Carotid cavernous fistulas (CCF) can be effectively treated by using different therapeutic alternatives such as detachable balloons and detachable coils, alone or in combination with ...N-butyl-2-cyanoacrylate (n-BCA) or Onyx. Stents have also been used in an attempt to improve preservation of the parent artery while still occluding the fistula. We present our experience using balloon-expandable covered stents to treat CCF, focusing on arterial wall reconstruction. To our knowledge, this is the first series with midterm follow-up between 3 months and 3.5 years.
From the 46 CCF treated at our institution between November 1998 and September 2006, a total of 7 posttraumatic direct CCF were treated using polytetrafluoroethylene (PTFE)-covered stents between April 2003 and September 2006. Five were treated with covered stents alone. One patient with transection of the internal carotid artery (ICA) first underwent bare stent placement to provide support for the covered stent. One patient had to be treated with coils and n-BCA.
Control angiograms obtained in the 7 patients demonstrated occlusion of the fistula and preservation of the ICA in all cases. There was no mortality and no immediate postprocedural morbidity. There was 1 case of morbidity identified at 1-month follow-up with asymptomatic occlusion of the ICA; the other 6 patients had angiographic follow-up between 3 and 42 months (mean, 18.4 months), with persistent occlusion of the fistulas, patent stent grafts, and no significant intimal hyperplasia.
PTFE-covered stents are evolving as a promising intracranial therapeutic alternative to treat CCF and preserve the parent artery by reconstructing the arterial wall. They should be considered in patients in whom fistulas cannot be successfully occluded with detachable balloons or detachable coils. More investigation is required to further develop their specifications and indications.
Trait mindfulness appears to be related to lower levels of negative affective symptoms, but it remains uncertain which facets of mindfulness are most important in this relationship. Accordingly, the ...present meta-analysis examined studies reporting correlations between affective symptoms and trait mindfulness as assessed by the Five Facet Mindfulness Questionnaire. A comprehensive search yielded 148 eligible studies, comprising 157 distinct samples and 44,075 participants. The weighted mean correlation for affective symptoms and overall trait mindfulness was r = −0.53. Among mindfulness facets, Nonjudge (r = −0.48) and Act with Awareness (r = −0.47) demonstrated the largest correlations, followed by Nonreact (r = −0.33) and Describe (r = −0.29). Observe was not significantly correlated with affective symptoms. No significant differences in the strength of correlations were found between anxiety, depression and posttraumatic stress disorder (PTSD) symptoms, though symptoms of generalized anxiety disorder exhibited a weaker negative relationship with the Describe facet compared to PTSD symptoms. Describe also showed a stronger relationship with affective symptoms in Eastern samples compared to Western samples, whereas Western samples had a stronger relationship with Nonjudge. These results provide insight into the nature of the association between trait mindfulness and negative affect.
•Higher trait mindfulness is associated with fewer negative affective symptoms.•Relationships with symptoms vary across different mindfulness facets.•Nonjudging and Acting with Awareness show the strongest correlations.•Observing is not meaningfully correlated with symptoms in non-meditators.•Relationships were mostly consistent across symptom type (e.g. anxiety, depression).
We report the discovery of a substantial stellar overdensity in the periphery of the Large Magellanic Cloud (LMC), found using public imaging from the first year of the Dark Energy Survey. The ...structure appears to emanate from the edge of the outer LMC disc at a radius ≈13
$_{.}^{\circ}$
5 due north of its centre, and stretches more than 10 kpc towards the east. It is roughly 1.5 kpc wide and has an integrated V-band luminosity of at least M
V
= −7.4. The stellar populations in the feature are indistinguishable from those in the outer LMC disc. We attempt to quantify the geometry of the outer disc using simple planar models, and find that only a disc with mild intrinsic ellipticity can simultaneously explain the observed stellar density on the sky and the azimuthal line-of-sight distance profile. We also see possible non-planar behaviour in the outer disc that may reflect a warp and/or flare, as well as deviations that resemble a ring-like structure between
${\sim }9^\circ \hbox{ and }12^\circ$
from the LMC centre. Based on all these observations, we conclude that our remote, stream-like feature is likely comprised of material that has been stripped from the outskirts of the LMC disc, although we cannot rule out that it represents a transient overdensity in the disc itself. We conduct a simple N-body simulation to show that either type of structure could plausibly arise due to the tidal force of the Milky Way; however, we also recognize that a recent close interaction between the LMC and the Small Magellanic Cloud may be the source of the stripping or perturbation. Finally, we observe evidence for extremely diffuse LMC populations extending to radii of ∼18.5 kpc in the disc plane (
${\approx } 20^\circ$
on the sky), corroborating previous spectroscopic detections at comparable distances.
