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We present a novel implementation for active galactic nucleus (AGN) feedback through ultrafast winds in the code GIZMO. Our feedback recipe accounts for the angular dependence of radiative feedback on black hole spin. We self-consistently evolve in time (i) the gas-accretion process from resolved scales to a smaller scale unresolved (subgrid) AGN disk, (ii) the evolution of the spin of the massive black hole (MBH), (iii) the injection of AGN-driven winds into the resolved scales, and (iv) the spin-induced anisotropy of the overall feedback process. We tested our implementation by following the propagation of the wind-driven outflow into an homogeneous medium, and here we present a comparison of the results against simple analytical models. We also considered an isolated galaxy setup, where the galaxy is thought to be formed from the collapse of a spinning gaseous halo, and there we studied the impact of the AGN feedback on the evolution of the MBH and of the host galaxy. We find that: (i) AGN feedback limits the gas inflow that powers the MBH, with a consequent weak impact on the host galaxy characterized by a suppression of star formation by about a factor of two in the nuclear (≲kpc) region; (ii) the impact of AGN feedback on the host galaxy and on MBH growth is primarily determined by the AGN luminosity rather than by its angular pattern set by the MBH spin (i.e., more luminous AGNs more efficiently suppress central star formation (SF), clearing wider central cavities and driving outflows with larger semiopening angles); (iii) the imprint of the angular pattern of AGN radiation emission is detected more clearly at high (i.e., Eddington) accretion rates. At such high rates, the more isotropic angular patterns, as occur for high spin values, sweep away gas in the nuclear region more easily, therefore causing a slower MBH mass and spin growths and a higher quenching of SF. We argue that the influence of spin-dependent anisotropy of AGN feedback on MBH and galaxy evolution is likely to be relevant in those scenarios characterized by high and prolonged MBH accretion episodes and by high AGN wind–galaxy coupling. Such conditions are more frequently met in galaxy mergers and/or high-redshift galaxies. [ABSTRACT FROM AUTHOR]

Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disease due to defective activity of the mitochondrial enzyme sterol 27-hydroxylase. In 1991, sterol 27-hydroxylase gene (CYP27A1) was localised on the long arm of chromosome 2 [1]. Clinical characteristics of CTX are diarrhoea, cataracts, tendon xanthomas and neurological manifestations including dementia, psychiatric disturbances, pyramidal and/or cerebellar signs, and seizures. More than 300 patients with CTX have been reported to date worldwide and about 50 different mutations identified in the CYP27A1 gene. Almost all mutations lead to the absence or inactive form of the sterol 27-hydroxylase. In this review, according with the aims of this section of the journal, we describe the different pathogenetic mutations in the CYP27A1 gene and the main clinical and pathogenetic aspects that may help clinical neurologists in the diagnosis of CTX. [ABSTRACT FROM AUTHOR]

Stellar bars are a common feature in massive disc galaxies. On a theoretical ground, the response of gas to a bar is generally thought to cause nuclear starbursts and, possibly, AGN activity once the perturbed gas reaches the central supermassive black hole. By means of high-resolution numerical simulations, we detail the purely dynamical effects that a forming bar exerts on the gas of an isolated disc galaxy. The galaxy is initially unstable to the formation of non-axisymmetric structures, and within ~1 Gyr it develops spiral arms that eventually evolve into a central stellar bar on kpc scale. A first major episode of gas inflow occurs during the formation of the spiral arms while at later times, when the stellar bar is establishing, a low-density region is carved between the bar corotational and inner Lindblad resonance radii. The development of such 'dead zone' inhibits further massive gas inflows. Indeed, the gas inflow reaches its maximum during the relatively fast bar-formation phase and not, as often assumed, when the bar is fully formed. We conclude that the low efficiency of long-lived, evolved bars in driving gas towards galactic nuclei is the reason why observational studies have failed to establish an indisputable link between bars and AGNs. On the other hand, the high efficiency in driving strong gas inflows of the intrinsically transient process of bar formation suggests that the importance of bars as drivers of AGN activity in disc galaxies has been overlooked so far. We finally prove that our conclusions are robust against different numerical implementations of the hydrodynamics routinely used in galaxy evolution studies. [ABSTRACT FROM AUTHOR]

Massive black hole binaries are naturally predicted in the context of the hierarchical model of structure formation. The binaries that manage to lose most of their angular momentum can coalesce to form a single remnant. In the last stages of this process, the holes undergo an extremely loud phase of gravitational wave emission, possibly detectable by current and future probes. The theoretical effort towards obtaining a coherent physical picture of the binary path down to coalescence is still underway. In this paper, for the first time, we take advantage of observational studies of active galactic nuclei evolution to constrain the efficiency of gas-driven binary decay. Under conservative assumptions we find that gas accretion towards the nuclear black holes can efficiently lead binaries of any mass forming at high redshift (≳2) to coalescence within the current time. The observed ‘downsizing’ trend of the accreting black hole luminosity function further implies that the gas inflow is sufficient to drive light black holes down to coalescence, even if they bind in binaries at lower redshifts, down to z ≈ 0.5 for binaries of ∼107 M⊙, and z ≈ 0.2 for binaries of ∼106 M⊙. This has strong implications for the detection rates of coalescing black hole binaries of future space-based gravitational wave experiments. [ABSTRACT FROM AUTHOR]

The peculiar QSO J0927+2943 shows multiple sets of emission lines in its optical spectrum. This signature has been interpreted as the relative motion between a black hole, either recoiling or bound in a binary system, and its host galaxy, or as a superposition of two galaxies along the line of sight. In order to test these scenarios, we have collected 2 mm CO(2-1) observations using the IRAM Plateau de Bure Interferometer, and optical images and spectroscopy at the Calar Alto observatory. Together with archival HST images, these data provide unique insights on the nature of this system. The recoiling/binary black hole scenarios are ruled out by the clear detection of a galactic-scale molecular gas reservoir at the same redshift of the QSO broad lines. The observations presented here also disfavour the superposition model, although with less constraints. Thus, the origin of the second, bright set of narrow emission lines in J0927+2943 is still unknown. [ABSTRACT FROM AUTHOR]

ABSTRACT Massive black hole (BH) binaries at sub-parsec separations may display in their spectra anomalously small flux ratios between the Mg ii and C iv broad emission lines, i.e. [ABSTRACT FROM AUTHOR]

The study of the dynamical evolution of massive black hole pairs in mergers is crucial in the context of a hierarchical galaxy formation scenario. The timescales for the formation and the coalescence of black hole binaries are still poorly constrained, resulting in large uncertainties in the expected rate of massive black hole binaries detectable in the electromagnetic and gravitational wave spectra. Here, we review the current theoretical understanding of the black hole pairing in galaxy mergers, with a particular attention to recent developments and open issues. We conclude with a review of the expected observational signatures of massive binaries and of the candidates discussed in literature to date. [ABSTRACT FROM AUTHOR]

