WorldWideScience

Sample records for debe saber antes

  1. Lo que usted debe saber acerca del dengue

    OpenAIRE

    Vélez, Juan David; Fundación Valle de Lili; Salazar, Juan Carlos; Rosso Suárez, Fernando

    1998-01-01

    Epidemiología del dengue/Transmisión/Presentación clínica/Síntomas en niños/Diagnostico de laboratorio/Dengue clásico/Dengue hemorrágico/Dengue hemorrágico con choque/ ¿Qué es dengue hemorrágico?/ ¿Cuál es la diferencia entre dengue hemorrágico y dengue clásico?/ ¿Qué son las plaquetas?/ ¿Qué puedo hacer para prevenir el dengue?/ ¿Cuándo debo consultar?/ ¿Cuándo se debe hacer un hemograma?/ ¿Cuándo se debe hospitalizar un paciente con dengue?

  2. Saberes docentes da dança

    Directory of Open Access Journals (Sweden)

    Silvia Camara Soter da Silveira

    2016-12-01

    Full Text Available Este artigo trata do tema saberes docentes e busca sua relação com o ensino da dança na escola. A categoria saber docente tornou-se central no campo da formação de professores a partir dos anos 1990 no Brasil. Neste trabalho, o saber docente é abordado através de dois autores que se dedicaram ao tema: Maurice Tardif (2012 e Selma Garrido Pimenta (2012, na busca de refletir sobre as especificidades do saber docente daquele que ensina dança na escola. O saber docente se constitui, de uma parte, na formação inicial e contínua em instituições de formação de professores e, de outra parte, se desenvolve ao longo da vida dos estudantes e professores, em contextos distintos destas instituições, nas vivências destes professores antes da chegada à formação inicial, nas marcas que a escolarização deixou, na articulação do que aprendem nos cursos de formação de professores com a realidade da escola e, também, pela própria prática docente no início da atividade profissional, no contexto da escola, através das trocas com seus pares. No caso da dança, no saber docente se mesclam saberes constituídos no ensino formal como no não formal, que na trajetória dos docentes de dança parece ter um papel importante.

  3. Transferência: amor ao saber Transference: the love to know

    Directory of Open Access Journals (Sweden)

    Gilberto Gênova Gobbato

    2001-06-01

    Full Text Available Procura-se evidenciar um novo direcionamento para a questão do amor de transferência com o ensino de Jacques Lacan. Trata-se, antes de mais nada, do questionamento do lugar do analista para responder a esse amor. A tese de Lacan é de que esse amor é endereçado ao saber: o analisando coloca o analista na posição de sujeito suposto saber, de um saber consistente, de um saber que sabe. Entretanto, da perspectiva do analista o saber não sabe. O analista deve conduzir a análise visando esse não saber como verdade.The article tries to make evident a new direction in the question of transference love according to Lacan's teaching. At first, it deals with the question of the analyst's position in order to answer to this love. Lacan's thesis relies on the fact that this love is addressed to knowledge. Based on that, the analyzand puts the analyst in the position of a subject supposed to know, supposed to have a consistent knowledge, a knowledge that knows. However, from the analyst's point of view, knowledge does not know. Having this in mind as the truth, the analyst must analyze his patient.

  4. El proceso de construcción del saber pedagógico en Educación Matemática

    OpenAIRE

    Sotos Serrano, María Antonia; López Esteban, María Carmen

    2015-01-01

    Presentamos el proceso de construcción del saber pedagógico de la profesora M. Antònia Canals i Tolosa, utilizando el modelo de los saberes docentes de Tardif. Dicho modelo destaca la importancia de los saberes experienciales y del proceso de reflexión compartida, necesario para construir el saber pedagógico. En el caso de la profesora Canals, la importancia de esos dos elementos es evidente, y su análisis permite indagar en la historia de la educación en general, y de la educación matemática...

  5. SABER Optical Design

    International Nuclear Information System (INIS)

    Erickson, R

    2006-01-01

    SABER, the South Arc Beam Experimental Region, is a proposed new beam line facility designed to replace the Final Focus Test Beam at SLAC. In this paper, we outline the optical design features and beam parameters now envisioned for SABER. A magnetic chicane to compress positron bunches for SABER and a bypass line that could transport electrons or positrons from the two-thirds point of the linac to SABER, bypassing the LCLS systems, are also discussed

  6. Editorial. Fundamentos para una Pedagogía del Saber y del No Saber

    Directory of Open Access Journals (Sweden)

    Agustín de la Herrán Gascón

    2018-03-01

    Full Text Available El libro titulado “Fundamentos para una Pedagogía del Saber y del No Saber” (Herrán Gascón, A. de la, São Paulo: Edições Hipótese, 2018 sirve el propósito de contribuir a la necesaria renovación radical de la Pedagogía y de la Didáctica, para favorecer una educación y una formación más coherentes y completas con base en la conciencia. Se apoya en la tesis de que la herencia de Sócrates es limitante para la educación, y condiciona el constructo ‘formación’ y la evolución de la Pedagogía y de la Didáctica. Hoy ambas disciplinas son parcialmente válidas, porque su base, erigida sobre el aprender, el conocer y sobre una idea parcial de formación, es incompleta. Su énfasis en el saber –léase no sólo aprendizaje de saberes, sino el saber pensar, saber sentir, saber ser, saber convivir, saber hacer, saber gestionar las emociones, saber contenidos instructivos u orientadores, saber competencias, etc. -limita la educación y la formación. No parecen darse cuenta de esta posibilidad, al parecer, los organismos internacionales de educación, las leyes y los sistemas educativos, ni la mayor parte de pedagogos e investigadores de la educación. Históricamente, se ha arrastrado en estas disciplinas un sesgo, al no incorporarse la enseñanza de grandes pedagogos o maestros de la formación de Oriente, con una mirada diferente. Nuestra posición es que sin la comprensión que ofrecen –y que al parecer se ignora por el ‘occidentalismo’ (o ismo de Occidente en que vivimos, potenciado por la globalización,- la educación no puede estar completa, ni puede comprenderse en absoluto.

  7. "Saber" and "Conocer."

    Science.gov (United States)

    Taylor, Kathy

    1985-01-01

    Attempts to redefine the meaning of the two Spanish verbs "saber" and "conocer" and explores some possible extralinguistic factors affecting their usage. Shows that "conocer" represents knowledge which is firsthand and that this type of knowledge is a building block for the more thorough, systematic knowledge represented by "saber." (SED)

  8. Cáncer colorrectal: Lo que debe saber (Colorectal Cancer - What You Need to Know)

    Centers for Disease Control (CDC) Podcasts

    2011-07-05

    Este podcast se basa en un informe de Vital Signs, publicado por los CDC en julio del 2011. El cáncer colorrectal causa todos los años la muerte de unos 50,000 hombres y mujeres. ¡Las pruebas de detección pueden salvar vidas! Estas pruebas pueden encontrar tejido anormal que puede ser extraído antes de que se convierta en cáncer y pueden encontrar el cáncer en su etapa inicial, cuando es más fácil de tratar. Si usted tiene 50 años o más, hable con su médico y hágase las pruebas de detección del cáncer colorrectal.  Created: 7/5/2011 by Centers for Disease Control and Prevention (CDC).   Date Released: 8/1/2011.

  9. Saberes docentes da dança

    OpenAIRE

    Silvia Camara Soter da Silveira; Monique Andries Nogueira

    2016-01-01

    Este artigo trata do tema saberes docentes e busca sua relação com o ensino da dança na escola. A categoria saber docente tornou-se central no campo da formação de professores a partir dos anos 1990 no Brasil. Neste trabalho, o saber docente é abordado através de dois autores que se dedicaram ao tema: Maurice Tardif (2012) e Selma Garrido Pimenta (2012), na busca de refletir sobre as especificidades do saber docente daquele que ensina dança na escola. O saber docente se constitui, de uma par...

  10. Formación de saberes políticos: aportes de investigaciones psicológicas

    OpenAIRE

    Lenzi, Alicia; D'Avirro, María Julieta; Pataro, María Alejandra; Areste, María Silvina

    2007-01-01

    Se examina la cuestión de los saberes políticos en niños, jóvenes y adultos, desde las contribuciones de investigaciones de la psicología del desarrollo y la psicología educacional, con ciertas referencias a la psicología social y política. Subyace a esta cuestión el polémico concepto de ciudadanía y concepciones divergentes acerca de la formación ciudadana y sus prácticas. La literatura especializada revela una creciente preocupación por la formación de los futuros ciudadanos ante la mundial...

  11. ACCIONES DOCENTES: SABERES EN PUGNA

    Directory of Open Access Journals (Sweden)

    MARCELA GAETE VERGARA

    2011-01-01

    Full Text Available El artículo presenta algunas reflexiones en relación a la tríada saber, discurso y acción docente, que constituye parte de los resultados de una investigación doctoral, cuyo propósito es comprender el sentido, que han construido los profesores de filosofía en relación a la enseñanza y el aprendizaje de la disciplina y que subyace en la configuración de un saber para la escuela. La investigación de carácter cualitativa y hermenéutica utiliza como técnicas de recolección de información la entrevista en profundidad y análisis de materiales didácticos de autoría de los docentes participantes del estudio. Los principales resultados indican que existe una tensión permanente entre los saberes docentes provenientes de los dispositivos pedagógicos institucionalizados que obedecen una racionalidad instrumental con aquellos saberes que son configurados desde la experiencia íntima con la disciplina y su enseñanza. Tal tensión, evidencia que los docentes no son simples aplicadores de teorías o currículos sino que van constituyendo saberes no legitimados desde las formaciones discursivas dominantes. No obstante, tales saberes se mantienen en la esfera privada, pues la escuela y la formación docente no dan espacios para que los maestros puedan narrar sus acciones, y con ello, constituirse en sujetos políticos.

  12. Performance analysis in saber.

    Science.gov (United States)

    Aquili, Andrea; Tancredi, Virginia; Triossi, Tamara; De Sanctis, Desiree; Padua, Elvira; DʼArcangelo, Giovanna; Melchiorri, Giovanni

    2013-03-01

    Fencing is a sport practiced by both men and women, which uses 3 weapons: foil, épée, and saber. In general, there are few scientific studies available in international literature; they are limited to the performance analysis of fencing bouts, yet there is nothing about saber. There are 2 kinds of competitions in the World Cup for both men and women: the "FIE GP" and "A." The aim of this study was to carry out a saber performance analysis to gain useful indicators for the definition of a performance model. In addition, it is expected to verify if it could be influenced by the type of competition and if there are differences between men and women. Sixty bouts: 33 FIE GP and 27 "A" competitions (35 men's and 25 women's saber bouts) were analyzed. The results indicated that most actions are offensive (55% for men and 49% for women); the central area of the piste is mostly used (72% for men and 67% for women); the effective fighting time is 13.6% for men and 17.1% for women, and the ratio between the action and break times is 1:6.5 for men and 1:5.1 for women. A lunge is carried out every 23.9 seconds by men and every 20 seconds by women, and a direction change is carried out every 65.3 seconds by men and every 59.7 seconds by women. The data confirm the differences between the saber and the other 2 weapons. There is no significant difference between the data of the 2 different kinds of competitions.

  13. Fundamentos del saber administrativo

    OpenAIRE

    Paola Podestá Correa; Juan Carlos Jurado Jurado

    2005-01-01

    El presente texto tiene por objetivo delimitar, de manera general, algunos de los conceptos más importantes del saber administrativo; en primera instancia, práctica administrativa y saber administrativo. Estos conceptos están ligados con los que en el texto se denominan fundamentos de la administración, estableciendo consensos sobre algunas expresiones comunes en el lenguaje administrativo, y contribuyendo a la comprensión de estos temas para los estudiantes de los primeros niv...

  14. SABER-School Finance: Data Collection Instrument

    Science.gov (United States)

    King, Elizabeth; Patrinos, Harry; Rogers, Halsey

    2015-01-01

    The aim of the SABER-school finance initiative is to collect, analyze and disseminate comparable data about education finance systems across countries. SABER-school finance assesses education finance systems along six policy goals: (i) ensuring basic conditions for learning; (ii) monitoring learning conditions and outcomes; (iii) overseeing…

  15. La mercantilización del saber

    Directory of Open Access Journals (Sweden)

    Mario Solano Solano

    2007-05-01

    Full Text Available En este artículo se establece que el cálculo económico que rige la gestión económica típica del capitalismo se irradia también a la esfera de la producción, distribución, circulación y consumo del saber. Por ello, la maximización del beneficio llega a ser un impulso fundamental en la economía del saber, particularmente en las economías capitalistas más desarrolladas. Esta lógica es la que subyace a la creciente privatización y mercantilización del saber, la cual adquiere múltiples manifestaciones, entre ellas la incrementada comercialización de los productos culturales (libros, discos de música y de video, pero también de la creciente ingerencia de la lógica de la acumulación capitalista en los procesos más específicos de la dinámica del saber, como lo son la evaluación de la investigación y su transmisión mediante la educación. Así, en la llamada “condición posmoderna” el saber deviene en una simple mercancía que se produce por el beneficio económico o el incremento de poder a quien la financie y no por un compromiso con la verdad. Esta mercantilización del saber se une a las gravísimas amenazas (devastación ecológica, desigualdad social que pesan sobre la simple posibilidad de sobrevivencia de la especie humana sobre el planeta Tierra.

  16. SABER-School Finance : Data Collection Instrument

    OpenAIRE

    World Bank

    2015-01-01

    The aim of the SABER-school finance initiative is to collect, analyze and disseminate comparable data about education finance systems across countries. SABER-school finance assesses education finance systems along six policy goals: (i) ensuring basic conditions for learning; (ii) monitoring learning conditions and outcomes; (iii) overseeing service delivery; (iv) budgeting with adequate an...

  17. A EXPERIÊNCIA DE CONCILIAÇÃO DOS SABERES PRODUZIDOS EM SITUAÇÃO DE TRABALHO COM OS SABERES PRODUZIDOS NA ACADEMIA: O CURSO CEF-PROFAE/UFMG

    OpenAIRE

    Schwartz, Yves; Silva, Jurandir Soares da

    2010-01-01

    A pesquisa se desenvolve no departamento de Ergologia da Universidade de Aix-En-Provence e está em fase de finalização. A questão principal é compreender a forma como as trabalhadoras-alunas atendentes de enfermagem do CEFPROFAE/CP-FaE-UFMG, interrogaram e combinaram os saberes disciplinares e os saberes desenvolvidos nas atividades. Saberes estes construídos em situação de trabalho e em outros espaços de socialização (saberes em aderência) com os saberes acadêmicos (saberes em desaderência)....

  18. Bigger helpers in the ant Cataglyphis bombycina: increased worker polymorphism or novel soldier caste?

    Directory of Open Access Journals (Sweden)

    Mathieu Molet

    Full Text Available The mechanisms by which development favors or constrains the evolution of new phenotypes are incompletely understood. Polyphenic species may benefit from developmental plasticity not only regarding ecological advantages, but also potential for evolutionary diversification. For instance, the repeated evolution of novel castes in ants may have been facilitated by the existence of alternative queen and worker castes and their respective developmental programs.Cataglyphis bombycina is exceptional in its genus because winged queens and size-polymorphic workers occur together with bigger individuals having saber-shaped mandibles. We measured seven body parts in more than 150 individuals to perform a morphometric analysis and assess the developmental origin of this novel phenotype.Adults with saber-shaped mandibles differ from both workers and queens regarding the size of most body parts. Their relative growth rates are identical to workers for some pairs of body parts, and identical to queens for other pairs of body parts; critical sizes differ in all cases.Big individuals are a third caste, i.e. soldiers, not major workers. Novel traits such as elongated mandibles are combined with a mix of queen and worker growth rates. We also reveal the existence of a dimorphism in the queen caste (microgynes and macrogynes. We discuss how novel phenotypes can evolve more readily in the context of an existing polyphenism. Both morphological traits and growth rules from existing queen and worker castes can be recombined, hence mosaic phenotypes are more likely to be viable. In C. bombycina, such a mosaic phenotype appears to function both for defense (saber-shaped mandibles and fat storage (big abdomen. Recycling of developmental programs may have contributed to the morphological diversity and ecological success of ants.

  19. La terrible soledad del saber The terrible solitude of knowledge

    Directory of Open Access Journals (Sweden)

    Restrepo Gabriel

    1999-12-01

    Full Text Available Este ensayo glosa uno de los frentes de trabajio mas atines a Jesús A. Bejarano: la historia y el análisis de la ciencia y de las profesiones, en este caso de la economía. El eje de estos comentarios es la relación entre ciencia económica y poder, partiendo de la queja de Bejarano ante la falsa de reflexión critica sobre este tema, y considerando además su parabolavital como un ejemplode tensión dramatica entre saber y poder, dada la estructura política de Colombia.This essay discusses one of Bejarano's favorite fields of study: the history and analysis of science, as applied to economics. The main line of argument is determined by the relation between economic science and power, which in Bejarano' s opinion had not been adequately considered. His life is taken as a parable of the dramatic tension between knowledge and power within the political structure of Colombia.

  20. Saberes e práticas de acompanhantes sobre complicações respiratórias pós-cirúrgicas no idoso, compartilhados com a enfermeira Conocimientos y prácticas de acompañantes sobre complicaciones respiratorias posquirúrgicas en ancianos, compartidas con la enfermera Knowledge and experiences of caregivers for post-surgical respiratory complications in elderly people, shared with the nurse

    Directory of Open Access Journals (Sweden)

    Maria da Luz Ferreira Xavier

    2012-09-01

    Full Text Available Pesquisa convergente-assistencial cujo objetivo foi analisar saberes e práticas de acompanhantes voltados à prevenção de complicações respiratórias pós-cirúrgicas no idoso, com vistas a traçar um plano de cuidados a ser implementado para esses clientes. As bases teórico-conceituais pautaram-se na pedagogia problematizadora de Freire. Os sujeitos foram 14 acompanhantes de idosos em pré-operatório. Utilizou-se técnica de entrevista individual e observação participante, e análise de conteúdo temática. Os resultados revelaram que as acompanhantes acumulam saberes, acerca de cuidados básicos no pós-operatório, capazes de prevenir problemas respiratórios. Pela dialogicidade construiu-se um plano de cuidados compartilhado a ser realizado com o idoso, consequência da integração de saberes e práticas dos acompanhantes com os da enfermeira-pesquisadora na visita pré-operatória. Resultaram novas ou revisitadas práticas, culminando em um cuidado congruente às reais necessidades dos clientes e seus acompanhantes, tornando-os parceiros no processo de cuidar.Investigación convergente y asistencial, con objetivo de analizar los conocimientos y prácticas de acompañantes dirigidos a la prevención de complicaciones respiratorias posquirúrgicas en el anciano, a fin de elaborar un plan de cuidados para ser implementado con estos clientes. Las bases teórica y conceptual se pautaron en la pedagogía problematizada de Paulo Freire. Los sujetos fueron 14 acompañantes de clientes ancianos en el período preoperatorio. Se utilizó la técnica de entrevistas individuales y de observación participante y análisis de contenido temático. Los resultados revelaron que las acompañantes acumulan saber, acerca de cuidados básicos en el pos-operatorio, capaces de prevenir problemas respiratorios. A partir de conversaciones, se construyó un plan de cuidados compartido a ser realizado con el anciano, resultante de la integración de

  1. Eutonia "O saber do corpo"

    OpenAIRE

    Miriam Dascal

    2005-01-01

    Resumo: Nesta dissertação realizo uma reflexão sobre os conceitos teóricos e práticos que fundamentam o trabalho de Eutonia e apresento uma pesquisa que elaborei a partir destes conceitos. A Eutonia propõe um campo metodológico que envolve o autoconhecimento do próprio corpo e de sua atividade de movimento. Estabelece um campo investigatório no qual revelam-se conhecimentos, que denomino "o saber do corpo". Refletindo sobre este "saber", reconheço e o relaciono com os pressupostos estabeleci...

  2. Sarah J. Hale High School-Project SABER.

    Science.gov (United States)

    Rosenblatt, Harold

    Project SABER, which operated in Sarah J. Hale High School in South Brooklyn, New York, consisted of bilingual instructional and supportive services to 9th and 10th grade Spanish language students. Students received bilingual instruction in social studies, science, math, and Spanish. All the SABER students received English as a second language…

  3. Saber escuchar: Un intangible valioso

    Directory of Open Access Journals (Sweden)

    Alexis Codina

    2007-07-01

    Full Text Available La habilidad de “saber escuchar” es más difícil de encontrar y desarrollar que la de ser “buen comunicador”, pero proporciona más autoridad e influencia que esta última, dicen los especialistas. Si Ud. es buen comunicador, pero no sabe escuchar, corre el riesgo de comunicar en forma elocuente cosas que no le interesan a la gente. Entre las habilidades que caracterizan a directivos y profesionales exitosos se encuentra la de saber escuchar, su ausencia es uno de los factores generadores de conflictos. Entre los tópicos principales que estudian los especialistas en este tema y que son comentados en este artículo están: los beneficios de saber escuchar, conductas no productivas cuando escuchamos, razones que nos impiden escuchar adecuadamente, lugares desde los que escuchamos, los objetivos de la comunicación y cómo tratarlos así como propuestas de comportamientos y prácticas para desarrollar esta habilidad, tan importante para las relaciones interpersonales.

  4. La gerencia del saber pedagógico en el ambiente universitario

    Directory of Open Access Journals (Sweden)

    Meuris Basabe

    2004-05-01

    Full Text Available El propósito del estudio es reflexionar sobre cómo gerenciar el saber pedagógico en ambientes universitarios. Se sustentó metodológicamente en un estudio teórico documental, haciendo un análisis sobre la Sociedad del conocimiento, la gerencia del conocimiento y el saber pedagógico. Como resultado se presentan algunas reflexiones que conducen a la toma de decisiones para gerenciar el saber pedagógico. Se concluye que existe la necesidad de docentes con características muy distintas a las tradicionales, que permita el análisis critico-reflexivo del saber y el hacer. Es decir, docentes que gerencien los procesos para la construcción del saber pedagógico.

  5. The use of the saber in the army of Napoleon

    Directory of Open Access Journals (Sweden)

    Gevaert Bert

    2016-04-01

    Full Text Available Though Napoleonic warfare is usually associated with guns and cannons, edged weapons still played an important role on the battlefield. Swords and sabers could dominate battles and this was certainly the case in the hands of experienced cavalrymen. In contrast to gunshot wounds, wounds caused by the saber could be treated quite easily and caused fewer casualties. In 18th and 19th century France, not only manuals about the use of foil and epee were published, but also some important works on the military saber: de Saint Martin, Alexandre Muller… The saber was not only used in individual fights against the enemy, but also as a duelling weapon in the French army.

  6. (Sem saber e (com poder nos estudos organizacionais

    Directory of Open Access Journals (Sweden)

    José Henrique de Faria

    Full Text Available Bacon afirma que saber é poder. Tragtenberg contesta. Essa discussão, na contemporaneidade, faz-se mais importante do que se possa imaginar. Por isso, o objetivo central deste artigo é verificar as relações entre saber e poder, na atualidade, levando em consideração o papel da ciência e dos elementos imediatos a ela relacionados. Quanto aos objetivos específicos deste estudo, destacam-se: · compreender o sentido da filosofia e da ciência e suas relações com a ideologia; · verificar como o discurso da neutralidade axiológica da ciência se apresenta como mito da modernidade e como se dá a presença da "fé" na filosofia e na ciência, na contemporaneidade; · refletir sobre a consolidação da ciência como força produtiva e/ou como mercadoria no atual sistema econômico; · destacar a importância do complexo industrial militar como financiador de grande parte dos atuais estudos científicos; · entender o processo de racionalização, avaliando a importância do pragmatismo e da burocracia universitária como afirmação da ciência na atualidade. O texto conclui que tanto é possível a existência de saber como poder (Bacon como a de não saber, mas com poder (Tragtenberg para compreendermos a relação entre saber e poder.

  7. SABER: a computational method for identifying active sites for new reactions.

    Science.gov (United States)

    Nosrati, Geoffrey R; Houk, K N

    2012-05-01

    A software suite, SABER (Selection of Active/Binding sites for Enzyme Redesign), has been developed for the analysis of atomic geometries in protein structures, using a geometric hashing algorithm (Barker and Thornton, Bioinformatics 2003;19:1644-1649). SABER is used to explore the Protein Data Bank (PDB) to locate proteins with a specific 3D arrangement of catalytic groups to identify active sites that might be redesigned to catalyze new reactions. As a proof-of-principle test, SABER was used to identify enzymes that have the same catalytic group arrangement present in o-succinyl benzoate synthase (OSBS). Among the highest-scoring scaffolds identified by the SABER search for enzymes with the same catalytic group arrangement as OSBS were L-Ala D/L-Glu epimerase (AEE) and muconate lactonizing enzyme II (MLE), both of which have been redesigned to become effective OSBS catalysts, demonstrated by experiments. Next, we used SABER to search for naturally existing active sites in the PDB with catalytic groups similar to those present in the designed Kemp elimination enzyme KE07. From over 2000 geometric matches to the KE07 active site, SABER identified 23 matches that corresponded to residues from known active sites. The best of these matches, with a 0.28 Å catalytic atom RMSD to KE07, was then redesigned to be compatible with the Kemp elimination using RosettaDesign. We also used SABER to search for potential Kemp eliminases using a theozyme predicted to provide a greater rate acceleration than the active site of KE07, and used Rosetta to create a design based on the proteins identified. Copyright © 2012 The Protein Society.

  8. Wind turbine blockset in Saber. General overview and description of the models

    DEFF Research Database (Denmark)

    Iov, Florin; Timbus, Adrian Vasile; Hansen, Anca Daniela

    This report presents a new developed Saber Toolbox for wind turbine applications. This toolbox has been developed during the research project “Simulation Platform to model, optimize and design wind turbines”. The report provides a quick overview of the Saber and then explains the structure...... of this simulation package, which is different than other tools e.g. Matlab/Simulink. Then the structure of the toolbox is shown as well as the description of the developed models. The main focus here is to underline the special structure of the models, which are a mixture of Saber built-in blocks and new developed...... blocks. Since the developed models are based on Saber built-in blocks, a description of the libraries from Saber is given. Then some simulation results using the developed models are shown. Finally some general conclusions regarding this new developed Toolbox as well as some directions for future work...

  9. Wind Turbine Blockset in Saber. General Overview and Description of the Model

    DEFF Research Database (Denmark)

    Iov, Florin; Timbus, Adrian Vasile; Hansen, A. D.

    This report presents a new developed Saber Toolbox for wind turbine applications. This toolbox has been developed during the research project ?Simulation Platform to model, optimize and design wind turbines?. The report provides a quick overview of the Saber and then explains the structure...... of this simulation package, which is different than other tools e.g. Matlab/Simulink. Then the structure of the toolbox is shown as well as the description of the developed models. The main focus here is to underline the special structure of the models, which are a mixture of Saber built-in blocks and new developed...... blocks. Since the developed models are based on Saber built-in blocks, a description of the libraries from Saber is given. Then some simulation results using the developed models are shown. Finally some general conclusions regarding this new developed Toolbox as well as some directions for future work...

  10. Ant- and Ant-Colony-Inspired ALife Visual Art.

    Science.gov (United States)

    Greenfield, Gary; Machado, Penousal

    2015-01-01

    Ant- and ant-colony-inspired ALife art is characterized by the artistic exploration of the emerging collective behavior of computational agents, developed using ants as a metaphor. We present a chronology that documents the emergence and history of such visual art, contextualize ant- and ant-colony-inspired art within generative art practices, and consider how it relates to other ALife art. We survey many of the algorithms that artists have used in this genre, address some of their aims, and explore the relationships between ant- and ant-colony-inspired art and research on ant and ant colony behavior.

  11. Algab õppus "Saber Strike"

    Index Scriptorium Estoniae

    2014-01-01

    Täna algab Eestis, Lätis ja Leedus Ameerika Ühendriikide Euroopa väekoondise õppus "Saber Strike", mille eesmärk on maaväeüksuste koostöö harjutamine. Õppusest võtab osa üle 2000 kaitseväelase Baltimaadest, USAst, Ühendkuningriigist, Taanist, Norrast, Soomest ja Saksamaalt. Eestist osaleb õppusel ligi 400 kaitseväelast

  12. Familia and Comunidad-Based Saberes: Learning in an Indigenous Heritage Community

    Science.gov (United States)

    Urrieta, Luis, Jr.

    2013-01-01

    This article explores how children and youth learned indigenous heritage "saberes" (knowings) through intent community participation in Nocutzepo, Mexico. The "familia" (family) and "comunidad" (community)-based saberes were valuable for skills acquisition, but most important for learning indigenous forms of…

  13. ANT

    DEFF Research Database (Denmark)

    van der Duim, René; Ren, Carina Bregnholm; Jóhannesson, Gunnar Thór

    2017-01-01

    Ten years ago actor-network theory (ANT) entered this journal. To illustrate how the relational ontology and sensibilities of ANT lend themselves to particular kinds of research, we first interrogate the main controversies as a way to open up and discuss the main premises of ANT. These debates...... concern the status and agency of objects and non-humans, ANT’s denial of the explanatory power of social structures, and the political implications of ANT. Second we present ANT’s relevance for tourism studies and discuss what ANT ‘does’ in practice. After summarizing a decade of relations between ANT...... and tourism, we conclude by tracing three future trajectories of how we have ‘moved away with’ ANT into new areas of discovery....

  14. Ancient DNA: Saber-Toothed Cats Are the Same Beasts After All.

    Science.gov (United States)

    Meachen, Julie A

    2017-11-06

    Ancient DNA from the saber-toothed cat Homotherium reveals that the late Pleistocene species from Europe and North America were the same. Homotherium turns out to be only distantly related to the well-known saber-toothed Smilodon. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Saber o no saber… Derecho e información genética

    Directory of Open Access Journals (Sweden)

    José Ignacio Solar Cayón

    2013-12-01

    Full Text Available El extraordinario desarrollo de las técnicas genéticas, con su formidable capacidad de afectación a la autonomía personal y de invasión de los derechos individuales, está teniendo un impacto profundo en el pensamiento jurídico, obligándonos a revisar algunos de los presupuestos en que se funda nuestra concepción de los derechos fundamentales. Así, el reconocimiento del derecho del individuo a no conocer sus datos genéticos parece desafiar nociones esenciales como las de autonomía y racionalidad del sujeto de derechos, vinculadas en el proyecto ilustrado de emancipación del individuo a la idea de pleno acceso al conocimiento. Sin embargo, la propia idea de “ignorancia” no resulta ajena al discurso de fundamentación de los derechos fundamentales, como prueba el papel esencial que el “velo de la ignorancia” desempeña en la revisión de la tradición liberal efectuada por John Rawls. A partir de la teoría de éste y de John Stuart Mill se indaga en los fundamentos filosóficos del derecho a no saber los datos genéticos y en sus límites, ante la existencia de posibles derechos de terceros a acceder a esa información. Asimismo, se pone de manifiesto el papel que en este nuevo contexto juega el Derecho como instancia administradora del conocimiento y de la ignorancia, ante la amenaza de un determinismo genético que parece poner en cuestión en última instancia la idea misma de libertad individual.

  16. CDC Signos Vitales: El TDAH en niños pequeños: Lo que debe saber(ADHD in Young Children: What You Should Know)

    Centers for Disease Control (CDC) Podcasts

    Este podcast está basado en el informe Signos Vitales de los CDC de mayo del 2016. Para los niños de dos a cinco años con TDAH, se recomienda recetar terapia del comportamiento antes que medicamentos. La terapia enseña a los padres formas de mejorar el comportamiento de su hijo y puede ser tan eficaz como los medicamentos, sin el riesgo de producir efectos secundarios.

  17. An overview of the SABER experiment for the TIMED mission

    Science.gov (United States)

    Mlynczak, Martin G.; Russell, James M., III

    1995-01-01

    The Sounding of the Atmosphere Using Broadband Emission Radiometry (SABER) experiment has been selected for flight on the Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED) mission expected to fly in the latter part of this decade. The primary science goal of SABER is to achieve fundamental and important advances in understanding of the energetics, chemistry, and dynamics, in the atmospheric region extending from 60 km to 180 km altitude, which has not been comprehensively observed on a global basis. This will be accomplished using the space flight proven experiment approach of broad spectral band limb emission radiometry. SABER will scan the horizon in 12 selected bands ranging from 1.27 microns to 17 microns wavelength. The observed vertical horizon emission profiles will be mathematically inverted in ground data processing to provide vertical profiles with 2 km vertical resolution, of temperature, O3, H2O, NO, NO2, CO, and CO2. SABER will also observe key emissions needed for energetics studies at 1.27 microns (O2((sup 1)delta)), 2 microns (OH(v = 7,8,9)) 1.6 microns (OH(v = 3,4,5)), 4.3 microns (CO2(v(sub 3))) 5.3 microns (NO) 9.6 microns (O3), and 15 microns (CO2(v(sub 2))). These measurements will be used to infer atomic hydrogen and atomic oxygen, the latter inferred three different ways using only SABER observations. Measurements will be made both night and day over the latitude range from the southern to northern polar regions.

  18. Kinetic Temperature and Carbon Dioxide from Broadband Infrared Limb Emission Measurements Taken from the TIMED/SABER Instrument

    Science.gov (United States)

    Mertens, Christopher J.; Russell III, James M.; Mlynczak, Martin G.; She, Chiao-Yao; Schmidlin, Francis J.; Goldberg, Richard A.; Lopez-Puertas, Manuel; Wintersteiner, Peter P.; Picard, Richard H.; Winick, Jeremy R.; hide

    2008-01-01

    The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) experiment is one of four instruments on NASA's Thermosphere-Ionosphere-Energetics and Dynamics (TIMED) satellite. SABER measures broadband infrared limb emission and derives vertical profiles of kinetic temperature (Tk) from the lower stratosphere to approximately 120 km, and vertical profiles of carbon dioxide (CO2) volume mixing ratio (vmr) from approximately 70 km to 120 km. In this paper we report on SABER Tk/CO2 data in the mesosphere and lower thermosphere (MLT) region from the version 1.06 dataset. The continuous SABER measurements provide an excellent dataset to understand the evolution and mechanisms responsible for the global two-level structure of the mesopause altitude. SABER MLT Tk comparisons with ground-based sodium lidar and rocket falling sphere Tk measurements are generally in good agreement. However, SABER CO2 data differs significantly from TIME-GCM model simulations. Indirect CO2 validation through SABER-lidar MLT Tk comparisons and SABER-radiation transfer comparisons of nighttime 4.3 micron limb emission suggest the SABER-derived CO2 data is a better representation of the true atmospheric MLT CO2 abundance compared to model simulations of CO2 vmr.

  19. Fundamentos del proceso lector. Motivar la lectura en la educación secundaria

    Directory of Open Access Journals (Sweden)

    Bartolomé Delgado Cerrillo

    2007-01-01

    Full Text Available Ante la alarma social provocada por los bajos resultados de los alumnos en "comprensión lectora" (Informe Pisa, pruebas de evaluación..., así como por el interés decreciente por la lectura en el paso de la infancia a la adolescencia, se hace necesario reflexionar sobre los fundamentos del proceso lector, al objeto de diseñar unas actividades de motivación y animación a la lectura en educación secundaria. Nuestra propuesta se incardina en el aula, ya que partimos de la necesidad de relacionar los libros con la consecución real de información, placer y entretenimiento. El estudiante debe saber para qué, cómo, acerca de qué, cuándo, dónde¿ leer de manera provechosa y grata.

  20. CT saber-sheath trachea. Correlation with clinical, chest radiographic and functional findings

    International Nuclear Information System (INIS)

    Trigaux, J.P.; Hermes, G.; Dubois, P.; Beers, B. van; Delaunois, L.; Jamart, J.

    1994-01-01

    The diagnosis of saber-sheath trachea is easy at CT due to its cross-sectional imaging, but the significance of this CT sign has not been evaluated in the diagnosis of chronic obstructive pulmonary disease (COPD). Various signs of COPD were compared between a series of 20 patients with a saber-sheath trachea at CT (tracheal index ≤66%) and a group of 20 pneumologic control patients without saber-sheath trachea (tracheal index ≥70%). These signs include clinical and standard radiographic indices of COPD, sternum-spine distance and 3 functional tests of COPD: forced expiratory volume in one second, carbon monoxide diffusing lung capacity, and funtional residual capacity (FRC). A significant difference was found between the 2 groups, concerning the values of FRC and of sternum-spine distance (p -2 ). The tracheal index was significantly correlated with the FRC values and with the sternum-spine distance. No other significant difference was observed. It is concluded that saber-sheath trachea is basically a sign of hyperinflation. (orig./MG)

  1. CDC Signos Vitales: El TDAH en niños pequeños: Lo que debe saber (ADHD in Young Children: What You Should Know)

    Centers for Disease Control (CDC) Podcasts

    2016-05-03

    Este podcast está basado en el informe Signos Vitales de los CDC de mayo del 2016. Para los niños de dos a cinco años con TDAH, se recomienda recetar terapia del comportamiento antes que medicamentos. La terapia enseña a los padres formas de mejorar el comportamiento de su hijo y puede ser tan eficaz como los medicamentos, sin el riesgo de producir efectos secundarios.  Created: 5/3/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 5/3/2016.

  2. Saber lo que sabe el otro, saber qué sabe el otro: nota sobre la estructura del tiempo lógico en Lacan y en el acontecimiento didáctico/To know that the other knows, to know what the other knows: note on the structure of the logical time in Lacan and the didactic event

    Directory of Open Access Journals (Sweden)

    Mauricio Golfarini

    2007-01-01

    Full Text Available La Teoría del Acontecimiento Didáctico (TAcDi toma elementos de la transposición didáctica de Chevallard, específicamente su noción de cronogénesis, y los reinterpreta a partir de la concepción de temporalidad del psicoanálisis lacaniano. De tal manera, la naturaleza compleja del tiempo lógico permite encontrar aspectos poco explorados en el despliegue temporal del fenómeno didáctico, como el papel de las escansiones o mociones suspendidas. En el presente trabajo se revisa algunos aspectos importantes del tiempo lógico en la TAcDi, a la vez que se plantea un modo adicional de concebir los estadios escansivos en su relación con el saber (supuesto saber del enseñante y el no-saber del enseñado dentro de la ficción didáctica. The Theory of Didactic Event takes elements from the didactic transposition of Chevallard, specifically its notion of chronogenesis, and re-interprets it from the conception of temporality of the lacanian psychoanalysis. In such way, the complex nature of the logical time allows to find unexplored aspects in the temporary unfolding of the didactic phenomenon like the role of the scansions or suspended motions. The present work reviews some important aspects of the logical time in the Theory of the Didactic Event, and simultaneously considers an additional way to conceive the scansive stages in their relation with the knowledge of the teacher and non-knowledge of the taught one within the didactic fiction.

  3. The State of the Thermosphere in 2017 as Observed by SABER

    Science.gov (United States)

    Hunt, L. A.; Mlynczak, M. G.; Marshall, B. T.; Russell, J. M., III

    2017-12-01

    Infrared radiative cooling of the thermosphere by carbon dioxide (CO2, 15 μm) and by nitric oxide (NO, 5.3 μm) has been observed for nearly 16 years by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on the NASA Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED) satellite. SABER has documented dramatic variability in the radiative cooling on timescales ranging from days to the nominal 11-year solar cycle, providing important information about the radiation budget in the upper atmosphere. The effects of Solar Cycle 24 are clearly evident in the infrared radiative cooling of the thermosphere as observed by SABER. The peak NO cooling in SC24 is about one-third less than the maximum seen in SC23 since the beginning of the SABER record in January 2002, while the SC24 CO2 peak is nearly 95% of that in SC23. SC24 has been weakening throughout all of 2017 as measured by the F10.7 index and the sunspot number. Despite this, the radiative cooling by NO and CO2 has not yet reached the low levels of the prior minimum in 2008-2009. This is due to continuing elevated levels of geomagnetic activity as clearly shown by the Ap index. During the years preceding the prior solar minimum, harmonics of the solar rotation period were evident in time series of the NO and CO2 power, and were associated with high speed solar wind streams emanating from coronal holes roughly evenly spaced in solar longitude. Despite a number of large, Earth-facing coronal holes in 2017, periodic features have not yet been observed in spectral/Fourier analysis of the SABER radiative cooling time series. Additional comparisons between solar cycles and with other solar and geomagnetic indicators will also be shown.

  4. Domínio e passividade na economia psíquica de agressores sexuais

    Directory of Open Access Journals (Sweden)

    André Luiz Alexandre do Vale

    2017-01-01

    Full Text Available Este artículo, basado en el saber del Psicoanálisis, se dedica al estudio de los meca - nismos de defensa en juego en los actos de violencia sexual. Nosotros los considera - mos como una de las respuestas posibles del ego ante una excitación desorganiza - dora en el mundo interior. Para elaborar esta hipótesis, vamos a explorar la noción de dominio en la que identificamos dos dimensiones: dominar el objeto externo a través del poder, de la fuerza y, subyacente a esta, la dominación, en el mundo interno, de la invasión de una fuerza pulsional excesiva. En la relación de dominio que se traba en los actos de violencia sexual, el objeto debe ser ultrajado, colocado en la posición de cosa a manipular. Estos actos, de naturaleza eminentemente perversa, apuntan la afirmación de omnipotencia narcisista del sujeto, como un intento extremo de su ego para impedir una experiencia de pasividad vivida ante una alteridad interna inasimi- lable, en busca de salvaguardia psíquica.

  5. Saberes da ayahuasca e processos educativos na religião do Santo Daime

    Directory of Open Access Journals (Sweden)

    Maria Betânia B. Albuquerque

    2012-01-01

    contextos culturales, como en la religión brasileña conocida como Santo Daime. Supongo, por lo que se afirma en los propios himnos de la doctrina, que el Daime (ayahuasca es un profesor y que en la religión se experimenta un proceso educativo donde un conjunto de saberes es distribuido y aprehendido. Metodológicamente, resulta de una búsqueda bibliográfica, documental y de campo. Tiene como fuentes la bibliografía sobre religiones ayahuasqueras, los libros de himnos del Santo Daime y la realización de entrevistas con participantes (daimistas de Brasil y otros países. Teóricamente se inspira en los estudios de Carlos Rodrigues Brandão acerca de la educación como cultura y los escritos de Boaventura de Sousa Santos, restringiendo este texto a la noción de saberes ecológicos y ambientales del autor. Entre los principales saberes del daime resalto: los saberes ecológicos y ambientales, cognitivos, estéticos, medicinales y para la paz.

  6. Presentations from the Workshop On SABER: South Arc Beam Experimental Region, March 15-16, 2006, Menlo Park, California

    International Nuclear Information System (INIS)

    Noble, R.

    2006-01-01

    SABER (the South Arc Beam Experimental Region) is a proposed facility for experiments with 30 GeV electron and positron beams from the SLAC linac. The combination of a short bunch length (s z ∼ 30 microns), high beam charge (3 nC), and small focal spot size (s r = 10 microns) will offer unique scientific opportunities. For more detailed information about the SABER facility and an overview of some of the science possible take a look at the SABER proposal. Initial experiments with electrons could start as early as 2007. A central goal of SABER is to provide a facility responsive to the research needs of its users. The workshop's purposes are to introduce SABER to the potential user community and to explore the range of experiments that are possible. This is an opportunity for the research community to provide input about science at SABER and on the required beam parameters and infrastructure

  7. Unexpected East-West effect in mesopause region SABER temperatures over El Leoncito

    Science.gov (United States)

    Reisin, Esteban R.; Scheer, Jürgen

    2017-05-01

    We find that mesopause region temperatures determined by the SABER instrument on the TIMED satellite during nocturnal overpasses at El Leoncito (31.8°S, 69.3°W) are several kelvins higher when SABER observes from the East than when it observes from the West. We distinguish between altitudes corresponding to the nominal emission heights of the OH and O2 airglow layers. The East-West temperature differences of 4.5 K obtained for OH-equivalent height, and of 3.5 K for O2-equivalent height are surprising, because an effect of the South Atlantic Anomaly on SABER temperature is unexpected. However, the ground-based data obtained with our airglow spectrometer at El Leoncito show that such a SABER artifact can be ruled out. Rather, the phenomenon is explained as a consequence of the temporal sampling of the nocturnal variation, which is mostly due to the semidiurnal tide. The monthly mean tide is strongest from April to September with a mean amplitude of 6.9 K for OH, and of 10.5 K for O2 rotational temperature, but the contribution to the East-West effect varies strongly from month to month because of differences in the temporal sampling. This mechanism should be active at other sites, as well.

  8. Saberes da ayahuasca e processos educativos na religião do Santo Daime

    Directory of Open Access Journals (Sweden)

    Maria Betânia B. Albuquerque

    2012-05-01

    Full Text Available Este estudo volta-se para os saberes da ayahuasca, beberagem de origem indígenafeita da combinação de um cipó e as folhas de um arbusto da Amazônia, utilizada em diferentescontextos culturais como é o caso da religião brasileira conhecida como Santo Daime. Parto dopressuposto, afirmado nos próprios hinos da doutrina, de que o daime (ayahuasca é um professore que na religião vivencia-se um processo educativo no qual um conjunto de saberes é circulado eapreendido. Metodologicamente, resulta de uma pesquisa bibliográfica, documental e de campo.Têm como fontes a bibliografia sobre as religiões ayahuasqueiras, os cadernos de hinos do SantoDaime e a realização de entrevistas com daimistas do Brasil e outros países. Teoricamente, inspirasenos estudos de Carlos Rodrigues Brandão acerca da educação como cultura e nos escritos deBoaventura de Sousa Santos, restringindo este texto à noção de “ecologia de saberes” deste autor.Dentre os principais saberes do daime destaco: saberes ecológicos-ambientais, cognitivos, estéticos,medicinais, e para a paz.

  9. Ant-plant mutualism: a dietary by-product of a tropical ant's macronutrient requirements.

    Science.gov (United States)

    Arcila Hernández, Lina M; Sanders, Jon G; Miller, Gabriel A; Ravenscraft, Alison; Frederickson, Megan E

    2017-12-01

    Many arboreal ants depend on myrmecophytic plants for both food and shelter; in return, these ants defend their host plants against herbivores, which are often insects. Ant-plant and other mutualisms do not necessarily involve the exchange of costly rewards or services; they may instead result from by-product benefits, or positive outcomes that do not entail a cost for one or both partners. Here, we examined whether the plant-ant Allomerus octoarticulatus pays a short-term cost to defend their host plants against herbivores, or whether plant defense is a by-product benefit of ant foraging for insect prey. Because the food offered by ant-plants is usually nitrogen-poor, arboreal ants may balance their diets by consuming insect prey or associating with microbial symbionts to acquire nitrogen, potentially shifting the costs and benefits of plant defense for the ant partner. To determine the effect of ant diet on an ant-plant mutualism, we compared the behavior, morphology, fitness, stable isotope signatures, and gaster microbiomes of A. octoarticulatus ants nesting in Cordia nodosa trees maintained for nearly a year with or without insect herbivores. At the end of the experiment, ants from herbivore exclosures preferred protein-rich baits more than ants in the control (i.e., herbivores present) treatment. Furthermore, workers in the control treatment were heavier than in the herbivore-exclusion treatment, and worker mass predicted reproductive output, suggesting that foraging for insect prey directly increased ant colony fitness. The gaster microbiome of ants was not significantly affected by the herbivore exclusion treatment. We conclude that the defensive behavior of some phytoecious ants is a by-product of their need for external protein sources; thus, the consumption of insect herbivores by ants benefits both the ant colony and the host plant. © 2017 by the Ecological Society of America.

  10. Ant Larval Demand Reduces Aphid Colony Growth Rates in an Ant-Aphid Interaction

    Directory of Open Access Journals (Sweden)

    James M. Cook

    2012-02-01

    Full Text Available Ants often form mutualistic interactions with aphids, soliciting honeydew in return for protective services. Under certain circumstances, however, ants will prey upon aphids. In addition, in the presence of ants aphids may increase the quantity or quality of honeydew produced, which is costly. Through these mechanisms, ant attendance can reduce aphid colony growth rates. However, it is unknown whether demand from within the ant colony can affect the ant-aphid interaction. In a factorial experiment, we tested whether the presence of larvae in Lasius niger ant colonies affected the growth rate of Aphis fabae colonies. Other explanatory variables tested were the origin of ant colonies (two separate colonies were used and previous diet (sugar only or sugar and protein. We found that the presence of larvae in the ant colony significantly reduced the growth rate of aphid colonies. Previous diet and colony origin did not affect aphid colony growth rates. Our results suggest that ant colonies balance the flow of two separate resources from aphid colonies- renewable sugars or a protein-rich meal, depending on demand from ant larvae within the nest. Aphid payoffs from the ant-aphid interaction may change on a seasonal basis, as the demand from larvae within the ant colony waxes and wanes.

  11. Comparison of rotational temperature derived from ground-based OH airglow observations with TIMED/SABER to evaluate the Einstein Coefficients

    Science.gov (United States)

    Liu, W.; Xu, J.; Smith, A. K.; Yuan, W.

    2017-12-01

    Ground-based observations of the OH(9-4, 8-3, 6-2, 5-1, 3-0) band airglows over Xinglong, China (40°24'N, 117°35'E) from December 2011 to 2014 are used to calculate rotational temperatures. The temperatures are calculated using five commonly used Einstein coefficient datasets. The kinetic temperature from TIMED/SABER is completely independent of the OH rotational temperature. SABER temperatures are weighted vertically by weighting functions calculated for each emitting vibrational state from two SABER OH volume emission rate profiles. By comparing the ground-based OH rotational temperature with SABER's, five Einstein coefficient datasets are evaluated. The results show that temporal variations of the rotational temperatures are well correlated with SABER's; the linear correlation coefficients are higher than 0.72, but the slopes of the fit between the SABER and rotational temperatures are not equal to 1. The rotational temperatures calculated using each set of Einstein coefficients produce a different bias with respect to SABER; these are evaluated over each of vibrational levels to assess the best match. It is concluded that rotational temperatures determined using any of the available Einstein coefficient datasets have systematic errors. However, of the five sets of coefficients, the rotational temperature derived with the Langhoff et al.'s (1986) set is most consistent with SABER. In order to get a set of optimal Einstein coefficients for rotational temperature derivation, we derive the relative values from ground-based OH spectra and SABER temperatures statistically using three year data. The use of a standard set of Einstein coefficients will be beneficial for comparing rotational temperatures observed at different sites.

  12. CURRÍCULO E RESISTÊNCIA: horizontes para uma ecologia de saberes

    Directory of Open Access Journals (Sweden)

    Ana Elisa de Castro Freitas

    2016-09-01

    Full Text Available O presente artigo registra uma proposta curricular inovadora, desenvolvida no Setor Litoral da Universidade Federal do Paraná. Ancorada em um projeto político-pedagógico que busca superar concepções dominantes no âmbito das políticas curriculares, esta proposta investe na redefinição dos espaços pedagógicos, potencializando fluxos de saberes, poderes e identidades. Organizado em três fases/tempos articulados a três eixos/espaços, o desenho curricular assume uma forma tridimensional e modular. Seus espaços potencializam a cultura do trabalho coletivo e integrado em práticas inter e multidisciplinares, oportunizando movimentos de resistência à racionalidade instrumental do currículo normativo-prescritivo, dominante nas instituições de ensino superior brasileiras. Para além das competências profissionais, a formação é plena de potência humanizadora e emancipatória, alinhando-se com a proposta de uma ecologia de saberes. As relações de produção e circulação de saberes são socializadas. Neste sentido, o currículo tridimensional representa uma importante ruptura com a racionalidade formalmente unidimensional, linear e progressiva, inspiradora da formação universitária ocidental, que fragmenta e distancia os campos de saberes científicos, alienando os sujeitos dos processos e meios de produção, aquisição e circulação de conhecimentos.

  13. Saberes agrícolas tradicionales como programa académico

    Directory of Open Access Journals (Sweden)

    J. Antonio Gómez Espinoza

    2008-01-01

    Full Text Available En el marco de las crisis social y ambiental del tercer milenio, se hace necesario repensar la universidad, sus paradigmas, el concepto de educación y su modelo educativo para impactar en la construcción de la nueva sociedad. Los Saberes Agrícolas Tradicionales (SAT aportan elementos conceptuales básicos para la implementación y desarrollo de una sociedad sustentable. A partir del rescate, la sistematización de los SAT y el diálogo intercultural SAT-ciencia, se propone incorporar los Saberes Agrícolas Tradicionales como programa académico en las Instituciones de Enseñanza y Aprendizaje Agrícola del nivel Superior (IEAS.

  14. Responsabilidad de los contadores públicos ante ilícitos tributarios en empresas comerciales del sector ferretero del Municipio Alberto Adriani del estado Mérida

    OpenAIRE

    Almeida, Jhoner; Cote, Marilys; Briceño, María Eugenia; Rojas, Ma. Elizabeth

    2011-01-01

    La actuación del contador público está cubierta de responsabilidad y compromiso y ante esto debe actuar con rectitud y buena fe, mantener el honor, dignidad y capacidad profesional. No obstante, hay situaciones en la que los contadores incurren en actos contrarios a la norma legal, lo cual puede provocar daños a terceros o al Estado. Tal es el caso de los ilícitos tributarios que constituyen toda acción u omisión violatoria de las normas tributarias previstas en el Código Orgánico...

  15. Chapter 3: Design of the Saber-Tooth Project.

    Science.gov (United States)

    Ward, Phillip

    1999-01-01

    Used data from interviews, surveys, and document analysis to describe the methods and reform processes of the Saber Tooth Project, examining selection of sites; demographics (school sites, teachers, data sources, and project assumptions); and project phases (development, planning, implementation, and support). The project's method of reform was…

  16. Saber-sheath trachea as a marker of severe airflow obstruction in chronic obstructive pulmonary disease.

    Science.gov (United States)

    Ciccarese, Federica; Poerio, Antonio; Stagni, Silvia; Attinà, Domenico; Fasano, Luca; Carbonara, Paolo; Bacchi Reggiani, Maria Letizia; Zompatori, Maurizio

    2014-02-01

    Saber-sheath trachea is a specific radiographic parameter for chronic obstructive pulmonary disease (COPD), which consists of marked coronal narrowing associated with sagittal widening (tracheal index saber-sheath trachea and clinical-radiological findings in a group of patients with COPD of varying severity. We evaluated the chest radiographs of 71 patients with COPD distributed as follows: GOLD class I, 8/71 (11.3 %); class II, 34/71 (47.9 %); class III, 16/71(22.5 %); class IV, 13/71 (18.3 %). In 52/71 (73.2 %) patients we also evaluated chest computed tomography (CT) scans. We analyzed the prevalence of saber-sheath trachea and its correlation with the Tiffenau index, GOLD stage and radiological signs of COPD. Moreover, we evaluated the sensitivity, specificity and accuracy of chest radiography as compared to CT taken as the gold standard, and the correlation between the radiographic and CT tracheal index. Saber-sheath trachea was found in 18/71 (25.4 %) patients, with a greater prevalence in patients with lower Tiffenau Index (p = 0.02), GOLD stages III-IV and visual severity score 3 (severe) on chest CT. Saber-sheath trachea was not found to be related to other radiological signs of COPD. The sensitivity, specificity and accuracy values of radiography were 72.2, 97.0 and 88.5 %, with perfect concordance between the radiographic and CT tracheal index (p Saber-sheath trachea is linked to the functional severity of airway obstruction, but not to other radiological signs of COPD. Thus, evaluation of the trachea at chest radiography is strongly recommended.

  17. Fire Ant Bites

    Science.gov (United States)

    ... Favorite Name: Category: Share: Yes No, Keep Private Fire Ant Bites Share | Fire ants are aggressive, venomous insects that have pinching ... across the United States, even into Puerto Rico. Fire ant stings usually occur on the feet or ...

  18. Aziz Nacib Ab’Saber, geógrafo brasileiro

    Directory of Open Access Journals (Sweden)

    Neli Aparecida de Mello-Théry

    2012-03-01

    Full Text Available Na ocasião do falecimento de Aziz Nacib Ab’Saber faz-se uma retrospectiva da sua carreira científica. Ela foi marcada por significativa produção científica no campo da Geografia Fisica, particularmente os estudos da paisagem e da geomorfologia. No campo da conservação da Natureza Aziz foi um pioneiro, e tornou-se um îcone dos movimentos ambientais, pela qualidade das análises e pela firmeza na defesa das posições que julgava justas.A l’occasion de la mort d’Aziz Nacib Ab’Saber le texte fait une rétrospective de sa carrière scientifique. Elle a été marquée par une importante production scientifique dans le domaine de la géographie physique, en particulier les études de paysage et la géomorphologie. Dans le domaine de la conservation de la nature Aziz a été un pionnier, et est devenu une icône du mouvement environnemental, par la qualité de ses analyses et par sa fermeté dans la défense des positions qu’il pensait justes.On the occasion of the death of Aziz Nacib Ab’Saber the text makes a retrospective of his scientific career, marked by significant scientific production in the fields of physical geography, particularly studies of landscape and geomorphology. In the field of nature conservation Aziz was a pioneer, and became an icon of the environmental movement, by the quality of its analysis and by the firmness in the defense of positions he thought justs.

  19. Induced resistance to septorial leaf blotch disease in wheat cv. 'SaberBeg' and its hybrids by fast neutrons

    International Nuclear Information System (INIS)

    Ibrahim, I.; Al-Marooff, E.; AI-Janabi, A.; Mahmood, A.; AI-Aubaidi

    1990-01-01

    Full text: Seeds of 'SaberBeg' and its hybrids in F 2 generation were irradiated with different doses of fast neutrons. 1324 variants selected from M 2 and F 4 M 2 were evaluated for resistance to septorial leaf blotch (Septoria tritici Rob ex Desm) with artificial inoculation under field conditions, through 3 successive generations. Results revealed 55 variants moderately resistant, along with better agronomic traits such as stiff stem, earliness in maturity and good adaption to semiarid zone conditions. The highest number of such variants was obtained from irradiated 'SaberBeg' x 'Mexipak' and 'SaberBeg' x ('Mexipak' x 'AbuGhraib 4'), while the lowest number was found from 'SaberBeg' x 'Araz'. (author)

  20. "Artículo 67: educación es un derecho de la persona y un servicio público con una función social". Saberes técnicos y saberes políticos sobre la Educación en Colombia. 1978 - 1994

    OpenAIRE

    Heredia Duarte, María Isabel

    2012-01-01

    "Artículo 67: La educación es... un derecho de la persona y un servicio público con una función social Saberes técnicos y saberes políticos sobre la Educación en Colombia 1978 - 1994" es un trabajo de investigación que tiene como propósito: analizar desde la perspectiva histórica, los juegos de relaciones de saber-poder que entablaron los saberes políticos y técnicos, presentes en las expresiones escritas en las revistas sobre Educación en Colombia en el período comprendido entre 1978 a 1994....

  1. EDUCAÇÃO INFANTIL, CURRÍCULO E SABERES DOCENTES: PERCURSOS DE UMA PESQUISA-AÇÃO

    Directory of Open Access Journals (Sweden)

    Elaine Luciana Silva Sobral

    2011-03-01

    Full Text Available Apresentamos os processos, percursos e achados de uma pesquisa-ação que teve como objetivos: investigar saberes docentes necessários ao desenvolvimento de uma proposta curricular numa instituição pública de educação infantil e contribuir para a (re significação, por parte de professores, de saberes necessários à construção de uma proposta curricular para a educação infantil. Com a participação de 19 sujeitos desenvolvemos observações não-participantes; entrevistas semi-estruturadas (individuais e coletivas; análise de documentos e seminários de estudos reflexivos. Analisamos duas categorias: 1 Saberes docentes relativos às concepções de currículo/proposta curricular e 2 Saberes docentes relativos às especificidades da educação infantil. Percebemos avanços no que se refere à (resignificação de tais saberes por parte dos sujeitos, configurando rupturas importantes com suas concepções iniciais. Apontamos para a necessidade de um trabalho de formação permanente, no contexto da instituição, de modo a propiciar o diálogo entre as práticas pedagógicas e as propostas curriculares.

  2. Un acercamiento al desarrollo del saber de Estado Apuntes para una agenda de investigación

    Directory of Open Access Journals (Sweden)

    Edwin Cruz Rodríguez

    2007-01-01

    Full Text Available Este artículo se propone realizar una aproximación al desarrollo del saber de Estado, entendido como el conjunto de conocimientos necesarios para dirigir el Estado, planteando algunos elementos que pueden ahondarse en la investigación de este campo en Colombia y Latinoamérica. Es posible acercarse al tipo específico de saber que permite al Estado ejercer su poder desde dos perspectivas: una histórica, que caracteriza la formación de este saber en relación con la del Estado nación y con los contextos sociales cambiantes que supone el advenimiento de la modernidad; y otra teórica, que permite aproximarse a las relaciones causales que explican el desarrollo del saber de Estado entre las instituciones políticas, los contextos sociales y los acontecimientos históricos relevantes, entre otros. El saber de Estado se ha desarrollado por causas que se desprenden de las relaciones entre el desarrollo del conocimiento y su institucionalización, las instituciones estatales y los contextos sociales problemáticos. La causalidad entre estos no es lineal y varía de acuerdo con las relaciones de poder en contextos nacionales específicos.

  3. Ant aggression and evolutionary stability in plant-ant and plant-pollinator mutualistic interactions.

    Science.gov (United States)

    Oña, L; Lachmann, M

    2011-03-01

    Mutualistic partners derive a benefit from their interaction, but this benefit can come at a cost. This is the case for plant-ant and plant-pollinator mutualistic associations. In exchange for protection from herbivores provided by the resident ants, plants supply various kinds of resources or nests to the ants. Most ant-myrmecophyte mutualisms are horizontally transmitted, and therefore, partners share an interest in growth but not in reproduction. This lack of alignment in fitness interests between plants and ants drives a conflict between them: ants can attack pollinators that cross-fertilize the host plants. Using a mathematical model, we define a threshold in ant aggressiveness determining pollinator survival or elimination on the host plant. In our model we observed that, all else being equal, facultative interactions result in pollinator extinction for lower levels of ant aggressiveness than obligatory interactions. We propose that the capacity to discriminate pollinators from herbivores should not often evolve in ants, and when it does it will be when the plants exhibit limited dispersal in an environment that is not seed saturated so that each seed produced can effectively generate a new offspring or if ants acquire an extra benefit from pollination (e.g. if ants eat fruit). We suggest specific mutualism examples where these hypotheses can be tested empirically. © 2010 The Authors. Journal of Evolutionary Biology © 2010 European Society For Evolutionary Biology.

  4. Mesospheric Water Vapor Retrieved from SABER/TIMED Measurements

    Science.gov (United States)

    Feofilov, Arte, G.; Yankovsky, Valentine A.; Marshall, Benjamin T.; Russell, J. M., III; Pesnell, W. D.; Kutepov, Alexander A.; Goldberg, Richard A.; Gordley, Larry L.; Petelina, Svetlama; Mauilova, Rada O.; hide

    2007-01-01

    The SABER instrument on board the TIMED satellite is a limb scanning infrared radiometer designed to measure temperature and minor constituent vertical profiles and energetics parameters in the mesosphere and lower thermosphere (MLT) The H2O concentrations are retrieved from 6.3 micron band radiances. The interpretation of this radiance requires developing a non-LTE H2O model that includes energy exchange processes with the system of O3 and O2 vibrational levels populated at the daytime through a number of photoabsorption and photodissociation processes. We developed a research model base on an extended H2O non-LTE model of Manuilova coupled with the novel model of the electronic kinetics of the O2 and O3 photolysis products suggested by Yankosvky and Manuilova. The performed study of this model helped u to develop and test an optimized operational model for interpretation of SABER 6.3 micron band radiances. The sensitivity of retrievals to the parameters of the model is discussed. The H2O retrievals are compared to other measurements for different seasons and locations.

  5. AntStar: Enhancing Optimization Problems by Integrating an Ant System and A⁎ Algorithm

    Directory of Open Access Journals (Sweden)

    Mohammed Faisal

    2016-01-01

    Full Text Available Recently, nature-inspired techniques have become valuable to many intelligent systems in different fields of technology and science. Among these techniques, Ant Systems (AS have become a valuable technique for intelligent systems in different fields. AS is a computational system inspired by the foraging behavior of ants and intended to solve practical optimization problems. In this paper, we introduce the AntStar algorithm, which is swarm intelligence based. AntStar enhances the optimization and performance of an AS by integrating the AS and A⁎ algorithm. Applying the AntStar algorithm to the single-source shortest-path problem has been done to ensure the efficiency of the proposed AntStar algorithm. The experimental result of the proposed algorithm illustrated the robustness and accuracy of the AntStar algorithm.

  6. Runtime analysis of the 1-ANT ant colony optimizer

    DEFF Research Database (Denmark)

    Doerr, Benjamin; Neumann, Frank; Sudholt, Dirk

    2011-01-01

    The runtime analysis of randomized search heuristics is a growing field where, in the last two decades, many rigorous results have been obtained. First runtime analyses of ant colony optimization (ACO) have been conducted only recently. In these studies simple ACO algorithms such as the 1-ANT...... that give us a more detailed impression of the 1-ANT’s performance. Furthermore, the experiments also deal with the question whether using many ant solutions in one iteration can decrease the total runtime....

  7. Microorganisms transported by ants induce changes in floral nectar composition of an ant-pollinated plant.

    Science.gov (United States)

    de Vega, Clara; Herrera, Carlos M

    2013-04-01

    Interactions between plants and ants abound in nature and have significant consequences for ecosystem functioning. Recently, it has been suggested that nectar-foraging ants transport microorganisms to flowers; more specifically, they transport yeasts, which can potentially consume sugars and alter nectar composition. Therefore, ants could indirectly change nectar sugar profile, an important floral feature involved in the plant-pollinator mutualism. But this novel role for ants has never been tested. We here investigate the effects of nectarivorous ants and their associated yeasts on the floral nectar sugar composition of an ant-pollinated plant. Differences in the nectar sugar composition of ant-excluded and ant-visited flowers were examined in 278 samples by using high-performance liquid-chromatography. The importance of the genetic identity and density of ant-transported basidiomycetous and ascomycetous yeasts on the variation of nectar traits was also evaluated. Ant visitation had significant effects on nectar sugar composition. The nectar of ant-visited flowers contained significantly more fructose, more glucose, and less sucrose than the nectar of ant-excluded flowers, but these effects were context dependent. Nectar changes were correlated with the density of yeast cells in nectar. The magnitude of the effects of ant-transported ascomycetes was much higher than that of basiodiomycetes. Ants and their associated yeasts induce changes in nectar sugar traits, reducing the chemical control of the plant over this important floral trait. The potential relevance of this new role for ants as indirect nectar modifiers is a rich topic for future research into the ecology of ant-flower interactions.

