Rogue waves of the Sasa-Satsuma equation in a chaotic wave field

We study the properties of the chaotic wave fields generated in the frame of the Sasa-Satsuma equation (SSE). Modulation instability results in a chaotic pattern of small-scale filaments with a free parameter - the propagation constant k. The average velocity of the filaments is approximately given by the group velocity calculated from the dispersion relation for the plane-wave solution. Remarkably, our results reveal the reason for the skewed profile of the exact SSE rogue-wave solutions, which was one of their distinctive unexplained features. We have also calculated the probability density functions for various values of the propagation constant k, showing that probability of appearance of rogue waves depends on k

Near Elimination of Ventricular Pacing in SafeR Mode Compared to DDD Modes: A Randomized Study of 422 Patients

Aims:SafeR performance versus DDD/automatic mode conversion (DDD/AMC) and DDD with a 250-ms atrioventricular (AV) delay (DDD/LD) modes was assessed toward ventricular pacing (Vp) reduction. Methods:After a 1-month run-in phase, recipients of dual-chamber pacemakers without persistent AV block and persistent atrial fibrillation (AF) were randomly assigned to SafeR, DDD/AMC, or DDD/LD in a 1:1:1 design. The main endpoint was the percentage of Vp (%Vp) at 2 months and 1 year after randomization, ascertained from device memories. Secondary endpoints include %Vp at 1 year according to pacing indication and 1-year AF incidence based on automatic mode switch device stored episodes. Results:Among 422 randomized patients (73.2 ± 10.6 years, 50% men, sinus node dysfunction 47.4%, paroxysmal AV block 30.3%, bradycardia-tachycardia syndrome 21.8%), 141 were assigned to SafeR versus 146 to DDD/AMC and 135 to DDD/LD modes. Mean %Vp at 2 months was 3.4 ± 12.6% in SafeR versus 33.6 ± 34.7% and 14.0 ± 26.0% in DDD/AMC and DDD/LD modes, respectively (P < 0.0001 for both). At 1 year, mean %Vp in SafeR was 4.5 ± 15.3% versus 37.9 ± 34.4% and 16.7 ± 28.0% in DDD/AMC and DDD/LD modes, respectively (P < 0.0001 for both). The proportion of patients in whom Vp was completely eliminated was significantly higher in SafeR (69%) versus DDD/AMC (15%) and DDD/LD (45%) modes (P < 0.0001 for both), regardless of pacing indication. The absolute risk of developing permanent AF or of remaining in AF for >30% of the time was 5.4% lower in SafeR than in the DDD pacing group (ns). Conclusions:In this selected patient population, SafeR markedly suppressed unnecessary Vp compared with DDD modes. PACE 2012; 35:392–402

The effects of environmental and non-environmental shocks on livelihoods and migration in Tanzania

Disruptive events and calamities can have major consequences for households in the predominantly agrarian communities of Eastern Africa. Here, we analyze the impacts of environmental and non-environmental shocks on migration in Tanzania using panel models and longitudinal data from the Tanzania National Panel Survey between 2008 and 2013. Shocks are defined as events that lead to losses in income, assets, or both. We find shocks resulting from changes in environmental conditions to be positively related to migration over time with more recent shocks exerting the strongest impact. According to our estimates, the probability of having a household member absent increases by 0.81% with each additional environmental shock encountered in the past 12 months. Different types of shocks have differential effects on migration with the strongest effects being observed for shocks with an immediate impact on household livelihoods, including through livestock losses and crop damage. Households in the sample are differently affected with rural, agriculturally dependent, and poor households without alternative income sources showing the strongest changes in their migration behavior in response to shocks. Our study adds important insights into the relationship between disruptive events and migration in Eastern Africa considering a broad time window and the compounding influence of different shock types. Our findings have a range of policy implications highlighting the need for a comprehensive perspective on household responses in times of distress that considers the interplay of different shock types as well as the role of context in shaping mobility patterns

Boundary multi-trace deformations and OPEs in AdS/CFT correspondence

We argue that multi-trace deformations of the boundary CFT in AdS/CFT correspondence can arise through the OPE of single-trace operators. We work out the example of a scalar field in AdS_5 with cubic self interaction. By an appropriate reparametrization of the boundary data we are able to deform the boundary CFT by a marginal operator that couples to the conformal anomaly. Our method can be used in the analysis of multi-trace deformations in N=4 SYM where the OPEs of various single-trace operators are known.Comment: 18 pages, v2 refinements and acknowledgements adde

INTEGRAL observations of TeV plerions

Amongst the sources seen in very high gamma-rays several are associated with Pulsar Wind Nebulae (``TeV plerions''). The study of hard X-ray/soft gamma-ray emission is providing an important insight into the energetic particle population present in these objects. The unpulsed emission from pulsar/pulsar wind nebula systems in the energy range accessible to the INTEGRAL satellite is mainly synchrotron emission from energetic and fast cooling electrons close to their acceleration site. Our analyses of public INTEGRAL data of known TeV plerions detected by ground based Cherenkov telescopes indicate a deeper link between these TeV plerions and INTEGRAL detected pulsar wind nebulae. The newly discovered TeV plerion in the northern wing of the Kookaburra region (G313.3+0.6 powered by the middle aged PSR J1420-6048) is found to have a previously unknown INTEGRAL counterpart which is besides the Vela pulsar the only middle aged pulsar detected with INTEGRAL. We do not find an INTEGRAL counterpart of the TeV plerion associated with the X-ray PWN ``Rabbit'' G313.3+0.1 which is possibly powered by a young pulsar.Comment: 4 pages, 6 figures, proceedings of conference "The Multi-Messenger Approach to High-Energy Gamma-ray Sources" Barcelona/Spain (2006

