Competition of rotation and stratification in flux concentrations

In a strongly stratified turbulent layer, a uniform horizontal magnetic field can become unstable to spontaneously form local flux concentrations due to a negative contribution of turbulence to the large-scale (mean-field) magnetic pressure. This mechanism, called the negative effective magnetic pressure instability (NEMPI), is of interest in connection with dynamo scenarios where most of the magnetic field resides in the bulk of the convection zone, and not at the bottom. Recent work using the mean-field hydromagnetic equations has shown that NEMPI becomes suppressed at rather low rotation rates with Coriolis numbers as low as 0.1.}{Here we extend these earlier investigations by studying the effects of rotation both on the development of NEMPI and on the effective magnetic pressure. We also quantify the kinetic helicity from direct numerical simulations (DNS) and compare with earlier work.}{To calculate the rotational effect on the effective magnetic pressure we consider both DNS and analytical studies using the $\tau$ approach. To study the effects of rotation on the development of NEMPI we use both DNS and mean-field calculations of the 3D hydromagnetic equations in a Cartesian domain.}{We find that the growth rates of NEMPI from earlier mean-field calculations are well reproduced with DNS, provided the Coriolis number is below about 0.06. In that case, kinetic and magnetic helicities are found to be weak. For faster rotation, dynamo action becomes possible. However, there is an intermediate range of rotation rates where dynamo action on its own is not yet possible, but the rotational suppression of NEMPI is being alleviated.}{Production of magnetic flux concentrations through the suppression of turbulent pressure appears to be possible only in the upper-most layers of the Sun, where the convective turnover time is less than 2 hours.}Comment: 13 pages, 13 figures submitted to A&

Flavour physics constraints in the BMSSM

We study the implications of the presence of the two leading-order, non-renormalizable operators in the Higgs sector of the MSSM to flavour physics observables. We identify the constraints of flavour physics on the parameters of the BMSSM when we: a) focus on a region of parameters for which electroweak baryogenesis is feasible, b) use a CMSSM-like parametrization, and c) consider the case of a generic NUHM-type model. We find significant differences as compared to the standard MSSM case.Comment: 22 pages, 7 figure

A Review of ENSO Influence on the North Atlantic. A Non-Stationary Signal

ReviewThe atmospheric seasonal cycle of the North Atlantic region is dominated by meridional movements of the circulation systems: from the tropics, where the West African Monsoon and extreme tropical weather events take place, to the extratropics, where the circulation is dominated by seasonal changes in the jetstream and extratropical cyclones. Climate variability over the North Atlantic is controlled by various mechanisms. Atmospheric internal variability plays a crucial role in the mid-latitudes. However, El Niño-Southern Oscillation (ENSO) is still the main source of predictability in this region situated far away from the Pacific. Although the ENSO influence over tropical and extra-tropical areas is related to different physical mechanisms, in both regions this teleconnection seems to be non-stationary in time and modulated by multidecadal changes of the mean flow. Nowadays, long observational records (greater than 100 years) and modeling projects (e.g., CMIP) permit detecting non-stationarities in the influence of ENSO over the Atlantic basin, and further analyzing its potential mechanisms. The present article reviews the ENSO influence over the Atlantic region, paying special attention to the stability of this teleconnection over time and the possible modulators. Evidence is given that the ENSO–Atlantic teleconnection is weak over the North Atlantic. In this regard, the multidecadal ocean variability seems to modulate the presence of teleconnections, which can lead to important impacts of ENSO and to open windows of opportunity for seasonal predictability.We thank the Climatic Research Unit (CRU), the National Centers for Environmental Prediction (NCEP), the Met Office Hadley Centre and the US National Hurricane Center (NHC) for the Land Precipitation, reanalysis, SST and HURDAT2 datasets, respectively. Belen Rodríguez-Fonseca, Roberto Suárez-Moreno, Jorge López-Parages, Iñigo Gómara, Elsa Mohino, Teresa Losada and Antonio Castaño-Tierno are supported by the research projects PREFACE (EUFP7/2007-2013 Grant Agreement 603521) and MULCLIVAR (CGL2012-38923-C02-01-Spanish Ministry of Economy and Competitiveness). Blanca Ayarzagüena is supported by the Natural Environment Research Council (grant number NE/M006123/1). Julián Villamayor is granted through a scholarship from the MICINN—Spanish government (BES-2013-063821

