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Measuring a pulsar's rotational evolution is crucial to understanding the nature of the pulsar. Here we provide updated timing models for the rotational evolution of six pulsars, five of which are rotation phase-connected using primarily NICER X-ray data. For the newly-discovered fast energetic young pulsar, PSR J0058-7218, we increase the baseline of its timing model from 1.4 days to 8 months and not only measure more precisely its spin-down rate nudot = (-6.2324+/-0.0001)x10^-11 Hz s^-1 but also for the first time the second time derivative of spin rate nuddot = (4.2+/-0.2)x10^-21 Hz s^-2. For the fastest and most energetic young pulsar, PSR J0537-6910 (with 16 ms spin period), we detect 4 more glitches, for a total of 15 glitches over 4.5 years of NICER monitoring, and show that its spin-down behavior continues to set this pulsar apart from all others, including a long-term braking index n = -1.234+/-0.009 and interglitch braking indices that asymptote to, 18 pages, 17 figures; accepted for publication in ApJ; very minor edits and no changes to numbers

Purpose This paper aims to investigate the strategic governance of the digital transformation of the accounting environment in cultural organizations, with a specific focus on practices of social responsibility and stakeholder engagement in virtual museums. Design/Methodology/Approach By adopting a multiple case study approach, this study investigated five Italian virtual museums and their digitalization processes. Data were collected and triangulated from multiple sources, including documentary analysis and semi-structured interviews with 16 key informants. Findings Considering the digitalization of the accounting environment as a paradigmatic change, the authors identify three key transitions for its strategic governance: from the static, technical and physical to the relational, emotional and digital; from bureaucratic managerialism to value cocreation; and from traditional CSR to integrated external engagement. Moreover, the authors found that social responsibility and stakeholder engagement practices are used in a limited way, and that the use of social media appears to be increasingly important and to be carried out through an emergent rather than a deliberate strategy. Research Limitations/Implications The paper draws from a limited sample of case studies in one country and is based on exploratory research. This paper calls for more comparative studies using a longitudinal approach to investigate the impacts of digitalization on the accounting environment of cultural organizations. Originality/Value This study is one of the few studies concentrating on the effects of digitalization on the accounting environment of cultural organizations.

We report here on the discovery with XMM–Newton of pulsations at 22 ms from the central compact source associated with IKT 16, a supernova remnant in the Small Magellanic Cloud (SMC). The measured spin period and spin period derivative correspond to 21.7661076(2) ms and 2.9(3) × 10−14 s s−1, respectively. Assuming standard spin-down by magnetic dipole radiation, the spin-down power corresponds to 1.1 × 1038 erg s−1 implying a Crab-like pulsar. This makes it the most energetic pulsar discovered in the SMC so far and a close analogue of PSR J0537–6910, a Crab-like pulsar in the Large Magellanic Cloud. The characteristic age of the pulsar is 12 kyr. Having for the first time a period measure for this source, we also searched for the signal in archival data collected in radio with the Parkes telescope and in γ-rays with the Fermi/LAT, but no evidence for pulsation was found in these energy bands.

This paper investigates the effect of ownership on sustainable development and environmental policy in Italian municipally owned corporations (MOCs) dealing with urban waste management, trying to understand if multiple ownership can generate better performance compared to single ownership and if the presence of private partners could be crucial in this. The research question is answered by analyzing 41 MOCs of the largest Italian cities operating in urban waste management. In this specific sector, public administrations have tried to improve their offer in terms of sustainable development, environmental policy, and efficiency. The paper covers the Italian case study, where urban waste production per capita is higher than the European average figure. The waste cycle management service is operated in Italy at local level through totally publicly owned companies (monoadministration or multiadministration), mixed (public–private) companies, or via a full externalization achieved by means of public tenders. Through a multinomial ordered probit panel, we show that MOCs with multiple owners perform better than those having a single owner and perform much better with the presence of a private partner, confirming those academic findings according to which collaborative arrangements can increase efficiency, do better than public sector bureaucracy, and lower the costs of service provision. The results of this paper can be used by academics, practitioners, and policy makers alike. To the best of our knowledge, this is the only study that applies this perspective to the analysis of the current international waste management scenario with relation to MOCs having multiple ownerships.