  8. Una lectura teológica de la realidad: ¿A cuáles nuevos saberes recurrir o con qué saberes contar?

    Directory of Open Access Journals (Sweden)

    Geraldo De Mori

    2012-01-01

    Full Text Available Tras un breve recurrido histórico del lugar de los otros saberes en la teología práctica/pastoral, el presente artículo hace un análisis de cómo estos saberes se encuentran hoy día en los principales modelos de teología práctica/pastoral, a saber: 1 las teologías prácticas empíricas, más presentes en los países anglosajones, que dialogan mucho con la sicología y la pedagogía; 2 las teologías prácticas críticas, como son las teologías política y de la liberación, que hacen de la praxis la categoría central del quehacer teológico y entran en un diálogo estrecho sobre todo con la sociología, la economía y las ciencias políticas; 3 las teologías prácticas/pastorales fundamentales, propuesta por Browning, que intentan dialogar sobre todo con la filosofía hermenéutica. En un tercer momento, partiendo de tres categorías de la ética de Paul Ricoeur, es decir, la estima de sí, el cuidado el otro y la búsqueda de instituciones justas, el texto propone pensar el quehacer de la teología práctica/ pastoral alrededor de esas categorías, mostrando a qué saberes recurrir.After a brief historical review of the role of other knowledges in practical/pastoral theology, this article analyzes how these knowledges are found today in the main models of practical/pastoral theology, namely: 1 empirical practical theologies, more present in Anglo-Saxon countries, which are often in dialogue with psychology and pedagogy; 2 critical practical theologies, such as political and liberation theologies, which make praxis the central category of the theological task and that are in close dialogue mainly with sociology, economics and political science; 3 fundamental practical/pastoral theologies, proposed by Browning, which attempt to dialogue principally with hermeneutic philosophy. In a third stage, based on Paul Ricoeur's three ethical categories, that is to say, self-esteem, caring for others and the pursuit of just institutions, the

  9. New formulations of bupivacaine for the treatment of postoperative pain: liposomal bupivacaine and SABER-Bupivacaine.

    Science.gov (United States)

    Skolnik, Aaron; Gan, Tong J

    2014-08-01

    Although generally considered both safe and effective, local anesthetics are often used in conjunction with opioids postoperatively in part because of the limited duration of drug action of local anesthetics. Much interest exists in extending the duration of local anesthetics' effects, which may reduce the requirement for opioid pain medications that are frequently associated with side effects, including nausea and vomiting, pruritus and respiratory depression. This article introduces liposomal bupivacaine and SABER®-Bupivacaine, two new formulations of bupivacaine that increase the duration of analgesia postoperatively through two novel slow-release technologies. The pharmacodynamics, pharmacokinetics, efficacy and safety of both preparations of bupivacaine are reviewed. An electronic database search conducted using the Cochrane Central Register of Controlled Trials and MEDLINE/PubMed with the following search terms: 'bupivacaine,' 'liposomal bupivacaine', 'liposome bupivacaine', 'Exparel', 'SABER-Bupivacaine', 'SABER Bupivacaine', and 'SABER' yielded 90 articles (no language or date of publication restrictions were imposed). Clinical trials involving liposomal bupivacaine and SABER-Bupivacaine indicate that both safely prolong analgesia, while decreasing opioid requirements when compared with placebo. However, additional clinical studies are necessary to better determine the efficacy and cost-effectiveness of these long-acting local anesthetic formulations.

  10. Chapter 1: An Introduction to the Saber-Tooth Project.

    Science.gov (United States)

    Ward, Phillip

    1999-01-01

    Introduces a theme issue on the Saber-Tooth Project, an ongoing reform effort involving a university and school district that collaborate to improve middle school physical education by improving teaching conditions and engaging teachers in professional development emphasizing curriculum improvement. The monograph explains the nature of…

  11. Mesospheric H2O Concentrations Retrieved from SABER/TIMED Measurements

    Science.gov (United States)

    Feofilov, A. G.; Marshall, B. T.; Garcia-Comas, M.; Kutepov, A. A.; Lopez-Puertas, M.; Manuilova, R. O.; Yankovsky, V.A.; Goldberg, R. A.; Gordley, L. L.; Petelin, S.; hide

    2008-01-01

    The SABER instrument on board the TIMED Satellite is a limb scanning infrared radiometer designed to measure temperature and minor constituent vertical profiles and energetics parameters in the mesosphere and lower thermosphere (MLT). The H2O concentrations are retrieved from 6.3 micron band radiances. The populations of H2O(v2) vibrational levels are in non-Local Thermodynamic Equilibrium (non-LTE) above approximately 55 km altitude and the interpretation of 6.3 micron radiance requires utilizing non-LTE H2O model that includes various energy exchange processes in the system of H2O vibrational levels coupled with O2, N2, and CO2 vibrational levels. We incorporated these processes including kinetics of O2/O3 photolysis products to our research non-LTE H2O model and applied it for the development and optimization of SABER operational model. The latter has been validated using simultaneous SCISAT1/ACE occultation measurements. This helped us to estimate CO2(020)-O2(X,v=I), O2(X,v=I)- H2O(010), and O2(X,v=1) O rates at mesopause temperatures that is critical for an adequate interpretation of non-LTE H2O radiances in the MLT. The first distributions of seasonal and meridional H2O concentrations retrieved from SABER 6.3 micron radiances applying an updated non-LTE H2O model are demonstrated and discussed.

  12. A comparison of ground-based hydroxyl airglow temperatures with SABER/TIMED measurements over 23° N, India

    Science.gov (United States)

    Parihar, Navin; Singh, Dupinder; Gurubaran, Subramanian

    2017-03-01

    Ground-based observations of OH (6, 2) Meinel band nightglow were carried out at Ranchi (23.3° N, 85.3° E), India, during January-March 2011, December 2011-May 2012 and December 2012-March 2013 using an all-sky imaging system. Near the mesopause, OH temperatures were derived from the OH (6, 2) Meinel band intensity information. A limited comparison of OH temperatures (TOH) with SABER/TIMED measurements in 30 cases was performed by defining almost coincident criterion of ±1.5° latitude-longitude and ±3 min of the ground-based observations. Using SABER OH 1.6 and 2.0 µm volume emission rate profiles as the weighing function, two sets of OH-equivalent temperature (T1. 6 and T2. 0 respectively) were estimated from its kinetic temperature profile for comparison with OH nightglow measurements. Overall, fair agreement existed between ground-based and SABER measurements in the majority of events within the limits of experimental errors. Overall, the mean value of OH-derived temperatures and SABER OH-equivalent temperatures were 197.3 ± 4.6, 192.0 ± 10.8 and 192.7 ± 10.3 K, and the ground-based temperatures were 4-5 K warmer than SABER values. A difference of 8 K or more is noted between two measurements when the peak of the OH emission layer lies in the vicinity of large temperature inversions. A comparison of OH temperatures derived using different sets of Einstein transition probabilities and SABER measurements was also performed; however, OH temperatures derived using Langhoff et al. (1986) transition probabilities were found to compare well.

  13. RELIGIÃO E EDUCAÇÃO: OS SABERES DA AYAHUASCA NO SANTO DAIME

    Directory of Open Access Journals (Sweden)

    Maria Betânia Barbosa Albuquerque

    2011-05-01

    Full Text Available O artigo analisa os saberes da ayahuasca, beberagem de origem indígena feita da combinação de um cipó e as folhas de um arbusto da Amazônia, utilizada em diferentes contextos culturais como é o caso da religião brasileira conhecida como Santo Daime. Metodologicamente, o artigo resulta de uma pesquisa bibliográfica, documental e de campo. Tem como fontes a bibliografia sobre as religiões ayahuasqueiras, os cadernos de hinos do Santo Daime e a realização de entrevistas com daimistas do Brasil e outros países. Teoricamente, inspira-se nos estudos de Carlos Rodrigues Brandão acerca da educação como cultura e nos escritos de Boaventura de Sousa Santos, restringindo este texto à noção de “ecologia de saberes” deste autor. Parto do pressuposto de que o daime (ayahuasca é um professor e que na religião vivencia-se um processo educativo no qual um conjunto de saberes é circulado e apreendido. Dentre os principais saberes do

  14. Construcción de saberes en la web social: estado de la cuestión

    Directory of Open Access Journals (Sweden)

    Edgar Villegas Iriarte

    2016-10-01

    Full Text Available Este artículo presenta el estado de la cuestión sobre la construcción de saberes y sentidos en la web social. Es resultado de una investigación doctoral que busca desarrollar un modelo descriptivo y comprensivo de las relaciones, movimientos y actuaciones en torno a la producción de saberes en la Web social. Para hacerlos visibles, se concentró la mirada investigativa a través de los saberes viajeros. Se revisaron metabuscadores académicos y revistas especializadas; se realizó una preselección de artículos y, posteriormente, una selección que permitió revisar en detalle textos procedentes de investigaciones realizadas en Asia (incluidas Australia y Nueva Zelanda, Europa, Latinoamérica y Norteamérica. Se encontró un área de reciente creación con una alta velocidad de cambio. Igualmente, que aún no se logran comprender las lógicas de las motivaciones que llevan a las personas a crear o mantener proyectos basados en la colaboración. Finalmente, los sentidos que se le asignan a los saberes viajeros en la web social corresponden a formas de expresión, identidad y relación (socialidad.

  15. Spectral wave analysis at the mesopause from SCIAMACHY airglow data compared to SABER temperature spectra

    Directory of Open Access Journals (Sweden)

    M. Ern

    2009-01-01

    Full Text Available Space-time spectral analysis of satellite data is an important method to derive a synoptic picture of the atmosphere from measurements sampled asynoptically by satellite instruments. In addition, it serves as a powerful tool to identify and separate different wave modes in the atmospheric data. In our work we present space-time spectral analyses of chemical heating rates derived from Scanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY hydroxyl nightglow emission measurements onboard Envisat for the years 2002–2006 at mesopause heights. Since SCIAMACHY nightglow hydroxyl emission measurements are restricted to the ascending (nighttime part of the satellite orbit, our analysis also includes temperature spectra derived from 15 μm CO2 emissions measured by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER instrument. SABER offers better temporal and spatial coverage (daytime and night-time values of temperature and a more regular sampling grid. Therefore SABER spectra also contain information about higher frequency waves. Comparison of SCIAMACHY and SABER results shows that SCIAMACHY, in spite of its observational restrictions, provides valuable information on most of the wave modes present in the mesopause region. The main differences between wave spectra obtained from these sensors can be attributed to the differences in their sampling patterns.

  16. Harnessing ant defence at fruits reduces bruchid seed predation in a symbiotic ant-plant mutualism.

    Science.gov (United States)

    Pringle, Elizabeth G

    2014-06-22

    In horizontally transmitted mutualisms, mutualists disperse separately and reassemble in each generation with partners genetically unrelated to those in the previous generation. Because of this, there should be no selection on either partner to enhance the other's reproductive output directly. In symbiotic ant-plant mutualisms, myrmecophytic plants host defensive ant colonies, and ants defend the plants from herbivores. Plants and ants disperse separately, and, although ant defence can indirectly increase plant reproduction by reducing folivory, it is unclear whether ants can also directly increase plant reproduction by defending seeds. The neotropical tree Cordia alliodora hosts colonies of Azteca pittieri ants. The trees produce domatia where ants nest at stem nodes and also at the node between the peduncle and the rachides of the infloresence. Unlike the stem domatia, these reproductive domatia senesce after the tree fruits each year. In this study, I show that the tree's resident ant colony moves into these ephemeral reproductive domatia, where they tend honeydew-producing scale insects and patrol the nearby developing fruits. The presence of ants significantly reduced pre-dispersal seed predation by Amblycerus bruchid beetles, thereby directly increasing plant reproductive output.

  17. "Ant-egg" cataract revisited

    DEFF Research Database (Denmark)

    Clemmensen, Kåre; Enghild, Jan J; Ivarsen, Anders

    2017-01-01

    -ray scans and electron microscopy. The purpose of this study was to further characterize "ant-egg" cataract using modern technology and display the history of the "ant-eggs" after cataract extraction. METHODS: "Ant-eggs" were examined using Heidelberg SPECTRALIS Optical Coherence Tomography (OCT...

  18. Evolutionary History of Saber-Toothed Cats Based on Ancient Mitogenomics

    NARCIS (Netherlands)

    Paijmans, Johanna L.A.; Barnett, Ross; Gilbert, M. Thomas P.; Zepeda-Mendoza, M. Lisandra; Reumer, Jelle W.F.; de Vos, John; Zazula, Grant; Nagel, Doris; Baryshnikov, Gennady F.; Leonard, Jennifer A.; Rohland, Nadin; Westbury, Michael V.; Barlow, Axel; Hofreiter, Michael

    2017-01-01

    Saber-toothed cats (Machairodontinae) are among the most widely recognized representatives of the now largely extinct Pleistocene megafauna. However, many aspects of their ecology, evolution, and extinction remain uncertain. Although ancient-DNA studies have led to huge advances in our knowledge of

  19. Entre el poder y el saber: Recuento del pensamiento latinoamericano

    Directory of Open Access Journals (Sweden)

    Luis Ramiro Beltrán Salmón

    2008-12-01

    Full Text Available Refiere el texto un resumen y análisis del libro "Entre el Saber y el Poder: Pensamiento comunicacional Latinoamericano". Libro de notable ejercicio de reflexión, de visión holística y totalizadora que recupera y sistematiza lo que se ha pensado sobre la comunicación y sus correspondientes dilemas en la América hispano-lusitana. La primera parte "la comunicación en las tramas del poder": con dos secciones, la una dedicada a la coyuntura de la Guerra Fría y la segunda dedicada a la coyuntura de la Globalización. La segunda "La comunicación en el umbral del saber" con dos secciones: la primera recoge materiales de la Educación para la comunicación y la otra la investigación de la comunicación.

  20. How ants drop out: ant abundance on tropical mountains.

    Science.gov (United States)

    Longino, John T; Branstetter, Michael G; Colwell, Robert K

    2014-01-01

    In tropical wet forests, ants are a large proportion of the animal biomass, but the factors determining abundance are not well understood. We characterized ant abundance in the litter layer of 41 mature wet forest sites spread throughout Central America (Chiapas, Guatemala, Honduras, Nicaragua, and Costa Rica) and examined the impact of elevation (as a proxy for temperature) and community species richness. Sites were intentionally chosen to minimize variation in precipitation and seasonality. From sea level to 1500 m ant abundance very gradually declined, community richness declined more rapidly than abundance, and the local frequency of the locally most common species increased. These results suggest that within this elevational zone, density compensation is acting, maintaining high ant abundance as richness declines. In contrast, in sites above 1500 m, ant abundance dropped abruptly to much lower levels. Among these high montane sites, community richness explained much more of the variation in abundance than elevation, and there was no evidence of density compensation. The relative stability of abundance below 1500 m may be caused by opposing effects of temperature on productivity and metabolism. Lower temperatures may decrease productivity and thus the amount of food available for consumers, but slower metabolisms of consumers may allow maintenance of higher biomass at lower resource supply rates. Ant communities at these lower elevations may be highly interactive, the result of continuous habitat presence over geological time. High montane sites may be ephemeral in geological time, resulting in non-interactive communities dominated by historical and stochastic processes. Abundance in these sites may be determined by the number of species that manage to colonize and/or avoid extinction on mountaintops.

  1. How ants drop out: ant abundance on tropical mountains.

    Directory of Open Access Journals (Sweden)

    John T Longino

    Full Text Available In tropical wet forests, ants are a large proportion of the animal biomass, but the factors determining abundance are not well understood. We characterized ant abundance in the litter layer of 41 mature wet forest sites spread throughout Central America (Chiapas, Guatemala, Honduras, Nicaragua, and Costa Rica and examined the impact of elevation (as a proxy for temperature and community species richness. Sites were intentionally chosen to minimize variation in precipitation and seasonality. From sea level to 1500 m ant abundance very gradually declined, community richness declined more rapidly than abundance, and the local frequency of the locally most common species increased. These results suggest that within this elevational zone, density compensation is acting, maintaining high ant abundance as richness declines. In contrast, in sites above 1500 m, ant abundance dropped abruptly to much lower levels. Among these high montane sites, community richness explained much more of the variation in abundance than elevation, and there was no evidence of density compensation. The relative stability of abundance below 1500 m may be caused by opposing effects of temperature on productivity and metabolism. Lower temperatures may decrease productivity and thus the amount of food available for consumers, but slower metabolisms of consumers may allow maintenance of higher biomass at lower resource supply rates. Ant communities at these lower elevations may be highly interactive, the result of continuous habitat presence over geological time. High montane sites may be ephemeral in geological time, resulting in non-interactive communities dominated by historical and stochastic processes. Abundance in these sites may be determined by the number of species that manage to colonize and/or avoid extinction on mountaintops.

  2. Pest repelling properties of ant pheromones

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2014-01-01

    Ants control pests via predation and physical deterrence; however, ant communication is based on chemical cues which may serve as warning signals to potential prey and other intruders. The presence of ant pheromones may, thus, be sufficient to repel pests from ant territories. This mini-review sh......-review shows that four out of five tested ant species deposit pheromones that repel herbivorous prey from their host plants.......Ants control pests via predation and physical deterrence; however, ant communication is based on chemical cues which may serve as warning signals to potential prey and other intruders. The presence of ant pheromones may, thus, be sufficient to repel pests from ant territories. This mini...

  3. Nectar Theft and Floral Ant-Repellence: A Link between Nectar Volume and Ant-Repellent Traits?

    Science.gov (United States)

    Ballantyne, Gavin; Willmer, Pat

    2012-01-01

    As flower visitors, ants rarely benefit a plant. They are poor pollinators, and can also disrupt pollination by deterring other flower visitors, or by stealing nectar. Some plant species therefore possess floral ant-repelling traits. But why do particular species have such traits when others do not? In a dry forest in Costa Rica, of 49 plant species around a third were ant-repellent at very close proximity to a common generalist ant species, usually via repellent pollen. Repellence was positively correlated with the presence of large nectar volumes. Repellent traits affected ant species differently, some influencing the behaviour of just a few species and others producing more generalised ant-repellence. Our results suggest that ant-repellent floral traits may often not be pleiotropic, but instead could have been selected for as a defence against ant thieves in plant species that invest in large volumes of nectar. This conclusion highlights to the importance of research into the cost of nectar production in future studies into ant-flower interactions. PMID:22952793

  4. Depresion: Lo Que Toda Mujer Debe Saber (Depression: What Every Woman Should Know).

    Science.gov (United States)

    National Inst. of Mental Health (DHHS), Bethesda, MD.

    This publication, written in Spanish, explains why women are at greater risk for depression than men. Types of depressive illnesses are explained along with the symptoms. It states that some women are predisposed genetically to depression but biochemical, environmental, psychological, and social factors also often contribute to its occurrence.…

  5. Hepatitis C: Lo que debe saber (Hepatitis C: What You Need to Know)

    Centers for Disease Control (CDC) Podcasts

    2013-05-07

    Este podcast está basado en el informe Vital Signs de los CDC de mayo del 2013. Trata sobre la hepatitis C, una infección viral grave, y la necesidad de que todas las personas nacidas entre 1945 y 1964 se hagan una prueba de detección.  Created: 5/7/2013 by Centers for Disease Control and Prevention (CDC).   Date Released: 5/7/2013.

  6. Evolutionary History of Saber-Toothed Cats Based on Ancient Mitogenomics.

    Science.gov (United States)

    Paijmans, Johanna L A; Barnett, Ross; Gilbert, M Thomas P; Zepeda-Mendoza, M Lisandra; Reumer, Jelle W F; de Vos, John; Zazula, Grant; Nagel, Doris; Baryshnikov, Gennady F; Leonard, Jennifer A; Rohland, Nadin; Westbury, Michael V; Barlow, Axel; Hofreiter, Michael

    2017-11-06

    Saber-toothed cats (Machairodontinae) are among the most widely recognized representatives of the now largely extinct Pleistocene megafauna. However, many aspects of their ecology, evolution, and extinction remain uncertain. Although ancient-DNA studies have led to huge advances in our knowledge of these aspects of many other megafauna species (e.g., mammoths and cave bears), relatively few ancient-DNA studies have focused on saber-toothed cats [1-3], and they have been restricted to short fragments of mitochondrial DNA. Here we investigate the evolutionary history of two lineages of saber-toothed cats (Smilodon and Homotherium) in relation to living carnivores and find that the Machairodontinae form a well-supported clade that is distinct from all living felids. We present partial mitochondrial genomes from one S. populator sample and three Homotherium sp. samples, including the only Late Pleistocene Homotherium sample from Eurasia [4]. We confirm the identification of the unique Late Pleistocene European fossil through ancient-DNA analyses, thus strengthening the evidence that Homotherium occurred in Europe over 200,000 years later than previously believed. This in turn forces a re-evaluation of its demography and extinction dynamics. Within the Machairodontinae, we find a deep divergence between Smilodon and Homotherium (∼18 million years) but limited diversity between the American and European Homotherium specimens. The genetic data support the hypothesis that all Late Pleistocene (or post-Villafrancian) Homotherium should be considered a single species, H. latidens, which was previously proposed based on morphological data [5, 6]. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Pest repellent properties of ant pheromones

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2012-01-01

    of ant pheromones may be sufficient to repel pest insects from ant territories. The study of ant semiochemicals is in its infancy, yet, evidence for their potential use in pest management is starting to build up. Pheromones from four of five tested ant species have been shown to deter herbivorous insect...... prey and competing ant species are also deterred by ant deposits, whereas ant symbionts may be attracted to them. Based on these promising initial findings, it seems advisable to further elucidate the signaling properties of ant pheromones and to test and develop their use in future pest management....

  8. PNL. PROGRAMACIÓN NEUROLINGÜÍSTICA, ONTOLOGÍA DE LA GERENCIA MODERNA

    Directory of Open Access Journals (Sweden)

    John Orlando Crissien Castillo

    2004-07-01

    Full Text Available El juego gerencial ha cambiado y requiere gerentes líderes y administradores. Las cosas se administran, la gente se lidera, se gerencia. El gerente líder del siglo XXI se debe formar, capacitar, entrenar en aquellas habilidades requeridas por este nuevo entorno. Debe desarrollar dos nuevos tipos de competencias: primero, como gerente integral debe contar con capacidad directiva; segundo, si los conocimientos regulares ya no son suficientes, necesita ahora desarrollar su inteligencia emocional. Este artículo plantea por qué el super gerente de hoy necesita utilizar su cerebro de manera más eficaz y saber cómo funciona. No saber cómo funciona el cerebro humano es como utilizar un supercomputador con el software más complejo del mundo sólo para escribir cartas. Los seres humanos sólo usamos un mínimo porcentaje del potencial cerebral. Braintec es la “tecnología cerebral” que estudia cómo funciona el cerebro y cómo manejarlo. Aprenda a usar su cerebro para gerenciar: hágalo por variar.

  9. REFLEXIONES SOBRE SABER , REVISTA CIENTÍFICA DEL CONSEJO DE INVESTIGACION DE LA UNIVERSIDAD DE ORIENTE I REFLECTIONS ON SABER , SCIENTIFIC JOURNAL OF THE RESEARCH COUNCIL OF THE UNIVERSIDAD DE ORIENTE

    Directory of Open Access Journals (Sweden)

    GERÓNIMO OJEDA CRESPO

    2018-05-01

    Full Text Available Presents a brief account of the beginnings of the Universidad de Oriente, higher education institution seated in the eastern territory of Venezuela; as well as also related to attempts to establish a “editorial policy” in the different campuses university, periodical publications of scientific character. In describing the path of SABER periodical publication, multidisciplinary, financed and edited by the Research Council , presents a sequence of events that have marked both their presence and their contribution to the university community. Finally we suggest a number of actions to continue the important work of SABER as scientific journal of the Universidad de Oriente.

  10. CONHECIMENTO-SOLIDARIEDADE COMO UM SABER DOCENTE NA MODALIDADE EAD: ATITUDES, VALORES E CONDIÇÕES

    Directory of Open Access Journals (Sweden)

    Regina Trilho Otero Xavier

    2008-07-01

    Full Text Available O presente artigo relata uma investigação que pesquisa a construção do conhecimento-solidariedade em EAD. O objetivo principal do estudo é contribuir para a implementação de ações pedagógicas em EAD na perspectiva do conhecimento-solidariedade. A partir, principalmente, dos referenciais de Boaventura Santos, Jean Piaget e Yves de La Taille procura-se compreender o que vem a ser o conhecimento-solidariedade, bem como os valores e saberes que favorecem seu desenvolvimento em ações pedagógicas de professores e alunos em EAD. Os estudos apontam que agir de acordo com o conhecimento-solidariedade exige competência cognitiva (saber ser solidário, competência afetiva (querer ser solidário e, ainda, um contexto favorável (poder ser solidário. As conclusões evidenciam que o conhecimento–solidariedade, em ações pedagógicas na modalidade EAD, está fortemente vinculado aos saberes éticos, técnicos, pedagógicos, comunicacionais e de gestão; que se trata de um saber construído progressivamente, em experiências permeadas por respeito mútuo, reciprocidade e empatia, tendo a cooperação como principal estratégia. Mas, e fundamentalmente, que a ocorrência de ações, na perspectiva do conhecimento-solidariedade, é dependente de contextos individuais de origem complexa, pois envolvem a interação de vários aspectos interligados (como: hábitos, valores, sentimentos, capacidades,... e de contextos coletivos dinâmicos (como ambientes cooperativos ou coercitivos, entre pares ou “superiores”, na presença de autoridade que incentiva ou que desfavorece a solidariedade. Palavras-chave: EaD, solidariedade, saberes docentes.

  11. Saber popular: sua existência no meio universitário Saber popular: su existencia en el medio universitario Popular wisdom: its existence in the university environment

    Directory of Open Access Journals (Sweden)

    Maria Alves Barbosa

    2004-12-01

    Full Text Available Mitos e crendices estão presentes hodiernamente, apesar do desenvolvimento da ciência e da tecnologia, principalmente na busca por soluções de problemas que fogem ao entendimento humano. Objetivou-se verificar na comunidade universitária a existência de crendices e mitos, investigando suas origens, influências, adoção e credibilidade, correlacionando-os com o nível de conhecimento dos indivíduos. Pesquisa descritivo-analítica desenvolvida em Unidades de Ensino da Área de Saúde da Universidade Federal de Goiás. Seguiu-se a técnica de análise de conteúdo para análise dos dados. Foram criadas duas categorias: Atitudes Pessoais Relacionadas a Crenças e Influências e Superação das Crenças. Concluiu-se que há colisão entre os saberes popular e científico, gerando a exclusão do saber popular, sua manutenção "velada", ou mesmo, a aliança dos saberes.Mitos y creencias están presentes actualmente, a pesar del desarrollo de la ciencia y de la tecnología, principalmente en la búsqueda por soluciones de problemas que escapan al entendimiento humano. El estudio tuvo como objetivo verificar en la comunidad universitaria la existencia de creencias, mitos y otras prácticas populares, investigando sus orígenes, influencias, adopción, credibilidad y correlacionándolos con el nivel de conocimiento de los individuos. La investigación cuya naturaleza es descriptiva-analítica, fue desarrollada en Unidades de Enseñanza del Área de Salud de la Universidad Federal de Goiás. El grupo se constituye de profesores y estudiantes de los cursos del área de salud. Los resultados posibilitaron la creación de dos categorías, la primera, Actitudes personales relacionadas a Creencias, evidenció el poder de las prácticas populares y de las creencias sobre el comportamiento humano y la segunda, Influencias y Superación de las Creencias, permitió la comprensión del contento social y cultural del grupo investigado. Se concluye que

  12. Statistical comparisons of gravity wave features derived from OH airglow and SABER data

    Science.gov (United States)

    Gelinas, L. J.; Hecht, J. H.; Walterscheid, R. L.

    2017-12-01

    The Aerospace Corporation's near-IR camera (ANI), deployed at Andes Lidar Observatory (ALO), Cerro Pachon Chile (30S,70W) since 2010, images the bright OH Meinel (4,2) airglow band. The imager provides detailed observations of gravity waves and instability dynamics, as described by Hecht et al. (2014). The camera employs a wide-angle lens that views a 73 by 73 degree region of the sky, approximately 120 km x 120 km at 85 km altitude. Image cadence of 30s allows for detailed spectral analysis of the horizontal components of wave features, including the evolution and decay of instability features. The SABER instrument on NASA's TIMED spacecraft provides remote soundings of kinetic temperature profiles from the lower stratosphere to the lower thermosphere. Horizontal and vertical filtering techniques allow SABER temperatures to be analyzed for gravity wave variances [Walterscheid and Christensen, 2016]. Here we compare the statistical characteristics of horizontal wave spectra, derived from airglow imagery, with vertical wave variances derived from SABER temperature profiles. The analysis is performed for a period of strong mountain wave activity over the Andes spanning the period between June and September 2012. Hecht, J. H., et al. (2014), The life cycle of instability features measured from the Andes Lidar Observatory over Cerro Pachon on March 24, 2012, J. Geophys. Res. Atmos., 119, 8872-8898, doi:10.1002/2014JD021726. Walterscheid, R. L., and A. B. Christensen (2016), Low-latitude gravity wave variances in the mesosphere and lower thermosphere derived from SABER temperature observation and compared with model simulation of waves generated by deep tropical convection, J. Geophys. Res. Atmos., 121, 11,900-11,912, doi:10.1002/2016JD024843.

  13. Spectral wave analysis at the mesopause from SCIAMACHY airglow data compared to SABER temperature spectra

    Directory of Open Access Journals (Sweden)

    M. Ern

    2009-01-01

    Full Text Available Space-time spectral analysis of satellite data is an important method to derive a synoptic picture of the atmosphere from measurements sampled asynoptically by satellite instruments. In addition, it serves as a powerful tool to identify and separate different wave modes in the atmospheric data. In our work we present space-time spectral analyses of chemical heating rates derived from Scanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY hydroxyl nightglow emission measurements onboard Envisat for the years 2002–2006 at mesopause heights.

    Since SCIAMACHY nightglow hydroxyl emission measurements are restricted to the ascending (nighttime part of the satellite orbit, our analysis also includes temperature spectra derived from 15 μm CO2 emissions measured by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER instrument. SABER offers better temporal and spatial coverage (daytime and night-time values of temperature and a more regular sampling grid. Therefore SABER spectra also contain information about higher frequency waves.

    Comparison of SCIAMACHY and SABER results shows that SCIAMACHY, in spite of its observational restrictions, provides valuable information on most of the wave modes present in the mesopause region. The main differences between wave spectra obtained from these sensors can be attributed to the differences in their sampling patterns.

  14. La lectura del cuento y su relación con los futuros enseñantes de Primaria: análisis de la práctica cultural en el curriculum formativo

    Directory of Open Access Journals (Sweden)

    Amelia Benito del Valle Eskauriaza

    2017-06-01

    Full Text Available A través de este artículo, se analiza el lugar que ocupa la lectura y más concretamente la lectura del cuento, en el saber académico de los estudiantes de magisterio y futuros profesores de primaria. Para ello se ha llevado a cabo una investigación-acción en la universidad del País Vasco UPV-EHU entre los alumnos de segundo de Magisterio de Primaria durante el primer cuatrimestre del curso académico 2015-2016. Esta investigación-acción concierne a la puesta a punto del lugar que debe ocupar la lectura del cuento como práctica cultural, en el curriculum de la formación inicial de los futuros profesores de esta etapa de la educación.

  15. Argumentative skills of law students in the framework of the Saber-Pro tests

    Directory of Open Access Journals (Sweden)

    Rafael Alejandro Betancourt Durango

    2015-06-01

    Full Text Available In the context of university training of lawyers, argumentative skills are vital for the outstanding performance of these professionals in their work environment; so the State sphere has tended to design, collecting the Saber-Pro test model, generic and specific evaluation components that support the appropriation of reading and writing and literacy skills in law students who face the State exam. In this research paper it is intended to inform the academic community about the indicators of performance on Saber-Pro tests, reflected by the students attached to the Law Program at Institución Universitaria de Envigado, seen from the analysis of argumentative skills

  16. Swords and sabers during the Early Islamic Period

    Directory of Open Access Journals (Sweden)

    Alexander, David

    2001-12-01

    Full Text Available The present article offers a discussion on early swords and sabers during the Early Islamic Period, from the Topkap’ Sarayi collection to written, iconographic and archeological sources.

    El presente art’culo trata las espadas y sables utilizados en los primeros tiempos del Islam a partir de la colecció—n del Topkap’ Sarayi y de las fuentes escritas, iconogr‡ficas y arqueol—gicas.

  17. Plant lock and ant key: pairwise coevolution of an exclusion filter in an ant-plant mutualism.

    Science.gov (United States)

    Brouat, C; Garcia, N; Andary, C; McKey, D

    2001-10-22

    Although observations suggest pairwise coevolution in specific ant-plant symbioses, coevolutionary processes have rarely been demonstrated. We report on, what is to the authors' knowledge, the strongest evidence yet for reciprocal adaptation of morphological characters in a species-specific ant-plant mutualism. The plant character is the prostoma, which is a small unlignified organ at the apex of the domatia in which symbiotic ants excavate an entrance hole. Each myrmecophyte in the genus Leonardoxa has evolved a prostoma with a different shape. By performing precise measurements on the prostomata of three related myrmecophytes, on their specific associated ants and on the entrance holes excavated by symbiotic ants at the prostomata, we showed that correspondence of the plant and ant traits forms a morphological and behavioural filter. We have strong evidence for coevolution between the dimensions and shape of the symbiotic ants and the prostoma in one of the three ant-Leonardoxa associations.

  18. Saberes mapuche en la relación del hombre con la naturaleza: aportes para

    Directory of Open Access Journals (Sweden)

    Carlos Manuel Pacheco Huaiquifil

    2015-12-01

    Full Text Available El presente artículo tiene como objetivo elaborar una propuesta educativa de educación ambiental basada en los saberes ancestrales mapuche relacionados con el cuidado medioambiental.El estudio de tipo cualitativo,utiliza la Teoría Fundamentada. Se aplicaron 12 entrevistas a personas con ascendencia mapuche y que vive no han vivido en comunidades mapuche o sectores rurales. Los resultados identifican un con junto de conocimientos de cuidado y daño medioambiental y estrategias de enseñanza que permiten diseñar una propuesta de educación ambiental basada en estos saberes.

  19. Beyond ANT

    DEFF Research Database (Denmark)

    Jansen, Till

    2017-01-01

    Actor-Network-Theory (ANT) offers an ‘infra-language’ of the social that allows one to trace social relations very dynamically, while at the same time dissolving human agency, thus providing a flat and de-centred way into sociology. However, ANT struggles with its theoretical design that may lead...... us to reduce agency to causation and to conceptualize actor-networks as homogeneous ontologies of force. This article proposes to regard ANT’s inability to conceptualize reflexivity and the interrelatedness of different ontologies as the fundamental problem of the theory. Drawing on Günther......, it offers an ‘infra-language’ of reflexive relations while maintaining ANT’s de-centred approach. This would enable us to conceptualize actor-networks as non-homogeneous, dynamic and connecting different societal rationales while maintaining the main strengths of ANT....

  20. Dynamics of an ant-plant-pollinator model

    Science.gov (United States)

    Wang, Yuanshi; DeAngelis, Donald L.; Nathaniel Holland, J.

    2015-03-01

    In this paper, we consider plant-pollinator-ant systems in which plant-pollinator interaction and plant-ant interaction are both mutualistic, but there also exists interference of pollinators by ants. The plant-pollinator interaction can be described by a Beddington-DeAngelis formula, so we extend the formula to characterize plant-pollinator mutualisms, including the interference by ants, and form a plant-pollinator-ant model. Using dynamical systems theory, we show uniform persistence of the model. Moreover, we demonstrate conditions under which boundary equilibria are globally asymptotically stable. The dynamics exhibit mechanisms by which the three species could coexist when ants interfere with pollinators. We define a threshold in ant interference. When ant interference is strong, it can drive plant-pollinator mutualisms to extinction. Furthermore, if the ants depend on pollination mutualism for their persistence, then sufficiently strong ant interference could lead to their own extinction as well. Yet, when ant interference is weak, plant-ant and plant-pollinator mutualisms can promote the persistence of one another.

  1. Using Ants as bioindicators: Multiscale Issues in Ant Community Ecology

    Directory of Open Access Journals (Sweden)

    Alan Andersen

    1997-06-01

    Full Text Available Ecological patterns and processes are characteristically scale dependent, and research findings often cannot be translated easily from one scale to another. Conservation biology is challenged by a lack of congruence between the spatial scales of ecological research (typically involving small plots and land management (typically involving whole landscapes. Here, I discuss spatial scaling issues as they relate to an understanding of ant communities and, consequently, their use as bioindicators in land management. Our perceptions of fundamental patterns and processes in ant communities depend on scale: taxa that are behaviorally dominant at one scale are not necessarily so at others, functional groups recognized at one scale are often inappropriate for others, and the role of competition in community structure depends on the scale of analysis. Patterns of species richness and composition, and the ability of total richness to be estimated by surrogates, are all also scale dependent. Ant community ecology has a tradition of detailed studies in small plots, but the use of ants as bioindicators requires a predictive understanding of community structure and dynamics at a range of spatial scales. Such an appreciation of ant communities and their most effective use as bioindicators is best served by studies integrating results from plot-scale research with the broad-scale paradigms of biogeography, systematics, and evolutionary biology.

  2. Revised Correlation between Odin/OSIRIS PMC Properties and Coincident TIMED/SABER Mesospheric Temperatures

    Science.gov (United States)

    Feofilov, A. G.; Petelina, S. V.; Kutepov, A. A.; Pesnell, W. D.; Goldberg, R. A.; Llewellyn, E. J.; Russell, J. M.

    2006-01-01

    The Optical Spectrograph and Infrared Imaging System (OSIRIS) instrument on board the Odin satellite detects Polar Mesospheric Clouds (PMCs) through the enhancement in the limb-scattered solar radiance. The Sounding of the Atmosphere using the Broadband Emission Radiometry (SABER) instrument on board the TIMED satellite is a limb scanning infrared radiometer that measures temperature and vertical profiles and energetic parameters for minor constituents in the mesosphere and lower thermosphere. The combination of OSIRIS and SABER data has been previously used to statistically derive thermal conditions for PMC existence [Petelina et al., 2005]. a, A.A. Kutepov, W.D. Pesnell, In this work, we employ the simultaneous common volume measurements of PMCs by OSIRIS and temperature profiles measured by SABER for the Northern Hemisphere summers of 2002-2005 and corrected in the polar region by accounting for the vibrational-vibrational energy exchange among the CO2 isotopes [Kutepov et al., 2006]. For each of 20 coincidences identified within plus or minus 1 degree latitude, plus or minus 2 degrees longitude and less than 1 hour time the frost point temperatures were calculated using the corresponding SABER temperature profile and water vapor densities of 1,3, and 10 ppmv. We found that the PMC presence and brightness correlated only with the temperature threshold that corresponds to the frost point. The absolute value of the temperature below the frost point, however, didn't play a significant role in the intensity of PMC signal for the majority of selected coincidences. The presence of several bright clouds at temperatures above the frost point is obviously related to the limitation of the limb geometry when some near- or far-field PMCs located at higher (and warmer) altitudes appear to be at lower altitudes.

  3. Ecosystem services delivered by weaver ants

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    Weaver ants (Oecopgylla spp.) are increasingly being utilized as efficient biocontrol agents in a number of tropical tree crops, as they prey on pest insects and increase yields. However, recent studies and a review of the literature reveal that a number of other services may derive from the pres......Weaver ants (Oecopgylla spp.) are increasingly being utilized as efficient biocontrol agents in a number of tropical tree crops, as they prey on pest insects and increase yields. However, recent studies and a review of the literature reveal that a number of other services may derive from...... the presence of these ants. First of all, the chemical footprint left by the high density of ants in managed host trees may results in additional benefits. (i) Ant deposits may lead to improved fruit quality, e.g. increased sugar content, (ii) ant deposits may deter important pests (chemical deterrence) from...... crops, and lastly, (iii) ant waste products deposited ias anal spots contain urea that may be taken up by plant leaves and in this way fertilize ant-plants. On top of chemical services, weaver ants have been shown to reduce plant disease incidence via competitive exclusion of other ant species because...

  4. Ant-lepidopteran associations along African forest edges

    Science.gov (United States)

    Dejean, Alain; Azémar, Frédéric; Libert, Michel; Compin, Arthur; Hérault, Bruno; Orivel, Jérôme; Bouyer, Thierry; Corbara, Bruno

    2017-02-01

    Working along forest edges, we aimed to determine how some caterpillars can co-exist with territorially dominant arboreal ants (TDAAs) in tropical Africa. We recorded caterpillars from 22 lepidopteran species living in the presence of five TDAA species. Among the defoliator and/or nectarivorous caterpillars that live on tree foliage, the Pyralidae and Nymphalidae use their silk to protect themselves from ant attacks. The Notodontidae and lycaenid Polyommatinae and Theclinae live in direct contact with ants; the Theclinae even reward ants with abundant secretions from their Newcomer gland. Lichen feeders (lycaenid; Poritiinae), protected by long bristles, also live among ants. Some lycaenid Miletinae caterpillars feed on ant-attended membracids, including in the shelters where the ants attend them; Lachnocnema caterpillars use their forelegs to obtain trophallaxis from their host ants. Caterpillars from other species live inside weaver ant nests. Those of the genus Euliphyra (Miletinae) feed on ant prey and brood and can obtain trophallaxis, while those from an Eberidae species only prey on host ant eggs. Eublemma albifascia (Erebidae) caterpillars use their thoracic legs to obtain trophallaxis and trophic eggs from ants. Through transfer bioassays of last instars, we noted that herbivorous caterpillars living in contact with ants were always accepted by alien conspecific ants; this is likely due to an intrinsic appeasing odor. Yet, caterpillars living in ant shelters or ant nests probably acquire cues from their host colonies because they were considered aliens and killed. We conclude that co-evolution with ants occurred similarly in the Heterocera and Rhopalocera.

  5. The metapleural gland of ants

    DEFF Research Database (Denmark)

    Yek, Sze Huei; Mueller, Ulrich G

    2011-01-01

    The metapleural gland (MG) is a complex glandular structure unique to ants, suggesting a critical role in their origin and ecological success. We synthesize the current understanding of the adaptive function, morphology, evolutionary history, and chemical properties of the MG. Two functions......-compressible invagination of the integument and the secretion is thought to ooze out passively through the non-closable opening of the MG or is groomed off by the legs and applied to target surfaces. MG loss has occurred repeatedly among the ants, particularly in the subfamilies Formicinae and Myrmicinae, and the MG...... is more commonly absent in males than in workers. MG chemistry has been characterized mostly in derived ant lineages with unique biologies (e.g. leafcutter ants, fire ants), currently precluding any inferences about MG chemistry at the origin of the ants. A synthetic approach integrating functional...

  6. Foliar uptake of nitrogen from ant fecal droplets: an overlooked service to ant plants

    DEFF Research Database (Denmark)

    Pinkalski, Christian Alexander Stidsen; Jensen, Karl-Martin Vagn; Damgaard, Christian Frølund

    2018-01-01

    and subsequently deposited fecal droplets on the seedlings, coffee leaves showed increased levels of 15N and total N compared to control plants without ants. This was evident for both exposed leaves and leaves covered in plastic bags (i.e. not directly exposed to ants). Thus, N from ant excretions was absorbed...

  7. Saberes docente para o ensino de ciências e biologia

    Directory of Open Access Journals (Sweden)

    Cibele Bender Raio

    2017-09-01

    Full Text Available Este trabalho apresenta os saberes que configuram um bom professor. Estes saberes, caracterizados pela mudança nos padrões de participação do professor na prática pedagógica, os quais não são construídos apenas durante o curso de formação inicial, mas sim ao longo da história de vida do educador. A partir dos conhecimentos de Paulo Freire e de Edgar Morin são sugeridos temas para possíveis práticas no ensino de ciências e de biologia. Dessa forma, uma educação em que o professor só deposita o conteúdo no aluno deve ser substituída por aquela que instiga a curiosidade, valoriza a opinião a sua opinião, considera seus sentimentos e promove a sua autonomia, ou seja, converte o educando em um agente transformador da sua própria realidade. Para isso, o professor precisa atuar com sentimentalidade, criticidade e autoridade, sem autoritarismo. Além disso, é papel do educador mostrar que não há conhecimento ileso ao erro ou a ilusão. Ele, também, precisa trabalhar o contexto local em relação a um conteúdo global. É um saber ensinar a condição do humano como unidade do universo e educar sobre a identidade terrena. Considerando, além disso, as incertezas dos acontecimentos e a ética humana. As discussões aqui apresentadas são sugestões para o desenvolvimento de práticas de ensino. No entanto, o professor deve elaborá-las de acordo com o seu ambiente de trabalho e seu público.

  8. Ángulos planos: Por qué el radián debe tener una medida igual a la unidad?

    Directory of Open Access Journals (Sweden)

    Héctor Oscar Di Rocco

    2009-05-01

    Full Text Available http://dx.doi.org/10.5007/2175-7941.2009v26n1p136 En este artículo se trata de un asunto que genera polémicas en la enseñanza de la Física: por qué el radián debe tener asignada una medida igual a la unidad. El radián no es una de las tantas posibles unidades de ángulos, sino la única para la cual se cumplen las relaciones trigonométricas y del Cálculo Infinitesimal, aunque la Geometría Analítica no necesite de esta unidad. Se muestra que la respuesta debe buscarse en algunos sencillos conceptos del Cálculo Infinitesimal, donde las nociones analíticas se hacen independientes de las geométricas.

  9. Marcos de referencia de saberes digitales

    Directory of Open Access Journals (Sweden)

    Alberto Ramírez Martinell

    2015-07-01

    Full Text Available En este artículo se muestra una recopilación de estándares, indicadores y recomendaciones elaboradas por organizaciones como OCDE, UNESCO, ISTE y ECDL sobre el uso de Tecnologías de la Información y Comunicación (TIC. Esta información la presentamos mediante el análisis de contenidos de cada uno de los cuatro criterios a partir de tres enfoques: saberes informáticos, literacidad informacional y ciudadanía digital, ya que –según las organizaciones estudiadas– esto, acompañado del desarrollo de competencias de tipo transversal, aseguran un impacto positivo de las TIC en el contexto académico.

  10. Perlongher: sexualidad y saber. Búsqueda ensayística y emergencia intelectual

    Directory of Open Access Journals (Sweden)

    Javier Gasparri

    2013-12-01

    Full Text Available El presente artículo se centra en la obra del argentino Néstor Perlongher (1949 – 1992 para intentar rastrear e interrogar un pensamiento sobre la sexualidad, sin descuidar las implicancias literarias del mismo, y en el marco de conjeturas críticas en torno a su singular ejercicio intelectual como así también el recurso al ensayo como forma de articulación conceptual. En esta dirección, la experiencia-límite de Perlongher permite vislumbrar (e hipotetizar consecuencias y proyecciones literarias y políticas, afi rmando así una ética. Se tratará, entonces, de una búsqueda esencialmente escrituraria del saber (en el marco de los saberes actuales a Perlongher, sobre todo las líneas posestructuralistas, y asimismo con la atención puesta en el activismo de disidencia sexual pero que también compromete y se conjuga con la puesta del cuerpo en su afirmación vital.

  11. El psicoanálisis y el saber acerca de la subjetividad

    Directory of Open Access Journals (Sweden)

    Emma Guillermina Ruiz Martín del Campo

    2009-01-01

    Full Text Available Al alejarse de los métodos tradicionales de la medicina e introducir la escucha de sus pacientes aquejadas de síntomas histéricos para la comprensión de sus padecimientos, Freud realizó una ruptura epistemológica que implicó la introducción de lo subjetivo en el campo del saber. Él mismo anticipó el valor que la indagación acerca del inconsciente tendría como herramienta al servicio de las ciencias sociales. Aquí se plantean cuestiones como la relación del conocimiento que se califica de científico con la irracionalidad y con lo inagotable de nuestra ignorancia. Se muestra, a través de dos ejemplos, el potencial que significa en la búsqueda de saber el compromiso del investigador con todo lo que él es en su trabajo, o sea, la utilización de su subjetividad como herramienta de investigación.

  12. SABER Observations of the OH Meinel Airglow Variability Near the Mesopause

    Science.gov (United States)

    Marsh, Daniel R.; Smith, Anne K.; Mlynczak, Martin G.

    2005-01-01

    The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument, one of four on board the TIMED satellite, observes the OH Meinel emission at 2.0 m that peaks near the mesopause. The emission results from reactions between members of the oxygen and hydrogen chemical families that can be significantly affected by mesopause dynamics. In this study we compare SABER measurements of OH Meinel emission rates and temperatures with predictions from a 3-dimensional chemical dynamical model. In general, the model is capable of reproducing both the observed diurnal and seasonal OH Meinel emission variability. The results indicate that the diurnal tide has a large effect on the overall magnitude and temporal variation of the emission in low latitudes. This tidal variability is so dominant that the seasonal cycle in the nighttime emission depends very strongly on the local time of the analysis. At higher latitudes, the emission has an annual cycle that is due mainly to transport of oxygen by the seasonally reversing mean circulation.

  13. Saber arte para saber enseñar arte_la formación de los maestros de educación artística

    Directory of Open Access Journals (Sweden)

    Lucia Gouvêa Pimentel

    2009-04-01

    Full Text Available Para saber enseñar arte es necesario que el maestro de Educación Artística tenga conocimiento suficiente para que pueda escoger los contenidos y las metodologías más adecuadas al aprendizaje. Es importante dar a los maestros de Educación Artística la formación y condiciones adecuadas para que se tornen sujetos pensantes de su contexto y de sus acciones.

  14. Odorous house ants (Tapinoma sessile as back-seat drivers of localized ant decline in urban habitats.

    Directory of Open Access Journals (Sweden)

    Adam Salyer

    Full Text Available Invasive species and habitat disturbance threaten biodiversity worldwide by modifying ecosystem performance and displacing native organisms. Similar homogenization impacts manifest locally when urbanization forces native species to relocate or reinvade perpetually altered habitat. This study investigated correlations between ant richness and abundance in response to urbanization and the nearby presence of invasive ant species, odorous house ants (Tapinoma sessile, within its native region. Surveying localized ant composition within natural, semi-natural, and urban habitat supported efforts to determine whether T. sessile appear to be primary (drivers threats as instigators or secondary (passengers threats as inheritors of indigenous ant decline. Sampling 180 sites, evenly split between all habitats with and without T. sessile present, yielded 45 total species. Although urbanization and T. sessile presence factors were significantly linked to ant decline, their interaction correlated to the greatest reduction of total ant richness (74% and abundance (81%. Total richness appeared to decrease from 27 species to 18 when natural habitat is urbanized and from 18 species to 7 with T. sessile present in urban plots. Odorous house ant presence minimally influenced ant communities within natural and semi-natural habitat, highlighting the importance of habitat alteration and T. sessile presence interactions. Results suggest urbanization releases T. sessile from unknown constraints by decreasing ant richness and competition. Within urban environment, T. sessile are pre-adapted to quickly exploit new resources and grow to supercolony strength wherein T. sessile drive adjacent biodiversity loss. Odorous house ants act as passengers and drivers of ecological change throughout different phases of urban 'invasion'. This progression through surviving habitat alteration, exploiting new resources, thriving, and further reducing interspecific competition supports a

  15. Dimensión integral e interdisciplinaria del concepto de comportamiento del consumidor

    OpenAIRE

    Gil Hernández, Cleysi Yumara; Torres Estrada, Isabel Cristina; López Torres, Zulima Azeneth

    2013-01-01

    Este artículo busca analizar el aporte teórico que la economía, la antropología,la psicología, la sociología y la estética hacen al estudio del concepto decomportamiento del consumidor.El estudio del comportamiento del consumidor debe buscar una miradaintegral, que permita, desde diferentes saberes y disciplinas, comprender alsujeto, su entorno y sus prácticas de consumo.El estudio del consumidor no debe supeditarse exclusivamente a los momentosdel consumo; su comprensión implica un análisis ...

  16. NUEVAS HERRAMIENTAS DE COMUNICACIÓN FAVORECEN LA ENSEÑANZA MÉDICA

    Directory of Open Access Journals (Sweden)

    Frank Lizaraso Caparó

    2014-06-01

    Full Text Available La aparición de tecnologías de la educación y la comunicación, nos han permitido ir mejorando el proceso de enseñanza-aprendizaje en las distintas Facultades de Medicina Humana. Tanto a nivel del pre, como en el posgrado. El médico del futuro, no sólo debe ser capaz de adquirir, organizar, relacionar y aplicar el conocimiento sino que por sobre todo, debe saber comunicar y difundir su experiencia para formar parte activa de un mundo globalizado y sin límites.

  17. La comunicación en las fuerzas de seguridad del Estado

    Directory of Open Access Journals (Sweden)

    María de las Mercedes Cancelo San Martín

    2014-12-01

    Full Text Available La búsqueda de legitimización social de las instituciones es una de las claves de la comunicación institucional. Independiente de su actividad organizacional la comunicación debe ser la nueva interpretación del concepto de responsabilidad social. Existe un deber: el de comunicar, pues en cualquier sociedad democrática toda actividad organizacional empieza con el consentimiento del público y éste debe saber si las fuerzas de seguridad cumplen las funciones para las que fueron creadas. Presenta algunos estudios de caso.

  18. Microsatellite primers for fungus-growing ants

    DEFF Research Database (Denmark)

    Villesen, Palle; Gertsch, P J; Boomsma, JJ

    2002-01-01

    We isolated five polymorphic microsatellite loci from a library of two thousand recombinant clones of two fungus-growing ant species, Cyphomyrmex longiscapus and Trachymyrmex cf. zeteki. Amplification and heterozygosity were tested in five species of higher attine ants using both the newly...... developed primers and earlier published primers that were developed for fungus-growing ants. A total of 20 variable microsatellite loci, developed for six different species of fungus-growing ants, are now available for studying the population genetics and colony kin-structure of these ants....

  19. Microsatellite Primers for Fungus-Growing Ants

    DEFF Research Database (Denmark)

    Villesen Fredsted, Palle; Gertsch, Pia J.; Boomsma, Jacobus Jan (Koos)

    2002-01-01

    We isolated five polymorphic microsatellite loci from a library of two thousand recombinant clones of two fungus-growing ant species, Cyphomyrmex longiscapus and Trachymyrmex cf. zeteki. Amplification and heterozygosity were tested in five species of higher attine ants using both the newly...... developed primers and earlier published primers that were developed for fungus-growing ants. A total of 20 variable microsatellite loci, developed for six different species of fungus-growing ants, are now available for studying the population genetics and colony kin-structure of these ants....

  20. Os saberes dos professores-referência no ensino de contabilidade

    Directory of Open Access Journals (Sweden)

    Gilberto José Miranda

    2012-08-01

    Full Text Available O presente estudo tem como propósito avaliar os saberes predominantes nos docentes percebidos como professores-referência pelos alunos de um curso de Graduação em Ciências Contábeis de uma universidade pública brasileira. O estudo justifica-se pelas recentes e significativas mudanças no contexto da Contabilidade no Brasil. Para alcance desse propósito, estruturou-se uma pesquisa qualitativa, em que foram utilizadas as seguintes estratégias de pesquisa e técnicas de coleta de dados: (i pesquisa bibliográfica em obras relevantes que tratam do tema; (ii pesquisa documental nas avaliações dos professores feitas pela instituição; (iii questionários aplicados aos alunos do último ano; (iv grupo focal com parte do grupo de alunos respondentes dos questionários; e (v entrevista semiestruturada com professores apontados pelos alunos como docentes de referência. Amparados pelas discussões tecidas acerca de saberes, competências e conhecimentos necessários à docência (Shulman, 1986; Garcia, 1992; Freire, 2000; Pimenta, 1998; Pimenta & Anastasiou, 2002; Gauthier, Martineau, Desbiens, Malo, & Simard, 1998; Tardif, 2003; Cunha, 2004; Masetto, 1998; Braslavsky, 1999; Perrenoud, 2000; Zabalza, 2006 e aqueles necessários ao ensino de contabilidade (Antonelli, Colauto, & Cunha, 2012; Miranda, 2011; Catapan, Colauto, & Sillas, 2011; Vasconcelos, 2010; Slomsky, 2009; Araujo & Santana, 2008; Celerino & Pereira, 2008; Andere & Araújo, 2008; Laffin, 2005, bem como pesquisas sobre professores exemplares (Young & Shaw, 1999; Lowman, 2007, verificaram-se os seguintes resultados: as disciplinas responsáveis pelas experiências mais significativas de aprendizagem, durante o curso, eram as percebidas como base do curso (Contabilidade Básica, Intermediária e Avançada e que apresentavam maior aplicação prática. As razões principais para escolha dos docentes de referência foram: didática ou metodologia de ensino, atitudes e qualidades

  1. Ant Colony Optimization for Control

    NARCIS (Netherlands)

    Van Ast, J.M.

    2010-01-01

    The very basis of this thesis is the collective behavior of ants in colonies. Ants are an excellent example of how rather simple behavior on a local level can lead to complex behavior on a global level that is beneficial for the individuals. The key in the self-organization of ants is communication

  2. New nighttime retrievals of O(3P) and OH densities in the mesosphere/lower thermosphere using SABER/TIMED observations

    Science.gov (United States)

    Panka, P.; Kutepov, A. A.; Kalogerakis, K. S.; Janches, D.; Feofilov, A.; Rezac, L.; Marsh, D. R.; Yigit, E.

    2017-12-01

    We present first retrievals of O(3P) and OH densities in the mesosphere/lower thermosphere (MLT) using SABER/TIMED OH 2.0 and 1.6 μm limb emission observations. Recently, Kaufmann et al. [2014] reported that current SABER O(3P) densities are on average 30% higher compared to other observations. In this study we applied new detailed non-LTE model [Panka et al. 2017] of nighttime OH(v), which accounts for the new mechanism OH(v≥5)+O(3P)→O(1D)+OH(v-5) of energy transfer recently suggested by Sharma et al. [2015] and confirmed through laboratory studies by Kalogerakis et al. [2016]. Based on this model we developed a new self-consistent two channel retrieval approach for O(3P) and OH density. Using this approach, we retrieved O(3P) densities that are 10-40% lower than current SABER O(3P), as well as total OH density which is retrieved for the first time using SABER observations. We compare our retrieveals with the results of other observations and models. As it was recently shown by Panka et al. [2017], the new mechanism of OH quenching produces a significant pumping of CO2 4.3 µm emission. We discuss the effects these new O(3P) and OH retrievals have on the nighttime CO2 density retrievals from the SABER 4.3 µm channel.

  3. Partial incompatibility between ants and symbiotic fungi in two sympatric species of Acromyrmex leaf-cutting ants.

    Science.gov (United States)

    Bot, A N; Rehner, S A; Boomsma, J J

    2001-10-01

    We investigate the nature and duration of incompatibility between certain combinations of Acromyrmex leaf-cutting ants and symbiotic fungi, taken from sympatric colonies of the same or a related species. Ant-fungus incompatibility appeared to be largely independent of the ant species involved, but could be explained partly by genetic differences among the fungus cultivars. Following current theoretical considerations, we develop a hypothesis, originally proposed by S. A. Frank, that the observed incompatibilities are ultimately due to competitive interactions between genetically different fungal lineages, and we predict that the ants should have evolved mechanisms to prevent such competition between cultivars within a single garden. This requires that the ants are able to recognize unfamiliar fungi, and we show that this is indeed the case. Amplified fragment length polymorphism genotyping further shows that the two sympatric Acromyrmex species share each other's major lineages of cultivar, confirming that horizontal transfer does occasionally take place. We argue and provide some evidence that chemical substances produced by the fungus garden may mediate recognition of alien fungi by the ants. We show that incompatibility between ants and transplanted, genetically different cultivars is indeed due to active killing of the novel cultivar by the ants. This incompatibility disappears when ants are force-fed the novel cultivar for about a week, a result that is consistent with our hypothesis of recognition induced by the resident fungus and eventual replacement of incompatibility compounds during force-feeding.

  4. Sick ants become unsociable

    DEFF Research Database (Denmark)

    Bos, Nicky Peter Maria; Lefevre, T.; Jensen, A.B.

    2012-01-01

    Parasites represent a severe threat to social insects, which form high-density colonies of related individuals, and selection should favour host traits that reduce infection risk. Here, using a carpenter ant (Camponotus aethiops) and a generalist insect pathogenic fungus (Metarhizium brunneum), we...... show that infected ants radically change their behaviour over time to reduce the risk of colony infection. Infected individuals (i) performed less social interactions than their uninfected counterparts, (ii) did not interact with brood anymore and (iii) spent most of their time outside the nest from...... day 3 post-infection until death. Furthermore, infected ants displayed an increased aggressiveness towards non-nestmates. Finally, infected ants did not alter their cuticular chemical profile, suggesting that infected individuals do not signal their physiological status to nestmates. Our results...

  5. Interactive effects of soil-dwelling ants, ant mounds and simulated grazing on local plant community composition

    NARCIS (Netherlands)

    Veen, G.F.; Olff, H.

    2011-01-01

    Interactions between aboveground vertebrate herbivores and subterranean yellow meadow ants (Lasius flavus) can drive plant community patterns in grassland ecosystems. Here, we study the relative importance of the presence of ants (L. flavus) and ant mounds under different simulated grazing regimes

  6. Chapter 7: Lessons, Conclusions, and Implications of the Saber-Tooth Project.

    Science.gov (United States)

    Ward, Phillip; Doutis, Panayiotis; Evans, Sharon A.

    1999-01-01

    Summarizes findings from the Saber-Tooth Project related to systemic change and student learning, concluding that vision is everything; workplace conditions must be addressed at multiple levels; strong relationships exist among planning, teaching, and assessment; and improvement in reform may occur due to the cessation of business as usual. This…

  7. Roadside Survey of Ants on Oahu, Hawaii

    Science.gov (United States)

    Tong, Reina L.; Grace, J. Kenneth; Krushelnycky, Paul D.

    2018-01-01

    Hawaii is home to over 60 ant species, including five of the six most damaging invasive ants. Although there have been many surveys of ants in Hawaii, the last island-wide hand-collection survey of ants on Oahu was conducted in 1988–1994. In 2012, a timed hand-collection of ants was made at 44 sites in a systematic, roadside survey throughout Oahu. Ants were identified and species distribution in relation to elevation, precipitation and soil type was analyzed. To assess possible convenience sampling bias, 15 additional sites were sampled further from roads to compare with the samples near roads. Twenty-four species of ants were found and mapped; Pheidole megacephala (F.), Ochetellus glaber (Mayr), and Technomyrmex difficilis Forel were the most frequently encountered ants. For six ant species, a logistic regression was performed with elevation, average annual precipitation, and soil order as explanatory variables. O. glaber was found in areas with lower precipitation around Oahu. Paratrechina longicornis (Latrielle) and Tetramorium simillimum (Smith, F.) were found more often in lower elevations and in areas with the Mollisol soil order. Elevation, precipitation, and soil type were not significant sources of variation for P. megacephala, Plagiolepis alluaudi Emery, and T. difficilis. P. megacephala was associated with fewer mean numbers of ants where it occurred. Ant assemblages near and far from roads did not significantly differ. Many species of ants remain established on Oahu, and recent invaders are spreading throughout the island. Mapping ant distributions contributes to continued documentation and understanding of these pests. PMID:29439503

  8. Dealing with water deficit in Atta ant colonies: large ants scout for water while small ants transport it

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Da-Silva

    2012-07-01

    Leafcutter ants (Atta sexdens rubropilosa (Forel 1908 have an elaborate social organization, complete with caste divisions. Activities carried out by specialist groups contribute to the overall success and survival of the colony when it is confronted with environmental challenges such as dehydration. Ants detect variations in humidity inside the nest and react by activating several types of behavior that enhance water uptake and decrease water loss, but it is not clear whether or not a single caste collects water regardless of the cost of bringing this resource back to the colony. Accordingly, we investigated water collection activities in three colonies of Atta sexdens rubropilosa experimentally exposed to water stress. Specifically, we analyzed whether or not the same ant caste foraged for water, regardless of the absolute energetic cost (distance of transporting this resource back to the colony. Our experimental design offered water sources at 0 m, 1 m and 10 m from the nest. We studied the body size of ants near the water sources from the initial offer of water (time  =  0 to 120 min, and tested for specialization. We observed a reduction in the average size and variance of ants that corroborated the specialization hypothesis. Although the temporal course of specialization changed with distance, the final outcome was similar among distances. Thus, we conclude that, for this species, a specialist (our use of the word “specialist” does not mean exclusive task force is responsible for collecting water, regardless of the cost of transporting water back to the colony.

  9. Air-filled left hepatic duct: the saber sign as an aid to the radiographic diagnosis of pneumobilia

    International Nuclear Information System (INIS)

    Lewandowski, B.J.; Withers, C.; Winsberg, F.

    1984-01-01

    In the supine patient, gas rises to the left hepatic duct. Radiographically, this can be recognized as a saber-shaped lucency to the right of the spine. In a retrospective analysis and review of the radiographs of 40 patients shown to have gas in the biliary tree by ultrasound (US), computed tomography (CT), or radiography, the diagnosis could be made in 37 patients. In 18 of these 37 cases pneumobilia could be identified by the saber-shaped distribution of gas

  10. The evolution of genome size in ants

    Directory of Open Access Journals (Sweden)

    Spagna Joseph C

    2008-02-01

    Full Text Available Abstract Background Despite the economic and ecological importance of ants, genomic tools for this family (Formicidae remain woefully scarce. Knowledge of genome size, for example, is a useful and necessary prerequisite for the development of many genomic resources, yet it has been reported for only one ant species (Solenopsis invicta, and the two published estimates for this species differ by 146.7 Mb (0.15 pg. Results Here, we report the genome size for 40 species of ants distributed across 10 of the 20 currently recognized subfamilies, thus making Formicidae the 4th most surveyed insect family and elevating the Hymenoptera to the 5th most surveyed insect order. Our analysis spans much of the ant phylogeny, from the less derived Amblyoponinae and Ponerinae to the more derived Myrmicinae, Formicinae and Dolichoderinae. We include a number of interesting and important taxa, including the invasive Argentine ant (Linepithema humile, Neotropical army ants (genera Eciton and Labidus, trapjaw ants (Odontomachus, fungus-growing ants (Apterostigma, Atta and Sericomyrmex, harvester ants (Messor, Pheidole and Pogonomyrmex, carpenter ants (Camponotus, a fire ant (Solenopsis, and a bulldog ant (Myrmecia. Our results show that ants possess small genomes relative to most other insects, yet genome size varies three-fold across this insect family. Moreover, our data suggest that two whole-genome duplications may have occurred in the ancestors of the modern Ectatomma and Apterostigma. Although some previous studies of other taxa have revealed a relationship between genome size and body size, our phylogenetically-controlled analysis of this correlation did not reveal a significant relationship. Conclusion This is the first analysis of genome size in ants (Formicidae and the first across multiple species of social insects. We show that genome size is a variable trait that can evolve gradually over long time spans, as well as rapidly, through processes that may

  11. Retrieval of Kinetic Temperature and Carbon Dioxide Abundance from Non-Local Thermodynamic Equilibrium Limb Emission Measurements made by the SABER Experiment on the TIMED Satellite

    Science.gov (United States)

    Mertens, Christopher J.; Mlynczak, Martin G.; Lopez-Puertas, Manuel; Wintersteiner, Peter P.; Picard, Richard H.; Winick, Jeremy R.; Gordley, Larry L.; Russell, James M., III

    2002-01-01

    The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) experiment was launched onboard the TIMED satellite in December, 2001. SABER is designed to provide measurements of the key radiative and chemical sources and sinks of energy in the mesosphere and lower thermosphere (MLT). SABER measures Earth limb emission in 10 broadband radiometer channels ranging from 1.27 micrometers to 17 micrometers. Measurements are made both day and night over the latitude range from 54 deg. S to 87 deg. N with alternating hemisphere coverage every 60 days. In this paper we concentrate on retrieved profiles of kinetic temperature (T(sub k)) and CO2 volume mixing ratio (vmr), inferred from SABER-observed 15 micrometer and 4.3 micrometer limb emissions, respectively. SABER-measured limb radiances are in non-local thermodynamic equilibrium (non-LTE) in the MLT region. The complexity of non-LTE radiation transfer combined with the large volume of data measured by SABER requires new retrieval approaches and radiative transfer techniques to accurately and efficiently retrieve the data products. In this paper we present the salient features of the coupled non-LTE T(sub k)/CO2 retrieval algorithm, along with preliminary results.

