807 research outputs found

    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

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    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

    ΠΠΠ Π ΠΠ’Π˜Π’ΠΠΠ― ЭКОНОМИКА И ΠΠ•Π™Π ΠžΠ­ΠšΠžΠΠžΠœΠ˜ΠšΠ

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    This article is a reworked lecture I have given at theFinancialUniversityunder the Government of theRussian FederationinMoscow. This lecture has considered the epidemiology of narratives relevant to economic fluctuations (outcomes), allowing them to β€œgo viral” and spread far away, even worldwide, and thereby influencing economic outcomes. However, I had to accommodate my talk to the Russian audience adding some illustrative examples for better understanding. My basic goal in this paper is to describe what we know about narratives and the penchant of the human mind to be engaged by them, to consider reasons to expect that narratives might well be thought of as important, largely exogenous shocks to the aggregate economy. Thus, the main focus was on narratives going viral, affecting the economy in an age of neuroimaging, big data. This is because the human brain has always been highly tuned towards narratives, whether factual or not, to justify ongoing actions β€” even in such basic actions as spending and investing. Though these narratives are deeply human phenomena that are difficult to study in a scientific manner, quantitative analysis may help us gain a better understanding of these epidemics in the future. Many examples are seen as revealing the importance of the linkage of human brains and now computers through narratives associated with popular models of the economy and offering new research opportunities for both economics and neuroscience.Π­Ρ‚Π° ΡΡ‚Π°Ρ‚ΡŒΡ являСтся ΠΏΠ΅Ρ€Π΅Ρ€Π°Π±ΠΎΡ‚Π°Π½Π½ΠΎΠΉ Π»Π΅ΠΊΡ†ΠΈΠ΅ΠΉ, ΠΊΠΎΡ‚ΠΎΡ€ΡƒΡŽ я ΠΏΡ€ΠΎΡ‡ΠΈΡ‚Π°Π» Π² Ѐинансовом унивСрситСтС ΠΏΡ€ΠΈ ΠŸΡ€Π°Π²ΠΈΡ‚Π΅Π»ΡŒΡΡ‚Π²Π΅ Российской Π€Π΅Π΄Π΅Ρ€Π°Ρ†ΠΈΠΈ Π² МосквС. Π’ этой Π»Π΅ΠΊΡ†ΠΈΠΈ Π±Ρ‹Π»Π° рассмотрСна эпидСмиология Π½Π°Ρ€Ρ€Π°Ρ‚ΠΈΠ²ΠΎΠ², ΠΈΠΌΠ΅ΡŽΡ‰ΠΈΡ… ΠΎΡ‚Π½ΠΎΡˆΠ΅Π½ΠΈΠ΅ ΠΊ экономичСским колСбаниям (Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Π°ΠΌ), Ρ‡Ρ‚ΠΎ ΠΏΠΎΠ·Π²ΠΎΠ»ΠΈΠ»ΠΎ ΠΈΠΌ Β«ΡΡ‚Π°Ρ‚ΡŒ вирусными», Ρ€Π°ΡΠΏΡ€ΠΎΡΡ‚Ρ€Π°Π½ΠΈΡ‚ΡŒΡΡ Π΄Π°Π»Π΅ΠΊΠΎ, Π΄Π°ΠΆΠ΅ ΠΏΠΎ всСму ΠΌΠΈΡ€Ρƒ, ΠΈ Ρ‚Π΅ΠΌ самым ΠΏΠΎΠ²Π»ΠΈΡΡ‚ΡŒ Π½Π° экономичСскиС Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Ρ‹. Π’Π΅ΠΌ Π½Π΅ ΠΌΠ΅Π½Π΅Π΅ я Π΄ΠΎΠ»ΠΆΠ΅Π½ Π±Ρ‹Π» Π°Π΄Π°ΠΏΡ‚ΠΈΡ€ΠΎΠ²Π°Ρ‚ΡŒ ΠΌΠΎΠ΅ выступлСниС для российской Π°ΡƒΠ΄ΠΈΡ‚ΠΎΡ€ΠΈΠΈ, Π΄ΠΎΠ±Π°Π²ΠΈΠ² Π½Π΅ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ ΠΈΠ»Π»ΡŽΡΡ‚Ρ€Π°Ρ‚ΠΈΠ²Π½Ρ‹Π΅ ΠΏΡ€ΠΈΠΌΠ΅Ρ€Ρ‹ для Π»ΡƒΡ‡ΡˆΠ΅Π³ΠΎ понимания. Моя основная Ρ†Π΅Π»ΡŒ Π² этой ΡΡ‚Π°Ρ‚ΡŒΠ΅ состоит Π² Ρ‚ΠΎΠΌ, Ρ‡Ρ‚ΠΎΠ±Ρ‹ ΠΎΠΏΠΈΡΠ°Ρ‚ΡŒ Ρ‚ΠΎ, Ρ‡Ρ‚ΠΎ ΠΌΡ‹ Π·Π½Π°Π΅ΠΌ ΠΎ Π½Π°Ρ€Ρ€Π°Ρ‚ΠΈΠ²Π°Ρ… ΠΈ склонности чСловСчСского Ρ€Π°Π·ΡƒΠΌΠ° ΠΊ ΠΈΡ… Π²ΠΎΡΠΏΡ€ΠΈΡΡ‚ΠΈΡŽ, Π° Π·Π°Ρ‚Π΅ΠΌ ΠΎΠ±ΠΎΡΠ½ΠΎΠ²Π°Ρ‚ΡŒ ΠΏΡ€ΠΈΡ‡ΠΈΠ½Ρ‹ нашСго оТидания, Ρ‡Ρ‚ΠΎ Π½Π°Ρ€Ρ€Π°Ρ‚ΠΈΠ²Ρ‹ Π²ΠΏΠΎΠ»Π½Π΅ ΠΌΠΎΠ³ΡƒΡ‚ Ρ€Π°ΡΡΠΌΠ°Ρ‚Ρ€ΠΈΠ²Π°Ρ‚ΡŒΡΡ ΠΊΠ°ΠΊ Π²Π°ΠΆΠ½Ρ‹Π΅, Π² основном экзогСнныС потрясСния для экономики Π² Ρ†Π΅Π»ΠΎΠΌ. Π’Π°ΠΊΠΈΠΌ ΠΎΠ±Ρ€Π°Π·ΠΎΠΌ, основноС Π²Π½ΠΈΠΌΠ°Π½ΠΈΠ΅ Π±Ρ‹Π»ΠΎ ΡƒΠ΄Π΅Π»Π΅Π½ΠΎ Π½Π°Ρ€Ρ€Π°Ρ‚ΠΈΠ²Π°ΠΌ, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ становятся вирусными, Π²Π»ΠΈΡΡŽΡ‰ΠΈΠΌΠΈ Π½Π° экономику Π² эпоху Π½Π΅ΠΉΡ€ΠΎΠ²ΠΈΠ·ΡƒΠ°Π»ΠΈΠ·Π°Ρ†ΠΈΠΈ Π±ΠΎΠ»ΡŒΡˆΠΈΡ… Π΄Π°Π½Π½Ρ‹Ρ…. Π­Ρ‚ΠΎ ΠΏΠΎΡ‚ΠΎΠΌΡƒ, Ρ‡Ρ‚ΠΎ чСловСчСский ΠΌΠΎΠ·Π³ всСгда Π±Ρ‹Π» настроСн Π½Π° рассказы, Π±ΡƒΠ΄ΡŒ Ρ‚ΠΎ фактичСскиС ΠΈΠ»ΠΈ Π½Π΅Ρ‚, Ρ‡Ρ‚ΠΎΠ±Ρ‹ ΠΎΠΏΡ€Π°Π²Π΄Π°Ρ‚ΡŒ Ρ‚Π΅ΠΊΡƒΡ‰ΠΈΠ΅ дСйствия β€” Π΄Π°ΠΆΠ΅ Π² Ρ‚Π°ΠΊΠΈΡ… основных дСйствиях, ΠΊΠ°ΠΊ расходы ΠΈ инвСстиции. ΠŸΠΎΡΠΊΠΎΠ»ΡŒΠΊΡƒ эти рассказы ΡΠ²Π»ΡΡŽΡ‚ΡΡ Π³Π»ΡƒΠ±ΠΎΠΊΠΎ чСловСчСскими явлСниями, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ Ρ‚Ρ€ΡƒΠ΄Π½ΠΎ ΠΈΠ·ΡƒΡ‡ΠΈΡ‚ΡŒ Π½Π° Π½Π°ΡƒΡ‡Π½ΠΎΠΉ основС, количСствСнный Π°Π½Π°Π»ΠΈΠ· ΠΌΠΎΠΆΠ΅Ρ‚ ΠΏΠΎΠΌΠΎΡ‡ΡŒ Π½Π°ΠΌ Π² Π±ΡƒΠ΄ΡƒΡ‰Π΅ΠΌ Π»ΡƒΡ‡ΡˆΠ΅ ΠΏΠΎΠ½ΡΡ‚ΡŒ эти эпидСмии. МногиС ΠΏΡ€ΠΈΠΌΠ΅Ρ€Ρ‹ Ρ€Π°ΡΡΠΌΠ°Ρ‚Ρ€ΠΈΠ²Π°ΡŽΡ‚ΡΡ ΠΊΠ°ΠΊ Π²Π°ΠΆΠ½Ρ‹Π΅ Π΄ΠΎΠΊΠ°Π·Π°Ρ‚Π΅Π»ΡŒΡΡ‚Π²Π° связи чСловСчСского ΠΌΠΎΠ·Π³Π° ΠΈ Ρ‚Π΅ΠΏΠ΅Ρ€ΡŒ ΠΊΠΎΠΌΠΏΡŒΡŽΡ‚Π΅Ρ€ΠΎΠ² Ρ‡Π΅Ρ€Π΅Π· рассказы, связанныС с популярными модСлями экономики, Ρ‡Ρ‚ΠΎ ΠΈ прСдставляСт Π½ΠΎΠ²Ρ‹Π΅ возмоТности для исслСдований Π² области ΠΊΠ°ΠΊ экономики, Ρ‚Π°ΠΊ ΠΈ Π½Π΅ΠΉΡ€ΠΎΠ½Π°ΡƒΠΊΠΈ.