Evaluating the AdS dual of the critical O(N) vector model

We argue that the AdS dual of the three dimensional critical O(N) vector model can be evaluated using the Legendre transform that relates the generating functionals of the free UV and the interacting IR fixed points of the boundary theory. As an example, we use our proposal to evaluate the minimal bulk action of the scalar field that it is dual to the spin-zero ``current'' of the O(N) vector model. We find that the cubic bulk self interaction coupling vanishes. We briefly discuss the implications of our results for higher spin theories and comment on the bulk-boundary duality for subleading N.Comment: 17 pages, 1 figure, v2 references added, JHEP versio

Calculation of excited polaron states in the Holstein model

An exact diagonalization technique is used to investigate the low-lying excited polaron states in the Holstein model for the infinite one-dimensional lattice. For moderate values of the adiabatic ratio, a new and comprehensive picture, involving three excited (coherent) polaron bands below the phonon threshold, is obtained. The coherent contribution of the excited states to both the single-electron spectral density and the optical conductivity is evaluated and, due to the invariance of the Hamiltonian under the space inversion, the two are shown to contain complementary information about the single-electron system at zero temperature. The chosen method reveals the connection between the excited bands and the renormalized local phonon excitations of the adiabatic theory, as well as the regime of parameters for which the electron self-energy has notable non-local contributions. Finally, it is shown that the hybridization of two polaron states allows a simple description of the ground and first excited state in the crossover regime.Comment: 12 pages, 9 figures, submitted to PR

Local management and landscape composition affect predatory mites in European wine-growing regions

Sustainable land use in agricultural landscapes is essential to counteract the global decline of biodiversity, as well to ensure ecosystem services like natural pest control. Phytoseiid mites are key natural enemies of pest mites in vineyards but how local management and landscape context affect phytoseiid mites remains poorly known. In this study, we examined the effects of farming systems, inter-row management and landscape composition on phytoseiid mite communities in 156 vineyards across five European wine-growing regions. Our results showed that phytoseiid communities were mainly dominated by one or two phytoseiid species across Europe and that local management was a major factor affecting population densities. According to the wine-growing regions, phytoseiid mite densities benefited from integrated pest management or conventional farming compared to organic farming and from spontaneous vegetation cover compared to seeded cover crops. Moreover, mite densities benefited from increasing proportions of vineyards at the landscape scale. The farming systems effects were most likely related to the positive impact of the lower pesticide use in integrated and conventional vineyards. The positive effect of spontaneous vegetation cover could be related to a better supply of nutritive pollen as food resource compared to seeded cover crops, which depends on the plant species in the inter-row. Our findings indicated accordingly that a reduced pesticide use, and inter-row management are crucial factors for promoting pest control by predatory mites in European vineyards. Moreover, the proportion of viticultural area in the landscape is a considerable factor to retain stable phytoseiid mite populations.This research was funded by the research project SECBIVIT, which was funded through the 2017-2018 Belmont Forum and BiodivERsA joint call for research proposals, under the BiodivScen ERA-Net COFUND program, with the funding organizations: Agencia Estatal de Investigación (Ministerio de ciencia e innovación/ES/Grant #10.13039/501100011033), Austrian Science Fund (AT/Grant #I 4025-B32), Federal Ministry of Education and Research and Projektträger VDI/VDE Innovation + Technik GmbH (DE), French National Research Agency (FR), Netherlands Organisation for Scientific Research (NL), National Science Foundation (US/Grant #1850943) and Romanian Executive Agency for Higher Education, Research, Development and Innovation Funding (RO)

Mesoscopic proximity effect in double barrier Superconductor/Normal Metal junctions

We report transport measurements down to T=60mK of SININ and SNIN structures in the diffusive limit. We fabricated Al-AlOx/Cu/AlOx/Cu (SININ) and Al/Cu/AlOx/Cu (SNIN) vertical junctions. For the first time, a zero bias anomaly was observed in a metallic SININ structure. We attribute this peak of conductance to coherent multi-reflections of electrons between the two tunnel barriers. This conductance maximum is quantitatively fitted by the relevant theory of mesoscopic SININ structures. When the barrier at the SN interface is removed (SNIN structure), we observe a peak of conductance at finite voltage accompagnied by an excess of sub-gap conductance.Comment: 4 pages, 4 figures, editorially approved for publication in Phys. Rev. B Rapid Com

The holographic superconductors in higher-dimensional AdS soliton

We explore the behaviors of the holographic superconductors at zero temperature for a charged scalar field coupled to a Maxwell field in higher-dimensional AdS soliton spacetime via analytical way. In the probe limit, we obtain the critical chemical potentials increase linearly as a total dimension $d$ grows up. We find that the critical exponent for condensation operator is obtained as 1/2 independently of $d$, and the charge density is linearly related to the chemical potential near the critical point. Furthermore, we consider a slightly generalized setup the Einstein-Power-Maxwell field theory, and find that the critical exponent for condensation operator is given as $1/(4-2n)$ in terms of a power parameter $n$ of the Power-Maxwell field, and the charge density is proportional to the chemical potential to the power of $1/(2-n)$.Comment: LaTeX, 16 pages, 5 figures, typos corrected, one reference added, version to appear in European Physical Journal