Resonant driving of magnetization precession in a ferromagnetic layer by coherent monochromatic phonons

We realize resonant driving of the magnetization precession by monochromatic phonons in a thin ferromagnetic layer embedded into a phononic Fabry-Pérot resonator. A femtosecond laser pulse excites resonant phonon modes of the structure in the 10−40 GHz frequency range. By applying an external magnetic field, we tune the precession frequency relative to the frequency of the phonons localized in the cavity and observe an enormous increase in the amplitude of the magnetization precession when the frequencies of free magnetization precession and phonons localized in the cavity are equal

Photonic molecules and spectral engineering

This chapter reviews the fundamental optical properties and applications of pho-tonic molecules (PMs) - photonic structures formed by electromagnetic coupling of two or more optical microcavities (photonic atoms). Controllable interaction between light and matter in photonic atoms can be further modified and en-hanced by the manipulation of their mutual coupling. Mechanical and optical tunability of PMs not only adds new functionalities to microcavity-based optical components but also paves the way for their use as testbeds for the exploration of novel physical regimes in atomic physics and quantum optics. Theoretical studies carried on for over a decade yielded novel PM designs that make possible lowering thresholds of semiconductor microlasers, producing directional light emission, achieving optically-induced transparency, and enhancing sensitivity of microcavity-based bio-, stress- and rotation-sensors. Recent advances in material science and nano-fabrication techniques make possible the realization of optimally-tuned PMs for cavity quantum electrodynamic experiments, classical and quantum information processing, and sensing.Comment: A review book chapter: 29 pages, 19 figure

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Methane emissions from sheep grazing Pearl millet (Penissetum americanum (L.) Leeke) swards fertilized with increasing nitrogen levels

This study aimed at quantifying methane emissions from sheep grazing pearl millet swards (Penissetum americanum (L.) Leeke) as affected by nitrogen (N) fertilization doses (50, 100, 200 and 400 kg N ha−1). The experimental period was 70 days of pasture use, from February to April 2011. The grazing method was continuous stocking with variable stocking rate, so pasture structure was intended to be similar (30 cm sward height) among treatments. Thirty six tester animals aging 5 months and initially weighing 20 ± 1.6 kg were used for evaluations. Intake (OMI) was estimated by their relationship with N content on faeces. The sulfur hexafluoride (SF6) technique was used for two sampling periods of five consecutive days each to quantify daily methane (CH4) production. Parameters related to sward structure was not affected by N fertilization, but herbage accumulation increased linearly (P 0.05) OMI, and methane emissions expressed as a ratio of OMI. Results indicated that increasing nitrogen doses decrease methane emissions per animal. When expressed as grams of methane per kilogram of organic matter ingested or energy converted into methane, no difference was observed. However, emissions per unit area increase as a consequence of higher stocking rates allowed by the increase in forage production. Sheep emitted 16.3 g of methane per kg of ingested organic matter and converted 5.1% of ingested gross energy into methane.Fil: Amaral, G.A.. Universidade Federal do Rio Grande do Sul; BrasilFil: David, D.B.. Universidade Federal do Rio Grande do Sul; BrasilFil: Gere, José Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Savian, J.V.. Universidade Federal do Rio Grande do Sul; BrasilFil: Kohmann, M.M.. Universidade Federal do Rio Grande do Sul; BrasilFil: Nadin, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Sánchez Chopa, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Bayer, C.. Universidade Federal do Rio Grande do Sul; BrasilFil: Carvalho, P.C.F.. Universidade Federal do Rio Grande do Sul; Brasi