338 research outputs found
The Basics of American Government
Newly revised, The Basics of American Government offers a comprehensive overview of the American political system for students taking introductory courses in American national government and combines the best aspects of both a traditional textbook and a reader. The Basics of American Government is a collaborative effort among eight current and one former faculty members in the Department of Political Science & Criminal Justice at the University of North Georgia. Most of its chapters offer a piece of original scholarship as a case study bolstering the material in the chapter. Additionally, most chapters present a civic engagement-type exercise and discussion questions that are challenging and engaging, and help foster student participation in the political system. The purpose of this book is to offer a no-frills, low-cost, yet comprehensive overview of the American political system for students taking introductory courses in American national government.
A print version of this book is available for $27.99.
Contact the University of North Georgia Press for details and ordering information. [email protected] | 706-864-1556https://digitalcommons.northgeorgia.edu/books/1004/thumbnail.jp
Trends in stream nitrogen concentrations for forested reference catchments across the USA
To examine whether stream nitrogen concentrations in forested reference catchments have changed over time and if patterns were consistent across the USA, we synthesized up to 44 yr of data collected from 22 catchments at seven USDA Forest Service Experimental Forests. Trends in stream nitrogen presented high spatial variability both among catchments at a site and among sites across the USA. We found both increasing and decreasing trends in monthly flow-weighted stream nitrate and ammonium concentrations. At a subset of the catchments, we found that the length and period of analysis influenced whether trends were positive, negative or non-significant. Trends also differed among neighboring catchments within several Experimental Forests, suggesting the importance of catchment-specific factors in determining nutrient exports. Over the longest time periods, trends were more consistent among catchments within sites, although there are fewer long-term records for analysis. These findings highlight the critical value of long-term, uninterrupted stream chemistry monitoring at a network of sites across the USA to elucidate patterns of change in nutrient concentrations at minimally disturbed forested sites
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Computational investigation of noble gas adsorption and separation by nanoporous materials.
Molecular simulations are used to assess the ability of metal-organic framework (MOF) materials to store and separate noble gases. Specifically, grand canonical Monte Carlo simulation techniques are used to predict noble gas adsorption isotherms at room temperature. Experimental trends of noble gas inflation curves of a Zn-based material (IRMOF-1) are matched by the simulation results. The simulations also predict that IRMOF-1 selectively adsorbs Xe atoms in Xe/Kr and Xe/Ar mixtures at total feed gas pressures of 1 bar (14.7 psia) and 10 bar (147 psia). Finally, simulations of a copper-based MOF (Cu-BTC) predict this material's ability to selectively adsorb Xe and Kr atoms when present in trace amounts in atmospheric air samples. These preliminary results suggest that Cu-BTC may be an ideal candidate for the pre-concentration of noble gases from air samples. Additional simulations and experiments are needed to determine the saturation limit of Cu-BTC for xenon, and whether any krypton atoms would remain in the Cu-BTC pores upon saturation
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Language support for immigrant children: a study of state schools in the UK and US
In recent decades, immigrants, refugees and asylum seekers have sought a new way of life in large numbers, often leaving their countries of origin behind in search of places that offer a better way of life. The purpose of this study was to investigate how elementary and middle school students in state schools in Reading, England (primarily speakers of Asian languages), and Richmond, Virginia (primarily speakers of Spanish), were supported academically, when most children’s first language was not English. The authors were interested in exploring whether or not there were cultural or structural differences in the way each country helped or hindered these students as they progressed through the school systems. Three UK schools in a district of approximately 100,000 and three US schools in a district of approximately 250,000 were the focus of this exploration from 2000 to 2003. Findings indicated that there were cultural and legislative differences and similarities. Teachers and administrators in both countries attempted to provide services with limited and sometimes diminishing resources. Community support varied based on resources, attitudes toward various ethnic groups, and the coping strategies adopted by these groups in their new environments. Marked differences appeared with regard to the manner in which assessments took place and how the results were made available to the public
Toward Rational Design of Metal-Organic Frameworks for Sensing Applications: Efficient Calculation of Adsorption Characteristics in Zero Loading Regime
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Trends in stream nitrogen concentrations for forested reference catchments across the USA
To examine whether stream nitrogen concentrations in forested reference catchments have
changed over time and if patterns were consistent across the USA, we synthesized up to 44 yr
of data collected from 22 catchments at seven USDA Forest Service Experimental Forests.
Trends in stream nitrogen presented high spatial variability both among catchments at a site
and among sites across the USA. We found both increasing and decreasing trends in monthly
flow-weighted stream nitrate and ammonium concentrations. At a subset of the catchments,
we found that the length and period of analysis influenced whether trends were positive,
negative or non-significant. Trends also differed among neighboring catchments within several
Experimental Forests, suggesting the importance of catchment-specific factors in determining
nutrient exports. Over the longest time periods, trends were more consistent among
catchments within sites, although there are fewer long-term records for analysis. These
findings highlight the critical value of long-term, uninterrupted stream chemistry monitoring
at a network of sites across the USA to elucidate patterns of change in nutrient concentrations
at minimally disturbed forested sites.Keywords: forested catchment, nitrate, trends, stream, reference catchments, ammoniumKeywords: forested catchment, nitrate, trends, stream, reference catchments, ammoniu
Interaction between the microbiome and TP53 in human lung cancer.