ABSTRACT We study the dynamics of supermassive black hole binaries embedded in circumbinary gaseous discs, with the smoothed particle hydrodynamics code gadget-2. The subparsec binary (of total mass M and mass ratio q= 1/3) has excavated a gap and transfers its angular momentum to the self-gravitating disc ( Mdisc= 0.2 M). We explore the changes of the binary eccentricity, e, by simulating a sequence of binary models that differ in the initial eccentricity e0 only. In initially low-eccentric binaries, the eccentricity increases with time, while in high-eccentric binaries e declines, indicating the existence of a limiting eccentricity ecrit that is found to fall in the interval [0.6, 0.8]. We also present an analytical interpretation for this saturation limit. An important consequence of the existence of ecrit is the detectability of a significant residual eccentricity eLISA by the proposed gravitational wave detector Laser Interferometer Space Antenna (LISA). It is found that at the moment of entering the LISA frequency domain eLISA∼ 10−3-10−2, a signature of its earlier coupling with the massive circumbinary disc. We also observe large periodic inflows across the gap, occurring on the binary and disc dynamical time-scales rather than on the viscous time. These periodic changes in the accretion rate (with amplitudes up to ∼100 per cent, depending on the binary eccentricity) can be considered a fingerprint of eccentric subparsec binaries migrating inside a circumbinary disc. [ABSTRACT FROM AUTHOR]

ABSTRACT We study the properties of the broad-line region in blazars by comparing the virial estimate of black hole masses with that derived from the mass of the host galaxies. The former is sensitive to the width of broad lines, i.e. to the projection of the velocity of line-emitting clouds along the line of sight; the latter is not. This comparison allows us to constrain the deprojection factor f, thus revealing general properties of the geometry of the broad-line region. We show that blazars tend to have (1) higher f values than the quasars of our reference sample: 〈 fBLLacs〉= 6.9 ± 2.3; 〈 fblazars〉= 5.6 ± 1.3 and 〈 fquasars〉= 2.0 ± 0.3, (2) relatively narrow broad emission lines and (3) modest equivalent widths, as expected because of the occurrence of jet emission at very low inclination angles. In a disc-like sketch of the broad-line region, these results indicate a pole-on view of a flat geometry in blazars. This consistently extends the orientation-dependent unified model of active nuclei to the geometry of the broad-line region. [ABSTRACT FROM AUTHOR]

We investigate the spectral properties of an active black hole, member of a massive () sub-parsec black hole binary. We work under the hypothesis that the binary, surrounded by a circumbinary disc, has cleared a gap, and that accretion occurs on to the secondary black hole fed by material closer to the inner edge of the disc. Broad line emission clouds orbit around the active black hole and suffer erosion due to tidal truncation at the Roche Lobe surface, following gap opening and orbital decay. We consider three of the most prominent broad emission lines observed in the spectra of active galactic nuclei (AGNs), i.e. C , Mg and , and compute the flux ratios between the lines of Mg and C () and those of Mg and (). We find that close black hole binaries have up to 1 order of magnitude smaller than single black holes. By contrast may be significantly reduced only at the shortest separations. Peculiarly low values of line flux ratios together with large velocity offsets between the broad and narrow emission lines and/or periodic variability in the continuum (on time-scales years) would identify genuine sub-pc binary candidates. [ABSTRACT FROM AUTHOR]

Background and purpose: Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disease, because of sterol 27-hydroxylase deficiency. Clinical manifestations of CTX are tendon xanthomas, juvenile cataracts, osteoporosis, diarrhoea and multiple progressive neurological dysfunctions. More than 300 patients with CTX have been reported to date worldwide and about fifty different mutations identified in CYP27A1 gene. This study describes the clinical and laboratory findings of seven new patients. Methods: We report the molecular and clinical characterization of seven new Italian patients with CTX carrying four novel mutations. Results: We identified four novel mutations located in different exons, in particular in the region of exons 2–5 of the CYP27A1 gene. Phenotypical expression did not differ from classical CTX presentation except for absence of tendon xanthomas in two patients. [ABSTRACT FROM AUTHOR]

Using high-resolution hydrodynamical simulations, we explore the spin evolution of massive dual black holes orbiting inside a circumnuclear disc, relic of a gas-rich galaxy merger. The black holes spiral inwards from initially eccentric co- or counter-rotating coplanar orbits relative to the disc's rotation, and accrete gas that is carrying a net angular momentum. As the black hole mass grows, its spin changes in strength and direction due to its gravito-magnetic coupling with the small-scale accretion disc. We find that the black hole spins loose memory of their initial orientation, as accretion torques suffice to align the spins with the angular momentum of their orbit on a short time-scale . A residual off-set in the spin direction relative to the orbital angular momentum remains, at the level of for the case of a cold disc, and for a warmer disc. Alignment in a cooler disc is more effective due to the higher coherence of the accretion flow near each black hole that reflects the large-scale coherence of the disc's rotation. If the massive black holes coalesce preserving the spin directions set after formation of a Keplerian binary, the relic black hole resulting from their coalescence receives a relatively small gravitational recoil. The distribution of recoil velocities inferred from a simulated sample of massive black hole binaries has median , much smaller than the median resulting from an isotropic distribution of spins. [ABSTRACT FROM AUTHOR]

In this paper, we explore the gravitomagnetic interaction of a black hole (BH) with a misaligned accretion disc to study BH spin precession and alignment jointly with BH mass MBH and spin parameter a evolution, under the assumption that the disc is continually fed, in its outer region, by matter with angular momentum fixed on a given direction . We develop an iterative scheme based on the adiabatic approximation to study the BH–disc co-evolution: in this approach, the accretion disc transits through a sequence of quasi-steady warped states (Bardeen–Petterson effect) and interacts with the BH until the spin aligns with . For a BH aligning with a corotating disc, the fractional increase in mass is typically less than a few per cent, while the spin modulus can increase up to a few tens of per cent. The alignment time-scale is of for a maximally rotating BH accreting at the Eddington rate. BH–disc alignment from an initially counter-rotating disc tends to be more efficient compared to the specular corotating case due to the asymmetry seeded in the Kerr metric: counter-rotating matter carries a larger and opposite angular momentum when crossing the innermost stable orbit, so that the spin modulus decreases faster and so the relative inclination angle. [ABSTRACT FROM AUTHOR]

