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Sample records for vitripennis walker hymenoptera

  1. Desempenho reprodutivo de Nasonia vitripennis Walker (Hymenoptera: Pteromalidae em pupas crioconservadas de Chrysomya megacephala Fabricius (Diptera: Calliphoridae: avaliação preliminar Reproductive performance of Nasonia vitripennis Walker (Hymenoptera: Pteromalidae on Chrysomya megacephala Fabricius (Diptera: Calliphoridae cryopreserved pupae: preliminary evaluation

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    Eliane Maria Vieira Milward-de-Azevedo

    2004-02-01

    Full Text Available Avaliou-se o desempenho reprodutivo de Nasonia vitripennis Walker (Hymenoptera: Pteromalidae em pupas de Chrysomya megacephala Fabricius (Diptera: Calliphoridae previamente armazenadas a - 20ºC de temperatura, durante 77 dias, com e sem passagem prévia em nitrogênio líquido (NL por um, três e 15 minutos. O grupo controle foi caracterizado por pupas hospedeiras frescas. Os muscóides foram expostos aos parasitóides durante 72 horas. Utilizou-se a relação de uma pupa muscóide por fêmea parasitóide. A amostra de pupas frescas permitiu a emergência de 15 parasitóides/ pupa, em média, enquanto 10 parasitóides / pupa emergiram dos espécimens prévia e diretamente armazenados em freezer (-20ºC. Observou-se um acentuado decréscimo do desempenho reprodutivo dos microhimenópteros que exploraram os substratos previamente submetidos ao NL durante um, três e 15 minutos (: 6,1; 5,5 e 5,7, respectivamente. A dissecação das pupas hospedeiras revelou um expressivo número de pteromalídeos imaturos, nas amostras que foram expostas ao NL, e de adultos faratos, em todos os tratamentosThe reproductive performance of Nasonia vitripennis Walker (Hymenoptera: Pteromalidae was evaluated on pupae of Chrysomya megacephala Fabricius (Diptera: Calliphoridae kept at -20ºC, during 77 days, with and no previous passage for liquid nitrogen (NL by one, three and 15 minutes. Control groups were characterized for fresh pupae hosts. There was one pupa for each parasitoid. The sample of fresh pupae exhibited average of 15 emergent parasitoids / pupa while pupae stored directly at freezer (-20ºC presented an average of 10 emergent parasitoids / pupa. In the samples exposed at one, three and 15 minutes in NL, accentuated decrease was observed on emergent hymenopterans reproductive performance (: 6.1; 5.5 and 5.7 respectively. The dissection of pupae revealed a large number of immature pteromalid in the groups with liquid nitrogen passage and farate adults in

  2. Durations of immature stage development period of Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae) under laboratory conditions: implications for forensic entomology.

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    Mello, Renata da Silva; Aguiar-Coelho, Valéria M

    2009-01-01

    Some microhymenopterans are parasitoids of flies of forensic importance. Their parasitic habit can alter the duration of post-embryonic development of these flies, altering the postmortem interval. In order to analyze possible alterations occurring during the immature development period of Nasonia vitripennis, this study tested different quantitative associations between female parasitoids and pupae of Chrysomya megacephala, which were defined by: (a) one pupa was exposed to different numbers of female parasitoids (1:1, 1:3, 1:5, 1:7, 1:9, 1:11) and (b) different numbers of pupae were exposed to one female parasitoid (1:1, 2:1, 3:1, 4:1, 5:1). Analysis of variance (5% significance level) and Tukey's honestly significant difference tests were used for statistical analysis. There was a tendency of prolongation of the duration of parasitoid development, both by increasing the number of female parasitoids and by increasing the number of hosts in the associations. By increasing the number of female parasitoids per host, there is a possibility of increasing the occurrence of superparasitism, leading to competition for food source, then prolonging the duration of the immature development period. Increasing the number of hosts in the associations, females may distribute their postures among the available pupae and can cause reduction of the number of eggs per host. Since these insects are gregarious, the reduction of the number of eggs may delay the offspring development.

  3. Morphology and Ultrastructure of Brain Tissue and Fat Body from the Flesh Fly, Sarcophaga bullata Parker (Diptera: Sarcophagidae, Envenomated by the Ectoparasitic Wasp Nasonia vitripennis (Walker (Hymenoptera: Pteromalidae

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    David B. Rivers

    2011-01-01

    Full Text Available This study tested the hypothesis that venom from the ectoparasitic wasp Nasonia vitripennis targets brain tissue and fat body from its flesh fly host, Sarcophaga bullata. By 1 h postenvenomation, some brain neurons began to show irregularities in nuclear shape, and though they were predominately euchromatic, there was evidence of heterochromatin formation. Irregularity in the nuclear envelope became more prominent by 3 h after envenomation, as did the condensation of heterochromatin. The severity of ultrastructural changes continued to increase until at least 24 h after parasitoid attack. At this point, cellular swelling and extensive heterochromatic inclusions were evident, multivesicular bodies occurred in the cytoplasm of some cells, and the rough endoplasmic reticulum was dilated in many of the cells. Immunohistochemical staining revealed significant apoptosis in neurons located in brain tissues. By contrast, there was no evidence of any morphological or ultrastructural disturbances in fat body tissues up to 24 h after envenomation, nor did any of the cells display signs of cell death.

  4. Sex determination in the haplodiploid wasp Nasonia vitripennis (Hymenoptera Chalcidoidea) : A critical consideration of models and evidence

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    Beukeboom, Leo W.; Kamping, Albert; van de Zande, Louis

    Sex determining mechanisms are highly diverse. Like all Hymenoptera, the parasitic wasp Nasonia vitripennis reproduces by haplodiploidy: males are haploid and females are diploid. Sex in Nasonia is not determined by complementary alleles at sex loci. Evidence for several alternative models is

  5. Phylogeography of Nasonia vitripennis (Hymenoptera) indicates a mitochondrial-Wolbachia sweep in North America

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    Raychoudhury, R.; Grillenberger, B. K.; Gadau, J.; Bijlsma, R.; van de Zande, L.; Werren, J. H.; Beukeboom, L. W.

    Here we report evidence of a mitochondrial-Wolbachia sweep in North American populations of the parasitoid wasp Nasonia vitripennis, a cosmopolitan species and emerging model organism for evolutionary and genetic studies. Analysis of the genetic variation of 89 N. vitripennis specimens from Europe

  6. Comparative venom toxicity between Pteromalus puparum and Nasonia vitripennis (Hymenoptera: Pteromalidae) toward the hemocytes of their natural hosts, non-target insects and cultured insect cells.

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    Zhang, Zhong; Ye, Gong-Yin; Cai, Jun; Hu, Cui

    2005-09-01

    Crude venoms from two parasitoid species, Pteromalus puparum and Nasonia vitripennis (Hymenoptera: Pteromalidae) were assayed for biological activities toward hemocytes from two species of their natural hosts and eight species of their non-natural hosts as well as two lines of cultured Lepidoptera cells, respectively. By inhibiting the spreading and viability of insect hemocytes, the venom from P. puparum displayed significantly higher activities toward plasmatocytes and granular cells from both larvae and pupae of two natural hosts, Pieris rapae and Papilio xuthus, and lower activity toward those from Spodoptera litura, Musca domestica and Sarcophaga peregrina. However, no effect was found towards any type of hemocytes from other five insects tested, namely, Ectropis oblique, Galleria mellonella, Sesamia inferens, Bombyx mori and Parnara guttata. In contrast, the venom from N. vitripennis showed a narrower range of targeted insects. It appeared to have highly adverse effects on the spreading and viability of plasmatocytes and granular cells only from the natural hosts, M. domestica and S. peregrina, little toxicity to cells from P. rapae and P. xuthus, and no effect on any of the other insects tested. Pteromalus puparum venom also apparently presented a high ability to block the spreading of Tn-5B1-4 cells derived from Trichoplusia ni, and high cytotoxicity to the cells and Ha cells derived from Helicoverpa armigera. Nasonia vitripennis venom, however, only had a marked lethal effect to Ha cells. In addition, the possibility that the host range of a defined parasitoid could be assessed using our method of treating hemocytes from candidate insects with venom in vitro, and the potential of our venoms tested in the development of bio-insecticides, insect-resistant transgenic plants, are discussed.

  7. Side Effects of IGR Cyromazine on Nasonia vitripennis (Hymenoptera: Pteromalidae, a Parasitic Wasp of House Fly Pupae

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    B Vazirianzadeh

    2008-12-01

    Full Text Available "nBackground: Combination of cyromazine as an Insect Growth Regulator (IGR and Nasonia vitripennis (Hymenop¬tera: Pteromalidae a parasitic wasp may be an effective tool for reducing the house-fly populations in poultry houses and livestock farms. This study was conducted to assess the side effects of the IGR cyromazine on the level of parasit¬ism and numbers and the longevity of emerged N. vitripennis parasitoids from house fly pupae."nMethods: Cyromazine treated cloth target was used as the contaminating method of the parasitoids which was ap¬plied in this research study. "nResults: The Weibull distribution showed that there was no significant difference among controls and cyromazine treated targets for longevity data. There was no significant effect of cyromazine on the level of parasitism of N. vitripennis using 2 test. One-way ANOVA showed that the actual numbers emerging were significantly higher in the control than in two cyromazine treatments; however, it is a useful phenomenon because of reducing the hyperparasitism."nConclusion: There is a good consistency between using N. vitripennis and 1.1% or 0.9% cyromazine treated targets. There¬fore cyromazine treated targets can be applied as a safe delivery vehicle for applying the cyromazine IGR in the poultry houses and livestock farms in an Integrated Pest Management (IPM program.

  8. Side Effects of IGR Cyromazine on Nasonia vitripennis (Hymenoptera: Pteromalidae, a Parasitic Wasp of House Fly Pupae

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    B Vazirianzadeh

    2008-12-01

    Full Text Available Background: Combination of cyromazine as an Insect Growth Regulator (IGR and Nasonia vitripennis (Hymenop¬tera: Pteromalidae a parasitic wasp may be an effective tool for reducing the house-fly populations in poultry houses and livestock farms. This study was conducted to assess the side effects of the IGR cyromazine on the level of parasit¬ism and numbers and the longevity of emerged N. vitripennis parasitoids from house fly pupae.Methods: Cyromazine treated cloth target was used as the contaminating method of the parasitoids which was ap¬plied in this research study. Results: The Weibull distribution showed that there was no significant difference among controls and cyromazine treated targets for longevity data. There was no significant effect of cyromazine on the level of parasitism of N. vitripennis using 2 test. One-way ANOVA showed that the actual numbers emerging were significantly higher in the control than in two cyromazine treatments; however, it is a useful phenomenon because of reducing the hyperparasitism.Conclusion: There is a good consistency between using N. vitripennis and 1.1% or 0.9% cyromazine treated targets. There¬fore cyromazine treated targets can be applied as a safe delivery vehicle for applying the cyromazine IGR in the poultry houses and livestock farms in an Integrated Pest Management (IPM program.

  9. Effects on microhymenopteran progeny of different host exposure periods (Chrysomya megacephala, Calliphoridae to the parasitoid wasp Nasonia vitripennis (Hymenoptera: Pteromalidae

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    Renata da Silva Mello

    2010-02-01

    Full Text Available To test the assumption that exposure of the host to parasitoid for long periods could provoke superparasitism, the aim of this work was to test the consequences on the immature development time, productivity of parasitoids per pupa, sex ratio and rate of parasitism of Nasonia vitripennis bred in Chrysomya megacephala pupae. Each individual pupa was placed in a glass tube with one parasitoid female for 24, 48, 72 and 96 h period of exposure, under controlled laboratory conditions. Twenty replicates of each period were performed. ANOVA with a 5% significance level was applied. The 72 h exposure caused the immature development time to increase. The mean parasitoids emergence per pupa did not vary significantly with the time of exposure. There were a significantly higher number of females than males and a trend in sex ratio deviation towards the females in all of the treatments. An increase in the number of unviable pupae rates were observed with increased exposure time.Para testar a hipótese que longos períodos de exposição do hospedeiro ao parasitóide podem ocasionar o superparasitismo, o presente estudo teve como objetivo testar as conseqüências sobre o tempo de desenvolvimento do imaturo, a produtividade de parasitóides, razão sexual e taxa de parasitismo de Nasonia vitripennis criadas em pupas de Chrysomya megacephala. Cada pupa foi individualizada e alocada em um tudo de ensaio com uma fêmea de N. vitripennis por 24, 48, 72 ou 96 h, sob condições laboratoriais controladas. Foram realizadas 20 réplicas para cada período de exposição. ANOVA com significância de 5 % foi aplicada. A exposição de 72 h causou um aumento no tempo desenvolvimento. A média de emergência de parasitóides não variou significativamente entre os tempos de exposição. Houve um número significativamente maior de fêmeas e uma tendência ao desvio da razão sexual para fêmeas em todos os tratamentos. Foi verificado um aumento no número de pupas invi

  10. A new species of Ormocerus Walker (Hymenoptera: Pteromalidae) from North America and a range expansion for Ormocerus latus Walker

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    Ormocerus dirigoius, n. sp. is described and compared to the North American O. americanus Dzhanokmen and Grissell and European species O. latus Walker and O. vernalis Walker. A range expansion into the Nearctic is reported for O. latus, previously only known from the Palearctic. Specimens were colle...

  11. The Community of Hymenoptera Parasitizing Necrophagous Diptera in an Urban Biotope

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    Frederickx, Christine; Dekeirsschieter, Jessica; Verheggen, François J.; Haubruge, Eric

    2013-01-01

    Most reports published in the field of forensic entomology are focused on Diptera and neglect the Hymenoptera community. However, Hymenoptera are part of the entomofaunal colonization of a dead body. The use of Hymenoptera parasitoids in forensic entomology can be relevant to evaluate the time of death. Hymenoptera parasitoids of the larvae and pupae of flies may play an important role in the estimation of the post-mortem period because their time of attack is often restricted to a small, well-defined window of time in the development of the host insect. However, these parasitoids can interfere with the developmental times of colonizing Diptera, and therefore a better understanding of their ecology is needed. The work reported here monitored the presence of adult Hymenoptera parasitoids on decaying pig carcasses in an urban biotope during the summer season (from May to September). Six families and six species of parasitoids were recorded in the field: Aspilota fuscicornis Haliday (Braconidae), Alysia manducator Panzer, Nasonia vitripennis Walker (Pteromalidae), Tachinaephagus zealandicus Ashmead (Encyrtidae), Trichopria sp. (Diapriidae), and Figites sp. (Figitidae). In the laboratory, five species emerged from pupae collected in the field: Trichopria sp., Figites sp., A. manducator, N. vitripennis, and T. zealandicus. These five species colonize a broad spectrum of Diptera hosts, including those species associated with decomposing carcasses, namely those from the families Calliphoridae, Muscidae, Fanniidae, and Sarcophagidae. PMID:23895458

  12. Review of the East Palaearctic and North Oriental Psyttalia Walker, with the description of three new species (Hymenoptera, Braconidae, Opiinae).

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    Wu, Qiong; van Achterberg, Cornelis; Tan, Jiang-Li; Chen, Xue-Xin

    2016-01-01

    The East Palaearctic and North Oriental species of the genus Psyttalia Walker (Hymenoptera, Braconidae, Opiinae) are reviewed. Three new species are described and illustrated: Psyttalia latinervis Wu & van Achterberg, sp. n . and Psyttalia majocellata Wu & van Achterberg, sp. n . from China, and Psyttalia spectabilis van Achterberg, sp. n. from Japan. Coeloreuteus formosanus Watanabe, 1934, Opius (Lissosema) proclivis Papp, 1981, Opius (Psyttalia) subcyclogaster Tobias, 1998, Opius (Psyttalia) darasunicus Tobias, 1998, Opius (Psyttalia) cyclogastroides Tobias, 1998, Psyttalia extensa Weng & Chen, 2001, and Rhogadopsis longicaudifera Li & van Achterberg, 2013, are new synonyms of Psyttalia cyclogaster (Thomson, 1895); Opius (Psyttalia) ophthalmicus Tobias, 1977, and Opius (Psyttalia) brevitemporalis Tobias, 1998, of Psyttalia carinata (Thomson, 1895) and both Opius (Psyttalia) vacuus Tobias, 1998, and Opius (Lissosema) longurius Chen & Weng, 1995, of Rhogadopsis mediocarinata (Fischer, 1963). Phaedrotoma daghestanicum (Telenga, 1950), Rhogadopsis mediocarinata (Fischer, 1963) and Rhogadopsis mystica (Fischer, 1963) are new combinations. New records are Psyttalia carinata (Thomson, 1895) from The Netherlands and Norway, and Psyttalia cyclogaster (Thomson, 1895) from Japan. A lectotype is designated for Psyttalia carinata (Thomson, 1895) and Psyttalia cyclogaster (Thomson, 1895). A key to the East Palaearctic and North Oriental species of the genus Psyttalia Walker is included.

  13. Review of the East Palaearctic and North Oriental Psyttalia Walker, with the description of three new species (Hymenoptera, Braconidae, Opiinae

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    Qiong Wu

    2016-11-01

    Full Text Available The East Palaearctic and North Oriental species of the genus Psyttalia Walker (Hymenoptera, Braconidae, Opiinae are reviewed. Three new species are described and illustrated: P. latinervis Wu & van Achterberg, sp. n. and P. majocellata Wu & van Achterberg, sp. n. from China, and P. spectabilis van Achterberg, sp. n. from Japan. Coeloreuteus formosanus Watanabe, 1934, Opius (Lissosema proclivis Papp, 1981, O. (Psyttalia subcyclogaster Tobias, 1998, O. (P. darasunicus Tobias, 1998, O. (P. cyclogastroides Tobias, 1998, Psyttalia extensa Weng & Chen, 2001, and Rhogadopsis longicaudifera Li & van Achterberg, 2013, are new synonyms of Psyttalia cyclogaster (Thomson, 1895; Opius (Psyttalia ophthalmicus Tobias, 1977, and O. (P. brevitemporalis Tobias, 1998, of Psyttalia carinata (Thomson, 1895 and both O. (P. vacuus Tobias, 1998, and O. (Lissosema longurius Chen & Weng, 1995, of Rhogadopsis mediocarinata (Fischer, 1963. Phaedrotoma daghestanicum (Telenga, 1950, Rhogadopsis mediocarinata (Fischer, 1963 and R. mystica (Fischer, 1963 are new combinations. New records are Psyttalia carinata (Thomson, 1895 from The Netherlands and Norway, and P. cyclogaster (Thomson, 1895 from Japan. A lectotype is designated for Psyttalia carinata (Thomson, 1895 and P. cyclogaster (Thomson, 1895. A key to the East Palaearctic and North Oriental species of the genus Psyttalia Walker is included.

  14. A survey for potential biological control agents of Pereskia aculeata Miller (Cactaceae) in Brazil reveals two new species of Horismenus Walker (Hymenoptera: Eulophidae).

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    Pikart, Tiago G; Costa, Valmir A; Hansson, Christer; Cristo, Sandra C DE; Vitorino, Marcelo D

    2017-05-30

    This paper deals with the description of two new species of Horismenus Walker (Hymenoptera: Eulophidae) from Brazil, parasitoids of larvae of Adetus analis (Haldeman) (Coleoptera: Cerambycidae). Both species are similar to Horismenus steirastomae (Girault), a species that also parasitizes cerambycids. Adetus analis is a pest of Sechium edule (Jacq.) Swartz (Cucurbitaceae), a minor crop in Brazil, Argentina and U.S.A., but also feeds in stems of Pereskia aculeata Miller (Cactaceae), an ornamental plant that has become a problematic weed species in Africa, where it was introduced. The two new Horismenus species are described, diagnosed, and compared to H. steirastomae.

  15. Disruption of pupariation and eclosion behavior in the flesh fly, Sarcophaga bullata Parker (Diptera: Sarcophagidae), by venom form the ectoparasitic wasp Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae)

    Czech Academy of Sciences Publication Activity Database

    Rivers, D. B.; Žďárek, Jan; Denlinger, D. L.

    2004-01-01

    Roč. 57, - (2004), s. 78-91 ISSN 0739-4462 R&D Projects: GA ČR GA522/01/0501 Grant - others:USDA-NRI(US) 98-35302-6659; USDA-NRICGP(US) 2001-1005 Institutional research plan: CEZ:AV0Z4055905 Keywords : ectoparasitoid * ecdysone * fly development Subject RIV: CC - Organic Chemistry Impact factor: 1.173, year: 2004

  16. Plant water stress effects on the net dispersal rate of the insect vector Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae) and movement of its egg parasitoid, Gonatocerus ashmeadi Girault (Hymenoptera: Mymaridae)

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    Homalodisca vitripennis, one of the main vectors of Xylella fastidiosa, is associated with citrus plantings in California, USA. Infested citrus orchards act as a source of vectors to adjacent vineyards where X. fastidiosa causes Pierce’s disease (PD). An analysis of the pattern and rate of movement ...

  17. Three new species of Horismenus Walker (Hymenoptera: Eulophidae) associated with seed pods of Pithecellobium dulce (Fabaceae).

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    Pikart, Tiago G; Costa, Valmir A; Hansson, Christer; Zanuncio, José C; Serrão, José E

    2015-08-04

    Horismenus abnormicaulis sp. nov., H. patensis sp. nov. and H. zuleidae sp. nov. (Hymenoptera: Eulophidae), all authored by Pikart, Costa & Hansson, are described from material obtained from seed pods of Pithecellobium dulce (Roxb.) Benth. (Fabaceae) collected in Northeastern Brazil. The seed pods were infested with larvae of Coleoptera (Chrysomelidae (Bruchinae) and Curculionidae). The associations of the Horismenus species and the beetle larvae have not been established. Morphological similarities between these new species and previously described species with host known suggest that H. patensis and H. zuleidae are primary parasitoids of Bruchinae, whereas H. abnormicaulis may act as a hyperparasitoid on other Horismenus species. The three species are compared with similar species of Horismenus.

  18. Progeny of Spalangia endius Walker, 1839 (Hymenoptera: Pteromalidae) in Musca domestica L., 1758 (Diptera: Muscidae) non-viable pupae irradiated by gamma Cobalt-60 and cold stored

    International Nuclear Information System (INIS)

    Itepan, Sara Eloiza Zen.

    1992-06-01

    This study was designed to test acceptability of cold stored irradiated and non-irradiated pupae of Musca domestica L., 1758 (Diptera: Muscidae) by the parasitoid Spalangia endius Walker, 1839 (Hymenoptera: Pteromalidae). The work was carried out in the laboratory of the Entomology Section of the Center of Nuclear Energy in Agriculture (CENA/USP) and in the laboratory of Biological Control of House Flies Eduardo Hiroshi Mizumoto of Entomology Department of the College of Agriculture Luiz de Queiroz (ESALQ/USP), Piracicaba, Sao Paulo, Brazil. The gamma radiation source used was a Cobalt-60 irradiator, Gamma bean-650, with an initial activity of 1,6265 x 10 4 Bq (6,746 Ci). The radiation LD 50 e LD 100 , using a dose ratio of 1457 Gy/h, for 12, 24, 36, 48, 60 and 72 hours old pupae and resulted in 15.35; 15.69; 11.30; 49.4; 142.78 and 175 Gy for LD 50 and 20, 22.5; 32.5; 175; 225 and 300 Gy for LD'1 00 respectively. Following exposure, the pupae were kept in climate chamber at 27 ± 3 0 C and 75 ± % of relative humidity, until all adults had emerged. In succession, 24, 48 and 72 hour-old pupae were exposed to gamma irradiation with a dose of 1440 Gy/hour, in their respective lethal doses. Following the exposure the pupae were stored at cool temperature (10 ± 2 0 C) for different periods of time (5, 15, 20 and 30 days). The same treatment was given for non-irradiated pupae. After the storage period the pupae were expose for 24 h to S. endius in a ratio of 1:10 parasitoid-host. It was not observed any statistical difference (Turkey 5%) in progeny of males and females emerged from irradiated and non-irradiated pupae. There was a preference of the parasitoid to pupae of 48 hours old followed by 24 and 72 hours old for storage period more than 5 days and shorter than 20 days. (author). 50 refs., 6 figs., 17 tabs

  19. Agile Walker.

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    Katz, Reuven

    2015-01-01

    The goal of the Agile Walker is to improve the outdoor mobility of healthy elderly people with some mobility limitations. It is a newly developed, all-terrain walker, equipped with an electric drive system and speed control that can assists elderly people to walk outdoors or to hike. The walker has a unique product design with an attractive look that will appeal to "active-agers" population. This paper describes product design requirements and the development process of the Agile Walker, its features and some preliminary testing results.

  20. Increase of acceptability period of Musca domestic l., 1758 (diptera: muscidae) pupae, irradiated by gamma radiation as host of the pupal parasitoid Spalangia endius, Walker, 1839 (hymenoptera: pteromalidae)

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    Itepan, Natanael M., E-mail: nmitepan@ifsp.edu.br [Instituto Federal de Sao Paulo (IFSP), Piracicaba, SP (Brazil); Itepan, Sara E.D.Z., E-mail: sarazenitepan@ig.com.br [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia Ciencias e Letras; Arthur, Valter, E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

    2013-07-01

    This experiment was carried out in Biological Control of Domestic Fly 'Eduardo Hiroshi Mizumoto' Laboratory at Entomology and Acarology Department (LEA/ESALQ/USP) and in Food Irradiation and Radioentomology Laboratory (LIARE/CENA/USP). The gamma radiation source used was a Co-60 irradiator model Gammabeam-650 of the Atomic Energy of Canada Ltd. whose activity in the beginning of the experiments was 9.8x10{sup 13} Bq. (2,644 Ci). The lots of pupae of Musca domestic L., 1758 and the parasitoid Spalangia endius Walker, 1839 had been kept in acclimatized room with 25 ± 2 deg C of temperature and 70 ± 5% of relative humidity. This experiment was designed to investigate if the non-viabilization M. domestic pupae, using gamma radiation, could build up the acceptability period as host of the pupal parasitoid S. endius. At these age intervals, the dose to prevent adult emergence was 25, 220, 360 and 520 Gy respectively. The 1, 2, 3 and 4 days old pupae were irradiated (dose rate: 1,510 Gy/hr) and exposed to the parasitoid S. endius at a proportion of one female parasitoid to five housefly pupae, during different periods after the irradiation. The results allow us to conclude that irradiation increase the acceptability period of the housefly pupae by the parasitoid. The best age to irradiate the housefly pupae was one day. (author)

  1. Increase of acceptability period of Musca domestic l., 1758 (diptera: muscidae) pupae, irradiated by gamma radiation as host of the pupal parasitoid Spalangia endius, Walker, 1839 (hymenoptera: pteromalidae)

    International Nuclear Information System (INIS)

    Itepan, Natanael M.; Itepan, Sara E.D.Z.

    2013-01-01

    This experiment was carried out in Biological Control of Domestic Fly 'Eduardo Hiroshi Mizumoto' Laboratory at Entomology and Acarology Department (LEA/ESALQ/USP) and in Food Irradiation and Radioentomology Laboratory (LIARE/CENA/USP). The gamma radiation source used was a Co-60 irradiator model Gammabeam-650 of the Atomic Energy of Canada Ltd. whose activity in the beginning of the experiments was 9.8x10 13 Bq. (2,644 Ci). The lots of pupae of Musca domestic L., 1758 and the parasitoid Spalangia endius Walker, 1839 had been kept in acclimatized room with 25 ± 2 deg C of temperature and 70 ± 5% of relative humidity. This experiment was designed to investigate if the non-viabilization M. domestic pupae, using gamma radiation, could build up the acceptability period as host of the pupal parasitoid S. endius. At these age intervals, the dose to prevent adult emergence was 25, 220, 360 and 520 Gy respectively. The 1, 2, 3 and 4 days old pupae were irradiated (dose rate: 1,510 Gy/hr) and exposed to the parasitoid S. endius at a proportion of one female parasitoid to five housefly pupae, during different periods after the irradiation. The results allow us to conclude that irradiation increase the acceptability period of the housefly pupae by the parasitoid. The best age to irradiate the housefly pupae was one day. (author)

  2. Inheritance of gynandromorphism in the parasitic wasp Nasonia vitripennis

    NARCIS (Netherlands)

    Kamping, Albert; Katju, Vaishali; Beukeboom, Leo W.; Werren, Jobn H.; Werren, John H.; Kaufman, T.C.

    The parasitic wasp Nasonia vitripennis has haplo-diploid sex determination. Males develop from unfertilized eggs and are haploid, whereas females develop from fertilized eggs and are diploid. Females and males can be easily distinguished by their morphology. A strain that produces individuals with

  3. Phenology of Spalangia endius Walker (Hymenoptera, Pteromalidae in pupae of Musca domestica Linnaeus (Diptera, Muscidae under laboratory conditions Fenologia de Spalangia endius Walker (Hymenoptera, Pteromalidae em pupas de Musca domestica Linnaeus (Diptera, Muscidae em condições de laboratório

    Directory of Open Access Journals (Sweden)

    Dani Furtado de Araújo

    2012-12-01

    Full Text Available This work describes the phenology of Spalangia endius Walker in pupae of Musca domestica Linnaeus under laboratory conditions. In order to understand the developmental cycle of Spalangia endius under laboratory conditions, 360 Musca domestica pupae aged from 24 to 48 hours were exposed to 15 S. endius pairs for a period of 24 hours at 26 ± 2ºC. These pupae were kept in a BOD incubator at the same temperature, with a relative humidity of Objetivando conhecer o ciclo de desenvolvimento de Spalangia endius sob condições de laboratório, 360 pupas de Musca domestica com idade de 24 a 48 horas foram expostas a 15 casais de S. endius por um período de 48 horas a 26 ± 2ºC. Estas pupas foram mantidas em BOD. Com mesma temperatura, umidade relativa <70% e com fotofase de 12 horas, onde diariamente dissecava-se 15 espécimes para avaliar o estágio e tempo de desenvolvimento do himenóptero. A fenologia permite concluir que S. endius apresenta um ciclo de desenvolvimento de 19 dias, cujo período de incubação foi de 24 horas, o desenvolvimento de larvas de S. endius ocorreu nos oito dias subsequentes nos quais uma série de alterações morfológicas foi observada. O estágio de pré-pupa deu-se no décimo dia onde cessa a movimentação e inicia a eliminação de mecônio. O estágio pupal ocorreu do décimo primeiro dia ao décimo nono, momento da emergência dos primeiros machos, já as fêmeas iniciaram a emergência aproximadamente 24 horas após. Estes resultados permitem avaliar aspectos da bionomia pormenorizada do desenvolvimento de S. endius para armazenar e programar a produção deste parasitóide, otimizando sua utilização como agente de controle biológico.

  4. Compliant walker

    Science.gov (United States)

    Kerley, James J. (Inventor); Eklund, Wayne D. (Inventor); Crane, J. Allen (Inventor)

    1992-01-01

    A compliant walker is provided for humans having limited use of their legs and lower back. It includes an upright wheel frame which at least partially surrounds an upright user wearing a partial body harness. It is attached to the frame by means of cable compliant apparatus consisting of sets of cable segments and angle bracket members connected between opposite side members of the frame and adjacent side portions of the harness. Novelty is believed to exist in the combination of a wheeled frame including a side support structure, a body harness, and compliance means connecting the body harness to the side support structure for flexibility holding and supporting a person in a substantially upright position when the user sags in the frame when taking weight off the lower extremities.

  5. Sequencing and de novo assembly of the transcriptome of the glassy-winged sharpshooter (Homalodisca vitripennis.

    Directory of Open Access Journals (Sweden)

    Raja Sekhar Nandety

    Full Text Available BACKGROUND: The glassy-winged sharpshooter Homalodisca vitripennis (Hemiptera: Cicadellidae, is a xylem-feeding leafhopper and important vector of the bacterium Xylella fastidiosa; the causal agent of Pierce's disease of grapevines. The functional complexity of the transcriptome of H. vitripennis has not been elucidated thus far. It is a necessary blueprint for an understanding of the development of H. vitripennis and for designing efficient biorational control strategies including those based on RNA interference. RESULTS: Here we elucidate and explore the transcriptome of adult H. vitripennis using high-throughput paired end deep sequencing and de novo assembly. A total of 32,803,656 paired-end reads were obtained with an average transcript length of 624 nucleotides. We assembled 32.9 Mb of the transcriptome of H. vitripennis that spanned across 47,265 loci and 52,708 transcripts. Comparison of our non-redundant database showed that 45% of the deduced proteins of H. vitripennis exhibit identity (e-value ≤1(-5 with known proteins. We assigned Gene Ontology (GO terms, Kyoto Encyclopedia of Genes and Genomes (KEGG annotations, and potential Pfam domains to each transcript isoform. In order to gain insight into the molecular basis of key regulatory genes of H. vitripennis, we characterized predicted proteins involved in the metabolism of juvenile hormone, and biogenesis of small RNAs (Dicer and Piwi sequences from the transcriptomic sequences. Analysis of transposable element sequences of H. vitripennis indicated that the genome is less expanded in comparison to many other insects with approximately 1% of the transcriptome carrying transposable elements. CONCLUSIONS: Our data significantly enhance the molecular resources available for future study and control of this economically important hemipteran. This transcriptional information not only provides a more nuanced understanding of the underlying biological and physiological mechanisms that

  6. Hymenoptera: Formicidae

    African Journals Online (AJOL)

    1990-05-15

    May 15, 1990 ... Supplemental Library User's Guide 1983 Edition. pp. 131-144. (Ed.) S. Ioyner. SAS Institute Incorporated, Cary,. North Carolina. CORBARA, B., LACHAUD, I. & FRESNEAU, D. 1989. Individual variability, social structure and division of labour in the ponerine ant, Ectatommo. ruidum Roger (Hymenoptera,.

  7. Sir Gilbert Thomas Walker

    Indian Academy of Sciences (India)

    He was educated at St Paul's School and later at the. Trinity College ... Walker spent the next 21 years doing research on monsoon ... J Bjerknes in 1969, 11 years after Walker's death. ... water-colours of landscapes at the Shimla Art Exhibition.

  8. Sir Gilbert Thomas Walker

    Indian Academy of Sciences (India)

    playa fundamental role in the variability of the earth's climate. Walker noted a tendency of ... Walker was however not able to ascertain the physical mechanism governing these oscillations. In the first two ... In 1927, he made the follow- ing prophetic statement: "There is, to-day, always a risk that specialists in two subjects,.

  9. Rapid Communication. Tamarixia monesus (Walker (Hym.: Eulophidae parasitoid of Bactericera tremblayi (Wagner, 1961 (Hemiptera: Triozidae in Iran

    Directory of Open Access Journals (Sweden)

    Lotfalizadeh Hossein

    2016-08-01

    Full Text Available Bactericera tremblayi (Wagner, 1961 (Hemiptera: Triozidae is reported on Brassica oleracea var. capitata (Brassicaceae in northwestern Iran. Tamarixia monesus (Walker (Hymenoptera: Chalcidoidea, Eulophidae was reared for the first time on B. tremblayi, and compared with Tamarixia tremblayi, another parasitoid of B. tremblayi. This is a new record of T. monesus from the Middle East.

  10. Families of vicious walkers

    International Nuclear Information System (INIS)

    Cardy, John; Katori, Makoto

    2003-01-01

    We consider a generalization of the vicious walker problem in which N random walkers in R d are grouped into p families. Using field-theoretic renormalization group methods we calculate the asymptotic behaviour of the probability that no pairs of walkers from different families have met up to time t. For d > 2, this is constant, but for d -α , which we compute to O(ε 2 ) in an expansion in ε = 2 - d. The second-order term depends on the ratios of the diffusivities of the different families. In two dimensions, we find a logarithmic decay (ln t) -α-bar and compute α-bar exactly

  11. Dandy-Walker Syndrome

    Science.gov (United States)

    ... treatment options. Other research indicates that mothers with diabetes and those with rubella (German measles) during pregnancy are more likely to have a child with Dandy-Walker syndrome. × What research is being ...

  12. Dandy Walker malformation

    African Journals Online (AJOL)

    PROF. EZECHUKWU

    2014-10-01

    - tion of Dandy walker syndrome to enhance early diagnosis, prompt intervention and better outcome ... tion of the central nervous system. It results from a .... Other predisposing factors include first trimester exposure to rubella ...

  13. Differential reproductive maturity between allopatric populations of Homalodisca vitripennis (Hemiptera: Cicadellidae) in California

    Science.gov (United States)

    Homalodisca vitripennis (Germar) is native to southeastern U.S. and northeastern Mexico. It was detected in southern California in the late 1980s and in the San Joaquin Valley in 1999, where it transmits the bacterium Xylella fastidiosa Wells et al. to grapevines and other crops. The reproductive ...

  14. Mating disruption of Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae) by playback of vibrational signals in vineyard trellis

    Science.gov (United States)

    BACKGROUND: Glassy-winged sharpshooter (GWSS), Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae), is an important vector of the bacterium Xylella fastidiosa, the causal agent of Pierce’s disease of grapevine. Area-wide applications of neonicotinoid insecticides have suppressed GWSS populati...

  15. Propagation of Homalodisca Coagulata Virus-01 via Homalodisca Vitripennis cell culture

    Science.gov (United States)

    The glassy-winged sharpshooter (Homalodisca vitripennis) is a highly vagile and polyphagous insect found throughout the southwestern United States. These insects are the predominant vectors of Xylella fastidiosa, a xylem-limited bacterium that is the causal agent of Pierce's disease (PD) of grapevin...

  16. Three friendly walkers

    Science.gov (United States)

    Jensen, Iwan

    2017-01-01

    More than 15 years ago Guttmann and Vöge (2002 J. Stat. Plan. Inference 101 107), introduced a model of friendly walkers. Since then it has remained unsolved. In this paper we provide the exact solution to a closely allied model which essentially only differs in the boundary conditions. The exact solution is expressed in terms of the reciprocal of the generating function for vicious walkers which is a D-finite function. However, ratios of D-finite functions are inherently not D-finite and in this case we prove that the friendly walkers generating function is the solution to a non-linear differential equation with polynomial coefficients, it is in other words D-algebraic. We find using numerically exact calculations a conjectured expression for the generating function of the original model as a ratio of a D-finite function and the generating function for vicious walkers. We obtain an expression for this D-finite function in terms of a {{}2}{{F}1} hypergeometric function with a rational pullback and its first and second derivatives. Dedicated to Tony Guttmann on the occasion of his 70th birthday.

  17. Dandy-Walker Malformation

    African Journals Online (AJOL)

    rme

    Dandy-Walker malformation is a rare congenital malformation and involves the cerebellum and fourth ventricle. The condition is characterized by agenesis or hypoplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle, and enlargement of the posterior fossa. A large number of concomitant problems may be ...

  18. Quincke random walkers

    Science.gov (United States)

    Pradillo, Gerardo; Heintz, Aneesh; Vlahovska, Petia

    2017-11-01

    The spontaneous rotation of a sphere in an applied uniform DC electric field (Quincke effect) has been utilized to engineer self-propelled particles: if the sphere is initially resting on a surface, it rolls. The Quincke rollers have been widely used as a model system to study collective behavior in ``active'' suspensions. If the applied field is DC, an isolated Quincke roller follows a straight line trajectory. In this talk, we discuss the design of a Quincke roller that executes a random-walk-like behavior. We utilize AC field - upon reversal of the field direction a fluctuation in the axis of rotation (which is degenerate in the plane perpendicular to the field and parallel to the surface) introduces randomness in the direction of motion. The MSD of an isolated Quincke walker depends on frequency, amplitude, and waveform of the electric field. Experiment and theory are compared. We also investigate the collective behavior of Quincke walkers,the transport of inert particles in a bath of Quincke walkers, and the spontaneous motion of a drop containing Quincke active particle. supported by NSF Grant CBET 1437545.

  19. Olfactory host finding, intermediate memory and its potential ecological adaptation in Nasonia vitripennis

    Science.gov (United States)

    Schurmann, Daria; Collatz, Jana; Hagenbucher, Steffen; Ruther, Joachim; Steidle, Johannes L. M.

    2009-03-01

    Associative learning of host-associated chemical cues was studied in Nasonia vitripennis, a parasitoid of fly pupae in nests of hole-nesting birds. When females encountered a fly pupa and performed one sequence of host recognition behaviour including drilling the ovipositor into the host in the presence of the artificial odour furfurylheptanoate (FFH), they were afterwards arrested by FFH in olfactometer experiments. The response vanished after 4 days and could be blocked after 3 days by feeding wasps with ethacrynic acid prior and after the training. This indicates the formation of an intermediate form of memory by one host experience in N. vitripennis. Interestingly, the trained wasps avoided odours that were not present during the host encounter, although naive wasps did not react to these odours. This unique behaviour probably causes wasps to focus during host searching on those chemical cues they have experienced in the host environment. Studies in nests of hole-nesting birds revealed that about 30% of all nests contained only one fly pupa, and laboratory studies showed that N. vitripennis females are able to parasitise around 100 fly pupae in their life. It is discussed that under these conditions, the formation of a non-permanent intermediate memory for host-associated odours after one host encounter is adaptive to avoid costs involved with formation and maintenance of memory for misleading cues. The demonstration of associative olfactory learning in N. vitripennis, the first parasitoid species with sequenced genome, opens the gate to study molecular mechanisms of memory formation and its ecological adaptation in parasitoids.

  20. DNA Methylation and Sex Allocation in the Parasitoid Wasp Nasonia vitripennis.

    Science.gov (United States)

    Cook, Nicola; Pannebakker, Bart A; Tauber, Eran; Shuker, David M

    2015-10-01

    The role of epigenetics in the control and evolution of behavior is being increasingly recognized. Here we test whether DNA methylation influences patterns of adaptive sex allocation in the parasitoid wasp Nasonia vitripennis. Female N. vitripennis allocate offspring sex broadly in line with local mate competition (LMC) theory. However, recent theory has highlighted how genomic conflict may influence sex allocation under LMC, conflict that requires parent-of-origin information to be retained by alleles through some form of epigenetic signal. We manipulated whole-genome DNA methylation in N. vitripennis females using the hypomethylating agent 5-aza-2'-deoxycytidine. Across two replicated experiments, we show that disruption of DNA methylation does not ablate the facultative sex allocation response of females, as sex ratios still vary with cofoundress number as in the classical theory. However, sex ratios are generally shifted upward when DNA methylation is disrupted. Our data are consistent with predictions from genomic conflict over sex allocation theory and suggest that sex ratios may be closer to the optimum for maternally inherited alleles.

  1. Genetics Home Reference: Dandy-Walker malformation

    Science.gov (United States)

    ... Twitter Home Health Conditions Dandy-Walker malformation Dandy-Walker malformation Printable PDF Open All Close All Enable ... to view the expand/collapse boxes. Description Dandy-Walker malformation affects brain development, primarily development of the ...

  2. Plant water stress effects on stylet probing behaviors of Homalodisca vitripennis (Hemiptera: Cicadellidae) associated with acquisition and inoculation of the bacterium Xylella fastidiosa

    Science.gov (United States)

    The glassy-winged sharpshooter, Homalodisca vitripennis, is a xylem fluid-ingesting leafhopper that transmits Xylella fastidiosa, the causal agent of several plant diseases in the Americas. While the role of plant water stress on the population density and dispersal of H. vitripennis has been studie...

  3. Identification of Novel and Conserved microRNAs in Homalodisca vitripennis, the Glassy-Winged Sharpshooter by Expression Profiling.

    Directory of Open Access Journals (Sweden)

    Raja Sekhar Nandety

    Full Text Available The glassy-winged sharpshooter (GWSS Homalodisca vitripennis (Hemiptera: Cicadellidae, is a xylem-feeding leafhopper and an important vector of the bacterium Xylella fastidiosa; the causal agent of Pierce's disease of grapevines. MicroRNAs are a class of small RNAs that play an important role in the functional development of various organisms including insects. In H. vitripennis, we identified microRNAs using high-throughput deep sequencing of adults followed by computational and manual annotation. A total of 14 novel microRNAs that are not found in the miRBase were identified from adult H. vitripennis. Conserved microRNAs were also found in our datasets. By comparison to our previously determined transcriptome sequence of H. vitripennis, we identified the potential targets of the microRNAs in the transcriptome. This microRNA profile information not only provides a more nuanced understanding of the biological and physiological mechanisms that govern gene expression in H. vitripennis, but may also lead to the identification of novel mechanisms for biorationally designed management strategies through the use of microRNAs.

  4. Parasitoidism of Chalcidid wasps (Hymenoptera, Chalcididae on Philornis sp. (Diptera, Muscidae

    Directory of Open Access Journals (Sweden)

    M. S. Couri

    Full Text Available Philornis Meinert larvae are known as parasites of birds, with coprophagous, semi-hematophagous or hematophagous habits. Biological data of the larvae of the fifty described species are still scarcely known. Here we describe some aspects of the parasitism of a species of Philornis on Thalurania glaucopis Gmelin (Trochilidae and record two species of Chalcididae (Hymenoptera parasitoids, Conura annulifera (Walker, 1864 and Brachymeria podagrica (Fabricius, 1787, reared from Philornis puparia.

  5. Fall prevention walker during rehabilitation

    Science.gov (United States)

    Tee, Kian Sek; E, Chun Zhi; Saim, Hashim; Zakaria, Wan Nurshazwani Wan; Khialdin, Safinaz Binti Mohd; Isa, Hazlita; Awad, M. I.; Soon, Chin Fhong

    2017-09-01

    This paper proposes on the design of a walker for the prevention of falling among elderlies or patients during rehabilitation whenever they use a walker to assist them. Fall happens due to impaired balance or gait problem. The assistive device is designed by applying stability concept and an accelerometric fall detection system is included. The accelerometric fall detection system acts as an alerting device that acquires body accelerometric data and detect fall. Recorded accelerometric data could be useful for further assessment. Structural strength of the walker was verified via iterations of simulation using finite element analysis, before being fabricated. Experiments were conducted to identify the fall patterns using accelerometric data. The design process and detection of fall pattern demonstrates the design of a walker that could support the user without fail and alerts the helper, thus salvaging the users from injuries due to fall and unattended situation.

  6. Vicious walkers in a potential

    International Nuclear Information System (INIS)

    Bray, Alan J; Winkler, Karen

    2004-01-01

    We consider N vicious walkers moving in one dimension in a one-body potential v(x). Using the backward Fokker-Planck equation we derive exact results for the asymptotic form of the survival probability Q(x, t) of vicious walkers initially located at (x 1 , ..., x N ) = x, when v(x) is an arbitrary attractive potential. Explicit results are given for a square-well potential with absorbing or reflecting boundary conditions at the walls, and for a harmonic potential with an absorbing or reflecting boundary at the origin and the walkers starting on the positive half line. By mapping the problem of N vicious walkers in zero potential onto the harmonic potential problem, we rederive the results by Fisher (1984 J. Stat. Phys. 34 667) and Krattenthaler et al (2000 J. Phys. A: Math. Gen. 33 8835) respectively for vicious walkers on an infinite line and on a semi-infinite line with an absorbing wall at the origin. This mapping also gives a new result for vicious walkers on a semi-infinite line with a reflecting boundary at the origin: Q(x,t) ∼ t N(N-1)/2

  7. Simple autonomous Mars walker

    Science.gov (United States)

    Larimer, Stanley J.; Lisec, Thomas R.; Spiessbach, Andrew J.

    1989-01-01

    Under a contract with NASA's Jet Propulsion Laboratory, Martin Marietta has developed several alternative rover concepts for unmanned exploration of the planet Mars. One of those concepts, the 'Walking Beam', is the subject of this paper. This concept was developed with the goal of achieving many of the capabilities of more sophisticated articulated-leg walkers with a much simpler, more robust, less computationally demanding and more power efficient design. It consists of two large-base tripods nested one within the other which alternately translate with respect to each other along a 5-meter beam to propel the vehicle. The semiautonomous navigation system relies on terrain geometry sensors and tacticle feedback from each foot to autonomously select a path which avoids hazards along a route designated from earth. Both mobility and navigation features of this concept are discussed including a top-level description of the vehicle's physical characteristics, deployment strategy, mobility elements, sensor suite, theory of operation, navigation and control processes, and estimated performance.

