Predictions of short-term rates and the expectations hypothesis of the term structure of interest rates

Despite its important role in monetary policy and finance, the expectations hypothesis (EH) of the term structure of interest rates has received virtually no empirical support. The empirical failure of the EH was attributed to a variety of econometric biases associated with the single-equation models used to test it; however, none account for it. This paper analyzes the EH by focusing on its fundamental tenet - the predictability of the short-term rate. This is done by comparing h-month ahead forecasts for the 1- and 3-month Treasury yields implied by the EH with the forecasts from random-walk, Diebold and Lei (2006), and Duffee (2002) models. The evidence suggests that the failure of the EH is likely a consequence of market participants’ inability to predict the short-term rate. JEL Classification: E40, E52expectations theory, random walk, time-varying risk premium

Predictions of short-term rates and the expectations hypothesis

Despite its role in monetary policy and finance, the expectations hypothesis (EH) of the term structure of interest rates has received virtually no empirical support. The empirical failure of the EH was attributed to a variety of econometric biases associated with the single-equation models most often used to test it, although no bias seems to account for the extent and magnitude of the failure. This paper analyzes the EH by focusing on the predictability of the short-term rate. This is done by comparing h-month ahead forecasts for the 1- and 3-month Treasury bill yields implied by the EH with the forecasts from random-walk, Diebold and Li’s (2006), and Duffee’s (2002) models. The evidence suggests that the failure of the EH is likely a consequence of market participants’ inability to adequately predict the short-term rate, in that none of these models out-performs a simple random walk model in recursive, real time experiments. Using standard methods that take into account the additional uncertainty caused by the need to estimate model parameters, the null hypothesis of equal predictive accuracy of each models relative to the random walk alternative is never rejected.Rational expectations (Economic theory) ; Interest rates

Pfas environmental pollution and antioxidant responses: An overview of the impact on human field

Due to their unique properties, perfluorinated substances (PFAS) are widely used in multiple industrial and commercial applications, but they are toxic for animals, humans included. This review presents some available data on the PFAS environmental distribution in the world, and in particular in Europe and in the Veneto region of Italy, where it has become a serious problem for human health. The consumption of contaminated food and drinking water is considered one of the major source of exposure for humans. Worldwide epidemiological studies report the negative effects that PFAS have on human health, due to environmental pollution, including infertility, steroid hormone perturbation, thyroid, liver and kidney disorders, and metabolic disfunctions. In vitro and in vivo researches correlated PFAS exposure to oxidative stress effects (in mammals as well as in other vertebrates of human interest), produced by a PFAS-induced increase of reactive oxygen species formation. The cellular antioxidant defense system is activated by PFAS, but it is only partially able to avoid the oxidative damage to biomolecules

Thermodynamic and Kinetic Stabilities of Al(III) Complexes with N2O3 Pentadentate Ligands

: Al(III) complexes have been recently investigated for their potential use in imaging with positron emission tomography (PET) by formation of ternary complexes with the radioisotope fluorine-18 (18F). Although the derivatives of 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) are the most applied chelators for [Al18F]2+ labelling and (pre)clinical PET imaging, non-macrocyclic, semi-rigid pentadentate chelators having two N- and three O-donor atoms such as RESCA1 and AMPDA-HB have been proposed with the aim to allow room temperature labelling of temperature-sensitive biomolecules. The paucity of stability data on Al(III) complexes used for PET imaging instigated a complete thermodynamic and kinetic solution study on Al(III) complexes with aminomethylpiperidine (AMP) derivatives AMPTA and AMPDA-HB and the comparison with a RESCA1-like chelator CD3A-Bn (trans-1,2-diaminocyclohexane-N-benzyl-N,N',N'-triacetic acid). The stability constant of [Al(AMPDA-HB)] is about four orders of magnitude higher than that of [Al(AMPTA)] and [Al(CD3A-Bn)], highlighting the greater affinity of phenolates with respect to acetate O-donors. On the other hand, the kinetic inertness of the complexes, determined by following the Cu2+-mediated transmetallation reactions in the 7.5-10.5 pH range, resulted in a spontaneous and hydroxide-assisted dissociation slightly faster for [Al(AMPTA)] than for the other two complexes (t1/2 = 4.5 h for [Al(AMPTA)], 12.4 h for [Al(AMPDA-HB)], and 24.1 h for [Al(CD3A-Bn)] at pH 7.4 and 25 °C). Finally, the [AlF]2+ ternary complexes were prepared and their stability in reconstituted human serum was determined by 19F NMR experiments

