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Sample records for ants bender peep

  1. Pop Culture Peeps

    Science.gov (United States)

    Kruszewski, Julie; Fontes, Kris

    2008-01-01

    In this article, the authors present a classroom activity called Pop Culture Peep. In this particular activity, students are required to first research famous artists and/or famous artworks to have an image to use as a reference. Students then plan out how they would decorate the Peep, deciding what materials they would use to create the Peep in…

  2. 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....

  3. Professor Peep Veski meie meenutustes

    Index Scriptorium Estoniae

    2014-01-01

    Mälestusi Tartu Ülikooli Farmaatsia instituudi juhatajast Peep Veskist jagavad: Eve-Irene Lepist, Urve Paaver, Karin Kogermann, Kristian Semjonov, Jaak Koppel, Kristin Raudsepp, Imre Klebovich, Filiz Hincal, A. Atilla Hincal ja Elmar Arak

  4. Professor Peep Veski meie meenutustes

    Index Scriptorium Estoniae

    2014-01-01

    Mälestusi Tartu Ülikooli Farmaatsia instituudi juhatajast Peep Veskist jagavad: Eve-Irene Lepist, Urve Paaver, Karin Kogermann, Kristian Semjonov, Jaak Koppel, Kristin Raudsepp, Imre Klebovich, Filiz Hincal, A. Atilla Hincal ja Elmar Arak

  5. Helend Peep on teleteatri legend

    Index Scriptorium Estoniae

    2005-01-01

    17. dets. möödub 50 aastat Eesti Televisiooni esimesest teatriõhtust, milleks oli Vanemuise lavastus "Viirastused", autor A. Jakobson ja lavastaja E. Kaidu, peaosas H. Peep. H. Peebul oli roll selles lavastuses ka Kuressaare teatris 1939. a., kus tema partneriks oli luuletaja G. Suitsu tütar, näitleja ja luuletaja M. Suits

  6. The Neopuff's PEEP valve is flow sensitive.

    LENUS (Irish Health Repository)

    Hawkes, Colin Patrick

    2012-01-31

    AIM: The current recommendation in setting up the Neopuff is to use a gas flow of 5-15 L\\/min. We investigated if the sensitivity of the positive end expiratory pressure (PEEP) valve varies at different flow rates within this range. METHODS: Five Neopuffs were set up to provide a PEEP of 5 cm H(2) O. The number of clockwise revolutions to complete occlusion of the PEEP valve and the mean and range of pressures at each quarter clockwise revolution were recorded at gas flow rates between 5 and 15 L\\/min. Results: At 5, 10 and 15 L\\/min, 0.5, 1.7 and 3.4 full clockwise rotations were required to completely occlude the PEEP valve, and pressures rose from 5 to 11.4, 18.4 and 21.5 cm H(2) O, respectively. At a flow rate of 5 L\\/min, half a rotation of the PEEP dial resulted in a rise in PEEP from 5 to 11.4cm H(2) O. At 10 L\\/min, half a rotation resulted in a rise from 5 to 7.7cm H(2) O, and at 15 L\\/min PEEP rose from 5 to 6.8cm H(2) O. CONCLUSION: Users of the Neopuff should be aware that the PEEP valve is more sensitive at lower flow rates and that half a rotation of the dial at 5 L\\/min gas flow can more than double the PEEP.

  7. Kuus visiooni haldusreformist Eestis ja Lätis / Väino Tõemets, Peep Aru, Jaan Õunapuu ... [jt.

    Index Scriptorium Estoniae

    2009-01-01

    Oma visiooni esitavad siseministeeriumi kohaliku omavalitsuse ja regionaalhadluse osak. juhataja Väino Tõemets, parlamendiliige, endine regionaalminister Peep Aru, Tartumaa Omavalitsuste Liidu tegevjuht Jaan Õunapuu, Jõgevamaa Omavalitsuste Liidu tegevdirektor Ants Orgulas, Liepa vallavanem Andris Rancâns ja Cesise rajooni tegevjuht Mâris Niklass

  8. Peep Aaviksoo : Minu äri 10 käsku / Peep Aaviksoo

    Index Scriptorium Estoniae

    Aaviksoo, Peep, 1956-

    2008-01-01

    Paljudes suurfirmades töötanud ja sellega hindamatu kogemuse saanud ärimees jagab kogemusi, kuidas olla ettevõtluses edukas. Hetkel tegeleb Peep Aaviksoo Eesti investorite raha paigutamisega IPC Investmenti kaudu Rumeenia kinnisvarasse. Lisa: Peep Aaviksoo (tegevus). Vahendanud Kaileen Mägi

  9. Educational Implications of the Bender.

    Science.gov (United States)

    Petti, Michael

    1988-01-01

    Examples of diagnostic formulations of the "Bender Visual-Motor Gestalt" are outlined and their instructional implications are delineated. The difficulties in paper and pencil copying of geometric designs focus primarily on: separation and overlapping of figures, repetition of design elements, pencil grip, visual perceptions, pattern reversals,…

  10. Performance of remanent supermirror benders

    Energy Technology Data Exchange (ETDEWEB)

    Boeni, P.; Clemens, D.; Horisberger, M.; Rubio, D.; Tixier, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Hahn, W. [ISIS (United Kingdom)

    1997-09-01

    Polarising supermirrors composed of magnetic and non-magnetic layers have been deposited on thin glass sheets by means of reactive DC-magnetron sputtering. Benders that are composed of such glass have an excellent transmission and can be used for polarising neutrons in zero field. (author) 3 figs., 1 tab., 2 refs.

  11. Peep Reinas ei taha enam olla Res Publica liige / Peep Reinas ; interv. Argo Soolep

    Index Scriptorium Estoniae

    Reinas, Peep

    2004-01-01

    Ilmunud ka: Severnoje Poberezhje, 16. sept. 2004, lk. 2. Peep Reinas arvati välja Res Publica nimekirjast kohaliku võimu tasandil Keskerakonnaga tehtud koostöö tõttu. Tallinna linnakohtu otsusest

  12. The Neopuff's PEEP valve is flow sensitive.

    LENUS (Irish Health Repository)

    Hawkes, Colin Patrick

    2011-03-01

    The current recommendation in setting up the Neopuff is to use a gas flow of 5-15 L\\/min. We investigated if the sensitivity of the positive end expiratory pressure (PEEP) valve varies at different flow rates within this range.

  13. Effect of external PEEP in patients under controlled mechanical ventilation with an auto-PEEP of 5 cmH2O or higher.

    Science.gov (United States)

    Natalini, Giuseppe; Tuzzo, Daniele; Rosano, Antonio; Testa, Marco; Grazioli, Michele; Pennestrì, Vincenzo; Amodeo, Guido; Berruto, Francesco; Fiorillo, Marialinda; Peratoner, Alberto; Tinnirello, Andrea; Filippini, Matteo; Marsilia, Paolo F; Minelli, Cosetta; Bernardini, Achille

    2016-12-01

    In some patients with auto-positive end-expiratory pressure (auto-PEEP), application of PEEP lower than auto-PEEP maintains a constant total PEEP, therefore reducing the inspiratory threshold load without detrimental cardiovascular or respiratory effects. We refer to these patients as "complete PEEP-absorbers." Conversely, adverse effects of PEEP application could occur in patients with auto-PEEP when the total PEEP rises as a consequence. From a pathophysiological perspective, all subjects with flow limitation are expected to be "complete PEEP-absorbers," whereas PEEP should increase total PEEP in all other patients. This study aimed to empirically assess the extent to which flow limitation alone explains a "complete PEEP-absorber" behavior (i.e., absence of further hyperinflation with PEEP), and to identify other factors associated with it. One hundred patients with auto-PEEP of at least 5 cmH2O at zero end-expiratory pressure (ZEEP) during controlled mechanical ventilation were enrolled. Total PEEP (i.e., end-expiratory plateau pressure) was measured both at ZEEP and after applied PEEP equal to 80 % of auto-PEEP measured at ZEEP. All measurements were repeated three times, and the average value was used for analysis. Forty-seven percent of the patients suffered from chronic pulmonary disease and 52 % from acute pulmonary disease; 61 % showed flow limitation at ZEEP, assessed by manual compression of the abdomen. The mean total PEEP was 7 ± 2 cmH2O at ZEEP and 9 ± 2 cmH2O after the application of PEEP (p auto-PEEP can be accurately predicted at the bedside by measuring the respiratory rate and observing the flow-volume loop during manual compression of the abdomen.

  14. Linnapea Peep Aru : looduskaitsjad pole osanud asja korrektselt ajada / Peep Aru ; interv. Rannar Raba

    Index Scriptorium Estoniae

    Aru, Peep, 1953-

    2006-01-01

    Üle-eelmisel nädalal avaldas looduskaitse seltsi Viljandi osakonna esimees Jaak Jaaku arvamust, et palju räägitud loodusmaja tegemine on venima hakanud peaasjalikult sellepärast, et linnavalitsus pole mõtte arendamisega kaasa tulnud. Selgitab linnapea Peep Aru

  15. Model-based PEEP optimisation in mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Chiew Yeong Shiong

    2011-12-01

    Full Text Available Abstract Background Acute Respiratory Distress Syndrome (ARDS patients require mechanical ventilation (MV for breathing support. Patient-specific PEEP is encouraged for treating different patients but there is no well established method in optimal PEEP selection. Methods A study of 10 patients diagnosed with ALI/ARDS whom underwent recruitment manoeuvre is carried out. Airway pressure and flow data are used to identify patient-specific constant lung elastance (Elung and time-variant dynamic lung elastance (Edrs at each PEEP level (increments of 5cmH2O, for a single compartment linear lung model using integral-based methods. Optimal PEEP is estimated using Elung versus PEEP, Edrs-Pressure curve and Edrs Area at minimum elastance (maximum compliance and the inflection of the curves (diminishing return. Results are compared to clinically selected PEEP values. The trials and use of the data were approved by the New Zealand South Island Regional Ethics Committee. Results Median absolute percentage fitting error to the data when estimating time-variant Edrs is 0.9% (IQR = 0.5-2.4 and 5.6% [IQR: 1.8-11.3] when estimating constant Elung. Both Elung and Edrs decrease with PEEP to a minimum, before rising, and indicating potential over-inflation. Median Edrs over all patients across all PEEP values was 32.2 cmH2O/l [IQR: 26.1-46.6], reflecting the heterogeneity of ALI/ARDS patients, and their response to PEEP, that complicates standard approaches to PEEP selection. All Edrs-Pressure curves have a clear inflection point before minimum Edrs, making PEEP selection straightforward. Model-based selected PEEP using the proposed metrics were higher than clinically selected values in 7/10 cases. Conclusion Continuous monitoring of the patient-specific Elung and Edrs and minimally invasive PEEP titration provide a unique, patient-specific and physiologically relevant metric to optimize PEEP selection with minimal disruption of MV therapy.

  16. Factor- Analytic Study of Performance on the Bender-Gestalt

    Science.gov (United States)

    Haynes, Jack R.

    1970-01-01

    College students were given the 16 Personality Factor Questionnaire, the Guilford Zimmerman Spatial Orientation and Spatial Visualization Tests, and the Bender Gestalt. Analyses revealed that personality characteristics were related to Bender performance and that the Bender was not measuring a unitary dimension of behavior. (Author)

  17. New studies of adults' responses to the Bender Gestalt.

    Science.gov (United States)

    Murray, J B

    2001-02-01

    The Bender-Gestalt test originated in 1936 with Lauretta Bender for evaluating perceptual and motor development of children 4 to 11 yr. old. Koppitz (1964) developed a scoring system for the test. Lacks (1984) contributed normative data for testing adults. Seven studies since Lacks' which have contributed to normative data of adults' responses to the Bender-Gestalt are reviewed here.

  18. Peep Põldsamm lõi kampa Skype'i loojatega

    Index Scriptorium Estoniae

    2008-01-01

    Peep Põldsamm asus juhtima Modesat Communications OÜd, mille omanik on Skype'i kaasasutajatele kuuluv investeerimisfirma Ambient Sound Investments. Modesat plaanib saavutada modemitehnoloogia rahvusvahelisel turul viieprotsendilise turuosa. Vt. samas: Põldsamm: olen uute äride ülesehitaja

  19. Peep Vain - the Best-known Training Guru in the Baltics = Peep Vain - Baltikumi tuntuim koolitusguru / Marit Sillavee

    Index Scriptorium Estoniae

    Sillavee, Marit

    2006-01-01

    Koolitusfirma Vain & Partnerid osaniku Peep Vainu karjäärist ja koolitajatööst. Vt. samas: Spiritual Trainer toTop Sportsmen = Tippsportlaste vaimutreener ; Lead Billing in Estonia's Highest-Grossing Documentary = Eesti edukaima dokfilmi peategelane

  20. Peep Vain - the Best-known Training Guru in the Baltics = Peep Vain - Baltikumi tuntuim koolitusguru / Marit Sillavee

    Index Scriptorium Estoniae

    Sillavee, Marit

    2006-01-01

    Koolitusfirma Vain & Partnerid osaniku Peep Vainu karjäärist ja koolitajatööst. Vt. samas: Spiritual Trainer toTop Sportsmen = Tippsportlaste vaimutreener ; Lead Billing in Estonia's Highest-Grossing Documentary = Eesti edukaima dokfilmi peategelane

  1. 90 aastat Katseasjanduse nõukogu asutamisest / Ants Bender

    Index Scriptorium Estoniae

    Bender, Ants, 1945-

    2013-01-01

    Katseasjanduse nõukogu ülesanne oli uurimistöö teaduslik ja tehniline edendamine. Nõukogu kinnitas asutuste katsekavad, esitas taotlused katsetööde finantseerimiseks, vaatas läbi ja kinnitas uurimistööde aruanded ning korraldas katseandmete publitseerimist. 1938. a moodustati Katseasjanduse nõukogu asemel Põllumajandusliku Uurimise ja Katseasjanduse Komitee. Katseasjanduse nõukogu taasloodi 2002. a

  2. Lauretta Bender on autism: a review.

    Science.gov (United States)

    Faretra, G

    1979-01-01

    Lauretta Bender, internationally known as one of the pioneers in the field of child psychiatry, has written extensively on autism and other forms of childhood disturbance. This paper reviews and analyzes the development of her theories on autism, especially as it relates to childhood schizophrenia. Bender believes that the condition is one of the manifestations of schizophrenia occurring in earliest childhood. This review traces, through her writings and through personal contact, the development and elaboration of this view, and discusses influences on her work of Schilder, Gesell and others.

  3. Bender Gestalt Performance of Normal Older Adults.

    Science.gov (United States)

    Lacks, Patricia; Storandt, Martha

    1982-01-01

    Provides normative data on the Bender Gestalt Test (BGT) with a sample of 334 normal older adults. Showed that these older adults do not perform on the BGT in a manner that can be called brain damaged. Use of the cut-off score developed with younger persons appears appropriate. (Author)

  4. Reading Retardation and Bender Gestalt Performance

    Science.gov (United States)

    Binkley, M. Edward; Maggart, William

    1974-01-01

    Compared two groups of children know to be poor readers, those with adequate perceptual functioning and those without, to determine what inadequate perceptual functioning is related to the severity of the reading and adjustment problems. Inadequate Bender performance was related to a more severe reading problem. (Author/PC)

  5. A Graphic Analysis Bender Gestalt Test.

    Science.gov (United States)

    Hilgert, Larry D.

    1985-01-01

    Bender Gestalt Test data from 60 severely emotionally handicapped and 60 normal children were computer digitized and scored traditionally. Reliability results from comparison of analysis techniques favored computer approach; criterion-related validity was unsuccessful for both scoring methods; and concurrent validity results indicated limited…

  6. Junior High Norms for the Bender Gestalt.

    Science.gov (United States)

    Grow, Richard T.

    1980-01-01

    Junior high students were tested to supply normative data supporting the Bender Gestalt. Subject's performance was not significantly related to sex or occupation of the family bread winner. These variables do not have to be controlled for in norming visual motor tests at the junior high level. (Author)

  7. Lauretta Bender's Contribution to Understanding Language Disorders.

    Science.gov (United States)

    Silver, Archie A.

    1989-01-01

    Lauretta Bender's experiences as a bright child struggling with specific learning problems and her subsequent work in language disorders are described. Her recognition of the biological nature of a group of learning disorders for which there was no clinical evidence of structural damage to the central nervous system is emphasized. (JDD)

  8. Secure Human-Computer Identification against Peeping Attacks (SecHCI): A Survey

    OpenAIRE

    Li, SJ; Shum, HY

    2003-01-01

    This paper focuses on human-computer identification systems against peeping attacks, in which adversaries can observe (and even control) interactions between humans (provers) and computers (verifiers). Real cases on peeping attacks were reported by Ross J. Anderson ten years before. Fixed passwords are insecure to peeping attacks since adversaries can simply replay the observed passwords. Some identification techniques can be used to defeat peeping attacks, but auxiliary devices must be used ...

  9. Bender-Gestalt reproduction times for retarded adults.

    Science.gov (United States)

    Andert, J N; Hustak, T L; Dinning, W D

    1978-10-01

    Examined the length of time required by retarded adults to complete the Bender-Gestalt test with a sample of 241 test administrations. In order to provide for normative comparisons among retarded adults, descriptive data are presented on the Bender reproduction times of adults in three AAMD ranges of retardation based on WAIS IQs and two ranges based on Stanford-Binet IQs. Negative correlations were found between the length of Bender times and the degree of retardation. The duration of Bender times was correlated positively with the number of errors in reproduction as measured by the Koppitz developmental scoring system.

  10. English for lawyers / Liina Soobik ; [preface: Peep Pruks

    Index Scriptorium Estoniae

    Soobik, Liina, 1955-

    2001-01-01

    Kasutatud tekstide autorid: Peep Pruks, Merit-Ene Ilja, Ilona Nurmela, Kristi Raba, Andreas Kangur, Raul Narits, Peeter Roosma, Kalle Merusk, Maret Altnurme, Jaan Ginter, Aare Tark, Norman Aas, Lasse Lehis, Hannes Veinla, Jaan Sootak, Eerik Kergandberg, Paul Varul, Jaanus Ots, Urve Liin, Irene Kull, Merle Muda, Gaabriel Tavits, Andres Vutt, Kadri Siibak, Ellen Ridaste, Heiki Pisuke, Andrus Siibak

  11. DE BENDER ( SEGUNDA VERSIÓN

    Directory of Open Access Journals (Sweden)

    CÉSAR MERINO SOTO

    2013-01-01

    Full Text Available Hace algunos años, se ha publicado el nuevo Test Gestáltico de Bender, segunda versión (Ben- der-II. Esta nueva versión usa el Sistema de Calificación Global (SCG para obtener los pun- tajes, que enfatiza la reproducción exacta de los diseños; junto con otros cambios estructurales, consiste en la mayor modificación realizada al Test de Bender para evaluar la habilidad visomo- tora en varias etapas del desarrollo humano. Pero aún hay pocas investigaciones que han estudiado su funcionamiento psicométrico en muestras his- panas y especialmente el error de medición en el procedimiento de la calificación. Se investigó el efecto de la variabilidad de la calificación del nuevo Bender-II sobre su validez de constructo con una medida de inteligencia. Se administraron el Bender-II y el Test Breve de In- teligencia de Kaufman (K-BIT a 60 niños prees- colares, y tres calificadores calificaron las figu- ras reproducidas mediante procedimientos es- tandarizados y el SCG. El análisis comparó las correlaciones obtenidas por cada calificador en- tre los puntajes del Bender-II y del K-BIT. Se ha- lló que la variabilidad de los puntajes provenien- te de la interpretación del SCG afectó mode- radamente las correlaciones con el puntaje total y de las subescalas del K-BIT. Un calificador fue menos confiable y sus puntajes mostraron al me- nos 5% menos variancia compartida al compa- rarlo con los otros calificadores. Se concluye que la interpretación de la validez se puede dis- torsionar aun cuando el error de medición es moderado pues interaccionan con otras fuentes de error. Esto sugiere que se debe garantizar un buen acuerdo en la calificación de pruebas que requieran juicio.

  12. Is There Any Association between PEEP and Upper Extremity DVT?

    Directory of Open Access Journals (Sweden)

    Farah Al-Saffar

    2015-01-01

    Full Text Available Background. We hypothesized that positive end-exploratory pressure (PEEP may promote venous stasis in the upper extremities and predispose to upper extremity deep vein thrombosis (UEDVT. Methods. We performed a retrospective case control study of medical intensive care unit patients who required mechanical ventilation (MV for >72 hours and underwent duplex ultrasound of their upper veins for suspected DVT between January 2011 and December 2013. Results. UEDVT was found in 32 (28.5% of 112 patients. Nineteen (67.8% had a central venous catheter on the same side. The mean ± SD duration of MV was 13.2±9.5 days. Average PEEP was 7.13±2.97 cm H2O. Average PEEP was ≥10 cm H2O in 23 (20.5% patients. Congestive heart failure (CHF significantly increased the odds of UEDVT (OR 4.53, 95% CI 1.13–18.11; P=0.03 whereas longer duration of MV (≥13 vs. <13 days significantly reduced it (OR 0.29, 95% CI 0.11–0.8; P=0.02. Morbid obesity showed a trend towards significance (OR 3.82, 95% CI 0.95–15.4; P=0.06. Neither PEEP nor any of the other analyzed predictors was associated with UEDVT. Conclusions. There is no association between PEEP and UEDVT. CHF may predispose to UEDVT whereas the risk of UEDVT declines with longer duration of MV.

  13. Bender Gestalt Recall: Memory Measure or Intelligence Estimate?

    Science.gov (United States)

    Armentrout, James A.

    1976-01-01

    WAIS subtset standard scores, IQ scores, and factorial deviation quotients were correlated with Bender Gestalt recall scores for 111 vocational rehabilitation clients. Results found that the Bender recall task could not classify Ss as to general intelligence level with greater accuracy than could be obtained with the WAIS Vocabulary subtest alone.…

  14. Bender Gestalt Signs as Indicants of Conceptual Impulsivity

    Science.gov (United States)

    Brannigan, Gary G.; And Others

    1978-01-01

    Sixty children were individually administered the Matching Familiar Figures Test and the Bender Gestalt Test. A significant relationship was found between errors on the Bender Gestalt Test and impulsivity. Specifically, increased or decreased loops, change in angulation, loops for circles, and circles for dots or dots for circles were all…

  15. Two Aspects of Scorer Reliability in the Bender Gestalt Test

    Science.gov (United States)

    Morsbach, Gisela; And Others

    1975-01-01

    This study investigated (a) interscorer reliability of the Bender-Gestalt Test by using more than one person to score the same test protocols; and (b) rate-rerate reliability of the Bender-Gestalt Test after a half-year interval. (Author)

  16. Two modes of administration of the Bender Visual-Motor Gestalt Test to kindergarten children.

    Science.gov (United States)

    Caskey, W E; Larson, G L

    1977-12-01

    Using Otis-Lennon IQs 104 kindergarten children were paired and divided into two groups. The first was administered a group Bender test based on transparencies of the Bender designs and 10 to 14 days later the standard individual Bender Test. The second group was administered the Bender tests in reverse order. A significant correlation was found between Koppitz scores from the group and the individual Bender scores. It is suggested that the group Bender test might be used as a screening device without significant loss of information on a later administration of the individual Bender test.

  17. Modeling of a Dielectric Elastomer Bender Actuator

    Directory of Open Access Journals (Sweden)

    Paul White

    2014-07-01

    Full Text Available The current smallest self-contained modular robot uses a shape memory alloy, which is inherently inefficient, slow and difficult to control. We present the design, fabrication and demonstration of a module based on dielectric elastomer actuation. The module uses a pair of bowtie dielectric elastomer actuators in an agonist-antagonist configuration and is seven times smaller than previously demonstrated. In addition, we present an intuitive model for the bowtie configuration that predicts the performance with experimental verification. Based on this model and the experimental analysis, we address the theoretical limitations and advantages of this antagonistic bender design relative to other dielectric elastomer actuators.

  18. Honey Ants.

    Science.gov (United States)

    Conway, John R.

    1984-01-01

    Provides background information on honey ants. These ants are found in dry or desert regions of North America, Africa, and Australia. Also provides a list of activities using local species of ants. (JN)

  19. Lugejate valik : Peep Vain on parim / Marko Liibak

    Index Scriptorium Estoniae

    Liibak, Marko

    2007-01-01

    Aripaev.ee ja ajaleht Äripäev korraldasid lugejate seas küsitluse, mille käigus valiti Eesti parimaks koolitajaks Vain & Partnerite omanik ning koolituskonsultant Peep Vain. Teisele kohale tuli koolitaja, juhtimiskonsultant ja nõustaja ning Tallinn Ülikooli kliinilise psühholoogia professor Mare Pork. Järgnesid Ülo Vihma, Indrek Saul, Tiit Valm, Mihkel Pärjamäe ning Alexander Kotchubei

  20. Lugejate valik : Peep Vain on parim / Marko Liibak

    Index Scriptorium Estoniae

    Liibak, Marko

    2007-01-01

    Aripaev.ee ja ajaleht Äripäev korraldasid lugejate seas küsitluse, mille käigus valiti Eesti parimaks koolitajaks Vain & Partnerite omanik ning koolituskonsultant Peep Vain. Teisele kohale tuli koolitaja, juhtimiskonsultant ja nõustaja ning Tallinn Ülikooli kliinilise psühholoogia professor Mare Pork. Järgnesid Ülo Vihma, Indrek Saul, Tiit Valm, Mihkel Pärjamäe ning Alexander Kotchubei

  1. Analytical modeling of sandwich beam for piezoelectric bender elements

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Piezoelectric bender elements are widely used as electromechanical sensors and actuators. An analytical sandwich beam model for piezoelectric bender elements was developed based on the first-order shear deformation theory (FSDT), which assumes a single rotation angle for the whole cross-section and a quadratic distribution function for coupled electric potential in piezoelectric layers, and corrects the effect of transverse shear strain on the electric displacement integration. Free vibration analysis of simplysupported bender elements was carried out and the numerical results showed that, solutions of the present model for various thickness-to-length ratios are compared well with the exact two-dimensional solutions, which presents an efficient and accurate model for analyzing dynamic electromechanical responses of bender elements.

  2. Split radius-form blocks for tube benders

    Science.gov (United States)

    Lange, D. R.; Seiple, C. W.

    1970-01-01

    Two-piece, radius-form block permits accurate forming and removing of parts with more than a 180 degree bend. Tube bender can shape flexible metal tubing in applications dealing with plumbing, heating, and pressure transmission lines.

  3. Reliability of two common PEEP-generating devices used in neonatal resuscitation.

    Science.gov (United States)

    Kelm, M; Proquitté, H; Schmalisch, G; Roehr, C C

    2009-12-01

    Approximately 15% of neonates require respiratory support at birth, the demand of which increases with decreasing gestational age. Positive end-expiratory pressure (PEEP) stabilizes the airways and improves both pulmonary functional residual capacity and compliance. Self-inflating bags, which can be used with and without a PEEP-valve, are most commonly used for neonatal resuscitation, pressure limited T-piece resuscitators are becoming increasingly popular. The aim of the study was to investigate the reliability of PEEP provision of both systems. An intubated, leak free mannequin (equivalent to 1 kg neonate, pulmonary compliance 0.2 ml*cmH (2)O (-1)) was used for testing both devices. Eleven PEEP-valves attached to a 240 ml self-inflating bag and 5 T-piece resuscitators were investigated. Provision of a PEEP of 5 cmH (2)O (gas flow of 8l/min) at manual ventilation at breaths 40/min was investigated. Data were recorded using a standard pneumotachograph. Only 1/11 PEEP-valves provided a PEEP of 5 cmH (2)O (mean (SD) 2.95 (1.82) cmH (2)O, CV 0.62%), in 5/11 (45%) PEEP was valves produced a PEEP below 0.3 cmH (2)O. All T-piece resuscitators provided a PEEP >5 cmH (2)O (mean 5.59 (0.32) cmH (2)O, CV 0.06%). Significant differences in individual performance per device (pvalves, neonatologists should check the equipment regarding the reliability of PEEP provision. (c) Georg Thieme Verlag KG Stuttgart New York.

  4. Hyperdynamic sepsis modifies a PEEP-mediated redistribution in organ blood flows

    Energy Technology Data Exchange (ETDEWEB)

    Bersten, A.D.; Gnidec, A.A.; Rutledge, F.S.; Sibbald, W.J. (Univ. of Western Ontario, London (Canada))

    1990-05-01

    Changes in organ blood flow (Q) produced by 20 cm H2O positive end-expiratory pressure (PEEP) were measured before and after the induction of hyperdynamic sepsis in nine unanesthetized sheep. During the baseline nonseptic study, PEEP was associated with a 9% fall in thermodilution-measured systemic Q, although arterial perfusing pressures were unaffected. Concurrently, microsphere-derived Q was maintained to the brain and heart, but fell to liver, spleen, pancreas, kidney, large intestine, and gastrocnemius. Twenty-four to 36 h after cecal ligation and perforation, a pre-PEEP septic study demonstrated an increase in all of the cardiac index (CI) and systemic O2 delivery when compared with the nonseptic study, whereas whole-body O2 extraction was depressed. Although PEEP depressed systemic Q during the septic study to a greater extent than during the nonseptic study (p less than 0.02), absolute organ Q fell only to pancreas, liver, and spleen. Relative to the simultaneous fall in the CI, Q to some splanchnic organs was not depressed by PEEP to the same magnitude in the septic as in the nonseptic study. When an infusion of Ringer's lactate subsequently restored systemic Q to pre-PEEP septic levels, individual flows that had been depressed by PEEP were not restored. Furthermore, Q-kidney continued to fall, such that the postfluid Q-kidney (-19%) was significantly less than was demonstrated in the pre-PEEP septic study. We postulate that differences noted in the distribution of organ Q between the nonseptic and hyperdynamic septic studies after the application of PEEP were secondary to the vasculopathy of sepsis and/or an alteration in the function of specific organ microcirculations. However, these data do not address whether the changes in organ Q distribution after a PEEP-mediated depression in systemic Q during sepsis significantly restricted tissue DO2.

  5. Voyeuristi alla finestra: Peeping Tom, dalla leggenda al cinema

    Directory of Open Access Journals (Sweden)

    Laura Staiano

    2015-01-01

    Full Text Available This essay deals with voyeuristic attitudes and ʹscopic powerʹ, i.e. the power to gaze at forbidden things and people without being seen. Indeed, its object par excellence coincides with female nakedness, while its subject is an invisible masculinity, which takes delight in looking.The paper is based on a study of the Anglo-Saxon legend of Lady Godiva and it is strictly connected with the subject of my dissertation in progress – metaphorical and physical blindness in 18th century French literature (since several voyeurs got blind because of their instincts and desires. Lady Godiva’s voyeur, called Peeping Tom, is struck blind for having looked out of his window and seen the noblewoman riding naked. This legend has inspired many artists in different fields, and nowadays its heroine is very famous and venerated. In particular, this essay focuses on the relation between this legend and compulsive looking (or scopophilia in two renowned films, Rear Window by Alfred Hitchcock, and Peeping Tom by Michael Powell.

  6. Information Processing Components of Koppitz Errors on the Bender Visual-Motor Gestalt Test.

    Science.gov (United States)

    Blaha, John; And Others

    1979-01-01

    The relative importance of different cognitive subprocesses in Bender performance was studied with Black middle-class first graders. Results suggest that the Bender owes much of its clinical validity to loadings across all stages of human information processing. Kagan's hypothesis on conceptual tempo in Bender performance is also analyzed. (SJL)

  7. Reassessment of Inferring Personality Traits from Bender-Gestalt Drawing Styles.

    Science.gov (United States)

    Holmes, Cooper B.; And Others

    1984-01-01

    Assessed patients with closure difficulty on the Bender-Gestalt (N=50) and patients with edging tendencies on the Bender-Gestalt (N=50) for possible personality traits associated with those drawing styles. Results did not support using clients' Bender-Gestalt drawing style as a basis for inferring personality traits. (LLL)

  8. Respiratory mechanics in COPD patients who failed non-invasive ventilation: role of intrinsic PEEP.

    Science.gov (United States)

    Antonaglia, Vittorio; Ferluga, Massimo; Capitanio, Guido; Lucangelo, Umberto; Piller, Fulvia; Roman-Pognuz, Erik; Biancardi, Bruno; Caggegi, Giuseppe Davide; Zin, Walter A

    2012-10-15

    Non-invasive positive pressure ventilation (NPPV) is the first choice to treat exacerbations in COPD patients. NPPV can fail owing to different causes related to gas exchange impairment (RF group) or intolerance (INT group). To assess if the respiratory mechanical properties and the ratio between the dynamic and static intrinsic positive end-expiratory pressure (PEEP(i),dyn/PEEP(i),stat), reflecting lung mechanical inequalities, were different between groups, 29 COPD patients who failed NPPV (15 RF and 14 INT) were studied, early after the application of invasive ventilation. Blood gas analysis, clinical status, and mechanical properties were measured. pH was higher in INT patients before intubation (p<0.001). PEEP(i),dyn/PEEP(i),stat was found higher in INT group with (p=0.021) and without PEEP (ZEEP, p<0.01). PEEP(i),dyn/PEEP(i),stat was exponentially associated with the duration of NPPV in INT group (p=0.011). INT and RF patients had similar impairment of respiratory system resistance and elastance.

  9. Obituary: David Fulmer Bender, 1913-2004

    Science.gov (United States)

    Miller, Sylvia L.

    2004-12-01

    David Fulmer Bender died in San Diego, California, on 13 September 2004, at the age of 91. His heart stopped suddenly while he was dancing. His pioneering work in establishing comprehensive, computer-accessible ephemerides of asteroids and comets found many applications, including the first-ever visit to an asteroid, Gaspra, by an interplanetary spacecraft. Dave was born in Reno, Nevada, on 10 February 1913, to Homer Charles Bender and Susan Bowers Bender. The family moved to Spokane, Washington, while Dave was very young. His father was a civil engineer and a graduate of MIT, who helped design bridges and dams throughout the Northwest, including the Grand Coolie Dam. Dave had a brother, Phillip (now deceased), who was one year younger. Advancing rapidly in the Spokane school system, Dave finished high school when he was 15 years old. At 16 he moved to Pasadena, California, and began his studies at the California Institute of Technology (Caltech). In addition to pursuing his course work, he was active in track and football, a tendency toward physical exercise that stayed with him for the rest of his life. It was probably during these years that Dave heard a lecture by Albert Einstein, as mentioned to colleagues many years later. Dave received a BS degree in physics in 1933, an MS in 1934, and a PhD in 1937, all from Caltech. His dissertation was entitled, "The Index of Refraction of Air in the Photographic Infrared." During his sophomore year he found his way to Pomona College in Claremont, California, where he met his future wife, Elizabeth Boyden at a social gathering. They were married in 1935. Dave's academic career spanned the years from 1937 to 1970, initially at Louisiana State University, Vanderbilt University, and then Fisk. As a life-long pacifist and conscientious objector, Dave served alternate duty during World War II. In 1946 he joined the faculty of the physics department at Whittier College in California, where he became the department chair and

  10. PEEP Role in ICU and Operating Room: From Pathophysiology to Clinical Practice

    Directory of Open Access Journals (Sweden)

    M. Vargas

    2014-01-01

    Full Text Available Positive end expiratory pressure (PEEP may prevent cyclic opening and collapsing alveoli in acute respiratory distress syndrome (ARDS patients, but it may play a role also in general anesthesia. This review is organized in two sections. The first one reports the pathophysiological effect of PEEP on thoracic pressure and hemodynamic and cerebral perfusion pressure. The second section summarizes the knowledge and evidence of the use of PEEP in general anesthesia and intensive care. More specifically, for intensive care this review refers to ARDS and traumatic brain injured patients.

  11. Modeling of sensor function for piezoelectric bender elements

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An analytical sandwich beam model for piezoelectric bender elements is derived based on the first-order shear deformation theory (FSDT), which assumes a single rotation angle for the whole cross-section and a quadratic distribution for coupled electric potential in piezoelectric layers. Shear coefficient is introduced to correct the effect of transverse shear strain on shear force and the electric displacement integration. Static and free vibration analyses of simply-supported bender elements are carried out for the sensor function. The results illustrate the high accuracy of the present model compared with the exact 2D solutions.

  12. Raudna põhikooli spordihoone Heimtalis / Peep Jänes, Signe Stokas, Gildas Stokas...[jt.

    Index Scriptorium Estoniae

    2009-01-01

    Ill.: situatsiooniplaan, soklikorruse plaan, aksonomeetria., 7 vaadet; fotod: Allan Alajaan, Arne Maasik; peaprojekteerija: K & H; muinsuskaitse eritingimused: A. Kulbach. Peep Jänes pälvis EK arhitektuuri sihtkapitali aastapreemia 2008

  13. Peep Aaviksoo kukutas EMT-kesksus / Jaan Männik ; interv. Vallo Toomet

    Index Scriptorium Estoniae

    Männik, Jaan, 1945-

    2003-01-01

    EMT nõukogu esimees ja Eesti Telekomi juhatuse esimees Jaan Männik vastab küsimustele, mis on seotud Peep Aaviksoo lahkumisega Eesti Mobiiltelefoni juhi kohalt. Vt. samas: Aaviksoo selgitab lahkumise põhjusi. Peep Aaviksoo kiri. Kommenteerivad Radiolinja Eesti juhatuse esimees Sami Seppänen, Tele2 Eesti juhatuse esimees Üllar Jaaksoo, Ühispanga analüütik Sven Kunsing

  14. Sociocultural Factors and Bender Visual Motor Gestalt Performance.

    Science.gov (United States)

    Sapp, Gary L.

    The Bender Visual Motor Gestalt Test (BG), a test of visual-motor integration, is a screening device used to investigate school-related factors that may produce poor academic achievement and learning disabilities. Because BG test stimuli are not obviously related to classroom content, and because BG scores are frequently offered as evidence of…

  15. Bender Test Recall in Children: An Unreliable Test.

    Science.gov (United States)

    Rogers, Dan L.

    1980-01-01

    To assess the utility and reliability of Bender test recall in children, 304 children (ages 5 through 14) were individually administered the copy and recall phases using Koppitz's directions. The recall phase was judged to be of doubtful utility in assessing intellectual functioning in children. (Author/SJL)

  16. A Benders approach for the constrained minimum break problem

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus Vinther; Trick, Michael

    2007-01-01

    This paper presents a hybrid IP/CP algorithm for designing a double round robin schedule with a minimal number of breaks. Both mirrored and non-mirrored schedules with and without place constraints are considered. The algorithm uses Benders cuts to obtain feasible home-away pattern sets in few...

  17. Johan Kõpu pärand on mitmekülgne / Peep Pillak

    Index Scriptorium Estoniae

    Pillak, Peep

    2008-01-01

    rets. rmt.: Rohtmets, Priit. Rektor Johan Kõpp / toimetaja Mart Orav; resümeede tõlge: saksa keelde Reet Bender, inglise keelde Saskia Kangro, vene keelde A & A Lingua; kujundus Kalle Toompere. Tallinn : Aasta Raamat, 2007. 144 lk.

  18. Johan Kõpu pärand on mitmekülgne / Peep Pillak

    Index Scriptorium Estoniae

    Pillak, Peep

    2008-01-01

    rets. rmt.: Rohtmets, Priit. Rektor Johan Kõpp / toimetaja Mart Orav; resümeede tõlge: saksa keelde Reet Bender, inglise keelde Saskia Kangro, vene keelde A & A Lingua; kujundus Kalle Toompere. Tallinn : Aasta Raamat, 2007. 144 lk.

  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......, 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. Solving a reverse supply chain design problem by improved Benders decomposition schemes.

    OpenAIRE

    Santibanez-Gonzalez, Ernesto Del Rosario; Diabat, Ali

    2013-01-01

    In this paper we propose improved Benders decomposition schemes for solving a remanufacturing supply chain design problem (RSCP). We introduce a set of valid inequalities in order to improve the quality of the lower bound and also to accelerate the convergence of the classical Benders algorithm. We also derive quasi Pareto-optimal cuts for improving convergence and propose a Benders decomposition scheme to solve our RSCP problem. Computational experiments for randomly generated networks of up...

  1. Struggling Ants

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Some of China’s college graduates are barely scraping by The village of Tangjialing, 20 km north of down town Beijing, was thrust into the public consciousness in November. Publishers that month released a book titled Ants

  2. Comparison of the Developmental Test of Visual-Motor Integration and the Bender-Gestalt test.

    Science.gov (United States)

    Brown, M J

    1977-12-01

    The Developmental Test of Visual-motor Integration (Beery) and the Bender-Gestalt test (Bender) were administered to 44 second-grade children. Developmental age scores (Koppitz scoring) and age equivalents (Beery) were compared. The correlation of .43 between Bender (Koppitz scoring) and Beery scores was moderate but statistically significant. A t test for dependent groups indicated a significant difference between the means on the Bender and Beery tests. These results confirm that neither test should be utilized as the sole indicator of visual-motor perception.

  3. Differential functioning of Bender Visual-Motor Gestalt Test items.

    Science.gov (United States)

    Sisto, Fermino Fernandes; Dos Santos, Acácia Aparecida Angeli; Noronha, Ana Paula Porto

    2010-02-01

    Differential Item Functioning (DIF) refers to items that do not function the same way for comparable members of different groups. The present study focuses on analyzing and classifying sex-related differential item functioning in the Bender Visual-Motor Gestalt Test. Subjects were 1,052 children attending public schools (513 boys, 539 girls, ages 6-10 years). The protocols were scored using the Bender Graduated Scoring System, which evaluates only the distortion criterion using the Rasch logistic response model. The scoring system fit the Rasch model, although two items were found to be biased by sex. When analyzing differential functioning of items for boys and girls separately, the number of differentially functioning items was equal.

  4. Olen saanud nelikümmend aastat jälgida eesti filmi arengut... : Dokumentalist Peep Puks eile ja täna / Peep Puks, Jaan Ruus, Vaike Mesila ... [jt.

    Index Scriptorium Estoniae

    2011-01-01

    Peep Puksi mõtteid, lisaks kolleegid - filmidirektor V. Mesila, filmikriitik J. Ruus, monteerija K.-E. Rääk ja operaator A. Vilu Peep Puksist ja tema filmidest, üles kirjutanud Mart Taevere. Artikli lõpus P.Puksi filmograafia

  5. Bender-Gestalt Test correlates of prognosis in Unipolar Depression

    Directory of Open Access Journals (Sweden)

    Mr. Anand Prakash MPhil

    2010-07-01

    Full Text Available The Bender-Gestalt test (B-G test was administered to examine its prognostic implications in an Ethiopian sample with unipolar depression. Total 30 patients with moderate level of depression were included in study and their time taken was compared against the performance on the B-G test. Finally, a significant difference was found between time taken and Z-scores of the test supporting the prognostic value of this test in unipolar depression.

  6. PEEP-ZEEP technique: cardiorespiratory repercussions in mechanically ventilated patients submitted to a coronary artery bypass graft surgery

    Directory of Open Access Journals (Sweden)

    Auler José

    2011-09-01

    Full Text Available Abstract Background The PEEP-ZEEP technique is previously described as a lung inflation through a positive pressure enhancement at the end of expiration (PEEP, followed by rapid lung deflation with an abrupt reduction in the PEEP to 0 cmH2O (ZEEP, associated to a manual bilateral thoracic compression. Aim To analyze PEEP-ZEEP technique's repercussions on the cardio-respiratory system in immediate postoperative artery graft bypass patients. Methods 15 patients submitted to a coronary artery bypass graft surgery (CABG were enrolled prospectively, before, 10 minutes and 30 minutes after the technique. Patients were curarized, intubated, and mechanically ventilated. To perform PEEP-ZEEP technique, saline solution was instilled into their orotracheal tube than the patient was reconnected to the ventilator. Afterwards, the PEEP was increased to 15 cmH2O throughout 5 ventilatory cycles and than the PEEP was rapidly reduced to 0 cmH2O along with manual bilateral thoracic compression. At the end of the procedure, tracheal suction was accomplished. Results The inspiratory peak and plateau pressures increased during the procedure (p Conclusion The PEEP-ZEEP technique seems to be safe, without alterations on hemodynamic variables, produces elevated expiratory flow and seems to be an alternative technique for the removal of bronchial secretions in patients submitted to a CABG.