  8. Walker-Warburg syndrome

    Directory of Open Access Journals (Sweden)

    Schachter Harry

    2006-08-01

    Full Text Available Abstract Walker-Warburg Syndrome (WWS is a rare form of autosomal recessive congenital muscular dystrophy associated with brain and eye abnormalities. WWS has a worldwide distribution. The overall incidence is unknown but a survey in North-eastern Italy has reported an incidence rate of 1.2 per 100,000 live births. It is the most severe form of congenital muscular dystrophy with most children dying before the age of three years. WWS presents at birth with generalized hypotonia, muscle weakness, developmental delay with mental retardation and occasional seizures. It is associated with type II cobblestone lissencephaly, hydrocephalus, cerebellar malformations, eye abnormalities and congenital muscular dystrophy characterized by hypoglycosylation of α-dystroglycan. Several genes have been implicated in the etiology of WWS, and others are as yet unknown. Several mutations were found in the Protein O-Mannosyltransferase 1 and 2 (POMT1 and POMT2 genes, and one mutation was found in each of the fukutin and fukutin-related protein (FKRP genes. Laboratory investigations usually show elevated creatine kinase, myopathic/dystrophic muscle pathology and altered α-dystroglycan. Antenatal diagnosis is possible in families with known mutations. Prenatal ultrasound may be helpful for diagnosis in families where the molecular defect is unknown. No specific treatment is available. Management is only supportive and preventive.

  9. Design of a candidate vibrational signal for mating disruption against the glassy-winged sharpshooter, Homalodisca Vitripennis

    Science.gov (United States)

    The glassy-winged sharpshooter (GWSS), Homalodisca vitripennis, is an important pest of grapevines due to its ability to transmit Xylella fastidiosa, the causal agent of Pierce’s disease. GWSS mating communication is based on vibrational signals; therefore, vibrational mating disruption could be an ...

  10. Octopamine-like immunoreactive neurons in the brain and subesophageal ganglion of the parasitic wasps Nasonia vitripennis and N. giraulti

    NARCIS (Netherlands)

    Haverkamp, A.; Smid, H.M.

    2014-01-01

    Octopamine is an important neuromodulator in the insect nervous system, influencing memory formation, sensory perception and motor control. In this study, we compare the distribution of octopamine-like immunoreactive neurons in two parasitic wasp species of the Nasonia genus, N. vitripennis and N.

  11. Seasonal Population Dynamics of Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae) in Sweet Orange Trees Maintained under Continuous Deficit Irrigation

    Science.gov (United States)

    A two-year study was conducted in a citrus orchard [Citrus sinensis (L.) Osbeck cv. ‘Valencia’] to determine influence of plant water stress on population dynamics of glassy-winged sharpshooter (GWSS), Homalodisca vitripennis (Germar). Experimental treatments included irrigation at 100% of the crop...

  12. Cell cycle arrest in the jewel wasp Nasonia vitripennis in larval diapause.

    Science.gov (United States)

    Shimizu, Yuta; Mukai, Ayumu; Goto, Shin G

    2018-04-01

    Insects enter diapause to synchronise their life cycle with biotic and abiotic environmental conditions favourable for their development, reproduction, and survival. One of the most noticeable characteristics of diapause is the blockage of ontogeny. Although this blockage should occur with the cessation of cellular proliferation, i.e. cell cycle arrest, it was confirmed only in a few insect species and information on the molecular pathways involved in cell cycle arrest is limited. In the present study, we investigated developmental and cell cycle arrest in diapause larvae of the jewel wasp Nasonia vitripennis. Developmental and cell cycle arrest occur in the early fourth instar larval stage of N. vitripennis under short days. By entering diapause, the S fraction of the cell cycle disappears and approximately 80% and 20% of cells arrest their cell cycle in the G0/G1 and G2 phases, respectively. We further investigated expression of cell cycle regulatory genes and some housekeeping genes to dissect molecular mechanisms underlying the cell cycle arrest. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Madame Kara Walker, notre artiste

    Directory of Open Access Journals (Sweden)

    Riché Deianne Richardson

    2008-01-01

    Full Text Available « Mon Ennemi, Mon Frère, Mon Bourreau, Mon Amour, » the epic exhibition at ARC/ Musée d’art moderne de la ville de Paris running from 20 June to 9 September, reveals the creative genius and vision of the artist Kara Walker, who was born in Stockton, California in 1969. The show is her most comprehensive one yet in Europe and includes the form that Walker has uniquely developed and for which she is best known, cut-out black silhouettes that are sometimes small and at other times gigantic and r...

  14. 21 CFR 890.3825 - Mechanical walker.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mechanical walker. 890.3825 Section 890.3825 Food... DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3825 Mechanical walker. (a) Identification. A mechanical walker is a four-legged device with a metal frame intended for medical purposes to...

  15. A novel approach to eliminate Wolbachia infections in Nasonia vitripennis revealed different antibiotic resistance between two bacterial strains.

    Science.gov (United States)

    Liu, Hai-Yang; Wang, Yan-Kun; Zhi, Cong-Cong; Xiao, Jin-Hua; Huang, Da-Wei

    2014-06-01

    Wolbachia are widespread in insects and can manipulate host reproduction. Nasonia vitripennis is a widely studied organism with a very high prevalence of Wolbachia infection. To study the effect of Wolbachia infection in Nasonia spp., it is important to obtain noninfected individuals by artificial methods. Current methods that employ sugar water-containing antibiotics can successfully eliminate Wolbachia from the parasitic wasps; however, treatment of at least three generations is required. Here, we describe a novel, feasible, and effective approach to eliminate Wolbachia from N. vitripennis by feeding fly pupae continuously offering antibiotics to Nasonia populations, which shortened the time to eliminate the pathogens to two generations. Additionally, the Wolbachia Uni and CauB strains have obviously different rifampicin-resistance abilities, which is a previously unknown phenomenon. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  16. Vicious walkers and hook Young tableaux

    International Nuclear Information System (INIS)

    Hikami, Kazuhiro; Imamura, Takashi

    2003-01-01

    We consider a generalization of the vicious walker model. Using a bijection map between the path configuration of the non-intersecting random walkers and the hook Young diagram, we compute the probability concerning the number of movements of the walker. Applying the saddle point method, we reveal that the scaling limit gives the Tracy-Widom distribution, which is the same with the limit distribution of the largest eigenvalues of the Gaussian unitary ensemble

  17. Genomics and peptidomics of neuropeptides and protein hormones present in the parasitic wasp Nasonia vitripennis

    DEFF Research Database (Denmark)

    Hauser, Frank; Neupert, Susanne; Williamson, Michael

    2010-01-01

    Neuropeptides and protein hormones constitute a very important group of signaling molecules, regulating central physiological processes such as reproduction, development, and behavior. Using a bioinformatics approach, we screened the recently sequenced genome of the parasitic wasp, Nasonia vitrip...... melanogaster, Aedes aegypti (both Diptera), Bombyx mori (Lepidoptera), Tribolium castaneum (Coleoptera), Apis mellifera (Hymenoptera), and Acyrthosiphon pisum (Hemiptera). This lower number of neuropeptide genes might be related to Nasonia's parasitic life....

  18. Recent progress on DNA based walkers.

    Science.gov (United States)

    Pan, Jing; Li, Feiran; Cha, Tae-Gon; Chen, Haorong; Choi, Jong Hyun

    2015-08-01

    DNA based synthetic molecular walkers are reminiscent of biological protein motors. They are powered by hybridization with fuel strands, environment induced conformational transitions, and covalent chemistry of oligonucleotides. Recent developments in experimental techniques enable direct observation of individual walkers with high temporal and spatial resolution. The functionalities of state-of-the-art DNA walker systems can thus be analyzed for various applications. Herein we review recent progress on DNA walker principles and characterization methods, and evaluate various aspects of their functions for future applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. CEPF Western Ghats Special Series : Parasitoids (Hymenoptera of xylophagous beetles (Coleoptera attacking dead wood in southern Western Ghats, Kerala, India, with descriptions of two new species

    Directory of Open Access Journals (Sweden)

    P.M. Sureshan

    2013-05-01

    Full Text Available An account is given of four species of Hymenoptera parasitoids probably of the wood boring beetle Clytocera chinospila Gahan (Coleoptera: Cerambycidae from Chinnar Wildlife Sanctuary, southern Western Ghats, Kerala. Two new hymenopteran species, Eurytoma chinnarensis (Eurytomidae and Foenatopus idukkiensis (Stephanidae are described. Solenura ania Walker (Pteromalidae is reported for the first time from Kerala and Western Ghats with a new host record, and Doryctus sp. (Braconidae is reported here.

  20. Averaging Robertson-Walker cosmologies

    International Nuclear Information System (INIS)

    Brown, Iain A.; Robbers, Georg; Behrend, Juliane

    2009-01-01

    The cosmological backreaction arises when one directly averages the Einstein equations to recover an effective Robertson-Walker cosmology, rather than assuming a background a priori. While usually discussed in the context of dark energy, strictly speaking any cosmological model should be recovered from such a procedure. We apply the scalar spatial averaging formalism for the first time to linear Robertson-Walker universes containing matter, radiation and dark energy. The formalism employed is general and incorporates systems of multiple fluids with ease, allowing us to consider quantitatively the universe from deep radiation domination up to the present day in a natural, unified manner. Employing modified Boltzmann codes we evaluate numerically the discrepancies between the assumed and the averaged behaviour arising from the quadratic terms, finding the largest deviations for an Einstein-de Sitter universe, increasing rapidly with Hubble rate to a 0.01% effect for h = 0.701. For the ΛCDM concordance model, the backreaction is of the order of Ω eff 0 ≈ 4 × 10 −6 , with those for dark energy models being within a factor of two or three. The impacts at recombination are of the order of 10 −8 and those in deep radiation domination asymptote to a constant value. While the effective equations of state of the backreactions in Einstein-de Sitter, concordance and quintessence models are generally dust-like, a backreaction with an equation of state w eff < −1/3 can be found for strongly phantom models

  1. How the Venom from the Ectoparasitoid Wasp Nasonia vitripennis Exhibits Anti-Inflammatory Properties on Mammalian Cell Lines

    Science.gov (United States)

    Danneels, Ellen L.; Gerlo, Sarah; Heyninck, Karen; Van Craenenbroeck, Kathleen; De Bosscher, Karolien; Haegeman, Guy; de Graaf, Dirk C.

    2014-01-01

    With more than 150,000 species, parasitoids are a large group of hymenopteran insects that inject venom into and then lay their eggs in or on other insects, eventually killing the hosts. Their venoms have evolved into different mechanisms for manipulating host immunity, physiology and behavior in such a way that enhance development of the parasitoid young. The venom from the ectoparasitoid Nasonia vitripennis inhibits the immune system in its host organism in order to protect their offspring from elimination. Since the major innate immune pathways in insects, the Toll and Imd pathways, are homologous to the NF-κB pathway in mammals, we were interested in whether a similar immune suppression seen in insects could be elicited in a mammalian cell system. A well characterized NF-κB reporter gene assay in fibrosarcoma cells showed a dose-dependent inhibition of NF-κB signaling caused by the venom. In line with this NF-κB inhibitory action, N. vitripennis venom dampened the expression of IL-6, a prototypical proinflammatory cytokine, from LPS-treated macrophages. The venom also inhibited the expression of two NF-κB target genes, IκBα and A20, that act in a negative feedback loop to prevent excessive NF-κB activity. Surprisingly, we did not detect any effect of the venom on the early events in the canonical NF-κB activation pathway, leading to NF-κB nuclear translocation, which was unaltered in venom-treated cells. The MAP kinases ERK, p38 and JNK are other crucial regulators of immune responses. We observed that venom treatment did not affect p38 and ERK activation, but induced a prolonged JNK activation. In summary, our data indicate that venom from N. vitripennis inhibits NF-κB signaling in mammalian cells. We identify venom-induced up regulation of the glucocorticoid receptor-regulated GILZ as a most likely molecular mediator for this inhibition. PMID:24821138

  2. Maternal provision of transformer-2 is required for female development and embryo viability in the wasp Nasonia vitripennis.

    Science.gov (United States)

    Geuverink, Elzemiek; Rensink, Anna H; Rondeel, Inge; Beukeboom, Leo W; van de Zande, Louis; Verhulst, Eveline C

    2017-11-01

    In insect sex determination a primary signal starts the genetic sex determination cascade that, in most insect orders, is subsequently transduced down the cascade by a transformer (tra) ortholog. Only a female-specifically spliced tra mRNA yields a functional TRA-protein that forms a complex with TRA2, encoded by a transformer-2 (tra2) ortholog, to act as a sex specific splicing regulator of the downstream transcription factors doublesex (dsx) and fruitless (fru). Here, we identify the tra2 ortholog of the haplodiploid parasitoid wasp N. vitripennis (Nv-tra2) and confirm its function in N. vitripennis sex determination. Knock down of Nv-tra2 by parental RNA interference (pRNAi) results in complete sex reversal of diploid offspring from female to male, indicating the requirement of Nv-tra2 for female sex determination. As Nv-tra2 pRNAi leads to frequent lethality in early developmental stages, maternal provision of Nv-tra2 transcripts is apparently also required for another, non-sex determining function during embryogenesis. In addition, lethality following Nv-tra2 pRNAi appears more pronounced in diploid than in haploid offspring. This diploid lethal effect was also observed following Nv-tra pRNAi, which served as a positive control in our experiments. As diploid embryos from fertilized eggs have a paternal chromosome set in addition to the maternal one, this suggests that either the presence of this paternal chromosome set or the dosage effect resulting from the diploid state is incompatible with the induced male development in N. vitripennis caused by either Nv-tra2 or Nv-tra pRNAi. The role of Nv-tra2 in activating the female sex determination pathway yields more insight into the sex determination mechanism of Nasonia. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Beliefs about the use of baby walkers

    OpenAIRE

    Chagas,Paula S. C.; Mancini,Marisa C.; Tirado,Marcella G. A.; Megale,Luiz; Sampaio,Rosana F.

    2011-01-01

    OBJECTIVES: To understand the opinion of the parents about the baby walker and compare the age of gait acquisition between infants that used a walker and those that did not. METHODS: In this quali-quantitative study, an interview involving a semi-structured questionnaire was carried out with 26 parents, 14 of whose infants used the equipment (BWG) and 12 of whose infants did not (NBWG) prior to gait acquisition. After extensive content analysis, categories for interpreting the results emerged...

  4. Plant water stress effects on stylet probing behaviors of Homalodisca vitripennis (Hemiptera: Cicadellidae) associated with acquisition and inoculation of the bacterium Xylella fastidiosa.

    Science.gov (United States)

    Krugner, Rodrigo; Backus, Elaine A

    2014-02-01

    ABSTRACT The glassy-winged sharpshooter, Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae), is a xylem fluid-ingesting leafhopper that transmits Xylella fastidiosa Wells et al., a plant-infecting bacterium that causes several plant diseases in the Americas. Although the role of plant water stress on the population density and dispersal ofH. vitripennis has been studied, nothing is known about the effects of plant water stress on the transmission of X. fastidiosa by H. vitripennis. A laboratory study was conducted to determine the influence of plant water stress on the sharpshooter stylet probing behaviors associated with the acquisition and inoculation of X. fastidiosa. Electrical penetration graph was used to monitor H. vitripennis feeding behaviors for 20-h periods on citrus [Citrus sinensis (L.) Osbeck] and almond [Prunus dulcis (Miller) D.A. Webb] plants subjected to levels of water stress. Adult H. vitripennis successfully located xylem vessels, then performed behaviors related to the evaluation of the xylem cell and fluid, and finally ingested xylem fluid from citrus and almond plants under the tested fluid tensions ranging from -5.5 to -33.0 bars and -6.0 to -24.5 bars, respectively. In general, long and frequent feeding events associated with the acquisition and inoculation of X. fastidiosa were observed only in fully irrigated plants (i.e., >-10 bars), which suggests that even low levels of plant water stress may reduce the spread of X. fastidiosa. Results provided insights to disease epidemiology and support the hypothesis that application of regulated deficit irrigation has the potential to reduce the incidence of diseases caused by X.fastidiosa by reducing the number of vectors and by decreasing pathogen transmission efficiency.

  5. Diagnosis of Hymenoptera venom allergy

    NARCIS (Netherlands)

    Bilo, BM; Rueff, F; Mosbech, H; Bonifazi, F; Oude Elberink, JNG

    2005-01-01

    The purpose of diagnostic procedure is to classify a sting reaction by history, identify the underlying pathogenetic mechanism, and identify the offending insect. Diagnosis of Hymenoptera venom allergy thus forms the basis for the treatment. In the central and northern Europe vespid (mainly Vespula

  6. Sex determination in the Hymenoptera

    NARCIS (Netherlands)

    Heimpel, George E.; de Boer, Jetske G.

    2008-01-01

    The dominant and ancestral mode of sex determination in the Hymenoptera is arrhenotokous parthenogenesis, in which diploid females develop from fertilized eggs and haploid males develop from unfertilized eggs. We discuss recent progress in the understanding of the genetic and cytoplasmic mechanisms

  7. Enkele bijzondere bijenwaarnemingen (Hymenoptera: Apidae)

    NARCIS (Netherlands)

    Raemakers, I.P.

    2000-01-01

    Some interesting records on Dutch bees (Hymenoptera: Apidae) The publication of the preliminary atlas of Dutch bees (Peeters et al. 1999) has stimulated many specialists in their mapping activity. The author reports several interesting new distribution records on ten bee-species in 1999. The Dutch

  8. Baby walkers--health visitors' current practice, attitudes and knowledge.

    Science.gov (United States)

    Kendrick, Denise; Illingworth, Rachel; Hapgood, Rhydian; Woods, Amanda J; Collier, Jacqueline

    2003-09-01

    Baby walkers are a commonly used item of nursery equipment. Between 12% and 50% of parents whose infant uses a walker report that their child has suffered a walker-related injury. Health visitors' knowledge, attitudes and practice with regard to walkers and related health education has not been explored so far. The aim of the study was to describe health visitors' knowledge of walkers and walker-related injuries, their attitudes towards walkers and current practice with regard to walker health education, and to examine the relationship between knowledge and attitudes and knowledge and practice. A survey was carried out with 64 health visitors prior to participation in a randomized controlled trial assessing the effectiveness of an educational package in reducing baby walker use. The response rate was 95%. Half of the health visitors always discussed walkers postnatally, most frequently at the 6-9 month check. Most did not usually discuss the frequency of walker-related injuries. Most had negative attitudes towards walkers, but believed that parents hold positive attitudes to them and that it is hard to persuade parents not to use them. Health visitors had a limited knowledge of walker use and walker-related injuries. Those giving advice on walkers most often had higher knowledge scores than those giving advice less often (P = 0.03). Those with higher knowledge scores held more negative attitudes towards walkers (rs = 0.29, P = 0.023) and believed parents to have more positive attitudes towards walkers (rs = -0.49, P negotiating alternatives to their use. The provision of audio-visual aids for discussing walkers might also be helpful.

  9. Raalin, a transcript enriched in the honey bee brain, is a remnant of genomic rearrangement in Hymenoptera.

    Science.gov (United States)

    Tirosh, Y; Morpurgo, N; Cohen, M; Linial, M; Bloch, G

    2012-06-01

    We identified a predicted compact cysteine-rich sequence in the honey bee genome that we called 'Raalin'. Raalin transcripts are enriched in the brain of adult honey bee workers and drones, with only minimum expression in other tissues or in pre-adult stages. Open-reading frame (ORF) homologues of Raalin were identified in the transcriptomes of fruit flies, mosquitoes and moths. The Raalin-like gene from Drosophila melanogaster encodes for a short secreted protein that is maximally expressed in the adult brain with negligible expression in other tissues or pre-imaginal stages. Raalin-like sequences have also been found in the recently sequenced genomes of six ant species, but not in the jewel wasp Nasonia vitripennis. As in the honey bee, the Raalin-like sequences of ants do not have an ORF. A comparison of the genome region containing Raalin in the genomes of bees, ants and the wasp provides evolutionary support for an extensive genome rearrangement in this sequence. Our analyses identify a new family of ancient cysteine-rich short sequences in insects in which insertions and genome rearrangements may have disrupted this locus in the branch leading to the Hymenoptera. The regulated expression of this transcript suggests that it has a brain-specific function. © 2012 The Authors. Insect Molecular Biology © 2012 The Royal Entomological Society.

  10. Vicious random walkers in the limit of a large number of walkers

    International Nuclear Information System (INIS)

    Forrester, P.J.

    1989-01-01

    The vicious random walker problem on a line is studied in the limit of a large number of walkers. The multidimensional integral representing the probability that the p walkers will survive a time t (denoted P t (p) ) is shown to be analogous to the partition function of a particular one-component Coulomb gas. By assuming the existence of the thermodynamic limit for the Coulomb gas, one can deduce asymptotic formulas for P t (p) in the large-p, large-t limit. A straightforward analysis gives rigorous asymptotic formulas for the probability that after a time t the walkers are in their initial configuration (this event is termed a reunion). Consequently, asymptotic formulas for the conditional probability of a reunion, given that all walkers survive, are derived. Also, an asymptotic formula for the conditional probability density that any walker will arrive at a particular point in time t, given that all p walkers survive, is calculated in the limit t >> p

  11. Transcriptome profiling of Nasonia vitripennis testis reveals novel transcripts expressed from the selfish B chromosome, paternal sex ratio.

    Science.gov (United States)

    Akbari, Omar S; Antoshechkin, Igor; Hay, Bruce A; Ferree, Patrick M

    2013-09-04

    A widespread phenomenon in nature is sex ratio distortion of arthropod populations caused by microbial and genetic parasites. Currently little is known about how these agents alter host developmental processes to favor one sex or the other. The paternal sex ratio (PSR) chromosome is a nonessential, paternally transmitted centric fragment that segregates in natural populations of the jewel wasp, Nasonia vitripennis. To persist, PSR is thought to modify the hereditary material of the developing sperm, with the result that all nuclear DNA other than the PSR chromosome is destroyed shortly after fertilization. This results in the conversion of a fertilized embryo--normally a female--into a male, thereby insuring transmission of the "selfish" PSR chromosome, and simultaneously leading to wasp populations that are male-biased. To begin to understand this system at the mechanistic level, we carried out transcriptional profiling of testis from WT and PSR-carrying males. We identified a number of transcripts that are differentially expressed between these conditions. We also discovered nine transcripts that are uniquely expressed from the PSR chromosome. Four of these PSR-specific transcripts encode putative proteins, whereas the others have very short open reading frames and no homology to known proteins, suggesting that they are long noncoding RNAs. We propose several different models for how these transcripts could facilitate PSR-dependent effects. Our analyses also revealed 15.71 MB of novel transcribed regions in the N. vitripennis genome, thus increasing the current annotation of total transcribed regions by 53.4%. Finally, we detected expression of multiple meiosis-related genes in the wasp testis, despite the lack of conventional meiosis in the male sex.

  12. A walker used as a lifting device.

    Science.gov (United States)

    Glimskär, Bo; Hjalmarson, Jenny; Lundberg, Stefan; Larsson, Tore

    2014-05-01

    To develop assistive technology that would help an older person to arise from a kneeling position to a standing one. Developing a prototype, based on an inclusive design and then testing the prototype to verify the approach. The prototype was subsequently tested by a panel of 20 elderly users. These tests were observed and filmed. Participants' experiences of being lifted with the elevation seat were registered with the VIDAR ergonomic assessment system. None of the 20 participants used a walker at that time. In response to a question of whether, assuming they might have to use a walker in the future, they thought that a walker with an elevating seat would be helpful, 18 said that it would. Two of the participants did not believe that they would ever have to use a walker. A simple assistive technology such as a walker equipped with an elevating seat would in many of these cases simplify matters and reduce the distress of people who fall often. In addition, such a device can allow people who fall often to live in their homes longer. For caregivers dealing frequently with people who fall, this assistive device can contribute to decreasing occupational injuries. Development of a lifting device that can help people raise themselves up entirely on their own, or with minimal assistance, would be a revolutionary step for the individual. Lifting devices in use today requires much more extensive assistance from home helpers or others and due to the risk of injuries it is a great value for the helpers that easy to use devices develops. A walker equipped with an elevating seat could even provide a potential for people to stay in their homes longer.

  13. Beliefs about the use of baby walkers.

    Science.gov (United States)

    Chagas, Paula S C; Mancini, Marisa C; Tirado, Marcella G A; Megale, Luiz; Sampaio, Rosana F

    2011-01-01

    To understand the opinion of the parents about the baby walker and compare the age of gait acquisition between infants that used a walker and those that did not. In this quali-quantitative study, an interview involving a semi-structured questionnaire was carried out with 26 parents, 14 of whose infants used the equipment (BWG) and 12 of whose infants did not (NBWG) prior to gait acquisition. After extensive content analysis, categories for interpreting the results emerged. For data triangulation, the age of gait acquisition was documented by weekly telephone contact. Student's t-test was used for comparison between groups with a significance level of α=0.05. The following categories were identified in the parents' reports: a) information about the baby walker; b) doubt/decision to use it vs. certainty about not using it; c) beliefs about the use of a baby-walker; and d) benefits and harm from use. The age of independent gait acquisition did not differ between groups (p=0.837): BWG initiated gait at 376.17 (SD=32.62) days and NBWG did so at 378.75 (SD=27.99) days. The beliefs and feelings that permeate the decision to use a baby walker illustrate the different rationales adopted by parents about the role of this equipment in the child's development of gait and autonomy. The use of a baby walker did not influence the age of gait acquisition. The results broaden the understanding of choices that influence child-rearing practices prior to gait acquisition.

  14. Curvature properties of four-dimensional Walker metrics

    International Nuclear Information System (INIS)

    Chaichi, M; Garcia-Rio, E; Matsushita, Y

    2005-01-01

    A Walker n-manifold is a semi-Riemannian manifold, which admits a field of parallel null r-planes, r ≤ n/2. In the present paper we study curvature properties of a Walker 4-manifold (M, g) which admits a field of parallel null 2-planes. The metric g is necessarily of neutral signature (+ + - -). Such a Walker 4-manifold is the lowest dimensional example not of Lorentz type. There are three functions of coordinates which define a Walker metric. Some recent work shows that a Walker 4-manifold of restricted type whose metric is characterized by two functions exhibits a large variety of symplectic structures, Hermitian structures, Kaehler structures, etc. For such a restricted Walker 4-manifold, we shall study mainly curvature properties, e.g., conditions for a Walker metric to be Einstein, Osserman, or locally conformally flat, etc. One of our main results is the exact solutions to the Einstein equations for a restricted Walker 4-manifold

  15. 75 FR 38833 - Walker River Basin Acquisition Program

    Science.gov (United States)

    2010-07-06

    ... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Walker River Basin Acquisition Program AGENCY... (Reclamation) is canceling work on the Environmental Impact Statement (EIS) for the Walker River Basin... Walker River, primarily for irrigated agriculture, have resulted in a steadily declining surface...

  16. 78 FR 48301 - Establishment of Class E Airspace; Walker, MN

    Science.gov (United States)

    2013-08-08

    ...-0266; Airspace Docket No. 13-AGL-11] Establishment of Class E Airspace; Walker, MN AGENCY: Federal... at Walker, MN. Controlled airspace is necessary to accommodate new Area Navigation (RNAV) Standard Instrument Approach Procedures at Walker Municipal Airport. The FAA is taking this action to enhance the...

  17. Obituary: Robert Mowbray Walker, 1929-2004

    Science.gov (United States)

    Schoenherr, Neil T.

    2004-12-01

    Robert M. Walker, PhD, Professor of Physics in Arts & Sciences and a faculty fellow of the McDonnell Center for the Space Sciences, died of stomach cancer Thursday, 12 February 2004, in Brussels, Belgium. He was 75. Walker worked on the frontiers of space research for more than four decades. Robert Walker was born in Philadelphia on 6 February 1929. His mother was Dorothy Potter and he considered Roger Potter his father though he was not his biological father. His early years were spent in New York City and in upstate New York. He attended the Bronx High School of Science, earned his BS in physics from Union College and in 1954, he received his PhD in particle physics from Yale University. He subsequently joined the General Electric Laboratory in Schenectady, New York where he studied the radiation effects in solids. His work on defects in irradiated copper is still regarded as the definitive work on the topic. In the early 1960s, Walker's discovery of fossil nuclear particle tracks in minerals was instrumental to new developments in geo-chronology and cosmic ray physics. In particular, his discovery of tracks from nuclei heavier than iron opened a new frontier of cosmic ray physics. He subsequently pioneered the use of plastics to detect and count such nuclei in cosmic ray balloon flights. Beginning in 1966, when he moved to Washington University and became the first McDonnell Professor of Physics, his research interests turned more toward space physics. He was the inaugural director of the McDonnell Center, which was established in 1975 by a gift from aerospace pioneer James S. McDonnell. Walker was a member of the NASA committee that allocated samples of the first returned lunar materials, and his laboratory led the way in deciphering their record of lunar, solar system and galactic evolution. Together with Ghislaine Crozaz and other colleagues, Walker made path breaking laboratory studies of the first moon rocks revealing the history of solar radiation and

  18. A walker with a device of partial suspension for patients with gait disturbance: body weight supported walker.

    Science.gov (United States)

    Ochi, Mitsuhiro; Makino, Kenichiro; Wada, Futoshi; Saeki, Satoru; Hachisuka, Kenji

    2009-09-01

    We developed a walker, the Body Weight Supported (BWS) Walker, with a device of partial suspension for patients with gait disturbance. It consists of a light frame with casters, a harness, and a winch system. One therapist alone can perform gait training safely with the BWS Walker without any additional physical load, even if a patient has severe gait disturbance, and the therapist can concentrate on evaluating and improving the patient' s standing balance and gait pattern. Because the BWS Walker is less expensive, simpler, and easier to operate than other BWS systems, we believe the BWS Walker can be widely applicable in training for patients with severe and moderate gait disturbance.

  19. Neutral signature Walker-VSI metrics

    International Nuclear Information System (INIS)

    Coley, A; McNutt, D; Musoke, N; Brooks, D; Hervik, S

    2014-01-01

    We will construct explicit examples of four-dimensional neutral signature Walker (but not necessarily degenerate Kundt) spaces for which all of the polynomial scalar curvature invariants vanish. We then investigate the properties of some particular subclasses of Ricci flat spaces. We also briefly describe some four-dimensional neutral signature Einstein spaces for which all of the polynomial scalar curvature invariants are constant. (paper)

  20. Using walker during walking: a pilot study for health elder.

    Science.gov (United States)

    Po-Chan, Yeh; Cherng-Yee, Leung

    2012-01-01

    Walker operation completely relies on the walker handle, however most marketed walkers possess two horizontal handles. Several researchers have suggested that horizontal handles might lead to wrist injury. Therefore, the purpose of this study is to assess the relevant design aspects of walker for elderly people. 28 elders participated in this study; when the experiment was started, subject walked on the tile for 3 meter distance twice by using walker. Data for analysis were selected at the corresponding wrist deviation and vertical force. The results showed that during walker using, the mean wrist deviation was greater than zero. The largest vertical force is significantly larger than the smallest one, and different wrist deviation occurred at three phases, the largest wrist deviation while raising walker is larger than the smallest one, however, no significant different was found between the largest and smallest wrist deviation while pressing walker. No significant correlation occurred between weight and wrist deviation. The correlation between weight and vertical force was significantly positive. With wrist deviation walker use may cause injury to upper-limb, however wrists remain in a neutral position during hand movement to prevent damage. The findings of this study should improve the design of walker handles to reduce the wrist deviations of users.

  1. Auditory perception of a human walker.

    Science.gov (United States)

    Cottrell, David; Campbell, Megan E J

    2014-01-01

    When one hears footsteps in the hall, one is able to instantly recognise it as a person: this is an everyday example of auditory biological motion perception. Despite the familiarity of this experience, research into this phenomenon is in its infancy compared with visual biological motion perception. Here, two experiments explored sensitivity to, and recognition of, auditory stimuli of biological and nonbiological origin. We hypothesised that the cadence of a walker gives rise to a temporal pattern of impact sounds that facilitates the recognition of human motion from auditory stimuli alone. First a series of detection tasks compared sensitivity with three carefully matched impact sounds: footsteps, a ball bouncing, and drumbeats. Unexpectedly, participants were no more sensitive to footsteps than to impact sounds of nonbiological origin. In the second experiment participants made discriminations between pairs of the same stimuli, in a series of recognition tasks in which the temporal pattern of impact sounds was manipulated to be either that of a walker or the pattern more typical of the source event (a ball bouncing or a drumbeat). Under these conditions, there was evidence that both temporal and nontemporal cues were important in recognising theses stimuli. It is proposed that the interval between footsteps, which reflects a walker's cadence, is a cue for the recognition of the sounds of a human walking.

  2. Egg Parasitoids of Proconiini (Hemiptera: Cicadellidae) in Northwestern Mexico, with Description of a New Species of Gonatocerus (Hymenoptera: Mymaridae)

    Science.gov (United States)

    Triapitsyn, Serguei V.; Bernal, Julio S.

    2009-01-01

    Nine species of Mymaridae and Trichogrammatidae parasitic on eggs of Proconiini sharpshooters (Cicadellidae: Cicadellinae) were collected in northwestern Mexico in relation to neoclassical biological control efforts against glassy-winged sharpshooter, Homalodisca vitripennis (Germar), in California. Gonatocerus chula Triapitsyn and Bernal sp. n., which belongs to the ater species group of Gonatocerus Nees (Mymaridae), is described. Specimens of G. chula sp. n. were reared from eggs of the smoke-tree sharpshooter, Homalodisca liturata Ball, on jojoba [Simmondsia chinensis (Link) C. K. Schneider] leaves collected in central Sonora state, Mexico. Also given are new data on other egg parasitoids of Homalodisca spp. and Oncometopia spp. in Sinaloa and Sonora states, Mexico, including Gonatocerus atriclavus Girault, G. morrilli (Howard), and G. novifasciatus Girault, and the Trichogrammatidae Burksiella sp(p)., Ittys sp., Pseudoligosita sp., Ufens ceratus Owen, and U. principalis Owen. For the first time, a species of Ittys is recorded from eggs of Proconiini, and U. principalis from Mexico. Colonies of G. atriclavus, G. novifasciatus and Pseudoligosita sp. were successfully established in a quarantine laboratory at University of California, Riverside, on eggs of the glassy-winged sharpshooter. These three parasitoid species had never been reared under laboratory conditions. In addition, seven species of Proconiini were collected in central and northwestern Mexico: Cyrtodisca major (Signoret), Homalodisca insolita (Walker), H. liturata Ball, Oncometopia sp. cf. clarior (Walker), O. sp. cf. trilobata Melichar, O. (Similitopia) sp., and Phera centrolineata (Signoret). Oncometopia sp. cf. clarior, O. sp. cf. trilobata, and O. (Similitopia) sp. appeared to be undescribed species. PMID:19611244

  3. Water Budgets of the Walker River Basin and Walker Lake, California and Nevada

    Science.gov (United States)

    Lopes, Thomas J.; Allander, Kip K.

    2009-01-01

    The Walker River is the main source of inflow to Walker Lake, a closed-basin lake in west-central Nevada. The only outflow from Walker Lake is evaporation from the lake surface. Between 1882 and 2008, upstream agricultural diversions resulted in a lake-level decline of more than 150 feet and storage loss of 7,400,000 acre-feet. Evaporative concentration increased dissolved solids from 2,500 to 17,000 milligrams per liter. The increase in salinity threatens the survival of the Lahontan cutthroat trout, a native species listed as threatened under the Endangered Species Act. This report describes streamflow in the Walker River basin and an updated water budget of Walker Lake with emphasis on the lower Walker River basin downstream from Wabuska, Nevada. Water budgets are based on average annual flows for a 30-year period (1971-2000). Total surface-water inflow to the upper Walker River basin upstream from Wabuska was estimated to be 387,000 acre-feet per year (acre-ft/yr). About 223,000 acre-ft/yr (58 percent) is from the West Fork of the Walker River; 145,000 acre-ft/yr (37 percent) is from the East Fork of the Walker River; 17,000 acre-ft/yr (4 percent) is from the Sweetwater Range; and 2,000 acre-ft/yr (less than 1 percent) is from the Bodie Mountains, Pine Grove Hills, and western Wassuk Range. Outflow from the upper Walker River basin is 138,000 acre-ft/yr at Wabuska. About 249,000 acre-ft/yr (64 percent) of inflow is diverted for irrigation, transpired by riparian vegetation, evaporates from lakes and reservoirs, and recharges alluvial aquifers. Stream losses in Antelope, Smith, and Bridgeport Valleys are due to evaporation from reservoirs and agricultural diversions with negligible stream infiltration or riparian evapotranspiration. Diversion rates in Antelope and Smith Valleys were estimated to be 3.0 feet per year (ft/yr) in each valley. Irrigated fields receive an additional 0.8 ft of precipitation, groundwater pumpage, or both for a total applied-water rate

  4. Variante de Dandy Walker: relato de caso = Dandy Walker variant: a case report

    Directory of Open Access Journals (Sweden)

    Khan, Richard Lester

    2009-01-01

    Conclusões: este artigo procura caracterizar a variante de Dandy Walker, que é uma malformação congênita do sistema nervoso central e é o tipo mais comum da Síndrome de Dandy Walker. Seu fenótipo é variável, devendo-se sempre pesquisar malformações tanto intra quanto extracranianas, visto que o risco de mortalidade pós-natal aumenta quando existe esta associação. O tratamento envolve equipe multidisciplinar e o prognóstico é reservado, variando conforme o fenótipo

  5. Biomimetic Molecular Signaling using DNA Walkers on Microparticles.

    Science.gov (United States)

    Damase, Tulsi Ram; Spencer, Adam; Samuel, Bamidele; Allen, Peter B

    2017-06-22

    We report the release of catalytic DNA walkers from hydrogel microparticles and the detection of those walkers by substrate-coated microparticles. This might be considered a synthetic biology analog of molecular signal release and reception. One type of particles was coated with components of a DNA one-step strand displacement (OSD) reaction to release the walker. A second type of particle was coated with substrate (or "track") for the molecular walker. We distinguish these particle types using fluorescence barcoding: we synthesized and distinguished multiple particle types with multicolor fluorescence microscopy and automated image analysis software. This represents a step toward amplified, multiplex, and microscopically localized detection based on DNA nanotechnology.

  6. Random walk on a population of random walkers

    International Nuclear Information System (INIS)

    Agliari, E; Burioni, R; Cassi, D; Neri, F M

    2008-01-01

    We consider a population of N labelled random walkers moving on a substrate, and an excitation jumping among the walkers upon contact. The label X(t) of the walker carrying the excitation at time t can be viewed as a stochastic process, where the transition probabilities are a stochastic process themselves. Upon mapping onto two simpler processes, the quantities characterizing X(t) can be calculated in the limit of long times and low walkers density. The results are compared with numerical simulations. Several different topologies for the substrate underlying diffusion are considered

  7. Realization of Robertson-Walker spacetimes as affine hypersurfaces

    International Nuclear Information System (INIS)

    Chen Bangyen

    2007-01-01

    Due to the growing interest in embeddings of spacetimes in higher dimensional spaces, we consider a special type of embedding. We prove that Robertson-Walker spacetimes can be embedded as centroaffine hypersurfaces and graph hypersurfaces in some affine spaces in such a way that the induced relative metrics are exactly the Lorentzian metrics on the Robertson-Walker spacetimes. Such realizations allow us to view Robertson-Walker spacetimes and their submanifolds as affine submanifolds in a natural way. Consequently, our realizations make it possible to apply the tools of affine differential geometry to study Robertson-Walker spacetimes and their submanifolds

  8. Effects of citrus and avocado irrigation and nitrogen-form soil amendment on host selection by adult Homalodisca vitripennis (Hemiptera: Cicadellidae).

    Science.gov (United States)

    Nadel, H; Seligmann, R; Johnson, M W; Hagler, J R; Stenger, D C; Groves, R L

    2008-06-01

    Host plant water status is thought to influence dispersal of the xylophagous leafhopper Homalodisca vitripennis Germar, especially where plants are grown under high evaporative demand. Preference by adult H. vitripennis for plants grown under different water deficit and nitrogen form fertilization regimens was studied under laboratory conditions. Leafhopper abundance and ovipositional preference were studied on potted 'Washington navel' orange and 'Haas' avocado in cage choice tests, and feeding rate was estimated using excreta produced by insects confined on plants. A similar study compared responses to citrus treated with 1:1 and 26:1 ratios of fertigated nitrate-N to ammonium-N. The insects were more abundant, oviposited, and fed significantly more on surplus-irrigated plants than on plants under moderate continuous deficit irrigation except avocado feeding, which was nearly significant. Plants exposed to drought became less preferred after 3 and 7 d in avocado and citrus, respectively. Citrus xylem fluid tension at this point was estimated at 0.93 MPa. A corresponding pattern of decline in feeding rate was observed on citrus, but on avocado, feeding rate was low overall and not statistically different between treatments. No statistical differences in abundance, oviposition, or feeding were detected on citrus fertigated with 26:1 or 1:1 ratios of nitrate-N to ammonium-N. Feeding occurred diurnally on both plant species. Discussion is provided on the potential deployment of regulated deficit irrigation to manage H. vitripennis movement as part of a multitactic effort to minimize the risk of disease outbreaks from Xylella fastidiosa Wells et al. in southern California agriculture.

  9. Feeding and development of the glassy-winged sharpshooter, Homalodisca vitripennis, on Australian native plant species and implications for Australian biosecurity.

    Directory of Open Access Journals (Sweden)

    Anna A Rathé

    Full Text Available In any insect invasion the presence or absence of suitable food and oviposition hosts in the invaded range is a key factor determining establishment success. The glassy-winged sharpshooter, Homalodisca vitripennis, is an important insect vector of the xylem-limited bacterial plant pathogen, Xylella fastidiosa, which causes disease in numerous host plants including food and feedstock crops, ornamentals and weeds. Both the pathogen and the vector are native to the Americas and are considered to be highly invasive. Neither has been detected in Australia. Twelve Australian native plant species present in the USA were observed over two years for suitability as H. vitripennis feeding, oviposition and nymph development hosts. Hosts providing evidence of adult or nymph presence were Leptospermum laevigatum, Acacia cowleana, Eremophila divaricata, Eucalyptus wandoo, Hakea laurina, Melaleuca laterita and Swainsona galegifolia. An oviposition-suitability field study was conducted with citrus, a favoured oviposition host, as a positive control. Citrus and L. laevigatum, A. cowleana, B. ericifolia×B. spinulosa, C. pulchella, E. divaricata, E. wandoo, H. laurina, and S. galegifolia were found to be oviposition hosts. Egg parasitism by the mymarid parasitoid Gonatocerus ashmeadi was observed on all Australian plants. A number of Australian plants that may facilitate H. vitripennis invasion have been identified and categorised as 'high risk' due to their ability to support all three life stages (egg, nymph and adult of the insect in the field (L. laevigatum, A. cowleana, E. divaricata, H. laurina, and S. galegifolia. The implications of these host status and natural enemy research findings are discussed and placed in an Australian invasion context.

  10. Why is walker-assisted gait metabolically expensive?

    Science.gov (United States)

    Priebe, Jonathon R; Kram, Rodger

    2011-06-01

    Walker-assisted gait is reported to be ∼200% more metabolically expensive than normal bipedal walking. However, previous studies compared different walking speeds. Here, we compared the metabolic power consumption and basic stride temporal-spatial parameters for 10 young, healthy adults walking without assistance and using 2-wheeled (2W), 4-wheeled (4W) and 4-footed (4F) walker devices, all at the same speed, 0.30m/s. We also measured the metabolic power demand for walking without any assistive device using a step-to gait at 0.30m/s, walking normally at 1.25m/s, and for repeated lifting of the 4F walker mimicking the lifting pattern used during 4F walker-assisted gait. Similar to previous studies, we found that the cost per distance walked was 217% greater with a 4F walker at 0.30m/s compared to unassisted, bipedal walking at 1.25m/s. Compared at the same speed, 0.30m/s, using a 4F walker was still 82%, 74%, and 55% energetically more expensive than walking unassisted, with a 4W walker and a 2W walker respectively. The sum of the metabolic cost of step-to walking plus the cost of lifting itself was equivalent to the cost of walking with a 4F walker. Thus, we deduce that the high cost of 4F walker assisted gait is due to three factors: the slow walking speed, the step-to gait pattern and the repeated lifting of the walker. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Seasonal population dynamics of Homalodisca vitripennis (Hemiptera: Cicadellidae) in sweet orange trees maintained under continuous deficit irrigation.

    Science.gov (United States)

    Krugner, Rodrigo; Groves, Russell L; Johnson, Marshall W; Flores, Arnel P; Hagler, James R; Morse, Joseph G

    2009-06-01

    A 2-yr study was conducted in a citrus orchard (Citrus sinensis L. Osbeck cultivar Valencia) to determine the influence of plant water stress on the population dynamics of glassy-winged sharpshooter, Homalodisca vitripennis (Germar). Experimental treatments included irrigation at 100% of the crop evapotranspiration rate (ET(c)) and continuous deficit-irrigation regimens at 80 and 60% ET(c). Microclimate and plant conditions monitored included temperature and humidity in the tree canopy, leaf surface temperature, water potential, and fruit quality and yield. Glassy-winged sharpshooter population densities and activity were monitored weekly by a combination of visual inspections, beat net sampling, and trapping. Glassy-winged sharpshooter populations were negatively affected by severe plant water stress; however, population densities were not linearly related to decreasing water availability in plants. Citrus trees irrigated at 60% ET(c) had significantly warmer leaves, lower xylem water potential, and consequently hosted fewer glassy-winged sharpshooter eggs, nymphs, and adults than trees irrigated at 80% ET(c). Citrus trees irrigated at 100% ET(c) hosted similar numbers of glassy-winged sharpshooter stages as trees irrigated at 60% ET(c) and a lower number of glassy-winged sharpshooter nymphs than the 80% ET(c) treatment, specifically during the nymphal density peak in mid-April to early July. Irrigation treatments did not affect populations of monitored natural enemies. Although the adult glassy-winged sharpshooter population was reduced, on average, by 50% in trees under severe water stress, the total number of fruit and number of fruit across several fruit grade categories were significantly lower in the 60% ET(c) than in the 80 and 100% ET(c) irrigation treatments.

  12. Helen M. Walker: Influential in 1929 and Still Cited Today.

    Science.gov (United States)

    Rice, Marti H.; Stallings, William M.

    Helen M. Walker contributed to the field of educational research and statistics during a 55-year career. Born in Iowa in 1891, Walker earned a bachelor's degree from Iowa Wesleyan College and taught high school mathematics for nine years. She then taught at the University of Kansas while doing graduate work. One source noted that she was the first…

  13. Hydrogel Walkers with Electro-Driven Motility for Cargo Transport.

    Science.gov (United States)

    Yang, Chao; Wang, Wei; Yao, Chen; Xie, Rui; Ju, Xiao-Jie; Liu, Zhuang; Chu, Liang-Yin

    2015-08-28

    In this study, soft hydrogel walkers with electro-driven motility for cargo transport have been developed via a facile mould-assisted strategy. The hydrogel walkers consisting of polyanionic poly(2-acrylamido-2-methylpropanesulfonic acid-co-acrylamide) exhibit an arc looper-like shape with two "legs" for walking. The hydrogel walkers can reversibly bend and stretch via repeated "on/off" electro-triggers in electrolyte solution. Based on such bending/stretching behaviors, the hydrogel walkers can move their two "legs" to achieve one-directional walking motion on a rough surface via repeated "on/off" electro-triggering cycles. Moreover, the hydrogel walkers loaded with very heavy cargo also exhibit excellent walking motion for cargo transport. Such hydrogel systems create new opportunities for developing electro-controlled soft systems with simple design/fabrication strategies in the soft robotic field for remote manipulation and transportation.

