0000000000529893

AUTHOR

Andrea Santangelo

0000-0003-4187-9560

Temporal Analysis of EXO 0531−66 in Outburst

We report a timing analysis of the Be transient X-ray binary EXO 053109-6609.2 in outburst observed with BeppoSAX. The luminosity of the source is ~1.1 × 1037 ergs s-1, similar to that observed in the previous three outbursts. The source shows pulsations from 0.1 up to 60 keV. The pulsed fraction does not seem to decrease with the energy. The pulse profile is double peaked in the whole energy band. The barycentric pulse period is 13.67590 ± 0.00008 s at MJD 50,520.0. The average rate of period change during the ~2 days of BeppoSAX observation is (3.7 ± 0.5) × 10-9 s s-1. Comparison with ROSAT data allowed the determination of a secular spin-down sec ~(3.67 ± 0.05) × 10−11 s s-1, computed ov…

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BeppoSAX observation of 4U 1907+09: Detection of a cyclotron line and its second harmonic

Abstract We report the detection of a cyclotron absorption line and its second harmonic in the average spectrum of the high mass X-ray binary 4U1907+09 observed by the BeppoSAX satellite. The broad band spectral capability of BeppoSAX allowed a good determination of the continuum against which the two absorption features are evident at ∼ 19 and ∼ 39 keV. Correcting for the gravitational redshift of a ∼ 1.4 M⊙ neutron star, the inferred surface magnetic field strength is Bsurf = 2.1 × 1012 G.

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Multivariate approaches to behavioral physiology

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Effects of Substantia Nigra pars compacta lesion on the behavioral sequencing in the 6-OHDA model of Parkinson’s disease

The basal ganglia circuitry plays a crucial role in the sequential organization of behavior. Here we studied the behavioral structure of the animals after 21 days of 6-OHDA-induced lesion of the dopaminergic nigrostriatal system. Frequencies and durations of individual components of the behavioral repertoire were calculated; moreover, whether a temporal organization of the activity was present, it was investigated by using T-pattern analysis, a multivariate approach able to detect the real-time sequential organization of behavior. Six sham-depleted and six rats with unilateral 6−OHDA-lesion of the Substantia Nigra pars compacta were used. As to quantitative evaluations, the comparison betwe…

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A 0535+26 in the August/September 2005 outburst observed by RXTE and INTEGRAL

In this Letter we present results from INTEGRAL and RXTE observations of the spectral and timing behavior of the High Mass X-ray Binary A 0535+26 during its August/September 2005 normal (type I) outburst with an average flux F(5-100keV)~400mCrab. The search for cyclotron resonance scattering features (fundamental and harmonic) is one major focus of the paper. Our analysis is based on data from INTEGRAL and RXTE Target of Opportunity Observations performed during the outburst. The pulse period is determined. X-ray pulse profiles in different energy ranges are analyzed. The broad band INTEGRAL and RXTE pulse phase averaged X-ray spectra are studied. The evolution of the fundamental cyclotron …

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Recurring sequences of multimodal non-verbal and verbal communication during a human psycho-social stress test: A temporal pattern analysis

Abstract Background The Trier Social Stress Test (TSST) is a widely used protocol to study human psycho-social stress responses. Quantitative reports of non-verbal behaviors have been carried out by means of the Ethological Coding System for Interviews (ECSI). However, no data have described whether and how non-verbal and verbal behaviors take part in the composition of multimodal sequences of communication during the test. Method Five non-verbal ECSI categories and four verbal behaviors related with communication were included in the Ethogram. A focal sampling was employed to ensure a high temporal resolution of the behavioral annotation. T-Pattern Analysis was employed to detect statistic…

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A relativistically smeared spectrum in the neutron star X-ray binary 4U 1705−44: looking at the inner accretion disc with X-ray spectroscopy

Iron emission lines at 6.4-6.97 keV, identified with fluorescent Kalpha transitions, are among the strongest discrete features in the X-ray band. These are therefore one of the most powerful probes to infer the properties of the plasma in the innermost part of the accretion disc around a compact object. In this paper we present a recent XMM observation of the X-ray burster 4U 1705-44, where we clearly detect a relativistically smeared iron line at about 6.7 keV, testifying with high statistical significance that the line profile is distorted by high velocity motion in the accretion disc. As expected from disc reflection models, we also find a significant absorption edge at about 8.3 keV; th…

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Temporal structure of the rat's behavior in elevated plus maze test

Aim of the research was to evaluate, by means of quantitative and multivariate temporal pattern analyses, the behavior of Wistar rat in elevated plus maze (EPM) test. On the basis of an ethogram encompassing 24 behavioral elements, quantitative results showed that 130.14 ± 8.01 behavioral elements occurred in central platform and in closed arms (protected zones), whereas 88.62 ± 6.04 occurred in open arms (unprotected zones). Percent distribution was characterized by a prevalence of sniffing, walking and vertical exploration. Analysis of minute-by-minute duration evidenced a decrease for time spent in open arms and central platform and an increase for time spent in closed arms. As to multiv…

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BeppoSAX observation of the transient X-ray pulsar GS 1843+009

Abstract The transient X-ray pulsar GS 1843+009 was observed by BeppoSAX satellite on 1997 April 4, while it was at flux level of 50 mCrab in the 20–200 keV energy band. Using the MECS and LECS concentrators, the source position was measured with unprecedented accuracy of 30. In this poster we present results on both spectral and temporal analysis.