  7. Ant Farm

    OpenAIRE

    2012-01-01

    Publié à l’occasion de l’exposition d’Ant Farm au Frac Centre du 12 au 23 décembre 2007, ce très beau catalogue, qui fait état des dix ans de création du collectif californien, propose un nombre important de documents iconographiques, de notices et de textes concernant leurs différents projets. Fondé en 1968 par Doug Michels et Chip Lord, rejoints par la suite par Curtis Schreier, Hudson Marquez, Douglas Hurr et d’autres encore, le collectif Ant Farm a marqué les esprits par quelques œuvres s...

  8. Reliability of the Advanced Psychodiagnostic Interpretation (API) Scoring System for the Bender Gestalt.

    Science.gov (United States)

    Aucone, Ernest J.; Raphael, Alan J.; Golden, Charles J.; Espe-Pfeifer, Patricia; Seldon, Jen; Pospisil, Tanya; Dornheim, Liane; Proctor-Weber, Zoe; Calabria, Michael

    1999-01-01

    Assessed the interrater reliability of the revised Advanced Psychodiagnostic Interpretation (API) (A. Raphael and C. Golden, 1998) scoring system for the Bender Gestalt Test (L. Bender, 1938). Agreement across nine raters exceeded 90% for each of three clinical protocols, and kappa statistics indicated good interrater reliability. (SLD)

  9. Relationship of Bender Memory to Achievement in Arithmetic by First Graders.

    Science.gov (United States)

    Snyder, Robert T.; And Others

    1980-01-01

    Arithmetic and reading achievement scores of 84 children were correlated with power and precision of Bender Memory using the Bender Visual Memory Technique (BVMT). Of the 20 correlations, 16 were significant. Support for recommended use of the BVMT as a screening instrument for early assessment of arithmetic skill is provided. (Author/SJL)

  10. Multiple Sources of Test Bias on the WISC-R and Bender-Gestalt Test.

    Science.gov (United States)

    Oakland, Thomas; Feigenbaum, David

    1979-01-01

    Assessed test bias on the Wechsler Intelligence Test for Children-Revised (WISC-R) and Bender-Gestalt. On the Bender, evidence of bias was infrequent and irregular. On the WISC-R, group differences were most discernible for age, sex, family structure, and race. Consistent patterns of bias were not apparent among comparison groups. (Author)

  11. Comparison of the Minnesota Percepto-Diagnostic Test and Bender-Gestalt: Relationship with Achievement Criteria.

    Science.gov (United States)

    Fuller, Gerald B.; Wallbrown, Fred H.

    1983-01-01

    Compared the Bender Gestalt (BD) and Minnesota Percepto-Diagnostic Test (MPD) in predicting academic achievement for younger children (N=69). Results suggested that the MPD is more sensitive than the Bender in identifying visual-motor perception areas of achievement performance problems. (LLL)

  12. Correlations of the WRAT and PIAT Reading Recognition Subtest Scores with the VMI And Bender Gestalt.

    Science.gov (United States)

    Vance, Booney; Gore, William V.

    The relationship between word recognition subtests of the Wide Range Achievement Test and Peabody Individual Achievement Test with Bender-Gestalt and the Berry-Buktencia Test of Visual Motor Integration was examined with 27 children (7-14 years old) referred for psychological services. The Bender and Berry tests are among the most popular…

  13. Predicting Reading and Arithmetic Achievement by Using Bender Gestalt and Visual Memory Technique.

    Science.gov (United States)

    Rust, James O.; And Others

    1982-01-01

    First grade students were administered a screening battery that included the Otis-Lennon Mental Ability Test, the Metropolitan Readiness Test, the Bender Gestalt Test, and the Visual Memory Technique. Stepwise regression equations revealed that the Bender Gestalt Test significantly increased the predictive power of the test battery. (FL)

  14. Scaled Score Transformations of Bender Gestalt Expectancy Levels for Young Children

    Science.gov (United States)

    Hartlage, Lawrence C.; Lucas, David G.

    1971-01-01

    The present study was aimed at developing a method for the transformation of Bender performance into scaled score equivalents and at testing the validity of such scaled score equivalents. The use of scaled scores permits a more direct comparison between Bender performance and performance on measures of intellectual ability. (Author)

  15. Bender-Gestalt Emotional Indicators and Acting-Out Behavior in Young Children.

    Science.gov (United States)

    Trahan, Donald; Stricklin, Ann

    1979-01-01

    The relationship between 15 emotional indicators on the Bender Gestalt Test and the acting out behavior of 93 children, ages 5 to 12, as rated by their teachers, was investigated. Use of the Bender as a projective measure was seriously questioned. The ten-item behavioral rating scale is appended. (MH)

  16. Analysis of bender element test interpretation using the discrete element method

    NARCIS (Netherlands)

    O’Donovan, J.; O’Sullivan, C.; Marketos, G.; Muir Wood, D.

    2015-01-01

    While bender element testing is now well-established as a laboratory technique to determine soil stiffness, a robust technique to interpret the data remains elusive. A discrete element method (DEM) model of a face-centred cubic packing of uniform spheres was created to simulate bender element tests

  17. Correlations of the WRAT and PIAT Reading Recognition Subtest Scores with the VMI And Bender Gestalt.

    Science.gov (United States)

    Vance, Booney; Gore, William V.

    The relationship between word recognition subtests of the Wide Range Achievement Test and Peabody Individual Achievement Test with Bender-Gestalt and the Berry-Buktencia Test of Visual Motor Integration was examined with 27 children (7-14 years old) referred for psychological services. The Bender and Berry tests are among the most popular…

  18. The Stability of Koppitz Scores on the Bender-Gestalt for Reading Disabled Children.

    Science.gov (United States)

    Wallbrown, Fred H.; Fremont, Theodore

    1980-01-01

    Findings support Koppitz's assertion that the total error score for the Bender Gestalt Test is stable and reliable. Working time is a relatively stable dimension of Bender performance, which may be of value in assessment activities. Perseveration and integration should not be used in differential diagnosis. (Author)

  19. The Koppitz Developmental Scoring System for the Bender-Gestalt: Is It Developmental?

    Science.gov (United States)

    Taylor, Ronald L.; And Others

    1984-01-01

    Investigated the developmental aspects of the Koppitz scoring system with 652 children who took the Bender Motor Gestalt Test. Scores were fitted to various developmental curves by computer. Results indicated only 35 percent of the Bender test performance variance was accounted for by age. (JAC)

  20. Comparison of Native American Navajo Bender-Gestalt Performance with Koppitz and Sompa Norms.

    Science.gov (United States)

    Moore, Clay L.; Zarske, John A.

    1984-01-01

    Compared Bender-Gestalt performance of 452 Navajo children with 1974 Koppitz and System of Multicultural Pluralistic Assessment norms (SOMPA), and investigated the use of the Bender-Gestalt for diagnosing learning disabilities. Results suggested the Koppitz and SOMPA White norms may be useful in psychological assessment of Navajo children. (JAC)

  1. Surface-mounted bender elements for measuring horizontal shear wave velocity of soils

    Institute of Scientific and Technical Information of China (English)

    Yan-guo ZHOU; Yun-min CHEN; Yoshiharu ASAKA; Tohru ABE

    2008-01-01

    The bender element testing features its in-plane directivity,which allows using bender elements to measure the shear wave velocities in a wider range of in-plane configurations besides the standard tip-to-tip alignment.This paper proposed a novel bender element testing technique for measuring the horizontal shear wave velocity of soils,where the bender elements are surface-mounted and the axes of the source and receiver elements are parallel to each other.The preliminary tests performed on model ground of silica sand showed that,by properly determining the travel distance and time of the shear waves,the surface-mounted bender elements can perform as accurately as the conventional "tip-to-tip" configuration.Potentially,the present system provides a promising nondestructive tool for characterizing geomaterials and site conditions both in laboratory and in the fields.

  2. Respiratory inductive plethysmography accuracy at varying PEEP levels and degrees of acute lung injury

    NARCIS (Netherlands)

    D.G. Markhorst (Dick); M.A. van Van Gestel (Miriam); H.R. van Genderingen (Huibert); J.J. Haitsma (Jack); B.F. Lachmann (Burkhard); A.J. van Vught (Adrianus)

    2006-01-01

    textabstractBackground and objective: This study was performed to assess the accuracy of respiratory inductive plethysmographic (RIP) estimated lung volume changes at varying positive end-expiratory pressures (PEEP) during different degrees of acute respiratory failure. Methods: Measurements of insp

  3. Raudna põhikooli spordihoone Heimtalis = Raudna School Sports Facility in Heimtali / Peep Jänes

    Index Scriptorium Estoniae

    Jänes, Peep, 1936-

    2009-01-01

    2008. a. valminud spordihoonest, mille autor on Peep Jänes, projekteerija GS-Dis, sisekujundajad Signe ja Gildardas Stokas. Spordihoone rajati 1860. a. ehitatud mõisa ringtalli välismüüri sisealale ja restaureeriti ajalooline ringmüür

  4. Raudna põhikooli spordihoone Heimtalis = Raudna School Sports Facility in Heimtali / Peep Jänes

    Index Scriptorium Estoniae

    Jänes, Peep, 1936-

    2009-01-01

    2008. a. valminud spordihoonest, mille autor on Peep Jänes, projekteerija GS-Dis, sisekujundajad Signe ja Gildardas Stokas. Spordihoone rajati 1860. a. ehitatud mõisa ringtalli välismüüri sisealale ja restaureeriti ajalooline ringmüür

  5. The validity of the Bender-Gestalt emotional indicators.

    Science.gov (United States)

    Rossini, E D; Kaspar, J C

    1987-01-01

    We evaluated the concurrent validity of the revised Bender-Gestalt emotional indicators (Koppitz, 1975) among three groups of children in the 7- to 10-year age range: adjustment disorder, behavior disorder, and normal control. The concurrent validity of the emotional indicators total score was demonstrated. Notably, with the developmental level controlled, both clinical groups produced significantly more emotional indicators than the control group, although the two clinical groups could not be differentiated. Nominal-data analyses of the 13 individual emotional indicators indicated that three specific indicators (confused order, large size, boxed figures) possessed validity as pathognomonic signs. We discuss issues concerning the use of the emotional indicators in clinical practice.

  6. Design and Scheduling of Microgrids using Benders Decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Nagarajan, Adarsh; Ayyanar, Raja

    2016-11-21

    The distribution feeder laterals in a distribution feeder with relatively high PV generation as compared to the load can be operated as microgrids to achieve reliability, power quality and economic benefits. However, renewable resources are intermittent and stochastic in nature. A novel approach for sizing and scheduling an energy storage system and microturbine for reliable operation of microgrids is proposed. The size and schedule of an energy storage system and microturbine are determined using Benders' decomposition, considering PV generation as a stochastic resource.

  7. The Southern California Sensory Integration Tests (Ayres) and the Bender Gestalt: a correlative study.

    Science.gov (United States)

    Kimball, J G

    1977-01-01

    The Southern California Sensory Integration Tests (SCSIT) and the Bender Gestalt are two measures used to evaluate children with suspected perceptual-motor deficits. Since these tests are used primarily by two groups of professionals, occupational therapists and psychologists, it was thought that studying the correlations between these two tests might help psychologists to know which children needed to be referred to an occupational therapist for sensory integrative evaluation, and might help the occupational therapist to understand the psychologist's use of the Bender Gestalt. The use of the Bender by the occupational therapist as a screening device for sensory integrative dysfunction was also investigated. The SCSIT and Bender were given to 26 children with suspected sensory integrative dysfunction. Scores on the Bender were found to be predictive of grouped scores on the Form and Space Perception and Praxis-Tactile sections of the SCSIT, but not of the Postural and Bilateral Integration section. It was concluded that when the Bender is used as a screening device for sensory integrative dysfunction, some measure of postural mechanisms must be included. Correlations between the Bender and individual tests of the SCSIT were also studied.

  8. The Ants Have It!

    Science.gov (United States)

    Daugherty, Belinda

    2001-01-01

    Uses the GEMS guide, "Ants at Home Underground", to explore the life of ants and teach about them in a classroom setting. The activity applies students' knowledge of ants and students learn about ant colonies, what ants eat, and how they live. (SAH)

  9. The Ants Have It!

    Science.gov (United States)

    Daugherty, Belinda

    2001-01-01

    Uses the GEMS guide, "Ants at Home Underground", to explore the life of ants and teach about them in a classroom setting. The activity applies students' knowledge of ants and students learn about ant colonies, what ants eat, and how they live. (SAH)

  10. Mis on muutunud noorte huvis huvitegevuse vastu? / Toomas-Vahur Lihtmaa, Peep Tobreluts, Annely Köster ... [jt.

    Index Scriptorium Estoniae

    2012-01-01

    Küsimusele vastasid Tallinna kunstikooli direktor Toomas-Vahur Lihtmaa, Viljandi huvikooli loodusringi juhendaja Peep Tobreluts, Sally stuudio juhataja Annely Köster, Abja tehnikaringi juhendaja Tarmo Raba, Kullo huvikeskuse automodellismi huviringi juhendaja Mait Murumäe

  11. Fire Ant Allergy

    Science.gov (United States)

    ... Treatments ▸ Library ▸ Allergy Library ▸ Fire ant allergy Share | Fire Ant Allergy This article has been reviewed by Thanai Pongdee, MD, FAAAAI Fire ants are a stinging insect typically found in ...

  12. 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 ...

  13. Differential Effect of Amphetamine Optical Isomers on Bender Gestalt Performance of the Minimally Brain Dysfunctioned

    Science.gov (United States)

    Arnold, L. Eugene; And Others

    1978-01-01

    The differential effect of amphetamine optical isomers on Bender Gestalt performance was examined in 31 hyperkinetic minimally brain dysfunctioned children between the ages of 4 and 12 years, using a double-blind Latin-square crossover comparison. (Author)

  14. An Item Analysis and Validity Investigation of Bender Visual Motor Gestalt Test Score Items

    Science.gov (United States)

    Lambert, Nadine M.

    1971-01-01

    This investigation attempted to demonstrate the utility of standard item analysis procedures for selecting the most reliable and valid items for scoring Bender Visual Motor Gestalt Test test records. (Author)

  15. Comparison of Bender-Gestalt and WISC Correlations for Puerto Rican, White and Negro Children

    Science.gov (United States)

    Marmorale, Ann M.; Brown, Fred

    1975-01-01

    This study investigated whether a positive relationship between Bender-Gestalt performance and intelligence test scores would be found for Puerto Rican children and, as well, the generalizability of previous results obtained with Negro children. (Author/RK)

  16. Bender Gestalt Signs and Anti-Social Acting Out Tendencies in Adolescents

    Science.gov (United States)

    Brannigan, Gary G.; Benowity, Martin L.

    1975-01-01

    This study explores the relationship between performance on the Bender-Gestalt test and antisocial acting out tendencies in adolescents. Results indicate that uneven figure size and exaggerated curvature are the best indicators of antisocial acting out tendencies. (Author)

  17. The Bender-Gestalt Test in Differential Diagnosis of Adolescents with Learning Difficulties

    Science.gov (United States)

    Mordock, John B.; and others

    1968-01-01

    Attempt to assess efficiency of Haine and Koppitz scoring systems with Bender-Gestalt in ability to differentiate between brain-damaged and other young people in a residential treatment center did not prove useful. (Author/CJ)

  18. State of the evidence: mechanical ventilation with PEEP in patients with cardiogenic shock.

    Science.gov (United States)

    Wiesen, Jonathan; Ornstein, Moshe; Tonelli, Adriano R; Menon, Venu; Ashton, Rendell W

    2013-12-01

    The need to provide invasive mechanical ventilatory support to patients with myocardial infarction and acute left heart failure is common. Despite the large number of patients requiring mechanical ventilation in this setting, there are remarkably few data addressing the ideal mode of respiratory support in such patients. Although there is near universal acceptance regarding the use of non-invasive positive pressure ventilation in patients with acute pulmonary oedema, there is more concern with invasive positive pressure ventilation owing to its more significant haemodynamic impact. Positive end-expiratory pressure (PEEP) is almost universally applied in mechanically ventilated patients due to benefits in gas exchange, recruitment of alveolar units, counterbalance of hydrostatic forces leading to pulmonary oedema and maintenance of airway patency. The limited available clinical data suggest that a moderate level of PEEP is safe to use in severe left ventricular (LV) dysfunction and cardiogenic shock, and may provide haemodynamic benefits as well in LV failure which exhibits afterload-sensitive physiology.

  19. Bussijuhtide kindrali rasked päevad / Peep Peterson ; interv. Tanel Raig

    Index Scriptorium Estoniae

    Peterson, Peep, 1975-

    2007-01-01

    Eesti Transpordi- ja Teetöötajate Ametiühingu esimees Peep Peterson vastab bussijuhtide ja tööandjate vahelisi lahkhelisid, ametiühinguliikumist ning kokkuleppe sõlmimist puudutavatele küsimustele. Kommenteerivad: Villem Tori. Streikija iseloomuga raske vastane; Henn Pärn. Peterson saavutas maksimumide maksimumi; Harri Taliga. Ametiühingu liidritel erinevad arusaamad. Lisa: Fakte eluloost

  20. A large-angle cold-neutron bender using sequential garland reflections

    CERN Document Server

    Suzuki, J; Tasaki, S; Ebisawa, T

    2002-01-01

    We discuss the principle and performance of a new cold-neutron bender using sequential garland reflections in order to bend a neutron beam with a large divergence to a large angle. Using this bender for a pulsed neutron source, we can distribute cold neutrons or polarized cold neutrons if necessary to plural spectrometers at a cold-neutron-guide tube to avoid the frame-overlap problem of cold neutrons. (orig.)

  1. A PROCEDURE TO CALIBRATE AND PERFORM THE BENDER ELEMENT TEST

    Directory of Open Access Journals (Sweden)

    JAVIER FERNANDO CAMACHO-TAUTA

    2012-01-01

    Full Text Available El método de ensayo bender element es utilizado en laboratorio para obtener la velocidad de la onda cortante de suelos. A pesar de su aparente simplicidad, aún no existe una norma para este ensayo. Existen factores que pueden tener alguna incidencia sobre el resultado. Estos factores son tenidos en cuenta para diseñar y construir un sistema de ensayo en una cámara triaxial. Se propone un método para calibrar el sistema mediante la utilización de barras de aluminio de diferente longitud y se hacen recomendaciones para la ejecución del ensayo, en lo relacionado con la selección de la frecuencia del pulso sinusoidal utilizado para producir la perturbación. Finalmente, se presentan ensayos efectuados sobre dos muestras de arena.

  2. Reliability of Single-Use PEEP-Valves Attached to Self-Inflating Bags during Manual Ventilation of Neonates – An In Vitro Study

    Science.gov (United States)

    Hartung, Julia C.; Wilitzki, Silke; Thio-Lluch, Marta; te Pas, Arjan B.; Schmalisch, Gerd; Roehr, Charles C.

    2016-01-01

    Introduction International resuscitation guidelines suggest to use positive end-expiratory pressure (PEEP) during manual ventilation of neonates. Aim of our study was to test the reliability of self-inflating bags (SIB) with single-use PEEP valves regarding PEEP delivery and the effect of different peak inflation pressures (PIP) and ventilation rates (VR) on the delivered PEEP. Methods Ten new single-use PEEP valves from 5 manufacturers were tested by ventilating an intubated 1kg neonatal manikin containing a lung model with a SIB that was actuated by an electromechanical plunger device. Standard settings: PIP 20cmH2O, VR 60/min, flow 8L/min. PEEP settings of 5 and 10cmH2O were studied. A second test was conducted with settings of PIP 40cmH2O and VR 40/min. The delivered PEEP was measured by a respiratory function monitor (CO2SMO+). Results Valves from one manufacturer delivered no relevant PEEP and were excluded. The remaining valves showed a continuous decay of the delivered pressure during expiration. The median (25th and 75th percentile) delivered PEEP with standard settings was 3.4(2.7–3.8)cmH2O when set to 5cmH2O and 6.1(4.9–7.1)cmH2O when set to 10cmH2O. Increasing the PIP from 20 to 40 cmH2O led to a median (25th and 75th percentile) decrease in PEEP to 2.3(1.8–2.7)cmH2O and 4.3(3.2–4.8)cmH2O; changing VR from 60 to 40/min led to a PEEP decrease to 2.8(2.1–3.3)cmH2O and 5.0(3.5–6.2)cmH2O for both PEEP settings. Conclusion Single-use PEEP valves do not reliably deliver the set PEEP. PIP and VR have an effect on the delivered PEEP. Operators should be aware of these limitations when manually ventilating neonates. PMID:26914209

  3. Reliability of Single-Use PEEP-Valves Attached to Self-Inflating Bags during Manual Ventilation of Neonates--An In Vitro Study.

    Directory of Open Access Journals (Sweden)

    Julia C Hartung

    Full Text Available International resuscitation guidelines suggest to use positive end-expiratory pressure (PEEP during manual ventilation of neonates. Aim of our study was to test the reliability of self-inflating bags (SIB with single-use PEEP valves regarding PEEP delivery and the effect of different peak inflation pressures (PIP and ventilation rates (VR on the delivered PEEP.Ten new single-use PEEP valves from 5 manufacturers were tested by ventilating an intubated 1 kg neonatal manikin containing a lung model with a SIB that was actuated by an electromechanical plunger device. Standard settings: PIP 20 cmH2O, VR 60/min, flow 8 L/min. PEEP settings of 5 and 10 cmH2O were studied. A second test was conducted with settings of PIP 40 cmH2O and VR 40/min. The delivered PEEP was measured by a respiratory function monitor (CO2SMO+.Valves from one manufacturer delivered no relevant PEEP and were excluded. The remaining valves showed a continuous decay of the delivered pressure during expiration. The median (25th and 75th percentile delivered PEEP with standard settings was 3.4(2.7-3.8 cmH2O when set to 5 cmH2O and 6.1(4.9-7.1 cmH2O when set to 10 cmH2O. Increasing the PIP from 20 to 40 cmH2O led to a median (25th and 75th percentile decrease in PEEP to 2.3(1.8-2.7 cmH2O and 4.3(3.2-4.8 cmH2O; changing VR from 60 to 40/min led to a PEEP decrease to 2.8(2.1-3.3 cmH2O and 5.0(3.5-6.2 cmH2O for both PEEP settings.Single-use PEEP valves do not reliably deliver the set PEEP. PIP and VR have an effect on the delivered PEEP. Operators should be aware of these limitations when manually ventilating neonates.

  4. Reliability of Single-Use PEEP-Valves Attached to Self-Inflating Bags during Manual Ventilation of Neonates--An In Vitro Study.

    Science.gov (United States)

    Hartung, Julia C; Wilitzki, Silke; Thio-Lluch, Marta; te Pas, Arjan B; Schmalisch, Gerd; Roehr, Charles C

    2016-01-01

    International resuscitation guidelines suggest to use positive end-expiratory pressure (PEEP) during manual ventilation of neonates. Aim of our study was to test the reliability of self-inflating bags (SIB) with single-use PEEP valves regarding PEEP delivery and the effect of different peak inflation pressures (PIP) and ventilation rates (VR) on the delivered PEEP. Ten new single-use PEEP valves from 5 manufacturers were tested by ventilating an intubated 1 kg neonatal manikin containing a lung model with a SIB that was actuated by an electromechanical plunger device. Standard settings: PIP 20 cmH2O, VR 60/min, flow 8 L/min. PEEP settings of 5 and 10 cmH2O were studied. A second test was conducted with settings of PIP 40 cmH2O and VR 40/min. The delivered PEEP was measured by a respiratory function monitor (CO2SMO+). Valves from one manufacturer delivered no relevant PEEP and were excluded. The remaining valves showed a continuous decay of the delivered pressure during expiration. The median (25th and 75th percentile) delivered PEEP with standard settings was 3.4(2.7-3.8) cmH2O when set to 5 cmH2O and 6.1(4.9-7.1) cmH2O when set to 10 cmH2O. Increasing the PIP from 20 to 40 cmH2O led to a median (25th and 75th percentile) decrease in PEEP to 2.3(1.8-2.7) cmH2O and 4.3(3.2-4.8) cmH2O; changing VR from 60 to 40/min led to a PEEP decrease to 2.8(2.1-3.3) cmH2O and 5.0(3.5-6.2) cmH2O for both PEEP settings. Single-use PEEP valves do not reliably deliver the set PEEP. PIP and VR have an effect on the delivered PEEP. Operators should be aware of these limitations when manually ventilating neonates.

  5. Correlation of the Scores on Barron's Ego Strength Scale with the Scores on the Bender-Gestalt Test.

    Science.gov (United States)

    Martin, John D.; And Others

    1979-01-01

    The degree of relationship between scores on the Barron Ego Strength Scale and the scores on the Bender-Gestalt Test was investigated on a sample of college students. Correlations were moderate to low. Racial differences were observed on the Bender-Gestalt Test. (Author/JKS)

  6. Comparison of the Qualitative and Developmental Scoring Systems for the Modified Version of the Bender-Gestalt Test.

    Science.gov (United States)

    Brannigan, Gary G.; Brunner, Nancy A.

    1993-01-01

    Examined two scoring systems for Modified Version of the Bender-Gestalt Test. Administered Bender-Gestalt and Otis-Lennon School Ability Test to 75 first-grade and 84 second-grade students. Both systems were significantly correlated with school ability. Results of tests for differences between correlations indicated that Qualitative Scoring System…

  7. The Performance of Learning Disabled Children on the Kaufman Assessment Battery for Children and the Bender-Gestalt Test.

    Science.gov (United States)

    Haddad, Frederick A.

    1986-01-01

    Results of the Kaufman Assessment Battery for Children (K-ABC) and Bender-Gestalt Test were compared for a sample of learning disabled children that included 24 blacks and 24 whites; mean age 9 years. A significant correlation coefficient was found between the K-ABC Simultaneous Scale and the Bender-Gestalt Test error score. Implications of these…

  8. Comparison of the Bender Gestalt Test for Both Black and White Brain-Damaged Patients Using Two Scoring Systems

    Science.gov (United States)

    Butler, Oliver T.; And Others

    1976-01-01

    This study tested for cultural bias in the Bender Visual Motor Gestalt Test. Subjects were 72 black and white patients diagnosed as either brain damaged or psychiatric. Bender protocols were scored by Pascal-Suttell and Hain systems. No race effect appeared except for the Pascal-Suttell system for which blacks scored significantly better. (Author)

  9. Bender test (B-SPG and HFD-escala Sisto: Validity by contrasting groups

    Directory of Open Access Journals (Sweden)

    Daniel Bartholomeu

    2013-02-01

    Full Text Available This study investigated validity evidences by contrasting groups for the Bender (B-SPG and DFH-Escala Sisto. The instruments were administered to 244 pupils, being 50.4% boys and all of them aged from seven to 10 years, with an average of eight years (DP=1,08 attending from first to fourth grades of the basic education of a public school in the state of São Paulo. The tests were collectively administered and the slides of the Bender test were projected in the blackboard to be copied by the children. Differences between the extreme groups of the DFH in relation to the Bender scores were evidenced in all the studied situations. It was concluded that the Gestaltic Test furnishes an estimative of the intellectual capacities of children and differentiates those with bigger scores in the DFH from those less scored.

  10. Comparison of the Bender-Gestalt and revised Developmental Test of Visual-Motor Integration.

    Science.gov (United States)

    Armstrong, B B; Knopf, K F

    1982-08-01

    The Bender-Gestalt and the Developmental Test of Visual-motor Integration were administered to two groups of 40 children each, ages 7 through 10 yr. Developmental age scores (Koppitz scoring) and age equivalents (Revised Beery manual) were obtained. Children screened for learning disabilities were selected for one group and children enrolled in regular classrooms were selected for another group. The correlation of .74 between the Bender and Beery test scores was high and statistically significant for the learning-disabled group. The correlation of .36 was low though statistically significant for the regular students, which suggests the groups performed differently on the tests. A significant mean difference of 9 mo. was noted between the Bender and Beery scores.

  11. Bender performance and socioeconomic status in Mexican children: a cross-cultural study.

    Science.gov (United States)

    Fernández, T; Tuset, A M

    2007-12-01

    Normative data are presented for Bender test performance, following the system of Koppitz, of 695 Mexican students between 5.0 and 12.1 yr. old (M = 8.7, SD = 2.01) and belonging to different socioeconomic status. The data are compared with the normative group of U.S. students used by Koppitz and with a representative sample of children from Barcelona, Spain. The results indicate that the total number of Bender errors decreased with increasing age of the children and that significant differences existed with respect to socioeconomic status. The comparison of these data with U.S. and Spanish children shows significant differences in all age groups, with the Mexican children scoring lowest. Differences in quality of schooling and in other aspects of education could explain the variability in Bender test performance.

  12. The Bender-Gestalt with adolescents: comparison of two scoring systems.

    Science.gov (United States)

    McIntosh, J A; Belter, R W; Saylor, C F; Finch, A J; Edwards, G L

    1988-03-01

    The present study was designed to evaluate the relative efficacy of two different scoring systems (Koppitz, 1975; Lacks, 1984) for use in evaluating Bender-Gestalt performance by adolescents. Normative data are presented for the two scoring systems with a sample of "normal" controls (N = 150), emotionally disturbed (N = 140), and mentally retarded/neurologically impaired adolescents (N = 47), aged 12-17. Results suggested that age and psychopathology were not related to the quality of the Bender-Gestalt reproductions of these subjects. An inverse relationship was found between cognitive ability and visual motor skills. Data obtained from these samples of adolescents showed a high degree of consistency between the scoring systems, which suggests that either scoring procedure is suitable for evaluating the Bender-Gestalt performance of adolescents.

  13. Turkish children's Bender-Gestalt test performance: differences in public and private school children.

    Science.gov (United States)

    Ozer, Serap

    2011-02-01

    The present study was undertaken to provide data on the Bender-Gestalt test for children aged 5 to 11 in Turkey. Although it is well documented that sociocultural factors are important in cognitive evaluations, the effects of type of school and differing educational opportunities provided by these schools on the Bender-Gestalt test have not been previously investigated. The aim of the present study was to investigate the effect of age, sex, and school type on Bender-Gestalt performance. The test was individually administered to 484 children between the ages of 5 and 11 years. The children were enrolled in either public or private schools. Koppitz's Developmental Scoring System was utilized. The results indicated that older children performed with fewer errors. Girls performed with fewer errors than boys. Finally, as expected, private school children outperformed their public school peers. The results are discussed with respect to the importance of taking into account various educational factors in utilizing commonly used tests.

  14. A solution approach to the ROADEF/EURO 2010 challenge based on Benders' Decomposition

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Muller, Laurent Flindt; Petersen, Bjørn

    We present a Benders’ decomposition based framework for solving a large scale energy management problem with varied constraints posed as the ROADEF/EURO 2010 challenge. Because of the nature of the problem, not all constraints can be modeled satisfactorily as linear constraints and the approach...... is therefore divided into two stages: in the first stage Benders feasibility and optimality cuts are added based on the linear programming relaxation of the Benders Master problem, and in the second stage feasible integer solutions are enumerated and procedure is applied to each solution in an attempt to make...

  15. Bender scores and the horse as a distinct item on object assembly of the WISC.

    Science.gov (United States)

    Thomas, A D

    1984-08-01

    This exploratory study investigated the relationship between two measures of perceptual-motor problems. Ratios derived from the Object Assembly subtest of the WISC with errors greater than 1 SD on the Bender test using Koppitz' scoring system were compared. The sample of 66 white middle-class children was 6 to 11 yr. old. The particular ratio studied was statistically significantly associated with the Bender, whereas ratios of other Object Assembly items were not. The Horse ratio was also significantly associated with the presence of learning problems shown in children's files.

  16. Realisation of a novel crystal bender for a fast double crystal monochromator

    Energy Technology Data Exchange (ETDEWEB)

    Zaeper, R.; Richwin, M. E-mail: richwin@uni-wuppertal.de; Wollmann, R.; Luetzenkirchen-Hecht, D.; Frahm, R

    2001-07-21

    A novel crystal bender for an X-ray undulator beamline as part of a fast double crystal monochromator development for full EXAFS energy range was characterized. Rocking curves of the monochromator crystal system were recorded under different heat loads and bending forces of the indirectly cooled first Si(1 1 1) crystal. The monochromator development implements new piezo-driven tilt tables with wide angular range to adjust the crystals' Bragg angles and a high pressure actuated bender mechanism for the first crystal.

  17. Realisation of a novel crystal bender for a fast double crystal monochromator

    CERN Document Server

    Zaeper, R; Wollmann, R; Luetzenkirchen-Hecht, D; Frahm, R

    2001-01-01

    A novel crystal bender for an X-ray undulator beamline as part of a fast double crystal monochromator development for full EXAFS energy range was characterized. Rocking curves of the monochromator crystal system were recorded under different heat loads and bending forces of the indirectly cooled first Si(1 1 1) crystal. The monochromator development implements new piezo-driven tilt tables with wide angular range to adjust the crystals' Bragg angles and a high pressure actuated bender mechanism for the first crystal.

  18. UT küsib / Gutaker, Piotr; Sütt, Piret; Asser, Toomas; Käiss, Peep; Varblane, Anu

    Index Scriptorium Estoniae

    2006-01-01

    Universitas Tartuensise küsimustele 2006. aasta tööde ja tegemiste kohta vastavad välissuhete osakonna praktikant Piotr Gutaker, akadeemilise naiskoori liige Piret Sütt, arstiteaduskonna dekaan Toomas Asser, TÜ üliõpilasesinduse esimees Peep Käiss ja majandusteaduskonna üliõpilane Anu Varblane

  19. UT küsib / Gutaker, Piotr; Sütt, Piret; Asser, Toomas; Käiss, Peep; Varblane, Anu

    Index Scriptorium Estoniae

    2006-01-01

    Universitas Tartuensise küsimustele 2006. aasta tööde ja tegemiste kohta vastavad välissuhete osakonna praktikant Piotr Gutaker, akadeemilise naiskoori liige Piret Sütt, arstiteaduskonna dekaan Toomas Asser, TÜ üliõpilasesinduse esimees Peep Käiss ja majandusteaduskonna üliõpilane Anu Varblane

  20. Review: artifical ventilation with positive end-expiratory pressure (PEEP). Historical background, terminology and patho-physiology.

    Science.gov (United States)

    Stokke, D B

    1976-09-01

    CPPV (continuous positive pressure ventilation) is obviously superior to IPPV (intermittent positive pressure ventilation) for the treatment of patients with acute respiratory insufficiency (ARI) and results within a few minutes in a considerable increase in the oxygen transport. The principle is to add a positive end-expiratory plateau (PEEP) to IPPV, with a subsequent increase in FRC (functional residual capacity) resulting in re-opening in first and foremost the declive alveolae, which can then once again take part in the gas exchange and possibly re-commence the disrupted surfactant production. In this manner the ventilation/perfusion ratio in the diseases lungs is normalized and the intrapulmonary shunting of venous blood (Qs/Qt) will decrease. At the same time the dead space ventilation fraction (VD/VT) normalizes and the compliance of the lungs (CL) increases. The PEEP value, which results in a maximum oxygen transport, and the lowest dead space fraction, also appears to result in the greatest total static compliance (CT) and the greatest increase in mixed venous oxygen tension (PVO2); this value can be termed "optimal PEEP". The greater the FRC is, with an airway pressure = atmospheric pressure, the lower the PEEP value required in order to obtain maximum oxygen transport. If the optimal PEEP value is exceeded the oxygen transport will fall because of a falling Qt (cardiac output) due to a reduction in venous return. CT and PVO2 will fall and VD/VT will increase. Increasing hyperinflation of the alveolae will result in a rising danger of alveolar rupture. The critical use of CPPV treatment means that the lungs may be safeguarded against high oxygen percents. The mortality of newborn infants with RDS (respiratory distress syndrome) has fallen considerably after the general introduction of CPPV and CPAP (continuous positive airway pressures). The same appears to be the case with adults suffering from ARI (acute respiratory insufficiency).

  1. Positive end-expiratory pressure (PEEP) does not depress left ventricular function in patients with pulmonary edema

    Energy Technology Data Exchange (ETDEWEB)

    Calvin, J.E.; Driedger, A.A.; Sibbald, W.J.

    1981-08-01

    Researchers evaluated the effects of positive end-expiratory pressure (PEEP) on left ventricular function in 15 patients with acute respiratory insufficiency secondary to pulmonary edema with invasive (pressure; flow) measurements and radionuclide angiography (RA). Using RNA allowed a definition of the left ventricular ejection fraction (LVEF), and then calculation of the left ventricular end-diastolic volume (LVEDV), both before and after PEEP. With a mean PEEP of 14.2 +/- 1.8 cm H2O (mean +/- SD) (range, 10 to 15), a fall in the cardiac index (4.34 +/- 1.5 to 3.84 +/- 1.4 L/min/M2; p less than 0.001) was accompanied by a significant decrease in the stroke volume index (42 +/- 13 to 39 +/- 12 ml/beat M2; p less than 0.01) and pulse rate (103.4 +/- 14.3 to 98 +/- 13.5 beats/min; p less than 0.01). The decrease in the stroke volume index was primarily due to a significant decrease in left ventricular preload (LVEDV) from 85.9 +/- 19 to 71.4 +/- 21.4 ml/m2 (p less than 0.01). Simultaneously, the mean LVEF increased from 0.47 +/- 0.10 to 0.53 +/- 0.08 (p less than 0.05), despite a significant increase in the systemic vascular resistance (1,619 +/- 575 to 1,864 +/- 617 dynes . s. cm-5/M2; p less than 0.01). Researchers concluded that the use of PEEP in patients with acute pulmonary edema, to the degree used in this study, may depress cardiac output by simply decreasing left ventricular preload. Researchers were unable to produce any evidence that would support a change in the contractile state of the left ventricle as a cause of depressed forward flow with the use of PEEP.

  2. Bender-Gestalt Test and Social Interactions of Kindergarten Children: Effects of Socialization Practices

    Science.gov (United States)

    Lifshitz, Michaela

    1978-01-01

    The present study assessed the extent to which kindergarten children's performance on the Bender-Gestalt Test is related to sex and sociocultural variables and to children's social behavior. Two distinctly different Israeli populations were included: the Druze and the Jews. Significant correlations between perceptual indicators and social…

  3. The Bender Visual Motor Gestalt Test: Implications for the Diagnosis and Prediction of Reading Achievement.

    Science.gov (United States)

    Lesiak, Judi

    1984-01-01

    Reviews 32 studies about the utility of the Bender Visual-Motor Gestalt Test (BG) as a predictor of reading, its relationship to reading achievement, and ability to differentiate between good and poor readers. Results question the use of the BG (scored using discrete error systems) in a diagnostic reading battery. (BH)

  4. Comparison of Two Scoring Systems for the Modified Version of the Bender-Gestalt Test.

    Science.gov (United States)

    Schachter, Steven; And Others

    1991-01-01

    Examined relative utility of two scoring systems for Modified Version of Bender-Gestalt Test in predicting performance on Developmental Test of Visual-Motor Integration. Findings from 53 kindergarten and 47 first grade students indicated that Qualitative Scoring System was significantly better predictor of visual-motor integration skills than…

  5. Comparison of the Bender-Gestalt and Revised Developmental Test of Visual-Motor Integration.

    Science.gov (United States)

    Armstrong, Barbara B.; Knopf, Karen F.

    1982-01-01

    Using children with learning disabilities and children enrolled in regular classrooms, test scores on the Bender-Gestalt and the Developmental Test of Visual-Motor Integration indicated high and significant correlations for the learning-disabled group and low but significant correlations for regular students. A nine-month mean difference in scores…

  6. Bender Gestalt Test Performance and the Word Recognition Skills of Disadvantaged Children

    Science.gov (United States)

    Baker, E. H.; Thurber, Steven

    1976-01-01

    The Bender Gestalt Test and the WRAT reading section were administered to 147 disadvantaged children. The zero-order correlation of -.62 was found to be moderated by the variable of age. For younger subjects, highly significant first- and second-order partial correlations were obtained with age and/or WISC information scores held constant. (Author)

  7. Further Validation of the Qualitative Scoring System for the Modified Bender-Gestalt Test.

    Science.gov (United States)

    Brannigan, Gary G.; And Others

    1995-01-01

    Compares the Qualitative Scoring System and the Developmental Scoring Systems, both Bender-Gestalt tests, in predicting achievement on the Metropolitan Achievement Test (MAT). In this study, first through fourth graders (n=409) from regular elementary schools were subjected to both tests; both systems correlated significantly with school…

  8. Comparison of the Koppitz and Watkins Scoring Systems for the Bender Gestalt Test.

    Science.gov (United States)

    Johnston, Cris W.; Lanak, Brenda

    1985-01-01

    The Bender Gestalt Test was administered to 25 children (7-10 years old) referred for neuropsychological assessment and scored using the Koppitz system and the Watkins system. Although the scores obtained using the two different sets of criteria were highly correlated, the Watkins rules produced generally better performance. (Author/CL)

  9. Concurrent validity of the Koppitz Bender-Gestalt emotional indicators among women with mental retardation.

    Science.gov (United States)

    Dixon, J L

    1998-02-01

    This study evaluated the concurrent validity of Koppitz' revised Bender-Gestalt Emotional Indicators among 44 women with mental retardation. The concurrent validity of the Emotional Indicator total score was not supported when compared with responses on two widely used and accepted screening inventories, the Reiss Screen and the Inventory for Client and Agency Planning.

  10. Koppitz errors on the Bender-Gestalt for adult retardates: normative data.

    Science.gov (United States)

    Andert, J N; Dinning, W D; Hustak, T L

    1976-04-01

    Normative data on the Koppitz developmental scoring system for the Bender-Gestalt test were derived from a sample which included 510 protocols of adult resident retardates. Percentile norms are presented on Koppitz error scores for three AAMD ranges of retardation based on WAIS IQs and two AAMD ranges of retardation based on Stanford-Binet IQs.

  11. Assessing Secondary Students with the Bender, VADS, and HFD: Research and Application.

    Science.gov (United States)

    Koppitz, Elizabeth M.

    The Koppitz Minibattery, that is, the Bender Gestalt Test, the Visual Aural Digit Span Test (VADS), and the Human Figure Drawing (HFD), was adopted and extended for use with middle school pupils (aged 11 to 14). Similarities and differences for older and younger children are described in behavior observation, objective scores and the qualitative…

  12. A Comparison of Special Education Teacher and Psychologist Scoring of the Bender Visual Motor Gestalt Test

    Science.gov (United States)

    Foster, Glen G.; And Others

    1976-01-01

    Ten special education teachers and two school psychologists scored the Bender-Gestalt protocals of elementary school children using the Koppitz scoring system. The reported correlations between teachers and school psychologists compared favorably to correlations between school psychologists as well as to interrater reliabilities reported in the…

  13. Performance of American Indian Children Compared with Koppitz Normative Population on the Bender.

    Science.gov (United States)

    Lansford, L. M.; Asmussen, J. M.

    Differences in the normative data presented in the Koppitz Scoring System for the Bender Gestalt Test (a measure for diagnosing learning and neurological disorders) were compared for 838 elementary age children of the Sioux, Chippewa, Navajo, and Apache tribes and a Koppitz normative group. Considered were mean error differences and mean time…

  14. Emotional Indicators on the Bender-Gestalt and the Devereux Child Behavior Rating Scale

    Science.gov (United States)

    Gregory Mary K.

    1977-01-01

    A heterogeneous group of elementary school children referred for psycho-educational diagnosis were rated on the Devereux Child Behavior Rating Scale and the Bender Visual-Motor Gestalt Test, scoring for Koppitz Emotional Indicators. Findings suggests that certain DCB factors may be more predictive of emotional problems than others in the scale.…

  15. Koppitz scoring system as a measure of Bender-Gestalt performance in behaviorally and emotionally disturbed adolescents.

