Predictions of Neutrino Mixing Angles in a T'Model

Flavor symmetry ($T^{'} \times Z_2$) where $T^{'}$ is the binary tetrahedral group predicts for neutrino mixing angles $\theta_{13} = \sqrt{2} (\frac{\pi}{4} - \theta_{23})$ and, with one phenomenological input, provides upper and lower bounds on both $\theta_{13}$ and $\theta_{23}$. The predictions arise from the deviation of the Cabibbo angle $\Theta_{12}$ from its lowest-order value $\tan 2\Theta_{12} = (\sqrt{2})/3$ and from the $T^{'}$ mechanism which relates mixing of $(\nu_{\tau}, \nu_{\mu}, \nu_e)$ neutrinos to mixing of $(s, d)$ quarks.Comment: Typos. Reference adde

CKM and Tri-bimaximal MNS Matrices in a SU(5) x (d)T Model

We propose a model based on SU(5) x {}^{(d)}T which successfully gives rise to near tri-bimaximal leptonic mixing as well as realistic CKM matrix elements for the quarks. The Georgi-Jarlskog relations for three generations are also obtained. Due to the {}^{(d)}T transformation property of the matter fields, the b-quark mass can be generated only when the {}^{(d)}T symmetry is broken, giving a dynamical origin for the hierarchy between m_{b} and m_{t}. There are only nine operators allowed in the Yukawa sector up to at least mass dimension seven due to an additional Z_{12} x Z'_{12} symmetry, which also forbids, up to some high orders, operators that lead to proton decay. The resulting model has a total of nine parameters in the charged fermion and neutrino sectors, and hence is very predictive. In addition to the prediction for \theta_{13} \simeq \theta_{c}/3 \sqrt{2}, the model gives rise to a sum rule, \tan^{2}\theta_{\odot} \simeq \tan^{2} \theta_{\odot, \mathrm{TBM}} - {1/2} \theta_{c} \cos\beta, which is a consequence of the Georgi-Jarlskog relations in the quark sector. This deviation could account for the difference between the experimental best fit value for the solar mixing angle and the value predicted by the tri-bimaximal mixing matrix.Comment: 11 pages; v2: additional references added; minor modifications made; conclusion unchanged; v3: version to appear in Phys. Lett.

Assessing Variability in End-of-Life Intensity of Care After Out-of-Hospital Cardiac Arrest

Out of hospital cardiac arrest (OHCA) affects over 300,000 Americans per year.1 Many factors affect the outcomes and overall OHCA survival in a community; some of these include an individual’s characteristics such as age, co-morbid conditions, availability of an AED on scene, time to CPR, and the characteristics of the hospital they are treated at.1,2 Directly following resuscitation from cardiac arrest, the individual is at risk of developing numerous problems caused by sequelae of ischemic injury sustained during the arrest. The national average rate of survival to discharge is only 10%.2,3 Many of these factors are modifiable and provide an opportunity to improve outcomes. In our project, we focus on lifesustaining procedures administered by hospitals upon receiving and admitting individuals experiencing OHCA. We used previously validated measures as defined by Barnato et al as “life sustaining end of life (EOL) measures”:4 • Intubation and mechanical ventilation • Tracheostomy • Gastrostomy tube insertion • Hemodialysis • Enteral/parenteral nutrition • CPRhttps://jdc.jefferson.edu/cwicposters/1035/thumbnail.jp

Bose and Fermi gases in the early universe with self-gravitational effect

We study the self-gravitational effect on the equation of state (EoS) of Bose and Fermi gases in thermal equilibrium at the end of reheating, the period after quark-hadron transition and before Big Bang Nucleosynthesis (BBN). After introducing new grand canonical partition functions based on the work of Uhlenbeck and Gropper, we notice some interesting features of the newly developed EoSs with distinct behaviors of relativistic and non-relativistic gases under self-gravity. The usual negligence of the self-gravitational effect when solving the background expansion of the early universe is justified with numerical results, showing the magnitude of the self-gravitational modification of the state constant to be less than $O(10^{-78})$. This helps us to clarify the background thermal evolution of the primordial patch. Such clarification is crucial in testing gravity theories, evaluating inflation models and determining element abundances in BBN.Comment: 10 pages, 2 figures, to appear in PR