We study the orbital evolution and accretion history of massive black hole (MBH) pairs in rotationally supported circumnuclear discs up to the point where MBHs form binary systems. Our simulations have high resolution in mass and space which, for the first time, makes it feasible to follow the orbital decay of a MBH either counter- or corotating with respect to the circumnuclear disc. We show that a moving MBH on an initially counter-rotating orbit experiences an ‘orbital angular momentum flip’ due to the gas-dynamical friction, i.e. it starts to corotate with the disc before a MBH binary forms. We stress that this effect can only be captured in very high resolution simulations. Given the extremely large number of gas particles used, the dynamical range is sufficiently large to resolve the Bondi–Hoyle–Lyttleton radii of individual MBHs. As a consequence, we are able to link the accretion processes to the orbital evolution of the MBH pairs. We predict that the accretion rate is significantly suppressed and extremely variable when the MBH is moving on a retrograde orbit. It is only after the orbital angular momentum flip has taken place that the secondary rapidly ‘lights up’ at which point both MBHs can accrete near the Eddington rate for a few Myr. The separation of the double nucleus is expected to be around ≲10 pc at this stage. We show that the accretion rate can be highly variable also when the MBH is corotating with the disc (albeit to a lesser extent) provided that its orbit is eccentric. Our results have significant consequences for the expected number of observable double active galactic nuclei at separations of ≲100 pc. [ABSTRACT FROM AUTHOR]

Objective: To assess, by using quantitative MRI metrics, structural and metabolic brain abnormalities in subjects with preclinical cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL). Background: Brain MRI abnormalities have been occasionally reported in preclinical CADASIL subjects. However, very little is known as to when the brain tissue damage starts to accumulate, what brain regions are primarily involved and whether the brain damage is significant in subjects who have no overt clinical manifestations of the disease. Methods: Twelve subjects (mean age 40 years; range 26-55 years; males/females 6/6) with genetically proven CADASIL and no clinical signs of the disease underwent conventional MRI and proton MR spectroscopic imaging (H-MRSI) to measure white matter (WM) lesion volume ILVI, global and regional cerebral volumes, and WM levels of N-acetylaspartate (NAA) normalised to creatine (Cr). MR values were compared with those of 13 age- and sex- matched healthy controls. Results: All preclinical CADASIL showed WM lesions (range 0.2 to 26 cm3). They were mostly distributed in the frontal and parietal regions, with the highest probability in the corona radiata. On ¹H-MRSI examination, NAN/Cr values were lower in preclinical CADASIL than in HC, particularly in the corona radiata (p<0.01). Normalised brain and cortical volumes were also lower in preclinical CADASIL than in HC (p<0.01), particularly in the frontal cortex. Conclusions: The pathological process occurring in CADASIL leads to damage of WM and neocortex much before the evidence of clinical symptoms. At this preclinical stage, this seems to take place prevalently in the frontal brain region. [ABSTRACT FROM AUTHOR]

The dynamics of two massive black holes in a rotationally supported nuclear disc of mass is explored using N-body/smoothed particle hydrodynamics simulations. Gas and star particles are copresent in the disc. Described by a Mestel profile, the disc has a vertical support provided by turbulence of the gas, and by stellar velocity dispersion. A primary black hole of mass is placed at the centre of the disc, while a secondary black hole is set initially on an eccentric corotating orbit in the disc plane. Its mass is in a 1:1, 1:4, and 1:10 ratio, relative to the primary. With this choice, we mimic the dynamics of black hole pairs released in the nuclear region at the end of a gas-rich galaxy merger. It is found that, under the action of dynamical friction, the two black holes form a close binary in ∼10 Myr. The inspiral process is insensitive to the mass fraction in stars and gas present in the disc and is accompanied by the circularization of the orbit. We detail the gaseous mass profile bound to each black hole that can lead to the formation of two small Keplerian discs, weighing ≈2 per cent of the black hole mass, and of size ∼0.01 pc. The mass of the tightly (loosely) bound particles increases (decreases) with time as the black holes spiral into closer and closer orbits. Double active galactic nucleus activity is expected to occur on an estimated time-scale of ≲10 Myr, comparable to the inspiral time-scale. The double nuclear point-like sources that may appear during dynamical evolution will have typical separations of ≲10 pc. [ABSTRACT FROM AUTHOR]

We explore the nature of possible electromagnetic counterparts of coalescences of massive black hole binaries at cosmological distances detectable by the Laser Interferometer Space Antenna ( LISA). An electromagnetic precursor, during the last year of gravitational wave (GW)-driven inspiral, or an afterglow within few years after coalescence, may highlight the position in the sky of galaxies hosting the LISA sources. We show that observations of precursors and afterglows are mutually exclusive, depending on the mass of the primary black hole. Precursors are expected to occur in binaries where the primary (more massive) black hole is heavier than . They may correspond to on–off states of accretion, that is, to a bright X-ray source decaying into quiescence before black hole coalescence, and are likely associated to disturbed galaxies showing signs of ongoing starbursts. Coalescences of lighter binaries, with masses , lack of any precursor, as gas is expected to be consumed long before the GW-driven orbital decay. Such events would not be hosted by (massive) galaxies with an associated starburst, given the slow binary inspiral time compared to the typical time-scale of starbursts. In contrast, coalescence, for such light binaries, is followed by an electromagnetic afterglow, that is, an off–on accretion state rising in 20 yr. Using a cosmological merger tree algorithm, we show that future X-ray missions such as the XEUS will be able to identify, in 20-yr operation, almost all the massive BH binaries detectable by the LISA and, in only 5 yr, all the LISA sources at . [ABSTRACT FROM AUTHOR]

Abstract: Mutations of the Cav-3 gene are associated with distinct, sometimes overlapping muscle disease phenotypes. We report a new Italian family with autosomal dominant rippling muscle disease. Immunocytochemical analysis of muscle showed a deficit of caveolin-3 protein and molecular genetic analysis showed a novel mutation of the Cav-3 gene. [Copyright &y& Elsevier]

The concentrations of serum cholesterol, cholestanol and non-cholesterol sterols were measured in a patient with cerebrotendinous xanthomatosis under different therapeutic regimens. During treatment with chenodeoxycholic acid (CDCA) (750 mg/day) plus simvastatin (20 mg/day) for two years cholesterol and cholestanol concentrations averaged 188±10 mg/dl and 0.54±0.03 mg/dl. Thereafter treatment with simvastatin was discontinued. During treatment with low-density lipoprotein (LDL)-apheresis plus CDCA for 33 weeks, cholestanol concentrations reached almost normal levels (0.48±0.03 mg/dl immediately before and 0.32±0.02 mg/dl directly after LDL-apheresis, n=6). A further reduction of cholesterol and cholestanol was achieved by addition of simvastatin (20 mg/day). Cholesterol and cholestanol concentrations before and after LDL-apheresis during this treatment period averaged 122±4 mg/dl and 55±10 mg/dl, and 0.42±0.02 mg/dl and 0.18±0.06 mg/dl, respectively. Despite the consistent reduction of cholestanol to normal or even subnormal levels, a definite improvement of clinical symptoms was not noted. Our results suggest caution in the recourse to an aggressive cholestanol lowering therapy. [ABSTRACT FROM AUTHOR]

