Invisible decays of ultra-high energy neutrinos

Gamma-ray bursts (GRBs) are expected to provide a source of ultra high energy cosmic rays, accompanied with potentially detectable neutrinos at neutrino telescopes. Recently, IceCube has set an upper bound on this neutrino flux well below theoretical expectation. We investigate whether this mismatch between expectation and observation can be due to neutrino decay. We demosntrate the phenomenological consistency and theoretical plausibility of the neutrino decay hypothesis. A potential implication is the observability of majoron-emitting neutrinoless double beta decay.Comment: 11 pages, 3 figures. To appear in Frontiers High Energy Physic

Factor associated with student permanence at the university of Sonora: confirmatory factor analysis.

El constructo de permanencia ha sido abordado a través de modelos que permiten explicar las trayectorias escolares. El presente documento tuvo como objetivo validar la escala en estudiantes universitarios con un Análisis Factorial Confirmatorio para verificar los supuestos en el modelo de permanencia, teniendo confiabilidad de Alfa de Cronbach de .91. Se obtuvieron dos modelos, el modelo de cuatro factores de segundo orden con el mejor ajuste, así como el modelo de covarianzas de primer orden entre factores. Se discute que los hallazgos se encuentran en sintonía con lo establecido en la teoría y se sugiere seguir probando los modelos

A new neutrino mass sum rule from inverse seesaw

A class of discrete flavor-symmetry-based models predicts constrained neutrino mass matrix schemes that lead to specific neutrino mass sum-rules (MSR). One of these implies in a lower bound on the effective neutrinoless double beta mass parameter, even for normal hierarchy neutrinos. Here we propose a new model based on the S4 flavor symmetry that leads to the new neutrino mass sum-rule and discuss how to generate a nonzero value for the reactor mixing angle indicated by recent experiments, and the resulting correlation with the solar mixing angle.Comment: 14 pages, 4 figure

Systematic classification of two-loop realizations of the Weinberg operator

We systematically analyze the d = 5 Weinberg operator at 2-loop order. Using a diagrammatic approach, we identify two different interesting categories of neutrino mass models: (i) Genuine 2-loop models for which both, tree-level and 1-loop contributions, are guaranteed to be absent. And (ii) finite 2-loop diagrams, which correspond to the 1-loop generation of some particular vertex appearing in a given 1-loop neutrino mass model, thus being effectively 2-loop. From the large list of all possible 2-loop diagrams, the vast majority are infinite corrections to lower order neutrino mass models and only a moderately small number of diagrams fall into these two interesting classes. Moreover, all diagrams in class (i) are just variations of three basic diagrams, with examples discussed in the literature before. Similarly, we also show that class (ii) diagrams consists of only variations of these three plus two more basic diagrams. Finally, we show how our results can be consistently and readily used in order to construct two-loop neutrino mass models

From “My Block” to “Born on the Rez”: A Linguistic Analysis of Lyrics by 2PAC, Frank Waln, Litefoot, Nataanii Means, and Night Shield

The lack of consistent wide-spread media coverage of recent events in North America involving violence against Native Americans and African Americans in the U.S., missing and murdered indigenous women, led the authors to a thoughtful discussion about the similar and parallel issues shared by our people. Although the deaths of Michael Brown (August 9, 2014, Ferguson, MO), Eric Garner (July 17, 2014, NY), and Sandra Bland (July 13, 2015, TX) were nationally covered news events; the deaths of Misty Upham, Blackfeet (October 5, 2014, WA); Native American activist Rexdale Henry, Choctaw (July 14, 2015, MS), and Christina Tahhahwah, Comanche (November 13, 2014, OK), appear to have been covered locally, and shared from far fewer, predominantly Native, social media sources, if at all. The researchers undertook a project to see if Native American rappers were rapping about what went on in their communities, on reservations and pueblos, 20 years after Shakur’s death. The researchers will share their experience identifying Native American lyricists/musicians, creating a dataset from commercially available rap music, selecting digital humanities software, and analyzing the data

Developing a LIWC Dictionary: The lyrical poetry of 2PAC, Frank Waln, Litefoot, and Nataanii Means

