Basin and its Environmental, Economic, and Political Impacts

Vitrinite reflectance and spectral fluorescence are commonly used together to determine the rank and thermal maturity of shale samples. Although vitrinite is not commonly found in the New Albany Shale, solid bitumen is found in significant amounts; reflectance of solid bitumen provides another method to determine maturity of these samples. The purpose of this study was to compare the vitrinite reflectance and spectral fluorescence of liptinites to determine the thermal maturity of the New Albany Shale, which can benefit those tasked in the industry who determine the oil and gas potential of these source rocks. Establishment of a relationship between vitrinite reflectance and fluorescence can help create another rank parameter (alginite fluorescence) to determine the thermal maturity in the basin. This methodology for determining the hydrocarbon potential can also impact other areas of the country where black shales are exploited, including Eastern Kentucky (Ohio Shale) and North Dakota and Montana (Bakken Shale). This could potentially improve assessments of source rocks in terms of oil or gas, saving companies from potential costly mistakes. The other purpose of this study was to look at the potential political, economic, and environmental impacts that result from the extraction of oil and gas by the process of hydraulic fracturing. Evaluating the impacts of hydraulic fracturing in the State of Illinois allows for a better understanding of how lawmakers, resource companies, and scientists can contribute to a broader view of the regional effects of this activity

Analysis of light curves from the 2003 Nov 14 occultation by Titan of TYC 1343-1855-1

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 17-18).We observed a stellar occultation by Titan on 2003 November 14 from La Palma Observatory using ULTRACAM with three Sloan filters: u', g', and i' (358, 487, and 758 nm, respectively). The occultation probed latitudes 2°S and 1°N during immersion and emersion, respectively. A prominent central flash was present in only the i' filter, indicating wavelength-dependent atmospheric extinction. We inverted the light curves to obtain six lower-limit temperature profiles between 335 and 485 km (0.04 and 0.003 mb) altitude. The i' profiles agreed with the temperature measured by the Huygens Atmospheric Structure Instrument [Fulchignoni, M., and 43 colleagues, 2005. Nature 438, 785-791] above 415 km (0.01 mb). The profiles obtained from different wavelength filters systematically diverge as altitude decreases, which implies significant extinction in the light curves. Applying an extinction model [Elliot, J.L., Young, L.A., 1992. Astron. J. 103, 991-1015] gave the altitudes of line of sight optical depth equal to unity: 396 ± 7 km and 401 ± 20 km (u' immersion and emersion); 354 ± 7 km and 387 ± 7 km (g' immersion and emersion); and 336 ± 5 km and 318 ± 4 km (i' immersion and emersion). Further analysis showed that the optical depth follows a power law in wavelength with index 1.3 ± 0.2. We present a new method for determining temperature from scintillation spikes in the occulting body's atmosphere. Temperatures derived with this method are equal to or warmer than those measured by the Huygens Atmospheric Structure Instrument. Using the highly structured, three-peaked central flash, we confirmed the shape of Titan's middle atmosphere using a model originally derived for a previous Titan occultation [Hubbard, W.B., and 45 colleagues, 1993. Astron. Astrophys. 269, 541-563].by Angela M. Zalucha.S.M

