Frontal cortex differentiates between free and imposed target selection in multiple-target search

Cognitive control can involve proactive (preparatory) and reactive (corrective) mechanisms. Using a gaze-contingent eye tracking paradigm combined with fMRI, we investigated the involvement of these different modes of control and their underlying neural networks, when switching between different targets in multiple-target search. Participants simultaneously searched for two possible targets presented among distractors, and selected one of them. In one condition, only one of the targets was available in each display, so that the choice was imposed, and reactive control would be required. In the other condition, both targets were present, giving observers free choice over target selection, and allowing for proactive control. Switch costs emerged only when targets were imposed and not when target selection was free. We found differential levels of activity in the frontoparietal control network depending on whether target switches were free or imposed. Furthermore, we observed core regions of the default mode network to be active during target repetitions, indicating reduced control on these trials. Free and imposed switches jointly activated parietal and posterior frontal cortices, while free switches additionally activated anterior frontal cortices. These findings highlight unique contributions of proactive and reactive control during visual search

The Near-Horizon Limit of the Extreme Rotating d=5 Black Hole as a Homogenous Spacetime

We show that the spacetime of the near-horizon limit of the extreme rotating d=5 black hole, which is maximally supersymmetric in N=2,d=5 supergravity for any value of the rotation parameter j in [-1,1], is locally isomorphic to a homogeneous non-symmetric spacetime corresponding to an element of the 1-parameter family of coset spaces SO(2,1)x SO(3)/SO(2)_j in which the subgroup SO(2)_j is a combination of the two SO(2) subgroups of SO(2,1) and SO(3).Comment: Some points clarified and misprints corrected. Version to be published in Classical and Quantum Gravit

Dise?o y renovaci?n del parque centenario y la concha acustica "Garz?n y Collazos" para la ciudad de Ibagu?

131 p. Recurso Electr?nicoEl proyecto abarca una propuesta al parque Centenario de dise?o y renovaci?n en un ?rea aproximada de 56418 metros cuadrados en ?l que se adelanta un diagnostico al centro hist?rico de la ciudad y sus alrededores para poder interpretar las condiciones ambientales, urbanas, sociales y arquitect?nicas, y desarrollar as? una propuesta que involucre la recuperaci?n del centro hist?rico de la ciudad al integrar la propuesta de parque lineal que devuelva la calidad ambiental perdida y la zonificaci?n en las ?reas de vegetaci?n existente, al conservar elementos de car?cter patrimonial y luego se hace un inventario del estado actual de los elementos arquitect?nicos, mobiliario, materiales, etc. se interpretan las necesidades de integrar la quebrada la Pioja al generar ejes paralelos a la misma y que marcan recorridos y zonas de concentraci?n. Se retoman caracter?sticas topogr?ficas del terreno y se insertan dentro del dise?o urbano tanto en parque, paisaje y proyecto puntual arquitect?nico. Se logra un dise?o acorde con la tipolog?a de accesos. Las curvas y diagonales ser?n las formas geom?tricas principales en las representaciones en todo el proyecto. la curva ser? el elemento estructurador de los espacios, Se involucran el agua y los senderos en adoqu?n y concreto cepillado, asociados a los recorridos que buscan espacios de contemplaci?n, permanencia, recreaci?n pasiva, ?reas de actividad m?ltiple, culturales, educativas y de descanso, incluyendo un proyecto arquitect?nico; que en este caso es un centro de bellas artes el para complementar las actividades culturales y art?sticas.The project includes a proposal to the Centennial park of design and renovation in an approximate area of 254,000 square meters in which a diagnosis is advanced to the historic center of the city and its surroundings to be able to interpret the environmental, urban, social and architectural conditions, and To develop a proposal that involves the recovery of the historic center of the city by integrating the linear park proposal that returns the lost environmental quality and zoning in the existing vegetation areas, conserving heritage elements and then making an inventory of the Current state of the architectural elements, furniture, materials, etc. Are interpreted the needs to integrate the ravine the Pioja by generating axes parallel to it and that mark routes and zones of concentration. Topographic characteristics of the terrain are taken up and inserted into the urban design, both in the park, landscape and architectural design. A design is achieved according to the type of access. The curves and diagonals will be the main geometric forms in the representations throughout the project. The curve will be the structuring element of the spaces. Water and pavements are involved in cobblestone and brushed concrete, associated to the paths that seek spaces of contemplation, permanence, passive recreation, multiple activity areas, cultural, educational and rest, Including an architectural project; Which in this case is a center of fine arts to complement cultural and artistic activities. Keywords: Design, renovation, integrate, generate, conserve

Tipologia textual una herramienta para la producci?n escritural en los estudinates de los grados quinto y sexto de educaci?n b?sica del colegio parroquial de Nuestra Se?ora