Tri-bimaximal Neutrino Mixing and Quark Masses from a Discrete Flavour Symmetry

We build a supersymmetric model of quark and lepton masses based on the discrete flavour symmetry group T', the double covering of A_4. In the lepton sector our model is practically indistinguishable from recent models based on A_4 and, in particular, it predicts a nearly tri-bimaximal mixing, in good agreement with present data. In the quark sector a realistic pattern of masses and mixing angles is obtained by exploiting the doublet representations of T', not available in A_4. To this purpose, the flavour symmetry T' should be broken spontaneously along appropriate directions in flavour space. In this paper we fully discuss the related vacuum alignment problem, both at the leading order and by accounting for small effects coming from higher-order corrections. As a result we get the relations: \sqrt{m_d/m_s}\approx |V_{us}| and \sqrt{m_d/m_s}\approx |V_{td}/V_{ts}|.Comment: 27 pages, 1 figure; minor correction

Electric field-tunable layer polarization in graphene/boron nitride twisted quadrilayer superlattices

The recently observed unconventional ferroelectricity in AB bilayer graphene sandwiched by hexagonal Boron Nitride (hBN) presents a new platform to manipulate correlated phases in multilayered van der Waals heterostructures. We present a low-energy continuum model for AB bilayer graphene encapsulated by the top and bottom layers of either hBN or graphene, with two independent twist angles. For the graphene/hBN heterostructures, we show that twist angle asymmetry leads to a layer polarization of the valence and conduction bands. We also show that an out-of-plane displacement field not only tunes the layer polarization but also flattens the low-energy bands. We extend the model to show that the electronic structures of quadrilayer graphene heterostructure consisting of AB bilayer graphene encapsulated by the top and bottom graphene layers can similarly be tuned by an external electric field

Signatures of a Pressure-Induced Topological Quantum Phase Transition in BiTeI

We report the observation of two signatures of a pressure-induced topological quantum phase transition in the polar semiconductor BiTeI using x-ray powder diffraction and infrared spectroscopy. The x-ray data confirm that BiTeI remains in its ambient-pressure structure up to 8 GPa. The lattice parameter ratio c/a shows a minimum between 2.0-2.9 GPa, indicating an enhanced c-axis bonding through pz band crossing as expected during the transition. Over the same pressure range, the infrared spectra reveal a maximum in the optical spectral weight of the charge carriers, reflecting the closing and reopening of the semiconducting band gap. Both of these features are characteristics of a topological quantum phase transition, and are consistent with a recent theoretical proposal.Comment: revised final versio

I-LEEP Newsletter Volume 1, Issue 3

https://digitalcommons.lasalle.edu/ileep_newsletter/1002/thumbnail.jp

Deep subcutaneous application of poly-L-lactic acid as a filler for facial lipoatrophy in HIV-infected patients

Introduction: Facial lipoatrophy is a crucial problem of HIV-infected patients undergoing highly active antiretroviral therapy (HAART). Poly-L-lactic acid (PLA), provided as New-Fill(R)/Sculptra(TM), is known as one possible treatment option. In 2004 PLA was approved by the FDA as Sculptra(TM) for the treatment of lipoatrophy of the face in HIV-infected patients. While the first trials demonstrated relevant efficacy, this was to some extent linked to unwanted effects. As the depth of injection was considered relevant in this context, the application modalities of the preparation were changed. The preparation was to be injected more deeply into subcutaneous tissue, after increased dilution. Material and Methods: To test this approach we performed a pilot study following the new recommendations in 14 patients. Results: While the efficacy turned out to be about the same, tolerability was markedly improved. The increase in facial dermal thickness was particularly obvious in those patients who had suffered from lipoatrophy for a comparatively small period of time. Conclusion: With the new recommendations to dilute PLA powder and to inject it into the deeper subcutaneous tissue nodule formation is a minor problem. However, good treatment results can only be achieved if lipoatrophy is not too intense; treatment intervals should be about 2 - 3 weeks. Copyright (C) 2005 S. Karger AG, Basel

ARC Newsletter Volume 1, Issue 2

https://digitalcommons.lasalle.edu/arc_newsletter/1001/thumbnail.jp