ABSTRACT
We explore the chemodynamical properties of a sample of barred galaxies in the Auriga magnetohydrodynamical cosmological zoom-in simulations, which form boxy/peanut (b/p) bulges, and compare ...these to the Milky Way (MW). We show that the Auriga galaxies which best reproduce the chemodynamical properties of stellar populations in the MW bulge have quiescent merger histories since redshift z ∼ 3.5: their last major merger occurs at $t_{\rm lookback}\gt 12\, \rm Gyr$, while subsequent mergers have a stellar mass ratio of ≤1:20, suggesting an upper limit of a few per cent for the mass ratio of the recently proposed Gaia Sausage/Enceladus merger. These Auriga MW-analogues have a negligible fraction of ex-situ stars in the b/p region ($\lt 1{{\ \rm per\ cent}}$), with flattened, thick disc-like metal-poor stellar populations. The average fraction of ex-situ stars in the central regions of all Auriga galaxies with b/p’s is 3 per cent – significantly lower than in those which do not host a b/p or a bar. While the central regions of these barred galaxies contain the oldest populations, they also have stars younger than 5 Gyr (>30 per cent) and exhibit X-shaped age and abundance distributions. Examining the discs in our sample, we find that in some cases a star-forming ring forms around the bar, which alters the metallicity of the inner regions of the galaxy. Further out in the disc, bar-induced resonances lead to metal-rich ridges in the Vϕ − r plane – the longest of which is due to the Outer Lindblad Resonance. Our results suggest the Milky Way has an uncommonly quiet merger history, which leads to an essentially in-situ bulge, and highlight the significant effects the bar can have on the surrounding disc.
In the notch stress intensity approach to the fatigue assessment of welded joints, the weld toe is modelled as a sharp V-notch,
ρ
=
0, and local stress distributions in plane configurations are given ...on the basis of the relevant mode I and mode II notch stress intensity factors (NSIFs). The local strain energy density over a circular sector surrounding the point of singularity can be easily calculated as soon as the NSIFs are known. Whilst the NSIF evaluation needs very fine meshes in the vicinity of the points of singularity, which is a drawback of the approach in the presence of complex geometries, the mean value of the elastic SED on the control volume can be accurately determined by using relatively coarse meshes. This fact is demonstrated here by using a number of FE models with very different mesh refinements. Both bi-dimensional and three-dimensional welded details are considered showing degree of accuracy and limits of applicability of the method. Thanks to the SED use, the degree of refinement of FE models is not so different from that usually used to determine the ‘hot-spot stress’ according to the structural stress approach.
