Refined topological amplitudes in N=1 flux compactification

We study the implication of refined topological string amplitudes in the supersymmetric N=1 flux compactification. They generate higher derivative couplings among the vector multiplets and graviphoton with generically non-holomorphic moduli dependence. For a particular term, we can compute them by assuming the geometric engineering. We claim that the Dijkgraaf-Vafa large N matrix model with the beta-ensemble measure directly computes the higher derivative corrections to the supersymmetric effective action of the supersymmetric N=1$ gauge theory.Comment: 16 pages, v2: reference adde

Rotating BPS black holes in matter-coupled AdS(4) supergravity

Using the general recipe given in arXiv:0804.0009, where all timelike supersymmetric solutions of N=2, D=4 gauged supergravity coupled to abelian vector multiplets were classified, we construct genuine rotating supersymmetric black holes in AdS(4) with nonconstant scalar fields. This is done for the SU(1,1)/U(1) model with prepotential F=-iX^0X^1. In the static case, the black holes are uplifted to eleven dimensions, and generalize the solution found in hep-th/0105250 corresponding to membranes wrapping holomorphic curves in a Calabi-Yau five-fold. The constructed rotating black holes preserve one quarter of the supersymmetry, whereas their near-horizon geometry is one half BPS. Moreover, for constant scalars, we generalize (a supersymmetric subclass of) the Plebanski-Demianski solution of cosmological Einstein-Maxwell theory to an arbitrary number of vector multiplets. Remarkably, the latter turns out to be related to the dimensionally reduced gravitational Chern-Simons action.Comment: 23 pages, uses JHEP3.cl

Variable order Mittag-Leffler fractional operators on isolated time scales and application to the calculus of variations

We introduce new fractional operators of variable order on isolated time scales with Mittag-Leffler kernels. This allows a general formulation of a class of fractional variational problems involving variable-order difference operators. Main results give fractional integration by parts formulas and necessary optimality conditions of Euler-Lagrange type.Comment: This is a preprint of a paper whose final and definite form is with Springe

D1D5 microstate geometries from string amplitudes

We reproduce the asymptotic expansion of the D1D5 microstate geometries by computing the emission amplitudes of closed string states from disks with mixed D1D5 boundary conditions. Thus we provide a direct link between the supergravity and D-brane descriptions of the D1D5 microstates at non-zero string coupling. Microscopically, the profile functions characterizing the microstate solutions are encoded in the choice of a condensate for the twisted open string states connecting D1 and D5 branes.Comment: 21 pages; added reference

Evaluation of Methods to Characterize the Change of the Respiratory Sinus Arrhythmia with Age in Sleep Apnea Patients

The High Frequency (HF) band of the power spectrum of the Heart Rate Variability (HRV) is widely accepted to contain information related to the respiration. However, it is known that this often results in misleading estimations of the strength of the Respiratory Sinus Arrhythmia (RSA). In this paper, different approaches to characterize the change of the RSA with age, combining HRV and respiratory signals, are studied. These approaches are the bandwidths in the power spectral density estimations, bivariate phase rectified signal averaging, information dynamics, a time-frequency representation, and a heart rate decomposition based on subspace projections. They were applied to a dataset of sleep apnea patients, specifically to periods without apneas and during NREM sleep. Each estimate reflected a different relationship between RSA and age, suggesting that they all capture the cardiorespiratory information in a different way. The comparison of the estimates indicates that the approaches based on the extraction of respiratory information from HRV provide a better characterization of the age-dependent degradation of the RSA

Validity of the Polar V800 heart rate monitor to measure RR intervals at rest

Purpose To assess the validity of RR intervals and short-term heart rate variability (HRV) data obtained from the Polar V800 heart rate monitor, in comparison to an electrocardiograph (ECG). Method Twenty participants completed an active orthostatic test using the V800 and ECG. An improved method for the identification and correction of RR intervals was employed prior to HRV analysis. Agreement of the data was assessed using intra-class correlation coefficients (ICC), Bland–Altman limits of agreement (LoA), and effect size (ES). Results A small number of errors were detected between ECG and Polar RR signal, with a combined error rate of 0.086 %. The RR intervals from ECG to V800 were significantly different, but with small ES for both supine corrected and standing corrected data (ES 0.999 for both supine and standing corrected intervals. When analysed with the same HRV software no significant differences were observed in any HRV parameters, for either supine or standing; the data displayed small bias and tight LoA, strong ICC (>0.99) and small ES (≤0.029). Conclusions The V800 improves over previous Polar models, with narrower LoA, stronger ICC and smaller ES for both the RR intervals and HRV parameters. The findings support the validity of the Polar V800 and its ability to produce RR interval recordings consistent with an ECG. In addition, HRV parameters derived from these recordings are also highly comparable

