The interconnectedness of the economic content in the speeches of the US Presidents

The speeches stated by influential politicians can have a decisive impact on the future of a country. In particular, the economic content of such speeches affects the economy of countries and their financial markets. For this reason, we examine a novel dataset containing the economic content of 951 speeches stated by 45 US Presidents from George Washington (April 1789) to Donald Trump (February 2017). In doing so, we use an economic glossary carried out by means of text mining techniques. The goal of our study is to examine the structure of significant interconnections within a network obtained from the economic content of presidential speeches. In such a network, nodes are represented by talks and links by values of cosine similarity, the latter computed using the occurrences of the economic terms in the speeches. The resulting network displays a peculiar structure made up of a core (i.e. a set of highly central and densely connected nodes) and a periphery (i.e. a set of non-central and sparsely connected nodes). The presence of different economic dictionaries employed by the Presidents characterize the core-periphery structure. The Presidents’ talks belonging to the network’s core share the usage of generic (non-technical) economic locutions like “interest” or “trade”.While the use of more technical and less frequent terms characterizes the periphery (e.g. “yield”). Furthermore, the speeches close in time share a common economic dictionary. These results together with the economics glossary usages during the US periods of boom and crisis provide unique insights on the economic content relationships among Presidents’ speeches. This is a post-peer-review, pre-copyedit version of an article published in Annals of Operations Research. The final authenticated version is available online at: http://dx.doi.org/10.1007/s10479-019-03372-

A joint text mining-rank size investigation of the rhetoric structures of the US Presidents’ speeches

© 2019 Elsevier Ltd This work presents a text mining context and its use for a deep analysis of the messages delivered by politicians. Specifically, we deal with an expert systems-based exploration of the rhetoric dynamics of a large collection of US Presidents’ speeches, ranging from Washington to Trump. In particular, speeches are viewed as complex expert systems whose structures can be effectively analyzed through rank-size laws. The methodological contribution of the paper is twofold. First, we develop a text mining-based procedure for the construction of the dataset by using a web scraping routine on the Miller Center website – the repository site collecting the speeches. Second, we explore the implicit structure of the discourse data by implementing a rank-size procedure over the individual speeches, being the words of each speech ranked in terms of their frequencies. The scientific significance of the proposed combination of text-mining and rank-size approaches can be found in its flexibility and generality, which let it be reproducible to a wide set of expert systems and text mining contexts. The usefulness of the proposed method and of the speeches analysis is demonstrated by the findings themselves. Indeed, in terms of impact, it is worth noting that interesting conclusions of social, political and linguistic nature on how 45 United States Presidents, from April 30, 1789 till February 28, 2017 delivered political messages can be carried out. Indeed, the proposed analysis shows some remarkable regularities, not only inside a given speech, but also among different speeches. Moreover, under a purely methodological perspective, the presented contribution suggests possible ways of generating a linguistic decision-making algorithm

Design of an X-band constant impedance LINAC for compact light project

Within the framework of Horizon 2020 project, Compact Light, in order to provide a high performance, high-gradient X-band technology, for the new generation of hard X-ray FEL, a travelling wave (TW) Linac, working on 2pi/3 mode at 11.9952 GHz, fed by two types of asymmetrically couplers, has been designed. The design was performed using CST Microwave Studio frequency domain solver. First, simulations have been conduct in order to obtain the best trade-off between single cell’s parameters, varying iris aperture. Then, the both couplers, with and without pumping port, has been tuned to avoid reflections at the input port. Finally, the entire structure, with 5 cells, was simulated. The main structure parameters will be present and we will also show and discuss the acceleranting gradient obtained vary with linac lenght and input power

Optical and electrical behavior of synthetic melanin thin films spray-coated

AbstractWe investigated the optical and the electrical conductivity properties of synthetic melanin thin films spray-coated on glass. These films showed a broadband monotonic increase of the absorption coefficient, decreasing the wavelength in the Visible-NIR range. Conductivity as a function of the temperature evidenced a semiconductor like character and a hysteretic behaviour after thermal annealing up to 475 K. Thermal activation energies extrapolated by resistance curves have been explained by using the framework of a band-model as for an amorphous semiconductor

Electrical transport properties of microcrystalline silicon grown by PECVD

The dark conductivity and Hall mobility of hydrogenated silicon films deposited varying the silane concentration f=SiH4/(SiH4+H2) in a conventional plasma enhanced chemical vapor deposition system have been investigated as a function of temperature, taking into account their structural properties. The electrical properties have been studied in terms of a structural two-phase model. A clear transition from the electrical transport governed by a crystalline phase, in the range 1%3%, has been evidenced. Some metastable effects of the dark conductivity have been noticed

Progress on the π-mode X-band RF cavity for SPARC

The Frascati photo-injector SPARC (Pulsed Self Amplified Coherent Radiation Source) will be equipped with a X-band RF cavity for linearizing emittance to enhance bunch compression and for reducing bunch longitudinal energy spread. The nine cells standingwave cavity prototype made of separated cells has been already built and measured. In this paper we report on characterisation of the first brazed prototype. Heat load studies have been performed as well to design the cooling system for the final device

Electromagnetic and beam dynamics studies for high gradient accelerators at terahertz frequencies

THz radiation is one of the most appealing portion of the electromagnetic spectrum in terms of multi-disciplinary use in basic science and technology. Beyond the numerous applications, a great interest is its potential for future, compact linear accelerators. Conventional radio-frequency accelerating structures operating at the S and C band can reach gradients up to 30 - 50MV/m, respectively; higher accelerating gradients, of the order of 100MV/m, have been obtained with X-band cavities. THz-based accelerating structures enable operation at even higher gradient, potentially up to the GV/m scale, holding great potential for their application to free-electron lasers and linear colliders, for instance. Here we present electromagnetic and beam dynamics studies about the use of a dielectric loaded waveguide to accelerate electron bunches by mean of a narrow-band multi-cycle THz pulse. The excitation of the accelerating structure by the THz pulse and the bunch acceleration in the excited field are investigated through CST Microwave Studio and GPT simulations

Proteomic changes and molecular effects associated with Cr(III) and Cr(VI) treatments on germinating kiwifruit pollen

The present study is aimed at identifying molecular changes elicited by Cr(III) and Cr(VI) on germinating kiwifruit pollen. To address this question, comparative proteomic and DNA laddering analyses were performed. While no genotoxic effect was detected, a number of proteins whose accumulation levels were altered by treatments were identified. In particular, the upregulation of some proteins involved in the scavenging response, cell redox homeostasis and lipid synthesis could be interpreted as an oxidative stress response induced by Cr treatment. The strong reduction of two proteins involved in mitochondrial oxidative phosphorylation and a decline in ATP levels were also observed. The decrease of pollen energy availability could be one of the causes of the severe inhibition of the pollen germination observed upon exposure to both Cr(III) and Cr(VI). Finally, proteomic and biochemical data indicate proteasome impairment: the consequential accumulation of misfolded/damaged proteins could be an important molecular mechanism of Cr(III) toxicity in pollen