171 p. Recurso Electr?nicoEl proyecto de investigaci?n se desarroll? con los estudiantes del Grado quinto y sexto del Colegio Parroquial de Nuestra Se?ora, donde se identific? un alto grado de dificultad en la producci?n escrita, puesto que los estudiantes tienden a escribir oraciones o fragmentos, sin incorporar elementos sint?cticos de concordancia, cohesi?n e intencionalidad comunicativa en sus producciones. Por esta raz?n, el proyecto contribuye al desarrollo de la producci?n textual de los estudiantes para que produzcan diferentes tipos de textos, de tal manera que asuman la escritura como un proceso que les permite comprender e interpretar el mundo que les rodea y puedan utilizarla en cualquier contexto en particular donde se desenvuelvan. Para diversos autores (Daniel Cassany, Victor Miguel Ni?o y Van Dijk), la escritura es algo m?s que un simple artefacto mec?nico. Se considera el m?s grande invento manual-intelectual creado por el hombre, realizado manualmente, o por medios impresos o electr?nicos. Frente a esta mirada de la escritura se hace evidente la necesidad de continuar produciendo herramientas pedag?gicas que permitan resolver los m?ltiples problemas de la ense?anza de la lengua escrita. Con esta finalidad, los resultados de este trabajo investigativo brindaron los siguientes aportes. Los ni?os y las ni?as se acercaron al mundo de la escritura de una manera significativa y agradable, creando escritos a partir de las tipolog?as textuales. El dise?o metodol?gico se desarroll? en tres etapas: Observaci?n y diagn?stico, implementaci?n y evaluaci?n, teniendo como base la implementaci?n los talleres guiados como estrategia para fortalecer los procesos de escritura por medio de diferentes textosThe project of investigation developed with the students of the fifth and sixth Degree of the Parochial College of Our Lady, where a high degree of difficulty was identified in the written production, since the students tend to write prayers or fragments, without incorporating syntactic elements of conformity, cohesion and communicative premeditation in his productions. For this reason, the project tried to contribute to the development of the textual production of the students in order that they produce different types of texts, in such a way that they assume the writing as a process that allows them to understand and to interpret the world that they makes a detour and could use it in any context especially where they are unrolled. For diverse authors (Daniel Cassany, Victor Miguel Ni?o y Van Dijk), the writing is something more than a simple mechanical appliance. It is considered to be the biggest manual - intellectual invention created by the man, realized manually, or for printed or electronic means. Opposite to this look of the writing the need to continue becomes evident producing pedagogic tools that allow solving the multiple problems of the education of the written language. With this purpose, the results of this work investigative offered the following contributions. The children and the girls approached the world of the writing of a significant and agreeable way, creating writings from the textual typologies. The methodological design developed in three stages: Observation and diagnosis, implementation and evaluation, taking the implementation as a base the workshops guided as strategy to strengthen the processes of writing by means of different texts. Keywords: Writing, textual production, typologies textual, holding a permit workshop

A Note on Lie-Lorentz Derivatives

The definition of ``Lie derivative'' of spinors with respect to Killing vectors is extended to all kinds of Lorentz tensors. This Lie-Lorentz derivative appears naturally in the commutator of two supersymmetry transformations generated by Killing spinors and vanishes for Vielbeins. It can be identified as the generator of the action of isometries on supergravity fields and its use for the calculation of supersymmetry algebras is revised and extended.Comment: Latex2e, 9 pages, AMS font

Fate of drugs during wastewater treatment

This is the post-print version of the final paper published in TrAC Trends in Analytical Chemistry. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2013 Elsevier B.V.Recent trends in the determination of pharmaceutical drugs in wastewaters focus on the development of rapid multi-residue methods. This review addresses recent analytical trends in drug determination in environmental matrices used to facilitate fate studies. Analytical requirements for further fate evaluation and tertiary process selection and optimization are also discussed.EPSRC, Northumbrian Water, Anglian Water, Severn Trent Water, Yorkshire Water, and United Utilities

On d=4,5,6 Vacua with 8 Supercharges

We show how all known N=2, d=4,5,6 maximally supersymmetric vacua (Hpp-waves and aDSxS solutions) are related through dimensional reduction/oxidation preserving all the unbroken supersymmetries. In particular we show how the N=2, d=5 family of vacua (which are the near-horizon geometry of supersymmetric rotating black holes) interpolates between aDS_2xS^3 and aDS_3xS^2 in parameter space and how it can be dimensionally reduced to an N=2, d=4 dyonic Robinson-Bertotti solution with geometry aDS_2xS^2 and oxidized to an N=2, d=6 solution with aDS_3xS^3 geometry (which is the near-horizon of the self-dual string).Comment: Latex2e, 19 pages, 1 figure. v2: typos corrected, refs. added. v3: very minor corrections, more refs. added, version to be published in Classical and Quantum Gravit