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Significant divergences between the temporal structure of the behavior in Wistar and in the spontaneously more anxious DA/Han strain of rats tested in elevated plus maze

Abstract The aim of present research is to study the temporal structure of the behavior in two strains of rats with different basal level of emotionality. To this purpose, the temporal profile of the behavior in Wistar rat and in the spontaneously more anxious DA/Han strain was analyzed in the Elevated Plus Maze. Both quantitative and multivariate t-pattern analyses were carried out. In comparison with Wistar, DA/Han subjects showed a significant reduction of the permanence in open arm and a significant increase of the time spent in the central platform of the maze. Mean frequencies of each behavioral element showed significant modifications both in open and in closed arm. Multivariate t-pa…

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A broadband spectral analysis of 4U 1702-429 using XMM-Newton and BeppoSAX data

Most of the X-ray binary systems containing neutron stars classified as Atoll sources show two different spectral states, called soft and hard. Moreover, a large number of these systems show a reflection component relativistically smeared in their spectra, which gives information on the innermost region of the system. Our aim is to investigate the poorly studied broadband spectrum of the low mass X-ray binary system 4U 1702-429, which was recently analysed combining XMM-Newton and INTEGRAL data. The peculiar value of the reflection fraction brought us to analyse further broadband spectra of 4U 1702-429. We re-analysed the spectrum of the XMM-Newton/INTEGRAL observation of 4U 1702-429 in the…

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Brain histamine depletion enhances the behavioural sequences complexity of mice tested in the open-field: Partial reversal effect of the dopamine D2/D3 antagonist sulpiride.

Markers of histaminergic dysregulation were found in several neuropsychiatric disorders characterized by repetitive behaviours, thoughts and stereotypies. We analysed the effect of acute histamine depletion by means of i. c.v. injections of alpha-fluoromethylhistidine, a blocker of histidine decarboxylase, on the temporal organization of motor sequences of CD1 mice behaviour in the open-field test. An ethogram encompassing 9 behavioural components was employed. Durations and frequencies were only slightly affected by treatments. However, as revealed by multivariate t-pattern analysis, histamine depletion was associated with a striking increase in the number of behavioural patterns. We found…

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The Large Area Detector onboard the eXTP mission

The Large Area Detector (LAD) is the high-throughput, spectral-timing instrument onboard the eXTP mission, a flagship mission of the Chinese Academy of Sciences and the China National Space Administration, with a large European participation coordinated by Italy and Spain. The eXTP mission is currently performing its phase B study, with a target launch at the end-2027. The eXTP scientific payload includes four instruments (SFA, PFA, LAD and WFM) offering unprecedented simultaneous wide-band X-ray timing and polarimetry sensitivity. The LAD instrument is based on the design originally proposed for the LOFT mission. It envisages a deployed 3.2 m2 effective area in the 2-30 keV energy range, a…

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Temporal patterns of rat behaviour in the central platform of the elevated plus maze. Comparative analysis between male subjects of strains with different basal levels of emotionality

We have analyzed the temporal patterns of behaviour of male rats of the Wistar and DA/Han strains on the central platform of the elevated plus maze. The ethogram encompassed 10 behavioural elements. Durations, frequencies and latencies showed quantitative differences as to walking and sniffing activities. Wistar rats displayed significantly lower latency and significantly higher durations and frequencies of walking activities. DA/Han rats showed a significant increase of sniffing duration. In addition, DA/Han rats showed a significantly higher amount of time spent in the central platform. Multivariate T-pattern analysis revealed differences in the temporal organization of behaviour of the t…

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The Wide Field Imager of the International X-ray Observatory

The International X-ray Observatory (IXO) will be a joint X-ray observatory mission by ESA, NASA and JAXA. It will have a large effective area (3 m 2 at 1.25 keV) grazing incidence mirror system with good angular resolution (5 arcsec at 0.1–10 keV) and will feature a comprehensive suite of scientific instruments: an X-ray Microcalorimeter Spectrometer, a High Time Resolution Spectrometer, an X-ray Polarimeter, an X-ray Grating Spectrometer, a Hard X-ray Imager and a Wide-Field Imager. The Wide Field Imager (WFI) has a field-of-view of 18 ft � 18 ft. It will be sensitive between 0.1 and 15 keV, offer the full angular resolution of the mirrors and good energy resolution. The WFI will be imple…

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GrailQuest and HERMES: hunting for gravitational wave electromagnetic counterparts and probing space-time quantum foam