    Science.gov (United States)

    Shapiro, S K; Simpson, R G

    1995-01-01

    Data are presented to assess the use of the Koppitz scoring system for the Bender-Gestalt Test in a sample (N = 87) of behaviorally and emotionally disturbed adolescents. Results suggested that age was modestly related to Koppitz Developmental scores, an indication that visual-motor skills continue to develop beyond age 11. Scores were related to spatial perception skills as measured on the WISC-R. Gender, primary psychiatric diagnosis, educational tests, and MMPI scores were not related to Bender performance. Findings are discussed in terms of a need for additional research into the utility of the Bender as a measure of visual-motor skills in adolescents.

  16. A benders decomposition approach to multiarea stochastic distributed utility planning

    Science.gov (United States)

    McCusker, Susan Ann

    Until recently, small, modular generation and storage options---distributed resources (DRs)---have been installed principally in areas too remote for economic power grid connection and sensitive applications requiring backup capacity. Recent regulatory changes and DR advances, however, have lead utilities to reconsider the role of DRs. To a utility facing distribution capacity bottlenecks or uncertain load growth, DRs can be particularly valuable since they can be dispersed throughout the system and constructed relatively quickly. DR value is determined by comparing its costs to avoided central generation expenses (i.e., marginal costs) and distribution investments. This requires a comprehensive central and local planning and production model, since central system marginal costs result from system interactions over space and time. This dissertation develops and applies an iterative generalized Benders decomposition approach to coordinate models for optimal DR evaluation. Three coordinated models exchange investment, net power demand, and avoided cost information to minimize overall expansion costs. Local investment and production decisions are made by a local mixed integer linear program. Central system investment decisions are made by a LP, and production costs are estimated by a stochastic multi-area production costing model with Kirchhoff's Voltage and Current Law constraints. The nested decomposition is a new and unique method for distributed utility planning that partitions the variables twice to separate local and central investment and production variables, and provides upper and lower bounds on expected expansion costs. Kirchhoff's Voltage Law imposes nonlinear, nonconvex constraints that preclude use of LP if transmission capacity is available in a looped transmission system. This dissertation develops KVL constraint approximations that permit the nested decomposition to consider new transmission resources, while maintaining linearity in the three

  17. Between preservation and transformation. First considerations about the recovery of the peep districts in Parma

    Directory of Open Access Journals (Sweden)

    Luca Gullì

    2012-10-01

    Full Text Available The regeneration policy of the PEEP districts, can contribute to the enrichment of the theoretical framework formulated for the protection of the heritage of the Modern Movement. In 2011, the Municipality of Parma, showing a new awareness in relation to assets until now rarely considered, devices a specific field of study within its structural urbanistic plan. In the absence of a regulatory framework of reference, it is crucial to build up the appropriate frameworks of knowledge directed to operational decisions. This can be done by specifically dedicated archives to which to entrust with the definition of a body of rules of urban planning and housing tailored to the particularities of these settlements and to the real questions of transformation that can arise in them.

  18. Koppitz Bender Gestalt Scores in First-Grade Children as Related to Ethnocultural Background, Socioeconomic Class, and Sex Factors

    Science.gov (United States)

    Zuelzer, Margot B.; And Others

    1976-01-01

    This study investigated whether Koppitz Bender Gestalt Scores were related to ethnocultural, socioeconomic and sex factors when statistical controls for intelligence were used. When intelligence was controlled for, it eliminated many effects for these variables. Results are discussed. (NG)

  19. Test gestaltico visomotor de bender modificado y test de caras: una evaluacion de la validez de constructo

    National Research Council Canada - National Science Library

    Merino Soto, Cesar

    2011-01-01

    La investigacion con las nuevas versiones del Test Gestaltico de Bender (TGB) apenas ha llamado la atencion en el mundo hispano, considerando que esta prueba es una de las mas utilizadas en la evaluacion psicologica...

  20. A comparison of clinical and nonclinical groups of children on the bender - gestalt and draw a person tests

    OpenAIRE

    Özer, Serap

    2010-01-01

    The present study compared a clinical and a control sample of Turkish children on the Bender Gestalt and Draw A Person tests. 44 of the children from a clinic sample were compared to 44 children from a matched nonclinical school sample The tests were scored according to the Koppitz criteria. ANOVA comparisons showed differences on the Bender Gestalt test, and the HFD. The two groups did not differ on the number of Emotional Indicators. Correct classification of the children in the clinical gr...

  1. 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

  2. Riding with the ants

    NARCIS (Netherlands)

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

    2017-01-01

    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 Xenope

  3. 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.

    2016-01-01

    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 Xenope

  4. Differential Effects of Intraoperative Positive End-expiratory Pressure (PEEP) on Respiratory Outcome in Major Abdominal Surgery Versus Craniotomy

    DEFF Research Database (Denmark)

    de Jong, Myrthe A C; Ladha, Karim S; Melo, Marcos F Vidal

    2015-01-01

    OBJECTIVES: In this study, we examined whether (1) positive end-expiratory pressure (PEEP) has a protective effect on the risk of major postoperative respiratory complications in a cohort of patients undergoing major abdominal surgeries and craniotomies, and (2) the effect of PEEP is differed...... abdominal surgery patients and 5063 craniotomy patients. Analysis was performed using multivariable logistic regression. The primary outcome was a composite of major postoperative respiratory complications (respiratory failure, reintubation, pulmonary edema, and pneumonia) within 3 days of surgery. RESULTS...... odds of respiratory complications in patients undergoing major abdominal surgery (odds ratio 0.53, 95% confidence interval 0.39 - 0.72), effects that translated to deceased hospital length of stay [median hospital length of stay : 6 days (4-9 days), incidence rate ratios for each additional day: 0...

  5. Turkish children's Bender-Gestalt Test performance: a pilot study and preliminary norms.

    Science.gov (United States)

    Ozer, Serap

    2007-12-01

    The present study was undertaken to provide preliminary data for norms on the Bender-Gestalt Test for 253 children ages 5 yr., 5 mo. to 11 yr., 10 mo. in Turkey. The Koppitz Developmental Scoring System gave mean error scores of 4.2 (SD = 3.3) for girls and 3.6 (SD = 3.0) for boys. The mean error scores obtained by all age groups are presented and compared with other cross-cultural data. These scores decreased across age groups, supporting Bender's maturational hypothesis of the test. The present sample performed at a higher developmental level than the Koppitz normative sample for the 5- and 6-year age groups, while means for other age groups were similar to the original U.S. norms. That this pattern is supported in other cross-cultural studies is discussed as well as the importance of developing local norms for visual spatial tests.

  6. Evidências de validade para o teste gestáltico visomotor de Bender

    OpenAIRE

    Silva, Roselaine Berenice Ferreira da

    2008-01-01

    Esta tese trata da qualidade de instrumentos psicológicos, dando destaque ao Teste Gestáltico Visomotor de Bender. O trabalho está constituído por três estudos, dentre os quais um em específico se propõe a resgatar a história do instrumento, desde sua construção, com os estudos iniciais de Lauretta Bender (1938), até a consolidação de diversos sistemas de correção. Para este propósito foi feito levantamento bibliográfico em bancos de dados PsychInfo, Bireme, BVS (Biblioteca Virtual de Saúde) ...

  7. Characterization of an X-ray mirror mechanical bender for the European XFEL.

    Science.gov (United States)

    Vannoni, Maurizio; Freijo Martín, Idoia; Sinn, Harald

    2016-07-01

    One of the classical devices used to tune a mirror on an X-ray optical setup is a mechanical bender. This is often designed in such a way that the mirror is held with clamps on both ends; a motor is then used to put a torque on the clamps, inducing a cylindrical shape of the mirror surface. A mechanical bender with this design was recently characterized, to bend a 950 mm-long mirror up to a radius of curvature of 10 km. The characterization was performed using a large-aperture Fizeau interferometer with an angled incidence setup. Some particular and critical effects were investigated, such as calibration, hysteresis, twisting and long-term stability.

  8. Benders' Decomposition Based Heuristics for Large-Scale Dynamic Quadratic Assignment Problems

    Directory of Open Access Journals (Sweden)

    Sirirat Muenvanichakul

    2009-01-01

    Full Text Available Problem statement: Dynamic Quadratic Assignment Problem (DQAP is NP hard problem. Benders decomposition based heuristics method is applied to the equivalent mixed-integer linear programming problem of the original DQAP. Approach: Approximate Benders Decomposition (ABD generates the ensemble of a subset of feasible layout for Approximate Dynamic Programming (ADP to determine the sub-optimal optimal solution. A Trust-Region Constraint (TRC for the master problem in ABD and a Successive Adaptation Procedure (SAP were implemented to accelerate the convergence rate of the method. Results: The sub-optimal solutions of large-scales DQAPs from the method and its variants were compared well with other metaheuristic methods. Conclusion: Overall performance of the method is comparable to other metaheuristic methods for large-scale DQAPs.

  9. Measuring Growth and Decline in Visual-Motor Processes with the Bender-Gestalt Second Edition

    Science.gov (United States)

    Decker, Scott L.

    2008-01-01

    The purpose of this study is to develop a change-sensitive scale for evaluating developmental change in visual-motor ability across the life span. A partial-credit item-response model is used to estimate theta values for each age group between 4 and 90 using the Bender-Gestalt II standardization sample (N = 4,000). Results from this study suggest…

  10. THE INCIDENCE OF BENDER-GESTALT FIGURE DEVIATIONS IN A GROUP OF MENTALLY RETARDED PSYCHIATRIC PATIENTS

    Directory of Open Access Journals (Sweden)

    Habibollah Ghassemzadeh

    1994-06-01

    Full Text Available The Bender-Gestalt Test was given to thirty mentally-retarded psychiatric patients. The mean, standard deviation, and standard error were 56.73, 26.25, and 4.80 respectively. Rotation was the most frequent major deviation which occurred in all the designs."nDesign # 7 was the most difficult one to be reproduced in the sample. This design by itself, was subject to 47% of distortion, 79% of omission, and 21% of rotation.

  11. Characterization of a mechanical bender for x-ray mirrors at European XFEL

    Science.gov (United States)

    Freijo Martín, Idoia; Vannoni, Maurizio; Music, Valerija; Sinn, Harald

    2016-09-01

    The European XFEL will generate extremely short and intense X-ray laser pulses of high coherence and nearly diffraction-limited divergence. Guiding these X-rays beams over a distance of more than 1 km to the experiments requires an extreme precision in pointing stability of beamline components like mirrors and gratings and also a control of the divergence of the beam. The specifications of the X-ray mirrors that will be able to transport, distribute and focus the beam are quite challenging. The European XFEL mirrors for the beam transport are 950 mm long and the optical surface specifications are 2 nm Peak-To-Valley. Some of the mirrors will have bending capabilities in order to focus the beam in the right position and with nanometer accuracy. This is implemented using a mechanical bender that will ensure stability of the optics in the nanometer range and will also offer the possibility to correct for mechanical or temperature drifts. We present here the characterization of a mechanical bender that was done using two instruments, a Large Aperture Fizeau interferometer and a system of three capacitive sensors. The bender is designed in a way that the mirror is hold with clamps on both ends and a symmetric torque is applied on the clamps, inducing a cylindrical shape on the mirror surface. Several long-term stability measurements were done, as well as the characterization of bending capabilities. The parameters retrieved from the measurements are the sagitta and therefore the radius of curvature for different bending positions. The behavior of the variation of the shape of the mirror was also studied. The information gathered from our measurements will be used to optimize the final design of the bender.

  12. Measuring Growth and Decline in Visual-Motor Processes with the Bender-Gestalt Second Edition

    Science.gov (United States)

    Decker, Scott L.

    2008-01-01

    The purpose of this study is to develop a change-sensitive scale for evaluating developmental change in visual-motor ability across the life span. A partial-credit item-response model is used to estimate theta values for each age group between 4 and 90 using the Bender-Gestalt II standardization sample (N = 4,000). Results from this study suggest…

  13. Electrostatic Bender Fields, Optics, Aberrations, with Application to the Proton EDM Ring

    CERN Document Server

    Baartman, R

    2015-01-01

    Electrostatic bender optics are derived up to second order (third order in fields and the Hamiltonian) and applied to the proposed EDM proton ring. The results for linear optics agree with those already presented by V.\\ Lebedev (Nov.\\ 18, 2013). Second order optics is not sensitive to the shape of the fringe fields and formulas are given. It is shown that the proposed electrode shape that linearizes the vertical electric field is no advantage to this order.

  14. Bender-gradual scoring system: performance of Brazilian and Peruvian children.

    Science.gov (United States)

    dos Santos, Acácia Aparecida Angeli; Noronha, Ana Paula Porto; Rueda, Fabián Javier Marín; Segovia, José Livia

    2014-06-01

    This is a transcultural study of a sample of Peruvian and Brazilian children using the Bender-Gradual Scoring System (B-SPG), which considers shape distortion as the only aspect to be analyzed, assuming that perceptual-motor maturity is independent of cultural context. The study verified that the scoring system has psychometric qualities such that it may be applied in another country. The sample consisted of 231 children, ages 6 to 10 yr., 108 from different districts of the province Lima in Peru, and 123 children from three states in Brazil. During test application, the figures were projected to children in groups. Scoring the protocols for errors was conducted by psychologists experienced in interpreting and correcting the Bender-SPG, who rigorously followed instructions in Portuguese and Spanish. The results obtained with Differential Item Functioning (DIF) analysis indicated that Figures 1 and 4 presented DIF, one favoring Brazilian children and the other Peruvian children. Thus, it was concluded that the overall scores did not favor either population and the Bender-SPG could be used to evaluate perceptual-motor maturity in both countries.

  15. Aspects of Perturbation theory in Quantum Mechanics: The BenderWu Mathematica package

    CERN Document Server

    Sulejmanpasic, Tin

    2016-01-01

    We discuss a general setup which allows the study of the perturbation theory of an arbitrary, locally harmonic 1D quantum mechanical potential as well as its multi-variable (many-body) generalization. The latter may form a prototype for regularized quantum field theory. We first generalize the method of Bender-Wu, and derive exact recursion relations which allow the determination of the perturbative wave-function and energy corrections to an arbitrary order, at least in principle. For 1D systems, we implement these equations in an easy to use Mathematica package we call BenderWu. Our package enables quick home-computer computation of high orders of perturbation theory (about 100 orders in 10-30 seconds, and 250 orders in 1-2h) and enables practical study of a large class of problems in Quantum Mechanics. We have two hopes concerning the BenderWu package. One is that due to resurgence, large amount of non-perturbative information, such as non-perturbative energies and wave-functions (e.g. WKB wave functions), ...

  16. The first mesozoic ants.

    Science.gov (United States)

    Wilson, E O; Carpenter, F M; Brown, W L

    1967-09-01

    Two worker ants preserved in amber of Upper Cretaceous age have been found in New Jersey. They are the first undisputed remains of social insects of Mesozoic age, extending the existence of social life in insects back to approximately 100 million years. They are also the earliest known fossils that can be assigned with certainty to aculeate Hymenoptera. The species, Sphecomyrma freyi, is considered to represent a new subfamily (Sphecomyrminae), more primitive than any previously known ant group. It forms a near-perfect link between certain nonsocial tiphiid wasps and the most primitive myrmecioid ants.

  17. Field techniques for sampling ants

    Science.gov (United States)

    Ants occur in most environments and ecologists ask a diverse array of questions involving ants. Thus, a key consideration in ant studies is to match the environment and question (and associated environmental variables) to the ant sampling technique. Since each technique has distinct limitations, usi...

  18. Comparison of the effects of PEEP levels on respiratory mechanics and elimination of volatile anesthetic agents in patients undergoing laparoscopic cholecystectomy; a prospective, randomized, clinical trial.

    Science.gov (United States)

    Arinalp, Hüsnü Mert; Bakan, Nurten; Karaören, Gülşah; Şahin, Ömer Torun; Çeliksoy, Emre

    2016-06-23

    In laparoscopic procedures, intraabdominal carbon dioxide (CO2) insufflation can cause decreased compliance, increased airway resistance, and impaired ventilation-perfusion ratios. We aimed to investigate the effects of intraoperative positive end-expiratory pressure (PEEP) treatment on respiratory dynamics and elimination time of volatile anesthetic agents. In the present study, 75 ASA I-II patients were randomized into 3 groups to receive 0 cmH2O PEEP (group I), 5 cmH2O PEEP (group II), or 8 cmH2O PEEP (group III). Hemodynamic parameters, peak and plateau inspiratory airway pressures (Ppeak, Pplateau), compliance values, the ratio of the fractions of inspired and expired concentration of sevoflurane (Fi/Fexp sevoflurane) at 1 MAC, times from 1 to 0.3 and 0.1 MAC and values for pulmonary function tests (PFT) were recorded. Ppeak and Pplateau in group III were higher; compliance values in group I and the extent of reduction in postoperative forced vital capacity (FVC) in group III were lower than those in the other groups (P < 0.05). No significant difference was observed between the groups regarding times from 1 to 0.3 MAC and times from 0.3 to 0.1 MAC. It was found that 8 cmH2O PEEP increased compliance without clinically significant pulmonary deterioration and that 8 cmH2O PEEP led to less impairment in postoperative PFTs compared to 0 and 5 cmH2O PEEP but had no effect on sevoflurane elimination time.

  19. Semantic analysis according to Peep Koort--a substance-oriented research methodology.

    Science.gov (United States)

    Sivonen, Kerstin; Kasén, Anne; Eriksson, Katie

    2010-12-01

    The aim of this article is to describe the hermeneutic semantic analysis created by professor Peep Koort (1920-1977) and to discuss it as a methodology for research within caring science. The methodology is developed with a hermeneutic approach that differs from the traditions of semantic analysis in philosophy or linguistics. The research objects are core concepts and theoretical constructs (originally within the academic discipline of education science, later on within the academic discipline of caring science), focusing deeper understanding of essential meaning content when developing a discipline. The qualitative methodology of hermeneutic semantic analysis is described step by step as created by Koort, interpreted and developed by the authors. An etymological investigation and an analysis of synonymy between related concepts within a conceptual family guides the researcher to understand and discriminate conceptual dimensions of meaning content connected to the word studied, thus giving opportunities to summarise it in a theoretical definition, a discovery that can be tested in varying contexts. From a caring science perspective, we find the hermeneutic methodology of semantic analysis fruitful and suitable for researchers developing their understanding of core concepts and theoretical constructs connected to the development of the academic discipline.

  20. Sick ants become unsociable.

    Science.gov (United States)

    Bos, N; Lefèvre, T; Jensen, A B; d'Ettorre, P

    2012-02-01

    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 provide evidence for the evolution of unsociability following pathogen infection in a social animal and suggest an important role of inclusive fitness in driving such evolution.

  1. Construct validity of the Bender-Gestalt II: comparison with Wechsler Intelligence Scale for Children-III.

    Science.gov (United States)

    Decker, Scott L; Allen, Ryan; Choca, James P

    2006-02-01

    This study investigated the relationships of visuomotor constructs as measured by the Bender-Gestalt II with the subtests of the WISC-III. A factor analysis included the standardized Copy and Recall scores of the Bender-Gestalt II and subtest scores of the WISC-III. The Copy score was predicted to load on measures of visual and spatial thinking and the Recall score on a short-term memory factor. The results of a principal components analysis suggest a four-factor solution with the Bender-Gestalt II Copy score loading on a visual and spatial thinking factor primarily with WISC-III Perceptual Organization subtests. The Recall score loaded on a visual and spatial thinking factor as well as a short-term memory factor with the WISC-III Digit Span subtest. The results suggest the Bender-Gestalt II Copy subtest shared commonality with the visual and spatial tasks given the similarity in the visuomotor demands of each test and was less influenced by processing speed or cultural knowledge than other tests on the visual and spatial thinking factor. Also, results suggest Bender-Gestalt II Recall measures elements of both visual and spatial thinking as well as aspects of short-term memory and memory retrieval. Clinical guidelines for co-administration and underlying processing demands are discussed.

  2. Bender Visual-Motor Gestalt Test in adolescents: relationship between visual-motor development and the Tanner Stages.

    Science.gov (United States)

    Keppeke, Lívia de Freitas; Cintra, Isa de Pádua; Schoen, Teresa Helena

    2013-08-01

    Visual-motor skill is fundamental to human development and is an important component of psychological evaluations. The goal of the present study was to determine whether there is a correlation between visual-motor development, as measured by the Bender Visual-Motor Gestalt Test (Bender test), and sexual maturity in adolescents, based on the Tanner Stages in Adolescents. 134 adolescents from 10 to 15 years of age participated in the study. The Bender test and the Raven's Progressive Matrices Test were employed. The measures were administered individually and information on sexual maturity and the presence of developmental disorders was collected from medical charts. The results of the Bender test were not affected by gender, age, schooling, or changes stemming from puberty, but were significantly affected by having repeated a school year and by developmental disorders. An association was found with Raven's scores. The Bender test proved sensitive to developmental disorders in adolescence. No association was found between visual-motor development and sexual maturity in adolescents.

  3. A Comparative Analysis of the Bender-Gestalt and Beery/Buktenica Tests of Visual-Motor Integration as a Function of Grade Level for Regular Education Students.

    Science.gov (United States)

    Lehman, Joanne; Breen, Michael J.

    1982-01-01

    Regular education students (N=125) in grades K-3 were administered the Bender-Gestalt and Beery/Buktenica tests of visual-motor integration. Found significant differences between the mean Bender and Beery age equivalent scores at each grade level. Discusses implications for their utilization in assessing fine motor readiness development.…

  4. The Bender Gestalt Test with the Human Figure Drawing Test for Young School Children. A Manual for Use with the Koppitz Scoring System.

    Science.gov (United States)

    Koppitz, Elizabeth Munsterberg

    Presented is a manual for scoring the Bender Gestalt Test and the Human Figure Drawing Test for screening and diagnostic uses with emotionally disturbed, brain damaged, or perceptually handicapped 5- to 11-year-old children. Given are suggestions for administering and scoring the Bender test which examines distortion of shape, rotation,…

  5. FCT (functional computed tomography) evaluation of the lung volumes at different PEEP (positive-end expiratory pressure) ventilation pattern, in mechanical ventilated patients

    Energy Technology Data Exchange (ETDEWEB)

    Papi, M.G.; Di Segni, R.; Mazzetti, G.; Staffa, F. [Dept. of Radiology, S. Giovanni HS, Rome (Italy); Conforto, F.; Calimici, R.; Salvi, A. [Dept. of Anesthesiology, S. Giovanni HS, Rome (Italy); Matteucci, G. [Dept. of Pneumology, S. Giovanni HS, Rome (Italy)

    2007-06-15

    Purpose To evaluate with FCT (functional computed tomography) total lung volume and fractional lung volumes at different PEEP (positive end expiratory pressure) values in acute mechanically ventilated patients. Methods Nine ICU (intensive care unity) patients (1 lung pneumonia, 2 polytrauma, 2 sepsis, 3 brain surgery, 1 pulmonary embolism); mean age 48 {+-} 15 years, 6 male, 3 female; GE 16 MDCT scan was performed with acquisition from apex to diaphragma in seven seca at different PEEP values. Raw CT data were analysed by an advantage workstation to obtain volume density masks and histograms of both lungs and each lung and these density ranges were applied: - 1000 - 950 = hyper-ventilated lung, -900 - 650 well aerated lung, -950 - 500 all aerated lung, -500 + 200 lung tissue. Total and fractional lung volumes, Hounsfield unit (HU) were calculated and compared at different PEEP values (0, 5, 10, 15 cm H{sub 2}O). In four patients lung volumes were compared between the more and the less involved lung at increased PEEP. Statistic analysis: comparison means-medians tests. Results Data calculated at five PEEP showed unexpected decrease of total lung volume and increase of lung density (HU); proportionally no significant improvement of oxigenation. (orig.)

  6. Record dynamics in ants.

    Directory of Open Access Journals (Sweden)

    Thomas O Richardson

    Full Text Available The success of social animals (including ourselves can be attributed to efficiencies that arise from a division of labour. Many animal societies have a communal nest which certain individuals must leave to perform external tasks, for example foraging or patrolling. Staying at home to care for young or leaving to find food is one of the most fundamental divisions of labour. It is also often a choice between safety and danger. Here we explore the regulation of departures from ant nests. We consider the extreme situation in which no one returns and show experimentally that exiting decisions seem to be governed by fluctuating record signals and ant-ant interactions. A record signal is a new 'high water mark' in the history of a system. An ant exiting the nest only when the record signal reaches a level it has never perceived before could be a very effective mechanism to postpone, until the last possible moment, a potentially fatal decision. We also show that record dynamics may be involved in first exits by individually tagged ants even when their nest mates are allowed to re-enter the nest. So record dynamics may play a role in allocating individuals to tasks, both in emergencies and in everyday life. The dynamics of several complex but purely physical systems are also based on record signals but this is the first time they have been experimentally shown in a biological system.

  7. Utilization of Anting-Anting (Acalypha indica) Leaves as Antibacterial

    Science.gov (United States)

    Batubara, Irmanida; Wahyuni, Wulan Tri; Firdaus, Imam

    2016-01-01

    Anting-anting (Acalypha indica) plants is a species of plant having catkin type of inflorescence. This research aims to utilize anting-anting as antibacterial toward Streptococcus mutans and degradation of biofilm on teeth. Anting-anting leaves were extracted by maceration technique using methanol, chloroform, and n-hexane. Antibacterial and biofilm degradation assays were performed using microdilution technique with 96 well. n-Hexane extracts of anting-anting leaves gave the best antibacterial potency with minimum inhibitory concentration and minimum bactericidal concentration value of 500 μg/mL and exhibited good biofilm degradation activity. Fraction of F3 obtained from fractionation of n-hexane's extract with column chromatography was a potential for degradation of biofilm with IC50 value of 56.82 μg/mL. Alkaloid was suggested as antibacterial and degradation of biofilm in the active fraction.

  8. CONFIABILIDAD INTERCALIFICADORES Y VALIDEZ DE CONSTRUCTO DEL TEST GESTÁLTICO DE BENDER ( SEGUNDA VERSIÓN )

    OpenAIRE

    CÉSAR MERINO SOTO; RYAN A. ALLEN

    2013-01-01

    Hace algunos años, se ha publicado el nuevo Test Gestáltico de Bender, segunda versión (Ben- der-II). Esta nueva versión usa el Sistema de Calificación Global (SCG) para obtener los pun- tajes, que enfatiza la reproducción exacta de los diseños; junto con otros cambios estructurales, consiste en la mayor modificación realizada al Test de Bender para evaluar la habilidad visomo- tora en varias etapas del desarrollo humano. Pero aún hay pocas investigaciones que han estudiado su funcionamiento ...

  9. The Bender Gestalt test for 5- to 15-year old Brazilian children: norms and validity.

    Science.gov (United States)

    Brito, G N; Santos, T R

    1996-11-01

    Norms for two modalities (normal and stress) of the Bender Gestalt test were developed for the neuropsychological assessment of children in the greater Rio de Janeiro area. For each modality, a measure of performance, a measure of speed and a measure of emotional disturbance were obtained. A total of 398 children (199 males and 199 females), 5 to 15 years old, who were attending a public school in Niterói were the subjects of this study. Analysis of the data revealed that age, but not sex, had a significant effect on performance, but not on speed, in both modalities such that older children made fewer errors than younger children. Also, the number of emotional indicators significantly decreased with age. Additionally, boys needed more time to complete the normal modality than girls, and showed a higher number of emotional indicators in both modalities. The Bender test was found to be valid in the sense that children who had failed at least one grade in school performed worse than those who had not. The number of emotional indicators was shown to be valid since it was significantly correlated with factors such as hyperactivity-conduct problem, and independent functioning, and inattention of the Composite Teacher Rating Scale (Brito GNO and Pinto RCA (1991). Journal of Clinical and Experimental Neuropsychology, 13: 417-418). We conclude that the Bender test is valid for use in schoolchildren, and the number of emotional indicators is valid as an index of psychopathology, but sex and age should be considered when using the norms in Brazil.

  10. A Benders decomposition-based Matheuristic for the Cardinality Constrained Shift Design Problem

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Larsen, Jesper; Range, Troels Martin

    . A shift type is a consecutive sequence of time periods that adheres to legal and union rules and can be assigned to an employee on any day. In this paper we introduce the Cardinality Constrained Shift Design Problem; a variant of the Shift Design Problem in which the number of permitted shift types...... the problem. Furthermore, we argue that an important step in this approach is finding dual alternative optimal solutions to the Benders subproblems and describe an approach to obtain a diverse set of these. Numerical tests show that the described methodology significantly outperforms a commercial Mixed...

  11. The stability of four kinds of perceptual erros on the Bender-Gestalt.

    Science.gov (United States)

    Engin, A W; Wallbrown, F H

    1976-09-01

    The test-retest reliability of the Bender-Gestalt Test was investigated for 157 second graders from two middle-class schools. The test-retest interval ranged from 11 days through 15 days. Testing was conducted in accordance with the Koppitz procedure, but errors of distortion, rotation, integration, and preservation were determined separately. The total time required to reproduce the designs were also recorded. The reliability estimate for the Koppitz score was generally satisfactory, but the estimates obtained for the four separate error categories and total working time were substantially smaller.

  12. Single-Facility Scheduling over Long Time Horizons by Logic-Based Benders Decomposition

    Science.gov (United States)

    Coban, Elvin; Hooker, John N.

    Logic-based Benders decomposition can combine mixed integer programming and constraint programming to solve planning and scheduling problems much faster than either method alone. We find that a similar technique can be beneficial for solving pure scheduling problems as the problem size scales up. We solve single-facility non-preemptive scheduling problems with time windows and long time horizons that are divided into segments separated by shutdown times (such as weekends). The objective is to find feasible solutions, minimize makespan, or minimize total tardiness.

  13. Multivariable fractional polynomial interaction to investigate continuous effect modifiers in a meta-analysis on higher versus lower PEEP for patients with ARDS

    Science.gov (United States)

    Kasenda, Benjamin; Sauerbrei, Willi; Royston, Patrick; Mercat, Alain; Slutsky, Arthur S; Cook, Deborah; Guyatt, Gordon H; Brochard, Laurent; Richard, Jean-Christophe M; Stewart, Thomas E; Meade, Maureen; Briel, Matthias

    2016-01-01

    Objectives A recent individual patient data (IPD) meta-analysis suggested that patients with moderate or severe acute respiratory distress syndrome (ARDS) benefit from higher positive end-expiratory pressure (PEEP) ventilation strategies. However, thresholds for continuous variables (eg, hypoxaemia) are often arbitrary and linearity assumptions in regression approaches may not hold; the multivariable fractional polynomial interaction (MFPI) approach can address both problems. The objective of this study was to apply the MFPI approach to investigate interactions between four continuous patient baseline variables and higher versus lower PEEP on clinical outcomes. Setting Pooled data from three randomised trials in intensive care identified by a systematic review. Participants 2299 patients with acute lung injury requiring mechanical ventilation. Interventions Higher (N=1136) versus lower PEEP (N=1163) ventilation strategy. Outcome measures Prespecified outcomes included mortality, time to death and time-to-unassisted breathing. We examined the following continuous baseline characteristics as potential effect modifiers using MFPI: PaO2/FiO2 (arterial partial oxygen pressure/ fraction of inspired oxygen), oxygenation index, respiratory system compliance (tidal volume/(inspiratory plateau pressure−PEEP)) and body mass index (BMI). Results We found that for patients with PaO2/FiO2 below 150 mm Hg, but above 100 mm Hg or an oxygenation index above 12 (moderate ARDS), higher PEEP reduces hospital mortality, but the beneficial effect appears to level off for patients with very severe ARDS. Patients with mild ARDS (PaO2/FiO2 above 200 mm Hg or an oxygenation index below 10) do not seem to benefit from higher PEEP and might even be harmed. For patients with a respiratory system compliance above 40 mL/cm H2O or patients with a BMI above 35 kg/m2, we found a trend towards reduced mortality with higher PEEP, but there is very weak statistical confidence in

  14. 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

  15. 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

  16. 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), w...

  17. ANT i arbejdslivsforskningen

    DEFF Research Database (Denmark)

    2012-01-01

    for Tidsskrift for Arbejdsliv at stille skarpt på, hvorledes teknologi kan forstås og udforskes, og her står nyere teoridannelser som STS (Science- and Technology Studies) og ANT (Actor-Network Theory) centralt. Dette temanummer af tidsskriftet har derfor disse teorier og deres anvendelse i studier af arbejdsliv...

  18. Tiny, Powerful, Awesome Ants!

    Science.gov (United States)

    Tate, Kathleen

    2007-01-01

    Peering through a thematic science lens--elementary students embarked on a one-week study of ants during a month-long summer school program. This integrated unit addressed reading and writing skills while developing the science-process skills of observation, inferring, and communicating in a motivating and authentic way. Pre- and post-assessments…

  19. Some normative data on the Bender Gestalt test performance of Iranian children.

    Science.gov (United States)

    Yousefi, F; Shahim, S; Razavieh, A; Mehryar, A H; Hosseini, A A; Alborzi, S

    1992-11-01

    The Bender Gestalt test of visuomotor coordination was applied to a sample of Iranian children (N = 1,600) aged between 6.0 years and 10 years and 11 months attending grades 1 through 5 of 16 public primary schools in Shiraz city, southern Iran. The administration of the test and its scoring followed the standard procedures recommended by Koppitz. The reliability of the test in its new context was investigated through readministering it to a group of 60 children after four weeks, the r being .77. The validity of the test was established by comparing scores of children at different age levels and by correlating test results with marks obtained in two sets of examinations, results of Goodenough Harris Draw-A-Person Test and indices of parental education and occupation. The results are mostly in the expected direction and indicate that the Bender Gestalt test may be used as a simple measure of cognitive-intellectual development in Iran. Observed differences between Iranian norms and those of Koppitz (1963, 1975) for American children are briefly discussed and explained.

  20. Application of geometry based hysteresis modelling in compensation of hysteresis of piezo bender actuator

    Science.gov (United States)

    Milecki, Andrzej; Pelic, Marcin

    2016-10-01

    This paper presents results of studies of an application of a new method of piezo bender actuators modelling. A special hysteresis simulation model was developed and is presented. The model is based on a geometrical deformation of main hysteresis loop. The piezoelectric effect is described and the history of the hysteresis modelling is briefly reviewed. Firstly, a simple model for main loop modelling is proposed. Then, a geometrical description of the non-saturated hysteresis is presented and its modelling method is introduced. The modelling makes use of the function describing the geometrical shape of the two hysteresis main curves, which can be defined theoretically or obtained by measurement. These main curves are stored in the memory and transformed geometrically in order to obtain the minor curves. Such model was prepared in the Matlab-Simulink software, but can be easily implemented using any programming language and applied in an on-line controller. In comparison to the other known simulation methods, the one presented in the paper is easy to understand, and uses simple arithmetical equations, allowing to quickly obtain the inversed model of hysteresis. The inversed model was further used for compensation of a non-saturated hysteresis of the piezo bender actuator and results have also been presented in the paper.

  1. The Dynamics of Foraging Ants

    Science.gov (United States)

    Baxter, G. William

    2009-03-01

    We experimentally study the foraging of small black ants, Formicinae lasius flavus, in order to describe their foraging behavior mathematically. Individual ants are allowed to forage on a two-dimensional surface in the absence of any food sources. The position of the ant as a function of time is determined using a high-resolution digital camera. Analysis of the average square displacements of many ants suggests that the foraging strategy is a non-reversing random walk. Moreover, the ants do not retrace their steps to return home but instead continue the random walk until it brings them back near their starting point.

  2. Design, fabrication and testing of elliptical crystal bender for the EXAFS beam-line at INDUS-II synchrotron source

    Indian Academy of Sciences (India)

    N C Das; S N Jha; D Bhattacharyya; A K Poswal; A K Sinha; V K Mishra

    2004-10-01

    An extended X-ray absorption fine structure (EXAFS) beam-line for X-ray absorption studies using energy dispersive geometry and position sensitive detector is being developed for the INDUS-II synchrotron source. The optical design of the beam-line has been completed based on the working principle that a single crystal bent in the shape of an ellipse by a crystal bender would act as a dispersing as well as focusing element. The heart of the beam-line is the crystal bender which has been designed on the basis of the principle of four-point bending and has been fabricated indigenously. The crystal bender is capable of producing pre-defined elliptical curvature on a crystal surface by applying different couples at the two-ends of the crystal which has variable width along its length. The focusing property of the crystal bender has been tested using a laser source and has been compared with the theoretically simulated results.

  3. The Bender Gestalt and the Ravens Progressive Matrices Measures of Perceptual Behavior, Motor Behavior and Perceptual-Motor Behavior.

    Science.gov (United States)

    Roberds, Jeannette

    The scores of 79 second-grade pupils on the Ravens Colored Progressive Matrices and the Bender Gestalt were factor-analyzed using six different factor-analytic procedures. Sex, age, and vocabulary test scores were included in the analysis as marker variables. The original factor solutions were subjected to oblique transformation and the…

  4. The Bender Visual Motor Gestalt Test: Correlations with WISC-R and Attainment Measures in a Clinic Sample.

    Science.gov (United States)

    Hamer, Ann

    1988-01-01

    Use of the Bender Visual Motor Gestalt Test in Australia was studied by comparing it with existing research, scores on the Wechsler Intelligence Scale for Children-Revised (WISC-R), and other attainment tests. Subjects were 142 children aged 7-11 years. The suitability of the instrument in Australia is discussed. (SLD)

  5. The Feasibility of a Group Bender-Gestalt Test for Preschool and Primary School-Aged Children

    Science.gov (United States)

    McCarthy, Denis P.

    1975-01-01

    Study devised and tested a method for group administration of the Bender-Gestalt Test that would be feasible for screening large groups of beginning school-age children. Results indicate that the group method of presentation can yield results as valid and reliable as the traditional individual method of administration. (Author)

  6. Comparison of the Minnesota Percepto-Diagnostic Test-Revised and Bender-Gestalt in Predicting Achievement.

    Science.gov (United States)

    Fuller, Gerald B.; Vance, Booney

    1993-01-01

    Investigated whether Minnesota Percepto-Diagnostic Test-Revised (MPD-R) or Bender-Gestalt Test (BG) would more accurately predict achievement at first-, third-, and fifth-grade levels. Administered both tests to 84 children in counterbalanced order. Results indicated that MPD-R was better predictor of achievement than BG, especially at first- and…

  7. Memory-for-Designs, Bender-Gestalt, Trail Making Test, and WISC-R Performance of Retarded and Adequate Readers

    Science.gov (United States)

    McManis, Donald L.; And Others

    1978-01-01

    Twelve reading-disabled and 12 nondisabled boys, of average intellectual ability, in Grades 3 to 6 were compared on the Memory-For-Designs, Bender-Gestalt, Trail Making Test, and the 11 subtests of the Wechsler Intelligence Scale for Children--Revised (WISC-R). (Author)

  8. The Bender Gestalt Test: A Review of Reported Research with School-Age Subjects, 1966-1977

    Science.gov (United States)

    Buckley, Pepper D.

    1978-01-01

    The past 11 years of published research investigating the use of the Bender Gestalt Test with school-age children are reviewed. Seen as a psychometric instrument, scored according to standardized procedures, this recent work does not conclusively support use of the test for prediction of school achievement or emotional disturbance. (Author)

  9. The Visual Aural Digit Span Test and Bender Gestalt Test as Predictors of Wide Range Achievement Test-Revised Scores.

    Science.gov (United States)

    Smith, Teresa C.; Smith, Billy L.

    1988-01-01

    Examined Visual Aural Digit Span Test (VADS) and Bender-Gestalt (BG) scores as predictors of Wide Range Achievement Test-Revised (WRAT-R) scores among 115 elementary school students referred for low academic achievement. Divided children into three age groups. Results suggest BG and VADS Test can be effective screening devices for young children…

  10. Gifted Children and Visual-Motor Development: A Comparison of Bender-Gestalt and VMI Test Performance.

    Science.gov (United States)

    Knoff, Howard M.; Sperling, Barbara L.

    1986-01-01

    A sample of 63 gifted elementary-school students was administered the Bender Visual-Motor Gestalt Test and the Developmental Test of Visual-Motor Integration. Group results revealed no significant differences between the two tests, that they did correlate significantly, and that younger students had advanced visual-motor development when tested…

  11. Interscorer Reliability of the Modified Version of the Bender-Gestalt Test for Preschool and Primary School Children.

    Science.gov (United States)

    Fuller, Gerald B.; Vance, Booney

    1995-01-01

    Extends the reliability research of the Qualitative Scoring System for the Modified Version of the Bender-Gestalt Test. The test was administered to 48 children, and the 48 test protocols were scored independently by two psychologists using the Qualitative Scoring System. Results indicated that the scoring system is highly reliable. (JPS)

  12. Validity of the Draw-A-Person and Bender Gestalt Tests as Measures of Impulsivity with Adolescents.

    Science.gov (United States)

    Oas, Peter

    1984-01-01

    Designated 100 psychiatrically hospitalized and 114 nonhospitalized adolescents as impulsive or nonimpulsive and compared them to determine the validity of signs of impulsivity on the Draw-A-Person and Bender Gestalt tests. Signs of impulsivity and nonimpulsivity on these tests discriminated between impulsive and nonimpulsive adolescents with…

  13. Gifted Children and Visual-Motor Development: A Comparison of Bender-Gestalt and VMI Test Performance.

    Science.gov (United States)

    Knoff, Howard M.; Sperling, Barbara L.

    1986-01-01

    A sample of 63 gifted elementary-school students was administered the Bender Visual-Motor Gestalt Test and the Developmental Test of Visual-Motor Integration. Group results revealed no significant differences between the two tests, that they did correlate significantly, and that younger students had advanced visual-motor development when tested…

  14. A Comparison of the Koppitz and Hutt Techniques of Bender-Gestalt Administration Correlated with WISC-R Performance Scores.

    Science.gov (United States)

    Redfering, David L.; Collins, Jackie

    1982-01-01

    Forty elementary students were administered the Bender-Gestalt Test using two techniques: Koppitz routine instructions and the Hutt testing-the-limits method. The mean number of Koppitz errors was approximately two greater than the number obtained using the Hutt technique. (Author/BW)

  15. The Relationship between the Bender-Gestalt Test and the Marianne Frostig Developmental Test of Visual Perception.

    Science.gov (United States)

    O'Connor, William J.

    The relationship between the Bender-Gesalt Test was studied using the Koppitz Developmental Scoring System and the Marianne Frostig Developmental Test of Visual Perception in terms of age, sex, IQ, and socioeconomic status. A relationship to the Harrison Reading Readiness Test was also explored. Subjects were 89 first- and second-grade children…

  16. Expanded Koppitz Scoring System of the Bender Gestalt Visual-Motor Test for Adolescents: A Pilot Study.

    Science.gov (United States)

    Bolen, Larry M.; And Others

    1992-01-01

    Examined use of Bender Gestalt Visual-Motor Test with school-age adolescents over age 11. Mean error scores suggest that visual-motor development is not maturationally complete by age 11 years, 11 months. Suggests additional research focusing on extending normative sample or developing new scoring system for adolescents. (Author/NB)

  17. Relationship of Bender Gestalt Developmental Scores and Human Drawing Developmental Scores in a Sample of Turkish Preschool Children

    Science.gov (United States)

    Ozer, Serap

    2009-01-01

    The Bender Gestalt test and Human Drawings are frequently utilized tests in assessing school readiness in children. This study was a pilot attempt to evaluate these two tests in a Turkish sample as they relate to first grade behaviour as measured by teacher ratings. One hundred and five children were evaluated at the end of kindergarten using the…

  18. Visual-motor and executive functions in children born preterm: the Bender Visual Motor Gestalt Test revisited.

    Science.gov (United States)

    Böhm, Birgitta; Lundequist, Aiko; Smedler, Ann-Charlotte

    2010-10-01

    Visual-motor development and executive functions were investigated with the Bender Test at age 5½ years in 175 children born preterm and 125 full-term controls, within the longitudinal Stockholm Neonatal Project. Assessment also included WPPSI-R and NEPSY neuropsychological battery for ages 4-7 (Korkman, 1990). Bender protocols were scored according to Brannigan & Decker (2003), Koppitz (1963) and a complementary neuropsychological scoring system (ABC), aimed at executive functions and developed for this study. Bender results by all three scoring systems were strongly related to overall cognitive level (Performance IQ), in both groups. The preterm group displayed inferior visual-motor skills compared to controls also when controlling for IQ. The largest group differences were found on the ABC scoring, which shared unique variance with NEPSY tests of executive function. Multiple regression analyses showed that hyperactive behavior and inattention increased the risk for visual-motor deficits in children born preterm, whereas no added risk was seen among hyperactive term children. Gender differences favoring girls were strongest within the preterm group, presumably reflecting the specific vulnerability of preterm boys. The results indicate that preterm children develop a different neurobehavioral organization from children born at term, and that the Bender test with a neuropsychological scoring is a useful tool in developmental screening around school start.