  12. Are ant feces nutrients for plants? A metabolomics approach to elucidate the nutritional effects on plants hosting weaver ants

    DEFF Research Database (Denmark)

    Vidkjær, Nanna Hjort; Wollenweber, Bernd; Gislum, René

    2015-01-01

    Weaver ants (genus Oecophylla) are tropical carnivorous ant species living in high numbers in the canopies of trees. The ants excrete copious amounts of fecal matter on leaf surfaces, and these feces may provide nutrients to host trees. This hypothesis is supported by studies of ant......-plant interactions involving other ant species that have demonstrated the transfer of nutrients from ants to plants. In this 7-months study, a GC–MS-based metabolomics approach along with an analysis of total nitrogen and carbon levels was used to study metabolic changes in ant-hosting Coffea arabica plants compared...... with control plants. The results showed elevated levels of total nitrogen, amino acids, fatty acids, caffeine, and secondary metabolites of the phenylpropanoid pathway in leaves from ant-hosting plants. Minor effects were observed for sugars, whereas little or no effect was observed for organic acids, despite...

  13. Revistas, consumos, alimentación y saberes femeninos. La propuesta de Damas y Damitas, Argentina, 1939-1944

    Directory of Open Access Journals (Sweden)

    Paula Caldo

    2016-01-01

    Full Text Available El presente artículo aborda un aspecto puntual del abanico que se extiende en torno a la problemática de la transmisión de los saberes femeninos: la transmisión escrita del saber culinario y sus connotaciones teóricas, prácticas, performativas y económicas. Específicamente, nos concentraremos en la Argentina en el cruce de las décadas de los treinta y los cuarenta, recorte que coincide con la consolidación de la sociedad de consumo y con la irrupción en el mercado editorial de una revista femenina llamada Damas y Damitas, que tomaremos como referente empírico de nuestro análisis. En dicha publicación recuperamos el accionar de la ecónoma encargada de enseñar a cocinar pero también de prescribir un deber ser y un saber elegir (la marca a sus congéneres.

  14. The interactions of ants with their biotic environment.

    Science.gov (United States)

    Chomicki, Guillaume; Renner, Susanne S

    2017-03-15

    This s pecial feature results from the symposium 'Ants 2016: ant interactions with their biotic environments' held in Munich in May 2016 and deals with the interactions between ants and other insects, plants, microbes and fungi, studied at micro- and macroevolutionary levels with a wide range of approaches, from field ecology to next-generation sequencing, chemical ecology and molecular genetics. In this paper, we review key aspects of these biotic interactions to provide background information for the papers of this s pecial feature After listing the major types of biotic interactions that ants engage in, we present a brief overview of ant/ant communication, ant/plant interactions, ant/fungus symbioses, and recent insights about ants and their endosymbionts. Using a large molecular clock-dated Formicidae phylogeny, we map the evolutionary origins of different ant clades' interactions with plants, fungi and hemiptera. Ants' biotic interactions provide ideal systems to address fundamental ecological and evolutionary questions about mutualism, coevolution, adaptation and animal communication. © 2017 The Author(s).

  15. Saberes da enfermagem - a solidariedade como uma categoria essencial do cuidado Saberes de la enfermería - la solidaridad como una categoria esencial del cuidado Knowing of nursing - solidarity as an essencial category of care

    Directory of Open Access Journals (Sweden)

    Vera Regina Waldow

    2011-09-01

    Full Text Available Objetiva-se refletir sobre os saberes da enfermagem nos aspectos analíticos e sintéticos, segundo as novas perspectivas paradigmáticas, e destacar a solidariedade como uma das categorias do cuidado. A arte e a ciência da Enfermagem estão consubstanciadas pelo cuidado, assumido como o seu saber fazer. A solidariedade, por sua vez, elemento substancial do cuidado, é ressaltada neste texto, considerando a realidade atual, pois compõe o sentido moral e o exercício da cidadania.Su objetivo es reflexionar sobre los saberes de la Enfermería en sus aspectos analíticos y sintéticos, de acuerdo con las nuevas perspectivas paradigmáticas, y destacar la solidaridad como una de las categorías del cuidado. El arte y la ciencia de Enfermería están consustanciadas por el cuidado, asumido acá como su saber hacer. La solidaridad, por su vez, elemento esencial del cuidado, se enfatiza en el texto, teniendo en cuenta la realidad actual, que constituye el sentido moral y el ejercicio de la ciudadanía.This paper aims to reflect on the knowledge of nursing in synthetic and analytical aspects, according to new paradigmatic perspectives and emphasize solidarity as one of the categories of care. The art and science of nursing are consubstantiated by the care given in the present article as its know-how.Solidarity, in turn, substantial element of care is emphasized in the text, considering the current reality, because it makes up the moral sense and the exercise of citizenship.

  16. Saberes y poderes. Los grupos intelectuales en Colombia

    OpenAIRE

    Botero-Bernal, Andrés

    2011-01-01

    Este trabajo plantea una historia de la intelectualidad colombiana basada en ocho grandes grupos básicos, a saber: los próceres, los intelectuales gramáticos, los pedagogos y los críticos, los expertos, los intelectuales partidistas, los intelectuales filósofos, los científicos sociales y los intelectuales economistas. Esta clasificación fue hecha a partir de un esquema basado en profesiones (en especial, la del jurista, pero sin dejar de lado el militar, el médico, el economista, etc.) y en ...

  17. Antônio Gonçalves Gomide: uma semiologia das doenças nervosas no Brasil Antônio Gonçalves Gomide: a semiotics of nervous illnesses in Brazil

    Directory of Open Access Journals (Sweden)

    Simone Santos de Almeida Silva

    2010-12-01

    Full Text Available Analisa o parecer médico de Antônio Gonçalves Gomide, publicado em 1814. Trata-se de análise crítica realizada pelo médico, a fim de compreender as manifestações de uma beata, Germana Maria da Purificação, que viveu em Minas Gerais, entre os séculos XVIII e XIX. No texto o médico se contrapõe a um exame realizado por dois cirurgiões que declararam o estado da beata como sobrenatural. A intenção é analisar o parecer situando a concepção da patologia da beata para destacar a importância do documento na compreensão da constituição dos saberes médicos no Brasil. Procura-se ressaltar o fato de o texto ter sido um dos primeiros publicados sobre a medicina mental, podendo ser considerado um dos escritos fundadores dessa medicina que se inaugurava no Brasil no século XIX.In 1814, physician Antônio Gonçalves Gomide published a medical report in which he offered a critical analysis of the manifestations of a beata (holy woman, Germana Maria da Purificação, who lived in Minas Gerais between the eighteenth and nineteenth centuries. The doctor disagreed with the examination performed by two surgeons, who declared that the state of the beata was "supernatural." The present article analyzes the doctor's report and situates his view of the holy woman's pathology. The text was one of the first ever published on mental medicine and as such stands both as one of the foundational writings of a field that emerged in Brazil in the nineteenth century and also as a valuable source in understanding the formation of medical knowledge in this country.

  18. Saúde mental: reconstruindo saberes em enfermagem

    Directory of Open Access Journals (Sweden)

    Francisca Bezerra de Oliveira

    2003-02-01

    Full Text Available O manicômio, apesar de criticado, reformado ou mesmo negado, ainda é uma prática preponderante no cuidado às pessoas com transtornos mentais. Tal prática tem como princípio básico o isolamento do doente mental, contrariando todas as possibilidades de assistência centrada num humanismo ético. Este ensaio procura interpretar a institucionalização do asilo, da psiquiatria, da doença mental e o processo da reforma psiquiátrica, buscando contribuir para as reflexões acerca da desinstitucionalização e dos saberes e práticas de enfermagem em saúde mental.

  19. Chemically armed mercenary ants protect fungus-farming societies

    DEFF Research Database (Denmark)

    Adams, Rachelle Martha Marie; Liberti, Joanito; Illum, Anders A.

    2013-01-01

    guest ants are sufficient to kill raiders that invariably exterminate host nests without a cohabiting guest ant colony. We also show that the odor of guest ants discourages raider scouts from recruiting nestmates to host colonies. Our results imply that Sericomyrmex fungus-growers obtain a net benefit......The ants are extraordinary in having evolved many lineages that exploit closely related ant societies as social parasites, but social parasitism by distantly related ants is rare. Here we document the interaction dynamics among a Sericomyrmex fungus-growing ant host, a permanently associated...... parasitic guest ant of the genus Megalomyrmex, and a raiding agro-predator of the genus Gnamptogenys. We show experimentally that the guest ants protect their host colonies against agro-predator raids using alkaloid venom that is much more potent than the biting defenses of the host ants. Relatively few...

  20. A cellular automata model for ant trails

    Indian Academy of Sciences (India)

    In this study, the unidirectional ant traffic flow with U-turn in an ant trail was inves- tigated using ... the literature, it was considered in the model that (i) ant colony consists of two kinds of ants, good- ... ponents without a central controller [8].

  1. Using pleometrosis (multiple queens) and pupae transplantation to boost weaver ant (Oecophylla smaragdina) colony growth in ant nurseries

    DEFF Research Database (Denmark)

    Offenberg, Hans Joachim; Nielsen, Mogens Gissel; Peng, Renkang

    2011-01-01

    Weaver ants (Oecophylla spp.) are increasingly being used for biocontrol and are targeted for future production of insect protein in ant farms. An efficient production of live ant colonies may facilitate the utilization of these ants but the production of mature colonies is hampered by the long...... and no transplantation. Thus, in ant nurseries the use of multiple queens during nest founding as well as transplantation of pupae from foreign colonies may be utilised to decrease the time it takes to produce a colony ready for implementation....

  2. Ant-plants and fungi: a new threeway symbiosis.

    Science.gov (United States)

    Defossez, Emmanuel; Selosse, Marc-André; Dubois, Marie-Pierre; Mondolot, Laurence; Faccio, Antonella; Djieto-Lordon, Champlain; McKey, Doyle; Blatrix, Rumsaïs

    2009-06-01

    Symbioses between plants and fungi, fungi and ants, and ants and plants all play important roles in ecosystems. Symbioses involving all three partners appear to be rare. Here, we describe a novel tripartite symbiosis in which ants and a fungus inhabit domatia of an ant-plant, and present evidence that such interactions are widespread. We investigated 139 individuals of the African ant-plant Leonardoxa africana for occurrence of fungus. Behaviour of mutualist ants toward the fungus within domatia was observed using a video camera fitted with an endoscope. Fungi were identified by sequencing a fragment of their ribosomal DNA. Fungi were always present in domatia occupied by mutualist ants but never in domatia occupied by opportunistic or parasitic ants. Ants appear to favour the propagation, removal and maintenance of the fungus. Similar fungi were associated with other ant-plants in Cameroon. All belong to the ascomycete order Chaetothyriales; those from L. africana formed a monophyletic clade. These new plant-ant-fungus associations seem to be specific, as demonstrated within Leonardoxa and as suggested by fungal phyletic identities. Such tripartite associations are widespread in African ant-plants but have long been overlooked. Taking fungal partners into account will greatly enhance our understanding of symbiotic ant-plant mutualisms.

  3. Food source quality and ant dominance hierarchy influence the outcomes of ant-plant interactions in an arid environment

    Science.gov (United States)

    Flores-Flores, Rocío Vianey; Aguirre, Armando; Anjos, Diego V.; Neves, Frederico S.; Campos, Ricardo I.; Dáttilo, Wesley

    2018-02-01

    In this study, we conducted a series of experiments in a population of Vachellia constricta (Fabaceae) in the arid Tehuacan-Cuicatláan valley, Mexico, in order to evaluate if the food source quality and ant dominance hierarchy influence the outcomes of ant-plant interactions. Using an experiment with artificial nectaries, we observed that ants foraging on food sources with higher concentration of sugar are quicker in finding and attacking potential herbivorous insects. More specifically, we found that the same ant species may increase their defence effectiveness according to the quality of food available. These findings indicate that ant effectiveness in plant protection is context-dependent and may vary according to specific individual characteristics of plants. In addition, we showed that competitively superior ant species tend to dominate plants in periods with high nectar activity, emphasizing the role of the dominance hierarchy structuring ant-plant interactions. However, when high sugar food sources were experimentally available ad libitum, the nocturnal and competitively superior ant species, Camponotus atriceps, did not dominate the artificial nectaries during the day possibly due to limitation of its thermal tolerance. Therefore, temporal niche partitioning may be allowing the coexistence of two dominant ant species (Camponotus rubritorax during the day and C. atriceps at night) on V. constricta. Our findings indicate that the quality of the food source, and temporal shifts in ant dominance are key factors which structure the biotic plant defences in an arid environment.

  4. A gestão da informação na análise de Foucault sobre as relações poder-saber

    Directory of Open Access Journals (Sweden)

    Sérgio Paulo Maravilhas-Lopes

    2013-07-01

    Full Text Available Foucault mostrou como o poder e o saber se interrelacionam e de que forma ele é exercido sobre os indivíduos na sociedade, através de tecnologias que permitem a vigilância, cada vez gerando mais saber. Tentaremos ligar a vigilância ao conhecimento e poder que permitem obter, bem como o uso de tecnologias em moldes eletrónicos para o fazer. Tendo Foucault apontado como o poder e o saber se interrelacionam e de que forma é ele exercido sobre os indivíduos na sociedade, cada vez gerando mais saber, procuraremos mostrar essas relações, objetivos dessa coerção e formas de o fazer, apelando à utilização das novas tecnologias e fazendo uso da gestão da informação para acumular e exercitar esse saber que se revelará em mais poder para quem o detém. Desde sempre o conhecimento e a informação foram uma vantagem para quem dela dispunha, a diferença é que no passado conhecíamos bem os nossos vigilantes e agora, nos nossos dias, simplesmente nem sequer sabemos por quem somos vigiados, e o poder que isso pode exercer sobre as nossas vidas. Concluiremos com uma alusão ao papel da gestão da informação na obtenção e utilização desse saber para que melhor se exerça o poder.

  5. Persistence of pollination mutualisms in the presence of ants.

    Science.gov (United States)

    Wang, Yuanshi; Wang, Shikun

    2015-01-01

    This paper considers plant-pollinator-ant systems in which the plant-pollinator interaction is mutualistic but ants have both positive and negative effects on plants. The ants also interfere with pollinators by preventing them from accessing plants. While a Beddington-DeAngelis (BD) formula can describe the plant-pollinator interaction, the formula is extended in this paper to characterize the pollination mutualism under the ant interference. Then, a plant-pollinator-ant system with the extended BD functional response is discussed, and global dynamics of the model demonstrate the mechanisms by which pollination mutualism can persist in the presence of ants. When the ant interference is strong, it can result in extinction of pollinators. Moreover, if the ants depend on pollination mutualism for survival, the strong interference could drive pollinators into extinction, which consequently lead to extinction of the ants themselves. When the ant interference is weak, a cooperation between plant-ant and plant-pollinator mutualisms could occur, which promotes survival of both ants and pollinators, especially in the case that ants (respectively, pollinators) cannot survive in the absence of pollinators (respectively, ants). Even when the level of ant interference remains invariant, varying ants' negative effect on plants can result in survival/extinction of both ants and pollinators. Therefore, our results provide an explanation for the persistence of pollination mutualism when there exist ants.

  6. Long-range downstream effects of urban runoff and acid mine drainage in the Debed River, Armenia: insights from lead isotope modeling

    International Nuclear Information System (INIS)

    Kurkjian, Robert; Dunlap, Charles; Flegal, A. Russell

    2004-01-01

    Lead concentrations and isotopic compositions measured along 80 km of the Debed River in the Republic of Armenia provide new insights into the geochemical and physical controls on riparian Pb transport by allowing comparison of the long-range, downstream impacts of acid mine drainage with runoff from an industrialized city. The modern background Pb concentration in Armenian surface waters is estimated to be ∼0.01 μg/L, based on analyses of remote alpine rivers in Armenia. The lead concentration in the Debed River is 8 μg/L (800 times background) after passing through Vanadzor, the second largest industrial city in Armenia; it then decreases to 1 μg/L before the Debed River flows into the Alaverdi mining district. There, the Debed River receives waters from two mining drainage streams with Pb concentrations >3000 μg/L, but those concentrations decrease 3 orders of magnitude to ∼3 μg/L by the time the river exits Armenia and flows into the Republic of Georgia. Isotope mixing plots show shifts in Pb isotope composition as the river flows out of Vanadzor, evidencing the mixture of an average terrestrial Pb composition ( 206 Pb/ 207 Pb ∼ 1.17; 208 Pb/ 207 Pb ∼ 2.45) with past leaded gasoline and other industrial Pb emissions retained in the river's sediments within that region ( 208 Pb/ 207 Pb ≤ 2.45). The isotopic composition again shifts (e.g., 208 Pb/ 207 Pb ≥ 2.46) as the river passes through the Alaverdi mining district, where isotopic ratios in the water are characteristic of Pb in the area's massive sulfide deposits. Modeling both downstream elemental concentrations and Pb isotopic compositions further resolves the physical and chemical behavior of the contaminants in the river system. A multi-element model of concentration gradients in the acid mine drainage streams indicates Pb is attenuated by Al(OH) 3 precipitation (54% of the loss) and by adsorption onto other particles settling out of the water column (46% of the loss). Modeling of Pb

  7. Riding with the ants

    NARCIS (Netherlands)

    Duarte, A. P. M.; Attili-Angelis, D.; Baron, N. C.; Groenewald, Johannes Z.; Crous, Pedro W.; Pagnocca, F. C.

    Isolates of Teratosphaeriaceae have frequently been found in the integument of attine ants, proving to be common and diverse in this microenvironment. The LSU phylogeny of the ant-isolated strains studied revealed that they cluster in two main lineages. The first was associated with the genus

  8. O SABER MÉDICO NA DIALÉTICA DA SALVAÇÃO: controle e utopia do poder medicalizante

    Directory of Open Access Journals (Sweden)

    André Sousa Trindade

    2016-07-01

    Full Text Available O presente artigo utiliza como fundamento teórico a análise sobre o saber médico realizada no livro de Michel Foucault O nascimento da clínica e a conferência de 1974, A crise da medicina ou antimedicina. A priori, partirei das seguintes premissas: a construção hegemônica do saber médico a partir do fim do século XVIII; e do poder que a medicina através do saber médico passou a exercer sobre os corpos doentes e não-doentes, alterando assim, a própria estrutura da vida, forçando os corpos à uma reconfiguração de corporeidade vigente na modernidade. Em suma, analisaremos o saber médico frente ao seu processo histórico e como esse saber apropriou-se de áreas externas à medicina influenciando diretamente na criação de políticas públicas, e na própria economia. É de vital interesse objetivar e problematizar todo o arcabouço medicinal, e mostrar uma dualidade nociva, de interesses políticos e econômicos, que são adeptos de uma dialética constante entre salvação, controle e utopia da vida. Palavras-chave: Foucault; Medicina; Saber médico; Corpo.   MEDICAL KNOWLEDGE IN THE DIALECTIC OF SALVATION: Control and utopia of medicalizante power ABSTRACT This article uses the theoretical basis for analysis of medical know held in Michel Foucault's book The Birth of the Clinic and the 1974 conference, The crisis of medicine or antimedicina. A priori, leave the following assumptions: the hegemonic construction of medical knowledge from the late eighteenth century; and power that medicine through medical know began to exert on sick bodies and non-patients, thus changing the very structure of life, forcing the body to a reconfiguration of the current embodiment of modernity. In short, we analyze medical know against its historical process and how this know appropriated outdoors medicine directly influencing the creation of public policies, and the economy itself. It is of vital interest to objectify and discuss all the medical

  9. El profesional de enfermería ante el duelo por muerte perinatal

    Directory of Open Access Journals (Sweden)

    Carmen Stella Martínez Dávalos

    2018-03-01

    Full Text Available Introducción: Enfermería cuida al ser humano en la salud y en la enfermedad, desde la concepción hasta la muerte. En el área de obstetricia, es determinante el cuidado a la puérpera y la actitud del profesional, especialmente cuando el producto de la concepción fallece antes de nacer o en los primeros minutos de vida. Objetivo: Determinar la relación que existe entre la actitud del Profesional de Enfermería ante el manejo del duelo en su factor cognitivo y conductual y el cuidado ofrecido a la puérpera en duelo por muerte perinatal en su factor necesidades psicológicas y necesidades espirituales. Métodos: Fue realizado en las Unidades de Atención del Departamento de Ginecobstetricia del Hospital Universitario “Dr. Antonio María Pineda” de Barquisimeto, Estado Lara. Se utilizó un diseño no experimental, tipo transeccional correlacional/causal, el análisis de los datos se realizó a través del test de Chí cuadrado y Fischer. Resultados: Predominan los sentimientos negativos hacia la muerte por parte de los Profesionales de Enfermería, no siendo determinantes en el incremento de la eficiencia o deficiencia en la atención prestada.  Se evidencio un vacío teórico en cuanto los conocimientos y destrezas que debe manejar el profesional con respecto a la muerte, el duelo y como enfrentar estos, aun cuando el 70% de los profesionales son egresados universitarios. Conclusiones: Es necesario revisar los currículos de enfermería y capacitar en ejercicio sobre el manejo del duelo. Asimismo, crear grupos de apoyo para los profesionales de salud y los padres que sufren una perdida perinatal.

  10. saberes sócio-culturais

    Directory of Open Access Journals (Sweden)

    Karina Machado Siqueira

    2006-01-01

    Full Text Available La investigación tuvo como objetivo identificar conductas adoptadas por los clientes antes de buscar los servicios de la salud y evidenciar los cambios de comportamiento cuanto a las creencias populares relacionadas a la prevención y la curación de las enfermedades, posterior a la orientación profesional. Estudio cualitativo, de tipo descriptivo-exploratorio, desarrollado en Goiânia - GO. La recolecta de dados fue realizada por medio de la entrevista individual junto a los usuarios de tres servicios del Sistema Único de Salud. Se dectecto que antes de buscar los servicios de salud, los clientes utilizaban los recursos populares como tés, curanderismo, baños y emplastos en la prevención y el tratamiento de las enfermedades. Se evidenció que ellos no abandonan la práctica popular, a pesar de la orientación médica, porque todavia creen en su eficacia. Se concluye que el cambio de hábitos relacionados a la salud es un proceso difícil siendo aún necesario respetar las tradiciones y opiniones del usuario al establecerse conductas y tratamientos.

  11. The importance of ants in cave ecology, with new records and behavioral observations of ants in Arizona caves

    Directory of Open Access Journals (Sweden)

    Robert B. Pape

    2016-09-01

    Full Text Available The importance of ants as elements in cave ecology has been mostly unrecognized. A global list of ant species recorded from caves, compiled from a review of existing literature, is presented. This paper also reviews what is currently known about ants occurring in Arizona (USA caves. The diversity and distribution represented in these records suggests ants are relatively common cave visitors (trogloxenes. A general utilization of caves by ants within both temperate and tropical latitudes may be inferred from this combined evidence. Observations of ant behavior in Arizona caves demonstrate a low level and sporadic, but persistent, use of these habitats and their contained resources by individual ant colonies. Documentation of Neivamyrmex sp. preying on cave-inhabiting arthropods is reported here for the first time. Observations of hypogeic army ants in caves suggests they may not penetrate to great vertical depth in search of prey, but can be persistent occupants in relatively shallow, horizontal sections of caves where they may prey on endemic cave animals. First cave records for ten ant species are reported from Arizona caves. These include two species of Neivamyrmex (N. nigrescens Cresson and Neivamyrmex sp.; Formicidae: Dorylinae, four myrmicines (Pheidole portalensis Wilson, Pheidole cf. porcula Wheeler, Solenopsis aurea Wheeler and Stenamma sp. Westwood, one dolichoderine (Forelius keiferi Wheeler and three formicines (Lasius arizonicus Wheeler, L. sitiens Wilson, and Camponotus sp. Mayr.

  12. Ant-plant-homopteran mutualism: how the third partner affects the interaction between a plant-specialist ant and its myrmecophyte host

    Science.gov (United States)

    Gaume, L.; McKey, D.; Terrin, S.

    1998-01-01

    By estimating relative costs and benefits, we explored the role of the homopteran partner in the protection mutualism between the myrmecophyte Leonardoxa africana T3, the ant Aphomomyrmex afer, and sap-sucking homopterans tended by ants in the tree's swollen hollow twigs. The ants obtain nest sites and food from their host-plant (food is obtained either directly by extrafloral nectar or indirectly via homopterans). Aphomomyrmex workers patrol the young leaves of L. africana T3 and protect them against phytophagous insects. Because ants tended, either solely or primarily, coccids in some trees and pseudococcids in others, we were able to study whether the nature of the interaction was dependent on the identity of the third partner. First, the type of homopteran affects the benefits to the tree of maintaining a large ant colony. Larger colony size (relative to tree size) confers greater protection against herbivory; this relationship is more pronounced for trees whose ants tend pseudococcids than for those in which ants tend coccids. Second, for trees (and associated ant colonies) of comparable size, homopteran biomass was much larger in trees harbouring coccids than in trees with pseudococcids. Thus, the cost to the tree of maintaining ants may be greater when ants are associated with coccids. The net benefits to the plant of maintaining ants appear to be much greater with pseudococcids as the third partner. To explore how the type of homopteran affects functioning of the system, we attempted to determine which of the resources (nest sites, extrafloral nectar, and homopterans) is likely to limit ant colony size. In trees where ants tended coccids, ant-colony biomass was strongly dependent on the number of extrafloral nectaries. In contrast, in trees whose ants tended only pseudococcids, colony biomass was not related to the number of nectaries and was most strongly determined by the volume of available nest sites. We present hypotheses to explain how the type of

  13. Relaciones entre saberes políticos, participación política y educación política: Aportes de la investigación psicológica Relations between political knowledge, political participation and Political education: Contributions from psychological research

    Directory of Open Access Journals (Sweden)

    Alicia M. Lenzi

    2008-12-01

    Full Text Available Se examina la vinculación entre saberes políticos, participación política y educación política desde la ciencia política y la investigación psicológica de los conceptos de democracia y gobierno. El análisis indica que la democracia representativa otorga escaso espacio a la participación política ciudadana, y los aportes de investigaciones en psicología social, del desarrollo y educacional evidencian que los saberes políticos indispensables para una participación autónoma, resultan críticos. Aunque las representaciones sociales de democracia juveniles muestran la aceptación de valores democráticos, jóvenes y adultos revelan saberes políticos indiferenciados sobre democracia y gobierno, incluso entre docentes que enseñan esas nociones. Ante tal panorama y limitaciones de la democracia representativa, la educación política constituye una alternativa para formar ciudadanos conscientes, autónomos, activos participantes capaces de transformar la sociedad.The relationship among political knowledge, political participation and political education is examined from both political science and psychological research on the concepts of democracy and government. The analysis indicates that representative democracy gives little place to citizens for political participation. Also, contributions from research by social, developmental and, educational psychology, show that the essential knowledge to autonomous political participation turn to be critical. Although youth`s social representations of democracy show the acceptance of democratic values, youngs and adults reveal undifferentiated knowledge about democracy and government, even among teachers who teach these concepts. From such scenario and limitations of representative democracy, political education is an alternative to prepare aware, autonomous citizens; active participants able to change society.

  14. La sociedad del conocimiento: inclusión o exclusión

    Directory of Open Access Journals (Sweden)

    Herminia Moreno Ríos

    2012-01-01

    Full Text Available En la historia de todas las sociedades, el conocimiento ha sido monopolizado por una élite, que lo utiliza para conservar el poder, se crearon limitantes para excluir a la masa de los saberes relevantes que otorgan la supremacía a unos y confinan a la mayoría a un trabajo físico o menos remunerado. En la actualidad surge el término Sociedad del Conocimiento para designar a nuestra sociedad, denominación que pareciera poner al alcance de todos tan preciado saber, con este trabajo pretendemos analizar si este beneficio es para todos, o es una forma disfrazada para continuar excluyendo y marginando a una gran parte de la sociedad, ya que la realidad muestra solo a una humanidad que tiene mayor acceso a la información, por la tecnología de la comunicación y el Internet, pero esa información aún debe transformarse en conocimiento utilitario, lo que en realidad existe es una sociedad de la información, que realmente no asegura que se pueda compartir con todos, los beneficios que brinda el conocimiento conductor de las sociedades, únicamente ofrece los saberes necesarios para competir en un mundo globalizado en donde cada individuo, según sus capacidades y competencias, debe encontrar su lugar.

  15. Ensino de conceitos químicos em um enfoque CTS a partir de saberes populares

    Directory of Open Access Journals (Sweden)

    Ricardo Luiz Zanotto

    Full Text Available Resumo: O presente artigo objetiva apresentar resultados de um estudo realizado sobre a utilização de saberes populares como ponto de partida para o ensino de conceitos químicos, articulando os diversos saberes sob o enfoque CTS. O trabalho foi realizado com 30 alunos da 3ª série do ensino médio de um colégio da rede estadual de ensino, da região sul do Paraná, Brasil. A abordagem metodológica foi a qualitativa, de natureza interpretativa, com observação participante. A coleta de dados se deu por meio de questionários, apresentação e discussão dos resultados das pesquisas bibliográficas, elaboração e análise de mapas conceituais, produção de infográficos (historinhas. A pesquisa demonstrou que a utilização dos saberes populares se constituiu num fator motivador e de apoio para a aprendizagem, possibilitando a contextualização dos conteúdos, tornando o ensino de Química mais atraente e significativo, facilitando, dessa maneira, a criação de estruturas cognitivas e mudanças de perfil conceitual.

  16. The distribution of weaver ant pheromones on host trees

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2007-01-01

    The visible anal spots deposited by Oecophylla smaragdina ants have been suggested to deter ant prey, affect interspecific competition and facilitate mutualists and parasites in tracking down Oecophylla ants. I measured the density of anal spots on host trees with and without ants and tested for ...... to leaves. Also there was a positive correlation between spot density and the likelihood of being detected by ants. Anal spots may thus function as reliable cues to interacting species and be an important factor in shaping the community around Oecophylla colonies.......The visible anal spots deposited by Oecophylla smaragdina ants have been suggested to deter ant prey, affect interspecific competition and facilitate mutualists and parasites in tracking down Oecophylla ants. I measured the density of anal spots on host trees with and without ants and tested...... for correlations between spot density, ant activity and the likelihood of being detected by an ant. Spots were only found on trees with ants. On ant-trees, spots were distributed throughout the trees but with higher densities in areas with high ant activity and pheromone densities were higher on twigs compared...

  17. SABERES POPULARES E EDUCAÇÃO CIENTÍFICA: UM OLHAR A PARTIR DA LITERATURA NA ÁREA DE ENSINO DE CIÊNCIAS

    Directory of Open Access Journals (Sweden)

    Patrícia Maria Azevedo Xavier

    2015-01-01

    Full Text Available Presentamos una mirada a la literatura en el campo de la Educación Científica acerca del tema saberes populares, buscando comprender como es tratado por la investigación en la Enseñanza de las Ciencias. Realizamos una revisión en seis revistas científicas brasileñas de la área de enseñanza/aprendizaje de las ciencias publicadas entre 2000 y 2012 y, en seguida, buscamos otras publicaciones de los autores encontrados. Después de la lectura de los trabajos, construimos cuatro categorías: Reflexiones teóricas; Nuevas alternativas didácticas; Intercambio de conocimientos con la comunidad; Investigación de las transformaciones a lo largo del tiempo. La investigación acerca de la inserción de saberes populares en la Enseñanza de las Ciencias es aún incipiente y se concentra en el desarrollo de nuevas alternativas didácticas, lo que muestra un movimiento en el sentido de aproximar, por medio de la investigación, los saberes populares del conocimiento escolar. Palabras clave: Saberes populares. Enseñanza de las Ciencias. Revisión de la literatura.Presentamos una mirada a la literatura en el campo de la Educación Científica acerca del tema saberes populares, buscando comprender como es tratado por la investigación en la Enseñanza de las Ciencias. Realizamos una revisión en seis revistas científicas brasileñas de la área de enseñanza/aprendizaje de las ciencias publicadas entre 2000 y 2012 y, en seguida, buscamos otras publicaciones de los autores encontrados. Después de la lectura de los trabajos, construimos cuatro categorías: Reflexiones teóricas; Nuevas alternativas didácticas; Intercambio de conocimientos con la comunidad; Investigación de las transformaciones a lo largo del tiempo. La investigación acerca de la inserción de saberes populares en la Enseñanza de las Ciencias es aún incipiente y se concentra en el desarrollo de nuevas alternativas didácticas, lo que muestra un movimiento en el sentido de

  18. Hablar y oír -Saber y poder. La poesía de Juana de Ibarbourou

    Directory of Open Access Journals (Sweden)

    María Teresa Aedo

    2016-04-01

    Full Text Available Esta investigación estudia la poesía de Juana de Ibarbourou desde Las lenguas de diamante (1919 hasta Mensajes del escriba (1953, en sus relaciones con las redes de fuerza de los discursos patriarcales. Describimos las estrategias lingüísticas propias del discurso ibarbouriano y el modo en que van configurando un decir y un saber distintos, que desarticulan la imagen convencional de mujer construida por los elementos fundamentales del saber-poder patriarcal, desenmascaran sus efectos de dominación y problematizan las posiciones establecidas para constituirse en sujeto discursivo en el marco de las relaciones de poder y de saber imperantes.   This reseach studies Juana de Ibarbourou's poetry from Las lenguas de diamante (1919 to Mensajes del Escriba (1953, in their relation with the patriarchal discourse of strengths. We describe the own ibarbourian discourse and the way in which it configures different saying and known. Furthermore, it desarticulates the wonen's conventional image built by the fundamental elements of patriarchal knowledge and power, unmasking the dominance and problematic effects at stablished social position. All this in order to constitute a discoursive subject within the knowledge -power imperative relations.

  19. Relative effects of disturbance on red imported fire ants and native ant species in a longleaf pine ecosystem

    DEFF Research Database (Denmark)

    Stuble, Katharine L.; Kirkman, L. Katherine; Carroll, C. Ronald

    2011-01-01

    and cases in which non-native species become established in intact (lacking extensive anthropogenic soil disturbance) communities and subsequently diminish the abundance and richness of native species is challenging on the basis of observation alone. The red imported fire ant (Solenopsis invicta......), an invasive species that occurs throughout much of the southeastern United States, is such an example. Rather than competitively displacing native species, fire ants may become established only in disturbed areas in which native species richness and abundance are already reduced. We used insecticide to reduce......, the abundance of native ants increased to levels comparable to those in control plots after 1 year. Our findings suggest that factors other than large reductions in ant abundance and species density (number of species per unit area) may affect the establishment of fire ants and that the response of native ants...

  20. Chemically armed mercenary ants protect fungus-farming societies

    Science.gov (United States)

    Adams, Rachelle M. M.; Liberti, Joanito; Illum, Anders A.; Jones, Tappey H.; Nash, David R.; Boomsma, Jacobus J.

    2013-01-01

    The ants are extraordinary in having evolved many lineages that exploit closely related ant societies as social parasites, but social parasitism by distantly related ants is rare. Here we document the interaction dynamics among a Sericomyrmex fungus-growing ant host, a permanently associated parasitic guest ant of the genus Megalomyrmex, and a raiding agro-predator of the genus Gnamptogenys. We show experimentally that the guest ants protect their host colonies against agro-predator raids using alkaloid venom that is much more potent than the biting defenses of the host ants. Relatively few guest ants are sufficient to kill raiders that invariably exterminate host nests without a cohabiting guest ant colony. We also show that the odor of guest ants discourages raider scouts from recruiting nestmates to host colonies. Our results imply that Sericomyrmex fungus-growers obtain a net benefit from their costly guest ants behaving as a functional soldier caste to meet lethal threats from agro-predator raiders. The fundamentally different life histories of the agro-predators and guest ants appear to facilitate their coexistence in a negative frequency-dependent manner. Because a guest ant colony is committed for life to a single host colony, the guests would harm their own interests by not defending the host that they continue to exploit. This conditional mutualism is analogous to chronic sickle cell anemia enhancing the resistance to malaria and to episodes in human history when mercenary city defenders offered either net benefits or imposed net costs, depending on the level of threat from invading armies. PMID:24019482

  1. Chemically armed mercenary ants protect fungus-farming societies.

    Science.gov (United States)

    Adams, Rachelle M M; Liberti, Joanito; Illum, Anders A; Jones, Tappey H; Nash, David R; Boomsma, Jacobus J

    2013-09-24

    The ants are extraordinary in having evolved many lineages that exploit closely related ant societies as social parasites, but social parasitism by distantly related ants is rare. Here we document the interaction dynamics among a Sericomyrmex fungus-growing ant host, a permanently associated parasitic guest ant of the genus Megalomyrmex, and a raiding agro-predator of the genus Gnamptogenys. We show experimentally that the guest ants protect their host colonies against agro-predator raids using alkaloid venom that is much more potent than the biting defenses of the host ants. Relatively few guest ants are sufficient to kill raiders that invariably exterminate host nests without a cohabiting guest ant colony. We also show that the odor of guest ants discourages raider scouts from recruiting nestmates to host colonies. Our results imply that Sericomyrmex fungus-growers obtain a net benefit from their costly guest ants behaving as a functional soldier caste to meet lethal threats from agro-predator raiders. The fundamentally different life histories of the agro-predators and guest ants appear to facilitate their coexistence in a negative frequency-dependent manner. Because a guest ant colony is committed for life to a single host colony, the guests would harm their own interests by not defending the host that they continue to exploit. This conditional mutualism is analogous to chronic sickle cell anemia enhancing the resistance to malaria and to episodes in human history when mercenary city defenders offered either net benefits or imposed net costs, depending on the level of threat from invading armies.

  2. Storm/Quiet Ratio Comparisons Between TIMED/SABER NO (sup +)(v) Volume Emission Rates and Incoherent Scatter Radar Electron Densities at E-Region Altitudes

    Science.gov (United States)

    Fernandez, J. R.; Mertens, C. J.; Bilitza, D.; Xu, X.; Russell, J. M., III; Mlynczak, M. G.

    2009-01-01

    Broadband infrared limb emission at 4.3 microns is measured by the TIMED/SABER instrument. At night, these emission observations at E-region altitudes are used to derive the so called NO+(v) Volume Emission Rate (VER). NO+(v) VER can be derived by removing the background CO2(v3) 4.3 microns radiance contribution using SABER-based non-LTE radiation transfer models, and by performing a standard Abel inversion on the residual radiance. SABER observations show that NO+(v) VER is significantly enhanced during magnetic storms in accordance with increased ionization of the neutral atmosphere by auroral electron precipitation, followed by vibrational excitation of NO+ (i.e., NO+(v)) from fast exothermic ion-neutral reactions, and prompt infrared emission at 4.3 m. Due to charge neutrality, the NO+(v) VER enhancements are highly correlated with electron density enhancements, as observed for example by Incoherent Scatter Radar (ISR). In order to characterize the response of the storm-time E-region from both SABER and ISR measurements, a Storm/Quiet ratio (SQR) quantity is defined as a function of altitude. For SABER, the SQR is the ratio of the storm-to-quiet NO+(v) VER. SQR is the storm-to-quiet ratio of electron densities for ISR. In this work, we compare SABER and ISR SQR values between 100 to 120 km. Results indicate good agreement between these measurements. SQR values are intended to be used as a correction factor to be included in an empirical storm-time correction to the International Reference Ionosphere model at E-region altitudes.

  3. Monoculture of leafcutter ant gardens.

    Directory of Open Access Journals (Sweden)

    Ulrich G Mueller

    2010-09-01

    Full Text Available Leafcutter ants depend on the cultivation of symbiotic Attamyces fungi for food, which are thought to be grown by the ants in single-strain, clonal monoculture throughout the hundreds to thousands of gardens within a leafcutter nest. Monoculture eliminates cultivar-cultivar competition that would select for competitive fungal traits that are detrimental to the ants, whereas polyculture of several fungi could increase nutritional diversity and disease resistance of genetically variable gardens.Using three experimental approaches, we assessed cultivar diversity within nests of Atta leafcutter ants, which are most likely among all fungus-growing ants to cultivate distinct cultivar genotypes per nest because of the nests' enormous sizes (up to 5000 gardens and extended lifespans (10-20 years. In Atta texana and in A. cephalotes, we resampled nests over a 5-year period to test for persistence of resident cultivar genotypes within each nest, and we tested for genetic differences between fungi from different nest sectors accessed through excavation. In A. texana, we also determined the number of Attamyces cells carried as a starter inoculum by a dispersing queens (minimally several thousand Attamyces cells, and we tested for genetic differences between Attamyces carried by sister queens dispersing from the same nest. Except for mutational variation arising during clonal Attamyces propagation, DNA fingerprinting revealed no evidence for fungal polyculture and no genotype turnover during the 5-year surveys.Atta leafcutter ants can achieve stable, fungal monoculture over many years. Mutational variation emerging within an Attamyces monoculture could provide genetic diversity for symbiont choice (gardening biases of the ants favoring specific mutational variants, an analog of artificial selection.

  4. The distribution and diversity of insular ants

    DEFF Research Database (Denmark)

    Roura-Pascual, Núria; Sanders, Nate; Hui, Cang

    2016-01-01

    Aim: To examine the relationship between island characteristics (area, distance to the nearest continent, climate and human population size) and ant species richness, as well as the factors underlying global geographical clustering of native and exotic ant composition on islands. Location: One...... hundred and two islands from 20 island groups around the world. Methods: We used spatial linear models that consider the spatial structure of islands to examine patterns of ant species richness. We also performed modularity analyses to identify clusters of islands hosting a similar suite of species...... and constructed conditional inference trees to assess the characteristics of islands that explain the formation of these island-ant groups. Results: Island area was the best predictor of ant species richness. However, distance to the nearest continent was an important predictor of native ant species richness...

  5. Antígona y la muerte

    OpenAIRE

    Pérez Alcolea, Simona Micaela

    2012-01-01

    La ponencia analiza la muerte de Antígona en la obra de Sófocles. Se propone que su suicidio es un acto consciente de voluntad preanunciado a lo largo de toda la obra y no una medida desesperada. Con ese fin se exploran las posibles motivaciones de Antígona para poner fin a su vida. En el análisis se proponen tres respuestas (no necesariamente excluyentes): -Antígona responde a la ética homérica. Está en lucha con Creón, y su suicidio es su golpe de gracia al poder del rey. -Antígona...

  6. From Ant Trails to Pedestrian Dynamics

    Directory of Open Access Journals (Sweden)

    Andreas Schadschneider

    2003-01-01

    Full Text Available This paper presents a model for the simulation of pedestrian dynamics inspired by the behaviour of ants in ant trails. Ants communicate by producing a pheromone that can be smelled by other ants. In this model, pedestrians produce a virtual pheromone that influences the motion of others. In this way all interactions are strictly local, and so even large crowds can be simulated very efficiently. Nevertheless, the model is able to reproduce the collective effects observed empirically, eg the formation of lanes in counterflow. As an application, we reproduce a surprising result found in experiments of evacuation from an aircraft.

  7. Ants defend aphids against lethal disease

    Science.gov (United States)

    Nielsen, Charlotte; Agrawal, Anurag A.; Hajek, Ann E.

    2010-01-01

    Social insects defend their own colonies and some species also protect their mutualist partners. In mutualisms with aphids, ants typically feed on honeydew produced by aphids and, in turn guard and shelter aphid colonies from insect natural enemies. Here we report that Formica podzolica ants tending milkweed aphids, Aphis asclepiadis, protect aphid colonies from lethal fungal infections caused by an obligate aphid pathogen, Pandora neoaphidis. In field experiments, bodies of fungal-killed aphids were quickly removed from ant-tended aphid colonies. Ant workers were also able to detect infective conidia on the cuticle of living aphids and responded by either removing or grooming these aphids. Our results extend the long-standing view of ants as mutualists and protectors of aphids by demonstrating focused sanitizing and quarantining behaviour that may lead to reduced disease transmission in aphid colonies. PMID:19923138

  8. Saberes docentes na prática do professor de música do Projeto SESC Cidadão

    OpenAIRE

    Araújo, José Magnaldo de Moura

    2016-01-01

    Este trabalho apresenta, discute e analisa como se constituem e de que forma se articulam os saberes docentes de um professor de música atuante no projeto social SESC Cidadão. Para alcançar tal objetivo foi realizada uma pesquisa que teve os seguintes objetivos específicos: verificar aspectos gerais acerca da formação cultural-profissional do professor atuante no SESC Cidadão; compreender de que forma os saberes adquiridos na formação “formal” do professor têm subsidiado sua ação pedagógica n...

  9. La memoria activa del saber pedagógico en la contemporaneidad

    Directory of Open Access Journals (Sweden)

    Vladimir ZAPATA VILLEGAS

    2013-11-01

    Full Text Available El artículo presenta el reencuentro crítico de tres proyectos paradigmáticos de la memoria activa del saber pedagógico: Comenio, proyecto de Didáctica; Herbart, proyecto de Pedagogía y Dewey, proyecto de Educación, con algunas pro- blemáticas teóricas de la actualidad acerca de la educación y la enseñanza. Los resultados de dicha interlocución se vinculan hoy a una memoria viva. Se utilizaron como herramientas metodológicas el cruce de diversos enfoques y técnicas tales como: la formación de los conceptos en la arqueología de los saberes, según los aportes de Foucault; la historia de conceptos practicada por Koselleck; y la relación del concepto con el presente, desde la epistemología. Los tres pedagogos fueron abordados desde dos perspectivas: 1 la relación de sus obras maestras con el momento histórico de su producción, y 2 la inscripción en un orden temporal diferente al de su producción.

  10. Collective search by ants in microgravity

    Directory of Open Access Journals (Sweden)

    Stefanie M. Countryman

    2015-03-01

    Full Text Available The problem of collective search is a tradeoff between searching thoroughly and covering as much area as possible. This tradeoff depends on the density of searchers. Solutions to the problem of collective search are currently of much interest in robotics and in the study of distributed algorithms, for example to design ways that without central control robots can use local information to perform search and rescue operations. Ant colonies operate without central control. Because they can perceive only local, mostly chemical and tactile cues, they must search collectively to find resources and to monitor the colony's environment. Examining how ants in diverse environments solve the problem of collective search can elucidate how evolution has led to diverse forms of collective behavior. An experiment on the International Space Station in January 2014 examined how ants (Tetramorium caespitum perform collective search in microgravity. In the ISS experiment, the ants explored a small arena in which a barrier was lowered to increase the area and thus lower ant density. In microgravity, relative to ground controls, ants explored the area less thoroughly and took more convoluted paths. It appears that the difficulty of holding on to the surface interfered with the ants’ ability to search collectively. Ants frequently lost contact with the surface, but showed a remarkable ability to regain contact with the surface.

  11. Pericarpial nectary-visiting ants do not provide fruit protection against pre-dispersal seed predators regardless of ant species composition and resource availability.

    Directory of Open Access Journals (Sweden)

    Priscila Andre Sanz-Veiga

    Full Text Available Extrafloral nectaries can occur in both vegetative and reproductive plant structures. In many Rubiaceae species in the Brazilian Cerrado, after corolla abscission, the floral nectary continues to secret nectar throughout fruit development originating post-floral pericarpial nectaries which commonly attract many ant species. The occurrence of such nectar secreting structures might be strategic for fruit protection against seed predators, as plants are expected to invest higher on more valuable and vulnerable parts. Here, we performed ant exclusion experiments to investigate whether the interaction with ants mediated by the pericarpial nectaries of Tocoyena formosa affects plant reproductive success by reducing the number of pre-dispersal seed predators. We also assessed whether ant protection was dependent on ant species composition and resource availability. Although most of the plants were visited by large and aggressive ant species, such as Ectatomma tuberculatum and species of the genus Camponotus, ants did not protect fruits against seed predators. Furthermore, the result of the interaction was neither related to ant species composition nor to the availability of resources. We suggest that these results may be related to the nature and behavior of the most important seed predators, like Hemicolpus abdominalis weevil which the exoskeleton toughness prevent it from being predated by most ant species. On the other hand, not explored factors, such as reward quality, local ant abundance, ant colony characteristics and/or the presence of alternative energetic sources could also account for variations in ant frequency, composition, and finally ant protective effects, highlighting the conditionality of facultative plant-ant mutualisms.

  12. The Biochemical Toxin Arsenal from Ant Venoms

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    Axel Touchard

    2016-01-01

    Full Text Available Ants (Formicidae represent a taxonomically diverse group of hymenopterans with over 13,000 extant species, the majority of which inject or spray secretions from a venom gland. The evolutionary success of ants is mostly due to their unique eusociality that has permitted them to develop complex collaborative strategies, partly involving their venom secretions, to defend their nest against predators, microbial pathogens, ant competitors, and to hunt prey. Activities of ant venom include paralytic, cytolytic, haemolytic, allergenic, pro-inflammatory, insecticidal, antimicrobial, and pain-producing pharmacologic activities, while non-toxic functions include roles in chemical communication involving trail and sex pheromones, deterrents, and aggregators. While these diverse activities in ant venoms have until now been largely understudied due to the small venom yield from ants, modern analytical and venomic techniques are beginning to reveal the diversity of toxin structure and function. As such, ant venoms are distinct from other venomous animals, not only rich in linear, dimeric and disulfide-bonded peptides and bioactive proteins, but also other volatile and non-volatile compounds such as alkaloids and hydrocarbons. The present review details the unique structures and pharmacologies of known ant venom proteinaceous and alkaloidal toxins and their potential as a source of novel bioinsecticides and therapeutic agents.

  13. The Biochemical Toxin Arsenal from Ant Venoms

    Science.gov (United States)

    Touchard, Axel; Aili, Samira R.; Fox, Eduardo Gonçalves Paterson; Escoubas, Pierre; Orivel, Jérôme; Nicholson, Graham M.; Dejean, Alain

    2016-01-01

    Ants (Formicidae) represent a taxonomically diverse group of hymenopterans with over 13,000 extant species, the majority of which inject or spray secretions from a venom gland. The evolutionary success of ants is mostly due to their unique eusociality that has permitted them to develop complex collaborative strategies, partly involving their venom secretions, to defend their nest against predators, microbial pathogens, ant competitors, and to hunt prey. Activities of ant venom include paralytic, cytolytic, haemolytic, allergenic, pro-inflammatory, insecticidal, antimicrobial, and pain-producing pharmacologic activities, while non-toxic functions include roles in chemical communication involving trail and sex pheromones, deterrents, and aggregators. While these diverse activities in ant venoms have until now been largely understudied due to the small venom yield from ants, modern analytical and venomic techniques are beginning to reveal the diversity of toxin structure and function. As such, ant venoms are distinct from other venomous animals, not only rich in linear, dimeric and disulfide-bonded peptides and bioactive proteins, but also other volatile and non-volatile compounds such as alkaloids and hydrocarbons. The present review details the unique structures and pharmacologies of known ant venom proteinaceous and alkaloidal toxins and their potential as a source of novel bioinsecticides and therapeutic agents. PMID:26805882

  14. Aphid egg protection by ants: a novel aspect of the mutualism between the tree-feeding aphid Stomaphis hirukawai and its attendant ant Lasius productus

    Science.gov (United States)

    Matsuura, Kenji; Yashiro, Toshihisa

    2006-10-01

    Aphids often form mutualistic associations with ants, in which the aphids provide the ants with honeydew and the ants defend the aphids from predators. In this paper, we report aphid egg protection by ants as a novel aspect of the deeply interdependent relationship between a tree-feeding aphid and its attendant ant. The ant Lasius productus harbours oviparous females, males, and eggs of the hinoki cypress-feeding aphid Stomaphis hirukawai in its nests in winter. We investigated the behaviour of ants kept with aphid eggs in petri dishes to examine whether the ants recognise the aphid eggs and tend them or only provide a refuge for the aphids. Workers carried almost all of the aphid eggs into the nest within 24 h. The ants indiscriminately tended aphid eggs collected from their own colonies and those from other ant colonies. The ants cleaned the eggs and piled them up in the nest, and egg tending by ants dramatically increased aphid egg survival rates. Starving the ants showed no significant effect on aphid egg survivorship. Without ants, aphid eggs were rapidly killed by fungi. These results suggested that grooming by the ants protected the aphid eggs, at least, against pathogenic fungi. This hygienic service afforded by the ants seems indispensable for egg survival of these aphids in an environment rich in potentially pathogenic microorganisms.

  15. Fire ants perpetually rebuild sinking towers

    Science.gov (United States)

    Phonekeo, Sulisay; Mlot, Nathan; Monaenkova, Daria; Hu, David L.; Tovey, Craig

    2017-07-01

    In the aftermath of a flood, fire ants, Solenopsis invicta, cluster into temporary encampments. The encampments can contain hundreds of thousands of ants and reach over 30 ants high. How do ants build such tall structures without being crushed? In this combined experimental and theoretical study, we investigate the shape and rate of construction of ant towers around a central support. The towers are bell shaped, consistent with towers of constant strength such as the Eiffel tower, where each element bears an equal load. However, unlike the Eiffel tower, the ant tower is built through a process of trial and error, whereby failed portions avalanche until the final shape emerges. High-speed and novel X-ray videography reveal that the tower constantly sinks and is rebuilt, reminiscent of large multicellular systems such as human skin. We combine the behavioural rules that produce rafts on water with measurements of adhesion and attachment strength to model the rate of growth of the tower. The model correctly predicts that the growth rate decreases as the support diameter increases. This work may inspire the design of synthetic swarms capable of building in vertical layers.

  16. Reorganização de saberes tradicionais em Los sorias, de Alberto Laiseca

    Directory of Open Access Journals (Sweden)

    Graciela Ravetti

    2014-09-01

    Full Text Available Resumo: Neste estudo, propõe-se uma consideração sobre a reformulação de saberes tradicionais em termos não metafísicos na obra do escritor argentino Alberto Laiseca, Los sorias (1998, construída a partir da convergência dos temas das religiões, da magia e da astrologia, lado a lado com outros saberes em face de (deshierarquização. Palavras chave: Literatura hispano-americana; literatura argenti­na; romance contemporâneo; ficção científica. Abstract: In this study, we propose a consideration on the reformulation of traditional knowledge in no metaphysical terms in the work of Argentine writer Alberto Laiseca, Los sorias (1998, constructed from the convergence of the themes of religion, magic and astrology alongside with other knowledge in the face of de-hierarchization. Keywords: Argentine literature; contemporary romance, science fiction, Spanish American literature.

  17. Ants Orase kultuurisõnum

    Index Scriptorium Estoniae

    2007-01-01

    26. jaanuaril toimub Tallinna Ülikooli Akadeemilises Raamatukogus seminar silmapaistvast Eesti teadlasest ja tõlkijast Ants Orasest. Esinevad kirjandusteadlased Tallinna Ülikoolist, Tartu Ülikoolist ja Eesti Kirjandusmuuseumist. Avaettekandeks on sõna Oklahoma Ülikooli professoril Vincent B. Leitchil, kes oli Ants Orase viimaseks juhendatavaks doktorandiks. Seminari korraldavad Tallinna Ülikool ja Eesti Kirjandusmuuseum. Vt ka Postimees, 26, jaan., lk. 18

  18. Ant-plant symbioses: Stalking the chuyachaqui.

    Science.gov (United States)

    Davidson, D W; McKey, D

    1993-09-01

    According to Quechua-speaking peoples, orchard-like stands ('Supay Chacras') of two Amazonian ant-plant species are cultivated by the devil, or 'Chuyachaqui'. These "devil gardens" offer extreme examples of specializations that have evolved repeatedly in ant-plant associations. Numerous investigations are beginning to disclose the identity of the Chuyachaqui - the forces behind evolutionary specialization in ant-plant symbioses. These developments have important implications for our understanding of modes of coevolution in symbiotic mutualism, remarkable convergent similarities in the form of ant-plant symbioses on different continents, and pronounced intercontinental differences in the diversity and taxonomic composition of associates. Copyright © 1993. Published by Elsevier Ltd.

  19. Stratospheric Temperature Trends Observed by TIMED/SABER

    Science.gov (United States)

    Xian, T.; Tan, R.

    2017-12-01

    Trends in the stratospheric temperature are studied based on the temperature profile observation from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER). The spatially trends are evaluated in different time scales ranging from decadal to monthly resolved. The results indicate a signature of BDC acceleration. There are strong warming trends (up to 9 K/decade) in the middle to upper stratosphere in the high latitude spring, summer, and autumn seasons, accompanied by strong cooling trends in the lower stratosphere. Besides, strong warming trends occurs through the whole stratosphere over the Southern Hemisphere, which confirms Antarctic ozone layer healing since 2000. In addition, the results demonstrate a significant warming trends in the middle of tropical stratosphere, which becomes strongest during June-July-August.

  20. La transposición didáctica como estatuto epistemológico fundante de los saberes académicos del profesor

    Directory of Open Access Journals (Sweden)

    Gerardo Andrés Perafán Echeverri

    2013-01-01

    Full Text Available En este trabajo se presentan, de manera parcial, resultados preliminares de la investigación sobre ''El conocimiento profesional docente: nuevas perspectivas epistemológicas y metodológicas'' desarrollada en el marco del programa de Doctorado Interinstitucional en Educación que ofrece la Universidad Pedagógica Nacional y que ha servido como campo conceptual y metodológico a diversos proyectos de investigación sobre el ''Conocimiento profesional docente específico, asociado a categorías particulares'' que adelantan estudiantes de doctorado y maestría bajo mi dirección. Partiendo de desarrollos previos, en los que se ha conceptualizado la noción de conocimiento profesional docente como sistema de ideas integradas, el autor propone una reconceptualización de la categoría saberes académicos del profesor, con el objeto de mostrar su independencia epistemológica de los saberes disciplinares. Por otra parte, dada esta independencia epistemológica de los saberes académicos del profesor respecto de los saberes de las disciplinas, se sugiere, desde la perspectiva de Chevallard, una reconceptualización de la noción de transposición didáctica, para ser entendida como el estatuto epistemológico y antropológico fundante de dichos saberes académicos. Lo anterior abre alternativas para pensar de otra manera el tema de los contenidos escolares, la formación docente y la profesión del educador.

  1. Saberes Híbridos: las Sugar Companys y la moderna plantación azucarera en Cuba

    Directory of Open Access Journals (Sweden)

    Fernández Prieto, Leida

    2015-06-01

    Full Text Available From the studies on the production and dissemination of knowledge, this paper explores the encounter and exchange between local and global practices and knowledge within the sugar plantation between the nineteenth and twentieth centuries, a process defined as “hybrid knowledge”. This article echoes the studies are in the region as a model of interregional also referred. Highlights some elements of Western Cuba sugar transferred to new plantations east through negotiation between local knowledge and practices and American knowledge, not without personal, imperial, scientific or businesstensions.Desde los estudios sobre la producción y difusión del conocimiento, este texto explora el encuentro e intercambio entre prácticas y saberes locales y globales dentro de la plantación azucarera entre los siglos XIX y XX, un proceso definido como “saberes híbridos”. Este artículo también se hace eco de los estudios que ven en la región como modelo de referencia interterritorial. En el texto se destacan algunos elementos del occidente azucarero cubano transferidos a las nuevas plantaciones del este a través de la negociación entre el conocimiento local y las prácticas y saberes estadounidenses, no exenta de tensiones personales, imperiales, científicas o empresariales.

  2. El Saber profesional de una maestra de infantil

    OpenAIRE

    Orozco Martínez, Susana

    2017-01-01

    Este artículo expone los saberes y práctica profesional de María, maestra de Educación Infantil 3 años de una escuela pública de Cataluña y a cargo 13 niñas y 11 niños. La recolección de datos posibilita profundizar en sus experiencias pedagógicas y en el proceso educativo que pone en marcha y que contribuyen en la creación y desarrollo de una relación educativa caracterizada por la atención a las necesidades individuales y a la singularidad de sus criaturas, desde un acompañamiento, acogimie...

  3. El sentir y el pensar, unidad fragmentada en la formación del ser humano y los retos de la educación ante esta dicotomía.

    Directory of Open Access Journals (Sweden)

    Amparo Vargas Quintero

    2014-02-01

    Full Text Available En este artículo planteo una discusión sobre los desafíos que debe enfrentar la educación ante los cambios que devienen con las exigencias del nuevo siglo, cambios que se evidencian en la vida cotidiana del hombre contemporáneo, los mismos que generan incertidumbre y propuestas pedagógicas capaces de responder integralmente. Es en este contexto en el que propongo una nueva perspectiva de la educaci6n artística como medio sensibilizador e integrador del currículo, que supere la tradición de una educación estética por mucho tiempo relegada y desintegrada de la vida académica en los proyectos educativos institucionales.

  4. La intuición en la psicología y en la psicoterapia

    OpenAIRE

    Lopera Echavarría, Juan Diego

    2009-01-01

    El trabajo del psicólogo, ya sea en investigación o en psicoterapia, está en gran medida fundamentado en la intuición, en ese saber sedimentado que se expresa como estado de ánimo, sensación difusa u ocurrencia. Se trata de un saber que precede la invención de conjeturas y las intervenciones del clínico. Pero la intuición, capacidad prístina del ser humano, debe formarse: los prejuicios la hacen errática. Se propone una depuración de prejuicios mediante al análisis de la intuición y del propi...

  5. Pedagogía y Saberes: 25 años

    Directory of Open Access Journals (Sweden)

    Alberto Martínez Boom

    2016-05-01

    Full Text Available Hace 25 años, un grupo de profesores de la Universidad Pedagógica Nacional, entre los cuales se encontraba la rectora de entonces Graciela Amaya de Ochoa, nos lanzamos a fundar la Revista Pedagogía y Saberes . El tiempo transcurrido desde su primera edición en 1990 parece suficiente para vislumbrar cómo aquello que nos propusimos arraigó, se sostuvo, mutó y se potenció a lo largo de sus 43 apariciones públicas. No se trata, por supuesto, de realizar un balance, sino de celebrar la conveniencia de quien puede mirar desde lejos, a grata distancia, y poder descifrar o incluso actualizar algunos argumentos que nos llevaron a insistir en la necesidad de fundar este proyecto cultural de gran envergadura para la Universidad y para el campo conceptual y estratégico de la pedagogía.  Una revista suele emerger en medio de exigencias, las nuestras trataban de plantear un debate conceptual, incluso estrictamente conceptual, sobre el lugar y el papel de la pedagogía y de los saberes al interior de las prácticas formativas de la Facultad de Educación de la Universidad Pedagógica Nacional. Debate profesoral más o menos restringido a criterios investigativos de quienes alimentaron y orientaron académicamente el horizonte de lo pedagógico a finales de la década de los ochenta e inicios de los noventa. La potencia de Pedagogía y Saberes  coincide con su nominativo, la Universidad ya tenía desde 1978 una publicación seriada dedicada a los asuntos de la educación, hacía falta consolidar otra producción y, con ella, a la comunidad académica capaz de poner en circulación los acumulados pedagógicos de la misma universidad. No sé hasta dónde esta insistencia se haya mantenido en la revista. No creo exagerar si llamo la atención sobre este viejo clamor que aún hoy resulta vital: necesitamos una inteligencia pedagógica, requerimos una élite pedagógica, podemos asumir la responsabilidad de una intelectualidad pedagógica capaz de

  6. Pollination and facultative ant-association in the African leopard ...

    African Journals Online (AJOL)

    The role of extra-floral nectar appears to be recruitment of foraging ants to tend the flowers resulting in a facultative ant-association between the orchid and gregarious ants. Four different ant species were found to forage on A. africana's inflorescences. Ant-tended inflorescences suffered significantly less damage by insects.

  7. ANT, tourism and situated globality

    DEFF Research Database (Denmark)

    Jóhannesson, Gunnar Thór; Ren, Carina Bregnholm; van der Duim, René

    2015-01-01

    viable descriptions of the collective condition of humans and more-than-humans in the Anthropocene. Also and moving past a merely descriptive approach, it discusses it as a useful tool to engage with the situated globalities which come into being through the socio-spatial coupling of tourism......In recent years Actor-network theory (ANT) has increasingly been felt in the field of tourism studies (Van der Duim, Ren, & Jóhannesson, 2012). An important implication of the meeting between ANT and tourism studies is the notion of tourism being described as a heterogeneous assemblage of what we...... are used to define as the separate spheres of nature and culture. This paper explores and relates the central tenets of ANT in tourism with regard to the concept of the Anthropocene. It presents the ANT approach as a flat and object-oriented ontology and methodology and explores its potentials to carve out...

  8. Recurrence analysis of ant activity patterns.

    Directory of Open Access Journals (Sweden)

    Felipe Marcel Neves

    Full Text Available In this study, we used recurrence quantification analysis (RQA and recurrence plots (RPs to compare the movement activity of individual workers of three ant species, as well as a gregarious beetle species. RQA and RPs quantify the number and duration of recurrences of a dynamical system, including a detailed quantification of signals that could be stochastic, deterministic, or both. First, we found substantial differences between the activity dynamics of beetles and ants, with the results suggesting that the beetles have quasi-periodic dynamics and the ants do not. Second, workers from different ant species varied with respect to their dynamics, presenting degrees of predictability as well as stochastic signals. Finally, differences were found among minor and major caste of the same (dimorphic ant species. Our results underscore the potential of RQA and RPs in the analysis of complex behavioral patterns, as well as in general inferences on animal behavior and other biological phenomena.

