10,677 research outputs found
Long-range Heisenberg models in quasi-periodically driven crystals of trapped ions
We introduce a theoretical scheme for the analog quantum simulation of
long-range XYZ models using current trapped-ion technology. In order to achieve
fully-tunable Heisenberg-type interactions, our proposal requires a
state-dependent dipole force along a single vibrational axis, together with a
combination of standard resonant and detuned carrier drivings. We discuss how
this quantum simulator could explore the effect of long-range interactions on
the phase diagram by combining an adiabatic protocol with the quasi-periodic
drivings and test the validity of our scheme numerically. At the isotropic
Heisenberg point, we show that the long-range Hamiltonian can be mapped onto a
non-linear sigma model with a topological term that is responsible for its
low-energy properties, and we benchmark our predictions with
Matrix-Product-State numerical simulations.Comment: closer to published versio
Effect of the Ketogenic Diet on Behavioral Symptoms of Autism in the Poly(IC) Mouse Model
Autism spectrum disorder (ASD) is a neurological disorder characterized by decreased sociability, deficits in communication, and restricted and repetitive behaviors. The ketogenic diet (KD), a high-fat, low-carbohydrate, and moderate-protein diet has been shown to improve these three behavioral symptoms in the BTBR mouse model of autism. However, further research is required to strengthen the body of knowledge surrounding the potential of KD as diet therapy for autism. Epidemiological observations have shown that maternal immune activation (MIA) during pregnancy increases the risk of autism in offspring. Based on these observations, the polyinosinic:polycytidylic acid (poly(IC)) mouse model was developed as an animal model to study autism. Poly(IC) is a synthetic analog of double stranded RNA and acts as a viral mimic. It is injected into a pregnant dam, activating an immune response without causing an infection. The offspring of this protocol are the poly(IC) MIA mouse model. They have been shown to have the autistic symptoms of deficits in sociability and communication as well as increased repetitive behaviors. In this study, pregnant dams were injected with poly(IC) or the saline vehicle during the late first trimester. The offspring were separated into control and test groups. At 5 weeks of age, the test group was placed on a 6:1 fat:(carbohydrates + protein) KD while the control groups remained on standard chow. After three weeks on the diet, we assessed sociability, repetitive behavior, and communication. Our results showed that KD reversed increased self-grooming in poly(IC) mice. Results did not indicate autistic-like behavior in our poly(IC) mice for social contact, sociability, grooming during the 3-chamber test, or repetitive behavior in the marble-burying test. However, KD increased social contact in poly(IC) mice. It also increased sociability and decreased 3-chamber grooming in poly(IC) males. Poly(IC) mice did not have a deficit in the social transmission of food preference task, a previously unused assessment of the poly(IC) mouse model. While our study did not succeed in replicating several autistic behaviors in the poly(IC) mouse model, KD had influence on behavior in multiple measures, increasing sociability and decreasing grooming. This suggests that KD may be an effective diet therapy for autism
COMPARING THE JOB SATISFACTION OF VIRTUAL SCHOOL EDUCATORS TO THAT OF TRADITIONAL EDUCATORS
Virtual education in the K-12 environment is a growing field in the education industry. Not only does virtual education provide new opportunities for students, it also changes how teachers work in the industry and how they perceive the job satisfaction. Using the Teacher Job Satisfaction Questionnaire (TJSQ), this study compares perceived job satisfaction of virtual educators to that of traditional educators in the K-12 environment. Data collected from 112 educators suggested that both virtual and traditional educators were satisfied with their jobs. When teachers in both environments were compared to one another, there was no statistically significant difference in their perceived job satisfaction. Based on the dimensions analyzed in the TJSQ, both groups of educators rated responsibility as the dimension that contributed most to their job satisfaction. Both groups of educators also rated security as contributing least to their job satisfaction
On a dissipative Gross-Pitaevskii-type model for exciton-polariton condensates
We study a generalized dissipative Gross-Pitaevskii-type model arising in the
description of exciton-polariton condensates. We derive global in-time
existence results and various a-priori estimates for this model posed on the
one-dimensional torus. Moreover, we analyze in detail the long-time behavior of
spatially homogenous solutions and their respective steady states and present
numerical simulations in the case of more general initial data. We also study
the convergence to the corresponding adiabatic regime, which results in a
single damped-driven Gross-Pitaveskii equation.Comment: 25 pages, 11 figure
Leptogenesis in the presence of exact flavor symmetries
In models with flavor symmetries in the leptonic sector leptogenesis can take
place in a very different way compared to the standard leptogenesis scenario.
We study the generation of a asymmetry in these kind of models in the
flavor symmetric phase pointing out that successful leptogenesis requires (i)
the right-handed neutrinos to lie in different representations of the flavor
group; (ii) the flavons to be lighter at least that one of the right-handed
neutrino representations. When these conditions are satisfied leptogenesis
proceeds due to new contributions to the CP violating asymmetry and -depending
on the specific model- in several stages. We demonstrate the validity of these
arguments by studying in detail the generation of the asymmetry in a
scenario of a concrete flavor model realization.Comment: 25 pages, 7 figures; version 2: A few clarifications added. Version
matches publication in JHE
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