  14. A review of the functionalities of smart walkers.

    Science.gov (United States)

    Martins, Maria; Santos, Cristina; Frizera, Anselmo; Ceres, Ramón

    2015-10-01

    There is a need to conceptualize and improve the investigation and developments in assistive devices, focusing on the design and effectiveness of walkers in the user's rehabilitation process and functional compensation. This review surveys the importance of smart walkers in maintaining mobility and discusses their potential in rehabilitation and their demands as assistive devices. It also presents related research in addressing and quantifying the smart walker's efficiency and influence on gait. Besides, it discusses smart walkers focusing on studies related to the concept of autonomous and shared-control and manual guidance, the use of smart walkers as personal helpers to sit-to-stand and diagnostic tools for patients' rehabilitation through the evaluation of their gait. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  15. Dandy-Walker variant in Coffin-Siris syndrome.

    Science.gov (United States)

    Imai, T; Hattori, H; Miyazaki, M; Higuchi, Y; Adachi, S; Nakahata, T

    2001-04-22

    We describe a five-month-old male infant with Coffin-Siris syndrome, the so-called Dandy-Walker variant (hypoplasia of the cerebellar vermis with cystic dilatation of the fourth ventricle, but without enlargement of the posterior fossa), and partial agenesis of the corpus callosum. Dandy-Walker malformation and mega cisterna magna, but not Dandy-Walker variant, have been reported in Coffin-Siris syndrome. The presence of Dandy-Walker variant in the infant we described confirms that the full continuum of the Dandy-Walker complex can occur in Coffin-Siris syndrome. The yet unidentified gene(s) for the syndrome may be related to the development of the hindbrain. Copyright 2001 Wiley-Liss, Inc.

  16. Hymenoptera stings in Brazil: a neglected health threat in Amazonas State

    OpenAIRE

    Costa, Allyson Guimarães; Chaves, Bárbara Aparecida; Murta, Felipe Leão Gomes; Sachett, Jacqueline Almeida Gonçalves; Sampaio, Vanderson Souza; Silva, Vanessa Costa; Monteiro, Wuelton Marcelo

    2018-01-01

    Abstract INTRODUCTION: Hymenoptera injuries are commonly caused by stinging insects. In Amazonas state, Brazil, there is no information regarding distribution, profile, and systemic manifestations associated with Hymenoptera injuries. METHODS: This study aimed to identify risk factors for systemic manifestation using the Brazilian Notifiable Diseases Surveillance System (2007 to 2015). RESULTS: Half of Hymenoptera injuries were caused by bee stings. Hymenoptera injuries were concentrate...

  17. Tachyons in Robertson-Walker Cosmology

    CERN Document Server

    Tomaschitz, R

    1998-01-01

    Superluminal signal transfer is studied in the context of a preferred cosmic frame of reference provided by the galactic background. The receding galaxies constitute a frame of absolute rest, in which the energy of tachyons (faster-than-light particles) is unambiguously defined as a positive quantity. The causality violation which arises in relativistic tachyonic theories is avoided. We define interactions of particles and tachyons in terms of elastic head-on collisions and energy-momentum conservation. To compare the theory developed with existing relativistic theories, tachyons are studied at first in a Minkowski universe, and the causality of a superluminal communication process is analyzed. Then we discuss the dynamics of tachyons in a Robertson-Walker universe with linear expansion factor and negatively curved three-space. We point out the consequences that the space expansion has on tachyons, like a finite life-time in the frame of absolute rest, and multiple images in the rest frames of moving observer...

  18. Dissipative Boltzmann-Robertson-Walker cosmologies

    International Nuclear Information System (INIS)

    Hiscock, W.A.; Salmonson, J.

    1991-01-01

    The equations governing a flat Robertson-Walker cosmological model containing a dissipative Boltzmann gas are integrated numerically. The bulk viscous stress is modeled using the Eckart and Israel-Stewart theories of dissipative relativistic fluids; the resulting cosmologies are compared and contrasted. The Eckart models are shown to always differ in a significant quantitative way from the Israel-Stewart models. It thus appears inappropriate to use the pathological (nonhyperbolic) Eckart theory for cosmological applications. For large bulk viscosities, both cosmological models approach asymptotic nonequilibrium states; in the Eckart model the total pressure is negative, while in the Israel-Stewart model the total pressure is asymptotically zero. The Eckart model also expands more rapidly than the Israel-Stewart models. These results suggest that ''bulk-viscous'' inflation may be an artifact of using a pathological fluid theory such as the Eckart theory

  19. Aging in mortal superdiffusive Lévy walkers

    Science.gov (United States)

    Stage, Helena

    2017-12-01

    A growing body of literature examines the effects of superdiffusive subballistic movement premeasurement (aging or time lag) on observations arising from single-particle tracking. A neglected aspect is the finite lifetime of these Lévy walkers, be they proteins, cells, or larger structures. We examine the effects of aging on the motility of mortal walkers, and discuss the means by which permanent stopping of walkers may be categorized as arising from "natural" death or experimental artifacts such as low photostability or radiation damage. This is done by comparison of the walkers' mean squared displacement (MSD) with the front velocity of propagation of a group of walkers, which is found to be invariant under time lags. For any running time distribution of a mortal random walker, the MSD is tempered by the stopping rate θ . This provides a physical interpretation for truncated heavy-tailed diffusion processes and serves as a tool by which to better classify the underlying running time distributions of random walkers. Tempering of aged MSDs raises the issue of misinterpreting superdiffusive motion which appears Brownian or subdiffusive over certain time scales.

  20. Aging in mortal superdiffusive Lévy walkers.

    Science.gov (United States)

    Stage, Helena

    2017-12-01

    A growing body of literature examines the effects of superdiffusive subballistic movement premeasurement (aging or time lag) on observations arising from single-particle tracking. A neglected aspect is the finite lifetime of these Lévy walkers, be they proteins, cells, or larger structures. We examine the effects of aging on the motility of mortal walkers, and discuss the means by which permanent stopping of walkers may be categorized as arising from "natural" death or experimental artifacts such as low photostability or radiation damage. This is done by comparison of the walkers' mean squared displacement (MSD) with the front velocity of propagation of a group of walkers, which is found to be invariant under time lags. For any running time distribution of a mortal random walker, the MSD is tempered by the stopping rate θ. This provides a physical interpretation for truncated heavy-tailed diffusion processes and serves as a tool by which to better classify the underlying running time distributions of random walkers. Tempering of aged MSDs raises the issue of misinterpreting superdiffusive motion which appears Brownian or subdiffusive over certain time scales.

  1. Pediatricians' attitude about the use of infant walkers.

    Science.gov (United States)

    Kara, Semra; Yilmaz, Ayşe Esra; Gümüş Dogan, Derya; Bilici, Meki; Turkay, Sadi; Akca, Halise; Catal, Ferhat

    2013-12-01

    Infant walkers are still very popular even though their use might cause injuries. A survey was carried out to obtain information about attitudes and pediatricians' approach regarding the use of infant walkers. Two hundred and forty seven pediatricians who attended the 44th Turkish Congress of Pediatrics and Europediatrics (2008) were invited to reply to a questionnaire prepared by the authors. Two hundred and twenty six questionnaires replied in full were included. The median age of participants (119 women) was 39 years old (range: 29-58 years old). Out of the total, 4% recommended the use of a walker; 32.2% left the decision to parents' judgment, and 63.7% did not recommend its use. A hundred and five had previously treated an infant who had an injury associated to the use of the walker; out of them, 73.3% did not recommend its use and 57.1% stated that there should be a ban on the sale and manufacture of walkers. Out of the total number of surveyed pediatricians, 4% recommend the use of infant walkers and over 30% leave this decision to parents. Those pediatricians who took care of babies who had an injury associated to the use of a walker were less prone to recommending it.

  2. Intelligent control of a smart walker and its performance evaluation.

    Science.gov (United States)

    Grondin, Simon L; Li, Qingguo

    2013-06-01

    Recent technological advances have allowed the development of force-dependent, intelligently controlled smart walkers that are able to provide users with enhanced mobility, support and gait assistance. The purpose of this study was to develop an intelligent rule-based controller for a smart walker to achieve a smooth interaction between the user and the walker. This study developed a rule-based mapping between the interaction force, measured by a load cell attached to the walker handle, and the acceleration of the walker. Ten young, healthy subjects were used to evaluate the performance of the proposed controller compared to a well-known admittance-based control system. There were no significant differences between the two control systems concerning their user experience, velocity profiles or average cost of transportation. However, the admittance-based control system required a 1.2N lower average interaction force to maintain the 1m/s target speed (p = 0.002). Metabolic data also indicated that smart walker-assisted gait could considerably reduce the metabolic demand of walking with a four-legged walker.

  3. Perceiving Direction of a Walker: Effect of Body Appearance

    Directory of Open Access Journals (Sweden)

    Kazuya Ono

    2011-05-01

    Full Text Available Human can perceive others' walking direction accurately even with 117ms observation (Sato, et al., ECVP2008. We aimed to see whether appearance of walker's body affects the accuracy of perceiving direction of the walker. Thus, we employed three different appearances: realistic human computer-graphics body (CG-human, nonrealistic cylinder-assembled body (Cylinders, and point-light walker (Points. We made a three-dimensional model of an adult-size walker who walked at a place. CG-human stimuli were generated by rendering the model with smooth shading. We made Cylinders stimuli by replacing body parts such as arms, legs, head, and hands with cylinders. Points stimuli were made by tracking 18 positions (mostly joints of the body like biological motion. One of walkers was presented for 117, 250, 500 or 1000ms while its direction was randomly varied by 3deg steps to 21deg left or right. Observers judged whether the walker was walking toward them (hit or not (miss, and self-range was measured in terms of the standard deviation for hit distributions. The perceived self-range was narrowed with long duration, and with CG-human stimulus. It is suggested that the accuracy of perceiving walker's direction depends on body appearance, and it is higher for human-like body than nonhuman body.

  4. Hymenoptera Stings and the Acute Kidney Injury

    Directory of Open Access Journals (Sweden)

    Yashad Dongol

    2013-07-01

    Full Text Available Hymenoptera stings are a health concern. Apidae (bees, Vespidae (hornets, yellow jackets and wasps and Formicidae (ants are medically-important stinging insects under the order Hymenoptera. Clinical features from simple skin manifestations to severe and fatal organ injury are due to the hypersensitivity reactions and/ or the toxic effects of the venom inoculated. Here we discuss on Hymenoptera stings involving apids (honey bees and vespids (wasps, hornets and yellow jackets and their effect on renal function and associated morphological changes in the kidney. Despite the differences in venom composition and quantity released per sting in two insect groups, both lead to similar medical consequences, such as localised normal allergic reactions, mild to severe anaphylaxis and shock and multiple organ and tissue injury leading to multiple organ failure. Acute kidney injury (AKI is one of the unusual complications of Hymenoptera stings and has the basis of both immune-mediated and toxic effects. Evidence has proven that supportive therapy along with the standard medication is very efficient in completely restoring the kidney function without any recurrence.

  5. HYMENOPTERA ALLERGENS: FROM VENOM TO VENOME

    Directory of Open Access Journals (Sweden)

    Edzard eSpillner

    2014-02-01

    Full Text Available In Western Europe hymenoptera venom allergy primarily relates to venoms of the honeybee and the common yellow jacket. In contrast to other allergen sources, only a few major components of hymenoptera venoms had been characterized until recently. Improved expression systems and proteomic detection strategies have allowed the identification and characterization of a wide range of additional allergens. The field of hymenoptera venom allergy research has moved rapidly from focusing on venom extract and single major allergens to a molecular understanding of the entire venome as a system of unique and characteristic components. An increasing number of such components has been identified, characterized regarding function and assessed for allergenic potential. Moreover, advanced expression strategies for recombinant production of venom allergens allow selective modification of molecules and provide insight into different types of IgE reactivities and sensitization patterns. The obtained information contributes to an increased diagnostic precision in hymenoptera venom allergy and may serve for monitoring, reevaluation and improvement of current therapeutic strategies.

  6. De wespbijen (Nomada) van Nederland (Hymenoptera: Apidae)

    NARCIS (Netherlands)

    Smit, J.

    2004-01-01

    The wasp bees (Nomada) of the Netherlands (Hymenoptera: Apidae) In the Netherlands 44 species of Nomada are known to occur. The name wasp bee is derived from the often yellow and black colour, which give the insects a wasplike appearance. Nomada bees are cleptoparasites mostly with Andrena species.

  7. Basophil-activation tests in hymenoptera allergy

    NARCIS (Netherlands)

    Dubois, Anthony E. J.; van der Heide, Sicco

    The measurement of basophil-activation markers may be useful in detecting IgIE-mediated sensitization but the relevance for application of the basophil-activation test in prediction of clinical reactivity in Hymenoptera allergy is very limited. For this reason, this test currently has no established

  8. Interacting walkers on the Cayley tree, and polymer statistics

    International Nuclear Information System (INIS)

    Priezzhev, V.B.

    1986-01-01

    We obtain the generating function for an ensemble of random walkers on the Cayley tree of coordination number z. The pair interaction between walkers is taken into account. This forbids two walkers to occupy the same lattice point after an equal number of steps. Interacting polymer statistics results from this model if one associates time (or the number of steps) with an additional space coordinate. The limiting free energy appears in a form that corresponds to the phase transition of ''3/2 order.''

  9. Experimental detection of domain wall propagation above the Walker field

    International Nuclear Information System (INIS)

    Kondou, Kouta; Chiba, Daichi; Kobayashi, Kensuke; Ono, Teruo; Ohshima, Norikazu; Kasai, Shinya

    2012-01-01

    The domain wall (DW) velocity above the Walker field drops abruptly with increasing magnetic field, because of the so-called Walker breakdown, where the DW moves with a precessional mode. On applying the higher field, the DW velocity again starts to increase gradually. We report the DW propagation around this local minimum regime in detail, investigated through the time-resolved electrical detection technique, with a magnetic tunnel junction. Just above the Walker field, we succeeded in detecting the precessional motion of the DW in a real-time regime, while a different mode appeared around the local minimum of the DW velocity. (paper)

  10. Human-robot interaction strategies for walker-assisted locomotion

    CERN Document Server

    Cifuentes, Carlos A

    2016-01-01

    This book presents the development of a new multimodal human-robot interface for testing and validating control strategies applied to robotic walkers for assisting human mobility and gait rehabilitation. The aim is to achieve a closer interaction between the robotic device and the individual, empowering the rehabilitation potential of such devices in clinical applications. A new multimodal human-robot interface for testing and validating control strategies applied to robotic walkers for assisting human mobility and gait rehabilitation is presented. Trends and opportunities for future advances in the field of assistive locomotion via the development of hybrid solutions based on the combination of smart walkers and biomechatronic exoskeletons are also discussed. .

  11. Phytoreovirus-like sequences isolated from salivary glands of the glassy-winged sharpshooter Homolodisca vitripennis (Hemiptera: Cicadellidae)

    International Nuclear Information System (INIS)

    Katsar, C.S.; Hunter, W.B.; Sinisterra, X.H.

    2007-01-01

    The salivary glands of the Glassy-winged sharpshooter (GWSS), Homalodisca vitripennis Germar 1821, (syn. H. coagulata, Hemiptera: Cicadellidae) were collected and used to produce a cDNA library. Examination by BLASTX analyses identified 2 viral sequences, one a 610-base pair fragment and a second 839-base pair fragment, both of which had significant homology to viruses within the genus Phytoreovirus. Resequencing of the fragments confirmed sequence validities. These sequences were used for in silico protein translation and BLASTP analysis confirming the established homology. While the GWSS is the primary vector of Pierce's disease of grapes, this is the first report that GWSS may be a vector of a phytoreoviruses. Phylogenetic and homology comparisons with BLASTX, BLASTP, and PAUP analyses indicated that the viral sequences isolated from GWSS were closely related to the viruses in the Family Reoviridae, Genus Phytoreovirus, specifically Rice Dwarf Phytoreovirus (RDV). RDV is the only plant reovirus that is not limited to the phloem. Phytoreoviruses are transmitted in a propagative manner by cicadellid leafhoppers (Hemiptera: Cicadellidae), which acquire and transmit them during feeding. Phytoreoviruses have been reported from Agallian, Agalliopsis, Nephotettix, and Recilia, genera of leafhoppers, with evidence for transovarial transmission. The GWSS, although considered to feed primarily from the xylem, ingests from other plant tissues, such as the phloem and mesophyll during probing similar to other leafhoppers. The feeding behavior and wide host range of the GWSS provides an overlapping condition for these two organisms, leafhopper and virus. GWSS will feed from grasses as a transitory host, and on herbaceous and woody plants as primary hosts, which may favor the acquisition and transmission of Phytoreovirus by this leafhopper. Monitoring for an increase of Phytoreovirus spread in graminaceous crops that are in proximity to vineyards or tree crop orchards, where

  12. Aspectos bionômicos de Eois tegularia (Guenée e Eois glauculata (Walker (Lepidoptera, Geometridae, Larentiinae e seus parasitóides Bionomic aspects of Eois tegularia (Guenée and Eois glauculata (Walker (Lepidoptera, Geometridae, Larentiinae and their parasitoids

    Directory of Open Access Journals (Sweden)

    Sandra Maria Pasenow Braga

    2001-09-01

    Full Text Available Eois tegularia (Guenée, [1858] and Eois glauculata (Walker, [1863] larvae were studied by one year in semidec iduous forest at Canchim Farm (EMBRAPA, São Carlos, São Paulo, Brazil. Specimens were hosted by species of Piper Linnaeus (Piperaceae: P. mollicomum Kunth, P. amalogo Linnaeus, P. glabratum Kunth and P. gaudichaudianum Kunth. Some parasitoids were reared from the larvae of Eois Hübner, 1818 species, as follow. Hymenoptera: Cotesia Cameron, 1891, Apanteles Foerster, 1862, Glyptapanteles Ashmead, 1904, Dolichogenidea Viereck, 1911, Meteorus Haliday, 1835 (Braconidae; Mesochorus Gravenhorst, 1829, Venturia Schrottky, 1902 (Ichneumonidae; Elachertus Spinola, 1811 (Eulophidae; Perilampus Latreille, 1809 (Perilampidae, Diptera: Myiopharus Brauer & Bergenstamm, 1889 (Tachinidae.

  13. Walker Branch Watershed Vegetation Inventory, 1967-1997

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: The original objectives of the long-term vegetation survey of Walker Branch Watershed in eastern Tennessee (WBW; Curlin and Nelson 1968) was to quantify...

  14. Interaction of two walkers: wave-mediated energy and force.

    Science.gov (United States)

    Borghesi, Christian; Moukhtar, Julien; Labousse, Matthieu; Eddi, Antonin; Fort, Emmanuel; Couder, Yves

    2014-12-01

    A bouncing droplet, self-propelled by its interaction with the waves it generates, forms a classical wave-particle association called a "walker." Previous works have demonstrated that the dynamics of a single walker is driven by its global surface wave field that retains information on its past trajectory. Here we investigate the energy stored in this wave field for two coupled walkers and how it conveys an interaction between them. For this purpose, we characterize experimentally the "promenade modes" where two walkers are bound and propagate together. Their possible binding distances take discrete values, and the velocity of the pair depends on their mutual binding. The mean parallel motion can be either rectilinear or oscillating. The experimental results are recovered analytically with a simple theoretical framework. A relation between the kinetic energy of the droplets and the total energy of the standing waves is established.

  15. Mechanical efficiency of a champion walker | Wyndham | South ...

    African Journals Online (AJOL)

    Oxygen consumptions were measured on a champion walker, while walking at between 6·4 and 16·9 km / hand while running at between 11.3 and 17.7 km/h. Above 9.7 km /h the curve of oxygen consumption against speed for walking was almost twice as steep as that for running, indicating that even champion walkers are ...

  16. Single locus complementary sex determination in Hymenoptera : an "unintelligent" design?

    NARCIS (Netherlands)

    Wilgenburg, Ellen van; Driessen, Gerard; Beukeboom, Leo W.

    2006-01-01

    The haplodiploid sex determining mechanism in Hymenoptera (males are haploid, females are diploid) has played an important role in the evolution of this insect order. In Hymenoptera sex is usually determined by a single locus, heterozygotes are female and hemizygotes are male. Under inbreeding,

  17. Single locus complementary sex determination in Hymenoptera: an "unintelligent" design?

    NARCIS (Netherlands)

    van Wilgenburg, E.; Driessen, G.J.J.; Beukeboom, L.W.

    2006-01-01

    The haplodiploid sex determining mechanism in Hymenoptera (males are haploid, females are diploid) has played an important role in the evolution of this insect order. In Hymenoptera sex is usually determined by a single locus, heterozygotes are female and hemizygotes are male. Under inbreeding,

  18. ACADEMIC TRAINING (R.P. Walker)

    CERN Multimedia

    Françoise Benz

    2002-01-01

    15, 16, 17 May LECTURE SERIES from 11.00 to 12.00 hrs - Council room, bldg. 503 on 15 May, Auditorium, bldg. 500 on 16 and 17 May Introduction to free electron lasers by R.P. Walker / Rutherford Laboratory, UK The Free-electron laser (FEL) is a source of coherent electromagnetic radiation based on a relativistic electron beam. First operated 25 years ago, the FEL has now reached a stage of maturity for operation in the infra-red region of the spectrum and several facilities provide intense FEL radiation beams for research covering a wide range of disciplines. Several projects both underway and proposed aim at pushing the minimum wavelength from its present limit around 100 nm progressively down to the 1 Angstrom region where the X-ray FEL would open up many new and exciting research possibilities. Other developments aim at increasing power levels to the 10's of kW level. In this series of lectures we give an introduction to the basic principles of FELs and their different modes of operation, and summarise the...

  19. Neurodevelopment in preschool idiopathic toe-walkers.

    Science.gov (United States)

    Martín-Casas, P; Ballestero-Pérez, R; Meneses-Monroy, A; Beneit-Montesinos, J V; Atín-Arratibel, M A; Portellano-Pérez, J A

    2017-09-01

    Idiopathic toe walking, a differential diagnosis for neurological and orthopaedic disorders, has been associated with neurodevelopmental alterations. Neurodevelopmental assessment at early ages using specific tests may improve management and follow-up of these patients. The aim of our study is to analyse the neurodevelopmental characteristics of preschool idiopathic toe-walkers (ITW) by comparing them to a control group. Our descriptive cross-sectional study compared possible risk factors, neurodevelopmental characteristics, and scores on the Child Neuropsychological Maturity Questionnaire (CUMANIN) between a group of 56 ITWs aged 3 to 6 and a control group including 40 children. The proportion of males was significantly higher in the ITW group (P=.008). The percentage of patients with a family history (P=.000) and biological risk factors during the perinatal period (P=.032) was also higher in this group. According to the parents' reports, motor coordination in ITWs was significantly poorer (59%; P=.009). ITWs scored significantly lower on CUMANIN subscales of psychomotricity (=0,001) and memory (P=.001), as well as in verbal development (P=.000), non-verbal development (P=.026), and overall development (P=.004). Foot preference was less marked in the ITW group (P=.047). The neurodevelopmental characteristics of our sample suggest that idiopathic toe walking is a marker of neurodevelopmental impairment. However, further studies are necessary to confirm these findings. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Lonomia obliqua Walker (Lepidoptera: Saturniidae: hemostasis implications

    Directory of Open Access Journals (Sweden)

    Silviane Maggi

    2015-06-01

    Full Text Available Summary In southern Brazil, since 1989, several cases of accidents produced by unwilling contact with the body of poisonous caterpillars of the moth species Lonomia obliqua Walker, 1855 (Lepidoptera: Saturniidae, were described. L. obliqua caterpillars have gregarious behavior and feed on leaves of host trees during the night, staying grouped in the trunk during the day, which favors the occurrence of accidents with the species. This caterpillar has the body covered with bristles that on contact with the skin of individuals, breaks and release their contents, inoculating the venom into the victim. The basic constitution of the venom is protein and its components produce physiological changes in the victim, which include disturbances in hemostasis. Hemorrhagic syndrome associated with consumption coagulopathy, intravascular hemolysis and acute renal failure are some of the possible clinical manifestations related to poisoning by L. obliqua. Specific laboratory tests for diagnosis of poisoning have not been described previously. The diagnosis of poisoning is made based on the patient's medical history, clinical manifestations, erythrocyte levels, and, primarily, parameters that evaluate blood coagulation. Treatment is performed with the use of supportive care and the administration of specific hyperimmune antivenom. Poisoning can be serious and even fatal.

  1. Component Resolved Diagnosis in Hymenoptera Anaphylaxis.

    Science.gov (United States)

    Tomsitz, D; Brockow, K

    2017-06-01

    Hymenoptera anaphylaxis is one of the leading causes of severe allergic reactions and can be fatal. Venom-specific immunotherapy (VIT) can prevent a life-threatening reaction; however, confirmation of an allergy to a Hymenoptera venom is a prerequisite before starting such a treatment. Component resolved diagnostics (CRD) have helped to better identify the responsible allergen. Many new insect venom allergens have been identified within the last few years. Commercially available recombinant allergens offer new diagnostic tools for detecting sensitivity to insect venoms. Additional added sensitivity to nearly 95% was introduced by spiking yellow jacket venom (YJV) extract with Ves v 5. The further value of CRD for sensitivity in YJV and honey bee venom (HBV) allergy is more controversially discussed. Recombinant allergens devoid of cross-reactive carbohydrate determinants often help to identify the culprit venom in patients with double sensitivity to YJV and HBV. CRD identified a group of patients with predominant Api m 10 sensitization, which may be less well protected by VIT, as some treatment extracts are lacking this allergen. The diagnostic gap of previously undetected Hymenoptera allergy has been decreased via production of recombinant allergens. Knowledge of analogies in interspecies proteins and cross-reactive carbohydrate determinants is necessary to distinguish relevant from irrelevant sensitizations.

  2. Hymenoptera venom review focusing on Apis mellifera

    Directory of Open Access Journals (Sweden)

    P. R. de Lima

    2003-01-01

    Full Text Available Hymenoptera venoms are complex mixtures containing simple organic molecules, proteins, peptides, and other bioactive elements. Several of these components have been isolated and characterized, and their primary structures determined by biochemical techniques. These compounds are responsible for many toxic or allergic reactions in different organisms, such as local pain, inflammation, itching, irritation, and moderate or severe allergic reactions. The most extensively characterized Hymenoptera venoms are bee venoms, mainly from the Apis genus and also from social wasps and ant species. However, there is little information about other Hymenoptera groups. The Apis venom presents high molecular weight molecules - enzymes with a molecular weight higher than 10.0 kDa - and peptides. The best studied enzymes are phospholipase A2, responsible for cleaving the membrane phospholipids, hyaluronidase, which degrades the matrix component hyaluronic acid into non-viscous segments and acid phosphatase acting on organic phosphates. The main peptide compounds of bee venom are lytic peptide melittin, apamin (neurotoxic, and mastocyte degranulating peptide (MCD.

  3. Diversity of peptidic and proteinaceous toxins from social Hymenoptera venoms.

    Science.gov (United States)

    Dos Santos-Pinto, José Roberto Aparecido; Perez-Riverol, Amilcar; Lasa, Alexis Musacchio; Palma, Mario Sergio

    2018-06-15

    Among venomous animals, Hymenoptera have been suggested as a rich source of natural toxins. Due to their broad ecological diversity, venom from Hymenoptera insects (bees, wasps and ants) have evolved differentially thus widening the types and biological functions of their components. To date, insect toxinology analysis have scarcely uncovered the complex composition of bee, wasp and ant venoms which include low molecular weight compounds, highly abundant peptides and proteins, including several allergens. In Hymenoptera, these complex mixtures of toxins represent a potent arsenal of biological weapons that are used for self-defense, to repel intruders and to capture prey. Consequently, Hymenoptera venom components have a broad range of pharmacological targets and have been extensively studied, as promising sources of new drugs and biopesticides. In addition, the identification and molecular characterization of Hymenoptera venom allergens have allowed for the rational design of component-resolved diagnosis of allergy, finally improving the outcome of venom immunotherapy (VIT). Until recently, a limited number of Hymenoptera venoms had been unveiled due to the technical limitations of the approaches used to date. Nevertheless, the application of novel techniques with high dynamic range has significantly increased the number of identified peptidic and proteinaceous toxins. Considering this, the present review summarizes the current knowledge about the most representative Hymenoptera venom peptides and proteins which are under study for a better understanding of the insect-caused envenoming process and the development of new drugs and biopesticides. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Singular perturbations of empty Robertson-Walker cosmologies

    International Nuclear Information System (INIS)

    Newman, R.P.A.C.

    1979-02-01

    An investigation is presented which concerns a class of cosmological models defined by McVittie (1931): the universe is envisaged as a set of galaxies, idealised as point particles, which provide singular perturbations of Robertson-Walker cosmologies. The perturbations are considered only to first order in the gravitational coupling constant (8πG)/c 2 . Attention will only be given to such perturbations of empty Robertson-Walker cosmologies. Chapter 1 summarises the observational support for the type of model employed and for the smallness of the quantities to be used as perturbation coefficients. Chapter 2 provides the prerequisite analysis of Robertson-Walker cosmologies. Perturbations of empty Robertson-Walker cosmologies of non-vanishing cosmical constant are considered in general in Chapter 3. The structure of McVittie's singularly perturbed Robertson-Walker cosmologies are considered in detail in Chapter 4. The remaining chapters seek to investigate them further by way of their optical properties. Chapter 5 provides the necessary theory of geometric optics with particular regard to the intensity and distortion of a beam of light, and Chapter 6 applies this theory to the McVittie cosmologies. Chapter 7 sees the definition of an averaging procedure which leads to expressions for the intensity and distortion of a typical beam of light from a point source. (author)

  5. Ordering statistics of four random walkers on a line

    Science.gov (United States)

    Helenbrook, Brian; ben-Avraham, Daniel

    2018-05-01

    We study the ordering statistics of four random walkers on the line, obtaining a much improved estimate for the long-time decay exponent of the probability that a particle leads to time t , Plead(t ) ˜t-0.91287850 , and that a particle lags to time t (never assumes the lead), Plag(t ) ˜t-0.30763604 . Exponents of several other ordering statistics for N =4 walkers are obtained to eight-digit accuracy as well. The subtle correlations between n walkers that lag jointly, out of a field of N , are discussed: for N =3 there are no correlations and Plead(t ) ˜Plag(t) 2 . In contrast, our results rule out the possibility that Plead(t ) ˜Plag(t) 3 for N =4 , although the correlations in this borderline case are tiny.

  6. Multiple Walkers in the Wang-Landau Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G

    2005-12-28

    The mean cost for converging an estimated density of states using the Wang-Landau algorithm is measured for the Ising and Heisenberg models. The cost increases in a power-law fashion with the number of spins, with an exponent near 3 for one-dimensional models, and closer to 2.4 for two-dimensional models. The effect of multiple, simultaneous walkers on the cost is also measured. For the one-dimensional Ising model the cost can increase with the number of walkers for large systems. For both the Ising and Heisenberg models in two-dimensions, no adverse impact on the cost is observed. Thus multiple walkers is a strategy that should scale well in a parallel computing environment for many models of magnetic materials.

  7. Asymptotic shape of the region visited by an Eulerian walker.

    Science.gov (United States)

    Kapri, Rajeev; Dhar, Deepak

    2009-11-01

    We study an Eulerian walker on a square lattice, starting from an initial randomly oriented background using Monte Carlo simulations. We present evidence that, for a large number of steps N , the asymptotic shape of the set of sites visited by the walker is a perfect circle. The radius of the circle increases as N1/3, for large N , and the width of the boundary region grows as Nalpha/3, with alpha=0.40+/-0.06 . If we introduce stochasticity in the evolution rules, the mean-square displacement of the walker, approximately approximately N2nu, shows a crossover from the Eulerian (nu=1/3) to a simple random-walk (nu=1/2) behavior.

  8. Dandy walker variant and bipolar I disorder with graphomania.

    Science.gov (United States)

    Can, Serdar Suleyman; Karakaş Uğurlu, Görkem; Cakmak, Selcen

    2014-07-01

    Cerebellum is known to play an important role in coordination and motor functions. In some resent studies it is also considered to be involved in modulation of mood, cognition and psychiatric disorders. Dandy Walker Malformation is a congenital malformation that is characterized by hypoplasia or aplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle and enlargement of the posterior fossa. When the volume of posterior fossa is normal, the malformation is called Dandy Walker Variant. Case is a 32 year old male with a 12 year history of Bipolar I Disorder presented with manic and depresive symptoms, including dysphoric and depressive affect, anhedonia, suicidal thoughts and behaviours, thoughts of fear about future, overtalkativeness and graphomania, increased energy, irregular sleep, loss of appetite, increased immersion in projects, irritability, agressive behavior, impulsivity. Cranial Magnetic Resonance Imaging was compatible to the morphological features of Dandy Walker Variant.

  9. Twentieth century Walker Circulation change: data analysis and model experiments

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Qingjia [Leibniz-Institut fuer Meereswissenschaften, Kiel (Germany); Chinese Research Academy of Environmental Sciences, River and Coastal Environment Research Center, Beijing (China); Chinese Academy of Sciences, Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Qingdao (China); Latif, Mojib; Park, Wonsun; Keenlyside, Noel S.; Martin, Thomas [Leibniz-Institut fuer Meereswissenschaften, Kiel (Germany); Semenov, Vladimir A. [Leibniz-Institut fuer Meereswissenschaften, Kiel (Germany); A.M. Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences, Moscow (Russian Federation)

    2012-05-15

    Recent studies indicate a weakening of the Walker Circulation during the twentieth century. Here, we present evidence from an atmospheric general circulation model (AGCM) forced by the history of observed sea surface temperature (SST) that the Walker Circulation may have intensified rather than weakened. Observed Equatorial Indo-Pacific Sector SST since 1870 exhibited a zonally asymmetric evolution: While the eastern part of the Equatorial Pacific showed only a weak warming, or even cooling in one SST dataset, the western part and the Equatorial Indian Ocean exhibited a rather strong warming. This has resulted in an increase of the SST gradient between the Maritime Continent and the eastern part of the Equatorial Pacific, one driving force of the Walker Circulation. The ensemble experiments with the AGCM, with and without time-varying external forcing, suggest that the enhancement of the SST gradient drove an anomalous atmospheric circulation, with an enhancement of both Walker and Hadley Circulation. Anomalously strong precipitation is simulated over the Indian Ocean and anomalously weak precipitation over the western Pacific, with corresponding changes in the surface wind pattern. Some sensitivity to the forcing SST, however, is noticed. The analysis of twentieth century integrations with global climate models driven with observed radiative forcing obtained from the Coupled Model Intercomparison Project (CMIP) database support the link between the SST gradient and Walker Circulation strength. Furthermore, control integrations with the CMIP models indicate the existence of strong internal variability on centennial timescales. The results suggest that a radiatively forced signal in the Walker Circulation during the twentieth century may have been too weak to be detectable. (orig.)

  10. Casimir densities for a boundary in Robertson-Walker spacetime

    Energy Technology Data Exchange (ETDEWEB)

    Saharian, A.A., E-mail: saharian@ictp.i [Department of Physics, Yerevan State University, 1 Alex Manoogian Street, 0025 Yerevan (Armenia); Setare, M.R., E-mail: rezakord@ipm.i [Department of Science of Bijar, University of Kurdistan, Bijar (Iran, Islamic Republic of)

    2010-04-12

    For scalar and electromagnetic fields we evaluate the vacuum expectation value of the energy-momentum tensor induced by a curved boundary in the Robertson-Walker spacetime with negative spatial curvature. In order to generate the vacuum densities we use the conformal relation between the Robertson-Walker and Rindler spacetimes and the corresponding results for a plate moving by uniform proper acceleration through the Fulling-Rindler vacuum. For the general case of the scale factor the vacuum energy-momentum tensor is presented as the sum of the boundary free and boundary induced parts.

  11. Casimir densities for a boundary in Robertson-Walker spacetime

    International Nuclear Information System (INIS)

    Saharian, A.A.; Setare, M.R.

    2010-01-01

    For scalar and electromagnetic fields we evaluate the vacuum expectation value of the energy-momentum tensor induced by a curved boundary in the Robertson-Walker spacetime with negative spatial curvature. In order to generate the vacuum densities we use the conformal relation between the Robertson-Walker and Rindler spacetimes and the corresponding results for a plate moving by uniform proper acceleration through the Fulling-Rindler vacuum. For the general case of the scale factor the vacuum energy-momentum tensor is presented as the sum of the boundary free and boundary induced parts.

  12. States of low energy on Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Olbermann, Heiner

    2007-01-01

    We construct a new class of physical states of the free Klein-Gordon field in Robertson-Walker spacetimes. This is done by minimizing the expectation value of smeared stress-energy. We get an explicit expression for the state depending on the smearing function. We call it a state of low energy. States of low energy are an improvement of the concept of adiabatic vacua on Robertson-Walker spacetimes. The latter are approximations of the former. It is shown that states of low energy are Hadamard states

  13. Development of the SORRI-BAURU Posterior Walker.

    Science.gov (United States)

    Nicholl, Anthony R J; Busnardo, Renato G; da Silva, Luciana M; Rodrigues, Ana Cláudia T; Luz, Fernanda R C; Bentim, Claudia C G; Medola, Fausto O; Paschoarelli, Luis C

    2015-01-01

    This study aimed to report on the design and development of a low cost Reverse Walker through a participative development cycle with people undergoing rehabilitation. The creation and fundamentals of the concept are described, as well as the development of prototypes and their provision to subjects with mobility problems. The Reverse Walker benefits the user by promoting a more upright posture and favoring the development of postural balance. Enhancing the mobility of people with disabilities may benefit their independence, social participation and quality of life.

  14. Integral constraints on perturbations of Robertson-Walker cosmologies

    International Nuclear Information System (INIS)

    Ellis, G.F.R.; Jaklitsch, M.J.

    1989-01-01

    Integral constraints occur in the case of spherically symmetric inhomogeneities in Robertson-Walker universes, and (according to Traschen) in the case of general perturbations of these models. It is shown that these constraints are the same in the case of spherical symmetry, and they are interpreted as 'fitting conditions', that is, as constraints on the background Robertson-Walker model rather than on the nature of inhomogeneities. These integral constraints significantly affect the interpretation of anisotropies in the cosmic microwave background radiation. 22 refs

  15. Design and Control of JAIST Active Robotic Walker

    OpenAIRE

    Lee, Geunho; Ohnuma, Takanori; Chong, Nak Young

    2010-01-01

    This paper presents the design and control of a novel assistive robotic walker that we call “JAIST activerobotic walker (JARoW)”. JARoW is developed to providepotential users with sufficient ambulatory capability in anefficient、 cost-effective way. Specifically、 our focus is placed on how to allow easier maneuverability by creating a natural interface between the user and JARoW. For the purpose、 we develop a rotating infrared sensor to detect the user’s lower limb movement. The implementation...

  16. Infinitesimal conformal closed transformations of de Sitter and Robertson-Walker cosmological spaces

    International Nuclear Information System (INIS)

    Sakoto, Moussa

    1976-01-01

    The infinitesimal conformal closed transfromations of de Sitter and Robertson-Walker cosmological spaces are determined and an interesting property of the current lines for Robertson-Walker spaces is given [fr

  17. The role of walkers' needs and expectations in supporting maintenance of attendance at walking groups: a longitudinal multi-perspective study of walkers and walk group leaders.

    Science.gov (United States)

    Kassavou, Aikaterini; Turner, Andrew; French, David P

    2015-01-01

    There is good evidence that when people's needs and expectations regarding behaviour change are met, they are satisfied with that change, and maintain those changes. Despite this, there is a dearth of research on needs and expectations of walkers when initially attending walking groups and whether and how these needs and expectations have been satisfied after a period of attendance. Equally, there is an absence of research on how people who lead these groups understand walkers' needs and walk leaders' actions to address them. The present study was aimed at addressing both of these gaps in the research. Two preliminary thematic analyses were conducted on face-to-face interviews with (a) eight walkers when they joined walking groups, five of whom were interviewed three months later, and (b) eight walk leaders. A multi-perspective analysis building upon these preliminary analyses identified similarities and differences within the themes that emerged from the interviews with walkers and walk leaders. Walkers indicated that their main needs and expectations when joining walking groups were achieving long-term social and health benefits. At the follow up interviews, walkers indicated that satisfaction with meeting similar others within the groups was the main reason for continued attendance. Their main source of dissatisfaction was not feeling integrated in the existing walking groups. Walk leaders often acknowledged the same reasons for walkers joining and maintaining attendance at walking. However, they tended to attribute dissatisfaction and drop out to uncontrollable environmental factors and/or walkers' personalities. Walk leaders reported a lack of efficacy to effectively address walkers' needs. Interventions to increase retention of walkers should train walk leaders with the skills to help them modify the underlying psychological factors affecting walkers' maintenance at walking groups. This should result in greater retention of walkers in walking groups, thereby

  18. The role of walkers' needs and expectations in supporting maintenance of attendance at walking groups: a longitudinal multi-perspective study of walkers and walk group leaders.

    Directory of Open Access Journals (Sweden)

    Aikaterini Kassavou

    Full Text Available There is good evidence that when people's needs and expectations regarding behaviour change are met, they are satisfied with that change, and maintain those changes. Despite this, there is a dearth of research on needs and expectations of walkers when initially attending walking groups and whether and how these needs and expectations have been satisfied after a period of attendance. Equally, there is an absence of research on how people who lead these groups understand walkers' needs and walk leaders' actions to address them. The present study was aimed at addressing both of these gaps in the research.Two preliminary thematic analyses were conducted on face-to-face interviews with (a eight walkers when they joined walking groups, five of whom were interviewed three months later, and (b eight walk leaders. A multi-perspective analysis building upon these preliminary analyses identified similarities and differences within the themes that emerged from the interviews with walkers and walk leaders.Walkers indicated that their main needs and expectations when joining walking groups were achieving long-term social and health benefits. At the follow up interviews, walkers indicated that satisfaction with meeting similar others within the groups was the main reason for continued attendance. Their main source of dissatisfaction was not feeling integrated in the existing walking groups. Walk leaders often acknowledged the same reasons for walkers joining and maintaining attendance at walking. However, they tended to attribute dissatisfaction and drop out to uncontrollable environmental factors and/or walkers' personalities. Walk leaders reported a lack of efficacy to effectively address walkers' needs.Interventions to increase retention of walkers should train walk leaders with the skills to help them modify the underlying psychological factors affecting walkers' maintenance at walking groups. This should result in greater retention of walkers in walking

  19. Mieren in Veluwebermen: soortenrijkdom en aanbevelingen voor beheer (Hymenoptera: Formicidae).

    NARCIS (Netherlands)

    Noordijk, J.; Boer, P.

    2007-01-01

    Ants in roadside verges on the Veluwe: species richness and recommendations for management (Hymenoptera: Formicidae) Highway verges in the Veluwe region contain some well developed nutrient poor plant communities, like grasslands, grey hair grass vegetation and heather vegetation. These places

  20. New faunistic data on the family Braconidae (Hymenoptera from Korea

    Directory of Open Access Journals (Sweden)

    Tae-Ho An

    2014-12-01

    Full Text Available Twenty-one species of the four genera in the family Braconidae (Hymenoptera are reported for the first time in Korea. These species belong to the subfamily Euphorinae (Braconidae. Faunistic and distribution data are included.

  1. 78 FR 25234 - Proposed Establishment of Class E Airspace; Walker, MN

    Science.gov (United States)

    2013-04-30

    ...-0266; Airspace Docket No. 13-AGL-11] Proposed Establishment of Class E Airspace; Walker, MN AGENCY... action proposes to establish Class E airspace at Walker, MN. Controlled airspace is necessary to accommodate new Standard Instrument Approach Procedures (SIAP) at Walker Municipal Airport. The FAA is taking...

  2. 21 CFR 890.3790 - Cane, crutch, and walker tips and pads.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cane, crutch, and walker tips and pads. 890.3790 Section 890.3790 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES..., crutch, and walker tips and pads. (a) Identification. Cane, crutch, and walker tips and pads are rubber...

  3. A checklist of Ropalidiini wasps (Hymenoptera: Vespidae: Polistinae in Indochina

    Directory of Open Access Journals (Sweden)

    Pham Phong Huy

    2014-01-01

    Full Text Available As a basis for intensive study of the taxonomy and biogeography of Ropalidiini wasps in Indochina (Hymenoptera: Vespidae: Polistinae, a checklist of Ropalidiini wasps (Hymenoptera: Vespidae is presented. A total of 57 Ropalidiini species and subspecies belonging to three genera from Indochina are listed, together with information of the type material deposited in the Natural History Collection, Ibaraki University, Japan (IUNH and the Institute of Ecology and Biological Resources (IEBR. References of their distribution in Indochina are also provided.

  4. Finding the Right Formula: Edwin H. Walker Jr

    Science.gov (United States)

    Keels, Crystal L.

    2005-01-01

    Edwin H. Walker Jr earned his doctorate in chemistry at age 27 and has barely looked back. With 13 publications under his belt before coming out of graduate school, he has also given more than 20 poster presentations in national venues, most recently at the American Chemical Society. He can also include securing a half-million-dollar National…

  5. Spruce aphid (Elatobium abietinum Walker) (Hemiptera: Aphididae) [Chapter XXIV

    Science.gov (United States)

    Ann M. Lynch

    2014-01-01

    Elatobium abietinum Walker is a spruce-feeding aphid that in Europe is referred to as the green spruce aphid (Day et al., 1998a) (Fig. 1). However, in North America E. abietinum is known simply as the spruce aphid, while the common name "green spruce aphid" refers to a different species, Cinara fornacula Hottes (Hemiptera: Aphididae) (http://www.entsoc.org/...

  6. Future null infinity of Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Moreschi, O.M.

    1988-08-01

    The future null infinity for all non-contracting Robertson-Walker space time is studied systematically. A theorem is proved which establishes the expected relation between the nature of J + and the appearance or absence of cosmic event horizons. (author). 7 refs, 1 tab

  7. Network formation determined by the diffusion process of random walkers

    International Nuclear Information System (INIS)

    Ikeda, Nobutoshi

    2008-01-01

    We studied the diffusion process of random walkers in networks formed by their traces. This model considers the rise and fall of links determined by the frequency of transports of random walkers. In order to examine the relation between the formed network and the diffusion process, a situation in which multiple random walkers start from the same vertex is investigated. The difference in diffusion rate of random walkers according to the difference in dimension of the initial lattice is very important for determining the time evolution of the networks. For example, complete subgraphs can be formed on a one-dimensional lattice while a graph with a power-law vertex degree distribution is formed on a two-dimensional lattice. We derived some formulae for predicting network changes for the 1D case, such as the time evolution of the size of nearly complete subgraphs and conditions for their collapse. The networks formed on the 2D lattice are characterized by the existence of clusters of highly connected vertices and their life time. As the life time of such clusters tends to be small, the exponent of the power-law distribution changes from γ ≅ 1-2 to γ ≅ 3

  8. Walker-type velocity oscillations of magnetic domain walls

    International Nuclear Information System (INIS)

    Vella-Coleiro, G.P.