  9. Brincadeiras de rua, convivência urbana e ecologia dos saberes

    Directory of Open Access Journals (Sweden)

    ÁLAMO PIMENTEL

    2015-01-01

    Full Text Available Este artículo es el resultado de un estudio sobre la contribución de los juegos de la calle en la creación de procesos de convivencia urbana y en la diversificación de prácticas y saberes inherentes a las culturas populares que atraviesan lo cotidiano de las ciudades brasileñas. El texto se desarrolla a partir del análisis de documentos basados en los informes presentados por estudiantes de pedagogía de una institución de enseñanza superior del estado de Bahía. Los informes descriptivos analizados son el resultado de un proyecto didáctico de observación desde el punto de vista de los niños sobre la convivencia urbana. La base teórica del trabajo se inspira en las epistemologías del Sul según la propuesta de Boaventura de Sousa Santos (2008, sobre todo en lo referido a la comprensión de las ecologías de los saberes. A partir de los cuadros sinópticos presentados a lo largo del texto se expone una visión panorámica de los juegos de la calle en diferentes barrios de Salvador y sus implicaciones en la sustentabilidad de las culturas populares en los escenarios urbanos contemporáneos.

  10. Symbiotic mutualism with a community of opportunistic ants: protection, competition, and ant occupancy of the myrmecophyte Barteria nigritana (Passifloraceae)

    Science.gov (United States)

    Djiéto-Lordon, Champlain; Dejean, Alain; Gibernau, Marc; Hossaert-McKey, Martine; McKey, Doyle

    2004-10-01

    Barteria nigritana is a myrmecophyte tree of Lower Guinea coastal vegetation. Unlike the more specialised B. fistulosa, which harbours a single host-specific mutualistic ant, B. nigritana is associated with several opportunistic ants. Such symbiotic, yet opportunistic, ant-plant associations have been little studied. On 113 clumps of B. nigritana, we censused ant associates and herbivores and compared herbivory on plants occupied by different ants. In addition to these correlative data, protection conferred by different ant species was compared by herbivore-placement experiments. Identity of ant associate changed predictably over plant ontogeny. Pheidole megacephala was restricted to very small plants; saplings were occupied by either Oecophylla longinoda or Crematogaster sp., and the latter species was the sole occupant of larger trees. Damage by caterpillars of the nymphalid butterfly Acraea zetes accounted for much of the herbivory to leaves. Ant species differed in the protection provided to hosts. While P. megacephala provided no significant protection, plants occupied by O. longinoda and Crematogaster sp. suffered less damage than did unoccupied plants or those occupied by P. megacephala. Furthermore, O. longinoda provided more effective protection than did Crematogaster sp. Herbivore-placement experiments confirmed these results. Workers of O. longinoda killed or removed all larval instars of A. zetes. Crematogaster preyed on only the two first larval instars, and P. megacephala preyed mainly on eggs, only rarely attacking the two first larval instars. Opportunistic ants provided significant protection to this relatively unspecialised myrmecophyte. The usual associate of mature trees was not the species that provided most protection.

  11. Plant-ants use symbiotic fungi as a food source: new insight into the nutritional ecology of ant-plant interactions.

    Science.gov (United States)

    Blatrix, Rumsaïs; Djiéto-Lordon, Champlain; Mondolot, Laurence; La Fisca, Philippe; Voglmayr, Hermann; McKey, Doyle

    2012-10-07

    Usually studied as pairwise interactions, mutualisms often involve networks of interacting species. Numerous tropical arboreal ants are specialist inhabitants of myrmecophytes (plants bearing domatia, i.e. hollow structures specialized to host ants) and are thought to rely almost exclusively on resources derived from the host plant. Recent studies, following up on century-old reports, have shown that fungi of the ascomycete order Chaetothyriales live in symbiosis with plant-ants within domatia. We tested the hypothesis that ants use domatia-inhabiting fungi as food in three ant-plant symbioses: Petalomyrmex phylax/Leonardoxa africana, Tetraponera aethiops/Barteria fistulosa and Pseudomyrmex penetrator/Tachigali sp. Labelling domatia fungal patches in the field with either a fluorescent dye or (15)N showed that larvae ingested domatia fungi. Furthermore, when the natural fungal patch was replaced with a piece of a (15)N-labelled pure culture of either of two Chaetothyriales strains isolated from T. aethiops colonies, these fungi were also consumed. These two fungi often co-occur in the same ant colony. Interestingly, T. aethiops workers and larvae ingested preferentially one of the two strains. Our results add a new piece in the puzzle of the nutritional ecology of plant-ants.

  12. Assessment of the Quality of the Version 1.07 Temperature-Versus-Pressure Profiles of the Middle Atmosphere from TIMED/SABER

    Science.gov (United States)

    Remsberg, E. E.; Marshall, B. T.; Garcia-Comas, M.; Krueger, D.; Lingenfelser, G. S.; Martin-Torres, J.; Mlynczak, M. G.; Russell, J. M., III; Smith, A. K.; Zhao, Y.; hide

    2008-01-01

    The quality of the retrieved temperature-versus-pressure (or T(p)) profiles is described for the middle atmosphere for the publicly available Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) Version 1.07 (V1.07) data set. The primary sources of systematic error for the SABER results below about 70 km are (1) errors in the measured radiances, (2) biases in the forward model, and (3) uncertainties in the corrections for ozone and in the determination of the reference pressure for the retrieved profiles. Comparisons with other correlative data sets indicate that SABER T(p) is too high by 1-3 K in the lower stratosphere but then too low by 1 K near the stratopause and by 2 K in the middle mesosphere. There is little difference between the local thermodynamic equilibrium (LTE) algorithm results below about 70 km from V1.07 and V1.06, but there are substantial improvements/differences for the non-LTE results of V1.07 for the upper mesosphere and lower thermosphere (UMLT) region. In particular, the V1.07 algorithm uses monthly, diurnally averaged CO2 profiles versus latitude from the Whole Atmosphere Community Climate Model. This change has improved the consistency of the character of the tides in its kinetic temperature (T(sub k)). The T(sub k) profiles agree with UMLT values obtained from ground-based measurements of column-averaged OH and O2 emissions and of the Na lidar returns, at least within their mutual uncertainties. SABER T(sub k) values obtained near the mesopause with its daytime algorithm also agree well with the falling sphere climatology at high northern latitudes in summer. It is concluded that the SABER data set can be the basis for improved, diurnal-to-interannual-scale temperatures for the middle atmosphere and especially for its UMLT region.

  13. Seguimiento del paciente asmático: qué debe saber el farmacéutico comunitario

    Directory of Open Access Journals (Sweden)

    Plaza Zamora J

    2013-03-01

    Full Text Available El asma tiene una prevalencia de entre un 1 y un 18% dependiendo del país. En el proceso de atención al paciente, y a través de los síntomas que presenta (disnea, tos, sibilancias, opresión torácica, el farmacéutico comunitario puede hacer educación sanitaria para evitar los agentes causales del asma, sobre cómo usar el dispositivo de inhalación prescrito por el médico, explicar al paciente su medicación, cómo es su tratamiento para conocer mejor su enfermedad, qué signos y síntomas denotan una falta de control de la misma, qué métodos se pueden usar para monitorizar la evolución del asma, detectar una posible falta de efectividad del tratamiento por tener sintomatología a pesar de estar usando adecuadamente el dispositivo de inhalación, sospechar que exista algún medicamento causante del asma, repasar el resto de medicación que usa por si existieran interacciones que afectaran tanto a la efectividad como a la seguridad del tratamiento. Existe un importante infradiagnóstico del asma, un 57,5% según el ECRHS (siglas del inglés European Community Respiratory Health Survey. En la farmacia comunitaria se puede hacer cribado de la enfermedad con la ayuda de cuestionarios validados en niños y no validados en adultos. Mediante la presente revisión se pretende ofrecer al farmacéutico comunitario una herramienta práctica para su labor diaria de atención al paciente asmático.

  14. Maestros narrados en el cine. Una mirada entreabierta sobre la escuela, el saber y la formación

    Directory of Open Access Journals (Sweden)

    Érica Elexandra Areiza-Pérez

    2011-01-01

    Full Text Available El texto realiza una reflexión pedagógica a partir de tres producciones cinematográficas, a saber, Estrellas del cielo sobre la tierra, Rojo como el cielo y La sonrisa de Mona Lisa. El foco de atención de esta reflexión tiene relación con la figura del maestro y con el modo en que acoge o entorpece el proyecto humano de sus estudiantes. También se exploran algunas tensiones propias del escenario educativo y el lugar del saber en los procesos de formación.

  15. Teoría emergente en la construcción del saber pedagógico

    Directory of Open Access Journals (Sweden)

    Víctor Díaz Quero

    2004-05-01

    Full Text Available Explicar la construcción y reconstrucción del saber pedagógico de los docentes, desde las perspectivas de su formación y experiencia constituyó el propósito de este trabajo. La naturaleza de la investigación refiere la subjetividad como fuente de conocimiento y componente dimensional de lo humano. El método tilizado fue la etnometodología para evidenciar la acción del hombre y de los significados que da a su propia actividad. Se seleccionaron (6 seis docentes de manera intencional, quienes participaron como sujetos que construyen y reconstruyen sus prácticas como instancia de la construcción de su saber. Los datos fueron obtenidos a través de la entrevista semiestructurada, con base en tres criterios: (a grado de apertura. (b grado de socialización y (c área de interés. El análisis de esta información, permitió su organización en una red conceptual constituida por unidades de información, categorías, tipologías y conceptos integradores que logran configurar la teoría emergente a partir de la reflexión del docente, sobre y desde sus prácticas. Los resultados obtenidos revelan como uno de los principales hallazgos, la existencia en los docentes de un pensamiento disociado entre teoría y práctica y una teoría que define epistemológicamente al saber pedagógico como un proceso complejo y permanente.

  16. Influence of Solar-Geomagnetic Disturbances on SABER Measurements of 4.3 Micrometer Emission and the Retrieval of Kinetic Temperature and Carbon Dioxide

    Science.gov (United States)

    Mertens, Christopher J.; Winick, Jeremy R.; Picard, Richard H.; Evans, David S.; Lopez-Puertas, Manuel; Wintersteiner, Peter P.; Xu, Xiaojing; Mlynczak, Martin G.; Russell, James M., III

    2008-01-01

    Thermospheric infrared radiance at 4.3 micrometers is susceptible to the influence of solar-geomagnetic disturbances. Ionization processes followed by ion-neutral chemical reactions lead to vibrationally excited NO(+) (i.e., NO(+)(v)) and subsequent 4.3 micrometer emission in the ionospheric E-region. Large enhancements of nighttime 4.3 m emission were observed by the TIMED/SABER instrument during the April 2002 and October-November 2003 solar storms. Global measurements of infrared 4.3 micrometer emission provide an excellent proxy to observe the nighttime E-region response to auroral dosing and to conduct a detailed study of E-region ion-neutral chemistry and energy transfer mechanisms. Furthermore, we find that photoionization processes followed by ion-neutral reactions during quiescent, daytime conditions increase the NO(+) concentration enough to introduce biases in the TIMED/SABER operational processing of kinetic temperature and CO2 data, with the largest effect at summer solstice. In this paper, we discuss solar storm enhancements of 4.3 micrometer emission observed from SABER and assess the impact of NO(+)(v) 4.3 micrometer emission on quiescent, daytime retrievals of Tk/CO2 from the SABER instrument.

  17. Sobre a Formação Profissional dos Professores de Educação Física e as Teorias do Saber Docente On the professional education of physical education teachers and the teacher knowledge theories Sobre la formación profesional de los profesores de educación física y las teorías del saber docente

    Directory of Open Access Journals (Sweden)

    2006-11-01

    Full Text Available O objetivo do presente texto é discutir as teorias que enfocam os saberes e o trabalho dos professores na educação brasileira, particularmente no campo pedagógico da Educação Física. A idéia central é analisar o que essas teorias trazem sobre os saberes dos professores, buscando compreender suas possíveis contribuições e limitações. A partir da discussão com a literatura, o texto aborda as tradições teóricas presentes no campo de estudos sobre os saberes docentes e analisa o modo como a formação do professor de Educação Física é concebida no contexto de diferentes momentos do pensamento pedagógico brasileiro. Ao finalizar, o texto aponta as potencialidades e os riscos das investigações que se debruçam sobre os saberes docentes. PALAVRAS-CHAVE: educação física – formação de professores – saber docente The aim of this text is to discuss the theories that focus on teacher knowledge and teacher work in Brazilian education, especially in the pedagogical field of Physical Education. The main idea is to analyze what these theories bring to the issue of teacher knowledge in an attempt to understand their possible contributions and limitations. Starting from a discussion on the available literature, this text approaches the theoretical traditions which are present in the field of studies about teacher knowledge and analyzes the way by which teacher education for physical education teachers is conceived in the context of different moments in Brazilian pedagogical thinking. As a conclusion, this text points out the potentialities and the risks of the investigations on teacher knowledge. KEYWORDS: physical education – teacher education – teacher knowledge El objetivo del presente texto es discutir las teorías que enfocan los saberes y el trabajo de los profesores en la educación brasileña, particularmente en el campo pedagógico de la Educación Física. La idea central es analizar lo que esas teorías traen

  18. Pheromone disruption of Argentine ant trail integrity

    Science.gov (United States)

    Suckling, D.M.; Peck, R.W.; Manning, L.M.; Stringer, L.D.; Cappadonna, J.; El-Sayed, A. M.

    2008-01-01

    Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. ?? 2008 Springer Science+Business Media, LLC.

  19. Comparative Biomechanical Modeling of Metatherian and Placental Saber-Tooths: A Different Kind of Bite for an Extreme Pouched Predator.

    Science.gov (United States)

    Wroe, Stephen; Chamoli, Uphar; Parr, William C H; Clausen, Philip; Ridgely, Ryan; Witmer, Lawrence

    2013-01-01

    Questions surrounding the dramatic morphology of saber-tooths, and the presumably deadly purpose to which it was put, have long excited scholarly and popular attention. Among saber-toothed species, the iconic North American placental, Smilodon fatalis, and the bizarre South American sparassodont, Thylacosmilus atrox, represent extreme forms commonly forwarded as examples of convergent evolution. For S. fatalis, some consensus has been reached on the question of killing behaviour, with most researchers accepting the canine-shear bite hypothesis, wherein both head-depressing and jaw closing musculatures played a role in delivery of the fatal bite. However, whether, or to what degree, T. atrox may have applied a similar approach remains an open question. Here we apply a three-dimensional computational approach to examine convergence in mechanical performance between the two species. We find that, in many respects, the placental S. fatalis (a true felid) was more similar to the metatherian T. atrox than to a conical-toothed cat. In modeling of both saber-tooths we found that jaw-adductor-driven bite forces were low, but that simulations invoking neck musculature revealed less cranio-mandibular stress than in a conical-toothed cat. However, our study also revealed differences between the two saber-tooths likely reflected in the modus operandi of the kill. Jaw-adductor-driven bite forces were extremely weak in T. atrox, and its skull was even better-adapted to resist stress induced by head-depressors. Considered together with the fact that the center of the arc described by the canines was closer to the jaw-joint in Smilodon, our results are consistent with both jaw-closing and neck musculature playing a role in prey dispatch for the placental, as has been previously suggested. However, for T. atrox, we conclude that the jaw-adductors probably played no major part in the killing bite. We propose that the metatherian presents a more complete commitment to the already

  20. Congestion and communication in confined ant traffic

    Science.gov (United States)

    Gravish, Nick; Gold, Gregory; Zangwill, Andrew; Goodisman, Michael A. D.; Goldman, Daniel I.

    2014-03-01

    Many social animals move and communicate within confined spaces. In subterranean fire ants Solenopsis invicta, mobility within crowded nest tunnels is important for resource and information transport. Within confined tunnels, communication and traffic flow are at odds: trafficking ants communicate through tactile interactions while stopped, yet ants that stop to communicate impose physical obstacles on the traffic. We monitor the bi-directional flow of fire ant workers in laboratory tunnels of varied diameter D. The persistence time of communicating ant aggregations, τ, increases approximately linearly with the number of participating ants, n. The sensitivity of traffic flow increases as D decreases and diverges at a minimum diameter, Dc. A cellular automata model incorporating minimal traffic features--excluded volume and communication duration--reproduces features of the experiment. From the model we identify a competition between information transfer and the need to maintain jam-free traffic flow. We show that by balancing information transfer and traffic flow demands, an optimum group strategy exists which maximizes information throughput. We acknowledge funding from NSF PoLS #0957659 and #PHY-1205878.

  1. Selenium exposure results in reduced reproduction in an invasive ant species and altered competitive behavior for a native ant species

    International Nuclear Information System (INIS)

    De La Riva, Deborah G.; Trumble, John T.

    2016-01-01

    Competitive ability and numerical dominance are important factors contributing to the ability of invasive ant species to establish and expand their ranges in new habitats. However, few studies have investigated the impact of environmental contamination on competitive behavior in ants as a potential factor influencing dynamics between invasive and native ant species. Here we investigated the widespread contaminant selenium to investigate its potential influence on invasion by the exotic Argentine ant, Linepithema humile, through effects on reproduction and competitive behavior. For the fecundity experiment, treatments were provided to Argentine ant colonies via to sugar water solutions containing one of three concentrations of selenium (0, 5 and 10 μg Se mL −1 ) that fall within the range found in soil and plants growing in contaminated areas. Competition experiments included both the Argentine ant and the native Dorymyrmex bicolor to determine the impact of selenium exposure (0 or 15 μg Se mL −1 ) on exploitation- and interference-competition between ant species. The results of the fecundity experiment revealed that selenium negatively impacted queen survival and brood production of Argentine ants. Viability of the developing brood was also affected in that offspring reached adulthood only in colonies that were not given selenium, whereas those in treated colonies died in their larval stages. Selenium exposure did not alter direct competitive behaviors for either species, but selenium exposure contributed to an increased bait discovery time for D. bicolor. Our results suggest that environmental toxins may not only pose problems for native ant species, but may also serve as a potential obstacle for establishment among exotic species. - Highlights: • Argentine ant colonies exposed to selenium had reduced fecundity compared to unexposed colonies. • Viability of offspring was negatively impacted by selenium. • Queen survival was reduced in colonies

  2. Improved Ant Colony Clustering Algorithm and Its Performance Study

    Science.gov (United States)

    Gao, Wei

    2016-01-01

    Clustering analysis is used in many disciplines and applications; it is an important tool that descriptively identifies homogeneous groups of objects based on attribute values. The ant colony clustering algorithm is a swarm-intelligent method used for clustering problems that is inspired by the behavior of ant colonies that cluster their corpses and sort their larvae. A new abstraction ant colony clustering algorithm using a data combination mechanism is proposed to improve the computational efficiency and accuracy of the ant colony clustering algorithm. The abstraction ant colony clustering algorithm is used to cluster benchmark problems, and its performance is compared with the ant colony clustering algorithm and other methods used in existing literature. Based on similar computational difficulties and complexities, the results show that the abstraction ant colony clustering algorithm produces results that are not only more accurate but also more efficiently determined than the ant colony clustering algorithm and the other methods. Thus, the abstraction ant colony clustering algorithm can be used for efficient multivariate data clustering. PMID:26839533

  3. Current and potential ant impacts in the Pacific region

    Science.gov (United States)

    Loope, Lloyd L.; Krushelnycky, Paul D.

    2007-01-01

    Worldwide, ants are a powerful ecological force, and they appear to be dominant components of animal communities of many tropical and temperate ecosystems in terms of biomass and numbers of individuals (Bluthgen et al. 2000). For example, ants comprise up to 94% of arthropod individuals in fogging samples taken from diverse lowland tropical rainforest canopies, and 86% of the biomass (Davidson et al. 2003). The majority of these ant species and individuals obtain carbohydrates either from extrafloral nectaries or from sap-feeding Hemiptera that pass carbohydrate-rich “honeydew” to attending ants while concentrating nitrogen (N) from N-poor plant sap (Davidson et al. 2003). Honeydew and nectar represent key resources for arboreal ant species, although most ant species are at least partly carnivorous or scavengers (Bluthgen et al. 2004). In contrast to most of the terrestrial world, the biotas of many Pacific islands evolved without ants. Whereas endemic ant species are found in New Zealand (ca. 10 spp.), Tonga (ca. 10 spp.), and Samoa (ca. 12 spp.), other islands of Polynesia and parts of Micronesia likely lack native ants (Wilson and Taylor 1967, Wetterer 2002, Wetterer and Vargo 2003). About 20 Indo-Australian and western Pacific ant species range to the east and north of Samoa, but it is unclear how many of these were transported there by humans at some time (Wilson and Taylor 1967). Most of the remainder of the ant species currently found on Pacific islands are widespread species that fall in the category of “tramp species,” dispersed by recent human commerce and generally closely tied to human activity and urban areas (Wilson and Taylor 1967, McGlynn 1999). In Pacific island situations, some of these tramp ant species are able to thrive beyond areas of human activity. Relatively few ant species have been successful invaders of native communities on continents, and these include most of the species that pose the greatest problems for Pacific islands

  4. Oecophylla smaragdina food conversion efficiency: prospects for ant farming

    DEFF Research Database (Denmark)

    Offenberg, Hans Joachim

    2011-01-01

    can be combined with the use of the ants in biological control programmes in tropical plantations where pest insects are converted into ant biomass. To assess the cost-benefits of ant farming based on artificial feeding, food consumption and food conversion efficiency (ECI) of Oecophylla smaragdina......Oecophylla ants are sold at high prices on several commercial markets as a human delicacy, as pet food or as traditional medicine. Currently markets are supplied by ants collected from the wild; however, an increasing interest in ant farming exists as all harvest is easily sold and as ant farming...... selling prices these efficiencies led to rates of return from 1.52 to 4.56, respectively, if: (i) protein is supplied from commercial products; or (ii) alternatively supplied from free sources such as insects and kitchen waste. These results suggest that Oecophylla ant farming may become highly profitable...

  5. O saber e a tecnologia: mitos de um centro de tratamento intensivo

    Directory of Open Access Journals (Sweden)

    Bastos Marisa Antonini Ribeiro

    2002-01-01

    Full Text Available O presente artigo apresenta os resultados de um estudo etnográfico que teve como objetivo descrever a cultura dos enfermeiros de um centro de tratamento intensivo. Acreditando que o CTI é uma subcultura do hospital e que os enfermeiros intensivistas compartilham de símbolos e significados que foram desenvolvidos através das interações sociais no contexto da Terapia Intensiva, fui buscar no interacionismo simbólico e na descrição etnográfica a fundamentação teórico-metodológica para o presente estudo. Para compreender o processo de interiorização dos universos simbólicos no CTI, busquei descrever os sistemas temáticos de significados subjacentes às atividades dos enfermeiros intensivistas, através da observação participante, da entrevista etnográfica e da análise documental. Dentre os elementos culturais descritos, foi identificado o mito do saber e da tecnologia. Concluí que os mitos da tecnologia e do saber foram socialmente estabelecidos como estratégia de sobrevivência no cotidiano da terapia intensiva, repleto de riscos e incertezas.

  6. O saber e a tecnologia: mitos de um centro de tratamento intensivo

    Directory of Open Access Journals (Sweden)

    Marisa Antonini Ribeiro Bastos

    Full Text Available O presente artigo apresenta os resultados de um estudo etnográfico que teve como objetivo descrever a cultura dos enfermeiros de um centro de tratamento intensivo. Acreditando que o CTI é uma subcultura do hospital e que os enfermeiros intensivistas compartilham de símbolos e significados que foram desenvolvidos através das interações sociais no contexto da Terapia Intensiva, fui buscar no interacionismo simbólico e na descrição etnográfica a fundamentação teórico-metodológica para o presente estudo. Para compreender o processo de interiorização dos universos simbólicos no CTI, busquei descrever os sistemas temáticos de significados subjacentes às atividades dos enfermeiros intensivistas, através da observação participante, da entrevista etnográfica e da análise documental. Dentre os elementos culturais descritos, foi identificado o mito do saber e da tecnologia. Concluí que os mitos da tecnologia e do saber foram socialmente estabelecidos como estratégia de sobrevivência no cotidiano da terapia intensiva, repleto de riscos e incertezas.

  7. A cellular automata model for ant trails

    Indian Academy of Sciences (India)

    In this study, the unidirectional ant traffic flow with U-turn in an ant trail was investigated using one-dimensional cellular automata model. It is known that ants communicate with each other by dropping a chemical, called pheromone, on the substrate. Apart from the studies in the literature, it was considered in the model that ...

  8. Ant-Related Oviposition and Larval Performance in a Myrmecophilous Lycaenid

    Directory of Open Access Journals (Sweden)

    Matthew D. Trager

    2013-01-01

    Full Text Available We experimentally assessed ant-related oviposition and larval performance in the Miami blue butterfly (Cyclargus thomasi bethunebakeri. Ant tending had sex-dependent effects on most measures of larval growth: female larvae generally benefitted from increased tending frequency whereas male larvae were usually unaffected. The larger size of female larvae tended by ants resulted in a substantial predicted increase in lifetime egg production. Oviposition by adult females that were tended by C. floridanus ants as larvae was similar between host plants with or without ants. However, they laid relatively more eggs on plants with ants than did females raised without ants, which laid less than a third of their eggs on plants with ants present. In summary, we found conditional benefits for larvae tended by ants that were not accompanied by oviposition preference for plants with ants present, which is a reasonable result for a system in which ant presence at the time of oviposition is not a reliable indicator of future ant presence. More broadly, our results emphasize the importance of considering the consequences of variation in interspecific interactions, life history traits, and multiple measures of performance when evaluating the costs and benefits of mutualistic relationships.

  9. Ants as tools in sustainable agriculture

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2015-01-01

    1. With an expanding human population placing increasing pressure on the environment, agriculture needs sustainable production that can match conventional methods. Integrated pest management (IPM) is more sustainable, but not necessarily as efficient as conventional non-sustainable measures. 2...... in multiple crops. Their efficiency is comparable to chemical pesticides or higher, while at lower costs. They provide a rare example of documented efficient conservation biological control. 3. Weaver ants share beneficial traits with almost 13 000 other ant species and are unlikely to be unique...... of agricultural systems, this review emphasizes the potential of managing ants to achieve sustainable pest management solutions. The synthesis suggests future directions and may catalyse a research agenda on the utilization of ants, not only against arthropod pests, but also against weeds and plant diseases...

  10. SABERES DE CURA: UM ESTUDO SOBRE PAJELANÇA CABOCLA E MULHERES PAJÉS DA AMAZÔNIA

    Directory of Open Access Journals (Sweden)

    Maria Betânia Barbosa Albuquerque

    2012-05-01

    Full Text Available Este artigo analisa os saberes que perpassam as práticas de cura presentes na pajelança cabocla na Amazônia, em especial, as de mulheres pajés. Tem como objetivos descrever os saberes e as práticas de cura de três mulheres residentes na cidade de Soure, na ilha do Marajó, Pará, bem como refletir sobre o papel da mulher no contexto religioso e simbólico da pajelança. Metodologicamente, o artigo resulta de uma pesquisa de campo e bibliográfica, com abordagem qualitativa, constando da análise de entrevistas narrativas com três mulheres. Teoricamente, o estudo se baseou em autores como Galvão (1955, Maués (1990; 1999, Cavalcante (2008, Montal (1986, entre outros. A pajelança ou xamanismo na Amazônia é uma prática, em geral, permitida somente aos indivíduos do sexo masculino. Entretanto, no município de Soure não há restrição da mulher no exercíco da pajelança, exercício esse que é perpassado por um arsenal de saberes que envolve o conhecimento das plantas curativas, do ritmo das águas, dos ciclos da lua e da natureza

  11. SABERES E PRÁTICAS DOCENTES E ENSINO DE HISTÓRIA: TEMAS, CONCEITOS E REFERENCIAIS (1970-2014

    Directory of Open Access Journals (Sweden)

    Nadia Gaiofatto Gonçalves

    Full Text Available RESUMO: Este trabalho visa analisar a produção acadêmica sobre Saberes e Práticas Docentes relacionadas ao Ensino de História, presente em periódicos acadêmicos das áreas de Educação, Ensino e História, no período de 1970 a 2014, buscando-se evidenciar temas, conceitos e referenciais contemplados. Como principais referenciais, utilizam-se os conceitos de habitus e campo, de Pierre Bourdieu, e de representações e lutas de representações, de Roger Chartier. Como principais resultados, destacam-se a grande concentração da produção a partir do século XXI; a coincidência de aumento de artigos com a produção específica de saberes e práticas docentes no Brasil; a presença de conceitos relacionados a saberes e práticas docentes em significativa parte da produção, mas também artigos sem a explicitação de conceitos específicos a essa problematização; e a luta de representações que se desenha, com a entrada de trabalhos relacionados à perspectiva da Educação Histórica, para abordagem da temática no campo Ensino de História.

  12. Temperature Trends in the Polar Mesosphere between 2002-2007 using TIMED/SABER Data

    Science.gov (United States)

    Goldberg, Richard A.; Kutepov, Alexander A.; Pesnell, William Dean; Latteck, Ralph; Russell, James M.

    2008-01-01

    The TIMED Satellite was launched on December 7, 2001 to study the dynamics and energy of the mesosphere and lower thermosphere. The TIMED/SABER instrument is a limb scanning infrared radiometer designed to measure a large number of minor constituents as well as the temperature of the region. In this study, we have concentrated on the polar mesosphere, to investigate the temperature characteristics as a function of spatial and temporal considerations. We used the recently revised SABER dataset (1.07) that contains improved temperature retrievals in the Earth polar summer regions. Weekly averages are used to make comparisons between the winter and summer, as well as to study the variability in different quadrants of each hemisphere. For each year studied, the duration of polar summer based on temperature measurements compares favorably with the PMSE (Polar Mesospheric Summer Echoes) season measured by radar at the ALOMAR Observatory in Norway (69 N). The PMSE period should also define the summer period suitable for the occurrence of polar mesospheric clouds. The unusual short and relatively warm polar summer in the northern hemisphere

  13. Saberes ambientales lafkenche en escuelas de la costa de La Araucanía (Chile

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    Marcela Rojas-Maturana

    2015-01-01

    Full Text Available Este estudio es un acercamiento a la realidad de la transmisión oralde saberes y prácticas acerca del territorio, en familias lafkenche que viven asociadas a espaciosde humedales en el borde costero de La Araucanía (Chile. Para la recolección de datos aplicamosencuestas a niños y niñas, padres y madres, docentes, y asesores y asesoras culturales en cincoescuelas. Visualizamos que existen saberes territoriales que, sin embargo, no encuentran un espaciodónde manifestarse fuera del hogar. Concluimos que la sistematicidad en el acercamiento de losalumnos y alumnas a su cultura originaria, la permanencia en el tiempo de los asesores y asesorasculturales, el compromiso real de los profesores y profesoras no mapuches, y el respeto de estos haciala cultura, puede eventualmente lograr resultados satisfactorios en la preservación de la lengua y delas prácticas culturales en el territorio lafkenche.

  14. La lectura en el aula. Qué se hace, qué se debe hacer y qué se puede hacer

    OpenAIRE

    Pablo Lorente Muñoz

    2011-01-01

    Emilio Sánchez Miguel (Coord.). La lectura en el aula. Qué se hace, qué se debe hacer y qué se puede hacer. Graó, col. Crítica y Fundamentos, 27. Barcelona, 2010. 382 págs. ISBN: 978-84-7827-892-3

  15. ADAPTIVE ANT COLONY OPTIMIZATION BASED GRADIENT FOR EDGE DETECTION

    Directory of Open Access Journals (Sweden)

    Febri Liantoni

    2014-08-01

    Full Text Available Ant Colony Optimization (ACO is a nature-inspired optimization algorithm which is motivated by ants foraging behavior. Due to its favorable advantages, ACO has been widely used to solve several NP-hard problems, including edge detection. Since ACO initially distributes ants at random, it may cause imbalance ant distribution which later affects path discovery process. In this paper an adaptive ACO is proposed to optimize edge detection by adaptively distributing ant according to gradient analysis. Ants are adaptively distributed according to gradient ratio of each image regions. Region which has bigger gradient ratio, will have bigger number of ant distribution. Experiments are conducted using images from various datasets. Precision and recall are used to quantitatively evaluate performance of the proposed algorithm. Precision and recall of adaptive ACO reaches 76.98 % and 96.8 %. Whereas highest precision and recall for standard ACO are 69.74 % and 74.85 %. Experimental results show that the adaptive ACO outperforms standard ACO which randomly distributes ants.

  16. Fungal Adaptations to Mutualistic Life with Ants

    DEFF Research Database (Denmark)

    Kooij, Pepijn Wilhelmus

    Fungus-growing ants (Attini) feed off a fungus they cultivate in a mutualistic symbiosis in underground chambers by providing it substrate they collect outside the colony. The tribe of Attine ants ranges from small colonies of the paleo- and basal Attine species with a few hundred workers that fo...... that the fungus evolved some incredible adaptations to a mutualistic life with the ants....

  17. A construção do cuidado das parteiras tradicionais: um saber/fazer edificante La construcción del cuidado de las parteras tradicionales: un saber/hacer edificante The construction of care of the traditional midwives: an edificant knowledge/practice

    Directory of Open Access Journals (Sweden)

    Moema da Silva Borges

    2007-06-01

    Full Text Available Este artigo apresenta uma pesquisa realizada no Distrito Federal e região do Entorno do DF com o objetivo de identificar as representações sociais das parteiras tradicionais acerca do cuidado. Parte-se do pressuposto de que a base epistemológica da produção sobre o cuidado está ancorada em saberes científicos e também em outros saberes e práticas advindos do conhecimento do senso comum, dentre os quais se situa o trabalho das parteiras tradicionais. A partir dos dados colhidos acerca das características da prática, do nível de envolvimento com o fazer, da forma de construção do saber/fazer e das possibilidades de articulação da prática com outros saberes buscou-se identificar aspectos significativos da temática cuidado na visão das parteiras.Este artículo presenta una investigación llevado a través del Distrito federal y los alrededores del DF con el objetivo de identificar las representaciones sociales de las parteras tradicionales acerca del cuidado. El punto de partida es que la base epistemológica de la producción sobre el cuidado está anclada en el conocimiento científico y también en otros conocimientos y en las prácticas del conocimiento del senso común, entre los cuales está el trabajo de las parteras tradicionales. A partir de los datos recogidos sobre las características del trabajo práctico, el nivel de la implicación, la acción práctica, la forma de construcción del saber/hacer y las posibilidades de articular la acción práctica con otros saberes, se buscó identificar aspectos significativos de la temática el cuidado en la visión de las parteras tradicionales.This article presents a research carried through in Distrito Federal and surroundings with the objective to identify the social representations of the traditional midwives regarding the care. It's based on the starting point that the epistemological basis of the production about the care is anchored in scientific knowledge and also in

  18. Fast and flexible: argentine ants recruit from nearby trails.

    Science.gov (United States)

    Flanagan, Tatiana P; Pinter-Wollman, Noa M; Moses, Melanie E; Gordon, Deborah M

    2013-01-01

    Argentine ants (Linepithema humile) live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources.

  19. Republic of Kiribati Early Childhood Development : SABER and NSA-ECD Country Report 2014

    OpenAIRE

    World Bank Group

    2014-01-01

    This report presents an analysis of the Early Childhood Development (ECD) subsector, including programs and policies that affect young children in the Republic of Kiribati. This was a collaborative effort between UNICEF and the World Bank Group; it combines the World Bank Group’s Systems Approach for Better Education Results SABER-ECD framework, which includes analysis of early learningan...

  20. Hey! A Fire Ant Stung Me!

    Science.gov (United States)

    ... Videos for Educators Search English Español Hey! A Fire Ant Stung Me! KidsHealth / For Kids / Hey! A ... Me picó una roja o colorada! What's a Fire Ant? There are many different types of fire ...

  1. Fast and flexible: argentine ants recruit from nearby trails.

    Directory of Open Access Journals (Sweden)

    Tatiana P Flanagan

    Full Text Available Argentine ants (Linepithema humile live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources.

  2. El médico de la familia ante un suceso del ciclo vital: la entrada en la escuela

    Directory of Open Access Journals (Sweden)

    Dolores de la Cuesta Freijomil

    1997-04-01

    Full Text Available Se expresan las características generales de la etapa escolar, así como los requisitos de madurez que debe cumplir el niño para su ingreso en la escuela. Se destaca la función orientadora del médico de la familia ante este suceso, y la necesidad de utilizar adecuadamente la etapa preescolar como estadio de preparación de la etapa siguiente. Se proponen acciones para que el médico de la familia se desarrolle con vistas a incidir positivamente en la salud del escolar y la familia.The general characteristics of the school period, as well as the maturity requirements children should meet to enter school are expressed here. The orienting function of the family physician on this regard and the need to use the preschool period adequately as a preparatory step for the next one are also stressed. Some actions are proposed to be developed by the family physician in order to influence positively on the school children's health and family.

  3. Propuesta de infraestructura técnica de seguridad para un Equipo de Respuesta ante Incidentes de Seguridad (CSIRT

    Directory of Open Access Journals (Sweden)

    Heltton Emmanuel Ramírez Luna

    2015-02-01

    Full Text Available En este artículo se describe una propuesta creada para proteger la información y la infraestructura de un equipo de respuestas ante incidentes de seguridad (CSIRT, el cual es una organización dedicada a dar respuesta a incidencias de seguridad en tecnologías de la información. Un CSIRT está conformado por un grupo de expertos en seguridad de la información la cual provee de servicios como alertas y advertencias, tratamiento de incidentes, observatorio de tecnología, auditorías de seguridad, cómputo forense, entre otros. Por lo tanto, se hace uso de información sensible como datos de usuarios y de empresas que deberá tener fuertes métodos de seguridad. En este artículo se aborda una propuesta de los aspectos de seguridad que debe tener un CSIRT abarcando las áreas de Telecomunicaciones, Equipo hardware y Sistemas SIEM (Security Information and Event Management. Esta propuesta no toma en consideración la tipología en la que un CSIRT puede establecerse.

  4. De Florence Nightingale às perspectivas atuais sobre o cuidado de enfermagem: a evolução de um saber/fazer Desde Florence Nightingale a las perspectivas actuales sobre el cuidado en enfermería: la evolución del saber/hacer From Florence Nightingale to the current perspectives about nursing care: the evolution of a know-how

    Directory of Open Access Journals (Sweden)

    Fátima Helena do Espírito Santo

    2006-12-01

    Full Text Available O trabalho apresenta uma reflexão teórica sobre a evolução do cuidado de enfermagem a partir dos princípios nightingaleanos confrontados com as perspectivas atuais de alguns autores que vem abordando essa temática. Concluímos que as bases sólidas fincadas por Florence Nightingale estão permitindo à Enfermagem avançar em estudos que legitimam e fundamentam o cuidado enquanto essência do saber e fazer de enfermeiras e enfermeiros nos seus vários campos de atuação. Atualmente esses estudos apontam o cuidado como objeto de teorização em dimensões que aliam aspectos internos e externos à profissão, inserindo e explorando temas que antes eram velados, embora presentes no cotidiano da nossa prática, como o significado do corpo e suas formas de expressão na interação entre quem cuida e é cuidado.El trabajo presenta una reflexión teórica sobre la evolución del cuidado en el oficio de enfermeros a partir de los principios Nightingaleanos confrontados con las perspectivas actuales de algunos autores que vienen abordando esa temática. Concluimos que las bases sólidas lanzadas por Florence Nightingale están permitiendo al oficio de enfermeros avanzar en estudios que legitiman y fundamentan el cuidado en cuanto esencia del saber y hacer de las enfermeras y enfermeros en sus variados campos de actuación. Actualmente eses estudios indican el cuidado como objeto de teoría en dimensiones que alían aspectos internos y externos a la profesión, proponiendo y explorando temas que antes eran velados aunque presentes en el cotidiano de nuestra práctica como el significado del cuerpo y sus formas de expresión en la interacción entre quien cuida y quien es cuidado.The work presents a theoretical observation on the evolution of the nursing care from the Nightingalean principles faced to the current perspectives of some authors that approach this subject. We concluded that the solid base proposed by Florence Nightingale allow to

  5. La universidad: una escuela al servicio de la verdad

    Directory of Open Access Journals (Sweden)

    Josu AHEDO RUIZ

    2016-05-01

    Full Text Available El artículo trata de abordar, en diálogo con diversos autores, dos cuestiones que son claves para la Institución universitaria y constituyen, a su vez, la clave para un adecuado desarrollo social. De una parte, señalar uno de los riesgos por los que atraviesa la Universidad que no es otro que la dejadez en la búsqueda de la verdad; pero otro riesgo no menor que debe afrontar tiene que ver con el olvido de la verdadera misión de la Universidad: la formación humanística. Un desarrollo adecuado de estas dos cuestiones, no cabe duda, que ayudará a afianzar la Institución Universitaria, básica para un desarrollo armónico y sostenible de la sociedad, eliminando la incertidumbre en quienes deben de llevar a cabo esta tarea. El ideal de la búsqueda de la verdad es lo que caracteriza a la Universidad desde su inicio. Sin embargo, la sociedad actual que aboga por el éxito fáctico puede acarrear un olvido de aquella y su sustitución por otras cuestiones relacionadas con las competencias. Por tanto, conviene no convertir la Universidad en una mera capacitación profesional, soslayando también la formación humanística que no debe separarse de la búsqueda de la verdad. Conservar el ideal universitario originario implica entender la actividad docente como un servicio. Es por ello que el profesor debe abogar por la formación de cada estudiante, tratando de ayudarle a descubrir aquello que de verdad le importa como persona. La Universidad actual no debe olvidar que la tarea docente de transmisión del saber superior requiere que este sea incrementado también por quienes reciben esta formación académica. Por tanto, la tarea del docente debe ser integradora de todos los saberes, evitando la fragmentación que puede conllevar perder el horizonte de la búsqueda de la verdad.

  6. Cryptococcus neoformans carried by Odontomachus bauri ants

    Directory of Open Access Journals (Sweden)

    Mariana Santos de Jesus

    2012-06-01

    Full Text Available Cryptococcus neoformans is the most common causative agent of cryptococcosis worldwide. Although this fungus has been isolated from a variety of organic substrates, several studies suggest that hollow trees constitute an important natural niche for C. neoformans. A previously surveyed hollow of a living pink shower tree (Cassia grandis positive for C. neoformans in the city of Rio de Janeiro, Brazil, was chosen for further investigation. Odontomachus bauri ants (trap-jaw ants found inside the hollow were collected for evaluation as possible carriers of Cryptococcus spp. Two out of 10 ants were found to carry phenoloxidase-positive colonies identified as C. neoformans molecular types VNI and VNII. The ants may have acted as a mechanical vector of C. neoformans and possibly contributed to the dispersal of the fungi from one substrate to another. To the best of our knowledge, this is the first report on the association of C. neoformans with ants of the genus Odontomachus.

  7. [Ants as carriers of microorganisms in hospital environments].

    Science.gov (United States)

    Pereira, Rogério Dos Santos; Ueno, Mariko

    2008-01-01

    Concern exists regarding the real possibility of public health threats caused by pathogenic agents that are carried by urban ants. The present study had the objective of isolating and identifying the microorganisms that are associated with ants in hospital environments. One hundred and twenty-five ants of the same species were collected from different units of a university hospital. Each ant was collected using a swab soaked with physiological solution and was transferred to a tube containing brain heart infusion broth and incubated at 35 degrees C for 24 hours. From each tube, with growth, inoculations were made into specific culturing media, to isolate any microorganisms. The ants presented a high capacity for carrying microorganism groups: spore-producing Gram-positive bacilli 63.5%, Gram-negative bacilli 6.3%, Gram-positive cocci 23.1%, filamentous fungi 6.7% and yeast 0.5%. Thus, it can be inferred that ants may be one of the agents responsible for disseminating microorganisms in hospital environments.

  8. Cuando dialogan dos Antígonas: La tumba de Antígona de María Zambrano y Antígona furiosa de Griselda Gambaro

    Directory of Open Access Journals (Sweden)

    Rose Duroux

    2012-08-01

    Full Text Available Antígona ha sido un tópico por más de 2.000 años, participando de una historia que siempre puede ser reconocida. Tanto la Guerra Civil española como la dictadura argentina vieron surgir Antígonas en busca de justicia. A partir de los trabajos de María Zambrano y Griselda Gambaro, este artículo busca rehabilitar discursivamente estas versiones. Por un lado, la filósofa española nunca regresó del exilio iniciado en 1939 y defendió hasta el final los valores republicanos. Cuando asumió que su expatriación era irreversible, ingresó en un exilio profundo del cual Antígona revela lo esencial, pasando de la "privación" a la "revelación" tanto en un modo filosófico como en el poético, tanto en sus ensayos como en su única pieza teatral, La Tumba de Antígona [1967], una significativa metáfora de la guerra fratricida y del exilio. Por otro, Antígona furiosa [1986] de Gambaro, reescribe la tragedia de Sófocles cuando denuncia el terrorismo de estado argentino en una furiosa Antígona. Gambaro, hermana y madre de desaparecidos de la guerra sucia eleva su grito por justicia en nombre de la fraternidad humanaAntigone has been a topical figure for more than 2,000 years. She plays a part in a story that one can always identify. Spanish Civil War and Argentine dictatorship saw the birth of many Antigones seeking justice. Starting from the M. Zambrano and G. Gambaro's creations, this work rehabilitates the speech and the incarnations of the Iberian and Ibero-american Antigone. On the one hand, Spanish philosopher María Zambrano never came out of the exodus which began in 1939, and she defended the values of the Republic all the way. Once she acknowledged that expatriation was irreversible, she entered a profound exile of which Antigone reveals the essence, going from "deprivation" to "revelation" in a philosophical as well as a poetical manner, both in her essays and in her unique play, La Tumba de Antígona [1967], a striking metaphor

  9. Predaceous ants, beach replenishment, and nest placement by sea turtles.

    Science.gov (United States)

    Wetterer, James K; Wood, Lawrence D; Johnson, Chris; Krahe, Holly; Fitchett, Stephanie

    2007-10-01

    Ants known for attacking and killing hatchling birds and reptiles include the red imported fire ant (Solenopsis invicta Buren), tropical fire ant [Solenopsis geminata (Fabr.)], and little fire ant [Wasmannia auropunctata (Roger)]. We tested whether sea turtle nest placement influenced exposure to predaceous ants. In 2000 and 2001, we surveyed ants along a Florida beach where green turtles (Chelonia mydas L.), leatherbacks (Dermochelys coriacea Vandelli), and loggerheads (Caretta caretta L.) nest. Part of the beach was artificially replenished between our two surveys. As a result, mean beach width experienced by nesting turtles differed greatly between the two nesting seasons. We surveyed 1,548 sea turtle nests (2000: 909 nests; 2001: 639 nests) and found 22 ant species. S. invicta was by far the most common species (on 431 nests); S. geminata and W. auropunctata were uncommon (on 3 and 16 nests, respectively). In 2000, 62.5% of nests had ants present (35.9% with S. invicta), but in 2001, only 30.5% of the nests had ants present (16.4% with S. invicta). Turtle nests closer to dune vegetation had significantly greater exposure to ants. Differences in ant presence on turtle nests between years and among turtle species were closely related to differences in nest placement relative to dune vegetation. Beach replenishment significantly lowered exposure of nests to ants because on the wider beaches turtles nested farther from the dune vegetation. Selective pressures on nesting sea turtles are altered both by the presence of predaceous ants and the practice of beach replenishment.

  10. PRINCIPIOS EPISTEMOLÓGICOS Y AXIOLÓGICOS DEL SABER DOCENTE EN LA ENSEÑANZA DEL INGLÉS

    Directory of Open Access Journals (Sweden)

    Gustavo Córdoba González

    2010-01-01

    Full Text Available El presente artículo es resultado de una investigación etnográfica desarrolla con cuatro profesores de inglés que laboran en diferentes colegios rurales de la región de San Ramón, Alajuela, Costa Rica. El objetivo principal de este trabajo es analizar los principios epistemológicos y axiológicos del saber docente en la enseñanza del inglés. Los datos fueron obtenidos mediante entrevistas semiestructuradas y estructuradas aplicadas a los sujetos de investigación, así como mediante observaciones participantes y no participantes. Los resultados evidencian la configuración de cuatro dominios principales: el contenido-técnico, el metodológico, el legal-institucional y el económico. Estos dominios fungen como agentes reguladores y moldeadores de la práctica y del saber docente. La transcendencia de estos dominios del saber demuestra una preocupación fundamental sobre aspectos técnicos lingüísticos y metodológicos, conocimientos administrativos y legales en lo que respecta al valor y ejercicio de la enseñanza y aprendizaje del inglés. Finalmente, el valor y la importancia de enseñar y aprender inglés se percibe exclusivamente en términos económicos como un valor agregado de las habilidades y competencias que un individuo puede ofrecer en el mercado laboral.

  11. Studies on the environmental implications of ants (Hymenoptera ...

    African Journals Online (AJOL)

    A study of ants associated wh two synanthropcenvironments in Awka was carried out in 2008 using pitfall and bait traps. The study yelded a total of 561 ants wth 409 obtaned from the hemisynanthrophic environment while 192 ants were collected from the endophilic environment. The percentage occurrence, total dstribution ...

  12. Tracing the rise of ants - out of the ground.

    Directory of Open Access Journals (Sweden)

    Andrea Lucky

    Full Text Available The evolution of ants (Hymenoptera: Formicidae is increasingly well-understood due to recent phylogenetic analyses, along with estimates of divergence times and diversification rates. Yet, leading hypotheses regarding the ancestral habitat of ants conflict with new findings that early ant lineages are cryptic and subterranean. Where the ants evolved, in respect to habitat, and how habitat shifts took place over time have not been formally tested. Here, we reconstruct the habitat transitions of crown-group ants through time, focusing on where they nest and forage (in the canopy, litter, or soil. Based on ancestral character reconstructions, we show that in contrast to the current consensus based on verbal arguments that ants evolved in tropical leaf litter, the soil is supported as the ancestral stratum of all ants. We also find subsequent movements up into the litter and, in some cases, into the canopy. Given the global importance of ants, because of their diversity, ecological influence and status as the most successful eusocial lineage on Earth, understanding the early evolution of this lineage provides insight into the factors that made this group so successful today.

  13. Insecticide transfer efficiency and lethal load in Argentine ants

    Energy Technology Data Exchange (ETDEWEB)

    Hooper-Bui, L.M. [Department of Environmental Science, Louisiana State University, Baton Rouge, LA 70803 (United States); Department of Entomology, University of California, Riverside, CA 92521 (United States); Kwok, E.S.C. [Department of Cell Biology and Neuroscience, University of California, Riverside, CA 92521 (United States); Buchholz, B.A., E-mail: buchholz2@llnl.gov [Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Department of Environmental Toxicology, University of California, Davis, CA 95616 (United States); Rust, M.K. [Department of Entomology, University of California, Riverside, CA 92521 (United States); Eastmond, D.A. [Department of Cell Biology and Neuroscience, University of California, Riverside, CA 92521 (United States); Vogel, J.S. [Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States)

    2015-10-15

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of {sup 14}C-sucrose, {sup 14}C-hydramethylnon, and {sup 14}C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), but dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). The distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. Bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.

  14. Insecticide transfer efficiency and lethal load in Argentine ants

    International Nuclear Information System (INIS)

    Hooper-Bui, L.M.; Kwok, E.S.C.; Buchholz, B.A.; Rust, M.K.; Eastmond, D.A.; Vogel, J.S.

    2015-01-01

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of 14 C-sucrose, 14 C-hydramethylnon, and 14 C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), but dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). The distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. Bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.

  15. The Pied Piper: A Parasitic Beetle's Melodies Modulate Ant Behaviours.

    Directory of Open Access Journals (Sweden)

    Andrea Di Giulio

    Full Text Available Ants use various communication channels to regulate their social organisation. The main channel that drives almost all the ants' activities and behaviours is the chemical one, but it is long acknowledged that the acoustic channel also plays an important role. However, very little is known regarding exploitation of the acoustical channel by myrmecophile parasites to infiltrate the ant society. Among social parasites, the ant nest beetles (Paussus are obligate myrmecophiles able to move throughout the colony at will and prey on the ants, surprisingly never eliciting aggression from the colonies. It has been recently postulated that stridulatory organs in Paussus might be evolved as an acoustic mechanism to interact with ants. Here, we survey the role of acoustic signals employed in the Paussus beetle-Pheidole ant system. Ants parasitised by Paussus beetles produce caste-specific stridulations. We found that Paussus can "speak" three different "languages", each similar to sounds produced by different ant castes (workers, soldiers, queen. Playback experiments were used to test how host ants respond to the sounds emitted by Paussus. Our data suggest that, by mimicking the stridulations of the queen, Paussus is able to dupe the workers of its host and to be treated as royalty. This is the first report of acoustic mimicry in a beetle parasite of ants.

  16. Ant species confer different partner benefits on two neotropical myrmecophytes.

    Science.gov (United States)

    Frederickson, Megan E

    2005-04-01

    The dynamics of mutualistic interactions involving more than a single pair of species depend on the relative costs and benefits of interaction among alternative partners. The neotropical myrmecophytes Cordia nodosa and Duroia hirsuta associate with several species of obligately symbiotic ants. I compared the ant partners of Cordia and Duroia with respect to two benefits known to be important in ant-myrmecophyte interactions: protection against herbivores provided by ants, and protection against encroaching vegetation provided by ants. Azteca spp., Myrmelachista schumanni, and Allomerus octoarticulatus demerarae ants all provide the leaves of Cordia and Duroia some protection against herbivores. However, Azteca and Allomerus provide more protection than does Myrmelachista to the leaves of their host plants. Although Allomerus protects the leaves of its hosts, plants occupied by Allomerus suffer more attacks by herbivores to their stems than do plants occupied by other ants. Relative to Azteca or Allomerus, Myrmelachista ants provide better protection against encroaching vegetation, increasing canopy openness over their host plants. These differences in benefits among the ant partners of Cordia and Duroia are reflected in the effect of each ant species on host plant size, growth rate, and reproduction. The results of this study show how mutualistic ant partners can differ with respect to both the magnitude and type of benefits they provide to the same species of myrmecophytic host.

  17. Aportes para la educación inicial: saberes construidos por el Proyecto Pedagógico Educativo Comunitario

    Directory of Open Access Journals (Sweden)

    Nisme Yurany Pineda-Báez

    2015-02-01

    Full Text Available En este estudio nuestro objetivo fue evidenciar los saberes y prácticas pedagógicas construidas en los 20 años de implementación del Proyecto Pedagógico Educativo Comunitario -Ppec-del Instituto Colombiano de Bienestar Familiar -ICBF-con la primera infancia. Se trata de la sistematización de 78 entrevistas que realizamos, en las que participaron 181 personas. Las categorías que nuclearon el proceso fueron la reconstrucción histórica del Ppec, la concepción, la intencionalidad, los saberes y prácticas pedagógicas y la operacionalización de la propuesta. En la génesis del Ppec se evidencia una forma de construcción de la política en diálogo con las prácticas, alimentada por la reflexión institucional y la revisión crítica de las discusiones de la época en torno al desarrollo infantil y social. Los saberes y las prácticas pedagógicas construidas con la primera infancia se caracterizan por ser participativas, significativas, contextuadas y humanizantes, constituyendo un tejido que se nutre además de los recursos comunitarios, del entorno y del medio ambiente, para constituirse en un proyecto de transformación social.

  18. Life-Histories of Sub-Arctic Ants

    OpenAIRE

    Heinze, Jürgen

    1993-01-01

    Ant species belonging to seven genera occur in habitats near the tree line in the Northern Hemisphere. An analysis of colony founding strategies suggests that in addition to physiological cold resistance, behavioral and sociometric adaptations might be important for survival and propagation of ants in subarctic biomes.

  19. Cola Bora Bora, experiencias en torno al procomún. Entrevista con Ricardo Antón ColaBoraBora, experiences around the commons. Interview with Ricardo Antón

    Directory of Open Access Journals (Sweden)

    David Prieto Serrano

    2013-03-01

    Full Text Available Ricardo Antón es co-director de Amasté, oficina de ideas detrás de ColaBoraBora (CBB; un proyecto en torno al procomún, el código abierto, las dinámicas colaborativas y el emprendizaje social surgido del marco de oportunidad ofrecido por Eutokia, Centro de Innovación Social de Bilbao. En esta entrevista se describe tanto el propio proyecto como reflexiones generales generadas a lo largo del propio camino de CBB: respondiendo cuestiones como qué se entiende por procomún, sobre la posibilidad de generar una economía social, sobre los frenos culturales, institucionales y personales a la hora de emprender el proyecto o sobre la necesidad de articular teoría y práctica para construir un saber procomún.Ricardo Anton is co-director of Amasté, an office of ideas behind the project ColaBoraBora which focuses on the commons, open source, collaborative dynamics and social entrepreneurship emerged from the opportunity framework offered by Eutokia , a Centre of Social Innovation in Bilbao. In this interview, the author not only describes the project itself but also the general reflections generated along the road of CBB: answering questions such as what is meant by the commons, and questions about the possibility of generating a social economy, about cultural, institutional and personal obstacles when undertaking the project or about the need to link theory and practice to build a common knowledge.

  20. Edge detection in digital images using Ant Colony Optimization

    Directory of Open Access Journals (Sweden)

    Marjan Kuchaki Rafsanjani

    2015-11-01

    Full Text Available Ant Colony Optimization (ACO is an optimization algorithm inspired by the behavior of real ant colonies to approximate the solutions of difficult optimization problems. In this paper, ACO is introduced to tackle the image edge detection problem. The proposed approach is based on the distribution of ants on an image; ants try to find possible edges by using a state transition function. Experimental results show that the proposed method compared to standard edge detectors is less sensitive to Gaussian noise and gives finer details and thinner edges when compared to earlier ant-based approaches.

  1. Aprender a través de la escritura. los diarios de prácticas y el desarrollo de saberes experienciales

    Directory of Open Access Journals (Sweden)

    Ester Caparrós Martín

    2017-07-01

    Full Text Available En este artículo presentamos una experiencia de asesoramiento a estudiantes de las asignaturas de Practicum, en las titulaciones de Educación Social (Universidades de Málaga y Almería y Educación Infantil (Universidad de Valencia. El sentido con el que hemos pensado y conducido esta práctica de asesoramiento, descansa en nuestra concepción del oficio educativo como un oficio personal. Esto significa, necesariamente, revisar los conocimientos teóricos de los que habitualmente nos valemos en la formación inicial, tendiendo a promover el desarrollo de saberes experienciales. A su vez, este planteamiento se sostiene desde la necesidad de contemplar la educación como experiencia, de manera que la formación inicial debe poder aspirar a desarrollar en las y los estudiantes aquellas disposiciones necesarias para pensar sobre si mismos en relación con lo vivido desde una actitud pedagógica reflexiva. En el artículo exponemos el uso de los diarios de prácticas, centrándonos en las posibilidades epistemológicas y formativas de la escritura. Nos detenemos en la narración de la experiencia didáctica desarrollada, analizando los entresijos del acompañamiento que hemos prestado a los estudiantes. El artículo finaliza con una serie de hallazgos que, formulados como tensiones, expresan las dificultades a las que nuestros estudiantes se enfrentan en relación a la escritura, relativas a, entre otras cuestiones: la tendencia a realizar una escritura plana (con poca profundidad, la dificultad para aceptar la incertidumbre a la que se enfrentan, las prisas por zanjar las situaciones vividas, o el enorme problema profesional de pensarse en la relación con el otro.

  2. On the Possibility of Accelerating Positron on an Electron Wake at SABER

    International Nuclear Information System (INIS)

    Ischebeck, R.; Joshi, C.; Katsouleas, T.C.; Muggli, P.; Wang, X.

    2008-01-01

    A new approach for positron acceleration in non-linear plasma wakefields driven by electron beams is presented. Positrons can be produced by colliding an electron beam with a thin foil target embedded in the plasma. Integration of positron production and acceleration in one stage is realized by a single relativistic, intense electron beam. Simulations with the parameters of the proposed SABER facility [1] at SLAC suggest that this concept could be tested there

  3. Stealthy invaders: the biology of Cardiocondyla tramp ants

    DEFF Research Database (Denmark)

    Heinze, J.; Cremer, Sylvia; Eckl, N.

    2006-01-01

    Many invasive ant species, such as the Argentine ant or the red imported fire ant, have huge colonies with thousands of mass-foraging workers, which quickly monopolise resources and therefore represent a considerable threat to the native ant fauna. Cardiocondyla obscurior and several other specie...

  4. The AINTEGUMENTA genes, MdANT1 and MdANT2, are associated with the regulation of cell production during fruit growth in apple (Malus × domestica Borkh.).

    Science.gov (United States)

    Dash, Madhumita; Malladi, Anish

    2012-06-25

    Fruit growth in apple (Malus × domestica Borkh.) is mediated by cell production and expansion. Genes involved in regulating these processes and thereby fruit growth, are not well characterized. We hypothesized that the apple homolog(s) of AINTEGUMENTA (ANT), an APETALA2-repeat containing transcription factor, regulates cell production during fruit growth in apple. Two ANT genes, MdANT1 and MdANT2, were isolated from apple and their expression was studied during multiple stages of fruit development. MdANT1 and MdANT2 expression was high during early fruit growth coincident with the period of cell production, rapidly declined during exit from cell production, and remained low during the rest of fruit development. The effects of increase in carbohydrate availability during fruit growth were characterized. Increase in carbohydrate availability enhanced fruit growth largely through an increase in cell production. Expression of MdANT1 and MdANT2 increased sharply by up to around 5-fold in response to an increase in carbohydrate availability. Expression of the ANT genes was compared across two apple genotypes, 'Gala' and 'Golden Delicious Smoothee' (GS), which differ in the extent of fruit growth, largely due to differences in cell production. In comparison to 'Gala', the larger fruit-size genotype, GS, displayed higher levels and a longer duration of MdANT1 and MdANT2 expression. Expression of the ANTs and cell cycle genes in the fruit core and cortex tissues isolated using laser capture microdissection was studied. During early fruit growth, expression of the MdANTs was higher within the cortex, the tissue that constitutes the majority of the fruit. Additionally, MdANT1 and MdANT2 expression was positively correlated with that of A- and B-type CYCLINS, B-type CYCLIN-DEPENDENT-KINASES (CDKBs) and MdDEL1. Multiple lines of evidence from this study suggest that MdANT1 and MdANT2 regulate cell production during fruit growth in apple. ANTs may coordinate the expression of

  5. Current issues in the evolutionary ecology of ant-plant symbioses.

    Science.gov (United States)

    Mayer, Veronika E; Frederickson, Megan E; McKey, Doyle; Blatrix, Rumsaïs

    2014-05-01

    Ant-plant symbioses involve plants that provide hollow structures specialized for housing ants and often food to ants. In return, the inhabiting ants protect plants against herbivores and sometimes provide them with nutrients. Here, we review recent advances in ant-plant symbioses, focusing on three areas. First, the nutritional ecology of plant-ants, which is based not only on plant-derived food rewards, but also on inputs from other symbiotic partners, in particular fungi and possibly bacteria. Food and protection are the most important 'currencies' exchanged between partners and they drive the nature and evolution of the relationships. Secondly, studies of conflict and cooperation in ant-plant symbioses have contributed key insights into the evolution and maintenance of mutualism, particularly how partner-mediated feedbacks affect the specificity and stability of mutualisms. There is little evidence that mutualistic ants or plants are under selection to cheat, but the costs and benefits of ant-plant interactions do vary with environmental factors, making them vulnerable to natural or anthropogenic environmental change. Thus, thirdly, ant-plant symbioses should be considered good models for investigating the effects of global change on the outcome of mutualistic interactions. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  6. Disciplina, saber y existencia

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Ospina

    2004-10-01

    Full Text Available El presente trabajo aborda, de manera didáctica, la importante distinción entre disciplina y profesión y propone entender por disciplina la formación del carácter y la personalidad sin invalidar el significado genuino de disciplina académica o científica. Al presentar dos posturas clásicas frente al saber: la de Aristóteles y la de Comte, se muestran los límites de ésta última cuando pretende abarcar la vida misma con criterios de eficiencia y productividad, anulando el libre juego de la existencia que se regula por criterios muy distintos a la universalidad teórica y a la operatividad técnica. La disciplina, así entendida, no alude al mero estrechamiento de la mirada sobre el mundo o a pautas de acción fijas; se refiere, por el contrario, a la ampliación de los criterios de actuación que nos ayuden a decidir sobre lo mejor para la propia vida y la de los demás. Al aplicar estos elementos de reflexión a la educación contemporánea, se concluye en la necesidad de buscar la formación disciplinada de la persona que involucre necesariamente al menos el desarrollo de dos características formativas básicas: la autonomía y el espíritu crítico.

  7. Disciplina, saber y existencia

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Ospina H

    2004-01-01

    Full Text Available El presente trabajo aborda, de manera didáctica, la importante distinción entre disciplina y profesión y propone entender por disciplina la formación del carácter y la personalidad sin invalidar el significado genuino de disciplina académica o científica. Al presentar dos posturas clásicas frente al saber: la de Aristóteles y la de Comte, se muestran los límites de ésta última cuando pretende abarcar la vida misma con criterios de eficiencia y productividad, anulando el libre juego de la existencia que se regula por criterios muy distintos a la universalidad teórica y a la operatividad técnica. La disciplina, así entendida, no alude al mero estrechamiento de la mirada sobre el mundo o a pautas de acción fijas; se refiere, por el contrario, a la ampliación de los criterios de actuación que nos ayuden a decidir sobre lo mejor para la propia vida y la de los demás. Al aplicar estos elementos de reflexión a la educación contemporánea, se concluye en la necesidad de buscar la formación disciplinada de la persona que involucre necesariamente al menos el desarrollo de dos características formativas básicas: la autonomía y el espíritu crítico.

  8. Saber más sobre disfagia (en Lectura Fácil)

    OpenAIRE

    Pérez, Rosa Ana

    2016-01-01

    El objetivo de la guía es que las personas con discapacidad intelectual que tienen disfagia conozcan mejor su condición y así puedan adquirir hábitos más saludables. La disfagia, al entorpecer o impedir la ingestión de alimento, puede provocar atragantamientos, infecciones, deshidratación o desnutrición. La situación se puede agravar por el desconocimiento y la falta de diagnóstico. Sin embargo, con información y los hábitos adecuados, pueden evitarse esas consecuencias. ‘Saber más sobre disf...

  9. The use of weaver ants (Oecophylla spp.) in tropical agriculture

    DEFF Research Database (Denmark)

    Offenberg, Hans Joachim

    2011-01-01

    by the consumed pest insects, can be harvested and utilised for nutrition as they are tasty and high in proteins, vitamins and minerals. Thus, plantations may function as ant farms and in addition to plant production also hosts the production of edible animal protein. In this setup harmful pest insects are turned...... farming as a way forward to solve an increasing future demand for protein. Weaver ant farming may build on natural food collected by the ants or alternatively be boosted by feeding the ant colonies actively with protein and sugar. In both cases, when ant biocontrol is combined with ant farming......, the environmental cost of protein production may fall even lower than for other insects as the ants feed on pests that would otherwise reduce the plant yield and since the farming area is simultaneously in use for plant production. In this presentation I provide data showing (i) how the harvest of ants can...