Quasi-periodic eruptions (QPEs) are repeated X-ray flares from galactic nuclei that recur every few hours to days, depending on the source. Despite some diversity in the recurrence and amplitude of eruptions, their striking regularity has motivated theorists to associate QPEs with orbital systems. Among the known QPE sources, eRO-QPE2 has shown the most regular flare timing and luminosity since its discovery. We report here on its long-term evolution over 3.3 yr from discovery and find that: i) the average QPE recurrence time per epoch has decreased over time, albeit not at a uniform rate; ii) the distinct alternation between consecutive long and short recurrence times found at discovery has not been significant since; iii) the spectral properties, namely flux and temperature of both eruptions and quiescence components, have remained remarkably consistent within uncertainties. We attempted to interpret these results as orbital period and eccentricity decay coupled with orbital and disk precession. However, since gaps between observations are too long, we are not able to distinguish between an evolution dominated by just a decreasing trend, or by large modulations (e.g. due to the precession frequencies at play). In the former case, the observed period decrease is roughly consistent with that of a star losing orbital energy due to hydrodynamic gas drag from disk collisions, although the related eccentricity decay is too fast and additional modulations have to contribute too. In the latter case, no conclusive remarks are possible on the orbital evolution and the nature of the orbiter due to the many effects at play. However, these two cases come with distinctive predictions for future X-ray data: in the case of a decreasing trend, we expect all future observations to show a shorter recurrence time than the latest epoch, while in the case of large-amplitude modulations we expect some future observations to be found with a larger recurrence, hence an apparent temporary period increase. [ABSTRACT FROM AUTHOR]

A letter to the editor about a family having cerebellar atrophy, mental retardation and abnormal pupils is presented.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL) is an inherited cerebrovascular disease due to mutations of the Notch3 gene at the chromosome locus 19p13. The clinical spectrum includes recurrent ischaemic episodes, cognitive deficits, migraine and psychiatric disorders. The histopathological hallmark of CADASIL is accumulation of electron dense granules (GOM) in the media of arterioles. MRI reveals extensive cerebral white matter lesions and subcortical infarcts. CADASIL was initially thought to be a rare disorder, but increasing numbers of families have been identified; therefore, it is likely that CADASIL is still largely underdiagnosed. Here we report an update on mutations of the Notch3 gene and some information on the pathogenesis of the disease. [ABSTRACT FROM AUTHOR]

In this Letter, we explore the hypothesis that the quasar SDSSJ092712.65+294344.0 is hosting a massive black hole binary embedded in a circumbinary disc. The lightest, secondary black hole is active, and gas orbiting around it is responsible for the blue-shifted broad emission lines with velocity off-set of 2650 km s−1, relative to the galaxy rest frame. As the tidal interaction of the binary with the outer disc is expected to excavate a gap, the blue-shifted narrow emission lines are consistent with being emitted from the low-density inhomogeneous gas of the hollow region. From the observations, we infer a binary mass ratio , a mass for the primary of , and a semimajor axis of 0.34 pc, corresponding to an orbital period of 370 years. We use the results of cosmological merger trees to estimate the likelihood of observing SDSSJ092712.65+294344.0 as recoiling black hole or as a binary. We find that the binary hypothesis is preferred being 100 times more probable than the ejection hypothesis. If SDSSJ092712.65+294344.0 hosts a binary, it would be the one closest massive black hole binary system ever discovered. [ABSTRACT FROM AUTHOR]

Massive black hole binaries (BHBs) are expected to be one of the most powerful sources of gravitational waves in the frequency range of the pulsar timing array and of forthcoming space-borne detectors. They are believed to form in the final stages of galaxy mergers, and then harden by slingshot ejections of passing stars. However, evolution via the slingshot mechanism may be ineffective if the reservoir of interacting stars is not readily replenished, and the binary shrinking may come to a halt at roughly a parsec separation. Recent simulations suggest that the departure from spherical symmetry, naturally produced in merger remnants, leads to efficient loss cone refilling, preventing the binary from stalling. However, current N-body simulations able to accurately follow the evolution of BHBs are limited to very modest particle numbers. Brownian motion may artificially enhance the loss cone refilling rate in low-N simulations, where the binary encounters a larger population of stars due its random motion. Here we study the significance of Brownian motion of BHBs in merger remnants in the context of the final parsec problem. We simulate mergers with various particle numbers (from 8k to 1M) and with several density profiles. Moreover, we compare simulations where the BHB is fixed at the centre of the merger remnant with simulations where the BHB is free to random walk. We find that Brownian motion does not significantly affect the evolution of BHBs in simulations with particle numbers in excess of one million, and that the hardening measured in merger simulations is due to collisionless loss cone refilling. [ABSTRACT FROM AUTHOR]

The rapid assembly of the massive black holes that power the luminous quasars observed at z ~ 6-7 remains a puzzle. Various direct collapse models have been proposed to head-start black hole growth from initial seeds with masses~105M⊙, which can then reach a billion solar mass while accreting at the Eddington limit. Here, we propose an alternative scenario based on radiatively inefficient supercritical accretion of stellar-mass holes embedded in the gaseous circumnuclear discs (CNDs) expected to exist in the cores of high-redshift galaxies. Our sub-pc resolution hydrodynamical simulations show that stellar-mass holes orbiting within the central 100 pc of the CND bind to very high density gas clumps that arise from the fragmentation of the surrounding gas. Owing to the large reservoir of dense cold gas available, a stellar-mass black hole allowed to grow at super-Eddington rates according to the 'slim-disc' solution can increase its mass by three orders of magnitudes within a few million years. These findings are supported by simulations run with two different hydro codes, RAMSES based on the Adaptive Mesh Refinement technique and GIZMO based on a new Lagrangian Godunov-type method, and with similar, but not identical, sub-grid recipes for star formation, supernova feedback, black hole accretion and feedback. The low radiative efficiency of supercritical accretion flows are instrumental to the rapid mass growth of our black holes, as they imply modest radiative heating of the surrounding nuclear environment. [ABSTRACT FROM AUTHOR]

Nuclear stellar discs (NSDs) can help to constrain the assembly history of their host galaxies, as long as we can assume them to be fragile structures that are disrupted during merger events. In this work we investigate the fragility of NSDs by means of N-body simulations reproducing the last phases of a galaxy encounter, when the nuclear regions of the two galaxies merge. For this, we exposed an NSD set in the gravitational potential of the bulge and supermassive black hole of a primary galaxy to the impact of the supermassive black hole from a secondary galaxy. We explored merger events of different mass ratios, from major mergers with a 1:1 mass ratio to intermediate and minor interactions with 1:5 and 1:10 ratios, while considering various impact geometries. We analyse the end results of such mergers from different viewing angles and look for possible photometric and kinematic signatures of the presence of a disc in the remnant surface density and velocity maps, while adopting detection limits from real observations. Our simulations show that indeed NSDs are fragile against major mergers, which leave little trace of NSDs both in images and velocity maps, while signatures of a disc can be found in the majority of the intermediate to minor-merger remnants and in particular when looking at their kinematics. These results show that NSDs could allow us to distinguish between these two modes of galaxy assembly, which may indeed pertain to different kinds of galaxies or galactic environments. [ABSTRACT FROM AUTHOR]