    1976-01-01

    We report stroboscopic observations of the radial motion of a magnetic bubble domain wall in an epitaxial LuGdAl iron garnet film. At high drive fields, initial velocities up to 9500 cm/sec were measured, and the domain wall was observed to move backwards during the field pulse, in agreement with calculations based on the Walker model

  9. Nursery Pest Management of Phytolyma lata Walker (Scott) Attack ...

    African Journals Online (AJOL)

    The establishment of plantations of Milicia excelsa has been constrained by the gall-forming psyllid Phytolyma lata Walker (Scott) that causes extensive damage to young plants. We present findings of an experiment aimed at preventing Phytolyma attack on Milicia seedlings in the nursery using chemical control and ...

  10. Dandy-Walker syndrome together with occipital encephalocele.

    Science.gov (United States)

    Cakmak, A; Zeyrek, D; Cekin, A; Karazeybek, H

    2008-08-01

    Dandy-Walker malformation is an anomaly characterized by dysgenesis of the foramina of Magendie and Lushka in the upper 4(th) ventricle, hypoplasia of the cerebellar vermis and agenesis of the corpus callosum. Encephalocele is diagnosed from the calvarium defect, cerebrospinal fluid (CSF) and herniation of the meninges. It is the rarest neural tube defect. A 7 x 9 cm encephalocele was found on physical examination of a 6-day old baby boy patient. From cranial magnetic resonance, it was seen that the posterior fossa was enlarged with cysts and there was agenesis of the vermis. A connection was established between the ventricle and the development of cysts on the posterior fossa. These findings were evaluated as significant from the aspect of Dandy-Walker malformation. The extension of the bone defect in the left occipital area towards the posterior, and the cranio-caudal diameter reaching 9 cm was seen to be in accordance with encephalocele. It is rare for Dandy-Walker syndrome to occur together with occipital encephalocele. The authors present a case of Dandy-Walker syndrome together with occipital encephalocele.

  11. A stochastic DNA walker that traverses a microparticle surface

    Science.gov (United States)

    Jung, C.; Allen, P. B.; Ellington, A. D.

    2016-02-01

    Molecular machines have previously been designed that are propelled by DNAzymes, protein enzymes and strand displacement. These engineered machines typically move along precisely defined one- and two-dimensional tracks. Here, we report a DNA walker that uses hybridization to drive walking on DNA-coated microparticle surfaces. Through purely DNA:DNA hybridization reactions, the nanoscale movements of the walker can lead to the generation of a single-stranded product and the subsequent immobilization of fluorescent labels on the microparticle surface. This suggests that the system could be of use in analytical and diagnostic applications, similar to how strand exchange reactions in solution have been used for transducing and quantifying signals from isothermal molecular amplification assays. The walking behaviour is robust and the walker can take more than 30 continuous steps. The traversal of an unprogrammed, inhomogeneous surface is also due entirely to autonomous decisions made by the walker, behaviour analogous to amorphous chemical reaction network computations, which have been shown to lead to pattern formation.

  12. Dandy-Walker malformation | Hamid | Egyptian Journal of Medical ...

    African Journals Online (AJOL)

    Dandy-Walker malformation is a rare congenital malformation and involves the cerebellum and fourth ventricle. The condition is characterized by agenesis or hypoplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle, and enlargement of the posterior fossa. A large number of concomitant problems may be ...

  13. 75 FR 35265 - Safety Standard for Infant Walkers: Final Rule

    Science.gov (United States)

    2010-06-21

    ... are walking (usually 6 to 15 months old). ASTM F 977-07 defines ``walker'' as ``a mobile unit that... attached to rigid trays. The trays are fastened to bases that have wheels or casters to make them mobile.../jumping. Occupant retention--intended to prevent entrapment by setting requirements for leg openings. The...

  14. Construction of calibration pads facility, Walker Field, Grand Junction, Colorado

    International Nuclear Information System (INIS)

    Ward, D.L.

    1978-08-01

    A gamma-ray spectrometer facility was completed at Walker Field Airport, Grand Junction, Colorado, in November 1976. This report describes spectrometers and their calibration, the construction of the spectrometer facility, the radioelement concentrations, procedures for using the facilites, and environmental considerations

  15. Quantization of Robertson-Walker geometry coupled to fermionic matter

    International Nuclear Information System (INIS)

    Christodoulakis, T.; Zanelli, J.

    1983-06-01

    A Robertson-Walker universe coupled to a spin 1/2 Dirac field is quantized following Dirac's formalism for constrained Hamiltonian systems. It is found that in nearly all cases it can be asserted that the universe avoids the collapse. (author)

  16. Philip Glass, Scott Walker ja Sigur Ros! / Immo Mihkelson

    Index Scriptorium Estoniae

    Mihkelson, Immo, 1959-

    2007-01-01

    Pimedate Ööde 11. filmifestivali muusikafilme - Austraalia "Glass: Philipi portree 12 osas" (rež. Scott Hicks), Islandi "Sigur Ros kodus" (rež. Dean DeBois), Suurbritannia "Scott Walker: 30 Century Man" (rež. Stephen Kijak)

  17. Fibreglass Total Contact Casting, Removable Cast Walkers, and Irremovable Cast Walkers to Treat Diabetic Neuropathic Foot Ulcers: A Health Technology Assessment

    Science.gov (United States)

    Costa, Vania; Tu, Hong Anh; Wells, David; Weir, Mark; Holubowich, Corinne; Walter, Melissa

    2017-01-01

    Background Diabetic neuropathic foot ulcers are a risk factor for lower leg amputation. Many experts recommend offloading with fibreglass total contact casting, removable cast walkers, and irremovable cast walkers as a way to treat these ulcers. Methods We completed a health technology assessment, which included an evaluation of clinical benefits and harms, value for money, and patient preferences for offloading devices. We performed a systematic literature search on August 17, 2016, to identify randomized controlled trials that compared fibreglass total contact casting, removable cast walkers, and irremovable cast walkers with other treatments (offloading or non-offloading) in patients with diabetic neuropathic foot ulcers. We developed a decision-analytic model to assess the cost-effectiveness of fibreglass total contact casting, removable cast walkers, and irremovable cast walkers, and we conducted a 5-year budget impact analysis. Finally, we interviewed people with diabetes who had lived experience with foot ulcers, asking them about the different offloading devices and the factors that influenced their treatment choices. Results We identified 13 randomized controlled trials. The evidence suggests that total contact casting, removable cast walkers, and irremovable cast walkers are beneficial in the treatment of neuropathic, noninfected foot ulcers in patients with diabetes but without severe peripheral arterial disease. Compared to removable cast walkers, ulcer healing was improved with total contact casting (moderate quality evidence; risk difference 0.17 [95% confidence interval 0.00–0.33]) and irremovable cast walkers (low quality evidence; risk difference 0.21 [95% confidence interval 0.01–0.40]). We found no difference in ulcer healing between total contact casting and irremovable cast walkers (low quality evidence; risk difference 0.02 [95% confidence interval −0.11–0.14]). The economic analysis showed that total contact casting and irremovable

  18. Natural history of interaction between Meteorus sp. Haliday, 1835 (Hymenoptera: Braconidae) and its hyperparasitoid Toxeumella albipes Girault, 1913 (Hymenoptera: Pteromalidae).

    Science.gov (United States)

    Sobczak, J F; Maia, D P; Moura, J C M S; Costa, V A; Vasconcellos-Neto, J

    2012-02-01

    Some parasitoids build a cocoon mass that hangs in the host body until the adults emergence, which is an advantage against attack by predators who troll the vegetation in search of prey. However, such behaviour is not effective against the hyperparasitoid attacks. This study reports the interaction between the caterpillar Manduca sexta Linnaeus, 1763 (Lepidoptera, Sphingidae) parasitised by Meteorus sp. (Hymenoptera, Braconidae) larvae and its hyperparasitoid Toxeumella albipes (Hymenoptera, Pteromalidae). This is the first description of the attack and oviposition of T. albipes.

  19. Revalidation of Ceresa terminalis walker and its placement in Stictocephala Stål (Hemiptera, Membracidae Revalidação de Ceresa terminalis walker e sua alocação em Stictocephala Stål (Hemiptera, Membracidae

    Directory of Open Access Journals (Sweden)

    Gabriel S. de Andrade

    2005-12-01

    Full Text Available Ceresa terminalis Walker, 1851 is reinstated and transferred to Stictocephala Stål, 1869: Stictocephala terminalis (Walker, 1851 sp. rev., comb. nov.Ceresa terminalis Walker, 1851 é revalidada e transferida para Stictocephala Stål, 1869: Stictocephala terminalis (Walker, 1851 sp. rev., comb. nov.

  20. Anthropometric characteristics of top-class Olympic race walkers.

    Science.gov (United States)

    Gomez-Ezeiza, Josu; Tam, Nicholas; Torres-Unda, Jon; Granados, Cristina; Santos-Concejero, Jordan

    2018-04-20

    Typical training programmes in elite race walkers involve high training volumes at low and moderate intensities, which have been reported to induce functional and structural adaptations at an anthropometric level. Since anthropometrical variables are closely related to movement efficiency and performance in endurance events, the aim of this study was to describe the anthropometric profile of world-class race walkers. Twenty-nine world-class race walkers (21 men & 8 women) participated in this study. Anthropometric characteristics, including height, body mass, eight skinfolds, five girths and four bone breadths were measured. Body composition, somatotype, somatotype dispersion mean, somatotype attitudinal mean and height to weight ratio, as well as skinfolds extremity to trunk ratio were also calculated. Mean height, body mass and body mass index were 177.1 ± 7.1 cm, 66.4 ± 5.8 kg, and21.2±1.3kg·m2 formenand165.6±4.5cm,53.6±3.7kg,and19.6±1.6kg·m2for women, respectively. Women presented greater body fat content (6.7 ± 0.6 vs. 12.2 ± 0.8%; very large effect), less muscle mass (65.6 ± 4.6 vs. 61.6 ± 2.6 kg; large effect), and were more endomorphic (large effect) than men. Men specialists in 20-km showed greater muscle mass (66.7 ± 4.9 vs. 64.4 ± 4.3 kg; moderate effect), and slightly higher skinfolds, girths, body fat content and were more mesomorphic than 50-km specialists (moderate effect). The present study expands the limited knowledge on the anthropometric characteristics and somatotype elements of elite top-class race walkers. The characterisation of the morphology of elite race walkers provides coaches a reference values to control the training development of the race walker, as well as providing reference values to improve talent identification.

  1. Quantum Tunneling and Chaos in Classical Scale Walkers

    Science.gov (United States)

    Su, Jenny; Dijksman, Joshua; Ward, Jeremy; Behringer, Robert

    2014-03-01

    We study the behavior of `walkers' small droplets bouncing on a fluid layer vibrated at amplitudes just below the onset of Faraday instability. It was shown recently that despite their macroscopic size, the droplet dynamics are stochastic in nature and reminiscent of the dual particle-wave dynamics in the realm of quantum mechanics (Couder PRL 2006). We use these walkers to study how chaos, which is macroscopically unpredictable, will manifest in a quantum setting. Pecora showed in 2011 that tunneling for particles that have a chaotic ground state is different from tunneling for particles with a regular ground state (PRE 2011). In the experiment we gather data that illustrates the particle trajectory and tunneling behavior as particles transition across the barrier in the double well system with both integrable and chaotic shapes.

  2. The paternal-sex-ratio (PSR) chromosome in natural populations of Nasonia (Hymenoptera Chalcidoidea)

    NARCIS (Netherlands)

    Beukeboom, L.W.; Werren, J.H.

    2000-01-01

    Selfish genetic elements may be important in promoting evolutionary change. Paternal sex ratio (PSR) is a selfish B chromosome that causes all-male families in the haplodiploid parasitic wasp Nasonia vitripennis, by inducing paternal genome loss in fertilized eggs. The natural distribution and

  3. Terrain Interaction With The Quarter Scale Beam Walker

    Science.gov (United States)

    Chun, Wendell H.; Price, R. S.; Spiessbach, Andrew J.

    1990-03-01

    Frame walkers are a class of mobile robots that are robust and capable mobility platforms. Variations of the frame walker robot are in commercial use today. Komatsu Ltd. of Japan developed the Remotely Controlled Underwater Surveyor (ReCUS) and Normed Shipyards of France developed the Marine Robot (RM3). Both applications of the frame walker concept satisfied robotic mobility requirements that could not be met by a wheeled or tracked design. One vehicle design concept that falls within this class of mobile robots is the walking beam. A one-quarter scale prototype of the walking beam was built by Martin Marietta to evaluate the potential merits of utilizing the vehicle as a planetary rover. The initial phase of prototype rover testing was structured to evaluate the mobility performance aspects of the vehicle. Performance parameters such as vehicle power, speed, and attitude control were evaluated as a function of the environment in which the prototype vehicle was tested. Subsequent testing phases will address the integrated performance of the vehicle and a local navigation system.

  4. Terrain interaction with the quarter scale beam walker

    Science.gov (United States)

    Chun, Wendell H.; Price, S.; Spiessbach, A.

    1990-01-01

    Frame walkers are a class of mobile robots that are robust and capable mobility platforms. Variations of the frame walker robot are in commercial use today. Komatsu Ltd. of Japan developed the Remotely Controlled Underwater Surveyor (ReCUS) and Normed Shipyards of France developed the Marine Robot (RM3). Both applications of the frame walker concept satisfied robotic mobility requirements that could not be met by a wheeled or tracked design. One vehicle design concept that falls within this class of mobile robots is the walking beam. A one-quarter scale prototype of the walking beam was built by Martin Marietta to evaluate the potential merits of utilizing the vehicle as a planetary rover. The initial phase of prototype rover testing was structured to evaluate the mobility performance aspects of the vehicle. Performance parameters such as vehicle power, speed, and attitude control were evaluated as a function of the environment in which the prototype vehicle was tested. Subsequent testing phases will address the integrated performance of the vehicle and a local navigation system.

  5. On the existence of perturbed Robertson-Walker universes

    International Nuclear Information System (INIS)

    D'Eath, P.D.

    1976-01-01

    Solutions of the full nonlinear field equations of general relativity near the Robertson-Walker universes are examined, together with their relation to linearized perturbations. A method due to Choquet-Bruhat and Deser is used to prove existence theorems for solutions near Robertson-Walker constraint data of the constraint equations on a spacelike hypersurface. These theorems allow one to regard the matter fluctuations as independent quantities, ranging over certain function spaces. In the k=-1 case the existence theory describes perturbations which may vary within uniform bounds throughout space. When k=+1 a modification of the method leads to a theorem which clarifies some unusual features of these constraint perturbations. The k=0 existence theorem refers only to perturbations which die away at large distances. The connection between linearized constraint solutions and solutions of the full constraints is discussed. For k= +- 1 backgrounds, solutions of the linearized constraints are analyzed using transverse-traceless decompositions of symmetric tensors. Finally the time-evolution of perturbed constraint data and the validity of linearized perturbation theory for Robertson-Walker universes are considered

  6. Cochlear implantation in patient with Dandy-walker syndrome.

    Science.gov (United States)

    de Oliveira, Adriana Kosma Pires; Hamerschmidt, Rogerio; Mocelin, Marcos; Rezende, Rodrigo K

    2012-07-01

     Dandy Walker Syndrome is a congenital abnormality in the central nervous system, characterized by a deficiency in the development of middle cerebelar structures, cystic dilatation of the posterior pit communicating with the fourth ventricle and upward shift of the transverse sinuses, tentorium and dyes. Among the clinical signs are occipital protuberances, a progressive increase of the skull, bowing before the fontanels, papilledema, ataxia, gait disturbances, nystagmus, and intellectual impairment.  To describe a case of female patient, 13 years old with a diagnosis of this syndrome and bilateral hearing loss underwent cochlear implant surgery under local anesthesia and sedation.  CGS, 13 years old female was referred to the Otolaryngological Department of Otolaryngology Institute of Parana with a diagnosis of "Dandy-Walker syndrome" for Otolaryngological evaluation for bilateral hearing loss with no response to the use of hearing aids. Final Comments: The field of cochlear implants is growing rapidly. We believe that the presence of Dandy-Walker syndrome cannot be considered a contraindication to the performance of cochlear implant surgery, and there were no surgical complications due to neurological disorders with very favorable results for the patient who exhibits excellent discrimination. It has less need for lip reading with improvement in speech quality.

  7. Cochlear implantation in patient with Dandy-walker syndrome

    Directory of Open Access Journals (Sweden)

    Oliveira, Adriana Kosma Pires de

    2012-01-01

    Full Text Available Introduction: Dandy Walker Syndrome is a congenital abnormality in the central nervous system, characterized by a deficiency in the development of middle cerebelar structures, cystic dilatation of the posterior pit communicating with the fourth ventricle and upward shift of the transverse sinuses, tentorium and dyes. Among the clinical signs are occipital protuberances, a progressive increase of the skull, bowing before the fontanels, papilledema, ataxia, gait disturbances, nystagmus, and intellectual impairment. Objectives: To describe a case of female patient, 13 years old with a diagnosis of this syndrome and bilateral hearing loss underwent cochlear implant surgery under local anesthesia and sedation. Case Report: CGS, 13 years old female was referred to the Otolaryngological Department of Otolaryngology Institute of Parana with a diagnosis of "Dandy-Walker syndrome" for Otolaryngological evaluation for bilateral hearing loss with no response to the use of hearing aids. Final Comments: The field of cochlear implants is growing rapidly. We believe that the presence of Dandy-Walker syndrome cannot be considered a contraindication to the performance of cochlear implant surgery, and there were no surgical complications due to neurological disorders with very favorable results for the patient who exhibits excellent discrimination. It has less need for lip reading with improvement in speech quality.

  8. [Active and safe with wheeled walkers : Pilot study on feasibility of mobility exercises for wheeled walker users].

    Science.gov (United States)

    Pflaum, Marina; Lang, Frieder R; Freiberger, Ellen

    2016-07-01

    The number of older people with mobility impairments using wheeled walkers is increasing; however, the handling of these walking aids is often ineffective. Moreover, age-associated functional loss, environmental demands and fear of falling may additionally challenge mobility. The new training program "Active and safe with wheeled walkers" aims to enhance skills and to improve mobility. The present pilot study was carried out to assess the feasibility of the training as well as to identify training effects and methodological insights for further research. The study was carried out with 28 wheeled walker users (age 68-91 years) in assisted living facilities using a pre-post design. Of the participants 13 persons were trained for 10 weeks (90 min, twice a week) and 15 persons served as a control group. Data were collected on functional mobility, hand strength, leg strength, balance, walker handling and fear of falling. The drop-out rate for the training was 38 % due to health concerns (n = 2), lack of time (n = 1) and changes in health status independent of training (n = 3). Medium to large effects were detected. Data regarding the recruitment strategy and the acceptance of individual exercises are available. The results indicate a good feasibility and effectiveness of the training. The simple accessibility of the training was conducive for the regular participation. The everyday relevance of the results and the lack of comparable interventions suggest that further research efforts be carried out. Recruitment strategies, training requirements and data collection methods need to be optimized.

  9. LCP method for a planar passive dynamic walker based on an event-driven scheme

    Science.gov (United States)

    Zheng, Xu-Dong; Wang, Qi

    2018-06-01

    The main purpose of this paper is to present a linear complementarity problem (LCP) method for a planar passive dynamic walker with round feet based on an event-driven scheme. The passive dynamic walker is treated as a planar multi-rigid-body system. The dynamic equations of the passive dynamic walker are obtained by using Lagrange's equations of the second kind. The normal forces and frictional forces acting on the feet of the passive walker are described based on a modified Hertz contact model and Coulomb's law of dry friction. The state transition problem of stick-slip between feet and floor is formulated as an LCP, which is solved with an event-driven scheme. Finally, to validate the methodology, four gaits of the walker are simulated: the stance leg neither slips nor bounces; the stance leg slips without bouncing; the stance leg bounces without slipping; the walker stands after walking several steps.

  10. Influence of temperature on current-induced domain wall motion and its Walker breakdown

    International Nuclear Information System (INIS)

    Fan, Lvchao; Hu, Jingguo; Su, Yuanchang; Zhu, Jinrong

    2016-01-01

    The current-driven domain wall propagation along a thin ferromagnetic strip with thermal field is studied by means of micromagnetic simulations. The results show that the velocity of domain wall is almost independent of temperature until Walker breakdown happened. However the thermal field can suppress Walker breakdown and makes domain wall move faster. Further analysis indicates that the thermal field tends to keep the out-of-plane magnetic moment of the domain wall stay in high value, which can promote domain wall motion and suppress the Walker breakdown by breaking the period of domain wall transformation. - Highlights: • Influences of temperature on the displacement and the velocity of DW are shown. • The suppression of Walker breakdown by temperature is given. • The reason for suppressing Walker breakdown is analyzed. • The breaking transformation period of Walker breakdown by temperature is given.

  11. Ovarian egg morphology in chalcidoid wasps (Hymenoptera: Chalcidoidea parasitizing gall wasps (Hymenoptera: Cynipidae

    Directory of Open Access Journals (Sweden)

    Vårdal, H.

    2016-06-01

    Full Text Available We provide morphological egg data of 26 species of 5 chalcidoid families associated with cynipid galls (Hymenoptera: Cynipidae from western Palaearctic, including the first egg data for the family Ormyridae. Adult chalcidoid species were reared from galls, and eggs obtained from dissected female ovaries were examined using scanning electron microscopy (SEM. The shape of the eggs varies from oval to elongate and tapered at both ends. Eggs of Eurytomidae as well as some Eulophidae, Eupelmidae and Pteromalidae are equipped with a peduncle at the anterior end. We found a positive correlation between long eggs and long ovipositors and confirmed the expectation that eggs of endoparasitoids are generally shorter and narrower than eggs of ectoparasitoids. We were able to locate the sperm entrance or micropyle at the anterior pole of eggs of several species. It is situated at the anterior end of the egg and at the end of the peduncle when present. In addition, the eggshells of the endoparasitoid Sycophila biguttata (Swederus, 1795 (Hymenoptera: Eurytomidae and the ectoparasitoid Cecidostiba fungosa (Geoffroy, 1785 (Hymenoptera: Pteromalidae, are for the first time described.En el presente trabajo se aportan datos morfol.gicos del huevo de 26 especies del Paleártico occidental pertenecientes a 5 familias de Chalcidoidea asociadas con agallas de cinípidos (Hymenoptera: Cynipidae, incluyendo los primeros datos del huevo de especies de Ormyridae. Los ejemplares adultos de las especies estudiadas fueron obtenidos por emergencia de agallas en laboratorio, los ovarios de las hembras diseccionados para obtener los huevos, que fueron finalmente estudiados utilizando técnicas de microscopía electronica de barrido. La forma de los huevos estudiados varía de ovalada a alargada y ahusada en ambos extremos. Los huevos de Eurytomidae, así como algunos de Eulophidae, Eupelmidae y Pteromalidae están provistos de un pedúnculo en el extremo anterior. Se encontr

  12. Determination of Opiinae parasitoids (Hymenoptera: Braconidae) associated with crop infesting Bactrocera spp. (Diptera: Tephritidae) using COI and Cyt b sequences

    Science.gov (United States)

    Shariff, Safiah; Yaakop, Salmah; Zain, Badrul Munir Md.

    2013-11-01

    Members of the Opiinae subfamily (Hymenoptera: Braconidae) are well known as important parasitoids of fruit fly larvae (Diptera: Tephritidae). They are widely used as biological control agents of fruit flies, especially the Bactrocera Macquart species that infest fruits. In this study, the larvae of fruit flies were collected from infested crops including star fruit, guava, wax apple and ridge gourd. The parasitized larvae were then reared under laboratory conditions until emergence of the adult parasitoids. Additionally, Malaise trap also was used to collect parasitoid species. The general concept of the multiplex PCR has been performed is to amplify two mitochondrial DNA markers, namely cytochrome oxidase subunit I (COI) and cytochrome b (Cyt b) simultaneously. Therefore, the lengthy process of reaction will be reduced. The status of the fruit fly species has also been confirmed by using COI marker on the early stage of the larvae. Maximum parsimony (MP) and Bayesian Inference (BI) were implemented to help and support the identification of Opiinae species. The result obtained from this study showed three parasitoid genera of the Opiinae viz. Fopius Wharton, Psyttalia Walker and Diachasmimorpha Viereck. Each genus has been determined by clustering together in a similar clade according to their infested crops. Therefore, accurate determination of parasitoids and the fruit fries species was highly useful and necessary for successful biological control of Bactrocera species.

  13. Generalized Friedmann-Robertson-Walker metric and redundancy in the generalized Einstein equations

    International Nuclear Information System (INIS)

    Kao, W.F.; Pen, U.

    1991-01-01

    A nontrivial redundancy relation, due to the differential structure of the gravitational Bianchi identity as well as the symmetry of the Friedmann-Robertson-Walker metric, in the gravitational field equation is clarified. A generalized Friedmann-Robertson-Walker metric is introduced in order to properly define a one-dimensional reduced problem which offers an alternative approach to obtain the gravitational field equations on Friedmann-Robertson-Walker spaces

  14. A Motion Control of a Robotic Walker for Continuous Assistance during Standing, Walking and Seating Operation

    OpenAIRE

    Chugo, Daisuke; Takase, Kunikatsu

    2010-01-01

    In this paper, we develop an active walker system for standing, walking and seating operation continuously which cooperates the developed standing assistance system with safety and stability. For realizing these conditions, our walker coordinates the assisting position cooperating the standing assistance manipulator according to the posture of the patient. Furthermore, our walker adjusts a seating position when the patient sit down which has high risk for falling down. Using our proposed syst...

  15. Head capsule characters in the Hymenoptera and their phylogenetic implications

    Directory of Open Access Journals (Sweden)

    Lars Vilhelmsen

    2011-09-01

    Full Text Available The head capsule of a taxon sample of three outgroup and 86 ingroup taxa is examined for characters of possible phylogenetic significance within Hymenoptera. 21 morphological characters are illustrated and scored, and their character evolution explored by mapping them onto a phylogeny recently produced from a large morphological data set. Many of the characters are informative and display unambiguous changes. Most of the character support demonstrated is supportive at the superfamily or family level. In contrast, only few characters corroborate deeper nodes in the phylogeny of Hymenoptera.

  16. Effects of walker gender and observer gender on biological motion walking direction discrimination.

    Science.gov (United States)

    Yang, Xiaoying; Cai, Peng; Jiang, Yi

    2014-09-01

    The ability to recognize the movements of other biological entities, such as whether a person is walking toward you, is essential for survival and social interaction. Previous studies have shown that the visual system is particularly sensitive to approaching biological motion. In this study, we examined whether the gender of walkers and observers influenced the walking direction discrimination of approaching point-light walkers in fine granularity. The observers were presented a walker who walked in different directions and were asked to quickly judge the walking direction (left or right). The results showed that the observers demonstrated worse direction discrimination when the walker was depicted as male than when the walker was depicted as female, probably because the observers tended to perceive the male walkers as walking straight ahead. Intriguingly, male observers performed better than female observers at judging the walking directions of female walkers but not those of male walkers, a result indicating perceptual advantage with evolutionary significance. These findings provide strong evidence that the gender of walkers and observers modulates biological motion perception and that an adaptive perceptual mechanism exists in the visual system to facilitate the survival of social organisms. © 2014 The Institute of Psychology, Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  17. Anisotropic evolution of 5D Friedmann-Robertson-Walker spacetime

    International Nuclear Information System (INIS)

    Middleton, Chad A.; Stanley, Ethan

    2011-01-01

    We examine the time evolution of the five-dimensional Einstein field equations subjected to a flat, anisotropic Robertson-Walker metric, where the 3D and higher-dimensional scale factors are allowed to dynamically evolve at different rates. By adopting equations of state relating the 3D and higher-dimensional pressures to the density, we obtain an exact expression relating the higher-dimensional scale factor to a function of the 3D scale factor. This relation allows us to write the Friedmann-Robertson-Walker field equations exclusively in terms of the 3D scale factor, thus yielding a set of 4D effective Friedmann-Robertson-Walker field equations. We examine the effective field equations in the general case and obtain an exact expression relating a function of the 3D scale factor to the time. This expression involves a hypergeometric function and cannot, in general, be inverted to yield an analytical expression for the 3D scale factor as a function of time. When the hypergeometric function is expanded for small and large arguments, we obtain a generalized treatment of the dynamical compactification scenario of Mohammedi [Phys. Rev. D 65, 104018 (2002)] and the 5D vacuum solution of Chodos and Detweiler [Phys. Rev. D 21, 2167 (1980)], respectively. By expanding the hypergeometric function near a branch point, we obtain the perturbative solution for the 3D scale factor in the small time regime. This solution exhibits accelerated expansion, which, remarkably, is independent of the value of the 4D equation of state parameter w. This early-time epoch of accelerated expansion arises naturally out of the anisotropic evolution of 5D spacetime when the pressure in the extra dimension is negative and offers a possible alternative to scalar field inflationary theory.

  18. Primera cita de la Argentina de Ophelimus maskelli (Ashmead (Hymenoptera: Eulophidae y su parasitoide, Closterocerus chamaeleon (Girault (Hymenoptera: Eulophidae

    Directory of Open Access Journals (Sweden)

    Daniel A AQUINO

    2014-01-01

    Full Text Available Se cita por primera vez de la Argentina la presencia de la avispa galí - cola exótica Ophelimus maskelli (Ashmead (Hymenoptera: Eulophidae y su para - sitoide natural, Closterocerus chamaeleon (Girault (Hymenoptera: Eulophidae en Eucalyptus camaldulensis de la provincia de Buenos Aires. Ophelimus maskelli es una especie invasora de origen Australiano que ha sido reportada como plaga de los eucaliptos en numerosos países de Asia, Europa y América. Closterocerus chamaleon es un parasitoide exótico cuyo potencial como biocontrolador de O. maskelli está siendo evaluado en algunos países.

  19. Natural history of interaction between Meteorus sp. Haliday, 1835 (Hymenoptera: Braconidae and its hyperparasitoid Toxeumella albipes Girault, 1913 (Hymenoptera: Pteromalidae

    Directory of Open Access Journals (Sweden)

    JF Sobczak

    Full Text Available Some parasitoids build a cocoon mass that hangs in the host body until the adults emergence, which is an advantage against attack by predators who troll the vegetation in search of prey. However, such behaviour is not effective against the hyperparasitoid attacks. This study reports the interaction between the caterpillar Manduca sexta Linnaeus, 1763 (Lepidoptera, Sphingidae parasitised by Meteorus sp. (Hymenoptera, Braconidae larvae and its hyperparasitoid Toxeumella albipes (Hymenoptera, Pteromalidae. This is the first description of the attack and oviposition of T. albipes.

  20. Difficulties with Prenatal Diagnosis of the Walker-Warburg Syndrome

    International Nuclear Information System (INIS)

    Low, A.S.C.; Lee, S.L.; Tan, A.S.A.; Chan, D.K.L.; Chan, L.L.

    2005-01-01

    We describe a postnatally diagnosed case of Walker-Warburg syndrome - a form of congenital muscular dystrophy with lissencephaly and eye abnormalities. We reviewed the literature to highlight its clinico-radiological diagnostic features and discuss the difficulties encountered with prenatal diagnosis, especially in cases with no positive family history. An increased awareness of this rare but lethal condition, and a high index of suspicion during routine antenatal ultrasound, could prompt further advanced fetal ultrasonography and magnetic resonance imaging, and aid in timely prenatal diagnosis, management, and counseling. Brain/brainstem, congenital, magnetic resonance imaging, obstetrics, pediatrics, ultrasound

  1. Thomas James Walker (1835-1916): Surgeon and general practitioner.

    Science.gov (United States)

    Thomas, Martyn

    2018-02-01

    Thomas James Walker was a surgeon and general practitioner who worked in the city of Peterborough at a time when there were changes and innovations in the practice of medicine. After training in medicine and surgery at Edinburgh University, he qualified in London in 1857. He was a pioneer of laryngoscopy. He played an important role in introducing antiseptic surgery to the Peterborough Infirmary and was instrumental in the development of the operating theatre which opened in 1894. He was a philanthropist and collector of Roman and Saxon artefacts. In 1915, he was recognized as an outstanding member of the Peterborough community when he was offered the Freedom of the City.

  2. Difficulties with Prenatal Diagnosis of the Walker-Warburg Syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Low, A.S.C.; Lee, S.L.; Tan, A.S.A.; Chan, D.K.L.; Chan, L.L. [Singapore General Hospital (Singapore). Depts. of Diagnostic Radiology, Obstetrics and Gynecology and Neonatology

    2005-10-01

    We describe a postnatally diagnosed case of Walker-Warburg syndrome - a form of congenital muscular dystrophy with lissencephaly and eye abnormalities. We reviewed the literature to highlight its clinico-radiological diagnostic features and discuss the difficulties encountered with prenatal diagnosis, especially in cases with no positive family history. An increased awareness of this rare but lethal condition, and a high index of suspicion during routine antenatal ultrasound, could prompt further advanced fetal ultrasonography and magnetic resonance imaging, and aid in timely prenatal diagnosis, management, and counseling. Brain/brainstem, congenital, magnetic resonance imaging, obstetrics, pediatrics, ultrasound.

  3. Public and private space curvature in Robertson-Walker universes.

    Science.gov (United States)

    Rindler, W.

    1981-05-01

    The question is asked: what space curvature would a fundamental observer in an ideal Robertson-Walker universe obtain by direct local spatial measurements, i.e., without reference to the motion pattern of the other galaxies? The answer is that he obtains the curvatureK of his “private” space generated by all the geodesics orthogonal to his world line at the moment in question, and that ˜K is related to the usual curvatureK=k/R 2 of the “public” space of galaxies byK=K+H 2/c2, whereH is Hubble's parameter.

  4. Hymenoptera stings in Brazil: a neglected health threat in Amazonas State

    Directory of Open Access Journals (Sweden)

    Allyson Guimarães Costa

    Full Text Available Abstract INTRODUCTION: Hymenoptera injuries are commonly caused by stinging insects. In Amazonas state, Brazil, there is no information regarding distribution, profile, and systemic manifestations associated with Hymenoptera injuries. METHODS: This study aimed to identify risk factors for systemic manifestation using the Brazilian Notifiable Diseases Surveillance System (2007 to 2015. RESULTS: Half of Hymenoptera injuries were caused by bee stings. Hymenoptera injuries were concentrated in Manaus, and 13.36% of cases displayed systemic signs. Delayed medical assistance (4 to 12 hours presented four times more risk for systemic manifestations. CONCLUSIONS: Simple clinical observations and history of injury are critical information for prognostic improvement.

  5. A preliminary checklist of the ants (Hymenoptera: Formicidae) of ...

    African Journals Online (AJOL)

    A preliminary species checklist of the ants (Hymenoptera: Formicidae) of. Kakamega Forest, Western Kenya, is presented. The species list is based on specimens sampled from 1999 until 2009, which are deposited in the ant collection of the Zoological Research Museum Koenig, Bonn, Germany, and the Natural History ...

  6. Six new genera of Braconidae (Hymenoptera) from China

    NARCIS (Netherlands)

    Achterberg, van C.; Chen, X.

    2004-01-01

    Six new genera of the family Braconidae (Hymenoptera) from China are described and illustrated: two genera of the subfamily Agathidinae: Facilagathis gen. nov. (type species: F. spinulata spec. nov.) and Cremnoptoides gen. nov. (type species: Cremnops pappi Sharkey, 1994); one genus of the subfamily

  7. On the Hymenoptera (exclusive of the Anthophila and Formicidae)

    NARCIS (Netherlands)

    Cameron, P.

    1913-01-01

    Our knowledge of the Hymenoptera of the Island of Waigeu hitherto has been based on the material collected by Dr. A. R. Wallace and described by Mr. Frederick Smith in the Journal of the Linnean Society of London, 1863, pp. 6—48. Omitting the bees (5 species) and the ants (27 species) Smith

  8. An anocellar polistine wasp (Hymenoptera, Vespidae, Polistinae from Texas

    Directory of Open Access Journals (Sweden)

    Volker Lohrmann

    2016-12-01

    Full Text Available A remarkable teratological female of Polistes (Fuscopolistes dorsalis neotropicus Bequaert, 1940 (Vespidae: Polistinae is described and illustrated. The specimen lacks all three external dorsal ocelli but is normally developed in almost every other aspect. Additionally, similar findings in other Hymenoptera are briefly discussed, as are the consequences and the reasons that might cause the random loss of ocelli.

  9. Provisional host catalogue of Fig wasps (Hymenoptera, Chalcidoidea)

    NARCIS (Netherlands)

    Wiebes, J.T.

    1966-01-01

    INTRODUCTION In this catalogue — entitled "provisional" because our knowledge of the subject is still so evidently incomplete — all species of Ficus mentioned as hosts of fig wasps, are listed with the Hymenoptera Chalcidoidea reared from their receptacles. The names used for the Agaonidae are in

  10. De urntjeswesp Eumenes coronatus zoekt het hogerop (Hymenoptera: Vespidae)

    NARCIS (Netherlands)

    Smit, J.

    2005-01-01

    The potter wasp Eumenes coronatus on the move (Hymenoptera: Vespidae) The first record of Eumenus coronatus in the Netherlands dates back from 1954. After that the species was not recorded until 1988. Since then many specimens were collected in the southern part of the country. In 2004 a female was

  11. Effects of Apis mellifera adansonii, L. 1758 (Apidae: Hymenoptera ...

    African Journals Online (AJOL)

    Effects of Apis mellifera adansonii, L. 1758 (Apidae: Hymenoptera) pollination on yields of Cucumeropsis mannii (Naudin) in Kisangani, Democratic Republic of Congo. Boniface Posho Ndola, Yves Brostaux, Guillaume Le Goff, Marie-Lucie Susini, Eric Haubruge, Frederic Francis, Bach Kim Nguyen ...

  12. Revision of the world species of Xeris Costa (Hymenoptera: Siricidae)

    Science.gov (United States)

    Henri Goulet; Caroline Boudreault; Nathan M. Schiff

    2015-01-01

    Xeris is one of ten extant genera of Siricidae known as as woodwasps or horntails. They are important wood-boring Hymenoptera from the Northern Hemisphere. Adults and larvae of Xeris are often intercepted at ports and are consequently of concern as potential alien invasive species. The genus consists of 16 species with eight in...

  13. In-vitro diagnostics of Hymenoptera venom allergy

    NARCIS (Netherlands)

    Rueff, F.; Vos, B.; Przybilla, B.

    In-vitro diagnostics of Hymenoptera venom allergy Patients with a history of anaphylactic sting reactions require an allergological work-up (history, in-vitro tests, and skin tests) to clarify indications on venom immunotherapy and on the type of venom to be used. To demonstrate a venom

  14. Monocoque structure for the SKITTER three-legged walker

    Science.gov (United States)

    Bansek, Robert N.; Booth, Andrew J.; Daneman, Steven A.; Dresser, James A.; Haney, Todd G.; Johnson, Gregory R.; Lindzen, Eric C.; Montgomery, Robert C.; Warren, Andrew L.

    1988-01-01

    The SKITTER 2 design is a monocoque version of the proposed lunar three-legged walker. By the definition of monocoque, the body and legs are a shell with no internal ribbing or supports added for absorbing stresses. The purpose of the monocoque is to encase the elements used for power transmission, power supply, and control of the motion. The material for the structure is a vinyl ester resin, Derakane 8084. This material is easily formable and locally obtainable. The body consists of a hexagonally shaped cylinder with truncated hexagonal pyramids on the top and botton. The legs are eight inch diameter cylinders. The legs are comprised of a tibia section and a femur section. The SKITTER 2 is powered by six actuators which provide linear forces that are transformed into rotary torques by a series of chains and sprockets. The joints connect the femur to the body and the tibia to the femur. Surrounding the joints are flexible rubber hoses that fully encase the chains and sprockets. The SKITTER 2 is capable of walking upside down, righting itself after being overturned, and has the ability to perform in many environments. Applications for this walker include lunar transport or drilling, undersea exploration, and operation in severe surroundings such as arctic temperatures or high radiation.

  15. SYMMETRY AS CONCEPTUAL METAPHOR IN WALKER'S THE COLOR PURPLE

    Directory of Open Access Journals (Sweden)

    Elena Tapia

    2003-05-01

    Full Text Available The author analyzes three types of the conceptual metaphor of embodied symmetry in Alice Walker's novel, The color purple (1982. These metaphorical projections, perceived as equilibrium and its breakage in abstract phenomena, enable readers to reexamine issues of race, non-traditional families, and gender roles. The dis/equilibrium emerges in the novel's epistolary structure. Biological equilibrium breaks in incidents of rape and incest. Walker creates characters in the novel through default-concept opposites of black/white, submissive/dominant, male/female and others. These contraries foreground issues of race and gender. The novel's asymmetries engage readers, leading them to rethink individual character histories and motives. The removal of objects (e.g., rape, mothers deprived of children suggests conceptual asymmetry and alerts readers to parallel themes of sexual and racial oppression. Subjugation sometimes subtle, sometimes blatant- manifests in simple oppositions. In epistemological terms, readers seek causal explanations for the asymmetries of the narrative, interpreting each to recover its history.

  16. Fuzzy Random Walkers with Second Order Bounds: An Asymmetric Analysis

    Directory of Open Access Journals (Sweden)

    Georgios Drakopoulos

    2017-03-01

    Full Text Available Edge-fuzzy graphs constitute an essential modeling paradigm across a broad spectrum of domains ranging from artificial intelligence to computational neuroscience and social network analysis. Under this model, fundamental graph properties such as edge length and graph diameter become stochastic and as such they are consequently expressed in probabilistic terms. Thus, algorithms for fuzzy graph analysis must rely on non-deterministic design principles. One such principle is Random Walker, which is based on a virtual entity and selects either edges or, like in this case, vertices of a fuzzy graph to visit. This allows the estimation of global graph properties through a long sequence of local decisions, making it a viable strategy candidate for graph processing software relying on native graph databases such as Neo4j. As a concrete example, Chebyshev Walktrap, a heuristic fuzzy community discovery algorithm relying on second order statistics and on the teleportation of the Random Walker, is proposed and its performance, expressed in terms of community coherence and number of vertex visits, is compared to the previously proposed algorithms of Markov Walktrap, Fuzzy Walktrap, and Fuzzy Newman–Girvan. In order to facilitate this comparison, a metric based on the asymmetric metrics of Tversky index and Kullback–Leibler divergence is used.

  17. Ground reaction forces of Olympic and World Championship race walkers.

    Science.gov (United States)

    Hanley, Brian; Bissas, Athanassios

    2016-01-01

    Race walking is an Olympic event where no visible loss of contact should occur and the knee must be straightened until midstance. The purpose of this study was to analyse ground reaction forces of world-class race walkers and associate them with key spatiotemporal variables. Nineteen athletes race walked along an indoor track and made contact with two force plates (1000 Hz) while being filmed using high-speed videography (100 Hz). Race walking speed was correlated with flight time (r = .46, p = .049) and flight distance (r = .69, p = .001). The knee's movement from hyperextension to flexion during late stance meant the vertical push-off force that followed midstance was smaller than the earlier loading peak (p push-off forces (r = .60, p = .011). Lower fluctuations in speed during stance were associated with higher stride frequencies (r = .69, p = .001), and highlighted the importance of avoiding too much braking in early stance. The flattened trajectory and consequential decrease in vertical propulsion might help the race walker avoid visible loss of contact (although non-visible flight times were useful in increasing stride length), while a narrow stride width was important in reducing peak forces in all three directions and could improve movement efficiency.

  18. Quantum centipedes: collective dynamics of interacting quantum walkers

    International Nuclear Information System (INIS)

    Krapivsky, P L; Luck, J M; Mallick, K

    2016-01-01

    We consider the quantum centipede made of N fermionic quantum walkers on the one-dimensional lattice interacting by means of the simplest of all hard-bound constraints: the distance between two consecutive fermions is either one or two lattice spacings. This composite quantum walker spreads ballistically, just as the simple quantum walk. However, because of the interactions between the internal degrees of freedom, the distribution of its center-of-mass velocity displays numerous ballistic fronts in the long-time limit, corresponding to singularities in the empirical velocity distribution. The spectrum of the centipede and the corresponding group velocities are analyzed by direct means for the first few values of N . Some analytical results are obtained for arbitrary N by exploiting an exact mapping of the problem onto a free-fermion system. We thus derive the maximal velocity describing the ballistic spreading of the two extremal fronts of the centipede wavefunction, including its non-trivial value in the large- N limit. (paper)

  19. Dissemination of Walker 256 carcinoma cells to rat skeletal muscle

    International Nuclear Information System (INIS)

    Ueoka, H.; Hayashi, K.; Namba, T.; Grob, D.

    1986-01-01

    After injection of 10 6 Walker 256 carcinoma cells labelled with 125 I-5-iodo-2'-deoxyuridine into the tail vein, peak concentration in skeletal muscle was 46 cells/g at 60 minutes, which was lower than 169202, 1665, 555, 198 and 133 cells/g, respectively, at 30 or 60 minutes in lung, liver, spleen, kidney and heart. Because skeletal muscle constitutes 37.4% of body weight, the total number of tumor cells was 2323 cells, which was much greater than in spleen, kidney and heart with 238, 271, and 85 cells, respectively, and only less than in lung and liver, at 222857 and 11700 cells, respectively. The total number in skeletal muscle became greater than in liver at 4 hours and than in lung at 24 hours. Ten minutes after injection of 7.5 x 10 6 Walker 256 carcinoma cells into the abdominal aorta of rats, a mean of 31 colony-forming cells were recovered from the gastrocnemius, while 106 cells were recovered from the lung after injection into the tail vein. These results indicate that a large number of viable tumor cells can be arrested in skeletal muscle through circulation. The rare remote metastasis of malignancies into skeletal muscle despite constantly circulating tumor cells does not appear to be due to poor dissemination of tumor cells into muscle but due to unhospitable environment of skeletal muscle

  20. FreeWalker: a smart insole for longitudinal gait analysis.

    Science.gov (United States)

    Wang, Baitong; Rajput, Kuldeep Singh; Tam, Wing-Kin; Tung, Anthony K H; Yang, Zhi

    2015-08-01

    Gait analysis is an important diagnostic measure to investigate the pattern of walking. Traditional gait analysis is generally carried out in a gait lab, with equipped force and body tracking sensors, which needs a trained medical professional to interpret the results. This procedure is tedious, expensive, and unreliable and makes it difficult to track the progress across multiple visits. In this paper, we present a smart insole called FreeWalker, which provides quantitative gait analysis outside the confinement of traditional lab, at low- cost. The insole consists of eight pressure sensors and two motion tracking sensors, i.e. 3-axis accelerometer and 3-axis gyroscope. This enables measurement of under-foot pressure distribution and motion sequences in real-time. The insole is enabled with onboard SD card as well as wireless data transmission, which help in continuous gait-cycle analysis. The data is then sent to a gateway, for analysis and interpretation of data, using a user interface where gait features are graphically displayed. We also present validation result of a subject's left foot, who was asked to perform a specific task. Experiment results show that we could achieve a data-sampling rate of over 1 KHz, transmitting data up to a distance of 20 meter and maintain a battery life of around 24 hours. Taking advantage of these features, FreeWalker can be used in various applications, like medical diagnosis, rehabilitation, sports and entertainment.

