Studies related to primitive chemistry. A proton and nitrogen-14 nuclear magnetic resonance amino acid and nucleic acid constituents and a and their possible relation to prebiotic

Preliminary proton nuclear magnetic resonance (NMR) studies were made to determine the applicability of this technique for the study of interactions between monomeric and polymeric amino acids with monomeric nucleic acid bases and nucleotides. Proton NMR results for aqueous solutions (D2O) demonstrated interactions between the bases cytosine and adenine and acidic and aromatic amino acids. Solutions of 5'-AMP admixed with amino acids exhibited more complex behavior but stacking between aromatic rings and destacking at high amino acids concentration was evident. The multisite nature of 5'-AMP was pointed out. Chemical shift changes for adenine and 5'-AMP with three water soluble polypeptides demonstrated that significant interactions exist. It was found that the linewidth-pH profile of each amino acid is unique. It is concluded that NMR techniques can give significant and quantitative data on the association of amino acid and nucleic acid constituents

Testing for rational speculative bubbles in the Brazilian residential real-estate market

Speculative bubbles have been occurring periodically in local or global real estate markets and are considered a potential cause of economic crises. In this context, the detection of explosive behaviors in the financial market and the implementation of early warning diagnosis tests are of critical importance. The recent increase in Brazilian housing prices has risen concerns that the Brazilian economy may have a speculative housing bubble. In the present paper, we employ a recently proposed recursive unit root test in order to identify possible speculative bubbles in data from the Brazilian residential real-estate market. The empirical results show evidence for speculative price bubbles both in Rio de Janeiro and Sao Paulo, the two main Brazilian cities

House price Keynesianism and the contradictions of the modern investor subject

This article conceptualises the marked downturn in UK house prices in the 2007-2009 period in relation to longer-term processes of national economic restructuring centred on a new model of homeownership. The structure of UK house prices has been impacted markedly by the Labour Government‟s efforts to ingrain a particular notion of financial literacy amid the move towards an increasingly asset-based system of welfare. New model welfare recipients and new model homeowners have thereby been co-constituted in a manner consistent with a new UK growth regime of „house price Keynesianism‟. However, the investor subjects who drive such growth are necessarily rendered uncertain as compared with the idealised image of Government policy because of their reliance on the credit-creating decisions of private financial institutions. The recent steep decline in UK house prices is explained here as an epiphenomenon of the disruptive effect on the idealised image caused by the dependence of investor subjects on pricing dynamics not of their making

Theory of Fano-Kondo effect of transport properties through quantum dots

The Fano-Kondo effect in zero-bias conductance is investigated based on a theoretical model for the T-shaped quantum dot. The conductance as a function of the gate voltage is generally characterized by a Fano asymmetric parameter q. With varying temperature the conductance shows a crossover between the high and low temperature regions compared with the Kondo temperature T_K: two Fano asymmetric peaks at high temperatures and the Fano-Kondo plateau inside a Fano peak at low temperatures. Temperature dependence of conductance is calculated numerically by the Finite temperature density matrix renormalization group method (FT-DMRG).Comment: 8 pages, 7 figure

Introduction to Eurocrisis, Neoliberalism and the Common

This introduction frames the articles collected in the special section as the outcome of a process of ‘self-education’ taking place in the Italian free university network UniNomade 2.0 between 2010 and 2013. The open seminars and conferences orga- nized by UniNomade 2.0 took as their object of inquiry the concept of the Common, while the articles selected focus in particular on the sovereign debt crisis of the European Union (Eurocrisis) following the global financial crisis of 2008. The intro- duction thus summarizes the overall approach of contemporary ‘post-operaist’ authors such as Toni Negri, Christian Marazzi, Maurizio Lazzarato, Andrea Fumagalli and Stefano Lucarelli, and Carlo Vercellone to the new role of financial capital, the transformation of money, the material constitution of Europe, the role played by the relationship between debtors and creditors, and the possibilities opened by the concept of Commonfare for struggles against austerity

Investigations of Aerobic Methane Oxidation in Two Marine Seep Environments: Part 1—Chemical Kinetics

Microbial aerobic oxidation is known to be a significant sink of marine methane (CH4), contributing to the relatively minor atmospheric release of this greenhouse gas over vast stretches of the ocean. However, the chemical kinetics of aerobic CH4 oxidation are not well established, making it difficult to predict and assess the extent that CH4 is oxidized in seawater following seafloor release. Here we investigate the kinetics of aerobic CH4 oxidation using mesocosm incubations of fresh seawater samples collected from seep fields in Hudson Canyon, U.S. Atlantic Margin and MC118, Gulf of Mexico to gain a fundamental chemical understanding of this CH4 sink. The goals of this investigation were to determine the response or lag time following CH4 release until more rapid oxidation begins, the reaction order, and the stoichiometry of reactants utilized (i.e., CH4, oxygen, nitrate, phosphate, trace metals) during CH4 oxidation. The results for both Hudson Canyon and MC118 environments show that CH4 oxidation rates sharply increased within less than one month following the CH4 inoculation of seawater. However, the exact temporal characteristics of this more rapid CH4 oxidation varied based on location, possibly dependent on the local circulation and biogeochemical conditions at the point of seawater collection. The data further suggest that methane oxidation behaves as a first‐order kinetic process and that the reaction rate constant remains constant once rapid CH4 oxidation begins

