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Aims. The Fornax dwarf spheroidal galaxy (dSph) represents a challenge for some globular cluster (GC) formation models, because an exceptionally high fraction of its stellar mass is locked in its GC system. In order to shed light on our understanding of GC formation, we aim to constrain the amount of stellar mass that Fornax has lost via tidal interaction with the Milky Way (MW). Methods. Exploiting the flexibility of effective multi-component N-body simulations and relying on state-of-the-art estimates of Fornax's orbital parameters, we study the evolution of the mass distribution of the Fornax dSph in observationally justified orbits in the gravitational potential of the MW over 12 Gyr. Results. We find that, though the dark-matter mass loss can be substantial, the fraction of stellar mass lost by Fornax to the MW is always negligible, even in the most eccentric orbit considered. Conclusions. We conclude that stellar-mass loss due to tidal stripping is not a plausible explanation for the unexpectedly high stellar mass of the GC system of the Fornax dSph and we discuss quantitatively the implications for GC formation scenarios. [ABSTRACT FROM AUTHOR]

Aims. Recent observational studies suggest that feedback from active galactic nuclei (AGNs) may play an important role in the formation and evolution of dwarf galaxies, an issue that has received little attention from a theoretical perspective. Methods. We investigated this using two sets of 12 cosmological magnetohydrodynamic simulations of the formation of dwarf galaxies (108.3M⊙ ≤ M* ≤ 109.8M⊙): 10 8.3 M ⊙ ≤ M ⋆ ≤ 10 9.8 M ⊙ one set using a version of the AURIGA galaxy formation physics model including AGN feedback and a parallel set with AGN feedback turned off. Results. We show that the full-physics AGN runs satisfactorily reproduce several scaling relations, including the black-hole-to-stellar mass (MBH-M⋆), the black-hole-to-sigma (MBH-σ⋆), and the baryonic Tully-Fisher relation. We find that the global star formation (SF) of galaxies run with an AGN is reduced compared to the one in which the AGN has been turned off, suggesting that AGN feedback is a viable way of suppressing SF in dwarf galaxies, even though none of our galaxies is completely quenched by z = 0. Furthermore, we find a tight correlation between the median SF rates and the MBH/M⋆ ratio in our simulated dwarfs. Star formation is suppressed due to gas heating in the vicinity of the AGN: less HI gas is available in AGN runs, though the total amount of gas is preserved across the two settings within each galaxy. This indicates that the main effect of AGN feedback in our dwarfs is to heat up and push the gas away from the galaxy's centre rather than expelling it completely. Finally, we show that the two galaxies harbouring the largest supermassive black holes have suffered a considerable (up to ∼65%) reduction in their central dark matter density, pinpointing the role of AGNs in determining the final dark matter mass distribution within dwarf galaxies. This pilot paper highlights the importance of modelling AGN feedback at the lowest mass scales and the impact this can have on dwarf galaxy evolution. [ABSTRACT FROM AUTHOR]

Objective: Rare disease. Background: The columella has many fundamental functions, such as nasal breathing and support of the nasal tip, in addition to the aesthetic role it plays. The columella is one of the most difficult nasal subunits, both from the point of view of disease control and from that of reconstruction. Lesions involving the columella can be difficult to control, and malignancies can spread to the septum, subcutaneous tissues of the lip, and floor of the nasal cavities. Many columella reconstruction methods after resection have been proposed (local nasal flaps, skin grafts, regional flaps, free flaps), depending on the size of the defect, patient's features, surgeon's experience, and patient's aesthetic wishes. Case Report: We present a case of an 82-year-old woman with various comorbidities who had squamous cell carcinoma (G2) originating from the skin of the right side of the columella. The lesion infiltrated the cartilage, arriving to the skin of the columella on the left side and extending to the mucosa of the nasal septum bilaterally. Reconstruction was conducted using a bilateral nasolabial flap, with good functional and aesthetic result. Surgical revision for the autonomization of pedicled flaps was not necessary, nor desired by the patient. Conclusions: The bilateral nasolabial flap is an effective and safe solution for reconstructing the columella, with good support of the tip even without cartilaginous graft. This technique is especially feasible in elderly patients and those with concomitant pathologies, who benefit from rapid healing of the wound. [ABSTRACT FROM AUTHOR]

Aims. We extend the classical formulation of the dynamical friction effect on a test star by Chandrasekhar to the case of relativistic velocities and velocity distributions, also accounting for post-Newtonian corrections to the gravitational force. Methods. The original kinetic framework was revised and used to construct a special-relativistic dynamical friction formula where the relative velocity changes in subsequent encounters are added up with Lorentz transformation, and the velocity distribution of the field stars accounts for relativistic velocities. Furthermore, a simple expression is obtained for systems where the post-Newtonian correction on the gravitational forces become relevant even at non-relativistic particle velocities. Finally, using a linearized Lagrangian we derived another expression for the dynamical friction expression in a more compact form than previously used. Results. Comparing our formulation with the classical one, we observe that a given test particle undergoes a slightly stronger drag when moving through a distribution of field stars with relativistic velocity distribution. Vice versa, a purely classical treatment of a system where post-Newtonian (PN) corrections should be included, overestimates the effect of dynamical friction at low test particle velocity, regardless of the form of velocity distribution. Finally, a first-order PN dynamical friction covariant formulation is weaker its classical counterpart at small velocities, but much higher for large velocities over a broad range of mass ratios. [ABSTRACT FROM AUTHOR]