  10. Toxic industrial deposit remediation by ant activity

    Science.gov (United States)

    Jilkova, Veronika; Frouz, Jan

    2016-04-01

    Toxic industrial deposits are often contaminated by heavy metals and the substrates have low pH values. In such systems, soil development is thus slowed down by high toxicity and acidic conditions which are unfavourable to soil fauna. Ants (Hymenoptera, Formicidae) are considered tolerant to heavy metal pollution and are known to increase organic matter content and microbial activity in their nests. Here, we focused on soil remediation caused by three ant species (Formica sanguinea, Lasius niger, and Tetramorium sp.) in an ore-washery sedimentation basin near Chvaletice (Czech Republic). Soil samples were taken from the centre of ant nests and from the nest surroundings (>3 m from nests). Samples were then analyzed for microbial activity and biomass and contents of organic matter and nutrients. As a result, ant species that most influenced soil properties was F. sanguinea as there were higher microbial activity and total nitrogen and ammonia contents in ant nests than in the surrounding soil. We expected such a result because F. sanguinea builds conspicuous large nests and is a carnivorous species that brings substantial amounts of nitrogen in insect prey to their nests. Effects of the other two ant species might be lower because of smaller nests and different feeding habits as they rely mainly on honeydew from aphids or on plant seeds that do not contain much nutrients.

  11. Heat-induced symmetry breaking in ant (Hymenoptera: Formicidae escape behavior.

    Directory of Open Access Journals (Sweden)

    Yuan-Kai Chung

    Full Text Available The collective egress of social insects is important in dangerous situations such as natural disasters or enemy attacks. Some studies have described the phenomenon of symmetry breaking in ants, with two exits induced by a repellent. However, whether symmetry breaking occurs under high temperature conditions, which are a common abiotic stress, remains unknown. In our study, we deposited a group of Polyrhachis dives ants on a heated platform and counted the number of escaping ants with two identical exits. We discovered that ants asymmetrically escaped through two exits when the temperature of the heated platform was >32.75°C. The degree of asymmetry increased linearly with the temperature of the platform. Furthermore, the higher the temperature of heated platform was, the more ants escaped from the heated platform. However, the number of escaping ants decreased for 3 min when the temperature was higher than the critical thermal limit (39.46°C, which is the threshold for ants to endure high temperature without a loss of performance. Moreover, the ants tended to form small groups to escape from the thermal stress. A preparatory formation of ant grouping was observed before they reached the exit, indicating that the ants actively clustered rather than accidentally gathered at the exits to escape. We suggest that a combination of individual and grouping ants may help to optimize the likelihood of survival during evacuation.

  12. Experiência e competência no ensino: pistas de reflexões sobre a natureza do saber-ensinar na perspectiva da ergonomia do trabalho docente

    Directory of Open Access Journals (Sweden)

    THERRIEN JACQUES

    2001-01-01

    Full Text Available O texto propõe-se a desenvolver uma reflexão sobre um campo de investigação emergente e necessário para a compreensão do significado da experiência no saber-ensinar: o trabalho docente segundo a perspectiva da ergonomia, inspirada na cognição situada. Contextualizando os novos contornos da política educacional brasileira no cenário das reformas educacionais, o estudo privilegia o debate sobre a formação docente e suas atuais tendências. A reflexão traz elementos conceituais e teórico-metodológicos destinados à investigação da natureza do saber-ensinar, focalizando o estudo da competência no ensino no contexto dos saberes na base da prática docente.

  13. SENSIBILIDAD DE LA RAZÓN DE MOROSIDAD Y LIQUIDEZ DEL SISTEMA BANCARIO NACIONAL ANTE CAMBIOS EN EL ENTORNO: UN ENFOQUE UTILIZANDO DATOS DE PANEL

    Directory of Open Access Journals (Sweden)

    Olivier Cruz Méndez

    2001-12-01

    Full Text Available El objetivo principal de este estudio es identificar algunas variables del entorno que afectan los indicadores financieros de morosidad y de liquidez en el sistema bancario costarricense, cuantificar su efecto y determinar el rezago con que dicho efecto se presenta ante cambios en algunas variables del entorno.Mediante la aplicación del enfoque de datos de panel, el estudio brinda los siguientes resultados: i en general, se determinó para los indicadores de morosidad crediticia y de liquidez que existe una reacción similar a nivel de sistema bancario ante cambios en las variables del entorno; no obstante, entre los bancos se presentan diferencias en su comportamiento particular, las que se asocian con aspectos de capacidad empresarial, políticas internas, eficiencia operativa, experiencia y tecnología, entre otros; iilas variables que afectan con mayor intensidad la morosidad son: la devaluación, la inflación, las nuevas colocaciones crediticias y el ritmo de la actividad económica local; iii por su parte, las variables que impactan el indicador de liquidez son: la emisión monetaria, las tasas de interés en colones, la tasa de subasta, la tasa de indiferencia y la morosidad de los bancos; iv además se efectuó una cuantificación porcentual sobre el impacto en ambos indicadores ante cambios en las variables relevantes, así como el rezago que mostró mayor significancia en cada una de las variables.Desde el punto de vista del Banco Central los resultados permiten identificar qué variables podrían generar problemas sistémicos en cada una de las áreas evaluadas, lo cual debe ser tomado en consideración dentro del Sistema de Indicadores de Alerta Temprana al que da seguimiento la División Económica.

  14. Ants Orasest ja Anne Lange monograafiast / Jüri Talvet

    Index Scriptorium Estoniae

    Talvet, Jüri, 1945-

    2005-01-01

    Arvustus: Oras, Ants. Luulekool. I, Apoloogia / koostajad Hando Runnel ja Jaak Rähesoo. Tartu : Ilmamaa, 2003 ; Oras, Ants. Luulekool II, Meistriklass. Tartu : Ilmamaa, 2004 ; Lange, Anne. Ants Oras : [kirjandusteadlane, -kriitik ja tõlkija (1900-1982)]. Tartu : Ilmamaa, 2004

  15. Ant tending influences soldier production in a social aphid.

    Science.gov (United States)

    Shingleton, A W; Foster, W A

    2000-09-22

    The aphid Pseudoregma sundanica (Van der Goot) (Homoptera: Aphididae) has two defence strategies. It is obligatorily tended by various species of ant and also produces sterile soldiers. We investigated how they allocate their investment in these two strategies. We measured the size, number of soldiers, number and species of tending ant, and number and species of predators in P. sundanica populations. We found that the level of ant tending correlated negatively with soldier investment in P. sundanica. The species of tending ant also influenced soldier investment. We excluded ants from aphid populations and recorded changes in population size and structure over four weeks. Ant exclusion led to population decline and extinction. At the same time, surviving populations showed a significant increase in soldier investment. The data demonstrate that social aphids can adjust their investment in soldiers in direct response to environmental change.

  16. Do herbivores eavesdrop on ant chemical communication to avoid predation?

    Directory of Open Access Journals (Sweden)

    David J Gonthier

    Full Text Available Strong effects of predator chemical cues on prey are common in aquatic and marine ecosystems, but are thought to be rare in terrestrial systems and specifically for arthropods. For ants, herbivores are hypothesized to eavesdrop on ant chemical communication and thereby avoid predation or confrontation. Here I tested the effect of ant chemical cues on herbivore choice and herbivory. Using Margaridisa sp. flea beetles and leaves from the host tree (Conostegia xalapensis, I performed paired-leaf choice feeding experiments. Coating leaves with crushed ant liquids (Azteca instabilis, exposing leaves to ant patrolling prior to choice tests (A. instabilis and Camponotus textor and comparing leaves from trees with and without A. instabilis nests resulted in more herbivores and herbivory on control (no ant-treatment relative to ant-treatment leaves. In contrast to A. instabilis and C. textor, leaves previously patrolled by Solenopsis geminata had no difference in beetle number and damage compared to control leaves. Altering the time A. instabilis patrolled treatment leaves prior to choice tests (0-, 5-, 30-, 90-, 180-min. revealed treatment effects were only statistically significant after 90- and 180-min. of prior leaf exposure. This study suggests, for two ecologically important and taxonomically diverse genera (Azteca and Camponotus, ant chemical cues have important effects on herbivores and that these effects may be widespread across the ant family. It suggests that the effect of chemical cues on herbivores may only appear after substantial previous ant activity has occurred on plant tissues. Furthermore, it supports the hypothesis that herbivores use ant chemical communication to avoid predation or confrontation with ants.

  17. Consuming fire ants reduces northern bobwhite survival and weight gain

    Science.gov (United States)

    Myers, P.E.; Allen, Craig R.; Birge, Hannah E.

    2014-01-01

    Northern bobwhite quail, Colinus virginianus (L.) (Galliformes: Odontophoridae), population declines are well documented, but pinpointing the reasons for these decreases has proven elusive. Bobwhite population declines are attributed primarily to loss of habitat and land use changes. This, however, does not entirely explain population declines in areas intensively managed for bobwhites. Although previous research demonstrates the negative impact of red imported fire ant (Solenopsis invicta Buren) (Hymenoptera: Formicidae) on northern bobwhites, the mechanisms underlying this effect are largely unknown. To meet the protein demands of early growth and development, bobwhite chicks predominantly consume small insects, of which ants are a substantial proportion. Fire ants alter ant community dynamics by often reducing native ant diversity and abundance while concurrently increasing the abundance of individuals. Fire ants have negative effects on chicks, but they are also a large potential protein source, making it difficult to disentangle their net effect on bobwhite chicks. To help investigate these effects, we conducted a laboratory experiment to understand (1) whether or not bobwhites consume fire ants, and (2) how the benefits of this consumption compare to the deleterious impacts of bobwhite chick exposure to fire ants. Sixty bobwhite chicks were separated into two groups of 30; one group was provided with starter feed only and the second group was provided with feed and fire ants. Bobwhite chicks were observed feeding on fire ants. Chicks that fed on fire ants had reduced survival and weight gain. Our results show that, while fire ants increase potential food sources for northern bobwhite, their net effect on bobwhite chicks is deleterious. This information will help inform land managers and commercial bobwhite rearing operations.

  18. Extended phenotype: nematodes turn ants into bird-dispersed fruits

    DEFF Research Database (Denmark)

    Hughes, D P; Kronauer, D J C; Boomsma, J J

    2008-01-01

    A recent study has discovered a novel extended phenotype of a nematode which alters its ant host to resemble ripe fruit. The infected ants are in turn eaten by frugivorous birds that disperse the nematode's eggs.......A recent study has discovered a novel extended phenotype of a nematode which alters its ant host to resemble ripe fruit. The infected ants are in turn eaten by frugivorous birds that disperse the nematode's eggs....

  19. Biblioteca: espaço de saber e de poder

    Directory of Open Access Journals (Sweden)

    Keila Matida de Melo Costa

    2009-03-01

    Full Text Available Este artigo tem como objetivo apresentar um pouco da trajetória investigativade Michel Foucault na tentativa de compreender o funcionamento do poder,o modo como ele opera no espaço de uma biblioteca. O projeto Panóptico deJeremy Bentham contribui para esse entendimento. Estudo bibliográfico, análisede campo, leitura de documentos e trabalhos sobre a Biblioteca do Cefet/GOdelineiam a efetivação deste percurso. Saber, poder, controle, individualização,normalização, entre outras problematizações que caracterizam aspectos dasociedade moderna, são identificadas na constituição do espaço de leituracitado.

  20. A Dedicated Z-Stent for Acquired Saber-Sheath Tracheobronchomalacia

    International Nuclear Information System (INIS)

    Kishi, Kazushi; Fujimoto, Hisashi Kobayashi; Sonomura, Tetsuo; Uetani, Kosaku; Nishida, Norifumi; Ohata, Masahiro; Sato, Morio; Yamada, Ryusaku

    1997-01-01

    The tracheobronchial lumen has a continuous horseshoe arch morphology. We formed Z-stents accordingly to support the weakened cartilagenous portions. With this type of stent we treated a patient with acquired saber-sheath type tracheobronchomalacia (TBM), Rayl's type II, Johnson's grade III, whose condition was aggravated even under positive end expiratory pressure (PEEP) therapy. The patient improved gradually. No immediate complication was observed. Bronchofiberscopic examination revealed that the tracheobronchial arcade was closely strut-braced and showed no expiratory collapse. Six months later, when the patient was intubated due to asthmatic attacks, tissue ingrowth through the stent was found and removed. There was no recurrence of TBM. The patient died 2 years later of pneumoconiosis

  1. Os mercados, os seus saberes e as suas incertezas

    Directory of Open Access Journals (Sweden)

    João Caraça

    2012-10-01

    Full Text Available A globalização, tal qual a conhecemos, não resolve os problemas, nem equaciona as questões, do viver em conjunto sobre a Terra. No contexto actual, a luta pela democracia assume, assim, três vectores essenciais: a reinvenção do poder emancipador do conhecimento, com mais e melhores ciências, ciências sociais e outros saberes argumentativos; a reintrodução da escola como o local privilegiado da aprendizagem para a cidadania plena; a instalação e defesa de uma sociedade do reconhecimento, em que a valorização do outro como interlocutor corresponda ao pulsar planetário da nossa espécie.

  2. SABER (TIMED) and MLS (UARS) Temperature Observations of Mesospheric and Stratospheric QBO and Related Tidal Variations

    Science.gov (United States)

    Huang, Frank T.; Mayr, Hans G.; Reber, Carl A.; Russell, James; Mlynczak, Marty; Mengel, John

    2006-01-01

    More than three years of temperature observations from the SABER (TIMED) and MLS WARS) instruments are analyzed to study the annual and inter-annual variations extending from the stratosphere into the upper mesosphere. The SABER measurements provide data from a wide altitude range (15 to 95 km) for the years 2002 to 2004, while the MLS data were taken in the 16 to 55 km altitude range a decade earlier. Because of the sampling properties of SABER and MLS, the variations with local solar time must be accounted for when estimating the zonal mean variations. An algorithm is thus applied that delineates with Fourier analysis the year-long variations of the migrating tides and zonal mean component. The amplitude of the diurnal tide near the equator shows a strong semiannual periodicity with maxima near equinox, which vary from year to year to indicate the influence from the Quasi-biennial Oscillation (QBO) in the zonal circulation. The zonal mean QBO temperature variations are analyzed over a range of latitudes and altitudes, and the results are presented for latitudes from 48"s to 48"N. New results are obtained for the QBO, especially in the upper stratosphere and mesosphere, and at mid-latitudes. At Equatorial latitudes, the QBO amplitudes show local peaks, albeit small, that occur at different altitudes. From about 20 to 40 km, and within about 15" of the Equator, the amplitudes can approach 3S K for the stratospheric QBO or SQBO. For the mesospheric QBO or MQBO, we find peaks near 70 km, with temperature amplitudes reaching 3.5"K, and near 85 km, the amplitudes approach 2.5OK. Morphologically, the amplitude and phase variations derived from the SABER and MLS measurements are in qualitative agreement. The QBO amplitudes tend to peak at the Equator but then increase again pole-ward of about 15" to 20'. The phase progression with altitude varies more gradually at the Equator than at mid-latitudes. A comparison of the observations with results from the Numerical Spectral

  3. Fungal enzymes in the attine ant symbiosis

    DEFF Research Database (Denmark)

    de Fine Licht, Henrik Hjarvard; Schiøtt, Morten; Boomsma, Jacobus Jan

    the more basal attine genera use substrates such as flowers, plant debris, small twigs, insect feces and insect carcasses. This diverse array of fungal substrates across the attine lineage implies that the symbiotic fungus needs different enzymes to break down the plant material that the ants provide...... or different efficiencies of enzyme function. Fungal enzymes that degrade plant cell walls may have functionally co-evolved with the ants in this scenario. We explore this hypothesis with direct measurements of enzyme activity in fungus gardens in 12 species across 8 genera spanning the entire phylogeny...... and diversity of life-styles within the attine clade. We find significant differences in enzyme activity between different genera and life-styles of the ants. How these findings relate to attine ant coevolution and crop optimization are discussed....

  4. The invasive ant, Solenopsis invicta, reduces herpetofauna richness and abundance

    Science.gov (United States)

    Allen, Craig R.; Birge, Hannah E.; Slater, J.; Wiggers, E.

    2017-01-01

    Amphibians and reptiles are declining globally. One potential cause of this decline includes impacts resulting from co-occurrence with non-native red imported fire ant, Solenopsis invicta. Although a growing body of anecdotal and observational evidence from laboratory experiments supports this hypothesis, there remains a lack of field scale manipulations testing the effect of fire ants on reptile and amphibian communities. We addressed this gap by measuring reptile and amphibian (“herpetofauna”) community response to successful fire ant reductions over the course of 2 years following hydramethylnon application to five 100–200 ha plots in southeastern coastal South Carolina. By assessing changes in relative abundance and species richness of herpetofauna in response to fire ant reductions, we were able to assess whether some species were particularly vulnerable to fire ant presence, and whether this sensitivity manifested at the community level. We found that herpetofauna abundance and species richness responded positively to fire ant reductions. Our results document that even moderate populations of red imported fire ants decrease both the abundance and diversity of herpetofauna. Given global herpetofauna population declines and continued spread of fire ants, there is urgency to understand the impacts of fire ants beyond anecdotal and singles species studies. Our results provides the first community level investigation addressing these dynamics, by manipulating fire ant abundance to reveal a response in herpetofauna species abundance and richness.

  5. Red imported fire ant impacts on upland arthropods in Southern Mississippi

    Science.gov (United States)

    Epperson, D.M.; Allen, Craig R.

    2010-01-01

    Red imported fire ants (Solenopsis invicta) have negative impacts on a broad array of invertebrate species. We investigated the impacts of fire ants on the upland arthropod community on 20???40 ha study sites in southern Mississippi. Study sites were sampled from 19972000 before, during, and after fire ant bait treatments to reduce fire ant populations. Fire ant abundance was assessed with bait transects on all sites, and fire ant population indices were estimated on a subset of study sites. Species richness and diversity of other ant species was also assessed from bait transects. Insect biomass and diversity was determined from light trap samples. Following treatments, fire ant abundance and population indices were significantly reduced, and ant species diversity and richness were greater on treated sites. Arthropod biomass, species diversity and species richness estimated from light trap samples were negatively correlated with fire ant abundance, but there were no observable treatment effects. Solenopsis invicta has the potential to negatively impact native arthropod communities resulting in a potential loss of both species and function.

  6. Host ant independent oviposition in the parasitic butterfly Maculinea alcon

    DEFF Research Database (Denmark)

    Fürst, Matthias A; Nash, David Richard

    2010-01-01

    to host-ant nests and non-host-ant nests, and the number and position of eggs attached were assessed. Our results show no evidence for host-ant-based oviposition in M. alcon, but support an oviposition strategy based on plant characteristics. This suggests that careful management of host-ant distribution......Parasitic Maculinea alcon butterflies can only develop in nests of a subset of available Myrmica ant species, so female butterflies have been hypothesized to preferentially lay eggs on plants close to colonies of the correct host ants. Previous correlational investigations of host......-ant-dependent oviposition in this and other Maculinea species have, however, shown equivocal results, leading to a long-term controversy over support for this hypothesis. We therefore conducted a controlled field experiment to study the egg-laying behaviour of M. alcon. Matched potted Gentiana plants were set out close...

  7. What do myrmecophagous geckos eat when ants are not available ...

    African Journals Online (AJOL)

    Like other Pristurus species, P. samhaensis on Samha and P. sokotranus on Socotra were highly myrmecophagous (76.7% and 38.6% ants, respectively). However, ants were absent from the diet of P. samhaensis on Darsa. In contrast to the rich native ant fauna of the other islands, only one ant species was reported for ...

  8. Signals can trump rewards in attracting seed-dispersing ants.

    Directory of Open Access Journals (Sweden)

    Kyle M Turner

    Full Text Available Both rewards and signals are important in mutualisms. In myrmecochory, or seed dispersal by ants, the benefits to plants are relatively well studied, but less is known about why ants pick up and move seeds. We examined seed dispersal by the ant Aphaenogaster rudis of four co-occurring species of plants, and tested whether morphology, chemical signaling, or the nutritional quality of fatty seed appendages called elaiosomes influenced dispersal rates. In removal trials, ants quickly collected diaspores (seeds plus elaiosomes of Asarum canadense, Trillium grandiflorum, and Sanguinaria canadensis, but largely neglected those of T. erectum. This discrepancy was not explained by differences in the bulk cost-benefit ratio, as assessed by the ratio of seed to elaiosome mass. We also provisioned colonies with diaspores from one of these four plant species or no diaspores as a control. Colonies performed best when fed S. canadensis diaspores, worst when fed T. grandiflorum, and intermediately when fed A. canadense, T. erectum, or no diaspores. Thus, the nutritional rewards in elaiosomes affected colony performance, but did not completely predict seed removal. Instead, high levels of oleic acid in T. grandiflorum elaiosomes may explain why ants disperse these diaspores even though they reduce ant colony performance. We show for the first time that different elaiosome-bearing plants provide rewards of different quality to ant colonies, but also that ants appear unable to accurately assess reward quality when encountering seeds. Instead, we suggest that signals can trump rewards as attractants of ants to seeds.

  9. Psicopatología psicoanalítica: un saber en la encrucijada

    Directory of Open Access Journals (Sweden)

    Miguel Angel Sierra Rubio

    2013-03-01

    Full Text Available Con el objetivo de esclarecer la condición epistémica de la psicopatología psicoanalítica en el marco del saber freudiano, se analizan cuestionamientos previos sobre el campo psicopatológico y sus posibles modalidades relacionales con el psicoanálisis, la psicología clínica y la psiquiatría. Los resultados destacan la originalidad de la estrategia de Freud que, bajo el nombre del psicoanálisis, cobija un discurso racional sobre la experiencia del malestar subjetivo.

  10. La Botánica en el marco de las ciencias naturales: Diversas miradas desde el saber pedagógico pág: 35-50

    Directory of Open Access Journals (Sweden)

    Deysi Serrato Rodríguez

    2013-03-01

    Full Text Available La enseñanza de la botánica se ha visto atravesada por el discurso de la interdisciplinariedad de las ciencias, las competencias científicas y la primacía de otros saberes útiles en contexto, entre otros aspectos que han llevado a pensar que ésta no se enseña, por tal razón, es pertinente indagar a través de los trayectos de práctica, cómo se aborda lo botánico en la escuela tomando como eje principal los saberes pedagógicos que circulan en los maestros que enseñan Biología alrededor de la botánica, ésta desde del marco de las ciencias naturales. Es así, que para lograr visibilizar dichos saberes se recurrió a la mirada arqueológica –genealógica, donde se realizó el rastreo de algunos documentos institucionales e investigativos, las charlas con cinco maestros en torno a su ser y quehacer y el análisis de los anteriores elementos desde la relación sujeto, saber y poder. Con base en lo anterior, se encontró que en la escuela circulan algunos saberes relacionados con la Botánica, los cuales son trabajados desde aspectos taxonómicos y netamente Biológicos. Además, de visibilizarse que en las instituciones educativas y maestros con los que se trabajó conciben la enseñanza de la Botánica, se como un pretexto que contribuye a desarrollar determinadas competencias científicas en la escuela.

  11. Fuzzy Rules for Ant Based Clustering Algorithm

    Directory of Open Access Journals (Sweden)

    Amira Hamdi

    2016-01-01

    Full Text Available This paper provides a new intelligent technique for semisupervised data clustering problem that combines the Ant System (AS algorithm with the fuzzy c-means (FCM clustering algorithm. Our proposed approach, called F-ASClass algorithm, is a distributed algorithm inspired by foraging behavior observed in ant colonyT. The ability of ants to find the shortest path forms the basis of our proposed approach. In the first step, several colonies of cooperating entities, called artificial ants, are used to find shortest paths in a complete graph that we called graph-data. The number of colonies used in F-ASClass is equal to the number of clusters in dataset. Hence, the partition matrix of dataset founded by artificial ants is given in the second step, to the fuzzy c-means technique in order to assign unclassified objects generated in the first step. The proposed approach is tested on artificial and real datasets, and its performance is compared with those of K-means, K-medoid, and FCM algorithms. Experimental section shows that F-ASClass performs better according to the error rate classification, accuracy, and separation index.

  12. The direct and ecological costs of an ant-plant symbiosis.

    Science.gov (United States)

    Frederickson, Megan E; Ravenscraft, Alison; Miller, Gabriel A; Arcila Hernández, Lina M; Booth, Gregory; Pierce, Naomi E

    2012-06-01

    How strong is selection for cheating in mutualisms? The answer depends on the type and magnitude of the costs of the mutualism. Here we investigated the direct and ecological costs of plant defense by ants in the association between Cordia nodosa, a myrmecophytic plant, and Allomerus octoarticulatus, a phytoecious ant. Cordia nodosa trees produce food and housing to reward ants that protect them against herbivores. For nearly 1 year, we manipulated the presence of A. octoarticulatus ants and most insect herbivores on C. nodosa in a full-factorial experiment. Ants increased plant growth when herbivores were present but decreased plant growth when herbivores were absent, indicating that hosting ants can be costly to plants. However, we did not detect a cost to ant colonies of defending host plants against herbivores. Although this asymmetry in costs suggests that the plants may be under stronger selection than the ants to cheat by withholding investment in their partner, the costs to C. nodosa are probably at least partly ecological, arising because ants tend scale insects on their host plants. We argue that ecological costs should favor resistance or traits other than cheating and thus that neither partner may face much temptation to cheat.

  13. Competitive assembly of South Pacific invasive ant communities

    Directory of Open Access Journals (Sweden)

    Sarty Megan

    2009-01-01

    Full Text Available Abstract Background The relative importance of chance and determinism in structuring ecological communities has been debated for nearly a century. Evidence for determinism or assembly rules is often evaluated with null models that randomize the occurrence of species in particular locales. However, analyses of the presence or absence of species ignores the potential influence of species abundances, which have long been considered of major importance on community structure. Here, we test for community assembly rules in ant communities on small islands of the Tokelau archipelago using both presence-absence and abundance data. We conducted three sets of analyses on two spatial scales using three years of sampling data from 39 plots on 11 islands. Results First, traditional null model tests showed support for negative species co-occurrence patterns among plots within islands, but not among islands. A plausible explanation for this result is that analyses at larger spatial scales merge heterogeneous habitats that have considerable effects on species occurrences. Second, analyses of ant abundances showed that samples with high ant abundances had fewer species than expected by chance, both within and among islands. One ant species, the invasive yellow crazy ant Anoplolepis gracilipes, appeared to have a particularly strong effect on community structure correlated with its abundance. Third, abundances of most ant species were inversely correlated with the abundances of all other ants at both spatial scales. This result is consistent with competition theory, which predicts species distributions are affected by diffuse competition with suites of co-occurring species. Conclusion Our results support a pluralistic explanation for ant species abundances and assembly. Both stochastic and deterministic processes interact to determine ant community assembly, though abundance patterns clearly drive the deterministic patterns in this community. These deterministic

  14. Exploring with PAM: Prospecting ANTS Missions for Solar System Surveys

    Science.gov (United States)

    Clark, P. E.; Rilee, M. L.; Curtis, S. A.

    2003-01-01

    ANTS (Autonomous Nano-Technology Swarm), a large (1000 member) swarm of nano to picoclass (10 to 1 kg) totally autonomous spacecraft, are being developed as a NASA advanced mission concept. ANTS, based on a hierarchical insect social order, use an evolvable, self-similar, hierarchical neural system in which individual spacecraft represent the highest level nodes. ANTS uses swarm intelligence attained through collective, cooperative interactions of the nodes at all levels of the system. At the highest levels this can take the form of cooperative, collective behavior among the individual spacecraft in a very large constellation. The ANTS neural architecture is designed for totally autonomous operation of complex systems including spacecraft constellations. The ANTS (Autonomous Nano Technology Swarm) concept has a number of possible applications. A version of ANTS designed for surveying and determining the resource potential of the asteroid belt, called PAM (Prospecting ANTS Mission), is examined here.

  15. Abordaje de la sexualidad en la adolescencia

    Directory of Open Access Journals (Sweden)

    H. Francisca Corona, Dra.

    2015-01-01

    Los clínicos que atienden adolescentes necesitan saber sobre el desarrollo general y psicosexual del adolescente, las tendencias que rodean sus conductas sexuales, los beneficios y riesgos que acompañan a estas conductas y los recursos y las intervenciones que están disponibles. La información que ofrezcan debe ser precisa, completa y libre de prejuicios, para que puedan tomar decisiones saludables y seguras.

  16. Os jovens e as relações com o saber: elementos para construção de uma pesquisa

    Directory of Open Access Journals (Sweden)

    Lucas Martinez

    2016-12-01

    Full Text Available Este trabalho busca aprofundar alguns aspectos  teóricos de uma pesquisa de mestrado intitulada Os jovens no ensino fundamental e a relação com o saber: um estudo de caso no município de Santa Maria/RS. A pesquisa tem por objetivo refletir sobre o processo de escolarização de jovens com mais de 15 anos de idade que ainda se encontram no Ensino Fundamental visando compreender como os jovens se relacionam com o saber. A distorção idade-série, a produção das situações de fracasso escolar, os índices de avaliação nacional, todos estes corroboram para a evidência deste tema. Compreender quem são os jovens, quais as relações que eles estabelecem entre o saber escolar e em até que ponto a escola privilegia a construção dessa relação, quais as culturas que permeiam a escola e de que forma podemos nos aproximar deles para superar as dificuldades no trajeto escolar e conduzir o processo formativo ultrapassando a distorção idade-série torna-se o eixo central de nossa reflexão.

  17. Species diversity and distribution patterns of the ants of Amazonian Ecuador.

    Directory of Open Access Journals (Sweden)

    Kari T Ryder Wilkie

    2010-10-01

    Full Text Available Ants are among the most diverse, abundant and ecologically significant organisms on earth. Although their species richness appears to be greatest in the New World tropics, global patterns of ant diversity and distribution are not well understood. We comprehensively surveyed ant diversity in a lowland primary rainforest in Western Amazonia, Ecuador using canopy fogging, pitfall traps, baits, hand collecting, mini-Winkler devices and subterranean probes to sample ants. A total of 489 ant species comprising 64 genera in nine subfamilies were identified from samples collected in only 0.16 square kilometers. The most species-rich genera were Camponotus, Pheidole, Pseudomyrmex, Pachycondyla, Brachymyrmex, and Crematogaster. Camponotus and Pseudomyrmex were most diverse in the canopy, while Pheidole was most diverse on the ground. The three most abundant ground-dwelling ant genera were Pheidole, Solenopsis and Pyramica. Crematogaster carinata was the most abundant ant species in the canopy; Wasmannia auropunctata was most abundant on the ground, and the army ant Labidus coecus was the most abundant subterranean species. Ant species composition among strata was significantly different: 80% of species were found in only one stratum, 17% in two strata, and 3% in all three strata. Elevation and the number of logs and twigs available as nest sites were significant predictors of ground-dwelling ant species richness. Canopy species richness was not correlated with any ecological variable measured. Subterranean species richness was negatively correlated with depth in the soil. When ant species were categorized using a functional group matrix based on diet, nest-site preference and foraging ecology, the greatest diversity was found in Omnivorous Canopy Nesters. Our study indicates ant species richness is exceptionally high at Tiputini. We project 647-736 ant species in this global hotspot of biodiversity. Considering the relatively small area surveyed, this

  18. Egg-laying butterflies distinguish predaceous ants by sight.

    Science.gov (United States)

    Sendoya, Sebastián F; Freitas, André V L; Oliveira, Paulo S

    2009-07-01

    Information about predation risks is critical for herbivorous insects, and natural selection favors their ability to detect predators before oviposition and to select enemy-free foliage when offspring mortality risk is high. Food plants are selected by ovipositing butterflies, and offspring survival frequently varies among plants because of variation in the presence of predators. Eunica bechina butterflies oviposit on Caryocar brasiliense, an ant-defended plant. Experiments with dried Camponotus and Cephalotes ants pinned to leaves revealed that butterflies use ant size and form as visual cues to avoid ovipositing on plant parts occupied by ants more likely to kill larval offspring. Presence of sap-sucking bugs did not affect butterfly oviposition. This is the first demonstration that visual recognition of predators can mediate egg-laying decisions by an insect herbivore and that an insect will discriminate among different species of potential predators. This unusual behavioral capability permits specialization on a risky, ant-defended food plant.

  19. Protection of Vochysia elliptica (Vochysiaceae by a nectar-thieving ant

    Directory of Open Access Journals (Sweden)

    G. Q. ROMERO

    Full Text Available Vochysia elliptica (Vochysiaceae is a shrubby plant, which does not have EFNs. Camponotus ants thieve nectar, and can decrease plant fitness by making flowers less attractive to pollinators. However, ants remove herbivores, wich can be beneficial. Results show that plants from which ants were excluded had lower rates of termite (simulated herbivore removal than did plants visited by ants. Plants accessible to ants showed higher rates of termite removal in the base of leaves and in the inflorescence, than in the tip of leaves. This occurs because ants must pass through the principal axis to reach the inflorescence. Conclusive results of this cost/benefit analysis of the Camponotus sp. presence for V. elliptica can be obtained, with experimental manipulations.

  20. Benefits conferred by "timid" ants: active anti-herbivore protection of the rainforest tree Leonardoxa africana by the minute ant Petalomyrmex phylax.

    Science.gov (United States)

    Gaume, Laurence; McKey, Doyle; Anstett, Marie-Charlotte

    1997-10-01

    In this study, we demonstrate that an important benefit provided by the small host-specific ant Petalomyrmex phylax to its host plant Leonardoxa africana is efficient protection against herbivores. We estimate that in the absence of ants, insect herbivory would reduce the leaf area by about one-third. This contributes considerably to the fitness of the plant. Our estimates take into account not only direct damage, such as removal of leaf surface by chewing insects, but also the effects of sucking insects on leaf growth and expansion. Sucking insects are numerically predominant in this system, and the hitherto cryptic effects of ant protection against the growth-reducing effects of sucking insects accounted for half of the total estimated benefit of ant protection. We propose that the small size of workers confers a distinct advantage in this system. Assuming that resource limitation implies a trade off between size and number of ants, and given the small size of phytophagous insects that attack Leonardoxa, we conclude that fine-grained patrolling by a large number of small workers maximises protection of young leaves of this plant. Since herbivores are small and must complete their development on the young leaves of Leonardoxa, and since a high patrolling density is required for a fine-grained search for these enemies, numerous small ants should provide the most effective protection of young leaves of Leonardoxa. We also discuss other factors that may have influenced worker size in this ant.

  1. Competence of Litter Ants for Rapid Biodiversity Assessments

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    T. H. Saumya E. Silva

    2017-01-01

    Full Text Available Rapid Biodiversity Assessment approaches associated with focusing taxa have overcome many of the problems related to large scale surveys. This study examined the suitability of litter ants as a focusing taxon by checking whether diversity and species assemblages of litter ants reflect the overall picture of arthropod diversity and assemblages in leaf litter in two vegetation types: secondary forest and pine plantation in Upper Hanthana forest reserve, Sri Lanka. In each vegetation type, arthropods were sampled using three sampling methods (Winkler extraction, hand collection, and pitfall traps along three 100 m line transects. From the two sites, 1887 litter ants (34 species and 3488 litter arthropods (52 species were collected. Species assemblages composition of both ants and other arthropods differed significantly between the two sites (ANOSIM, p=0.001 with both groups generating distinct clusters for the two sites (SIMPROF, p=0.001. But there was no significant correlation (p>0.05 between abundance and richness of litter ants and those of other arthropods in both vegetation types. The overall finding suggests that the litter ants do not reflect the holistic picture of arthropod diversity and assemblages in leaf litter, but the quality of the habitat for the survival of all litter arthropods.

  2. 15 years of VLT/UVES OH intensities and temperatures in comparison with TIMED/SABER data

    Science.gov (United States)

    Noll, Stefan; Kimeswenger, Stefan; Proxauf, Bastian; Unterguggenberger, Stefanie; Kausch, Wolfgang; Jones, Amy M.

    2017-10-01

    The high-resolution echelle spectrograph UVES of the Very Large Telescope at Cerro Paranal in Chile has been regularly operated since April 2000. Thus, UVES archival data originally taken for astronomical projects but also including sky emission can be used to study airglow variations on a time scale longer than a solar cycle. Focusing on OH emission and observations until March 2015, we considered about 3000 high-quality spectra from two instrumental set-ups centred on 760 and 860 nm, which cover about 380 nm each. These data allowed us to measure line intensities for several OH bands in order to derive band intensities and rotational temperatures for different upper vibrational levels as a function of solar activity and observing date. The results were compared with those derived from emission and temperature profile data of the radiometer SABER on the TIMED satellite taken in the Cerro Paranal area between 2002 and 2015. In agreement with the SABER data, the long-term variations in OH intensity and temperature derived from the UVES data are dominated by the solar cycle, whereas secular trends appear to be negligible. Combining the UVES and SABER results, the solar cycle effects for the OH intensity and temperature are about 12-17% and 4-5 K per 100 sfu and do not significantly depend on the selected OH band. The data also reveal that variations of the effective OH emission layer height and air density can cause significant changes in the OH rotational temperatures due to a varying ratio of OH thermalising collisions by air molecules and OH radiation, deactivation, and destruction processes which impede the rotational relaxation. However, this effect appears to be of minor importance for the explanation of the rotational temperature variations related to the solar activity cycle, which causes only small changes in the OH emission profile.

  3. Las ciencias sociales como integración de saberes en la dimensión humana

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    Joaquín Molano Barrero

    2007-01-01

    Full Text Available La institucionalidad de la ciencia está ligada a nuestra dependencia y nuestra miseria. Tiene su proyección en la investigación, la docencia, el control geopolítico, y la expropiación de nuestros recursos. Se analizan las ciencias sociales en relación con las demás disciplinas y saberes, tomando como elemento de convergencia la dimensión humana. La reflexión sugiere ideas para abordar la naturaleza de lo humano en relación con los otros y con lo otro. Invita a pensar la vida personal y colectiva desde las instancias profundas de la sabiduría y la espiritualidad. Esta intencionalidad surge debido a las dificultades que han padecido las ciencias sociales dentro del paradigma científico de la modernidad. No vale la pena continuar inscribiendo el saber social en el marco de la formalización de la ciencia. Eello ha demandado costos muy altos como la pérdida de la ancestralidad, la identidad y la construcción de escenarios de vida y libertad. La ciencia ha cerrado el horizonte de lo social, ha fragmentado los saberes y ha proyectado un vacío de humanidad. Las humanidades convocan a la ciencia y a las ciencias sociales a crear nuevas realidades e imaginarios de lo social, con una actitud crítica y con valores esenciales. Lo social es imprescindible en la educación y hace parte del compromiso de toda acción pedagógica, consistente en asumir conscientemente la vida para crear entre nosotros una existencia con sentido de pertenencia y de humanidad. Imposible crecer sin una buena dosis de justicia, de sabiduría, de alimento (amor y de autoconocimiento

  4. Asymmetric dispersal and colonization success of Amazonian plant-ants queens.

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    Emilio M Bruna

    Full Text Available The dispersal ability of queens is central to understanding ant life-history evolution, and plays a fundamental role in ant population and community dynamics, the maintenance of genetic diversity, and the spread of invasive ants. In tropical ecosystems, species from over 40 genera of ants establish colonies in the stems, hollow thorns, or leaf pouches of specialized plants. However, little is known about the relative dispersal ability of queens competing for access to the same host plants.We used empirical data and inverse modeling--a technique developed by plant ecologists to model seed dispersal--to quantify and compare the dispersal kernels of queens from three Amazonian ant species that compete for access to host-plants. We found that the modal colonization distance of queens varied 8-fold, with the generalist ant species (Crematogaster laevis having a greater modal distance than two specialists (Pheidole minutula, Azteca sp. that use the same host-plants. However, our results also suggest that queens of Azteca sp. have maximal distances that are four-sixteen times greater than those of its competitors.We found large differences between ant species in both the modal and maximal distance ant queens disperse to find vacant seedlings used to found new colonies. These differences could result from interspecific differences in queen body size, and hence wing musculature, or because queens differ in their ability to identify potential host plants while in flight. Our results provide support for one of the necessary conditions underlying several of the hypothesized mechanisms promoting coexistence in tropical plant-ants. They also suggest that for some ant species limited dispersal capability could pose a significant barrier to the rescue of populations in isolated forest fragments. Finally, we demonstrate that inverse models parameterized with field data are an excellent means of quantifying the dispersal of ant queens.

  5. Disease dynamics in a specialized parasite of ant societies

    DEFF Research Database (Denmark)

    Andersen, Sandra Breum; Ferrari, Matthew; Evans, Harry C.

    2012-01-01

    Coevolution between ant colonies and their rare specialized parasites are intriguing, because lethal infections of workers may correspond to tolerable chronic diseases of colonies, but the parasite adaptations that allow stable coexistence with ants are virtually unknown. We explore the trade......-offs experienced by Ophiocordyceps parasites manipulating ants into dying in nearby graveyards. We used field data from Brazil and Thailand to parameterize and fit a model for the growth rate of graveyards. We show that parasite pressure is much lower than the abundance of ant cadavers suggests...

  6. Density-dependent benefits in ant-hemipteran mutualism? The case of the ghost ant Tapinoma melanocephalum (Hymenoptera: Formicidae and the invasive mealybug Phenacoccus solenopsis (Hemiptera: Pseudococcidae.

    Directory of Open Access Journals (Sweden)

    Aiming Zhou

    Full Text Available Although density-dependent benefits to hemipterans from ant tending have been measured many times, few studies have focused on integrated effects such as interactions between ant tending, natural enemy density, and hemipteran density. In this study, we tested whether the invasive mealybug Phenacoccus solenopsis is affected by tending by ghost ants (Tapinoma melanocephalum, the presence of parasitoids, mealybug density, parasitoid density and interactions among these factors. Our results showed that mealybug colony growth rate and percentage parasitism were significantly affected by ant tending, parasitoid presence, and initial mealybug density separately. However, there were no interactions among the independent factors. There were also no significant interactions between ant tending and parasitoid density on either mealybug colony growth rate or percentage parasitism. Mealybug colony growth rate showed a negative linear relationship with initial mealybug density but a positive linear relationship with the level of ant tending. These results suggest that benefits to mealybugs are density-independent and are affected by ant tending level.

  7. Ant exclusion in citrus over an 8-year period reveals a pervasive yet changing effect of ants on a Mediterranean spider assemblage.

    Science.gov (United States)

    Mestre, L; Piñol, J; Barrientos, J A; Espadaler, X

    2013-09-01

    Ants and spiders are ubiquitous generalist predators that exert top-down control on herbivore populations. Research shows that intraguild interactions between ants and spiders can negatively affect spider populations, but there is a lack of long-term research documenting the strength of such interactions and the potentially different effects of ants on the diverse array of species in a spider assemblage. Similarly, the suitability of family-level surrogates for finding patterns revealed by species-level data (taxonomic sufficiency) has almost never been tested in spider assemblages. We present a long-term study in which we tested the impact of ants on the spider assemblage of a Mediterranean citrus grove by performing sequential 1-year experimental exclusions on tree canopies for 8 years. We found that ants had a widespread influence on the spider assemblage, although the effect was only evident in the last 5 years of the study. During those years, ants negatively affected many spiders, and effects were especially strong for sedentary spiders. Analyses at the family level also detected assemblage differences between treatments, but they concealed the different responses to ant exclusion shown by some related spider species. Our findings show that the effects of experimental manipulations in ecology can vary greatly over time and highlight the need for long-term studies to document species interactions.

  8. SIGNIFICADOS DE LA PERTIENENCIA Y EL IMPACTO SOCIAL DE LA INVESTIGACIÓN JURÍDICA EN EL PROGRAMA DE DERECHO DE LA UNIVERSIDAD DE ANTIOQUIA EN EL MARCO DE LA LEY 1286 DE 2009 AVANCE DE INVESTIGACIÓN

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    Nora Alba Cossio Acevedo

    2012-01-01

    Full Text Available El propósito de este escrito es presentar los avances de la investigación titulada: “Pertinencia e Impacto Social de la Investigación Jurídica: el caso del Programa de Derecho de la Universidad de Antioquia 1992-2009, acta CODI No. 589 del 9 de noviembre de 2010”, indagación que resulta de gran actualidad para revisar el uso social de su saber investigativo y determinar qué acciones y proyectos debe implementar la Facultad de Derecho para enfrentar los retos que le plantea la Ley 1286 de 2009. Durante su práctica investigativa los docentes del programa han construido los significados de las categorías centrales del problema “pertinencia” e “impacto social”; este texto los relaciona e interpreta en virtud de que el “significado” es el sentido que se le otorga a las cosas o a las acciones, surge de la relación con otros o de la experiencia, se afianza o modifica con el paso del tiempo y ante todo determina las prácticas, las acciones y en general, la forma en que los seres humanos viven sus procesos o interactúan con el mundo de la vida.

  9. Alfasecuencialización: la enseñanza del cine en la era del audiovisual Sequential literacy: the teaching of cinema in the age of audio-visual speech

    Directory of Open Access Journals (Sweden)

    José Antonio Palao Errando

    2007-10-01

    Full Text Available En la llamada «sociedad de la información» los estudios sobre cine se han visto diluidos en el abordaje pragmático y tecnológico del discurso audiovisual, así como la propia fruición del cine se ha visto atrapada en la red del DVD y del hipertexto. El propio cine reacciona ante ello a través de estructuras narrativas complejas que lo alejan del discurso audiovisual estándar. La función de los estudios sobre cine y de su enseñanza universitaria debe ser la reintroducción del sujeto rechazado del saber informativo por medio de la interpretación del texto fílmico. In the so called «information society», film studies have been diluted in the pragmatic and technological approaching of the audiovisual speech, as well as the own fruition of the cinema has been caught in the net of DVD and hypertext. The cinema itself reacts in the face of it through complex narrative structures that take it away from the standard audio-visual speech. The function of film studies at the university education should be the reintroduction of the rejected subject of the informative knowledge by means of the interpretation of film text.

  10. Just follow your nose: homing by olfactory cues in ants.

    Science.gov (United States)

    Steck, Kathrin

    2012-04-01

    How is an ant-equipped with a brain that barely exceeds the size of a pinhead-capable of achieving navigational marvels? Even though evidences suggest that navigation is a multimodal process, ants heavily depend on olfactory cues-of pheromonal and non-pheromonal nature-for foraging and orientation. Recent studies have directed their attention to the efficiency of pheromone trail networks. Advances in neurophysiological techniques make it possible to investigate trail pheromone processing in the ant's brain. In addition to relying on pheromone odours, ants also make use of volatiles emanating from the nest surroundings. Deposited in the vicinity of the nest, these home-range markings help the ants to home after a foraging run. Furthermore, olfactory landmarks associated with the nest enhance ants' homing abilities. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Behind every great ant, there is a great gut

    DEFF Research Database (Denmark)

    Poulsen, Michael; Sapountzis, Panagiotis

    2012-01-01

    on the potential contribution of the ants’ gut symbionts. This issue of Molecular Ecology contains a study by Anderson et al. (2012), who take a comparative approach to explore the link between trophic levels and ant microbiomes, specifically, to address three main questions: (i) Do closely related herbivorous...... conserved gut microbiomes, suggesting symbiont functions that directly relate to dietary preference of the ant host. These findings suggest an ecological role of gut symbionts in ants, for example, in metabolism and/or protection, and the comparative approach taken supports a model of co-evolution between...... ant species and specific core symbiont microbiomes. This study, thereby, highlights the omnipresence and importance of gut symbioses—also in the Hymenoptera—and suggests that these hitherto overlooked microbes likely have contributed to the ecological success of the ants....

  12. Arboreal ant colonies as 'hot-points' of cryptic diversity for myrmecophiles: the weaver ant Camponotus sp. aff. textor and its interaction network with its associates.

    Science.gov (United States)

    Pérez-Lachaud, Gabriela; Lachaud, Jean-Paul

    2014-01-01

    Systematic surveys of macrofaunal diversity within ant colonies are lacking, particularly for ants nesting in microhabitats that are difficult to sample. Species associated with ants are generally small and rarely collected organisms, which makes them more likely to be unnoticed. We assumed that this tendency is greater for arthropod communities in microhabitats with low accessibility, such as those found in the nests of arboreal ants that may constitute a source of cryptic biodiversity. We investigated the invertebrate diversity associated with an undescribed, but already threatened, Neotropical Camponotus weaver ant. As most of the common sampling methods used in studies of ant diversity are not suited for evaluating myrmecophile diversity within ant nests, we evaluated the macrofauna within ant nests through exhaustive colony sampling of three nests and examination of more than 80,000 individuals. We identified invertebrates from three classes belonging to 18 taxa, some of which were new to science, and recorded the first instance of the co-occurrence of two brood parasitoid wasp families attacking the same ant host colony. This diversity of ant associates corresponded to a highly complex interaction network. Agonistic interactions prevailed, but the prevalence of myrmecophiles was remarkably low. Our data support the hypothesis of the evolution of low virulence in a variety of symbionts associated with large insect societies. Because most myrmecophiles found in this work are rare, strictly specific, and exhibit highly specialized biology, the risk of extinction for these hitherto unknown invertebrates and their natural enemies is high. The cryptic, far unappreciated diversity within arboreal ant nests in areas at high risk of habitat loss qualifies these nests as 'hot-points' of biodiversity that urgently require special attention as a component of conservation and management programs.

  13. Arboreal ant colonies as 'hot-points' of cryptic diversity for myrmecophiles: the weaver ant Camponotus sp. aff. textor and its interaction network with its associates.

    Directory of Open Access Journals (Sweden)

    Gabriela Pérez-Lachaud

    Full Text Available INTRODUCTION: Systematic surveys of macrofaunal diversity within ant colonies are lacking, particularly for ants nesting in microhabitats that are difficult to sample. Species associated with ants are generally small and rarely collected organisms, which makes them more likely to be unnoticed. We assumed that this tendency is greater for arthropod communities in microhabitats with low accessibility, such as those found in the nests of arboreal ants that may constitute a source of cryptic biodiversity. MATERIALS AND METHODS: We investigated the invertebrate diversity associated with an undescribed, but already threatened, Neotropical Camponotus weaver ant. As most of the common sampling methods used in studies of ant diversity are not suited for evaluating myrmecophile diversity within ant nests, we evaluated the macrofauna within ant nests through exhaustive colony sampling of three nests and examination of more than 80,000 individuals. RESULTS: We identified invertebrates from three classes belonging to 18 taxa, some of which were new to science, and recorded the first instance of the co-occurrence of two brood parasitoid wasp families attacking the same ant host colony. This diversity of ant associates corresponded to a highly complex interaction network. Agonistic interactions prevailed, but the prevalence of myrmecophiles was remarkably low. CONCLUSIONS: Our data support the hypothesis of the evolution of low virulence in a variety of symbionts associated with large insect societies. Because most myrmecophiles found in this work are rare, strictly specific, and exhibit highly specialized biology, the risk of extinction for these hitherto unknown invertebrates and their natural enemies is high. The cryptic, far unappreciated diversity within arboreal ant nests in areas at high risk of habitat loss qualifies these nests as 'hot-points' of biodiversity that urgently require special attention as a component of conservation and management

  14. Perspectivas y proyección profesional de la comunicación social

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    Mónica Salazar Gómez

    2011-01-01

    de la comunicación social, las diversas posturas sobre el deber ser de la carrera, las expectativas frente a lo que debe saber hacer un comunicador social y el devenir de la profesión en relación con las necesidades del país y del mercado laboral. La tesis central es contrastar las diferentes comprensiones que tienen algunos actores frente a la proyección de la carrera. Creemos que a pesar de la mirada mediática que generalmente se tiene, la comunicación social debe ser entendida más como constructora de sentidos, articuladora de procesos sociales y generadora de puentes entre diversos actores, para asumir un rol de transformación social.

  15. Understanding Short-Term Nonmigrating Tidal Variability in the Ionospheric Dynamo Region from SABER Using Information Theory and Bayesian Statistics

    Science.gov (United States)

    Kumari, K.; Oberheide, J.

    2017-12-01

    Nonmigrating tidal diagnostics of SABER temperature observations in the ionospheric dynamo region reveal a large amount of variability on time-scales of a few days to weeks. In this paper, we discuss the physical reasons for the observed short-term tidal variability using a novel approach based on Information theory and Bayesian statistics. We diagnose short-term tidal variability as a function of season, QBO, ENSO, and solar cycle and other drivers using time dependent probability density functions, Shannon entropy and Kullback-Leibler divergence. The statistical significance of the approach and its predictive capability is exemplified using SABER tidal diagnostics with emphasis on the responses to the QBO and solar cycle. Implications for F-region plasma density will be discussed.

  16. O uso do saber estatístico nos discursos acadêmicos da alfabetização

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    Renata Sperrhake

    2012-01-01

    Full Text Available O presente texto analisa como os discursos da alfabetização, do analfabetismo e do alfabetismo/letramento utilizam o saber estatístico. Para tanto, realizou-se uma busca em acervos digitais de revistas especializadas em Educação e Estatística e no Portal de Teses da CAPES. A partir do corpus selecionado, é possível perceber as seguintes formas de utilização: 1 estatísticas utilizadas como material empírico; 2 estatísticas utilizadas como procedimento metodológico; 3 referência ao saber estatístico. Além de mostrar como o saber estatístico é utilizado, a análise das produções acadêmicas nos fez perceber outros dois pontos: o aparecimento de níveis de alfabetismo/letramento; e uma mudança quanto à forma de entender a relação do sujeito com a leitura e a escrita.Abstract The present paper analyzes how discourses of literacy, illiteracy and alphabetic literacy have used statistical knowledge. We carried out a search into digital files of journals specialized in Education and Statistics, as well as into CAPES Thesis Database. From the selected corpus, it is possible to perceive the following kinds of uses: 1 statistics used as empirical material; 2 statistics used as methodological procedure; 3 reference to statistical knowledge. Besides evidencing how the statistical knowledge has been used, the analysis of academic productions has enabled us to perceive other two points: the appearance of levels of alphabetic literacy, and the change in the understanding of the relationship of the subject with reading and writing.

  17. Histrionicotoxin alkaloids finally detected in an ant

    DEFF Research Database (Denmark)

    Jones, Tappey H.; Adams, Rachelle Martha Marie; Spande, Thomas F.

    2012-01-01

    Workers of the ant Carebarella bicolor collected in Panama were found to have two major poison-frog alkaloids, cis- and trans-fused decahydroquinolines (DHQs) of the 269AB type, four minor 269AB isomers, two minor 269B isomers, and three isomers of DHQ 271D. For the first time in an ant, however......) sp., were found to have a very similar DHQ complex but failed to show HTXs. Several new DHQ alkaloids of MW 271 (named in the frog as 271G) are reported from the above ants that have both m/z 202 and 204 as major fragment ions, unlike the spectrum seen for the poison-frog alkaloid 271D, which has...... only an m/z 204 base peak. Found also for the first time in skin extracts from the comparison frog Oophaga granulifera of Costa Rica is a trace DHQ of MW 273. It is coded as 273F in the frog; a different isomer is found in the ant....

  18. Neuromodulation of Nestmate Recognition Decisions by Pavement Ants.

    Science.gov (United States)

    Bubak, Andrew N; Yaeger, Jazmine D W; Renner, Kenneth J; Swallow, John G; Greene, Michael J

    2016-01-01

    Ant colonies are distributed systems that are regulated in a non-hierarchical manner. Without a central authority, individuals inform their decisions by comparing information in local cues to a set of inherent behavioral rules. Individual behavioral decisions collectively change colony behavior and lead to self-organization capable of solving complex problems such as the decision to engage in aggressive societal conflicts with neighbors. Despite the relevance to colony fitness, the mechanisms that drive individual decisions leading to cooperative behavior are not well understood. Here we show how sensory information, both tactile and chemical, and social context-isolation, nestmate interaction, or fighting non-nestmates-affects brain monoamine levels in pavement ants (Tetramorium caespitum). Our results provide evidence that changes in octopamine and serotonin in the brains of individuals are sufficient to alter the decision by pavement ants to be aggressive towards non-nestmate ants whereas increased brain levels of dopamine correlate to physical fighting. We propose a model in which the changes in brain states of many workers collectively lead to the self-organization of societal aggression between neighboring colonies of pavement ants.

  19. Antílope

    Directory of Open Access Journals (Sweden)

    Pedro Anderson Martinho Moçambique

    2015-10-01

    Full Text Available Essa espécie de antílope só é encontrada em território angolano, sendo assim um símbolo nacional. Segundo a mitologia africana é símbolo de vivacidade, velocidade e beleza - Angola.

  20. Antílope

    Directory of Open Access Journals (Sweden)

    Pedro Anderson Martinho Moçambique

    2011-04-01

    Full Text Available Essa espécie de antílope só é encontrada em território angolano, sendo assim um símbolo nacional. Segundo a mitologia africana é símbolo de vivacidade, velocidade e beleza - Angola.

  1. Application of an Image Tracking Algorithm in Fire Ant Motion Experiment

    Directory of Open Access Journals (Sweden)

    Lichuan Gui

    2009-04-01

    Full Text Available An image tracking algorithm, which was originally used with the particle image velocimetry (PIV to determine velocities of buoyant solid particles in water, is modified and applied in the presented work to detect motion of fire ant on a planar surface. A group of fire ant workers are put to the bottom of a tub and excited with vibration of selected frequency and intensity. The moving fire ants are captured with an image system that successively acquires image frames of high digital resolution. The background noise in the imaging recordings is extracted by averaging hundreds of frames and removed from each frame. The individual fire ant images are identified with a recursive digital filter, and then they are tracked between frames according to the size, brightness, shape, and orientation angle of the ant image. The speed of an individual ant is determined with the displacement of its images and the time interval between frames. The trail of the individual fire ant is determined with the image tracking results, and a statistical analysis is conducted for all the fire ants in the group. The purpose of the experiment is to investigate the response of fire ants to the substrate vibration. Test results indicate that the fire ants move faster after being excited, but the number of active ones are not increased even after a strong excitation.

  2. Empresa bajo incertidumbre en el precio: modelo con dos destinos y un mercado de futuros

    Directory of Open Access Journals (Sweden)

    Álvarez López, Alberto A.

    2008-01-01

    Full Text Available En este trabajo se desarrolla un modelo para una empresa competitiva que produce una cantidad determinada de un bien, la cual debe repartir entre dos fines distintos, para los que se tienen diferentes precios. La empresa debe decidir la cantidad que destinará a cada fin antes de conocer el precio para uno de ellos; para este fin, existe además un mercado de futuros, por lo que también debe decidir la cantidad que venderá en ese mercado. Tras presentar el modelo, se interpretan económicamente las diferentes soluciones del problema, y se estudian algunas de sus propiedades.

  3. Interactions Increase Forager Availability and Activity in Harvester Ants.

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    Evlyn Pless

    Full Text Available Social insect colonies use interactions among workers to regulate collective behavior. Harvester ant foragers interact in a chamber just inside the nest entrance, here called the 'entrance chamber'. Previous studies of the activation of foragers in red harvester ants show that an outgoing forager inside the nest experiences an increase in brief antennal contacts before it leaves the nest to forage. Here we compare the interaction rate experienced by foragers that left the nest and ants that did not. We found that ants in the entrance chamber that leave the nest to forage experienced more interactions than ants that descend to the deeper nest without foraging. Additionally, we found that the availability of foragers in the entrance chamber is associated with the rate of forager return. An increase in the rate of forager return leads to an increase in the rate at which ants descend to the deeper nest, which then stimulates more ants to ascend into the entrance chamber. Thus a higher rate of forager return leads to more available foragers in the entrance chamber. The highest density of interactions occurs near the nest entrance and the entrances of the tunnels from the entrance chamber to the deeper nest. Local interactions with returning foragers regulate both the activation of waiting foragers and the number of foragers available to be activated.

  4. “Matrices de aprendizaje” emancipadoras. OVNI (Observatorio de Video no Identificado) y el videoactivismo

    OpenAIRE

    Álvarez Blanco, María Palmar

    2017-01-01

    Partiendo de la premisa de que no estamos solos ante una crisis económica sino ante una crisis planetaria y de civilización marcada por la desaparición de los derechos humanos y los derechos de la naturaleza, este ensayo revisa el concepto de colonialidad del saber o “colonialismo interno” (Rivera Cusicanqui) junto al de matriz del aprendizaje capitalista como estructura instituyente tanto de una psique colonizadora como de una subalterna y de las rela...

  5. As palavras do saber e do sabor: A gastronomia como objecto de descoberta no processo de ensino / aprendizagem do PLE e PL2

    OpenAIRE

    Ferreira, Maria de Lurdes Carvalho

    2011-01-01

    Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Ensino do Português como Língua Segunda e Estrangeira Ao adquirir competências numa língua estrangeira, o aprendente acede à matriz cultural dos seus falantes. A gastronomia, enquanto saber e saber-fazer, constitui um dos traços identitários mais relevantes, uma vez que, respeitando variedades e especificidades, é sentida como um património comum. A gastronomia cruza vertentes diversas, d...

  6. Fluid intake rates in ants correlate with their feeding habits.

    Science.gov (United States)

    Paul, J; Roces, F

    2003-04-01

    This study investigates the techniques of nectar feeding in 11 different ant species, and quantitatively compares fluid intake rates over a wide range of nectar concentrations in four species that largely differ in their feeding habits. Ants were observed to employ two different techniques for liquid food intake, in which the glossa works either as a passive duct-like structure (sucking), or as an up- and downwards moving shovel (licking). The technique employed for collecting fluids at ad libitum food sources was observed to be species-specific and to correlate with the presence or absence of a well-developed crop in the species under scrutiny. Workers of ponerine ants licked fluid food during foraging and transported it as a droplet between their mandibles, whereas workers of species belonging to phylogenetically more advanced subfamilies, with a crop capable of storing liquids, sucked the fluid food, such as formicine ants of the genus Camponotus. In order to evaluate the performance of fluid collection during foraging, intake rates for sucrose solutions of different concentrations were measured in four ant species that differ in their foraging ecology. Scaling functions between fluid intake rates and ant size were first established for the polymorphic species, so as to compare ants of different size across species. Results showed that fluid intake rate depended, as expected and previously reported in the literature, on sugar concentration and the associated fluid viscosity. It also depended on both the species-specific feeding technique and the extent of specialization on foraging on liquid food. For similarly-sized ants, workers of two nectar-feeding ant species, Camponotus rufipes (Formicinae) and Pachycondyla villosa (Ponerinae), collected fluids with the highest intake rates, while workers of the leaf-cutting ant Atta sexdens (Myrmicinae) and a predatory ant from the Rhytidoponera impressa-complex (Ponerinae) did so with the lowest rate. Calculating the

  7. The regulation of ant colony foraging activity without spatial information.

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    Balaji Prabhakar

    Full Text Available Many dynamical networks, such as the ones that produce the collective behavior of social insects, operate without any central control, instead arising from local interactions among individuals. A well-studied example is the formation of recruitment trails in ant colonies, but many ant species do not use pheromone trails. We present a model of the regulation of foraging by harvester ant (Pogonomyrmex barbatus colonies. This species forages for scattered seeds that one ant can retrieve on its own, so there is no need for spatial information such as pheromone trails that lead ants to specific locations. Previous work shows that colony foraging activity, the rate at which ants go out to search individually for seeds, is regulated in response to current food availability throughout the colony's foraging area. Ants use the rate of brief antennal contacts inside the nest between foragers returning with food and outgoing foragers available to leave the nest on the next foraging trip. Here we present a feedback-based algorithm that captures the main features of data from field experiments in which the rate of returning foragers was manipulated. The algorithm draws on our finding that the distribution of intervals between successive ants returning to the nest is a Poisson process. We fitted the parameter that estimates the effect of each returning forager on the rate at which outgoing foragers leave the nest. We found that correlations between observed rates of returning foragers and simulated rates of outgoing foragers, using our model, were similar to those in the data. Our simple stochastic model shows how the regulation of ant colony foraging can operate without spatial information, describing a process at the level of individual ants that predicts the overall foraging activity of the colony.

  8. A produção do conhecimento: diálogo entre os diferentes saberes La producción del conocimiento: un dialogo entre los diferentes saberes Knowledge production: a dialogue among different knowledge

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    Alacoque Lorenzini Erdmann

    2006-08-01

    Full Text Available O texto aborda o diálogo necessário entre os diferentes saberes para a construçao do conhecimento e discorre sobre os avanços da Enfermagem na busca de consistência e clareza da disciplina Enfermagem. Para tanto, o texto apóia-se na transdisciplinaridade, na intersetorialidade, na complexidade e no convívio com os diferentes pares da saúde e outras áreas e na sustentação do espaço da ciência e tecnologia da Enfermagem. Questiona-se sobre que perspectivas se abrem como possibilidades de construção de conhecimentos científicos e tecnológicos num compromisso social mais responsável e solidário. O propósito é ampliar a aptidão para contextualizar e globalizar os saberes e transcender diferenças e peculiaridades na perspectiva de políticas mais qualitativas superando as fronteiras disciplinares.El texto aporta la necesidad del diálogo entre los diferentes saberes para la construcción del conocimiento y nos permite pensar sobre los progresos de la Enfermería en la búsqueda de una consistencia y claridad de la disciplina de Enfermería. Por consiguiente, el texto se fundamenta en la transdisciplinariedad, en la intersectorialidad, en la complejidad y en la convivencia con los diferentes grupos de la salud y otros áreas, así como, en la sustentación del espacio de la ciencia y la tecnología de la Enfermería. Se discute acerca de que perspectivas son abiertas como posibilidades en la construcción de dichos conocimientos científicos y tecnológicos mediante un compromiso social más responsable y solidario. El propósito es ampliar la aptitud y capacidad para contextualizar y globalizar los saberes y poder ultrapasar las diferencias y particularidades en la perspectiva de las políticas más cualitativas de manera a superar todas las fronteras o barreras disciplinarias.This text approaches the necessary dialogue among different knowledge and considers the advances within Nursing in the search for consistence and clarity

  9. A formação do professor de ciências para os anos iniciais do Ensino Fundamental e a compreensão de saberes científicos

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    Raquel Sanzovo Pires de Campos

    2016-12-01

    Full Text Available Ressaltamos neste trabalho a importância dos alunos já nos primeiros anos do Ensino Fundamental comecem a caminhar em busca do desenvolvimento de saberes científicos, possuindo certo grau de domínio, de habilidades e recursos tornando-os capazes de confrontar determinadas situações. Considerando o papel de mediador do professor que lecionará Ciências nos primeiros anos do Ensino Fundamental, há de se considerar a sua formação inicial para o desenvolvimento da compreensão do que é um indivíduo cientificamente competente uma vez que os saberes científicos não são desenvolvidos espontaneamente entre os alunos. A proposta deste estudo foi, consequentemente, investigar a noção de saberes científicos em discentes do curso de licenciatura em Pedagogia. Identificada parcialmente em apenas um quarto dos discentes investigados, destacamos a importância da construção da noção dos saberes científicos como objetivo para esta etapa da educação básica.

