Dynamics of bistable N\'eel domain walls under spin-orbit torque

N\'eel magnetic domain walls that are stabilized by achiral energy terms instead of the usual Dzyaloshinskii-Moriya interaction will be bistable, with the two possible chiral forms being degenerate. Here we focus on the theoretical study of the spin-orbit torque driven dynamics of such bistable N\'eel domain walls. We find that, for a given domain wall, two propagation directions along a nanowire are possible, depending on its initial state. These dynamics also exhibit complex dependence on the spin-orbit torque magnitude, leading to important transient regimes. Finally, a few ways are proposed for controlled or random reversal of the domain wall propagation direction. A robust analytical model which handles all the observed behaviors of such domain walls is developed and validated by comparing with numerical simulations. The obtained new dynamics open the way for new uses of domain walls in information storage and processing devices

Visualization of Endothelial Actin Cytoskeleton in the Mouse Retina

Angiogenesis requires coordinated changes in cell shape of endothelial cells (ECs), orchestrated by the actin cytoskeleton. The mechanisms that regulate this rearrangement in vivo are poorly understood - largely because of the difficulty to visualize filamentous actin (F-actin) structures with sufficient resolution. Here, we use transgenic mice expressing Lifeact-EGFP to visualize F-actin in ECs. We show that in the retina, Lifeact-EGFP expression is largely restricted to ECs allowing detailed visualization of F-actin in ECs in situ. Lifeact-EGFP labels actin associated with cell-cell junctions, apical and basal membranes and highlights actin-based structures such as filopodia and stress fiber-like cytoplasmic bundles. We also show that in the skin and the skeletal muscle, Lifeact-EGFP is highly expressed in vascular mural cells (vMCs), enabling vMC imaging. In summary, our results indicate that the Lifeact-EGFP transgenic mouse in combination with the postnatal retinal angiogenic model constitutes an excellent system for vascular cell biology research. Our approach is ideally suited to address structural and mechanistic details of angiogenic processes, such as endothelial tip cell migration and fusion, EC polarization or lumen formation

Trypanosoma rangeli: a new perspective for studying the modulation of immune reactions of Rhodnius prolixus

Insects are exposed to a wide range of microorganisms (bacteria, fungi, parasites and viruses) and have interconnected powerful immune reactions. Although insects lack an acquired immune system they have well-developed innate immune defences that allow a general and rapid response to infectious agents

Pocket-sized focused cardiac ultrasound: Strengths and limitations

SummaryFocused cardiac ultrasound (FCU) has emerged in recent years and has created new possibilities in the clinical assessment of patients both in and out of hospital. The increasing portability of echocardiographic devices, with some now only the size of a smartphone, has widened the spectrum of potential indications and users, from the senior cardiologist to the medical student. However, many issues still need to be addressed, especially the acknowledgment of the advantages and limitations of using such devices for FCU, and the extent of training required in this rapidly evolving field. In recent years, an increasing number of studies involving FCU have been published with variable results. This review outlines the evidence for the use of FCU with pocket-echo to address specific questions in daily clinical practice

Efeitos de doses de nitrogênio e potássio por fertirrigação na cultura da banana.

A banana (Musa spp.) pertencente ao gênero Musa e família Musaceae, é originária das regiões tropicais do mundo. Objetivou-se avaliar o efeito de cinco doses de nitrogênio e cinco doses de potássio aplicadas através da água de irrigação por microaspersão nos parâmetros de produção da bananeira cultivar prata anã

Habitual exercise program protects murine intestinal, skeletal, and cardiac muscles against aging

Aging and aerobic exercise are two conditions known to interfere with health and quality of life, most likely by inducing oxidative stress to the organism. We studied the effects of aging on the morphological and functional properties of skeletal, cardiac, and intestinal muscles and their corresponding oxidative status in C57BL/6 mice and investigated whether a lifelong moderate exercise program would exert a protective effect against some deleterious effects of aging. As expected, aged animals presented a significant reduction of physical performance, accompanied by a decrease of gastrocnemius cross-sectional area and cardiac hypertrophy. However, most interesting was that aging dramatically interfered with the intestinal structure, causing a significant thickening of the ileum muscular layer. Senescent intestinal myocytes displayed many mitochondria with disorganized cristae and the presence of cytosolic lamellar corpuscles. Lipid peroxidation of ileum and gastrocnemius muscle, but not of the heart, increased in aged mice, thus suggesting enhanced oxidative stress. With exception of the intestinal muscle responsiveness, animals submitted to a daily session of 60 min, 5 days/wk, at 13 up to 21 m/min of moderate running in treadmill during animal life span exhibited a reversion of all the observed aging effects on intestinal, skeletal, and heart muscles. the introduction of this lifelong exercise protocol prevented the enhancement of lipid peroxidation and sarcopenia and also preserved cellular and ultracellular structures of the ileum This is the first time that the protective effect of a lifelong regular aerobic physical activity against the deleterious effects of aging on intestinal muscle was demonstrated.Universidade Federal de São Paulo, Escola Paulista Med, Dept Biophys, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Physiol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Pathol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Morphol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Biophys, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Physiol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Pathol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Morphol, BR-04023062 São Paulo, BrazilWeb of Scienc

A Nike e o Brasil imaginado: a produção do comercial Mandingas para a Copa do Mundo de 2010

The four advertising for launching Nike campaigns for the World Cups from 2006 to 2018, and particularly the most extensive of them, Mandingas, for the 2010 World Cup, are the subject of this essay, focusing on the imagined Brazil from which this ad production drift. It is intended to show how the largest sporting goods company in the world interacts with the social imaginary, in a double sense, both in the search for its references in that imaginary and, at the same time, in the food and reproduction of these symbolic constructions through the films produced. Methodologically, the research is based on Depth Hermeneutics, as formulated by John B. Thompson, with the support of content analysis and in the broader light of understanding as a method. The text hopes to promote an understanding of how advertising can act as a link between the brand and its audience, which means, in the specific case, with the Brazilian nation itself.Os quatro comerciais de lançamento das campanhas da Nike para as Copas do Mundo de 2006 a 2018, e particularmente o mais extenso deles, Mandingas, para a Copa de 2010, constituem o objeto deste ensaio, com foco no Brasil imaginado do qual essa produção publicitária deriva. Pretende-se mostrar como a maior empresa de artigos esportivos do mundo interage com o imaginário social, num duplo sentido, tanto da busca de seus referenciais nesse imaginário como, ao mesmo tempo, de alimento e reprodução dessas construções simbólicas por meio dos filmes produzidos. Metodologicamente, a pesquisa toma por base a Hermenêutica de Profundidade, como formulada por John B. Thompson, com o suporte da análise de conteúdo e à luz mais ampla da compreensão como método. O texto espera promover a compreensão a respeito de como a publicidade pode atuar como formadora de vínculos entre a marca e o seu público, o que significa, no caso específico, com a própria nação brasileira