Signalling pathways in pollen germination and tube growth

Summary. Signalling is an integral component in the establishment and maintenance of cellular identity. In plants, tip-growing cells represent an ideal system to investigate signal transduction mechanisms, and among these, pollen tubes (PTs) are one of the favourite models. Many signalling pathways have been identified during germination and tip growth, namely, Ca2+, calmodulin, phosphoinositides, protein kinases, cyclic AMP, and GTPases. These constitute a large and complex web of signalling networks that intersect at various levels such as the control of vesicle targeting and fusion and the physical state of the actin cytoskeleton. Here we discuss some of the most recent advances made in PT signal transduction cascades and their implications for our future research. For reasons of space, emphasis was given to signalling mechanisms that control PT reorientation, so naturally many other relevant works have not been cited

Rooting Pattern Distribution and Spatial Variability of Italian Ryegrass (Lolium Multiflorum Lam) in a Mediterranean Region

It is estimated that less than 10% of the studies on pastures and forages have evaluated the subterranean biomass production. The objective of this study was to evaluate for a Mediterranean region the rooting characteristics and spatial variability of Italian ryegrass (Lolium multiflorum Lam) under two different soil water status conditions

Avaliação de genótipos de girassol em safrinha no cerrado do Distrito Federal em 2011 em ensaio de segundo ano.

O experimento foi instalado na Embrapa Cerrados e avaliou o comportamento de 10 genótipos de girassol em safrinha, em ensaio de segundo ano. Foram avaliados: rendimento de grãos, altura de plantas, número de plantas quebradas, peso de mil aquênios e dias para floração plena no período de 16/02/2011 a 15/06/2011. O rendimento médio ficou em 2.912,60 kg.ha-1e o rendimento máximo foi apresentado pelo genótipo BRS G 29 (3.410,29 kg.ha ). A altura média das plantas foi de 169,75 cm, o peso médio de mil aquênios foi de 52,8 g e o número médio de dias para floração foi de 62. As condições ambientais expressas pela safrinha no Cerrado do Distrito Federal em 2011 colocam o girassol como uma opção de cultivo no sistema de produção agrícola dessa região. EVALUATION SUNFLOWER GENOTYPES ON OUT OF SEASON CROP AT DISTRITO FEDERAL SAVANNA IN 2011 IN SECOND YEAR TEST. The experiment was conducted at Embrapa Cerrados and were evaluated the behaviors of 10 sunflower genotypes in off-season, in second year test. Were evaluated: yield, plants height, number of broken plants, weight of a thousand seeds and days to complete flowering between February 16thand June 15th. The average grain yield was 2.912,60 kg.ha and the highest yield was presented by BRS G 29 (3.410,29 kg.ha-1). The mean value for plants height was 169,75 cm. The average weight of a thousand seeds and number of days to complete flowering were 52,8 g and 62 days, respectively. Environmental conditions expressed in offseason period at Distrito Federal savanna in 2011 puts sunflower as an option in agricultural production system in this region

Comportamento de genótipos de girassol em safrinha no cerrado do Distrito Federal em 2011 em ensaio de primeiro ano.

Um ensaio de primeiro ano de avaliação foi conduzido na Embrapa Cerrados com o objetivo de avaliar o comportamento de genótipos de girassol em safrinha, em relação às variáveis: rendimento de grãos, altura de plantas, número de plantas quebradas, peso de mil aquênios, dias para floração plena em 19 materiais genéticos no período de 16/02/2011 a 15/06/2011. O rendimento médio ficou em torno de 3.390,67 kg.ha-1e a rendimento de grãos máximo foi obtida pelo genótipo BRS G 30(5.489,67 kg.ha-1). A altura média das plantas foi de 175 cm, o peso médio de mil aquênios foi 57,03 g e o período para floração plena ficou em torno de 64 dias. As condições ambientais expressas na safrinha do Cerrado do Distrito Federal, em 2011, fazem com que o girassol seja uma opção de cultivo no sistema de produção agrícola. SUNFLOWER GENOTYPES AGRONOMIC PERFORMANCE IN OFF-SEASON PERIOD AT DISTRITO FEDERAL SAVANNA IN 2011 IN FIRST YEAR TEST. An experiment of the first year evaluation was conduced at Embrapa Cerrados with the objective of evaluate the agronomic performance of sunflower genotypes in off-season period, and were evaluated: yield, plants height, number of broken plants, weight of a thousand seeds and days to complete flowering in 19 genetic materials between February 16th and June 15th of 2011. The average grain yield was 3390.67 kg.ha-1 and the highest yield was obtained by the genotype BRS G 30 (5489.67 kg.ha-1). The average height of plants was 175 cm, the weight of a thousand seeds was 57.03 g and the number of days to complete flowering was around 64 days.The environmental conditions expressed in off-season period at Distrito Federal savanna, in 2011, makes sunflower crop as an option in agricultural production system

Eficácia sinérgica de diferentes frações do óleo essencial de Piper aduncum L. para inseticidas utilizados no controle da lagarta-do-cartucho-do-milho.