  19. Simulation and optimization of a new focusing polarizing bender for the diffuse neutrons scattering spectrometer DNS at MLZ

    Science.gov (United States)

    Nemkovski, K.; Ioffe, A.; Su, Y.; Babcock, E.; Schweika, W.; Brückel, Th

    2017-06-01

    We present the concept and the results of the simulations of a new polarizer for the diffuse neutron scattering spectrometer DNS at MLZ. The concept of the polarizer is based on the idea of a bender made from the stack of the silicon wafers with a double-side supermirror polarizing coating and absorbing spacers in between. Owing to its compact design, such a system provides more free space for the arrangement of other instrument components. To reduce activation of the polarizer in the high intensity neutron beam of the DNS spectrometer we plan to use the Fe/Si supermirrors instead of currently used FeCoV/Ti:N ones. Using the VITESS simulation package we have performed simulations for horizontally focusing polarizing benders with different geometries in the combination with the double-focusing crystal monochromator of DNS. Neutron transmission and polarization efficiency as well as the effects of the focusing for convergent conventional C-benders and S-benders have been analyzed both for wedge-like and plane-parallel convergent geometries of the channels. The results of these simulations and the advantages/disadvantages of the various configurations are discussed.

  20. Relationship of Bender Gestalt Developmental Scores and Human Drawing Developmental Scores in a Sample of Turkish Preschool Children

    Science.gov (United States)

    Ozer, Serap

    2009-01-01

    The Bender Gestalt test and Human Drawings are frequently utilized tests in assessing school readiness in children. This study was a pilot attempt to evaluate these two tests in a Turkish sample as they relate to first grade behaviour as measured by teacher ratings. One hundred and five children were evaluated at the end of kindergarten using the…

  1. 基于ANSYS的一种螺旋焊管机座的强度分析%ANSYS-based Strength Analysis of Spiral Welded Pipe Bender Seat

    Institute of Scientific and Technical Information of China (English)

    虞兵; 陈靖芯; 马祥; 秦永法; 竺志大

    2013-01-01

    This paper simply introduces the components of the spiral welded pipe bender ,puts forward a way of structural strength analysis for spiral welded pipe bender seat ,and uses this method to analyse the strength of one spiral welded pipe bender seat .%  简单介绍了螺旋焊管机的组成,提出了一种螺旋焊管机座结构强度分析的计算方法,并且采用该方法对某款螺旋焊管机座进行了结构强度分析。

  2. "Ant-egg" cataract revisited

    DEFF Research Database (Denmark)

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

    2017-01-01

    PURPOSE: Hereditary congenital cataract varies immensely concerning location and form of the lens opacities. A specific and very rare phenotype is called "ant-egg" cataract first described in 1900. "Ant-eggs" have previously been examined using light microscopy, backscattered electron imaging and X......-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......-egg" structures in "ant-egg" cataract. Eighteen of these proteins are not natively found in the human lens. Moreover, "ant-eggs" do not vary over time, after cataract extraction, regarding size and location....

  3. Rasked vestlused. Kuidas ma talle seda ütlen / Irene Metsis, Sami Seppänen, Peep Sooman ; intervjueerinud Heli Lehtsaar

    Index Scriptorium Estoniae

    Metsis, Irene

    2009-01-01

    Skanska EMV administratsioonijuhi Irene Metsise, AS-i Elisa Eesti tegevdirektori Sami Seppäneni ja Pindi Kinnisvara juhatuse liikme Peep Soomani soovitused negatiivse sõnumi edastamiseks töötajale. Vt. samas: 4 nõuannet juhile, kuidas end keeruliseks vestluseks ette valmistada

  4. Estudio transcultural con la prueba de Bender: Sistema de puntuación gradual (Cross-Cultural Study with Bender Test- Gradual Scoring System

    Directory of Open Access Journals (Sweden)

    Fabián Javier Marín Rueda

    2013-12-01

    Full Text Available RESUMEN: El objetivo del presente estudio es comparar el desempeño en la Prueba Gestáltica Visomotriz de Bender - Sistema de Puntuación Gradual (B-SPG en un grupo de niños peruanos en función a los datos ofrecidos por el manual brasilero de la prueba. Participaron 82 niños, de ambos sexos, con edades entre los 8 y 10 años (M = 9.21, DT = 0.83. Los niños provenían de los distritos de Pueblo Libre (43.9% y Rímac (51.2%, de la provincia de Lima, así como también de Lima Metropolitana (4.9%. El B-SPG fue aplicado de forma colectiva. Los promedios de puntos obtenidos por los niños peruanos en el B-SPG fueron significativamente superiores a los obtenidos por los niños brasileros en cada una de las edades estudiadas. Se destaca la importancia de investigar evidencias de validez y de confiabilidad para que la prueba pueda ser usada de forma adecuada en el Perú, considerando las particularidades de desarrollo de los niños del país. ABSTRACT: The objective of the study is to compare performance on the Bender Visual Motor Gestalt test - system of Gradual punctuation (B-SPG in a group of Peruvian children in connection with the data provided by the Brazilian manual of the test. In this research 82 Peruvian children were involved, both sexes, with ages between 8 and 10 years (M = 9.21, DT = 0.83. The hildren came from the districts of Pueblo Libre (43.9% and Rimac (51.2% in the province of Lima, as well as from metropolitan Lima (4.9%. The B-SPG was collectively applied in the children’s schools. The average points earned by the Peruvian children in the B-SPG were significantly higher than those obtained by Brazilian children in each one of the ages studied. It emphasizes the importance of investigating evidence of validity and reliability, so that, the test can be used appropriately in Peru, considering the peculiarities of the development of children in the country.

  5. Ante la ley

    Directory of Open Access Journals (Sweden)

    Kafka Franz

    1999-12-01

    Full Text Available Ante las puertas de la ley hay un guardian. Un campesino se llega hasta ese guardian y le pide que le permita entra en la ley, pero el guardian le dice que por ahora no se lo puede permitir. El hombre reflexiona y entonces pregunta si podria entrar despues. Es posible -dice el guardian-; pero no ahora. La puerta de entrada a la ley esta abierta como siempre.

  6. 论电影受众的窥视审美体验%Discussion on Peep Aesthetic Experience of Film Audience

    Institute of Scientific and Technical Information of China (English)

    衣凤翱

    2011-01-01

    The understanding of image in the Psycho-analysis film theory is a process during which the study of object images is transformed into the study of main audiences. And it is an inevitable dialectical logic result during the histor- ical development, which pays attention to peep aesthetic experience of film audiences. In the psycho-analysis film theo- ry,the screen is considered as "mirror" that explains the occurrence mechanism of peep aesthetic experience of film audiences. And the understanding of film-" dream" becomes the key to peep aesthetic experience of film audiences. The peep aesthetic experience of film audiences that takes the peep as the psychological basis and the approval as the psychic mechanism is an important viewing psychological activity.%精神分析学电影理论对影像的理解是电影艺术研究逐渐由客体影像研究向主体受众研究转变的过程,其对电影受众的窥视审美体验的重视是一种辩证的历史发展逻辑的必然结果。精神分析学电影理论将银幕隐喻为“镜子”阐释了电影受众窥视审美体验的发生机制,而其对电影——“梦”的理解更成为电影受众窥视审美体验发生的关键。电影受众窥视审美体验的发生是受众以窥视为心理基础,以认同为心理机制的重要观影心理活动。

  7. Distributed nestmate recognition in ants.

    Science.gov (United States)

    Esponda, Fernando; Gordon, Deborah M

    2015-05-07

    We propose a distributed model of nestmate recognition, analogous to the one used by the vertebrate immune system, in which colony response results from the diverse reactions of many ants. The model describes how individual behaviour produces colony response to non-nestmates. No single ant knows the odour identity of the colony. Instead, colony identity is defined collectively by all the ants in the colony. Each ant responds to the odour of other ants by reference to its own unique decision boundary, which is a result of its experience of encounters with other ants. Each ant thus recognizes a particular set of chemical profiles as being those of non-nestmates. This model predicts, as experimental results have shown, that the outcome of behavioural assays is likely to be variable, that it depends on the number of ants tested, that response to non-nestmates changes over time and that it changes in response to the experience of individual ants. A distributed system allows a colony to identify non-nestmates without requiring that all individuals have the same complete information and helps to facilitate the tracking of changes in cuticular hydrocarbon profiles, because only a subset of ants must respond to provide an adequate response.

  8. "Ant-egg" cataract revisited.

    Science.gov (United States)

    Clemmensen, Kåre; Enghild, Jan J; Ivarsen, Anders; Riise, Ruth; Vorum, Henrik; Heegaard, Steffen

    2017-01-01

    Hereditary congenital cataract varies immensely concerning location and form of the lens opacities. A specific and very rare phenotype is called "ant-egg" cataract first described in 1900. "Ant-eggs" have previously been examined using light microscopy, backscattered electron imaging and X-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. "Ant-eggs" were examined using Heidelberg SPECTRALIS Optical Coherence Tomography (OCT)(Heidelberg Engineering, Heidelberg, Germany). Ten "ant-eggs" were extracted; four of these as well as control tissue were analyzed by mass spectrometry (AB Sciex). Proteins were identified and their approximate abundances were determined. Immunohistochemical staining was carried out on the remaining "ant-eggs" for cytokeratin and S100. In anterior OCT-images, the "ant-egg" structures are localized on the iris. Comparative pictures showed that they stayed in the same location for more than 45 years. Mass spectrometry of "ant-eggs" yielded a proteome of 56 different proteins. Eighteen of the 56 "ant-egg" proteins (32 %) were neither present in our controls nor in a known fetal lens proteome. Among these were cytokeratin and Matrix-Gla protein. Immunohistochemical reactions were positive for cytokeratin and S100. This study demonstrates the previously unknown protein composition of the "ant-egg" structures in "ant-egg" cataract. Eighteen of these proteins are not natively found in the human lens. Moreover, "ant-eggs" do not vary over time, after cataract extraction, regarding size and location.

  9. A Pilot Study of Visual-Motor Developmental Inter-Test Reliability: The Beery Developmental Test of Visual Motor Integration and the Bender Visual Motor Gestalt Test.

    Science.gov (United States)

    Porter, Gary L.; Binder, Dorothy M.

    1981-01-01

    To determine the intertest reliability of the Beery Developmental Test of Visual Motor Integration (VMI) and the Bender Visual Motor Gestalt Test (BGT), 64 six to nine year olds were administered both tests.

  10. A Review of the Bender Gestalt Test as a Screening Instrument for Brain Damage with School-Aged Children of Normal Intelligence Since 1970.

    Science.gov (United States)

    Eno, Larry; Deichmann, John

    1980-01-01

    All methods reviewed significantly discriminate between groups of brain damaged and unimpaired children. No method, however, provides successful predictive rates high enough to warrant the use of the Bender as the sole diagnostic instrument in individual cases. (Author)

  11. Vene teatri interjööride restaureerimine ja sisekujundus. Vabaduse väljak 5, Tallinn / Aivar Oja, Riin Luuk, Piret Bender...[jt.

    Index Scriptorium Estoniae

    2007-01-01

    5 värv. sisevaadet; sisekujundajad: A. Oja, R. Luuk (ajalooline osa), P. Bender (uus osa); siseviimistluse, maalingute ja valgustite restaureerimine: KAR Grupp; 1926. a. valminud hoone arhitekt: F. Skujinsh

  12. Stochastic Benders decomposition for the supply chain investment planning problem under demand uncertainty

    Directory of Open Access Journals (Sweden)

    Fabricio Oliveira

    2012-12-01

    Full Text Available This paper presents the application of a stochastic Benders decomposition algorithm for the problem of supply chain investment planning under uncertainty applied to the petroleum byproducts supply chain. The uncertainty considered is related with the unknown demand levels for oil products. For this purpose, a model was developed based on two-stage stochastic programming. It is proposed two different solution methodologies, one based on the classical cutting plane approach presented by Van Slyke & Wets (1969, and other, based on a multi cut extension of it, firstly introduced by Birge & Louveaux (1988. The methods were evaluated on a real sized case study. Preliminary numerical results obtained from computational experiments are encouraging.

  13. The Bender-Gestalt psychopathology scale: failure to infer validity in a school-aged sample.

    Science.gov (United States)

    Rossini, E D

    1993-06-01

    The concurrent validity of Hutt's (1977) empirical psychopathology scale of the Bender Visual-Motor Gestalt Test was evaluated among three groups of younger school-aged children within the 7-to-10- year age range (M = 109.1): adjustment disordered, conduct disordered, and nonclinical controls (n = 40/group). Excellent interscorer reliability was achieved with approximately 2 hr of self-study of the scoring manual. Although the conduct-disordered group was significantly more immature on Koppitz' Developmental Scoring System, there were no significant differences among groups on the psychopathology scale when visual-motor development was covaried (M = 50.5). This was an unexpected result, given Hutt's initial validation study among school-aged children. The psychopathology scale was not inferred to be valid among adolescents in the only known concurrent validation study. Pending supportive validation research, the psychopathology scale should not be employed in the clinical assessment of younger school-aged children.

  14. Effects of serial position on Bender-Gestalt errors using Koppitz's criteria.

    Science.gov (United States)

    Nyfield, B; Patalano, F

    1998-12-01

    The validity of the Koppitz Developmental scoring system in identifying organic impairment among functionally impaired adolescents was challenged in the current study. It was proposed that there are two distinct subtypes of errors in this system: those that are valid indicators of organic impairment (Category A) and those which are not but occur as a function of specific emotional factors (Category B). 46 male adolescents with a primary diagnosis of Conduct Disorder, Oppositional Defiant Disorder, or Attention-Deficit Hyperactivity Disorder were administered the Bender-Gestalt once using the standard order of administration and once in reverse order. It was hypothesized that more errors would be committed on cards presented later than those presented earlier in sequence for Category B but not Category A errors. Analysis provided partial support for this hypothesis.

  15. The Bender-Gestalt as a method of personality assessment with adolescents.

    Science.gov (United States)

    Belter, R W; McIntosh, J A; Finch, A J; Williams, L D; Edwards, G L

    1989-05-01

    Normative data are presented for two Bender-Gestalt scoring systems with a sample of "normal" controls (n = 150), emotionally disturbed (n = 140), and mentally retarded/neurologically impaired (MR/NI) adolescents (n = 47), aged 12 to 17 years. The results failed to support the use of Hutt's (1985) Psychopathology Scale and Adolescent Configuration in differentiating the "normal" and emotionally disturbed groups, but did support their use in differentiating the MR/NI group from the other two. The Hutt scores also were found to be related inversely to age and IQ. By contrast, the Koppitz scores differentiated the three groups from each other and were not related significantly to IQ. The results supported limited use of Koppitz's (1975) Emotional Indicators as a "sign" approach to brief screening for emotional disturbance in adolescents.

  16. BENDER GESTALT VISUALMOTOR TEST AND CARAS TEST: A EXAM OF CONSTRUCT VALIDITY

    Directory of Open Access Journals (Sweden)

    Cesar Merino Soto

    2011-12-01

    Full Text Available Research with new versions of the Bender Gestalt Test (TGB has hardly attracted attention to the researchers of the Hispanic world, onsidering that this test is one of the most widely used psychological assessments. This study evaluates the construct validity of the modified version of TGB for children, elative to sustainedattention assessed by the Caras Test. Both tests were applied to 90 children, aged between 5 and 8, in standardized conditions. The esults indicate that the shared variance between the two measures is zero, even when applied disattenuated correlations for measurement error; also, no non-linear patterns were detected between the two variables. These correlations were consistent in the total sample and among subgroups of children. We discuss these results with respect to the limits of validity of this modified version of TGB in the Spanish language.

  17. Design, construction, and measurements of a bender, which provide constant position of the central part of the crystal monocromator during bending process (abstract)

    Science.gov (United States)

    Artemev, A.; Artemiev, N.; Busetto, E.; Franc, F.; Hrdý, J.; Mrázek, D.; Savoia, A.

    2002-03-01

    The bender described is a part of the double crystal monochromator for the QUICKEXAFS spectrometer, which is under development for ELETTRA. Technical specification for the bender include the following: constant position of the central point of the crystal during the bending process, the full size of the crystal must be as small as possible in the dynamic bending process, and the bender must be highly vacuum compatible. To satisfy all of these demands we propose a new scheme for a bender of rectangular crystal with four living supports. The bender has two inner wings, which bear two inner crystal supports, and two outer wings, which bear two outer supports. These wings are moved by two cones placed on the same rod. The cones have different profiles. In order to keep the central part of the crystal in a constant position during the bending process these cone profiles are designed and manufactured in a very special way. Measurements of the bender characteristics were made with the help of a test bench. Instead of a Si single crystal we used a bronze plate of the same size, which had very similar elastic constants. The full scattering of the position of the central part of the bronze plate during the bending process is less then 100 μm. The measured profile of the plate bent to about 506 mm was compared with a circle fitted by the least square method. The relative difference between measured and fitted radius appeared to be about 10-5.

  18. Diagnosis of OCD Patients Using Drawing Features of Bender Gestalt Shapes

    Directory of Open Access Journals (Sweden)

    Boostani R.

    2017-03-01

    Full Text Available Background: Since psychological tests such as questionnaire or drawing tests are almost qualitative, their results carry a degree of uncertainty and sometimes subjectivity. The deficiency of all drawing tests is that the assessment is carried out after drawing the objects and lots of information such as pen angle, speed, curvature and pressure are missed through the test. In other words, the psychologists cannot assess their patients while running the tests. One of the famous drawing tests to measure the degree of Obsession Compulsion Disorder (OCD is the Bender Gestalt, though its reliability is not promising. Objective: The main objective of this study is to make the Bender Gestalt test quantitative; therefore, an optical pen along with a digital tablet is utilized to preserve the key drawing features of OCD patients during the test. Materials and Methods: Among a large population of patients who referred to a special clinic of OCD, 50 under therapy subjects voluntarily took part in this study. In contrast, 50 subjects with no sign of OCD performed the test as a control group. This test contains 9 shapes and the participants were not constraint to draw the shapes in a certain interval of time; consequently, to classify the stream of feature vectors (samples through drawing Hidden Markov Model (HMM is employed and its flexibility increased by incorporating the fuzzy technique into its learning scheme. Results: Applying fuzzy HMM classifier to the data stream of subjects could classify two groups up to 95.2% accuracy, whereas the results by applying the standard HMM resulted in 94.5%. In addition, multi-layer perceptron (MLP, as a strong static classifier, is applied to the features and resulted in 86.6% accuracy. Conclusion: Applying the pair of T-test to the results implies a significant supremacy of the fuzzy HMM to the standard HMM and MLP classifiers.

  19. Diagnosis of the OCD Patients using Drawing Features of the Bender Gestalt Shapes.

    Science.gov (United States)

    Boostani, R; Asadi, F; Mohammadi, N

    2017-03-01

    Since psychological tests such as questionnaire or drawing tests are almost qualitative, their results carry a degree of uncertainty and sometimes subjectivity. The deficiency of all drawing tests is that the assessment is carried out after drawing the objects and lots of information such as pen angle, speed, curvature and pressure are missed through the test. In other words, the psychologists cannot assess their patients while running the tests. One of the famous drawing tests to measure the degree of Obsession Compulsion Disorder (OCD) is the Bender Gestalt, though its reliability is not promising. The main objective of this study is to make the Bender Gestalt test quantitative; therefore, an optical pen along with a digital tablet is utilized to preserve the key drawing features of OCD patients during the test. Among a large population of patients who referred to a special clinic of OCD, 50 under therapy subjects voluntarily took part in this study. In contrast, 50 subjects with no sign of OCD performed the test as a control group. This test contains 9 shapes and the participants were not constraint to draw the shapes in a certain interval of time; consequently, to classify the stream of feature vectors (samples through drawing) Hidden Markov Model (HMM) is employed and its flexibility increased by incorporating the fuzzy technique into its learning scheme. Applying fuzzy HMM classifier to the data stream of subjects could classify two groups up to 95.2% accuracy, whereas the results by applying the standard HMM resulted in 94.5%. In addition, multi-layer perceptron (MLP), as a strong static classifier, is applied to the features and resulted in 86.6% accuracy. Applying the pair of T-test to the results implies a significant supremacy of the fuzzy HMM to the standard HMM and MLP classifiers.

  20. Fender Benders

    Science.gov (United States)

    Nelken, Miranda

    2009-01-01

    This article presents a lesson that allows third and fourth graders to forge the steel bodies of automobiles through repousse, the art of applying pressure to metal with a wooden point. In this lesson, the students draw cars paired with a landscape, making the road trip an adventure in drawing. Both parts of the lesson challenge students'…

  1. Fender Benders

    Science.gov (United States)

    Nelken, Miranda

    2009-01-01

    This article presents a lesson that allows third and fourth graders to forge the steel bodies of automobiles through repousse, the art of applying pressure to metal with a wooden point. In this lesson, the students draw cars paired with a landscape, making the road trip an adventure in drawing. Both parts of the lesson challenge students'…

  2. O Teste Gestáltico Visomotor de Bender na avaliação clínica de Crianças Bender Visual-motor Gestalt Test in the Children's Clinical Assessment

    OpenAIRE

    Roselaine Berenice Ferreira; Cristiane Friedrich Feil; Maria Lucia Tiellet Nunes

    2009-01-01

    Este estudo avaliou os erros mais freqüentes cometidos por crianças no Bender, pelo método Koppitz, e identificou sua relação com as variáveis idade e sexo. Analisou-se 1111 protocolos de avaliação psicológica, contemplando meninos e meninas, com idades entre cinco e doze anos, os quais apresentavam dificuldades emocionais, cognitivas e neurológicas, compondo uma amostra clínica. Constatou-se que os erros mais comuns frente à cópia do Bender foram a Distorção da Forma nas figuras 7 e 8 e a Ro...

  3. Kas omakeelsel haridusel ja teadusel on tulevikku? / Kirsti Siitonen, Jolanta Zabarskaite, Josep Soler-Carbonell, Rainer Enrique Hamel ; intervjueerinud Peep Nemvalts ; tõlkinud Doris Kareva, Aili Künstler

    Index Scriptorium Estoniae

    2011-01-01

    TLÜ teaduskeelekeskus korraldas koos TLÜ eesti keele ja kultuuri instituudiga 29. ja 30. augustil rahvusvahelise konverentsi "Rahvuskeeled teaduses ja kõrghariduses". Sel teemal vastavad TLÜ teaduskeelekeskuse juhataja Peep Nemvaltsi küsimustele konverentsi rahvusvahelised esinejad

  4. Mida arvate ideest, et kõrgkoole võiks juhtida ülikoolivälistest inimestest koosnev nõukogu? / Jaak Aaviksoo, Maris Mälzer, Peeter Kreitzberg, Peep Sürje

    Index Scriptorium Estoniae

    2010-01-01

    Küsimusele vastavad Tartu Ülikooli eelmine rektor Jaak Aaviksoo, Eesti Üliõpilaskondade Liidu esimees Maris Mälzer, Riigikogu kultuurikomisjoni esimees Peeter Kreitzberg ja Tallinna Tehnikaülikooli rektor Peep Sürje

  5. Kas omakeelsel haridusel ja teadusel on tulevikku? / Kirsti Siitonen, Jolanta Zabarskaite, Josep Soler-Carbonell, Rainer Enrique Hamel ; intervjueerinud Peep Nemvalts ; tõlkinud Doris Kareva, Aili Künstler

    Index Scriptorium Estoniae

    2011-01-01

    TLÜ teaduskeelekeskus korraldas koos TLÜ eesti keele ja kultuuri instituudiga 29. ja 30. augustil rahvusvahelise konverentsi "Rahvuskeeled teaduses ja kõrghariduses". Sel teemal vastavad TLÜ teaduskeelekeskuse juhataja Peep Nemvaltsi küsimustele konverentsi rahvusvahelised esinejad

  6. Mida arvate ideest, et kõrgkoole võiks juhtida ülikoolivälistest inimestest koosnev nõukogu? / Jaak Aaviksoo, Maris Mälzer, Peeter Kreitzberg, Peep Sürje

    Index Scriptorium Estoniae

    2010-01-01

    Küsimusele vastavad Tartu Ülikooli eelmine rektor Jaak Aaviksoo, Eesti Üliõpilaskondade Liidu esimees Maris Mälzer, Riigikogu kultuurikomisjoni esimees Peeter Kreitzberg ja Tallinna Tehnikaülikooli rektor Peep Sürje

  7. O Teste Gestáltico Visomotor de Bender na avaliação clínica de Crianças Bender Visual-motor Gestalt Test in the Children's Clinical Assessment

    Directory of Open Access Journals (Sweden)

    Roselaine Berenice Ferreira

    2009-08-01

    Full Text Available Este estudo avaliou os erros mais freqüentes cometidos por crianças no Bender, pelo método Koppitz, e identificou sua relação com as variáveis idade e sexo. Analisou-se 1111 protocolos de avaliação psicológica, contemplando meninos e meninas, com idades entre cinco e doze anos, os quais apresentavam dificuldades emocionais, cognitivas e neurológicas, compondo uma amostra clínica. Constatou-se que os erros mais comuns frente à cópia do Bender foram a Distorção da Forma nas figuras 7 e 8 e a Rotação na figura 7. Através do teste do Qui-quadrado identificou-se relação significativa entre erros nas figuras A, 1, 2, 4, 6, 7 e 8 e a variável idade (p=0,000. A variável sexo apresentou correlação significativa somente em erros nas figuras 4 e 7 no item rotação (pThis study discusses the most frequent errors committed by children in the Bender Test, assessed by the Koppitz method, and identified the correlation regarding age and sex. 1111 psychological assessment protocols were examined, including boys and girls, aged five and twelve years, which had emotional, cognitive and neurological difficulties, composing a clinical sample. The most frequent errors in the Bender test were distortion of form in Figures 7 and 8, and Rotation in Figure 7. Using Qui-square test was identified a significant relationship between errors in Figures A, 1, 2, 4, 6, 7 and 8 and variable age (p = 0000 was found. The variable sex showed significant correlation only in error of Figures 4 and 7 on the rotation item (p <0005.

  8. UN ANÁLISIS NO PARAMÉTRICO DE ÍTEMS DE LA PRUEBA DEL BENDER/A NONPARAMETRIC ITEM ANALYSIS OF THE BENDER GESTALT TEST MODIFIED

    Directory of Open Access Journals (Sweden)

    César Merino Soto

    2009-05-01

    Full Text Available Resumen:La presente investigación hace un estudio psicométrico de un nuevo sistema de calificación de la Prueba Gestáltica del Bendermodificada para niños, que es el Sistema de Calificación Cualitativa (Brannigan y Brunner, 2002, en un muestra de 244 niñosingresantes a primer grado de primaria en cuatro colegios públicos, ubicados en Lima. El enfoque usado es un análisis noparamétrico de ítems mediante el programa Testgraf (Ramsay, 1991. Los resultados indican niveles apropiados deconsistencia interna, identificándose la unidimensionalidad, y el buen nivel discriminativo de las categorías de calificación deeste Sistema Cualitativo. No se hallaron diferencias demográficas respecto al género ni la edad. Se discuten los presenteshallazgos en el contexto del potencial uso del Sistema de Calificación Cualitativa y del análisis no paramétrico de ítems en lainvestigación psicométrica.AbstracThis research designs a psychometric study of a new scoring system of the Bender Gestalt test modified to children: it is theQualitative Scoring System (Brannigan & Brunner, 2002, in a sample of 244 first grade children of primary level, in four public school of Lima. The approach aplied is the nonparametric item analysis using The test graft computer program (Ramsay, 1991. Our findings point to good levels of internal consistency, unidimensionality and good discriminative level ofthe categories of scoring from the Qualitative Scoring System. There are not demographic differences between gender or age.We discuss our findings within the context of the potential use of the Qualitative Scoring System and of the nonparametricitem analysis approach in the psychometric research.

  9. Assessment of the reliability in two groups of age, using the Qualitative Scoring System for the Bender Gestalt Test - Modified

    Directory of Open Access Journals (Sweden)

    César Ayax Merino Soto

    2011-01-01

    Full Text Available This study is looking for evidences of reliability, for the Qualification Qua- litative System (Brannigan y Brunner, 2002 applied to the Bender Gestalt Test – Modified. The participants were 86 children, divided in two groups: pre- school and school; and three students who scored the designs in both groups. The analysis was done in the final grade and the item. The results pointed to the good levels of results of external reliability and internal consistence in the pre- school group, while these levels were scored in the school group. These differences establish the relation between these two aspects of measurement error and the emphasis in an appropriate training of measurements that require the examiner’s judgments. We discussed our results considering the potential utility of this relative version of the Bender Gestalt Test for the clinical practice and investigation as well.

  10. 'Racial differences have to be considered': Lauretta Bender, Bellevue Hospital, and the African American psyche, 1936-52.

    Science.gov (United States)

    Doyle, Dennis

    2010-06-01

    This paper examines one US psychiatrist's engagement between 1936 and 1952 with a racialist strain of evolutionary thought. When Lauretta Bender began working with Bellevue Hospital's disproportionately black population, the psychiatric literature still circulated the crude evolutionary proposition that blacks remained stuck at a more primitive stage of development. In the 1930s, drawing insights from holistic, mechanistic and environmentalist thinking on the relationship between mind and body, Bender developed her own more circumspect racialist position. Although she largely abandoned her underdetermined version of racialism in the 1940s for an approach that left out race as an active factor of analysis, this paper contends that she probably never wrote off black primitivity as a theoretical possibility.

  11. Temperature: Human Regulating, Ants Conforming

    Science.gov (United States)

    Clopton, Joe R.

    2007-01-01

    Biological processes speed up as temperature rises. Procedures for demonstrating this with ants traveling on trails, and data gathered by students on the Argentine ant ("Linepithema humile") are presented. The concepts of temperature regulation and conformity are detailed with a focus on the processes rather than on terms that label the organisms.

  12. The metapleural gland of ants.

    Science.gov (United States)

    Yek, Sze Huei; Mueller, Ulrich G

    2011-11-01

    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 of the MG, sanitation and chemical defence, have received the strongest empirical support; two additional possible functions, recognition odour and territorial marking, are less well supported. The design of the MG is unusual for insects; glandular secretions are stored in a rigid, non-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 morphology, phylogenetic transitions and chemical ecology of the MGs of both the derived and the unstudied early-branching (basal) ant lineages is needed to elucidate the evolutionary origin and diversification of the MG of ants.

  13. Temperature: Human Regulating, Ants Conforming

    Science.gov (United States)

    Clopton, Joe R.

    2007-01-01

    Biological processes speed up as temperature rises. Procedures for demonstrating this with ants traveling on trails, and data gathered by students on the Argentine ant ("Linepithema humile") are presented. The concepts of temperature regulation and conformity are detailed with a focus on the processes rather than on terms that label the organisms.

  14. Test-retest reliability of the Advanced Psychodiagnostic Interpretation (API) scoring system for the Bender Gestalt in chronic schizophrenics.

    Science.gov (United States)

    Aucone, E J; Wagner, E E; Raphael, A J; Golden, C J; Espe-Pfeifer, P; Dornheim, L; Seldon, J; Pospisil, T; Proctor-Weber, Z; Calabria, M

    2001-09-01

    This study assesses the test-retest reliability of the revised Advanced Psychodiagnostic Interpretation (API) scoring system for the Bender Gestalt Test (BGT). The API system identifies 207 possible distortions in a BGT protocol. Test-retest reliability for 40 schizophrenic patients tested twice with a mean interval of 6.4 years (SD=3.8 years) was good, ranging from .71 to .80. Further reliability and validity studies are needed to further demonstrate the effectiveness of the system.

  15. Invasive ants of Bermuda revisited

    Directory of Open Access Journals (Sweden)

    James K. Wetterer

    2017-02-01

    Full Text Available For 60+ years, two of the world’s most widespread and destructive invasive ant species, the African big-headed ant (Pheidole megacephala from tropical Africa and the Argentine ant (Linepithema humile from subtropical South America, have been engaged in an epic battle on the islands of Bermuda. Both species are completely intolerant of the other and are also well-known for killing off native invertebrates, particularly other ants. Here I surveyed sites across Bermuda in 2016, including resurveys of the locations previously surveyed in 1963, 1966, 1973, 1986, and 2002, to provide an update on this conflict. The status of all other ant species present in the islands, including previous records from literature, is also provided. In addition, I surveyed ants nesting in red mangrove (Rhizophora mangle trees to evaluate whether this arboreal habitat may serve as a refuge for previously overlooked ant species. In 2016, L. humile occurred at most surveyed sites in Bermuda, including all ten resurveyed sites. Pheidole megacephala was present at only two resurveyed sites, a lower proportion of sites than any of the five earlier surveys. Still, P. megacephala occupied substantial areas, particularly in and around Hamilton, the capital of Bermuda. This survey increased the number of ant species with verified records from Bermuda to 25, including four exotic species recorded for the first time: Cardiocondyla minutior, Pheidole navigans, Strumigenys emmae, and Strumigenys membranifera. I found five ant species nesting in mangroves: L. humile plus four Old World exotics, C. minutior, Cardiocondyla obscurior, Monomorium floricola, and Plagiolepis alluaudi. It appears that L. humile may be better suited to the subtropical climate of Bermuda than P. megacephala, except perhaps in warmer and sunnier habitats, such as plantings along urban streets and in open parks, where P. megacephala may hold the advantage. The dataset on the new ant records from 2016 is

  16. Design and analysis of the internally cooled silicon mirrors and benders for wiggler sources at the Advanced Photon Source

    Energy Technology Data Exchange (ETDEWEB)

    Schildkamp, W.; Jaski, Y. [Consortium for Advanced Radiation Sources, University of Chicago, 5640 S. Ellis Ave., Chicago, IL 60637 (United States); Tonnessen, T.; Douglas, G. [Rocketdyne Albuquerque Operations, 2511 C. Broadbent Parkway, N.E., Albuquerque, NM 87107 (United States)

    1996-09-01

    When silicon single crystal mirrors are bent to cylindrical figures of typically 6 km bending radius, the moments needed are very small and easy to disturb by cooling attachments to the sides of the mirror. Hence, we decided to abandon the conventional concept of cooling plates attached to the sides of the mirrors and instead have chosen to use internal water channels. We present here the design of mirrors with cooling channels near the neutral axis of the silicon beam that have a rather thick {open_quote}{open_quote}hot wall.{close_quote}{close_quote} The results of this analytical work are nonintuitive, regarding the stresses produced by wiggler heating. The design path chosen minimizes figure errors due to coolant pressure variations and residual stresses from machining and bonding of multiple layers of silicon. The geometry of the water channels avoids water-to-vacuum seals and uses the mirror bender as the coolant manifold. Engineering efforts, which reduce the bending stresses at bender-to-silicon interface by a factor of five, will be presented. The complete mirror bender and motion control mechanics will be shown. {copyright} {ital 1996 American Institute of Physics.}

  17. Efeitos da compressão torácica manual versus a manobra de PEEP-ZEEP na complacência do sistema respiratório e na oxigenação de pacientes submetidos à ventilação mecânica invasiva Effects of manual rib-cage compression versus PEEP-ZEEP maneuver on respiratory system compliance and oxygenation in patients receiving mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Flavio Renato Antunes dos Santos

    2009-06-01

    Full Text Available OBJETIVOS: Os pacientes com incapacidade de desempenhar suas funções ventilatórias podem ser submetidos à ventilação mecânica invasiva. A fisioterapia respiratória atua no tratamento destes pacientes com a finalidade de melhorar sua função pulmonar. O objetivo do estudo foi avaliar os efeitos da compressão torácica manual versus a manobra de pressão expiratória final positiva-pressão expiratória final zero (PEEP-ZEEP na complacência do sistema respiratório e na oxigenação de pacientes em ventilação mecânica invasiva. MÉTODOS: Foi realizado um estudo bicêntrico, prospectivo, randomizado e crossover, incluindo pacientes em ventilação mecânica invasiva em modo controlado por um período superior a 48 horas. Os protocolos de fisioterapia respiratória foram realizados de forma aleatória, com intervalo de 24 horas entre eles. Dados da complacência do sistema respiratório e da oxigenação foram coletados antes da aplicação dos protocolos e 30 minutos após a aplicação dos mesmos. RESULTADOS: Doze pacientes completaram o estudo. Na análise intragrupo, em ambas as técnicas houve aumento estatisticamente significativo do volume corrente (p=0,002, da complacência estática (p=0,002 e complacência dinâmica (p=0,002. Com relação à oxigenação, no grupo compressão torácica manual, a saturação periférica de oxigênio aumentou com diferença significativa (p=0,011. CONCLUSÕES: A compressão torácica manual e a manobra de PEEP-ZEEP têm efeitos clínicos positivos e não diferem entre si. Em relação à oxigenação encontramos um comportamento favorável da saturação periférica de oxigênio no grupo compressão torácica manual.OBJECTIVES: Patients unable to perform breathing functions may be submitted to invasive mechanical ventilation. Chest physiotherapy acts directly on the treatment of these patients for the purpose of improving their lung function. The objective of this study was to evaluate the

  18. Uus töölpeinguseadus : nagu Soomes lama ajal? Ei, veel karmim / Maret Maripuu, Tarmo Kriis, Peep Peterson ; interv. Külli-Riin Tigasson

    Index Scriptorium Estoniae

    Maripuu, Maret, 1974-

    2008-01-01

    Uue töölepingu seaduse eelnõust. Vestlusringis on sotsiaalminister Maret Maripuu, Eesti tööandjate keskliidu juhataja Tarmo Kriis ja transpordi ametiühingu juhatuse esimees Peep Peterson. Lisatud: mida eelnõu muudab? ; ametiühingute keskliidu juhi Harri Taliga kommentaar: dzhungliseaduste tagasitulek? ; Helmes ASi nõukogu esimehe Jaan Pillesaare kommentaar: praegune seadus on tobe

  19. Uus töölpeinguseadus : nagu Soomes lama ajal? Ei, veel karmim / Maret Maripuu, Tarmo Kriis, Peep Peterson ; interv. Külli-Riin Tigasson

    Index Scriptorium Estoniae

    Maripuu, Maret, 1974-

    2008-01-01

    Uue töölepingu seaduse eelnõust. Vestlusringis on sotsiaalminister Maret Maripuu, Eesti tööandjate keskliidu juhataja Tarmo Kriis ja transpordi ametiühingu juhatuse esimees Peep Peterson. Lisatud: mida eelnõu muudab? ; ametiühingute keskliidu juhi Harri Taliga kommentaar: dzhungliseaduste tagasitulek? ; Helmes ASi nõukogu esimehe Jaan Pillesaare kommentaar: praegune seadus on tobe

  20. Hospitales seguros ante desastres

    Directory of Open Access Journals (Sweden)

    Celso Vladimir Bambaren Alatrista

    2007-07-01

    Full Text Available Entre 1982 a 2005 se registraron daños en 1 143 establecimientos de salud en el Perú, generalmente debido a sismos, lluvias e inundaciones. Los daños en los servicios de salud producen la interrupción de la atención de la población y de los programas de salud, así como generan un gran gasto para la rehabilitación y reconstrucción. Por ello, se requiere proteger a los establecimientos de salud y desarrollar una política de hospitales seguros ante desastres que incluya medidas para prevenir o reducción de la vulnerabilidad estructural, no estructural y funcional en los nuevos establecimientos y en los existentes.(Rev Med Hered 2007;18:149-154.

  1. FORMIDABEL: The Belgian Ants Database.

    Science.gov (United States)

    Brosens, Dimitri; Vankerkhoven, François; Ignace, David; Wegnez, Philippe; Noé, Nicolas; Heughebaert, André; Bortels, Jeannine; Dekoninck, Wouter

    2013-01-01

    FORMIDABEL is a database of Belgian Ants containing more than 27.000 occurrence records. These records originate from collections, field sampling and literature. The database gives information on 76 native and 9 introduced ant species found in Belgium. The collection records originated mainly from the ants collection in Royal Belgian Institute of Natural Sciences (RBINS), the 'Gaspar' Ants collection in Gembloux and the zoological collection of the University of Liège (ULG). The oldest occurrences date back from May 1866, the most recent refer to August 2012. FORMIDABEL is a work in progress and the database is updated twice a year. THE LATEST VERSION OF THE DATASET IS PUBLICLY AND FREELY ACCESSIBLE THROUGH THIS URL: http://ipt.biodiversity.be/resource.do?r=formidabel. The dataset is also retrievable via the GBIF data portal through this link: http://data.gbif.org/datasets/resource/14697 A dedicated geo-portal, developed by the Belgian Biodiversity Platform is accessible at: http://www.formicidae-atlas.be FORMIDABEL is a joint cooperation of the Flemish ants working group "Polyergus" (http://formicidae.be) and the Wallonian ants working group "FourmisWalBru" (http://fourmiswalbru.be). The original database was created in 2002 in the context of the preliminary red data book of Flemish Ants (Dekoninck et al. 2003). Later, in 2005, data from the Southern part of Belgium; Wallonia and Brussels were added. In 2012 this dataset was again updated for the creation of the first Belgian Ants Atlas (Figure 1) (Dekoninck et al. 2012). The main purpose of this atlas was to generate maps for all outdoor-living ant species in Belgium using an overlay of the standard Belgian ecoregions. By using this overlay for most species, we can discern a clear and often restricted distribution pattern in Belgium, mainly based on vegetation and soil types.

  2. 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...... are investigated. The influence of the evaporation factor in the pheromone update mechanism and the robustness of this parameter w.r.t. the runtime behavior have been determined for the example function OneMax.This work puts forward the rigorous runtime analysis of the 1-ANT on the example functions Leading......Ones and BinVal. With respect to Evolutionary Algorithms (EAs), such analyses were essential to develop methods for the analysis on more complicated problems. The proof techniques required for the 1-ANT, unfortunately, differ significantly from those for EAs, which means that a new reservoir of methods has...

  3. Monitoring of intratidal lung mechanics: a Graphical User Interface for a model-based decision support system for PEEP-titration in mechanical ventilation.

    Science.gov (United States)

    Buehler, S; Lozano-Zahonero, S; Schumann, S; Guttmann, J

    2014-12-01

    In mechanical ventilation, a careful setting of the ventilation parameters in accordance with the current individual state of the lung is crucial to minimize ventilator induced lung injury. Positive end-expiratory pressure (PEEP) has to be set to prevent collapse of the alveoli, however at the same time overdistension should be avoided. Classic approaches of analyzing static respiratory system mechanics fail in particular if lung injury already prevails. A new approach of analyzing dynamic respiratory system mechanics to set PEEP uses the intratidal, volume-dependent compliance which is believed to stay relatively constant during one breath only if neither atelectasis nor overdistension occurs. To test the success of this dynamic approach systematically at bedside or in an animal study, automation of the computing steps is necessary. A decision support system for optimizing PEEP in form of a Graphical User Interface (GUI) was targeted. Respiratory system mechanics were analyzed using the gliding SLICE method. The resulting shapes of the intratidal compliance-volume curve were classified into one of six categories, each associated with a PEEP-suggestion. The GUI should include a graphical representation of the results as well as a quality check to judge the reliability of the suggestion. The implementation of a user-friendly GUI was successfully realized. The agreement between modelled and measured pressure data [expressed as root-mean-square (RMS)] tested during the implementation phase with real respiratory data from two patient studies was below 0.2 mbar for data taken in volume controlled mode and below 0.4 mbar for data taken in pressure controlled mode except for two cases with RMS < 0.6 mbar. Visual inspections showed, that good and medium quality data could be reliably identified. The new GUI allows visualization of intratidal compliance-volume curves on a breath-by-breath basis. The automatic categorisation of curve shape into one of six shape

  4. 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...