GrailQuest (Gamma-ray Astronomy International Laboratory for Quantum Exploration of Space-Time) is an ambitious astrophysical mission concept that uses a fleet of small satellites whose main objective is to search for a dispersion law for light propagation in vacuo. Within Quantum Gravity theories, different models for space-time quantization predict relative discrepancies of the speed of photons w.r.t. the speed of light that depend on the ratio of the photon energy to the Planck energy. This ratio is as small as 10-23 for photons in the γ- ray band (100 keV). Therefore, to detect this effect, light must propagate over enormous distances and the experiment must have extraordinary sensitivi…

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GrailQuest: hunting for atoms of space and time hidden in the wrinkle of Space-Time: A swarm of nano/micro/small-satellites to probe the ultimate structure of Space-Time and to provide an all-sky monitor to study high-energy astrophysics phenomena

AbstractGrailQuest(Gamma Ray Astronomy International Laboratory for QUantum Exploration of Space-Time) is a mission concept based on a constellation (hundreds/thousands) of nano/micro/small-satellites in low (or near) Earth orbits. Each satellite hosts a non-collimated array of scintillator crystals coupled with Silicon Drift Detectors with broad energy band coverage (keV-MeV range) and excellent temporal resolution (≤ 100 nanoseconds) each with effective area$\sim 100 \text {cm}^{2}$∼100cm2. This simple and robust design allows for mass-production of the satellites of the fleet. This revolutionary approach implies a huge reduction of costs, flexibility in the segmented launching strategy, …

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Brain histamine and behavioral neuroscience

ABSTRACT NON PREVISTO DALLA PUBBLICAZIONE

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Hard X-ray emission from neutron star X-ray binaries

Abstract In this paper we review our current knowledge of the hard X–ray emission properties of accreting X–ray Binary Pulsars and old accreting neutron stars in Low Mass X–ray Binaries in light of 7 years of BeppoSAX and RXTE observations. The paper is divided in two parts. In the first part we review the more recent findings on the phase-dependent broad band continua and cyclotron resonance scattering features observed in many systems of the X-ray Binary Pulsar class. In the second part we review the hard X-ray emission of LMXRB focussing on the hard X-ray components extending up to energies of a few hundred keV that have been clearly detected in sources of both the atoll and Z classes. T…

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The HERMES-Technologic and Scientific Pathfinder

HERMES-TP/SP (High Energy Rapid Modular Ensemble of Satellites Technologic and Scientific Pathfinder) is a constellation of six 3U nano-satellites hosting simple but innovative X-ray detectors, characterized by a large energy band and excellent temporal resolution, and thus optimized for the monitoring of Cosmic High Energy transients such as Gamma Ray Bursts and the electromagnetic counterparts of Gravitational Wave Events, and for the determination of their positions. The projects are funded by the Italian Ministry of University and Research and by the Italian Space Agency, and by the European Union Horizon 2020 Research and Innovation Program under Grant Agreement No. 821896. HERMES-TP/S…

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Testing reflection features in 4U 1705-44 with XMM-Newton, BeppoSAX, and RXTE in the hard and soft states

We use data of the bright atoll source 4U 1705-44 taken with XMM-Newton, BeppoSAX and RXTE both in the hard and in the soft state to perform a self-consistent study of the reflection component in this source. Although the data from these X-ray observatories are not simultaneous, the spectral decomposition is shown to be consistent among the different observations, when the source flux is similar. We therefore select observations performed at similar flux levels in the hard and soft state in order to study the spectral shape in these two states in a broad band (0.1-200 keV) energy range, with good energy resolution, and using self-consistent reflection models. These reflection models provide…

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T-pattern detection and analysis for the discovery of hidden features of behaviour

Abstract Background The behaviour of all living beings consists of hidden patterns in time; consequently, its nature and its underlying dynamics are intrinsically difficult to be perceived and detected by the unaided observer. Method Such a scientific challenge calls for improved means of detection, data handling and analysis. By using a powerful and versatile technique known as T-pattern detection and analysis (TPA) it is possible to unveil hidden relationships among the behavioural events in time. Results TPA is demonstrated to be a solid and versatile tool to study the deep structure of behaviour in different experimental contexts, both in human and non human subjects. Conclusion This re…

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Accretion in strong field gravity with eXTP

In this paper we describe the potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission for studies related to accretion flows in the strong field gravity regime around both stellar-mass and supermassive black-holes. eXTP has the unique capability of using advanced 'spectral-timing-polarimetry' techniques to analyze the rapid variations with three orthogonal diagnostics of the flow and its geometry, yielding unprecedented insight into the inner accreting regions, the effects of strong field gravity on the material within them and the powerful outflows which are driven by the accretion process.