The researchers developed a dictionary, DKL-MN2016, to use the LIWC (http://liwc.wpengine.com/) software to analyze the lyrics of 4 activist, rapper, hiphop artists who are men of color, to answer two research questions: Do Native American male rappers address socioeconomic issues in their lyrics? and How does the lyrical content of Native American male rappers compare Tupac Shakur’s lyrical content written before 1996

Non-diagonal charged lepton mass matrix and non-zero θ13\theta_{13}

Assuming that the neutrino mass matrix is diagonalized by the tribimaximal mixing matrix, we explore the textures for the charged lepton mass matrix that render an $U_{PMNS}$ lepton mixing matrix consistent with data. In particular we are interested in finding the textures with the maximum number of zeros. We explore the cases of real matrices with three and four zeros and find that only ten matrices with three zeros provide solutions in agreement with data. We present the successful Yukawa textures including the relative sizes of their non-zero entries as well as some new and interesting relations among the entries of these textures in terms of the charged lepton masses. We also show that these relations can be obtained directly from a parametrization of the charged lepton mixing matrix $U_l$.Comment: 16 pages, two figures. A parametrization of the mixing matrix $U_l$ was introduced to explain observed patterns in textures. References adde

Inhibition of the Ubc9 E2 SUMO-conjugating enzyme-CRMP2 interaction decreases NaV1.7 currents and reverses experimental neuropathic pain

We previously reported that destruction of the small ubiquitin-like modifier (SUMO) modification site in the axonal collapsin response mediator protein 2 (CRMP2) was sufficient to selectively decrease trafficking of the voltage-gated sodium channel NaV1.7 and reverse neuropathic pain. Here, we further interrogate the biophysical nature of the interaction between CRMP2 and the SUMOylation machinery, and test the hypothesis that a rationally designed CRMP2 SUMOylation motif (CSM) peptide can interrupt E2 SUMO-conjugating enzyme Ubc9-dependent modification of CRMP2 leading to a similar suppression of NaV1.7 currents. Microscale thermophoresis and amplified luminescent proximity homogeneous alpha assay revealed a low micromolar binding affinity between CRMP2 and Ubc9. A heptamer peptide harboring CRMP2's SUMO motif, also bound with similar affinity to Ubc9, disrupted the CRMP2-Ubc9 interaction in a concentration-dependent manner. Importantly, incubation of a tat-conjugated cell-penetrating peptide (t-CSM) decreased sodium currents, predominantly NaV1.7, in a model neuronal cell line. Dialysis of t-CSM peptide reduced CRMP2 SUMOylation and blocked surface trafficking of NaV1.7 in rat sensory neurons. Fluorescence dye-based imaging in rat sensory neurons demonstrated inhibition of sodium influx in the presence of t-CSM peptide; by contrast, calcium influx was unaffected. Finally, t-CSM effectively reversed persistent mechanical and thermal hypersensitivity induced by a spinal nerve injury, a model of neuropathic pain. Structural modeling has now identified a pocket-harboring CRMP2's SUMOylation motif that, when targeted through computational screening of ligands/molecules, is expected to identify small molecules that will biochemically and functionally target CRMP2's SUMOylation to reduce NaV1.7 currents and reverse neuropathic pain

Neutrino-less Double Beta Decay and Particle Physics

We review the particle physics aspects of neutrino-less double beta decay. This process can be mediated by light massive Majorana neutrinos (standard interpretation) or by something else (non-standard interpretations). The physics potential of both interpretations is summarized and the consequences of future measurements or improved limits on the half-life of neutrino-less double beta decay are discussed. We try to cover all proposed alternative realizations of the decay, including light sterile neutrinos, supersymmetric or left-right symmetric theories, Majorons, and other exotic possibilities. Ways to distinguish the mechanisms from one another are discussed. Experimental and nuclear physics aspects are also briefly touched, alternative processes to double beta decay are discussed, and an extensive list of references is provided.Comment: 96 pages, 38 figures. Published versio

Accidental stability of dark matter

We propose that dark matter is stable as a consequence of an accidental Z2 that results from a flavour-symmetry group which is the double-cover group of the symmetry group of one of the regular geometric solids. Although model-dependent, the phenomenology resembles that of a generic Higgs portal dark matter scheme.Comment: 12 pages, final version, published in JHE