1,978 research outputs found
Phase diagram for non-axisymmetric plasma balls
Plasma balls and rings emerge as fluid holographic duals of black holes and
black rings in the hydrodynamic/gravity correspondence for the Scherk-Schwarz
AdS system. Recently, plasma balls spinning above a critical rotation were
found to be unstable against m-lobed perturbations. In the phase diagram of
stationary solutions the threshold of the instability signals a bifurcation to
a new phase of non-axisymmetric configurations. We find explicitly this family
of solutions and represent them in the phase diagram. We discuss the
implications of our results for the gravitational system. Rotating
non-axisymmetric black holes necessarily radiate gravitational waves. We thus
emphasize that it would be important, albeit possibly out of present reach, to
have a better understanding of the hydrodynamic description of gravitational
waves and of the gravitational interaction between two bodies. We also argue
that it might well be that a non-axisymmetric m-lobed instability is also
present in Myers-Perry black holes for rotations below the recently found
ultraspinning instability.Comment: 1+22 pages, 3 figures. v2: minor corrections and improvements,
matches published versio
Drug Release from Microspheres and Nanospheres of Poly(lactide-co-glycolide) without Sphere Separation from the Release Medium
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)A new technique using diffuse reflectance spectroscopy was developed that enables the monitoring of encapsulated drug release without particle separation from the assayed medium. Studies of chloro(5,10,15,20-tetraphenylporphyrinato)indium(III) (InTPP) release from microspheres and nanospheres of poly(lactide-co-glycolide) (PLGA) were performed using this new technique. The release of InTPP was biphasic, with an initial fast release followed by a second slower release. Mathematical models applied to the release profiles showed that the release of InTPP from the nanospheres was controlled by diffusion, which is to be expected for a substance homogeneously dispersed within the spheres. However, due to the large size distribution of the microspheres loaded with InTPP, the release profiles were irregular, hampering an adequate fit to mathematical models. Confocal analysis of microparticles showed that the InTPP appeared to be homogenously distributed within the microspheres and no preferential distribution of InTPP towards the interior or towards the surface of the spheres was observed.212214225Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Estadual de CampinasFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Alternative reconstruction after pancreaticoduodenectomy
<p>Abstract</p> <p>Background</p> <p>Pancreaticoduodenectomy is the procedure of choice for tumors of the head of the pancreas and periampulla. Despite advances in surgical technique and postoperative care, the procedure continues to carry a high morbidity rate. One of the most common morbidities is delayed gastric emptying with rates of 15%–40%. Following two prolonged cases of delayed gastric emptying, we altered our reconstruction to avoid this complication altogether. Subsequently, our patients underwent a classic pancreaticoduodenectomy with an undivided <it>Roux-en-Y </it>technique for reconstruction.</p> <p>Methods</p> <p>We reviewed the charts of our last 13 Whipple procedures evaluating them for complications, specifically delayed gastric emptying. We compared the outcomes of those patients to a control group of 15 patients who underwent the Whipple procedure with standard reconstruction.</p> <p>Results</p> <p>No instances of delayed gastric emptying occurred in patients who underwent an undivided <it>Roux-en-Y </it>technique for reconstruction. There was 1 wound infection (8%), 1 instance of pneumonia (8%), and 1 instance of bleeding from the gastrojejunal staple line (8%). There was no operative mortality.</p> <p>Conclusion</p> <p>Use of the undivided <it>Roux-en-Y </it>technique for reconstruction following the Whipple procedure may decrease the incidence of delayed gastric emptying. In addition, it has the added benefit of eliminating bile reflux gastritis. Future randomized control trials are recommended to further evaluate the efficacy of the procedure.</p
SmartEx: a case study on user profiling and adaptation in exhibition booths
An investigation into user profiling and adaptation with exhibition booth as a case study is reported. First a review of the field of exhibitions and trade fairs and a summary introduction to adaptation and profiling are given. We then introduce three criteria for the evaluation of exhibition booth: effectiveness, efficiency and affect. Effectiveness is related the amount of information collected, efficiency is a measurement of the time taken to collect the information, and affect is the perception of the experience and the mood booth visitors have during and after their visit. We have selected these criteria to assess adaptive and profiled exhibition booths, we call smart exhibition (SmartEx). The assessment is performed with an experiment with three test conditions (non-profiled/non adaptive, profiled/non-adaptive and profiled adaptive presentations). Results of the experiment are presented along discussion. While there is significant improvements of effectiveness and efficiency between the two-first test conditions, the improvement is not significant for the last test condition, for reasons explained. As for the affect, the results show that it has an under-estimated importance in people minds and that it should be addressed more carefully