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A self-consistent approach to the hard and soft states of 4U 1705-44

We analyzed two XMM-Newton observations of the bright atoll source 4U 1705-44, which can be considered a prototype of the class of the persistent NS LMXBs showing both hard and soft states. The first observation was performed when the source was in a hard low flux state, the second during a soft, high-flux state. Both the spectra show broad iron emission lines. We fit the spectra using a two-component model, together with a reflection model specifically suited to the case of a neutron star, where the incident spectrum has a blackbody shape. In the soft state, the reflection model, convolved with a relativistic smearing component, consistently describes the broad features present in the spec…

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The Large Area Detector of LOFT: the Large Observatory for X-ray Timing

LOFT (Large Observatory for X-ray Timing) is one of the five candidates that were considered by ESA as an M3 mission (with launch in 2022-2024) and has been studied during an extensive assessment phase. It is specifically designed to perform fast X-ray timing and probe the status of the matter near black holes and neutron stars. Its pointed instrument is the Large Area Detector (LAD), a 10 m 2 -class instrument operating in the 2-30keV range, which holds the capability to revolutionise studies of variability from X-ray sources on the millisecond time scales. The LAD instrument has now completed the assessment phase but was not down-selected for launch. However, during the assessment, most o…

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Multivariate temporal pattern analysis applied to the study of rat behavior in the elevated plus maze: Methodological and conceptual highlights

Aim of this article is to illustrate the application of a multivariate approach known as t-pattern analysis in the study of rat behavior in elevated plus maze. By means of this multivariate approach, significant relationships among behavioral events in the course of time can be described. Both quantitative and t-pattern analyses were utilized to analyze data obtained from fifteen male Wistar rats following a trial 1 - trial 2 protocol. In trial 2, in comparison with the initial exposure, mean occurrences of behavioral elements performed in protected zones of the maze showed a significant increase counterbalanced by a significant decrease of mean occurrences of behavioral elements in unprote…

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Brain histamine and oleoylethanolamide restore behavioral deficits induced by chronic social defeat stress in mice.

The physiological mechanisms underlying the complex interplay between life stressors and metabolic factors is receiving growing interest and is being analyzed as one of the many factors contributing to depressive illness. The brain histaminergic system modulates neuronal activity extensively and we demonstrated that its integrity is necessary for peripheral signals such as the bioactive lipid mediator oleoylethanolamide (OEA) to exert its central actions. Here, we investigated the role of brain histamine and its interaction with OEA in response to chronic social defeat stress (CSDS), a preclinical protocol widely used to study physio-pathological mechanisms underlying symptoms observed in d…

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Timing techniques applied to distributed modular high-energy astronomy: the H.E.R.M.E.S. project

The HERMES-TP/SP (High Energy Rapid Modular Ensemble of Satellites -- Technologic and Scientific Pathfinder) is an in-orbit demonstration of the so-called distributed astronomy concept. Conceived as a mini-constellation of six 3U nano-satellites hosting a new miniaturized detector, HERMES-TP/SP aims at the detection and accurate localisation of bright high-energy transients such as Gamma-Ray Bursts. The large energy band, the excellent temporal resolution and the wide field of view that characterize the detectors of the constellation represent the key features for the next generation high-energy all-sky monitor with good localisation capabilities that will play a pivotal role in the future …

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BeppoSAX observation of 4U 1705-44: detection of hard X-ray emission in the soft state

4U 1705-44 is one of the best studied type I X-ray burster and atoll sources. Since it covers a wide range in luminosity (from a few to 50 x 10^{36} erg s^{-1}) and shows clear spectral state transitions, it represents a good laboratory to test the accretion models proposed for atoll sources. We analysed the energy spectrum accumulated with BeppoSAX observations (43.5 ksec) in August 2000 when the source was in a soft spectral state. The continuum of the wide band energy spectrum is well described by the sum of a blackbody (kT_{bb}~0.56 keV) and a Comptonized component (seed-photon temperature kT_W~1 keV, electron temperature kT_e~2.7 keV, and optical depth ~11). A hard tail was detected at…

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Learning influence on the behavioral structure of rat response to pain in hot-plate

Aim of the research was to study, by means of descriptive and multivariate analyses, whether, and how, learning influences the behavioral structure of rat response to pain. To this purpose, a hot-plate test daily repetition procedure was carried out on male Wistar rats for five days. A 6-day interval without stimulation elapsed before last test was carried out on day 12. After composition of an ethogram, descriptive (number, latency, per cent distribution) and multivariate analyses (cluster, stochastic) were carried out for each scheduled test day. One-way ANOVA and Newman-Keuls post-hoc test for multiple comparisons revealed significant changes for climbing, jumping, front-paw licking and …

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The scientific payload on-board the HERMES-TP and HERMES-SP CubeSat missions

HERMES (High Energy Rapid Modular Ensemble of Satellites) Technological and Scientific pathfinder is a space borne mission based on a LEO constellation of nano-satellites. The 3U CubeSat buses host new miniaturized detectors to probe the temporal emission of bright high-energy transients such as Gamma-Ray Bursts (GRBs). Fast transient localization, in a field of view of several steradians and with arcmin-level accuracy, is gained by comparing time delays among the same event detection epochs occurred on at least 3 nano-satellites. With a launch date in 2022, HERMES transient monitoring represents a keystone capability to complement the next generation of gravitational wave experiments. In t…

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Time domain astronomy with the THESEUS satellite

