109 research outputs found
Nongaussianity from Tachyonic Preheating in Hybrid Inflation
In a previous work we showed that large nongaussianities and
nonscale-invariant distortions in the CMB power spectrum can be generated in
hybrid inflation models, due to the contributions of the tachyon (waterfall)
field to the second order curvature perturbation. Here we clarify, correct, and
extend those results. We show that large nongaussianity occurs only when the
tachyon remains light throughout inflation, whereas n=4 contamination to the
spectrum is the dominant effect when the tachyon is heavy. We find constraints
on the parameters of warped-throat brane-antibrane inflation from
nongaussianity. For F-term and D-term inflation models from supergravity, we
obtain nontrivial constraints from the spectral distortion effect. We also
establish that our analysis applies to complex tachyon fields.Comment: 16 pages, 2 figures. Comments added to introductio
On difference linear periodic systems. I. Homogeneous case
summary:The paper deals with the reduction of a linear homogeneous periodic system in differences (recurrence relations) to another linear homogeneous system with constant coefficients. This makes it possible to study the existence and properties of periodic solutions, the asymptotic behavior, and to obtain all solutions in closed form
Estudio comparativo del sellado total de tres selladores
Buscando el éxito de la terapia endodóntica sabemos que uno de los ítems más difíciles dentro de nuestra especialidad es lograr la hermeticidad del conducto; a través de un sellador ideal. Hoy día seguimos buscando un sellador que cumpla con todos los requisitos esperados Objetivo: El objetivo de este trabajo fue estudiar en forma comparativa el sellado en la totalidad del conducto por medio de la técnica de transparentación. Los selladores endodónticos utilizados en esta oportunidad son el cemento de Grossman, el sellador de CPM Sealer y Roeko Seal.Facultad de Odontologí
Estudio comparativo del sellado total de tres selladores
Buscando el éxito de la terapia endodóntica sabemos que uno de los ítems más difíciles dentro de nuestra especialidad es lograr la hermeticidad del conducto; a través de un sellador ideal. Hoy día seguimos buscando un sellador que cumpla con todos los requisitos esperados Objetivo: El objetivo de este trabajo fue estudiar en forma comparativa el sellado en la totalidad del conducto por medio de la técnica de transparentación. Los selladores endodónticos utilizados en esta oportunidad son el cemento de Grossman, el sellador de CPM Sealer y Roeko Seal.Facultad de Odontologí
Estudio comparativo del sellado total de tres selladores
Buscando el éxito de la terapia endodóntica sabemos que uno de los ítems más difíciles dentro de nuestra especialidad es lograr la hermeticidad del conducto; a través de un sellador ideal. Hoy día seguimos buscando un sellador que cumpla con todos los requisitos esperados Objetivo: El objetivo de este trabajo fue estudiar en forma comparativa el sellado en la totalidad del conducto por medio de la técnica de transparentación. Los selladores endodónticos utilizados en esta oportunidad son el cemento de Grossman, el sellador de CPM Sealer y Roeko Seal.Facultad de Odontologí
Mental health trajectories among the general population and higher-risk groups following the COVID-19 pandemic in Switzerland, 2021-2023.
Mental health deteriorated in the early stages of the COVID-19 pandemic, but improved relatively quickly as restrictions were eased, suggesting overall resilience. However, longer-term follow-up of mental health in the general population is scarce.
We examined mental health trajectories in 5624 adults (58 % women; aged 18-97 years) from the Specchio-COVID19 cohort, using the Generalized Anxiety Disorder scale-2 and the Patient Health Questionnaire-2, administered each month from February to June 2021, and in Spring 2022 and 2023.
Depressive and anxiety symptoms declined during a pandemic wave from February to May 2021 (β = -0.06 [-0.07, -0.06]; -0.06 [-0.07, -0.05]), and remained lower at longer-term follow-up than at the start of the wave. Loneliness also declined over time, with the greatest decline during the pandemic wave (β = -0.25 [-0.26, -0.24]). Many higher-risk groups, including socioeconomically disadvantaged individuals, those with a chronic condition, and those living alone had poorer mental health levels throughout the study period. Women and younger individuals had a faster improvement in mental health during the pandemic wave. Loneliness trajectories were associated with mental health trajectories throughout the study period.
We cannot definitively conclude that the observed changes in mental health were due to experiences of the pandemic.
While there was a need for additional mental health support during stricter policy responses to COVID-19, overall, mental health improved relatively soon after measures were eased. Nevertheless, the persistence of mental health disparities highlights the need for further efforts from the government and healthcare practitioners to support vulnerable groups beyond the pandemic
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