Background: The treatment of the primary tumour in colorectal cancer with unresectable liver and/or lung metastases but no peritoneal carcinomatosis is still a matter of debate. In the absence of clear evidence and guidelines, our survey was aimed at obtaining a snapshot of the current attitudes and the rationales for the choice of offering resection of the primary tumour (RPT) despite the presence of untreatable metastases. Methods: An online survey was administered to medical professionals worldwide. The survey had three sections: (1) demographics of the respondent, (2) case scenarios and (3) general questions. For each respondent, an "elective resection score" and an "emergency resection score" were calculated as a percentage of the times he or she would offer RPT in the elective and in the emergency case scenarios. They were correlated to independent variables such as age, type of affiliation and specific workload. Results: Most respondents would offer palliative chemotherapy as the first choice in elective scenarios, while a more aggressive approach with RPT would be reserved for younger patients with good performance status and in emergency situations. Respondents younger than 50 years old and those with a specific workload of fewer than 40 cases of colorectal cancer per year tend to be more conservative. Conclusions: In the absence of clear guidelines and evidence, there is a lack of consensus on the treatment of the primary tumour in case of colon cancer with unresectable liver and/or lung metastases and no peritoneal carcinomatosis. Palliative chemotherapy seems to be the first option, but more consistent evidence is needed to guide this choice. [ABSTRACT FROM AUTHOR]

Supernovae feedback driven expansion has proven to be a viable mechanism to explain the average properties, such as size, colour, mass, and internal kinematics, of a large fraction of ultradiffuse galaxies (UDGs). Here, we explore the origin of stellar metallicity gradients in feedback driven simulated UDGs from the NIHAO project and compare them with the observed distribution of metallicity gradients of both Local Group (LG) dwarfs as well as of the recently observed UDG DF44. Simulated UDGs display a large variety of metallicity profiles, showing flat to negative gradients, similarly to what is observed in LG dwarfs, while DF44 data suggest a flat to positive gradient. The variety of metallicity gradients in simulations is set by the interplay between the radius at which star formation occurs and the subsequent supernovae feedback driven stellar redistribution: rotation supported systems tend to have flat metallicity profiles while dispersion supported galaxies show negative and steep profiles. Our results suggest that UDGs are not peculiar in what regards their metallicity gradients, when compared to regular dwarfs. We predict that UDGs formed via SNae feedback should have flat-to-negative metallicity profiles: desirably, a larger observational sample of UDGs' gradients shall be available in the future, in order to test our predictions. [ABSTRACT FROM AUTHOR]

We investigate the evolution of the phase–space distribution function around slightly perturbed stationary states and the process of violent relaxation in the context of the dissipationless collapse of an isolated spherical self-gravitating system. By means of the recently introduced symplectic coarse graining technique, we obtain an effective evolution equation that allows us to compute the scaling of the frequencies around a stationary state, as well as the damping times of Fourier modes of the distribution function, with the magnitude of the Fourier k −vectors themselves. We compare our analytical results with N -body simulations. [ABSTRACT FROM AUTHOR]

By means of numerical simulations we study the radial-orbit instability in anisotropic self-gravitating N–body systems under the effect of noise. We find that the presence of additive or multiplicative noise has a different effect on the onset of the instability, depending on the initial value of the orbital anisotropy. [ABSTRACT FROM AUTHOR]

Local Group satellite galaxies show a wide diversity of star formation histories (SFHs) whose origin is yet to be fully understood. Using hydrodynamical simulations from the Constrained Local UniversE project, we study the SFHs of satellites of Milky Way-like galaxies in a cosmological context: while in the majority of the cases the accretion on to their host galaxy causes the satellites to lose their gas, with a subsequent suppression in SF, in about 25 per cent of our sample we observe a clear enhancement of SF after infall. Peaks in SF clearly correlate with the satellite pericentric passage around its host and, in one case, with a satellite–satellite interaction. We identify two key ingredients that result in enhanced SF after infall: galaxies must enter the host's virial radius with a reservoir of cold gas M gas, inf/ M vir, inf ≳ 10−2 and with a minimum pericentric distance ≳10 kpc (mean distance ∼50 kpc for the full sample), in order to form new stars due to compression of cold gas at pericentric passage. On the other hand, satellites that infall with little gas or whose pericentric distance is too small, have their gas ram-pressure stripped and subsequent SF quenched. The pericentric passage of satellites likewise correlates with SF peaks in their hosts, suggesting that this mechanism induces bursts of SF in satellites and central galaxies alike, in agreement with recent studies of our Galaxy's SFH. Our findings can explain the recently reported multiple stellar populations observed in dwarf galaxies such as Carina and Fornax, and should be taken into account in semi-analytic models of galaxy formation and satellite quenching. [ABSTRACT FROM AUTHOR]

Purpose: Parastomal recurrence of squamous cell carcinoma (SCC) with tracheal involvement following salvage total laryngectomy after prior concurrent chemoradiotherapy is one of the most insidious challenges in head and neck surgery because a complex reconstruction is often required for covering a large area of skin loss, filling the dead space beneath, tracheal reconstruction and suspension, and tracheostome resurfacing. The aim is to describe our experience with the internal mammary artery perforator (IMAP) propeller flap for tracheal and tracheostome reconstruction and neck resurfacing after parastomal and cervical trachea resection, especially for suspension and anchoring the stump of the residual distal trachea to the island flap itself. Methods: We describe IMAP flap reconstruction after resection of parastomal recurrence of SCC requiring cervical trachea resection in five patients between January 1, 2005 and August 30, 2019. Results: IMAP propeller flap was successfully used for reconstruction after complex resection of parastomal recurrence of SCC with cervical trachea involvement in all cases. The mean length and width were, respectively, 16.8 cm (range 13–23) and 6.9 cm (range 5.5–8). We did not report complications of both the donor and the recipient site. Pharyngo-cutaneous or tracheoesophageal fistulas and wound dehiscence were not observed. Conclusions: to the best of our knowledge, this is the first report about the use of the IMAP propeller flap in this more complex clinical setting and we provide the message that this surgical procedure is worthy of consideration. [ABSTRACT FROM AUTHOR]