Bioinformatics and mathematical modelling in the study of receptor-receptor interactions and receptor oligomerization: focus on adenosine receptors.

none8sìThe concept of intra-membrane receptor-receptor interactions (RRIs) between different types of G protein-coupled receptors (GPCRs) and evidence for their existence was introduced by Agnati and Fuxe in 1980/81 through the biochemical analysis of the effects of neuropeptides on the binding characteristics of monoamine receptors in membrane preparations from discrete brain regions and functional studies of the interactions between neuropeptides and monoamines in the control of specific functions such as motor control and arterial blood pressure control in animal models. Whether GPCRs can form high-order structures is still a topic of an intense debate. Increasing evidence, however, suggests that the hypothesis of the existence of high-order receptor oligomers is correct. A fundamental consequence of the view describing GPCRs as interacting structures, with the likely formation at the plasma membrane of receptor aggregates of multiple receptors (Receptor Mosaics) is that it is no longer possible to describe signal transduction simply as the result of the binding of the chemical signal to its receptor, but rather as the result of a filtering/integration of chemical signals by the Receptor Mosaics (RMs) and membrane-associated proteins. Thus, in parallel with experimental research, significant efforts were spent in bioinformatics and mathematical modelling. We review here the main approaches that have been used to assess the interaction interfaces allowing the assembly of GPCRs and to shed some light on the integrative functions emerging from the complex behaviour of these RMs. Particular attention was paid to the RMs generated by adenosine A(2A), dopamine D-2, cannabinoid CB1, and metabotropic glutamate mGlu(5) receptors (A(2A). D-2, CB1, and mGlu(5), respectively), and a possible approach to model the interplay between the D-2-A(2A)-CB1 and D-2-A(2A)-mGlu(5) trimers is proposed. This article is part of a Special Issue entitled: "Adenosine Receptors". (C) 2010 Elsevier B.V. All rights reserved.openD. GUIDOLIN; F. CIRUELA; S. GENEDANI; M. GUESCINI; C. TORTORELLA; G. ALBERTIN; K. FUXE; L.F. AGNATID., Guidolin; F., Ciruela; S., Genedani; Guescini, Michele; C., Tortorella; G., Albertin; K., Fuxe; L. F., Agnat

C2C12 MYOBLASTS RELEASE MICRO-VESICLES CONTAINING mtDNA AND PROTEINS INVOLVED IN SIGNAL TRANSDUCTION

none11Micro-vesicles can be released by different cell types and operate as ‘safe containers’ mediatine inter-cellular communication. In this work we investigated whether cultured myoblasts could release exosomes. The reported data demonstrate, for the first time, that C2C12 myoblasts release micro-vesicles as shown by the presence of two exosome markers (Tsg101 and Alix proteins). Using real-time PCR analysis it was shown that these micro-vesicles, like other cell types, carry mtDNA. Proteomic characterization of the released micro-vesicle contents showed the presence of many proteins involved in signal transduction. The bioinformatics assessment of the Disorder Index and Aggregation Index of these proteins suggested that C2C12 micro-vesicles mainly deliver the machinery for signal transduction to target cells rather than key proteins involved in hub functions in molecular networks. The presence of IGFBP-5 in the purified micro-vesicles represents an exception, since this binding protein can play a key role in the modulation of the IGF-1 signalling pathway. In conclusion, the present findings demonstrate that skeletal muscle cells release micro-vesicles, which probably have an important role in the communication processes within skeletal muscles and between skeletal muscles and other organs. In particular, the present findings suggest possibile new diagnostic approaches to skeletal muscle diseases.openM. GUESCINI; D. GUIDOLIN; L. VALLORANI; L. CASADEI; A.M. GIOACCHINI; P. TIBOLLO; M. BATTISTELLI; E. FALCIERI; L. BATTISTIN; L.F. AGNATI; V. STOCCHIGuescini, Michele; D., Guidolin; Vallorani, Luciana; Casadei, Lucia; Gioacchini, ANNA MARIA; P., Tibollo; Battistelli, Michela; Falcieri, Elisabetta; L., Battistin; L. F., Agnati; Stocchi, Vilbert