Purpose The purpose of this study is the motor outcome analysis of early Botulinum toxin (BT) treatment in patients affected by large-angle infantile esotropia (IE). Patients and methods Retrospective analysis of 130 medical charts of IE patients who underwent BT injections between 2004 and 2019 was performed. All patients underwent BT injections within 13 months of age. Results Thirty patients, matching the inclusion criteria, were included in the study. Twenty-eight patients showing residual ET ≥25 PD (34.3±6.6 PD ranged from 25 to 50) underwent surgery. Conclusion Our result after 1 Botulinum toxin injection showed a very low success rate (6.7%) at last follow-up (28.3±7.2 months). Our data would suggest one Botulinum toxin injection in children affected by large-angle infantile esotropia allows a significant reduction of deviation but does not avoid the need for surgical treatment.

In the past few years, nonfinancial reporting has been a widely debated issue in literature, not the least because of its importance during times in which topics such as climate change and social transformations have become strategic issues particularly for larger companies. Recent regulatory changes within the European legal framework have marked the transition from a voluntary nonfinancial reporting system to a mandatory one for larger companies. Unlike the case of manufacturing companies, the debate surrounding the application of CSR policies in the banking industry has not been as univocal. Taking into account a case study, we how such pressure is neither strictly positive nor negative, but it can rather be defined as a stimulating inertia, able to indicate prompt and sure strategic directions for the Company, to be pursued in a sustainable manner. This will need the implementation of internationally acknowledged policies and procedures regulating the interactions between the Company and its stakeholders.

We have studied the unusual time variability of an ultraluminous X-ray source in M 101, 4XMM J140314.2$+$541806 (henceforth, J1403), using Chandra and XMM-Newton data. Over the last two decades, J1403 has shown short-duration outbursts with an X-ray luminosity $\sim1-3 \times 10^{39}$ erg s$^{-1}$, and longer intervals at luminosities $\sim0.5-1 \times 10^{38}$ erg s$^{-1}$. The bimodal behaviour and fast outburst evolution (sometimes only a few days) are more consistent with an accretor/propeller scenario for a neutron star than with the canonical outburst cycles of stellar-mass black holes. If this scenario is correct, the luminosities in the accretor and propeller states suggest a fast spin ($P \approx$ 5 ms) and a low surface magnetic field ($B \sim 10^{10}$ G), despite our identification of J1403 as a high-mass X-ray binary. The most striking property of J1403 is the presence of strong $\sim$600-s quasi periodic oscillations (QPOs), mostly around frequencies of $\approx 1.3-1.8$ mHz, found at several epochs during the ultraluminous regime. We illustrate the properties of such QPOs, in particular their frequency and amplitude changes between and within observations, with a variety of techniques (Fast Fourier Transforms, Lomb-Scargle periodograms, weighted wavelet Z-transform analysis). The QPO frequency range $, Comment: 23 pages, 29 figures, 5 tables. Accepted for publication in MNRAS

Literature on performance measurement in waste management service, usually considers assessment tools and methods that focus only on a specific dimension of performance and lacks methods and models that simultaneously consider more dimensions. In this study, adopting the fuzzy logic expert system, we propose a performance measurement model that simultaneously considers three performance dimensions: profitability, financial characteristics and efficiency. To show its empirical implementation, a quantitative analysis was developed regarding the service provided in the 106 Italian provincial capitals that have different owner structures (private, public and mixed). As output, the fuzzy logic system approach adopted generated a rating for the assessment of the performance of the entities, and then a ranking of the cities based on the same. The main results show that: 1) the public owned companies that provide the waste management service have an overall better performance than those with private or mixed ownerships; 2) cities that entrust the waste management service to the same company do not occupy an adjacent position in the ranking. As practical implications, the proposed model can help public administrators: a) to control the outcomes of their entities (as the TARI); b) to make a decision whether to provide solid waste management services directly or through a private entity chosen to provide the service in return for a negotiated fee; c) to compare waste management services provided in different cities in an objective way and to monitor their performance over time, with the aim of achieving continuous improvement. The model's outcomes are useful to assist public managers and politicians in assessing the compliance level of performance goals related to the solid waste service; while the overall performance index is a useful tool to assist the decision-making process leading to change either fully or partially, their nature from public to mixed or private. The proposed method is able to formalize and automate the decision-making process concerning the evaluation of the performance of waste management, reducing the distortions of the political and environmental context.