THESEUS is a medium size space mission of the European Space Agency, currently under evaluation for a possible launch in 2032. Its main objectives are to investigate the early Universe through the observation of gamma-ray bursts and to study the gravitational waves electromagnetic counterparts and neutrino events. On the other hand, its instruments, which include a wide field of view X-ray (0.3-5 keV) telescope based on lobster-eye focussing optics and a gamma-ray spectrometer with imaging capabilities in the 2-150 keV range, are also ideal for carrying out unprecedented studies in time domain astrophysics. In addition, the presence onboard of a 70 cm near infrared telescope will allow simu…

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Evolution of Pediatric Migraine Patients Admitted at an Emergency Department after a 10-Year Follow-Up

Background: Despite its high prevalence, the clinical course of pediatric migraine has not been fully understood, and previous studies present conflicting results. We present here the findings of a 10-year follow-up study involving children with severe migraine pain admitted to our emergency department. Furthermore, all studies were carried out on selected outpatient clinical case studies. Our aim was to evaluate a population of migraine children admitted to an emergency department because of increased severity or frequency of pain or even because of very anxious parents concerning their child’s headache in order to describe their long-term outcomes, whether it differed from that of o…

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Prevalence, management, and outcome of adverse rhythm disorders in takotsubo syndrome: insights from the international multicenter GEIST registry

One important complication related to takotsubo syndrome (TTS) is adverse rhythm disorders. Our study was conducted to determine the incidence and management of adverse rhythm disorders in TTS and its long-term prognostic impact. We analyzed 906 TTS patients from 9 European centers. Patients were divided into the adverse rhythm disorders group (encompassing ventricular tachycardia, ventricular fibrillation, torsade de pointes, and asystole or complete atrioventricular block) and non-adverse rhythm disorders group. In our study cohort, we identified 67 (7.4%) patients with presence of adverse rhythm disorders. TTS patients were followed up over a period of 2.8 years. In the adverse rhythm di…

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The wide-field imager for IXO: status and future activities

The Wide Field Imager (WFI) of the International X-ray Observatory (IXO) is an X-ray imaging spectrometer based on a large monolithic DePFET (Depleted P-channel Field Effect Transistor) Active Pixel Sensor. Filling an area of 10 x 10 cm2 with a format of 1024 x 1024 pixels it will cover a field of view of 18 arcmin. The pixel size of 100 x 100 μm2 corresponds to a fivefold oversampling of the telescope's expected 5 arcsec point spread function. The WFI's basic DePFET structure combines the functionalities of sensor and integrated amplifier with nearly Fano-limited energy resolution and high efficiency from 100 eV to 15 keV. The development of dedicated control and amplifier ASICs allows for…

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Combining Quantitative and Qualitative Data in the Study of Feeding Behavior in Male Wistar Rats

The first step in a behavioral study is represented by the organization of a suitable ethogram, that is, a formal description of individual components of the behavior. Then, each component of such a behavioral repertoire can be quantified (e.g., how many times it occurs, its duration, percent distribution, latency, etc.). However, it is our contention that the possibility to describe the behavior of a living being by means of hundreds or even thousands of numbers concerning isolated components, disjointed from the comprehensive behavioral architecture, does not imply the possibility to use those numbers to reconstruct the meaning of behavior. Such a level of comprehension requires a qualita…

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The non-aromatizable androgen dihydrotestosterone (DHT) facilitates sexual behavior in ovariectomized female rats primed with estradiol

Abstract It is still unclear whether Testosterone (T) increases sexual desire through a stimulation of the androgen receptor in relevant brain regions or through its conversion to estrogens. The aim of this study was to clarify the mechanisms of T facilitation of female sexual desire by assessing the effect of a non-aromatizable androgen (Dihydrotestosterone, DHT) in a validated animal model. Ovariectomized (OVX) Long-Evans rats were treated with oil (O) + O, 10 mcg Estradiol Benzoate (EB) + O, 10 mcg EB + 500 mcg Progesterone (P), O + 500 mcg DHT or 10 mcg EB + 500 mcg DHT (n = 12 per group). EB was administered 48 h, while P and DHT 4 h, prior to 4 sexual behavioral testing sessions in bi…

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The Large Observatory For x-ray Timing

The Large Observatory For x-ray Timing (LOFT) was studied within ESA M3 Cosmic Vision framework and participated in the final down-selection for a launch slot in 2022-2024. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument, LOFT will study the behaviour of matter under extreme conditions, such as the strong gravitational field in the innermost regions of accretion flows close to black holes and neutron stars, and the supra-nuclear densities in the interior of neutron stars. The science payload is based on a Large Area Detector (LAD, 10 m 2 effective area, 2-30 keV, 240 eV spectral resolution, 1 deg collimated field of view) and a WideFi…

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Microstructural assessment of rodent behavior in the hole-board experimental assay

The aim of the present methodological article was to assess whether a microstructure of hole-exploratory activity can be demonstrated in rats tested in the hole-board, an experimental assay widely used to study anxiety-related behaviors in rodents. Six never properly described hole exploratory behavioral components were identified: active-dip, static-dip, rapid-dip, circular-sniff, point-sniff and central-sniff. Results, assessed by means of descriptive and multivariate approaches, reveal a complex microstructural organization of these behavioral elements. The hypothesis of an important role of the relationships between point-sniff and head dipping activities, in anxiety-related hole explor…