A Semantic Portal for the International Affairs Sector

The Royal Institute Elcano(dagger) (Real Instituto Elcano) in Spain is a prestigious independent political institute whose mission is to comment on the political situation in the world focusing on its relation to Spain. As part of its dissemination strategy it operates a public website. The online content can be accessed by navigating through categories or by a keyword-based, full text search engine. The work described in this paper aims at improving access to the content. We describe an approach, tools and techniques that allow building a semantic portal, where access is based on the meaning of concepts and relations of the International Affairs domain. The approach comprises an automatic ontology-based annotator, a semantic search engine with a natural language inter-face, a web publication tool allowing semantic navigation, and a 3D visualization component. The semantic portal is currently being tested by the Institute

Internet-delivered guided self-help Acceptance and Commitment Therapy for family carers of people with dementia (iACT4CARERS): A feasibility study

Objectives: The feasibility of research into internet-delivered guided self-help Acceptance and Commitment Therapy (ACT) for family carers of people with dementia is not known. This study assessed this in an uncontrolled feasibility study. // Method: Family carers of people with dementia with mild to moderate anxiety or depression were recruited from primary and secondary healthcare services in the UK. Participants were offered eight, guided, self-help online ACT sessions adapted for the needs of family carers of people with dementia with optional online peer support groups. Pre-defined primary indicators of success included recruitment of 30 eligible carers over 6 months and ≥70% completing at least two online sessions. // Results: Thirty-three participants (110% of the target sample) were recruited over 6 months and 30 participants (91%) completed two or more sessions, and thus both indicators of success were met. Further, 70% of participants completed seven or all eight sessions, and 27% of participants were lost to follow-up, but none of the reasons for early withdrawal were related to the intervention. // Conclusion: This study supports the feasibility, including recruitment and treatment completion. A full-scale trial to assess the clinical- and cost-effectiveness of the intervention including its long-term effects is warranted

Detection of a gamma-ray flare from the high-redshift blazar DA 193

High-redshift ($z>2$) blazars are the most powerful members of the blazar family. Yet, only a handful of them have both X-ray and $\gamma$-ray detection, thereby making it difficult to characterize the energetics of the most luminous jets. Here, we report, for the first time, the Fermi-Large Area Telescope detection of the significant $\gamma$-ray emission from the high-redshift blazar DA 193 ($z=2.363$). Its time-averaged $\gamma$-ray spectrum is soft ($\gamma$-ray photon index = $2.9\pm0.1$) and together with a relatively flat hard X-ray spectrum (14$-$195 keV photon index = $1.5\pm0.4$), DA 193 presents a case to study a typical high-redshift blazar with inverse Compton peak being located at MeV energies. An intense GeV flare was observed from this object in the first week of 2018 January, a phenomenon rarely observed from high-redshift sources. What makes this event a rare one is the observation of an extremely hard $\gamma$-ray spectrum (photon index = $1.7\pm0.2$), which is somewhat unexpected since high-redshift blazars typically exhibit a steep falling spectrum at GeV energies. The results of our multi-frequency campaign, including both space- (Fermi, NuSTAR, and Swift) and ground-based (Steward and Nordic Optical Telescope) observatories, are presented and this peculiar $\gamma$-ray flare is studied within the framework of a single-zone leptonic emission scenario.Comment: 14 pages, 9 figures, 2 tables, to appear in the Astrophysical Journa

Levels and variables associated with psychological distress during confinement due to the coronavirus pandemic in a community sample of Spanish adults

Due to the COVID-19 pandemic's consequences and the state of alarm, literature has shown that people worldwide have experienced severe stressors that have been associated with increased prevalence of emotional distress. In this study, we explored psychological distress (depression, anxiety, and somatization symptoms) using an online survey platform in a sample of 1,781 Spanish adults during the confinement due to COVID-19, relationships between distress and sleep problems, affect, pain, sleep, emotional regulation, gender, type of housing, history of psychopathology, and living alone during the confinement, and differences depending on demographic and psychological variables. Results showed that between 25% and 39% of the sample referred to clinically significant levels of distress. In addition, women showed higher levels of distress, negative affect, perception of pain, and cognitive reappraisal and lower levels of emotional suppression and sleep quality than men. A history of psychopathology, being younger, living alone or in a flat was associated with higher distress. Finally, the variables most strongly related to distress were negative and positive affect, levels of pain, sleep quality, and emotional suppression. Our results highlight the important role of emotional suppression, cognitive reappraisal, and loneliness and the impact of being a woman and younger in Spain during the COVID-19 pandemic. Therefore, it would be necessary to provide assessments of distress levels in these population groups and focus psychological preventive and therapeutic online interventions on expressing emotions and preventing loneliness

