Observing Grasping Actions Directed to Emotion-Laden Objects: Effects upon Corticospinal Excitability

The motor system is recruited whenever one executes an action as well as when one observes the same action being executed by others. Although it is well established that emotion modulates the motor system, the effect of observing other individuals acting in an emotional context is particularly elusive. The main aim of this study was to investigate the effect induced by the observation of grasping directed to emotion-laden objects upon corticospinal excitability (CSE). Participants classified video-clips depicting the right-hand of an actor grasping emotion-laden objects. Twenty video-clips differing in terms of valence but balanced in arousal level were selected. Motor evoked potentials (MEPs) were then recorded from the first dorsal interosseous using transcranial magnetic stimulation (TMS) while the participants observed the selected emotional video-clips. During the video-clip presentation, TMS pulses were randomly applied at one of two different time points of grasping: (1) maximum grip aperture, and (2) object contact time. CSE was higher during the observation of grasping directed to unpleasant objects compared to pleasant ones. These results indicate that when someone observes an action of grasping directed to emotion-laden objects, the effect of the object valence promotes a specific modulation over the motor system.Fil: Nogueira Campos, Anaelli A.. Universidade Federal de Juiz de Fora; BrasilFil: Saunier, Ghislain. Universidade Federal do Pará; BrasilFil: Della Maggiore, Valeria Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: De Oliveira, Laura A. S.. Centro Universitário Augusto Motta; BrasilFil: Rodrigues, Erika C.. Centro Universitário Augusto Motta; BrasilFil: Vargas, Claudia D.. Universidade Federal do Rio de Janeiro; Brasi

Coherent control of injection currents in high-quality films of Bi2Se3

Films of the topological insulator Bi2Se3 are grown by molecular beam epitaxy with in-situ reflection high-energy electron diffraction. The films are shown to be high-quality by X-ray reflectivity and diffraction and atomic-force microscopy. Quantum interference control of photocurrents is observed by excitation with harmonically related pulses and detected by terahertz radiation. The injection current obeys the expected excitation irradiance dependence, showing linear dependence on the fundamental pulse irradiance and square-root irradiance dependence of the frequency-doubled optical pulses. The injection current also follows a sinusoidal relative-phase dependence between the two excitation pulses. These results confirm the third-order nonlinear optical origins of the coherently controlled injection current. Experiments are compared to a tight-binding band structure to illustrate the possible optical transitions that occur in creating the injection current.Comment: 11 pages, 3 figure, journal articl

Impactos genéticos da introdução de peixes em águas continentais.

bitstream/CPAP/56306/1/ADM107.pdfFormato Eletrônico

Parallel Evolution of Quasi-separatrix Layers and Active Region Upflows

Persistent plasma upflows were observed with Hinode's EUV Imaging Spectrometer (EIS) at the edges of active region (AR) 10978 as it crossed the solar disk. We analyze the evolution of the photospheric magnetic and velocity fields of the AR, model its coronal magnetic field, and compute the location of magnetic null-points and quasi-sepratrix layers (QSLs) searching for the origin of EIS upflows. Magnetic reconnection at the computed null points cannot explain all of the observed EIS upflow regions. However, EIS upflows and QSLs are found to evolve in parallel, both temporarily and spatially. Sections of two sets of QSLs, called outer and inner, are found associated to EIS upflow streams having different characteristics. The reconnection process in the outer QSLs is forced by a large-scale photospheric flow pattern which is present in the AR for several days. We propose a scenario in which upflows are observed provided a large enough asymmetry in plasma pressure exists between the pre-reconnection loops and for as long as a photospheric forcing is at work. A similar mechanism operates in the inner QSLs, in this case, it is forced by the emergence and evolution of the bipoles between the two main AR polarities. Our findings provide strong support to the results from previous individual case studies investigating the role of magnetic reconnection at QSLs as the origin of the upflowing plasma. Furthermore, we propose that persistent reconnection along QSLs does not only drive the EIS upflows, but it is also responsible for a continuous metric radio noise-storm observed in AR 10978 along its disk transit by the Nan\c{c}ay Radio Heliograph.Comment: 29 pages, 10 figure

Resposta de plantas milho crescidas em solo contendo Clethodim.