  1. METALLOPROTEINS DURING DEVELOPMENT OF WALKER-256 CARCINOSARCOMA RESISTANT PHENOTYPE.

    Science.gov (United States)

    Chekhun, V F; Lozovska, Yu V; Burlaka, A P; Ganusevich, I I; Shvets, Yu V; Lukianova, N Yu; Todor, I M; Demash, D V; Pavlova, A A; Naleskina, L A

    2015-01-01

    The study was focused on the detection of changes in serum and tumor metal-containing proteins in animals during development ofdoxorubicin-resistant phenotype in malignant cells after 12 courses of chemotherapy. We found that on every stage of resistance development there was a significant increase in content of ferritin and transferrin proteins (which take part in iron traffick and storage) in Walker-256 carc'inosarcoma tissue. We observed decreased serumferritin levels at the beginning stage of the resistance development and significant elevation of this protein levels in the cases withfully developed resistance phenotype. Transferrin content showed changes opposite to that offerritin. During the development of resistance phenotype the tumor tissue also exhibited increased 'free iron' concentration that putatively correlate with elevation of ROS generation and levels of MMP-2 and MMP-9 active forms. The tumor non-protein thiol content increases gradually as well. The serum of animals with early stages of resistance phenotype development showed high ceruloplasmin activity and its significant reduction after loss of tumor sensitivity to doxorubicin. Therefore, the development of resistance phenotype in Walker-256 carcinosarcoma is accompanied by both the deregulation of metal-containing proteins in serum and tumor tissue and by the changes in activity of antioxidant defense system. Thus, the results of this study allow us to determine the spectrum of metal-containing proteins that are involved in the development of resistant tumor phenotype and that may be targeted for methods for doxorubicin sensitivity correction therapy.

  2. Metalloproteins during development of Walker-256 carcinosarcoma resistant phenotype

    Directory of Open Access Journals (Sweden)

    V. F. Chekhun

    2015-04-01

    Full Text Available The study was focused on the detection of changes in serum and tumor metal-containing proteins in animals during development of doxorubicin-resistant phenotype in malignant cells after 12 courses of chemotherapy. We found that on every stage of resistance development there was a significant increase in content of ferritin and transferrin proteins (which take part in iron traffick and storage in Walker-256 carcinosarcoma tissue. We observed decreased serum ferritin levels at the beginning stage of the resistance development and significant elevation of this protein levels in the cases with fully developed resistance phenotype. Transferrin content showed changes opposite to that of ferritin. During the development of resistance phenotype the tumor tissue also exhibited increased ‘free iron’ concentration that putatively correlate with elevation of ROS generation and levels of MMP-2 and MMP-9 active forms. The tumor non-protein thiol content increases gradually as well. The serum of animals with early stages of resistance phenotype development showed high ceruloplasmin activity and its significant reduction after loss of tumor sensitivity to doxorubicin. Therefore, the development of resistance phenotype in Walker-256 carcinosarcoma is accompanied by both the deregulation of metal-containing proteins in serum and tumor tissue and by the changes in activity of antioxidant defense system. Thus, the results of this study allow us to determine the spectrum of metal-containing proteins that are involved in the development of resistant tumor phenotype and that may be targeted for methods for doxorubicin sensitivity correction therapy.

  3. Lightweight Biometric Sensing for Walker Classification Using Narrowband RF Links

    Directory of Open Access Journals (Sweden)

    Tong Liu

    2017-12-01

    Full Text Available This article proposes a lightweight biometric sensing system using ubiquitous narrowband radio frequency (RF links for path-dependent walker classification. The fluctuated received signal strength (RSS sequence generated by human motion is used for feature representation. To capture the most discriminative characteristics of individuals, a three-layer RF sensing network is organized for building multiple sampling links at the most common heights of upper limbs, thighs, and lower legs. The optimal parameters of sensing configuration, such as the height of link location and number of fused links, are investigated to improve sensory data distinctions among subjects, and the experimental results suggest that the synergistic sensing by using multiple links can contribute a better performance. This is the new consideration of using RF links in building a biometric sensing system. In addition, two types of classification methods involving vector quantization (VQ and hidden Markov models (HMMs are developed and compared for closed-set walker recognition and verification. Experimental studies in indoor line-of-sight (LOS and non-line-of-sight (NLOS scenarios are conducted to validate the proposed method.

  4. A 'water walkers' exercise program for the elderly.

    Science.gov (United States)

    Heyneman, C A; Premo, D E

    1992-01-01

    Recent studies have shown that older people, stereotyped as weak, frail, and inactive, demonstrate an equal capacity to reap the physical and psychological benefits of recreational exercise. A low cost aquatic exercise program is proposed that is geared towards those persons who, because of their physical limitations, are unable to participate in the more traditional walking or low-impact aerobics programs currently available for seniors. A water-based program would allow these people to gain all the advantages of land-based exercise with out stress or strain on arthritic joints. In addition, the use of water walkers (a buoyancy device which attaches easily around the waist) would allow total freedom of movement without fear of deep water. Those with various levels of disability could, therefore, participate at their own pace. Two programs, including transportation, would be provided twice a week for 8 weeks each. An individual 45-minute session would consist of a warm-up period with gentle stretching, a cardiovascular segment, a cool-down period, strength-training, and a final stretching time. All exercises would be conducted with participants wearing the water walkers, allowing total immersion to the shoulder. Free to move about the pool, they would be encouraged to interact socially with one another. The results of the program would be determined by measuring range of motion, cardiovascular endurance, and strength before and after each 8-week session. Participants' level of self confidence and life satisfaction will be estimated and any psychological improvement will be documented.

  5. Third annual Walker Branch watershed research symposium: Programs and abstracts

    International Nuclear Information System (INIS)

    1992-03-01

    The methods and concepts of watershed research, originally applied in an experimental or monitoring mode to relatively small catchments, are increasingly being used at larger scales and for specific applied problems. Research at Oak Ridge National Laboratory, the Tennessee Valley Authority, the US Forest Service, and other agencies and institutions participating in this symposium reflects research over a broad range of spatial scales. These research projects address the basic atmospheric, geophysical, biogeochemical, and biological processes that regulate the responses of forested ecosystems to natural environmental variation and anthropogenic stresses. Regional and global issues addressed by presentations include emissions of carbon dioxide, methane, and other hydrocarbons; deposition of sulfate, nitrate, and mercury; land-use changes; biological diversity; droughts; and water quality. The Department of Energy's local research site, Walker Branch Watershed, is a long-term ecosystem research project initiated on the Oak Ridge Reservation in 1967. Walker Branch provides a well-characterized site where many of these methods can be tested and applied.In addition, other large-scale experiments represented in this symposium include experiments on the effects of clearcutting and burning on forest structure and productivity associated with Coweeta Hydrologic Laboratory, and whole-tree ozone exposure chambers constructed by TVA and ORNL researchers

  6. Lightweight Biometric Sensing for Walker Classification Using Narrowband RF Links.

    Science.gov (United States)

    Liu, Tong; Liang, Zhuo-Qian

    2017-12-05

    This article proposes a lightweight biometric sensing system using ubiquitous narrowband radio frequency (RF) links for path-dependent walker classification. The fluctuated received signal strength (RSS) sequence generated by human motion is used for feature representation. To capture the most discriminative characteristics of individuals, a three-layer RF sensing network is organized for building multiple sampling links at the most common heights of upper limbs, thighs, and lower legs. The optimal parameters of sensing configuration, such as the height of link location and number of fused links, are investigated to improve sensory data distinctions among subjects, and the experimental results suggest that the synergistic sensing by using multiple links can contribute a better performance. This is the new consideration of using RF links in building a biometric sensing system. In addition, two types of classification methods involving vector quantization (VQ) and hidden Markov models (HMMs) are developed and compared for closed-set walker recognition and verification. Experimental studies in indoor line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios are conducted to validate the proposed method.

  7. Lightweight Biometric Sensing for Walker Classification Using Narrowband RF Links

    Science.gov (United States)

    Liang, Zhuo-qian

    2017-01-01

    This article proposes a lightweight biometric sensing system using ubiquitous narrowband radio frequency (RF) links for path-dependent walker classification. The fluctuated received signal strength (RSS) sequence generated by human motion is used for feature representation. To capture the most discriminative characteristics of individuals, a three-layer RF sensing network is organized for building multiple sampling links at the most common heights of upper limbs, thighs, and lower legs. The optimal parameters of sensing configuration, such as the height of link location and number of fused links, are investigated to improve sensory data distinctions among subjects, and the experimental results suggest that the synergistic sensing by using multiple links can contribute a better performance. This is the new consideration of using RF links in building a biometric sensing system. In addition, two types of classification methods involving vector quantization (VQ) and hidden Markov models (HMMs) are developed and compared for closed-set walker recognition and verification. Experimental studies in indoor line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios are conducted to validate the proposed method. PMID:29206188

  8. Vertical force and wrist deviation angle when using a walker to stand up and sit down.

    Science.gov (United States)

    Leung, Cherng-Yee; Yeh, Po-Chan

    2011-08-01

    Research investigating walkers suggests that safety and assistance for the elderly with weak lower limbs were important. However, the relationship between the use of a walker and the upper limbs has received little investigation. Standing up and sitting down are important daily activities. Therefore, the aim of this study was to explore wrist deviation and vertical force among elderly individuals using a walker for assistance to stand up and sit down. In total, 64 elderly volunteers (M age = 80.22, SD = 9.36) were enrolled. Data were obtained from four load cells and a twin-axis wrist goniometer. Wrist deviation and vertical force were examined when participants used a walker with horizontal handles to assist in standing up and sitting down. Significant wrist angle deviation occurred with the use of a walker, with dorsiflexion of the right hand greater than that of the left. Males exerted significantly greater vertical force. In the sitting position, greater ulnar deviation was seen among experienced walker users, whereas during standing, experienced users exhibited greater dorsiflexion. The horizontal handles of most marketed walkers may cause user wrist deviations, suggesting researchers should pursue improvements in walker design.

  9. Where Are They Now: Nathalie Walker Moves from Science to Activism and Art Communications | Poster

    Science.gov (United States)

    Whether it’s in a flowerbed or an art gallery, former Werner H. Kirsten (WHK) student intern Nathalie Walker can’t help but to cause a buzz. Since completing her WHK internship in the summer of 2015, Walker has been attending Loyola University Maryland, where she is striving to make a positive impact on campus.

  10. Robertson-Walker solutions for various types of energy-momentum tensor

    International Nuclear Information System (INIS)

    Lukacs, B.

    1976-01-01

    Robertson-Walker solutions are important in general relativity as universe solutions. This paper contains a number of Robertson-Walker-type solutions for certain cases, namely, for noncharged massless scalar meson fields, viscous fluids, Hookean elastic mediums, and Kelvin-Voigt viscoelastic systems. (author)

  11. 75 FR 24753 - The Walker Auto Group, Inc., Miamisburg, OH; Notice of Negative Determination Regarding...

    Science.gov (United States)

    2010-05-05

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-72,471] The Walker Auto Group... Auto Group, Inc., Miamisburg, Ohio, was based on the finding that the subject firm did not shift abroad... of the subject firm should be eligible for TAA because the Walker Auto Group, Inc., Miamisburg, Ohio...

  12. 78 FR 37706 - Safety Standards for Infant Walkers and Infant Swings

    Science.gov (United States)

    2013-06-24

    ... test procedure that is needed for testing certain style walkers; Two references to federal regulations... a new step to the test procedure that enables test laboratories to test certain styles of walkers... direct final rule. Although the Administrative Procedure Act (APA) generally requires notice and comment...

  13. Maximum distance between the Leader and the Laggard for three Brownian walkers

    International Nuclear Information System (INIS)

    Majumdar, Satya N; Bray, Alan J

    2010-01-01

    We consider three independent Brownian walkers moving on a line. The process terminates when the leftmost walker (the 'Leader') meets either of the other two walkers. For arbitrary values of the diffusion constants D 1 (the Leader), D 2 and D 3 of the three walkers, we compute the probability distribution P(m|y 2 , y 3 ) of the maximum distance m between the Leader and the current rightmost particle (the 'Laggard') during the process, where y 2 and y 3 are the initial distances between the Leader and the other two walkers. The result has, for large m, the form P(m|y 2 , y 3 ) ∼ A(y 2 , y 3 )m −δ , where δ = (2π − θ)/(π − θ) and θ= cos -1 (D 1 /√((D 1 +D 2 )(D 1 +D 3 ))). The amplitude A(y 2 , y 3 ) is also determined exactly

  14. Development and evaluation of low-cost walker with trunk support for senior citizen.

    Science.gov (United States)

    Poier, Paloma Hohmann; Godke, Francisco; Foggiatto, José Aguiomar; Ulbricht, Leandra

    2017-10-09

    Develop and evaluate a low-cost walker with trunk support for senior citizens. Two-stage descriptive study: development of a walker with trunk support and evaluation with fourth age senior citizens. Twenty-three fourth age senior citizens were selected. The evaluated criteria were the immediate influence of the walker on the static stabilometry with baropodometer and the evaluation of gait with accelerometers monitoring time and amplitude of the hip movement. There was a significant decrease in the body oscillation of senior citizens with the use of the developed walker, and there were changes in the joint amplitudes of the hip, but they were not significant. Using low-cost materials, it was possible to develop and equipment that met resistance and effectiveness requirements. The walker interfered in the balance of the senior citizens, reducing significantly the static body oscillation.

  15. 76 FR 13665 - Arcelor Mittal, Formerly Known as Mittal Steel Walker Wire, a Subsidiary of Arcelor Mittal...

    Science.gov (United States)

    2011-03-14

    ... Known as Mittal Steel Walker Wire, a Subsidiary of Arcelor Mittal--Montreal, Including On-Site Leased... Steel Walker Wire, a subsidiary of Arcelor Mittal-- Montreal, including on-site leased workers from... Walker Wire, Inc., Ferndale, Michigan, separated from employment on or after July 23, 2006 through August...

  16. Brachymeria pandora (Crawford (Hymenoptera, Chalcididae: a new parasitoid of Historis odius (Fabricius (Lepidoptera, Nymphalidae

    Directory of Open Access Journals (Sweden)

    Hélcio R. Gil-Santana

    2005-12-01

    Full Text Available The first record of parasitism of Brachymeria pandora (Crawford, 1914 (Hymenoptera, Chalcididae on Historis odius (Fabricius, 1775 (Lepidoptera, Nymphalidae in the State of Rio de Janeiro, Brazil is presented.Apresenta-se o primeiro registro de parasitismo de Brachymeria pandora (Crawford, 1914 (Hymenoptera, Chalcididae em Historis odius (Fabricius, 1775 (Lepidoptera, Nymphalidae, no estado do Rio de Janeiro, Brasil.

  17. KEANEKARAGAMAN HYMENOPTERA PARASITIKA PADA TIPE EKOSISTEM BERBEDA DI BANGKA TENGAH, KEPULAUAN BANGKA BELITUNG

    Directory of Open Access Journals (Sweden)

    Herry Marta Saputra

    2017-05-01

    Full Text Available Diversity of parasitic Hymenoptera in different ecosystem types in Central Bangka, Bangka-Belitung Islands. Hymenoptera richness is dominated by parasitic species. More than 80% of Hymenoptera play a role as parasitoid on arthropods that are mostly insects. Diversity of parasitic Hymenoptera is widely studied in various types of terrestrial ecosystems including agro-ecosystem and non-agro-ecosystem. This study aimed to invent and compare the diversity of parasitic Hymenoptera in three different ecosystems, i.e., forest, oil palm plantation, and ex-tin mining. The location was located in Central Bangka Regency, Bangka Island. The study was conducted in Juli 2014 until October 2015. Parasitic Hymenoptera was collected with insect sweep net and yellow pan trap on one transect line with 1000 m length. Parasitic Hymenoptera were found on forest as much as 732 morphospecies, 326 morphospecies on oil palm plantations, and 293 morphospecies on ex-tin mining. Diversity and abundance of parasitic Hymenoptera on forest was higher than oil palm plantation and ex-tin mining area. Braconidae family was found dominant on forest, however on oil palm plantation and extin mining area the dominant family was Scelionidae.

  18. Four newly recorded species of the genus Meteorus Haliday (Hymenoptera: Braconidae: Euphorinae) from Korea

    OpenAIRE

    Hye-Rin Lee; Tae-Ho An; Deok-Seo Ku; Bong-Kyu Byun

    2017-01-01

    Four species of the genus Meteorus (Hymenoptera: Braconidae: Euphorinae) are reported for the first time from Korea: Meteorus brevicauda Thomson, 1895, Meteorus colon Haliday, 1835, Meteorus kunashiricus Belokobylskij, 1995, and Meteorus vexator Haliday, 1835. Diagnosis, distribution, and host information are provided for each species. Keywords: Braconidae, Hymenoptera, Korea, Meteorus, New record

  19. Four newly recorded species of the genus Meteorus Haliday (Hymenoptera: Braconidae: Euphorinae from Korea

    Directory of Open Access Journals (Sweden)

    Hye-Rin Lee

    2017-12-01

    Full Text Available Four species of the genus Meteorus (Hymenoptera: Braconidae: Euphorinae are reported for the first time from Korea: Meteorus brevicauda Thomson, 1895, Meteorus colon Haliday, 1835, Meteorus kunashiricus Belokobylskij, 1995, and Meteorus vexator Haliday, 1835. Diagnosis, distribution, and host information are provided for each species. Keywords: Braconidae, Hymenoptera, Korea, Meteorus, New record

  20. Conformal Killing vectors in Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Maartens, R.; Maharaj, S.d.

    1986-01-01

    It is well known that Robertson-Walker spacetimes admit a conformal Killingl vector normal to the spacelike homogeneous hypersurfaces. Because these spacetimes are conformally flat, there are a further eight conformal Killing vectors, which are neither normal nor tangent to the homogeneous hypersurfaces. The authors find these further conformal Killing vectors and the Lie algebra of the full G 15 of conformal motions. Conditions on the metric scale factor are determined which reduce some of the conformal Killing vectors to homothetic Killing vectors or Killing vectors, allowing one to regain in a unified way the known special geometries. The non-normal conformal Killing vectors provide a counter-example to show that conformal motions do not, in general, map a fluid flow conformally. These non-normal vectors are also used to find the general solution of the null geodesic equation and photon Liouville equation. (author)

  1. Multiple phases and vicious walkers in a wedge

    Directory of Open Access Journals (Sweden)

    Gesualdo Delfino

    2015-12-01

    Full Text Available We consider a statistical system in a planar wedge, for values of the bulk parameters corresponding to a first order phase transition and with boundary conditions inducing phase separation. Our previous exact field theoretical solution for the case of a single interface is extended to a class of systems, including the Blume–Capel model as the simplest representative, allowing for the appearance of an intermediate layer of a third phase. We show that the interfaces separating the different phases behave as trajectories of vicious walkers, and determine their passage probabilities. We also show how the theory leads to a remarkable form of wedge covariance, i.e. a relation between properties in the wedge and in the half plane, which involves the appearance of self-Fourier functions.

  2. Inverse curvature flows in asymptotically Robertson Walker spaces

    Science.gov (United States)

    Kröner, Heiko

    2018-04-01

    In this paper we consider inverse curvature flows in a Lorentzian manifold N which is the topological product of the real numbers with a closed Riemannian manifold and equipped with a Lorentzian metric having a future singularity so that N is asymptotically Robertson Walker. The flow speeds are future directed and given by 1 / F where F is a homogeneous degree one curvature function of class (K*) of the principal curvatures, i.e. the n-th root of the Gauss curvature. We prove longtime existence of these flows and that the flow hypersurfaces converge to smooth functions when they are rescaled with a proper factor which results from the asymptotics of the metric.

  3. Field diet of the grasshopper Abracris dilecta Walker (Orthoptera, Acrididae

    Directory of Open Access Journals (Sweden)

    Carlos Frankl Sperber

    1996-01-01

    Full Text Available Abracris dilecta Walker, 1870 (Orthoptera, Acrididae, Ommatolampinae ate leafs of at least 14 plant species, in the families Asteraceae, Lamiaceae, Malvales (Sterculiaceae, Tiliaceae or Malvaceae, Poaceae, Fabaceae, Verbenaceae, Aristolochiaceae, Rubiaceae and Melastomataccae. Elephantopus mollis H.B.K. (Asteraceae and Hyptis suaveolens Poit. (Lamiaceae comprised 50% of the diet. The diet breadth of A. dilecta was compared to that of other 11 grasshopper species of the same sub-family, with rarefaction curves. The number of plant species eaten by A. dilecta was greater than that of nine other grasshopper species of the same sub-family (Rhachicreagra spp. but was lower then two others (Microptylopteryx hebardi Rehn, 1905 and Rhachicreagra astytophallus Jago & Rowell, 1981. This results are discussed in view of the broad geographical range and possession of developed wings by A. dilecta, which contrasts with most Ommatolampinae grasshoppers.

  4. A combined approach to heat stress effect on male fertility in Nasonia vitripennis: from the physiological consequences on spermatogenesis to the reproductive adjustment of females mated with stressed males.

    Directory of Open Access Journals (Sweden)

    Marlène Chirault

    Full Text Available In recent years, several studies have shown a decline in reproductive success in males in both humans and wildlife. Research on male fertility has largely focused on vertebrates, although invertebrates constitute the vast majority of terrestrial biodiversity. The reduction of their reproductive capacities due to environmental stresses can have strong negative ecological impacts, and also dramatic consequences on world food production if it affects the reproductive success of biological control agents, such as parasitic wasps used to control crop pests. Here Nasonia vitripennis, a parasitic wasp of various fly species, was studied to test the effects of 24h-heat stress applied during the first pupal stage on male fertility. Results showed that only primary spermatocytes were present at the first pupal stage in all cysts of the testes. Heat stress caused a delay in spermatogenesis during development and a significant decrease in sperm stock at emergence. Females mated with these heat-stressed males showed a reduce sperm count stored in their spermatheca. Females did not appear to distinguish heat-stressed from control males and did not remate more frequently to compensate for the lack of sperm transferred. As a result, females mated with heat-stressed males produced a suboptimal lifetime offspring sex ratio compared to those mated with control males. This could further impact the population dynamics of this species. N. vitripennis appears to be an interesting biological model to study the mechanisms of subfertility and its consequence on female reproductive strategies and provides new research perspectives in both invertebrates and vertebrates.

  5. A combined approach to heat stress effect on male fertility in Nasonia vitripennis: from the physiological consequences on spermatogenesis to the reproductive adjustment of females mated with stressed males.

    Science.gov (United States)

    Chirault, Marlène; Lucas, Christophe; Goubault, Marlène; Chevrier, Claude; Bressac, Christophe; Lécureuil, Charlotte

    2015-01-01

    In recent years, several studies have shown a decline in reproductive success in males in both humans and wildlife. Research on male fertility has largely focused on vertebrates, although invertebrates constitute the vast majority of terrestrial biodiversity. The reduction of their reproductive capacities due to environmental stresses can have strong negative ecological impacts, and also dramatic consequences on world food production if it affects the reproductive success of biological control agents, such as parasitic wasps used to control crop pests. Here Nasonia vitripennis, a parasitic wasp of various fly species, was studied to test the effects of 24h-heat stress applied during the first pupal stage on male fertility. Results showed that only primary spermatocytes were present at the first pupal stage in all cysts of the testes. Heat stress caused a delay in spermatogenesis during development and a significant decrease in sperm stock at emergence. Females mated with these heat-stressed males showed a reduce sperm count stored in their spermatheca. Females did not appear to distinguish heat-stressed from control males and did not remate more frequently to compensate for the lack of sperm transferred. As a result, females mated with heat-stressed males produced a suboptimal lifetime offspring sex ratio compared to those mated with control males. This could further impact the population dynamics of this species. N. vitripennis appears to be an interesting biological model to study the mechanisms of subfertility and its consequence on female reproductive strategies and provides new research perspectives in both invertebrates and vertebrates.

  6. Designing instrumented walker to measure upper-extremity's efforts: A case study.

    Science.gov (United States)

    Khodadadi, Mohammad; Baniasad, Mina Arab; Arazpour, Mokhtar; Farahmand, Farzam; Zohoor, Hassan

    2018-02-26

    The high prevalence of shoulder pain in using walkers in patients who have spinal cord injury (SCI). Also, the limited options available to economically measure grip forces in walkers, which drove the need to create one. This article describes a method to obtain upper-extremities' forces and moments in a person with SCI by designing an appropriate instrumented walker. First, since the commercial multidirectional loadcells are too expensive, custom loadcells are fabricated. Ultimately, a complete gait analysis by means of VICON motion analysis and using inverse dynamic method has been held to measure upper-extremities' efforts. The results for a person with SCI using a two-wheel walker in low and high heights and a basic walker show that there are higher shoulder and elbow flexion-extension moments and also higher shoulder forces in superior-inferior direction and higher elbow and wrist forces in anterior-posterior directions. The results are not much different in using two different types of walker. By using the proposed method, upper-extremities' forces and moments were obtained and the results were compared to each other in using two different walkers.

  7. Effects of aging on identifying emotions conveyed by point-light walkers.

    Science.gov (United States)

    Spencer, Justine M Y; Sekuler, Allison B; Bennett, Patrick J; Giese, Martin A; Pilz, Karin S

    2016-02-01

    The visual system is able to recognize human motion simply from point lights attached to the major joints of an actor. Moreover, it has been shown that younger adults are able to recognize emotions from such dynamic point-light displays. Previous research has suggested that the ability to perceive emotional stimuli changes with age. For example, it has been shown that older adults are impaired in recognizing emotional expressions from static faces. In addition, it has been shown that older adults have difficulties perceiving visual motion, which might be helpful to recognize emotions from point-light displays. In the current study, 4 experiments were completed in which older and younger adults were asked to identify 3 emotions (happy, sad, and angry) displayed by 4 types of point-light walkers: upright and inverted normal walkers, which contained both local motion and global form information; upright scrambled walkers, which contained only local motion information; and upright random-position walkers, which contained only global form information. Overall, emotion discrimination accuracy was lower in older participants compared with younger participants, specifically when identifying sad and angry point-light walkers. In addition, observers in both age groups were able to recognize emotions from all types of point-light walkers, suggesting that both older and younger adults are able to recognize emotions from point-light walkers on the basis of local motion or global form. (c) 2016 APA, all rights reserved).

  8. Four-wheeled walker related injuries in older adults in the Netherlands.

    Science.gov (United States)

    van Riel, K M M; Hartholt, K A; Panneman, M J M; Patka, P; van Beeck, E F; van der Cammen, T J M

    2014-02-01

    With ageing populations worldwide, mobility devices are used more than ever. In the current literature there is no consensus whether the available mobility devices safely improve the mobility of their users. Also, evidence is lacking concerning the risks and types of injuries sustained while using a four-wheeled walker. To assess injury risks and injury patterns in older adults (≥65 years) who presented at Emergency Departments (ED) in the Netherlands with an injury due to using a four-wheeled walker. In this study, the Dutch Injury Surveillance System was used to obtain a national representative sample of annual ED visits in the Netherlands in the adult population (≥65 years) sustaining an injury while using a four-wheeled walker. The numbers of four-wheeled walker users in the Netherlands were obtained from the national insurance board. The numbers of ED visits were divided by the numbers of four-wheeled walker users to calculate age- and sex-specific injury risks. Annually 1869 older adults visited an ED after sustaining an injury while using a four-wheeled walker. Falls were the main cause of injury (96%). The injury risk was 3.1 per 100 users of four-wheeled walkers. Women (3.5 per 100 users) had a higher risk than men (2.0 per 100 users). Injury risk was the highest in women aged 85 years and older (6.2 per 100 users). The majority of injuries were fractures (60%) with hip fracture (25%) being the most common injury. Nearly half of all four-wheeled walker related injuries required hospitalisation, mostly due to hip fractures. Healthcare costs per injury were approximately €12 000. This study presents evidence that older adults experiencing a fall while using a four-wheeled walker are at high risk to suffer severe injuries.

  9. Assistive devices alter gait patterns in Parkinson disease: advantages of the four-wheeled walker.

    Science.gov (United States)

    Kegelmeyer, Deb A; Parthasarathy, Sowmya; Kostyk, Sandra K; White, Susan E; Kloos, Anne D

    2013-05-01

    Gait abnormalities are a hallmark of Parkinson's disease (PD) and contribute to fall risk. Therapy and exercise are often encouraged to increase mobility and decrease falls. As disease symptoms progress, assistive devices are often prescribed. There are no guidelines for choosing appropriate ambulatory devices. This unique study systematically examined the impact of a broad range of assistive devices on gait measures during walking in both a straight path and around obstacles in individuals with PD. Quantitative gait measures, including velocity, stride length, percent swing and double support time, and coefficients of variation were assessed in 27 individuals with PD with or without one of six different devices including canes, standard and wheeled walkers (two, four or U-Step). Data were collected using the GAITRite and on a figure-of-eight course. All devices, with the exception of four-wheeled and U-Step walkers significantly decreased gait velocity. The four-wheeled walker resulted in less variability in gait measures and had less impact on spontaneous unassisted gait patterns. The U-Step walker exhibited the highest variability across all parameters followed by the two-wheeled and standard walkers. Higher variability has been correlated with increased falls. Though subjects performed better on a figure-of-eight course using either the four-wheeled or the U-Step walker, the four-wheeled walker resulted in the most consistent improvement in overall gait variables. Laser light use on a U-Step walker did not improve gait measures or safety in figure-of-eight compared to other devices. Of the devices tested, the four-wheeled-walker offered the most consistent advantages for improving mobility and safety. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Vacuum quantum effect for curved boundaries in static Robertson-Walker space-time

    International Nuclear Information System (INIS)

    Setare, M.R.; Sadeghi, J.

    2009-01-01

    The energy-momentum tensor for a massless conformally coupled scalar field in the region between two curved boundaries in k=-1 static Robertson-Walker space-time is investigated. We assume that the scalar field satisfies the Dirichlet boundary condition on the boundaries. k=-1 Robertson-Walker space is conformally related to the Rindler space, as a result we can obtain vacuum expectation values of energy-momentum tensor for conformally invariant field in Robertson-Walker space from the corresponding Rindler counterpart by the conformal transformation.

  11. Allergen-specific immunotherapy of Hymenoptera venom allergy

    DEFF Research Database (Denmark)

    Schiener, Maximilian; Graessel, Anke; Ollert, Markus

    2017-01-01

    Stings of hymenoptera can induce IgE-mediated hypersensitivity reactions in venom-allergic patients, ranging from local up to severe systemic reactions and even fatal anaphylaxis. Allergic patients' quality of life can be mainly improved by altering their immune response to tolerate the venoms...... by injecting increasing venom doses over years. This venom-specific immunotherapy is highly effective and well tolerated. However, component-resolved information about the venoms has increased in the last years. This knowledge is not only able to improve diagnostics as basis for an accurate therapy......, but was additionally used to create tools which enable the analysis of therapeutic venom extracts on a molecular level. Therefore, during the last decade the detailed knowledge of the allergen composition of hymenoptera venoms has substantially improved diagnosis and therapy of venom allergy. This review focuses...

  12. Natural enemies of corn silk flies: Euxesta Stigmatias (Loew, Chaetopsis Massyla (Walker and Eumecosommyia Nubila (Wiedemann in Guasave Sinaloa, México

    Directory of Open Access Journals (Sweden)

    Jesús Ricardo Camacho Báez

    2012-09-01

    Full Text Available The flies species complex of corn, known as “stigma flies”, including the corn-silk fly, Euxesta stigmatias (Loew,Chaetopsis massyla (Walker and Eumecosommyia nubila (Wiedemann, they have became an important pest problem in the state of Sinaloa. The damage is associated with decaying symptoms has severely affected the quality and yield of the crop. The objectives of this research project are to report sampling results on the presence of natural sources of biological control agents (parasitoids, predators, and entomopathogenic nematodes with biological control potential capacity to manage the populations of this flies species complex. This research was conducted during the spring-summer growingseason of 2011. Samples where collected for eight continuous weeks during the corn cob development and maturation. The sampled corn variety was the hybrid Asgrow Garañon. We collected predominat two wasp species belonging to the order Hymenoptera, families Pteromalidae and Eurytomidae, which are parasites to the pupa stage of corn silk fly. In addition, a wasp from the genus Spalangia spp. The latter has shown a stronger natural parasitic effect of 47% on Euxesta stigmatias (Loew. We also observed a population of the pirate bug Orius insidiosus (Say during the months of March-July, attacking several developmental stages of the fly. Soil samples where also processed to isolate and to identify populations of possible entomopathogenic nematodes (EPN. Larvae of Galleria melonella L. where utilized as nematode traps. Populations of nematodes from three different sites where isolated from CIIDIR-IPN Unidad Sinaloa, Guasave and Maximiliano R. Lopez, all located in the Guasave. The isolated populations are included in the Rhabditidae family, genus and specie identification is still in progress. The natural enemies found have shown potential capacity to asseses them asbiological control agents on the corn flies complex.

  13. História natural da interação entre Meteorus sp. Haliday, 1835 (Hymenoptera: Braconidae) e seu hiperparasitoide Toxeumella albipes Girault, 1913 (Hymenoptera: Pteromalidae)

    OpenAIRE

    Sobczak, JF; Maia, DP; Moura, JCMS; Costa, VA; Vasconcellos-Neto, J

    2012-01-01

    Some parasitoids build a cocoon mass that hangs in the host body until the adults emergence, which is an advantage against attack by predators who troll the vegetation in search of prey. However, such behaviour is not effective against the hyperparasitoid attacks. This study reports the interaction between the caterpillar Manduca sexta Linnaeus, 1763 (Lepidoptera, Sphingidae) parasitised by Meteorus sp. (Hymenoptera, Braconidae) larvae and its hyperparasitoid Toxeumella albipes (Hymenoptera, ...

  14. On the identity of Melipona torrida Friese (Hymenoptera, Apidae)

    OpenAIRE

    Melo, Gabriel A. R.

    2013-01-01

    On the identity of Melipona torrida Friese (Hymenoptera, Apidae). Melipona marginata var. torrida Friese, 1916, described from three workers putatively collected in Costa Rica, never had its identity properly recognized. Since its original description, no additional specimens have ever been collected in Costa Rica. It is argued here that Melipona torrida was based on mislabeled specimens and corresponds to Melipona marginata obscurior Moure, 1971, a form known only from southern Brazil, Argen...

  15. Spermatogenesis in the parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae)

    Czech Academy of Sciences Publication Activity Database

    Carabajal Paladino, Leonela Z.; Lo Nostro, F.; Papeschi, A.; Cladera, J.; Bressa, M. J.

    2017-01-01

    Roč. 98, č. 1 (2017), s. 38-43 ISSN 0001-7272 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Hymenoptera * modified meiosis * abortive division Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 1.211, year: 2016 http://onlinelibrary.wiley.com/doi/10.1111/azo.12148/pdf

  16. Cross-reacting carbohydrate determinants and hymenoptera venom allergy.

    Science.gov (United States)

    Brehler, Randolf; Grundmann, Sonja; Stöcker, Benedikt

    2013-08-01

    Insect venom allergy is an important cause of anaphylaxis. Venom immunotherapy assume the clear identification of the culprit insect, but this is impeded by Immunoglobulin E (IgE) antibodies to cross reactive carbohydrate determinant (CCD) epitopes of common glycoproteins. Here we give an overview about inducers, importance, and relevance of anti-N-Glycan CCD IgE antibodies. Pollen exposure and insect stings induce anti-CCD IgE antibodies interfering with in-vitro tests for allergy diagnosis due to extensive IgE cross-reactivity. Instead of being biologically active these antibodies are irrelevant for allergic reactions due to hymenoptera stings. The general response of the immune system to the ubiquitous exposure to N-glycan containing glycoproteins is still a matter of debate. CCD specific IgG antibodies in sera of bee keepers suggest tolerance induction due to high-dose exposure. Tolerance induction by pollen and food glycoproteins has not been proved. Hymenoptera stings and pollen exposure induce anti-CCD IgE. In regard to anaphylaxis due to Hymenoptera stings these antibodies are not clinically relevant, but they are important for the specificity of in-vitro tests proving insect venom allergy. The introduction of component based diagnostic IgE testing improves the specificity of in-vitro tests if proteins devoid of CCD epitopes are used.

  17. Draft Title V Operating Permit: Andeavor Field Services, LLC - Walker Hollow Compressor Station

    Science.gov (United States)

    Draft Title V Operating Permit, statement of basis, public notice bulletin, and the administrative permit docket (application and other supporting documents) for the Draft Part 71 Permit for Andeavor Field Services, LLC - Walker Hollow CS.

  18. The captain class : the hidden force that creates the world's greatest teams / Sam Walker

    Trove (Australia)

    Walker, Sam

    2017-01-01

    ... it is. It's not the coach. It's not the star. It's not chemistry. It's not a strategy. It's something else entirely. Several years ago, Sam Walker set out to answer one of the most hotly debated questions in sports ...

  19. On the minimal vacuum definition for spin 1 massive fields in Robertson-Walker universes

    International Nuclear Information System (INIS)

    Castagnino, M.; Laciana, C.; Chimento, L.

    1986-01-01

    A definition of quantum vacuum is introduced for spin 1, massive, neutral fields, in spatially flat Robertson-Walker universes. For this definition all relevant observables turn out to be devoid of ultraviolet divergencies. (author)

  20. Draft Title V Operating Permit: Andeavor Field Services, LLC - Walker Hollow Compressor Station

    Science.gov (United States)

    Draft Operating Permit (Permit Number: V-UO-000979-2017.00), statement of basis, public notice bulletin, and the administrative permit docket (application and other supporting documents) for the Andeavor Walker Hollow Compressor Station.

  1. Spacetime emergence of the robertson-walker universe from a matrix model.

    Science.gov (United States)

    Erdmenger, Johanna; Meyer, René; Park, Jeong-Hyuck

    2007-06-29

    Using a novel, string theory-inspired formalism based on a Hamiltonian constraint, we obtain a conformal mechanical system for the spatially flat four-dimensional Robertson-Walker Universe. Depending on parameter choices, this system describes either a relativistic particle in the Robertson-Walker background or metric fluctuations of the Robertson-Walker geometry. Moreover, we derive a tree-level M theory matrix model in this time-dependent background. Imposing the Hamiltonian constraint forces the spacetime geometry to be fuzzy near the big bang, while the classical Robertson-Walker geometry emerges as the Universe expands. From our approach, we also derive the temperature of the Universe interpolating between the radiation and matter dominated eras.

  2. Walking my way? Walker gender and display format Confounds the perception of specific emotions.

    Science.gov (United States)

    Halovic, Shaun; Kroos, Christian

    2018-02-01

    Previous evidence has shown that males and females display different gait kinematics which may influence the perception of emotions displayed through the same walking gait. We therefore investigated the influence of walker gender on the perception of happiness, sadness, anger and fear displayed through walking movements. Full-light (FL), point-light (PL) and synthetically modelled point-light walkers (SW) of both genders were shown to perceivers over three experiments. Additionally, gender ambiguous synthetic walkers were shown to control for the influence of form, gender stereotypes and idiosyncratic gait movements on emotional gait perception. Each emotion was identified above chance level for both walker genders and in all display conditions though significantly less in PL and SW than in FL. The gender of the walker did not influence the pattern of identifications in FL walkers (Fear > Sad > Happy > Anger > Neutral), but did influence the identification patterns in PL (Female: [Happy = Sad = Fear = Anger] > Neutral; Male: Fear = Sad = [Happy > Anger] > Neutral) and SWs (Female: Happy = Sad = Anger = Fear = Neutral; Male: [Happy = Sad = Anger] > [Fear = Neutral]; Ambiguous: [[Happy = Sad = Anger] > Fear] = Neutral). The gender of the walker and format in which they are displayed influenced the perception of different basic emotions. The constructed SW stimuli also displayed happiness, sadness and anger with equivalent intensity in female, male and gender ambiguous walkers thus untangling the perception-expression entanglement that has plagued previous emotion perception research. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  3. Usher syndrome associated with a variant of Dandy-Walker malformation.

    Science.gov (United States)

    Simsek, Tulay; Ozdamar, Yasemin; Simsek, Enver; Men, Gamze

    2010-05-21

    Three cases of Usher syndrome associated with a variant of Dandy-Walker malformation in three siblings from consanguineous Turkish parents are described. The siblings had retinitis pigmentosa and hearing loss. Two of the siblings also had mental retardation, which is not a constant finding in Usher syndrome. Dandy-Walker malformation might have contributed to the mental retardation in two of these patients and might be a coincidental finding with Usher syndrome. Copyright 2010, SLACK Incorporated.

  4. MECHANICAL EFFICIENCY OF A CHAMPION WALKER* • • • • .o •

    African Journals Online (AJOL)

    Oxygen consumplions were measured on a champion walker, while walking at between 6·4 and 16·9 km / hand while running at between lJ·] and 17-7 km/h. Above. 9-7 km / h the curve of oxygen consumption against speed for walking was almost twice as steep as that for rlInning, indicating that el'en champion walkers are ...

  5. [Upper extremity kinetics and energy expenditure during walker-assisted gait in children with cerebral palsy].

    Science.gov (United States)

    Konop, Katherine A; Strifling, Kelly M B; Wang, Mei; Cao, Kevin; Eastwood, Daniel; Jackson, Scott; Ackman, Jeffrey; Altiok, Haluk; Schwab, Jeffrey; Harris, Gerald F

    2009-01-01

    We evaluated the relationships between upper extremity (UE) kinetics and the energy expenditure index during anterior and posterior walker-assisted gait in children with spastic diplegic cerebral palsy (CP). Ten children (3 boys, 7 girls; mean age 12.1 years; range 8 to 18 years) with spastic diplegic CP, who ambulated with a walker underwent gait analyses that included UE kinematics and kinetics. Upper extremity kinetics were obtained using instrumented walker handles. Energy expenditure index was obtained using the heart rate method (EEIHR) by subtracting resting heart rate from walking heart rate, and dividing by the walking speed. Correlations were sought between the kinetic variables and the EEIHR and temporal and stride parameters. In general, anterior walker use was associated with a higher EEIHR. Several kinetic variables correlated well with temporal and stride parameters, as well as the EEIHR. All of the significant correlations (r>0.80; pwalker use and involved joint reaction forces (JRF) rather than moments. Some variables showed multiple strong correlations during anterior walker use, including the medial JRF in the wrist, the posterior JRF in the elbow, and the inferior and superior JRFs in the shoulder. The observed correlations may indicate a relationship between the force used to advance the body forward within the walker frame and an increased EEIHR. More work is needed to refine the correlations, and to explore relationships with other variables, including the joint kinematics.

  6. A new walker with upper trunk suspension system for severely disabled patients.

    Science.gov (United States)

    Scoppetta, C; Scoppetta, M

    2013-10-01

    We have recently designed a new type of walker for those severely disabled patients who cannot walk with commonly used medical walkers. A drawing and the description of this new walker is reported in order to permit the worldwide companies as well as artisans to develop and produce it for the people affected from severe motor problems. This walker supposes the patient wearing either a modified climbing harness or equipped clothes and being suspended to the walking frame. It consists in two series of bands suspending the patient from the frame; the upper one suspends him for the upper part of his trunk, the lower one by his pelvis. This walker is suggested for patients belonging to three principal groups: (1) Persons who have no trunk control (e.g.: patients affected by severe stroke or ataxias). (2) Persons whose walk is allowed only if they achieve a significant reduction (up to 30-40%) of the their body weight charging on trunk, spine, and lower limbs. (3) Persons who need a differentiated reduction of the body weight either among anterior and posterior side or among their right and left part of the body (hemiparesis, Parkinson disease, scoliosis, kyphosis). Creating this walker is easy; producing costs are low; there are no maintenance costs.

  7. Dynamics of unvisited sites in the presence of mutually repulsive random walkers

    International Nuclear Information System (INIS)

    Das, Pratap Kumar; Dasgupta, Subinay; Sen, Parongama

    2007-01-01

    We have considered the persistence of unvisited sites of a lattice, i.e., the probability S(t) that a site remains unvisited till time t in the presence of mutually repulsive random walkers in one dimension. The dynamics of this system has direct correspondence to that of the domain walls in a certain system of Ising spins where the number of domain walls becomes fixed following a zero-temperature quench. Here we get the result that S(t) ∼ exp(-αt β ) where β is close to 0.5 and α a function of the density of the walkers ρ. The fraction of persistent sites in the presence of independent walkers of density ρ' is known to be S'(t) = exp(-2√(2/π ρ't 1/2 ). We show that a mapping of the interacting walkers' problem to the independent walkers' problem is possible with ρ' = ρ/(1 - ρ) provided ρ' and ρ are small. We also discuss some other intricate results obtained in the interacting walkers' case

  8. CommWalker: correctly evaluating modules in molecular networks in light of annotation bias.

    Science.gov (United States)

    Luecken, M D; Page, M J T; Crosby, A J; Mason, S; Reinert, G; Deane, C M

    2018-03-15

    Detecting novel functional modules in molecular networks is an important step in biological research. In the absence of gold standard functional modules, functional annotations are often used to verify whether detected modules/communities have biological meaning. However, as we show, the uneven distribution of functional annotations means that such evaluation methods favor communities of well-studied proteins. We propose a novel framework for the evaluation of communities as functional modules. Our proposed framework, CommWalker, takes communities as inputs and evaluates them in their local network environment by performing short random walks. We test CommWalker's ability to overcome annotation bias using input communities from four community detection methods on two protein interaction networks. We find that modules accepted by CommWalker are similarly co-expressed as those accepted by current methods. Crucially, CommWalker performs well not only in well-annotated regions, but also in regions otherwise obscured by poor annotation. CommWalker community prioritization both faithfully captures well-validated communities and identifies functional modules that may correspond to more novel biology. The CommWalker algorithm is freely available at opig.stats.ox.ac.uk/resources or as a docker image on the Docker Hub at hub.docker.com/r/lueckenmd/commwalker/. deane@stats.ox.ac.uk. Supplementary data are available at Bioinformatics online.

  9. Parasitismo entre especies (Diptera, Hymenoptera en los nidos de Stictia signata (Hymenoptera: Sphecidae

    Directory of Open Access Journals (Sweden)

    Julio A. Genaro

    1999-09-01

    Full Text Available S. signata es una de las avispas de la arena más frecuentemente observada en los cayos y las costas de Cuba. Las hembras construyen los nidos en la arena y los abastecen con moscas, para alimentar a la descendencia. Se describe la conducta de dos especies: Liohippelates n. sp. circa collusor (Diptera: Chloropidae y Hexacola sp. (Hymenoptera: Eucoilidae para penetrar al interior de los nidos de S. signata. Las observaciones se efectuaron durante 1989 hasta 1991, en playa Caimito, sur de la provincia de La Habana, Cuba. Liohippelates cleptoparasitó el 100% de los nidos. Sus larvas necrófagas se alimentaron de los restos de las presas dejadas por la larva de S. signata, sin afectarla. Sólo en un caso la larva mostró signos de mortalidad, porque además del número alto de cleptoparásitos inmaduros, habían 53 moscas adultas alimentándose de los fluidos corporales de las presas. Hexacola sp. fue un parasitoide de las larvas de Liohippelates, en el interior de las celdillas. A pesar del elevado cleptoparasitismo, la población del esfécido se mantuvo elevada durante los años de observación.Stictia signata is one of the most frequently observed sand wasps in the Cuban keys and coasts. Females build their nests in the sand and supply them with flies to feed offspring. Here, I describe the behavior of two species, Liohippelates n. sp. near collusor (Diptera: Chloropidae and Hexacola sp. (Hymenoptera: Eucoilidae, which enter the nests of S. signata. The observations were carried out from 1989 through 1991 in Caimito beach, Southern Havana province, Cuba. Liohippelates inhabited 100% of the nests. Its necrofagous larvae fed on the remnants of prey left by the larva of S. signata, without affecting the larva. Only in one case did the larva show signs of mortality because, apart from the high number of immature cleptoparasites, there were 53 adult flies feeding on prey body fluids. Hexacola sp. parasitized the larvae of Liohippelates within the

  10. An Architect Cicada in Brazilian Rainforest: Guyalna chlorogena (Walker).

    Science.gov (United States)

    Béguin, C F

    2017-04-01

    To study the noteworthy nest building behavior of the nymph of the Brazilian Rainforest cicada Guyalna chlorogena (Walker) during the last year of its underground life, we monitored a large number of edifices, consisting of a vertical well (up to 1 m deep) with a turret (20 to 40 cm tall) on top, and we also performed experiments. We have shown that the buildings are occupied by a single nymph, male or female, which increases the height of its turret each night by about 3 cm, during a short active growing phase. The nymph softens and reshapes the apex by pushing upwards a lump of freshly mixed soaked clay, without any opening present, i. e., without ever exposing itself to the outside. We also established that the nymph is very active once its building is achieved. For example, it restores the height of the turret to its original value when shortening and opens the top of its building in case of variation of environmental parameters. Finally, we have shown how the nymph opens its edifice to reach the outside for molting into an adult stage (imago). With this work, we contributed to a better understanding of the nesting behavior of Amazon cicadas.