Aim: The aim was to evaluate the long-term motor outcome of superior rectus transposition procedure in patients affected by unilateral esotropic Duane retraction syndrome with residual esotropia and anomalous head position. Methods: A retrospective analysis of medical records of patients affected by esotropic Duane retraction syndrome who underwent superior rectus transposition procedure as reoperation for residual esotropia and/or residual anomalous head position. Amount of deviation, anomalous head position, duction limitation, globe retraction, presence of upshoot/downshoot, and vertical deviation were analyzed before and after superior rectus transposition procedure. Results: Twenty patients were selected. All patients underwent unilateral medial rectus recession or bilateral medial rectus recession, for unilateral esotropic Duane retraction syndrome at least 2 years before superior rectus transposition reoperation. Mean age at surgery (superior rectus transposition) was 12 ± 6.8 years, and the follow-up period was 2.7 ± 0.6. Mean deviations at distance and near before surgery were 19.5 ± 5.7 and 15.2 ± 6.8, respectively. Two patients showed upshoot. Head turn was 11.4 ± 5.1°; abduction limitation was −2.6 ± 0.9. After superior rectus transposition, all patients showed an improvement of esotropia at distance and near (8.1 ± 5.7 and 5.1 ± 5.6, respectively; p Conclusion: Superior rectus transposition procedure is an effective procedure in esotropic Duane retraction syndrome patients who previously undergone unilateral/bilateral medial rectus recession, with residual esotropia and anomalous head position. It allows improvement of esotropia, head turn, and partial recovery of abduction in a significant percentage of patients (30%) with no vertical complications.

This paper addresses the possibility to exploit Enhanced Vision Systems (EVS) for landing operations within the Urban Air Mobility (UAM) framework. First, an analysis of sensing requirements is carried out in terms of sensors’ Field of View (FOV), operational range, resolution, and frame rate. These requirements are estimated considering different factors such as airspace structure and possible landing trajectories, navigation performance, and wind conditions. A preliminary assessment of the level of maturity of the available technologies is obtained as a result of the comparison of the EVS state of the art and the estimated visual requirements for the UAM scenarios. Finally, the performance of sensing systems fulfilling the previously defined requirements is assessed within a numerical simulation framework able to realistically reproduce UAM landing scenarios including trajectory/attitude disturbances. Specifically, visual-based techniques for pose estimation with respect to a vertiport are developed and then integrated within a multi-sensor fusion architecture combining other sources such as inertial sensors.

We report on the follow-up $XMM-Newton$ observation of the persistent X-ray pulsar CXOU J225355.1+624336, discovered with the CATS@BAR project on archival $Chandra$ data. The source was detected at $f_{\rm X}$(0.5-10 keV) = 3.4$\times 10^{-12}$ erg cm$^{-2}$ s$^{-1}$, a flux level which is fully consistent with the previous observations performed with $ROSAT$, $Swift$, and $Chandra$. The measured pulse period $P$ = 46.753(3) s, compared with the previous measurements, implies a constant spin down at an average rate $\dot P = 5.3\times 10^{-10}$ s s$^{-1}$. The pulse profile is energy dependent, showing three peaks at low energy and a less structured profile above about 3.5 keV. The pulsed fraction slightly increases with energy. We described the time-averaged EPIC spectrum with four different emission models: a partially covered power law, a cut-off power law, and a power law with an additional thermal component (either a black body or a collisionally ionized gas). In all cases we obtained equally good fits, so it was not possible to prefer or reject any emission model on the statistical basis. However, we disfavour the presence of the thermal components, since their modeled X-ray flux, resulting from a region larger than the neutron star surface, would largely dominate the X-ray emission from the pulsar. The phase-resolved spectral analysis showed that a simple flux variation cannot explain the source variability and proved that it is characterized by a spectral variability along the pulse phase. The results of the $XMM-Newton$ observation confirmed that CXOU J225355.1+624336 is a BeXB with a low-luminosity ($L_{\rm X} \sim 10^{34-35}$ erg s$^{-1}$), a limited variability, and a constant spin down. Therefore, they reinforce the source classification as a persistent BeXB., 8 pages, 3 tables, 7 figures. Accepted for publication in Astronomy and Astrophysics on 19/04/2021. File replaced to match the final accepted version