Promoção da atividade física e do exercício durante a gravidez e o pós-parto. Guia para profissionais de saúde
info:eu-repo/semantics/publishedVersio
Kerr-AdS and its Near-horizon Geometry: Perturbations and the Kerr/CFT Correspondence
We investigate linear perturbations of spin-s fields in the Kerr-AdS black
hole and in its near-horizon geometry (NHEK-AdS), using the Teukolsky master
equation and the Hertz potential. In the NHEK-AdS geometry we solve the
associated angular equation numerically and the radial equation exactly. Having
these explicit solutions at hand, we search for linear mode instabilities. We
do not find any (non-)axisymmetric instabilities with outgoing boundary
conditions. This is in agreement with a recent conjecture relating the
linearized stability properties of the full geometry with those of its
near-horizon geometry. Moreover, we find that the asymptotic behaviour of the
metric perturbations in NHEK-AdS violates the fall-off conditions imposed in
the formulation of the Kerr/CFT correspondence (the only exception being the
axisymmetric sector of perturbations).Comment: 26 pages. 4 figures. v2: references added. matches published versio
Saliency detection for large-scale mesh decimation
Highly complex and dense models of 3D objects have recently become indispensable in digital industries. Mesh decimation then plays a crucial role in the production pipeline to efficiently get visually convincing yet compact expressions of complex meshes. However, the current pipeline typically does not allow artists control the decimation process, just a simplification rate. Thus a preferred approach in production settings splits the process into a first pass of saliency detection highlighting areas of greater detail, and allowing artists to iterate until satisfied before simplifying the model. We propose a novel, efficient multi-scale method to compute mesh saliency at coarse and finer scales, based on fast mesh entropy of local surface measurements. Unlike previous approaches, we ensure a robust and straightforward calculation of mesh saliency even for densely tessellated models with millions of polygons. Moreover, we introduce a new adaptive subsampling and interpolation algorithm for saliency estimation. Our implementation achieves speedups of up to three orders of magnitude over prior approaches. Experimental results showcase its resilience to problem scenarios that efficiently scales up to process multi-million vertex meshes. Our evaluation with artists in the entertainment industry also demonstrates its applicability to real use-case scenarios
Over a millon Creatine Kinase due to a heavy work-out: A case report
Rhabdomyolysis induced by exercise is a very well known entity, several cases has been reported in the literature related with strenuous activities, weight lifting, marathon running, overexertion in an untrained person, knee bends, etc. We reported an interesting case of exercise-induced rhabdomyolysis in a 25 year old Hispanic male, after resuming his regular physical activity, with the highest creatine kinase described in the literature, successfully treated with aggressive hydration only and no complications
The remnants of galaxy formation from a panoramic survey of the region around M31
In hierarchical cosmological models, galaxies grow in mass through the
continual accretion of smaller ones. The tidal disruption of these systems is
expected to result in loosely bound stars surrounding the galaxy, at distances
that reach times the radius of the central disk. The number,
luminosity and morphology of the relics of this process provide significant
clues to galaxy formation history, but obtaining a comprehensive survey of
these components is difficult because of their intrinsic faintness and vast
extent. Here we report a panoramic survey of the Andromeda galaxy (M31). We
detect stars and coherent structures that are almost certainly remnants of
dwarf galaxies destroyed by the tidal field of M31. An improved census of their
surviving counterparts implies that three-quarters of M31's satellites brighter
than await discovery. The brightest companion, Triangulum (M33), is
surrounded by a stellar structure that provides persuasive evidence for a
recent encounter with M31. This panorama of galaxy structure directly confirms
the basic tenets of the hierarchical galaxy formation model and reveals the
shared history of M31 and M33 in the unceasing build-up of galaxies.Comment: Published in Nature. Supplementary movie available at
https://www.astrosci.ca/users/alan/PANDAS/Latest%20news%3A%20movie%20of%20orbit.htm
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