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Broadband observations of the X-ray burster 4U1705-44 with Beppo SAX

4U 1705-44 is one of the most-studied type I X-ray burster and Atoll sources. This source represents a perfect candidate to test different models proposed to self-consistently track the physical changes occurring between different spectral states because it shows clear spectral state transitions. The broadband coverage, the sensitivity and energy resolution of the BeppoSAX satellite offers the opportunity to disentangle the components that form the total X-ray spectrum and to study their changes according to the spectral state. Using two BeppoSAX observations carried out in August and October 2000, respectively, for a total effective exposure time of about 100 ks, we study the spectral evol…

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Microstructure of rat behavioral response to anxiety in hole-board

Aim of present research was to assess, by means of descriptive and multivariate approaches, in Wistar rats tested in hole-board apparatus, whether a microstructure of hole exploratory behavior may be identified in the behavioral response to anxiety. Two groups of 15 subjects were tested: one received 1 ml of saline IP and one was IP injected with diazepam at 0.5 mg/kg dissolved in 1 ml of saline. Following saline, six not yet reported hole-exploratory components were identified: active-dip, static-dip, rapid-dip, circular-sniff, point-sniff and central-sniff. Diazepam provoked significant changes of their per cent distribution. Results of multivariate analyses revealed a complex microstruct…

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Prevalence and Prognostic Impact of Diabetes in Takotsubo Syndrome: Insights From the International, Multicenter GEIST Registry

OBJECTIVE In view of low prevalence rates, diabetes is discussed as a protective factor for the occurrence of Takotsubo syndrome (TTS). Furthermore, it was associated with improved outcome in a small single-center analysis. Therefore, this study assessed the prevalence and prognostic relevance of concomitant diabetes in TTS. RESEARCH DESIGN AND METHODS A total of 826 patients with TTS were enrolled in an international, multicenter, registry-based study (eight centers in Italy and Germany). All-cause mortality was compared between patients with diabetes and patients without diabetes, and the independent predictive value of diabetes was evaluated in multivariate regression analysis. RESULTS …

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The enhanced X-ray Timing and Polarimetry mission—eXTP

In this paper we present the enhanced X-ray Timing and Polarimetry mission - eXTP. eXTP is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The mission aims at determining the equation of state of matter at supra-nuclear density, measuring effects of QED, and understanding the dynamics of matter in strong-field gravity. In addition to investigating fundamental physics, eXTP will be a very powerful observatory for astrophysics that will provide observations of unprecedented quality on a variety of galactic and extragalactic objects. In particular, its wide field monitoring capabilities will be highly instrumental to det…

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The pre-outburst flare of the A 0535+26 August/September 2005 outburst

We study the spectral and temporal behavior of the High Mass X-ray Binary A 0535+26 during a `pre-outburst flare' which took place ~5 d before the peak of a normal (type I) outburst in August/September 2005. We compare the studied behavior with that observed during the outburst. We analyse RXTE observations that monitored A 0535+26 during the outburst. We complete spectral and timing analyses of the data. We study the evolution of the pulse period, present energy-dependent pulse profiles both at the initial pre-outburst flare and close to outburst maximum, and measure how the cyclotron resonance-scattering feature (hereafter CRSF) evolves. We present three main results: a constant period P=…

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Preliminary assessment of the ATHENA/WFI non-X-ray background

We present a preliminary assessment of the non-X-ray background for the WFI on board ATHENA conducted at IAAT in the context of the collaborative background and radiation damage working group activities. Our main result is that in the baseline configuration originally assumed for the camera the requirement on the level of non-X-ray background could not be met. In light of the results of Geant4 simulations we propose and discuss a possible optimization of the camera design and pinpoint some open issues to be addressed in the next phase of investigation. One of these concerns the possible contribution to the non-X-ray background from soft protons and ions funneled to the focal plane through t…

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The polarization dependence of x‐ray photoelectron yield of a Au photocathode

We report a measurement of the total photoelectron yield of gold as a function of the incident x‐ray polarization. Polarized x rays with energies of 2.5, 2.7, and 4.0 keV were used to excite a gold photocathode at a glancing incidence angle between 5° and 50°. Contrary to a previous report, we found no measurable polarization dependence for all three x‐ray energies. We conclude that the modulation factor, i.e., the fractional change of the total yield when the polarization state is varied, is less than 4%.