Baryogenesis at Low Reheating Temperatures

We note that the maximum temperature during reheating can be much greater than the reheating temperature $T_r$ at which the Universe becomes radiation dominated. We show that the Standard Model anomalous $(B+L)$-violating processes can therefore be in thermal equilibrium for 1 GeV \simlt T_{r}\ll 100 GeV. Electroweak baryogenesis could work and the traditional upper bound on the Higgs mass coming from the requirement of the preservation of the baryon asymmetry may be relaxed. Alternatively, the baryon asymmetry may be reprocessed by sphaleron transitions either from a $(B-L)$ asymmetry generated by the Affleck-Dine mechanism or from a chiral asymmetry between $e_R$ and $e_L$ in a $B-L = 0$ Universe. Our findings are also relevant to the production of the baryon asymmetry in large extra dimension models.Comment: 4 pages, version to appear in PRL: references added, new titl

Atenuação de Ondas e Proteção à Linha de Costa por um Sistema de Recife em Franja

While knowledge on coastal dynamics is essential to guarantee well-informed decision making, information is still scarce, particularly regarding areas with the presence of coral reefs and other complex ecosystems. The objective of the present study was to contribute towards the understanding of wave attenuation and shoreline protection at different tide moments by a fringing reef system located in a Southwestern Atlantic archipelago. The predominant directions of offshore waves adjacent to the archipelago were ESE, SE, E and SSE. Coral reefs demonstrated high efficiency in wave height attenuation even under higher energy conditions during high tides. Erosion hot-spots along the archipelago were associated with rip currents, which were greatly reduced or absent during low tides. Coral reef conservation is essential to maintain shoreline protection and information on reef geomorphology should be included in reef status protocols to help advance this field of knowledgeConhecimento sobre dinâmica costeira é essencial para tomadas de decisão baseadas em evidências, no entanto esse tipo de informação ainda é escasso, particularmente em áreas com recifes de coral e outros ecossistemas complexos. O objetivo deste estudo foi contribuir para o entendimento de atenuação de ondas e proteção costeira em momentos distintos por um sistema de recife em franja em um arquipélago do Atlântico Sudoeste. As direções predominantes de ondas offshore foram ESE, SE, E and SSE. Os recifes de coral mostraram alta eficiência em reduzir a altura de ondas incidentes mesmo em condições energéticas durante marés altas. Focos de erosão ao longo do arquipélago foram associadas a correntes de retorno, que eram muito débeis ou até ausentes durante as marés baixas. A conservação dos recifes de coral é essencial para manter a proteção à linha de costa e informação sobre a geomorfologia dos recifes deveria ser incluída em protocolos de monitoramento.This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001. C.I. Elliff is thankful to the Environmental Hydraulics Institute of the Universidad de Cantabria (IHCantabria) for the immense support. M. González and V. Cánovas acknowledge the support of the Sociedad para el Desarrollo Regional de Cantabria (SODERCAN) under Grant ID16-IN-04

Rotational effects on the negative magnetic pressure instability

The surface layers of the Sun are strongly stratified. In the presence of turbulence with a weak mean magnetic field, a large-scale instability resulting in the formation of non-uniform magnetic structures, can be excited over the scale of many turbulent eddies or convection cells. This instability is caused by a negative contribution of turbulence to the effective (mean-field) magnetic pressure and has previously been discussed in connection with the formation of active regions and perhaps sunspots. We want to understand the effects of rotation on this instability in both two and three dimensions. We use mean-field magnetohydrodynamics in a parameter regime in which the properties of the negative effective magnetic pressure instability have previously been found to be in agreement with those of direct numerical simulations. We find that the instability is suppressed already for relatively slow rotation with Coriolis numbers (i.e. inverse Rossby numbers) around 0.2. The suppression is strongest at the equator. In the nonlinear regime, we find traveling wave solutions with propagation in the prograde direction at the equator with additional poleward migration away from the equator. The prograde rotation of the magnetic pattern near the equator is argued to be a possible explanation for the faster rotation speed of magnetic tracers found on the Sun. In the bulk of the domain, kinetic and current helicities are negative in the northern hemisphere and positive in the southern.Comment: 8 pages, 13 figures, submitted to A&