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Perfecting the union ::national and state authority in the US Constitution /
No full textIn 'Perfecting the Union', Max M. Edling focuses on the reform of the American Union brought about by the framing and adoption of the Constitution and the resulting division of duties and powers between the national government and the states. He argues that the Constitution profoundly altered the structure of the American Union and made the federal government more effective than under the defunct Articles of Confederation, but does not accept that federal power expanded at the expense of the states
A Hercules in the Cradle:War, Money, and the American State, 1783-1867
No full textTwo and a half centuries after the American Revolution the United States stands as one of the greatest powers on earth and the undoubted leader of the western hemisphere. This stupendous evolution was far from a foregone conclusion at independence. The conquest of the North American continent required violence, suffering, and bloodshed. It also required the creation of a national government strong enough to go to war against, and acquire territory from, its North American rivals.In A Hercules in the Cradle, Max M. Edling argues that the federal government’s abilities to tax and to borrow money, developed in the early years of the republic, were critical to the young nation’s ability to wage war and expand its territory. He traces the growth of this capacity from the time of the founding to the aftermath of the Civil War, including the funding of the War of 1812 and the Mexican War. Edling maintains that the Founding Fathers clearly understood the connection between public finance and power: a well-managed public debt was a key part of every modern state. Creating a debt would always be a delicate and contentious matter in the American context, however, and statesmen of all persuasions tried to pay down the national debt in times of peace. A Hercules in the Cradle explores the origin and evolution of American public finance and shows how the nation’s rise to great-power status in the nineteenth century rested on its ability to go into debt
A revolution in favor of government origins of the U.S. Constitution and the making of the American state
No full textIn this new interpretation of America's origins, Max Edling argues the the Federalists were primarily concerned with building a government that could act vigorously in defense of American interests. The Constitution transferred the powers of war making and resource extraction from the states to the national government thereby creating a nation-state invested with all the important powers of Europe's eighteenth-century "fiscal-military states." A strong centralized government, however, challenged the American people's deeply ingrained distrust of unduly concentrated authority. To secure the Constitution's adoption the Federalists had to accommodate the formation of a powerful national government to the strong current of anti-statism in the American political tradition. They did so by designing a government that would be powerful in times of crisis, but which would make only limited demands on the citizenry and have a sharply restricted presence in society. The Constitution promised the American people the benefit of government without its costs
The subzero microbiome: Microbial activity in frozen and thawing soils
No full textMost of the Earth's biosphere is characterized by low temperatures (<5 °C) and cold-adapted microorganisms are widespread. These psychrophiles have evolved a complex range of adaptations of all cellular constituents to counteract the potentially deleterious effects of low kinetic energy environments and the freezing of water. Microbial life continues into the subzero temperature range, and this activity contributes to carbon and nitrogen flux in and out of ecosystems, ultimately affecting global processes. Microbial responses to climate warming and in particular, thawing of frozen soils are not yet well understood although the threat of microbial contribution to positive feedback of carbon flux is substantial. To date, several studies have examined microbial community dynamics in frozen soils and permafrost due to changing environmental conditions, and some have undertaken the complicated task of characterizing microbial functional groups and how their activity changes with changing conditions, either in situ or by isolating and characterizing macromolecules. With increasing temperature and wetter conditions microbial activity of key microbes and subsequent efflux of greenhouse gases also increase. In this review, we aim to provide an overview of microbial activity in seasonally frozen soils and permafrost. With a more detailed understanding of the microbiological activities in these vulnerable soil ecosystems, we can begin to predict and model future expectations for carbon release and climate change.Peer reviewe
A Transfer Report on the Development of a Framework to Evaluate Search Interfaces for their Support of Different User Types and Search Tactics
No full textAs the understanding of search systems, user needs and seeking strategies is developing, the design of search user interfaces is evolving to support more complicated and exploratory forms of search. With the design of new search features that enable these richer modes of exploration, comes the need to better understand the support they provide. In this report a new evaluation framework is presented that analyses search features for how they a) contribute to an overall interface, b) allow users to carry out different search tactics, and c) support different types of users and their needs. The novel contributions of the framework improve on some of the limitations of typical user studies, and allow search systems to be systematically analysed in much more detail and in much less time. The presented evaluation framework is then validated in three ways. First the validity of the models used as the building blocks of the framework are investigated through related work. Second the method of integrating these building-block models is validated and strengthened by consensus of expert opinion. Third, the overall approach is validated by comparing its analyses to the results of previously carried out user studies. The validation process has shown both the value of the framework and identified areas of future work that should be addressed for the framework to be completed. This report concludes with the set of contributions that the framework makes, and why the remaining work will be challenging, but critical to the final design
Transcriptomic and proteomic response of the organohalide respiring bacterium Desulfoluna spongiiphila to growth with 2,6-dibromophenol as electron acceptor
No full textPeer reviewe
