Late-time vacuum phase transitions: Connecting sub-eV scale physics with cosmological structure formation

We show that a particular class of postrecombination phase transitions in the vacuum can lead to localized overdense regions on relatively small scales, roughly 10^6 to 10^10 M_sun, potentially interesting for the origin of large black hole seeds and for dwarf galaxy evolution. Our study suggests that this mechanism could operate over a range of conditions which are consistent with current cosmological and laboratory bounds. One byproduct of phase transition bubble-wall decay may be extra radiation energy density. This could provide an avenue for constraint, but it could also help reconcile the discordant values of the present Hubble parameter (H_0) and sigma_8 obtained by cosmic microwave background (CMB) fits and direct observational estimates. We also suggest ways in which future probes, including CMB considerations (e.g., early dark energy limits), 21-cm observations, and gravitational radiation limits, could provide more stringent constraints on this mechanism and the sub-eV scale beyond-standard-model physics, perhaps in the neutrino sector, on which it could be based. Late phase transitions associated with sterile neutrino mass and mixing may provide a way to reconcile cosmological limits and laboratory data, should a future disagreement arise.Comment: 17 pages, 18 figures. v2: includes additional references and minor corrections/clarifications. v3: includes additional text, figures, and references (matches published version

Neutrino Flavor Evolution in Neutron Star Mergers

We examine the flavor evolution of neutrinos emitted from the disk-like remnant (hereafter called \lq\lq neutrino disk\rq\rq) of a binary neutron star (BNS) merger. We specifically follow the neutrinos emitted from the center of the disk, along the polar axis perpendicular to the equatorial plane. We carried out two-flavor simulations using a variety of different possible initial neutrino luminosities and energy spectra, and for comparison, three-flavor simulations in specific cases. In all simulations, the normal neutrino mass hierarchy was used. The flavor evolution was found to be highly dependent on the initial neutrino luminosities and energy spectra; in particular, we found two broad classes of results depending on the sign of the initial net electron neutrino lepton number (i.e., the number of neutrinos minus the number of antineutrinos). In the antineutrino dominated case, we found that the Matter-Neutrino Resonance (MNR) effect dominates, consistent with previous results, whereas in the neutrino dominated case, a bipolar spectral swap develops. The neutrino dominated conditions required for this latter result have been realized, e.g, in a BNS merger simulation that employs the \lq\lq DD2\rq\rq\ equation of state for neutron star matter[Phys. Rev. D 93, 044019 (2016)]. For this case, in addition to the swap at low energies, a collective Mikheyev-Smirnov-Wolfenstein (MSW) mechanism generates a high-energy electron neutrino tail. The enhanced population of high-energy electron neutrinos in this scenario could have implications for the prospects of $r$-process nucleosynthesis in the material ejected outside the plane of the neutrino disk.Comment: Version published in Physical Review D. 22 pages, 16 figures, 9 tables. For movies see Ancillary files in version

Ablation Surgery for Atrial Fibrillation: "Freeze it or Buzz it; Just do it and Cure it"

Patients in normal sinus rhythm have lesser stroke rate, better functional class and quality of life than those in atrial fibrillation. Adding a surgical procedure to cure atrial fibrillation in patients needing correction of structural heart disease has been shown to be a safe option, which benefits the majority in restoration of sinus rhythm. Age is no bar to implement this option. The same does not hold true for lone atrial fibrillation. The affirm trial has shown that there is need for improved treatment strategies for patients in atrial fibrillation, although young patients were not represented in sizable proportion. There is need to develop curative treatment for patients with lone atrial fibrillation. And there are technological advances in the form of ablative energy sources and hardware for applying these with minimal invasion. “Between tomorrow’s dream and yesterday’s regret is today’s opportunity”. Let’s make the best of it

Unified model of phrasal and sentential evidence for information extraction

Journal ArticleInformation Extraction (IE) systems that extract role fillers for events typically look at the local context surrounding a phrase when deciding whether to extract it. Often, however, role fillers occur in clauses that are not directly linked to an event word. We present a new model for event extraction that jointly considers both the local context around a phrase along with the wider sentential context in a probabilistic framework. Our approach uses a sentential event recognizer and a plausible role-filler recognizer that is conditioned on event sentences. We evaluate our system on two IE data sets and show that our model performs well in comparison to existing IE systems that rely on local phrasal context

Feature subsumption for opinion analysis

Journal ArticleLexical features are key to many approaches to sentiment analysis and opinion detection. A variety of representations have been used, including single words, multi-word Ngrams, phrases, and lexicosyntactic patterns. In this paper, we use a subsumption hierarchy to formally define different types of lexical features and their relationship to one another, both in terms of representational coverage and performance. We use the subsumption hierarchy in two ways: (1) as an analytic tool to automatically identify complex features that outperform simpler features, and (2) to reduce a feature set by removing unnecessary features. We show that reducing the feature set improves performance on three opinion classification tasks, especially when combined with traditional feature selection

Effective information extraction with semantic affinity patterns and relevant regions

Journal ArticleWe present an information extraction system that decouples the tasks of finding relevant regions of text and applying extraction patterns. We create a self-trained relevant sentence classifier to identify relevant regions, and use a semantic affinity measure to automatically learn domain-relevant extraction patterns. We then distinguish primary patterns from secondary patterns and apply the patterns selectively in the relevant regions. The resulting IE system achieves good performance on the MUC-4 terrorism corpus and ProMed disease outbreak stories. This approach requires only a few seed extraction patterns and a collection of relevant and irrelevant documents for training

Multidirectional ECG Coherent Optimal Timing of Defibrillation Shocks

A method for of delivering a defibrillation shock to a heart at an optimal time to stop ventricular fibrillation which involves obtaining an electrocardiogram of a heart in at least two directions, determining a time-coherency of the electrocardiogram based upon each of the at least two directions, and computing a tracking function from the time-coherency. An optimal time to apply a defibrillation shock to the heart is determined by locating a local maximum on the tracking function. The method utilizes spacia characteristics of the ventricular fibrillation. The method can be incorporated into implantable cardioverter defibrillators utilizing existing hardware technology

Cardiac Valvular Inflammatory Pseudotumor

Inflammatory pseudotumors are quasineoplastic lesions that occur in the lungs as well as other extrapulmonary sites. The heart is an uncommon site of origin. We report a valvular pseudotumor that produced chronic mitral and aortic regurgitation in an elderly woman