In recent years, a new window on galaxy evolution opened, thanks to the increasing discovery of galaxies with a low-surface brightness, such as Ultra Diffuse Galaxies (UDGs). The formation mechanism of these systems is still a much debated question and so are their kinematical properties. In this work, we address this topic by analysing the stellar kinematics of isolated UDGs formed in the hydrodynamical simulation suite Numerical Investigation of a Hundred Astrophysical Objects (NIHAO). We construct projected line-of-sight velocity and velocity dispersion maps to compute the projected specific angular momentum, λR, to characterize the kinematical support of the stars in these galaxies. We found that UDGs cover a broad distribution, ranging from dispersion to rotation-supported galaxies, with similar abundances in both regimes. The degree of rotation support of simulated UDGs correlates with several properties such as galaxy morphology, higher H  i fractions, and larger effective radii with respect to the dispersion-supported group, while the dark matter halo spin and mass accretion history are similar among the two populations. We demonstrate that the alignment of the infalling baryons into the protogalaxy at early z is the principal driver of the z  = 0 stellar kinematic state: pressure-supported isolated UDGs form via misaligned gas accretion while rotation-supported ones build up their baryons in an ordered manner. Accounting for random inclination effects, we predict that a comprehensive survey will find nearly half of field UDGs to have rotationally supported stellar discs, when selecting UDGs with effective radius larger than 1 kpc. [ABSTRACT FROM AUTHOR]

We use Gaia DR2 systemic proper motions of 45 satellite galaxies to constrain the mass of the Milky Way using the scale-free mass estimator of Watkins et al. (2010). We first determine the anisotropy parameter β , and the tracer satellites' radial density index γ to be β  = |$-0.67^{+0.45}_{-0.62}$| and γ = 2.11 ± 0.23. When we exclude possible former satellites of the Large Magellanic Cloud, the anisotropy changes to β  = |$-0.21^{+0.37}_{-0.51}$|⁠. We find that the index of the Milky Way's gravitational potential α , which is dependent on the mass itself, is the parameter with the largest impact on the mass determination. Via comparison with cosmological simulations of Milky Way-like galaxies, we carried out a detailed analysis of the estimation of the observational uncertainties and their impact on the mass estimator. We found that the mass estimator is biased when applied naively to the satellites of simulated Milky Way haloes. Correcting for this bias, we obtain for our Galaxy a mass of |$0.58^{+0.15}_{-0.14}\times 10^{12}$|  M⊙ within 64 kpc, as computed from the inner half of our observational sample, and |$1.43^{+0.35}_{-0.32}\times 10^{12}$|  M⊙ within 273 kpc, from the full sample; this latter value extrapolates to a virial mass of |$M_\mathrm{vir\, \Delta =97}=1.51^{+0.45}_{-0.40} \times 10^{12}\,{\rm M}_{\odot }$| corresponding to a virial radius of R vir = 308 ± 29 kpc. This value of the Milky Way mass lies in-between other mass estimates reported in the literature, from various different methods. [ABSTRACT FROM AUTHOR]

We study the stability of a family of spherical equilibrium models of self-gravitating systems, the so-called γ models with Osipkov–Merritt velocity anisotropy, by means of N -body simulations. In particular, we analyse the effect of self-consistent N -body chaos on the onset of radial-orbit instability. We find that degree of chaoticity of the system associated with its largest Lyapunov exponent Λmax has no appreciable relation with the stability of the model for fixed density profile and different values of radial velocity anisotropy. However, by studying the distribution of the Lyapunov exponents λm of the individual particles in the single-particle phase space, we find that more anisotropic systems have a larger fraction of orbits with larger λm. [ABSTRACT FROM AUTHOR]

We revisit the role of discreteness and chaos in the dynamics of self-gravitating systems by means of N -body simulations with active and frozen potentials, starting from spherically symmetric stationary states and considering the orbits of single particles in a frozen N -body potential as well as the orbits of the system in the full 6 N -dimensional phase space. We also consider the intermediate case where a test particle moves in the field generated by N non-interacting particles, which in turn move in a static smooth potential. We investigate the dependence on N and on the softening length of the largest Lyapunov exponent both of single particle orbits and of the full N -body system. For single orbits, we also study the dependence on the angular momentum and on the energy. Our results confirm the expectation that orbital properties of single orbits in finite N systems approach those of orbits in smooth potentials in the continuum limit N → ∞ and that the largest Lyapunov exponent of the full N -body system does decrease with N , for sufficiently large systems with finite softening length. However, single orbits in frozen models and active self-consistent models have different largest Lyapunov exponents and the N -dependence of the values in non-trivial, so that the use of frozen N -body potentials to gain information on large N systems or on the continuum limit may be misleading in certain cases. [ABSTRACT FROM AUTHOR]