HD49798 / RXJ0648.0-4418 is the only confirmed X-ray binary in which the mass donor is a hot subdwarf star of O spectral type and, most likely, it contains a massive white dwarf (1.28$\pm$0.05 M$_{\rm SUN}$) with a very fast spin period of 13.2 s. Here we report the results of new XMM-Newton pointings of this peculiar binary, carried out in 2018 and in 2020, together with a reanalysis of all the previous observations. The new data indicate that the compact object is still spinning-up at a steady rate of $(-2.17\pm0.01)\times10^{-15}$ s s$^{-1}$, consistent with its interpretation in terms of a young contracting white dwarf. Comparison of observations obtained at similar orbital phases, far from the ecplise, shows evidence for long term variability of the hard ($>$0.5 keV) spectral component at a level of $\sim$(70$\pm$20)\%, suggesting the presence of time-dependent inhomogeneities in the weak stellar wind of the HD49798 subdwarf. To investigate better the soft spectral component that dominates the X-ray flux from this system, we computed a theoretical model for the thermal emission expected from an atmosphere with element abundances and surface gravity appropriate for this massive white dwarf. This model gives a best fit with effective temperature of T$_{\rm eff}$=2.25$\times$10$^5$ K and an emitting area with radius of $\sim$1600 km, larger than that found with blackbody fits. This model also predicts a contribution of the pulsed emission from the white dwarf in the optical band significantly larger than previously thought and possibly relevant for optical variability studies of this system., Accepted for publication on MNRAS

We report on the results of an XMM-Newton observation of the Supergiant Fast X-ray Transient (SFXT) IGR J08408-4503 performed in June 2020. The source is composed by a compact object (likely a neutron star) orbiting around an O8.5Ib-II(f)p star, LM Vel. The X-ray light curve shows a very low level of emission, punctuated by a single, faint flare. Analysis of spectra measured during the flare and during quiescence is performed. The quiescent state shows a continuum spectrum well deconvolved to three spectral models: two components are from a collisionally-ionized plasma (with temperatures kT1=0.24 keV and kT2=0.76 keV), together with a power law model (photon index of 2.55), dominating above 2 keV. The X-ray flux emitted at this lowest level is 3.2$\times10^{-13}$ erg/cm2/s (0.5-10 keV, corrected for the interstellar absorption), implying an X-ray luminosity of 1.85$\times10^{32}$ erg/s (at 2.2 kpc). The two temperature collisionally-ionized plasma is intrinsic to the stellar wind of the donor star, while the power law can be interpreted as emission due to residual, low level accretion onto the compact object. The X-ray luminosity contributed by the power law component only, in the lowest state, is (4.8$\pm{1.4})\times10^{31}$ erg/s, the lowest quiescent luminosity detected from the compact object in an SFXT. Thanks to this very faint X-ray state caught by XMM-Newton, X-ray emission from the wind of the donor star LM Vel could be well-established and studied in detail for the first time, as well as a very low level of accretion onto the compact object. The residual accretion rate onto the compact object in IGR J08408-4503 can be interpreted as the Bohm diffusion of (possibly magnetized) plasma entering the neutron star magnetosphere at low Bondi capture rates from the supergiant donor wind at the quasi-spherical radiation-driven settling accretion stage., Comment: 13 pages, 6 figures, 5 tables; accepted for publication in Astronomy & Astrophysics