  11. Problems of older persons using a wheeled walker.

    Science.gov (United States)

    Lindemann, Ulrich; Schwenk, Michael; Klenk, Jochen; Kessler, Max; Weyrich, Michael; Kurz, Franziska; Becker, Clemens

    2016-04-01

    Wheeled walkers (WWs) are used to improve mobility and for fall prevention in older persons, but not all users are satisfied with the usability of WWs. Intelligent WWs are being developed to improve the usability. The aim of this study was to support the development of intelligent WWs by investigating possible problems of using a WW. This study investigated 22 geriatric in-patients (median age 82 years) with and without their WW while opening a door against the direction of walking and passing through. Other possible problems when using WWs were identified by interview. Walking through the door was faster without than with using the WW (8.71 versus 12.86 s, p < 0.001), while interference between door and WW was documented in 41 of 44 (93 %) cases. Backward walking performance was better when using a WW with regard to gait speed, step width and walk ratio (all p < 0.002). Most referred problems when using a WW were walking downhill (83 %) and uphill (77 %) and obstacle crossing in general (77 %). Problems with opening a door against the direction of walking and the optimization of downhill and uphill walking as well as obstacle crossing should be regarded when developing an intelligent WW.

  12. Technical characteristics of elite junior men and women race walkers.

    Science.gov (United States)

    Hanley, B; Bissas, A; Drake, A

    2014-12-01

    Successful coaching in race walking requires a thorough understanding of the biomechanical principles underlying this unique form of gait. The purpose of this study was to analyze elite male and female junior race walkers and identify key kinematic variables. Twenty junior men and 20 junior women were videoed as they competed over 10 km in the 8th European Cup Race Walking. Three-dimensional kinematic data were obtained using motion analysis software (SIMI, Munich). Step length and cadence were correlated with speed in both sexes, and greater step lengths were the kinematic reason for junior men's faster walking speeds. While cadence did not differ between junior men and junior women, there was a difference in proportion of step time spent in contact. There were some differences between genders for upper body joint angles (e.g., elbow) but there were few differences within lower limb joint angles. Although some technical aspects (e.g., pelvic and shoulder girdle rotation) appeared undeveloped, it was noteworthy that most athletes achieved full knee extension at initial contact in accordance with the rules. However, in many athletes flight times were evident that might present problems during the transition to the higher standards of senior competition. There was a large range of ability among both sexes and coaches are advised to ensure that technical development continues during the transition to senior competition.

  13. Potential Positive Effects of Pesticides Application on (Walker (Lepidoptera: Insecta

    Directory of Open Access Journals (Sweden)

    Guo-Qing Yang

    2014-01-01

    Full Text Available In China, the pink stem borer (PSB Sesamia inferens (Walker (Lepidoptera: Noctuidae has become a rice pest in some rice-producing regions. The cause of this shift from secondary to major pest is unknown. The major purpose of this study was to examine the effect of five commonly used pesticides in rice fields on reproduction of PSB and on biochemical substances of rice plants. The results showed that the weight of pupae developed from 1st instar larvae treated with 2 mg/L triazophos and the number of eggs laid by emerged females from the treatment were significantly greater than those of the control, increasing by 26.2% and 47%, respectively. In addition, a nontarget insecticide, pymetrozine 100 mg/L, and a target insecticide, chlorantraniliprole 2 mg/L, stimulated reproduction of PSB. Biochemical measurement showed that foliar sprays of these pesticides resulted in significant reductions of contents of resistant substances, flavonoids and phenolic acids, in rice plants. For example, flavonoids and phenolic acids of rice plants treated with triazophos reduced by 48.5% and 22.4%, respectively, compared to the control. Therefore, we predicted that the application of some pesticides, eg triazophos and chlorantraniliprole, may be the cause of the increase in the population numbers of PSB in rice fields.

  14. Third annual Walker Branch Watershed research symposium. Program and abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    The methods and concepts of watershed research, originally applied in an experimental or monitoring mode to relatively small catchments, are increasingly being used at larger scales and for specific applied problems. Research at Oak Ridge National Laboratory, the Tennessee Valley Authority, the US Forest Service, and other agencies and institutions participating in this symposium reflects research over a broad range of spatial scales that is being integrated through large-scale experiments along with computer modeling and graphical interfaces. These research projects address the basic atmospheric, geophysical, biogeochemical, and biological processes that regulate the responses of forested ecosystems to natural environmental variation and anthropogenic stresses. Regional and global issues addressed by presentations include emissions of carbon dioxide, methane, and other hydrocarbons; deposition of sulfate, nitrate, and mercury; land-use changes; biological diversity; droughts; and water quality. The reports presented in this symposium illustrate a wide range of methods and approaches and focus more on concepts and techniques than on a specific physical site. Sites and projects that have contributed research results to this symposium include Walker Branch Watershed (DOE), the Coweeta Hydrologic Laboratory and LTER site (USFS and NSF), Great Smoky Mountains National Park (research funded by NPS, TVA, and EPRI), Imnavait Creek, Alaska (DOE), the TVA-Norris Whole-tree Facility (TVA and EPRI), and DOE`s Biomass Program.

  15. Fourth annual Walker Branch Watershed research symposium: Program and abstracts

    International Nuclear Information System (INIS)

    1993-03-01

    The methods and concepts of watershed research, originally applied in an experimental or monitoring mode to relatively small catchments, are increasingly being used at larger scales and for specific applied problems. Research at Oak Ridge National Laboratory, the Tennessee Valley Authority, the US Forest Service, and other agencies and institutions participating in this symposium reflects research over a broad range of spatial scales that is being integrated through large-scale experiments along with computer modeling and graphical interfaces. These research projects address the basic atmospheric, geophysical, biogeochemical, and biological processes that regulate the responses of forested ecosystems to natural environmental variation and anthropogenic stresses. This symposium highlights the use of large-scale ecosystem experiments to address environmental issues of global concern. These experiments provide the only effective way to test models of ecosystem response that are based on the current state of knowledge of hydrology, biogeochemistry, plant physiology, and other ecosystem processes. Major environmental problems that are being addressed include acidic deposition and nitrogen loading (Bear Brook Watershed, Maine; and the Girdsjoen Covered Catchment, Sweden); climate warming (Soil Warming Experiment, Maine); and altered rainfall amounts (Savannah River Loblolly Pine Soil Water Manipulation and the Walker Branch Watershed Throughfall Displacement Experiment)

  16. Estágios imaturos de Spodoptera cosmioides (Walker (Lepidoptera, Noctuidae Immature stages of Spodoptera cosmioides (Walker (Lepidoptera, Noctuidae

    Directory of Open Access Journals (Sweden)

    Maurício M. Zenker

    2007-03-01

    Full Text Available O gênero Spodoptera Guenée, 1852 é composto por trinta espécies de distribuição cosmopolita, encontradas com maior freqüência em locais de clima mais quente. Quinze espécies são pragas agrícolas, apresentando alto grau de polifitofagia, alimentando-se de importantes culturas como soja, milho, arroz e batata inglesa. A morfologia dos estágios imaturos dos representantes deste gênero é pouco conhecida, sendo que um terço das espécies não possui descrição de seus estágios imaturos. Entre as espécies ocorrentes no Brasil, sem tais informações, destaca-se Spodoptera cosmioides (Walker, 1858. Este trabalho caracterizou detalhadamente seus principais aspectos morfológicos, passíveis de serem utilizados na identificação taxonômica dos estágios imaturos; contém dados referentes à morfologia, destacando-se a área micropilar dos ovos, quetotaxia, fiandeira e coloração da fase de lagarta e disposição dos apêndices e aberturas naturais nas pupas.There are 30 species in the genus Spodoptera Guenée, 1852 worldwide distributed, occurring mainly in the warm regions. Fifteen species are considered plagues feeding on several important agricultural crops as soybean, corn, rice and potato. The immature stages morphology of this genus is not well known. In about one third of the most economically relevant species, the caterpillar is not described and, also, few information related to the chrysalis and the eggs are available. Spodoptera cosmioides (Walker, 1858 is one of the most important pest among the noctuids occurring in Brazil with no information about its immature stages. Detailed morphological descriptions and illustrations of the immature stages of S. cosmioides, as micropilar area of the egg, chaetotaxy, spinneret, caterpillar ground color, arrangement of the appendages and natural openings of the pupa, are presented for the first time. Taxonomic remarks are also provided.

  17. Abridged life tables for Cephalonomia stephanoderis and Prorops nasuta (Hymenoptera: Bethylidae) Parasitoids of Hypothenemus hampei (Coleoptera: Scolytidae) reared on artificial diet

    Science.gov (United States)

    Biological aspects and demographic parameters of Cephalonomia stephanoderis Betrem (Hymenoptera: Bethylidae) and Prorops nasuta Waterston (Hymenoptera: Bethylidae) parasitoids of the coffee berry borer (CBB), Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) were investigated usi...

  18. Can use of walkers or canes impede lateral compensatory stepping movements?

    Science.gov (United States)

    Bateni, Hamid; Heung, Evelyn; Zettel, John; McLlroy, William E; Maki, Brian E

    2004-08-01

    Although assistive devices, such as walkers and canes are often prescribed to aid in balance control, recent studies have suggested that such devices may actually increase risk of falling. In this study, we investigated one possible mechanism: the potential for walkers or canes to interfere with, or constrain, lateral movement of the feet and thereby impede execution of compensatory stepping reactions during lateral loss of balance. Lateral stepping reactions were evoked, in 10 healthy young adults (ages 22-27 years), by means of sudden unpredictable medio-lateral support surface translation. Subjects were tested while holding and loading a standard pickup walker or single-tip cane or while using no assistive device (hands free or holding an object). Results supported the hypothesis that using a walker or cane can interfere with compensatory stepping. Collisions between the swing-foot and mobility aid were remarkably frequent when using the walker (60% of stepping reactions) and also occurred in cane trials (11% of stepping reactions). Furthermore, such collisions were associated with a significant reduction (26-37%) in lateral step length. It appeared that subjects were sometimes able to avoid collision by increasing the forward or backward displacement of the swing-foot or by moving the cane; however, attempts to lift the walker out of the way occurred rarely and were usually impeded due to collision between the contralateral walker post and stance foot. The fact that compensatory stepping behavior was altered significantly in such a healthy cohort clearly demonstrates some of the safety limitations inherent to these assistive devices, as currently designed. Copyright 2003 Elsevier B.V.

  19. A NEW SPECIES OF INVASIVE GALL WASP (HYMENOPTERA: EULOPHIDAE: TETRASTICHINAE) ON BLUE GUM (EUCALYPTUS GLOBULUS) IN CALIFORNIA

    Science.gov (United States)

    The blue gum gall wasp, Selitrichodes globulus La Salle & Gates (Hymenoptera: Eulophidae: Tetrastichinae), is described as an invasive gall inducer on blue gum, Eucalyptus globulus (Myrtaceae), in California....

  20. A new species of Chelonus (Areselonus) (Hymenoptera, Braconidae) from India reared from Acrocercops lysibathra (Meyrick) on Cordia latifolia Roxb.

    OpenAIRE

    Ahmad, Zubair; Ghramh, Hamed A.

    2018-01-01

    Chelonus (Areselonus) spinigaster sp. n., (Hymenoptera: Braconidae: Cheloninae) is described from India. The new species was reared from the moth species Acrocercops lysibathra (Meyr.) on Cordia latifolia Roxb.

  1. A new species of Chelonus (Areselonus) (Hymenoptera, Braconidae) from India reared from Acrocercops lysibathra (Meyrick) on Cordia latifolia Roxb.

    Science.gov (United States)

    Ahmad, Zubair; Ghramh, Hamed A

    2018-01-01

    Chelonus (Areselonus) spinigaster sp. n. , (Hymenoptera: Braconidae: Cheloninae) is described from India. The new species was reared from the moth species Acrocercops lysibathra (Meyr.) on Cordia latifolia Roxb.

  2. Obituary: Richard L. (Dick) Walker, Jr., 1938-2005

    Science.gov (United States)

    Pier, Jeffrey R.; Mason, Brian

    2005-12-01

    Dick Walker, 67, died 30 March 2005 in Flagstaff, AZ, following a long illness. He was born on 9 March 1938 in Hampton, Iowa and grew up in Waterloo, Iowa. As a child, Dick was fascinated with astronomy and built his own telescope. He saved his pennies and bought and read every book on the subject he could find. He also raised pigeons, naming four of them Hertzsprung, Hoyle, Gamow, and Kron. In 1957, the year Sputnik was launched, Dick began his college studies at the University of Northern Iowa in Cedar Falls. In 1959, he transferred to the State University of Iowa (subsequently renamed the University of Iowa) in Iowa City, where he earned a BA degree in astronomy and physics in 1963. He joined the staff of the U.S. Naval Observatory in Washington, DC, where he worked in the Time Service Division for a year before his assignment to the Astrometry and Astrophysics Division. Dick relocated to Flagstaff, AZ, in 1966 to continue his Naval Observatory service at the Flagstaff Station. His retirement in May 1999, ended a thirty-six-year career with USNO. Dick was first and foremost an observational astronomer. From the mid 1960s through the late 1970s, much of Dick's time was devoted to the measurement of binary stars, observing with the 12-inch and 26-inch refractors in Washington and later the 40-inch and 61-inch reflectors in Flagstaff. He also made many trips to Lick Observatory to work with the 36-inch Clark Refractor there. During this time he consulted with Charles Worley, who was observing on the 26-inch, to make sure time was well-spent examining doubles that could not be observed in Washington. This period of observing overlapped with the early years of speckle interferometry, and Dick's observations, made with the largest telescope used for micrometry at the time, were very important for ascertaining the veracity of this new technique. He was a studious and very careful observer of doubles and made over 8,000 measures, resulting in almost 3,000 mean positions

  3. Trophobiosis in the arboricolous ant .i.Liometopum microcephalum./i. (Hymenoptera: Formicidae: Dolichoderinae)

    Czech Academy of Sciences Publication Activity Database

    Schlaghamerský, J.; Kašpar, J.; Petráková, L.; Šustr, Vladimír

    2013-01-01

    Roč. 110, č. 2 (2013), s. 231-239 ISSN 1210-5759 Institutional support: RVO:60077344 Keywords : Hymenoptera * arboricolous * ants * trophobiosis Subject RIV: EG - Zoology Impact factor: 1.076, year: 2013

  4. Two new species of the genus Peristenus Foerster (Hymenoptera: Braconidae: Euphorinae) from the Canary Islands

    NARCIS (Netherlands)

    Achterberg, van C.; Guerrero, E.R.

    2003-01-01

    Two new species of the genus Peristenus Foerster (Hymenoptera: Braconidae: Euphorinae) from the Canary Islands are described and illustrated: Peristenus angifemoralis spec. nov. from Tenerife, and P. gloriae spec. nov. from Gran Canaria and Tenerife.

  5. Natural history of Hymenoptera venom allergy in Eastern Spain.

    Science.gov (United States)

    Fernandez, J; Soriano, V; Mayorga, L; Mayor, M

    2005-02-01

    The natural history of stings, the clinical reaction of the patient and in vivo and in vitro tests are necessary parameters to assess before initiating Hymenoptera venom immunotherapy. In the decision to initiate immunotherapy with Hymenoptera venom, it is not usual to evaluate the natural history of the disease, which seems to be self-limiting and therefore of variable clinical significance. Our aim was to determine the natural history of Hymenoptera hypersensitivity over 4 consecutive years in a rural Mediterranean population. An epidemiological study of Hymenoptera sting reactions and possible sensitivity was carried out in 145 randomly selected subjects out of a rural Mediterranean population of 600. Seventy-two subjects, including those with a history of anaphylaxis, completed the 4-year study. The nature of their clinical reactions, age, sex, history of atopy, profession, family history of reactions to Hymenoptera insects, time elapsed since the last sting, number of stings and specific IgE and IgG were determined (the latter, to the three most important insects in the area: Apis mellifera, Polistes dominulus, and Vespula germanica). Of the 72 subjects, four subjects had systemic reactions (SR), 23 had large local reaction (LLR) and all the others (117) was minor local reactions. None who had experienced an SR had a repeat SR when re-stung over the 4-year study. Of those with LLR, 12 subjects had the same type of reaction and 11 experienced more mild local reactions when re-stung. In the SR and local reaction groups, IgE to honey bee (Hb) increased significantly during the study period, whereas in those with only LLR, specific IgE to wasp (Polistes) decreased. Specific IgG to Polistes and Vespula (wasps) decreased significantly, whereas there was no change in the specific IgG to Hb in any of the groups. The number of stings per year decreased at the end of the study in all groups, but positive-specific IgG was higher in subjects with the greatest number of

  6. Extraction of user's navigation commands from upper body force interaction in walker assisted gait.

    Science.gov (United States)

    Frizera Neto, Anselmo; Gallego, Juan A; Rocon, Eduardo; Pons, José L; Ceres, Ramón

    2010-08-05

    The advances in technology make possible the incorporation of sensors and actuators in rollators, building safer robots and extending the use of walkers to a more diverse population. This paper presents a new method for the extraction of navigation related components from upper-body force interaction data in walker assisted gait. A filtering architecture is designed to cancel: (i) the high-frequency noise caused by vibrations on the walker's structure due to irregularities on the terrain or walker's wheels and (ii) the cadence related force components caused by user's trunk oscillations during gait. As a result, a third component related to user's navigation commands is distinguished. For the cancelation of high-frequency noise, a Benedict-Bordner g-h filter was designed presenting very low values for Kinematic Tracking Error ((2.035 +/- 0.358).10(-2) kgf) and delay ((1.897 +/- 0.3697).10(1)ms). A Fourier Linear Combiner filtering architecture was implemented for the adaptive attenuation of about 80% of the cadence related components' energy from force data. This was done without compromising the information contained in the frequencies close to such notch filters. The presented methodology offers an effective cancelation of the undesired components from force data, allowing the system to extract in real-time voluntary user's navigation commands. Based on this real-time identification of voluntary user's commands, a classical approach to the control architecture of the robotic walker is being developed, in order to obtain stable and safe user assisted locomotion.

  7. [Effect of abducens orthosis combined with walker on developmental dysplasia of the hip].

    Science.gov (United States)

    Hu, Zhiyong; Xu, Yongqiang; Liang, Jieyu; Li, Kanghua; Liao, Qiande

    2009-07-01

    To evaluate the effect of abducens orthosis combined with walker on developmental dysplasia of the hip (DDH). A total of 126 patients (224 hips) with DDH aged 6-36 months in Xiangya Hospital was randomly divided into 2 groups: an orthosis combined with walker group and an improved hip frog cast fixation group. Seventy patients (130 hips) were treated by the orthosis combined with walker and 56 patients (94 hips) were treated by the improved hip frog cast fixation. We compared the effect and complications of the 2 groups. The fineness rates of the orthosis combined with walker group and the improved hip frog cast fixation group were 89.2% and 90.4%, respectively, with no significant difference (P>0.05). The rate of femoral head osteonecrosis in the orthosis combined with walker group was significantly lower than that in the improved hip frog cast fixation group (1.5% vs. 5.3%,Pwalker has a lower proportion of femoral head osteonecrosis, but a higher proportion of re-dislocation.

  8. Does the Walker Lane extend through the Nevada test site region?

    International Nuclear Information System (INIS)

    Fridrich, C.; O'Leary, D.

    1993-01-01

    The southeastern terminus of the Walker Lane is poorly defined and poorly understood. Recent work in and around the Nevada Test Site (NTS) suggests the presence of a structural zone that may be an extension of the Walker Lane, and that may be continuous with the Las Vegas valley shear zone farther to the southeast. Unlike the Walker Lane, large through-going strike-slip faults have not been found in the NTS zone. Instead, the strike-slip faults present are few, are relatively short, commonly consist of diffuse fault zones, are interconnected poorly if at all, and largely appear to represent zones of accommodation between domains in which extension occurred at different times and to different degrees. However, the majority of these right-slip and left-slip faults are northwest-trending and northeast-trending, respectively, suggesting that plate motions may have played a role in the creation of these accommodation zones. An obstacle to understanding the NTS zone is that major ignimbrite sheets and calderas of the southwestern Nevada volcanic field (SNVF) formed in this zone at the height of late Tertiary tectonic activity, possibly burying much of the structural evidence. The NTS zone could represent an intersection of the Walker Lane with another major structural feature, a significant bend in the Walker Lane, or a transtensional tear that localized accommodation structures as well as the prominent late Miocene calderas of the SNVF. Ongoing field work is aimed at determining which of these and competing interpretations is best

  9. A New Controller for a Smart Walker Based on Human-Robot Formation.

    Science.gov (United States)

    Valadão, Carlos; Caldeira, Eliete; Bastos-Filho, Teodiano; Frizera-Neto, Anselmo; Carelli, Ricardo

    2016-07-19

    This paper presents the development of a smart walker that uses a formation controller in its displacements. Encoders, a laser range finder and ultrasound are the sensors used in the walker. The control actions are based on the user (human) location, who is the actual formation leader. There is neither a sensor attached to the user's body nor force sensors attached to the arm supports of the walker, and thus, the control algorithm projects the measurements taken from the laser sensor into the user reference and, then, calculates the linear and angular walker's velocity to keep the formation (distance and angle) in relation to the user. An algorithm was developed to detect the user's legs, whose distances from the laser sensor provide the information necessary to the controller. The controller was theoretically analyzed regarding its stability, simulated and validated with real users, showing accurate performance in all experiments. In addition, safety rules are used to check both the user and the device conditions, in order to guarantee that the user will not have any risks when using the smart walker. The applicability of this device is for helping people with lower limb mobility impairments.

  10. The fire-walker's high: affect and physiological responses in an extreme collective ritual.

    Directory of Open Access Journals (Sweden)

    Ronald Fischer

    Full Text Available How do people feel during extreme collective rituals? Despite longstanding speculation, few studies have attempted to quantify ritual experiences. Using a novel pre/post design, we quantified physiological fluctuations (heart rates and self-reported affective states from a collective fire-walking ritual in a Mauritian Hindu community. Specifically, we compared changes in levels of happiness, fatigue, and heart rate reactivity among high-ordeal participants (fire-walkers, low-ordeal participants (non-fire-walking participants with familial bonds to fire-walkers and spectators (unrelated/unknown to the fire-walkers. We observed that fire-walkers experienced the highest increase in heart rate and reported greater happiness post-ritual compared to low-ordeal participants and spectators. Low-ordeal participants reported increased fatigue after the ritual compared to both fire-walkers and spectators, suggesting empathetic identification effects. Thus, witnessing the ritualistic suffering of loved ones may be more exhausting than experiencing suffering oneself. The findings demonstrate that the level of ritual involvement is important for shaping affective responses to collective rituals. Enduring a ritual ordeal is associated with greater happiness, whereas observing a loved-one endure a ritual ordeal is associated with greater fatigue post-ritual.

  11. Race walking gait and its influence on race walking economy in world-class race walkers.

    Science.gov (United States)

    Gomez-Ezeiza, Josu; Torres-Unda, Jon; Tam, Nicholas; Irazusta, Jon; Granados, Cristina; Santos-Concejero, Jordan

    2018-03-06

    The aim of this study was to determine the relationships between biomechanical parameters of the gait cycle and race walking economy in world-class Olympic race walkers. Twenty-One world-class race walkers possessing the Olympic qualifying standard participated in this study. Participants completed an incremental race walking test starting at 10 km·h -1 , where race walking economy (ml·kg -1 ·km -1 ) and spatiotemporal gait variables were analysed at different speeds. 20-km race walking performance was related to race walking economy, being the fastest race walkers those displaying reduced oxygen cost at a given speed (R = 0.760, p < 0.001). Longer ground contact times, shorter flight times, longer midstance sub-phase and shorter propulsive sub-phase during stance were related to a better race walking economy (moderate effect, p < 0.05). According to the results of this study, the fastest race walkers were more economi cal than the lesser performers. Similarly, shorter flight times are associated with a more efficient race walking economy. Coaches and race walkers should avoid modifying their race walking style by increasing flight times, as it may not only impair economy, but also lead to disqualification.

  12. Hydrologic data for the Walker River Basin, Nevada and California, water years 2010–14

    Science.gov (United States)

    Pavelko, Michael T.; Orozco, Erin L.

    2015-12-10

    Walker Lake is a threatened and federally protected desert terminal lake in western Nevada. To help protect the desert terminal lake and the surrounding watershed, the Bureau of Reclamation and U.S. Geological Survey have been studying the hydrology of the Walker River Basin in Nevada and California since 2004. Hydrologic data collected for this study during water years 2010 through 2014 included groundwater levels, surface-water discharge, water chemistry, and meteorological data. Groundwater levels were measured in wells, and surface-water discharge was measured in streams, canals, and ditches. Water samples for chemical analyses were collected from wells, streams, springs, and Walker Lake. Chemical analyses included determining physical properties; the concentrations of major ions, nutrients, trace metals, dissolved gases, and radionuclides; and ratios of the stable isotopes of hydrogen and oxygen. Walker Lake water properties and meteorological parameters were monitored from a floating platform on the lake. Data collection methods followed established U.S. Geological Survey guidelines, and all data are stored in the National Water Information System database. All of the data are presented in this report and accessible on the internet, except multiple-depth Walker Lake water-chemistry data, which are available only in this report.

  13. Spatial Analysis of Agricultural Landscape and Hymenoptera Biodiversity at Cianjur Watershed

    Directory of Open Access Journals (Sweden)

    YAHERWANDI

    2006-12-01

    Full Text Available Hymenoptera is one of the four largest insect order (the other three are Coleoptera, Diptera, and Lepidoptera. There are curerently over 115 000 described Hymenoptera species. It is clear that Hymenoptera is one of the major components of insect biodiversity. However, Hymenoptera biodiversity is affected by ecology, environment, and ecosystem management. In an agricultural areas, the spatial structure, habitat diversity, and habitat composition may vary from cleared landscapes to structurally rich landscape. Thus, it is very likely that such large-scale spatial patterns (landscape effects may influence local biodiversity and ecological functions. Therefore, the objective of this research were to study diversity and configuration elements of agricultural landscapes at Cianjur Watershed with geographical information sytems (GIS and its influence on Hymenoptera biodiversity. The structural differences between agricultural landscapes of Nyalindung, Gasol, and Selajambe were characterized by patch analyst with ArcView 3.2 of digital land use data. Results indicated that class of land uses of Cianjur Watershed landscape were housing, mixed gardens, talun and rice, vegetable, and corn fields. Landscape structure influenced the biodiversity of Hymenoptera. Species richness and the species diversity were higher in Nyalindung landscape compare to Gasol and Selajambe landscape.

  14. Pengaruh Habitat Sekitar Lahan Persawahan dan Umur Tanaman Padi terhadap Keanekaragaman Hymenoptera Parasitika

    Directory of Open Access Journals (Sweden)

    Nina Herlina

    2015-09-01

    Full Text Available As the largest group of biological control agents, Parasitic Hymenoptera play important role in controlling pest outbreak in agricultural habitat. Unfortunately, there is lack of information about how these parasitoids occur in agricultural habitat related to condition of surrounding habitat and phenology of crop plant. The objective of this research was to study the effect of rice field surrounding habitat and age of rice plant on the diversity of Parasitic Hymenoptera. Research area was located in Carang Pulang Village, Dramaga, Bogor. We selected four blocks which represented different of habitat condition and age of rice plant. Each block was set six yellow pan traps (with minimum distance 20 meter and one malaise trap. Sampling of insects were conducted weekly from 6 to 12 week after planting. From this research, we collected 1,833 individual of Hymenoptera (without ants belong to 9 superfamilies, 23 families, and 216 species. Parasitic Hymenoptera was more abundant (96% and species rich (84% than Aculeata. Rice field surrounding habitat (block and age of rice field significantly affect the diversity of Parasitic Hymenoptera. We found positively correlation between age of rice plant and species richness of Parasitic Hymenoptera.

  15. Taxonomic and functional responses to fire and post-fire management of a Mediterranean hymenoptera community.

    Science.gov (United States)

    Mateos, Eduardo; Santos, Xavier; Pujade-Villar, Juli

    2011-11-01

    Fire is one of the commonest disturbances worldwide, transforming habitat structure and affecting ecosystem functioning. Understanding how species respond to such environmental disturbances is a major conservation goal that should be monitored using functionally and taxonomically diverse groups such as Hymenoptera. In this respect, we have analyzed the taxonomic and functional response to fire and post-fire management of a Hymenoptera community from a Mediterranean protected area. Thus, Hymenoptera were sampled at fifteen sites located in three burnt areas submitted to different post-fire practices, as well as at five sites located in peripheral unburnt pine forest. A total of 4882 specimens belonging to 33 families, which were classified into six feeding groups according to their dietary preferences, were collected. ANOVA and Redundancy Analyses showed a taxonomic and functional response to fire as all burnt areas had more Hymenoptera families, different community composition and higher numbers of parasitoids than the unburnt area. Taxonomic differences were also found between burnt areas in terms of the response of Hymenoptera to post-fire management. In general the number of parasitoids was positively correlated to the number of potential host arthropods. Parasitoids are recognized to be sensitive to habitat changes, thus highlighting their value for monitoring the functional responses of organisms to habitat disturbance. The taxonomic and functional responses of Hymenoptera suggest that some pine-forest fires can enhance habitat heterogeneity and arthropod diversity, hence increasing interspecific interactions such as those established by parasitoids and their hosts.

  16. Taxonomic and Functional Responses to Fire and Post-Fire Management of a Mediterranean Hymenoptera Community

    Science.gov (United States)

    Mateos, Eduardo; Santos, Xavier; Pujade-Villar, Juli

    2011-11-01

    Fire is one of the commonest disturbances worldwide, transforming habitat structure and affecting ecosystem functioning. Understanding how species respond to such environmental disturbances is a major conservation goal that should be monitored using functionally and taxonomically diverse groups such as Hymenoptera. In this respect, we have analyzed the taxonomic and functional response to fire and post-fire management of a Hymenoptera community from a Mediterranean protected area. Thus, Hymenoptera were sampled at fifteen sites located in three burnt areas submitted to different post-fire practices, as well as at five sites located in peripheral unburnt pine forest. A total of 4882 specimens belonging to 33 families, which were classified into six feeding groups according to their dietary preferences, were collected. ANOVA and Redundancy Analyses showed a taxonomic and functional response to fire as all burnt areas had more Hymenoptera families, different community composition and higher numbers of parasitoids than the unburnt area. Taxonomic differences were also found between burnt areas in terms of the response of Hymenoptera to post-fire management. In general the number of parasitoids was positively correlated to the number of potential host arthropods. Parasitoids are recognized to be sensitive to habitat changes, thus highlighting their value for monitoring the functional responses of organisms to habitat disturbance. The taxonomic and functional responses of Hymenoptera suggest that some pine-forest fires can enhance habitat heterogeneity and arthropod diversity, hence increasing interspecific interactions such as those established by parasitoids and their hosts.

  17. Directional transport of colloids inside a bath of self-propelling walkers.

    Science.gov (United States)

    Merlitz, Holger; Wu, Chenxu; Sommer, Jens-Uwe

    2017-05-24

    We present a setup in which passive colloids inside a solvent are moved to the boundaries of the container. The directional transport is facilitated by self-propelling microparticles ("walkers") with an activity gradient, which reduces their propulsion in the vicinity of bounding walls. An attractive interaction leads to the adsorption of walkers onto the colloid-surfaces in regions of low walker activity. It is shown that the activity gradient generates a free energy gradient which in turn acts as a driving force on the passive colloids. We carry out molecular dynamics simulations and present approaches to a theoretical description of the involved processes. Although the simulation data are not reproduced on a fully quantitative level, their qualitative features are covered by the model. The effect described here may be applied to facilitate a directional transport of drugs or to eliminate pollutants.

  18. Corrections to the Walker-Thompson estimate of the cascade volume

    International Nuclear Information System (INIS)

    Swaminarayan, S.; Nastasi, M.

    2009-01-01

    Sigmund [P. Sigmund, Appl. Phys. Lett. 25 (1974) 169] analytically predicted that the ratio of cascade volume to energy distribution volume should follow a universal curve that is sigmoidal in shape. Subsequent Monte Carlo simulations by Walker and Thompson [R.S. Walker, D.A. Thompson, Radiat. Eff. 37 (1978) 113] showed that although this curve is sigmoidal in shape, the curve is different for different materials with large deviations from Sigmund's prediction at high M 2 /M 1 . Our analysis of the Walker and Thompson approach has revealed an error in the analytical equations used. A correct analysis of volume ratios using a different set of equations is presented. Analysis of data produced by SRIM [J.F. Ziegler, J.P. Biersack, U. Littmark, in: The Stopping and Range of Ions in solids, Pergamon, New York, 1985] (Monte Carlo) simulations gives results that are in good agreement with Sigmund's predictions.

  19. The RBE of Fractionated Fast Neutron on Walker 256 Carcinosarcoma with KCCH-Cyclotron

    International Nuclear Information System (INIS)

    Yoo, Seong Yul; Koh, Kyoung Hwan; Cho, Chul Koo; Park, Charn Il; Kang, Wee Saing

    1987-01-01

    For evaluation of biological effect of p+(50.5 MeV) Be neutron beam produced by Korea Cancer Center Hospital(KCCH) cyclotron the RBE had been measured in experimental tumor Walker 256 carcinosarcoma as well as normal tissue, mouse intestine and bone marrow, in single and fractionated irradiation. As pilot study, the RBE had been measured for the mouse jejunal crypt cells in single whole body irradiation of which the result was 2.8. The obtained RBE values of TCD 50 of Walker 256 tumor, bone marrow and intestine in single irradiation were 1.9, 1.9 and 1.5 respectively. In fractionated irradiation, the RBE value of tumor Walker 256 was decreased as increasing of fraction number and increased as increasing of fraction size

  20. Circular orbits in cosmic string and Schwarzschild-AdS spacetime with Fermi-Walker transport

    International Nuclear Information System (INIS)

    Bakke, K.; Furtado, C.; Carvalho, A.M. de

    2009-01-01

    In this paper we discuss the Fermi-Walker transport of vectors along orbits in cosmic string and Schwarzschild-AdS spacetimes. We analyze the influence of acceleration on these holonomies. An effect similar to Thomas precession is observed within the process of Fermi-Walker transport along these circular orbits which are studied in the limit of vanishing cosmological constant in Schwarzschild-AdS case; also we obtain Fermi-Walker transport in a Schwarzschild background. In the case of a Schwarzschild spacetime, we analyze the quantized band holonomy invariance. In the limit of zero acceleration we recover the well-known results for holonomy matrix obtained by parallel transport in all these spacetimes. (orig.)

  1. Exact solution of two interacting run-and-tumble random walkers with finite tumble duration

    International Nuclear Information System (INIS)

    Slowman, A B; Evans, M R; Blythe, R A

    2017-01-01

    We study a model of interacting run-and-tumble random walkers operating under mutual hardcore exclusion on a one-dimensional lattice with periodic boundary conditions. We incorporate a finite, poisson-distributed, tumble duration so that a particle remains stationary whilst tumbling, thus generalising the persistent random walker model. We present the exact solution for the nonequilibrium stationary state of this system in the case of two random walkers. We find this to be characterised by two lengthscales, one arising from the jamming of approaching particles, and the other from one particle moving when the other is tumbling. The first of these lengthscales vanishes in a scaling limit where the continuous-space dynamics is recovered whilst the second remains finite. Thus the nonequilibrium stationary state reveals a rich structure of attractive, jammed and extended pieces. (paper)

  2. Robust Redundant Input Reliable Tracking Control for Omnidirectional Rehabilitative Training Walker

    Directory of Open Access Journals (Sweden)

    Ping Sun

    2014-01-01

    Full Text Available The problem of robust reliable tracking control on the omnidirectional rehabilitative training walker is examined. The new nonlinear redundant input method is proposed when one wheel actuator fault occurs. The aim of the study is to design an asymptotically stable controller that can guarantee the safety of the user and ensure tracking on a training path planned by a physical therapist. The redundant degrees of freedom safety control and the asymptotically zero state detectable concept of the walker are presented, the model of redundant degree is constructed, and the property of center of gravity constant shift is obtained. A controller that can satisfy asymptotic stability is obtained using a common Lyapunov function for admissible uncertainties resulting from an actuator fault. Simulation results confirm the effectiveness of the proposed method and verify that the walker can provide safe sequential motion when one wheel actuator is at fault.

  3. Mary Edwards Walker, M.D.: a feminist physician a century ahead of her time.

    Science.gov (United States)

    Spiegel, A D; Suskind, P B

    1996-06-01

    In her teens, Mary Edwards Walker already wore the "bloomer" outfit began to campaign for reforming the "unhygienic" clothing of women. Assertively, she attended medical school and earned her M.D. degree. Due to prejudice, her practice did not flourish and she moved to Washington to offer her medical services to the Union as the Civil War began. Rebuffed by the male medical bureaucrats, she volunteered her services anyway. Eventually, she was awarded the Congressional Medal of Honor, the only women to ever gain such distinction. After the war, Walker became a journalist, an author of two sensational books, a political lobbyist, a suffrage campaigner, a professional and public lecturer, an ardent dress reformer, a peace activist, a Utopianist and a women's right advocate. Light-years ahead of her times, Dr. Walker was an intelligent, independent, irrepressible and indefatigable proponent for a host of worthy causes.

  4. Anterior or posterior walkers for children with cerebral palsy? A systematic review.

    Science.gov (United States)

    Poole, Marilyn; Simkiss, Doug; Rose, Alice; Li, François-Xavier

    2018-05-01

    To review the literature comparing use of anterior and posterior walkers (PW's) by children with cerebral palsy (CP) to determine which walker type is preferable. Electronic databases were searched using pre-defined terms by two independent reviewers. Reference lists of included studies were hand searched. Studies published between 1985 and 2016 comparing use of anterior and PW's by children with CP were included. All study designs and outcomes were accepted. Risk of bias was assessed using the "Quality assessment standard for a cross-over study". Quality of evidence was evaluated using GRADE. Six studies were analysed. All studies had small sample sizes. A total of 4/6 studies were randomized. A total of 4/6 had high risk of bias. Outcomes included velocity, pelvic tilt, hip flexion, knee flexion, step length, stride length, cadence, double stance time, oxygen cost and participant/parental preference. Velocity, trunk flexion/pelvic tilt, and stability may be improved by using a PW, however, GRADE quality was very low for all outcomes and there was heterogeneity between studies. The majority of participants and parents preferred the PW. Heterogeneity and low quality of existing evidence prevented recommendation of one walker type. Well-designed studies with adequate power are needed to inform clinical recommendations. Implications for rehabilitation Clinical recommendations cannot be made for whether anterior or posterior walkers are preferable for children with cerebral palsy based on the existing evidence. Velocity, trunk flexion/pelvic tilt, and stability may be improved by using a posterior walker. The majority of walking aid users and their parents preferred posterior walkers. Adequately powered studies designed to minimize bias are needed.

  5. Palmistichus elaeisis Delvare & LaSalle (Hymenoptera, Eulophidae: a new parasitoid of Dione juno juno (Cramer (Lepidoptera, Nymphalidae Palmistichus elaeisis Delvare & LaSalle (Hymenoptera, Eulophidae: um novo parasitóide de Dione juno juno (Cramer (Lepidoptera, Nymphalidae

    Directory of Open Access Journals (Sweden)

    Hélcio R. Gil-Santana

    2006-09-01

    Full Text Available Palmistichus elaeisis Delvare & LaSalle, 1993 (Hymenoptera, Eulophidae is recorded as parasitoid of Dione juno juno (Cramer, 1779 (Lepidoptera, Nymphalidae in the State of Rio de Janeiro, Brazil.Palmistichus elaeisis Delvare & LaSalle, 1993 (Hymenoptera, Eulophidae é registrado como parasitóide de Dione juno juno (Cramer, 1779 (Lepidoptera, Nymphalidae, no estado do Rio de Janeiro, Brasil.

  6. Galilean generalized Robertson-Walker spacetimes: A new family of Galilean geometrical models

    Science.gov (United States)

    de la Fuente, Daniel; Rubio, Rafael M.

    2018-02-01

    We introduce a new family of Galilean spacetimes, the Galilean generalized Robertson-Walker spacetimes. This new family is relevant in the context of a generalized Newton-Cartan theory. We study its geometrical structure and analyse the completeness of its inextensible free falling observers. This sort of spacetimes constitutes the local geometric model of a much wider family of spacetimes admitting certain conformal symmetry. Moreover, we find some sufficient geometric conditions which guarantee a global splitting of a Galilean spacetime as a Galilean generalized Robertson-Walker spacetime.

  7. Experimental Studies of Wheelchair and Walker Users Passing Through Doors with Different Opening Force.

    Science.gov (United States)

    Nersveen, Jonny

    2016-01-01

    Users of walkers and users of different categories of wheelchairs tested doors with different opening force, aiming to reveal the limit that these groups of people could manage on an everyday basis. 94.7% of the wheelchair users reported that a door opening force of 30 N was acceptable, while as 92.1% of this group described 40 N as acceptable. Similarly, 100% of the walker users reported that a door opening force of 30 N was acceptable, while as 87,5% of this group described 40 N as acceptable.

  8. Empowering and Assisting Natural Empowering and Assisting Natural Human Mobility: The Simbiosis Walker

    Directory of Open Access Journals (Sweden)

    Anselmo Frizera-Neto

    2011-08-01

    Full Text Available This paper presents the complete development of the Simbiosis Smart Walker. The device is equipped with a set of sensor subsystems to acquire user-machine interaction forces and the temporal evolution of user's feet during gait. The authors present an adaptive filtering technique used for the identification and separation of different components found on the human-machine interaction forces. This technique allowed isolating the components related with the navigational commands and developing a Fuzzy logic controller to guide the device. The Smart Walker was clinically validated at the Spinal Cord Injury Hospital of Toledo - Spain, presenting great acceptability by spinal chord injury patients and clinical staff.

  9. Test pilots 1962 - Armstrong, Walker, Dana, Peterson, McKay, Thompson, Butchart

    Science.gov (United States)

    1962-01-01

    The research pilots at what in 1962 was called the Flight Research Center standing in front of the X-1E. They are (left to right) Neil Armstrong, Joe Walker, Bill Dana, Bruce Peterson, Jack McKay, Milt Thompson, and Stan Butchart. of the group, Armstrong, Walker, Dana, McKay and Thompson all flew the X-15. Bruce Peterson flew the M2-F2 and HL-10 lifting bodies, while Stan Butchart was the B-29 drop plane pilot for many of the D-558-II and X-1 series research aircraft.

  10. 77 FR 67811 - Porter-Walker LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for...

    Science.gov (United States)

    2012-11-14

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ER13-327-000] Porter-Walker LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for Blanket Section 204 Authorization This is a supplemental notice in the above-referenced proceeding of Porter-Walker...

  11. Simulation of the Lower Walker River Basin hydrologic system, west-central Nevada, using PRMS and MODFLOW models

    Science.gov (United States)

    Allander, Kip K.; Niswonger, Richard G.; Jeton, Anne E.

    2014-01-01

    Walker Lake is a terminal lake in west-central Nevada with almost all outflow occurring through evaporation. Diversions from Walker River since the early 1900s have contributed to a substantial reduction in flow entering Walker Lake. As a result, the lake is receding, and salt concentrations have increased to a level in which Oncorhynchus clarkii henshawi (Lahontan Cutthroat trout) are no longer present, and the lake ecosystem is threatened. Consequently, there is a concerted effort to restore the Walker Lake ecosystem and fishery to a level that is more sustainable. However, Walker Lake is interlinked with the lower Walker River and adjacent groundwater system which makes it difficult to understand the full effect of upstream water-management actions on the overall hydrologic system including the lake level, volume, and dissolved-solids concentrations of Walker Lake. To understand the effects of water-management actions on the lower Walker River Basin hydrologic system, a watershed model and groundwater flow model have been developed by the U.S. Geological Survey in cooperation with the Bureau of Reclamation and the National Fish and Wildlife Foundation.

  12. 75 FR 49517 - Notice of Intent To Prepare an Environmental Impact Statement for the Walker Ridge Wind Project...

    Science.gov (United States)

    2010-08-13

    ...] Notice of Intent To Prepare an Environmental Impact Statement for the Walker Ridge Wind Project, Lake and...: You may submit comments related to the Walker Ridge Wind Project by any of the following methods: Web... CONTACT: For further information and/or to have your name added to our mailing list, contact Bethney...

  13. Single locus complementary sex determination in Hymenoptera: an "unintelligent" design?

    Directory of Open Access Journals (Sweden)

    Driessen Gerard

    2006-01-01

    Full Text Available Abstract The haplodiploid sex determining mechanism in Hymenoptera (males are haploid, females are diploid has played an important role in the evolution of this insect order. In Hymenoptera sex is usually determined by a single locus, heterozygotes are female and hemizygotes are male. Under inbreeding, homozygous diploid and sterile males occur which form a genetic burden for a population. We review life history and genetical traits that may overcome the disadvantages of single locus complementary sex determination (sl-CSD. Behavioural adaptations to avoid matings between relatives include active dispersal from natal patches and mating preferences for non-relatives. In non-social species, temporal and spatial segregation of male and female offspring reduces the burden of sl-CSD. In social species, diploid males are produced at the expense of workers and female reproductives. In some social species, diploid males and diploid male producing queens are killed by workers. Diploid male production may have played a role in the evolution or maintenance of polygyny (multiple queens and polyandry (multiple mating. Some forms of thelytoky (parthenogenetic female production increase homozygosity and are therefore incompatible with sl-CSD. We discuss a number of hypothetical adaptations to sl-CSD which should be considered in future studies of this insect order.

  14. A New Species of Vespula, and First Record of Vespa crabro L. (Hymenoptera:Vespidae) from Guatemala, Central America

    Science.gov (United States)

    Vespula akrei Landolt sp. nov. (Hymenoptera:Vespidae; Vespinae) is described from Guatemala. The first record of Vespa crabro L. (Hymenoptera:Vespidae:Vespinae) in Guatemala is given, and Vespula Inexspectata Eck (1994) from Mexico is re-described. We place Vespula akrei sp. nov. in the Vespula vulg...

  15. [Needs, uses, cons-pros, good practices and opportunities about walker in elderly with loss of autonomy].

    Science.gov (United States)

    Mézière, Anthony; Schonheit, Claire; Moreau, Caroline; Baudry, Elodie; Monié, Marguerite; Piette, François; Curtis, Valentine; Pasqui, Viviane

    2015-01-01

    Non-use of the walker may be secondary to an initial inappropriate prescribing, a lack of adequate training, a lack of monitoring and side effects of using. Improving both stability and mobility in users is due to several biomechanical mechanisms. The benefits of walker are: general physiological effects, more confidence, better social life and decrease in the burden of care. The disadvantages of walker are: technical or practical aspects criticized by users, musculoskeletal disorders, delayed reaction time, fall risk and stigma. Few scientific data evaluating the interest of the walker concerning mobility exist, thus recommendations are low grade and are often taken from professional clinical experiences. The choice of technical walking assistance depends on the pathology and biomechanical mechanism. The walker robots are few distributed. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  16. Effect of uphill and downhill walking on walking performance in geriatric patients using a wheeled walker.