The existence of galaxies with a surface brightness μ lower than the night sky has been known since three decades. Yet, their formation mechanism and emergence within a Lambda cold dark matter universe has remained largely undetermined. For the first time, we investigated the origin of low surface brightness (LSB) galaxies with M ⋆ ∼ 109.5−10 M⊙, which we are able to reproduce within hydrodynamical cosmological simulations from the NIHAO suite. The simulated and observed LSB galaxies share similar properties, having large H  i reservoir, extended star formation histories and effective radii, low Sérsic index, and slowly rising rotation curves. The formation mechanism of these objects is explored: simulated LSB galaxies form as a result of coplanar co-rotating mergers and aligned accretion of gas at early times, while perpendicular mergers and misaligned gas accretion result in higher μ galaxies by z  = 0. The larger the merger, the stronger the correlation between merger orbital configuration and final μ. While the halo spin parameter is consistently high in simulated LSB galaxies, the impact of halo concentration, feedback-driven gas outflows, and merger time only plays a minor-to-no role in determining μ. Interestingly, the formation scenario of such 'classical' LSB galaxies differs from the one of less massive, M ⋆ ∼ 107–9 M⊙, ultra-diffuse galaxies, the latter resulting from the effects of SNae-driven gas outflows: an M ⋆ of ∼109 M⊙ thus represents the transition regime between a feedback-dominated to an angular-momentum-dominated formation scenario in the LSB realm. Observational predictions are offered regarding spatially resolved star formation rates through LSB discs: these, together with upcoming surveys, can be used to verify the proposed emergence scenario of LSB galaxies. [ABSTRACT FROM AUTHOR]

HST /ACS observations along the major axis of M33 show that the mean age of its stars decreases with increasing distance from the galaxy centre. Such a behaviour is consistent with an inside-out growth of the disc. However, in the outermost observed field, at r ≃ 11.6 kpc, a reversal of this gradient is detected, with old stars found in high percentages beyond this radius. In this work, we investigate the origin of such a reversal in stellar age gradient, by using a simulated M33 analogue from the Constrained Local UniversE Simulations (CLUES). The simulated M33 is similar to the observed one in terms of mass, rotation velocity, surface brightness, and, similar to what has been reported in observations, shows a stellar age turnaround at large radii. We demonstrate that this reversal is mostly a result of stellar accretion from old satellite galaxies and, to a lesser extent, of stellar migration of in-situ stars. The old accreted stars, with formation times tf < 4 Gyrs, are kinematically hot and can be differentiated from the in-situ stars by their high velocity dispersion and the fact that they do not have rotationally supported orbits. In the future, obtaining kinematic information of the stars in the outskirt of M33 will help to verify this scenario. [ABSTRACT FROM AUTHOR]

We continue to investigate the dynamics of collisionless systems of particles interacting via additive r-α interparticle forces. Here we focus on the dependence of the radial-orbit instability on the force exponent α. By means of direct N-body simulations, we study the stability of equilibrium radially anisotropic Osipkov--Merritt spherical models with Hernquist density profile and with 1 ≤ α < 3. We determine, as a function of α, the minimum value for stability of the anisotropy radius ras and of the maximum value of the associated stability indicator ξs. We find that for decreasing α, ras decreases and ξs increases, i.e. longer range forces are more robust against radial-orbit instability. The isotropic systems are found to be stable for all the explored values of α. The end products of unstable systems are all markedly triaxial with minor-to-major axial ratio >0.3, so they are never flatter than an E7 system. [ABSTRACT FROM AUTHOR]

Don Antonio Londonio (1532-1592) was born in Castile and settled in Milan in the late 1550s. He was both a prominent politician and one of the main patrons of the arts in Lombardy: musicians, poets, philosophers, and other artists in Northwest Italy benefited from his protection. Maddalena Casulana, Pietro Vinci, and Marc'Antonio Ingegneri dedicated madrigal books to him between 1570 and 1584. These dedications, together with other documents (notarial acts, collections of poems and letters, the proceedings of the trial in which Londonio was involved from 1581 onwards), make it possible for us to identify the members of his artistic circle. In general, they convey the image of a patron who ' given his considerable musical competence ' must have played a significant role in the preparation of the music books dedicated to him. In particular, the encomiastic madrigals and the texts on political matters can be considered as expressions of Londonio's ideas, the institutional tasks that he had to carry out in the Duchy of Milan and the relationships he was able to develop with musical circles in Lombardy.Antonio Londonio also had a significant role in the editing of Paolo Caracciolo's Primo libro de' madrigali a cinque voci (Venice, Scotto, 1582). More generally, this anthology indirectly sheds light on Milanese musical life in the late 1500s, which was animated by individuals ' mainly from the lower aristocracy or officials of the imperial court ' who in turn patronized the publication of musical works and probably promoted the circulation of books of poetry and madrigals produced in Milan both in Central and Northern Italy and in Central Europe. [ABSTRACT FROM AUTHOR]

We address the origin of ultra-diffuse galaxies (UDGs), which have stellar masses typical of dwarf galaxies but effective radii of Milky Way-sized objects. Their formation mechanism, and whether they are failed L⋆ galaxies or diffuse dwarfs, are challenging issues. Using zoom-in cosmological simulations from the Numerical Investigation of a Hundred Astrophysical Objects (NIHAO) project, we show that UDG analogues form naturally in dwarf-sized haloes due to episodes of gas outflows associated with star formation. The simulated UDGs live in isolated haloes of masses 1010–11 M⊙, have stellar masses of 107–8.5 M⊙, effective radii larger than 1 kpc and dark matter cores. They show a broad range of colours, an average Sérsic index of 0.83, a typical distribution of halo spin and concentration, and a non-negligible H i gas mass of 107 − 9 M⊙, which correlates with the extent of the galaxy. Gas availability is crucial to the internal processes which form UDGs: feedback-driven gas outflows, and subsequent dark matter and stellar expansion, are the key to reproduce faint, yet unusually extended, galaxies. This scenario implies that UDGs represent a dwarf population of low surface brightness galaxies and should exist in the field. The largest isolated UDGs should contain more H i gas than less extended dwarfs of similar M⋆. [ABSTRACT FROM AUTHOR]

