432 research outputs found

    Reasoning of non- and pre-linguistic creatures: How much do the experiments tell us?

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    If a conclusion was reached that creatures without a language capability exhibit some form of a capability for logic, this would shed a new light on the relationship between logic, language, and thought. Recent experimental attempts to test whether some animals, as well as pre-linguistic human infants, are capable of exclusionary reasoning are taken to support exactly that conclusion. The paper discusses the analyses and conclusions of two such studies: Call's (2004) two cups task, and Mody and Carey's (2016) four cups task. My paper exposes hidden assumptions within these analyses, which enable the authors to settle on the explanation which assigns logical capabilities to the participants of the studies, as opposed to the explanations which do not. The paper then demonstrates that the competing explanations of the experimental results are theoretically underdeveloped, rendering them unclear in their predictions concerning the behavior of cognitive subjects, and thus difficult to distinguish by use of experiments. Additionally, it is questioned whether the explanations are rivals at all, i.e. whether they compete to explain the cognitive processes of the same level. The contribution of the paper is conceptual. Its aim is to clear up the concepts involved in these analyses, in order to avoid oversimplified or premature conclusions about the cognitive abilities of pre- and non-linguistic creatures. It is also meant to show that the theoretical space surrounding the issues involved might be much more diverse and unknown than many of these studies imply

    Diagnostics of plasma in the ionospheric D-region: detection and study of different ionospheric disturbance types

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    Here we discuss our recent investigations of the ionospheric plasma by using very low and low frequency (VLF/LF) radio waves. We give a review of how to detect different low ionospheric reactions (sudden ionospheric disturbances) to various terrestrial and extra-terrestrial events, show their classification according to intensity and time duration, and present some methods for their detections in time and frequency domains. Investigations of detection in time domain are carried out for intensive long-lasting perturbations induced by solar X-ray flares and for short-lasting perturbations caused by gamma ray bursts. We also analyze time variations of signals used in the low ionospheric monitoring after earthquake events. In addition, we describe a procedure for the detection of acoustic and gravity waves from the VLF/LF signal analysis in frequency domain. The research of the low ionospheric plasma is based on data collected by the VLF/LF receivers located in Belgrade, Serbia

    Possible role of a hydrogen peroxide-mediated mechanism in glucocorticoid receptor functional alterations associated with moderate asthma

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    It is well known that pathogenesis and maintenance of chronic asthma is associated with alterations of glucocorticoid receptor (GR) function, and also with persistent pulmonary inflammation, the important mediators of which are reactive oxygen and nitrogen species. In this paper, we tested a hypothesis that GR functional alterations in asthma result from the action of oxidants. To that end, we conducted a series of ex vivo treatments of peripheral blood mononuclear cells (PBMCs) of healthy donors with oxidizing agents (3 morpholinosydnonimine, SIN1; S-nitroso-N-acetyl-penicillamine, SNAP; and hydrogen peroxide, H2O2) and compared the resulting GR modifications with those previously noticed in asthmatic patients. The results show that treatment of PBMCs by H2O2 provoked an increase in the level of GR protein, accompanied by a rise in the number of hormone-binding sites and a decline in the receptor's affinity for the hormone. The H2O2 induced changes, including a characteristic GR isoprotein expression pattern, were found to be very similar to the GR changes previously observed in PBMCs of moderate asthmatic patients, but not in mild asthmatics and healthy subjects. Treatment with the other oxidants applied herein produced different effects or exerted no influence on GR. Thus, this study provides preliminary data suggesting that functional alterations of the GR associated with moderate asthma may be mediated by redox mechanisms that are based on oxidative and regulatory actions of H2O2

    Laser sheet scattering and the cameras' positions in particle image velocimetry

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    Simulations of laser sheet scattering by microparticles, based on the generalized Lorenz-Mie theory for the case of numerous random spatial distributions of scattering particles, were done, using the novel computational time saving strategy. This type of scattering by particles immersed in a fluid flow and its recording on cameras, presents the essence of particle image velocimetry systems. The continuous and large change of the intensity of a scattered light failing on the camera causes the sequences of images of varying quality, which makes many of them useless. This paper shows how the problem could be alleviated by determining the angles of low relative standard deviation of scattered light intensity and using them for recording, as well as by avoiding the angles of high relative standard deviation of scattered light intensity

    Music between philosophy and science: the applicability of scientific results to the philosophy of music