We have evaluated the possibility that the action of voluntary exercise on the regulation of brain‐derived neurotrophic factor (BDNF), a molecule important for rat hippocampal learning, could involve ...mechanisms of epigenetic regulation. We focused the studies on the Bdnf promoter IV, as this region is highly responsive to neuronal activity. We have found that exercise stimulates DNA demethylation in Bdnf promoter IV, and elevates levels of activated methyl‐CpG‐binding protein 2, as well as BDNF mRNA and protein in the rat hippocampus. Chromatin immunoprecipitation assay showed that exercise increases acetylation of histone H3, and protein assessment showed that exercise elevates the ratio of acetylated : total for histone H3 but had no effects on histone H4 levels. Exercise also reduces levels of the histone deacetylase 5 mRNA and protein implicated in the regulation of the Bdnf gene N.M. Tsankova et al. (2006)Nat. Neurosci., 9, 519–525, but did not affect histone deacetylase 9. Exercise elevated the phosphorylated forms of calcium/calmodulin‐dependent protein kinase II and cAMP response element binding protein, implicated in the pathways by which neural activity influences the epigenetic regulation of gene transcription, i.e. Bdnf. These results showing the influence of exercise on the remodeling of chromatin containing the Bdnf gene emphasize the importance of exercise on the control of gene transcription in the context of brain function and plasticity. Reported information about the impact of a behavior, inherently involved in the daily human routine, on the epigenome opens exciting new directions and therapeutic opportunities in the war against neurological and psychiatric disorders.
We present the results of our survey of 1612-MHz circumstellar OH maser emission from asymptotic giant branch (AGB) stars and red supergiants (RSGs) in the Large Magellanic Cloud (LMC). We have ...discovered four new circumstellar maser sources in the LMC, and increased the number of reliable wind speeds from infrared (IR) stars in the LMC from 5 to 13. Using our new wind speeds, as well as those from Galactic sources, we have derived an updated relation for dust-driven winds: ... We compare the subsolar metallicity LMC OH/IR stars with carefully selected samples of more metal-rich OH/IR stars, also at known distances, in the Galactic Centre and Galactic bulge. We derive pulsation periods for eight of the bulge stars for the first time by using near-IR photometry from the Vista Variables in the Via Lactea survey. We have modelled our LMC OH/IR stars and developed an empirical method of deriving gas-to-dust ratios and mass-loss rates by scaling the models to the results from maser profiles. We have done this also for samples in the Galactic Centre and bulge and derived a new mass-loss prescription which includes luminosity, pulsation period, and gas-to-dust ratio ... The tightest correlation is found between mass-loss rate and luminosity. We find that the gas-to-dust ratio has little effect on the mass-loss of oxygen-rich AGB stars and RSGs within the Galaxy and the LMC. This suggests that the mass-loss of oxygen-rich AGB stars and RSGs is (nearly) independent of metallicity between a half and twice solar. (ProQuest: ... denotes formulae/symbols omitted.)
In the nonadiabatic dynamics across a quantum phase transition, the Kibble-Zurek mechanism predicts that the formation of topological defects is suppressed as a universal power law with the quench ...time. In inhomogeneous systems, the critical point is reached locally and causality reduces the effective system size for defect formation to regions where the velocity of the critical front is slower than the sound velocity, favoring adiabatic dynamics. The reduced density of excitations exhibits a much steeper dependence on the quench rate and is also described by a universal power law that we demonstrated in a quantum Ising chain.
Ambrosia beetles of the
(Eichhoff, 1868) species complex are emerging tree pests, responsible for significant damage to orchards and ecosystems around the world. The species complex comprises seven ...described species, all of which are nearly identical. Given that the morphology-defined species boundaries have been ambiguous, historically, there has been much disagreement on species validity, which was compounded by the presumed loss of the type series of
. The species complex was recently reviewed using morphometrics to associate the type specimens to the clades delineated with molecular data under the assumption of the lost type series. We rediscovered a syntype of
, and reevaluated the species in the complex using morphometrics. We propose the following taxonomic changes to the species complex:
(=
(Schedl, 1951); =
(Schedl, 1942))
);
(Eggers, 1923) (=
.
(Schedl, 1951)
);
(Gomez and Hulcr, 2018) and
(Schedl, 1951)
. These taxonomic changes shift the species name associated with the widely used common names for two taxa, namely:
should be used for the "Polyphagous Shot Hole Borer", and
for the "Tea Shot Hole Borer clade a". A lectotype is designated for
in order to stabilize the use of the name.
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