Excitation of standing kink oscillations in coronal loops

In this work we review the efforts that have been done to study the excitation of the standing fast kink body mode in coronal loops. We mainly focus on the time-dependent problem, which is appropriate to describe flare or CME induced kink oscillations. The analytical and numerical studies in slab and cylindrical loop geometries are reviewed. We discuss the results from very simple one-dimensional models to more realistic (but still simple) loop configurations. We emphasise how the results of the initial value problem complement the eigenmode calculations. The possible damping mechanisms of the kink oscillations are also discussed

Avaliação da resistência de clones de Coffea canephora ao nematoide-das-galhas submetidos a ambiente de extrema umidade.

O objetivo deste trabalho foi avaliar o efeito da temperatura e umidade em dois clones de C. canephora, resistente e suscetível ao nematoide-das-galhas

Resposta de resistência de clones de Coffea canephora ao nematoide-das-galhas (Meloidogyne incognita) em função da temperatura.

Alterações climáticas e o efeito destas sobre as interações patógenos e hospedeiros é um aspecto que tem ganhado destaque no atual contexto de produção agrícola mundial. Considerando que a cultura do cafeeiro pode ser fortemente afetada por essas mudanças, objetivou-se nesse trabalho determinar os efeitos da temperatura sobre a resposta de resistência de clones de Coffea canephora Conilon ao nematoide-das-galhasdo cafeeiro

Allergenic Shrimp Tropomyosin Distinguishes from a Non-Allergenic Chicken Homolog by Pronounced Intestinal Barrier Disruption and Downstream Th2 Responses in Epithelial and Dendritic Cell (Co)Culture

BACKGROUND: Tropomyosins (TM) from vertebrates are generally non-allergenic, while invertebrate homologs are potent pan-allergens. This study aims to compare the risk of sensitization between chicken TM and shrimp TM through affecting the intestinal epithelial barrier integrity and type 2 mucosal immune activation. METHODS: Epithelial activation and/or barrier effects upon exposure to 2-50 μg/mL chicken TM, shrimp TM or ovalbumin (OVA) as a control allergen, were studied using Caco-2, HT-29MTX, or HT-29 intestinal epithelial cells. Monocyte-derived dendritic cells (moDC), cocultured with HT-29 cells or moDC alone, were exposed to 50 μg/mL chicken TM or shrimp TM. Primed moDC were cocultured with naïve Th cells. Intestinal barrier integrity (TEER), gene expression, cytokine secretion and immune cell phenotypes were determined in these human in vitro models. RESULTS: Shrimp TM, but not chicken TM or OVA exposure, profoundly disrupted intestinal barrier integrity and increased alarmin genes expression in Caco-2 cells. Proinflammatory cytokine secretion in HT-29 cells was only enhanced upon shrimp TM or OVA, but not chicken TM, exposure. Shrimp TM enhanced the maturation of moDC and chemokine secretion in the presence or absence of HT-29 cells, while only in the absence of epithelial cells chicken TM activated moDC. Direct exposure of moDC to shrimp TM increased IL13 and TNFα secretion by Th cells cocultured with these primed moDC, while shrimp TM exposure via HT-29 cells cocultured with moDC sequentially increased IL13 expression and IL4 secretion in Th cells. CONCLUSIONS: Shrimp TM, but not chicken TM, disrupted the epithelial barrier while triggering type 2 mucosal immune activation, both of which are key events in allergic sensitization

Characterization of the biochemical response of Coffea canephora accessions regarding resistance to orange rust.

Título em português: Caracterização da resposta bioquímica de acessos de Coffea canephora quanto a resistência à ferrugem alaranjada