Investigations of Aerobic Methane Oxidation in Two Marine Seep Environments: Part 2—Isotopic Kinetics

During aerobic oxidation of methane (CH4) in seawater, a process which mitigates atmospheric emissions, the 12C‐isotopologue reacts with a slightly greater rate constant than the 13C‐isotopologue, leaving the residual CH4 isotopically fractionated. Prior studies have attempted to exploit this systematic isotopic fractionation from methane oxidation to quantify the extent that a CH4 pool has been oxidized in seawater. However, cultivation‐based studies have suggested that isotopic fractionation fundamentally changes as a microbial population blooms in response to an influx of reactive substrates. Using a systematic mesocosm incubation study with recently collected seawater, here we investigate the fundamental isotopic kinetics of aerobic CH4 oxidation during a microbial bloom. As detailed in a companion paper, seawater samples were collected from seep fields in Hudson Canyon, U.S. Atlantic Margin, and atop Woolsey Mound (also known as Sleeping Dragon) which is part of lease block MC118 in the northern Gulf of Mexico, and used in these investigations. The results from both Hudson Canyon and MC118 show that in these natural environments isotopic fraction for CH4 oxidation follows a first‐order kinetic process. The results also show that the isotopic fractionation factor remains constant during this methanotrophic bloom once rapid CH4 oxidation begins and that the magnitude of the fractionation factor appears correlated with the first‐order reaction rate constant. These findings greatly simplify the use of natural stable isotope changes in CH4 to assess the extent that CH4 is oxidized in seawater following seafloor release

Coastal Ocean and Shelf-Sea Biogeochemical Cycling of Trace Elements and Isotopes: Lessons Learned from GEOTRACES

Continental shelves and shelf seas play a central role in the global carbon cycle. However, their importance with respect to trace element and isotope (TEI) inputs to ocean basins is less well understood. Here, we present major findings on shelf TEI biogeochemistry from the GEOTRACES programme as well as a proof of concept for a new method to estimate shelf TEI fluxes. The case studies focus on advances in our understanding of TEI cycling in the Arctic, transformations within a major river estuary (Amazon), shelf sediment micronutrient fluxes and basin-scale estimates of submarine groundwater discharge. The proposed shelf flux tracer is 228-radium (T1/2 = 5.75 yr), which is continuously supplied to the shelf from coastal aquifers, sediment porewater exchange and rivers. Model-derived shelf 228Ra fluxes are combined with TEI/ 228Ra ratios to quantify ocean TEI fluxes from the western North Atlantic margin. The results from this new approach agree well with previous estimates for shelf Co, Fe, Mn and Zn inputs and exceed published estimates of atmospheric deposition by factors of approximately 3-23. Lastly, recommendations are made for additional GEOTRACES process studies and coastal margin-focused section cruises that will help refine the model and provide better insight on the mechanisms driving shelf-derived TEI fluxes to the ocean.This article is part of the themed issue \u27Biological and climatic impacts of ocean trace element chemistry\u27

Value at Risk models with long memory features and their economic performance

We study alternative dynamics for Value at Risk (VaR) that incorporate a slow moving component and information on recent aggregate returns in established quantile (auto) regression models. These models are compared on their economic performance, and also on metrics of first-order importance such as violation ratios. By better economic performance, we mean that changes in the VaR forecasts should have a lower variance to reduce transaction costs and should lead to lower exceedance sizes without raising the average level of the VaR. We find that, in combination with a targeted estimation strategy, our proposed models lead to improved performance in both statistical and economic terms

Constituting monetary conservatives via the 'savings habit': New Labour and the British housing market bubble

The ongoing world credit crunch might well kill off the most recent bubble dynamics in the British housing market by driving prices systematically downwards from their 2007 peak. Nonetheless, the experience of that bubble still warrants analytical attention. The Labour Government might not have been responsible for consciously creating it, but it has certainly grasped the opportunities the bubble has provided in an attempt to enforce a process of agential change at the heart of the British economy. The key issue in this respect is the way in which the Government has challenged the legitimacy of passive welfare receipts in favour of establishing a welfare system based on incorporating the individual into an active asset-holding society. The housing market has taken on new political significance as a means for individuals first to acquire assets and then to accumulate wealth on the back of asset ownership. The ensuing integration of the housing market into an increasingly reconfigured welfare system has permeated into the politics of everyday life. It has been consistent with individuals remaking their political subjectivities in line with preferences for the type of conservative monetary policies that typically keep house price bubbles inflated