Nuclear stellar discs (NSDs) can help to constrain the assembly history of their host galaxies, as long as we can assume them to be fragile structures that are disrupted during merger events. In this work we investigate the fragility of NSDs by means of N-body simulations reproducing the last phases of a galaxy encounter, when the nuclear regions of the two galaxies merge. For this, we exposed an NSD set in the gravitational potential of the bulge and supermassive black hole of a primary galaxy to the impact of the supermassive black hole from a secondary galaxy. We explored merger events of different mass ratios, frommajor mergerswith a 1:1 mass ratio to intermediate and minor interactions with 1:5 and 1:10 ratios, while considering various impact geometries. We analyse the end results of such mergers from different viewing angles and look for possible photometric and kinematic signatures of the presence of a disc in the remnant surface density and velocity maps, while adopting detection limits from real observations. Our simulations show that indeed NSDs are fragile against major mergers, which leave little trace of NSDs both in images and velocity maps, while signatures of a disc can be found in the majority of the intermediate to minor-merger remnants and in particular when looking at their kinematics. These results show that NSDs could allow us to distinguish between these two modes of galaxy assembly, which may indeed pertain to different kinds of galaxies or galactic environments. [ABSTRACT FROM AUTHOR]

A growing body of evidence indicates that the star formation rate per unit stellar mass (sSFR) decreases with increasing mass in normal main-sequence star-forming galaxies. Many processes have been advocated as being responsible for this trend (also known as mass quenching), e.g., feedback from active galactic nuclei (AGNs), and the formation of classical bulges. In order to improve our insight into the mechanisms regulating the star formation in normal star-forming galaxies across cosmic epochs, we determine a refined star formation versus stellar mass relation in the local Universe. To this end we use the Hα narrow-band imaging followup survey (Hα3) of field galaxies selected from the HI Arecibo Legacy Fast ALFA Survey (ALFALFA) in the Coma and Local superclusters. By complementing this local determination with high-redshift measurements from the literature, we reconstruct the star formation history of main-sequence galaxies as a function of stellar mass from the present epoch up to z = 3. In agreement with previous studies, our analysis shows that quenching mechanisms occur above a threshold stellar mass Mknee that evolves with redshift as ∞(1 + z)2. Moreover, visual morphological classification of individual objects in our local sample reveals a sharp increase in the fraction of visually classified strong bars with mass, hinting that strong bars may contribute to the observed downturn in the sSFR above Mknee. We test this hypothesis using a simple but physically motivated numerical model for bar formation, finding that strong bars can rapidly quench star formation in the central few kpc of field galaxies. We conclude that strong bars contribute significantly to the red colors observed in the inner parts of massive galaxies, although additional mechanisms are likely required to quench the star formation in the outer regions of massive spiral galaxies. Intriguingly, when we extrapolate our model to higher redshifts, we successfully recover the observed redshift evolution for Mknee. Our study highlights how the formation of strong bars in massive galaxies is an important mechanism in regulating the redshift evolution of the sSFR for field main-sequence galaxies. [ABSTRACT FROM AUTHOR]

We present the results of a systematic search for massive black hole binaries in the Sloan Digital Sky Survey (SDSS) spectroscopic database. We focus on bound binaries, under the assumption that one of the black holes is active. In this framework, the broad lines associated with the accreting black hole are expected to show systematic velocity shifts with respect to the narrow lines, which trace the rest frame of the galaxy. For a sample of 54,586 quasars and 3929 galaxies at redshifts 0.1 < z < 1.5, we brute-force model each spectrum as a mixture of two quasars at two different redshifts. The spectral model is a data-driven dimensionality reduction of the SDSS quasar spectra based on a matrix factorization. We identified 32 objects with peculiar spectra. Nine of them can be interpreted as black hole binaries. This doubles the number of known black hole binary candidates. We also report on the discovery of a new class of extreme double-peaked emitters with exceptionally broad and faint Balmer lines. For all the interesting sources, we present detailed analysis of the spectra and discuss possible interpretations. [ABSTRACT FROM AUTHOR]

Nuclear stellar discs (NSDs), of a few tens to hundreds of parsec across, are a common and yet poorly studied feature of early-type galaxies. Still, such small discs represent a powerful tool to constrain the assembling history of galaxies, since they can be used to trace to the epoch when galaxies experienced their last major merger event. By studying the fraction and stellar age of NSDs, it is thus possible to test the predictions for the assembly history of early-type galaxies according to the current hierarchical paradigm for galaxy formation. In this paper we have produced the most comprehensive census of NSDs in nearby early-type galaxies by searching for such discs in objects within 100 Mpc and by using archival images from the Hubble Space Telescope. We found that NSDs are present in approximately 20 per cent of early-type galaxies, and that the fraction of galaxies with NSDs depends neither on their Hubble type nor on their galactic environment, whereas the incidence of NSDs appears to decline in the most massive systems. Furthermore, we have separated the light contribution of 12 such discs from that of their surrounding stellar bulge in order to extract their physical properties. This doubles the number of decomposed NSDs and although the derived values for their central surface brightness and scalelength are consistent with previous studies, they also give a hint of possible different characteristics due to different formation scenario between nuclear discs and other kinds of large galactic discs. [ABSTRACT FROM AUTHOR]

We present a photometric far-ultraviolet (FUV) to Ks-band study of the field around quasar SDSS J092712.65+294344.0. The SDSS spectrum of this object shows various emission lines with two distinct redshifts, at and 0.712. Because of this peculiar spectroscopic feature, this source has been proposed as a candidate recoiling or binary black hole. A third alternative model involves two galaxies moving in the centre of a rich galaxy cluster. Here, we present a study addressing the possible presence of such a rich cluster of galaxies in the SDSS J092712.65+294344.0 field. We observed the arcmin2 field in the Ks band and matched the near-infrared data with the FUV and near-ultraviolet images in the Galaxy Evolution Explorer archive and the ugriz observations in the SDSS. From various colour–colour diagrams, we were able to classify the nature of 32 sources, only 6–11 of which have colours consistent with galaxies at . We compare these numbers with the surface density of galaxies, stars and quasars and the expectations for typical galaxy clusters both at low and high redshift. Our study shows that the galaxy cluster scenario is in clear disagreement with the new observations. [ABSTRACT FROM AUTHOR]