The value creation potential of IC and intangible assets is acquiring a crucial role within the modern economies, especially in crisis situations and in highly competitive environments (Flamholtz & Hua, 2003), where information and knowledge represent one of the key drivers for value creation (Esposito & Ricci, 2014) and the acquisition of a lasting competitive advantage (Del Giudice et al., 2013; Murray et al., 2016). The rise of the fourth industrial revolution and the increasing social connectivity have the ability to change the way in which companies interact with their customers, employees, suppliers and partners, and is forcing companies to face new challenges. Industry 4.0 and its related technologies (the purported smart technologies) can thus exert a significant impact on IC (Edvinsson, 2013; Borin & Donato, 2015). By means of a structured lietarture review, this chapter aims at investigating how smart technologies impact on IC management as a whole and how digitalization can influence the individual components of IC.

The detection of a short hard X-ray burst and an associated bright soft X-ray source by the Swift satellite in 2020 October heralded a new magnetar in outburst, SGR J1830-0645. Pulsations at a period of ∼10.4 s were detected in prompt follow-up X-ray observations. We present here the analysis of the Swift/Burst Alert Telescope burst, of XMM-Newton and the Nuclear Spectroscopic Telescope Array observations performed at the outburst peak, and of a Swift/X-ray Telescope monitoring campaign over the subsequent month. The burst was single-peaked, lasted ∼6 ms, and released a fluence of ≈ 5 × 10-9 erg cm-2 (15-50 keV). The spectrum of the X-ray source at the outburst peak was well described by an absorbed double-blackbody model plus a power-law component detectable up to ∼25 keV. The unabsorbed X-ray flux decreased from ∼5 × 10-11 to ∼2.5 × 10-11 erg cm-2 s-1 one month later (0.3-10 keV). Based on our timing analysis, we estimate a dipolar magnetic field ≈5.5 × 1014 G at pole, a spin-down luminosity ≈2.4 × 1032 erg s-1, and a characteristic age ≈24 kyr. The spin modulation pattern appears highly pulsed in the soft X-ray band, and becomes smoother at higher energies. Several short X-ray bursts were detected during our campaign. No evidence for periodic or single-pulse emission was found at radio frequencies in observations performed with the Sardinia Radio Telescope and Parkes. According to magneto-thermal evolutionary models, the real age of SGR J1830-0645 is close to the characteristic age, and the dipolar magnetic field at birth was slightly larger, ∼1015 G., This research is based on observations with XMM-Newton (ESA/NASA), NuSTAR (CalTech/NASA/ JPL), and Swift (NASA/ASI/UKSA) and on data retrieved through the NASA/GSFCʼs HEASARC archives. The Sardinia Radio Telescope is funded by the Italian MIUR, ASI, and the Autonomous Region of Sardinia, and is operated as a National Facility by INAF. We used data collected at the Parkes radio telescope (proposal No. P1083), part of the Australia Telescope National Facility which is funded by the Australian Government for operation as a National Facility managed by CSIRO. We acknowledge the Wiradjuri people as the traditional owners of the Observatory site. F.C.Z. and A.B. are supported by Juan de la Cierva fellowships. F.C.Z., A.B., N.R., C.D., and D.V. are supported by the ERC Consolidator Grant “MAGNESIA” (No. 817661) and acknowledge funding from grants SGR2017- 1383 and PGC2018-095512-BI00. G.L.I., P.E., R.T., and A.T. acknowledge financial support from the Italian MIUR through PRIN grant 2017LJ39LM. G.L.I. also acknowledges funding from ASI-INAF agreements I/037/12/0 and 2017-14-H.O. M.B., A.P., and A.R. acknowledge financial support from the research grant “iPeska” (PI: A. Possenti) funded under the INAF national call PRIN-SKA/CTA with Presidential Decree 70/2016. A.R. acknowledges continuing valuable support from the Max-Planck Society. We acknowledge the support of the PHAROS COST Action (CA16214).