    Science.gov (United States)

    Lindemann, Ulrich; Schwenk, Michael; Schmitt, Syn; Weyrich, Michael; Schlicht, Wolfgang; Becker, Clemens

    2017-08-01

    Wheeled walkers are recommended to improve walking performance in older persons and to encourage and assist participation in daily life. Nevertheless, using a wheeled walker can cause serious problems in the natural environment. This study aimed to compare uphill and downhill walking with walking level in geriatric patients using a wheeled walker. Furthermore, we investigated the effect of using a wheeled walker with respect to dual tasking when walking level. A total of 20 geriatric patients (median age 84.5 years) walked 10 m at their habitual pace along a level surface, uphill and downhill, with and without a standard wheeled walker. Gait speed, stride length and cadence were assessed by wearable sensors and the walk ratio was calculated. When using a wheeled walker while walking level the walk ratio improved (0.58 m/[steps/min] versus 0.57 m/[steps/min], p = 0.023) but gait speed decreased (1.07 m/s versus 1.12 m/s, p = 0.020) when compared to not using a wheeled walker. With respect to the walk ratio, uphill and downhill walking with a wheeled walker decreased walking performance when compared to level walking (0.54 m/[steps/min] versus 0.58 m/[steps/min], p = 0.023 and 0.55 m/[steps/min] versus 0.58 m/[steps/min], p = 0.001, respectively). At the same time, gait speed decreased (0.079 m/s versus 1.07 m/s, p walker improved the quality of level walking but the performance of uphill and downhill walking was worse compared to walking level when using a wheeled walker.

  17. Racial Stereotypes and the Art of Kara Walker Stéréotypes raciaux dans l’art de Kara Walker

    Directory of Open Access Journals (Sweden)

    Monika Seidl

    2009-07-01

    Full Text Available L’artiste afro-américaine Kara Walker (1969- travaille principalement sur les silhouettes découpées, forme d’art des XVIIIe et XIXe siècles qui était alors utilisée pour les portraits, les caricatures et la décoration. Un grand nombre de critiques d’art, tout particulièrement Howardena Pindell, accuse Walker de renforcer les stéréotypes raciaux et de ne pas réussir à mettre le présent en relation avec le passé dans son travail. Cet article considère l’aspect humoristique du travail de Walker et défend l’idée que le rire est une pratique spatiale, en tant qu’expérience vécue, qui occupe une partie seulement de l’espace se trouvant entre les stéréotypes raciaux et la vie. Offrir une perspective ludique est une stratégie clé dans un contexte de recherche d’un espace à partir duquel il est possible de critiquer et d’analyser des imaginaires sociaux irréconciliables. La distorsion gênante de Walker se situe dans son insistance à aplanir les corps et donc à leur retirer tout espace, tout en les étalant littéralement en tant que projections sur une surface plane, accentuant de ce fait le coté dramatique du blanc et du noir. A première vue, les silhouettes de Walker semblent perpétuer un code dichotomique de la différence culturelle. Cependant, cet article montre que le troisième espace, celui du rire, exerce une force perturbatrice qui commente la politique de la représentation à partir des stéréotypes eux-mêmes. Cet argument est illustré par son panneau Safety Curtain I qui servit de rideau à l’Opéra de Vienne pendant l’hiver 1998-1999.

  18. The Deep Semantics of Imagery in Alice Walker's The Color Purple ...

    African Journals Online (AJOL)

    Hinged on this theoretical framework, the paper assesses the deep semantics of imagery in Walker's The Color Purple and highlights the salient non-ostensive references of the text and the new world it proposes. The analysis reveals the key to a deeper and broader perception of God, the imperativeness of equality of ...

  19. If the Song Sounds the Same Check for Static: A Reply to Walker and Frimer

    Science.gov (United States)

    Sherblom, Stephen A.

    2009-01-01

    The "care challenge" is shown to be both broader and more successful than Walker and Frimer's (this issue, pp. 53-68) critique allows. The main philosophical and psychological tenets of the care challenge foreshadowed the direction of twenty-first century moral psychology.

  20. The navel orangeworm, Amyelois transtilla (Walker) (Lepidoptera: Pyralidae) discovered in northeastern Mexico feeding on Sapindaceae

    Science.gov (United States)

    Amyelois transitella (Walker) (Lepidoptera: Pyralidae), the navel orangeworm, is an important pest of a wide variety fruits and their seeds. We discovered and report for the first time A. transitella feeding on Sapindaceae in wild populations of U. speciosa (Endl.) in northeastern Mexico. We provid...

  1. The Legal Dimension of RTI--Confusion Confirmed: A Response to Walker and Daves

    Science.gov (United States)

    Zirkel, Perry A.

    2012-01-01

    In this issue of "Learning Disability Quarterly" (LDQ), Professors Daves and Walker reply to my earlier LDQ article on confusion in the cases and commentary about the legal dimension of RTI. In this brief rejoinder, I show that their reply confirms rather than resolves the confusion in their original commentary in 2010. This persistent…

  2. A Linguistic Analysis of Rhetorical Strategies in Selected Narratives of Alice Walker

    Science.gov (United States)

    Matunda, Robert Stephen Mokaya

    2009-01-01

    The objective of this investigation was to analyze rhetorical strategies of Alice Walker in four narratives, namely, "The Color Purple, In Search of Our Mother's Gardens, Possessing the Secret of Joy, and Now Is the Time To Open Your Heart". As such, this study helps to expand the body of investigation relating linguistics to literature and medium…

  3. Epiphanic Awakenings in Raymond Carver's "Cathedral" and Alice Walker's "Everyday Use"

    Science.gov (United States)

    Sadeq, Ala Eddin; Al-Badawi, Mohammed

    2016-01-01

    This paper explores how two short stories from very different backgrounds conclude in a significant epiphany for the characters. Raymond Carver's short story "Cathedral" and Alice Walker's "Everyday Use" are studied to see how the husband in Carver's work is blinder than his visually-impaired overnight guest, and the…

  4. Collateral Damage: Veterans and Domestic Violence in Mari Sandoz's "The Tom-Walker"

    Science.gov (United States)

    Bahr, Kathy

    2010-01-01

    "The Tom-Walker" combines the best of Sandoz's realism with her worst attempts at moralizing. Unable to divine exactly what political configuration right-wing post-World War II sentiments might take, Sandoz nevertheless feared a fascist uprising in this country. Perhaps because these concerns dominated her thoughts at the time, she allowed her…

  5. Bistability and biasing effects in the perception of ambiguous point-light walkers.

    Science.gov (United States)

    Vanrie, Jan; Dekeyser, Mathias; Verfaillie, Karl

    2004-01-01

    The perceptually bistable character of point-light walkers has been examined in three experiments. A point-light figure without explicit depth cues constitutes a perfectly ambiguous stimulus: from all viewpoints, multiple interpretations are possible concerning the depth orientation of the figure. In the first experiment, it is shown that non-lateral views of the walker are indeed interpreted in two orientations, either as facing towards the viewer or as facing away from the viewer, but that the interpretation in which the walker is oriented towards the viewer is reported more frequently. In the second experiment the point-light figure was walking backwards, making the global orientation of the point-light figure opposite to the direction of global motion. The interpretation in which the walker was facing the viewer was again reported more frequently. The robustness of these findings was examined in the final experiment, in which the effects of disambiguating the stimulus by introducing a local depth cue (occlusion) or a more global depth cue (applying perspective projection) were explored.

  6. Precipitation Change and Soil Leaching: Field Results and Simulations from Walker Branch Watershed, Tennessee

    Science.gov (United States)

    D.W. Johnson; P.J. Hanson; D.E. Todd; R.B. Susfalk; Carl C. Trettin

    1998-01-01

    Abstract. To investigate the potential effects of changing precipitation on a deciduous forest ecosystem, an experiment was established on Walker Branch Watershed, Tennessee that modified the amount of throughfall at 4 -33 %. ambient (no change), and +33 % using a system of rain gutters and sprinklers. We hypothesized that the drier treatments would...

  7. Cloning, purification and crystallization of a Walker-type Pyrococcus abyssi ATPase family member

    Energy Technology Data Exchange (ETDEWEB)

    Uhring, Muriel; Bey, Gilbert; Lecompte, Odile; Cavarelli, Jean; Moras, Dino; Poch, Olivier, E-mail: poch@igbmc.u-strasbg.fr [Département de Biologie et Génomiques Structurales, UMR 7104, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP Strasbourg, 1 Rue Laurent Fries, 64404 Illkirch (France)

    2005-10-01

    The Walker-type ATPase PABY2304 of P. abyssi has been cloned, overexpressed, purified and crystallized. X-ray diffraction data from selenomethionine-derivative crystals have been collected to 2.6 Å. The structure has been solved by MAD techniques. Several ATPase proteins play essential roles in the initiation of chromosomal DNA replication in archaea. Walker-type ATPases are defined by their conserved Walker A and B motifs, which are associated with nucleotide binding and ATP hydrolysis. A family of 28 ATPase proteins with non-canonical Walker A sequences has been identified by a bioinformatics study of comparative genomics in Pyrococcus genomes. A high-throughput structural study on P. abyssi has been started in order to establish the structure of these proteins. 16 genes have been cloned and characterized. Six out of the seven soluble constructs were purified in Escherichia coli and one of them, PABY2304, has been crystallized. X-ray diffraction data were collected from selenomethionine-derivative crystals using synchrotron radiation. The crystals belong to the orthorhombic space group C2, with unit-cell parameters a = 79.41, b = 48.63, c = 108.77 Å, and diffract to beyond 2.6 Å resolution.

  8. Motor properties from persistence: a linear molecular walker lacking spatial and temporal asymmetry

    International Nuclear Information System (INIS)

    Zuckermann, Martin J; Forde, Nancy R; Angstmann, Christopher N; Schmitt, Regina; Linke, Heiner; Blab, Gerhard A; Bromley, Elizabeth HC; Curmi, Paul MG

    2015-01-01

    The stepping direction of linear molecular motors is usually defined by a spatial asymmetry of the motor, its track, or both. Here we present a model for a molecular walker that undergoes biased directional motion along a symmetric track in the presence of a temporally symmetric chemical cycle. Instead of using asymmetry, directionality is achieved by persistence. At small load force the walker can take on average thousands of steps in a given direction until it stochastically reverses direction. We discuss a specific experimental implementation of a synthetic motor based on this design and find, using Langevin and Monte Carlo simulations, that a realistic walker can work against load forces on the order of picoNewtons with an efficiency of ∼18%, comparable to that of kinesin. In principle, the walker can be turned into a permanent motor by externally monitoring the walker’s momentary direction of motion, and using feedback to adjust the direction of a load force. We calculate the thermodynamic cost of using feedback to enhance motor performance in terms of the Shannon entropy, and find that it reduces the efficiency of a realistic motor only marginally. We discuss the implications for natural protein motor performance in the context of the strong performance of this design based only on a thermal ratchet. (paper)

  9. Bubble merging in breathing DNA as a vicious walker problem in opposite potentials

    DEFF Research Database (Denmark)

    Pedersen, Jonas Nyvold; Hansen, Mikael Sonne; Novotny, Tomas

    2009-01-01

    on the problem of two vicious walkers in opposite potentials. We also present a discrete master equation approach to the bubble coalescence problem. Numerical evaluation and stochastic simulation of the master equation show excellent agreement with the results from the continuum approach. Given...

  10. Cloning, purification and crystallization of a Walker-type Pyrococcus abyssi ATPase family member

    International Nuclear Information System (INIS)

    Uhring, Muriel; Bey, Gilbert; Lecompte, Odile; Cavarelli, Jean; Moras, Dino; Poch, Olivier

    2005-01-01

    The Walker-type ATPase PABY2304 of P. abyssi has been cloned, overexpressed, purified and crystallized. X-ray diffraction data from selenomethionine-derivative crystals have been collected to 2.6 Å. The structure has been solved by MAD techniques. Several ATPase proteins play essential roles in the initiation of chromosomal DNA replication in archaea. Walker-type ATPases are defined by their conserved Walker A and B motifs, which are associated with nucleotide binding and ATP hydrolysis. A family of 28 ATPase proteins with non-canonical Walker A sequences has been identified by a bioinformatics study of comparative genomics in Pyrococcus genomes. A high-throughput structural study on P. abyssi has been started in order to establish the structure of these proteins. 16 genes have been cloned and characterized. Six out of the seven soluble constructs were purified in Escherichia coli and one of them, PABY2304, has been crystallized. X-ray diffraction data were collected from selenomethionine-derivative crystals using synchrotron radiation. The crystals belong to the orthorhombic space group C2, with unit-cell parameters a = 79.41, b = 48.63, c = 108.77 Å, and diffract to beyond 2.6 Å resolution

  11. Prenatal diagnosis of the Dandy-Walker syndrome by sonography and computed tomography

    International Nuclear Information System (INIS)

    Toelly, E.; Ebner, F.; Oberbauer, R.W.

    1984-01-01

    A case of Dandy-Walker-syndrome is presented, comparing the value of sonography and CT in intrauterine diagnosis. Together with a review of the literature of the subject, pathogenesis, morphology and prognosis in regard to the psychomotoric development are discussed. (orig.) [de

  12. Green's functions for a scalar fields in a class of Robertson-Walker space-times

    International Nuclear Information System (INIS)

    Mankin, Romi; Ainsaar, Ain

    1997-01-01

    The retarded and advanced Green's functions for a massless non conformally-coupled scalar field in a class of Robertson-Walker space-times are calculated analytically. The results are applied to the calculation of the Hadamard fundamental solutions in some special cases. (author)

  13. Sex Differences in Moral Reasoning: Response to Walker's (1984) Conclusion That There Are None.

    Science.gov (United States)

    Baumrind, Diana

    1986-01-01

    Takes issue with Lawrence Walker's literature review on developmental and individual differences in moral reasoning which found no consistent evidence for sex differences in moral development. Argues instead that the source and specific nature of these differences have yet to be established. (HOD)

  14. On Maximal Surfaces in Certain Non-Flat 3-Dimensional Robertson-Walker Spacetimes

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Alfonso, E-mail: aromero@ugr.es [Universidad de Granada, Departamento de Geometria y Topologia (Spain); Rubio, Rafael M., E-mail: rmrubio@uco.es [Universidad de Cordoba, Departamento de Matematicas, Campus de Rabanales (Spain)

    2012-09-15

    An upper bound for the integral, on a geodesic disc, of the squared length of the gradient of a distinguished function on any maximal surface in certain non-flat 3-dimensional Robertson-Walker spacetimes is obtained. As an application, a new proof of a known Calabi-Bernstein's theorem is given.

  15. Experience in the management of Dandy-Walker syndrome in an ...

    African Journals Online (AJOL)

    Dandy-Walker Syndrome (DWS) is a congenital brain malformation involving the cerebellum and the fluid spaces around it. There is atresia of foramenofMagendie and Lushka resulting in a complete absence of the part of the brain located between the two cerebellar hemispheres (cerebellarvermis) and cystic dilatation of ...

  16. Walkers' Perspectives on Nature Management Strategies: Nature Restoration in a National Park

    NARCIS (Netherlands)

    Marwijk, van R.B.M.

    2008-01-01

    Leisure practices and public space, third chapter. Ramona van Marwijk is part of a bigger research projecton time-space behavioural patterns in a landscape where nature development and recreational values are combined. She is interested in what walkers in the Dutch National Park Dwingelderveld think

  17. Trans-sphenoidal encephalocele in association with Dandy-Walker complex and cardiovascular anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Joy, H.M.; Barker, C.S. [Wessex Neurological Centre, Southampton (United Kingdom); Small, J.H. [Dept. of Radiology, Royal Bournemouth Hospital (United Kingdom); Armitage, M. [Bournemouth Diabetes and Endocrine Centre, Royal Bournemouth Hospital (United Kingdom)

    2001-01-01

    We present a case of trans-sphenoidal encephalomeningocele in association with a posterior cranial fossa malformation which fulfils the criteria for the Dandy-Walker complex. Congenital cardiovascular defects were also present. An abnormality of neural crest development may be responsible for the combined occurrence of these anomalies. (orig.)

  18. Deterministic and Probabilistic Serviceability Assessment of Footbridge Vibrations due to a Single Walker Crossing

    Directory of Open Access Journals (Sweden)

    Cristoforo Demartino

    2018-01-01

    Full Text Available This paper presents a numerical study on the deterministic and probabilistic serviceability assessment of footbridge vibrations due to a single walker crossing. The dynamic response of the footbridge is analyzed by means of modal analysis, considering only the first lateral and vertical modes. Single span footbridges with uniform mass distribution are considered, with different values of the span length, natural frequencies, mass, and structural damping and with different support conditions. The load induced by a single walker crossing the footbridge is modeled as a moving sinusoidal force either in the lateral or in the vertical direction. The variability of the characteristics of the load induced by walkers is modeled using probability distributions taken from the literature defining a Standard Population of walkers. Deterministic and probabilistic approaches were adopted to assess the peak response. Based on the results of the simulations, deterministic and probabilistic vibration serviceability assessment methods are proposed, not requiring numerical analyses. Finally, an example of the application of the proposed method to a truss steel footbridge is presented. The results highlight the advantages of the probabilistic procedure in terms of reliability quantification.

  19. Parenchymal neurocutaneous melanosis in association with intraventricular dermoid and Dandy-walker variant: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Joo; Won, Yoo Dong; Kim, Ki Tae; Chang, Eun Deok; Huh, Pil Woo [The Catholic University of Korea, College of Medicine, Uijongbu (Korea, Republic of)

    2006-06-15

    Neurocutaneous melanosis (NCM) is a rare congenital disease that is characterized by the presence of large or multiple congenital melanocytic nevi and melanotic lesions of the central nervous system. We report here on the CT and MR imaging findings of an unusual case of NCM that was associated with intraventricular dermoid and Dandy-Walker malformation.

  20. Spacelike Hypersurfaces in Weighted Generalized Robertson-Walker Space-Times

    Directory of Open Access Journals (Sweden)

    Ximin Liu

    2018-01-01

    Full Text Available Applying generalized maximum principle and weak maximum principle, we obtain several uniqueness results for spacelike hypersurfaces immersed in a weighted generalized Robertson-Walker (GRW space-time under suitable geometric assumptions. Furthermore, we also study the special case when the ambient space is static and provide some results by using Bochner’s formula.

  1. Extraction and radioimmunological detection of parathormone from the hypercalcaemic Walker carcinosarcoma 256 of the rat

    International Nuclear Information System (INIS)

    Schieber, P.

    1978-01-01

    Out of 1.5 kg solid Walker carcionosarcoma 256, 1682 mg extract were obtained by a specific parathormone extraction technique. This extract was analyzed radioimmunologically with a bovine parathormone standard for comparison. The radioimmunological analysis showed a comparable immunoreactivity in tumour extract and bovine parathormone. This can be seen in the small difference in the rise of regression lines. (orig.) [de

  2. Swing-Leg Retraction for Limit Cycle Walkers Improves Disturbance Rejection

    NARCIS (Netherlands)

    Hobbelen, D.G.E.; Wisse, M.

    2008-01-01

    Limit cycle walkers are bipeds that exhibit a stable cyclic gaitwithout requiring local controllability at all times during gait. A well-known example of limit cycle walking is McGeer’s “passive dynamic walking,” but the concept expands to actuated bipeds as involved in this study. One of the

  3. A gait stability investigation into FES-assisted paraplegic walking based on the walker tipping index.

    Science.gov (United States)

    Ming, Dong; Bai, Yanru; Liu, Xiuyun; Qi, Hongzhi; Cheng, Longlong; Wan, Baikun; Hu, Yong; Wong, Yatwa; Luk, Keith D K; Leong, John C Y

    2009-12-01

    The gait outcome measures used in clinical trials of paraplegic locomotor training determine the effectiveness of improved walking function assisted by the functional electrical stimulation (FES) system. Focused on kinematic, kinetic or physiological changes of paraplegic patients, traditional methods cannot quantify the walking stability or identify the unstable factors of gait in real time. Up until now, the published studies on dynamic gait stability for the effective use of FES have been limited. In this paper, the walker tipping index (WTI) was used to analyze and process gait stability in FES-assisted paraplegic walking. The main instrument was a specialized walker dynamometer system based on a multi-channel strain-gauge bridge network fixed on the frame of the walker. This system collected force information for the handle reaction vector between the patient's upper extremities and the walker during the walking process; the information was then converted into walker tipping index data, which is an evaluation indicator of the patient's walking stability. To demonstrate the potential usefulness of WTI in gait analysis, a preliminary clinical trial was conducted with seven paraplegic patients who were undergoing FES-assisted walking training and seven normal control subjects. The gait stability levels were quantified for these patients under different stimulation patterns and controls under normal walking with knee-immobilization through WTI analysis. The results showed that the walking stability in the FES-assisted paraplegic group was worse than that in the control subject group, with the primary concern being in the anterior-posterior plane. This new technique is practical for distinguishing useful gait information from the viewpoint of stability, and may be further applied in FES-assisted paraplegic walking rehabilitation.

  4. Variability in energy cost and walking gait during race walking in competitive race walkers.

    Science.gov (United States)

    Brisswalter, J; Fougeron, B; Legros, P

    1998-09-01

    The aim of this study was to examine the variability of energy cost (Cw) and race walking gait after a 3-h walk at the competition pace in race walkers of the same performance level. Nine competitive race walkers were studied. In the same week, after a first test of VO2max determination, each subject completed two submaximal treadmill walks (6 min length, 0% grade, 12 km X h(-1) speed) before and after a 3-h overground test completed at the individual competition speed of the race walker. During the two submaximal tests, subjects were filmed between the 2nd and the 4th min, and physiological parameters were recorded between the 4th and the 6th min. Results showed two trends. On the one hand, we observed a significant and systematic increase in energy cost of walking (mean deltaCw = 8.4%), whereas no variation in the gait kinematics prescribed by the rules of race walking was recorded. On the other hand, this increase in metabolic energy demand was accompanied by variations of different magnitude and direction of stride length, of the excursion of the heel and of the maximal ankle flexion at toe-off among the race walkers. These results indicated that competitive race walkers are able to maintain their walking gait with exercise duration apart from a systematic increase in energy cost. Moreover, in this form of locomotion the effect of fatigue on the gait variability seems to be an individual function of the race walk constraints and the constraints of the performer.

  5. A gait stability investigation into FES-assisted paraplegic walking based on the walker tipping index

    Science.gov (United States)

    Ming, Dong; Bai, Yanru; Liu, Xiuyun; Qi, Hongzhi; Cheng, Longlong; Wan, Baikun; Hu, Yong; Wong, Yatwa; Luk, Keith D. K.; Leong, John C. Y.

    2009-12-01

    The gait outcome measures used in clinical trials of paraplegic locomotor training determine the effectiveness of improved walking function assisted by the functional electrical stimulation (FES) system. Focused on kinematic, kinetic or physiological changes of paraplegic patients, traditional methods cannot quantify the walking stability or identify the unstable factors of gait in real time. Up until now, the published studies on dynamic gait stability for the effective use of FES have been limited. In this paper, the walker tipping index (WTI) was used to analyze and process gait stability in FES-assisted paraplegic walking. The main instrument was a specialized walker dynamometer system based on a multi-channel strain-gauge bridge network fixed on the frame of the walker. This system collected force information for the handle reaction vector between the patient's upper extremities and the walker during the walking process; the information was then converted into walker tipping index data, which is an evaluation indicator of the patient's walking stability. To demonstrate the potential usefulness of WTI in gait analysis, a preliminary clinical trial was conducted with seven paraplegic patients who were undergoing FES-assisted walking training and seven normal control subjects. The gait stability levels were quantified for these patients under different stimulation patterns and controls under normal walking with knee-immobilization through WTI analysis. The results showed that the walking stability in the FES-assisted paraplegic group was worse than that in the control subject group, with the primary concern being in the anterior-posterior plane. This new technique is practical for distinguishing useful gait information from the viewpoint of stability, and may be further applied in FES-assisted paraplegic walking rehabilitation.

  6. Ground reaction force and 3D biomechanical characteristics of walking in short-leg walkers.

    Science.gov (United States)

    Zhang, Songning; Clowers, Kurt G; Powell, Douglas

    2006-12-01

    Short-leg walking boots offer several advantages over traditional casts. However, their effects on ground reaction forces (GRF) and three-dimensional (3D) biomechanics are not fully understood. The purpose of the study was to examine 3D lower extremity kinematics and joint dynamics during walking in two different short-leg walking boots. Eleven (five females and six males) healthy subjects performed five level walking trials in each of three conditions: two testing boot conditions, Gait Walker (DeRoyal Industries, Inc.) and Equalizer (Royce Medical Co.), and one pair of laboratory shoes (Noveto, Adidas). A force platform and a 6-camera Vicon motion analysis system were used to collect GRFs and 3D kinematic data during the testing session. A one-way repeated measures analysis of variance (ANOVA) was used to evaluate selected kinematic, GRF, and joint kinetic variables (p<0.05). The results revealed that both short-leg walking boots were effective in minimizing ankle eversion and hip adduction. Neither walker increased the bimodal vertical GRF peaks typically observed in normal walking. However, they did impose a small initial peak (<1BW) earlier in the stance phase. The Gait Walker also exhibited a slightly increased vertical GRF during midstance. These characteristics may be related to the sole materials/design, the restriction of ankle movements, and/or the elevated heel heights of the tested walkers. Both walkers appeared to increase the demand on the knee extensors while they decreased the demand of the knee and hip abductors based on the joint kinetic results.

  7. Extraction of user's navigation commands from upper body force interaction in walker assisted gait

    Directory of Open Access Journals (Sweden)

    Pons José L

    2010-08-01

    Full Text Available Abstract Background The advances in technology make possible the incorporation of sensors and actuators in rollators, building safer robots and extending the use of walkers to a more diverse population. This paper presents a new method for the extraction of navigation related components from upper-body force interaction data in walker assisted gait. A filtering architecture is designed to cancel: (i the high-frequency noise caused by vibrations on the walker's structure due to irregularities on the terrain or walker's wheels and (ii the cadence related force components caused by user's trunk oscillations during gait. As a result, a third component related to user's navigation commands is distinguished. Results For the cancelation of high-frequency noise, a Benedict-Bordner g-h filter was designed presenting very low values for Kinematic Tracking Error ((2.035 ± 0.358·10-2 kgf and delay ((1.897 ± 0.3697·101ms. A Fourier Linear Combiner filtering architecture was implemented for the adaptive attenuation of about 80% of the cadence related components' energy from force data. This was done without compromising the information contained in the frequencies close to such notch filters. Conclusions The presented methodology offers an effective cancelation of the undesired components from force data, allowing the system to extract in real-time voluntary user's navigation commands. Based on this real-time identification of voluntary user's commands, a classical approach to the control architecture of the robotic walker is being developed, in order to obtain stable and safe user assisted locomotion.

  8. KEANEKARAGAMAN HYMENOPTERA PARASITOID PADA PERKEBUNAN KELAPA SAWIT PTPN VIII CINDALI, BOGOR

    Directory of Open Access Journals (Sweden)

    Ichsan Luqmana Indra Putra

    2016-09-01

    Full Text Available Diversity of parasitic Hymenoptera in PTPN VIII oil palm plantation Cindali, Bogor. One group of important natural enemies in oil palm plantation is parasitic Hymenoptera. The purpose of this research is to know the diversity and fluctuation of parasitic Hymenoptera PTPN VIII Cindali oil palm plantation. This research was conducted in 6 blocks of oil palm in September 2014 – June 2015. There were 5 plots in every observation blocks 39.2 x 39.2 m in size, and used direct and indirect method. Direct method done by 5 plants in every plots was taken randomized to observed and taken the herbivore insects to reared until the parasitic Hymenoptera came out. Observation of cover crops conducted by 3 subplots determined diagonally in every plots 9.8 x 9.8 m in size and herbivore insects was observed and collected. Indirect methods used sweep net and yellow pan trap. The result of this research, 26 parasitic Hymenoptera families was found, with the Braconidae was the most morphospecies found and the most individual amount was Scelionidae. The abundance of parasitoid in every month fluctuated.

  9. Dataset reporting the perceiver identification rates of basic emotions expressed by male, female and ambiguous gendered walkers in full-light, point-light and synthetically modelled point-light walkers.

    Science.gov (United States)

    Halovic, Shaun; Kroos, Christian

    2017-12-01

    This data set describes the experimental data collected and reported in the research article "Walking my way? Walker gender and display format confounds the perception of specific emotions" (Halovic and Kroos, in press) [1]. The data set represent perceiver identification rates for different emotions (happiness, sadness, anger, fear and neutral), as displayed by full-light, point-light and synthetic point-light walkers. The perceiver identification scores have been transformed into H t rates, which represent proportions/percentages of correct identifications above what would be expected by chance. This data set also provides H t rates separately for male, female and ambiguously gendered walkers.

  10. Influence of an infant walker on onset and quality of walking pattern of locomotion:an electromyographic investigation.

    Science.gov (United States)

    Kauffman, I B; Ridenour, M

    1977-12-01

    Acquisition of bipedal locomotor skill in human infants was studied electromyographically with regard to the deprivation or enrichment behavior resulting from the frequent and regular use of an infant walker. Subjects were six sets of male, fraternal twins. One randomly selected sibling from each set underwent a training program, commencing at the age of 300 days, spending a total of 2 hr. per day in a walker. Siblings not included in this group were subjected to no special training. EMG recordings were taken of all subjects at specified intervals in order to establish a model of the typical motor pattern at various stages of skill development. These data were then contrasted with EMG data similarly obtained from the walker-trained subjects. Use of an infant walker modified the mechanics of the infant's locomotion in a number of important ways. It was shown that use of the walker enables an infant to commit substantial mechanical errors yet succeed in bipedal locomotion. Inasmuch as the mechanics of walker-assisted and non-assisted bipedal locomotion are dissimilar in so many important ways, positive transfer from walker-training appears questionable.

  11. On the identity of Melipona torrida Friese (Hymenoptera, Apidae

    Directory of Open Access Journals (Sweden)

    Gabriel A. R. Melo

    2013-09-01

    Full Text Available On the identity of Melipona torrida Friese (Hymenoptera, Apidae. Melipona marginata var. torrida Friese, 1916, described from three workers putatively collected in Costa Rica, never had its identity properly recognized. Since its original description, no additional specimens have ever been collected in Costa Rica. It is argued here that Melipona torrida was based on mislabeled specimens and corresponds to Melipona marginata obscurior Moure, 1971, a form known only from southern Brazil, Argentina and Paraguay. A lectotype is designated for Melipona torrida and notes on the type material of Melipona marginata obscurior are provided. Other known examples of species described from mislabeled specimens in Friese's Zur Bienenfauna von Costa Rica are discussed. It is pointed out that additional names proposed in this work, based on material from Costa Rica, might turn out to correspond to South American taxa. Also, the date of publication of this Friese's paper is discussed.

  12. Cytogenetic characterization of Partamona cupira (Hymenoptera, Apidae by fluorochromes

    Directory of Open Access Journals (Sweden)

    Jefferson de Brito Marthe

    2010-01-01

    Full Text Available Four colonies of the stingless bee Partamona cupira (Hymenoptera: Apidae were cytogenetically analyzed using conventional staining and the fluorochromes CMA3 e DAPI. The females have 2n = 34 chromosomes (2K=32+2. Some females, however, presented an additional large B acrocentric chromosome, to a total of 2n = 35. Chromosome B and the chromosomal pairs 2, 9 and 10 showed CMA3+ bands, indicating an excess of CG base-pairs. A clear association was verified between the P. helleri B chromosome SCAR marker and the presence of a B chromosome in P. cupira. The data obtained suggests that B chromosomes in P. helleri and P. cupira share a common origin.

  13. ABO blood groups, Rhesus factor, and anaphylactic reactions due to Hymenoptera stings.

    Science.gov (United States)

    Pałgan, Krzysztof; Bartuzi, Zbigniew; Chrzaniecka, Elżbieta

    2017-09-21

    Numerous publications indicate that the prevalence of some infectious, neoplastic and immunological diseases are associated with ABO blood groups. The aim of this study was to verify whether ABO and Rh blood groups are associated with severe anaphylactic reactions after Hymenoptera stings. A study was undertaken of 71,441 Caucasian subjects living in the same geographic area. The study group included 353 patients with diagnosed systemic anaphylaxis to Hymenoptera venom. Control group included 71,088 healthy blood donors. Frequencies of ABO and Rhesus groups in the study and control groups were compared using univariate and multivariate analyses. No statistically significant interactions were observed between the ABO blood group and anaphylactic reactions to Hymenoptera.

  14. Apomictic parthenogenesis in a parasitoid wasp Meteorus pulchricornis, uncommon in the haplodiploid order Hymenoptera.

    Science.gov (United States)

    Tsutsui, Y; Maeto, K; Hamaguchi, K; Isaki, Y; Takami, Y; Naito, T; Miura, K

    2014-06-01

    Although apomixis is the most common form of parthenogenesis in diplodiploid arthropods, it is uncommon in the haplodiploid insect order Hymenoptera. We found a new type of spontaneous apomixis in the Hymenoptera, completely lacking meiosis and the expulsion of polar bodies in egg maturation division, on the thelytokous strain of a parasitoid wasp Meteorus pulchricornis (Wesmael) (Braconidae, Euphorinae) on pest lepidopteran larvae Spodoptera litura (Fabricius) (Noctuidae). The absence of the meiotic process was consistent with a non-segregation pattern in the offspring of heterozygous females, and no positive evidence was obtained for the induction of thelytoky by any bacterial symbionts. We discuss the conditions that enable the occurrence of such rare cases of apomictic thelytoky in the Hymenoptera, suggesting the significance of fixed heterosis caused by hybridization or polyploidization, symbiosis with bacterial agents, and occasional sex. Our finding will encourage further genetic studies on parasitoid wasps to use asexual lines more wisely for biological control.

  15. A new scenario of bioprospecting of Hymenoptera venoms through proteomic approach

    Directory of Open Access Journals (Sweden)

    LD Santos

    2011-01-01

    Full Text Available Venoms represent a huge and essentially unexplored reservoir of bioactive components that may cure diseases that do not respond to currently available therapies. This review select advances reported in the literature from 2000 to the present about the new scenario of Hymenoptera venom composition. On account of new technologies in the proteomic approach, which presents high resolution and sensitivity, the combination of developments in new instruments, fragmentation methods, strategic analysis, and mass spectrometry have become indispensable tools for interrogation of protein expression, molecule interaction, and post- translational modifications. Thus, the biochemical characterization of Hymenoptera venom has become a major subject of research in the area of allergy and immunology, in which proteomics has been an excellent alternative to assist the development of more specific extracts for diagnosis and treatment of hypersensitive patients to Hymenoptera venoms.

  16. Experimental model of ultrasound thermotherapy in rats inoculated with Walker-236 tumor Modelo experimental de termoterapia ultrassônica em ratos inoculados com tumor de Walker-236

    Directory of Open Access Journals (Sweden)

    José Antonio Carlos Otaviano David Morano

    2011-01-01

    Full Text Available PURPOSE: To develop a model to evaluate the effects of focal pulsed ultrasound (US waves as a source of heat for treatment of murine subcutaneous implanted Walker tumor. METHODS: An experimental, controlled, comparative study was conducted. Twenty male Wistar rats (160-300 g randomized in 2 equal groups (G-1: Control and G-2: Hyperthermia were inoculated with Walker-256 carcinosarcoma tumor. After 5 days G-2 rats were submitted to 45ºC hyperthermia. Heat was delivered directly to the tumor by an ultrasound (US equipment (3 MHz frequency, 1,5W/cm³. Tumor temperature reached 45º C in 3 minutes and was maintained at this level for 5 minutes. Tumor volume was measured on days 5, 8, 11, 14 e 17 post inoculation in both groups. Unpaired t-test was used for comparison. POBJETIVO: Desenvolver um modelo para avaliar os efeitos do ultra-som focal pulsado como fonte de calor para o tratamento de tumores de Walker subcutâneos implantados em ratos. MÉTODOS: Um estudo experimental, controlado, comparativo foi realizado. Vinte ratos Wistar machos (160-300 g divididos em dois grupos (G-1: Controle e G-2: hipertermia foram inoculados com tumor de Walker carcinossarcoma-256. Após cinco dias os ratos do grupo G-2 ratos foram submetidos a hipertermia (45ºC. O calor foi aplicado diretamente no tumor por um equipamento de ultrassonografia (3 MHz, 1,5 W/cm³. A temperatura no tumor atingiu 45ºC em 3 minutos e foi mantida nesse nível por 5 minutos. O volume do tumor foi medido nos dias 5, 8, 11, 14 e 17 após a inoculação, em ambos os grupos. Teste t não pareado foi utilizado para comparação. P <0,05 foi considerado significante. RESULTADOS: O volume do tumor foi significativamente maior no 5º dia e diminuiu nos dias 11, 14 e 17 nos ratos tratados. Animais submetidos à hipertermia sobreviveram mais tempo que os animais do grupo controle. No 29º dia após a inoculação do tumor, 40% dos ratos do grupo controle e 77,78% dos ratos tratados com

  17. Espécies novas de Trigonisca Moure (Hymenoptera, Apidae, Apinae New species of Trigonisca Moure (Hymenoptera, Apidae, Apinae

    Directory of Open Access Journals (Sweden)

    Patrícia Maia Correia de Albuquerque

    2007-01-01

    Full Text Available Algumas espécies novas de Meliponini do gênero Trigonisca Moure, 1950 (Hymenoptera, Apidae, Apinae do Brasil e Panamá são descritas: T. roubiki sp. nov. (Panamá, T. variegatifrons sp. nov. (Brasil: RO, PA, MT, T. vitrifrons sp. nov. (Brasil: AM, PA, T. unidentata sp. nov. (Brasil: AM, T. meridionalis sp. nov. (Brasil: PA, MA, MT, MG, SP, T. bidentata sp. nov. (Brasil: RO, T. extrema sp. nov. (Brasil: AM e T. hirticornis sp. nov. (Brasil: RO, PA; e são apresentados novos registros geográficos de T. flavicans (Moure, 1950, T. intermedia Moure, 1989, T. dobzhanskyi (Moure, 1950, T. ceophloei (Schwarz, 1938, T. nataliae (Moure, 1950 e T. pediculana (Fabricius, 1804 e uma chave para identificação das espécies.Some new Meliponini species of the genus Trigonisca Moure, 1950 (Hymenoptera, Apidae, Apinae from Brazil and Panamá are described: T. roubiki sp. nov. (Panamá, T. variegatifrons sp. nov. (Brazil: RO, PA, MT, T. vitrifrons sp. nov. (Brazil: AM, PA, T. unidentata sp. nov. (Brazil: AM, T. meridionalis sp. nov. (Brazil: PA, MA, MT, MG, SP, T. bidentata sp. nov. (Brazil: RO, T. extrema sp. nov. (Brazil: AM and T. hirticornis sp. nov. (Brazil: RO, PA; additional geographic records from T. flavicans (Moure, 1950, T. intermedia Moure, 1989, T. dobzhanskyi (Moure, 1950, T. ceophloei (Schwarz, 1938, T. nataliae (Moure, 1950 and T. pediculana (Fabricius, 1804 and an identification key for species are presented.

  18. Epidemiology, diagnosis, and treatment of Hymenoptera venom allergy in mastocytosis patients.

    Science.gov (United States)

    Niedoszytko, Marek; Bonadonna, Patrizia; Oude Elberink, Joanne N G; Golden, David B K

    2014-05-01

    Hymenoptera venom allergy is a typical IgE-mediated reaction caused by sensitization to 1 or more allergens of the venom, and accounts for 1.5% to 34% of all cases of anaphylaxis. Patients suffering from mastocytosis are more susceptible to the anaphylactic reactions to an insect sting. This article aims to answer the most important clinical questions raised by the diagnosis and treatment of insect venom allergy in mastocytosis patients. Total avoidance of Hymenoptera is not feasible, and there is no preventive pharmacologic treatment available, although venom immunotherapy reduces the risk of subsequent systemic reactions. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Separation of massive field equation of arbitrary spin in Robertson-Walker space-time

    International Nuclear Information System (INIS)

    Zecca, A.

    2006-01-01

    The massive spin-(3/2) field equation is explicitly integrated in the Robertson-Walker space-time by the Newman Penrose formalism. The solution is obtained by extending a separation procedure previously used to solve the spin-1 equation. The separated time dependence results in two coupled equations depending on the cosmological background evolution. The separated angular equations are explicitly integrated and the eigenvalues determined. The separated radial equations are integrated in the flat space-time case. The separation method of solution is then generalized, by induction, to prove the main result, that is the separability of the massive field equations of arbitrary spin in the Robertson-Walker space-time

  20. Hidden marker position estimation during sit-to-stand with walker.

    Science.gov (United States)

    Yoon, Sang Ho; Jun, Hong Gul; Dan, Byung Ju; Jo, Byeong Rim; Min, Byung Hoon

    2012-01-01

    Motion capture analysis of sit-to-stand task with assistive device is hard to achieve due to obstruction on reflective makers. Previously developed robotic system, Smart Mobile Walker, is used as an assistive device to perform motion capture analysis in sit-to-stand task. All lower limb markers except hip markers are invisible through whole session. The link-segment and regression method is applied to estimate the marker position during sit-to-stand. Applying a new method, the lost marker positions are restored and the biomechanical evaluation of the sit-to-stand movement with a Smart Mobile Walker could be carried out. The accuracy of the marker position estimation is verified with normal sit-to-stand data from more than 30 clinical trials. Moreover, further research on improving the link segment and regression method is addressed.

  1. Massive bosons interacting with gravity: No standard solutions in Robertson-Walker space-time

    International Nuclear Information System (INIS)

    Zecca, A.

    2009-01-01

    The problem of the interaction of boson and gravitational field is formulated in the Robertson-Walker space-time. It consist the simultaneous solution of the boson and of the Einstein field equation whose source is the energy momentum tensor of the boson field. By direct verification it is shown that the problem does not admit solutions in the class of massive standard solutions, previously determined, of the boson field equation. Also there cannot be solutions, in case of massive interacting boson, that are superpositions of standard solutions. The case of massless boson field is left open. The result is essentially due to the very special form of the Einstein tensor in Robertson-Walker metric.

  2. Pedestrian Dharma: Slowness and Seeing in Tsai Ming-Liang’s Walker

    Directory of Open Access Journals (Sweden)

    Teng-Kuan Ng

    2018-06-01

    Full Text Available This paper studies the ways that Walker, a short film by the Malaysian-Taiwanese auteur Tsai Ming-Liang, visualizes the relationship between Buddhism and modernity. Via detailed film analysis as well as attention to sources in premodern Buddhist traditions, this paper argues that its filmic performance of Zen walking meditation serves two functions: To present slowness and simplicity as prophetic counterpoints against the dizzying excesses of the contemporary metropolis; and to offer contemplative attentiveness as a therapeutic resource for life in the modern world. By instantiating and cultivating critical shifts in viewerly perspective in the manner of Buddhist ritual practice, Walker invites us to envision how a place of frenetic distraction or pedestrian mundaneness might be transfigured into a site of beauty, wonder, and liberation.

  3. Decoherence induced by a chaotic enviroment: A quantum walker with a complex coin

    International Nuclear Information System (INIS)

    Ermann, Leonardo; Paz, Juan Pablo; Saraceno, Marcos

    2006-01-01

    We study the differences between the processes of decoherence induced by chaotic and regular environments. For this we analyze a family of simple models that contain both regular and chaotic environments. In all cases the system of interest is a ''quantum walker,'' i.e., a quantum particle that can move on a lattice with a finite number of sites. The walker interacts with an environment which has a D-dimensional Hilbert space. The results we obtain suggest that regular and chaotic environments are not distinguishable from each other in a (short) time scale t*, which scales with the dimensionality of the environment as t*∝log 2 (D). However, chaotic environments continue to be effective over exponentially longer time scales while regular environments tend to reach saturation much sooner. We present both numerical and analytical results supporting this conclusion. The family of chaotic evolutions we consider includes the so-called quantum multibaker map as a particular case

  4. The Dirac equation and the normalization of its solutions in a closed Friedmann- Robertson-Walker universe

    Energy Technology Data Exchange (ETDEWEB)

    Finster, Felix [NWF I-Mathematik, Universitaet Regensburg, D-93040 Regensburg (Germany); Reintjes, Moritz, E-mail: Felix.Finster@mathematik.uni-regensburg.d, E-mail: moritz@math.ucdavis.ed [Mathematics Department, University of California, Davis, CA 95616 (United States)

    2009-05-21

    We set up the Dirac equation in a Friedmann-Robertson-Walker geometry and separate the spatial and time variables. In the case of a closed universe, the spatial dependence is solved explicitly, giving rise to a discrete set of solutions. We compute the probability integral and analyze a spacetime normalization integral. This analysis allows us to introduce the fermionic projector in a closed Friedmann-Robertson-Walker geometry and to specify its global normalization as well as its local form.

  5. The Dirac equation and the normalization of its solutions in a closed Friedmann- Robertson-Walker universe

    International Nuclear Information System (INIS)

    Finster, Felix; Reintjes, Moritz

    2009-01-01

    We set up the Dirac equation in a Friedmann-Robertson-Walker geometry and separate the spatial and time variables. In the case of a closed universe, the spatial dependence is solved explicitly, giving rise to a discrete set of solutions. We compute the probability integral and analyze a spacetime normalization integral. This analysis allows us to introduce the fermionic projector in a closed Friedmann-Robertson-Walker geometry and to specify its global normalization as well as its local form.

  6. Contribution of radiosensitivity study for Walker 256 tumor in rats. Association of early immunization with action of ionized radiation

    International Nuclear Information System (INIS)

    Sakate, A.T.Y.

    1979-01-01

    The suspension of tumoral cells from Walker 256 were irradiated with doses of 2.500, 4.500, 5.000, 5.500 and 7.500 rad for determining the attenuation dose. The suspension of inactives tumoral cells were injected in rats for verifying the immunized effects in relation of active Walker tumor. After be certified the growth of tumor, the rats were irradiated with cobalt 60 and was verified the decrease of tumor. (author)

  7. Computation of Partially Invariant Solutions for the Einstein Walker Manifolds' Identifying Equations

    OpenAIRE

    Nadjafikhah, Mehdi; Jafari, Mehdi

    2014-01-01

    In this paper, partially invariant solutions (PISs) method is applied in order to obtain new four-dimensional Einstein Walker manifolds. This method is based on subgroup classification for the symmetry group of partial differential equations (PDEs) and can be regarded as the generalization of the similarity reduction method. For this purpose, those cases of PISs which have the defect structure delta=1 and are resulted from two-dimensional subalgebras are considered in the present paper. Also ...

  8. Women in History--Madame C. J. Walker 1867-1919

    Science.gov (United States)

    Huber, Germaine W.

    2009-01-01

    This article profiles Madame C. J. Walker. Sarah Breedlove was born on December 23, 1867, the fifth of six children of Owen and Minerva Breedlove. Sarah was the first of the Breedlove children to be born after the end of slavery. Her parents died when she was six or seven years of age. At age fourteen she married Moses McWilliams, who also died in…

  9. Quantum field theory in flat Robertson-Walker space-time functional Schrodinger picture

    International Nuclear Information System (INIS)

    Pi, S.Y.

    1990-01-01

    Quantum field theory in Robertson-Walker space-time is intrinsically time-dependent and the functional Schrodinger picture provides a useful description. This paper discusses free and self-interacting bosonic quantum field theories: Schrodinger picture quantization, time-dependent Gaussian approximations based on variational principles describing time evolution of pure and mixed states, and renormalizability of the Schrodinger picture. The technique introduced can be used to study various dynamical questions in early universe processes

  10. ARG-walker: inference of individual specific strengths of meiotic recombination hotspots by population genomics analysis.