Reductive dehalogenation activity of indigenous microorganism in sediments of the Hackensack River, New Jersey
No full textOrganohalogen pollutants are of concern in many river and estuarine environments, such as the New York-New Jersey Harbor estuary and its tributaries. The Hackensack River is contaminated with various metals, hydrocarbons and halogenated organics, including polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins. In order to examine the potential for microbial reductive dechlorination by indigenous microorganisms, sediment samples were collected from five different estuarine locations along the Hackensack River. Hexachlorobenzene (HCB), hexabromobenzene (HBB), and pentachloroaniline (PCA) were selected as model organohalogen pollutants to assess anaerobic dehalogenating potential. Dechlorinating activity of HCB and PCA was observed in sediment microcosms for all sampling sites. HCB was dechlorinated via pentachlorobenzene (PeCB) and trichlorobenzene (TriCB) to dichlorobenzene (DCB). PCA was dechlorinated via tetrachloroaniline (TeCA), trichloroanilines (TriCA), and dichloroanilines (DCA) to monochloroaniline (MCA). No HBB debromination was observed over 12 months of incubation. However, with HCB as a co-substrate slow HBB debromination was observed with production of tetrabromobenzene (TeBB) and tribromobenzene (TriBB). Chloroflexi specific 16S rRNA gene PCR-DGGE followed by sequence analysis detected Dehalococcoides species in sediments of the freshwater location, but not in the estuarine site. Analysis targeting 12 putative reductive dehalogenase (rdh) genes showed that these were enriched concomitant with HCB or PCA dechlorination in freshwater sediment microcosms
Impact of Estuarine Gradients on Reductive Dechlorination of 1,2,3,4-Tetrachlorodibenzo-p-dioxin in River Sediment Enrichment Cultures
No full textPolychlorinated dibenzo-p-dioxins (PCDDs) are among the most persistent organic pollutants. Although the total input of PCDDs into the environment has decreased substantially over the past four decades, their input via non-point sources is still increasing, especially in estuarine metropolitan areas. Here we report on the microbially mediated reductive dechlorination of PCDDs in anaerobic enrichment cultures established from sediments collected from five locations along the Hackensack River, NJ and investigate the impacts of sediment physicochemical characteristics on dechlorination activity. Dechlorination of 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-TeCDD) and abundance of Dehalococcoides spp. negatively correlated with salinity and sulfate concentration in sediments used to establish the cultures. 1,2,3,4-TeCDD was dechlorinated to a lesser extent in cultures established from sediments from the tidally influenced estuarine mouth of the river. In cultures established from low salinity sediments, 1,2,3,4-TeCDD was reductively dechlorinated with the accumulation of 2-monochlorodibenzo-p-dioxin as the major product. Sulfate concentrations above 2 mM inhibited 1,2,3,4-TecDD dechlorination activity. Consecutive lateral- and peri- dechlorination took place in enrichment cultures with a minimal accumulation of 2,3-dichlorodibenzo-p-dioxin in active cultures. A Dehalococcoides spp. community was enriched and accounted for up to 64% of Chloroflexi detected in these sediment cultures.Peer reviewe
Reconstructed genomes of novel Dehalococcoides mccartyi strains from 1,2,3,4-tetrachlorodibenzo-p-dioxin-dechlorinating enrichment cultures reveal divergent reductive dehalogenase gene profiles
No full textPolychlorinated dibenzo-p-dioxin (PCDD) contaminated sites are widespread and associated with a variety of anthropogenic sources. PCDDs and other organohalide pollutants can serve as terminal electron acceptors for anaerobic respiration by specialized bacteria containing reductive dehalogenases (RdhA). These microorganisms, therefore, play an important role in bioremediation of PCDD contaminated sites. Two anaerobic enrichment cultures established using sediments collected from the PCDD polluted Hackensack (USA) and Kymijoki (Finland) rivers showed robust reductive dechlorination of 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-TeCDD). Here, we report on the draft genome reconstructions of the two predominant Dehalococcoides strains from the metagenomes of these dehalogenating enrichment cultures. Furthermore, we gathered a complete list of reductive dehalogenases in the two predominant Dehalococcoides strains, and determined which are likely to be responsible for reductive dechlorination of PCDDs. The divergent rdhA gene profiles of the Dehalococcoides strains likely reflect their exposure to different organohalide compounds in their original habitats. Both draft genomes contained a full length rdhA gene with high sequence similarity to a reductive dehalogenase gene found in Dehalococcoides mccartyi CBDB1 known to reductively dechlorinate 1,2,3,4-tetrachlorobenzene, i.e. cbrA. This gene homologue might also be responsible for reductive dechlorination of 1,2,3,4-TeCDD in the enrichments and could be used as a biomarker to determine the potential for bioremediation of PCDD contaminated sediments.Peer reviewe
Evaluation of carbon isotope fractionation during anaerobic reductive dehalogenation of chlorinated and brominated benzenes
No full textCompound specific stable isotope analysis (CSIA) has been established as a useful tool to evaluate in situ biodegradation. Here, CSIA was used to determine microbial dehalogenation of chloro- and bromobenzenes in microcosms derived from Hackensack River sediments. Gas chromatography-isotope ratio mass spectrometry (GC-IRMS) was used to measure carbon isotope fractionation during reductive dehalogenation of hexachlorobenzene (HCB), pentachlorobenzene (PeCB), 1,2,3,5-tetrachlorobenzene (TeCB), 1,2,3,5-tetrabromobenzene (TeBB), and 1,3,5-tribromobenzene (TriBB). Strong evidence of isotope fractionation coupled to dehalogenation was not observed in the substrate, possibly due to the low solubilities of the highly halogenated benzene substrates and a dilution of the isotope signal. Nonetheless, we could measure a depletion of the δ13C value in the dichlorobenzene product during dechlorination of HCB, the sequential depletion and enrichment of δ13C value for trichlorobenzene in TeCB dechlorinating cultures, and the enrichment of δ13C during debromination of TriBB. This indicates that a measurable isotope fractionation occurred during reductive dehalogenation of highly halogenated chloro- and bromobenzenes in aquatic sediments. Thus, although more quantitative measurements will be needed, the data suggests that CSIA may have application for monitoring in situ microbial reductive dehalogenation of highly halogenated benzenes.Peer reviewe
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