1,230 research outputs found

    Heart rate variability analysis for the identification of the preictal interval in patients with drug-resistant epilepsy

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    Electrocardiogram (ECG) recordings, lasting hours before epileptic seizures, have been studied in the search for evidence of the existence of a preictal interval that follows a normal ECG trace and precedes the seizure's clinical manifestation. The preictal interval has not yet been clinically parametrized. Furthermore, the duration of this interval varies for seizures both among patients and from the same patient. In this study, we performed a heart rate variability (HRV) analysis to investigate the discriminative power of the features of HRV in the identification of the preictal interval. HRV information extracted from the linear time and frequency domains as well as from nonlinear dynamics were analysed. We inspected data from 238 temporal lobe seizures recorded from 41 patients with drug-resistant epilepsy from the EPILEPSIAE database. Unsupervised methods were applied to the HRV feature dataset, thus leading to a new perspective in preictal interval characterization. Distinguishable preictal behaviour was exhibited by 41% of the seizures and 90% of the patients. Half of the preictal intervals were identified in the 40 min before seizure onset. The results demonstrate the potential of applying clustering methods to HRV features to deepen the current understanding of the preictal state.FCT: CISUC -UID/CEC/00326/2020/ SFRH/BD/147862/2019info:eu-repo/semantics/publishedVersio

    Chemoselective oxidation of benzophenazines by m-CPBA: n-oxidation vs. oxidative cleavage

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    Chemoselectivity is observed when a pyran-benzo[a]phenazine and a furan-benzo[a]phenazine from beta-lapachone and nor-beta-lapachone, respectively, were submitted to oxidation by m-CPBA. The pyran phenazine furnished mainly macrolactones, while the furan one led exclusively to a phenazine N-8 oxide. To understand this difference in reactivity, we synthesized a new furan phenazine, with the reactive double bond site less hindered than that of the derivative from nor-beta-lapachone. This furan phenazine, upon oxidation with m-CPBA, furnished mainly the expected macrolactone. These experimental results, along with preliminary analysis based on mechanical molecular calculations of the ground state of the substrates, allowed us to suggest that the observed chemoselectivity has a steric oxidant approach control origin, related to the presence of the geminal methyl groups in the phenazine structure. Several of the synthesized compounds are, herein, reported for the first time

    Persons with moderate Alzheimer's disease improve activities and mood via instruction technology.

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    Background: Three studies assessed the (a) effectiveness of verbal instructions presented via technology in helping persons with moderate Alzheimer's disease perform daily activities and (b) impact of activity engagement on mood. Methods: The 3 studies targeted coffee preparation with 2 women, use of make-up with 2 women, and use of make-up and tea preparation with 3 women. Intervention effects on activity performance were assessed through nonconcurrent multiple baseline designs across participants or multiple baseline designs across activities. The impact of activity on mood was assessed by recording indices of happiness during activity trials and parallel nonactivity periods. Results: Verbal instructions presented via technology were effective in helping all participants perform the target activities. The participants also showed mood improvement (ie, increases in indices of happiness) during the activity. Conclusion: These results suggest that the approach reported may be a useful strategy for helping persons with Alzheimer's disease

    PULEX: Influence of environment radiation background on biochemistry and biology of cultured cells and on their response to genotoxic agents

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    Some years ago we performed two experiments aimed at studying the influence of the background radiation on living matter by exploiting the low radiation background environment in the underground Gran Sasso Laboratory of the INFN. Their results were consistent with the hypothesis that the “normal” background radiation determines an adaptive response, although they cannot be considered conclusive. PULEX-3 (the third experiment of the series) is aimed at comparing the effects of different background radiation environments on metabolism of cultured mammalian cells, with substantial improvements with respect to the preceding ones. The experiment was designed to minimize variabilities, by maintaining two cultures of Chinese hamster V79 cells in exponential growth for up to ten months in the underground Gran Sasso Laboratory (LNGS), while two other cultures were maintained in parallel in a biological laboratory installed at the LNGS outside the tunnel. Exposure due to γ-rays was reduced by a factor of about 10 in the underground laboratory while the Rn concentration was small in both cases. After ten months the cells grown in the underground laboratory, compared to those grown in the external one, exhibited: i) a significantly lower capacity to scavenge reactive oxygen species (ROS), and ii) an increased sensitivity to the mutagenic effect of rays. Since the probability that this finding is due to casual induction of radiosensitive mutants is extremely low, it corroborates the hypothesis that cells grown in a “normal” background radiation environment exhibit an adaptive response when challenged with genotoxic agents, which is lost after many generations in a low background radiation environment

    Analysis of tourism in Campania as a tool for the development of high-quality cultural services for sightseers: The “Reale Osservatorio Vesuviano” case history

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    The purpose of this work is to identify the guidelines for the development and diversification of the cultural touristic offer achievable at the Reale Osservatorio Vesuviano (ROV). Founded in 1841, it is the oldest volcano observatory in the world and it has always had the vocation for scientific-naturalistic and formative tourism. The present study investigates the connections between the sociology of tourism and the ROV’s sustainability and competitiveness as a tourist destination. Here it is performed a study of the tourist flow, based on the sociology of tourism and on the correct processing of data sets, distinguishing the ''statistical information on tourism" from "tourism statistics", as such a study is the basis of a proper market strategy in different sectors. Tourism remains, in fact, an important phenomenon in world economy: despite the economic crisis of recent years, international tourist arrivals show a positive development of the trend in all the major sub-areas into which the large international areas are traditionally divided. The principles for a future marketing plan were outlined after collecting all the relevant information. The plan was designed to enhance the overall touristic offer of the ROV, never ceasing to consider the integration of natural- scientific aspects and cultural events to be offered within the observatory itself.Published64-872TM. Divulgazione Scientifica6TM. Poli Museali1VV. AltroN/A or not JC