Sinergistas como o óleo essencial de Piper aduncum L. (OEPA) são utilizados no manejo da resistência. O OEPA apresenta o dilapiol como componente majoritário, e estes compostos geralmente determinam as propriedades biológicas, sendo possível a modulação adicional de outros compostos minoritários. O objetivo desse trabalho foi o de avaliar a eficácia sinérgica de 6 frações do OEPA, para os inseticidas deltametrina e bifentrina

Linear Approach for Synchronous State Stability in Fully Connected PLL Networks

Synchronization is an essential feature for the use of digital systems in telecommunication networks, integrated circuits, and manufacturing automation. Formerly, master-slave (MS) architectures, with precise master clock generators sending signals to phase-locked loops (PLLs) working as slave oscillators, were considered the best solution. Nowadays, the development of wireless networks with dynamical connectivity and the increase of the size and the operation frequency of integrated circuits suggest that the distribution of clock signals could be more efficient if distributed solutions with fully connected oscillators are used. Here, fully connected networks with second-order PLLs as nodes are considered. In previous work, how the synchronous state frequency for this type of network depends on the node parameters and delays was studied and an expression for the long-term frequency was derived (Piqueira, 2006). Here, by taking the first term of the Taylor series expansion for the dynamical system description, it is shown that for a generic network with N nodes, the synchronous state is locally asymptotically stable

On the non-planar beta-deformed N=4 super-Yang-Mills theory

The beta-deformation is one of the two superconformal deformations of the N=4 super-Yang-Mills theory. At the planar level it shares all of its properties except for supersymmetry, which is broken to the minimal amount. The tree-level amplitudes of this theory exhibit new features which depart from the commonly assumed properties of gauge theories with fields in the adjoint representation. We analyze in detail complete one-loop amplitudes and a nonplanar two-loop amplitude of this theory and show that, despite having only N=1 supersymmetry, two-loop amplitudes have a further-improved ultraviolet behavior. This phenomenon is a counterpart of a similar improvement previously observed in the double-trace amplitude of the N=4 super-Yang-Mills theory at three and four loop order and points to the existence of additional structure in both the deformed and undeformed theories.Comment: 39 pages, 8 figure

Primeiro relato do pulgão cerataphis brasiliensis (Hempel) (Hemiptera: Aphididae) atacando mudas de duas espécies de tucumanzeiro (Astrocaryum spp.): descrição e controle.

bitstream/item/31738/1/Com-tec-223.pdfVersão eletrônica disponível em papel

The role of off-board EV battery chargers in smart homes and smart grids: operation with renewables and energy storage systems

Concerns about climate changes and environmental air pollution are leading to the adoption of new technologies for transportation, mainly based on vehicle electrification and the interaction with smart grids, and also with the introduction of renewable energy sources (RES) accompanied by energy storage systems (ESS). For these three fundamental pillars, new power electronics technologies are emerging to transform the electrical power grid, targeting a flexible and collaborative operation. As a distinctive factor, the vehicle electrification has stimulated the presence of new technologies in terms of power management, both for smart homes and smart grids. As the title indicates, this book chapter focuses on the role of off-board EV battery chargers in terms of operation modes and contextualization for smart homes and smart grids in terms of opportunities. Based on a review of on-board and off-board EV battery charging systems (EV-BCS), this chapter focus on the off-board EV-BCS framed with RES and ESS as a dominant system in future smart homes. Contextualizing these aspects, three distinct cases are considered: (1) An ac smart home using separate power converters, according to the considered technologies; (2) A hybrid ac and dc smart home with an off-board EV-BCS interfacing RES and ESS, and with the electrical appliances plugged-in to the ac power grid; (3) A dc smart home using a unified 2 off-board EV-BCS with a single interface for the electrical power grid, and with multiple dc interfaces (RES, ESS, and electrical appliances). The results for each case are obtained in terms of efficiency and power quality, demonstrating that the off-board EV-BCS, as a unified structure for smart homes, presents better results. Besides, the off-board EV-BCS can also be used as an important asset for the smart grid, even when the EV is not plugged-in at the smart home.(undefined

The Complete KLT-Map Between Gravity and Gauge Theories

We present the complete map of any pair of super Yang-Mills theories to supergravity theories as dictated by the KLT relations in four dimensions. Symmetries and the full set of associated vanishing identities are derived. A graphical method is introduced which simplifies counting of states, and helps in identifying the relevant set of symmetries.Comment: 41 pages, 16 figures, published version, typos corrected, references adde