This work explores the mixing rate of metals in the interstellar medium (ISM), comparing observational constraints from our solar neighbourhood to high resolution cosmological hydrodynamical simulations of Milky Way (MW)-like galaxies. The mixing rate, described by the coefficient C, is varied in simulations between 0 and 0.05, with resultant simulated galaxies compared to observations of metallicity dispersion in young star clusters, H ii regions and neutral gas in the disc of the MW. A value of C between 0.003125 and 0.0125 is found to self-consistently match a range of observables, with a best estimate of C = 0.0064 ± 0.0004. We demonstrate that the relationship between metal dispersion in young stars, H ii regions and neutral gas, versus the coefficient C, can be described by a power law. These constrained mixing rates infer a comparatively well-mixed ISM in the solar neighbourhood, at odds with some recent observations that have reported a highly inhomogeneous ISM. The degree of mixing suggested by this work is lower than what often employed in many hydrodynamical simulations. Our results have implications for studying the metallicity distribution of stars as well as of gas in the interstellar and circum-galactic media. [ABSTRACT FROM AUTHOR]

We study the anomalous dynamical scaling of equilibrium correlations in one-dimensional systems. Two different models are compared: the Fermi-Pasta-Ulam chain with cubic and quartic nonlinearity and a gas of point particles interacting stochastically through multiparticle collision dynamics. For both models--that admit three conservation laws--by means of detailed numerical simulations we verify the predictions of nonlinear fluctuating hydrodynamics for the structure factors of density and energy fluctuations at equilibrium. Despite this, violations of the expected scaling in the currents correlation are found in some regimes, hindering the observation of the asymptotic scaling predicted by the theory. In the case of the gas model this crossover is clearly demonstrated upon changing the coupling constant. [ABSTRACT FROM AUTHOR]

Dark matter cores within galaxy haloes can be formed by energy feedback from star-forming regions: an energy balance suggests that the maximum core formation efficiency arises in galaxies with Mstar ~ 108.5M⊙. We show that a model population of galaxies, in which the density profile has been modified by such baryonic feedback, is able to explain the observed galaxy velocity function and Tully-CFisher relations significantly better than a model in which a universal cuspy density profile is assumed. Alternative models, namely warm or self-interacting dark matter, also provide a better match to these observed relations than a universal profile model does, but make different predictions for how halo density profiles vary with mass compared to the baryonic feedback case. We propose that different core formation mechanisms may be distinguished based on the imprint they leave on galaxy populations over a wide range of mass. Within the current observational data we find evidence of the expected signatures of the mass dependence of core formation generated by baryonic feedback. [ABSTRACT FROM AUTHOR]

Observed kinematical data of 40 Local Group (LG) members are used to derive the dark matter halo mass of such galaxies. Haloes are selected from the theoretically expected LG mass function and two different density profiles are assumed, a standard universal cuspy model and a mass-dependent profile which accounts for the effects of baryons in modifying the dark matter distribution within galaxies. The resulting relations between stellar and halo mass are compared with expectations from abundance matching. Using a universal cuspy profile, the ensemble of LG galaxies is fit in relatively low-mass haloes, leaving 'dark' many massive haloes of Mhalo ≳ 1010 M⊙: this reflects the 'too-big-to-fail' problem and results in a Mstar-Mhalo relation that differs from abundance matching predictions. Moreover, the star formation efficiency of isolated LG galaxies increases with decreasing halo mass when adopting a cuspy model. By contrast, using the mass-dependent density profile, dwarf galaxies with Mstar ≳ 106 M⊙ are assigned to more massive haloes, which have a central cored distribution of dark matter: the 'too-big-to-fail' problem is alleviated, the resultant Mstar-Mhalo relation follows abundance matching predictions down to the completeness limit of current surveys, and the star formation efficiency of isolated members decreases with decreasing halo mass, in agreement with theoretical expectations. Finally, the cusp/core space of LG galaxies is presented, providing a framework to understand the non-universality of their density profiles. [ABSTRACT FROM AUTHOR]

Small-scale fisheries in Italy account for around 70% of the total fishing fleet, as well as nearly 30% and 55% of capture-fisheries revenues and employment, respectively. Yet, the sector is experiencing a deep crisis, mostly due to reduced catches and to the consequent decrease in revenues. At the same time, a lack of socio-economic data is hampering an effective resource management and the identification of adequate market solutions to improve fishers' livelihoods. To address the issue, a survey has been carried out on the value chain's structure and functioning of small-scale fishery fleets operating inside three marine protected areas in southern Italy. The assessment was performed following an interview-based approach through questionnaires administered to different categories of stakeholders. Results show that small-scale fishers receive the least economic benefits from their catches, while wholesalers and fish shops achieve the highest sale price thanks to their stronger bargaining power. Particularly, the highest mark-ups occur for those product shops that have little or no interest invested in them (i.e., those for which the fishers are paid less). Finally, this paper discusses a few potential market solutions to address the major threats to fisher livelihoods, such as direct sale or transformation of the catch. The latter option should especially be targeted to low value fish, which is often disregarded by shops, but which could generate higher incomes for fishers through the adoption of appropriate marketing strategies. [ABSTRACT FROM AUTHOR]