    Formyl Peptide Receptor as a Novel Therapeutic Target for Anxiety-Related Disorders

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    Formyl peptide receptors (FPR) belong to a family of sensors of the immune system that detect microbe-associated molecules and inform various cellular and sensorial mechanisms to the presence of pathogens in the host. Here we demonstrate that Fpr2/3-deficient mice show a distinct profile of behaviour characterised by reduced anxiety in the marble burying and light-dark box paradigms, increased exploratory behaviour in an open-field, together with superior performance on a novel object recognition test. Pharmacological blockade with a formyl peptide receptor antagonist, Boc2, in wild type mice reproduced most of the behavioural changes observed in the Fpr2/3(-/-) mice, including a significant improvement in novel object discrimination and reduced anxiety in a light/dark shuttle test. These effects were associated with reduced FPR signalling in the gut as shown by the significant reduction in the levels of p-p38. Collectively, these findings suggest that homeostatic FPR signalling exerts a modulatory effect on anxiety-like behaviours. These findings thus suggest that therapies targeting FPRs may be a novel approach to ameliorate behavioural abnormalities present in neuropsychiatric disorders at the cognitive-emotional interface

    Calibration of the Logarithmic-Periodic Dipole Antenna (LPDA) Radio Stations at the Pierre Auger Observatory using an Octocopter

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    An in-situ calibration of a logarithmic periodic dipole antenna with a frequency coverage of 30 MHz to 80 MHz is performed. Such antennas are part of a radio station system used for detection of cosmic ray induced air showers at the Engineering Radio Array of the Pierre Auger Observatory, the so-called Auger Engineering Radio Array (AERA). The directional and frequency characteristics of the broadband antenna are investigated using a remotely piloted aircraft (RPA) carrying a small transmitting antenna. The antenna sensitivity is described by the vector effective length relating the measured voltage with the electric-field components perpendicular to the incoming signal direction. The horizontal and meridional components are determined with an overall uncertainty of 7.4^{+0.9}_{-0.3} % and 10.3^{+2.8}_{-1.7} % respectively. The measurement is used to correct a simulated response of the frequency and directional response of the antenna. In addition, the influence of the ground conductivity and permittivity on the antenna response is simulated. Both have a negligible influence given the ground conditions measured at the detector site. The overall uncertainties of the vector effective length components result in an uncertainty of 8.8^{+2.1}_{-1.3} % in the square root of the energy fluence for incoming signal directions with zenith angles smaller than 60{\deg}.Comment: Published version. Updated online abstract only. Manuscript is unchanged with respect to v2. 39 pages, 15 figures, 2 table

    Multi-resolution anisotropy studies of ultrahigh-energy cosmic rays detected at the Pierre Auger Observatory

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    We report a multi-resolution search for anisotropies in the arrival directions of cosmic rays detected at the Pierre Auger Observatory with local zenith angles up to 80∘80^\circ and energies in excess of 4 EeV (4×10184 \times 10^{18} eV). This search is conducted by measuring the angular power spectrum and performing a needlet wavelet analysis in two independent energy ranges. Both analyses are complementary since the angular power spectrum achieves a better performance in identifying large-scale patterns while the needlet wavelet analysis, considering the parameters used in this work, presents a higher efficiency in detecting smaller-scale anisotropies, potentially providing directional information on any observed anisotropies. No deviation from isotropy is observed on any angular scale in the energy range between 4 and 8 EeV. Above 8 EeV, an indication for a dipole moment is captured; while no other deviation from isotropy is observed for moments beyond the dipole one. The corresponding pp-values obtained after accounting for searches blindly performed at several angular scales, are 1.3×10−51.3 \times 10^{-5} in the case of the angular power spectrum, and 2.5×10−32.5 \times 10^{-3} in the case of the needlet analysis. While these results are consistent with previous reports making use of the same data set, they provide extensions of the previous works through the thorough scans of the angular scales.Comment: Published version. Added journal reference and DOI. Added Report Numbe

    Ultrahigh-energy neutrino follow-up of Gravitational Wave events GW150914 and GW151226 with the Pierre Auger Observatory

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    On September 14, 2015 the Advanced LIGO detectors observed their first gravitational-wave (GW) transient GW150914. This was followed by a second GW event observed on December 26, 2015. Both events were inferred to have arisen from the merger of black holes in binary systems. Such a system may emit neutrinos if there are magnetic fields and disk debris remaining from the formation of the two black holes. With the surface detector array of the Pierre Auger Observatory we can search for neutrinos with energy above 100 PeV from point-like sources across the sky with equatorial declination from about -65 deg. to +60 deg., and in particular from a fraction of the 90% confidence-level (CL) inferred positions in the sky of GW150914 and GW151226. A targeted search for highly-inclined extensive air showers, produced either by interactions of downward-going neutrinos of all flavors in the atmosphere or by the decays of tau leptons originating from tau-neutrino interactions in the Earth's crust (Earth-skimming neutrinos), yielded no candidates in the Auger data collected within ±500\pm 500 s around or 1 day after the coordinated universal time (UTC) of GW150914 and GW151226, as well as in the same search periods relative to the UTC time of the GW candidate event LVT151012. From the non-observation we constrain the amount of energy radiated in ultrahigh-energy neutrinos from such remarkable events.Comment: Published version. Added journal reference and DOI. Added Report Numbe
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