The best presentation of a nation's cultural heritage has been a recurrent theme in the scientific and cultural debate. Few studies, however, have investigated how cultural organizations are influenced by digitization when communicating corporate social responsibility. By adopting a multiple case study approach, we investigated a sample of virtual museums and their digital CSR culture. This study contributes to the literature on CSR effectiveness in cultural organizations, by focusing on how digitization is influencing the attitude toward CSR disclosure, in order to provide suggestions for cultural managers, scholars, policymakers and practitioners alike. More specifically, this paper aims to examine stakeholders' perceptions in digital cultural organizations as a new form of social responsibility. To the best of our knowledge, this is the only study that applies this perspective to the analysis of the digitization process through CSR, currently under way across cultural institutions around the world.

We report on multi-band observations of the transient source Swift J0840.7-3516, which was detected in outburst in 2020 February by the Neil Gehrels Swift Observatory. The outburst episode lasted just ∼5 days, during which the X-ray luminosity quickly decreased from LX ≈ 3 × 1037 d102 erg s-1 at peak down to LX ≈ 5 × 1033 d102 erg s-1 in quiescence (0.3-10 keV; d10 is the distance to the source in units of 10 kpc). Such x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">a marked and rapid decrease in the flux was also registered at UV and optical wavelengths. In outburst, the source showed considerable aperiodic variability in the X-rays on timescales as short as x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">a few seconds. The spectrum of the source in the energy range 0.3-20 keV was well described by x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">a thermal, blackbody-like, component plus x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">a non-thermal, power law-like, component and it softened considerably as the source returned to quiescence. The spectrum of the optical counterpart in quiescence showed broad emission features mainly associated with ionised carbon and oxygen, superposed on x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">a blue continuum. No evidence for bright continuum radio emission was found in quiescence. We discuss possible scenarios for the nature of this source and show that the observed phenomenology points to x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">a transient ultra-compact X-ray binary system. © ESO 2021., This research is based on observations made with the Gran Telescopio Canarias (GTC), installed at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias in the island of La Palma, under Director’s Discretionary Time (code GTC2020-142). The data were obtained with OSIRIS, built by a Consortium led by the Instituto de Astrofísica de Canarias in collaboration with the Instituto de Astronomía of the Universidad Autónoma de México. OSIRIS was funded by GRANTECAN and the National Plan of Astronomy and Astrophysics of the Spanish Government. We are indebted to Antonio Cabrera and the GTC staff for their efforts in performing the GTC observations. The NuSTAR mission is a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory and funded by NASA. The NICER mission operates on the International Space Station and is funded by NASA. The Australia Telescope Compact Array is part of the Australia Telescope National Facility which is funded by the Australian Government for operation as a National Facility managed by CSIRO. We acknowledge the Gomeroi people as the traditional owners of the ATCA observatory site. This research made use of: the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC) and the California Institute of Technology; software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory; IRAF, distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation; APLpy (Robitaille & Bressert 2012), an open-source plotting package for Python hosted at https://aplpy.github.io/; and Astropy (Astropy Collaboration 2013, 2018), a community-developed core Python package for Astronomy. We also made use of the following software: CASA (McMullin et al. 2007), HEASOFT v. 6.28, HENDRICS v. 5.1 (Bachetti 2018), XSPEC v. 12.11.1 (Arnaud 1996). FCZ and AB are supported by Juan de la Cierva fellowships. FCZ, AB and NR are supported by the ERC Consolidator Grant ‘MAGNESIA’ (nr. 817661) and acknowledge funding from grants SGR2017-1383 and PGC2018-095512-BI00. AdUP acknowledges funding from a Ramón y Cajal fellowship (RyC-2012-09975). TDR acknowledges financial contribution from the agreement ASI-INAF n.2017-14-H.0. We thank support from the COST Action ‘PHAROS’ (CA 16124)., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (SEV-2017-0709).