  5. NOAA People Empowered Products (PeEP): Combining social media with scientific models to provide eye-witness confirmed products

    Science.gov (United States)

    Codrescu, S.; Green, J. C.; Redmon, R. J.; Minor, K.; Denig, W. F.; Kihn, E. A.

    2013-12-01

    NOAA products and alerts rely on combinations of models and data to provide the public with information regarding space and terrestrial weather phenomena and hazards. This operational paradigm, while effective, neglects an abundant free source of measurements: millions of eyewitnesses viewing weather events. We demonstrate the capabilities of a prototype People Empowered Product (PeEP) that combines the OVATION prime auroral model running at the NOAA National Geophysical Data Center with Twitter reports of observable aurora. We introduce an algorithm for scoring Tweets based on keywords to improve the signal to noise of this dynamic data source. We use the location of the aurora derived from this new database of crowd sourced observations to validate the OVATION model for use in auroral forecasting. The combined product displays the model aurora in real time with markers showing the location and text of tweets from people actually observing the aurora. We discuss how the application might be extended to other space weather products such as radiation related satellite anomalies.

  6. Pest repellent properties of ant pheromones

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2012-01-01

    Many ant species are efficient control agents against a wide range of pest insects in many crops. They control pest insects via predation; however, ant communication is based on chemical cues which may be eavesdropped by potential prey and serve as chemical warning signals. Thus, the presence...... 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....

  7. ANT, tourism and situated globality

    DEFF Research Database (Denmark)

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

    2015-01-01

    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......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...... 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...

  8. Correlation of liquefaction resistance with shear wave velocity based on laboratory study using bender element

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yan-guo; CHEN Yun-min; KE Han

    2005-01-01

    Recent studies using field case history data yielded new criteria for evaluating liquefaction potential in saturated granular deposits based on in situ, stress-corrected shear wave velocity. However, the conditions of relatively insufficient case histories and limited site conditions in this approach call for additional data to more reliably define liquefaction resistance as a function of shear wave velocity. In this study, a series of undrained cyclic triaxial tests were conducted on saturated sand with shear wave velocity Vs measured by bender element. By normalizing the data with respect to minimum void ratio, the test results, incorporated with previously published laboratory data, statistically revealed good correlation of cyclic shear strength with small-strain shear modulus for sandy soils, which is almost irrespective of soil types and confining pressures. The consequently determined cyclic resistance ratio, CRR, was found to be approximately proportional to Vs4. Liquefaction resistance boundary curves were established by applying this relationship and compared to liquefaction criteria derived from seismic field measurements. Although in the range of Vs1>200 m/s the presented curves are moderately conservative, they are remarkably consistent with the published field performance criteria on the whole.

  9. Comparison of the Minnesota Percepto-Diagnostic Test and Bender-Gestalt: relationship with achievement criteria.

    Science.gov (United States)

    Fuller, G B; Wallbrown, F H

    1983-11-01

    Administered the Bender-Gestalt (BG) and Minnesota Percepto-Diagnostic Test (MPD) to 69 first-grade children prior to administration of the California Achievement Test (CAT). Order of administration for the BG and MPD was counterbalanced to control for practice effects. Correlations (rs) were computed between the 9 CAT subtests and scores from the BG and MPD. The DD score from the MPD correlated significantly with all 9 CAT subtests. The SpCD score from the MPD correlated significantly with 6 of the 9 CAT subtests. The BG Koppitz score correlated significantly with 6 of the 9 CAT subtests. Both the DD and SpCD scores showed a significantly higher negative r with Reading Vocabulary, Total Reading, and Arithmetic Computation than the BG. Furthermore, both types of MPD scores showed a much higher average r with the 9 CAT subtests than was evident for the BG. These findings suggest that DD and SpCD scores from the MPD provide a more sensitive measure of deficits in visual-motor perception than the Koppitz score from the BG.

  10. Thomas Bender. Historia de los Estados Unidos: una nación entre naciones

    Directory of Open Access Journals (Sweden)

    Jhon Florián Guzmán

    2012-01-01

    Full Text Available El libro de Thomas Bender es una obra que busca reclamar un lugar dentro de la extensa bibliografía que ya acumula la historia de los Estados Unidos. Para ello, apunta al reconocimiento de las conexiones externas de la historia nacional y, de paso, entiende que la nación no es una entidad autosustentada. Está, al igual que cualquier forma de solidaridad humana, conectada con aquello que la excede, y que además, contribuye a configurarla. Es por esta razón que el autor debate con los teóricos del excepcionalismo norteamericano, para instalar los principales acontecimientos nacionales, incluidos los más distintivos (como la revolución y la guerra civil, en un contexto global. El debate sobre el método, más que el barrido detallado de los hechos históricos, es el principal aporte de este historiador del Centro Internacional para Estudios Avanzados de la Universidad de Nueva York.

  11. Benders decomposition for discrete material optimization in laminate design with local failure criteria

    DEFF Research Database (Denmark)

    Munoz, Eduardo; Stolpe, Mathias; Bendsøe, Martin P.

    2009-01-01

    We study the problem of designing a minimum compliance (or weight) composite laminate. The optimization is made by selecting, out of a set of candidate materials, the materials that will be used in the building process of a laminated structure. The material candidate set is given as data of the d......We study the problem of designing a minimum compliance (or weight) composite laminate. The optimization is made by selecting, out of a set of candidate materials, the materials that will be used in the building process of a laminated structure. The material candidate set is given as data...... a generalized Benders Decomposition technique, a global optimization technique for mixed-integer optimization. The method, under certain conditions, solves optimization problems to global optimum and allows us to solve larger problems. The technique solves the optimization problem iteratively, where at each...... iteration, a local linear approximation of the objective function and the feasible set are included in a mixed integer linear program, called the relaxed master problem. The approximations are obtained by solving one analysis problem and one adjoint problem. The process continues, until the optimal value...

  12. 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

  13. Eestlastest Austraalias / Peep Pillak ; foto: Peep Pillak

    Index Scriptorium Estoniae

    Pillak, Peep

    2009-01-01

    eestlaste saabumisest Austraaliasse XVII saj. lõpus, XIX ja XX sajandil, Sydney Eesti Majast, pagulaste saabumisest pärast II maailmasõda, Sydney Jaani kogudusest, eestlaste kalmistust Rookwoodis, ajaleht "Meie Kodu" asutamisest, Eesti konsulaadist Sydneys, Eesti Arhiivist Austraalias, eestlastest Thirlmeres ja mujal, seltsielust, kirjasõna Austraalia eestlastest

  14. A solution approach based on Benders decomposition for the preventive maintenance scheduling problem of a stochastic large-scale energy system

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Muller, Laurent Flindt; Petersen, Bjørn

    2013-01-01

    This paper describes a Benders decomposition-based framework for solving the large scale energy management problem that was posed for the ROADEF 2010 challenge. The problem was taken from the power industry and entailed scheduling the outage dates for a set of nuclear power plants, which need...... to be regularly taken down for refueling and maintenance, in such away that the expected cost of meeting the power demand in a number of potential scenarios is minimized. We show that the problem structure naturally lends itself to Benders decomposition; however, not all constraints can be included in the mixed...... integer programming model. We present a two phase approach that first uses Benders decomposition to solve the linear programming relaxation of a relaxed version of the problem. In the second phase, integer solutions are enumerated and a procedure is applied to make them satisfy constraints not included...

  15. Identifying potential evolutionary relationships within a facultative lycaenid-ant system: Ant association,oviposition, and butterfly-ant conflict

    Institute of Scientific and Technical Information of China (English)

    NEIL COLLIER

    2007-01-01

    Facultative associations are commonly encountered between ants and lycaenids,although the nature and patterns of associations are typically unclear. This study investigated a facultative symbiosis involving the lycaenid Theclinesthes albocincta (Lycaenidae), its host plant Adriana quadripartita and Australian native ants. Ants in the genera Ochetellus and Iridomyrmex were most frequently found in association with T. albocincta larvae,although Iridomyrmex ants were found in much lower abundance than were ants in Ochetellus. The abundances of Ochetellus and Iridomyrmex were highly correlated with larval abundance, but not egg abundance. Observations and experiments recorded oviposition on male inflorescences on more than 95% of occasions, but oviposition was not greater on inflorescences with ants present. Behavioral assays showed that Iridomyrmex ants were aggressive towards female butterflies on significantly more occasions than were Ochetellus ants. These findings indicate potential evolutionary relationships between T. albocincta and two genera of ants that were abundant within the habitat.

  16. 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.

  17. Monoculture of leafcutter ant gardens.

    Directory of Open Access Journals (Sweden)

    Ulrich G Mueller

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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.

  18. Discriminación de la ansiedad a través del Test Gestáltico Bender

    OpenAIRE

    Alonso Martín, Pilar; Juídias Barroso , Jerónimo

    2008-01-01

    Generalmente la familia y los profesionales de la enseñanza entienden la importancia de la prevención, pero sólo se ocupan de los problemas emocionales cuando empiezan a aparecer la sintomatología y el niño manifiesta síntomas del conflicto. Es importante un buen diagnóstico de dichos trastornos emocionales, por eso este trabajo pretende determinar si el Test de L. Bender podría ser utilizado como discriminador de ansiedad infantil. La muestra está compuesta por 722 sujetos de ...

  19. Design, construction and tests of a crystal bender which provides constant position of the central part of the crystal

    CERN Document Server

    Artemiev, A I; Busetto, E; Franc, F; Hrdy, J; Mrazek, D; Savoia, A

    2001-01-01

    We propose a new scheme for a crystal bender. This scheme provides the constant position of the central point of a rectangular crystal during the bending process. The measurements show that the full scatter of the position of the central part of a sample during the bending process is slightly less than 100 microns. The measured profile of a sample bent to a radius of about 50 cm was compared with a circle fitted by the least square method. The relative difference between measured and fitted radii appeared to be about 10 sup - sup 5.

  20. Macroevolutionary assembly of ant/plant symbioses: Pseudomyrmex ants and their ant-housing plants in the Neotropics.

    Science.gov (United States)

    Chomicki, Guillaume; Ward, Philip S; Renner, Susanne S

    2015-11-22

    Symbioses include some of the clearest cases of coevolution, but their origin, loss or reassembly with different partners can rarely be inferred. Here we use ant/plant symbioses involving three plant clades to investigate the evolution of symbioses. We generated phylogenies for the big-eyed arboreal ants (Pseudomyrmecinae), including 72% of their 286 species, as well as for five of their plant host groups, in each case sampling more than 61% of the species. We show that the ant-housing Vachellia (Mimosoideae) clade and its ants co-diversified for the past 5 Ma, with some species additionally colonized by younger plant-nesting ant species, some parasitic. An apparent co-radiation of ants and Tachigali (Caesalpinioideae) was followed by waves of colonization by the same ant clade, and subsequent occupation by a younger ant group. Wide crown and stem age differences between the ant-housing genus Triplaris (Polygonaceae) and its obligate ant inhabitants, and stochastic trait mapping, indicate that its domatium evolved earlier than the ants now occupying it, suggesting previous symbioses that dissolved. Parasitic ant species evolved from generalists, not from mutualists, and are younger than the mutualistic systems they parasitize. Our study illuminates the macroevolutionary assembly of ant/plant symbioses, which has been highly dynamic, even in very specialized systems. © 2015 The Author(s).

  1. 基于Bender's分解和内点法的无功优化规划%OPTIMAL REACTIVE POWER PLANNING USING BENDER'S DECOMPOSITION TECHNIQUE AND INTERIOR POINT METHOD

    Institute of Scientific and Technical Information of China (English)

    王成山; 张义

    2003-01-01

    对于目标为网损费用和无功设备投资费用最小的无功优化规划问题,Bender's分解技术是一种有效的解决方法.原-对偶仿射尺度法作为一种被证明具有多项式时间复杂性的方法,已经被用于无功优化的计算中.本文结合Bender's分解技术和原-对偶仿射尺度法,解决了城市高中压配电网的长期无功优化规划问题.通过实际电力系统的计算结果表明,此算法的迭代收敛次数稳定,优化结果的经济效益明显,适合于大规模电力系统的无功优化规划计算.

  2. EXPLORACIÓN DE DIFERENCIAS NORMATIVAS EN EL SISTEMA DE CALIFICACIÓN CUALITATIVA PARA EL TEST GESTÁLTICO DE BENDER MODIFICADO/ EXPLORING NORMATIVE DIFFERENCES IN QUALITATIVE SCORING SYSTEM FOR MODIFIED THE BENDER GESTALT TEST

    Directory of Open Access Journals (Sweden)

    César Merino Soto*

    2011-09-01

    Full Text Available RESUMENEl presente estudio explora la magnitud de las diferencias en los puntajes del Sistema de Calificación Cualitativa parael Test Gestáltico de Bender Modificado, usando diferente información normativa proveniente de Perú, Estados Unidos yChina. En una muestra de 324 niños(as peruanos entre 5 y 6 años de edad, se analizaron las potenciales diferencias en ladensidad, tendencia central, dispersión y clasificaciones de rendimiento visomotor. Se hallaron grandes diferenciasnormativas, y por lo tanto, el desempeño en los participantes se vio altamente sobreestimado o subestimado dependiendode la norma usada. Se discute el impacto de estos resultados en la apropiada práctica evaluativa en niños.ABSTRACTThis study explores the magnitude of difference in scores from Qualitative Scoring System to Bender Gestalt TestModified using different normative data from Peru, USA and China. In a sample of 324 children (boys and girls between5 and 6 ages, we analyzed the potential differences in density, central tendency, dispersion and visual motor performanceclassifications. It was found large normative differences, and therefore, performance in participants was highlyoverestimated or underestimated depending on the standard used. It discusses the impact of these results in the appropriateassessment practice in children.

  3. 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...... of the MG, sanitation and chemical defence, have received the strongest empirical support; two additional possible functions, recognition odour and territorial marking, are less well supported. The design of the MG is unusual for insects; glandular secretions are stored in a rigid, non...... morphology, phylogenetic transitions and chemical ecology of the MGs of both the derived and the unstudied early-branching (basal) ant lineages is needed to elucidate the evolutionary origin and diversification of the MG of ants....

  4. Ants medicate to fight disease.

    Science.gov (United States)

    Bos, Nick; Sundström, Liselotte; Fuchs, Siiri; Freitak, Dalial

    2015-11-01

    Parasites are ubiquitous, and the ability to defend against these is of paramount importance. One way to fight diseases is self-medication, which occurs when an organism consumes biologically active compounds to clear, inhibit, or alleviate disease symptoms. Here, we show for the first time that ants selectively consume harmful substances (reactive oxygen species, ROS) upon exposure to a fungal pathogen, yet avoid these in the absence of infection. This increased intake of ROS, while harmful to healthy ants, leads to higher survival of exposed ants. The fact that ingestion of this substance carries a fitness cost in the absence of pathogens rules out compensatory diet choice as the mechanism, and provides evidence that social insects medicate themselves against fungal infection, using a substance that carries a fitness cost to uninfected individuals.

  5. A cellular automata model for ant trails

    Indian Academy of Sciences (India)

    Sibel Gokce; Ozhan Kayacan

    2013-05-01

    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 (i) ant colony consists of two kinds of ants, goodand poor-smelling ants, (ii) ants might make U-turn for some special reasons. For some values of densities of good- and poor-smelling ants, the flux and mean velocity of the colony were studied as a function of density and evaporation rate of pheromone.

  6. Compared study on the effects of mechanical controled ventilation (MCV with or without the use of positive-end-expiratory-pressure (PEEP on inter-pleural pressure variation in horse anesthesia

    Directory of Open Access Journals (Sweden)

    Melaine Klemm

    1998-01-01

    Full Text Available Uma das principais causas de mortalidade em anestesia eqüina é a grave hipoxemia, conseqüência da formação de "shunt" intrapulmonar. Em seres humanos, a hipóxia é tratada com uso de pressão positiva no final da expiração (PEEP, que, nesta espécie, previne o fechamento de vias aéreas, aumenta a capacidade residual funcional e melhora a oxigenação arterial. Estudamos os efeitos de PEEP sobre a variação do deltaPpl e sua repercussão no sistema cardiovascular, comparando ventilação espontânea (VE, à ventilação mecânica controlada (VMC sem PEEP e com PEEP de 10 cm H2O. Foram utilizados 12 animais adultos de ambos os sexos que foram submetidos a anestesia geral em ventilação espontânea, VMC sem e com PEEP. A técnica anestésica foi padronizada para todos os indivíduos. Os parâmetros hemodinâmicos, ventilatórios e de oxigenação foram mensurados no decorrer do experimento. A análise estatística dos resultados demostra que: não houve queda significativa da PAM entre os diferentes tipos de ventilação, nem alteração significativa das freqüências respiratória e cardíaca, pH, HCO3, BE e SatHb entre os três tipos de ventilação. Notou-se aumento da PaO2 entre VE e VMC paralelo a um aumento constante da PaCO2. Não foram verificadas reduções significativas do gradiente alvéolo-arterial, "shunt" e conteúdo de oxigênio. Durante a VCM e VCM com PEEP, observaram-se os valores mais baixos de "shunt". Houve alterações significativas do deltaPpl, que diminuiu durante a VMC e VMC com PEEP. Concluímos que a VMC e VMC com PEEP de 10 cm H2O não são deletérios ao sistema cardiopulmonar.

  7. Scenario-based modeling for multiple allocation hub location problem under disruption risk: multiple cuts Benders decomposition approach

    Science.gov (United States)

    Yahyaei, Mohsen; Bashiri, Mahdi

    2017-03-01

    The hub location problem arises in a variety of domains such as transportation and telecommunication systems. In many real-world situations, hub facilities are subject to disruption. This paper deals with the multiple allocation hub location problem in the presence of facilities failure. To model the problem, a two-stage stochastic formulation is developed. In the proposed model, the number of scenarios grows exponentially with the number of facilities. To alleviate this issue, two approaches are applied simultaneously. The first approach is to apply sample average approximation to approximate the two stochastic problem via sampling. Then, by applying the multiple cuts Benders decomposition approach, computational performance is enhanced. Numerical studies show the effective performance of the SAA in terms of optimality gap for small problem instances with numerous scenarios. Moreover, performance of multi-cut Benders decomposition is assessed through comparison with the classic version and the computational results reveal the superiority of the multi-cut approach regarding the computational time and number of iterations.

  8. Ant opsins: sequences from the Saharan silver ant and the carpenter ant.

    Science.gov (United States)

    Popp, M P; Grisshammer, R; Hargrave, P A; Smith, W C

    1996-03-01

    cDNA clones encoding opsins from compound eyes of carpenter ant, Camponotus abdominalis, and Saharan silver ant, Cataglyphis bombycina, were isolated from cDNA libraries. The opsin cDNAs from each species code for deduced proteins with 378 amino acids which are 92% identical. Of the 30 amino acid differences between the two proteins, 13 are non-conservative. Eight of these non-conservative substitutions are within the membrane spanning domain. The presence of a potential Schiff-base counterion in helix III in both species suggests that these opsins are the protein moiety of the visible range pigments. When compared to all known opsins, these opsins are most similar to the opsin from preying mantis (76% identity at the amino acid level). Phyletic comparisons group the two ant opsins with the other arthropod long wavelength opsins.

  9. Comparison of the Bender Gestalt-II and VMI-V in Samples of Typical Children and Children with High-Functioning Autism Spectrum Disorders

    Science.gov (United States)

    Volker, Martin A.; Lopata, Christopher; Vujnovic, Rebecca K.; Smerbeck, Audrey M.; Toomey, Jennifer A.; Rodgers, Jonathan D.; Schiavo, Audrey; Thomeer, Marcus L.

    2010-01-01

    The visual-motor skills of 60 children with high-functioning autism spectrum disorders (HFASDs) and 46 typically developing children were assessed using the Bender Visual-Motor Gestalt Test-Second Edition (BG-II) and Beery-Buktenica Developmental Test of Visual-Motor Integration, Fifth Edition (VMI-V). Within-group comparisons yielded substantive…

  10. A Review of the Non-Motoric Visual Gestalt Test and a Comparison with the Bender Visual-Motor Gestalt Test.

    Science.gov (United States)

    Elovitz, Gerald P.

    1979-01-01

    Measures of visual perception, such as the Bender Visual-Motor Gestalt Test (BVMGT) usually require motoric responding, i.e., drawing of figures. An alternative test, the Non-Motoric Visual Gestalt Test (NVGT), is compared with the BVMGT and shown to be superior in measuring visual-perceptual abilities that can discriminate poor and average…

  11. Comparison of Learning Disabled Children's Performance on Bender Visual-Motor Gestalt Test and Beery's Developmental Test of Visual Motor Integration.

    Science.gov (United States)

    Skeen, Judith A.; And Others

    1982-01-01

    A comparison was made of the performance of 30 learning-disabled students on the Bender Visual-Motor Gestalt Test and the Beery Developmental Test of Visual Motor Integration. A significant correlation of -.72 was obtained. No significant difference was found in estimations of age equivalents. (Author)

  12. Comparison of the Bender Gestalt-II and VMI-V in Samples of Typical Children and Children with High-Functioning Autism Spectrum Disorders

    Science.gov (United States)

    Volker, Martin A.; Lopata, Christopher; Vujnovic, Rebecca K.; Smerbeck, Audrey M.; Toomey, Jennifer A.; Rodgers, Jonathan D.; Schiavo, Audrey; Thomeer, Marcus L.

    2010-01-01

    The visual-motor skills of 60 children with high-functioning autism spectrum disorders (HFASDs) and 46 typically developing children were assessed using the Bender Visual-Motor Gestalt Test-Second Edition (BG-II) and Beery-Buktenica Developmental Test of Visual-Motor Integration, Fifth Edition (VMI-V). Within-group comparisons yielded substantive…

  13. Bender Gestalt Recall as a measure of short-term visual memory in children and adolescents with psychotic and other severe disorders.

    Science.gov (United States)

    McCarthy, James; Rabinowitz, Dena; Habib, Mandy; Goldman, Heather; Miley, Diana; Stefanyshyn, Hanna Yim; Freeman, Shuamis; Murray, Tracey; Clauselle, Renee

    2002-12-01

    To investigate the short-term visual memory ability of children and adolescents with severe psychiatric disorders, 82 child and adolescent inpatients and day hospital patients in a state psychiatric hospital were administered the Bender Gestalt Test as part of a psychological assessment and then asked to reproduce the designs from memory. No significant differences were found between groups on either the Bender Gestalt Recall, or the WISC-III IQs and the Digit Span and Symbol Search subtests for Psychotic Disorders (Schizophrenia, Schizoaffective Disorder, Psychosis Not Otherwise Specified), Attention Deficit Hyperactivity Disorder, Mood Disorders or Mood Disorders with co-morbid Attention Deficit Hyperactivity Disorder. The Coding subtest scores of the Psychotic Disorders group were significantly lower than the ADHD group. Analyses showed that the Bender Gestalt Recall was significantly related to age. Performance IQ, and sex. The results were discussed in terms of both the poor cognitive functioning of children and adolescents with persistent, severe mental illness, and the importance of developmental level when using the Bender Gestalt Recall as a rough measure of short-term visual memory.

  14. Pest repellent properties of ant pheromones

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2012-01-01

    ant species (iii) Azteca instabilis and (iv) Camponotus textor reduce herbivory by flea beetles (Margaridisa sp.), whereas (v) deposits from Solenopsis geminata, did not lead to reduced herbivory. Further evidence for the impact of ant pheromones comes from studies showing that non-herbivorous ant...

  15. Ant colony optimization in continuous problem

    Institute of Scientific and Technical Information of China (English)

    YU Ling; LIU Kang; LI Kaishi

    2007-01-01

    Based on the analysis of the basic ant colony optimization and optimum problem in a continuous space,an ant colony optimization (ACO) for continuous problem is constructed and discussed. The algorithm is efficient and beneficial to the study of the ant colony optimization in a continuous space.

  16. Using Ants to Investigate the Environment

    Science.gov (United States)

    Hagevik, Rita A.

    2005-01-01

    The best place for students to begin to understand complex environmental relationships is in their own back yards. Doing investigations of ants allows students to establish a baseline survey of ant fauna, test the importance of ants in nutrient cycling and soil structure maintenance, and increase their understanding of the environment and their…

  17. Male parentage in army ants

    DEFF Research Database (Denmark)

    Kronauer, Daniel J C; Schöning, Caspar; Boomsma, Jacobus J

    2006-01-01

    of active research in insect sociobiology. Here we present microsatellite data for 176 males from eight colonies of the African army ant Dorylus (Anomma) molestus. Comparison with worker genotypes and inferred queen genotypes from the same colonies show that workers do not or at best very rarely reproduce...

  18. Optimal cue integration in ants.

    Science.gov (United States)

    Wystrach, Antoine; Mangan, Michael; Webb, Barbara

    2015-10-07

    In situations with redundant or competing sensory information, humans have been shown to perform cue integration, weighting different cues according to their certainty in a quantifiably optimal manner. Ants have been shown to merge the directional information available from their path integration (PI) and visual memory, but as yet it is not clear that they do so in a way that reflects the relative certainty of the cues. In this study, we manipulate the variance of the PI home vector by allowing ants (Cataglyphis velox) to run different distances and testing their directional choice when the PI vector direction is put in competition with visual memory. Ants show progressively stronger weighting of their PI direction as PI length increases. The weighting is quantitatively predicted by modelling the expected directional variance of home vectors of different lengths and assuming optimal cue integration. However, a subsequent experiment suggests ants may not actually compute an internal estimate of the PI certainty, but are using the PI home vector length as a proxy. © 2015 The Author(s).

  19. The antipredatory behaviours of Neotropical ants towards army ant raids (Hymenoptera : Formicidae)

    OpenAIRE

    Dejean, A.; Corbara, B.; Roux, Olivier; Orivel, J.

    2014-01-01

    Group hunting, nomadism, wingless queens and colony fission characterize army ants, allowing them to have become the main tropical arthropod predators, mostly of other social insects. We studied the reactions of different ant species to the New World army ants Eciton burchellii (WESTWOOD, 1842) and E. hamatum (FABRICUS, 1782) (Ecitoninae). We compiled our results with those already known in a synthetic appendix. A wide range of ant species react to the approach of army ant raids by evacuating...

  20. Effects of manual rib-cage compression versus PEEP-ZEEP maneuver on respiratory system compliance and oxygenation in patients receiving mechanical ventilation.

    Science.gov (United States)

    Santos, Flavio Renato Antunes Dos; Schneider Júnior, Luiz Carlos; Forgiarini Junior, Luiz Alberto; Veronezi, Jefferson

    2009-06-01

    Patients unable to perform breathing functions may be submitted to invasive mechanical ventilation. Chest physiotherapy acts directly on the treatment of these patients for the purpose of improving their lung function. The objective of this study was to evaluate the effects of manual rib-cage compression versus the positive end expiratory pressure-zero end expiratory pressure (PEEP-ZEEP) maneuver, on compliance of the respiratory system and oxygenation in patients under invasive mechanical ventilation. A double centric, prospective, randomized and crossover study, with patients under invasive mechanical ventilation, in controlled mode for more than 48 hours was carried out. The protocols of chest physiothe-rapy were randomly applied at an interval of 24 hours. Data of respiratory system compliance and oxygenation were collected before application of the protocols and 30 minutes after. Twelve patients completed the study. Intragroup analysis, for both techniques showed a statistically significant difference in tidal volume (p=0.002), static compliance (p=0.002) and dynamic compliance (p=0.002). In relation to oxygenation, in the group of manual rib-cage compression, peripheral oxygen saturation increased with a significant difference (p=0.011). Manual rib-cage compression and PEEP-ZEEP maneuver have positive clinical effects. In relation to oxygenation we found a favorable behavior of peripheral oxygen saturation in the group of manual rib-cage compression.

  1. Thomas Bender. Historia de los Estados Unidos: una nación entre naciones

    Directory of Open Access Journals (Sweden)

    Jhon Florián Guzmán

    2012-06-01

    Full Text Available Normal 0 21 false false false ES-CO X-NONE X-NONE MicrosoftInternetExplorer4 El libro de Thomas Bender es una obra que busca reclamar un lugar dentro de la extensa bibliografía que ya acumula la historia de los Estados Unidos. Para ello, apunta al reconocimiento de las conexiones externas de la historia nacional y, de paso, entiende que la nación no es una entidad autosustentada. Está, al igual que cualquier forma de solidaridad humana, conectada con aquello que la excede, y que además, contribuye a configurarla. Es por esta razón que el autor debate con los teóricos del excepcionalismo norteamericano, para instalar los principales acontecimientos nacionales, incluidos los más distintivos (como la revolución y la guerra civil, en un contexto global. El debate sobre el método, más que el barrido detallado de los hechos históricos, es el principal aporte de este historiador del Centro Internacional para Estudios Avanzados de la Universidad de Nueva York. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  2. Evolutional Ant Colony Method Using PSO

    Science.gov (United States)

    Morii, Nobuto; Aiyoshi, Eitarou

    The ant colony method is one of heuristic methods capable of solving the traveling salesman problem (TSP), in which a good tour is generated by the artificial ant's probabilistic behavior. However, the generated tour length depends on the parameter describing the ant's behavior, and the best parameters corresponding to the problem to be solved is unknown. In this technical note, the evolutional strategy is presented to find the best parameter of the ant colony by using Particle Swarm Optimization (PSO) in the parameter space. Numerical simulations for benchmarks demonstrate effectiveness of the evolutional ant colony method.

  3. Microsatellite primers for fungus-growing ants

    DEFF Research Database (Denmark)

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

    2002-01-01

    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.......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...

  4. Microsatellite Primers for Fungus-Growing Ants

    DEFF Research Database (Denmark)

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

    2002-01-01

    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.......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...

  5. 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....

  6. 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....

  7. Efeito da posição prona sem PEEP na oxigenação e complacência em modelo experimental com lesão pulmonar Effect of prone position without PEEP on oxygenation and complacency in an experimental model of lung injury

    Directory of Open Access Journals (Sweden)

    Ana Cristina Z. Yagui

    2007-08-01

    Full Text Available OBJETIVO: Observar os efeitos da posição prona e a necessidade da pressão expiratória positiva final (PEEP na melhora da oxigenação. MÉTODOS: Dezesseis ratos foram anestesiados e ventilados com volume corrente de 8 mL/kg, freqüência respiratória de 60 rpm e PEEP = 0 cmH2O (ZEEP, em posição supina por 30 minutos. Após, foi induzida a lesão pulmonar através da instilação intratraqueal de ácido clorídrico. Quando estabelecida a lesão, os ratos foram pronados por mais 30 minutos e randomizados em dois grupos: grupo 1: associou-se PEEP = 5 cmH2O; grupo 2: manteve-se ZEEP. Medidas de mecânica pulmonar, da gasometria arterial e de pressão arterial média foram coletadas ao final de cada fase. RESULTADOS: A pressão parcial de oxigênio do grupo 1 aumentou significativamente de 98,7±26,5 para 173,9±58,4 mmHg entre as fases lesão e prona; o grupo 2 não se alterou, variando de 99,6±15,4 para 100,5±24,5 mmHg. Quanto à complacência, o grupo 1 também apresentou melhora significativa, de 0,20±0,01 para 0,23±0,02 mL/cmH2O, ao passo que o grupo 2 mais uma vez não apresentou melhora, de 0,21±0,02 para 0,22±0,01 mL/cmH2O. A medida da pressão arterial média não apresentou alterações significativas em ambos os grupos durante todo o experimento. CONCLUSÕES: A posição prona somente apresentou melhora da oxigenação e mecânica respiratória quando associada à PEEP = 5 cmH2O. A posição prona com e sem PEEP = 5 cmH2O não trouxe prejuízos hemodinâmicos.OBJECTIVE: To observe the effects of the prone position and the need for positive end-expiratory pressure (PEEP to improve oxygenation. METHODS: Sixteen rats were anesthetized and ventilated at a tidal volume of 8 mL/kg, respiratory rate of 60 rpm and PEEP = 0 cmH2O (ZEEP, in the supine position for 30 minutes. Lung injury was then induced by means of intratracheal instillation of hydrochloric acid. Once the injury was established, rats were placed in the prone position

  8. Evidences of validity of bender – gradual scoring system (B-SPG / Evidências de validade do bender – sistema de pontuação gradual (B-SPG

    Directory of Open Access Journals (Sweden)

    Ana Paula Porto Noronha

    2005-01-01

    Full Text Available This study aimed to gather evidences of validity for the Bender test – Gradual Scoring System (B-SPG, investigating developmental changes based on the relationships between its scores and the ages of the children. The study investigated 1052 children attending from pre-school to fourth grade of eight municipal and state public schools of Campinas (a city in the state of São Paulo, Brazil and the surrounding region. Ages ranged from six to ten years old, with an average of 8,35. The findings indicated that according to the increase of age, the B-SPG scores diminished, suggesting that the distortions progressively diminish as the children become older. Although other studies are suggested, the results presented here are consonant with researches that sought to establish that it is possible too find a maturational character among the figures of the test.

  9. Muusika : Virtuoosid taas tulemas. Tüüri muusika balletiks. Kaljuste Norras ja Belgias. Neeme Järvi viib Peterburi "Joonase lähetamise". Peep Lassmann jätkab rektorina. Eesti heliloojate kogumikplaat

    Index Scriptorium Estoniae

    2002-01-01

    Vladimir Spivakov ja Moskva Virtuoosid esinevad Tallinnas Estonia kontserdisaalis 15. IV. Tüüri muusikat kasutatakse Heinz Spoerli balletis "...der Sonne leuchten ist ihr Kleid". Tõnu Kaljuste tegemistest Norras ja Belgias. Neeme Järvi viib Peterburi "Joonase lähetamise". Peep Lassmann jätkab rektorina kuni aastani 2007.Eesti Raadio esitles eesti heliloomingu kogumik plaate. "Klassikaraadio" sai seitsmeaastaseks

  10. Introduced fire ants can exclude native ants from critical mutualist-provided resources.

    Science.gov (United States)

    Wilder, Shawn M; Barnum, Thomas R; Holway, David A; Suarez, Andrew V; Eubanks, Micky D

    2013-05-01

    Animals frequently experience resource imbalances in nature. For ants, one resource that may be particularly valuable for both introduced and native species is high-carbohydrate honeydew from hemipteran mutualists. We conducted field and laboratory experiments: (1) to test if red imported fire ants (Solenopsis invicta) competed with native ants for access to mutualisms with aphids, and (2) to quantify the effects of aphid honeydew presence or absence on colony growth of native ants. We focused on native dolichoderine ants (Formicidae, Dolichoderinae) because they are abundant ants that have omnivorous diets that frequently include mutualist-provided carbohydrates. At two sites in the southeastern US, native dolichoderine ants were far less frequent, and fire ants more frequent, at carbohydrate baits than would be expected based on their frequency in pitfall traps. A field experiment confirmed that a native ant species, Dorymyrmex bureni, was only found tending aphids when populations of S. invicta were suppressed. In the laboratory, colonies of native dolichoderine ants with access to both honeydew and insect prey had twice as many workers and over twice as much brood compared to colonies fed only ad libitum insect prey. Our results provide the first experimental evidence that introduced ants compete for access to mutualist-provided carbohydrates with native ants and that these carbohydrates represent critical resources for both introduced and native ants. These results challenge traditional paradigms of arthropod and ant nutrition and contribute to growing evidence of the importance of nutrition in mediating ecological interactions.

  11. Team swimming in ant spermatozoa.

    Science.gov (United States)

    Pearcy, Morgan; Delescaille, Noémie; Lybaert, Pascale; Aron, Serge

    2014-06-01

    In species where females mate promiscuously, competition between ejaculates from different males to fertilize the ova is an important selective force shaping many aspects of male reproductive traits, such as sperm number, sperm length and sperm-sperm interactions. In eusocial Hymenoptera (bees, wasps and ants), males die shortly after mating and their reproductive success is ultimately limited by the amount of sperm stored in the queen's spermatheca. Multiple mating by queens is expected to impose intense selective pressure on males to optimize the transfer of sperm to the storage organ. Here, we report a remarkable case of cooperation between spermatozoa in the desert ant Cataglyphis savignyi. Males ejaculate bundles of 50-100 spermatozoa. Sperm bundles swim on average 51% faster than solitary sperm cells. Team swimming is expected to increase the amount of sperm stored in the queen spermatheca and, ultimately, enhance male posthumous fitness.

  12. Keskkond / Peep Pobbul

    Index Scriptorium Estoniae

    Pobbul, Peep

    2004-01-01

    Ilmunud ka: 2003 : annual report : [Eesti Raudtee]. - Tallinn, 2004, lk. 40-41; 2003 : godovoi ottshjot : [Eesti Raudtee]. - Tallinn, 2004, lk. 40-41. AS-i Eesti Raudtee keskkonna-alastest projektidest

  13. Optimal Power Management of a DISCO with Integrations of Reliability Considerations and Wind Farm Based on Benders Decomposition

    Directory of Open Access Journals (Sweden)

    M. Baghdadi

    2011-01-01

    Full Text Available This paper presents a comprehensive framework model of a distribution company with security and reliability considerations. A probabilistic wind farm, which is a renewable energy resource, is modeled in this work. The requirement energy of distribution company can be either provided by distribution company's own distributed generations or purchased from power market. Two reliability indices as well as DC load flow equations are also considered in order to satisfy reliability and security constraints, respectively. Since allocating proper spinning reserve improves reliability level, the amount of spinning reserve will be calculated iteratively. In this work, all equations are expressed in a linear fashion in which unit commitment formulation depends on binary variables associated with only on/off of units. The benders decomposition method is used to solve security-based unit commitment.

  14. 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...

  15. 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...

  16. 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...... 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...

  17. Bio-inspired Ant Algorithms: A review

    Directory of Open Access Journals (Sweden)

    Sangita Roy

    2013-05-01

    Full Text Available Ant Algorithms are techniques for optimizing which were coined in the early 1990’s by M. Dorigo. The techniques were inspired by the foraging behavior of real ants in the nature. The focus of ant algorithms is to find approximate optimized problem solutions using artificial ants and their indirect decentralized communications using synthetic pheromones. In this paper, at first ant algorithms are described in details, then transforms to computational optimization techniques: the ACO metaheuristics and developed ACO algorithms. A comparative study of ant algorithms also carried out, followed by past and present trends in AAs applications. Future prospect in AAs also covered in this paper. Finally a comparison between AAs with well-established machine learning techniques were focused, so that combining with machine learning techniques hybrid, robust, novel algorithms could be produces for outstanding result in future.

  18. 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....... Being predatory and organized as superorganisms, ants possess traits making them suitable agents in IPM. Recent works on weaver ants Oecophylla spp. showcase ants as highly efficient pest controllers. A synthesis shows that weaver ants can reduce pest numbers and their damage and increase yields...... 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...

  19. 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

    2017-01-01

    facultative relationships, where ants forage on plants. 2. In a laboratory setupexperiment, weaver ants (Oecophylla smaragdina) were confined to the canopies of coffee (Coffea arabica) seedlings, excluding any ant-to-plant transfer of nutrients via the soil strata. When ants were fed 15N-labelled glycine......-recognised but probably more fluctuating benefit from herbivore protection. Given the worldwide abundance of plant canopies foraged by ants, this nutrient pathway may be of high ecological significance.......1. Nutrient supplies to plants from ants are well known from specialised myrmecophytic symbioses and from plants growing in soil close to ant nests. However, above ground nutrient pathways may play a hitherto largely unrecognised role also in less specialised ant-plant interactions – the numerous...

  20. Uses and updating of the Benders method in the integer-mixed programming in the planning of the electric power systems expansion; Usos y actualizacion del metodo de Benders en la programacion entera-mixta y en la planeacion de la expansion de los sistemas electricos de potencia

    Energy Technology Data Exchange (ETDEWEB)

    De la Torre Vega, Eli

    1997-04-01

    In the first chapter the deduction of the Benders cuts are presented, departing from the properties of duality. Also the properties of the Benders cuts are presented, as well as the initial algorithm of Benders to solve any problem of lineal integer-mixed programming are presented. In the second chapter, of the planning of the expansion of means of generation and transmission in an electric power system is presented and the different structures of the mathematical programming it gives rise to and how the method of Benders can be adapted to these. In the third chapter the theoretical contributions of this work are presented: a) How to initialize the master problem to take advantage of the acquired experience after having solved a similar problem, so that it can be solved more efficiently, the succession of integer-mixed problems of linear programming that arise when solving the problem of the planning of the expansion of generation and transmission means in an electric power system. b) How to generate a master problem whose continuous optimal solution corresponds to the optimal continuous one of the integer-mixed problem, so that the search of integer solutions is made in the vicinity of the optimum continuous. c) How to generate an integer solution, close to the optimum continuous of the integer-mixed problem, that has high probability of being feasible, and that is perhaps the optimal integer solution, in a smaller time than that required to solve it in exact form. In addition, other ideas are presented that can be incorporated to the Benders method. In order to show the effectiveness of the proposed ideas, in chapter 4 the results obtained when solving several problems are presented using: 1. The updated Benders method, 2. The branch and bound method, 3. The update of Benders when adding restrictions and 4. The update of Benders when considered as integer each time to more variables. Finally a summary is made of the achievements, of the conclusions obtained and

  1. Ant Colony Optimization Algorithm for Continuous Domains Based on Position Distribution Model of Ant Colony Foraging

    OpenAIRE

    Liqiang Liu; Yuntao Dai; Jinyu Gao

    2014-01-01

    Ant colony optimization algorithm for continuous domains is a major research direction for ant colony optimization algorithm. In this paper, we propose a distribution model of ant colony foraging, through analysis of the relationship between the position distribution and food source in the process of ant colony foraging. We design a continuous domain optimization algorithm based on the model and give the form of solution for the algorithm, the distribution model of pheromone, the update rules...

  2. 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.

  3. Fungal Adaptations to Mutualistic Life with Ants

    DEFF Research Database (Denmark)

    Kooij, Pepijn Wilhelmus

    that forage on crude substrates such as insect frass and dry plant material, to large colonies of the leaf-cutting ants with several thousands to several million workers that provide live plant material to their fungus gardens. Leaf-cutting ants are the dominant herbivores of the Neo-tropics, and have a major...... on specific enzyme groups and Acromyrmex having an overall high enzyme activity. Finally, I show that the fungal symbiont of the leaf-cutting ant Acromyrmex echinatior produces large amounts of biodegrading enzymes in special structures called gongylidia. The ants eat these structures, but enzymes pass...

  4. GRID SCHEDULING USING ENHANCED ANT COLONY ALGORITHM

    Directory of Open Access Journals (Sweden)

    P. Mathiyalagan

    2010-10-01

    Full Text Available Grid computing is a high performance computing used to solve larger scale computational demands. Task scheduling is a major issue in grid computing systems. Scheduling of tasks is the NP hard problem. The heuristic approach provides optimal solution for NP hard problems .The ant colony algorithm provides optimal solution. The existing ant colony algorithm takes more time to schedule the tasks. In this paper ant colony algorithm improved by enhancing pheromone updating rule such that it schedules the tasks efficiently and better resource utilization. The simulation results prove that proposed method reduces the execution time of tasks compared to existing ant colony algorithm.

  5. 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.

  6. Ilmub suurmeister Evald Okase monograafia / Ants Juske

    Index Scriptorium Estoniae

    Juske, Ants, 1956-

    2009-01-01

    22. aprillil Kumu Kunstimuuseumis esitletavast monograafiast "Evald Okas", mille on kirjutanud Ants Juske, kujundanud Tiit Jürna. Evald Okasest, tema loomingust, elust Jaroslavlis ja rindekunstnikuna

  7. Enhanced ants system and its application

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    NP-hard combinational optimization problem is not solved very well until now. One enhanced ants system based on ants system is advanced after analysis of the deficiencies of existing ants systems. Some improvements are made in state transfer rule and local modification rule. Furthermore, the enhanced ants system can solve NP-hard combinational optimization problem with restraints and condition path. The successful application of TSP problem and transportation net problem indicates that the proposed system has stronger function and higher efficiency than the original system.