O uso prolongado de um mesmo herbicida ou similar, no manejo de plantas daninhas pode ocasionar o surgimento de biótipos resistentes e favorecer o efeito residual destes no solo. O herbicida clethodim, utilizado no manejo de daninhas em várias culturas, principalmente na soja, foi testado para se avaliar o efeito residual em uma cultura sucessora de milho. Dois experimentos foram conduzidos no laboratório na Embrapa Milho e Sorgo, Sete Lagoas, MG, utilizando-se sementes de milho variedade Syngenta 7205 TL TG, em vasos com capacidade de 500ml, preenchidos com um solo classificado como Latossolo Vermelho distrófico, textura argilosa (LVd), adubado de acordo com análise do solo. O herbicida foi incorporado ao solo em equivalência de doses de: 0,1; 0,2; 0,40; 0,8; 1,60 e 3,2 ppm. Adotou-se delineamento estatístico inteiramente casualizado com quatro repetições. Foram avaliados: altura das plantas aos 3, 5, 7 e 14 dias após a emergência (DAE) e fitotoxidade visual e acumulo de biomassa seca aos 14 DAE. A fitotoxicidade visual, altura de plantas e acúmulo de biomassa seca alcançaram índices de redução de 50% quando da presença aproximada do equivalente a 0,39 ppm de clethodim no solo. Os resultados demonstraram que resíduos da aplicação do herbicida clethodim podem ocasionar reduções significativas no crescimento inicial de plantas de milho. Estudos relacionados a épocas de plantio e concentrações de clethodim no solo estão sendo realizados para melhor entender o efeito residual deste herbicida na cultura do milho.CBCPD

Gause's exclusion principle revisited: artificial modified species and competition

Gause's principle of competition between two species is studied when one of them is sterile. We study the condition for total extinction in the niche, namely, when the sterile population exterminates the native one by an optimal use of resources. A mathematical Lotka-Volterra non linear model of interaction between a native and sterile species is proposed. The condition for total extinction is related to the initial number $M_{o}$ of sterile individuals released in the niche. In fact, the existence of a critical sterile-population value $M_{c}$ is conjectured from numerical analysis and an analytical estimation is found. When spatial diffusion (migration) is considered a critical size territory is found and, for small territory, total extinction exist in any case. This work is motived by the extermination agriculture problem of fruit flies in our region.Comment: 11 pages. Published in Jour.Phys.A Math.Gen. 33, 4877 (2000

Towards a Business Model Framework to Increase Collaboration in the Freight Industry

Collaboration in the freight industry has not been widely adopted mainly due to the perceived barriers in competition resulting in a lack of trust among fleet operators. Collaboration in this sector has significant benefits, including the reduction of empty running, operating costs (OPEX) and greenhouse gas emissions (GHG) resulting in greater utilisation of existing logistics assets. A review of the literature to establish the critical aspects of freight collaboration was undertaken, as well as analyses of published case studies and European Union (EU)-funded projects. The critical aspects and barriers identified include: revenue sharing; compliance with competition law; process synchronization; organisational and systems interoperability; different forms of collaboration from a physical and coordination structure perspective; and strategies for collaboration. To facilitate collaboration a freight collaborative business model (FCBM) framework that highlights problematic areas in freight collaboration is proposed to support standardizing collaborative practices in the freight industry. Three published freight industry collaboration business cases were evaluated against the model. The business model framework is intended as a tool to be used to compare different business models and identify the best innovations to help facilitate collaborative practices. The freight collaboration business model was applied to the Freight Share Lab research project in order to demonstrate the concept and investigate whether efficiency can be unlocked through deployment of a dynamic data and asset sharing platform to enable route and load optimization across multiple fleets of freight vehicles, rail freight wagons and containers