Anisotropic gravitational radiation from a coalescing black hole (BH) binary is known to impart recoil velocities of up to to the remnant BH. In this context, we study the motion of a recoiling BH inside a galaxy modelled as a Hernquist sphere, and the signature that the hole imprints on the hot gas, using N-body/smoothed particle hydrodynamics simulations. Ejection of the BH results in a sudden expansion of the gas ending with the formation of a gaseous core, similarly to what is seen for the stars. A cometary tail of particles bound to the BH is initially released along its trail. As the BH moves on a return orbit, a nearly spherical swarm of hot gaseous particles forms at every apocentre: this feature can live up to ≈108 years. If the recoil velocity exceeds the sound speed initially, the BH shocks the gas in the form of a Mach cone in density near each supersonic pericentric passage. We find that the X-ray fingerprint of a recoiling BH can be detected in Chandra X-ray maps out to a distance of Virgo. For exceptionally massive BHs, the Mach cone and the wakes can be observed out to a few hundred of milliparsec. The detection of the Mach cone is of twofold importance as it can be a probe of high-velocity recoils, and an assessment of the scatter of the relation at large BH masses. [ABSTRACT FROM AUTHOR]

Visual impairment due to retinal and optic nerve changes in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is more common than previously thought. Deposits of granular osmiophilic material (GOM) have been shown in the wall of retinal arterioles, though retinal infarcts and vascular occlusions have never been reported. Ischaemic optic neuropathy, on the other hand, has been reported in one case of CADASIL but no pathology reports of the optic nerve have been published. Here we report optic nerve morphological findings in the autopsy material of a 41-year-old woman with genetically assessed CADASIL. Longitudinal and transverse sections of optic nerves were examined. Classical histological methods (haematoxylin-eosin and Nissl) were performed. Diffuse pallor of myelin and rarefaction of optic nerve fibres were observed. Classical GOM was evident in the tunica media of vessels in the meninges and white matter. Arteriole lumina were slightly narrowed. In conclusion, the typical pathological changes of CADASIL occur in the optic nerve and may contribute to impairment of visual function in CADASIL. [ABSTRACT FROM AUTHOR]

A numerical model able to investigate the influence of biomedical factors on the long-term secondary stability of implants would be extremely useful for the design of new cementless prosthetic devices. A purely biomechanical model of osseo-integration has been developed, formulated as a rule-based adaptation scheme. Due to its complexity, the problem was divided into three steps: preliminary implementation of the model (proof of concept); implementation of the complete model and investigation of the model solution; and model validation. The paper describes the first of these three steps. The model was implemented as a discrete-states machine, and the few parameters required were derived from the literature. It was then applied to a real clinical case. The study was conducted using the frictional contact finite element model of a human femur implanted with a cementless anatomical stem. A stable solution was achieved after between three and 15 iterations for all initial positions considered. Similar initial conditions yielded similar final configurations. The model predicted all initial configurations, with the exception of a partial osseo-integration, ranging between 62% (distal fit) and 78% (proximal fit) of the viable interface. This is in good agreement with the values reported in the literature that never exceed 75%, even in the best conditions, and report better clinical results for proximal fit. For the varus configuration, which lacks cortical support, the algorithm predicted a completed loosening. [ABSTRACT FROM AUTHOR]

A numerical model able to investigate the influence of biomechanical factors on the long-term secondary stability of implants would be extremely useful for the design of new cementless prosthetic devices. A purely biomechanical model of osseo-integration has been developed, formulated as a rule-based adaptation scheme. Due to its complexity, the problem was divided into three steps: preliminary implementation of the model (proof of concept); implementation of the complete model and investigation of the model solution; and model validation. The paper describes the first of these three steps. The model was implemented as a discrete-states machine, and the few parameters required were derived from the literature. It was then applied to a real clinical case. The study was conducted using the frictional contact finite element model of a human femur implanted with a cementless anatomical stem. A stable solution was achieved after between three and 15 iterations for all initial positions considered. Similar initial conditions yielded similar final configurations. The model predicted all initial configurations, with the exception of a partial osseo-integration, ranging between 62% (distal fit) and 78% (proximal fit) of the viable interface. This is in good agreement with the values reported in the literature that never exceed 75%, even in the best conditions, and report better clinical results for proximal fit. For the varus configuration, which lacks cortical support, the algorithm predicted a completed loosening. [ABSTRACT FROM AUTHOR]

Short-chain-acyl-CoA-dehydrogenase (SCAD) deficiency is an inborn error of mitochondrial fatty acid metabolism caused by rare mutations as well as common susceptibility variations in the SCAD gene. We describe the case of a 23-year-old male patient who had growth and mental retardation, recurrent vomiting, fever and seizures since infancy. Urinary gas chromatography and (1)H-nuclear magnetic resonance showed elevated levels of ethylmalonic acid. Serum concentrations of acylcarnitine, especially butyrylcarnitine (C4), were abnormally high. A homozygous variant allele of the SCAD gene, 625G>A, was detected. The patient broadens the clinical phenotype of SCAD deficiency and underlines the difficulty of diagnosis. The limited number of patients described may be the result of underdiagnosis. [ABSTRACT FROM AUTHOR]

We report the first Atacama large millimeter/submillimeter array observations of MCG-03-58-007, a local (z  = 0.03236 ± 0.00002, this work) AGN (⁠|$L_{\mathrm{ AGN}\mathrm{ }}\sim 10^{45}~\rm erg~s^{-1}$|⁠), hosting a powerful X-ray ultrafast (v  = 0.1 c) outflow (UFO). The CO(1-0) line emission is observed across ∼18 kpc scales with a resolution of |$\sim 1\, \rm kpc$|⁠. About 78 per cent of the CO(1-0) luminosity traces a galaxy-size rotating disc. However, after subtracting the emission due to such rotating disc, we detect with a S/N = 20 a residual emission in the central ∼4 kpc. Such residuals may trace a low velocity (v LOS = 170 km s−1) outflow. We compare the momentum rate (⁠|$\dot{P}$|⁠) and kinetic power (⁠|$\dot{E}$|⁠) of such putative molecular outflow with that of the X-ray UFO and find |$\dot{P}_{\mathrm{ mol}}/\dot{P}_{\mathrm{ UFO}}\sim 0.4$| and |$\dot{E}_{\mathrm{ mol}}/\dot{E}_{\mathrm{ UFO}}\sim 4\times 10^{-3}$|⁠. This result is at odds with the energy-conserving scenario suggested by the large momentum boosts measured in some other molecular outflows. An alternative interpretation of the residual CO emission would be a compact rotating structure, distinct from the main disc, which would be a factor of ∼10–100 more extended and massive than typical circumnuclear discs revealed in Seyferts. In conclusion, in both scenarios, our results rule out the hypothesis of a momentum-boosted molecular outflow in this AGN, despite the presence of a powerful X-ray UFO. [ABSTRACT FROM AUTHOR]