  8. Conflict resolution in an ant-plant interaction: Acacia constricta traits reduce ant costs to reproduction.

    Science.gov (United States)

    Nicklen, E Fleur; Wagner, Diane

    2006-05-01

    Many plant species attract ants onto their foliage with food rewards or nesting space. However, ants can interfere with plant reproduction when they visit flowers. This study tests whether Acacia constricta separates visiting ant species temporally or spatially from newly opened inflorescences and pollinators. The diurnal activity patterns of ants and A. constricta pollinators peaked at different times of day, and the activity of pollinators followed the daily dehiscence of A. constricta inflorescences. In addition to being largely temporally separated, ants rarely visited open inflorescences. A floral ant repellent contributes to the spatial separation of ants and inflorescences. In a field experiment, ants of four species were given equal access to inflorescences in different developmental stages. On average, the frequency with which ants made initial, antennal contact with the floral stages did not differ, but ants significantly avoided secondary contact with newly opened inflorescences relative to buds and old inflorescences, and old inflorescences relative to buds. Ants also avoided contact with pollen alone, indicating that pollen is at least one source of the repellent. The results suggest A. constricta has effectively resolved the potential conflict between visiting ants and plant reproduction.

  9. Plants in Your Ants: Using Ant Mounds to Test Basic Ecological Principles

    Science.gov (United States)

    Zettler, Jennifer A.; Collier, Alexander; Leidersdorf, Bil; Sanou, Missa Patrick

    2010-01-01

    Urban students often have limited access to field sites for ecological studies. Ubiquitous ants and their mounds can be used to study and test ecology-based questions. We describe how soil collected from ant mounds can be used to investigate how biotic factors (ants) can affect abiotic factors in the soil that can, in turn, influence plant growth.

  10. Plants in Your Ants: Using Ant Mounds to Test Basic Ecological Principles

    Science.gov (United States)

    Zettler, Jennifer A.; Collier, Alexander; Leidersdorf, Bil; Sanou, Missa Patrick

    2010-01-01

    Urban students often have limited access to field sites for ecological studies. Ubiquitous ants and their mounds can be used to study and test ecology-based questions. We describe how soil collected from ant mounds can be used to investigate how biotic factors (ants) can affect abiotic factors in the soil that can, in turn, influence plant growth.

  11. OLAF BENDER:德国视音频艺术前沿的白色噪音%VISUAL NOISE:CUTTING EDGE OF GERMAN AUDIO

    Institute of Scientific and Technical Information of China (English)

    杜钦

    2009-01-01

    @@ Raster-Noton是当代德国一个重要的电子乐厂牌,由Frank Bretschneider(又名Kornet)和Olaf Bender(又名Byetone)拥有的厂牌Raster,与Carsten Nicolai (又名Alva Nato)拥有的Noton在1999年合并组成,至今已有近十年的历史.

  12. Performance of children with and without learning disabilities on Canter's Background Interference Procedure and Koppitz's scoring system for the Bender test.

    Science.gov (United States)

    Mitchell-Burns, J A

    2000-06-01

    Performance of 66 children, 30 with and 36 without learning disabilities, in four ways using the Bender Visual-motor Gestalt Test was compared. First, the test with the standard Koppitz scoring procedure, second with the Canter Background Interference Procedure sheet using the standard Koppitz scoring procedure; third, the Bender test on a standard sheet of paper using Canter scoring procedure; and fourth, the Canter Background Interference Procedure (BIP) sheet using the Canter scoring procedure. The effectiveness of the Canter procedure was examined when scored with an age-appropriate normative scoring system. This was accomplished by combining the Canter BIP interference sheet with the Koppitz scoring system. The children ranged in age from 6 to 10 years. Using discriminant analysis, all four methods correctly categorized statistically significant percentages of both types of students but there was a significant difference on the Canter BIP sheet using the Canter scoring procedure. This procedure classified students with the least absolute number and percentage of either false negatives or false positives when compared with the other three methods, suggesting that using this scoring method with the Bender Gestalt may be better for identifying younger children with learning disabilities.

  13. 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

  14. Spectacular Batesian mimicry in ants

    Science.gov (United States)

    Ito, Fuminori; Hashim, Rosli; Huei, Yek Sze; Kaufmann, Eva; Akino, Toshiharu; Billen, Johan

    2004-10-01

    The mechanism by which palatable species take advantage of their similarity in appearance to those that are unpalatable, in order to avoid predation, is called Batesian mimicry. Several arthropods are thought to be Batesian mimics of social insects; however, social insects that are Batesian mimics among themselves are rare. In Malaysia we found a possible Batesian mimic in an arboreal ant species, Camponotus sp., which was exclusively observed on foraging trails of the myrmicine ant Crematogaster inflata. The bright yellow and black colouring pattern, as well as the walking behaviour, were very similar in both species. We observed general interactions between the two species, and tested their palatability and the significance of the remarkably similar visual colour patterns for predator avoidance. Prey offered to C. inflata was also eaten by Camponotus workers in spite of their being attacked by C. inflata, indicating that Camponotus sp. is a commensal of C. inflata. An experiment with chicks as potential predators suggests that Camponotus sp. is palatable whereas C. inflata is unpalatable. After tasting C. inflata, the chicks no longer attacked Camponotus sp., indicating that Camponotus sp. is a Batesian mimic of Crematogaster inflata.

  15. Teste de Bender com disléxicos: comparação de dois sistemas de pontuação Bender Test with dyslexics: Comparison of two systems of punctuation

    Directory of Open Access Journals (Sweden)

    Acácia Aparecida Angeli dos Santos

    2007-06-01

    Full Text Available Este estudo teve como objetivo avaliar aspectos maturacionais e disfuncionais referentes à percepção visomotora de disléxicos valendo-se, para isso, do Teste de Bender analisado sob dois sistemas de correção, o sistema de pontuação gradual (B-SPG e o sistema Lacks. Participaram da pesquisa 20 disléxicos com idade entre 9 e 16 anos (M = 12, sendo 16 do sexo masculino e 4 do sexo feminino. Os dados mostraram que a média de erros dos disléxicos foi acima do que é esperado para crianças de nove e dez anos que compõem a amostra normativa do B-SPG. De acordo com o sistema Lacks de pontuação os fatores mais comprometidos na amostra de disléxicos foram referentes a mudanças na forma da gestalt e distorção da gestalt, fatores esses equivalentes à distorção da forma no B-SPG. O índice de correlação entre os dois sistemas foi significativo e alto (r = 0,76.The present study aimed to evaluate maturity and dysfunctional aspects referred to visualmotor perception of dyslexics using for this, the Bender Test analyzed under two correction systems, being the gradual scoring system (B-SPG and Lacks system. Twenty dyslexics have taken part in the research with ages from 9 to 16 years (average=12, being 16 males and 4 females. The data showed the average of mistakes committed by the dyslexics was above the expected for children from nine to ten years who compose the B-SPG normative sample. According to the Lacks scoring system the factors more affected in the sample of dyslexics were referred to changes on the gestalt form and distortions, factors which are equivalent to the form distortions on the B-SPG. The correlation index between these two systems was significant (r = 0.76.

  16. Evidências de validade do bender: sistema de pontuação gradual (B-SPG Evidences of validity of bender: gradual scoring system (B-SPG

    Directory of Open Access Journals (Sweden)

    Ana Paula Porto Noronha

    2007-01-01

    Full Text Available Esse estudo objetivou buscar evidências de validade para o teste de Bender - Sistema de Pontuação Gradual (B-SPG, por meio da investigação das mudanças desenvolvimentais, expressas pela relação entre os escores com a idade. Fizeram parte do estudo 1052 crianças de oito escolas públicas estaduais e municipais de Campinas e região, de pré-escola à 4ª série do ensino fundamental. As idades variaram entre 6 e 10 anos, com uma média de 8,35 anos. Os achados revelaram que conforme aumentou a idade, diminuiu a pontuação obtida pelo B-SPG, indicando que com o aumento da idade, as distorções da cópia progressivamente diminuem. Embora outros estudos sejam recomendados, os resultados aqui apresentados estão em consonância com trabalhos que buscaram a constatação de que é possível encontrar um caráter maturacional nas figuras do teste.This study aimed to gather evidences of validity for the Bender test - Gradual Scoring System (B-SPG, investigating developmental changes based on the relationships between its scores and the ages of the children. The study investigated 1052 children attending from pre-school to fourth grade of eight municipal and state public schools of Campinas (a city in the state of São Paulo, Brazil and the surrounding region. Ages ranged from six to ten years old, with an average of 8,35. The findings indicated that according to the increase of age, the B-SPG scores diminished, suggesting that the distortions progressively diminish as the children become older. Although other studies are suggested, the results presented here are consonant with researches that sought to establish that it is possible too find a maturational character among the figures of the test.

  17. Antthrushes, antpittas, and gnateaters (Aves, Formicariidae) as army ant followers

    OpenAIRE

    Edwin O. Willis

    1984-01-01

    Antthrushes (Formicarius, Chamaeza) sometimes walk around swarms of army ants and capture ground prey, but do not follow ants regularly. Among antpittas, only fast-leaping Pittasoma michleri and P. rufopileatum regularly follow ants. Gnateaters (Conopophaga) follow ants little. All these ground-foraging genera are poorly adapted for rapid flying, and failure to follow ants is perhaps due to inability to evade predators or out fly competitors near groups of birds attracted by ants.

  18. Fire Evacuation using Ant Colony Optimization Algorithm

    National Research Council Canada - National Science Library

    Kanika Singhal; Shashank Sahu

    2016-01-01

    ... planning.The objective of the algorithm is to minimizes the entire rescue time of all evacuees.The ant colony optimization algorithm is used to solve the complications of shortest route planning. Presented paper gives a comparative overview of various emergency scenarios using ant colony optimization algorithm.

  19. Extrafloral nectar fuels ant life in deserts.

    Science.gov (United States)

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

    2014-11-07

    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 desert of northwestern Argentina, we surveyed the richness and phenology of EFN plants and their associated ants and examined the patterns in ant-plant interaction networks. We found that 25 ant species and 11 EFN-bearing plant species were linked together through 96 pairs of associations. Plants bearing EFNs were abundant, representing ca. 19 % of the species encountered in transects and 24 % of the plant cover. Most ant species sampled (ca. 77 %) fed on EF nectar. Interactions showed a marked seasonal pattern: EFN secretion was directly related to plant phenology and correlated with the time of highest ant ground activity. Our results reveal that EFN-mediated interactions are ecologically relevant components of deserts, and that EFN-bearing plants are crucial for the survival of desert ant communities. Published by Oxford University Press on behalf of the Annals of Botany Company.

  20. 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

    2016-01-20

    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.

  1. Dynamical Equilibrium of Interacting Ant Societies

    CERN Document Server

    Leok, B T M

    1996-01-01

    The sustainable biodiversity associated with a specific ecological niche as a function of land area is analysed computationally by considering the interaction of ant societies over a collection of islands. A power law relationship between sustainable species and land area is observed. We will further consider the effect a perturbative inflow of ants has upon the model.

  2. Neuropeptidomics of the carpenter ant Camponotus floridanus.

    Science.gov (United States)

    Schmitt, Franziska; Vanselow, Jens T; Schlosser, Andreas; Kahnt, Jörg; Rössler, Wolfgang; Wegener, Christian

    2015-03-01

    Ants show a rich behavioral repertoire and a highly complex organization, which have been attracting behavioral and sociobiological researchers for a long time. The neuronal underpinnings of ant behavior and social organization are, however, much less understood. Neuropeptides are key signals that orchestrate animal behavior and physiology, and it is thus feasible to assume that they play an important role also for the social constitution of ants. Despite the availability of different ant genomes and in silico prediction of ant neuropeptides, a comprehensive biochemical survey of the neuropeptidergic communication possibilities of ants is missing. We therefore combined different mass spectrometric methods to characterize the neuropeptidome of the adult carpenter ant Camponotus floridanus. We also characterized the local neuropeptide complement in different parts of the nervous and neuroendocrine system, including the antennal and optic lobes. Our analysis identifies 39 neuropeptides encoded by different prepropeptide genes, and in silico predicts new prepropeptide genes encoding CAPA peptides, CNMamide as well as homologues of the honey bee IDLSRFYGHFNT- and ITGQGNRIF-containing peptides. Our data provides basic information about the identity and localization of neuropeptides that is required to anatomically and functionally address the role and significance of neuropeptides in ant behavior and physiology.

  3. Ants, rodents and seed predation in Proteaceae

    African Journals Online (AJOL)

    Ants may reduce seed predation by rapidly transporting and burying seeds in their .... the size and shape of inverted waste paper baskets or b) by securing a lid 5 ... Mimetes experiment was dry for only 3 h before rain set in. Ant activity ceased ...

  4. The Biochemical Toxin Arsenal from Ant Venoms

    Directory of Open Access Journals (Sweden)

    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.

  5. Open Problem: Analyzing Ant Robot Coverage

    Science.gov (United States)

    2010-01-01

    Efficient and inefficient ant coverage methods. Annals of Mathematics and Artificial Intelligence, 31, 41–76. The proofs can be found in the technical...Wagner, I., & Bruckstein, A. (2001). Special issue on ant robotics. Annals of Mathematics and Artificial Intelligence, 31. Wagner, I., Lindenbaum, M

  6. 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.

  7. 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.

  8. 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.

  9. Modified chaotic ant swarm to function optimization

    Institute of Scientific and Technical Information of China (English)

    LI Yu-ying; WEN Qiao-yan; LI Li-xiang

    2009-01-01

    The chaotic ant swarm algorithm (CAS) is an optimization algorithm based on swarm intelligence theory, and it is inspired by the chaotic and self-organizing behavior of the ants in nature. Based on the analysis of the properties of the CAS, this article proposes a variation on the CAS called the modified chaotic ant swarm (MCAS), which employs two novel strategies to significantly improve the performance of the original algorithm. This is achieved by restricting the variables to search ranges and making the global best ant to learn from different ants' best information in the end. The simulation of the MCAS on five benchmark functions shows that the MCAS improves the precision of the solution.

  10. Microclimatic conditions of Lasius flavus ant mounds

    Science.gov (United States)

    Véle, Adam; Holuša, Jaroslav

    2017-05-01

    Like other organisms, ants require suitable microclimatic conditions for their development. Thus, ant species inhabiting colder climates build nest mounds that rise above the soil surface, presumably to obtain heating from solar radiation. Although some ant species construct mounds of organic materials, which generate substantial heat due to microbial metabolism, Lasius flavus mounds consists mostly of soil, not organic material. The use of artificial shading in the current study demonstrated that L. flavus depends on direct solar radiation to regulate the temperature in its mound-like nests. Temperatures were much lower in shaded mounds than in unshaded mounds and were likely low enough in shaded mounds to reduce ant development and reproduction. In areas where L. flavus and similar ants are undesirable, they might be managed by shading.

  11. Uncovering the complexity of ant foraging trails.

    Science.gov (United States)

    Czaczkes, Tomer J; Grüter, Christoph; Jones, Sam M; Ratnieks, Francis L W

    2012-01-01

    The common garden ant Lasius niger use both trail pheromones and memory of past visits to navigate to and from food sources. In a recent paper we demonstrated a synergistic effect between route memory and trail pheromones: the presence of trail pheromones results in experienced ants walking straighter and faster. We also found that experienced ants leaving a pheromone trail deposit less pheromone. Here we focus on another finding of the experiment: the presence of cuticular hydrocarbons (CHCs), which are used as home range markers by ants, also affects pheromone deposition behavior. When walking on a trail on which CHCs are present but trail pheromones are not, experienced foragers deposit less pheromone on the outward journey than on the return journey. The regulatory mechanisms ants use during foraging and recruitment behavior is subtle and complex, affected by multiple interacting factors such as route memory, travel direction and the presence trail pheromone and home-range markings.

  12. Spatiotemporal chemotactic model for ant foraging

    Science.gov (United States)

    Ramakrishnan, Subramanian; Laurent, Thomas; Kumar, Manish; Bertozzi, Andrea L.

    2014-12-01

    In this paper, we present a generic theoretical chemotactic model that accounts for certain emergent behaviors observed in ant foraging. The model does not have many of the constraints and limitations of existing models for ants colony dynamics and takes into account the distinctly different behaviors exhibited in nature by ant foragers in search of food and food ferrying ants. Numerical simulations based on the model show trail formation in foraging ant colonies to be an emergent phenomenon and, in particular, replicate behavior observed in experiments involving the species P. megacephala. The results have broader implications for the study of randomness in chemotactic models. Potential applications include the developments of novel algorithms for stochastic search in engineered complex systems such as robotic swarms.

  13. Microclimatic conditions of Lasius flavus ant mounds

    Science.gov (United States)

    Véle, Adam; Holuša, Jaroslav

    2016-11-01

    Like other organisms, ants require suitable microclimatic conditions for their development. Thus, ant species inhabiting colder climates build nest mounds that rise above the soil surface, presumably to obtain heating from solar radiation. Although some ant species construct mounds of organic materials, which generate substantial heat due to microbial metabolism, Lasius flavus mounds consists mostly of soil, not organic material. The use of artificial shading in the current study demonstrated that L. flavus depends on direct solar radiation to regulate the temperature in its mound-like nests. Temperatures were much lower in shaded mounds than in unshaded mounds and were likely low enough in shaded mounds to reduce ant development and reproduction. In areas where L. flavus and similar ants are undesirable, they might be managed by shading.

  14. Fungal Adaptations to Mutualistic Life with Ants

    DEFF Research Database (Denmark)

    Kooij, Pepijn Wilhelmus

    . However, in rare occasions fungal symbionts might come into contact with symbionts from other colonies. I showed that in both leaf-cutting ant genera incompatibility reactions between fungal strains can avoid intermixing of different strains, and that these reactions strengthen when genetic distance...... successful. To understand the evolutionary development of domestication of the fungus over the phylogeny of the Attine ants, I compared the average number of nuclei per cell for the fungal symbionts, for each of the different groups of fungus-growing ants. I found that the fungal symbionts of the paleo...... is increased. This pattern, however, becomes distorted when fungal symbionts are contested across ant genera. The most important mechanism in the succession of this mutualism of leaf-cutting ants is the controlled degradation of plant material. I show that in the area of Gamboa, Panama, the two leaf...

  15. Optimal Load Dispatch Using Ant Lion Optimization

    Directory of Open Access Journals (Sweden)

    Menakshi Mahendru Nischal

    2015-08-01

    Full Text Available This paper presents Ant lion optimization (ALO technique to solve optimal load dispatch problem. Ant lion optimization (ALO is a novel nature inspired algorithm. The ALO algorithm mimics the hunting mechanism of ant lions in nature. Five main steps of hunting prey such as the random walk of ants, building traps, entrapment of ants in traps, catching preys, and re-building traps are implemented. Optimal load dispatch (OLD is a method of determining the most efficient, low-cost and reliable operation of a power system by dispatching available electricity generation resources to supply load on the system. The primary objective of OLD is to minimize total cost of generation while honoring operational constraints of available generation resources. The proposed technique is implemented on 3, 6 & 20 unit test system for solving the OLD. Numerical results shows that the proposed method has good convergence property and better in quality of solution than other algorithms reported in recent literature.

  16. [The ants: a strategy of population concentration].

    Science.gov (United States)

    Zakharov, A A

    2011-01-01

    Ants are provided with a balanced system of reactions either to the original paucity of socia or to their secondary depopulation. This system can be defined as a strategy of population concentration. Both a successful reproduction of workers and queen fertilization are necessary conditions for ant communities' survival and development. Thus, the anthills must be large enough to ensure optimal conditions for reproduction. It is the strategy of population concentration that is directed to an accelerated attainment (or rehabilitation) by a socium of a state of stable development by way of concentrating the existent ant staff in an accessible number of viable nests. This strategy is realized throughout the life of ant communities by way of (a) fusing the starting family cells left by founder females, (b) fusing small anthills during artificial ant migrations, (c) uniting smaller socia or their joining other anthills, (d) reintegrating the secondary anthills (fragmentants) after an exogenous fragmentation of formicaries. Pooling and the attraction of deficient demographic resources from outside form the most efficient and quickest ways of reaching or restoring the threshold density levels. By realizing this strategy, the ants solve their paramount problems of anthill or settlement conservation at any particular time, as well as of providing some prospects for ant existence in the future. These problems are so vital for ant socia that they appear to hold priority over such other characteristics of utmost importance as genetic kinship or even species identity. The priority of social basics over genetic ones is unequivocally supported through mixed formicaries. A necessary condition for the realization of the strategy of population concentration is tolerance of highly developed social systems to the diversity of forms and to deviations from the norm. The use of one and the same mechanism at all stages of the life both of an individual socium and large ant settlements is

  17. HN solution of stochastic programming using Benders'decomposition method and an application example%基于Benders'分解法的随机规划HN解及应用举例

    Institute of Scientific and Technical Information of China (English)

    冯宏岩; 孟慧慧

    2013-01-01

    随机规划方法在解决不确定环境中的资源配置问题上具有很大优势.笔者介绍并采用了Benders'分解法来求解动态随机规划,依据“阶段”的概念划分出后部子规划,通过前向模拟和后向递归得出最优HN解.这种方法避免了大多数应用问题中确定性等价形式求解时规模过大的问题,同时反映了信息集的更新过程.此外,从“等待观察(WS)”、“此时此刻(HN)”和“期望价值(EV)”3种假设出发分析最优资产配置问题投资策略的特征,采用EVPI和VSS诠释决策过程中信息的价值和随机方法的价值,并给出了实例分析.

  18. Individual Recognition in Ant Queens

    DEFF Research Database (Denmark)

    D'Ettorre, Patrizia; Heinze, Jürgen

    2005-01-01

    recognize each other's unique facial color patterns [3] . Individual recognition is advantageous when dominance hierarchies control the partitioning of work and reproduction 2 and 4 . Here, we show that unrelated founding queens of the ant Pachycondyla villosa use chemical cues to recognize each other......Personal relationships are the cornerstone of vertebrate societies, but insect societies are either too large for individual recognition, or their members were assumed to lack the necessary cognitive abilities 1 and 2 . This paradigm has been challenged by the recent discovery that paper wasps...... perception, was prevented and in tests with anaesthetized queens. The cuticular chemical profiles of queens were neither associated with dominance nor fertility and, therefore, do not represent status badges 5 and 6 , and nestmate queens did not share a common odor. Personal recognition facilitates...

  19. Some enzymic activities of two Australian ant venoms: a jumper ant Myrmecia pilosula and a bulldog ant Myrmecia pyriformis.

    Science.gov (United States)

    Matuszek, M A; Hodgson, W C; King, R G; Sutherland, S K

    1994-12-01

    Venoms from two related Australian ants, a jumper ant (Myrmecia pilosula) and a bulldog ant (Myrmecia pyriformis), were quantitatively analysed for the following enzymic activities: phospholipase A2, phospholipase B, phospholipase C, hyaluronidase, esterase, acid phosphatase, alkaline phosphatase and phosphodiesterase. Both venoms contained phospholipase A2, phospholipase B, hyaluronidase, acid phosphatase and alkaline phosphatase activities. Myrmecia pyriformis venom had significantly greater phospholipase B, acid phosphatase and alkaline phosphatase activities than Myrmecia pilosula venom. No detectable quantities of phospholipase C, esterase or phosphodiesterase activities were found in either venom.

  20. 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.

  1. 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.

  2. Differential Recruitment of Camponotus femoratus (Fabricius) Ants in Response to Ant Garden Herbivory.

    Science.gov (United States)

    Vicente, R E; Dáttilo, W; Izzo, T J

    2014-12-01

    Although several studies have shown that ants can recognize chemical cues from their host plants in ant-plant systems, it is poorly demonstrated in ant gardens (AGs). In this interaction, ant species constantly interact with various epiphyte species. Therefore, it is possible to expect a convergence of chemical signals released by plants that could be acting to ensure that ants are able to recognize and defend epiphyte species frequently associated with AGs. In this study, it was hypothesized that ants recognize and differentiate among chemical stimuli released by AG epiphytes and non-AG epiphytes. We experimentally simulated leaf herbivore damage on three epiphyte species restricted to AGs and a locally abundant understory herb, Piper hispidum, in order to quantify the number of recruited Camponotus femoratus (Fabricius) defenders. When exposed to the AG epiphytes Peperomia macrostachya and Codonanthe uleana leaves, it was observed that the recruitment of C. femoratus workers was, on average, respectively 556% and 246% higher than control. However, the number of ants recruited by the AG epiphyte Markea longiflora or by the non-AG plant did not differ from paper pieces. This indicated that ants could discern between chemicals released by different plants, suggesting that ants can select better plants. These results can be explained by evolutionary process acting on both ants' capability in discerning plants' chemical compounds (innate attraction) or by ants' learning based on the epiphyte frequency in AGs (individual experience). To disentangle an innate behavior, a product of classical coevolutionary process, from an ant's learned behavior, is a complicated but important subject to understand in the evolution of ant-plant mutualisms.

  3. How to be an ant on figs

    Science.gov (United States)

    Bain, Anthony; Harrison, Rhett D.; Schatz, Bertrand

    2014-05-01

    Mutualistic interactions are open to exploitation by one or other of the partners and a diversity of other organisms, and hence are best understood as being embedded in a complex network of biotic interactions. Figs participate in an obligate mutualism in that figs are dependent on agaonid fig wasps for pollination and the wasps are dependent on fig ovules for brood sites. Ants are common insect predators and abundant in tropical forests. Ants have been recorded on approximately 11% of fig species, including all six subgenera, and often affect the fig-fig pollinator interaction through their predation of either pollinating and parasitic wasps. On monoecious figs, ants are often associated with hemipterans, whereas in dioecious figs ants predominantly prey on fig wasps. A few fig species are true myrmecophytes, with domatia or food rewards for ants, and in at least one species this is linked to predation of parasitic fig wasps. Ants also play a role in dispersal of fig seeds and may be particularly important for hemi-epiphytic species, which require high quality establishment microsites in the canopy. The intersection between the fig-fig pollinator and ant-plant systems promises to provide fertile ground for understanding mutualistic interactions within the context of complex interaction networks.

  4. 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.

  5. 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.

  6. Ant colonies for the travelling salesman problem.

    Science.gov (United States)

    Dorigo, M; Gambardella, L M

    1997-01-01

    We describe an artificial ant colony capable of solving the travelling salesman problem (TSP). Ants of the artificial colony are able to generate successively shorter feasible tours by using information accumulated in the form of a pheromone trail deposited on the edges of the TSP graph. Computer simulations demonstrate that the artificial ant colony is capable of generating good solutions to both symmetric and asymmetric instances of the TSP. The method is an example, like simulated annealing, neural networks and evolutionary computation, of the successful use of a natural metaphor to design an optimization algorithm.

  7. Faster-is-slower effect in escaping ants revisited: Ants do not behave like humans

    CERN Document Server

    Parisi, Daniel R; Josens, Roxana

    2014-01-01

    In this work we studied the trajectories, velocities and densities of ants when egressing under controlled levels of stress produced by a chemical repellent at different concentrations. We found that, unlike other animals escaping under life-and-death conditions and pedestrian simulations, ants do not produce a higher density zone near the exit door. Instead, ants are uniformly distributed over the available space allowing for efficient evacuations. Consequently, the faster-is-slower effect observed in ants (Soria et al., 2012) is clearly of a different nature to that predicted by de social force model. In the case of ants, the minimum evacuation time is correlated with the lower probability of taking backward steps. Thus, as biological model ants have important differences that make their use inadvisable for the design of human facilities.

  8. 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 species...

  9. 9 CFR 354.121 - Ante-mortem inspection.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Ante-mortem inspection. 354.121 Section 354.121 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Procedures; Ante-Mortem Inspections § 354.121 Ante-mortem inspection. An ante-mortem inspection of...

  10. Faster-is-slower effect in escaping ants revisited: Ants do not behave like humans

    OpenAIRE

    Parisi, Daniel R.; Soria, Sabrina A; Josens, Roxana

    2014-01-01

    In this work we studied the trajectories, velocities and densities of ants when egressing under controlled levels of stress produced by a chemical repellent at different concentrations. We found that, unlike other animals escaping under life-and-death conditions and pedestrian simulations, ants do not produce a higher density zone near the exit door. Instead, ants are uniformly distributed over the available space allowing for efficient evacuations. Consequently, the faster-is-slower effect o...

  11. Multitasking in a plant-ant interaction: how does Acacia myrtifolia manage both ants and pollinators?

    Science.gov (United States)

    Martínez-Bauer, Angélica E; Martínez, Gerardo Cerón; Murphy, Daniel J; Burd, Martin

    2015-06-01

    Plant associations with protective ants are widespread among angiosperms, but carry the risk that ants will deter pollinators as well as herbivores. Such conflict, and adaptations to ameliorate or prevent the conflict, have been documented in African and neotropical acacias. Ant-acacia associations occur in Australia, but little is known of their ecology. Moreover, recent phylogenetic evidence indicates that Australian acacias are only distantly related to African and American acacias, providing an intercontinental natural experiment in the management of ant-pollinator conflict. We examined four populations of Acacia myrtifolia over a 400-km environmental gradient in southeastern Australia using ant and pollinator exclusion as well as direct observation of ants and pollinators to assess the potential for ant-pollinator conflict to affect seed set. Native bees were the only group of floral visitors whose visitation rates were a significant predictor of fruiting success, although beetles and wasps may play an important role as "insurance" pollinators. We found no increase in pollinator visitation or fruiting success following ant exclusion, even with large sample sizes and effective exclusion. Because ants are facultative visitors to A. myrtifolia plants, their presence may be insufficient to interfere greatly with floral visitors. It is also likely that the morphological location of extrafloral nectaries tends to draw ants away from reproductive parts, although we commonly observed ants on inflorescences, so the spatial separation is not strict. A. myrtifolia appears to maintain a generalized mutualism over a wide geographic range without the need for elaborate adaptations to resolve ant-pollinator conflict.

  12. Deterministic ants in labirynth -- information gained by map sharing

    CERN Document Server

    Malinowski, Janusz

    2014-01-01

    A few of ant robots are dropped to a labirynth, formed by a square lattice with a small number of nodes removed. Ants move according to a deterministic algorithm designed to explore all corridors. Each ant remembers the shape of corridors which she has visited. Once two ants met, they share the information acquired. We evaluate how the time of getting a complete information by an ant depends on the number of ants, and how the length known by an ant depends on time. Numerical results are presented in the form of scaling relations.

  13. Fire disturbance disrupts an acacia ant-plant mutualism in favor of a subordinate ant species.

    Science.gov (United States)

    Sensenig, Ryan L; Kimuyu, Duncan K; Ruiz Guajardo, Juan C; Veblen, Kari E; Riginos, Corinna; Young, Truman P

    2017-05-01

    Although disturbance theory has been recognized as a useful framework in examining the stability of ant-plant mutualisms, very few studies have examined the effects of fire disturbance on these mutualisms. In myrmecophyte-dominated savannas, fire and herbivory are key drivers that could influence ant-plant mutualisms by causing complete colony mortality and/or decreasing colony size, which potentially could alter dominance hierarchies if subordinate species are more fire resilient. We used a large-scale, replicated fire experiment to examine long-term effects of fire on acacia-ant community composition. To determine if fire shifted ant occupancy from a competitive dominant to a subordinate ant species, we surveyed the acacia-ant community in 6-7 yr old burn sites and examined how the spatial scale of these burns influenced ant community responses. We then used two short-term fire experiments to explore possible mechanisms for the shifts in community patterns observed. Because survival of ant colonies is largely dependent on their ability to detect and escape an approaching fire, we first tested the evacuation response of all four ant species when exposed to smoke (fire signal). Then to better understand how fire and its interaction with large mammal herbivory affect the density of ants per tree, we quantified ant worker density in small prescribed burns within herbivore exclusion plots. We found clear evidence suggesting that fire disturbance favored the subordinate ant Crematogaster nigriceps more than the dominant and strong mutualist ant C. mimosae, whereby C. nigriceps (1) was the only species to occupy a greater proportion of trees in 6-7 yr old burn sites compared to unburned sites, (2) had higher burn/unburn tree ratios with increasing burn size, and (3) evacuated significantly faster than C. mimosae in the presence of smoke. Fire and herbivory had opposite effects on ant density per meter of branch for both C. nigriceps and C. mimosae, with fire

  14. Mutualism exploitation: predatory drosophilid larvae sugar-trap ants and jeopardize facultative ant-plant mutualism.

    Science.gov (United States)

    Vidal, Mayra C; Sendoya, Sebastian F; Oliveira, Paulo S

    2016-07-01

    An open question in the evolutionary ecology of ant-plant facultative mutualism is how other members of the associated community can affect the interaction to a point where reciprocal benefits are disrupted. While visiting Qualea grandiflora shrubs to collect sugary rewards at extrafloral nectaries, tropical savanna ants deter herbivores and reduce leaf damage. Here we show that larvae of the fly Rhinoleucophenga myrmecophaga, which develop on extrafloral nectaries, lure potentially mutualistic, nectar-feeding ants and prey on them. Foraging ants spend less time on fly-infested foliage. Field experiments showed that predation (or the threat of predation) on ants by fly larvae produces cascading effects through three trophic levels, resulting in fewer protective ants on leaves, increased numbers of chewing herbivores, and greater leaf damage. These results reveal an undocumented mode of mutualism exploitation by an opportunistic predator at a plant-provided food source, jeopardizing ant-derived protection services to the plant. Our study documents a rather unusual case of predation of adult ants by a dipteran species and demonstrates a top-down trophic cascade within a generalized ant-plant mutualism. © 2016 by the Ecological Society of America.

  15. KohonAnts: A Self-Organizing Ant Algorithm for Clustering and Pattern Classification

    CERN Document Server

    Fernandes, C; Merelo, J J; Ramos, V; Laredo, J L J

    2008-01-01

    In this paper we introduce a new ant-based method that takes advantage of the cooperative self-organization of Ant Colony Systems to create a naturally inspired clustering and pattern recognition method. The approach considers each data item as an ant, which moves inside a grid changing the cells it goes through, in a fashion similar to Kohonen's Self-Organizing Maps. The resulting algorithm is conceptually more simple, takes less free parameters than other ant-based clustering algorithms, and, after some parameter tuning, yields very good results on some benchmark problems.

  16. 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....

  17. Discrimination Behavior in the Supercolonial Pharaoh Ant

    DEFF Research Database (Denmark)

    Pontieri, Luigi

    an increasing need to understand which factors promote the ecological dominance of these species, and particularly how the discrimination of both conspecifics and heterospecifics (including parasites) might influence structure and ecological success of invasive populations. In this PhD thesis I investigated...... the discrimination behavior of the invasive pharaoh ant (Monomorium pharaonis) as a model for other invasive and supercolonial ant species. The pharaoh ant is one of the few ant species that can be reared in the laboratory for many generations. Furthermore, the possibility to do controlled crosses of colonies...... provides the unique opportunity to establish colonies of different genetic composition. These traits make this species a suitable study subject to set up behavioral experiments that aim to investigate which factors, and to which extent, might influence the inter- and intraspecific discrimination abilities...

  18. Rose Atoll - Eradication of Invasive Ants

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — There are at least 9 species of ants introduced to Rose Atoll, including species that tend to scale insects that are devastating the Pisonia grandis trees on the 15...

  19. Discrimination Behavior in the Supercolonial Pharaoh Ant

    DEFF Research Database (Denmark)

    Pontieri, Luigi

    an increasing need to understand which factors promote the ecological dominance of these species, and particularly how the discrimination of both conspecifics and heterospecifics (including parasites) might influence structure and ecological success of invasive populations. In this PhD thesis I investigated...... the discrimination behavior of the invasive pharaoh ant (Monomorium pharaonis) as a model for other invasive and supercolonial ant species. The pharaoh ant is one of the few ant species that can be reared in the laboratory for many generations. Furthermore, the possibility to do controlled crosses of colonies...... provides the unique opportunity to establish colonies of different genetic composition. These traits make this species a suitable study subject to set up behavioral experiments that aim to investigate which factors, and to which extent, might influence the inter- and intraspecific discrimination abilities...

  20. 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

    , 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...

  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 t...

  2. An Improved Heuristic Ant-Clustering Algorithm

    Institute of Scientific and Technical Information of China (English)

    Yunfei Chen; Yushu Liu; Jihai Zhao

    2004-01-01

    An improved heuristic ant-clustering algorithm(HAC)is presented in this paper. A device of 'memory bank' is proposed,which can bring forth heuristic knowledge guiding ant to move in the bi-dimension grid space.The device experiments on real data sets and synthetic data sets.The results demonstrate that HAC has superiority in misclassification error rate and runtime over the classical algorithm.

  3. Ants (Formicidae): models for social complexity.

    Science.gov (United States)

    Smith, Chris R; Dolezal, Adam; Eliyahu, Dorit; Holbrook, C Tate; Gadau, Jürgen

    2009-07-01

    The family Formicidae (ants) is composed of more than 12,000 described species that vary greatly in size, morphology, behavior, life history, ecology, and social organization. Ants occur in most terrestrial habitats and are the dominant animals in many of them. They have been used as models to address fundamental questions in ecology, evolution, behavior, and development. The literature on ants is extensive, and the natural history of many species is known in detail. Phylogenetic relationships for the family, as well as within many subfamilies, are known, enabling comparative studies. Their ease of sampling and ecological variation makes them attractive for studying populations and questions relating to communities. Their sociality and variation in social organization have contributed greatly to an understanding of complex systems, division of labor, and chemical communication. Ants occur in colonies composed of tens to millions of individuals that vary greatly in morphology, physiology, and behavior; this variation has been used to address proximate and ultimate mechanisms generating phenotypic plasticity. Relatedness asymmetries within colonies have been fundamental to the formulation and empirical testing of kin and group selection theories. Genomic resources have been developed for some species, and a whole-genome sequence for several species is likely to follow in the near future; comparative genomics in ants should provide new insights into the evolution of complexity and sociogenomics. Future studies using ants should help establish a more comprehensive understanding of social life, from molecules to colonies.

  4. Visual scene perception in navigating wood ants.

    Science.gov (United States)

    Lent, David D; Graham, Paul; Collett, Thomas S

    2013-04-22

    Ants, like honeybees, can set their travel direction along foraging routes using just the surrounding visual panorama. This ability gives us a way to explore how visual scenes are perceived. By training wood ants to follow a path in an artificial scene and then examining their path within transformed scenes, we identify several perceptual operations that contribute to the ants' choice of direction. The first is a novel extension to the known ability of insects to compute the "center of mass" of large shapes: ants learn a desired heading toward a point on a distant shape as the proportion of the shape that lies to the left and right of the aiming point--the 'fractional position of mass' (FPM). The second operation, the extraction of local visual features like oriented edges, is familiar from studies of shape perception. Ants may use such features for guidance by keeping them in desired retinal locations. Third, ants exhibit segmentation. They compute the learned FPM over the whole of a simple scene, but over a segmented region of a complex scene. We suggest how the three operations may combine to provide efficient directional guidance. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. 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.

  6. 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.

  7. 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.

  8. Entangled active matter: From cells to ants

    Science.gov (United States)

    Hu, D. L.; Phonekeo, S.; Altshuler, E.; Brochard-Wyart, F.

    2016-07-01

    Both cells and ants belong to the broad field of active matter, a novel class of non-equilibrium materials composed of many interacting units that individually consume energy and collectively generate motion or mechanical stresses. However cells and ants differ from fish and birds in that they can support static loads. This is because cells and ants can be entangled, so that individual units are bound by transient links. Entanglement gives cells and ants a set of remarkable properties usually not found together, such as the ability to flow like a fluid, spring back like an elastic solid, and self-heal. In this review, we present the biology, mechanics and dynamics of both entangled cells and ants. We apply concepts from soft matter physics and wetting to characterize these systems as well as to point out their differences, which arise from their differences in size. We hope that our viewpoints will spur further investigations into cells and ants as active materials, and inspire the fabrication of synthetic active matter.

  9. 螺旋埋弧焊管机组三辊弯板机的控制%Controlling Three-roll Plate Bender of SAWH Pipe Unit

    Institute of Scientific and Technical Information of China (English)

    崔远洋

    2012-01-01

    介绍了螺旋埋弧焊管机组三辊弯板成型原理,分析了弯板三辊位置控制不佳对焊缝质量的影响及造成的危害,指出了弯板机轧辊位置控制的重要性及具体措施.在三辊弯板成型工艺中,成型辊位置的优化设计时,建议采用“不同管径选择与之相匹配的1#,3#辊的倾角”设计三辊弯板成型的位置.不建议采用“不同管径均选择固定的1#辊、3#辊高度”来设计三辊弯板成型位置和“不同管径均选择固定的1#辊、3#辊中心距”来设计三辊弯板成型位置.%In this article, it introduced forming principle of three-roll plate bender, analyzed the influence and damage to weld quality because of poor control of three-roll plate bender position, pointed out the importance of controlling plate bender roll position and detailed measures. In optimization design of forming roll position, it suggests using different pipe diameter is matched with corresponding obliquity of 1# and 3# roll, and does not suggest using different pipe diameter is all matched with fixed height of 1# and 3# roll and different pipe diameter is all matched with fixed center distance of I# and 3# roll.

  10. Bacterial associates of arboreal ants and their putative functions in an obligate ant-plant mutualism.

    Science.gov (United States)

    Eilmus, Sascha; Heil, Martin

    2009-07-01

    Bacterial communities are highly diverse and have great ecological importance. In the present study, we used an in silico analysis of terminal restriction fragments (tRF) to characterize the bacterial community of the plant ant Pseudomyrmex ferrugineus. This species is an obligate inhabitant of Acacia myrmecophytes and feeds exclusively on plant-derived food sources. Ants are the dominant insect group in tropical rain forests. Associations of ants with microbes, which contribute particularly to the ants' nitrogen nutrition, could allow these insects to live on mostly or entirely plant-based diets and could thus contribute to the explanation of the high abundances that are reached by tropical ants. We found tRF patterns representing at least 30 prokaryotic taxa, of which the Acidobacteria, Actinobacteria, Bacteroidetes, Firmicutes, Planctomycetes, Proteobacteria, and Spirochaetes comprised 93%. Because most bacterial taxa were found in all ant-derived samples studied and because the bacteria detected on the ants' host plant revealed little overlap with this community, we regard our results as reliably representing the bacterial community that is associated with P. ferrugineus. Genera with a likely function as ant symbionts were Burkholderia, Pantoea, Weissella, and several members of the Enterobacteriaceae. The presence of these and various other groups was confirmed via independent PCR and cultivation approaches. Many of the bacteria that we detected belong to purportedly N-fixing taxa. Bacteria may represent important further partners in ant-plant mutualisms, and their influences on ant nutrition can contribute to the extraordinary abundance and evolutionary success of tropical arboreal ants.

  11. Bender Gestalt Visual-Motor test – Sistema de Pontuação Gradual (B-SPG): A study with different samples

    OpenAIRE

    Ana Paula Porto Noronha; Fabian Javier Marin Rueda; Acacia Aparecida Angeli dos Santos

    2013-01-01

    The aim in this study was to analyze differences between children’s performances on the Bender – Sistema de Pontuação Gradual (B-SPG) [Gradual Scoring System] in the states of Minas Gerais and Paraíba, and to compare them with the results presented in the test manual. The participants were 511 children, both sexes, aged 6-10 years ( M = 8.21, SD = 1.33), and 50.7% male. The children were from two states, Minas Gerais ( n = 298, 58.3%) and Paraiba ( n = 213, 41.7%). The SPG was administered co...

  12. Bender Gestalt Visual-Motor test – Sistema de Pontuação Gradual (B-SPG): A study with different samples

    OpenAIRE

    Noronha, Ana Paula Porto; Rueda, Fabian Javier Marin; Santos,Acacia Aparecida Angeli dos

    2013-01-01

    The aim in this study was to analyze differences between children’s performances on the Bender – Sistema de Pontuação Gradual (B-SPG) [Gradual Scoring System] in the states of Minas Gerais and Paraíba, and to compare them with the results presented in the test manual. The participants were 511 children, both sexes, aged 6-10 years ( M = 8.21, SD = 1.33), and 50.7% male. The children were from two states, Minas Gerais ( n = 298, 58.3%) and Paraiba ( n = 213, 41.7%). ...