BACKGROUND: Lung cancer is the leading cancer diagnosis worldwide and the number one cause of cancer deaths. Exposure to cigarette smoke, the primary risk factor in lung cancer, reduces epithelial barrier integrity and increases susceptibility to infections. Herein, we hypothesize that somatic mutations together with cigarette smoke generate a dysbiotic microbiota that is associated with lung carcinogenesis. Using lung tissue from 33 controls and 143 cancer cases, we conduct 16S ribosomal RNA (rRNA) bacterial gene sequencing, with RNA-sequencing data from lung cancer cases in The Cancer Genome Atlas serving as the validation cohort.
RESULTS: Overall, we demonstrate a lower alpha diversity in normal lung as compared to non-tumor adjacent or tumor tissue. In squamous cell carcinoma specifically, a separate group of taxa are identified, in which Acidovorax is enriched in smokers. Acidovorax temporans is identified within tumor sections by fluorescent in situ hybridization and confirmed by two separate 16S rRNA strategies. Further, these taxa, including Acidovorax, exhibit higher abundance among the subset of squamous cell carcinoma cases with TP53 mutations, an association not seen in adenocarcinomas.
CONCLUSIONS: The results of this comprehensive study show both microbiome-gene and microbiome-exposure interactions in squamous cell carcinoma lung cancer tissue. Specifically, tumors harboring TP53 mutations, which can impair epithelial function, have a unique bacterial consortium that is higher in relative abundance in smoking-associated tumors of this type. Given the significant need for clinical diagnostic tools in lung cancer, this study may provide novel biomarkers for early detection
Water Vapor on Betelgeuse as Revealed by TEXES High-Resolution 12 Micron Spectra
The outer atmosphere of the M supergiant Betelgeuse is puzzling. Published
observations of different kinds have shed light on different aspects of the
atmosphere, but no unified picture has emerged. They have shown, for example,
evidence of a water envelope (MOLsphere) that in some studies is found to be
optically thick in the mid-infrared. In this paper, we present high-resolution,
mid-infrared spectra of Betelgeuse recorded with the TEXES spectrograph. The
spectra clearly show absorption features of water vapor and OH. We show that a
spectrum based on a spherical, hydrostatic model photosphere with T_eff = 3600
K, an effective temperature often assumed for Betelgeuse, fails to model the
observed lines. Furthermore, we show that published MOLspheres scenarios are
unable to explain our data. However, we are able to model the observed spectrum
reasonably well by adopting a cooler outer photospheric structure corresponding
to T_mod = 3250 K. The success of this model may indicate the observed
mid-infrared lines are formed in cool photospheric surface regions. Given the
uncertainties of the temperature structure and the likely presence of
inhomogeneities, we cannot rule out the possibility that our spectrum could be
mostly photospheric, albeit non-classical. Our data put new, strong constraints
on atmospheric models of Betelgeuse and we conclude that continued
investigation requires consideration of non-classical model photospheres as
well as possible effects of a MOLsphere. We show that the mid-infrared
water-vapor features have great diagnostic value for the environments of K and
M (super-) giant star atmospheres.Comment: Accepted by Ap
Stability and Hydrolyzation of Metal Organic Frameworks with Paddle-Wheel SBUs upon Hydration
Instability of most prototypical metal organic frameworks (MOFs) in the
presence of moisture is always a limita- tion for industrial scale development.
In this work, we examine the dissociation mechanism of microporous paddle wheel
frameworks M(bdc)(ted)0.5 [M=Cu, Zn, Ni, Co; bdc= 1,4-benzenedicarboxylate;
ted= triethylenediamine] in controlled humidity environments. Combined in-situ
IR spectroscopy, Raman, and Powder x-ray diffraction measurements show that the
stability and modification of isostructual M(bdc)(ted)0.5 compounds upon
exposure to water vapor critically depend on the central metal ion. A
hydrolysis reaction of water molecules with Cu-O-C is observed in the case of
Cu(bdc)(ted)0.5. Displacement reactions of ted linkers by water molecules are
identified with Zn(bdc)(ted)0.5 and Co(bdc)(ted)0.5. In contrast,.
Ni(bdc)(ted)0.5 is less suscept- ible to reaction with water vapors than the
other three compounds. In addition, the condensation of water vapors into the
framework is necessary to initiate the dissociation reaction. These findings,
supported by supported by first principles theoretical van der Waals density
functional (vdW-DF) calculations of overall reaction enthalpies, provide the
necessary information for de- termining operation conditions of this class of
MOFs with paddle wheel secondary building units and guidance for developing
more robust units
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