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    Disertacija se bavi odnosom između dva pristupa istraživanju muzike: empirijskog pristupa eksperimentalne psihologije i kognitivne neuronauke, i spekulativnog pristupa filozofske estetike muzike. Cilj disertacije je određivanje odnosa među problemima, teorijskim okvirima i domenima istraživanja ova dva pristupa. Disertacija daje odgovor na pitanje da li se filozofski i empirijski pristup bave istim, ili barem povezivim aspektima muzike. Disertacija bi trebalo i da odgovori da li se rezultati empirijskog istraživanja muzike mogu primeniti u filozofskoj estetici muzike. Disertacija je podeljena u tri poglavlja. Svako poglavlje se bavi jednim problemom u filozofiji muzike: značenjem u muzici, vrednošću muzike, i odnosom muzike i emocija. Za svaki pojedinačni filozofski problem prikazan u disertaciji, pokazuje se da eksperimentalni rezultati donose zanimljive i relevantne uvide za filozofiju muzike. Zaključak disertacije je da analiza eksperimentalnih studija može doneti filozofima značajne uvide, ne samo po pitanju konkretnih estetičkih teorija, nego i u metodološkom razmatranju, s obzirom na to da se u tezi višestruko pokazuje da interdisciplinarno istraživanje koje je sprovedeno u samoj disertaciji otkriva metode od velike koristi za filozofe, a koji su nepristupačni uobičajenom spekulativnom filozofskom istraživanjuThe dissertation discusses the relationship between two approaches to researching music: the empirical approach of experimental psychology and cognitive neuroscience, and the speculative approach of philosophical aesthetics of music. The aim of the dissertation is to determine the relationship between problems, conceptual frameworks, and domains of inquiry of the two approaches. The dissertation should answer whether the philosophical and the empirical approach deal with the same, or at least relatable aspects of music. In particular, it should answer whether the results of the empirical research contribute to the debates of philosophical aesthetics of music. Each of the three chapters of the dissertation deals with one particular problem in philosophy of music: meaning in music, value of music, and the relationship between music and the emotions. For each particular philosophical problem discussed in these chapters, it is demonstrated that the experimental results provide interesting insights for philosophy of music. It is concluded in the dissertation that philosophers can benefit from examining experimental studies, not only regarding the particular aesthetic theories, but also in regard to the methodological consideration, since the dissertation shows that this kind of interdisciplinary approach uncovers methods useful to philosophers, not commonly available to the armchair philosophical approac

    Modification of the structural and optical properties of commercial ZnO powder by mechanical activation

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    Mechanical activation was used as a method for modification of the structural and optical properties of commercial ZnO powder. For this purpose zinc oxide powder was mechanically treated by grinding in a high-energy vibro-mill in a continual regime in air up to 300 minutes. Starting and modified ZnO samples were characterized using XRD, BET and TEM measurements. Optical properties of these samples were investigated by Raman and photoluminescence (PL) spectroscopy. The color of commercial ZnO powder was white while mechanically activated ZnO powder was dark yellow, indicating the presence of nonstoichiometry. In the Raman spectra of non-activated sample Raman modes of bulk ZnO were observed, while the spectra of modified samples point out structural and stoichiometric changes. The PL spectra of modified samples excited by 325 and 442 nm lines of a He-Cd laser show great difference with respect to the spectra of the original sample. This study confirms that change in the defect structure of the ZnO crystal lattice introduced by mechanical activation affects the optical properties of this material

    VOLCANISM OF HOT SPOTS ON THE RÉUNION AS THE EXAMPLE

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    Réunion (French: La Réunion, formerly: Īle Bourbon) is beside the Mauritius the largest and the youngest island on the Mascarene Plateau in the Indian Ocean. The island is of volcanic origin, formed through volcanic activity initiated by deeply settled “hot spot” inside the Earth’s mantle. It was formed within the last 2 million years from lava effusions whose volume is up to now nearly 75,000 km3. Only 3% of its volume is emergent and the total height from the sea floor is 6,500 m. The island is about 40 km in width with about 800,000 inhabitants. The capital city is St Denis. The nature of the island is impressive: active volcano, mountains above 3,000 m in height and deep canyon, frequently exceeding 2,000 m in depth. Since 2010, about 40% of its area is announced a National park and a UNESCO World Heritage site

    Laser doppler velocimetry and confined flows

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    Finding the mode, in which two component laser Doppler velocimetry can be applied to flows confined in cylindrical tubes or vessels, was the aim of this study. We have identified principle issues that influence the propagation of laser beams in laser Doppler velocimetry system, applied to flow confined in cylindrical tube. Among them, the most important are influences of fluid and wall refractive indices, wall thickness and internal radius ratio and beam intersection angle. In analysis of the degrees of these influences, we have applied mathematical model, based on geometrical optics. The separation of measurement volumes, that measure different velocity components, has been recognized as the main drawback. To overcome this, we propose a lens with dual focal length primary focal length for the measurement of one velocity component and secondary focal length for the measurement of the other velocity component. We present here the procedure for calculating the optimal value of secondary focal length, depending on experimental set-up parameters. The mathematical simulation of the application of the dual focal length lens, for chosen cases presented here, confirmed the accuracy of the proposed procedure

    Electrical properties of mechanically activated zinc oxide

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    Microstructural properties of a commercial zinc oxide powder were modified by mechanical activation in a high-energy vibro-mill. The obtained powders were dry pressed and sintered at 1100°C for 2 h. The electrical properties of grain boundaries of obtained ZnO ceramics were studied using an ac impedance analyzer. For that purpose, the ac electrical response was measured in the temperature range from 23 to 240°C in order to determine the resistance and capacitance of grain boundaries. The activation energies of conduction were obtained using an Arrhenius equation. Donor densities were calculated from Mott-Schottky measurements. The influence of microstructure, types and concentrations of defects on electrical properties was discussed
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