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The effects of diazepam on the behavioral structure of the rat's response to pain in the hot-plate test: Anxiolysis vs. pain modulation

The aim of the present study was to evaluate, by means of quantitative and multivariate analyses, the effects of diazepam on the behavioral structure of the rat's response to pain in the hot-plate test as well as whether such changes are associated with drug-induced effects on anxiety and/or nociception. To this purpose, ten groups of male Wistar rats were intraperitoneally injected with saline, diazepam (0.25, 0.5 and 2 mg/kg), FG-7142 (1, 4 and 8 mg/kg) or morphine (3, 6 and 12 mg/kg). The mean number and mean latency to first appearance were calculated for each behavioral component. In addition, multivariate cluster and adjusted residual analyses based on the elaboration of transition ma…

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Idiopathic Non-Dental Facial Pain Syndromes in Italian Children: A Clinical Case Series

Background. The orofacial pain syndromes (OFPs) are a heterogeneous group of syndromes characterized by painful attacks involving the orofacial structures. They may be summarily subdivided into two great categories: (1) orofacial pain mainly attributed to dental disorders such as dentoalveolar and myofascial orofacial pain or temporomandibular joint (TM) pain; (2) orofacial pain mainly attributed to non-dental pain as neuralgias, facial localization of primary headaches or idiopathic orofacial pain. The second group is uncommon, often described by single case reports, can often show overlapping symptoms with the first group, and represents a clinical challenge, carrying the risk of underval…

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Observatory science with eXTP

Disponible preprint en: arXiv:1812.04023v1 [astro-ph.HE] [v1] Mon, 10 Dec 2018 19:00:52 UTC (4,376 KB)

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Chronic inflammation: A key role in degeneration of bicuspid aortic valve.

Abstract Introduction Bicuspid aortic valve (BAV) is the most common congenital valvular heart defect resulting from abnormal aortic cusp formation during heart development, where two of the three normal and equal sized cusps fuse into a single large cusp resulting in a two cusps aortic valve. Over the past years, much interest has been given in understanding the pathogenesis of BAV and its complications. In this review, we focused on the role of inflammation, involved in the degeneration of BAV and the development of its complications. Role of inflammation From a pathophysiological point of view, BAV may rapidly progress into aortic stenosis (AS) and is related to aortopathy. Several histo…

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Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign

Full list of authors: EHT MWL Science Working Group; Algaba, J. C.; Anczarski, J.; Asada, K.; Baloković, M.; Chandra, S.; Cui, Y. -Z.; Falcone, A. D.; Giroletti, M.; Goddi, C.; Hada, K.; Haggard, D.; Jorstad, S.; Kaur, A.; Kawashima, T.; Keating, G.; Kim, J. -Y.; Kino, M.; Komossa, S.; Kravchenko, E. V.; Krichbaum, T. P.; Lee, S. -S.; Lu, R. -S.; Lucchini, M.; Markoff, S.; Neilsen, J.; Nowak, M. A.; Park, J.; Principe, G.; Ramakrishnan, V.; Reynolds, M. T.; Sasada, M.; Savchenko, S. S.; Williamson, K. E.; Event Horizon Telescope Collaboration; Akiyama, Kazunori; Alberdi, Antxon; Alef, Walter; Anantua, Richard; Azulay, Rebecca; Baczko, Anne-Kathrin; Ball, David; Barrett, John; Bintley, Dan; …

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Takotsubo Cardiomyopathy: One More Angiographic Evidence of Microvascular Dysfunction

Background Takotsubo cardiomyopathy (TC) aetiology has not been completely understood yet. One proposed pathogenic mechanism was coronary microvascular dysfunction (MVD). This study compared coronary flow and myocardial perfusion in patients with TC, microvascular angina (MVA), and a control group (CG). Methods Out of 42 consecutive patients presented to our centre with TC from 2013 to 2017; we retrospectively selected 27 patients. We compared them with a sex- and age-matched group of 27 MVA cases and 27 patients with normal coronary arteries (CG). The flow was evaluated in the three coronary arteries as TIMI flow and TIMI frame count (TFC). Myocardial perfusion was studied with Blush-Score…

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Pediatric haedaches epidemiology in emergency department during COVID-19

Background and aims Recent studies have showed that in emergency department (ED) pediatric admissions for headache are increasing in the last years. However Covid-19 pandemic may have changed the use of health services for several reasons. Aim of this study is to analyze the rates of admission for pediatric headaches in ED before and during Covid19 Pandemic. Methods we have collected retrospectively the records of children (range of age 5–14) admitted on ED in 2012, 2019 and 2020. We selected the records including Headache and Headache associated to other symptoms (vomit, fever, dizziness, etc.), collecting further the use of computed tomography (CT) and neurological consultation. Results I…

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The impact of chronic daily nicotine exposure and its overnight withdrawal on the structure of anxiety-related behaviors in rats: Role of the lateral habenula.

Tobacco smoking is a serious health problem worldwide and a leading cause of mortality. Nicotine, the addictive component of tobacco, affects a range of emotional responses, including anxiety-related behaviors. Although perceived by smokers to be anxiolytic, evidence suggests that smoking increases anxiety and that mood fluctuates with nicotine intake. Thus, nicotine addiction may depend on easing the psychobiological distress caused by its abuse. The lateral habenula (LHb) has been implicated as a neural substrate for acute nicotine-induced anxiety, but its role in anxiety-like behaviors associated with chronic nicotine exposure has not been explored. Here, we assessed the effect of chroni…

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Different Representation Procedures Originated from Multivariate Temporal Pattern Analysis of the Behavioral Response to Pain in Wistar Rats Tested in a Hot-Plate under Morphine

Temporal pattern analysis is an advanced multivariate technique able to investigate the structure of behavior by unveiling the existence of statistically significant constraints among the interval length separating events in sequence. If on the one hand, such an approach allows investigating the behavioral response to pain in its most intimate and inner features, on the other hand, due to the meaning of the studies on pain, it is of relevant importance that the results utilize intuitive and easily comprehensible ways of representation. The aim of this paper is to show various procedures useful to represent the results originating from the multivariate T-pattern analysis of the behavioral re…

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Behavioral fragmentation in the D1CT-7 mouse model of Tourette's syndrome.