Clusters consisting of small molecules containing hydrogen do eject fast protons when illuminated by short x-ray pulses. A suitable overall charging of the cluster controlled by the x-ray intensity induces electron migration from the surface to the bulk leading to efficient segregation of the protons and to a globally hindered explosion of the heavy atoms even outside the screened volume. We investigate this peculiar effect systematically along the isoelectronic sequence of methane over ammonia and water to the atomic limit of neon as a reference. In contrast to core-shell systems where the outer shell is sacrificed to reduce radiation damage, the intricate proton dynamics of hydride clusters allows one to keep the entire backbone of heavy atoms intact. [ABSTRACT FROM AUTHOR]

In Newtonian gravity the final states of cold dissipationless collapses are characterized by several structural and dynamical properties remarkably similar to those of observed elliptical galaxies. Are these properties a peculiarity of the Newtonian force or a more general feature of long-range forces? We study this problem by means of N-body simulations of dissipationless collapse of systems of particles interacting via additive r−α forces. We find that most of the results holding in Newtonian gravity are also valid for α ≠ 2. In particular, the end-products are triaxial and never flatter than an E7 system, their surface density profiles are well described by the Sérsic law, the global density slope–anisotropy inequality is obeyed, the differential energy distribution is an exponential over a large range of energies (for α ≥ 1), and the pseudo-phase-space density is a power law of radius. In addition, we show that the process of virialization takes longer (in units of the system's dynamical time) for decreasing values of α, and becomes infinite for α = −1 (the harmonic oscillator). This is in agreement with the results of deep Modified Newtonian Dynamics collapses (qualitatively corresponding to α = 1) and it is due to the fact that the force becomes more and more similar to the α = −1 case, where, as well known, no relaxation can happen and the system oscillates forever. [ABSTRACT FROM AUTHOR]

We use dark matter only and full hydrodynamical Constrained Local Universe Simulations of the formation of the Local Group to study the density profile of subhaloes of the simulated Milky Way and Andromeda galaxies. We show that the Einasto model provides the best description of the subhaloes’ density profile, as opposed to the more commonly used Navarro, Frenk & White profile or any generalization of it. We further find that the Einasto shape parameter nE is strongly correlated with the total subhalo mass, pointing towards the notion of a non-universality of the subhaloes’ density profile. We observe that the effect of mass-loss due to tidal stripping, in both the dark matter only and the hydrodynamical run, is the reduction of the shape parameter nE between the infall and the present time. Assuming now that the dwarf spheroidals (dSphs) of our Galaxy follow the Einasto profile and using the maximum and minimum values of nE from our hydrodynamical simulation as a gauge, we can improve the observational constraints on the Rmax–Vmax pairs obtained for the brightest satellite galaxies of the Milky Way. When considering only the subhaloes with −13.2 ≲ MV ≲ −8.8, i.e. the range of luminosity of the classical dwarfs, we find that all our simulated objects are consistent with the observed dSphs if their haloes follow the Einasto model with 1.6 ≲ nE ≲ 5.3. The numerically motivated Einasto profile for the observed dSphs will alleviate the recently presented ‘massive failures’ problem. [ABSTRACT FROM AUTHOR]

In this paper, we estimate wage gains due to geographic mobility of Italian university graduates three years after graduation. By means of a matching procedure we quantify wage premia associated with the choice of studying far from home, moving after graduation and moving back home after graduation. We find evidence of large heterogeneity in the returns to different migration patterns. The results show large gains for those who move after graduation and smaller gains for those who migrate to study. Conversely, those who choose to go back home after having studied in regions different from that of origin suffer small losses. Our findings are robust to a finer definition of mobility and to the subsample of individuals originating from the South. [ABSTRACT FROM AUTHOR]

ABSTRACT We use the recently proposed scale-free mass estimators to determine the masses of the Milky Way (MW) and Andromeda (M31) galaxy in a dark matter only Constrained Local Universe Simulation. While these mass estimators work rather well for isolated spherical host systems, we examine here their applicability to a simulated binary system with a unique satellite population similar to the observed satellites of MW and M31. We confirm that the scale-free estimators work also very well in our simulated Local Group galaxies with the right number of satellites which follow the observed radial distribution. In the isotropic case and under the assumption that the satellites are tracking the total gravitating mass, the power-law index of the radial satellite distribution N(< r) ∝ r3−γ is directly related to the host's mass profile M(< r) ∝ r1−α as α=γ− 2. The use of this relation for any given γ leads to highly accurate mass estimations which is a crucial point for observer, since they do not know a priori the mass profile of the MW and M31 haloes. We discuss possible bias in the mass estimators and conclude that the scale-free mass estimators can be satisfactorily applied to the real MW and M31 system. [ABSTRACT FROM AUTHOR]

A personnel narrative is presented which explores the author's experience of returning to Tohono O'odham Indian Reservation in Arizona, focusing on the traditional foods of the region.