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

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    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

    Have Financial Markets Become More Informative?

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    The finance industry has grown. Financial markets have become more liquid. Information technology has improved. But have prices become more informative? Using stock and bond prices to forecast earnings, we find that the information content of market prices has not increased since 1960. The magnitude of earnings surprises, however, has increased. A baseline model predicts that as the efficiency of information production increases, prices become more disperse and covary more strongly with future earnings. The forecastable component of earnings improves capital allocation and serves as a direct measure of welfare. We find that this measure has remained stable. A model with endogenous information acquisition predicts that an increase in fundamental uncertainty also increases informativeness as the incentive to produce information grows. We find that uncertainty has indeed increased outside of the S&P 500, but price informativeness has not

    Stock market volatility and business cycle: Evidence from linear and nonlinear causality tests

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    This paper investigates the relationship between stock market volatility and the business cycle in four major economies, namely the US, Canada, Japan and the UK. We employ both linear and nonlinear bivariate causality tests and we further conduct a multivariate analysis to explore possible spillover effects across countries. Our results suggest that there is a bidirectional causal relationship between stock market volatility and the business cycle within each country and additionally reveal that the recent financial crisis plays an important role in this context. Finally, we identify a significant impact of the US on the remaining markets

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

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    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

    Predicting the Spread of Financial Innovations: An Epidemiological Approach

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    I construct an estimable statistic that predicts whether a financial innovation will spread. The approach embeds the multi-host SIR model from epidemiology within a financial model of correlated securities trade; and takes advantage of the related predictive tools from mathematical epidemiology, including the basic reproductive ratio (R0) and herd immunity. In the model, banks and their creditors are assumed to have imperfect information about a newly-created security, and must search over the portfolios of other investors and intermediaries to infer the security's properties. In the absence of historical returns data, a large mass of firms holding the new security and not experiencing insolvency provides a positive signal about the distribution of its returns within the current period, and perpetuates further holding of the security. The model yields a set of structural equations that are used to construct the statistic. I provide two estimation strategies for the statistic; and identify 12 theoretical parameter restrictions that enable inference when only a subset of the model's parameters are identifiable. I use the approach to predict the spread of exchange traded funds (ETFs) and asset-backed securities (ABS). Additionally, I show how regulators can use the method to monitor the joint solvency of depository institutions within a given geographic region

    UK imports, third country effect and the global financial crisis: Evidence from the asymmetric ARDL method

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    This paper examines the role of exchange rate volatility in determining real imports. As a robustness check, it further explores the impact of the recent global financial crisis which is a period characterized by heightened exchange rate volatility. More specifically, we investigate the impact of exchange rate volatility on UK real imports from Germany, Japan and the US during the period January 1991–March 2013. In contrast to most studies which focus on bilateral trade, we additionally explore the third country exchange rate volatility effect on UK imports. To capture the nonlinear features which often characterize macroeconomic data, we employ the asymmetric autoregressive distributed lag (ARDL) approach to cointegration. Our results suggest that exchange rate volatility plays an important role and reveal that there is a significant effect of the recent financial crisis on UK imports. This finding is consistent when we test for the third country volatility effect. Finally, we find that there is a significant causal relationship between exchange rate volatility and UK imports both in bilateral tests and in tests which account for the third country exchange rate volatility

    Volatility in the Housing Market: Evidence on Risk and Return in the London Sub-market

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    The impact of volatility in housing market analysis is reconsidered via examination of the risk-return relationship in the London housing market is examined. In addition to providing the first empirical results for the relationship between risk (as measured by volatility) and returns for this submarket, the analysis offers a more general message to empiricists via a detailed and explicit evaluation of the impact of empirical design decisions upon inferences. In particular, the negative risk-return relationship discussed frequently in the housing market literature is examined and shown to depend upon typically overlooked decisions concerning components of the empirical framework from which statistical inferences are drawn
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