The Role of GLP-1 in the Regulation of Metabolism and Immune Responses

Glucagon-like peptide-1 (GLP-1) is encoded by the preproglucagon gene (Gcg) and expressed in the intestine, pancreas, and central nervous system (CNS). Activation of GLP-1 receptors (GLP-1R) on pancreatic alpha-cells induces insulin secretion in a glucose-dependent manner while activation of CNS GLP-1Rs suppress feeding. Thus, Gcg-derived peptides play an important role in gluco- and body weight regulation, and GLP-1 has been implicated in the success of bariatric surgery. GLP-1 agonists are an effective treatment of type 2 diabetes mellitus (T2DM) and obesity. The predominant source of circulating GLP-1 is the intestine, but the alpha-cell becomes an important source when the islet is metabolically stressed. Further, plasma GLP-1 is increased in T2DM patients in response to inflammation. Nutrient-stimulated GLP-1 functions as an incretin, however, the function of GLP-1 during inflammation is unknown. My dissertation proposes that during inflammation, GLP-1 plays a metabolic role, functioning to regulate glucose levels and food intake, and an immunologic role, functioning to regulate inflammation. I examined the metabolic and immunologic role of Gcg under inflammatory conditions. Using a combination of high-fat diet (HFD)-induced obesity and a mouse model of tissue-specific Gcg expression, I explored the function of GLP-1 in response to inflammation by administering lipopolysaccharide (LPS), a well-established tool for inducing inflammation. LPS is a known anorectic agent that also alters glucose homeostasis; both functions of GLP-1. I hypothesized that HFD would exacerbate physiological responses to LPS including increased plasma GLP-1, decreased blood glucose levels, and increased sickness-induced anorexia, as well as systemic inflammatory responses including increased plasma cytokines. Indeed, HFD did increase plasma pro-inflammatory cytokines, and GLP-1 levels in response to LPS and this was associated with greater anorexia in HFD-fed animals. In the next set of studies, I tested whether GLP-1 secreted from either the pancreas or intestine was directly regulating feeding and glucose responses to LPS. I hypothesized that increases in circulating GLP-1, primarily from the pancreas, were necessary for feeding and glucose responses to LPS. I found that while both pancreatic and intestinal Gcg contribute to circulating levels of GLP-1 after LPS, the availability of either source of GLP-1 had no impact on glucoregulatory or feeding responses. Because pancreatic GLP-1 is the more novel contributor to circulation, I investigated the impact of Gcg on pancreatic inflammation. I found that 24h after LPS, whole-body chow-fed Gcg Null animals had increased macrophage accumulation in the pancreas. I saw a similar trend in HFD-fed Gcg Null mice. Using a GLP-1R reporter mouse, I found that macrophages isolated from the pancreas, but not the bone marrow, express GLP-1R. These data suggest that pancreatic GLP-1 directly regulates local macrophage responses to inflammation. I conclude that under severe inflammatory conditions, GLP-1 plays an immunologic rather than metabolic role in the pancreatic responses to LPS, through direct macrophage regulation. This dissertation indicates a new role for GLP-1 signaling to pancreatic macrophages in response to inflammation. Future studies will explore the impact of this increased macrophage accumulation on long-term pancreatic function. In fact, my preliminary data demonstrate that IP glucose tolerance was impaired 2 weeks following LPS. This lasting impact of inflammation on pancreatic function points to a new use of GLP-1 agonists to protect pancreatic tissue during severe inflammation such as sepsis, or more recently, COVID-19.PHDNutritional SciencesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/169674/1/emdavi_1.pd

The effect of topography on the Martian atmospheric circulation and determining Pluto's atmospheric thermal structure from stellar occultations

Thesis (Ph. D. in Atmospheric Science)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2010.Cataloged from PDF version of thesis.Includes bibliographical references (p. 143-152).Previous work with Mars General Circulation Models (MGCMs) has shown that the north-south slope in Martian topography causes asymmetries in the Hadley cells at equinox and in the annual average. To quantitatively solve for the latitude of the dividing streamline and poleward boundaries of the cells, the Hadley cell model of Lindzen and Hou [1988, J. Atmos Sci. 45, 216-2427] was modified to include topography. The model was thermally forced by Newtonian relaxation to an equilibrium temperature profile calculated with daily averaged solar forcing at constant season. Two sets of equilibrium temperatures were considered that either contained the effects of convection or did not. When convective effects were allowed, the presence of the slope component shifted the dividing streamline upslope, qualitatively similar to a change of season in the original Lindzen and Hou [1988 (flat) model. The modified model also confirmed that the geometrical effects of the slope are much smaller than the thermal effects of the slope on the radiative-convective equilibrium temperature aloft. The results are compared to a simple MGCM forced by Newtonian relaxation to the same equilibrium temperature profiles, and the two models agree except at the winter pole near solstice. The simple MGCM results for radiative-convective forcing also show an asymmetry between the strengths of the Hadley cells at northern summer and northern winter solstices. The Hadley cell weakens with increasing slope steepness at northern summer solstice, but has little effect on the strength at northern winter solstice. In the second part, a radiative-conductive model from Strobel et al. [1996, Icarus 120, 266-289] was used to least-squares fit Pluto stellar occultation light curve data. This model predicted atmospheric temperature based on surface temperature, surface pressure, surface radius, and methane and carbon monoxide mixing ratios, from which model light curves were able to be calculated. The model improves upon previous techniques for deriving Pluto's atmospheric thermal structure from stellar occultation light curves by calculating temperature (as a function of height) caused by heating and cooling by species in Pluto's atmosphere, instead of a general assumption that temperature follows a power law with height or some other idealized function. Fits were able to be performed for model surface radius, surface pressure, and methane mixing ratio with one of the 2006 datasets and for surface pressure and methane mixing ratio for other datasets from the years 1988, 2002, 2006, and 2008. It was not possible to fit for carbon monoxide mixing ratio and surface temperature because the light curves are not sensitive to these parameters. The model surface radius, under the assumption of a stratosphere only (i.e. no troposphere) model and radiative equilibrium, was determined to be 1180 +20/-10 kin, where the error bars are those from the formal least-squares fit and errors on the closest approach distance. The methane mixing ratio results are more scattered with time and are in the range of 0.18% to 1.78%. The surface pressure results show an increasing trend with time, although it is not as dramatic as the factor of 2 from previous studies. Finally, I demonstrate with a preliminary Pluto general circulation model the importance of the effect of atmospheric circulation on temperature and surface pressure.by Angela Marie Zalucha.Ph.D.in Atmospheric Scienc

Incorporation of a gravity wave momentum deposition parameterization into the Venus Thermosphere General Circulation Model (VTGCM)

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96657/1/jgre20038.pd