Aim The transgenic D1CT-7 mouse is one of the best-characterized animal models of Tourette's syndrome (TS), exhibiting spontaneous tic-like Head-Body Twitches (HBT) and deficits in sensorimotor gating. This study is aimed at evaluating the behavioral dynamics of these mutants and their potential relevance to TS. Methods The behavior of D1CT-7 and Wild Type littermates was firstly assessed by considering frequencies and durations. To detect recurrent real-time behavioral sequences, the multivariate T-pattern analysis was employed. Analyses of transition probabilities among behaviors further provided an overall picture of the behavioral dynamics. Results T-patterns and transition matrices rev…

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The THESEUS space mission concept: science case, design and expected performances

THESEUS is a space mission concept aimed at exploiting Gamma-Ray Bursts for investigating the early Universe and at providing a substantial advancement of multi-messenger and time-domain astrophysics. These goals will be achieved through a unique combination of instruments allowing GRB and X-ray transient detection over a broad field of view (more than 1sr) with 0.5¿1 arcmin localization, an energy band extending from several MeV down to 0.3¿keV and high sensitivity to transient sources in the soft X-ray domain, as well as on-board prompt (few minutes) follow-up with a 0.7¿m class IR telescope with both imaging and spectroscopic capabilities. THESEUS will be perfectly suited for addressing …

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The Large Area Detector onboard the eXTP mission

The eXTP (enhanced X-ray Timing and Polarimetry) mission is a major project of the Chinese Academy of Sciences (CAS) and China National Space Administration (CNSA) currently performing an extended phase A study and proposed for a launch by 2025 in a low-earth orbit. The eXTP scientific payload envisages a suite of instruments (Spectroscopy Focusing Array, Polarimetry Focusing Array, Large Area Detector and Wide Field Monitor) offering unprecedented simultaneous wide-band X-ray spectral, timing and polarimetry sensitivity. A large European consortium is contributing to the eXTP study and it is expected to provide key hardware elements, including a Large Area Detector (LAD). The LAD instrumen…

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Dense matter with eXTP

In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry (eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cannot be replicated in a terrestrial laboratory. The tightest statistical constraints on the dense matter equation of state will come from pulse profile modelling of accretion-powered pulsars, burst oscillation sources, and rotation-powered pulsars. Additional constraints will derive from spin measurements, burst spectra, and properties of the accretion flows in the vicinity of the neutron star. Under development by an international Consortium led by the Institute of High Energy Physics o…

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Effects of the benzodiazepine inverse agonist FG7142 on the structure of anxiety-related behavior of male Wistar rats tested in hole board

Little is known about the structural characteristics of the behavior of rats with enhanced anxiety level. To fill this gap, a study was undertaken where effects of an anxiogenic drug were examined on behavioral structure of rats tested in hole board.This study investigates effects of increased anxiety level on the structure of the behavior of rats tested in hole board METHODS: Different doses of FG7142 (1, 4, 8 mg/kg IP), a potent anxiety-inducing drug, were administered to three groups of male Wistar rats. A further group was administered saline. Experiments were recorded through a digital camera. Quantitative and multivariate approaches were applied.Percent distributions and durations sho…

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Discovering hidden temporal patterns in behavior and interaction : t-pattern detection and analysis with THEME

In our laboratories we use T-pattern analysis to study rat behavior in different and well-known experimental assays widely employed as rodent models of anxiety: the open field, the hole board and the elevated plus maze. By using Theme software and T-pattern analysis, we have observed that numerous events, characterizing rodent behavior in each experimental model, occurred sequentially and with significant constraints on the interval lengths separating them. In this chapter, for each test, we highlight some key aspects of our behavioral analyses, with a twofold attempt: first to provide the researcher with useful information concerning the application of T-pattern analysis in the study of ro…

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A relativistic iron emission line from the neutron star low-mass X-ray binary GX 3+1

We present the results of a spectroscopic study of the Fe K{\alpha} emission of the persistent neutron-star atoll low-mass X-ray binary and type I X-ray burster GX 3+1 with the EPIC-PN on board XMM-Newton. The source shows a flux modulation over several years and we observed it during its fainter phase, which corresponds to an X-ray luminosity of Lx~10^37 ergs/s. When fitted with a two-component model, the X-ray spectrum shows broad residuals at \sim6-7 keV that can be ascribed to an iron K{\alpha} fluorescence line. In addition, lower energy features are observed at \sim3.3 keV, \sim3.9 keV and might originate from Ar XVIII and Ca XIX. The broad iron line feature is well fitted with a rela…

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