  13. Determination of sensitivity, specificity and cut off point of visual- Motor Bender Gestalt Test in the diagnosis of traumatic brain injury

    Directory of Open Access Journals (Sweden)

    tayebeh Rezaie nasab

    2013-02-01

    Results: In this study, cut-off point was calculated as 6.5%, sensitivity as 55.8%, characteristic as 81.2%, and the area under the Roc curve as 0.69. Moreover, positive predictive value, negative predictive value and efficiency were 95.08%, 22.03%, and 59.17%, respectively. Conclusion: Results of this study revealed that Bender Gestalt Test is relatively weak in diagnosis of mild TBI. Hence, its characteristic is high and it was successful in diagnosing healthy individuals.

  14. Relación entre maduración, sexo y nivel socio-económico a través del Test Guestaltico Visomotor de Bender

    OpenAIRE

    Ráez de Ramírez, Matilde; Thorne, Cecilia; Martinez, Patricia; Niño de Guzmán, Isabel; Rossel, Zoila; Twanama, Walter

    1986-01-01

    The present study explores the relation between age, sex and socio-economical level in 1,019 children from 5 years to 1 O years, 11 months with the Bender Gestalt Test, using the Kippitz Developmental Scoring System. No significant differences were found according to sex or socio-economical level. Comparing the results with those of Koppitz, significant differences were found in 8 of the 12 groups studied. It was also found that the test is only developmental untill 9 years, just as Taylor & ...

  15. Solution to the problem of ant being stuck by ant colony routing algorithm

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jing; TONG Wei-ming

    2009-01-01

    Many ant colony routing (ACR) algorithms have been presented in recent years, but few have studied the problem that ants will get stuck with probability in any terminal host when they are searching paths to route packets around a network. The problem has to be faced when designing and implementing the ACR algorithm. This article analyzes in detail the differences between the ACR and the ant colony optimization (ACO). Besides, particular restrictions on the ACR are pointed out and the three causes of ant being-stuck problem are obtained. Furthermore, this article proposes a new ant searching mechanism through dual path-checking and online routing loop removing by every intermediate node an ant visited and the destination host respectively, to solve the problem of ant being stuck and routing loop simultaneously. The result of numerical simulation is abstracted from one real network. Compared with existing two typical ACR algorithms, it shows that the proposed algorithm can settle the problem of ant being stuck and achieve more effective searching outcome for optimization path.

  16. Applied Ecology and Control of Imported Fire Ants and Argentine Ants

    Science.gov (United States)

    The red imported fire ant, Solenopsis invicta Buren, and Argentine ant, Linepithema humile (Mayr), are invasive species that are major pests in urban, natural, and agricultural habitats. The goal of this dissertation was to study aspects the chemical sensitivity, behavior, and ecology of each specie...

  17. Taxonomic and functional ecology of montane ants

    Directory of Open Access Journals (Sweden)

    Tom Rhys Bishop

    2017-04-01

    Full Text Available Why is biological diversity distributed in the way that it is? This question has been central to ecology and biogeography for centuries and is of great importance for pure and applied reasons. I use a functional trait view of ecology to complement standard sampling protocols to better understand the distribution and structure of ant (Hymenoptera: Formicidae diversity across mountains. I use a long-term dataset of ant diversity and abundance, combined with a recently collected morphological trait dataset to examine how the alpha and beta diversity of ants responds to changes in temperature along an extensive elevational gradient in southern Africa. In addition, I link morphological thermoregulatory traits to each other and to the environment with a new database of ant elevational abundances from across the globe. Finally, I analyse how physiological thermal tolerances vary and constrain foraging patterns in montane ants. I find that temperature is a strong driver of both alpha and beta diversity patterns. In addition, morphological traits such as colour and body size are found to have a significant relationship to ambient temperatures. This relationship also implies that the relative abundances of different ant species change depending on their thermoregulatory traits (colour and body size and the surrounding thermal environment. Furthermore, the critical thermal minimum (CTmin of the ant species investigated and the lowest environmental temperatures are found to be key in constraining foraging activity patterns. The data presented here strengthen and link existing ideas about how thermoregulation can influence ecological communities and also suggests important ways in which diversity patterns may change in the future.

  18. Ecology of a fig ant-plant

    Science.gov (United States)

    Harrison, Rhett D.

    2014-05-01

    Mutualistic interactions are embedded in networks of interactions that affect the benefits accruing to the mutualistic partners. Figs and their pollinating wasps are engaged in an obligate mutualism in which the fig is dependent on the fig pollinator for pollination services and the pollinator is dependent on fig ovules for brood sites. This mutualism is exploited by non-pollinating fig wasps that utilise the same ovules, but do not provide a pollination service. Most non-pollinating wasps oviposit from outside the inflorescence (syconium), where they are vulnerable to ant predation. Ficus schwarzii is exposed to high densities of non-pollinating wasps, but Philidris sp. ants patrolling the syconia prevent them from ovipositing. Philidris rarely catch wasps, but the fig encourages the patrolling by providing a reward through extra-floral nectaries on the surface of syconia. Moreover, the reward is apparently only produced during the phase when parasitoids are ovipositing. An ant-exclusion experiment demonstrated that, in the absence of ants, syconia were heavily attacked and many aborted as a consequence. Philidris was normally rare on the figs during the receptive phase or at the time of day when wasp offspring are emerging, so predation on pollinators was limited. However, Myrmicaria sp. ants, which only occurred on three trees, preyed substantially on pollinating as well as non-pollinating wasps. F. schwarzii occurs in small clusters of trees and has an exceptionally rapid crop turnover. These factors appear to promote high densities of non-pollinating wasps and, as a consequence, may have led to both a high incidence of ants on trees and increased selective pressure on fig traits that increase the payoffs of the fig-ant interaction for the fig. The fig receives no direct benefit from the reward it provides, but protects pollinating wasps that will disperse its pollen.

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

    DEFF Research Database (Denmark)

    Offenberg, Hans Joachim

    2011-01-01

    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...... 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...... (Fabricius) was tested under laboratory conditions. Of the two types of food offered, the ants ingested 76% pure sucrose and 24% insect prey (dry weights) leading to ECI’s of 29% and 39% including brood only or brood plus imago gain, respectively. Based on Thai sugar and protein food costs and ant brood...

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

    DEFF Research Database (Denmark)

    Offenberg, Hans Joachim

    2011-01-01

    Canopy dwelling weaver ants are widely distributed throughout the Old World Tropics where they build up high densities on their host trees. If managed properly the high number of ants will control a range of pest insects and benefit crop production. Simultaneously the ant larvae production, fuelled...... 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...

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

    DEFF Research Database (Denmark)

    Offenberg, Hans Joachim

    2011-01-01

    (Fabricius) was tested under laboratory conditions. Of the two types of food offered, the ants ingested 76% pure sucrose and 24% insect prey (dry weights) leading to ECI’s of 29% and 39% including brood only or brood plus imago gain, respectively. Based on Thai sugar and protein food costs and ant brood......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...... 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...

  2. The descent of ant: field-measured performance of gliding ants.

    Science.gov (United States)

    Munk, Yonatan; Yanoviak, Stephen P; Koehl, M A R; Dudley, Robert

    2015-05-01

    Gliding ants avoid predatory attacks and potentially mortal consequences of dislodgement from rainforest canopy substrates by directing their aerial descent towards nearby tree trunks. The ecologically relevant measure of performance for gliding ants is the ratio of net horizontal to vertical distance traveled over the course of a gliding trajectory, or glide index. To study variation in glide index, we measured three-dimensional trajectories of Cephalotes atratus ants gliding in natural rainforest habitats. We determined that righting phase duration, glide angle, and path directness all significantly influence variation in glide index. Unsuccessful landing attempts result in the ant bouncing off its target and being forced to make a second landing attempt. Our results indicate that ants are not passive gliders and that they exert active control over the aerodynamic forces they experience during their descent, despite their apparent lack of specialized control surfaces. © 2015. Published by The Company of Biologists Ltd.

  3. Ant colony optimization algorithm for continuous domains based on position distribution model of ant colony foraging.

    Science.gov (United States)

    Liu, Liqiang; Dai, Yuntao; Gao, Jinyu

    2014-01-01

    Ant colony optimization algorithm for continuous domains is a major research direction for ant colony optimization algorithm. In this paper, we propose a distribution model of ant colony foraging, through analysis of the relationship between the position distribution and food source in the process of ant colony foraging. We design a continuous domain optimization algorithm based on the model and give the form of solution for the algorithm, the distribution model of pheromone, the update rules of ant colony position, and the processing method of constraint condition. Algorithm performance against a set of test trials was unconstrained optimization test functions and a set of optimization test functions, and test results of other algorithms are compared and analyzed to verify the correctness and effectiveness of the proposed algorithm.

  4. Ant Colony Optimization Algorithm for Continuous Domains Based on Position Distribution Model of Ant Colony Foraging

    Directory of Open Access Journals (Sweden)

    Liqiang Liu

    2014-01-01

    Full Text Available Ant colony optimization algorithm for continuous domains is a major research direction for ant colony optimization algorithm. In this paper, we propose a distribution model of ant colony foraging, through analysis of the relationship between the position distribution and food source in the process of ant colony foraging. We design a continuous domain optimization algorithm based on the model and give the form of solution for the algorithm, the distribution model of pheromone, the update rules of ant colony position, and the processing method of constraint condition. Algorithm performance against a set of test trials was unconstrained optimization test functions and a set of optimization test functions, and test results of other algorithms are compared and analyzed to verify the correctness and effectiveness of the proposed algorithm.

  5. Ants as shell collectors: notes on land snail shells found around ant nests

    Directory of Open Access Journals (Sweden)

    Barna Páll-Gergely

    2009-03-01

    Full Text Available We investigated the shell collecting activities of harvester ants (Messor spp. in semi-arid grasslands and shrubs in Turkey. We found eleven species of snails in the area, two of them were not collected by ants. Eight – mainly small sized – snail species were found on ant nests in a habitat characterized by shrubs, three in rocky grassland and four in a grassland habitat. Some shells (e.g. Chondrus zebrula tantalus, Multidentula ovularis might be taken into the nests, and we hypothesise that some of these snail species are consumed by ants (Monacha spp.. From a fauna inventory perspective, shell collecting activities of harvester ant may help malacologists to find snail species which are normally hidden for a specialist (e.g. Oxychilus hydatinus, Cecilioides spp. due to their special habits.

  6. 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...

  7. Impacts of residual insecticide barriers on perimeter-invading ants, with particular reference to the odorous house ant, Tapinoma sessile.

    Science.gov (United States)

    Scharf, Michael E; Ratliff, Catina R; Bennett, Gary W

    2004-04-01

    Three liquid insecticide formulations were evaluated as barrier treatments against perimeter-invading ants at a multifamily housing complex in West Lafayette, IN. Several ant species were present at the study site, including (in order of abundance) pavement ant, Tetramorium caespitum (L.); honey ant, Prenolepis imparis (Say); odorous house ant, Tapinoma sessile (Say); thief ant, Solenopsis molesta (Say); acrobat ant, Crematogaster ashmeadi (Mayr); crazy ant, Paratrechina longicornis (Latrielle), field ants, Formica spp.; and carpenter ant Camponotus pennsylvanicus (DeGeer). Studies began in May 2001 and concluded 8 wk later in July. Individual replicate treatments were placed 0.61 in (2 feet) up and 0.92 m (3 feet) out from the ends of 46.1 by 10.1-m (151 by 33-foot) apartment buildings. Ant sampling was performed with 10 placements of moist cat food for 1 h within treatment zones, followed by capture and removal of recruited ants for later counting. All treatments led to substantial reductions in ant numbers relative to untreated controls. The most effective treatment was fipronil, where 2% of before-treatment ant numbers were present at 8 wk after treatment. Both imidacloprid and cyfluthrin barrier treatments had efficacy comparative with fipronil, but to 4 and 2 wk, respectively. Odorous house ants were not sampled before treatment. Comparisons of ant species composition between treatments and controls revealed an increase in odorous house ant frequencies at 1-8 wk after treatment in treated locations only. These results demonstrate efficacy for both nonrepellent and repellent liquid insecticides as perimeter treatments for pest ants. In addition, our findings with odorous house ant highlight an apparent invasive-like characteristic of this species that may contribute to its dramatic increase in structural infestation rates in many areas of the United States.

  8. Fossil evidence for the early ant evolution

    Science.gov (United States)

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

    2008-02-01

    Ants are one of the most studied insects in the world; and the literature devoted to their origin and evolution, systematics, ecology, or interactions with plants, fungi and other organisms is prolific. However, no consensus yet exists on the age estimate of the first Formicidae or on the origin of their eusociality. We review the fossil and biogeographical record of all known Cretaceous ants. We discuss the possible origin of the Formicidae with emphasis on the most primitive subfamily Sphecomyrminae according to its distribution and the Early Cretaceous palaeogeography. And we review the evidence of true castes and eusociality of the early ants regarding their morphological features and their manner of preservation in amber. The mid-Cretaceous amber forest from south-western France where some of the oldest known ants lived, corresponded to a moist tropical forest close to the shore with a dominance of gymnosperm trees but where angiosperms (flowering plants) were already diversified. This palaeoenvironmental reconstruction supports an initial radiation of ants in forest ground litter coincident with the rise of angiosperms, as recently proposed as an ecological explanation for their origin and successful evolution.

  9. Lycaenid Caterpillar Secretions Manipulate Attendant Ant Behavior.

    Science.gov (United States)

    Hojo, Masaru K; Pierce, Naomi E; Tsuji, Kazuki

    2015-08-31

    Mutualistic interactions typically involve the exchange of different commodities between species. Nutritious secretions are produced by a number of insects and plants in exchange for services such as defense. These rewards are valuable metabolically and can be used to reinforce the behavior of symbiotic partners that can learn and remember them effectively. We show here novel effects of insect exocrine secretions produced by caterpillars in modulating the behavior of attendant ants in the food-for-defense interaction between lycaenid butterflies and ants. Reward secretions from the dorsal nectary organ (DNO) of Narathura japonica caterpillars function to reduce the locomotory activities of their attendant ants, Pristomyrmex punctatus workers. Moreover, workers that feed from caterpillar secretions are significantly more likely to show aggressive responses to eversion of the tentacle organs of the caterpillars. Analysis of the neurogenic amines in the brains of workers that consumed caterpillar secretions showed a significant decrease in levels of dopamine compared with controls. Experimental treatments in which reserpine, a known inhibitor of dopamine in Drosophila, was fed to workers similarly reduced their locomotory activity. We conclude that DNO secretions of lycaenid caterpillars can manipulate attendant ant behavior by altering dopaminergic regulation and increasing partner fidelity. Unless manipulated ants also receive a net nutritional benefit from DNO secretions, this suggests that similar reward-for-defense interactions that have been traditionally considered to be mutualisms may in fact be parasitic in nature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. 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.

  11. 基于广义Benders分解的启发式机组组合优化%A Generalized Benders Decomposition Based Heuristic Algorithm for Unit Commitment

    Institute of Scientific and Technical Information of China (English)

    李颖浩; 郭瑞鹏

    2012-01-01

    电力系统机组组合问题是一个高维、离散、非线性的工程优化问题。提出了一种基于Benders分解的启发式算法。该算法一方面充分利用研究时段负荷曲线的特征,将问题进行解耦,减小被研究问题的规模。另一方面,利用Benders分解算法在混合整数规划中的有效性,提高了解决问题的效率。算例表明该方法效率高、结果稳定,有较好的实用价值。%Unit commitment (UC) of power system is a high dimensional, nonlinear and mixed-integer engineering optimization problem. To solve this problem a generalized Benders decomposition based heuristic algorithm is proposed. On the one hand the characteristics of load curve in the time-interval being researched are fully utilized to decouple the problem and to decrease the scale of the problem, on the other hand using the effectiveness of Benders algorithm is solving mixed-integer programming problem the efficiency of solving the problem is improved. Results of calculation example show that the proposed algorithm is efficient and practicable.

  12. Detection of mitochondrial COII DNA sequences in ant guts as a method for assessing termite predation by ants.

    Science.gov (United States)

    Fayle, Tom M; Scholtz, Olivia; Dumbrell, Alex J; Russell, Stephen; Segar, Simon T; Eggleton, Paul

    2015-01-01

    Termites and ants contribute more to animal biomass in tropical rain forests than any other single group and perform vital ecosystem functions. Although ants prey on termites, at the community level the linkage between these groups is poorly understood. Thus, assessing the distribution and specificity of ant termitophagy is of considerable interest. We describe an approach for quantifying ant-termite food webs by sequencing termite DNA (cytochrome c oxidase subunit II, COII) from ant guts and apply this to a soil-dwelling ant community from tropical rain forest in Gabon. We extracted DNA from 215 ants from 15 species. Of these, 17.2 % of individuals had termite DNA in their guts, with BLAST analysis confirming the identity of 34.1 % of these termites to family level or better. Although ant species varied in detection of termite DNA, ranging from 63 % (5/7; Camponotus sp. 1) to 0 % (0/7; Ponera sp. 1), there was no evidence (with small sample sizes) for heterogeneity in termite consumption across ant taxa, and no evidence for species-specific ant-termite predation. In all three ant species with identifiable termite DNA in multiple individuals, multiple termite species were represented. Furthermore, the two termite species that were detected on multiple occasions in ant guts were in both cases found in multiple ant species, suggesting that ant-termite food webs are not strongly compartmentalised. However, two ant species were found to consume only Anoplotermes-group termites, indicating possible predatory specialisation at a higher taxonomic level. Using a laboratory feeding test, we were able to detect termite COII sequences in ant guts up to 2 h after feeding, indicating that our method only detects recent feeding events. Our data provide tentative support for the hypothesis that unspecialised termite predation by ants is widespread and highlight the use of molecular approaches for future studies of ant-termite food webs.

  13. Detection of mitochondrial COII DNA sequences in ant guts as a method for assessing termite predation by ants.

    Directory of Open Access Journals (Sweden)

    Tom M Fayle

    Full Text Available Termites and ants contribute more to animal biomass in tropical rain forests than any other single group and perform vital ecosystem functions. Although ants prey on termites, at the community level the linkage between these groups is poorly understood. Thus, assessing the distribution and specificity of ant termitophagy is of considerable interest. We describe an approach for quantifying ant-termite food webs by sequencing termite DNA (cytochrome c oxidase subunit II, COII from ant guts and apply this to a soil-dwelling ant community from tropical rain forest in Gabon. We extracted DNA from 215 ants from 15 species. Of these, 17.2 % of individuals had termite DNA in their guts, with BLAST analysis confirming the identity of 34.1 % of these termites to family level or better. Although ant species varied in detection of termite DNA, ranging from 63 % (5/7; Camponotus sp. 1 to 0 % (0/7; Ponera sp. 1, there was no evidence (with small sample sizes for heterogeneity in termite consumption across ant taxa, and no evidence for species-specific ant-termite predation. In all three ant species with identifiable termite DNA in multiple individuals, multiple termite species were represented. Furthermore, the two termite species that were detected on multiple occasions in ant guts were in both cases found in multiple ant species, suggesting that ant-termite food webs are not strongly compartmentalised. However, two ant species were found to consume only Anoplotermes-group termites, indicating possible predatory specialisation at a higher taxonomic level. Using a laboratory feeding test, we were able to detect termite COII sequences in ant guts up to 2 h after feeding, indicating that our method only detects recent feeding events. Our data provide tentative support for the hypothesis that unspecialised termite predation by ants is widespread and highlight the use of molecular approaches for future studies of ant-termite food webs.

  14. The Revised Test of Visual-Motor Integration: Its Relation to the Test of Visual-Motor Integration and Bender Visual-Motor Gestalt Test for Regular Education Students.

    Science.gov (United States)

    Siewert, Julaine C.; Breen, Michael J.

    1983-01-01

    Compared three tests of visual-motor integration: The Revised Test of Visual-Motor Integration (VMI-R), the Test of Visual-Motor Integration (VMI), and the Bender Visual-Motor Gestalt Test (BG). Results showed significantly higher BG age equivalent scores. Highly significant correlations were found among all variables. (WAS)

  15. 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.

  16. 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...

  17. Moribund Ants Do Not Call for Help.

    Directory of Open Access Journals (Sweden)

    Krzysztof Miler

    Full Text Available When an antlion captures a foraging ant, the victim's nestmates may display rescue behaviour. This study tested the hypothesis that the expression of rescue behaviour depends on the life expectancy of the captured ant. This hypothesis predicts that the expression of rescue behaviour will be less frequent when the captured ant has a lower life expectancy than when it has a higher life expectancy because such a response would be adaptive at the colony level. Indeed, significant differences were found in the frequency of rescue behaviours in response to antlion victims with differing life expectancies. In agreement with prediction, victims with lower life expectancies were rescued less frequently, and those rescues had a longer latency and shorter duration. There was also a qualitative difference in the behaviour of rescuers to victims from the low and high life expectancy groups. Several explanations for these findings are proposed.

  18. Hopfield neural network based on ant system

    Institute of Scientific and Technical Information of China (English)

    洪炳镕; 金飞虎; 郭琦

    2004-01-01

    Hopfield neural network is a single layer feedforward neural network. Hopfield network requires some control parameters to be carefully selected, else the network is apt to converge to local minimum. An ant system is a nature inspired meta heuristic algorithm. It has been applied to several combinatorial optimization problems such as Traveling Salesman Problem, Scheduling Problems, etc. This paper will show an ant system may be used in tuning the network control parameters by a group of cooperated ants. The major advantage of this network is to adjust the network parameters automatically, avoiding a blind search for the set of control parameters.This network was tested on two TSP problems, 5 cities and 10 cities. The results have shown an obvious improvement.

  19. 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.

  20. An ants-eye view of an ant-plant protection mutualism

    Science.gov (United States)

    Lanan, M. C.; Bronstein, J. L.

    2013-01-01

    Ant protection of extrafloral nectar-secreting plants (EFN plants) is a common form of mutualism found in most habitats around the world. However, very few studies have considered these mutualisms from the ant, rather than the plant, perspective. In particular, a whole-colony perspective that takes into account the spatial structure and nest arrangement of the ant colonies that visit these plants has been lacking, obscuring when and how colony-level foraging decisions might affect tending rates on individual plants. Here, we experimentally demonstrate that recruitment of Crematogaster opuntiae (Buren) ant workers to the extrafloral nectar-secreting cactus Ferocactus wislizeni (Englem) is not independent between plants up to 5m apart. Colony territories of C. opuntiae are large, covering areas of up to 5000m2, and workers visit between five and thirty-four extrafloral nectar-secreting barrel cacti within the territories. These ants are highly polydomous, with up to twenty nest entrances dispersed throughout the territory and interconnected by trail networks. Our study demonstrates that worker recruitment is not independent within large polydomous ant colonies, highlighting the importance of considering colonies rather than individual workers as the relevant study unit within ant/plant protection mutualisms PMID:23515612

  1. The worldwide expansion of the Argentine ant

    DEFF Research Database (Denmark)

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

    2010-01-01

    DNA haplotypes also suggests that supercolonies in the introduced range each derive from a single source supercolony and that one of these source supercolonies has been particularly successful, being the basis of many introduced populations spread across the world. Comparison of the genetic diversity......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...... to possible strategies to be used to control invasive ants....

  2. The ejaculatory biology of leafcutter ants

    DEFF Research Database (Denmark)

    den Boer, Susanne; Stürup, Marlene; Boomsma, Jacobus Jan

    2015-01-01

    The eusocial ants are unique in that females (queens) acquire and store sperm on a single mating flight early in adult life. This event largely determines the size (possibly millions of workers), longevity (possibly decades) and genetic variation of the colonies that queens found, but our...... understanding of the fundamental biology of ejaculate production, transfer and physiological function remains extremely limited. We studied the ejaculation process in the leafcutter ant Atta colombica and found that it starts with the appearance of a clear pre-ejaculatory fluid (PEF) at the tip...

  3. Chaotic ant swarm optimization to economic dispatch

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Jiejin; Ma, Xiaoqian [Electric Power College, South China University of Technology, Guangzhou 510640 (China); Li, Lixiang; Yang, Yixian [Information Security Center, Department of Information Engineering, Beijing University of Posts and Telecommunications, Beijing 100876 (China); State Key Laboratory of Networking and Switching, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Peng, Haipeng [Information Security Center, Department of Information Engineering, Beijing University of Posts and Telecommunications, Beijing 100876 (China); State Key Laboratory of Networking and Switching, Beijing University of Posts and Telecommunications, Beijing 100876 (China); School of Information Science and Engineering, Shenyang University of Technology, Shenyang 110023 (China); Wang, Xiangdong [School of Information Science and Engineering, Shenyang University of Technology, Shenyang 110023 (China)

    2007-08-15

    This paper developed a novel algorithm named chaotic ant swarm optimization (CASO) for solving the economic dispatch (ED) problems of thermal generators in power systems. This algorithm combines with the chaotic and self-organization behavior of ants in the foraging process. It includes both effects of chaotic dynamics and swarm-based search. The algorithm was employed to solve the ED problems of thermal generators. The proposed method was applied to three examples of power systems. Simulation results demonstrated that the method can obtain feasible and effective solutions, and it is a promising alternative approach for solving the ED problems in practical power systems. (author)

  4. Ant functional responses along environmental gradients.

    Science.gov (United States)

    Arnan, Xavier; Cerdá, Xim; Retana, Javier

    2014-11-01

    Understanding species distributions and diversity gradients is a central challenge in ecology and requires prior knowledge of the functional traits mediating species' survival under particular environmental conditions. While the functional ecology of plants has been reasonably well explored, much less is known about that of animals. Ants are among the most diverse, abundant and ecologically significant organisms on earth, and they perform a great variety of ecological functions. In this study, we analyse how the functional species traits present in ant communities vary along broad gradients in climate, productivity and vegetation type in the south-western Mediterranean. To this end, we compiled one of the largest animal databases to date: it contains information on 211 local ant communities (including eight climate variables, productivity, and vegetation type) and 124 ant species, for which 10 functional traits are described. We used traits that characterize different dimensions of the ant functional niche with respect to morphology, life history and behaviour at both individual and colony level. We calculated two complementary functional trait community indices ('trait average' and 'trait dissimilarity') for each trait, and we analysed how they varied along the three different gradients using generalized least squares models that accounted for spatial autocorrelation. Our results show that productivity, vegetation type and, to a lesser extent, each climate variable per se might play an important role in shaping the occurrence of functional species traits in ant communities. Among the climate variables, temperature and precipitation seasonality had a much higher influence on functional responses than their mean values, whose effects were almost lacking. Our results suggest that strong relationships might exist between the abiotic environment and the distribution of functional traits among south-western Mediterranean ant communities. This finding indicates that

  5. Ant parasite queens revert to mating singly

    DEFF Research Database (Denmark)

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

    2004-01-01

    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...... 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...

  6. 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......, indirectly, on fungal enzymes to break down the plant material brought in by the ants as fungal substrate. The more than 210 extant fungus-growing ant species differ considerably in colony size, social complexity and substrate-use. Only the derived leaf-cutting ants are specialized on using fresh leaves...... enzyme activity across ant genera could indeed be partially explained by substrate differences. This implies that fungal enzyme activity has likely coevolved with the genus- or species-specific substrates that the ants use to manure their fungus garden. Plant decomposing enzymes are thus not only...

  7. Variation in Extrafloral Nectary Productivity Influences the Ant Foraging.

    Science.gov (United States)

    Lange, Denise; Calixto, Eduardo Soares; Del-Claro, Kleber

    2017-01-01

    Extrafloral nectar is the main food source offered by plants to predatory ants in most land environments. Although many studies have demonstrated the importance of extrafloral nectaries (EFNs) to plant defense against herbivores, the influence of EFNs secretory activity pattern on predatory ants remains yet not fully understood. Here, we verified the relation between the extrafloral nectar production of a plant community in Cerrado in different times of the day, and its attractiveness to ants. The extrafloral nectaries (EFNs) of seven plant species showed higher productivity overnight. Ant abundance was higher in times of large extrafloral nectar production, however, there was no positive relation between ant richness on plants and EFNs productivity. There was temporal resource partitioning among ant species, and it indicates strong resource competition. The nectar productivity varied among plant species and time of the day, and it influenced the visitation patterns of ants. Therefore, EFNs are a key ant-plant interaction driver in the studied system.

  8. Variation in Extrafloral Nectary Productivity Influences the Ant Foraging

    Science.gov (United States)

    2017-01-01

    Extrafloral nectar is the main food source offered by plants to predatory ants in most land environments. Although many studies have demonstrated the importance of extrafloral nectaries (EFNs) to plant defense against herbivores, the influence of EFNs secretory activity pattern on predatory ants remains yet not fully understood. Here, we verified the relation between the extrafloral nectar production of a plant community in Cerrado in different times of the day, and its attractiveness to ants. The extrafloral nectaries (EFNs) of seven plant species showed higher productivity overnight. Ant abundance was higher in times of large extrafloral nectar production, however, there was no positive relation between ant richness on plants and EFNs productivity. There was temporal resource partitioning among ant species, and it indicates strong resource competition. The nectar productivity varied among plant species and time of the day, and it influenced the visitation patterns of ants. Therefore, EFNs are a key ant-plant interaction driver in the studied system. PMID:28046069

  9. Research on the Perceptual Law of Artificial Ants

    Institute of Scientific and Technical Information of China (English)

    ZHENG Zhaobao

    2005-01-01

    Beginning with the analysis of the behavior of natural ants, this paper illuminates the principle and method that, by adopting image texture energy as pheromone and finding their way on the track of the pheromone, artificial ants have the ability to identify and remember through similar measurement of pheromone. Based on the quantity of experiments, this paper analyzes some factors that influence the ability of artificial ants and draws some conclusions about the law of ant perception.

  10. 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....

  11. 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.

  12. 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

  13. Eavesdropping on cooperative communication within an ant-butterfly mutualism

    DEFF Research Database (Denmark)

    Elgar, Mark A.; Nash, David Richard; Pierce, Naomi E.

    2016-01-01

    of the Australian lycaenid butterfly, Jalmenus evagoras, form an obligate association with several species of attendant ants, including Iridomyrmex mayri. Ants protect the caterpillars and pupae, and in return are rewarded with nutritious secretions. Female and male adult butterflies use ants as signals...

  14. Ant-egg cataract. An electron microscopic study

    DEFF Research Database (Denmark)

    Schrøder, H D; Nissen, S H

    1979-01-01

    The ultrastructure of the ant-egg cataractous lens has been studied. Comparison of tissue demineralized by means of EDTA with untreated tissue showed the calcium salts in the ant-eggs to be mostly crystalline. A laminar appearance of the ant-egg seen in EDTA treated material suggested an intermit...

  15. 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.

  16. Mutualistic ants as an indirect defence against leaf pathogens.

    Science.gov (United States)

    González-Teuber, Marcia; Kaltenpoth, Martin; Boland, Wilhelm

    2014-04-01

    Mutualistic ants are commonly considered as an efficient indirect defence against herbivores. Nevertheless, their indirect protective role against plant pathogens has been scarcely investigated. We compared the protective role against pathogens of two different ant partners, a mutualistic and a parasitic ant, on the host plant Acacia hindsii (Fabaceae). The epiphytic bacterial community on leaves was evaluated in the presence and absence of both ant partners by cultivation and by 454 pyrosequencing of the 16S rRNA gene. Pathogen-inflicted leaf damage, epiphytic bacterial abundance (colony-forming units) and number of operational taxonomic units (OTUs) were significantly higher in plants inhabited by parasitic ants than in plants inhabited by mutualistic ants. Unifrac unweighted and weighted principal component analyses showed that the bacterial community composition on leaves changed significantly when mutualistic ants were removed from plants or when plants were inhabited by parasitic ants. Direct mechanisms provided by ant-associated bacteria would contribute to the protective role against pathogens. The results suggest that the indirect defence of mutualistic ants also covers the protection from bacterial plant pathogens. Our findings highlight the importance of considering bacterial partners in ant-plant defensive mutualisms, which can contribute significantly to ant-mediated protection from plant pathogens. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  17. 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

  18. 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

    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......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...... 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...

  19. Vestlus päevapoliitikast Ants Vahtrasega / Ants Vahtras ; interv. Hillar Padu

    Index Scriptorium Estoniae

    Vahtras, Ants, 1953-

    2001-01-01

    Keskerakonna Hiiumaa osakonna esimees Ants Vahtras keskendub vestluses Keskerakonna kandidaatidele presidendi valimistele, arutleb presidendile vajalike isikuomaduste, haldusreformi, Hiiumaa Suurkogu, erastamiselt laekuva raha kasutamise üle ning annab hinnangu kultuuripoliitikale. Autor: Keskerakond

  20. Nõunik Ants Laansalu - rohkem talupoeg kui sulane / Ants Laansalu ; interv. Heiki Raudla

    Index Scriptorium Estoniae

    Laansalu, Ants, 1938-2011

    2008-01-01

    Intervjuu põllumajandusministeeriumi nõunikuga, kes vastab küsimustele, mis puudutavad Eesti põllumajandusministreid, põllumehe mainet, põllumajanduse tulevikku Eestis ja maailmas. Vt. samas: Ants Laansalu: CV

  1. Ants ja Jaak / Ants Juske, Jaak Juske ; intervjueerinud Margit Tõnson, Maris Sander

    Index Scriptorium Estoniae

    Juske, Ants, 1956-

    2011-01-01

    Kunstiteadlane Ants Juske ja tema poliitikust poeg Jaak Juske räägivad põlvkondade erinevustest ja konfliktidest, oma poliitilisest identiteedist, haridusest, eeskujudest, huvidest, eluviisidest. Nende eluloolisi andmeid

  2. Ants Veetõusme ja tema valikud / Ants Veetõusme ; interv. Imbi E. Kaljuste

    Index Scriptorium Estoniae

    Veetõusme, Ants, 1949-

    2002-01-01

    Eesti Maksumaksjate Liidu juhatuse esimehe Ants Veetõusme varasemast elust ning praegusest tegevusest EML-i juhi, spordijuhi ja FIE-na. Kommenteerivad Tõnu Anton ja Tiit Nuudi. Tartu linnapea 1991-1993

  3. The worldwide expansion of the Argentine ant

    DEFF Research Database (Denmark)

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

    2010-01-01

    ) 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...

  4. 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.

  5. The evolution of invasiveness in garden ants

    DEFF Research Database (Denmark)

    Cremer, Sylvia; Ugelvig, Line Vej; Drijfhout, Falko P

    2008-01-01

    It is unclear why some species become successful invaders whilst others fail, and whether invasive success depends on pre-adaptations already present in the native range or on characters evolving de-novo after introduction. Ants are among the worst invasive pests, with Lasius neglectus and its ra...

  6. Recognition of social identity in ants

    DEFF Research Database (Denmark)

    Bos, Nick; d'Ettorre, Patrizia

    2012-01-01

    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...

  7. 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......, the DHQs were accompanied by six histrionicotoxins (HTXs), viz., 283A, 285A, 285B, 285C, 287A, and 287D. This co-occurrence of the HTX and DHQ alkaloids is the usual pattern seen in dendrobatid frogs. This finding contrasts with our earlier study, where workers of a Brazilian ant, Solenopsis (Diplorhoptrum......) 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...

  8. Improving Emergency Management by Modeling Ant Colonies

    Science.gov (United States)

    2015-03-01

    brood. The brood stages include the egg, the larval, and the pupa.27 The brood is dependent on the colony for nourishment and warmth until fully...night for rest and to relocate the colony. The bivouac is what is created when army ants huddle together in a ball instead of building a physical nest

  9. The ejaculatory biology of leafcutter ants

    DEFF Research Database (Denmark)

    den Boer, Susanne; Stürup, Marlene; Boomsma, Jacobus Jan

    2015-01-01

    understanding of the fundamental biology of ejaculate production, transfer and physiological function remains extremely limited. We studied the ejaculation process in the leafcutter ant Atta colombica and found that it starts with the appearance of a clear pre-ejaculatory fluid (PEF) at the tip...

  10. La nueva novela hispanoamericana ante Europa

    Directory of Open Access Journals (Sweden)

    Manuel Zapata Olivella

    1964-01-01

    Full Text Available Hace exactamente medio siglo -1905- Unamuno se burlaba de los escritores hispanoamericanos a quienes consumía el antojo de descubrir a Europa a los europeos en vez de describir lo que tenían ante sus ojos.

  11. 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

    2009-07-01

    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.

  12. Caste-specific tyramides from Myrmicine ants

    Science.gov (United States)

    T.H. Jones; H.M. Garrafo; T.F. Spande; N.R. Andriamaharavo; J.S.T. Gorman; A.J. Snyder; A.W. Jeter; J.A. Torres; John W. Daly

    2010-01-01

    Analysis of the extracts of male ants of Monomorium minimum and Monomorium ebeninum by GC-MS and GC-FTIR revealed the presence of tyramides 2 and 4c, for which the structures were established by comparison with synthetic samples. These compounds and their analogues 1 and 3 were also found in males of other Monomorium species, males of Myrmicaria opaciventris, and males...

  13. Ant System Algorithm Research and Its Applications

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this paper, systematic review on Ant System (AS) algorithm research and application is made, and the authors works of introducing As algorithm into continuous space application are summarized. Then the applicability characters of AS in continuous space optimization problems are also discussed.

  14. Enhanced Pest Ant Control with Hydrophobic Bait

    Science.gov (United States)

    Ants occupy every ecological niche in the world where they contribute to the ecosystem, e.g., as scavengers and aerators of the soil. However, when they are transported, usually through human activities, to new locations they have powerful negative impacts on their adopted homeland. Five of the 17 l...

  15. Ants mediate the structure of phytotelm communities in an ant-garden bromeliad

    OpenAIRE

    Céréghino, Régis; Leroy, Céline; Dejean,Alain; Corbara, Bruno

    2010-01-01

    International audience; The main theories explaining the biological diversity of rain forests often confer a limited understanding of the contribution of interspecific interactions to the observed patterns. We show how two-species mutualisms can affect much larger segments of the invertebrate community in tropical rain forests. Aechmea mertensii (Bromeliaceae) is both a phytotelm (plant-held water) and an ant-garden epiphyte. We studied the influence of its associated ant species (Pachycondyl...

  16. Can the Argentine ant ( Linepithema humile Mayr) replace native ants in myrmecochory?

    Science.gov (United States)

    Gómez, Crisanto; Oliveras, Jordi

    2003-04-01

    We analyse the influence of the Argentine ant ( Linepithema humile Mayr) on the seed dispersal process of the myrmecochorous plants Euphorbia characias, E. biumbellata, Genista linifolia, G. triflora, G. monspessulana and Sarothamnus arboreus. The observations were made in two study plots of Mediterranean cork-oak secondary forest (invaded and non-invaded by L. humile). The presence of L. humile implies the displacement of all native ant species that disperse seeds. Seed transports in the non-invaded zone were carried out by eight ant species. In the invaded zone, L. humile workers removed and transported seeds to the nest. In vertebrate exclusion trials, we observed the same level of seed removal in the invaded and non-invaded zones. Two findings could explain this result. Although mean time to seed localization was higher for native ants (431.7 s) than that for L. humile (150.5 s), the mean proportion of seeds transported after being detected was higher (50.1%) in non-invaded than in invaded (16.8%) zones. The proportion of seeds removed and transported into an ant nest after an ant-seed interaction had dramatically reduced from non-invaded (41.9%) to invaded (7.4%) zones. The levels of seed dispersal by ants found prior to invasion are unlikely to be maintained in invaded zones. However, total replacement of seed dispersal function is possible if contact iteration finally offers similar levels or quantities of seeds reaching the nests. The results obtained confirm that the Argentine ant invasion may affect myrmecochory dramatically in the Mediterranean biome.

  17. Absolute energy measurement of the electron beam of TJNAF (hall A) by p(e,e`p) elastic scattering; Mesure absolue de l`energie du faisceau d`electrons de TJNAF (hall A) par diffusion elastique p(e,e`p)

    Energy Technology Data Exchange (ETDEWEB)

    Ravel, Olivier [Ecole Doctorale des Science Fondamentales, Universite Blaise Pascal, U.F.R. de Recherche Scientifique et Technique, F-63177 Aubiere Cedex (France)

    1997-11-21

    This thesis describes the electron beam energy measurement device at TJNAF hall A (Virginia USA). The accuracy of the measurement is 10{sup -4}. Such an accuracy is needed for scattering electron experiments, in particular for the determination of cross section by transverse-longitudinal separation. The method is based on the measurements of the scattering particle angles of the reaction p(e,e`p). Angular measurements are realized by a setup of silicon micro-strips detectors with an angular accuracy of 10{mu}rd. Theoretical aspects of the method and some techniques of electron beam energy measurement are presented. A precise uncertainty calculation allowed to determine the EP detector characteristics: thin target of polypropylene, silicon strips detectors, data acquisition, electronics and trigger. The high level of accuracy leads to the development of a new and original techniques of position measurement. The data analysis method, the beam energy calculation and the different corrections (vertex, radiative tails) are presented. The first tests of the detector are reviewed. The first measurement of TJNAF electron beam energy with the EP detector is foreseen on March 1998. (author) 43 refs., 84 figs., 32 tabs.

  18. Parameters of ante-mortem delirium

    Directory of Open Access Journals (Sweden)

    Deksnyte, Aušra

    2014-02-01

    Full Text Available Objectives. The aim of this study was to investigate the parameters of ante-mortem delirium of the patients in a closed psychiatric institution and to compare them with the ante-mortem psychopathology of the medical patients. Methods. There were 139 medical records of the patients analyzed, who died during the period of 1997-2003 at the in-patient psychiatric institution. The diagnoses were recorded according to the International Classification of Diseases, 10th Revision (ICD-10 criteria. Patients’ data included age, gender, previous psychiatric disorders, current somatic and psychiatric morbidity, and comorbidity. Results. The incidence of delirium was 83,7%. The delirium group included more elder, male persons who were more likely to have dementia and less inclined to depression. Surprisingly the incidence of delirium among non-dementia men was quite high – 76,9%, as compared to non-dementia women – 23,1% (P=0,008. The duration of delirium differed from 1 to 1335 days. Longer delirium was observed among elder than 75 years (87,7, SD 183,9 vs52,6, SD 121,4 days; P=0,019 and dementia (83,6, SD 173,6 vs 13,5, SD 11,6 days; P<0,001 patients, but did not differ in gender groups. Conclusions. Ante-mortem delirium occurred more commonly in more elder and demented patients The duration of ante-mortem delirium was shorter in younger and non-dementia patients. Patients of the psychiatric institution tend to have longer deliriums than medical patients. The patients with depression and the history of alcohol abuse were not likely to get ante-mortem delirium. Before death in many persons hyperactive and mixed delirium transformed into hypoactive.

  19. 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

  20. Dead ant walking: a myrmecophilous beetle predator uses parasitoid host location cues to selectively prey on parasitized ants.

    Science.gov (United States)

    Mathis, Kaitlyn A; Tsutsui, Neil D

    2016-08-17

    Myrmecophiles (i.e. organisms that associate with ants) use a variety of ecological niches and employ different strategies to survive encounters with ants. Because ants are typically excellent defenders, myrmecophiles may choose moments of weakness to take advantage of their ant associates. This hypothesis was studied in the rove beetle, Myrmedonota xipe, which associates with Azteca sericeasur ants in the presence of parasitoid flies. A combination of laboratory and field experiments show that M. xipe beetles selectively locate and prey upon parasitized ants. These parasitized ants are less aggressive towards beetles than healthy ants, allowing beetles to eat the parasitized ants alive without interruption. Moreover, behavioural assays and chemical analysis reveal that M. xipe are attracted to the ant's alarm pheromone, the same secretion used by the phorid fly parasitoids in host location. This strategy allows beetles access to an abundant but otherwise inaccessible resource, as A. sericeasur ants are typically highly aggressive. These results are the first, to our knowledge, to demonstrate a predator sharing cues with a parasitoid to gain access to an otherwise unavailable prey item. Furthermore, this work highlights the importance of studying ant-myrmecophile interactions beyond just their pairwise context.

  1. Experimental Study of the Dynamics of Foraging Ants

    Science.gov (United States)

    Walker, J. I.; Fetzner, R. P.; Baxter, G. W.