  10. Arboreal Ant Colonies as ‘Hot-Points’ of Cryptic Diversity for Myrmecophiles: The Weaver Ant Camponotus sp. aff. textor and Its Interaction Network with Its Associates

    Science.gov (United States)

    Pérez-Lachaud, Gabriela; Lachaud, Jean-Paul

    2014-01-01

    Introduction Systematic surveys of macrofaunal diversity within ant colonies are lacking, particularly for ants nesting in microhabitats that are difficult to sample. Species associated with ants are generally small and rarely collected organisms, which makes them more likely to be unnoticed. We assumed that this tendency is greater for arthropod communities in microhabitats with low accessibility, such as those found in the nests of arboreal ants that may constitute a source of cryptic biodiversity. Materials and Methods We investigated the invertebrate diversity associated with an undescribed, but already threatened, Neotropical Camponotus weaver ant. As most of the common sampling methods used in studies of ant diversity are not suited for evaluating myrmecophile diversity within ant nests, we evaluated the macrofauna within ant nests through exhaustive colony sampling of three nests and examination of more than 80,000 individuals. Results We identified invertebrates from three classes belonging to 18 taxa, some of which were new to science, and recorded the first instance of the co-occurrence of two brood parasitoid wasp families attacking the same ant host colony. This diversity of ant associates corresponded to a highly complex interaction network. Agonistic interactions prevailed, but the prevalence of myrmecophiles was remarkably low. Conclusions Our data support the hypothesis of the evolution of low virulence in a variety of symbionts associated with large insect societies. Because most myrmecophiles found in this work are rare, strictly specific, and exhibit highly specialized biology, the risk of extinction for these hitherto unknown invertebrates and their natural enemies is high. The cryptic, far unappreciated diversity within arboreal ant nests in areas at high risk of habitat loss qualifies these nests as ‘hot-points’ of biodiversity that urgently require special attention as a component of conservation and management programs. PMID:24941047

  11. Entre el saber y la verdad,el enigma del sujeto.

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    Luz Stella Alzate.

    2002-03-01

    Full Text Available El presente texto constituye un intento de dimensionar la posición del sujeto tanto para la filosofía como papa el psicoanálisis, como un ser estructuralmente escindido. Esto es, como un ser constituido a partir de una división estructural entre el saber y la verdad, en medio de los cuales se prefiguran el mito y el enigma como estructuras discursivas. Partiendo de esta división, se hace un breve análisis de la tragedia de Medea, de Eurípides, de la cual se obtienen algunos elementos para ilustrar la posición de algunas mujeres en lo que respecta al fenómeno de la violencia intrafamiliar.

  12. Endophytic fungi reduce leaf-cutting ant damage to seedlings

    Science.gov (United States)

    Bittleston, L. S.; Brockmann, F.; Wcislo, W.; Van Bael, S. A.

    2011-01-01

    Our study examines how the mutualism between Atta colombica leaf-cutting ants and their cultivated fungus is influenced by the presence of diverse foliar endophytic fungi (endophytes) at high densities in tropical leaf tissues. We conducted laboratory choice trials in which ant colonies chose between Cordia alliodora seedlings with high (Ehigh) or low (Elow) densities of endophytes. The Ehigh seedlings contained 5.5 times higher endophyte content and a greater diversity of fungal morphospecies than the Elow treatment, and endophyte content was not correlated with leaf toughness or thickness. Leaf-cutting ants cut over 2.5 times the leaf area from Elow relative to Ehigh seedlings and had a tendency to recruit more ants to Elow plants. Our findings suggest that leaf-cutting ants may incur costs from cutting and processing leaves with high endophyte loads, which could impact Neotropical forests by causing variable damage rates within plant communities. PMID:20610420

  13. Induced mutations in Iraqi bread wheat cv. Saber Beg

    International Nuclear Information System (INIS)

    Ibrahim, I.F.; Haidar, H.O.

    1989-01-01

    ''Saber Beg'', is a local wheat cultivar important in the semi-arid zone of Iraq where the rainfall is less than 450 mm per year. This cultivar has a good baking quality, but is of low productivity, high susceptibility to common bunt (Tilletia spp.) and to leaf rust (Puccinia recondita Rob. ex Desm.), but only in the rainy season. A mutation breeding programme using gamma irradiation has been started in 1978 to improve this cultivar. Seeds of all main tillers from M 1 plants were harvested and artificially inoculated with teliospores of Tilletia spp. All the seeds from healthy M 2 plants were inoculated again and sown in the same area. Out of 22920 M 3 plants, 244 resistant ones were selected. During subsequent screening for 4 generations, however, only 3 mutants were confirmed

  14. Significado de los saberes popular y artístico para educar en la conservación de la biodiversidad

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    Marisela de La Caridad Guerra Salcedo

    2016-01-01

    Full Text Available Resumen El presente trabajo tiene por objetivo fundamentar teóricamente el significado del saber popular y el saber artístico para la educación en la conservación de la biodiversidad desde las ciencias naturales y agrícolas en la formación de docentes de estas especialidades. Durante su desarrollo se utilizaron métodos del nivel teórico, que permitieron establecer los argumentos que se exponen. Se fundamenta la importancia de estos saberes en el tratamiento del contenido biodiversidad para contribuir a un aprendizaje significativo y con sentido personal, que posibilite motivar y sensibilizar al sujeto en el conocimiento de este recurso natural, así como en la necesidad de su conservación y uso sostenible. Ello posibilita el esclarecimiento y la creación productiva de significados respecto a la biodiversidad, lo que redundará en el enriquecimiento cultural de los estudiantes, como futuros educadores ambientales. Se definen los saberes popular y artístico. Se citan, a modo de ejemplos, actividades en las cuales están presentes. Meaning of popular and artistic knowledge for training in biodiversity conservation. ABSTRACT This work aims to theoretically substantiate the significance of popular knowledge and artistic knowledge for education in the conservation of biodiversity from the natural and agricultural sciences in the training of teachers of these specialties. During development theoretical methods, which allowed to establish the arguments presented were used. The importance of this knowledge in the treatment of content biodiversity to contribute to a meaningful learning and personal sense, which enables motivate and sensitize the subject knowledge of this natural resource and the need for its conservation and sustainable use is grounded . This enables the clarification and creation of meaning production on biodiversity, which will result in the cultural enrichment of students, as future environmental educators. The popular and

  15. Diversity of Species and Behavior of Hymenopteran Parasitoids of Ants: A Review

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    Jean-Paul Lachaud

    2012-01-01

    Full Text Available Reports of hymenopterans associated with ants involve more than 500 species, but only a fraction unambiguously pertain to actual parasitoids. In this paper, we attempt to provide an overview of both the diversity of these parasitoid wasps and the diversity of the types of interactions they have formed with their ant hosts. The reliable list of parasitoid wasps using ants as primary hosts includes at least 138 species, reported between 1852 and 2011, distributed among 9 families from 3 superfamilies. These parasitoids exhibit a wide array of biologies and developmental strategies: ecto- or endoparasitism, solitary or gregarious, and idio- or koinobiosis. All castes of ants and all developmental stages, excepting eggs, are possible targets. Some species parasitize adult worker ants while foraging or performing other activities outside the nest; however, in most cases, parasitoids attack ant larvae either inside or outside their nests. Based on their abundance and success in attacking ants, some parasitoid wasps like diapriids and eucharitids seem excellent potential models to explore how parasitoids impact ant colony demography, population biology, and ant community structure. Despite a significant increase in our knowledge of hymenopteran parasitoids of ants, most of them remain to be discovered.

  16. Entomopathogens Isolated from Invasive Ants and Tests of Their Pathogenicity

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    Maria Fernanda Miori de Zarzuela

    2012-01-01

    Full Text Available Some ant species cause severe ecological and health impact in urban areas. Many attempts have been tested to control such species, although they do not always succeed. Biological control is an alternative to chemical control and has gained great prominence in research, and fungi and nematodes are among the successful organisms controlling insects. This study aimed to clarify some questions regarding the biological control of ants. Invasive ant species in Brazil had their nests evaluated for the presence of entomopathogens. Isolated entomopathogens were later applied in colonies of Monomorium floricola under laboratory conditions to evaluate their effectiveness and the behavior of the ant colonies after treatment. The entomopathogenic nematodes Heterorhabditis sp. and Steinernema sp. and the fungi Beauveria bassiana, Metarhizium anisopliae, and Paecilomyces sp. were isolated from the invasive ant nests. M. floricola colonies treated with Steinernema sp. and Heterorhabditis sp. showed a higher mortality of workers than control. The fungus Beauveria bassiana caused higher mortality of M. floricola workers. However, no colony reduction or elimination was observed in any treatment. The defensive behaviors of ants, such as grooming behavior and colony budding, must be considered when using fungi and nematodes for biological control of ants.

  17. Kin-informative recognition cues in ants

    DEFF Research Database (Denmark)

    Nehring, Volker; Evison, Sophie E F; Santorelli, Lorenzo A

    2011-01-01

    behaviour is thought to be rare in one of the classic examples of cooperation--social insect colonies--because the colony-level costs of individual selfishness select against cues that would allow workers to recognize their closest relatives. In accord with this, previous studies of wasps and ants have...... found little or no kin information in recognition cues. Here, we test the hypothesis that social insects do not have kin-informative recognition cues by investigating the recognition cues and relatedness of workers from four colonies of the ant Acromyrmex octospinosus. Contrary to the theoretical...... prediction, we show that the cuticular hydrocarbons of ant workers in all four colonies are informative enough to allow full-sisters to be distinguished from half-sisters with a high accuracy. These results contradict the hypothesis of non-heritable recognition cues and suggest that there is more potential...

  18. Regulation and specificity of antifungal metapleural gland secretion in leaf-cutting ants

    DEFF Research Database (Denmark)

    Yek, Sze Huei; Nash, David Richard; Jensen, Annette Bruun

    2012-01-01

    significantly larger for ants challenged with virulent and mild pathogens/weeds than for controls and Escovopsis-challenged ants. We conclude that the MG defence system of leaf-cutting ants has characteristics reminiscent of an additional cuticular immune system, with specific and non-specific components......Ants have paired metapleural glands (MGs) to produce secretions for prophylactic hygiene. These exocrine glands are particularly well developed in leaf-cutting ants, but whether the ants can actively regulate MG secretion is unknown. In a set of controlled experiments using conidia of five fungi...

  19. Hidden diversity behind the zombie-ant fungus Ophiocordyceps unilateralis: four new species described from carpenter ants in Minas Gerais, Brazil.

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    Harry C Evans

    Full Text Available BACKGROUND: Ophiocordyceps unilateralis (Clavicipitaceae: Hypocreales is a fungal pathogen specific to ants of the tribe Camponotini (Formicinae: Formicidae with a pantropical distribution. This so-called zombie or brain-manipulating fungus alters the behaviour of the ant host, causing it to die in an exposed position, typically clinging onto and biting into the adaxial surface of shrub leaves. We (HCE and DPH are currently undertaking a worldwide survey to assess the taxonomy and ecology of this highly variable species. METHODS: We formally describe and name four new species belonging to the O. unilateralis species complex collected from remnant Atlantic rainforest in the south-eastern region (Zona da Mata of the State of Minas Gerais, Brazil. Fully illustrated descriptions of both the asexual (anamorph and sexual (teleomorph stages are provided for each species. The new names are registered in Index Fungorum (registration.indexfungorum.org and have received IF numbers. This paper is also a test case for the electronic publication of new names in mycology. CONCLUSIONS: We are only just beginning to understand the taxonomy and ecology of the Ophiocordyceps unilateralis species complex associated with carpenter ants; macroscopically characterised by a single stalk arising from the dorsal neck region of the ant host on which the anamorph occupies the terminal region and the teleomorph occurs as lateral cushions or plates. Each of the four ant species collected--Camponotus rufipes, C. balzani, C. melanoticus and C. novogranadensis--is attacked by a distinct species of Ophiocordyceps readily separated using traditional micromorphology. The new taxa are named according to their ant host.

  20. Desarrollo moral, valores y ética; una investigación dentro del aula

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    Zoila Rosa Vargas Cordero

    2004-01-01

    Full Text Available Utilizar en un curso de formación universitaria, la investigación dentro del aula, como estrategia para promover en los grupos, la motivación hacia los aprendizajes de temas como valores, moral y ética, resultó una experiencia innovadora y positiva con la cual se encontró un modo adecuado para transmitir los conocimientos teóricos pertinentes para favorecer la reflexión y revisión del propio desarrollo moral y ético del grupo participante y a la vez cumplir con los contenidos del curso. La educación moral que todos los ciudadanos y ante todo profesionales en Orientación y en Educación deben poner en práctica, requiere de analizar cuál ha sido el propio desarrollo moral del educador y de todos los actores del sistema, cuál es su comportamiento ético, así como su propia escala de valores. Ante una permanente transformación social, se hace necesario saber de dónde partir para transmitir a poblaciones juveniles y de infantes una educación moral. De esta experiencia surge un modelo de educación de calidad total que debe ser acorde con las creencias del personal y con la filosofía institucional. Consiste en combinar el currículum institucional educativo con el análisis permanente de situaciones reales, por parte de todos los actores del sistema; esto permitirá formar al educando desde un enfoque humanista con énfasis moral y ético, indispensable en una época como la actual

  1. Aversive learning of odor-heat associations in ants.

    Science.gov (United States)

    Desmedt, Lucie; Baracchi, David; Devaud, Jean-Marc; Giurfa, Martin; d'Ettorre, Patrizia

    2017-12-15

    Ants have recently emerged as useful models for the study of olfactory learning. In this framework, the development of a protocol for the appetitive conditioning of the maxilla-labium extension response (MaLER) provided the possibility of studying Pavlovian odor-food learning in a controlled environment. Here we extend these studies by introducing the first Pavlovian aversive learning protocol for harnessed ants in the laboratory. We worked with carpenter ants Camponotus aethiops and first determined the capacity of different temperatures applied to the body surface to elicit the typical aversive mandible opening response (MOR). We determined that 75°C is the optimal temperature to induce MOR and chose the hind legs as the stimulated body region because of their high sensitivity. We then studied the ability of ants to learn and remember odor-heat associations using 75°C as the unconditioned stimulus. We studied learning and short-term retention after absolute (one odor paired with heat) and differential conditioning (a punished odor versus an unpunished odor). Our results show that ants successfully learn the odor-heat association under a differential-conditioning regime and thus exhibit a conditioned MOR to the punished odor. Yet, their performance under an absolute-conditioning regime is poor. These results demonstrate that ants are capable of aversive learning and confirm previous findings about the different attentional resources solicited by differential and absolute conditioning in general. © 2017. Published by The Company of Biologists Ltd.

  2. Neuromodulation of Nestmate Recognition Decisions by Pavement Ants.

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    Andrew N Bubak

    Full Text Available Ant colonies are distributed systems that are regulated in a non-hierarchical manner. Without a central authority, individuals inform their decisions by comparing information in local cues to a set of inherent behavioral rules. Individual behavioral decisions collectively change colony behavior and lead to self-organization capable of solving complex problems such as the decision to engage in aggressive societal conflicts with neighbors. Despite the relevance to colony fitness, the mechanisms that drive individual decisions leading to cooperative behavior are not well understood. Here we show how sensory information, both tactile and chemical, and social context-isolation, nestmate interaction, or fighting non-nestmates-affects brain monoamine levels in pavement ants (Tetramorium caespitum. Our results provide evidence that changes in octopamine and serotonin in the brains of individuals are sufficient to alter the decision by pavement ants to be aggressive towards non-nestmate ants whereas increased brain levels of dopamine correlate to physical fighting. We propose a model in which the changes in brain states of many workers collectively lead to the self-organization of societal aggression between neighboring colonies of pavement ants.

  3. Los saberes cívicos en la innovación de la gestión pública

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    Freddy Mariñez-Navarro

    2016-01-01

    Full Text Available Este trabajo precisa el concepto de saberes cívicos a la luz de sus componentes tales como la inteligencia cívica, el compromiso cívico, el control social y la participación colaborativa; también el modo en que su análisis sirve para proponer un tipo de innovación participativa en la gestión pública. Mediante una exploración teórica, nos aproximamos, por una parte, a explicar los elementos de la innovación de la gestión pública participativa; y por otra, a determinar las líneas generales de encuentro en la relación complementaria entre los componentes de los saberes cívicos y la implementación de un proceso de mejora, o gestión nuevo, la introducción de un nuevo servicio o una mejora de la calidad en un servicio existente, así como las formas de proveer éstos.

  4. Effects of solar proton events on dayglow observed by the TIMED/SABER satellite

    Science.gov (United States)

    Gao, Hong; Xu, Jiyao; Smith, Anne K.; Chen, Guang-Ming

    2017-07-01

    The effect of solar proton events on the daytime O2 and OH airglows and ozone and atomic oxygen concentrations in the mesosphere is studied using data from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER). Five events occurred in September 2005, December 2006, March 2012, May 2013, and June 2015 that satisfy two criteria: the maximum proton fluxes are larger than 1000 pfu, and daytime data in the high latitude region are available from SABER. The event in December 2006 is studied in detail, and the effects of all five events are compared in brief. The results indicate that all four parameters in the mesosphere decrease during the events. During the event in 2006, the maximum depletions of O2 and OH dayglow emission rates and ozone and atomic oxygen volume mixing ratios at 70 km are respectively 31.6%, 37.0%, 42.4%, and 38.9%. The effect of the solar proton event changes with latitude, longitude, and altitude. The depletions due to the stronger events are larger on average than those due to the weaker events. The depletions of both dayglow emission rates are weaker than those of ozone and atomic oxygen. The responses of O2 and OH nightglow emissions around their peak altitudes to the SPEs are not as strong and regular as those for dayglow in the mesosphere.

  5. Sperm length evolution in the fungus-growing ants

    DEFF Research Database (Denmark)

    Baer, B.; Dijkstra, M. B.; Mueller, U. G.

    2009-01-01

    -growing ants, representing 9 of the 12 recognized genera, and mapped these onto the ant phylogeny. We show that average sperm length across species is highly variable and decreases with mature colony size in basal genera with singly mated queens, suggesting that sperm production or storage constraints affect...... the evolution of sperm length. Sperm length does not decrease further in multiply mating leaf-cutting ants, despite substantial further increases in colony size. In a combined analysis, sexual dimorphism explained 63.1% of the variance in sperm length between species. As colony size was not a significant...... predictor in this analysis, we conclude that sperm production trade-offs in males have been the major selective force affecting sperm length across the fungus-growing ants, rather than storage constraints in females. The relationship between sperm length and sexual dimorphism remained robust...

  6. The invasion biology and sociogenetics of pharaoh ants

    DEFF Research Database (Denmark)

    Schmidt, Anna Mosegaard

    Social insect colonies perform a number of tasks affecting the environments they live in. Some unintentionally introduced species have attracted the attention of scientists and general public alike when causing a number of changes to the composition and functioning of ecosystems. Such ?invaders...... laboratory lineages, thus building the foundation for future research on the species. In addition, I have started a selection experiment (still ongoing in collaboration with Dr. T. Linksvayer) using pharaoh ants, which is the first time artificial selection is attempted in an ant species. Pharaoh ants have...

  7. Desert ants learn vibration and magnetic landmarks.

    Directory of Open Access Journals (Sweden)

    Cornelia Buehlmann

    Full Text Available The desert ants Cataglyphis navigate not only by path integration but also by using visual and olfactory landmarks to pinpoint the nest entrance. Here we show that Cataglyphis noda can additionally use magnetic and vibrational landmarks as nest-defining cues. The magnetic field may typically provide directional rather than positional information, and vibrational signals so far have been shown to be involved in social behavior. Thus it remains questionable if magnetic and vibration landmarks are usually provided by the ants' habitat as nest-defining cues. However, our results point to the flexibility of the ants' navigational system, which even makes use of cues that are probably most often sensed in a different context.

  8. Population Development of Several Species of Ants on the Cocoa Trees in South Sulawesi

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    Fatahuddin Fatahuddin

    2010-08-01

    Full Text Available Several species of ants with different behavior have been found in cocoa plantations and their behavior is important to be considered because it might be correlated with the degree of protection of cocoa plant from cocoa pests. The aim of this research is to manipulate and to develop ants population in environment, so they are able to establish permanently in cocoa trees. This research was conducted in Papakaju Regions Luwu Regency in Juli to November 2009. In this study, 10 cocoa trees with ants were sampled (each species of ant in 10 cocoa trees. A control of 10 tree samples without ant was also taken. In order to assess the abundance of ant population, it was grouped based on scoring, which score 1 for less than 20 ants, score 2 for 21–50 ants, score 3 for 51–200 ants, score 4 for 201–1000 ants, and score 5 for more than 1000 per tree. The results indicated that average of population score of the three ants species reached the highest population for the Oecophylla. smaragdina with average score 4.85 (>1000 ants, Dolichoderus thoracicus, with average score 3.90 (> 200 ants and Crematogaster. difformis with average score 3.10 (>200 ants. This research indicated that three species of ants, Oecophylla smaragdina (weaver ant, Dolichoderus thoracicus (cocoa black ant and Crematogaster difformis (cracking ant. in farmer cocoa plantations in South Sulawesi giving better performance against major pests of cocoa in particular cocoa pod borer (CPB. Key words: Ant Population, Oecophylla smaragdina, Dolichoderus thoracicus, Crematogaster difformis, artificial nest, cocoa.

  9. When invasive ants meet: effects of outbreeding on queen performance in the tramp ant Cardiocondyla itsukii.

    Science.gov (United States)

    Heinze, Jürgen; Frohschammer, Sabine; Bernadou, Abel

    2017-08-18

    Most disturbed habitats in the tropics and subtropics harbor numerous species of invasive ants, and occasionally the same species has been introduced repeatedly from multiple geographical sources. We examined how experimental crossbreeding between sexuals from different populations affects the fitness of queens of the tramp ant Cardiocondyla itsukii, which is widely distributed in Asia and the Pacific Islands. Eggs laid by queens that mated with nestmate males had a higher hatching rate than eggs laid by queens mated to males from neighboring (Hawaii × Kauai) or distant introduced populations (Hawaii/Kauai × Okinawa). Furthermore, inbreeding queens had a longer lifespan and produced a less female-biased offspring sex ratio than queens from allopatric mating. This suggests that the genetic divergence between different source populations may already be so large that in case of multiple invasions eventual crossbreeding might negatively affect the fitness of tramp ants. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  10. Conflict over reproduction in an ant-plant symbiosis: why Allomerus octoarticulatus ants sterilize Cordia nodosa trees.

    Science.gov (United States)

    Frederickson, Megan E

    2009-05-01

    The evolutionary stability of mutualism is thought to depend on how well the fitness interests of partners are aligned. Because most ant-myrmecophyte mutualisms are persistent and horizontally transmitted, partners share an interest in growth but not in reproduction. Resources invested in reproduction are unavailable for growth, giving rise to a conflict of interest between partners. I investigated whether this explains why Allomerus octoarticulatus ants sterilize Cordia nodosa trees. Allomerus octoarticulatus nests in the hollow stem domatia of C. nodosa. Workers protect C. nodosa leaves against herbivores but destroy inflorescences. Using C. nodosa trees with Azteca ants, which do not sterilize their hosts, I cut inflorescences off trees to simulate sterilization by A. octoarticulatus. Sterilized C. nodosa grew faster than control trees, providing evidence for a trade-off between growth and reproduction. Allomerus octoarticulatus manipulates this trade-off to its advantage; sterilized trees produce more domatia and can house larger, more fecund colonies.

  11. Fire Ant Allergy

    Science.gov (United States)

    ... venom in a fire ant sting will kill bacteria and some of your skin cells. This results in the formation of a blister that fills with a cloudy white material in about 24 hours. While this looks like a pus-filled lesion that should be drained, ...

  12. 237. Malformación hamartomatosa de la aurícula izquierda como causa infrecuente de ataque isquémico transitorio de repetición

    Directory of Open Access Journals (Sweden)

    O. Leal

    2012-04-01

    Conclusiones: Ante la presencia de AIT, en primer lugar debemos considerar el origen cardioembólico, excluidos éstos, la patología tumoral aunque infrecuente debe tenerse en cuenta, y su tratamiento generalmente es quirúrgico.

  13. Adaptive Radiation in Socially Advanced Stem-Group Ants from the Cretaceous.

    Science.gov (United States)

    Barden, Phillip; Grimaldi, David A

    2016-02-22

    Across terrestrial ecosystems, modern ants are ubiquitous. As many as 94 out of every 100 individual arthropods in rainforests are ants, and they constitute up to 15% of animal biomass in the Amazon. Moreover, ants are pervasive agents of natural selection as over 10,000 arthropod species are specialized inquilines or myrmecomorphs living among ants or defending themselves through mimicry. Such impact is traditionally explained by sociality: ants are the first major group of ground-dwelling predatory insects to become eusocial, increasing efficiency of tasks and establishing competitive superiority over solitary species. A wealth of specimens from rich deposits of 99 million-year-old Burmese amber resolves ambiguity regarding sociality and diversity in the earliest ants. The stem-group genus Gerontoformica maintained distinct reproductive castes including morphotypes unknown in solitary aculeate (stinging) wasps, providing insight into early behavior. We present rare aggregations of workers, indicating group recruitment as well as an instance of interspecific combat; such aggression is a social feature of modern ants. Two species and an unusual new genus are described, further expanding the remarkable diversity of early ants. Stem-group ants are recovered as a paraphyletic assemblage at the base of modern lineages varying greatly in size, form, and mouthpart structure, interpreted here as an adaptive radiation. Though Cretaceous stem-group ants were eusocial and adaptively diverse, we hypothesize that their extinction resulted from the rise of competitively superior crown-group taxa that today form massive colonies, consistent with Wilson and Hölldobler's concept of "dynastic succession." Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. The genome of the fire ant Solenopsis invicta

    DEFF Research Database (Denmark)

    Wurm, Yannick; Wang, John; Riba-Grognuz, Oksana

    2011-01-01

    Ants have evolved very complex societies and are key ecosystem members. Some ants, such as the fire ant Solenopsis invicta, are also major pests. Here, we present a draft genome of S. invicta, assembled from Roche 454 and Illumina sequencing reads obtained from a focal haploid male and his brothe...

  15. Comparing temperature of subauroral mesopause over Yakutia with SABER radiometer data for 2002-2014

    Science.gov (United States)

    Ammosova, Anastasiya; Gavrilyeva, Galina; Ammosov, Petr; Koltovskoi, Igor

    2017-06-01

    We present the temperature database for the mesopause region, which was collected from spectral measurements of bands O2(0-1) and OH(6-2) with the infrared spectrograph SP-50 at the Maimaga station (63° N; 129.5° E) in 2002-2014. The temperature time series covers 11-year solar cycle. It is compared with the temperature obtained with the Sounding of the Atmosphere using Broadband Emission Radiometry instrument (SABER, v.1.07 and v.2.0), installed onboard the TIMED satellite. We compare temperatures measured during satellite passes at distances under 500 km from the intersection of the spectrograph sighting line with the hydroxyl emitting layer (~87 km) and oxygen emitting layer (~95 km). The time criterion is 30 min. We observe that there is a seasonal dependence of the difference between the ground-based and satellite measurements. The data obtained using SABER v2.0 show good agreement with the temperatures measured with the infrared digital spectrograph. The analysis we carried out allows us to conclude that a series of rotational temperatures obtained at the Maimaga station can be used to study temperature variations on different time scales including long-term trends at the mesopause height.

  16. Ant colony search algorithm for optimal reactive power optimization

    Directory of Open Access Journals (Sweden)

    Lenin K.

    2006-01-01

    Full Text Available The paper presents an (ACSA Ant colony search Algorithm for Optimal Reactive Power Optimization and voltage control of power systems. ACSA is a new co-operative agents’ approach, which is inspired by the observation of the behavior of real ant colonies on the topic of ant trial formation and foraging methods. Hence, in the ACSA a set of co-operative agents called "Ants" co-operates to find good solution for Reactive Power Optimization problem. The ACSA is applied for optimal reactive power optimization is evaluated on standard IEEE, 30, 57, 191 (practical test bus system. The proposed approach is tested and compared to genetic algorithm (GA, Adaptive Genetic Algorithm (AGA.

  17. Hierarchical modelling of line commutated power systems used in particle accelerators using Saber

    International Nuclear Information System (INIS)

    Reimund, J.A.

    1993-01-01

    This paper discusses the use of hierarchical simulation models using the program Saber trademark for the prediction of magnet ripple currents generated by the power supply/output filter combination. Modeling of an entire power system connected to output filters and particle accelerator ring magnets will be presented. Special emphasis is made on the modeling of power source imbalances caused by transformer impedance imbalances and utility variances. The affect that these imbalances have on the harmonic content of ripple current is also investigated

  18. Individual-based ant-plant networks: diurnal-nocturnal structure and species-area relationship.

    Directory of Open Access Journals (Sweden)

    Wesley Dáttilo

    Full Text Available Despite the importance and increasing knowledge of ecological networks, sampling effort and intrapopulation variation has been widely overlooked. Using continuous daily sampling of ants visiting three plant species in the Brazilian Neotropical savanna, we evaluated for the first time the topological structure over 24 h and species-area relationships (based on the number of extrafloral nectaries available in individual-based ant-plant networks. We observed that diurnal and nocturnal ant-plant networks exhibited the same pattern of interactions: a nested and non-modular pattern and an average level of network specialization. Despite the high similarity in the ants' composition between the two collection periods, ant species found in the central core of highly interacting species totally changed between diurnal and nocturnal sampling for all plant species. In other words, this "night-turnover" suggests that the ecological dynamics of these ant-plant interactions can be temporally partitioned (day and night at a small spatial scale. Thus, it is possible that in some cases processes shaping mutualistic networks formed by protective ants and plants may be underestimated by diurnal sampling alone. Moreover, we did not observe any effect of the number of extrafloral nectaries on ant richness and their foraging on such plants in any of the studied ant-plant networks. We hypothesize that competitively superior ants could monopolize individual plants and allow the coexistence of only a few other ant species, however, other alternative hypotheses are also discussed. Thus, sampling period and species-area relationship produces basic information that increases our confidence in how individual-based ant-plant networks are structured, and the need to consider nocturnal records in ant-plant network sampling design so as to decrease inappropriate inferences.

  19. Contribuições de grupos de educação em saúde para o saber de pessoas com hipertensão

    Directory of Open Access Journals (Sweden)

    Fernanda Machado da Silva

    2014-06-01

    Full Text Available Este estudo objetivou conhecer como o saber em saúde é construído por pessoas com hipertensão acompanhadas por uma equipe de saúde da família. Trata-se de uma pesquisa qualitativa, descritiva, realizada com nove pessoas, cujos dados foram coletados por meio de entrevista semiestruturada e observação. Os dados foram trabalhados com análise temática. A construção do saber em saúde é influenciada por diversos elementos do cotidiano dos sujeitos. O diálogo e a convivência com outras pessoas são elementos de maior impacto na construção desse saber. Assim, o grupo de educação em saúde foi apontado como espaço relevante, tanto pelas explicações disponibilizadas pelos profissionais, quanto pela troca de conhecimentos e experiências com os demais participantes. Conclui-se que, embora vivenciando as mesmas atividades pedagógicas, as repercussões das ações de educação em saúde serão efetivadas e percebidas diferentemente pelos sujeitos.

  20. No sex in fungus-farming ants or their crops.

    Science.gov (United States)

    Himler, Anna G; Caldera, Eric J; Baer, Boris C; Fernández-Marín, Hermógenes; Mueller, Ulrich G

    2009-07-22

    Asexual reproduction imposes evolutionary handicaps on asexual species, rendering them prone to extinction, because asexual reproduction generates novel genotypes and purges deleterious mutations at lower rates than sexual reproduction. Here, we report the first case of complete asexuality in ants, the fungus-growing ant Mycocepurus smithii, where queens reproduce asexually but workers are sterile, which is doubly enigmatic because the clonal colonies of M. smithii also depend on clonal fungi for food. Degenerate female mating anatomy, extensive field and laboratory surveys, and DNA fingerprinting implicate complete asexuality in this widespread ant species. Maternally inherited bacteria (e.g. Wolbachia, Cardinium) and the fungal cultivars can be ruled out as agents inducing asexuality. M. smithii societies of clonal females provide a unique system to test theories of parent-offspring conflict and reproductive policing in social insects. Asexuality of both ant farmer and fungal crop challenges traditional views proposing that sexual farmer ants outpace coevolving sexual crop pathogens, and thus compensate for vulnerabilities of their asexual crops. Either the double asexuality of both farmer and crop may permit the host to fully exploit advantages of asexuality for unknown reasons or frequent switching between crops (symbiont reassociation) generates novel ant-fungus combinations, which may compensate for any evolutionary handicaps of asexuality in M. smithii.

  1. Calle y Saberes en Movimiento

    Directory of Open Access Journals (Sweden)

    Laura Daniela Aguirre Aguilar

    2010-01-01

    Full Text Available En México el rezago, el ausentismo, la deserción escolar, el trabajo a temprana edad y el inicio de una vida en la calle, en repetidas ocasiones son consecuencia de un núcleo familiar desarticulado o de una débil relación intrafamiliar, así como de una condición socioeconómica en desventaja. Ante esta problemática, la Secretaría de Educación Pública, instancia gubernamental encargada de garantizar una educación de calidad para la población, trabaja coordinadamente con organizaciones de la sociedad civil e instancias públicas, para la reintegración a los espacios educativos de los niños, niñas y jóvenes en situación de calle.

  2. Em torno de Michel Foucault e Luis Buñuel: saber e poder na análise de O Discreto Charme da Burguesia

    OpenAIRE

    Priscila Canova Motta

    2014-01-01

    O objetivo desta pesquisa é analisar o filme O Discreto Charme da Burguesia, de Luis Buñuel (1972), por meio de alguns conceitos do referencial teórico-metodológico de Michel Foucault: saber e enunciado discursivo em suas relações com o poder e verdade, e buscar compreender o poder em seu exercício no filme, e não apenas em seus efeitos. Partindo de alguns princípios sobre saber em Foucault, mapeamos um enunciado fílmico que apareceu em algumas sequências, qual seja: O barulho que oculta a di...

  3. Rentabilidad de la variable activo corriente o circulante

    OpenAIRE

    Altuve, José Germán

    2014-01-01

    El activo corriente, tiene su antítesis en el pasivo corriente, mientas el segundo tiene un costo de capital u oportunidad, el primero denominado activo corriente, debe responder a la variable rentabilidad. El investigador demuestra a través del siguiente contenido, que el activo corriente, genera rentabilidad y que la misma, debe guardar proporciones por encima de la obtención del costo de oportunidad del pasivo corriente. Si afirmamos que el costo de capital de la estructu...

  4. A Theoretic Basis for IS? The Contribution of ANT

    Directory of Open Access Journals (Sweden)

    Jim Underwood

    2002-11-01

    Full Text Available Representation is a key issue of IS design and operation that is often ignored. Actor-network theory (ANT, a semiotic theory of stakeholders, provides a way of dealing with representation. Combining aspects of ANT and Foucault's discourse theory allows us to include concepts as actors and promises a flexible and durable foundation for IS practice, but ANT itself indicates that the search for a purely theoretical foundation for IS is misguided.

  5. The diversity of microorganisms associated with Acromyrmex leafcutter ants

    Directory of Open Access Journals (Sweden)

    Boomsma Jacobus J

    2002-05-01

    Full Text Available Abstract Background Molecular biological techniques are dramatically changing our view of microbial diversity in almost any environment that has so far been investigated. This study presents a systematic survey of the microbial diversity associated with a population of Acromyrmex leafcutter ants. In contrast to previous studies on social insects, which targeted specific groups of symbionts occurring in the gut (termites, Tetraponera ants or in specialised cells (Camponotus ants the objective of our present study was to do a total screening of all possible micro-organisms that can be found inside the bodies of these leafcutter ants. Results We amplified, cloned and sequenced SSU rRNA encoding gene fragments from 9 microbial groups known to have insect-associated representatives, and show that: (1 representatives of 5 out of 9 tested groups are present, (2 mostly several strains per group are present, adding up to a total of 33 different taxa. We present the microbial taxa associated with Acromymex ants in a phylogenetic context (using sequences from GenBank to assess and illustrate to which known microorganisms they are closely related. The observed microbial diversity is discussed in the light of present knowledge on the evolutionary history of Acromyrmex leafcutter ants and their known mutualistic and parasitic symbionts. Conclusions The major merits of the screening approach documented here is its high sensitivity and specificity, which allowed us to identify several microorganisms that are promising candidates for further study of their interactions with Acromyrmex leafcutter ants or their gardens.

  6. ¿Saber sin poder? El ethos universitario según los filósofos del exilio republicano español del 39

    Directory of Open Access Journals (Sweden)

    Sánchez Cue, Antolín

    2015-06-01

    Full Text Available Some relevant reflections on the University ‘ethos’ are distinguished in the context of the 1939 Spanish Republican exile. In particular, reflections of philosophers as Fernando de los Ríos, Joaquín Xirau and José Gaos, exponents of a knowledge rooted out in search of new springs of power. It is also taken into account the case of María Zambrano, whose apparent disinterest for the university question is an indication of a knowledge coherent with his exile and uncompromising to the academic discipline, of a knowledge that has resigned to power and demands a new ‘ethos’.Se apuntan algunas reflexiones relevantes sobre el ethos universitario en el contexto del exilio republicano español de 1939. En concreto, de autores como Fernando de los Ríos, Joaquín Xirau y José Gaos, exponentes todo ellos de un saber desarraigado en busca de nuevos resortes de poder. Se tiene además en cuenta el caso de María Zambrano, cuyo aparente desinterés por la cuestión universitaria es indicio de un saber coherente con su exilio e irreductible a la disciplina académica, de un saber que ha renunciado al poder y exige un nuevo ethos.

  7. Graveyards on the Move: The Spatio-Temporal Distribution of Dead Ophiocordyceps-Infected Ants

    DEFF Research Database (Denmark)

    Pontoppidan, Maj-Britt; Himaman, Winanda; Hywel-Jones, Nigel L.

    2009-01-01

    rainforest. We established that high density aggregations exist (up to 26 dead ants/m2), which we coined graveyards. We further established that graveyards are patchily distributed in a landscape with no or very few O. unilateralis-killed ants. At some, but not all, spatial scales of analysis the density...... unilateralis, which is pan-tropical in distribution, causes infected worker ants to leave their nest and die under leaves in the understory of tropical rainforests. Working in a forest dynamic plot in Southern Thailand we mapped the occurrence of these dead ants by examining every leaf in 1,360 m2 of primary...... of dead ants correlated with temperature, humidity and vegetation cover. Remarkably, having found 2243 dead ants inside graveyards we only found 2 live ants of the principal host, ant Camponotus leonardi, suggesting that foraging host ants actively avoid graveyards. We discovered that the principal host...

  8. Ants recognize foes and not friends

    Science.gov (United States)

    Guerrieri, Fernando J.; Nehring, Volker; Jørgensen, Charlotte G.; Nielsen, John; Galizia, C. Giovanni; d'Ettorre, Patrizia

    2009-01-01

    Discriminating among individuals and rejecting non-group members is essential for the evolution and stability of animal societies. Ants are good models for studying recognition mechanisms, because they are typically very efficient in discriminating ‘friends’ (nest-mates) from ‘foes’ (non-nest-mates). Recognition in ants involves multicomponent cues encoded in cuticular hydrocarbon profiles. Here, we tested whether workers of the carpenter ant Camponotus herculeanus use the presence and/or absence of cuticular hydrocarbons to discriminate between nest-mates and non-nest-mates. We supplemented the cuticular profile with synthetic hydrocarbons mixed to liquid food and then assessed behavioural responses using two different bioassays. Our results show that (i) the presence, but not the absence, of an additional hydrocarbon elicited aggression and that (ii) among the three classes of hydrocarbons tested (unbranched, mono-methylated and dimethylated alkanes; for mono-methylated alkanes, we present a new synthetic pathway), only the dimethylated alkane was effective in eliciting aggression. Our results suggest that carpenter ants use a fundamentally different mechanism for nest-mate recognition than previously thought. They do not specifically recognize nest-mates, but rather recognize and reject non-nest-mates bearing odour cues that are novel to their own colony cuticular hydrocarbon profile. This begs for a reappraisal of the mechanisms underlying recognition systems in social insects. PMID:19364750

  9. Trail Pheromone Disruption of Argentine Ant Trail Formation and Foraging

    Science.gov (United States)

    Suckling, D.M.; Peck, R.W.; Stringer, L.D.; Snook, K.; Banko, P.C.

    2010-01-01

    Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2-3 m s-1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. ?? Springer Science+Business Media, LLC 2010.

  10. Water stress strengthens mutualism among ants, trees, and scale insects.

    Directory of Open Access Journals (Sweden)

    Elizabeth G Pringle

    2013-11-01

    Full Text Available Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant-plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners' investments in a widespread ant-plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism.

  11. Water stress strengthens mutualism among ants, trees, and scale insects.

    Science.gov (United States)

    Pringle, Elizabeth G; Akçay, Erol; Raab, Ted K; Dirzo, Rodolfo; Gordon, Deborah M

    2013-11-01

    Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant-plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners' investments in a widespread ant-plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism.

  12. Ant colony algorithm for clustering in portfolio optimization

    Science.gov (United States)

    Subekti, R.; Sari, E. R.; Kusumawati, R.

    2018-03-01

    This research aims to describe portfolio optimization using clustering methods with ant colony approach. Two stock portfolios of LQ45 Indonesia is proposed based on the cluster results obtained from ant colony optimization (ACO). The first portfolio consists of assets with ant colony displacement opportunities beyond the defined probability limits of the researcher, where the weight of each asset is determined by mean-variance method. The second portfolio consists of two assets with the assumption that each asset is a cluster formed from ACO. The first portfolio has a better performance compared to the second portfolio seen from the Sharpe index.

  13. Automating ActionScript Projects with Eclipse and Ant

    CERN Document Server

    Koning, Sidney

    2011-01-01

    Automating repetitive programming tasks is easier than many Flash/AS3 developers think. With the Ant build tool, the Eclipse IDE, and this concise guide, you can set up your own "ultimate development machine" to code, compile, debug, and deploy projects faster. You'll also get started with versioning systems, such as Subversion and Git. Create a consistent workflow for multiple machines, or even complete departments, with the help of extensive Ant code samples. If you want to work smarter and take your skills to a new level, this book will get you on the road to automation-with Ant. Set up y

  14. Induced mutations in Iraqi bread wheat cv. Saber Beg

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, I F; Haidar, H O [Department of Plant Protection, Faculty of Agriculture and Biology, NRC and Agriculture Research Station, Telafor (Iraq)

    1989-07-01

    ''Saber Beg'', is a local wheat cultivar important in the semi-arid zone of Iraq where the rainfall is less than 450 mm per year. This cultivar has a good baking quality, but is of low productivity, high susceptibility to common bunt (Tilletia spp.) and to leaf rust (Puccinia recondita Rob. ex Desm.), but only in the rainy season. A mutation breeding programme using gamma irradiation has been started in 1978 to improve this cultivar. Seeds of all main tillers from M{sub 1} plants were harvested and artificially inoculated with teliospores of Tilletia spp. All the seeds from healthy M{sub 2} plants were inoculated again and sown in the same area. Out of 22920 M{sub 3} plants, 244 resistant ones were selected. During subsequent screening for 4 generations, however, only 3 mutants were confirmed.

  15. Carbohydrate supply limits invasion of natural communities by Argentine ants.

    Science.gov (United States)

    Rowles, Alexei D; Silverman, Jules

    2009-08-01

    The ability of species to invade new habitats is often limited by various biotic and physical factors or interactions between the two. Invasive ants, frequently associated with human activities, flourish in disturbed urban and agricultural environments. However, their ability to invade and establish in natural habitats is more variable. This is particularly so for the invasive Argentine ant (Linepithema humile). While biotic resistance and low soil moisture limits their invasion of natural habitats in some instances, the effect of food availability has been poorly explored. We conducted field experiments to determine if resource availability limits the spread and persistence of Argentine ants in remnant natural forest in North Carolina. Replicated transects paired with and without sucrose solution feeding stations were run from invaded urban edges into forest remnants and compared over time using baits and direct counts at feeding stations. Repeated under different timing regimes in 2006 and 2007, access to sucrose increased local Argentine ant abundances (1.6-2.5 fold) and facilitated their progression into the forest up to 73 +/- 21% of 50-m transects. Resource removal caused an expected decrease in Argentine ant densities in 2006, in conjunction with their retreat to the urban/forest boundary. However, in 2007, Argentine ant numbers unexpectedly continued to increase in the absence of sugar stations, possibly through access to alternative resources or conditions not available the previous year such as honeydew-excreting Hemiptera. Our results showed that supplementing carbohydrate supply facilitates invasion of natural habitat by Argentine ants. This is particularly evident where Argentine ants continued to thrive following sugar station removal.

  16. Exotic ants (Hymenoptera, Formicidae) of Ohio

    OpenAIRE

    Ivanov,Kal

    2016-01-01

    The worldwide transfer of plants and animals outside their native ranges is an ever increasing problem for global biodiversity. Ants are no exception and many species have been transported to new locations often with profound negative impacts on local biota. The current study is based on data gathered since the publication of the “Ants of Ohio” in 2005. Here I expand on our knowledge of Ohio’s myrmecofauna by contributing new records, new distributional information and natural history notes. ...

  17. Individual Rules for Trail Pattern Formation in Argentine Ants (Linepithema humile)

    OpenAIRE

    Perna, Andrea; Granovskiy, Boris; Garnier, Simon; Nicolis, Stamatios C.; Labédan, Marjorie; Theraulaz, Guy; Fourcassié, Vincent; Sumpter, David J. T.

    2012-01-01

    We studied the formation of trail patterns by Argentine ants exploring an empty arena. Using a novel imaging and analysis technique we estimated pheromone concentrations at all spatial positions in the experimental arena and at different times. Then we derived the response function of individual ants to pheromone concentrations by looking at correlations between concentrations and changes in speed or direction of the ants. Ants were found to turn in response to local pheromone concentrations,...

  18. Ant-mediated effects on spruce litter decomposition, solution chemistry, and microbial activity

    DEFF Research Database (Denmark)

    Stadler, B.; Schramm, Andreas; Kalbitz, K.

    2006-01-01

    the effects of ants and aphid honeydew on litter solution of Norway spruce, microbial enzyme activities, and needle decomposition in a field and greenhouse experiment during summer 2003. In the field, low ant densities had relatively little effects on litter solution 30 cm away from a tree trunk...... and %N were not affected by ants or honeydew. Our results suggest that ants have a distinct and immediate effect on solution composition and microbial activity in the litter layer indicating accelerated litter decay whereas the effect of honeydew was insignificant. Keywords: Ants; Decomposition; Formica......Forest management practices often generate clear-cut patches, which may be colonized by ants not present in the same densities in mature forests. In addition to the associated changes in abiotic conditions ants can initiate processes, which do not occur in old-growth stands. Here, we analyse...

  19. Ants: Major Functional Elements in Fruit Agro-Ecosystems and Biological Control Agents

    Directory of Open Access Journals (Sweden)

    Lamine Diamé

    2017-12-01

    Full Text Available Ants are a very diverse taxonomic group. They display remarkable social organization that has enabled them to be ubiquitous throughout the world. They make up approximately 10% of the world’s animal biomass. Ants provide ecosystem services in agrosystems by playing a major role in plant pollination, soil bioturbation, bioindication, and the regulation of crop-damaging insects. Over recent decades, there have been numerous studies in ant ecology and the focus on tree cropping systems has given added importance to ant ecology knowledge. The only missing point in this knowledge is the reasons underlying difference between the positive and negative effects of ants in tree cropping systems. This review article provides an overview of knowledge of the roles played by ants in orchards as functional elements, and on the potential of Oecophylla weaver ants as biological control agents. It also shows the potential and relevance of using ants as an agro-ecological diagnosis tool in orchards. Lastly, it demonstrates the potential elements which may determine the divergent negative and positive of their effects on cropping systems.

  20. Economy of scale: third partner strengthens a keystone ant-plant mutualism.

    Science.gov (United States)

    Prior, Kirsten M; Palmer, Todd M

    2018-02-01

    While foundation species can stabilize ecosystems at landscape scales, their ability to persist is often underlain by keystone interactions occurring at smaller scales. Acacia drepanolobium is a foundation tree, comprising >95% of woody cover in East African black-cotton savanna ecosystems. Its dominance is underlain by a keystone mutualistic interaction with several symbiotic ant species in which it provides housing (swollen thorns) and carbohydrate-rich nectar from extra-floral nectaries (EFN). In return, it gains protection from catastrophic damage from mega-herbivores. Crematogaster mimosae is the ecologically dominant symbiotic ant in this system, also providing the highest protection services. In addition to tending EFN, C. mimosae tend scale insects for carbohydrate-rich honeydew. We investigated the role of scale insects in this specialized ant-plant interaction. Specifically, does this putatively redundant third partner strengthen the ant-plant mutualism by making the ant a better protector of the tree? Or does it weaken the mutualism by being costly to the tree while providing no additional benefit to the ant-plant mutualism? We coupled observational surveys with two scale-manipulation experiments and found evidence that this third partner strengthens the ant-plant mutualism. Trees with scale insects experimentally removed experienced a 2.5X increase in elephant damage compared to trees with scale insects present over 10 months. Reduced protection was driven by scale removal causing a decrease in ant colony size and per capita baseline activity and defensive behavior. We also found that ants increased scale-tending and the density of scale insects on trees when EFN were experimentally reduced. Thus, in this system, scale insects and EFN are likely complementary, rather than redundant, resources with scale insects benefitting ants when EFN production is low (such as during annual dry periods in this semi-arid ecosystem). This study reveals that a third

  1. An invasive slug exploits an ant-seed dispersal mutualism.

    Science.gov (United States)

    Meadley Dunphy, Shannon A; Prior, Kirsten M; Frederickson, Megan E

    2016-05-01

    Plant-animal mutualisms, such as seed dispersal, are often vulnerable to disruption by invasive species. Here, we show for the first time how a non-ant invasive species negatively affects seed dispersal by ants. We examined the effects of several animal species that co-occur in a temperate deciduous forest-including native and invasive seed-dispersing ants (Aphaenogaster rudis and Myrmica rubra, respectively), an invasive slug (Arion subfuscus), and native rodents-on a native myrmecochorous plant, Asarum canadense. We experimentally manipulated ant, slug, and rodent access to seed depots and measured seed removal. We also video-recorded depots to determine which other taxa interact with seeds. We found that A. rudis was the main disperser of seeds and that A. subfuscus consumed elaiosomes without dispersing seeds. Rodent visitation was rare, and rodent exclusion had no significant effect on seed or elaiosome removal. We then used data obtained from laboratory and field mesocosm experiments to determine how elaiosome robbing by A. subfuscus affects seed dispersal by A. rudis and M. rubra. We found that elaiosome robbing by slugs reduced seed dispersal by ants, especially in mesocosms with A. rudis, which picks up seeds more slowly than M. rubra. Taken together, our results show that elaiosome robbing by an invasive slug reduces seed dispersal by ants, suggesting that invasive slugs can have profound negative effects on seed dispersal mutualisms.

  2. Olfactory memory established during trophallaxis affects food search behaviour in ants

    OpenAIRE

    Provecho, Y.; Josens, R.

    2009-01-01

    Camponotus mus ants can associate sucrose and odour at the source during successive foraging cycles and use this memory to locate the nectar in the absence of other cues. These ants perform conspicuous trophallactic behaviour during recruitment while foraging for nectar. In this work, we studied whether Camponotus mus ants are able to establish this odour-sucrose association in the social context of trophallaxis and we evaluated this memory in another context previously experienced by the ant...

  3. Plant genotype shapes ant-aphid interactions: implications for community structure and indirect plant defense.

    Science.gov (United States)

    Mooney, Kailen A; Agrawal, Anurag A

    2008-06-01

    Little is known about the mechanisms by which plant genotype shapes arthropod community structure. In a field experiment, we measured the effects of milkweed (Asclepias syriaca) genotype and ants on milkweed arthropods. Populations of the ant-tended aphid Aphis asclepiadis and the untended aphid Myzocallis asclepiadis varied eight- to 18-fold among milkweed genotypes, depending on aphid species and whether ants were present. There was no milkweed effect on predatory arthropods. Ants increased Aphis abundance 59%, decreased Myzocallis abundance 52%, and decreased predator abundance 56%. Milkweed genotype indirectly influenced ants via direct effects on Aphis and Myzocallis abundance. Milkweed genotype also modified ant-aphid interactions, influencing the number of ants attracted per Aphis and Myzocallis. While ant effects on Myzocallis were consistently negative, effects on Aphis ranged from antagonistic to mutualistic among milkweed genotypes. As a consequence of milkweed effects on ant-aphid interactions, ant abundance varied 13-fold among milkweed genotypes, and monarch caterpillar survival was negatively correlated with genetic variation in ant abundance. We speculate that heritable variation in milkweed phloem sap drives these effects on aphids, ants, and caterpillars. In summary, milkweed exerts genetic control over the interactions between aphids and an ant that provides defense against foliage-feeding caterpillars.

  4. Commentary: Warring ants

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Biosciences; Volume 27; Issue 2. Commentary: Warring ants: Lessons from Lanchester's laws of combat? Renee M Borges. Volume 27 Issue 2 March 2002 pp 75-78. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/jbsc/027/02/0075-0078 ...

  5. Individual Rules for Trail Pattern Formation in Argentine Ants (Linepithema humile)

    Science.gov (United States)

    Perna, Andrea; Granovskiy, Boris; Garnier, Simon; Nicolis, Stamatios C.; Labédan, Marjorie; Theraulaz, Guy; Fourcassié, Vincent; Sumpter, David J. T.

    2012-01-01

    We studied the formation of trail patterns by Argentine ants exploring an empty arena. Using a novel imaging and analysis technique we estimated pheromone concentrations at all spatial positions in the experimental arena and at different times. Then we derived the response function of individual ants to pheromone concentrations by looking at correlations between concentrations and changes in speed or direction of the ants. Ants were found to turn in response to local pheromone concentrations, while their speed was largely unaffected by these concentrations. Ants did not integrate pheromone concentrations over time, with the concentration of pheromone in a 1 cm radius in front of the ant determining the turning angle. The response to pheromone was found to follow a Weber's Law, such that the difference between quantities of pheromone on the two sides of the ant divided by their sum determines the magnitude of the turning angle. This proportional response is in apparent contradiction with the well-established non-linear choice function used in the literature to model the results of binary bridge experiments in ant colonies (Deneubourg et al. 1990). However, agent based simulations implementing the Weber's Law response function led to the formation of trails and reproduced results reported in the literature. We show analytically that a sigmoidal response, analogous to that in the classical Deneubourg model for collective decision making, can be derived from the individual Weber-type response to pheromone concentrations that we have established in our experiments when directional noise around the preferred direction of movement of the ants is assumed. PMID:22829756

  6. Individual rules for trail pattern formation in Argentine ants (Linepithema humile.

    Directory of Open Access Journals (Sweden)

    Andrea Perna

    Full Text Available We studied the formation of trail patterns by Argentine ants exploring an empty arena. Using a novel imaging and analysis technique we estimated pheromone concentrations at all spatial positions in the experimental arena and at different times. Then we derived the response function of individual ants to pheromone concentrations by looking at correlations between concentrations and changes in speed or direction of the ants. Ants were found to turn in response to local pheromone concentrations, while their speed was largely unaffected by these concentrations. Ants did not integrate pheromone concentrations over time, with the concentration of pheromone in a 1 cm radius in front of the ant determining the turning angle. The response to pheromone was found to follow a Weber's Law, such that the difference between quantities of pheromone on the two sides of the ant divided by their sum determines the magnitude of the turning angle. This proportional response is in apparent contradiction with the well-established non-linear choice function used in the literature to model the results of binary bridge experiments in ant colonies (Deneubourg et al. 1990. However, agent based simulations implementing the Weber's Law response function led to the formation of trails and reproduced results reported in the literature. We show analytically that a sigmoidal response, analogous to that in the classical Deneubourg model for collective decision making, can be derived from the individual Weber-type response to pheromone concentrations that we have established in our experiments when directional noise around the preferred direction of movement of the ants is assumed.

  7. Molecular structure and diversity of PBAN/Pyrokinin family peptides in ants

    Directory of Open Access Journals (Sweden)

    Man-Yeon eChoi

    2012-02-01

    Full Text Available Neuropeptides are the largest group of insect hormones. They are produced in the central and peripheral nervous systems and affect insect development, reproduction, feeding and behavior. A variety of neuropeptide families have been identified in insects. One of these families is the PBAN/pyrokinin family defined by a common FXPRLamide or similar amino acid fragment at the C-terminal end. These peptides, found in all insects studied thus far, have been conserved throughout evolution. The most well studied physiological function is regulation of moth sex pheromone biosynthesis through the Pheromone Biosynthesis Activating Neurohormone (PBAN, although several developmental functions have also been reported. Over the past years we have extended knowledge of the PBAN/pyrokinin family of peptides to ants, focusing mainly on the fire ant, Solenopsis invicta. The fire ant is one of the most studied social insects and over the last 60 years a great deal has been learned about many aspects of this ant, including the behaviors and chemistry of pheromone communication. However, virtually nothing is known about the regulation of these pheromone systems. Recently, we demonstrated the presence of PBAN/pyrokinin immunoreactive neurons in the fire ant, and identified and characterized PBAN and additional neuropeptides. We have mapped the fire ant PBAN gene structure and determined the tissue expression level in the central nervous system of the ant. We review here our research to date on the molecular structure and diversity of ant PBAN/pyrokinin peptides in preparation for determining the function of the neuropeptides in ants and other social insects.

  8. Ultrastructure of antennal sensillae of the samsum ant ...

    African Journals Online (AJOL)

    Black ant (Samsum), Pachycodyla sennarrensis, stings and injects venom and inflicts allergy (a rare clinical problem) due to its local and systemic reaction, which is considered as a health hazard amongst Saudi society. Thus, black ant is a source of serious concern for the government and experts as well.

  9. The effect of diet and opponent size on aggressive interactions involving caribbean crazy ants (Nylanderia fulva.

    Directory of Open Access Journals (Sweden)

    Katherine C Horn

    Full Text Available Biotic interactions are often important in the establishment and spread of invasive species. In particular, competition between introduced and native species can strongly influence the distribution and spread of exotic species and in some cases competition among introduced species can be important. The Caribbean crazy ant, Nylanderia fulva, was recently introduced to the Gulf Coast of Texas, and appears to be spreading inland. It has been hypothesized that competition with the red imported fire ant, Solenopsis invicta, may be an important factor in the spread of crazy ants. We investigated the potential of interspecific competition among these two introduced ants by measuring interspecific aggression between Caribbean crazy ant workers and workers of Solenopsis invicta. Specifically, we examined the effect of body size and diet on individual-level aggressive interactions among crazy ant workers and fire ants. We found that differences in diet did not alter interactions between crazy ant workers from different nests, but carbohydrate level did play an important role in antagonistic interactions with fire ants: crazy ants on low sugar diets were more aggressive and less likely to be killed in aggressive encounters with fire ants. We found that large fire ants engaged in fewer fights with crazy ants than small fire ants, but fire ant size affected neither fire ant nor crazy ant mortality. Overall, crazy ants experienced higher mortality than fire ants after aggressive encounters. Our findings suggest that fire ant workers might outcompete crazy ant workers on an individual level, providing some biotic resistance to crazy ant range expansion. However, this resistance may be overcome by crazy ants that have a restricted sugar intake, which may occur when crazy ants are excluded from resources by fire ants.

  10. Weaver Ants to Control Fruit Fly Damage to Tanzanian Mangoes

    DEFF Research Database (Denmark)

    Kirkegaard, Nina

    in Australia and West Africa. In this study, small scale farmers did not think weaver ants protected their mangoes from fruit flies. Observational studies confirmed the farmers’ views. No volatile compounds, likely to be responsible for the weaver ants’ deterrent effect, were identified. This study focused...... mangoes varied a lot with zero infestation in some fruits and more than 100 pupae emerging from other fruits, indicating that other factors than the presence of weaver ants affect the fruit flies’ decision on where to oviposit. It was not uncommon for farmers to place newly harvested mangoes below mango...... not shown to be effectively deterring fruit flies, there is no great motivation for farmers to adopt weaver ants. Assuming the weaver ants could be managed in a way that made weaver ants deter fruit flies effectively there are still some economic aspects which should be studied further. It is necessary...

  11. Advances in Research on the Venom Chemistry of Imported Fire Ants

    Science.gov (United States)

    Workers of the imported fire ants, including red imported fire ants, Solenopsis invicta Buren, black imported fire ants, S. richteri Forel, and their hybrid (S. invicta × S. richteri), are vicious stingers. Since the venomous sting is a significant medical problem to humans, the chemistry of import...

  12. Descolonização do corpo e mobilidade humana: mulheres imigrantes e a produção de saberes contra a violência obstétrica

    Directory of Open Access Journals (Sweden)

    Lya Amanda Rossa

    2017-12-01

    Full Text Available O fenômeno da mobilidade humana implica não apenas no deslocamento de idiomas, recursos e culturas, mas sobretudo, no movimento de corpos e a troca de saberes e modos de fazer e compreender a vida em seus diferentes ciclos. Assim, os modos de gestar e nascer são transportados e transformados durante o processo. A construção epistemológica de saberes descolonizados não deve ser alheia a uma construção sobre os corpos e seus ciclos, especialmente quanto ao corpo feminino, que foi e permanece, em muitos espaços, contido e medicalizado. O presente trabalho pretende analisar como mobilização de mulheres imigrantes  na cidade de São Paulo contribui para o questionamento e a construção de novos saberes sobre maternidade, parto e gestação, reunindo mulheres imigrantes e brasileiras contra a violência obstétrica.

  13. Comparing different methods to assess weaver ant abundance in plantation trees

    DEFF Research Database (Denmark)

    Wargui, Rosine; Offenberg, Joachim; Sinzogan, Antonio

    2015-01-01

    Weaver ants (Oecophylla spp.) are widely used as effective biological control agents. In order to optimize their use, ant abundance needs to be tracked. As several methods have been used to estimate ant abundance on plantation trees, abundances are not comparable between studies and no guideline...... is available on which method to apply in a particular study. This study compared four existing methods: three methods based on the number of ant trails on the main branches of a tree (called the Peng 1, Peng 2 and Offenberg index) and one method based on the number of ant nests per tree. Branch indices did...... not produce equal scores and cannot be compared directly. The Peng 1 index was the fastest to assess, but showed only limited seasonal fluctuations when ant abundance was high, because it approached its upper limit. The Peng 2 and Offenberg indices were lower and not close to the upper limit and therefore...

  14. Bases históricas de la conciencia teórica sobre el edificio y su expresión en "Los diez libros de arquitectura" de Vitruvio

    OpenAIRE

    Ludeña Urquizo, Wiley Hermilio; Ludeña Urquizo, Wiley Hermilio; Ludeña Urquizo, Wiley Hermilio

    1990-01-01

    Hasta antes de la revolución Ilustrada del siglo XVIII, aquello que occidente convino en denominar como el campo de la arquitectura, se constituía de un solo saber» Un saber que aglutinaba en sí al mismo tiempo a los conocimientos sobre el diseño y sus requerimientos, sobre los métodos y las técnicas constructivas, sobre los valores de la edificación, así como sobre los aspectos filosófico-conceptuales de la práctica edificatoria. Todos estos conocimientos formaban parte de un solo cuerpo cog...

  15. Various chemical strategies to deceive ants in three Arhopala species (lepidoptera: Lycaenidae exploiting Macaranga myrmecophytes.

    Directory of Open Access Journals (Sweden)

    Yoko Inui

    Full Text Available Macaranga myrmecophytes (ant-plants are generally well protected from herbivore attacks by their symbiotic ants (plant-ants. However, larvae of Arhopala (Lepidoptera: Lycaenidae species survive and develop on specific Macaranga ant-plant species without being attacked by the plant-ants of their host species. We hypothesized that Arhopala larvae chemically mimic or camouflage themselves with the ants on their host plant so that the larvae are accepted by the plant-ant species of their host. Chemical analyses of cuticular hydrocarbons showed that chemical congruency varied among Arhopala species; A. dajagaka matched well the host plant-ants, A. amphimuta did not match, and unexpectedly, A. zylda lacked hydrocarbons. Behaviorally, the larvae and dummies coated with cuticular chemicals of A. dajagaka were well attended by the plant-ants, especially by those of the host. A. amphimuta was often attacked by all plant-ants except for the host plant-ants toward the larvae, and those of A. zylda were ignored by all plant-ants. Our results suggested that conspicuous variations exist in the chemical strategies used by the myrmecophilous butterflies that allow them to avoid ant attack and be accepted by the plant-ant colonies.

  16. Cercomacra and related antbirds (Aves, Formicariidae as army ant followers

    Directory of Open Access Journals (Sweden)

    Edwin O. Willis

    1984-01-01

    Full Text Available Cercomacra and Schistocichla antbirds (Formicariidae favor dense foliage and seldom follow army ants for flushed prey, since the ants move through open forest understory as well as through dense zones. Two other lineages, the Drymophila-Hypocnemis lineage (of dense woodland understory and the Formicivora lineage (of dense bushes in dry or semiopen zones, also cannot follow ants regularly through open forest understory.

  17. Saberes locales campesinos sobre el alimento: aportes a la soberanía y la salud mental comunitaria

    Directory of Open Access Journals (Sweden)

    Beatriz E. Arias L.

    2016-06-01

    Full Text Available Introducción: Los trabajos sobre violencia política, salud mental y vida cotidiana realizados en alianza entre la academia y una organización campesina en Antioquia, han llevado a posicionar la soberanía alimentaria como un asunto central en procesos de recuperación y reparación colectiva, en un contexto donde se amalgama el sufrimiento, la precarización del modo de vida campesino y la deuda histórica de una reforma agraria inacabada Objetivo: Explorar los procesos salutogénicos que emergen de las acciones reflexivas emprendidas por un grupo de mujeres campesinas a partir de su participación en una experiencia de Investigación Acción Participativa (IAP y sus aportes a la soberanía alimentaria local. Metodología: Estudio cualitativo que recoge elementos de la IAP, desarrollado en Argelia, Oriente antioqueño, a través de entrevistas semiestructuradas, grupos focales, observación participante y ejercicios de cartografía social, además de acciones de incidencia local Resultados: Se describen los productos derivados del proceso de investigar-actuar-participar tales como la consolidación de un equipo local de investigación y tres acciones de incidencia en la vida local: inventario de semillas nativas y criollas, vivero comunitario, feria campesina y festival gastronómico. Conclusiones: 1 El alimento adquiere una connotación política y trasciende lo nutricional funcional. 2 Los saberes locales de subsistencia/resistencia generan soberanía 3 Las redes sociales sobre las que se soportan los saberes, y los saberes mismos, son recursos sociales de salud. 4 Es necesario problematizar las medidas técnicas convencionales en el campo de la salud mental y ubicar su campo de acción en el terreno de las relaciones microsociales.