Supersymmetric AdS_4 black holes and attractors

Using the general recipe given in arXiv:0804.0009, where all timelike supersymmetric solutions of N=2, D=4 gauged supergravity coupled to abelian vector multiplets were classified, we construct the first examples of genuine supersymmetric black holes in AdS_4 with nonconstant scalar fields. This is done for various choices of the prepotential, amongst others for the STU model. These solutions permit to study the BPS attractor flow in AdS. We also determine the most general supersymmetric static near-horizon geometry and obtain the attractor equations in gauged supergravity. As a general feature we find the presence of flat directions in the black hole potential, i.e., generically the values of the moduli on the horizon are not completely specified by the charges. For one of the considered prepotentials, the resulting moduli space is determined explicitely. Still, in all cases, we find that the black hole entropy depends only on the charges, in agreement with the attractor mechanism.Comment: 25 pages, uses JHEP3.cl

Domain walls in three dimensional gauged supergravity

We explicitly construct two Chern-Simons gauged supergravities in three dimensions with N=4 and N=8 supersymmetries and non-semisimple gauge groups. The N=4 theory has scalar manifold $SO(4,3)/SO(4)\times SO(3)$ with the gauge group $SO(3)\ltimes (\mathbf{T}^3,\hat{\mathbf{T}}^3)$. The theory describes (1,0) six dimensional supergravity reduced on an SU(2) group manifold. The equivalent Yang-Mills type gauged supergravity has SO(3) gauge group coupled to three massive vector fields. The N=8 theory is described by $SO(8,8)/SO(8)\times SO(8)$ scalar manifold, and the gauge group is given by $SO(8)\ltimes \mathbf{T}^{28}$. The theory is a truncation of the $SO(8)\ltimes \mathbf{T}^{28}$ gauged N=16 theory with scalar manifold $E_{8(8)}/SO(16)$ and can be obtained by an S^7 compactification of type I theory in ten dimensions. Domain wall solutions of both gauged supergravities are analytically found and can be uplifted to higher dimensions. These provide domain wall vacua in the three dimensional gauged supergravity framework which might be useful for the study of Domain Wall$_3$/QFT$_2$ correspondence.Comment: 19 pages, no figures, typoes and a mistake in a sign corrected, clarifications on the notations adde

The selectivity, voltage-dependence and acid sensitivity of the tandem pore potassium channel TASK-1 : contributions of the pore domains

We have investigated the contribution to ionic selectivity of residues in the selectivity filter and pore helices of the P1 and P2 domains in the acid sensitive potassium channel TASK-1. We used site directed mutagenesis and electrophysiological studies, assisted by structural models built through computational methods. We have measured selectivity in channels expressed in Xenopus oocytes, using voltage clamp to measure shifts in reversal potential and current amplitudes when Rb+ or Na+ replaced extracellular K+. Both P1 and P2 contribute to selectivity, and most mutations, including mutation of residues in the triplets GYG and GFG in P1 and P2, made channels nonselective. We interpret the effects of these—and of other mutations—in terms of the way the pore is likely to be stabilised structurally. We show also that residues in the outer pore mouth contribute to selectivity in TASK-1. Mutations resulting in loss of selectivity (e.g. I94S, G95A) were associated with slowing of the response of channels to depolarisation. More important physiologically, pH sensitivity is also lost or altered by such mutations. Mutations that retained selectivity (e.g. I94L, I94V) also retained their response to acidification. It is likely that responses both to voltage and pH changes involve gating at the selectivity filter

"We can't carry the weight of the whole world": illness experiences among Peruvian older adults with symptoms of depression and anxiety

Background: Despite the high levels of depression and anxiety symptoms in old age, the use of mental health services in this population is low. Help-seeking behaviors are shaped by how an individual perceives and experiences their illness. The objective of this study was to characterize the illness experiences of Peruvian older adults with depression and anxiety symptoms in order to lay the foundation for tailored community-based mental health interventions. Methods: In this qualitative study, we conducted in-depth interviews with a purposively selected sample of older adults (≥ 60 years) from peri-urban areas of Lima, Peru. We included individuals with only depressive symptoms (Patient Health Questionnaire-9 ≥ 10), only anxiety symptoms (Beck Anxiety Inventory ≥ 16), with depressive and anxiety symptoms, and older adults who mentioned they had received mental health treatment/care. The interview guide included the following topics: perceptions and experiences about depression and anxiety; perceptions about the relationship between physical chronic diseases and mental health; experiences with mental health professionals and treatments, and coping mechanisms. Data collection was conducted between October 2018 and February 2019. Results: We interviewed 38 participants (23 women, 15 men) with a mean age of 67.9 years. Participants' ideas and perceptions of depression and anxiety showed considerable overlap. Participants attributed depression and anxiety mainly to familial and financial problems, loneliness, loss of independence and past traumatic experiences. Coping strategies used by older adults included 'self-reflection and adaptation' to circumstances, 'do your part', and seeking 'emotional support' mainly from non-professionals (relatives, friends, acquaintances, and religion). Conclusions: Illness experiences of depression and anxiety set the pathway for tailored community-based mental health interventions for older adults. Overlapping narratives and perceptions of depression and anxiety suggest that these conditions should be addressed together. Mental health interventions should incorporate addressing areas related to depression and anxiety such as prevention of loss of independence, trauma, and loneliness. Good acceptability of receiving emotional support for non-professionals might offer an opportunity to incorporate them when delivering mental health care to older adults