Introduction: Adult‐onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP), previously known as hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS) or pigmentary orthochromatic leukodystrophy (POLD), is the most frequent non‐vascular adult‐onset leukoencephalopathy. It is caused by autosomal dominant mutations in CSF1R gene. Recently, also autosomal recessive mutations in AARS2 gene were found to be the cause of an adult‐onset leukodystrophy with axonal spheroids. Our aim was to achieve a genetic diagnosis in a cohort of CSF1R‐negative patients, performing a sequence analysis of AARS2 gene. Material and Methods: AARS2 sequencing was performed in 38 CSF1R‐negative patients with clinical and magnetic resonance imaging (MRI) findings of adult‐onset leukoencephalopathy. Results: Three patients carrying AARS2 compound heterozygous mutations have been found. All patients were female with ovarian failure and leukoencephalopathy. In 2 patients, MRI findings were consistent with previous reports while the third patient showed focal white matter (WM) lesions in the centrum semiovale and the corpus callosum in the absence of extensive involvement and rarefaction of the WM. MRI spectroscopy showed the presence of increased lactate in 2 patients, thus linking AARS2‐related leukoencephalopathy with other mitochondrial leukoencephalopathies with high levels of cerebral lactate. Conclusion: We recommend screening for mutations in AARS2 gene in CSF1R‐negative patients, also in the absence of a clear family history and peculiar MRI findings. Our results also suggest that findings of conventional MRI and MR spectroscopy may be useful in prompting the genetic screening. [ABSTRACT FROM AUTHOR]

Massive black hole (MBH) binaries, formed as a result of galaxy mergers, are expected to harden by dynamical friction and three-body stellar scatterings, until emission of gravitational waves (GWs) leads to their final coalescence. According to recent simulations, MBH binaries can efficiently harden via stellar encounters only when the host geometry is triaxial, even if only modestly, as angular momentum diffusion allows an efficient repopulation of the binary loss cone. In this paper, we carry out a suite of N-body simulations of equal-mass galaxy collisions, varying the initial orbits and density profiles for the merging galaxies and running simulations both with and without central MBHs. We find that the presence of an MBH binary in the remnant makes the system nearly oblate, aligned with the galaxy merger plane, within a radius enclosing 100 MBH masses. We never find binary hosts to be prolate on any scale. The decaying MBHs slightly enhance the tangential anisotropy in the centre of the remnant due to angular momentum injection and the slingshot ejection of stars on nearly radial orbits. This latter effect results in about 1 per cent of the remnant stars being expelled from the galactic nucleus. Finally, we do not find any strong connection between the remnant morphology and the binary hardening rate, which depends only on the inner density slope of the remnant galaxy. Our results suggest that MBH binaries are able to coalesce within a few Gyr, even if the binary is found to partially erase the merger-induced triaxiality from the remnant. [ABSTRACT FROM AUTHOR]

Models and observations suggest that luminous quasar activity is triggered by mergers, so it should preferentially occur in the most massive primordial dark matter haloes, where the frequency of mergers is expected to be the highest. Since the importance of galaxy mergers increases with redshift, we identify the high-redshift Universe as the ideal laboratory for studying dualAGN. Here, we present the X-ray properties of two systems of dual quasars at z= 3.0-3.3 selected from the SDSS DR6 at separations of 6-8 arcsec (43-65 kpc) and observed by Chandra for ≈65 ks each. Both members of each pair are detected with good photon statistics to allow us to constrain the column density, spectral slope and intrinsic X-ray luminosity. We also include a recently discovered dual quasar at z = 5 (separation of 21 arcsec, 136 kpc) for which XMM-Newton archival data allow us to detect the two components separately. Using optical spectra we derived bolometric luminosities, BH masses and Eddington ratios that were compared to those of luminous SDSS quasars in the same redshift ranges. We find that the brighter component of both quasar pairs at z ≈ 3.0-3.3 has high luminosities compared to the distribution of SDSS quasars at similar redshift, with J1622A having an order magnitude higher luminosity than the median. This source lies at the luminous end of the z ≈ 3.3 quasar luminosity function. While we cannot conclusively state that the unusually high luminosities of our sources are related to their having a close companion, for J1622A there is only a 3 per cent probability that it is by chance. [ABSTRACT FROM AUTHOR]

The origin of the nuclear star cluster in the centre of our Galaxy is still unknown.One possibility is that it formed after the disruption of stellar clusters that spiralled into the Galactic Centre due to dynamical friction.We trace the formation of the nuclear star cluster around the central black hole, using state-of-the-art N-body simulations, and follow the dynamics of the neutron stars born in the clusters.We then estimate the number of millisecond pulsars (MSPs) that are released in the nuclear star cluster during its formation. The assembly and tidal dismemberment of globular clusters lead to a population ofMSPs distributed over a radius of about 20 pc, with a peak near 3 pc. No clustering is found on the subparsec scale. We simulate the detectability of this population with future radio telescopes like the MeerKAT radio telescope and SKA1, and find that about an order of 10 MSPs can be observed over this large volume, with a paucity of MSPs within the central parsec. This helps discriminating this scenario from the in situ formation model for the nuclear star cluster that would predict an overabundance of MSPs closer to the black hole. We then discuss the potential contribution of our MSP population to the gamma-ray excess at the Galactic Centre. [ABSTRACT FROM AUTHOR]

We present QSFIT (Quasar Spectral Fitting package), a new software package to automatically perform the analysis of active galactic nuclei (AGNs) optical spectra. The software provides luminosity estimates for the AGN continuum, the Balmer continuum, both optical and ultraviolet iron blended complex, host galaxy and emission lines, as well as width, velocity offset and equivalent width of 20 emission lines. Improving on a number of previous studies on AGN spectral analysis, QSFIT fits all the components simultaneously, using an AGN continuum model which extends over the entire available spectrum, and is thus a probe of the actual AGN continuum whose estimates are scarcely influenced by localized features (e.g. emission lines) in the spectrum. We used QSFIT to analyse 71 251 optical spectra of Type 1 AGN at z < 2 (obtained by the Sloan Digital Sky Survey, SDSS) and to produce a publicly available catalogue of AGN spectral properties. Such catalogue allowed us (for the first time) to estimate the AGN continuum slope and the Balmer continuum luminosity on a very large sample, and to show that there is no evident correlation between these quantities the redshift. All data in the catalogue, the plots with best-fitting model and residuals, and the IDL code we used to perform the analysis, are available on a dedicated website. The whole fitting process is customizable for specific needs, and can be extended to analyse spectra from other data sources. The ultimate purpose of QSFIT is to allow astronomers to run standardized recipes to analyse the AGN data, in a simple, replicable and shareable way. [ABSTRACT FROM AUTHOR]