  18. Plan de acción tutorial en los centros docentes universitarios: el rol del profesor tutor

    Directory of Open Access Journals (Sweden)

    Luis SOBRADO FERNÁNDEZ

    2008-01-01

    Full Text Available La integración de la Universidad española en el Espacio Europeo de Educación Superior conlleva una serie de desafíos en los que un adecuado enfoque debe repercutir en la necesaria mejora de la calidad de la docencia, la investigación y la gestión universitaria. En esta nueva perspectiva la función tutorial debe ocupar un puesto preeminente para poder profundizar, adecuadamente, en la transmisión y creación de los saberes como eje de la actividad docente en el desarrollo personal de los estudiantes y, también, para posibilitar en éstos los procesos de transición académica y profesional. El profesor tutor, en el escenario universitario, debe ayudar a los estudiantes a determinar y diseñar sus objetivos personales, académicos y profesionales. En esta proyección innovadora, el Plan de Acción Tutorial en los centros docentes universitarios puede ser un recurso de gran significado y valor.

  19. Uni-directional trail sharing by two species of ants a Monte Carlo study

    International Nuclear Information System (INIS)

    Kunduraci, T; Kayacan, O

    2015-01-01

    We study insect traffic, specifically ant traffic on a uni-directional trail which is shared by two species of ants, one of which is ‘good’ at smelling and the other ‘poor’. The two distinct species of ants are placed mixed on the same trail and individuals of both are permitted to make a U-turn when they encounter another ant in front of them. The theoretical scheme for the ant traffic is based on an asymmetric simple exclusion model. The ant traffic on the uni-directional trail is studied as a function of the number of ‘good-smelling’ ants and the evaporation probability of pheromones by keeping the number of ‘poor-smelling ants’ constant during Monte Carlo simulations. (paper)

  20. Improving Emergency Management by Modeling Ant Colonies

    Science.gov (United States)

    2015-03-01

    perform functions such as nursing the brood or maintaining the nest. The more mature workers will begin to travel outside the nest to perform foraging...small sized ants predominantly act in functional roles such as nurses or transport services within the nest. The larger sizes predominantly function...stages: the founding stage, the ergonomic stage, and the reproductive stage. The founding stage is marked by a queen ant successful mating and laying

  1. An Analysis of the Acquisition Process for Simplified Acquisition of Base Engineering Requirements (SABER) Contracts and Its Potential Impact on Contractor Performance

    National Research Council Canada - National Science Library

    Heaps, Brian

    2001-01-01

    The Simplified Acquisition of Base Engineering Requirements (SABER) contract's main purpose is to expedite contract award of civil engineer requirements through the issuance of individual delivery orders...

  2. Revolutionizing Remote Exploration with ANTS

    Science.gov (United States)

    Clark, P. E.; Rilee, M. L.; Curtis, S.; Truszkowski, W.

    2002-05-01

    We are developing the Autonomous Nano-Technology Swarm (ANTS) architecture based on an insect colony analogue for the cost-effective, efficient, systematic survey of remote or inaccessible areas with multiple object targets, including planetary surface, marine, airborne, and space environments. The mission context is the exploration in the 2020s of the most compelling remaining targets in the solar system: main belt asteroids. Main belt asteroids harbor important clues to Solar System origins and evolution which are central to NASA's goals in Space Science. Asteroids are smaller than planets, but their number is far greater, and their combined surface area likely dwarfs the Earth's. An asteroid survey will dramatically increase our understanding of the local resources available for the Human Exploration and Development of Space. During the mission composition, shape, gravity, and orbit parameters could be returned to Earth for perhaps several thousand asteroids. A survey of this area will rival the great explorations that encircled this globe, opened up the New World, and laid the groundwork for the progress and challenges of the last centuries. The ANTS architecture for a main belt survey consists of a swarm of as many as a thousand or more highly specialized pico-spacecraft that form teams to survey as many as one hundred asteroids a month. Multi-level autonomy is critical for ANTS and the objective of the proposed study is to work through the implications and constraints this entails. ANTS couples biologically inspired autonomic control for basic functions to higher level artificial intelligence that together enable individual spacecraft to operate as specialized, cooperative, social agents. This revolutionary approach postulates highly advanced, but familiar, components integrated and operated in a way that uniquely transcends any evolutionary extrapolation of existing trends and enables thousand-spacecraft missions.

  3. TÉCNICAS, SABERES E PRÁTICAS PSICOLÓGICAS NA PRIMEIRA REPÚBLICA (1889-1930

    Directory of Open Access Journals (Sweden)

    Alexandre de Carvalho Castro

    2018-04-01

    Full Text Available O objetivo deste estudo foi analisar as técnicas, saberes e práticas tidas como psicológicas no Rio de Janeiro da Primeira República (1889-1930. Nesse sentido, pautou-se por uma metodologia que priorizou o levantamento de fontes bibliográficas primárias (artigos, livros e relatórios técnicos de época. Constatou-se, como resultado da pesquisa empreendida, que ocorreram aproximações e convergências entre áreas da psicologia aplicada que, posteriormente, iriam ocupar institucionalmente espaços bem separados. Assim, verificou-se que a designação de dado saber, prática ou técnica configurada como "Psicologia" não foi sempre configurada em áreas de aplicação independentes. Nessa perspectiva, segue uma linha diversa de abordagens históricas que primam por setorizar práticas psicológicas, sendo a principal contribuição do artigo para o campo da história da psicologia justamente a de mostrar que uma eventual “História da Psicologia do Trabalho”, no período investigado, não era absolutamente distinta de áreas, hoje classificadas, como as da “História da Psicologia Clínica”, ou da “História da Psicologia Escolar”.

  4. Development of a Geomagnetic Storm Correction to the International Reference Ionosphere E-Region Electron Densities Using TIMED/SABER Observations

    Science.gov (United States)

    Mertens, C. J.; Xu, X.; Fernandez, J. R.; Bilitza, D.; Russell, J. M., III; Mlynczak, M. G.

    2009-01-01

    Auroral infrared emission observed from the TIMED/SABER broadband 4.3 micron channel is used to develop an empirical geomagnetic storm correction to the International Reference Ionosphere (IRI) E-region electron densities. The observation-based proxy used to develop the storm model is SABER-derived NO+(v) 4.3 micron volume emission rates (VER). A correction factor is defined as the ratio of storm-time NO+(v) 4.3 micron VER to a quiet-time climatological averaged NO+(v) 4.3 micron VER, which is linearly fit to available geomagnetic activity indices. The initial version of the E-region storm model, called STORM-E, is most applicable within the auroral oval region. The STORM-E predictions of E-region electron densities are compared to incoherent scatter radar electron density measurements during the Halloween 2003 storm events. Future STORM-E updates will extend the model outside the auroral oval.

  5. Urban habitat complexity affects species richness but not environmental filtering of morphologically-diverse ants

    Directory of Open Access Journals (Sweden)

    Alessandro Ossola

    2015-10-01

    Full Text Available Habitat complexity is a major determinant of structure and diversity of ant assemblages. Following the size-grain hypothesis, smaller ant species are likely to be advantaged in more complex habitats compared to larger species. Habitat complexity can act as an environmental filter based on species size and morphological traits, therefore affecting the overall structure and diversity of ant assemblages. In natural and semi-natural ecosystems, habitat complexity is principally regulated by ecological successions or disturbance such as fire and grazing. Urban ecosystems provide an opportunity to test relationships between habitat, ant assemblage structure and ant traits using novel combinations of habitat complexity generated and sustained by human management. We sampled ant assemblages in low-complexity and high-complexity parks, and high-complexity woodland remnants, hypothesizing that (i ant abundance and species richness would be higher in high-complexity urban habitats, (ii ant assemblages would differ between low- and high-complexity habitats and (iii ants living in high-complexity habitats would be smaller than those living in low-complexity habitats. Contrary to our hypothesis, ant species richness was higher in low-complexity habitats compared to high-complexity habitats. Overall, ant assemblages were significantly different among the habitat complexity types investigated, although ant size and morphology remained the same. Habitat complexity appears to affect the structure of ant assemblages in urban ecosystems as previously observed in natural and semi-natural ecosystems. However, the habitat complexity filter does not seem to be linked to ant morphological traits related to body size.

  6. Urban habitat complexity affects species richness but not environmental filtering of morphologically-diverse ants

    Science.gov (United States)

    Nash, Michael A.; Christie, Fiona J.; Hahs, Amy K.; Livesley, Stephen J.

    2015-01-01

    Habitat complexity is a major determinant of structure and diversity of ant assemblages. Following the size-grain hypothesis, smaller ant species are likely to be advantaged in more complex habitats compared to larger species. Habitat complexity can act as an environmental filter based on species size and morphological traits, therefore affecting the overall structure and diversity of ant assemblages. In natural and semi-natural ecosystems, habitat complexity is principally regulated by ecological successions or disturbance such as fire and grazing. Urban ecosystems provide an opportunity to test relationships between habitat, ant assemblage structure and ant traits using novel combinations of habitat complexity generated and sustained by human management. We sampled ant assemblages in low-complexity and high-complexity parks, and high-complexity woodland remnants, hypothesizing that (i) ant abundance and species richness would be higher in high-complexity urban habitats, (ii) ant assemblages would differ between low- and high-complexity habitats and (iii) ants living in high-complexity habitats would be smaller than those living in low-complexity habitats. Contrary to our hypothesis, ant species richness was higher in low-complexity habitats compared to high-complexity habitats. Overall, ant assemblages were significantly different among the habitat complexity types investigated, although ant size and morphology remained the same. Habitat complexity appears to affect the structure of ant assemblages in urban ecosystems as previously observed in natural and semi-natural ecosystems. However, the habitat complexity filter does not seem to be linked to ant morphological traits related to body size. PMID:26528416

  7. Species-Specific Effects of Ant Inhabitants on Bromeliad Nutrition.

    Directory of Open Access Journals (Sweden)

    Ana Z Gonçalves

    Full Text Available Predator activities may lead to the accumulation of nutrients in specific areas of terrestrial habitats where they dispose of prey carcasses. In their feeding sites, predators may increase nutrient availability in the soil and favor plant nutrition and growth. However, the translocation of nutrients from one habitat to another may depend on predator identity and diet, as well as on the amount of prey intake. Here we used isotopic (15N and physiological methods in greenhouse experiments to evaluate the effects of the identity of predatory ants (i.e., the consumption of prey and nest sites on the nutrition and growth of the bromeliad Quesnelia arvensis. We showed that predatory ants with protein-based nutrition (i.e., Odontomachus hastatus, Gnamptogenys moelleri improved the performance of their host bromeliads (i.e., increased foliar N, production of soluble proteins and growth. On the other hand, the contribution of Camponotus crassus for the nutritional status of bromeliads did not differ from bromeliads without ants, possibly because this ant does not have arthropod prey as a preferred food source. Our results show, for the first time, that predatory ants can translocate nutrients from one habitat to another within forests, accumulating nutrients in their feeding sites that become available to bromeliads. Additionally, we highlight that ant contribution to plant nutrition may depend on predator identity and its dietary requirements. Nest debris may be especially important for epiphytic and terrestrial bromeliads in nutrient-poor environments.

  8. New fossil ants in French Cretaceous amber (Hymenoptera: Formicidae)

    Science.gov (United States)

    Perrichot, Vincent; Nel, André; Néraudeau, Didier; Lacau, Sébastien; Guyot, Thierry

    2008-02-01

    Recent studies on the ant phylogeny are mainly based on the molecular analyses of extant subfamilies and do not include the extinct, only Cretaceous subfamily Sphecomyrminae. However, the latter is of major importance for ant relationships, as it is considered the most basal subfamily. Therefore, each new discovery of a Mesozoic ant is of high interest for improving our understanding of their early history and basal relationships. In this paper, a new sphecomyrmine ant, allied to the Burmese amber genus Haidomyrmex, is described from mid-Cretaceous amber of France as Haidomyrmodes mammuthus gen. and sp. n. The diagnosis of the tribe Haidomyrmecini is emended based on the new type material, which includes a gyne (alate female) and two incomplete workers. The genus Sphecomyrmodes, hitherto known by a single species from Burmese amber, is also reported and a new species described as S. occidentalis sp. n. after two workers remarkably preserved in a single piece of Early Cenomanian French amber. The new fossils provide additional information on early ant diversity and relationships and demonstrate that the monophyly of the Sphecomyrminae, as currently defined, is still weakly supported.

  9. Inter-Hemispheric Coupling During Northern Polar Summer Periods of 2002-2010 using TIMED/SABER Measurements

    Science.gov (United States)

    Goldberg, Richard A.; Feofilov, A. G.; Pesnell, W. D.; Kutepov, A. A.

    2012-01-01

    It has been found that for more than one polar summer season between 2002-2010, the northern polar mesospheric region near and above about 80 km was warmer than normal. The strongest warming effect of this type was observed to occur during northern summer 2002. Theoretical studies have implied that these "anomalies" were preceded by unusual dynamical processes in the southern hemisphere. We have analyzed temperature distributions measured by the SABER limb scanning infrared radiometer aboard the NASA TIMED satellite between 2002-2010 at altitudes from 15 to 110 km and for latitudes between 83 S to 83 N. We describe the approach to trace the inter-hemispheric temperature correlations demonstrating the global features that were unique for the "anomalous" northern polar summers. From our analysis of SABER data from 2002-2010, the anomalous heating for the northern mesopause region during northern summer was accompanied by stratospheric heating in the equatorial region. In the winter hemisphere it is accompanied by heating in the lower stratosphere and mesopause region, and cooling in the stratopause region. Also, all the elements of the temperature anomaly structure appear to develop and fade away nearly simultaneously, thereby suggesting either a global influence or a rapid exchange.

  10. Ants farm subterranean aphids mostly in single clone groups

    DEFF Research Database (Denmark)

    Ivens, Aniek B.F.; Kronauer, Daniel Jan Christoph; Pen, Ido

    2012-01-01

    mutualisms have been studied in sufficient genetic detail to address these issues, so we decided to characterize symbiont diversity in the complex mutualism between multiple root aphid species and Lasius flavus ants. After showing elsewhere that three of these aphid species have low dispersal and mostly...... if not exclusively asexual reproduction, we here investigate aphid diversity within and between ant nest mounds. Results The three focal species (Geoica utricularia, Forda marginata and Tetraneura ulmi) had considerable clonal diversity at the population level. Yet more than half of the ant mounds contained just....... The ants appear to eat most of the early instar aphids, so that adult aphids are unlikely to face limited phloem resources and scramble competition with other aphids. We suggest that such culling of carbohydrate-providing symbionts for protein ingestion may maintain maximal host yield per aphid while also...

  11. Novel fungal disease in complex leaf-cutting ant societies

    DEFF Research Database (Denmark)

    Hughes, David Peter; Evans, Harry C.; Hywel-Jones, Nigel

    2009-01-01

    1. The leaf-cutting ants practise an advanced system of mycophagy where they grow a fungus as a food source. As a consequence of parasite threats to their crops, they have evolved a system of morphological, behavioural, and chemical defences, particularly against fungal pathogens (mycopathogens). 2....... Specific fungal diseases of the leaf-cutting ants themselves have not been described, possibly because broad spectrum anti-fungal defences against mycopathogens have reduced their susceptibility to entomopathogens. 3. Using morphological and molecular tools, the present study documents three rare infection...... events of Acromyrmex and Atta leaf-cutting ants by Ophiocordyceps fungi, agenus of entomopathogens that is normally highly specific in its host choice. 4. As leaf-cutting ants have been intensively studied, the absence of prior records of Ophiocordyceps suggests that these infections may be a novel event...

  12. Operant conditioning in the ant Myrmica sabuleti.

    Science.gov (United States)

    Cammaerts, M C

    2004-11-30

    Operant conditioning could be obtained in the ant Myrmica sabuleti by presenting to the workers, during a six-day period, an apparatus containing either sugared water or meat as a reward. The conditioning obtained using sugared water as a reward was short lasting. A reconditioning was more persistent and lasted four hours. The ants' response was very precise, since they exhibited it only in front of an apparatus identical to that used during the training phase. Operant conditioning obtained using meat as a reward was more pronounced than that obtained by using sugared water, probably because meat is more valuable as a reward than sugar for the species studied, which is essentially a carnivorous one. Such a conditioning was rather persistent. Indeed, a first operant conditioning obtained by using meat as a reward could still be detected after seven hours, and a reconditioning was still significant after eight hours. One day after this eight-hour period without rewarding the ants, the response was higher again and a further day later, it was still significant. Since the operant conditioning is easy to perform and quantify and since the ants' response is very precise, such a conditioning can be used for further studying M. sabuleti workers' visual perception.

  13. Aspectos a tener en cuenta antes de aplicar una antibioticoterapia Aspects to be taken into account before applying an antibiotic therapy

    Directory of Open Access Journals (Sweden)

    Moisés Morejón García

    2005-04-01

    Full Text Available Se presenta una revisión sobre los aspectos que debe tener en cuenta el facultativo antes de aplicar una antibioticoterapia, como son: la procedencia del paciente, la localización y el tipo de la sepsis, los factores del huésped, la determinación del germen posible, la selección del antibiótico, la vía de administración y sus dosis e intervalos, la duración del tratamiento antimicrobiano, los efectos adversos y el costo del medicamento. Además se abordan las combinaciones de antimicrobianos, la quimioprofilaxis antimicrobiana y el uso inadecuado de los antimicrobianos.A review of the aspects the physician should take into consideration before applying an antibiotic therapy is made. The origin of the patient, the location and type of sepsis, the factors of the guest, the determination of the possible germ, the selection of the antibiotic, the route of administration and its doses and intervals, the duration of the antimicrobial treatment, the adverse effects and the cost of the drug are among these aspects. The combination of antimicrobials, the antimicrobial chemoprophylaxis and the inadequate use of antimicrobials are also exposed.

  14. Ant parasite queens revert to mating singly

    DEFF Research Database (Denmark)

    Sumner, Seirian; Hughes, William Owen Hamar; Pedersen, Jes Søe

    2004-01-01

    quantified and they tend to be similar in related species. Here we compare the mating strategies of the leaf-cutting ant Acromyrmex echinatior and its recently derived social parasite Acromyrmex insinuator, which is also its closest relative 2 (see Fig. 1 ). We find that although the host queens mate with up......A parasitic ant has abandoned the multiple mating habit of the queens of its related host. Multiple mating (polyandry) is widespread among animal groups, particularly insects 1 . But the factors that maintain it and underlie its evolution are hard to verify because benefits and costs are not easily...... to a dozen different males, the social parasite mates only singly. This rapid and surprising reversion to single mating in a socially parasitic ant indicates that the costs of polyandry are probably specific to a free-living lifestyle....

  15. The worldwide expansion of the Argentine ant

    DEFF Research Database (Denmark)

    Vogel, Valerie; Pedersen, Jes Søe; Giraud, Tatiana

    2010-01-01

    Aim The aim of this study was to determine the number of successful establishments of the invasive Argentine ant outside native range and to see whether introduced supercolonies have resulted from single or multiple introductions. We also compared the genetic diversity of native versus introduced...... supercolonies to assess the size of the propagules (i.e. the number of founding individuals) at the origin of the introduced supercolonies. Location Global. Methods We used mitochondrial DNA (mtDNA) markers and microsatellite loci to study 39 supercolonies of the Argentine ant Linepithema humile covering both......) and secondary introductions (from sites with established invasive supercolonies) were important in the global expansion of the Argentine ant. In combination with the similar social organization of colonies in the native and introduced range, this indicates that invasiveness did not evolve recently as a unique...

  16. Saberes mapuche en la relación del hombre con la naturaleza: aportes para

    OpenAIRE

    Carlos Manuel Pacheco Huaiquifil; Sonia Osses Bustingorry

    2015-01-01

    El presente artículo tiene como objetivo elaborar una propuesta educativa de educación ambiental basada en los saberes ancestrales mapuche relacionados con el cuidado medioambiental.El estudio de tipo cualitativo,utiliza la Teoría Fundamentada. Se aplicaron 12 entrevistas a personas con ascendencia mapuche y que vive no han vivido en comunidades mapuche o sectores rurales. Los resultados identifican un con junto de conocimientos de cuidado y daño medioambiental y estrategias de enseñanza que ...

  17. Urban physiology: city ants possess high heat tolerance.

    Directory of Open Access Journals (Sweden)

    Michael J Angilletta

    Full Text Available Urbanization has caused regional increases in temperature that exceed those measured on a global scale, leading to urban heat islands as much as 12 degrees C hotter than their surroundings. Optimality models predict ectotherms in urban areas should tolerate heat better and cold worse than ectotherms in rural areas. We tested these predications by measuring heat and cold tolerances of leaf-cutter ants from South America's largest city (São Paulo, Brazil. Specifically, we compared thermal tolerances of ants from inside and outside of the city. Knock-down resistance and chill-coma recovery were used as indicators of heat and cold tolerances, respectively. Ants from within the city took 20% longer to lose mobility at 42 degrees C than ants from outside the city. Interestingly, greater heat tolerance came at no obvious expense of cold tolerance; hence, our observations only partially support current theory. Our results indicate that thermal tolerances of some organisms can respond to rapid changes in climate. Predictive models should account for acclimatory and evolutionary responses during climate change.

  18. Extrafloral nectar fuels ant life in deserts

    OpenAIRE

    Aranda-Rickert, Adriana; Diez, Patricia; Marazzi, Brigitte

    2014-01-01

    Interactions mediated by extrafloral nectary (EFN)-bearing plants that reward ants with a sweet liquid secretion are well documented in temperate and tropical habitats. However, their distribution and abundance in deserts are poorly known. In this study, we test the predictions that biotic interactions between EFN plants and ants are abundant and common also in arid communities and that EFNs are only functional when new vegetative and reproductive structures are developing. In a seasonal dese...

  19. Antígonas. Una visión intertextual

    Directory of Open Access Journals (Sweden)

    Elena Cano Turrión

    2011-04-01

    Full Text Available In this article and from an intertextual point of view, we will try to examine how theSophoclean hypotext has generated three very different hypertexts. The first one is the short story“Antígona o la elección” by M. Yourcenar, which goes further the religious motivation in the originaltext; then, there is an essay written as a dialogue by Maria Zambrano, entitled La tumba de Antígonawhich main topics are confrontation against power, lack of freedom and destiny and faith in humanconscience. Finally, Luis Riaza’s Antígona…¡Cerda! Appears closer to its hypotext but at the same timesemantic deviation becomes more relevant.

  20. Reaction of mutualistic and granivorous ants to ulex elaiosome chemicals.

    Science.gov (United States)

    Gammans, Nicola; Bullock, James M; Gibbons, Hannah; Schönrogge, Karsten

    2006-09-01

    It has been proposed that chemicals on plant elaiosomes aid seed detection by seed-dispersing ants. We hypothesized that the chemical interaction between ants and elaiosomes is more intimate than a generic attraction, and that elaiosome chemicals will attract mutualistic but not granivorous ant species. We investigated this by using two gorse species, Ulex minor and U. europaeus, and two associated ant species from European heathlands, the mutualist Myrmica ruginodis and the granivore Tetramorium caespitum. Behavioral studies were conducted with laboratory nests and foraging arenas. Both ants will take Ulex seeds, but while M. ruginodis showed increased antennation toward ether extracts of elaiosome surface chemicals compared with controls, T. caespitum showed no response. Elaiosome extracts were separated into seven lipid fractions. M. ruginodis showed increased antennation only toward the diglyceride fractions of both Ulex species, whereas T. caespitum showed no consistent reaction. This indicates that M. ruginodis can detect the elaiosome by responding to its surface chemicals, but T. caespitum is unresponsive to these chemicals. Responses to surface chemicals could increase the rate of seed detection in the field, and so these results suggest that Ulex elaiosomes produce chemicals that facilitate attraction of mutualistic rather than granivorous ant species. This could reduce seed predation and increase Ulex fitness.

  1. [Syagrus romanzoffiana (Arecaceae) seed utilization by ants in a secondary forest in South Brazil].

    Science.gov (United States)

    Silva, Fernanda R; Begnini, Romualdo M; Klier, Vinícius A; Scherer, Karla Z; Lopes, Benedito C; Castellani, Tânia T

    2009-01-01

    Ants can nest in a wide variety of substracts. This paper shows Syagrus romanzoffiana seed utilization by ants in an Atlantic secondary forest. We report 29 seeds occupied by small-bodied ants, with 27 of them showing at least two ant development stages. Although a large number of seeds were sampled, a low level of ant occupation was observed.

  2. Recognition of social identity in ants

    Directory of Open Access Journals (Sweden)

    Nick eBos

    2012-03-01

    Full Text Available Recognizing the identity of others, from the individual to the group level, is a hallmark of society. Ants, and other social insects, have evolved advanced societies characterized by efficient social recognition systems. Colony identity is mediated by colony specific signature mixtures, a blend of hydrocarbons present on the cuticle of every individual (the label. Recognition occurs when an ant encounters another individual, and compares the label it perceives to an internal representation of its own colony odor (the template. A mismatch between label and template leads to rejection of the encountered individual. Although advances have been made in our understanding of how the label is produced and acquired, contradictory evidence exists about information processing of recognition cues. Here, we review the literature on template acquisition in ants and address how and when the template is formed, where in the nervous system it is localized, and the possible role of learning. We combine seemingly contradictory evidence in to a novel, parsimonious theory for the information processing of nestmate recognition cues.

  3. In vitro studies of ante-mortem proliferation kinetics

    International Nuclear Information System (INIS)

    McBride, W.H.; Withers, H.R.

    1986-01-01

    Using K562 human erythroblastoid cells, it was concluded that dose fractionation has no discrepant effect on the ante-mortem proliferation kinetics of doomed cells as opposed to clonogenic cell survival and that effects on ante-mortem proliferation kinetics cannot be solely responsible for the differences in fractionation response between early and late responding tissues. (UK)

  4. Bacteria may contribute to distant species recognition in ant-aphid mutualistic relationships.

    Science.gov (United States)

    Fischer, Christophe Y; Detrain, Claire; Thonart, Philippe; Haubruge, Eric; Francis, Frédéric; Verheggen, François J; Lognay, Georges C

    2017-04-01

    Mutualistic interactions between ant and aphid species have been the subject of considerable historical and contemporary investigations, the primary benefits being cleaning and protection for the aphids and carbohydrate-rich honeydew for the ants. Questions remained, however, as to the volatile semiochemical factor influencing this relationship. A recent study highlighted the role of bacterial honeydew volatile compounds in ant attraction. Here, ant's ability to distantly discriminate 2 aphid species was investigated based on bacterial honeydew semiochemicals emissions using a two-way olfactometer. Both the mutualistic aphid Aphis fabae L. and the nonmyrmecophilous aphid Acyrthosiphon pisum Harris were found to be attractive for the ant Lasius niger L. The level of attraction was similar in both assays (control vs. one of the aphid species). However, when given a choice between these 2 aphid species, ants showed a significant preference for Aphis fabae. Honeydew volatiles, mostly from bacterial origins, are known to be a key element in ant attraction. Using the same olfactometry protocol, the relative attractiveness of volatiles emitted by honeydews collected from each aphid species and by bacteria isolated from each honeydew was investigated. Again, ants significantly preferred volatiles released by Aphis fabae honeydew and bacteria. This information suggests that microbial honeydew volatiles enable ants to distantly discriminate aphid species. These results strengthen the interest of studying the occurrence and potential impact of microorganisms in insect symbioses. © 2015 Institute of Zoology, Chinese Academy of Sciences.

  5. Targeted removal of ant colonies in ecological experiments, using hot water.

    Science.gov (United States)

    Tschinkel, Walter R; King, Joshua R

    2007-01-01

    Ecological experiments on fire ants cannot, or should not, use poison baits to eliminate the fire ants because such baits are not specific to fire ants, or even to ants. Hot water is an extremely effective and specific killing agent for fire ant colonies, but producing large amounts of hot water in the field, and making the production apparatus mobile have been problematical. The construction and use of a charcoal-fired kiln made from a 55-gal. oil drum lined with a sand-fireclay mixture is described. An automobile heater fan powered from a 12-v battery provided a draft. Dual bilge pumps pumped water from a large tank through a long coil of copper tubing within the kiln to produce 4 to 5 l. of hot water per min. The hot water was collected in 20 l. buckets and poured into fire ant nests previously opened by piercing with a stick. The entire assembly was transported in and operated from the back of a pickup truck. Five experimental plots containing 32 to 38 colonies of the fire ant, Solenopsis invicta, Buren (Hymenoptera: Formicidae), were treated with hot water over a period of two years. All colonies on the treatment plots were treated twice with hot water early in 2004, reducing their numbers to zero. However new colonies were formed, and mature colonies expanded into the plots. A third treatment was made in the spring of 2005, after which fire ant populations were suppressed for over a year. Whereas the 5 control plots contained a total of 166 mostly large colonies, the 5 treatment plots contained no live colonies at all. Averaged over a two-year period, a 70% reduction in total number of colonies was achieved (P ants.

  6. The genomic impact of 100 million years of social evolution in seven ant species

    DEFF Research Database (Denmark)

    Gadau, Jürgen; Helmkampf, Martin; Nygaard, Sanne

    2012-01-01

    Ants (Hymenoptera, Formicidae) represent one of the most successful eusocial taxa in terms of both their geographic distribution and species number. The publication of seven ant genomes within the past year was a quantum leap for socio- and ant genomics. The diversity of social organization in ants...... between social and solitary insects, as well as among ant species. Altogether, these seven ant genomes open exciting new research avenues and opportunities for understanding the genetic basis and regulation of social species, and adaptive complex systems in general....... makes them excellent model organisms to study the evolution of social systems. Comparing the ant genomes with those of the honeybee, a lineage that evolved eusociality independently from ants, and solitary insects suggests that there are significant differences in key aspects of genome organization...

  7. Two castes sizes of leafcutter ants in task partitioning in foraging activity

    Directory of Open Access Journals (Sweden)

    Marcelo Arruda de Toledo

    Full Text Available ABSTRACT: Task partitioning in eusocial animals is most likely an evolutionary adaptation that optimizes the efficiency of the colony to grow and reproduce. It was investigated indirect task partitioning in two castes sizes; this involves task partitioning in which the material transported is not transferred directly from one individual to another, but where it is dropped by one ant to be picked up by another. In two separate approaches, it was confirmed previous results pertaining to leaf caching activities among Atta colombica with task partitioning activities involving leaf dropping among Atta sexdens rubropilosa , in which there is a correlation between the size of an individual ant and the leaf fragment it transports. It was also suggested that this correlation exists only in individual ants that cut and transport (CaT the same fragment to the nest. When task partitioning occurs and individual ants transporting (T leaf fragments cut by other ants, the correlation becomes looser or disappears. We also observed that CaT ants are smaller than T ants.

  8. Infection of army ant pupae by two new parasitoid mites (Mesostigmata: Uropodina

    Directory of Open Access Journals (Sweden)

    Adrian Brückner

    2017-10-01

    Full Text Available A great variety of parasites and parasitoids exploit ant societies. Among them are the Mesostigmata mites, a particularly common and diverse group of ant-associated arthropods. While parasitism is ubiquitous in Mesostigmata, parasitoidism has only been described in the genus Macrodinychus. Yet information about the basic biology of most Macrodinychus species is lacking. Out of 24 formally described species, information about basic life-history traits is only available for three species. Here we formally describe two new Macrodinychus species, i.e. Macrodinychus hilpertae and Macrodinychus derbyensis. In both species, immature stages developed as ecto-parasitoids on ant pupae of the South-East Asian army ant Leptogenys distinguenda. By piercing the developing ant with their chelicera, the mites apparently suck ant hemolymph, ultimately killing host individuals. We compare infection rates among all studied Macrodinychus species and discuss possible host countermeasures against parasitoidism. The cryptic lifestyle of living inside ant nests has certainly hampered the scientific discovery of Macrodinychus mites and we expect that many more macrodinychid species await scientific discovery and description.

  9. Infection of army ant pupae by two new parasitoid mites (Mesostigmata: Uropodina).

    Science.gov (United States)

    Brückner, Adrian; Klompen, Hans; Bruce, Andrew Iain; Hashim, Rosli; von Beeren, Christoph

    2017-01-01

    A great variety of parasites and parasitoids exploit ant societies. Among them are the Mesostigmata mites, a particularly common and diverse group of ant-associated arthropods. While parasitism is ubiquitous in Mesostigmata, parasitoidism has only been described in the genus Macrodinychus . Yet information about the basic biology of most Macrodinychus species is lacking. Out of 24 formally described species, information about basic life-history traits is only available for three species. Here we formally describe two new Macrodinychus species, i.e. Macrodinychus hilpertae and Macrodinychus derbyensis . In both species, immature stages developed as ecto-parasitoids on ant pupae of the South-East Asian army ant Leptogenys distinguenda . By piercing the developing ant with their chelicera, the mites apparently suck ant hemolymph, ultimately killing host individuals. We compare infection rates among all studied Macrodinychus species and discuss possible host countermeasures against parasitoidism. The cryptic lifestyle of living inside ant nests has certainly hampered the scientific discovery of Macrodinychus mites and we expect that many more macrodinychid species await scientific discovery and description.

  10. Evidences that human disturbance simplify the ant fauna associated a Stachytarpheta glabra Cham. (Verbenaceae compromising the benefits of ant-plant mutualism

    Directory of Open Access Journals (Sweden)

    BC. Barbosa

    Full Text Available Interaction among species, like ants and plants through extrafloral nectaries (EFNs, are important components of ecological communities’ evolution. However, the effect of human disturbance on such specific interactions and its ecological consequences is poorly understood. This study evaluated the outcomes of mutualism between ants and the EFN-bearing plant Stachytarpheta glabra under anthropogenic disturbance. We compared the arthropod fauna composition between two groups of twenty plant individuals, one in an area disturbed by human activities and one in a preserved area. We also check the plant investment in herbivory defense and the consequential leaf damage by herbivore. Our results indicate that such disturbances cause simplification of the associated fauna and lack of proper ant mutualist. This led to four times more herbivory on plants of disturbed areas, despite the equal amount of EFN and ant visitors and low abundance of herbivores. The high pressure of herbivory may difficult the re-establishment of S. glabra, an important pioneer species in ferruginous fields, therefore it may affect resilience of this fragile ecological community.

  11. Olfactory memory established during trophallaxis affects food search behaviour in ants.

    Science.gov (United States)

    Provecho, Yael; Josens, Roxana

    2009-10-01

    Camponotus mus ants can associate sucrose and odour at the source during successive foraging cycles and use this memory to locate the nectar in the absence of other cues. These ants perform conspicuous trophallactic behaviour during recruitment while foraging for nectar. In this work, we studied whether Camponotus mus ants are able to establish this odour-sucrose association in the social context of trophallaxis and we evaluated this memory in another context previously experienced by the ant, as a nectar source. After a single trophallaxis of a scented solution, the receiver ant was tested in a Y-maze without any reward, where two scents were presented: in one arm, the solution scent and in the other, a new scent. Ants consistently chose the arm with the solution scent and stayed longer therein. Trophallaxis duration had no effect on the arm choice or with the time spent in each arm. Workers are able to associate an odour (conditioned stimulus) with the sucrose (unconditioned stimulus) they receive through a social interaction and use this memory as choice criteria during food searching.

  12. USING ANT COMMUNITIES FOR RAPID ASSESSMENT OF TERRESTRIAL ECOSYSTEM HEALTH

    Energy Technology Data Exchange (ETDEWEB)

    Wike, L; Doug Martin, D; Michael Paller, M; Eric Nelson, E

    2007-01-12

    Ecosystem health with its near infinite number of variables is difficult to measure, and there are many opinions as to which variables are most important, most easily measured, and most robust, Bioassessment avoids the controversy of choosing which physical and chemical parameters to measure because it uses responses of a community of organisms that integrate all aspects of the system in question. A variety of bioassessment methods have been successfully applied to aquatic ecosystems using fish and macroinvertebrate communities. Terrestrial biotic index methods are less developed than those for aquatic systems and we are seeking to address this problem here. This study had as its objective to examine the baseline differences in ant communities at different seral stages from clear cut back to mature pine plantation as a precursor to developing a bioassessment protocol. Comparative sampling was conducted at four seral stages; clearcut, 5 year, 15 year and mature pine plantation stands. Soil and vegetation data were collected at each site. All ants collected were preserved in 70% ethyl alcohol and identified to genus. Analysis of the ant data indicates that ants respond strongly to the habitat changes that accompany ecological succession in managed pine forests and that individual genera as well as ant community structure can be used as an indicator of successional change. Ants exhibited relatively high diversity in both early and mature seral stages. High ant diversity in the mature seral stages was likely related to conditions on the forest floor which favored litter dwelling and cool climate specialists.

  13. Novel Phialophora species from leaf-cutting ants (tribe Attini)

    NARCIS (Netherlands)

    Attili-Angelis, D.; Duarte, A.P.M.; Pagnocca, F.C.; Nagamoto, N.S.; de Vries, M.; Stielow, J.B.; de Hoog, G.S.

    2014-01-01

    Ants in the tribe Attini (Hymenoptera, Formicidae) maintain a 50 million-year-old lifestyle of co-evolution with symbiotic basidiomycetous fungi which they cultivate as essential source of nutrition. However, other microorganisms have been reported from ant habitats indicating a higher diversity of

  14. Why do house-hunting ants recruit in both directions?

    NARCIS (Netherlands)

    Planqué, R.; Dechaume-Moncharmont, F.-X.; Franks, N.R.; Kovacs, T.; Marshall, J.A.R.

    2007-01-01

    To perform tasks, organisms often use multiple procedures. Explaining the breadth of such behavioural repertoires is not always straightforward. During house hunting, colonies of Temnothorax albipennis ants use a range of behaviours to organise their emigrations. In particular, the ants use tandem

  15. AntBot: Anti-pollution peer-to-peer botnets

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Guanhua [Los Alamos National Laboratory; Eidenbenz, Stephan [Los Alamos National Laboratory; Ha, Duc T [UNIV. AT BUFFALO

    2009-01-01

    Botnets, which are responsible for many email sparnming and DDoS (Distributed Denial of Service) attacks in the current Internet, have emerged as one of most severe cyber-threats in recent years. To evade detection and improve resistance against countermeasures, botnets have evolved from the first generation that relies on IRC chat channels to deliver commands to the current generation that uses highly resilient P2P (Peer-to-Peer) protocols to spread their C&C (Command and Control) information. It is, however, revealed that P2P botnets, although relieved from the single point of failure that IRC botnets suffer, can be easily disrupted using pollution-based mitigation schemes [15]. In this paper, we play the devil's advocate and propose a new type of hypothetical botnets called AntBot, which aim to propagate their C&C information to individual bots even though there exists an adversary that persistently pollutes keys used by seized bots to search the command information. The key idea of AntBot is a tree-like structure that bots use to deliver the command so that captured bots reveal only limited information. To evaluate effectiveness of AntBot against pollution-based mitigation in a virtual environment, we develop a distributed P2P botnet simulator. Using extensive experiments, we demonstrate that AntBot operates resiliently against pollution-based mitigation. We further present a few potential defense schemes that could effectively disrupt AntBot operations.

  16. Intrapopulation differences in ant eating in the mountain gorillas of Bwindi Impenetrable National Park, Uganda.

    Science.gov (United States)

    Ganas, Jessica; Robbins, Martha M

    2004-10-01

    Variability in ant eating has been observed in several populations of eastern and western gorillas. We investigated the occurrence of ant (Dorylus sp.) eating in two groups of mountain gorillas (Gorilla beringei beringei) with overlapping home ranges within Bwindi Impenetrable National Park, Uganda from September 2001 to August 2002. We calculated the frequency of ant eating by an indirect method of analyzing fecal samples from silverbacks, adult females, and juveniles. One group consumed ants significantly more often than the other (3.3 vs 17.6% of days sampled). Furthermore, the group that consumed ants more often also consumed them on a seasonal basis (September-February monthly range: 0-8%; March-August monthly range: 30-42.9%). Finally, females and juveniles of this group consumed ants significantly more often than did the silverback (total samples containing ants: silverback, 2.1%; adult female, 13.2%; juvenile, 11.2%). Differences in ant eating between groups are likely due to variability in use of habitats where ants occur (particularly secondary forests). Surveys of ant densities in differing habitats, nutritional analysis of ants, and quantification of the amount of ants in their diets are necessary to understand if ant consumption is due to availability, nutritional value, group traditions, or taste preference.

  17. Seasonal dynamics of ant community structure in the Moroccan Argan Forest.

    Science.gov (United States)

    El Keroumi, Abderrahim; Naamani, Khalid; Soummane, Hassna; Dahbi, Abdallah

    2012-01-01

    In this study we describe the structure and composition of ant communities in the endemic Moroccan Argan forest, using pitfall traps sampling technique throughout the four seasons between May 2006 and February 2007. The study focused on two distinct climatic habitats within the Essaouira Argan forest, a semi-continental site at Lahssinate, and a coastal site at Boutazarte. Thirteen different ant species were identified, belonging to seven genera. Monomorium subopacum Smith and Tapinoma simrothi Krausse-Heldrungen (Hymenoptera: Formicidae) were the most abundant and behaviorally dominant ant species in the arganeraie. In addition, more specimens were captured in the semi-continental site than in the coastal area. However, no significant difference was observed in species richness, evenness, or diversity between both sites. Composition and community structure showed clear seasonal dynamics. The number of species, their abundance, their diversity, and their evenness per Argan tree were significantly dissimilar among seasons. The richness (except between summer and autumn), and the abundance and the evenness of ant species among communities, showed a significant difference between the dry period (summer and spring) and the rainy period (winter and autumn). Higher abundance and richness values occurred in the dry period of the year. Ant species dominance and seasonal climatic variations in the arganeraie might be among the main factors affecting the composition, structure, and foraging activity of ant communities. This study, together with recent findings on ant predation behavior below Argan trees, highlights the promising use of dominant ant species as potential agents of Mediterranean fruit fly bio-control in the Argan forest and surrounding ecosystems.

  18. Trail pheromone of the Argentine ant, Linepithema humile (Mayr (Hymenoptera: Formicidae.

    Directory of Open Access Journals (Sweden)

    Dong-Hwan Choe

    Full Text Available The Argentine ant (Linepithema humile is recognized as one of the world's most damaging invasive species. One reason for the ecological dominance of introduced Argentine ant populations is their ability to dominate food and habitat resources through the rapid mobilization and recruitment of thousands of workers. More than 30 years ago, studies showed that (Z-9-hexadecenal strongly attracted Argentine ant workers in a multi-choice olfactometer, suggesting that (Z-9-hexadecenal might be the trail pheromone, or a component of a trail pheromone mixture. Since then, numerous studies have considered (Z-9-hexadecenal as the key component of the Argentine ant trails. Here, we report the first chemical analyses of the trails laid by living Argentine ants and find that (Z-9-hexadecenal is not present in a detectible quantity. Instead, two iridoids, dolichodial and iridomyrmecin, appear to be the primary chemical constituents of the trails. Laboratory choice tests confirmed that Argentine ants were attracted to artificial trails comprised of these two chemicals significantly more often than control trails. Although (Z-9-hexadecenal was not detected in natural trails, supplementation of artificial dolichodial+iridomyrmecin trails with an extremely low concentraion of (Z-9-hexadecenal did increase the efficacy of the trail-following behavior. In stark contrast with previous dogma, our study suggests that dolichodial and iridomyrmecin are major components of the Argentine ant trail pheromone. (Z-9-hexadecenal may act in an additive manner with these iridoids, but it does not occur in detectable quantities in Argentine ant recruitment trails.

  19. The effects of ant nests on soil fertility and plant performance: a meta-analysis.

    Science.gov (United States)

    Farji-Brener, Alejandro G; Werenkraut, Victoria

    2017-07-01

    Ants are recognized as one of the major sources of soil disturbance world-wide. However, this view is largely based on isolated studies and qualitative reviews. Here, for the first time, we quantitatively determined whether ant nests affect soil fertility and plant performance, and identified the possible sources of variation of these effects. Using Bayesian mixed-models meta-analysis, we tested the hypotheses that ant effects on soil fertility and plant performance depend on the substrate sampled, ant feeding type, latitude, habitat and the plant response variable measured. Ant nests showed higher nutrient and cation content than adjacent non-nest soil samples, but similar pH. Nutrient content was higher in ant refuse materials than in nest soils. The fertilizer effect of ant nests was also higher in dry habitats than in grasslands or savannas. Cation content was higher in nests of plant-feeding ants than in nests of omnivorous species, and lower in nests from agro-ecosystems than in nests from any other habitat. Plants showed higher green/root biomass and fitness on ant nests soils than in adjacent, non-nest sites; but plant density and diversity were unaffected by the presence of ant nests. Root growth was particularly higher in refuse materials than in ant nest soils, in leaf-cutting ant nests and in deserts habitats. Our results confirm the major role of ant nests in influencing soil fertility and vegetation patterns and provide information about the factors that mediate these effects. First, ant nests improve soil fertility mainly through the accumulation of refuse materials. Thus, different refuse dump locations (external or in underground nest chambers) could benefit different vegetation life-forms. Second, ant nests could increase plant diversity at larger spatial scales only if the identity of favoured plants changes along environmental gradients (i.e. enhancing β-diversity). Third, ant species that feed on plants play a relevant role fertilizing soils

  20. Specialized Fungal Parasites and Opportunistic Fungi in Gardens of Attine Ants

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    Fernando C. Pagnocca

    2012-01-01

    Full Text Available Ants in the tribe Attini (Hymenoptera: Formicidae comprise about 230 described species that share the same characteristic: all coevolved in an ancient mutualism with basidiomycetous fungi cultivated for food. In this paper we focused on fungi other than the mutualistic cultivar and their roles in the attine ant symbiosis. Specialized fungal parasites in the genus Escovopsis negatively impact the fungus gardens. Many fungal parasites may have small impacts on the ants' fungal colony when the colony is balanced, but then may opportunistically shift to having large impacts if the ants' colony becomes unbalanced.

  1. Ant-caterpillar antagonism at the community level: interhabitat variation of tritrophic interactions in a neotropical savanna.

    Science.gov (United States)

    Sendoya, Sebastián F; Oliveira, Paulo S

    2015-03-01

    Ant foraging on foliage can substantially affect how phytophagous insects use host plants and represents a high predation risk for caterpillars, which are important folivores. Ant-plant-herbivore interactions are especially pervasive in cerrado savanna due to continuous ant visitation to liquid food sources on foliage (extrafloral nectaries, insect honeydew). While searching for liquid rewards on plants, aggressive ants frequently attack or kill insect herbivores, decreasing their numbers. Because ants vary in diet and aggressiveness, their effect on herbivores also varies. Additionally, the differential occurrence of ant attractants (plant and insect exudates) on foliage produces variable levels of ant foraging within local floras and among localities. Here, we investigate how variation of ant communities and of traits among host plant species (presence or absence of ant attractants) can change the effect of carnivores (predatory ants) on herbivore communities (caterpillars) in a cerrado savanna landscape. We sampled caterpillars and foliage-foraging ants in four cerrado localities (70-460 km apart). We found that: (i) caterpillar infestation was negatively related with ant visitation to plants; (ii) this relationship depended on local ant abundance and species composition, and on local preference by ants for plants with liquid attractants; (iii) this was not related to local plant richness or plant size; (iv) the relationship between the presence of ant attractants and caterpillar abundance varied among sites from negative to neutral; and (v) caterpillars feeding on plants with ant attractants are more resistant to ant predation than those feeding on plants lacking attractants. Liquid food on foliage mediates host plant quality for lepidopterans by promoting generalized ant-caterpillar antagonism. Our study in cerrado shows that the negative effects of generalist predatory ants on herbivores are detectable at a community level, affecting patterns of abundance and

  2. Myrmeciza and related antbirds (Aves, Formicariidae as army ant followers

    Directory of Open Access Journals (Sweden)

    Edwin O. Willis

    1984-01-01

    Full Text Available Antbirds of the genera Myrmeciza (including Sipia and Myrmoborus, Gymnocichla, and Sclateria hop near or on the ground in fairly dense vegetation, "pounding" their tails downward. Where dense understory vegetation is widespread and ants move in it for long distances, certain of these antbirds become regular ant followers: M. immaculata and M. fortis in cluttered moist foothill forest from Costa Rica to upper Amazonia; Gymnocichla nudiceps in moist cluttered second growth of Central America to Colombia. Where the forest understory is more open, Myrmeciza species follow ants mainly in cluttered patches: M. exsul in lowland forest west of the Andes, M. myotherina east of the Andes. Myrmeciza or relatives that specialize on water-edge or very dense zones rarely follow ants.

  3. Edge Effects on Community and Social Structure of Northern Temperate Deciduous Forest Ants

    Directory of Open Access Journals (Sweden)

    Valerie S. Banschbach

    2012-01-01

    Full Text Available Determining how ant communities are impacted by challenges from habitat fragmentation, such as edge effects, will help us understand how ants may be used as a bioindicator taxon. To assess the impacts of edge effects upon the ant community in a northern temperate deciduous forest, we studied edge and interior sites in Jericho, VT, USA. The edges we focused upon were created by recreational trails. We censused the ants at these sites for two consecutive growing seasons using pitfall traps and litter plot excavations. We also collected nests of the most common ant species at our study sites, Aphaenogaster rudis, for study of colony demography. Significantly greater total numbers of ants and ant nests were found in the edge sites compared to the interior sites but rarefaction analysis showed no significant difference in species richness. Aphaenogaster rudis was the numerically dominant ant in the habitats sampled but had a greater relative abundance in the interior sites than in the edge sites both in pitfall and litter plot data. Queen number of A. rudis significantly differed between the nests collected in the edge versus the interior sites. Habitat-dependent changes in social structure of ants represent another possible indicator of ecosystem health.

  4. Reciprocal genomic evolution in the ant-fungus agricultural symbiosis

    DEFF Research Database (Denmark)

    Nygaard, Sanne; Hu, Haofu; Li, Cai

    2016-01-01

    The attine ant-fungus agricultural symbiosis evolved over tens of millions of years, producing complex societies with industrial-scale farming analogous to that of humans. Here we document reciprocal shifts in the genomes and transcriptomes of seven fungus-farming ant species and their fungal...

  5. Patterns of male parentage in the fungus-growing ants

    DEFF Research Database (Denmark)

    Villesen, Palle; Boomsma, JJ

    2003-01-01

    Ant queens from eight species, covering three genera of lower and two genera of higher attine ants, have exclusively or predominantly single mating. The ensuing full-sib colonies thus have a strong potential reproductive conflict between the queen and the workers over male production...

  6. Ant Systems for a Dynamic TSP - Ants Caught in a Traffic Jam

    NARCIS (Netherlands)

    Eyckelhof, C.J.; Dorigo, M.; Caro Di, G.; Snoek, M.; Sampels, M.

    2002-01-01

    In this paper we present a new Ants System approach to a dynamic Travelling Salesman Problem. Here the travel times between the cities are subject to change. To handle this dynamism several ways of adapting the pheromone matrix both locally and globally are considered. We show that the strategy of

  7. Comparative studies of the secretome of fungus-growing ants

    DEFF Research Database (Denmark)

    Linde, Tore; Grell, Morten Nedergaard; Schiøtt, Morten

    2009-01-01

    Leafcutter ants of the species Acromyrmex echinatior live in symbiosis with the fungus Leucoagaricus gongylophorus. The ants harvest fragments of leaves and carry them to the nest where they place the material on the fungal colony. The fungus secretes a wide array of proteins to degrade the leaves...... into nutrients that the ants can feed on. The focus of this study is to discover, characterize and compare the secreted proteins. In order to do so cDNA libraries are constructed from mRNA extracted from the fungus material. The most efficient technology to screen cDNA libraries selectively for secreted...

  8. PARAMETER ESTIMATION OF VALVE STICTION USING ANT COLONY OPTIMIZATION

    Directory of Open Access Journals (Sweden)

    S. Kalaivani

    2012-07-01

    Full Text Available In this paper, a procedure for quantifying valve stiction in control loops based on ant colony optimization has been proposed. Pneumatic control valves are widely used in the process industry. The control valve contains non-linearities such as stiction, backlash, and deadband that in turn cause oscillations in the process output. Stiction is one of the long-standing problems and it is the most severe problem in the control valves. Thus the measurement data from an oscillating control loop can be used as a possible diagnostic signal to provide an estimate of the stiction magnitude. Quantification of control valve stiction is still a challenging issue. Prior to doing stiction detection and quantification, it is necessary to choose a suitable model structure to describe control-valve stiction. To understand the stiction phenomenon, the Stenman model is used. Ant Colony Optimization (ACO, an intelligent swarm algorithm, proves effective in various fields. The ACO algorithm is inspired from the natural trail following behaviour of ants. The parameters of the Stenman model are estimated using ant colony optimization, from the input-output data by minimizing the error between the actual stiction model output and the simulated stiction model output. Using ant colony optimization, Stenman model with known nonlinear structure and unknown parameters can be estimated.

  9. Effects of dam-induced landscape fragmentation on amazonian ant-plant mutualistic networks.

    Science.gov (United States)

    Emer, Carine; Venticinque, Eduardo Martins; Fonseca, Carlos Roberto

    2013-08-01

    Mutualistic networks are critical to biological diversity maintenance; however, their structures and functionality may be threatened by a swiftly changing world. In the Amazon, the increasing number of dams poses a large threat to biological diversity because they greatly alter and fragment the surrounding landscape. Tight coevolutionary interactions typical of tropical forests, such as the ant-myrmecophyte mutualism, where the myrmecophyte plants provide domatia nesting space to their symbiotic ants, may be jeopardized by the landscape changes caused by dams. We analyzed 31 ant-myrmecophyte mutualistic networks in undisturbed and disturbed sites surrounding Balbina, the largest Central Amazonian dam. We tested how ant-myrmecophyte networks differ among dam-induced islands, lake edges, and undisturbed forests in terms of species richness, composition, structure, and robustness (number of species remaining in the network after partner extinctions). We also tested how landscape configuration in terms of area, isolation, shape, and neighborhood alters the structure of the ant-myrmecophyte networks on islands. Ant-myrmecophytic networks were highly compartmentalized in undisturbed forests, and the compartments had few strongly connected mutualistic partners. In contrast, networks at lake edges and on islands were not compartmentalized and were negatively affected by island area and isolation in terms of species richness, density, and composition. Habitat loss and fragmentation led to coextinction cascades that contributed to the elimination of entire ant-plant compartments. Furthermore, many myrmecophytic plants in disturbed sites lost their mutualistic ant partners or were colonized by opportunistic, nonspecialized ants. Robustness of ant-myrmecophyte networks on islands was lower than robustness near lake edges and in undisturbed forest and was particularly susceptible to the extinction of plants. Beyond the immediate habitat loss caused by the building of large dams

  10. Hybridization in East African swarm-raiding army ants

    DEFF Research Database (Denmark)

    Kronauer, Daniel Jc; Peters, Marcell K; Schöning, Caspar

    2011-01-01

    Hybridization can have complex effects on evolutionary dynamics in ants because of the combination of haplodiploid sex-determination and eusociality. While hybrid non-reproductive workers have been found in a range of species, examples of gene-flow via hybrid queens and males are rare. We studied...... hybridization in East African army ants (Dorylus subgenus Anomma) using morphology, mitochondrial DNA sequences, and nuclear microsatellites....

  11. Ants at Ton Nga Chang Wildlife Sanctuary, Songkhla

    Directory of Open Access Journals (Sweden)

    Watanasit, S.

    2005-03-01

    Full Text Available The aim of this study was to investigate diversity of ant at Ton Nga Chang Wildlife Sanctuary, Hat Yai, Songkhla. Three line transects (100 m each were randomly set up in 2 types of forest area, disturbed and undisturbed. Hand collecting (HC and leaf litter sampling (LL were applied for ant collection within a time limit of 30 minutes for each method. This study was carried out every month during Febuary 2002- Febuary 2003. The results showed that 206 species were placed under 8 subfamilies: Aenictinae, Cerapachyinae, Dolichoderinae, Formicinae, Leptanillinae, Myrmicinae, Ponerinae and Pseudomyrmecinae. Study sites and collection methods could divide ant species into 2 groups, whereas seasonal change could not distinguish the groups by DCA of multivariate analysis.

  12. Visual cues for the retrieval of landmark memories by navigating wood ants.

    Science.gov (United States)

    Harris, Robert A; Graham, Paul; Collett, Thomas S

    2007-01-23

    Even on short routes, ants can be guided by multiple visual memories. We investigate here the cues controlling memory retrieval as wood ants approach a one- or two-edged landmark to collect sucrose at a point along its base. In such tasks, ants store the desired retinal position of landmark edges at several points along their route. They guide subsequent trips by retrieving the appropriate memory and moving to bring the edges in the scene toward the stored positions. The apparent width of the landmark turns out to be a powerful cue for retrieving the desired retinal position of a landmark edge. Two other potential cues, the landmark's apparent height and the distance that the ant walks, have little effect on memory retrieval. A simple model encapsulates these conclusions and reproduces the ants' routes in several conditions. According to this model, the ant stores a look-up table. Each entry contains the apparent width of the landmark and the desired retinal position of vertical edges. The currently perceived width provides an index for retrieving the associated stored edge positions. The model accounts for the population behavior of ants and the idiosyncratic training routes of individual ants. Our results imply binding between the edge of a shape and its width and, further, imply that assessing the width of a shape does not depend on the presence of any particular local feature, such as a landmark edge. This property makes the ant's retrieval and guidance system relatively robust to edge occlusions.

  13. Ant-inspired density estimation via random walks.

    Science.gov (United States)

    Musco, Cameron; Su, Hsin-Hao; Lynch, Nancy A

    2017-10-03

    Many ant species use distributed population density estimation in applications ranging from quorum sensing, to task allocation, to appraisal of enemy colony strength. It has been shown that ants estimate local population density by tracking encounter rates: The higher the density, the more often the ants bump into each other. We study distributed density estimation from a theoretical perspective. We prove that a group of anonymous agents randomly walking on a grid are able to estimate their density within a small multiplicative error in few steps by measuring their rates of encounter with other agents. Despite dependencies inherent in the fact that nearby agents may collide repeatedly (and, worse, cannot recognize when this happens), our bound nearly matches what would be required to estimate density by independently sampling grid locations. From a biological perspective, our work helps shed light on how ants and other social insects can obtain relatively accurate density estimates via encounter rates. From a technical perspective, our analysis provides tools for understanding complex dependencies in the collision probabilities of multiple random walks. We bound the strength of these dependencies using local mixing properties of the underlying graph. Our results extend beyond the grid to more general graphs, and we discuss applications to size estimation for social networks, density estimation for robot swarms, and random walk-based sampling for sensor networks.

  14. A global database of ant species abundances

    Science.gov (United States)

    Gibb, Heloise; Dunn, Rob R.; Sanders, Nathan J.; Grossman, Blair F.; Photakis, Manoli; Abril, Silvia; Agosti, Donat; Andersen, Alan N.; Angulo, Elena; Armbrecht, Ingre; Arnan, Xavier; Baccaro, Fabricio B.; Bishop, Tom R.; Boulay, Raphael; Bruhl, Carsten; Castracani, Cristina; Cerda, Xim; Del Toro, Israel; Delsinne, Thibaut; Diaz, Mireia; Donoso, David A.; Ellison, Aaron M.; Enriquez, Martha L.; Fayle, Tom M.; Feener Jr., Donald H.; Fisher, Brian L.; Fisher, Robert N.; Fitpatrick, Matthew C.; Gomez, Cristanto; Gotelli, Nicholas J.; Gove, Aaron; Grasso, Donato A.; Groc, Sarah; Guenard, Benoit; Gunawardene, Nihara; Heterick, Brian; Hoffmann, Benjamin; Janda, Milan; Jenkins, Clinton; Kaspari, Michael; Klimes, Petr; Lach, Lori; Laeger, Thomas; Lattke, John; Leponce, Maurice; Lessard, Jean-Philippe; Longino, John; Lucky, Andrea; Luke, Sarah H.; Majer, Jonathan; McGlynn, Terrence P.; Menke, Sean; Mezger, Dirk; Mori, Alessandra; Moses, Jimmy; Munyai, Thinandavha Caswell; Pacheco, Renata; Paknia, Omid; Pearce-Duvet, Jessica; Pfeiffer, Martin; Philpott, Stacy M.; Resasco, Julian; Retana, Javier; Silva, Rogerio R.; Sorger, Magdalena D.; Souza, Jorge; Suarez, Andrew V.; Tista, Melanie; Vasconcelos, Heraldo L.; Vonshak, Merav; Weiser, Michael D.; Yates, Michelle; Parr, Catherine L.

    2017-01-01

    What forces structure ecological assemblages? A key limitation to general insights about assemblage structure is the availability of data that are collected at a small spatial grain (local assemblages) and a large spatial extent (global coverage). Here, we present published and unpublished data from 51,388 ant abundance and occurrence records of more than 2693 species and 7953 morphospecies from local assemblages collected at 4212 locations around the world. Ants were selected because they are diverse and abundant globally, comprise a large fraction of animal biomass in most terrestrial communities, and are key contributors to a range of ecosystem functions. Data were collected between 1949 and 2014, and include, for each geo-referenced sampling site, both the identity of the ants collected and details of sampling design, habitat type and degree of disturbance. The aim of compiling this dataset was to provide comprehensive species abundance data in order to test relationships between assemblage structure and environmental and biogeographic factors. Data were collected using a variety of standardised methods, such as pitfall and Winkler traps, and will be valuable for studies investigating large-scale forces structuring local assemblages. Understanding such relationships is particularly critical under current rates of global change. We encourage authors holding additional data on systematically collected ant assemblages, especially those in dry and cold, and remote areas, to contact us and contribute their data to this growing dataset.

  15. Effects of invasive European fire ants (Myrmica rubra on herring gull (Larus argentatus reproduction.

    Directory of Open Access Journals (Sweden)

    Luke E DeFisher

    Full Text Available Various invasive ant species have negatively affected reproductive success in birds by disrupting nest site selection, incubation patterns, food supply, and by direct predation on nestlings. Impacts can be particularly severe when non-native ants colonize seabird nesting islands where thousands of birds may nest in high densities on the ground or in burrows or crevices. Here we report on the first documented effects of Myrmica rubra, the European fire ant, on the reproduction of birds in its non-native range. We documented herring gulls (Larus argentatus on Appledore Island, Maine, engaging in more erratic incubation behaviors at nests infested by the ants. Newly-hatched chicks in some nests were swarmed by ants, leading to rapid chick death. Due to high overall rates of chick mortality, survival probabilities did not vary between nests with and without ant activity, however chick growth rates were slower at nests with ants than at ant-free nests. Ant infestation likely leads to longer-term fitness consequences because slower growth rates early in life may ultimately lead to lower post-fledging survival probabilities.

  16. Studies of laboulbeniales (Fungi, Ascomycota) on myrmica ants (II)

    NARCIS (Netherlands)

    Haelewaters, Danny; Boer, Peter; Gort, Gerrit; Noordijk, Jinze

    2015-01-01

    One group of important insect parasites are the Laboulbeniales (Ascomycota), microscopic fungi that live attached to the exterior of their hosts, mainly beetles, but also mites, millipedes, earwigs, and ants. Rickia wasmannii is a common fungus in Europe and is limited to the ant genus Myrmica

  17. Disease dynamics in a specialized parasite of ant societies.

    Directory of Open Access Journals (Sweden)

    Sandra B Andersen

    Full Text Available Coevolution between ant colonies and their rare specialized parasites are intriguing, because lethal infections of workers may correspond to tolerable chronic diseases of colonies, but the parasite adaptations that allow stable coexistence with ants are virtually unknown. We explore the trade-offs experienced by Ophiocordyceps parasites manipulating ants into dying in nearby graveyards. We used field data from Brazil and Thailand to parameterize and fit a model for the growth rate of graveyards. We show that parasite pressure is much lower than the abundance of ant cadavers suggests and that hyperparasites often castrate Ophiocordyceps. However, once fruiting bodies become sexually mature they appear robust. Such parasite life-history traits are consistent with iteroparity--a reproductive strategy rarely considered in fungi. We discuss how tropical habitats with high biodiversity of hyperparasites and high spore mortality has likely been crucial for the evolution and maintenance of iteroparity in parasites with low dispersal potential.

  18. A new fire ant (Hymenoptera: Formicidae) bait base carrier for moist conditions.

    Science.gov (United States)

    Kafle, Lekhnath; Wu, Wen-Jer; Shih, Cheng-Jen

    2010-10-01

    A new water-resistant fire ant bait (T-bait; cypermethrin 0.128%) consisting of dried distillers grains with solubles (DDGS) as a carrier was developed and evaluated against a standard commercial bait (Advion; indoxacarb 0.045%) under both laboratory and field conditions. When applying the normal T-bait or Advion in the laboratory, 100% of Solenopsis invicta Buren worker ants were killed within 4 days. However, when the T-bait and Advion were wetted, 70.6 and 39.7% of the ants were killed respectively. Under field conditions, dry T-bait and dry Advion had almost the same efficacy against ant colonies. However, when T-bait and Advion came in contact with water, the former's ability to kill S. invicta colonies in the field was only marginally reduced, while Advion lost virtually all of its activity. In addition, DDGS was also shown to be compatible with a number of other insecticides, such as d-allethrin, permethrin and pyrethrin. Based on its properties of remaining attractive to the fire ants when wetted, combined with its ant-killing abilities both in the laboratory and in the field, T-bait is an efficient fire ant bait, especially under moist conditions.

  19. Los derechos de las víctimas de la violencia política a la verdad, la reparación y la justicia. Reflexiones sobre cuatro casos en América Latina

    Directory of Open Access Journals (Sweden)

    Francisco Cortés Rodas

    2007-01-01

    Full Text Available A partir de los antecedentes teóricos de la justicia transicional y el examen de algunos casos en los que ésta se aplicó en América Latina, el autor pone en tensión la necesidad de paz y por ende de olvido de los gobiernos en medio de conflictos armados y las exigencias de justicia y resarcimiento de las víctimas; esto con el fin de justificar su posición con relación al objetivo que debe buscar la justicia transicional, a saber, que éste debe estar restringido exclusivamente a la rehabilitación de las víctimas políticas y no tiene que ver ni con la reestructuración total de la sociedad ni con el trato de las grandes injusticias sociales del pasado.