ABSTRACT Using Constrained Local UniversE Simulations (CLUES) of the formation of the Local Group in a cosmological context, we investigate the recently highlighted problem that the majority of the most massive dark subhaloes of the Milky Way (MW) are too dense to host any of its bright satellites. In particular, we examine the influence of baryonic processes and find that they leave a twofold effect on the relation between the peak of the rotation curve and its position ( Vmax and Rmax). Satellites with a large baryon fraction experience adiabatic contraction, thus decreasing Rmax while leaving Vmax more or less unchanged. Subhaloes with smaller baryon fractions undergo a decrease in Vmax possibly due to outflows of material. Furthermore, the situation of finding subhaloes in simulations that lie outside the confidence interval for possible hosts of the bright MW dwarf spheroidals appears to be far more prominent in cosmologies with a high σ8 normalization and depends on the mass of the host. We conclude that the problem cannot be simply solved by including baryonic processes and hence demands further investigations. [ABSTRACT FROM AUTHOR]

The process of relaxation of a system of particles interacting with long-range forces is relevant to many areas of physics. For obvious reasons, in Stellar Dynamics much attention has been paid to the case of r-2 force law. However, recently the interest in alternative gravities has emerged, and significant differences with respect to Newtonian gravity have been found in relaxation phenomena. Here we begin to explore this matter further, by using a numerical model of spherical shells interacting with an r-α force law obeying the superposition principle. We find that the virialization and phase-mixing times depend on the exponent α, with small values of α corresponding to longer relaxation times, similarly to what happens when comparing for N-body simulations in classical gravity and in Modified Newtonian Dynamics. [ABSTRACT FROM AUTHOR]

The role of elective neck dissection during salvage surgery in patients with a clinically negative neck (cN0) is still discussed. The main objective of this work was to estimate the prevalence and predictive factors of occult neck nodes metastasis; we therefore aimed to evaluate the survival rate and the main oncologic outcomes of cN0 patients who underwent salvage total laryngectomy and elective bilateral neck dissection. In this retrospective observational study, we enrolled 80 cN0 patients affected by recurrent laryngeal cancer and who underwent salvage total laryngectomy and bilateral selective elective neck dissection. Several parameters were collected in order to find prognostic factors; finally, postoperative complications were reviewed and survival analysis was performed. Occult lymph node metastases were reported in 18 out of 80 patients (22.5%). Significant statistical correlation between lymphovascular invasion (p = 0.007), perineural invasion (p = 0.025) and occult nodal metastasis was found. Other variables (glottic subsite of recurrence, clinical T, pathological T, previous chemotherapy) were not significantly predictive of occult nodal metastasis. The 5-year OS, DSS, and RFS were 50.4%, 64.7%, and 63.4%, respectively. In conclusion, our single-institution data on a large cohort of patients, suggest performing routinely elective selective bilateral neck dissection during salvage total laryngectomy in cN0 patients due to the biological attitude of the tumor to spread to cervical nodes, considering an acceptable complications rate. [ABSTRACT FROM AUTHOR]

Examines the effects of the interaction of working memory span (WMS) while assessing the influence of contextual information. Details on the study done; Design of the study; Methodology used in the study; Results and discussion of the study; Conclusion reached.

Star formation in molecular clouds is clumpy, hierarchically subclustered. Fractal structure also emerges in hydrodynamical simulations of star-forming clouds. Simulating the formation of realistic star clusters with hydrodynamical simulations is a computational challenge, considering that only the statistically averaged results of large batches of simulations are reliable, due to the chaotic nature of the gravitational N -body problem. While large sets of initial conditions for N -body runs can be produced by hydrodynamical simulations of star formation, this is prohibitively expensive in terms of computational time. Here, we address this issue by introducing a new technique for generating many sets of new initial conditions from a given set of star masses, positions, and velocities from a hydrodynamical simulation. We use hierarchical clustering in phase space to inform a tree representation of the spatial and kinematic relations between stars. This constitutes the basis for the random generation of new sets of stars which share the clustering structure of the original ones but have individually different masses, positions, and velocities. We apply this method to the output of a number of hydrodynamical star-formation simulations, comparing the generated initial conditions to the original ones through a series of quantitative tests, including comparing mass and velocity distributions and fractal dimension. Finally, we evolve both the original and the generated star clusters using a direct N -body code, obtaining a qualitatively similar evolution. [ABSTRACT FROM AUTHOR]

We present a numerical study of dynamical correlations (structure factors) of the long-range generalization of the Fermi–Pasta–Ulam oscillator chain, where the strength of the interaction between two lattice sites decays as a power of the inverse of their distance. The structure factors at finite energy density display distinct peaks, corresponding to long-wavelength propagating modes, whose dispersion relation is compatible with the predictions of the linear theory. We demonstrate that dynamical scaling holds, with a dynamical exponent z that depends weakly on in the range . The lineshapes have a non-trivial functional form and appear somehow independent of . Within the accessible time and size ranges, we also find that the short-range limit is hardly attained even for relatively large values of . [ABSTRACT FROM AUTHOR]

Stellar prolate rotation in dwarf galaxies is rather uncommon, with only two known galaxies in the Local Group showing such feature (Phoenix and And II). Cosmological simulations show that in massive early-type galaxies prolate rotation likely arises from major mergers. However, the origin of such kinematics in the dwarf galaxies regime has only been explored using idealized simulations. Here, we made use of hydrodynamical cosmological simulations of dwarfs galaxies with stellar mass between 3 × 105 and 5 × 108  M⊙ to explore the formation of prolate rotators. Out of 27 dwarfs, only one system showed clear rotation around the major axis, whose culprit is a major merger at |$z$| = 1.64, which caused the transition from an oblate to a prolate configuration. Interestingly, this galaxy displays a steep metallicity gradient, reminiscent of the one measured in Phoenix and And II: this is the outcome of the merger event that dynamically heats old, metal-poor stars, and of the centrally concentrated residual star formation. Major mergers in dwarf galaxies offer a viable explanation for the formation of such peculiar systems, characterized by steep metallicity gradients and prolate rotation. [ABSTRACT FROM AUTHOR]