Ultraluminous X-ray sources are considered amongst the most extremely accreting objects in the local Universe. The recent discoveries of pulsating neutron stars in ULXs strengthened the scenario of highly super-Eddington accretion mechanisms on stellar mass compact objects. In this work, we present the first long-term light curve of the source NGC 4559 X7 using all the available Swift, XMM-Newton, Chandra and NuSTAR data. Thanks to the high quality 2019 XMM-Newton and NuSTAR observations, we investigated in an unprecedented way the spectral and temporal properties of NGC 4559 X7. The source displayed flux variations of up to an order of magnitude and an unusual flaring activity. We modelled the spectra from NGC 4559 X7 with a combination of two thermal components, testing also the addition of a further high energy cut-off powerlaw. We observed a spectral hardening associated with a luminosity increase during the flares, and a spectral softening in the epochs far from the flares. Narrow absorption and emission lines were also found in the RGS spectra, suggesting the presence of an outflow. Furthermore, we measured hard and (weak) soft lags with magnitudes of a few hundreds of seconds whose origin is possibly be due to the accretion flow. We interpret the source properties in terms of a super-Eddington accretion scenario assuming the compact object is either a light stellar mass black hole or a neutron star., Comment: Accepted for publication in MNRAS; 14 pages, 10 figures and 2 tables

The aim of this paper is twofold: first, it aims to analyze what kind of value is generated by hybrid organizations and how, second, it aims to understand the role of social impact assessment (SIA) in the measurement of added value, especially in terms of social and economic change generated by hybrids. Hybrid organizations are a debated topic in literature and have different strengths in responding to needs, mainly in the public interest. Nevertheless, there are not many studies that identify the impact and change generated by these organizations. After highlighting the gap in the literature, the study proposes an innovative approach that combines SIA, interview, interventionist approach and documental analysis. The breakdown of SIA through the five elements of the value chain (inputs, activities, outputs, outcomes, and impact) guarantees a linear definition of the value generated through change with procedural objectivity capable of grasping hybrid organizations’ complexity. The value generated or absorbed is the change generated by the impact measured based on the incidence of public resources allocated. Through the SIA and counterfactual approach, the civil service case study analysis highlights how the value generated by public resources can be measured or more clearly displayed in the measurement process itself.

After 15 years, in late 2018, the magnetar XTE J1810-197 underwent a second recorded X-ray outburst event and reactivated as a radio pulsar. We initiated an X-ray monitoring campaign to follow the timing and spectral evolution of the magnetar as its flux decays using Swift, XMM-Newton, NuSTAR, and NICER observations. During the year-long campaign, the magnetar reproduced similar behaviour to that found for the first outburst, with a factor of two change in its spin-down rate from $\sim7.2\times10^{-12}$ s s$^{-1}$ to $\sim1.5\times10^{-11}$ s s$^{-1}$ after two months. Unique to this outburst, we confirm the peculiar energy-dependent phase shift of the pulse profile. Following the initial outburst, the spectrum of XTE J1810-197 is well-modelled by multiple blackbody components corresponding to a pair of non-concentric, hot thermal caps surrounded by a cooler one, superposed to the colder star surface. We model the energy-dependent pulse profile to constrain the viewing and surface emission geometry and find that the overall geometry of XTE J1810-197 has likely evolved relative to that found for the 2003 event., 14 pages, 12 figures, 4 tables. Accepted for publications in MNRAS

What leadership practices can be enacted in contexts of public values failure and with low social capital to enact positive social change? This article studies public management and leadership dynamics in the "Land of Fires" (Italy), a place where waste management has historically been affected by mafia infiltration. Our research is based on a multi-site single case study strategy with qualitative data obtained from semi-structured interviews with several key stakeholders, including public and business managers, civil society leaders, local journalists, local politicians, regional and national politicians, and citizens in their role as co-producers of public services. From a theoretical point of view, our findings contribute to the literature on both place leadership and collaborative governance. From a practical point of view, we shed light on the importance of four interrelated leadership practices to be enacted by public managers and civic leaders to promote positive social change: (a) to recognize and call into existence different publics; (b) to mobilize political leadership; (c) to obtain media salience; and (d) to develop institutional opportunities for enabling agonistic civic capacity.