  20. Escuela, conocimiento y saber NASA. Aspectos críticos para una política educativa intercultural en Colombia

    Directory of Open Access Journals (Sweden)

    Víctor Alonso Molina Bedoya

    2015-09-01

    Full Text Available El artículo presenta los resultados alusivos a la educación, el saber y el conocer de la investigación: “Cosmovisión de la unidad en un territorio indígena de Colombia”. El proyecto tuvo como propósito reconocer las relaciones entre el ocio, la producción, la educación y el desarrollo sostenible y se realizó a partir de un ejercicio etnográfico, a la manera de un oficiar el sentido y la mirada para explorar las tramas de sentido cultural de la comunidad. Lo que implicó una estadía en el resguardo indígena por más de 180 días, durante los cuales se realizó observación de diversas prácticas cotidianas y entrevistas semi-estructuradas que fueron registradas en el diario de campo. El análisis se hizo a partir del método de comparación constante. Como resultados se destacan: la tensión entre las prácticas educativas propias y el interés integracionista de la educación oficial. Al igual que el deseo de las comunidades por consolidar sus procesos formativos desde una relación respetuosa de los saberes, los seres y de lo social. A manera de conclusión se manifiesta quees necesario avanzar en la construcción de proyectos educativos simétricos que permitan el diálogo de seres y de saberes para edificar la nación diversa, como está plasmado en la Constitución Política de 1991 donde se reconoce a Colombia como una nación multicultural y pluriétnica.

  1. Coevolved crypts and exocrine glands support mutualistic bacteria in fungus-growing ants

    DEFF Research Database (Denmark)

    Currie, Cameron R; Poulsen, Michael; Mendenhall, John

    2006-01-01

    Attine ants engage in a quadripartite symbiosis with fungi they cultivate for food, specialized garden parasites, and parasite-inhibiting bacteria. Molecular phylogenetic evidence supports an ancient host-pathogen association between the ant-cultivar mutualism and the garden parasite. Here we show...... that ants rear the antibiotic-producing bacteria in elaborate cuticular crypts, supported by unique exocrine glands, and that these structures have been highly modified across the ants' evolutionary history. This specialized structural evolution, together with the absence of these bacteria and modifications...

  2. Saber y conocer: Un plan para su ensenaza (To know and to be acquainted with: A teaching plan).

    Science.gov (United States)

    Lizardi-Rivera, Carmen M.

    1995-01-01

    Focuses on how to teach English-speaking students of Spanish the practical distinction between the verbs, "saber" (to be cognizant of) and "conocer" (to be acquainted with). This article describes a solution proposed by K. Taylor for explaining the limits of the two verbs and examines similar proposals delineated in three other Spanish textbooks.…

  3. Absence of jamming in ant trails: feedback control of self-propulsion and noise.

    Science.gov (United States)

    Chaudhuri, Debasish; Nagar, Apoorva

    2015-01-01

    We present a model of ant traffic considering individual ants as self-propelled particles undergoing single-file motion on a one-dimensional trail. Recent experiments on unidirectional ant traffic in well-formed natural trails showed that the collective velocity of ants remains approximately unchanged, leading to the absence of jamming even at very high densities [John et al., Phys. Rev. Lett. 102, 108001 (2009)]. Assuming a feedback control mechanism of self-propulsion force generated by each ant using information about the distance from the ant in front, our model captures all the main features observed in the experiment. The distance headway distribution shows a maximum corresponding to separations within clusters. The position of this maximum remains independent of average number density. We find a non-equilibrium first-order transition, with the formation of an infinite cluster at a threshold density where all the ants in the system suddenly become part of a single cluster.

  4. Macrodinychus mites as parasitoids of invasive ants: an overlooked parasitic association.

    Science.gov (United States)

    Lachaud, Jean-Paul; Klompen, Hans; Pérez-Lachaud, Gabriela

    2016-07-21

    Mites are frequent ant symbionts, yet the exact nature of their interactions with their hosts is poorly known. Generally, myrmecophilous mites show adaptations for dispersal through phoresis, but species that lack such an adaptation may have evolved unusual specialized relationships with their hosts. The immature stages of Macrodinychus multispinosus develop as ectoparasitoids of pupae of the invasive ant Paratrechina longicornis. Feeding stages show regressed locomotor appendages. These mites complete their development on a single host, sucking all of its body content and therefore killing it. Locally high proportions of parasitized host pupae suggest that M. multispinosus could serve as a biological control agent. This is the ninth species of Macrodinychus reported as ant parasite, and the third known as parasitoid of invasive ants, confirming a unique habit in the evolution of mite feeding strategies and suggesting that the entire genus might be parasitic on ants. Several mites' characteristics, such as their protective morphology, possible viviparity, lack of a specialized stage for phoretic dispersal, and low host specificity, combined with both the general low aggressiveness of invasive P. longicornis towards other ants and its possible susceptibility to generalist ectoparasites would account for the host shift in native macrodinychid mites.

  5. Tree-Dwelling Ants: Contrasting Two Brazilian Cerrado Plant Species without Extrafloral Nectaries

    Directory of Open Access Journals (Sweden)

    Jonas Maravalhas

    2012-01-01

    Full Text Available Ants dominate vegetation stratum, exploiting resources like extrafloral nectaries (EFNs and insect honeydew. These interactions are frequent in Brazilian cerrado and are well known, but few studies compare ant fauna and explored resources between plant species. We surveyed two cerrado plants without EFNs, Roupala montana (found on preserved environments of our study area and Solanum lycocarpum (disturbed ones. Ants were collected and identified, and resources on each plant noted. Ant frequency and richness were higher on R. montana (67%; 35 spp than S. lycocarpum (52%; 26, the occurrence of the common ant species varied between them, and similarity was low. Resources were explored mainly by Camponotus crassus and consisted of scale insects, aphids, and floral nectaries on R. montana and two treehopper species on S. lycocarpum. Ants have a high diversity on cerrado plants, exploring liquid and prey-based resources that vary in time and space and affect their presence on plants.

  6. Ants use partner specific odors to learn to recognize a mutualistic partner.

    Directory of Open Access Journals (Sweden)

    Masaru K Hojo

    Full Text Available Regulation via interspecific communication is an important for the maintenance of many mutualisms. However, mechanisms underlying the evolution of partner communication are poorly understood for many mutualisms. Here we show, in an ant-lycaenid butterfly mutualism, that attendant ants selectively learn to recognize and interact cooperatively with a partner. Workers of the ant Pristomyrmex punctatus learn to associate cuticular hydrocarbons of mutualistic Narathura japonica caterpillars with food rewards and, as a result, are more likely to tend the caterpillars. However, the workers do not learn to associate the cuticular hydrocarbons of caterpillars of a non-ant-associated lycaenid, Lycaena phlaeas, with artificial food rewards. Chemical analysis revealed cuticular hydrocarbon profiles of the mutualistic caterpillars were complex compared with those of non-ant-associated caterpillars. Our results suggest that partner-recognition based on partner-specific chemical signals and cognitive abilities of workers are important mechanisms underlying the evolution and maintenance of mutualism with ants.

  7. A diverse ant fauna from the mid-cretaceous of Myanmar (Hymenoptera: Formicidae.

    Directory of Open Access Journals (Sweden)

    Phillip Barden

    Full Text Available A new collection of 24 wingless ant specimens from mid-Cretaceous Burmese amber (Albian-Cenomanian, 99 Ma comprises nine new species belonging to the genus Sphecomyrmodes Engel and Grimaldi. Described taxa vary considerably with regard to total size, head and body proportion, cuticular sculpturing, and petiole structure while all species are unified by a distinct shared character. The assemblage represents the largest known diversification of closely related Cretaceous ants with respect to species number. These stem-group ants exhibit some characteristics previously known only from their extant counterparts along with presumed plesiomorphic morphology. Consequently, their morphology may inform hypotheses relating to basal relationships and general patterns of ant evolution. These and other uncovered Cretaceous species indicate that stem-group ants are not simply wasp-like, transitional formicids, but rather a group of considerable adaptive diversity, exhibiting innovations analogous to what crown-group ants would echo 100 million years later.

  8. A preliminary checklist of the ants (Hymenoptera: Formicidae) of ...

    African Journals Online (AJOL)

    A preliminary species checklist of the ants (Hymenoptera: Formicidae) of. Kakamega Forest, Western Kenya, is presented. The species list is based on specimens sampled from 1999 until 2009, which are deposited in the ant collection of the Zoological Research Museum Koenig, Bonn, Germany, and the Natural History ...

  9. Construindo o diálogo entre saberes para ressignificar a ação educativa em saúde Construyendo el diálogo entre saberes para resignificar la acción educativa en salud Establishing a dialogue regarding technical-scientific and common sense knowledge for an effective health education

    Directory of Open Access Journals (Sweden)

    Valéria Marli Leonello

    2009-01-01

    Full Text Available OBJETIVO: Identificar, na perspectiva dos diferentes sujeitos implicados, as possibilidades de aproximação entre o saber profissional e o de senso comum, envolvidos nas atividades educativas desenvolvidas pela enfermeira em seu processo de trabalho assistencial. MÉTODOS: Utilizou-se como referencial teórico-metodológico o materialismo histórico e dialético. Foram entrevistados 30 sujeitos: cinco docentes, cinco graduandos, dez enfermeiras; dois gestores e oito usuários de dois serviços de saúde. Os discursos foram submetidos à análise de discurso. RESULTADOS: Os discursos revelaram que os profissionais valorizam a alteridade, ou seja, a presença e a voz do usuário dos serviços de saúde. Os usuários sinalizaram sua autonomia como "sujeitos em relação" com o saber técnico-científico. CONCLUSÃO: A articulação dos diferentes saberes é fundamental para o desenvolvimento de ações educativas mais dialógicas, participativas e potencialmente transformadoras da realidade em saúde.OBJETIVO: Identificar, en la perspectiva de los diferentes sujetos implicados, las posibilidades de aproximación entre el saber profesional y el de sentido común, involucrados en las actividades educativas desarrolladas por la enfermera en su proceso de trabajo asistencial. MÉTODOS: Se utilizó como referencial teórico-metodológico el materialismo histórico y dialético. Fueron entrevistados 30 sujetos: cinco docentes, cinco graduados, diez enfermeras; dos gestores y ocho usuarios de dos servicios de salud. Los discursos fueron sometidos al análisis de discurso. RESULTADOS: Los discursos revelaron que los profesionales valorizan la alteridad, o sea, la presencia y la voz del usuario de los servicios de salud. Los usuarios señalaron su autonomía como "sujetos en relación" con el saber técnico-científico. CONCLUSIÓN: La articulación de los diferentes saberes es fundamental para el desarrollo de acciones educativas más dial

  10. Automatic optimization of a nuclear reactor reload using the algorithm Ant-Q; A otimizacao automatica da recarga nuclear utilizando o algoritmo Ant-Q

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Liana; Schirru, Roberto [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear

    2002-07-01

    The nuclear fuel reload optimization is a NP-Complete combinatorial optimization problem. For decades this problem was solved using an expert's knowledge. From the eighties, however there have been efforts to automatic fuel reload and the more recent ones show the Genetic Algorithm's (GA) efficiency on this problem. Following this trend, our aim is to optimization nuclear fuel reload using Ant-Q, artificial theory based algorithms. Ant-Q's results on the Traveling salesman Problem, which is conceptuality similar to fuel reload, are better than GA's. Ant-Q was tested in real application on the cycle 7 reload of Angra I. Comparing Ant-Q result with the GA's, it can be verified that, even without a local heuristics, the former algorithm, as it superiority comparing the GA in Angra I show. Is a valid technique to solve the nuclear fuel reload problem. (author)

  11. Characterization of actinobacteria associated with three ant-plant mutualisms.

    Science.gov (United States)

    Hanshew, Alissa S; McDonald, Bradon R; Díaz Díaz, Carol; Djiéto-Lordon, Champlain; Blatrix, Rumsaïs; Currie, Cameron R

    2015-01-01

    Ant-plant mutualisms are conspicuous and ecologically important components of tropical ecosystems that remain largely unexplored in terms of insect-associated microbial communities. Recent work has revealed that ants in some ant-plant systems cultivate fungi (Chaetothyriales) within their domatia, which are fed to larvae. Using Pseudomyrmex penetrator/Tachigali sp. from French Guiana and Petalomyrmex phylax/Leonardoxa africana and Crematogaster margaritae/Keetia hispida, both from Cameroon, as models, we tested the hypothesis that ant-plant-fungus mutualisms co-occur with culturable Actinobacteria. Using selective media, we isolated 861 putative Actinobacteria from the three systems. All C. margaritae/K. hispida samples had culturable Actinobacteria with a mean of 10.0 colony forming units (CFUs) per sample, while 26 % of P. penetrator/Tachigali samples (mean CFUs 1.3) and 67 % of P. phylax/L. africana samples (mean CFUs 3.6) yielded Actinobacteria. The largest number of CFUs was obtained from P. penetrator workers, P. phylax alates, and C. margaritae pupae. 16S rRNA gene sequencing and phylogenetic analysis revealed the presence of four main clades of Streptomyces and one clade of Nocardioides within these three ant-plant mutualisms. Streptomyces with antifungal properties were isolated from all three systems, suggesting that they could serve as protective symbionts, as found in other insects. In addition, a number of isolates from a clade of Streptomyces associated with P. phylax/L. africana and C. margaritae/K. hispida were capable of degrading cellulose, suggesting that Streptomyces in these systems may serve a nutritional role. Repeated isolation of particular clades of Actinobacteria from two geographically distant locations supports these isolates as residents in ant-plant-fungi niches.

  12. Hybrid Bee Ant Colony Algorithm for Effective Load Balancing And ...

    African Journals Online (AJOL)

    PROF. OLIVER OSUAGWA

    Ant Colony algorithm is used in this hybrid Bee Ant Colony algorithm to solve load balancing issues ... Genetic Algorithm (MO-GA) for dynamic job scheduling that .... Information Networking and Applications Workshops. [7]. M. Dorigo & T.

  13. The interplay between scent trails and group-mass recruitment systems in ants

    NARCIS (Netherlands)

    Planque, R.; van den Berg, G.J.B.; Franks, N.R.

    2013-01-01

    Large ant colonies invariably use effective scent trails to guide copious ant numbers to food sources. The success of mass recruitment hinges on the involvement of many colony members to lay powerful trails. However, many ant colonies start off as single queens. How do these same colonies forage

  14. Evolution of Fungal enzymes in the attine ant symbiosis

    DEFF Research Database (Denmark)

    de Fine Licht, Henrik Hjarvard; Schiøtt, Morten; Boomsma, Jacobus Jan

    The attine ant symbiosis is characterized by ancient but varying degrees of diffuse co-evolution between the ants and their fungal cultivars. Domesticated fungi became dependent on vertical transmission by queens and the ant colonies came to rely on their symbiotic fungus for food and thus...... as garden substrate, whereas the more basal genera use leaf litter, insect feces and insect carcasses. We hypothesized that enzyme activity of fungal symbionts has co-evolved with substrate use and we measured enzyme activities of fungus gardens in the field to test this, focusing particularly on plant...... essential for the symbiosis in general, but have contributed specifically to the evolution of the symbiosis....

  15. Social context predicts recognition systems in ant queens

    DEFF Research Database (Denmark)

    Dreier, Stéphanie Agnès Jeanine; d'Ettorre, Patrizia

    2009-01-01

    Recognition of group-members is a key feature of sociality. Ants use chemical communication to discriminate nestmates from intruders, enhancing kin cooperation and preventing parasitism. The recognition code is embedded in their cuticular chemical profile, which typically varies between colonies....... We predicted that ants might be capable of accurate recognition in unusual situations when few individuals interact repeatedly, as new colonies started by two to three queens. Individual recognition would be favoured by selection when queens establish dominance hierarchies, because repeated fights...... for dominance are costly; but it would not evolve in absence of hierarchies. We previously showed that Pachycondyla co-founding queens, which form dominance hierarchies, have accurate individual recognition based on chemical cues. Here, we used the ant Lasius niger to test the null hypothesis that individual...

  16. Ant colonies prefer infected over uninfected nest sites

    DEFF Research Database (Denmark)

    Pontieri, Luigi; Vojvodic, Svjetlana; Graham, Riley

    2014-01-01

    with sporulating mycelium of the entomopathogenic fungus Metarhizium brunneum (infected nests), nests containing nestmates killed by freezing (uninfected nests), and empty nests. In contrast to the expectation pharaoh ant colonies preferentially (84%) moved into the infected nest when presented with the choice...... the high risk of epidemics in group-living animals. Choosing nest sites free of pathogens is hypothesized to be highly efficient in invasive ants as each of their introduced populations is often an open network of nests exchanging individuals (unicolonial) with frequent relocation into new nest sites...... and low genetic diversity, likely making these species particularly vulnerable to parasites and diseases. We investigated the nest site preference of the invasive pharaoh ant, Monomorium pharaonis, through binary choice tests between three nest types: nests containing dead nestmates overgrown...

  17. Saberes relacionados ao autocuidado entre mulheres da área rural do sul do brasil

    OpenAIRE

    Thum, Moara Ailane; Ceolin, Teila; Universidade Federal de Pelotas; Borges, Anelise Miritz; Heck, Rita Maria; Universidade Federal de Pelotas

    2011-01-01

    Este estudo teve por objetivo conhecer as ações de autocuidado de um grupo de mulheres rurais do município de Pelotas, Rio Grande do Sul. Tratou-se de uma pesquisa qualitativa, com 11 mulheres, residentes na área rural do município. A coleta de dados ocorreu entre maio e junho de 2010, através de entrevista semiestruturada. Foi realizada a análise de conteúdo por temas. As informantes mais antigas participam do grupo na comunidade há 12 anos, realizando trabalhos manuais e trocas de saberes s...

  18. A estética como factor promotor da aprendizagem

    Directory of Open Access Journals (Sweden)

    Fátima Maria BEZERRA BARBOSA

    2012-02-01

    Full Text Available La reflexión filosófica sobre el arte, lo hermoso, lo bueno, lo verdadero y su capacidad de promover el desarrollo humano es un tema que remonta a Platón en la cultura occidental. Considerando que la educación debe ser entendida como un fenómeno integral, que abarca no sólo las dimensiones intelectuales sino también las dimensiones sensibles, la intuición y el raciocinio, las capacidades imaginativas y creativas, el «saber ser» y el «saber estar» parejas del «conocer» y del «saber hacer», pensamos que es incuestionable la importancia de la estética en el fenómeno educativo. El objetivo de este trabajo es demostrar la importancia de la educación estética como motor fundamental de desarrollo humano y, en este sentido, como catalizador de la motivación y del aprendizaje, para que, a través de la imaginación y de la creatividad, sea posible la innovación en la construcción de vías alternativas para un mundo más humano y placentero.

  19. Co-evolution of enzyme function in the attine ant-fungus symbiosis

    DEFF Research Database (Denmark)

    de Fine Licht, Henrik Hjarvard; Schiøtt, Morten; Boomsma, Jacobus Jan

    Introduction: Fungus-growing ants cultivate specialized fungi in the tribe Leucocoprineae (Lepiotaceae: Basidiomycota) inside their nests. The conspicuous leaf-cutting ants in the genus Atta build huge nests displacing several cubic meters of soil, whereas lower attine genera such as Cyphomyrmex ...... garden. This system can be viewed as ant induced crop optimization similar to human agricultural practices....... have small nests with a fungus garden the size of a table-tennis ball. Only the leaf-cutting ants are specialized on using fresh leaves as substrate for their fungus gardens, whereas the more basal attine genera use substrates such as dry plant material (leaf litter and small twigs) and also insect...... feces and insect carcasses. This diverse array of fungal substrates across the attine lineage implies that the symbiotic fungus needs different enzymes to break down the plant material that the ants provide or different efficiencies of enzyme function. Methods: (1.) We made a literature survey...

  20. Leaf endophyte load influences fungal garden development in leaf-cutting ants

    Directory of Open Access Journals (Sweden)

    Van Bael Sunshine A

    2012-11-01

    Full Text Available Abstract Background Previous work has shown that leaf-cutting ants prefer to cut leaf material with relatively low fungal endophyte content. This preference suggests that fungal endophytes exact a cost on the ants or on the development of their colonies. We hypothesized that endophytes may play a role in their host plants’ defense against leaf-cutting ants. To measure the long-term cost to the ant colony of fungal endophytes in their forage material, we conducted a 20-week laboratory experiment to measure fungal garden development for colonies that foraged on leaves with low or high endophyte content. Results Colony mass and the fungal garden dry mass did not differ significantly between the low and high endophyte feeding treatments. There was, however, a marginally significant trend toward greater mass of fungal garden per ant worker in the low relative to the high endophyte treatment. This trend was driven by differences in the fungal garden mass per worker from the earliest samples, when leaf-cutting ants had been foraging on low or high endophyte leaf material for only 2 weeks. At two weeks of foraging, the mean fungal garden mass per worker was 77% greater for colonies foraging on leaves with low relative to high endophyte loads. Conclusions Our data suggest that the cost of endophyte presence in ant forage material may be greatest to fungal colony development in its earliest stages, when there are few workers available to forage and to clean leaf material. This coincides with a period of high mortality for incipient colonies in the field. We discuss how the endophyte-leaf-cutter ant interaction may parallel constitutive defenses in plants, whereby endophytes reduce the rate of colony development when its risk of mortality is greatest.

  1. Disentangling the diversity of arboreal ant communities in tropical forest trees.

    Science.gov (United States)

    Klimes, Petr; Fibich, Pavel; Idigel, Cliffson; Rimandai, Maling

    2015-01-01

    Tropical canopies are known for their high abundance and diversity of ants. However, the factors which enable coexistence of so many species in trees, and in particular, the role of foragers in determining local diversity, are not well understood. We censused nesting and foraging arboreal ant communities in two 0.32 ha plots of primary and secondary lowland rainforest in New Guinea and explored their species diversity and composition. Null models were used to test if the records of species foraging (but not nesting) in a tree were dependent on the spatial distribution of nests in surrounding trees. In total, 102 ant species from 389 trees occurred in the primary plot compared with only 50 species from 295 trees in the secondary forest plot. However, there was only a small difference in mean ant richness per tree between primary and secondary forest (3.8 and 3.3 sp. respectively) and considerably lower richness per tree was found only when nests were considered (1.5 sp. in both forests). About half of foraging individuals collected in a tree belonged to species which were not nesting in that tree. Null models showed that the ants foraging but not nesting in a tree are more likely to nest in nearby trees than would be expected at random. The effects of both forest stage and tree size traits were similar regardless of whether only foragers, only nests, or both datasets combined were considered. However, relative abundance distributions of species differed between foraging and nesting communities. The primary forest plot was dominated by native ant species, whereas invasive species were common in secondary forest. This study demonstrates the high contribution of foragers to arboreal ant diversity, indicating an important role of connectivity between trees, and also highlights the importance of primary vegetation for the conservation of native ant communities.

  2. A phylogenetic perspective on the association between ants (Hymenoptera: Formicidae) and black yeasts (Ascomycota: Chaetothyriales).

    Science.gov (United States)

    Vasse, Marie; Voglmayr, Hermann; Mayer, Veronika; Gueidan, Cécile; Nepel, Maximilian; Moreno, Leandro; de Hoog, Sybren; Selosse, Marc-André; McKey, Doyle; Blatrix, Rumsaïs

    2017-03-15

    The frequency and the geographical extent of symbiotic associations between ants and fungi of the order Chaetothyriales have been highlighted only recently. Using a phylogenetic approach based on seven molecular markers, we showed that ant-associated Chaetothyriales are scattered through the phylogeny of this order. There was no clustering according to geographical origin or to the taxonomy of the ant host. However, strains tended to be clustered according to the type of association with ants: strains from ant-made carton and strains from plant cavities occupied by ants ('domatia') rarely clustered together. Defining molecular operational taxonomic units (MOTUs) with an internal transcribed spacer sequence similarity cut-off of 99% revealed that a single MOTU could be composed of strains collected from various ant species and from several continents. Some ant-associated MOTUs also contained strains isolated from habitats other than ant-associated structures. Altogether, our results suggest that the degree of specialization of the interactions between ants and their fungal partners is highly variable. A better knowledge of the ecology of these interactions and a more comprehensive sampling of the fungal order are needed to elucidate the evolutionary history of mutualistic symbioses between ants and Chaetothyriales. © 2017 The Author(s).

  3. Plant-ants feed their host plant, but above all a fungal symbiont to recycle nitrogen.

    Science.gov (United States)

    Defossez, Emmanuel; Djiéto-Lordon, Champlain; McKey, Doyle; Selosse, Marc-André; Blatrix, Rumsaïs

    2011-05-07

    In ant-plant symbioses, plants provide symbiotic ants with food and specialized nesting cavities (called domatia). In many ant-plant symbioses, a fungal patch grows within each domatium. The symbiotic nature of the fungal association has been shown in the ant-plant Leonardoxa africana and its protective mutualist ant Petalomyrmex phylax. To decipher trophic fluxes among the three partners, food enriched in (13)C and (15)N was given to the ants and tracked in the different parts of the symbiosis up to 660 days later. The plant received a small, but significant, amount of nitrogen from the ants. However, the ants fed more intensively the fungus. The pattern of isotope enrichment in the system indicated an ant behaviour that functions specifically to feed the fungus. After 660 days, the introduced nitrogen was still present in the system and homogeneously distributed among ant, plant and fungal compartments, indicating efficient recycling within the symbiosis. Another experiment showed that the plant surface absorbed nutrients (in the form of simple molecules) whether or not it is coated by fungus. Our study provides arguments for a mutualistic status of the fungal associate and a framework for investigating the previously unsuspected complexity of food webs in ant-plant mutualisms.

  4. Dispersal for survival: some observations on the trunk ant (Formica truncorum Fabricius)

    NARCIS (Netherlands)

    Mabelis, A.A.; Korczynska, J.

    2001-01-01

    The survival chance of the trunk ant (Formica truncorum) is compared with the survival chance of two other species of red wood ants: F.rufa and F.polyctena. Nest populations of F.truncorum are much smaller than nest populations of the other red wood ant species, which makes the species a weaker

  5. Behavioral mechanisms and morphological symptoms of zombie ants dying from fungal infection

    Directory of Open Access Journals (Sweden)

    Himaman Winanda

    2011-05-01

    Full Text Available Abstract Background Parasites that manipulate host behavior can provide prominent examples of extended phenotypes: parasite genomes controlling host behavior. Here we focus on one of the most dramatic examples of behavioral manipulation, the death grip of ants infected by Ophiocordyceps fungi. We studied the interaction between O. unilateralis s.l. and its host ant Camponotus leonardi in a Thai rainforest, where infected ants descend from their canopy nests down to understory vegetation to bite into abaxial leaf veins before dying. Host mortality is concentrated in patches (graveyards where ants die on sapling leaves ca. 25 cm above the soil surface where conditions for parasite development are optimal. Here we address whether the sequence of ant behaviors leading to the final death grip can also be interpreted as parasite adaptations and describe some of the morphological changes inside the heads of infected workers that mediate the expression of the death grip phenotype. Results We found that infected ants behave as zombies and display predictable stereotypical behaviors of random rather than directional walking, and of repeated convulsions that make them fall down and thus precludes returning to the canopy. Transitions from erratic wandering to death grips on a leaf vein were abrupt and synchronized around solar noon. We show that the mandibles of ants penetrate deeply into vein tissue and that this is accompanied by extensive atrophy of the mandibular muscles. This lock-jaw means the ant will remain attached to the leaf after death. We further present histological data to show that a high density of single celled stages of the parasite within the head capsule of dying ants are likely to be responsible for this muscular atrophy. Conclusions Extended phenotypes in ants induced by fungal infections are a complex example of behavioral manipulation requiring coordinated changes of host behavior and morphology. Future work should address the

  6. Evolutionary transition from single to multiple mating in fungus-growing ants

    DEFF Research Database (Denmark)

    Villesen, Palle; Gertsch, P J; Frydenberg, Jane

    1999-01-01

    Queens of leafcutter ants exhibit the highest known levels of multiple mating (up to 10 mates per queen) among ants. Multiple mating may have been selected to increase genetic diversity among nestmate workers, which is hypothesized to be critical in social systems with large, long-lived colonies...... under severe pressure of pathogens. Advanced fungus-growing (leafcutter) ants have large numbers (104-106 workers) and long-lived colonies, whereas basal genera in the attine tribe have small (... to have lower queen mating frequencies, similar to those found in most other ants. We tested this prediction by analysing queen mating frequency and colony kin structure in three basal attine species: Myrmicocrypta ednaella, Apterostigma collare and Cyphomyrmex longiscapus. Microsatellite marker analyses...

  7. Modeling no-jam traffic in ant trails: a pheromone-controlled approach

    Science.gov (United States)

    Guo, Ning; Hu, Mao-Bin; Jiang, Rui; Ding, Jianxun; Ling, Xiang

    2018-05-01

    The experiment in John et al (2009 Phys. Rev. Lett. 102 108001) shows that when ants move in a single-file trail, no jam emerges even at very high densities. We propose a self-propelled model of ant traffic to reproduce the fundamental diagram without a jammed branch. In this model, ants can adjust their desired velocities actively by perceiving pheromone concentration near the front of the trail. Moreover, ants will bear the repulsive force when they have physical contact with neighbors. The velocity in the simulation decreases slightly with increasing density, which captures the main feature observed in the experiment. Distributions of velocity and distance headway basically also conform to the experimental ones.

  8. Isolation of a pyrazine alarm pheromone component from the fire ant, Solenopsis invicta.

    Science.gov (United States)

    Vander Meer, Robert K; Preston, Catherine A; Choi, Man-Yeon

    2010-02-01

    Alarm pheromones in social insects are an essential part of a complex of pheromone interactions that contribute to the maintenance of colony integrity and sociality. The alarm pheromones of ants were among the first examples of animal pheromones identified, primarily because of the large amount of chemical produced and the distinctive responses of ants to the pheromone. However, the alarm pheromone of the fire ant, Solenopsis invicta, eluded identification for over four decades. We identified 2-ethyl-3,6-dimethylpyrazine as an alarm pheromone component of S. invicta. Worker fire ants detect the pyrazine alarm pheromone at 30 pg/ml, which is comparable to alarm pheromone sensitivities reported for other ant species. The source of this alarm pheromone are the mandibular glands, which, in fire ants, are not well developed and contain only about 300 pg of the compound, much less than the microgram quantities of alarm pheromones reported for several other ant species. Female and male sexuals and workers produce the pyrazine, which suggests that it may be involved in fire ant mating flight initiation, as well as the typical worker alarm response. This is the first report of 2-ethyl-3,6-dimethylpyrazine from a Solenopsis species and the first example of this alkaloid functioning as an alarm pheromone.

  9. Canopy cover negatively affects arboreal ant species richness in a tropical open habitat

    Directory of Open Access Journals (Sweden)

    A. C. M. Queiroz

    Full Text Available Abstract We tested the hypothesis of a negative relationship between vegetation characteristics and ant species richness in a Brazilian open vegetation habitat, called candeial. We set up arboreal pitfalls to sample arboreal ants and measured the following environmental variables, which were used as surrogate of environmental heterogeneity: tree richness, tree density, tree height, circumference at the base of the plants, and canopy cover. Only canopy cover had a negative effect on the arboreal ant species richness. Vegetation characteristics and plant species composition are probably homogeneous in candeial, which explains the lack of relationship between other environmental variables and ant richness. Open vegetation habitats harbor a large number of opportunistic and generalist species, besides specialist ants from habitats with high temperatures. An increase in canopy cover decreases sunlight incidence and may cause local microclimatic differences, which negatively affect the species richness of specialist ants from open areas. Canopy cover regulates the richness of arboreal ants in open areas, since only few ant species are able to colonize sites with dense vegetation; most species are present in sites with high temperature and luminosity. Within open vegetation habitats the relationship between vegetation characteristics and species richness seems to be the opposite from closed vegetation areas, like forests.

  10. Salticid predation as one potential driving force of ant mimicry in jumping spiders

    Science.gov (United States)

    Huang, Jin-Nan; Cheng, Ren-Chung; Li, Daiqin; Tso, I-Min

    2011-01-01

    Many spiders possess myrmecomorphy, and species of the jumping spider genus Myrmarachne exhibit nearly perfect ant mimicry. Most salticids are diurnal predators with unusually high visual acuity that prey on various arthropods, including conspecifics. In this study, we tested whether predation pressure from large jumping spiders is one possible driving force of perfect ant mimicry in jumping spiders. The results showed that small non-ant-mimicking jumping spiders were readily treated as prey by large ones (no matter whether heterospecific or conspecific) and suffered high attack and mortality rates. The size difference between small and large jumping spiders significantly affected the outcomes of predatory interactions between them: the smaller the juvenile jumping spiders, the higher the predation risk from large ones. The attack and mortality rates of ant-mimicking jumping spiders were significantly lower than those of non-ant-mimicking jumping spiders, indicating that a resemblance to ants could provide protection against salticid predation. However, results of multivariate behavioural analyses showed that the responses of large jumping spiders to ants and ant-mimicking salticids differed significantly. Results of this study indicate that predation pressure from large jumping spiders might be one selection force driving the evolution of nearly perfect myrmecomorphy in spiders and other arthropods. PMID:20961898

  11. An ant-plant mutualism through the lens of cGMP-dependent kinase genes.

    Science.gov (United States)

    Malé, Pierre-Jean G; Turner, Kyle M; Doha, Manjima; Anreiter, Ina; Allen, Aaron M; Sokolowski, Marla B; Frederickson, Megan E

    2017-09-13

    In plant-animal mutualisms, how an animal forages often determines how much benefit its plant partner receives. In many animals, foraging behaviour changes in response to foraging gene expression or activation of the cGMP-dependent protein kinase (PKG) that foraging encodes. Here, we show that this highly conserved molecular mechanism affects the outcome of a plant-animal mutualism. We studied the two PKG genes of Allomerus octoarticulatus, an Amazonian ant that defends the ant-plant Cordia nodosa against herbivores. Some ant colonies are better 'bodyguards' than others. Working in the field in Peru, we found that colonies fed with a PKG activator recruited more workers to attack herbivores than control colonies. This resulted in less herbivore damage. PKG gene expression in ant workers correlated with whether an ant colony discovered an herbivore and how much damage herbivores inflicted on leaves in a complex way; natural variation in expression levels of the two genes had significant interaction effects on ant behaviour and herbivory. Our results suggest a molecular basis for ant protection of plants in this mutualism. © 2017 The Author(s).

  12. LA INVENCIÓN DE UN SABER METODOLÓGICO

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    Agustín Hernando

    2005-12-01

    Full Text Available RESUMEN:La identidad de la didáctica de la geografía, el conjunto de inquietudes y saberes que actualmente sostenemos acerca de la enseñanza y aprendizaje de la geografia, es un discurso creado, esencialmente,en el transcurso del siglo XX. Las primeras aportaciones corresponden a sus umbrales y primeras décadas siguientes. Acusan dos anhelos: el deseo de ampliar su estudio, extendiéndolo a todos los niveles o grados educativos; y su mejora denunciando unas prácticas degradantes y animando a introducir otras. El carisma de sus protagonistas, el uso de argumentos muy emotivos y la reiterada apelación a los logros conseguidos en otros países son algunas de las señas de identidad de esta primera etapa. El discurso se irá enriqueciendo y diversificando lentamente, durante las siguientes décadas, tal como acredita la literatura disponible. El configurado en las dos últimas décadas del siglo exhibe otras preocupaciones, expectativas, vocabulario y argumentos. Comparte compromisos precedentes, como el deseo de obtener mejores resultados de aprendizaje y difundir las últimas aportaciones de la geografía académica. La mayor novedad reside en su curiosidad por los complejos procesos que inspiran y guían la actividad educativa. Sus cultivadores, de forma análoga a otros especialistas, contemplan la didáctica de la geografía como un saber intelectual, metodológico, dotado de un vocabulario técnico y conceptos abstractos. En el presente ensayo tratamos de esbozar algunas de las ideas más destacadas que configuran la producción de este saber y algunos de los actores y cambios que ha registrado durante el pasado siglo. PALABRAS CLAVEDidáctica de la geografía, historia de la educación geográfica, construcción del conocimiento,ABSTRACT:The identity of the subject didáctica de la geografía was built up in a discourse that developed throughout the twentieth century. The earliest contributions corresponded to the early years and were

  13. Temporal Variation in the Abundance and Richness of Foliage-Dwelling Ants Mediated by Extrafloral Nectar.

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    Ceres Belchior

    Full Text Available Plants bearing extrafloral nectaries (EFNs are common in the Brazilian cerrado savanna, where climatic conditions having marked seasonality influence arboreal ant fauna organization. These ant-plant interactions have rarely been studied at community level. Here, we tested whether: 1 EFN-bearing plants are more visited by ants than EFN-lacking plants; 2 ant visitation is higher in the rainy season than in dry season; 3 plants producing young leaves are more visited than those lacking young leaves in the rainy season; 4 during the dry season, plants with old leaves and flowers are more visited than plants with young leaves and bare of leaves or flowers; 5 the composition of visiting ant fauna differs between plants with and without EFNs. Field work was done in a cerrado reserve near Uberlândia, MG State, Brazil, along ten transects (total area 3,000 m2, in the rainy (October-January and dry seasons (April-July of 2010-2011. Plants (72 species; 762 individuals were checked three times per season for ant presence. Results showed that 21 species (29% and 266 individuals (35% possessed EFNs. These plants attracted 38 ant species (36 in rainy, 26 in dry season. In the rainy season, plants with EFNs had higher ant abundance/richness than plants without EFNs, but in the dry season, EFN presence did not influence ant visitation. Plant phenology affected ant richness and abundance in different ways: plants with young leaves possessed higher ant richness in the rainy season, but in the dry season ant abundance was higher on plants possessing old leaves or flowers. The species composition of plant-associated ant communities, however, did not differ between plants with and without EFNs in either season. These findings suggest that the effect of EFN presence on a community of plant-visiting ants is context dependent, being conditioned to seasonal variation.

  14. Temporal Variation in the Abundance and Richness of Foliage-Dwelling Ants Mediated by Extrafloral Nectar.

    Science.gov (United States)

    Belchior, Ceres; Sendoya, Sebastián F; Del-Claro, Kleber

    2016-01-01

    Plants bearing extrafloral nectaries (EFNs) are common in the Brazilian cerrado savanna, where climatic conditions having marked seasonality influence arboreal ant fauna organization. These ant-plant interactions have rarely been studied at community level. Here, we tested whether: 1) EFN-bearing plants are more visited by ants than EFN-lacking plants; 2) ant visitation is higher in the rainy season than in dry season; 3) plants producing young leaves are more visited than those lacking young leaves in the rainy season; 4) during the dry season, plants with old leaves and flowers are more visited than plants with young leaves and bare of leaves or flowers; 5) the composition of visiting ant fauna differs between plants with and without EFNs. Field work was done in a cerrado reserve near Uberlândia, MG State, Brazil, along ten transects (total area 3,000 m2), in the rainy (October-January) and dry seasons (April-July) of 2010-2011. Plants (72 species; 762 individuals) were checked three times per season for ant presence. Results showed that 21 species (29%) and 266 individuals (35%) possessed EFNs. These plants attracted 38 ant species (36 in rainy, 26 in dry season). In the rainy season, plants with EFNs had higher ant abundance/richness than plants without EFNs, but in the dry season, EFN presence did not influence ant visitation. Plant phenology affected ant richness and abundance in different ways: plants with young leaves possessed higher ant richness in the rainy season, but in the dry season ant abundance was higher on plants possessing old leaves or flowers. The species composition of plant-associated ant communities, however, did not differ between plants with and without EFNs in either season. These findings suggest that the effect of EFN presence on a community of plant-visiting ants is context dependent, being conditioned to seasonal variation.

  15. Different tolerances of symbiotic and nonsymbiotic ant-plant networks to species extinctions

    Directory of Open Access Journals (Sweden)

    Wesley Dattilo

    2012-12-01

    Full Text Available The knowledge of the mechanisms that shape biodiversity-stability relationships is essential to understand ecological and evolutionary dynamics of interacting species. However, most studies focus only on species loss and ignore the loss of interactions. In this study, I evaluated the topological structure of two different ant-plant networks: symbiotic (ants and myrmecophytes and nonsymbiotic (ants and plants with extrafloral nectaries. Moreover, I also evaluated in both networks the tolerance to plant and ant species extinction using a new approach. For this, I used models based on simulations of cumulative removals of species from the network at random. Both networks were fundamentally different in the interaction and extinction patterns. The symbiotic network was more specialized and less robust to species extinction. On the other hand, the nonsymbiotic network tends to be functionally redundant and more robust to species extinction. The difference for food resource utilization and ant nesting in both ant-plant interactions can explain the observed pattern. In short, I contributed in this manner to our understanding of the biodiversity maintenance and coevolutionary processes in facultative and obligate mutualisms.

  16. Symbiont recognition of mutualistic bacteria by Acromyrmex leaf-cutting ants

    DEFF Research Database (Denmark)

    Zhang, Mingzi; Poulsen, Michael; Currie, Cameron R

    2007-01-01

    Symbiont choice has been proposed to play an important role in shaping many symbiotic relationships, including the fungus-growing ant-microbe mutualism. Over millions of years, fungus-growing ants have defended their fungus gardens from specialized parasites with antibiotics produced...

  17. Volatile chemicals in glands of the carpenter ant, Camponotus ...

    African Journals Online (AJOL)

    Volatile chemicals in glands of the carpenter ant, Camponotus arminius. J.M. Brand, L.V. Mabinya, E.D. Morgan. Abstract. Camponotus arminius is a large black carpenter ant that occurs in tropical and sub-tropical Africa and has extensive foraging trails both in trees and on the ground. Analysis of excised mandibular glands ...

  18. Ants of the Peloponnese, Greece (Hymenoptera: Formicidae

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    Borowiec Lech

    2017-09-01

    Full Text Available This paper relates to material obtained during two field trips to the Peloponnese in 2013 and 2016. With the inclusion of some hitherto unpublished ant material, it gives new records from a total of 92 sampling localities. 129 species (including morphospecies not attributed to any known taxon of ants have been recorded from the Peloponnese (southern Greece, 27 of which have been recorded from this region for the first time. Lasius reginae and 5 other morphospecies attributed only to species complexes are new to Greece.

  19. Density-dependent effects of ants on selection for bumble bee pollination in Polemonium viscosum.

    Science.gov (United States)

    Galen, Candace; Geib, Jennifer C

    2007-05-01

    Mutualisms are commonly exploited by cheater species that usurp rewards without providing reciprocal benefits. Yet most studies of selection between mutualist partners ignore interactions with third species and consequently overlook the impact of cheaters on evolution in the mutualism. Here, we explicitly investigate how the abundance of nectar-thieving ants (cheaters) influences selection in a pollination mutualism between bumble bees and the alpine skypilot, Polemonium viscosum. As suggested in past work with this species, bumble bees accounted for most of the seed production (78% +/- 6% [mean +/- SE]) in our high tundra study population and, in the absence of ants, exerted strong selection for large flowers. We tested for indirect effects of ant abundance on seed set through bumble bee pollination services (pollen delivery and pollen export) and a direct effect through flower damage. Ants reduced seed set per flower by 20% via flower damage. As ant density increased within experimental patches, the rate of flower damage rose, but pollen delivery and export did not vary significantly, showing that indirect effects of increased cheater abundance on pollinator service are negligible in this system. To address how ants affect selection for plant participation in the pollination mutualism we tested the impact of ant abundance on selection for bumble bee-mediated pollination. Results show that the impact of ants on fitness (seed set) accruing under bumble bee pollination is density dependent in P. viscosum. Selection for bumble bee pollination declined with increasing ant abundance in experimental patches, as predicted if cheaters constrain fitness returns of mutualist partner services. We also examined how ant abundance influences selection on flower size, a key component of plant investment in bumble bee pollination. We predicted that direct effects of ants would constrain bumble bee selection for large flowers. However, selection on flower size was significantly

  20. O paciente informado e os saberes médicos: um estudo de etnografia virtual em comunidades de doentes no Facebook

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    André Pereira Neto

    Full Text Available Resumo O mundo presencia atualmente a emergência do “paciente informado”: indivíduo inteirado sobre sua condição de saúde, devido à pesquisa extensa e ao compartilhamento de informação que realiza na internet. Este artigo analisa a seguinte questão: “paciente informado” promove o empoderamento do cidadão ou amplia a dominação dos saberes biomédicos instituídos? Foi realizado estudo exploratório em três grupos on-line no Facebook que reúnem portadores de diabetes, hepatite C e Aids, utilizando a etnografia virtual. Os resultados indicam que há tensões pontuais entre frequentadores de grupoon-line e seus médicos assistentes. É possível que o empoderamento proporcionado pela internet e a validade dos saberes médicos na atualidade não sejam dimensões mutuamente excludentes.

  1. Universidad y edición. Caminos abiertos para el debate y la crítica: textos académicos en América Latina

    Directory of Open Access Journals (Sweden)

    Juan Felipe Córdoba Restrepo

    2014-12-01

    Full Text Available El editor universitario, más allá de editar y distribuir la producción científica de la institución a la cual pertenece, debe dirigirse hacia la exploración y apertura de nuevos espacios y escenarios que propicien y permitan una interlocución dinámica del saber que produce la universidad. Incluso, es necesario aventurarse y proponer a este tipo de editor como uno de los protagonistas de las funciones sustantivas del quehacer universitario: docencia, investigación y extensión. En resumen, es un mediador cultural y es un elemento más de la institución universitaria. El ejercicio de mediador cultural implica estar al frente de los nuevos retos que convoca la divulgación del saber científico en América Latina.

  2. Heavy metal pollution disturbs immune response in wild ant populations

    International Nuclear Information System (INIS)

    Sorvari, Jouni; Rantala, Liisa M.; Rantala, Markus J.; Hakkarainen, Harri; Eeva, Tapio

    2007-01-01

    Concern about the effects of environmental contaminants on immune function in both humans and wildlife is growing and practically nothing is known about this impact on terrestrial invertebrates, even though they are known to easily accumulate pollutants. We studied the effect of industrial heavy metal contamination on immune defense of a free-living wood ant (Formica aquilonia). To find out whether ants show an adapted immune function in a polluted environment, we compared encapsulation responses between local and translocated colonies. Local colonies showed higher heavy metal levels than the translocated ones but the encapsulation response was similar between the two groups, indicating that the immune system of local ants has not adapted to high contamination level. The encapsulation response was elevated in moderate whereas suppressed in high heavy metal levels suggesting higher risk for infections in heavily polluted areas. - Heavy metal pollution affects immune function in ants

  3. Nine novel microsatellite markers for the army ant Simopelta pergandei (subfamily Ponerinae)

    DEFF Research Database (Denmark)

    Kronauer, D.J.C.; Boomsma, J.J.; Pierce, N.E.

    2011-01-01

    Simopelta (subfamily Ponerinae) army ants are specialized predators of other ants in New World tropical forests. Although they show a striking convergence in overall life-history with the well known army ants of the subfamilies Aenictinae, Dorylinae, and Ecitoninae, the genus has been little...... studied. We developed and characterized nine novel microsatellite loci for S. pergandei with 2-8 observed alleles (mean: 5.2) and expected heterozygosities between 0.16 and 0.87 (mean: 0.68). Three of these loci reliably cross-amplified in a second species, S. pentadentata, with 4-8 alleles (mean: 8.......0) and expected heterozygosities between 0.32 and 0.85 (mean: 0.65). These genetic markers will be useful in studying the sociobiology and molecular ecology of Simopelta army ants and in elucidating convergent evolutionary trajectories that have culminated in the army ant lifestyle...

  4. Ants avoid superinfections by performing risk-adjusted sanitary care.

    Science.gov (United States)

    Konrad, Matthias; Pull, Christopher D; Metzler, Sina; Seif, Katharina; Naderlinger, Elisabeth; Grasse, Anna V; Cremer, Sylvia

    2018-03-13

    Being cared for when sick is a benefit of sociality that can reduce disease and improve survival of group members. However, individuals providing care risk contracting infectious diseases themselves. If they contract a low pathogen dose, they may develop low-level infections that do not cause disease but still affect host immunity by either decreasing or increasing the host's vulnerability to subsequent infections. Caring for contagious individuals can thus significantly alter the future disease susceptibility of caregivers. Using ants and their fungal pathogens as a model system, we tested if the altered disease susceptibility of experienced caregivers, in turn, affects their expression of sanitary care behavior. We found that low-level infections contracted during sanitary care had protective or neutral effects on secondary exposure to the same (homologous) pathogen but consistently caused high mortality on superinfection with a different (heterologous) pathogen. In response to this risk, the ants selectively adjusted the expression of their sanitary care. Specifically, the ants performed less grooming and more antimicrobial disinfection when caring for nestmates contaminated with heterologous pathogens compared with homologous ones. By modulating the components of sanitary care in this way the ants acquired less infectious particles of the heterologous pathogens, resulting in reduced superinfection. The performance of risk-adjusted sanitary care reveals the remarkable capacity of ants to react to changes in their disease susceptibility, according to their own infection history and to flexibly adjust collective care to individual risk.

  5. Stigmergic construction and topochemical information shape ant nest architecture.

    Science.gov (United States)

    Khuong, Anaïs; Gautrais, Jacques; Perna, Andrea; Sbaï, Chaker; Combe, Maud; Kuntz, Pascale; Jost, Christian; Theraulaz, Guy

    2016-02-02

    The nests of social insects are not only impressive because of their sheer complexity but also because they are built from individuals whose work is not centrally coordinated. A key question is how groups of insects coordinate their building actions. Here, we use a combination of experimental and modeling approaches to investigate nest construction in the ant Lasius niger. We quantify the construction dynamics and the 3D structures built by ants. Then, we characterize individual behaviors and the interactions of ants with the structures they build. We show that two main interactions are involved in the coordination of building actions: (i) a stigmergic-based interaction that controls the amplification of depositions at some locations and is attributable to a pheromone added by ants to the building material; and (ii) a template-based interaction in which ants use their body size as a cue to control the height at which they start to build a roof from existing pillars. We then develop a 3D stochastic model based on these individual behaviors to analyze the effect of pheromone presence and strength on construction dynamics. We show that the model can quantitatively reproduce key features of construction dynamics, including a large-scale pattern of regularly spaced pillars, the formation and merging of caps over the pillars, and the remodeling of built structures. Finally, our model suggests that the lifetime of the pheromone is a highly influential parameter that controls the growth and form of nest architecture.

  6. The cavity-nest ant Temnothorax crassispinus prefers larger nests.

    Science.gov (United States)

    Mitrus, S

    Colonies of the ant Temnothorax crassispinus inhabit mostly cavities in wood and hollow acorns. Typically in the field, nest sites that can be used by the ant are a limited resource. In a field experiment, it was investigated whether the ants prefer a specific size of nest, when different ones are available. In July 2011, a total of 160 artificial nests were placed in a beech-pine forest. Four artificial nests (pieces of wood with volume cavities, ca 415, 605, 730, and 980 mm 3 , respectively) were located on each square meter of the experimental plot. One year later, shortly before the emergence of new sexuals, the nests were collected. In July 2012, colonies inhabited more frequently bigger nests. Among queenright colonies, the ones which inhabited bigger nests had more workers. However, there was no relationship between volume of nest and number of workers for queenless colonies. Queenright colonies from bigger nests produced more sexual individuals, but there was no correlation between number of workers and sex allocation ratio, or between volume of nest and sex allocation ratio. In a laboratory experiment where ant colonies were kept in 470 and 860 mm 3 nests, larger colonies allocated more energy to produce sexual individuals. The results of this study show the selectivity of T. crassispinus ants regarding the size of nest cavity, and that the nest volume has an impact on life history parameters.

  7. Symmetry breaking on density in escaping ants: experiment and alarm pheromone model.

    Directory of Open Access Journals (Sweden)

    Geng Li

    Full Text Available The symmetry breaking observed in nature is fascinating. This symmetry breaking is observed in both human crowds and ant colonies. In such cases, when escaping from a closed space with two symmetrically located exits, one exit is used more often than the other. Group size and density have been reported as having no significant impact on symmetry breaking, and the alignment rule has been used to model symmetry breaking. Density usually plays important roles in collective behavior. However, density is not well-studied in symmetry breaking, which forms the major basis of this paper. The experiment described in this paper on an ant colony displays an increase then decrease of symmetry breaking versus ant density. This result suggests that a Vicsek-like model with an alignment rule may not be the correct model for escaping ants. Based on biological facts that ants use pheromones to communicate, rather than seeing how other individuals move, we propose a simple yet effective alarm pheromone model. The model results agree well with the experimental outcomes. As a measure, this paper redefines symmetry breaking as the collective asymmetry by deducing the random fluctuations. This research indicates that ants deposit and respond to the alarm pheromone, and the accumulation of this biased information sharing leads to symmetry breaking, which suggests true fundamental rules of collective escape behavior in ants.

  8. The role of ant-tended extrafloral nectaries in the protection and benefit of a Neotropical rainforest tree.

    Science.gov (United States)

    de la Fuente, Marie Ann S; Marquis, Robert J

    1999-02-01

    One possible function of extrafloral nectaries is to attract insects, particularly ants, which defend plants from herbivores. We determined whether ants visiting saplings of the tree Stryphnodendronmicrostachyum (Leguminosae) provide protection (decreased plant damage due to ant molestation or killing of herbivores) and benefit (increased plant growth and reproduction associated with ant presence) to the plant. We compared ant and herbivore abundance, herbivore damage and growth of ant-visited plants and ant-excluded plants grown in sun and shade microhabitats of a 6-ha plantation in Costa Rica over a 7-month period. Results show that ants provided protection to plants not by reducing herbivore numbers but by molesting herbivores. Ants also reduced the incidence of pathogen attack on leaves. Protection was greater in the shade than in the sun, probably due to lower herbivore attack in the sun. Protection was also variable within sun and shade habitats, and this variability appeared to be related to variable ant visitation. Results also indicate that ant presence benefits the plant: ant-visited plants grew significantly more in height than ant-excluded plants. The cultivation of ants may serve as an important natural biological control in tropical forestry and agroforestry systems, where increased plant density can otherwise lead to increased herbivore attack.

  9. Daily estimates of the migrating tide and zonal mean temperature in the mesosphere and lower thermosphere derived from SABER data

    Science.gov (United States)

    Ortland, David A.

    2017-04-01

    Satellites provide a global view of the structure in the fields that they measure. In the mesosphere and lower thermosphere, the dominant features in these fields at low zonal wave number are contained in the zonal mean, quasi-stationary planetary waves, and tide components. Due to the nature of the satellite sampling pattern, stationary, diurnal, and semidiurnal components are aliased and spectral methods are typically unable to separate the aliased waves over short time periods. This paper presents a data processing scheme that is able to recover the daily structure of these waves and the zonal mean state. The method is validated by using simulated data constructed from a mechanistic model, and then applied to Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) temperature measurements. The migrating diurnal tide extracted from SABER temperatures for 2009 has a seasonal variability with peak amplitude (20 K at 95 km) in February and March and minimum amplitude (less than 5 K at 95 km) in early June and early December. Higher frequency variability includes a change in vertical structure and amplitude during the major stratospheric warming in January. The migrating semidiurnal tide extracted from SABER has variability on a monthly time scale during January through March, minimum amplitude in April, and largest steady amplitudes from May through September. Modeling experiments were performed that show that much of the variability on seasonal time scales in the migrating tides is due to changes in the mean flow structure and the superposition of the tidal responses to water vapor heating in the troposphere and ozone heating in the stratosphere and lower mesosphere.

  10. Host-ant specificity of endangered large blue butterflies (Phengaris spp., Lepidoptera: Lycaenidae) in Japan.

    Science.gov (United States)

    Ueda, Shouhei; Komatsu, Takashi; Itino, Takao; Arai, Ryusuke; Sakamoto, Hironori

    2016-11-03

    Large blue butterflies, Phengaris (Maculinea), are an important focus of endangered-species conservation in Eurasia. Later-instar Phengaris caterpillars live in Myrmica ant nests and exploit the ant colony's resources, and they are specialized to specific host-ant species. For example, local extinction of P. arion in the U. K. is thought to have been due to the replacement of its host-ant species with a less-suitable congener, as a result of changes in habitat. In Japan, Myrmica kotokui hosts P. teleius and P. arionides caterpillars. We recently showed, however, that the morphological species M. kotokui actually comprises four genetic clades. Therefore, to determine to which group of ants the hosts of these two Japanese Phengaris species belong, we used mitochondrial COI-barcoding of M. kotokui specimens from colonies in the habitats of P. teleius and P. arionides to identify the ant clade actually parasitized by the caterpillars of each species. We found that these two butterfly species parasitize different ant clades within M. kotokui.

  11. Polarized light use in the nocturnal bull ant, Myrmecia midas.

    Science.gov (United States)

    Freas, Cody A; Narendra, Ajay; Lemesle, Corentin; Cheng, Ken

    2017-08-01

    Solitary foraging ants have a navigational toolkit, which includes the use of both terrestrial and celestial visual cues, allowing individuals to successfully pilot between food sources and their nest. One such celestial cue is the polarization pattern in the overhead sky. Here, we explore the use of polarized light during outbound and inbound journeys and with different home vectors in the nocturnal bull ant, Myrmecia midas . We tested foragers on both portions of the foraging trip by rotating the overhead polarization pattern by ±45°. Both outbound and inbound foragers responded to the polarized light change, but the extent to which they responded to the rotation varied. Outbound ants, both close to and further from the nest, compensated for the change in the overhead e-vector by about half of the manipulation, suggesting that outbound ants choose a compromise heading between the celestial and terrestrial compass cues. However, ants returning home compensated for the change in the e-vector by about half of the manipulation when the remaining home vector was short (1-2 m) and by more than half of the manipulation when the remaining vector was long (more than 4 m). We report these findings and discuss why weighting on polarization cues change in different contexts.

  12. Evidence of the Lower Thermospheric Winter-to-Summer Circulation From SABER CO2 Observations

    Science.gov (United States)

    Qian, Liying; Burns, Alan; Yue, Jia

    2017-10-01

    Numerical studies have shown that there is a lower thermospheric winter-to-summer circulation that is driven by wave dissipation and that it plays a significant role in trace gas distributions in the mesosphere and lower thermosphere, and in the composition of the thermosphere. However, the characteristics of this circulation are poorly known. Direct observations of it are difficult, but it leaves clear signatures in tracer distributions. The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) onboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics satellite has obtained CO2 concentration from 2002 to present. This data set, combined with simulations by the Whole Atmosphere Community Climate Model, provides an unprecedented opportunity to infer the morphology of this circulation in both the summer and winter hemispheres. Our study show that there exists a maximum vertical gradient of CO2 at summer high latitudes, driven by the convergence of the upwelling of the mesospheric circulation and the downwelling of the lower thermospheric circulation; in the winter hemisphere, the maximum vertical gradient of CO2 is located at a higher altitude, driven by the convergence of the upwelling of the lower thermospheric circulation and the downwelling of the solar-driven thermospheric circulation; the bottom of the lower thermospheric circulation is located between 95 km and 100 km, and it has a vertical extent of 10 km. Analysis of the SABER CO2 and temperature at summer high latitudes showed that the bottom of this circulation is consistently higher than the mesopause height by 10 km.

  13. Autonomous Agents on Expedition: Humans and Progenitor Ants and Planetary Exploration

    Science.gov (United States)

    Rilee, M. L.; Clark, P. E.; Curtis, S. A.; Truszkowski, W. F.

    2002-01-01

    The Autonomous Nano-Technology Swarm (ANTS) is an advanced mission architecture based on a social insect analog of many specialized spacecraft working together to achieve mission goals. The principal mission concept driving the ANTS architecture is a Main Belt Asteroid Survey in the 2020s that will involve a thousand or more nano-technology enabled, artificially intelligent, autonomous pico-spacecraft (architecture. High level, mission-oriented behaviors are to be managed by a control / communications layer of the swarm, whereas common low level functions required of all spacecraft, e.g. attitude control and guidance and navigation, are handled autonomically on each spacecraft. At the higher levels of mission planning and social interaction deliberative techniques are to be used. For the asteroid survey, ANTS acts as a large community of cooperative agents while for precursor missions there arises the intriguing possibility of Progenitor ANTS and humans acting together as agents. For optimal efficiency and responsiveness for individual spacecraft at the lowest levels of control we have been studying control methods based on nonlinear dynamical systems. We describe the critically important autonomous control architecture of the ANTS mission concept and a sequence of partial implementations that feature increasingly autonomous behaviors. The scientific and engineering roles that these Progenitor ANTS could play in human missions or remote missions with near real time human interactions, particularly to the Moon and Mars, will be discussed.

  14. Nonintegrated Host Association of Myrmecophilus tetramorii, a Specialist Myrmecophilous Ant Cricket (Orthoptera: Myrmecophilidae

    Directory of Open Access Journals (Sweden)

    Takashi Komatsu

    2013-01-01

    Full Text Available Myrmecophilus ant crickets (Orthoptera: Myrmecophilidae are typical ant guests. In Japan, about 10 species are recognized on the basis of morphological and molecular phylogenetic frameworks. Some of these species have restricted host ranges and behave intimately toward their host ant species (i.e., they are host specialist. We focused on one species, M. tetramorii, which uses the myrmicine ant Tetramorium tsushimae as its main host. All but one M. tetramorii individuals were collected specifically from nests of T. tsushimae in the field. However, behavioral observation showed that all individuals used in the experiment received hostile reactions from the host ants. There were no signs of intimate behaviors such as grooming of hosts or receipt of mouth-to-mouth feeding from hosts, which are seen in some host-specialist Myrmecophilus species among obligate host-ant species. Therefore, it may be that M. tetramorii is the species that is specialized to exploit the host by means other than chemical integration.

  15. Ecologia de saberes: a experiência do diálogo entre conhecimento científico e conhecimento tradicional na comunidade quilombola da Rocinha

    Directory of Open Access Journals (Sweden)

    Luciana Marinho SANTOS

    2014-06-01

    Full Text Available Este artigo tem como finalidade refletir sobre o diálogo entre o conhecimento científico moderno e o conhecimento construído pelos povos e comunidades tradicionais à luz do conceito “ecologia de saberes” de Boaventura Sousa Santos. O estudo é fruto de uma experiência do projeto de educação ambiental realizado em uma comunidade quilombola, tendo as plantas medicinais como elemento do conhecimento tradicional e sua relação com a medicina convencional na comunidade. Tais questões nos possibilitaram abordar, em uma perspectiva teórica, os elementos característicos da ecologia de saberes, apontando para a importância do diálogo entre os diversos saberes, especificamente, o conhecimento tradicional e o conhecimento científico.

  16. Are ant assemblages of Brazilian veredas characterised by location or habitat type?

    Science.gov (United States)

    Costa-Milanez, C B; Lourenço-Silva, G; Castro, P T A; Majer, J D; Ribeiro, S P

    2014-02-01

    Wetland areas in the Brazilian Cerrado, known as "veredas", represent ecosystems formed on sandy soils with high concentrations of peat, and are responsible for the recharge of aquiferous reservoirs. They are currently under threat by various human activities, most notably the clearing of vegetation for Eucalyptus plantations. Despite their ecological importance and high conservation value, little is known about the actual effects of human disturbance on the animal community. To assess how habitat within different veredas, and plantations surrounding them affect ant assemblages, we selected four independent vereda locations, two being impacted by Eucalyptus monoculture (one younger and one mature plantation) and two controls, where the wetland was surrounded by cerrado vegetation. Ant sampling was conducted in May 2010 (dry season) using three complementary methods, namely baits, pitfall traps, and hand collection, in the wetland and in the surrounding habitats. A total of 7,575 ants were sampled, belonging to seven subfamilies, 32 genera and 124 species. Ant species richness and abundance did not differ between vereda locations, but did between the habitats. When impacted by the monoculture, ant species richness and abundance decreased in wetlands, but were less affected in the cerrado habitat. Ant species composition differed between the three habitats and between vereda locations. Eucalyptus plantations had an ant species composition defined by high dominance of Pheidole sp. and Solenopsis invicta, while natural habitats were defined by Camponotus and Crematogaster species. Atta sexdens was strictly confined to native habitats of non-impacted "veredas". Eucalyptus monocultures require high quantities of water in the early stages, which may have caused a decrease in groundwater level in the wetland, allowing hypogeic ants such as Labidus praedator to colonise this habitat.

  17. Effect of irradiation on queen survivorship and reproduction in the invasive fire ant Solenopsis invicta,(Hymenoptera: Formicidae) and a generic phytosanitary irradiation treatment for ants

    Science.gov (United States)

    Ants are common hitchhiker pests on traded agricultural commodities that could be controlled by postharvest irradiation treatment. We studied radiation tolerance in queens of the red imported fire ant Solenopsis invicta Buren to determine the dose sufficient for its control. Virgin or fertile queens...

  18. Ant Colony Optimization ACO For The Traveling Salesman Problem TSP Using Partitioning

    Directory of Open Access Journals (Sweden)

    Alok Bajpai

    2015-08-01

    Full Text Available Abstract An ant colony optimization is a technique which was introduced in 1990s and which can be applied to a variety of discrete combinatorial optimization problem and to continuous optimization. The ACO algorithm is simulated with the foraging behavior of the real ants to find the incremental solution constructions and to realize a pheromone laying-and-following mechanism. This pheromone is the indirect communication among the ants. In this paper we introduces the partitioning technique based on the divide and conquer strategy for the traveling salesman problem which is one of the most important combinatorial problem in which the original problem is partitioned into the group of sub problems. And then we apply the ant colony algorithm using candidate list strategy for each smaller sub problems. After that by applying the local optimization and combining the sub problems to find the good solution for the original problem by improving the exploration efficiency of the ants. At the end of this paper we have also be presented the comparison of result with the normal ant colony system for finding the optimal solution to the traveling salesman problem.

  19. Using ant-behavior-based simulation model AntWeb to improve website organization

    Science.gov (United States)

    Li, Weigang; Pinheiro Dib, Marcos V.; Teles, Wesley M.; Morais de Andrade, Vlaudemir; Alves de Melo, Alba C. M.; Cariolano, Judas T.

    2002-03-01

    Some web usage mining algorithms showed the potential application to find the difference among the organizations expected by visitors to the website. However, there are still no efficient method and criterion for a web administrator to measure the performance of the modification. In this paper, we developed an AntWeb, a model inspired by ants' behavior to simulate the sequence of visiting the website, in order to measure the efficient of the web structure. We implemented a web usage mining algorithm using backtrack to the intranet website of the Politec Informatic Ltd., Brazil. We defined throughput (the number of visitors to reach their target pages per time unit relates to the total number of visitors) as an index to measure the website's performance. We also used the link in a web page to represent the effect of visitors' pheromone trails. For every modification in the website organization, for example, putting a link from the expected location to the target object, the simulation reported the value of throughput as a quick answer about this modification. The experiment showed the stability of our simulation model, and a positive modification to the intranet website of the Politec.

  20. Development of a Bait System for the Pharaoh's Ant, Monomorium ...

    African Journals Online (AJOL)

    The infestation of the Pharaoh's ant, Monomorium pharaonis L. is widespread and, sometimes, very serious in homes, hospitals, restaurants, factories, etc. People are helpless because effective baited traps are not available locally, and little has been done locally to develop effective control strategies for these ants.