Ophthalmic vein thrombosis is a severe clinical entity with proptosis, eyelid swelling, orbital pain and reduction of visual acuity; its incidence is rare with 3–4 cases /million /year. Clinical manifestations result from venous congestion caused by septic (orbital cellulitis) or aseptic aetiologies (coagulopathies, trauma) and in some cases it could be associated with cavernous sinus thrombosis. In this paper, we describe a case report unique in the literature, of bilateral cavernous sinus and ophthalmic veins thrombosis due to both septic and aseptic causes characterized by unilateral sphenoid sinusitis sustained by Trueperella pyogenes infection. Trueperella pyogenes is an opportunistic animal pathogen, and its infections occur in both domestic and wild animals worldwide but are rare in humans; this is the first instance of human infection in the head and neck with an unknown hypercoagulable state. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the antimicrobial efficacy of an air gas soft jet CAP for its potential use in removing oral biofilms, given that plasma-based technologies have emerged as promising methods in periodontology. Two types of biofilms were developed, one by Streptococcus mutans UA 159 bacterial strain and the other by a complex mixture of saliva microorganisms isolated from a patient with periodontitis. This latter biofilm was characterized via Next Generation Sequencing to determine the main bacterial phyla. The CAP source was applied at a distance of 6 mm for different time points. A statistically significant reduction of both CFU count and XTT was already detected after 60 s of CAP treatment. CLSM analysis supported CAP effectiveness in killing the microorganisms inside the biofilm and in reducing the thickness of the biofilm matrix. Cytotoxicity tests demonstrated the possible use of CAP without important side effects towards human gingival fibroblasts cell line. The current study showed that CAP treatment was able to significantly reduce preformed biofilms developed by both S. mutans and microorganisms isolated by a saliva sample. Further studies should be conducted on biofilms developed by additional saliva donors to support the potential of this innovative strategy to counteract oral pathogens responsible for periodontal diseases. [ABSTRACT FROM AUTHOR]

We investigate thermal conduction in arrays of long-range interacting rotors and Fermi-Pasta-Ulam (FPU) oscillators coupled to two reservoirs at different temperatures. The strength of the interaction between two lattice sites decays as a power α of the inverse of their distance. We point out the necessity of distinguishing between energy flows towards or from the reservoirs and those within the system. We show that energy flow between the reservoirs occurs via a direct transfer induced by long-range couplings and a diffusive process through the chain. To this aim, we introduce a decomposition of the steady-state heat current that explicitly accounts for such direct transfer of energy between the reservoir. For 0≤α<1, the direct transfer term dominates, meaning that the system can be effectively described as a set of oscillators each interacting with the thermal baths. Also, the heat current exchanged with the reservoirs depends on the size of the thermalized regions: In the case in which such size is proportional to the system size N, the stationary current is independent on N. For α>1, heat transport mostly occurs through diffusion along the chain: For the rotors transport is normal, while for FPU the data are compatible with an anomalous diffusion, possibly with an α-dependent characteristic exponent. [ABSTRACT FROM AUTHOR]

Purpose: We aim to propose a new protocol for olfaction rehabilitation after total laryngectomy based on training of sensory perception levels using the Nasal Airflow-Inducing Maneuver. Methods: This is a randomized clinical trial including patients undergoing total laryngectomy between March 2010 and March 2019. Patients with nasal or oral abnormalities, prior olfaction impairment, a muco-ciliary transport time higher than 30 min, positive history for feeding, and neurological disorders were excluded. Thirty-three patients were enrolled and were randomized into two groups: an Experimental group, submitted to the new protocol (olfactory perception rehabilitation after total laryngectomy-OPRAT) and a Control group that did not receive any treatment. Subjective Olfactometry, Chemosensory Complaints Score, and University of Washington Quality of Life version 4 questionnaires were used to assess the outcomes before and after treatment, and at 3-month, 6-month, and 10-month follow-up. Results: Among the 33 patients included (32 men and 1 woman; mean age, 67.94 ± 5.64 years), 17 were subjected to olfaction rehabilitation and 16 did not receive any treatment. At baseline evaluation, there were not significant differences between the two groups. At the end of treatment, the rehabilitated group improved their olfaction capability significantly. Such improvement remained stable over time, and after 10 months, only the Experimental group had significant improvements in all outcome measures. Conclusions: The OPRAT may guarantee excellent results in the short- and long-term time with positive effects on the Quality of Life. [ABSTRACT FROM AUTHOR]

The development of nanostructures for therapeutic purpose is rapidly growing, following the results obtained in vivo in animal models and in the clinical trials. Unfortunately, the potential therapeutic efficacy is not completely exploited, yet. This is mainly due to the fast clearance of the nanostructures in the body. Nanoparticles and the liver have a unique interaction because the liver represents one of the major barriers for drug delivery. This interaction becomes even more relevant and complex when the drug delivery strategies employing nanostructures are proposed for the therapy of liver diseases, such as hepatocellular carcinoma (HCC). In this case, the selective delivery of therapeutic nanoparticles to the tumor microenvironment collides with the tendency of nanostructures to be quickly eliminated by the organ. The design of a new therapeutic approach based on nanoparticles to treat HCC has to particularly take into consideration passive and active mechanisms to avoid or delay liver elimination and to specifically address cancer cells or the cancer microenvironment. This review will analyze the different aspects concerning the dual role of the liver, both as an organ carrying out a clearance activity for the nanostructures and as target for therapeutic strategies for HCC treatment. [ABSTRACT FROM AUTHOR]