COVID-19 caused a global pandemic in 2020 that completely revolutionized our way of life, consequently affecting the research area of business, management and accounting sector. The study by Donthu & Gustafsson (2020) had produced some significant elements on the effect of COVID-19 in the considered study area. Since that time, all states and universities have engaged academics in the search for solutions and future prospects related to COVID-19. In 2020 alone, 48,038 results can be identified on Scopus, of which however only 155 related to the sector under investigation. This research seeks to fill the gap by performing a bibliometric review of 155 business, management and accounting articles considering the effects of COVID-19. The study shows that the effect influenced all research areas of the sector, although only some present bilometric evidence with a global diffusion. Bibliometric analysis confirms the trend and studies introduced by Donthu & Gustafsson (2020). The main studies focus on transport, regulation, and the global economy's effect, considering both international trade and the redefinition of a series of services, including education. The changes in tourism, medical tourism, the business model in food administration, and new technologies related to teaching activities require more in-depth analysis and a major sharing of results.

We report on simultaneous radio and X-ray observations of the radio-emitting magnetar 1E1547.0-5408 on 2009 January 25 and February 3, with the 64-m Parkes radio telescope and the Chandra and XMM-Newton X-ray observatories. The magnetar was observed in a period of intense X-ray bursting activity and enhanced X-ray emission. We report here on the detection of two radio bursts from 1E1547.0-5408, reminiscent of Fast Radio Bursts (FRBs). One of the radio bursts was anticipated by ~1s (about half a rotation period of the pulsar) by a bright SGR-like X-ray burst, resulting in a F_radio/F_X ~ 10^-9. Radio pulsations were not detected during the observation showing the FRB-like radio bursts, while they were detected in the previous radio observation. We also found that the two radio bursts are neither aligned with the latter radio pulsations nor with the peak of the X-ray pulse profile (phase shift of ~0.2). Comparing the luminosity of these FRB-like bursts and those reported from SGR1935+2154, we find that the wide range in radio efficiency and/or luminosity of magnetar bursts in the Galaxy may bridge the gap between "ordinary" pulsar radio bursts and the extragalactic FRB phenomenon., Accepted for publication in ApJ. 9 pages, 3 figures

We currently know about 30 magnetars: seemingly isolated neutron stars whose properties can be (in part) comprehended only acknowledging that they are endowed with magnetic fields of complex morphology and exceptional intensity—at least in some components of the field structure. Although magnetars represent only a small percentage of the known isolated neutron stars, there are almost certainly many more of them, since most magnetars were discovered in transitory phases called outbursts, during which they are particularly noticeable. In outburst, in fact, a magnetar can be brighter in X-rays by orders of magnitude and usually emit powerful bursts of hard-X/soft-gamma-ray photons that can be detected almost everywhere in the Galaxy with all-sky monitors such as those on board the Fermi satellite or the Neil Gehrels Swift Observatory. Magnetars command great attention because the large progress that has been made in their understanding is proving fundamental to fathom the whole population of isolated neutron stars, and because, due to their extreme properties, they are relevant for a vast range of different astrophysical topics, from the study of gamma-ray bursts and superluminous supernovae, to ultraluminous X-ray sources, fast radio bursts, and even to sources of gravitational waves. Several excellent reviews with different focuses were published on magnetars in the last few years: among others, Israel and Dall’Osso, Bursts and flares from highly magnetic pulsars, in Proceedings of the First Session of the Sant Cugat Forum on Astrophysics High-Energy Emission from Pulsars and Their Systems, ed. by D.F. Torres, N. Rea. Astrophysics and Space Science Proceedings (Springer, Heidelberg, 2011), pp. 279–298, Rea and Esposito, Magnetar outbursts: an observational review, in High-Energy Emission from Pulsars and Their Systems. Proceedings of the First Session of the Sant Cugat Forum on Astrophysics, ed. by D.F. Torres, N. Rea. Astrophysics and Space Science Proceedings (Springer, Heidelberg, 2011), pp. 247–273, Turolla and Esposito Int J Mod Phys D 22:1330024-163, 2013, Mereghetti, et al. Space Sci Rev 191:315–338, 2015, Turolla et al., 78:116901, 2015; Kaspi and Beloborodov Annu Rev Astron Astrophys 55:261–301, 2017. Here, we quickly recall the history of these sources and travel through the main observational facts, trying to touch some recent and sometimes little-discussed ramifications of magnetars.