Objectives Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy ( CADASIL) is an inherited cerebral small vessel disease caused by NOTCH3 gene mutations. CADASIL women are frequently considered at high risk of systemic vascular events during pregnancy and often prescribed with antithrombotic drugs. This decision is not evidence-based considering the lack of data about pregnancy outcome in CADASIL. We describe our experience on pregnancy in CADASIL patients. Materials and methods We reviewed records of 50 CADASIL females followed in our center, and we collected prospective information in six patients for a total of 93 pregnancies. Results No woman had the disease onset or suffered from cerebral vascular ischemic events during pregnancy. Sixteen miscarriages (17.2%) were recorded. There were 72 vaginal births, and five cesarean sections. Considering the six patients followed prospectively (for a total of eight pregnancies), data on fetal growth and newborns weight were in line with those from the general population. Considering gestational complications, we recorded mild proteinuria without hypertension in one patient and hyperinsulinemia and pre-eclampsia in another affected by a known nephropathy. Antithrombotic drugs were used in three patients, in one for an unrelated coexisting prothrombotic condition. Conclusions CADASIL does not seem to be associated with an unfavorable outcome of pregnancy either for women and fetuses. Patients and treating physicians should be reassured that pregnancy can be safely initiated in CADASIL, as there is no evidence to support a specific preventive antithrombotic treatment during pregnancy in CADASIL. Larger studies are needed to definitively confirm these conclusions. [ABSTRACT FROM AUTHOR]

Approximately 20 per cent of early-type galaxies host small nuclear stellar discs that are tens to a few hundred parsecs in size. Such discs are expected to be easily disrupted during major galactic encounters, hence their age serve to constrain their assembly history. We use VIsible MultiObject Spectrograph integral-field spectroscopic observations for the intermediate-mass E0 galaxy NGC 4458 and age-date its nuclear disc via high-resolution fitting of various model spectra. We find that the nuclear disc is at least 6 Gyr old. A clue to gain narrow limits to the stellar age is our knowledge of the nuclear disc contribution to the central surface brightness. The presence of an old nuclear disc, or the absence of disruptive encounters since z ∼ 0.6, for a small galaxy such as NGC 4458 which belongs to the Virgo cluster, may be consistent with a hierarchical picture for galaxy formation where the smallest galaxies assembles earlier and the crowded galactic environments reduce the incidence of galaxy mergers. On the other hand, NGC 4458 displays little or no bulk rotation except for a central kpc-scale kinematically decoupled core. Slow rotation and decoupled core are usually explained in terms of mergers. The presence and age of the nuclear disc constraint these mergers to have happened at high redshift. [ABSTRACT FROM AUTHOR]

This article focuses on a study related to white matter abnormalities on MRI in neoroacanthocytosis. euroacanthocytosis denotes a group of uncommon heterogenous neurode generative disorders associated with acanthocytosis in the absence of any lipid abnormality. In a reported case, a patient who was 6l years, and had been well until 3 years previously when he took early retirement from teaching owing to "disillusionment". He first presented to a neurologist having had an isolated generalised tonic-clonic seizure.

Objectives Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy ( CADASIL) is an inherited small vessel disease caused by NOTCH3 mutations. There are no clinical and neuroimaging findings pathognomonic of the disease. The aim of this paper was to provide a description of a group of NOTCH3-negative patients with a phenotype closely resembling that of CADASIL. Materials and methods We performed NOTCH3 analysis (exons 2-23) in 117 probands because of a clinician's suspicion of CADASIL. The CADASIL scale, a recently developed tool that allows to better select patients for NOTCH3 analysis, was retrospectively applied to NOTCH3-negative patients; the patient subgroup that scored higher than the screening cutoff for CADASIL was defined as CADASIL-like. Results Thirty-four CADASIL-like patients (mean age at onset 57.8 years [52.1-63.4], 50% males) were identified. Compared with 25 patients with CADASIL for clinical, familial, and neuroimaging features, only the following variables were significantly ( α level <0.05) different in frequency between patients with CADASIL and CADASIL-like patients: a positive family history for stroke at age ≤60 years, more frequent in patients with CADASIL, and hypertension, more frequent in CADASIL-like patients. Conclusions Our experience highlights the growing number of patients presenting with a high suspicion of a cerebral small vessel disease with an autosomal dominant pattern of inheritance and a phenotype closely similar to that of CADASIL but without NOTCH3 mutations. This group remains to be characterized from the genetic point of view. The role of other genes or NOTCH3 alterations on exons other than 2-23 or introns has to be further assessed. [ABSTRACT FROM AUTHOR]

We present the results of a semianalytical model that evolves the masses and spins of massive black holes together with the properties of their host galaxies across the cosmic history. As a consistency check, our model broadly reproduces a number of observations, e.g., the cosmic star formation history; the black hole mass, luminosity, and galaxy mass functions at low redshift; the black hole-bulge mass relation; and the morphological distribution at low redshift. For the first time in a semianalytical investigation, we relax the simplifying assumptions of perfect coherency or perfect isotropy of the gas fueling the black holes. The dynamics of gas is instead linked to the morphological properties of the host galaxies, resulting in different spin distributions for black holes hosted in different galaxy types. We compare our results with the observed sample of spin measurements obtained through broad Kα iron line fitting. The observational data disfavor both accretion along a fixed direction and isotropic fueling. Conversely, when the properties of the accretion flow are anchored to the kinematics of the host galaxy, we obtain a good match between theoretical expectations and observations. A mixture of coherent accretion and phases of activity in which the gas dynamics is similar to that of the stars in bulges (i.e., with a significant velocity dispersion superimposed to a net rotation) best describes the data, adding further evidence in support of the coevolution of massive black holes and their hosts. [ABSTRACT FROM AUTHOR]

Background and purpose Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited cerebral small vessel disease that may lead to disability and whose phenotype modulators are still unknown. Methods In the MIcrovascular LEukoencephalopathy Study ( MILES), we assessed the influence of vascular risk factors and the effect of different cognitive domains (memory, psychomotor speed and executive functions) performances on functional abilities in CADASIL in comparison with age-related leukoencephalopathy ( ARL). Results We evaluated 51 CADASIL patients (mean age 50.3 ± 13.8 years, 47.1% males) and 68 ARL patients (70.6 ± 7.4 years, 58.8% males). Considering vascular risk factors, after adjustment for age, CADASIL patients had higher mean BMI values than ARL patients. Stroke history frequency was similar in the two groups. After adjustment for age, more CADASIL patients were disabled (impaired on ≥2 items of the Instrumental Activities of Daily Living scale) in comparison with ARL patients, and CADASIL patients had worse functional performances evaluated with the Disability Assessment for Dementia ( DAD) scale. In CADASIL patients, hypertension was related to both DAD score and disability. The cognitive profile of CADASIL and ARL patients was similar, but on a stepwise linear regression analysis functional performances were mainly associated with the memory index (β = −0.418, P < 0.003) in CADASIL patients and the executive function index (β = −0.321, P = 0.028) in ARL. Conclusions This study suggests that hypertension may contribute to functional impairment in CADASIL and that memory impairment has a large influence on functional decline in contrast with that observed in a sample of subjects with ARL. [ABSTRACT FROM AUTHOR]