    2006-03-01

    We study the search paths of foraging ants in order to describe their behavior mathematically. Ants have become popular as simple agents in models of artificial life. Here, the ant is presented the problem of finding food when no food cues are present. In this experiment, individual ants (Formicinae lasius flavus) are allowed to forage on a two-dimensional textured surface in the absence of a food source. The position of the ant as a function of time is determined with a high resolution digital camera. The scaling properties of the resulting foraging paths compare favorably with those of certain types of random walk.

  2. 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.

  3. The interactions of ants with their biotic environment

    Science.gov (United States)

    Renner, Susanne S.

    2017-01-01

    This special 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 special 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. PMID:28298352

  4. 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.

  5. Relación entre maduración, sexo y nivel socio-económico a través del Test Guestaltico Visomotor de Bender

    OpenAIRE

    Matilde Ráez de Ramírez; Cecilia Thome; Patricia Martinez; Isabel Niño de Guzmán; Zoila Rossel; Walter Twanama

    1986-01-01

    En el presente trabajo se investiga la relación entre edad, sexo y nivel socio- económico en 1,019 niños de 5 años a 10 años, 11 meses a través del Test Guestáltico Visomotor de Bender, utilizándose los criterios de corrección de Koppitz. No se encontró diferencias significativas de acuerdo al sexo o nivel socio-económico. Al comparar los resultados de la muestra con los de Koppitz encontramos diferencias significativas para 8 de los 12 grupos estudiados. Así mismo se comprobó que la prueba s...

  6. Relación entre maduración, sexo y nivel socio-económico a través del Test Guestaltico Visomotor de Bender

    Directory of Open Access Journals (Sweden)

    Matilde Ráez de Ramírez

    1986-06-01

    Full Text Available En el presente trabajo se investiga la relación entre edad, sexo y nivel socio- económico en 1,019 niños de 5 años a 10 años, 11 meses a través del Test Guestáltico Visomotor de Bender, utilizándose los criterios de corrección de Koppitz. No se encontró diferencias significativas de acuerdo al sexo o nivel socio-económico. Al comparar los resultados de la muestra con los de Koppitz encontramos diferencias significativas para 8 de los 12 grupos estudiados. Así mismo se comprobó que la prueba sólo es evolutiva hasta los 9 años, tal como lo señala Taylor y col.

  7. Padronização brasileira do Teste Bender Koppitz-2 em crianças da cidade de São Paulo

    OpenAIRE

    Cristiano Esteves

    2015-01-01

    O Teste Guestáltico Visomotor de Bender é um teste psicológico utilizado em psicodiagnósticos infantis nas áreas clínica e neuropsicológica, embora existam adaptações para adolescentes e adultos. Em crianças seu uso se destina a avaliações da maturidade percepto-motora ou organização visomotora, diagnósticos de lesões cerebrais e perturbações emocionais, podendo também ser utilizado como uma técnica projetiva. Para os adultos é empregado tanto como uma técnica projetiva quanto para a identifi...

  8. 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.

  9. Insect navigation: do ants live in the now?

    Science.gov (United States)

    Graham, Paul; Mangan, Michael

    2015-03-01

    Visual navigation is a critical behaviour for many animals, and it has been particularly well studied in ants. Decades of ant navigation research have uncovered many ways in which efficient navigation can be implemented in small brains. For example, ants show us how visual information can drive navigation via procedural rather than map-like instructions. Two recent behavioural observations highlight interesting adaptive ways in which ants implement visual guidance. Firstly, it has been shown that the systematic nest searches of ants can be biased by recent experience of familiar scenes. Secondly, ants have been observed to show temporary periods of confusion when asked to repeat a route segment, even if that route segment is very familiar. Taken together, these results indicate that the navigational decisions of ants take into account their recent experiences as well as the currently perceived environment. © 2015. Published by The Company of Biologists Ltd.

  10. Extrafloral nectar content alters foraging preferences of a predatory ant.

    Science.gov (United States)

    Wilder, Shawn M; Eubanks, Micky D

    2010-04-23

    We tested whether the carbohydrate and amino acid content of extrafloral nectar affected prey choice by a predatory ant. Fire ants, Solenopsis invicta, were provided with artificial nectar that varied in the presence of carbohydrates and amino acids and were then provided with two prey items that differed in nutritional content, female and male crickets. Colonies of fire ants provided with carbohydrate supplements consumed less of the female crickets and frequently did not consume the high-lipid ovaries of female crickets. Colonies of fire ants provided with amino acid supplements consumed less of the male crickets. While a number of studies have shown that the presence of extrafloral nectar or honeydew can affect ant foraging activity, these results suggest that the nutritional composition of extrafloral nectar is also important and can affect subsequent prey choice by predatory ants. Our results suggest that, by altering the composition of extrafloral nectar, plants could manipulate the prey preferences of ants foraging on them.

  11. 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. PMID:23967129

  12. 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.

  13. Bioturbation by Fire Ants in the Coastal Prairie of Texas

    Science.gov (United States)

    Cameron, G.; Williams, L.

    2001-12-01

    Fire ants (Solenopsis invicta) were introduced to the US in the early part of the last century. They have spread throughout the southeastern US in the absence of native competitors and predators with a range limited by abiotic factors. Each fire ant mound contains thousands of individuals, can be large, and can be numerous enough to comprise a dominant feature of the landscape. Studies of this species have focused upon its spread, formation of single- and multiple-queen colonies, genetic structure, and impact on native fauna and human health. Some studies have analyzed native fire ant-soil interactions, but few studies have examined the process of bioturbation by introduced fire ants in native ecosystems. Fire ants on the coastal prairie of Texas primarily are of the multiple-queen type that exhibit a much higher density of mounds than the single-queen type. Consequently, mound-building activities by fire ants can have a marked effect upon soil structure and nutrient content and may affect soil organisms and plants. Fire ant activity, mound density, mound dispersion, soil texture, soil permeability, soil moisture content, and soil nutrients were measured. Fire ants mounds are visible aboveground from April-November. Density of mounds was 117-738/ha, and average mound lifespan was 3.6 months with only 9% of the mounds remaining active throughout the entire season. Mounds were dispersed randomly. Foraging activity by fire ants was from June through October with a peak in July. Annual soil turnover was estimated by collecting and weighing mounds. There was no effect of ant mounds on soil texture, but water infiltration was higher in areas with ant mounds. Early-season samples showed no nutrient differences, but late-season samples showed that ant mounds contained higher amounts of micronutrients than random samples of soil. These data are compared to similar data on effects of mounds from native ants and from native and introduced ants in different habitats.

  14. Honey Bees Avoiding Ant Harassment at Flowers Using Scent Cues.

    Science.gov (United States)

    Sidhu, Sheena C; Wilson Rankin, Erin E

    2016-02-01

    Pollinators require resources throughout the year to maintain healthy populations. Along the urban-natural interface, floral resource availability may be limited especially when the system experiences extreme drought and fire threats. In such areas, succulents, such as Aloe spp., are commonly planted to serve as functional drought-tolerant, fire-protective landscaping, which can also support pollinator populations. However, access to this resource may be restricted by competition from other floral foragers, including invasive pests. We measured free-foraging honey bee (Apis mellifera L.) visitation rate and visitation duration to aloe flowers with and without Argentine ants (Linepithema humile (Mayr)) in a drought-stressed environment and found that bees actively avoided foraging on the ant-occupied flowers. To determine the mechanisms of avoidance, our subsequent experiments assessed visitation in the absence of ants and compared aloe flowers treated with ant pheromone to unmanipulated flowers lacking ant pheromone. Bees approached all flowers equally, but accepted flowers without ants at a higher rate than flowers with ants. Visitation duration also increased twofold on ant-excluded flowers, which suggests that Argentine ants may limit resource acquisition by bees. Honey bees similarly avoided flowers with Argentine ant pheromone and preferentially visited unmanipulated flowers at threefold higher rate. This study demonstrates that honey bees avoid foraging on floral resources with invasive Argentine ants and that bees use ant odors to avoid ant-occupied flowers. Resource limitation by this invasive pest ant may have serious implication for sustaining healthy pollinator populations at the urban-natural interface. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. 基于奔德斯算法的安全约束机组组合方法%A Method for Security Constrained Unit Commitment Based on Benders Algorithm

    Institute of Scientific and Technical Information of China (English)

    王楠; 张粒子; 袁喆; 张黎明; 李雪

    2012-01-01

    When security-constrained unit commitment (SCUC) was directly solved by mixed integer programming algorithm, the calculation efficiency would considerably decrease, and when SCUC was solved by Benders algorithm, it led to the problem that the solution efficiency would decrease due to the algorithm shock and the restriction of system scale. A new Benders algorithm-based method to solve SCUC was proposed. Based on Benders algorithm, by means of adding the link to correct the constraint of out-of-limit after the iteration of Benders master problem, the search direction of Benders cut could be controlled; by means of adding the link to identify taken-effect constraints the search space of Benders algorithm was reduced, thus the solution efficiency of SCUC optimization could be improved. The effectiveness of the proposed method was verified by simulation results of 6-machine 3-bus system and 54-machine 118-bus system.%针对采用混合整数规划算法直接求解安全约束机组组合,将使计算效率大幅度降低,而利用奔德斯算法求解则存在着算法振荡和受系统规模制约求解效率下降的问题,提出了一种基于奔德斯算法的安全约束机组组合新方法.该方法在奔德斯算法的基础上,通过纳入新增越限约束校正环节,控制了奔德斯割的寻优方向,通过增加起作用约束识别环节,缩小了奔德斯算法的寻优空间,进而提高了安全约束机组组合优化问题的求解效率.6机3节点和54机118节点算例验证了所提方法的有效性.

  16. Interaction between Mutualisms: Ant-tended butterflies exploit enemy-free space provided by ant-treehopper associations.

    Science.gov (United States)

    Kaminski, Lucas A; Freitas, André V L; Oliveira, Paulo S

    2010-09-01

    Although mutualisms have been intensively investigated, demonstration of indirect effects between co-occurring mutualistic systems is rare. For instance, the ecological consequences of co-occurrence of ant-tended insects on a plant have never been examined for survival effects on either trophobiont species. Here, we assess the selective pressures mediating co-occurrence of a facultative ant-tended butterfly (Parrhasius polibetes) with ant-tended treehoppers (Guayaquila xiphias) on Schefflera vinosa shrubs. We evaluated host plant selection and caterpillar survival in P. polibetes in the presence and absence of ant-treehopper associations. Paired trials revealed that butterflies preferably oviposit on branches hosting ant-tended treehoppers when they had a choice between those and branches without this interaction. Presence of ant-tended treehoppers on a branch reduced the abundance of P. polibetes' natural enemies and improved caterpillar survival in both premyrmecophylic and ant-tended phases. Thus ant-tended treehoppers create an enemy-free space on foliage that butterflies exploit to protect larval offspring. These findings connect two widely documented ant-trophobiont mutualisms and highlight the importance of considering multiple interactions for a proper understanding of ant-plant-herbivore systems. Detection of other ant-based mutualisms on oviposition to improve offspring survival may have represented an important evolutionary step in the process of host plant selection in facultative myrmecophilous butterflies.

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

    Science.gov (United States)

    Stuble, Katharine L; Kirkman, L Katherine; Carroll, C Ronald; Sanders, Nathan J

    2011-06-01

    The degree to which changes in community composition mediate the probability of colonization and spread of non-native species is not well understood, especially in animal communities. High species richness may hinder the establishment of non-native species. Distinguishing between this scenario 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 and fire ants in four experimental plots. We then observed the reassembly and reestablishment of the ants in these plots for 1 year after treatment. The abundance of fire ants in treated plots did not differ from abundance in control plots 1 year after treatment. Likewise, 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 and fire ants to disturbance can be comparable.

  18. Ant foraging on extrafloral nectaries of Qualea grandiflora (Vochysiaceae) in cerrado vegetation: ants as potential antiherbivore agents.

    Science.gov (United States)

    Oliveira, P S; da Silva, A F; Martins, A B

    1987-12-01

    Qualea grandiflora is a typical tree of Brazilian cerrados (savanna-like vegetation) that bears paired extrafloral nectaries (EFNs) along its stems. Results show that possession of EFNs increases ant density on Q. grandiflora shrubs over that of neighbouring non-nectariferous plants. Frequency of ant occupancy and mean number of ants per plant were much higher on Qualea than on plants lacking EFNs. These differences resulted in many more live termitebaits being attacked by foraging ants on Qualea than on neighbours without EFNs. Termites were attacked in equal numbers and with equal speeds on different-aged leaves of Qualea. The greatest potential for herbivore deterrence was presented by Camponotus ants (C. crassus, C. rufipes and C. aff. blandus), which together attacked significantly more termites than nine other ant species grouped. EFNs are regarded as important promoters of ant activity on cerado plants.

  19. A plant needs ants like a dog needs fleas: Myrmelachista schumanni ants gall many tree species to create housing.

    Science.gov (United States)

    Edwards, David P; Frederickson, Megan E; Shepard, Glenn H; Yu, Douglas W

    2009-11-01

    Hundreds of tropical plant species house ant colonies in specialized chambers called domatia. When, in 1873, Richard Spruce likened plant-ants to fleas and asserted that domatia are ant-created galls, he incited a debate that lasted almost a century. Although we now know that domatia are not galls and that most ant-plant interactions are mutualisms and not parasitisms, we revisit Spruce's suggestion that ants can gall in light of our observations of the plant-ant Myrmelachista schumanni, which creates clearings in the Amazonian rain forest called "supay-chakras," or "devil's gardens." We observed swollen scars on the trunks of nonmyrmecophytic canopy trees surrounding supay-chakras, and within these swellings, we found networks of cavities inhabited by M. schumanni. Here, we summarize the evidence supporting the hypothesis that M. schumanni ants make these galls, and we hypothesize that the adaptive benefit of galling is to increase the amount of nesting space available to M. schumanni colonies.

  20. Fender Bender Physics.

    Science.gov (United States)

    Bevin, Roy Q.; Raudebaugh, Robert A.

    This book is based on an integrated approach to science and technology and targets middle schools students. Each unit includes a teacher's guide and eight science activities. Units include: (1) "The Mousetrap Car"; (2) "The CO2 Car"; and (3) "The Space Frame Vehicle". Supplemental materials consist of seven readings including: (1) "Brainstorming";…

  1. Mathematical mind-benders

    CERN Document Server

    Winkler, Peter

    2007-01-01

    Peter Winkler is at it again. Following the enthusiastic reaction to Mathematical Puzzles: A Connoisseur's Collection, Peter has compiled a new collection of elegant mathematical puzzles to challenge and entertain the reader. The original puzzle connoisseur shares these puzzles, old and new, so that you can add them to your own anthology. This book is for lovers of mathematics, lovers of puzzles, lovers of a challenge. Most of all, it is for those who think that the world of mathematics is orderly, logical, and intuitive-and are ready to learn otherwise! A pdf with errata is updated by the aut

  2. Estudo dos parâmetros Psicométricos do Teste Gestáltico Viso-Motor de Bender entre 2001 e 2011 = The Scientific Production About the Psychometric Parameters of Teste Gestáltico Viso-Motor of Bender between 2001 and 2011

    Directory of Open Access Journals (Sweden)

    Suehiro, Adriana Cristina Boulhoça

    2012-01-01

    Full Text Available Este estudo investigou a produção científica sobre o Teste Gestáltico Viso-Motor de Bender e, especialmente, sobre os seus parâmetros psicométricos entre 2001 e 2011. Dezessete relatos de pesquisa foram analisados com base na quantidade de artigos publicados por revista e por ano, distribuição da produção por origem, natureza da autoria, critérios de avaliação utilizados, método de análise e parâmetros psicométricos estudados. As produções se concentraram na revista Avaliação Psicológica e nos anos de 2006 e 2007. O sudeste foi a região que mais publicou nesse período e a autoria múltipla se fez presente em todos os relatos analisados. Os sistemas de avaliação mais utilizados foram o Bender-Sistema de Pontuação Gradual e o Koppitz. Verificou-se, ainda, que várias pesquisas focaram mais de um tipo de evidência de validade e precisão e que apenas um artigo se deteve apenas à precisão. O tipo de evidência mais frequente foram construto convergente-discriminante e precisão entre avaliadores

  3. Recognition of social identity in ants

    DEFF Research Database (Denmark)

    Bos, Nick; d'Ettorre, Patrizia

    2012-01-01

    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 o...... 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.......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...

  4. Ant Colony Optimization and Hypergraph Covering Problems

    CERN Document Server

    Pat, Ankit

    2011-01-01

    Ant Colony Optimization (ACO) is a very popular metaheuristic for solving computationally hard combinatorial optimization problems. Runtime analysis of ACO with respect to various pseudo-boolean functions and different graph based combinatorial optimization problems has been taken up in recent years. In this paper, we investigate the runtime behavior of an MMAS*(Max-Min Ant System) ACO algorithm on some well known hypergraph covering problems that are NP-Hard. In particular, we have addressed the Minimum Edge Cover problem, the Minimum Vertex Cover problem and the Maximum Weak- Independent Set problem. The influence of pheromone values and heuristic information on the running time is analysed. The results indicate that the heuristic information has greater impact towards improving the expected optimization time as compared to pheromone values. For certain instances of hypergraphs, we show that the MMAS* algorithm gives a constant order expected optimization time when the dominance of heuristic information is ...

  5. Optic disc detection using ant colony optimization

    Science.gov (United States)

    Dias, Marcy A.; Monteiro, Fernando C.

    2012-09-01

    The retinal fundus images are used in the treatment and diagnosis of several eye diseases, such as diabetic retinopathy and glaucoma. This paper proposes a new method to detect the optic disc (OD) automatically, due to the fact that the knowledge of the OD location is essential to the automatic analysis of retinal images. Ant Colony Optimization (ACO) is an optimization algorithm inspired by the foraging behaviour of some ant species that has been applied in image processing for edge detection. Recently, the ACO was used in fundus images to detect edges, and therefore, to segment the OD and other anatomical retinal structures. We present an algorithm for the detection of OD in the retina which takes advantage of the Gabor wavelet transform, entropy and ACO algorithm. Forty images of the retina from DRIVE database were used to evaluate the performance of our method.

  6. Comparative analysis of the macronutrient content of Central European ants (Formicidae): implications for ant-eating predators.

    Science.gov (United States)

    Pekár, S; Mayntz, D

    2014-03-01

    Prey nutrient quality determines predator performance. Polyphagous predators can address nutritional challenges by targeting prey with specific nutrient composition, but prey-specialised predators (e.g., ant-eaters), must obtain all nutrients from limited array of prey. Analysis of published data on prey specificity of European ant-eating spiders showed that some feed only on one ant genus, while others feed on several genera. Spiders feeding on several ant genera can possibly balance nutrient intake by selecting different ant prey. But monophagous species must extract all prey from a single prey species and can only vary nutrient intake by feeding on specific body parts. Most ant-eating spider species are catching Formica, Lasius and Messor ants, suggesting that these are most profitable ant species. We evaluated the nutritional content of a variety of 16 Central European ant species belonging to 11 genera and four subfamilies. We found that the nutritional composition, namely the amount of carbon, nitrogen and lipids, of European ants is heterogeneous. The largest variation in the amount of carbon and lipids was among ant subfamilies and species, while the largest variation in nitrogen was among ant genera. The largest amount of carbon and nitrogen was typical for Myrmicinae and the largest amount of lipids were typical for Formicinae. Within ants, the relative amounts of lipids were significantly higher in the gaster while the contents of carbon and nitrogen were highest in foreparts. Ant species did not cluster in the ordination space according to their taxonomic relationship or trophic strategy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. How load-carrying ants avoid falling over: mechanical stability during foraging in Atta vollenweideri grass-cutting ants.

    Directory of Open Access Journals (Sweden)

    Karin Moll

    Full Text Available BACKGROUND: Foraging workers of grass-cutting ants (Atta vollenweideri regularly carry grass fragments larger than their own body. Fragment length has been shown to influence the ants' running speed and thereby the colony's food intake rate. We investigated whether and how grass-cutting ants maintain stability when carrying fragments of two different lengths but identical mass. PRINCIPAL FINDINGS: Ants carried all fragments in an upright, backwards-tilted position, but held long fragments more vertically than short ones. All carrying ants used an alternating tripod gait, where mechanical stability was increased by overlapping stance phases of consecutive steps. The overlap was greatest for ants carrying long fragments, resulting in more legs contacting the ground simultaneously. For all ants, the projection of the total centre of mass (ant and fragment was often outside the supporting tripod, i.e. the three feet that would be in stance for a non-overlapping tripod gait. Stability was only achieved through additional legs in ground contact. Tripod stability (quantified as the minimum distance of the centre of mass to the edge of the supporting tripod was significantly smaller for ants with long fragments. Here, tripod stability was lowest at the beginning of each step, when the center of mass was near the posterior margin of the supporting tripod. By contrast, tripod stability was lowest at the end of each step for ants carrying short fragments. Consistently, ants with long fragments mainly fell backwards, whereas ants carrying short fragments mainly fell forwards or to the side. Assuming that transporting ants adjust neither the fragment angle nor the gait, they would be less stable and more likely to fall over. CONCLUSIONS: In grass-cutting ants, the need to maintain static stability when carrying long grass fragments has led to multiple kinematic adjustments at the expense of a reduced material transport rate.

  8. Polyethism in a colony of artificial ants

    CERN Document Server

    Marriott, Chris

    2011-01-01

    We explore self-organizing strategies for role assignment in a foraging task carried out by a colony of artificial agents. Our strategies are inspired by various mechanisms of division of labor (polyethism) observed in eusocial insects like ants, termites, or bees. Specifically we instantiate models of caste polyethism and age or temporal polyethism to evaluated the benefits to foraging in a dynamic environment. Our experiment is directly related to the exploration/exploitation trade of in machine learning.

  9. Ant colony optimization and constraint programming

    CERN Document Server

    Solnon, Christine

    2013-01-01

    Ant colony optimization is a metaheuristic which has been successfully applied to a wide range of combinatorial optimization problems. The author describes this metaheuristic and studies its efficiency for solving some hard combinatorial problems, with a specific focus on constraint programming. The text is organized into three parts. The first part introduces constraint programming, which provides high level features to declaratively model problems by means of constraints. It describes the main existing approaches for solving constraint satisfaction problems, including complete tree search

  10. Exploration versus exploitation in polydomous ant colonies.

    Science.gov (United States)

    Cook, Zoe; Franks, Daniel W; Robinson, Elva J H

    2013-04-21

    In socially foraging species resource information can be shared between individuals, increasing foraging success. In ant colonies, nestmate recruitment allows high exploitation rates at known resources however, to maximise foraging efficiency this must be balanced with searching for new resources. Many ant species form colonies inhabiting two or more spatially separated but socially connected nests: this type of organisation is known as polydomy. Polydomous colonies may benefit from increased foraging efficiency by carrying out dispersed-central place foraging. However, decentralisation of the colony may affect recruitment success by limiting interaction between ants based in separate nests. We use an agent-based model which compares the foraging success of monodomous and polydomous colonies in different food environments, incorporating recruitment through pheromone trails and group foraging. In contrast to previous results we show that polydomy is beneficial in some but not all cases. Polydomous colonies discover resources at a higher rate, making them more successful when food is highly dispersed, but their relative success can be lowered by limitations on recruitment success. Monodomous colonies can have higher foraging efficiency than polydomous colonies by exploiting food more rapidly. The results show the importance of interactions between recruitment strategy, colony size, and colony organisation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. El periodista, ante la espiral de silencio

    Directory of Open Access Journals (Sweden)

    Dr. Fermín Galindo Arranz

    1998-01-01

    Full Text Available La percepción de la profesión periodística y de su influencia cambia mucho a lo largo del tiempo, de las coyunturas históricas y de los diferentes países y sociedades en los que desempeñan su labor. En un contexto mundial, la gravedad de las situaciones de riesgo periodístico se encuadran en situaciones políticas, económicas o sociales también conflictivas; es entonces cuando se suele reproducir con facilidad en la opinión pública el fenómeno de la espiral del silencio, ante el que inevitablemente se sitúa el periodista. Por definición, el trabajo del periodista consiste en ser portavoz de las novedades que se producen, en dar informaciones y emitir opiniones en la esfera pública, se tiene que situar, por tanto, de forma individual y notoriamente pública ante los fenómenos de espiral de silencio que puedan producirse en la opinión pública. Antonio Tabucchi nos presenta en su novela "Sostiene Pereira" un ejemplo magnífico del dilema del periodista ante este tipo de situaciones.

  12. Indirect defense in a highly specific ant-plant mutualism.

    Science.gov (United States)

    Grangier, Julien; Dejean, Alain; Malé, Pierre-Jean G; Orivel, Jérôme

    2008-10-01

    Although associations between myrmecophytes and their plant ants are recognized as a particularly effective form of protective mutualism, their functioning remains incompletely understood. This field study examined the ant-plant Hirtella physophora and its obligate ant associate Allomerus decemarticulatus. We formulated two hypotheses on the highly specific nature of this association: (1) Ant presence should be correlated with a marked reduction in the amount of herbivory on the plant foliage; (2) ant activity should be consistent with the "optimal defense" theory predicting that the most vulnerable and valuable parts of the plant are the best defended. We validated the first hypothesis by demonstrating that for ant-excluded plants, expanding leaves, but also newly matured ones in the long term, suffered significantly more herbivore damage than ant-inhabited plants. We showed that A. decemarticulatus workers represent both constitutive and inducible defenses for their host, by patrolling its foliage and rapidly recruiting nestmates to foliar wounds. On examining how these activities change according to the leaves' developmental stage, we found that the number of patrolling ants dramatically decreased as the leaves matured, while leaf wounds induced ant recruitment regardless of the leaf's age. The resulting level of these indirect defenses was roughly proportional to leaf vulnerability and value during its development, thus validating our second hypothesis predicting optimal protection. This led us to discuss the factors influencing ant activity on the plant's surface. Our study emphasizes the importance of studying both the constitutive and inducible components of indirect defense when evaluating its efficacy and optimality.

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

    DEFF Research Database (Denmark)

    Offenberg, Hans Joachim

    2011-01-01

    Canopy dwelling weaver ants are widely distributed throughout the Old World Tropics where they build up high densities on their host trees. If managed properly the high number of ants will control a range of pest insects and benefit crop production. Simultaneously the ant larvae production, fuell...... be sustainable combined with their use in biocontrol, (ii) estimates of ant harvest yields from a mango plantation and (iii) how active feeding of ants may generate economic returns between 1.52 and 4.56 in a Thai market....... into a valuable and needed source of protein. Protein from conventional livestock production leave a high pressure on the environment as the food and farm area needed to produce each protein unit is high. For insect production these requirements are much lower and FAO has recently proposed research in insect...... 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...

  14. 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.

  15. Pommisatelliit Eesti kohal / Peep Pedmanson

    Index Scriptorium Estoniae

    Pedmanson, Peep, 1963-

    1997-01-01

    Discovery Channel Europe presenteeris Pirital toimunud telemessil videofilmi "Profid. Pommirühm" ("Professionals : Bomb Squad"), stsenarist, režissöör ja operaator Rein Kotov : Inglismaa - Eesti - Taani 1997

  16. Pommisatelliit Eesti kohal / Peep Pedmanson

    Index Scriptorium Estoniae

    Pedmanson, Peep, 1963-

    1997-01-01

    Discovery Channel Europe presenteeris Pirital toimunud telemessil videofilmi "Profid. Pommirühm" ("Professionals : Bomb Squad"), stsenarist, režissöör ja operaator Rein Kotov : Inglismaa - Eesti - Taani 1997

  17. Endel Aruja tagasivaates / Peep Pillak

    Index Scriptorium Estoniae

    Pillak, Peep, 1957-

    2012-01-01

    Endel Aruja pani aluse Torontos Tartu Intituudi raamatukogule. Aastakümneid osales ta juhtivalt pagulasorganisatsioonide tegevuses nii Suurbitannias kui ka Kanadas, samuti oli ta paljude erialaorganisatsioonide liige. 1986. aastal algatas Endel Aruja Eestisse raamatute saatmise aktsiooni Bookex. Rohkem kui kümme aastat kestnud aktsiooni käigus vahendas ta Eestisse ligikaudu 7500 kasti raamatuid

  18. Another peep behind the veil.

    Science.gov (United States)

    McKie, J; Kuhse, H; Richardson, J; Singer, P

    1996-08-01

    Harris argues that if QALYs are used only 50% of the population will be eligible for survival, whereas if random methods of allocation are used 100% will be eligible. We argue that this involves an equivocation in the use of "eligible", and provides no support for the random method. There is no advantage in having a 100% chance of being "eligible" for survival behind a veil of ignorance if you still only have a 50% chance of survival once the veil is lifted. A 100% chance of a 50% chance is still only a 50% chance. We also argue that Harris provides no plausible way of dealing with the criticism that his random method of allocation may result in the squandering of resources.

  19. Weimar, Euroopa kultuuripealinn / Peep Pillak

    Index Scriptorium Estoniae

    Pillak, Peep, 1957-

    1999-01-01

    1999. a. Euroopa kultuuripealinnast Weimarist. Linna minevikust, Weimaris elanud suurmehi, juubelitest, mida tähistatakse 1999. a. 1552. a. asus Weimarisse Lucas Cranach, isa alustatut jätkas Lucas Cranach noorem. 1919. a. alustas Walter Gropiuse juhtimisel Weimaris tegevust Bauhaus, kus aastatel 1922-1925 töötasid ka Wassily Kandinsky, Paul Klee

  20. Weimar, Euroopa kultuuripealinn / Peep Pillak

    Index Scriptorium Estoniae

    Pillak, Peep, 1957-

    1999-01-01

    1999. a. Euroopa kultuuripealinnast Weimarist. Linna minevikust, Weimaris elanud suurmehi, juubelitest, mida tähistatakse 1999. a. 1552. a. asus Weimarisse Lucas Cranach, isa alustatut jätkas Lucas Cranach noorem. 1919. a. alustas Walter Gropiuse juhtimisel Weimaris tegevust Bauhaus, kus aastatel 1922-1925 töötasid ka Wassily Kandinsky, Paul Klee

  1. Design of touch screen and irregular pipe saw pipe bender controlled by PLC%触摸屏与PLC控制的异型管锯管机的设计

    Institute of Scientific and Technical Information of China (English)

    蒋玲; 张超

    2012-01-01

    介绍了异型管锯管机的设计,通过异型管锯管机的结构与工作原理分析,设计了气动系统和以FX1N-40 MT为控制器、proface触摸屏为人机界面的PLC控制系统.该设备工作性能稳定、操作方便、经济适用,能够较好地完成异型管的切割.%This article describes the design process of the irregular pipe saw pipe bender. Through analysis of the irregular pipe saw pipe bender structure and working principle, pneumatic system and PLC control system with FX1N-40 MT for controller, proface touch screen for human-computer interface are designed, the equipment is stable performance, convenient operation, economy applicable, to better finish irregular pipe cutting.

  2. Ants at Plant Wounds: A Little-Known Trophic Interaction with Evolutionary Implications for Ant-Plant Interactions.

    Science.gov (United States)

    Staab, Michael; Fornoff, Felix; Klein, Alexandra-Maria; Blüthgen, Nico

    2017-09-01

    Extrafloral nectaries (EFNs) allow plants to engage in mutualisms with ants, preventing herbivory in exchange for food. EFNs occur scattered throughout the plant phylogeny and likely evolved independent from herbivore-created wounds subsequently visited by ants collecting leaked sap. Records of wound-feeding ants are, however, anecdotal. By surveying 38,000 trees from 40 species, we conducted the first quantitative ecological study of this overlooked behavior. Ant-wound interactions were widespread (0.5% of tree individuals) and occurred on 23 tree species. Interaction networks were opportunistic, closely resembling ant-EFN networks. Fagaceae, a family lacking EFNs, was strongly overrepresented. For Fagaceae, ant occurrence at wounds correlated with species-level leaf damage, potentially indicating that wounds may attract mutualistic ants, which supports the hypothesis of ant-tended wounds as precursors of ant-EFN mutualisms. Given that herbivore wounds are common, wound sap as a steadily available food source might further help to explain the overwhelming abundance of ants in (sub)tropical forest canopies.

  3. How Load-Carrying Ants Avoid Falling Over: Mechanical Stability during Foraging in Atta vollenweideri Grass-Cutting Ants

    Science.gov (United States)

    Moll, Karin; Roces, Flavio; Federle, Walter

    2013-01-01

    Background Foraging workers of grass-cutting ants (Atta vollenweideri) regularly carry grass fragments larger than their own body. Fragment length has been shown to influence the ants’ running speed and thereby the colony’s food intake rate. We investigated whether and how grass-cutting ants maintain stability when carrying fragments of two different lengths but identical mass. Principal Findings Ants carried all fragments in an upright, backwards-tilted position, but held long fragments more vertically than short ones. All carrying ants used an alternating tripod gait, where mechanical stability was increased by overlapping stance phases of consecutive steps. The overlap was greatest for ants carrying long fragments, resulting in more legs contacting the ground simultaneously. For all ants, the projection of the total centre of mass (ant and fragment) was often outside the supporting tripod, i.e. the three feet that would be in stance for a non-overlapping tripod gait. Stability was only achieved through additional legs in ground contact. Tripod stability (quantified as the minimum distance of the centre of mass to the edge of the supporting tripod) was significantly smaller for ants with long fragments. Here, tripod stability was lowest at the beginning of each step, when the center of mass was near the posterior margin of the supporting tripod. By contrast, tripod stability was lowest at the end of each step for ants carrying short fragments. Consistently, ants with long fragments mainly fell backwards, whereas ants carrying short fragments mainly fell forwards or to the side. Assuming that transporting ants adjust neither the fragment angle nor the gait, they would be less stable and more likely to fall over. Conclusions In grass-cutting ants, the need to maintain static stability when carrying long grass fragments has led to multiple kinematic adjustments at the expense of a reduced material transport rate. PMID:23300994

  4. Behavior of Ants Escaping from a Single-Exit Room

    Science.gov (United States)

    Wang, Shujie; Lv, Wei; Song, Weiguo

    2015-01-01

    To study the rules of ant behavior and group-formation phenomena, we examined the behaviors of Camponotus japonicus, a species of large ant, in a range of situations. For these experiments, ants were placed inside a rectangular chamber with a single exit that also contained a filter paper soaked in citronella oil, a powerful repellent. The ants formed several groups as they moved toward the exit to escape. We measured the time intervals between individual escapes in six versions of the experiment, each containing an exit of a different width, to quantify the movement of the groups. As the ants exited the chamber, the time intervals between individual escapes changed and the frequency distribution of the time intervals exhibited exponential decay. We also investigated the relationship between the number of ants in a group and the group flow rate. PMID:26125191

  5. Where and how Argentine ant (Linepithema humile) spreads in Corsica?

    Science.gov (United States)

    Blight, Olivier; Orgeas, Jérôme; Renucci, Marielle; Tirard, Alain; Provost, Erick

    2009-08-01

    The Argentine ant, Linepithema humile (Dolichoderinae), is one of the most widespread invasive ant species in the world. When established in optimal habitat, this species usually excludes most other local ants and can heavily impact other arthropods as well. Although Argentine ants have been present in southern Europe for more than 100 years, they were first noted in Corsica, a French Mediterranean island, in 1957 in only one urban station. In this study, we aimed to map precisely their geographical distribution in Corsica and to quantify their presence by using an infestation index. We recorded changes in the distribution of Argentine ants in Corsica over the past decade. Argentine ants appeared to be well established within their introduced range and spreading along the Corsican coasts principally through Human-mediated jump-dispersal but not homogenously.

  6. The use of computed tomography scans and the Bender Gestalt Test in the assessment of competency to stand trial and criminal responsibility in the field of mental health and law.

    Science.gov (United States)

    Mosotho, Nathaniel Lehlohonolo; Timile, Ino; Joubert, Gina

    computed tomography and the Bender Gestalt Test are some of the tests used routinely for the assessment of alleged offenders referred under Sections 77 and 78 of the Criminal Procedure Act 51 of 1977. An exploratory retrospective study was conducted at the Free State Psychiatric Complex. The aim of this study was to identify the extent to which the Bender Gestalt Test results and the computed tomography scans are associated with outcomes in the assessment of competency to stand trial and criminal responsibility in individuals referred to the Free State Psychiatric Complex (FSPC) observation unit. This was a cross-sectional study and the entire population of patients admitted in 2013 was included in the study. The clinical and demographic data were obtained from patient files. The majority of participants were black, males, single and unemployed. The most common diagnosis was schizophrenia. The current study showed no statistically significant association between the Bender Gestalt Test Hain's scores and the outcome of criminal responsibility and competency to stand trial. Similarly, the study also showed no statistically significant association between the presence of a brain lesion and the outcome of criminal responsibility and competency to stand trial. It was also concluded that as CT scans are expensive, patients should be referred for that service only when there is a clear clinical indication to do so. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Ant behaviour and seed morphology: a missing link of myrmecochory.

    Science.gov (United States)

    Gómez, Crisanto; Espadaler, Xavier; Bas, Josep M

    2005-12-01

    Seed dispersal by ants (myrmecochory) is mediated by the presence of a lipid-rich appendage (elaiosome) on the seed that induces a variety of ants to collect the diaspores. When seeds mature or fall onto the ground, these ant species transport them to their nest. After eating the elaiosome, the seed is discarded in nest galleries or outside, in the midden or farther away, where seeds can potentially germinate. The final location of seeds with their elaiosomes removed was evaluated to assess the importance of possible handles (structures that ants can grasp to carry) in transporting ants during re-dispersal experiments of seeds from nests of six species of ants. The results indicate that seeds remained within the nest because the ants were not able to transport them out of the nest. As a consequence of the elaiosome being removed, small ant species could not take Euphorbia characias seeds out of their nests. Only large ant species could remove E. characias seeds from their nests. Attaching an artificial handle to E. characias seeds allowed small ant species to redistribute the seeds from their nests. On the other hand, Rhamnus alaternus seeds that have a natural handle after the elaiosome removal were removed from the nests by both groups of ant species. If a seed has an element that acts as a handle, it will eventually get taken out of the nest. The ants' size and their mandible gap can determine the outcome of the interaction (i.e. the pattern of the final seed shadow) and as a consequence, could influence the events that take place after the dispersal process.

  12. Parallelizing Ant Colony Optimization via Area of Expertise Learning

    Science.gov (United States)

    2007-09-13

    lutions for all but the most trivial instances. Ant colony optimization (ACO) is a simple metaheuristic that can effectively solve problems in these...expertise” technique is applied to two problem domains: gridworld and the traveling salesman problem. 1.1 Motivation ACO is a metaheuristic that generates...independent ant agents, an obvious extension of the ant colony framework is to implement the algorithm in a parallel environment. One of the main

  13. Evolutionarily advanced ant farmers rear polyploid fungal crops

    OpenAIRE

    Pepijn W Kooij; Aanen, D. K.; Schiøtt, M.; Boomsma, Jacobus J.

    2015-01-01

    Abstract Innovative evolutionary developments are often related to gene or genome duplications. The crop fungi of attine fungus‐growing ants are suspected to have enhanced genetic variation reminiscent of polyploidy, but this has never been quantified with cytological data and genetic markers. We estimated the number of nuclei per fungal cell for 42 symbionts reared by 14 species of Panamanian fungus‐growing ants. This showed that domesticated symbionts of higher attine ants are polykaryotic ...

  14. Does Trichomes on the Plant Epidermic Surface Disturb Ants Locomotion?

    OpenAIRE

    Danon C. Cardoso; Maykon P Cristiano; Lenise C. M. Vilela; Tiago D. A. Martins

    2009-01-01

    Problem Statement: Many morphological characteristics, both physical and chemical, are used in the defense against herbivores on plants. Trichomes are structures used by plants as physics defense and when associated with glands combine physics and chemistry defense. Many species of ants are herbivores and use leaves and seeds, others ants use Extra Floral Nectars as a food resource, and the majority of the species are predators of other ants and other insects, &#...

  15. Rhabdomyolysis and Acute Renal Failure After Fire Ant Bites

    OpenAIRE

    Koya, Supriya; Crenshaw, Daryl; Agarwal, Anupam

    2007-01-01

    We describe a 59-year-old patient who developed acute renal failure because of rhabdomyolysis after extensive red fire ant bites. This case illustrates a serious systemic reaction that may occur from fire ant bites. Consistent with the clinical presentation in rhabdomyolysis associated with non-traumatic causes, hyperkalemia, hypophosphatemia, hypocalcemia, and high anion gap acidosis were not observed in this patient. While local allergic reactions to fire ant bites are described in the lite...

  16. [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.

  17. Laboratory host specificicty testing of the fire ant microsporidian pathogen Vairimorpha invictae (Microsporidia: Burenellidae)

    Science.gov (United States)

    The host specificity of Vairimorpha invictae, a microsporidian pathogen of fire ants in South America, was assessed in the laboratory with the tropical fire ant, Solenopsis geminata, the southern fire ant, Solenopsis xyloni, and the Argentine ant, Linepithema humile. The two fire ant species are fo...

  18. Long-term persistence of a neotropical ant-plant population in the absence of obligate plant-ants.

    Science.gov (United States)

    Moraes, Sinara C; Vasconcelos, Heraldo L

    2009-09-01

    Interactions between ants and ant-plants are considered classic examples of obligate mutualisms. Previous studies have indicated that for many ant-plants the loss of ant colonies results in severe defoliation or mortality. Although individual plants can persist for some period of time without their mutualistic partners, to date populations of ant-free plants have only been recorded at high altitudes or on remote islands where herbivores are also scarce. We studied the interaction between ants, herbivores, and the ant-plant Tococa guianensis in the Cerrado region of central Brazil. Using a survey conducted across a large geographic region, we show that there is interpopulation variation in ant occupancy across sites and habitats. At most sites surveyed, plants were inhabited by Allomerus octoarticulatus, an obligate plant-ant. Plants with obligate ants had significantly lower standing levels of herbivore damage than plants with opportunistic ants and plants with no ant occupants. Furthermore, experimental removal of A. octoarticulatus resulted in increased levels of damage in both young and mature leaves. Despite the protection provided by obligate ants, populations of T. guianensis were found to persist without these ants in some areas. Plants without A. octoarticulatus had significantly greater leaf toughness and trichome density than those with A. octoarticulatus. Furthermore, trichome density in plants with A. octoarticulatus increased after ants were removed, probably as a response induced by increased levels of herbivore damage. To our knowledge, this is the first record of the occurrence of native myrmecophyte populations without their mutualistic ants in mainland low-elevation sites. Several factors may help to explain the long-term persistence of T. guianensis populations without plant-ants in some areas of the Brazilian Cerrado, including its potential for induced morphological defenses against insect herbivores and selection for increased levels of

  19. Ant-Crypto, a Cryptographer for Data Encryption Standard

    Directory of Open Access Journals (Sweden)

    Salabat Khan

    2013-01-01

    Full Text Available Swarm Intelligence and Evolutionary Techniques are attracting the cryptanalysts in the field of cryptography. This paper presents a novel swarm based attack called Ant-Crypto (Ant-Cryptographer for the cryptanalysis of Data Encryption Standard (DES. Ant-Crypto is based on Binary Ant Colony Optimization (BACO i.e. a binary search space based directed graph is modeled for efficiently searching the optimum result (an original encryption key, in our case. The reason that why evolutionary techniques are becoming attractive is because of the inapplicability of traditional techniques and brute force attacks against feistel ciphers due to their inherent structure based on high nonlinearity and low autocorrelation. Ant-Crypto uses a known-plaintext attack to recover the secret key of DES which is required to break/ decipher the secret messages. Ant-Crypto iteratively searches for the secret key while generating several candidate optimum keys that are guessed across different runs on the basis of routes completed by ants. These optimum keys are then used to find each individual bit of the 56 bit secret key used during encryption by DES. Ant-Crypto is compared with some other state of the art evolutionary based attacks i.e. Genetic Algorithm and Comprehensive Binary Particle Swarm Optimization. The experimental results show that Ant-Crypto is an effective evolutionary attack against DES and can deduce large number of valuable bits as compared to other evolutionary algorithms; both in terms of time and space complexity.

  20. 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...