    Science.gov (United States)

    Chen, Hao; Yang, Peng; Guo, Jing; Kwoh, Chee Keong; Przytycka, Teresa M; Zheng, Jie

    2015-01-01

    Meiotic recombination hotspots play important roles in various aspects of genomics, but the underlying mechanisms for regulating the locations and strengths of recombination hotspots are not yet fully revealed. Most existing algorithms for estimating recombination rates from sequence polymorphism data can only output average recombination rates of a population, although there is evidence for the heterogeneity in recombination rates among individuals. For genome-wide association studies (GWAS) of recombination hotspots, an efficient algorithm that estimates the individualized strengths of recombination hotspots is highly desirable. In this work, we propose a novel graph mining algorithm named ARG-walker, based on random walks on ancestral recombination graphs (ARG), to estimate individual-specific recombination hotspot strengths. Extensive simulations demonstrate that ARG-walker is able to distinguish the hot allele of a recombination hotspot from the cold allele. Integrated with output of ARG-walker, we performed GWAS on the phased haplotype data of the 22 autosome chromosomes of the HapMap Asian population samples of Chinese and Japanese (JPT+CHB). Significant cis-regulatory signals have been detected, which is corroborated by the enrichment of the well-known 13-mer motif CCNCCNTNNCCNC of PRDM9 protein. Moreover, two new DNA motifs have been identified in the flanking regions of the significantly associated SNPs (single nucleotide polymorphisms), which are likely to be new cis-regulatory elements of meiotic recombination hotspots of the human genome. Our results on both simulated and real data suggest that ARG-walker is a promising new method for estimating the individual recombination variations. In the future, it could be used to uncover the mechanisms of recombination regulation and human diseases related with recombination hotspots.

  11. Effects Of Walker 256 Carcinoma On Metabolic Alterations During The Evolution Of Pregnancy.

    OpenAIRE

    Cintra-Gomes M.C.; Cury L.; Parreira M.R.; Elias C.F.; Areas M.A.

    1990-01-01

    The control of pregnant cancer patients is difficult because it involves both mother and fetus, and the metabolic alterations in the cancer host induce a massive mobilization of nutrients diverted to the neoplastic cells. The purpose of the present study was to determine the evolution of the Walker 256 carcinoma in pregnant rats and its consequences on fetal development. The results showed that the tumors displayed a very rapid rate of growth and induced a reduction in fetal weights in the pr...

  12. DO INFANTS USING BABY WALKERS SUFFER DEVELOPMENTAL DELAYS IN ACQUISITION OF MOTOR SKILLS?

    OpenAIRE

    A. Talebian; A. Honarpishe; A. Taghavi; E. Fakharian; M. Parsa; GA. Mousavi

    2008-01-01

     AbstractObjectiveDevelopment is a complex process, completed over a specific period of time, through the maturation of the nervous system. It is affected by genetic, ethnic, nutritional, social, and economic factors; one of the environmental factors affecting the acquisition of motor skills in infants is the use of baby walkers. Since this device is very commonly used for infants in our country, we conducted this study to evaluate its effects on the acquisition of motor skills in this age gr...

  13. Dandy Walker Syndrome with Unusual Associated Findings in a Fetal Autopsy Study

    OpenAIRE

    Surekha U Arakeri; Himanshu Mulay

    2015-01-01

    Dandy Walker Syndrome (DWS) is a congenital brain malformation characterized by hypoplasia or absence of cerebellar vermis, cystic dilatation of fourth ventricle and hydrocephalus. It is frequently associated with other congenital anomalies. Associated central nervous system anomalies such as agenesis of corpus callosum and vermis are associated with poor prognosis. Association of DWS with congenital absence of spleen is life threatening condition and has been reported...

  14. Effects of aquatic walking exercise using a walker in a chronic stroke patient

    OpenAIRE

    Matsuda, Tadashi; Akezaki, Yoshiteru

    2017-01-01

    [Purpose] The aim of this study was to examine the usefulness of aquatic walking exercise using a walker for chronic stroke patients. We also examined the psychological effects on the study subject and the primary caregiver before and after aquatic walking exercise. [Subject and Methods] The subject was a 60-year-old male with bilateral paralysis after a cerebrovascular accident. The Fugl-Meyer Assessment (FMA) total score was 116 on the right and 115 on the left. The intervention combined aq...

  15. Solutions to the maximal spacelike hypersurface equation in generalized Robertson-Walker spacetimes

    Directory of Open Access Journals (Sweden)

    Henrique F. de Lima

    2018-03-01

    Full Text Available We apply some generalized maximum principles for establishing uniqueness and nonexistence results concerning maximal spacelike hypersurfaces immersed in a generalized Robertson-Walker (GRW spacetime, which is supposed to obey the so-called timelike convergence condition (TCC. As application, we study the uniqueness and nonexistence of entire solutions of a suitable maximal spacelike hypersurface equation in GRW spacetimes obeying the TCC.

  16. Quantum field theory in flat Robertson-Walker space-time functional Schroedinger picture

    International Nuclear Information System (INIS)

    Pi, S.Y.

    1989-01-01

    Quantum field theory in Robertson-Walker space-time is intrinsically time-dependent and the functional Schroedinger picture provides a useful description. We discuss free and self-interacting bosonic quantum field theories: Schroedinger picture quantization, time-dependent Gaussian approximations based on variational principles describing time evolution of pure and mixed states, and renormalizability of the Schroedinger picture. The techniques introduced can be used to study various dynamical questions in early universe processes. (author)

  17. THE PARASITOID Anastatus sp. (EUPELMIDAE-HYMENOPTERA ACTION ON Dirphia rosacordis WALKER, 1855 (SATURNIIDAE-LEPIDOPTERA EGGS IN ”PEQUI” (Caryocar brasiliense CAMBESS AÇÃO DO PARASITÓIDE Anastatus sp. (EUPELMIDAE - HYMENOPTERA EM OVOS DE Dirphia rosacordis WALKER, 1855 (LEPIDOPTERA - SATURNIIDAE EM PEQUIZEIRO (Caryocar brasiliense CAMBESS

    Directory of Open Access Journals (Sweden)

    Antônio Henrique Garcia

    2007-09-01

    Full Text Available

    The action of parasitoid Anastatus sp. on eggs of D. rosacordis, common for defoliating “pequizeiro” (Caryocar brasiliense Cambess, was studied on eggs collected in the field and eggs obtained in laboratory. Eggs were collected in Hidrolândia, Senador Canedo and Goiânia, Goiás, Brazil. In these regions, D. rosacordis shows two generations: September and December. To obtain eggs, a D. rosacordis colony was maintained on pequi leaves over the egg mass obtained in the laboratory and kept under controlled temperature, relative humidity and photoperiod. Among 1,346 eggs obtained in laboratory conditions, 44.3% were parasitized, 40.2% were viable and 15.4 % were not viable. From 697 eggs collected in the field, 25.5% were parasitized, 58.9% were viable and 15.6% were not viable. Adult emergency was observed among 83,4% of parasitized eggs. These data suggest the possibility of using this parasitoid for the pequi caterpillar control, which also causes serious damage on Eucalyptus sp., mainly in Minas Gerais, Brazil.

    KEY-WORDS: Anastatus; parasitoid; egg.

    A ação do parasitóide Anastatus sp. sobre os ovos da D. rosacordis, importante desfolhadora do pequizeiro (Caryocar brasiliense Cambess, foi estudada em ovos coletados no campo e em ovos originados da criação em laboratório. Os ovos foram coletados nos municípios de Hidrolândia, Senador Canedo e Goiânia, Goiás, no início de setembro. Nessas regiões a D. rosacordis apresenta duas gerações, setembro e dezembro. Foi mantida uma criação da D. rosacordis sobre folhas do pequizeiro em condições de laboratório para obtenção de ovos. Os parasitóides emergidos dos ovos coletados no campo foram liberados sobre as massas de ovos obtidos no laboratório. Todas as observações de laboratório foram realizadas sem controle de temperatura, umidade relativa e fotoperíodo. Entre 1.346 ovos obtidos em condições de laboratório, 44,3% foram parasitados, 40,2% foram viáveis e 15,4% não viáveis. Dos 697 coletados no campo, 25,5% estavam parasitados, 58,9% foram viáveis e 15,6% não viáveis. Entre os ovos parasitados foram observadas 83,4% de emergência dos adultos do parasitóide. Estes dados sugerem a possibilidade da utilização desse parasitóide para o controle desta lagarta desfolhadora do pequizeiro, que também causa sérios danos à cultura de Eucalyptus sp., principalmente em Minas Gerais.

    PALAVRAS-CHAVE: Parasitóide; ovos; Caryocar; Anastatus.

  18. Measuring cortical motor hemodynamics during assisted stepping - An fNIRS feasibility study of using a walker.

    Science.gov (United States)

    de Lima-Pardini, Andrea Cristina; Zimeo Morais, Guilherme A; Balardin, Joana Bisol; Coelho, Daniel Boari; Azzi, Nametala Maia; Teixeira, Luis Augusto; Sato, João Ricardo

    2017-07-01

    Walkers are commonly prescribed worldwide to individuals unable to walk independently. Walker usage leads to improved postural control and voluntary movement during step. In the present study, we aimed to provide a concept-proof on the feasibility of an event-related protocol integrating the analyses of biomechanical variables of step initiation and functional near-infrared spectroscopy (fNIRS) to measure activation of the supplementary motor area (SMA) while using a walker. Healthy young participants were tested while stepping with versus without the use of the walker. Behavioral analysis showed that anticipatory postural adjustments (APA) decreased when supporting the body weight on the walker. Delta (without-with) of activation magnitude of the muscle tibialis anterior was positively correlated to the delta of deoxyhemoglobin concentration changes in the SMA. The novelty of this study is the development of a protocol to assess brain function together with biomechanical analysis during the use of a walker. The method sheds light to the potential utility of combining fNIRS and biomechanical assessment during assistive step initiation, which can represent a new opportunity to study populations with mobility deficits. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Dynamic optimization of walker-assisted FES-activated paraplegic walking: simulation and experimental studies.

    Science.gov (United States)

    Nekoukar, Vahab; Erfanian, Abbas

    2013-11-01

    In this paper, we propose a musculoskeletal model of walker-assisted FES-activated paraplegic walking for the generation of muscle stimulation patterns and characterization of the causal relationships between muscle excitations, multi-joint movement, and handle reaction force (HRF). The model consists of the lower extremities, trunk, hands, and a walker. The simulation of walking is performed using particle swarm optimization to minimize the tracking errors from the desired trajectories for the lower extremity joints, to reduce the stimulations of the muscle groups acting around the hip, knee, and ankle joints, and to minimize the HRF. The results of the simulation studies using data recorded from healthy subjects performing walker-assisted walking indicate that the model-generated muscle stimulation patterns are in agreement with the EMG patterns that have been reported in the literature. The experimental results on two paraplegic subjects demonstrate that the proposed methodology can improve walking performance, reduce HRF, and increase walking speed when compared to the conventional FES-activated paraplegic walking. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.

  20. Can intermittent long-range jumps of a random walker compensate for lethargy?

    International Nuclear Information System (INIS)

    Bologna, Mauro; Ahat, Yasin; Grigolini, Paolo; West, Bruce J

    2011-01-01

    We study the dynamics of a lazy random walker who is inactive for extended times and tries to make up for her laziness with very large jumps. She remains in a condition of rest for a time τ derived from a waiting-time distribution ψ(τ)∝1/τ μ W , with μ W μ ξ , with μ ξ > 1. The most convenient choice to make up for the random walker laziness would be to select μ ξ W > 2 would produce Levy flights with scaling δ = 1/(μ ξ - 1) and consequently super-diffusion. According to the Sparre Andersen theorem, the distribution density of the first times to go from x A to x B > x A has the inverse power law form f(t)∝1/(t μ FPT ) with μ FPT = μ SA = 1.5. We find the surprising result that there exists a region of the phase space (μ ξ , μ W ) with μ W FPT > μ SA and the lazy walker compensates for her laziness. There also exists an extended region breaking the Sparre Andersen theorem, where the lazy runner cannot compensate for her laziness. We make conjectures concerning the possible relevance of this mathematical prediction, supported by numerical calculations, for the problem of animal foraging. (fast track communication)

  1. New Analytical Solution of the Equilibrium Ampere's Law Using the Walker's Method: a Didactic Example

    Science.gov (United States)

    Sousa, A. N. Laurindo; Ojeda-González, A.; Prestes, A.; Klausner, V.; Caritá, L. A.

    2018-02-01

    This work aims to demonstrate the analytical solution of the Grad-Shafranov (GS) equation or generalized Ampere's law, which is important in the studies of self-consistent 2.5-D solution for current sheet structures. A detailed mathematical development is presented to obtain the generating function as shown by Walker (RSPSA 91, 410, 1915). Therefore, we study the general solution of the GS equation in terms of the Walker's generating function in details without omitting any step. The Walker's generating function g( ζ) is written in a new way as the tangent of an unspecified function K( ζ). In this trend, the general solution of the GS equation is expressed as exp(- 2Ψ) = 4| K '( ζ)|2/cos2[ K( ζ) - K( ζ ∗)]. In order to investigate whether our proposal would simplify the mathematical effort to find new generating functions, we use Harris's solution as a test, in this case K( ζ) = arctan(exp( i ζ)). In summary, one of the article purposes is to present a review of the Harris's solution. In an attempt to find a simplified solution, we propose a new way to write the GS solution using g( ζ) = tan( K( ζ)). We also present a new analytical solution to the equilibrium Ampere's law using g( ζ) = cosh( b ζ), which includes a generalization of the Harris model and presents isolated magnetic islands.

  2. Effects of aquatic walking exercise using a walker in a chronic stroke patient.

    Science.gov (United States)

    Matsuda, Tadashi; Akezaki, Yoshiteru

    2017-07-01

    [Purpose] The aim of this study was to examine the usefulness of aquatic walking exercise using a walker for chronic stroke patients. We also examined the psychological effects on the study subject and the primary caregiver before and after aquatic walking exercise. [Subject and Methods] The subject was a 60-year-old male with bilateral paralysis after a cerebrovascular accident. The Fugl-Meyer Assessment (FMA) total score was 116 on the right and 115 on the left. The intervention combined aquatic and land walking exercise. A U-shaped walker was used for both water and land exercise. Continuous walking distance was the measure used to evaluate land walking ability. The psychological effects on the study subject and the primary caregiver were examined with the questionnaire. [Results] In aquatic walking, the mean time to walk 5 m showed an increase from the intervention after two months. After the aquatic walking and land walking combination, continuous walking distance also showed a prolonged trend. In the survey given to the main caregivers, improvements were observed. [Conclusion] Aquatic walking practice using a walker improved motivation in a chronic stroke patient, leading to improved walking ability, with a positive psychological influence on the participant and family caregiver.

  3. Upper-Ocean Heat Balance Processes and the Walker Circulation in CMIP5 Model Projections

    Science.gov (United States)

    Robertson, F. R.; Roberts, J. B.; Funk, C.; Lyon, B.; Ricciardulli, L.

    2012-01-01

    Considerable uncertainty remains as to the importance of mechanisms governing decadal and longer variability of the Walker Circulation, its connection to the tropical climate system, and prospects for tropical climate change in the face of anthropogenic forcing. Most contemporary climate models suggest that in response to elevated CO2 and a warmer but more stratified atmosphere, the required upward mass flux in tropical convection will diminish along with the Walker component of the tropical mean circulation as well. Alternatively, there is also evidence to suggest that the shoaling and increased vertical stratification of the thermocline in the eastern Pacific will enable a muted SST increase there-- preserving or even enhancing some of the dynamical forcing for the Walker cell flow. Over the past decade there have been observational indications of an acceleration in near-surface easterlies, a strengthened Pacific zonal SST gradient, and globally-teleconnected dislocations in precipitation. But is this evidence in support of an ocean dynamical thermostat process posited to accompany anthropogenic forcing, or just residual decadal fluctuations associated with variations in warm and cold ENSO events and other stochastic forcing? From a modeling perspective we try to make headway on this question by examining zonal variations in surface energy fluxes and dynamics governing tropical upper ocean heat content evolution in the WCRP CMIP5 model projections. There is some diversity among model simulations; for example, the CCSM4 indicates net ocean warming over the IndoPacific region while the CSIRO model concentrates separate warming responses over the central Pacific and Indian Ocean regions. The models, as with observations, demonstrate strong local coupling between variations in column water vapor, downward surface longwave radiation and SST; but the spatial patterns of changes in the sign of this relationship differ among models and, for models as a whole, with

  4. Effect of Maruca vitrata (Lepidoptera: Crambidae) host plants on life-history parameters of the parasitoid Apanteles taragamae (Hymenoptera: Braconidae)

    NARCIS (Netherlands)

    Dannon, A.E.; Tamo, M.; Agboton, C.; Huis, van A.; Dicke, M.

    2012-01-01

    The effect of four host plant species of the herbivore Maruca vitrata Fabricius (Lepidoptera: Crambidae) on development time, longevity, fecundity and sex ratio of the parasitoid Apanteles taragamae Viereck (Hymenoptera: Braconidae) was investigated under laboratory conditions. The larvae were

  5. Hyperparasitoid wasps (Hymenoptera: Trigonalidae) reared from dry forest and rain forest caterpillars of Area de Conservacion, Guanacaste, Costa Rica

    Science.gov (United States)

    Five species of Trigonalidae, hyperparasites of Ichneumonidae (Hymenoptera) and Tachinidae (Diptera) that parasitize caterpillars (Lepidoptera), have been reared during the ongoing caterpillar inventory of Area de Conservación Guanacaste (ACG), Guanacaste Province, northwestern Costa Rica: Lycogaste...

  6. Role of emerald ash borer (Coleoptera: Buprestidae) larval vibrations in host-quality assessments by Tetrastichus planipennisi (Hymenoptera: Eulophidae)

    Science.gov (United States)

    Michael D. Ulyshen; Richard W. Mankin; Yigen Chen; Jian J. Duan; Therese M. Poland; Leah S. Bauer

    2011-01-01

    The biological control agent Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) is a gregarious larval endoparasitoid of the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), an invasive cambium-feeding species responsible for recent, widespread mortality of ash (Fraxinus spp.) in...

  7. Reproductive and developmental biology of the emerald ash borer parasitoid Spathius galinae (Hymenoptera: Braconidae) as affected by temperature

    Science.gov (United States)

    Emerald ash borer Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) is an invasive pest of serious concern in North America. To complement ongoing biological control efforts, Spathius galinae Belokobylskij and Strazenac (Hymenoptera: Braconidae), a recently-described specialist parasitoid of ...

  8. First record of Aleiodes laphygmae (Hymenoptera: Braconidae) for Argentina and its association with larvae of Spodoptera eridania (Lepidoptera: Noctuidae)

    OpenAIRE

    Valverde, Liliana; Berta, D. Carolina; Gomez, Marcelo Geronimo

    2012-01-01

    Se reporta por primera vez para Argentina Aleiodes laphygmae (Viereck) (Hymenoptera: Braconidae) y como parasitoide de larvas de Spodoptera eridania (Stoll) (Lepidoptera: Noctuidae), en plantaciones de soja en la provincia de Tucumán (Argentina). Se provee información biológica como hábitos, hospedadores y distribución.Aleiodes laphygmae (Viereck) (Hymenoptera: Braconidae), is reported for the first time for Argentina. It is also reported parasitizing larvae of Spodoptera eridania (Stoll) (Le...

  9. Bumble bee (Hymenoptera: Apidae) community structure on two sagebrush steppe sites in southern Idaho

    Science.gov (United States)

    Stephen P. Cook; Sara M. Birch; Frank W. Merickel; Carrie Caselton Lowe; Deborah Page-Dumroese

    2011-01-01

    Although sagebrush, Artemisia spp., does not require an insect pollinator, there are several native species of bumble bees, Bombus spp. (Hymenoptera: Apidae), that are present in sagebrush steppe ecosystems where they act as pollinators for various forbs and shrubs. These native pollinators contribute to plant productivity and reproduction. We captured 12 species of...

  10. The species of the genus Hypodynerus de Saussure (Hymenoptera, Vespidae, Eumeninae occurring in Brazil

    Directory of Open Access Journals (Sweden)

    Bolívar Garcete-Barrett

    2013-04-01

    Full Text Available An identification table and descriptions are given to recognize the two species of Hypodynerus (Hymenoptera: Vespidae: Eumeninae recorded from Brazil: H. arechavaletae (Brèthes and H. duckei (Bertoni comb. n. The lectotype is designated and the male is described for Hypodynerus duckei, its presence being recorded from Brazil for the first time.

  11. The species of the genus Hypodynerus de Saussure (Hymenoptera, Vespidae, Eumeninae) occurring in Brazil.

    Science.gov (United States)

    Garcete-Barrett, Bolívar R; Hermes, Marcel Gustavo

    2013-01-01

    An identification table and descriptions are given to recognize the two species of Hypodynerus (Hymenoptera: Vespidae: Eumeninae) recorded from Brazil: Hypodynerus arechavaletae (Brèthes) and Hypodynerus duckei (Bertoni) comb. n. The lectotype is designated and the male is described for Hypodynerus duckei, its presence being recorded from Brazil for the first time.

  12. [Prevalence of hymenoptera sting allergy in veterinary medicine students from Monterey, Nuevo Leon, Mexico].

    Science.gov (United States)

    Arias Cruz, Alfredo; Monsiváis Toscano, Gina; Gallardo Martínez, Gabriela; González Díaz, Sandra Nora; Galindo Rodríguez, Gabriela

    2007-01-01

    The reported prevalence of allergic systemic reactions to hymenoptera venom occur in up to 3.3% and large local reactions occur in 17% in the general population. To investigate the prevalence of hymenoptera sting allergy in a group of veterinary medicine students from Monterrey, Nuevo Leon, Mexico. A transverse and observational study was done with 64 students of veterinary medicine. We conducted a questionnaire about the students' history of insect allergy and atopy. Skin test with allergenic extracts of bee and ant were practiced to all subjects. We performed aeroallergen skin prick test to the subjets with suspected atopy. Students age ranged from 17 to 25 years (mean 20.2) and 37 were males. Twenty students (31.3%) had clinical history of atopy and positive skin tests to aeroallergens. On the other hand, 5 students (7.8%), including 2 atopic, had suffered large local reactions, but none of them had suffered systemic reactions. Bee and ant skin tests were positive in 15.6% and 31.3% of the students respectively. There was no difference in the prevalence of hymenoptera allergy between atopic and non atopic subjects (p < 0.05). Further, the frequency of atopy in subjects with positive skin tests for bee and ant was 50%. The prevalence of large local reactions and hymenoptera sensitization found in this group was similar to that found in other epidemiologic studies.

  13. First report of Eurytoma plotnikovi Nik. (Hymenoptera, Eurytomidae, a seed parasite of pistachio, in Sicily (Italy

    Directory of Open Access Journals (Sweden)

    Santi Longo

    2011-09-01

    Full Text Available The pistachio seed wasp, Eurytoma plotnikovi Nik.(Hymenoptera, E urytomidae, is a new pest recently arrived in pistachio orchards in central-western Sicily (Italy. Information on the damaging effects of this seed wasp in the affected areas is provided.

  14. Invasive ant Tapinoma melanocephalum (Hymenoptera: Formicidae): A rare quest or increasingly common indoor pest in Europe?

    Czech Academy of Sciences Publication Activity Database

    Klimeš, Petr; Okrouhlík, Jan

    2015-01-01

    Roč. 112, č. 4 (2015), s. 705-712 ISSN 1210-5759 R&D Projects: GA ČR GB14-36098G Institutional support: RVO:60077344 Keywords : Hymenoptera * Formicidae * Tapinoma Subject RIV: EH - Ecology, Behaviour Impact factor: 0.975, year: 2014 http://www.eje.cz/pdfs/eje/2015/04/16.pdf

  15. The species of the Neotropical genus Fractipons Townes, 1970 (Hymenoptera, Ichneumonidae, Cryptinae).

    Science.gov (United States)

    Bordera, Santiago; González-Moreno, Alejandra

    2011-01-19

    In this paper, two new species of the Neotropical genus Fractipons Townes, 1970 (Hymenoptera, Ichneumonidae) are described. A new diagnosis for the genus, a re-description of Fractipons cincticornis Townes, 1970 and a key to known species are provided. New distribution records for the genus now include Argentina, Costa Rica, Panama and Peru.

  16. DNA characterization and karyotypic evolution in the bee genus Melipona (Hymenoptera, Meliponini)

    OpenAIRE

    Rocha, MP; Pompolo, SD; Dergam, JA; Fernandes, A; Campos, LAD

    2002-01-01

    We analyzed patterns of heterochromatic bands in the Neotropical stingless bee genus Melipona (Hymenoptera, Meliponini). Group I species (Melipona bicolor bicolor, Melipona quadrifasciata, Melipona asilvae, Melipona marginata, Melipona subnitida) were characterized by low heterochromatic content. Group 11 species (Melipona capixaba, Melipona compressipes, Melipona crinita, Melipona seminigra fuscopilosa e Melipona scutellaris) had high heterochromatic content. All species had 2n = 18 and n = ...

  17. The Hymenopterous Poison Apparatus. X. Morphological and Behavioral Changes in Atta texana (Hymenoptera: Formicidae)

    Science.gov (United States)

    Henry R. Hermann; John C. Moser; Allen N. Hunt

    1970-01-01

    Atta texana (Buckley) and other members of this genus no longer utilize the 8th and 9th gonapophyses as part of their defensive system. Although the sclerites that comprise the stinging apparatus in most aculeate Hymenoptera are present in the species, they seem to function only in the deposition of trail pheromones. A mechanical and chemical defense...

  18. Epidemiology, Diagnosis, and Treatment of Hymenoptera Venom Allergy in Mastocytosis Patients

    NARCIS (Netherlands)

    Niedoszytko, Marek; Bonadonna, Patrizia; Oude Elberink, Joanne N. G.; Golden, David B. K.

    Hymenoptera venom allergy is a typical IgE-mediated reaction caused by sensitization to 1 or more allergens of the venom, and accounts for 1.5% to 34% of all cases of anaphylaxis. Patients suffering from mastocytosis are more susceptible to the anaphylactic reactions to an insect sting. This article

  19. Application of recombinant antigen 5 allergens from seven allergy-relevant Hymenoptera species in diagnostics

    DEFF Research Database (Denmark)

    Schiener, Maximilian; Eberlein, Bernadette; Moreno Aguilar, Carmen

    2017-01-01

    BACKGROUND: Hymenoptera stings can cause severe anaphylaxis in untreated venom-allergic patients. A correct diagnosis regarding the relevant species for immunotherapy is often hampered by clinically irrelevant cross-reactivity. In vespid venom allergy, cross-reactivity between venoms of different...

  20. The spatial distribution of Hymenoptera parasitoids in a forest reserve in Central Amazonia, Manaus, AM, Brazil

    Directory of Open Access Journals (Sweden)

    RB. Querino

    Full Text Available Parasitoids are of great importance to forest ecosystems due to their ecological role in the regulation of the population of other insects. The species richness and abundance of parasitoids in the forest canopy and understory, both on the borders and in the interior of a tropical forest reserve in Central Amazonia were investigated. For a 12-month period, specimen collections were made every 15 days from suspended traps placed in the forest canopy and in the understory strata, both on the border and in the interior of forest areas. A total of 12,835 Hymenoptera parasitoids from 23 families were acquired. Braconidae, Diapriidae, Mymaridae, Eulophidae, and Scelionidae were the most represented in the area and strata samples. The results indicate that there were no significant differences in the species richness or abundance of Hymenoptera between the forest borders and the inner forest. The data does show that the presence of Hymenoptera is significantly greater in the understory in both the border and interior areas than in the canopy (vertical stratification. Aphelinidae and Ceraphronidae were significantly associated with the inner forest, while the other seven families with the border of the reserve. The abundance of Hymenoptera parasitoids presented seasonal variations during the year related to the rainy and dry seasons.

  1. Revision of the subfamily Euphorinae (excluding the tribe Meteorini Cresson) (Hymenoptera: Braconidae) from China

    NARCIS (Netherlands)

    Chen, X.; Achterberg, van C.

    1997-01-01

    The subfamily Euphorinae (excluding the tribe Meteorini Cresson) (Hymenoptera: Braconidae) from China is revised. In total 150 species, belonging to 24 genera, are treated and keyed. One genus (Heia gen. nov.; type species: Heia robustipes spec. nov.) and 69 species are described as new to science.

  2. Stiff upper lip: Labrum deformity and functionality in bees (Hymenoptera: Apoidea)

    Science.gov (United States)

    In hyper-diverse groups such as Hymenoptera, a variety of structures with different, complementary functions are used for feeding. Although the function of the parts such as the mandibles is obvious, the use of others, like the labrum, is more difficult to discern. Here, we discuss the labrum’s func...

  3. De kortsnuitbloedbij Sphecodes majalis nieuw voor de Nederlandse fauna (Hymenoptera: Apidae)

    NARCIS (Netherlands)

    Raemakers, I.

    2004-01-01

    Sphecodes majalis, a new bee species for the Netherlands (Hymenoptera: Apidae) A population of Sphecodes majalis was found on a limestone grassland near Maastricht (Limburg). On several occasions more than 10 female and several male specimen were observed. Sphecodes majalis is a parasite of

  4. De roodrandzandbij Andrena rosae in de Zuid-Hollandse Biesbosch (Hymenoptera: Apoidea: Andrenidae).

    NARCIS (Netherlands)

    Meer, van der F.; Reemer, M.; Peeters, T.M.J.

    2006-01-01

    Andrena rosae in the Zuid-Hollandse Biesbosch (Hymenoptera: Apoidea: Andrenidae) Andrena rosae is a fairly large, black and red mining bee. It has declined dramatically in the 20th century in northwestern Europe. In the Netherlands the species only survived in and around the Biesbosch, at the

  5. Revision of charipine aphid hyperparasitoids (Hymenoptera, Cynipoidea: Figitidae) from central Europe

    Czech Academy of Sciences Publication Activity Database

    Ferrer-Suay, M.; Starý, Petr; Selfa, J.; Pujade-Villar, J.

    2017-01-01

    Roč. 28, č. 3 (2017), s. 113-147 ISSN 0785-8760 Institutional support: RVO:60077344 Keywords : Hymenoptera * central Europe * aphid Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 0.300, year: 2016 http://www.entomologicafennica.org/Volume28/EF_28_3/1Ferrer-Suay.pdf

  6. Differences in the Limits of Stability Between Older Rolling Walker Users and Older Single-Tip-Cane Users - A Preliminary Study.

    Science.gov (United States)

    Liu, Hao Howe; Quiben, Myles; Holmes, Clayton; Connors, Michael; Salem, Yasser

    To identify the differences in the limits of stability (LOS) between older rolling walker and single-tip-cane users. This was a matched paired t-test design with repeated measure. Eighteen older subjects were matched based on age, gender, and functional level. The subjects were assessed using the multidirectional reach test initially and 5-month later in four directions: forward, backward, leftward, and rightward. Initially, there were no differences between cane users and rolling walker users in the LOS in all directions. However, 5-month later, the cane users who held their canes in their right hand had significantly better stability in forward and rightward reach than the walker users (p walker users demonstrated significantly decreased functional reach in forward reach (p walker users in the forward direction and in the direction toward the side holding the cane. This study may provide guide for clinicians including nurses for selecting appropriate rehabilitative interventions for older adults using walkers and canes.

  7. A review of the New World Atteva Walker moths (Yponomeutidae, Attevinae Resenha das mariposas do gênero Atteva Walker do Novo Mundo (Yponomeutidae, Attevinae

    Directory of Open Access Journals (Sweden)

    Vitor O. Becker

    2009-01-01

    Full Text Available The New World species of Atteva Walker are reviewed and illustrated in colour. One name: A. pustulella (Fabricius, nom. rev. and three species: A. aurea (Fitch, sp. rev., A. floridana (Neumoegen, sp. rev. and A. gemmata (Grote, sp. rev. are reinstated; five names are synonymised under A. aurea: Poeciloptera compta Clemens, syn. n., A. edithella Busck, syn. n., A. exquisita Busck, syn. n., A. ergatica Walsingham, syn. n. and A. microsticta Walsingham, syn. n.; four new species are described: A. rawlinsi sp. n., from the Dominican Republic, A. sidereoides sp. n., from Jamaica, A. entermedia sp. n., from Antigua, and A. zebrina sp. n., from Brazil; lectotypes for A. floridana and A. glaucopidella (Guenée (=fulviguttata are also designated.As species de Atteva Walker são revistas e ilustradas em cores. Um nome: A. pustulella (Fabricius, nom. rev. e três espécies: A. aurea (Fitch, sp. rev., A. floridana (Neumoegen, sp. rev. and A. gemmata (Grote, sp. rev. são restabelecidos; cinco nomes são considerados sinônimos recentes de A.aurea: Poeciloptera compta Clemens, syn. n., A. edithella Busck, syn. n., A. exquisita Busck, syn. n., A. ergatica Walsingham, syn. n. e A. microsticta Walsingham, syn. n.; quatro espécies novas são descritas: A. rawlinsi sp. n., da República Dominica, A. sidereoides sp. n., da Jamaica, A. entermedia sp. n., de Antigua, e A. zebrina sp. n., do Brazil; são designados lectótipos para A. floridana e A. glaucopidella (Guenée (=fulviguttata.

  8. Sting microsculpture in the digger wasp Bembix rostrata (Hymenoptera, Crabronidae

    Directory of Open Access Journals (Sweden)

    Natalia Matushkina

    2011-03-01

    Full Text Available The sting microsculpture of the digger wasp Bembix rostrata (Fabricius, 1781 (Hymenoptera, Crabronidae is studied with the scanning electron microscope (SEM for the first time. As in many other hymenopterans, the second valvifer of B. rostrata possesses two fields of styloconic sensilla (hair plates of proprioceptive function. The presence of two paired fields of campaniform sensilla on the second valvula and second valvifer is first shown in an apoid wasp. The first and the second valvulae bear scattered sensilla-like structures on the external surface, more numerous apically. The first valvula has two subapical barbs externally and a pair of valvilli on its inner surface, whereas the outer surface of the second valvula is smooth. The third valvula is sclerotized externally, consisting of proximal and distal parts, and bearing four sensilla morphotypes of mechanoreceptive and probably chemoreceptive functions. The inner surface of the valvulae and the membranous cuticle that is touching the sting have microstructures of different shapes directed distally. Functional aspects of characters studied are discussed.

  9. Function and evolution of microRNAs in eusocial Hymenoptera

    Directory of Open Access Journals (Sweden)

    Eirik eSovik

    2015-05-01

    Full Text Available The emergence of eusociality (true sociality in several insect lineages represents one of the most successful evolutionary adaptations in the animal kingdom in terms of species richness and global biomass. In contrast to solitary insects, eusocial insects evolved a set of unique behavioral and physiological traits such as reproductive division of labor and cooperative brood care, which likely played a major role in their ecological success. The molecular mechanisms that support the social regulation of behavior in eusocial insects, and their evolution, are mostly unknown. The recent whole-genome sequencing of several eusocial insect species set the stage for deciphering the molecular and genetic bases of eusociality, and the possible evolutionary modifications that led to it. Studies of mRNA expression patterns in the brains of diverse eusocial insect species have indicated that specific social behavioral states of individual workers and queens are often associated with particular tissue-specific transcriptional profiles. Here we discuss recent findings that highlight the role of non-coding microRNAs (miRNAs in modulating traits associated with reproductive and behavioral divisions of labor in eusocial insects. We provide bioinformatic and phylogenetic data, which suggest that some Hymenoptera-specific miRNA may have contributed to the evolution of traits important for the evolution of eusociality in this group.

  10. Foraging strategies of the ant Ectatomma vizottoi (Hymenoptera, Formicidae

    Directory of Open Access Journals (Sweden)

    Luan D. Lima

    2013-12-01

    Full Text Available Foraging strategies of the ant Ectatomma vizottoi (Hymenoptera, Formicidae. Foraging activity may be limited by temperature, humidity, radiation, wind, and other abiotic factors, all of which can affect energy costs during foraging. Ectatomma vizottoi's biology has only recently been studied, and no detailed information is available on its foraging patterns or diet in the field. For this reason, and because foraging activity is an important part of the ecological success of social insects, the present study aimed to investigate E. vizottoi's foraging strategies and dietary habits. First, we determined how abiotic factors constrained E. vizottoi's foraging patterns in the field by monitoring the foraging activity of 16 colonies on eight different days across two seasons. Second, we characterized E. vizottoi's diet by monitoring another set of 26 colonies during peak foraging activity. Our results show that E. vizottoi has foraging strategies that are similar to those of congeneric species. In spite of having a low efficiency index, colonies adopted strategies that allowed them to successfully obtain food resources while avoiding adverse conditions. These strategies included preying on other ant species, a foraging tactic that could arise if a wide variety of food items are not available in the environment or if E. vizottoi simply prefers, regardless of resource availability, to prey on other invertebrates and especially on other ant species.

  11. Preservation of Domesticated Honey Bee (Hymenoptera: Apidae) Drone Semen.

    Science.gov (United States)

    Paillard, M; Rousseau, A; Giovenazzo, P; Bailey, J L

    2017-08-01

    Preservation of honey bee (Apis mellifera L., Hymenoptera: Apidae) sperm, coupled with instrumental insemination, is an effective strategy to protect the species and their genetic diversity. Our overall objective is to develop a method of drone semen preservation; therefore, two experiments were conducted. Hypothesis 1 was that cryopreservation (-196 °C) of drone semen is more effective for long-term storage than at 16 °C. Our results show that after 1 yr of storage, frozen sperm viability was higher than at 16 °C, showing that cryopreservation is necessary to conserve semen. However, the cryoprotectant used for drone sperm freezing, dimethyl sulfoxide (DMSO), can harm the queen and reduce fertility after instrumental insemination. Hypothesis 2 was that centrifugation of cryopreserved semen to reduce DMSO prior to insemination optimize sperm quality. Our results indicate that centrifuging cryopreserved sperm to remove cryoprotectant does not affect queen survival, spermathecal sperm count, or sperm viability. Although these data do not indicate that centrifugation of frozen-thawed sperm improves queen health and fertility after instrumental insemination, we demonstrate that cryopreservation is achievable, and it is better for long-term sperm storage than above-freezing temperatures for duration of close to a year. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Wolbachia in two populations of Melittobia digitata Dahms (Hymenoptera: Eulophidae)

    International Nuclear Information System (INIS)

    Copeland, Claudia S.; Sivinski, John

    2008-01-01

    We investigated two populations of Melittobia digitata Dahms, a gregarious parasitoid (primarily upon a wide range of solitary bees, wasps, and flies), in search of Wolbachia infection. The first population, from Xalapa, Mexico, was originally collected from and reared on Mexican fruit fly pupae, Anastrepha ludens Loew (Diptera: Tephritidae); the other, from Athens, Georgia, was collected from and reared on prepupae of mud dauber wasps, Trypoxylon politum Say (Hymenoptera: Crabronidae). PCR studies of the ITS2 region corroborated that both parasitoid populations were the same species; this potentially provides a useful molecular taxonomic profile since females of Melittobia species are superficially similar. Amplification of the Wolbachia surface protein gene (wsp) confirmed the presence of this endosymbiont in both populations. Sequencing revealed that the Wolbachia harbored in both populations exhibited a wsp belonging to a unique subgroup (denoted here as Dig) within the B-supergroup of known wsp genes. This new subgroup of wsp may either belong to a different strain of Wolbachia from those previously found to infect Melittobia or may be the result of a recombination event. In either case, known hosts of Wolbachia with a wsp of this subgroup are only distantly related taxonomically. Reasons are advanced as to why Melittobia - an easily reared and managed parasitoid - holds promise as an instructive model organism of Wolbachia infection amenable to the investigation of Wolbachia strains among its diverse hosts. (author)

  13. Wolbachia in two populations of Melittobia digitata Dahms (Hymenoptera: Eulophidae)

    Energy Technology Data Exchange (ETDEWEB)

    Copeland, Claudia S.; Sivinski, John [United States Dept. of Agriculture, Gainesville, FL (United States). Center for Medical, Agriculture and Veterinary Entomology]. E-mails: cclaudia@bioinf.uni-leipzig.de; john.sivinski@ars.usda.gov; Matthews, Robert W. [University of Georgia, Athens, GA (United States). Dept. of Entomology]. E-mail: rmatthew@uga.edu; Gonzalez, Jorge M. [Texas A and M Univ., College Station, TX (United States). Dept. of Entomology]. E-mail: jmgonzalez@neo.tamu.edu; Aluja, Martin [Instituto de Ecologia A.C., Veracruz (Mexico)]. E-mail: martin.aluja@inecol.edu.mx

    2008-11-15

    We investigated two populations of Melittobia digitata Dahms, a gregarious parasitoid (primarily upon a wide range of solitary bees, wasps, and flies), in search of Wolbachia infection. The first population, from Xalapa, Mexico, was originally collected from and reared on Mexican fruit fly pupae, Anastrepha ludens Loew (Diptera: Tephritidae); the other, from Athens, Georgia, was collected from and reared on prepupae of mud dauber wasps, Trypoxylon politum Say (Hymenoptera: Crabronidae). PCR studies of the ITS2 region corroborated that both parasitoid populations were the same species; this potentially provides a useful molecular taxonomic profile since females of Melittobia species are superficially similar. Amplification of the Wolbachia surface protein gene (wsp) confirmed the presence of this endosymbiont in both populations. Sequencing revealed that the Wolbachia harbored in both populations exhibited a wsp belonging to a unique subgroup (denoted here as Dig) within the B-supergroup of known wsp genes. This new subgroup of wsp may either belong to a different strain of Wolbachia from those previously found to infect Melittobia or may be the result of a recombination event. In either case, known hosts of Wolbachia with a wsp of this subgroup are only distantly related taxonomically. Reasons are advanced as to why Melittobia - an easily reared and managed parasitoid - holds promise as an instructive model organism of Wolbachia infection amenable to the investigation of Wolbachia strains among its diverse hosts. (author)

  14. Novel and deviant Walker A ATP-binding motifs in bacteriophage large terminase-DNA packaging proteins

    International Nuclear Information System (INIS)

    Mitchell, Michael S.; Rao, Venigalla B.

    2004-01-01

    Bacteriophage terminases constitute a very interesting class of viral-coded multifunctional ATPase 'motors' that apparently drive directional translocation of DNA into an empty viral capsid. A common Walker A motif and other conserved signatures of a critical ATPase catalytic center are identified in the N-terminal half of numerous large terminase proteins. However, several terminases, including the well-characterized λ and SPP1 terminases, seem to lack the classic Walker A in the N-terminus. Using sequence alignment approaches, we discovered the presence of deviant Walker A motifs in these and many other phage terminases. One deviation, the presence of a lysine at the beginning of P-loop, may represent a 3D equivalent of the universally conserved lysine in the Walker A GKT/S signature. This and other novel putative Walker A motifs that first came to light through this study help define the ATPase centers of phage and viral terminases as well as elicit important insights into the molecular functioning of this fundamental motif in biological systems

  15. The influence of septal lesions on sodium and water retention induced by Walker 256 tumor

    Directory of Open Access Journals (Sweden)

    F. Guimarães

    1999-03-01

    Full Text Available In the course of studies on the effects of septal area lesions on neuroimmunomodulation and Walker 256 tumor development, it was observed that tumor-induced sodium and water retention was less marked in lesioned than in non-lesioned rats. In the present study possible mechanisms involved in this phenomenon were investigated. The experiments were performed in septal-lesioned (LW; N = 15 and sham-operated (SW; N = 7 8-week-old male Wistar rats, which received multifocal simultaneous subcutaneous (sc inoculations of Walker 256 tumor cells about 30 days after the stereotaxic surgery. Control groups (no tumor, sham-operated food-restricted (SFR, N = 7 and lesioned food-restricted (LFR, N = 10 were subjected to a feeding pattern similar to that observed in tumor-bearing animals. Multifocal inoculation of Walker 256 tumor rapidly induces anorexia, which is paradoxically accompanied by an increase in body weight, as a result of renal Na+ and fluid retention. These effects of the tumor were also seen in LW rats, although the rise in fractional sodium balance during the early clinical period was significantly smaller than in SW rats (day 4: SW = 47.6 ± 6.4% and LW = 13.8 ± 5.2%; day 5: SW = 57.5 ± 3.5% and LW = 25.7 ± 4.8%; day 6: SW = 54.4 ± 3.8% and LW = 32.1 ± 4.4%; P<0.05, suggesting a temporary reduction in tumor-induced sodium retention. In contrast, urine output was significantly reduced in SW rats and increased in LW rats (LW up to -0.85 and SW up to 4.5 ml/100 g body weight, with no change in osmolar excretion. These temporary changes in the tumor's effects on LW rats may reflect a "reversal" of the secondary central antidiuretic response induced by the tumor (from antidiuretic to diuretic.

  16. Do Canes or Walkers Make Any Difference? NonUse and Fall Injuries.

    Science.gov (United States)

    Luz, Clare; Bush, Tamara; Shen, Xiaoxi

    2017-04-01

    Examine patterns of cane and walker use as related to falls and fall injuries. Among people who fall at home, most do not have an assistive device with them when they fall. Nonusers who fall sustain more severe injuries. This was a cross-sectional study using a self-administered written survey completed by 262 people aged 60 and older who were community dwelling, cognitively intact, and current cane/walker users with a history of falls. They were recruited through clinical practice sites, churches, and senior housing in central Michigan. Outcomes of interest included patterns of device use, reasons for nonuse, device use at time of fall, and fall-related injuries. Seventy-five percent of respondents who fell were not using their device at the time of fall despite stating that canes help prevent falls. Reasons for nonuse included believing it was not needed, forgetfulness, the device made them feel old, and inaccessibility. Perceived risk was not high enough to engage in self-protective behavior. However, nonuse led to a significantly higher proportion of falls resulting in surgery than among device users. Among respondents requiring surgery, 100% were nonusers. Most respondents never received a home safety evaluation (68%) and only 50% received training on proper device use. Providers must place increased emphasis on the importance of cane/walker use for injury prevention through patient education to promote personal relevance, proper fitting, and training. New strategies are needed to improve device acceptability and accessibility. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Computation of partially invariant solutions for the Einstein Walker manifolds' identifying equations

    Science.gov (United States)

    Nadjafikhah, Mehdi; Jafari, Mehdi

    2013-12-01

    In this paper, partially invariant solutions (PISs) method is applied in order to obtain new four-dimensional Einstein Walker manifolds. This method is based on subgroup classification for the symmetry group of partial differential equations (PDEs) and can be regarded as the generalization of the similarity reduction method. For this purpose, those cases of PISs which have the defect structure δ=1 and are resulted from two-dimensional subalgebras are considered in the present paper. Also it is shown that the obtained PISs are distinct from the invariant solutions that obtained by similarity reduction method.

  18. Combined therapy of the Walker-256 carcinosarcoma with X-rays and ICRF-159

    International Nuclear Information System (INIS)

    Schaphaus, A.

    1974-01-01

    The radiosensitivity of the Walker-256 carcinosarcoma of the rat under the influence of the tumour-inhibiting bisdioxopiperazine ICRF-159 was studied in collectives of 11-16 animals with tumours. In the combined radio- and chemotherapy, the animals received a daily i.p. injection of 30 mg/kg K.G. of the bisdioxopiperazine ICRF-159 in 1.0 ml NaCl solution containing carboxyl methyl cellulose. The tumour inhibition was determined by multidimensional measurements of the increase in tumour size with the aid of a slide gange. The combined therapy had a better inhibiting effect on tumour growth than radiotherapy alone. (orig./AK) [de

  19. On the spectrum of particles created in a Robertson-Walker universe

    International Nuclear Information System (INIS)

    Azuma, T.

    1983-01-01

    Created particle spectra are calculated in Robertson-Walker universes and discussed with a special emphasis on their dependence upon the initial and final times at which a WKB-like positive frequency conditions should be imposed. It is shown that the obtained spectra are very sensitive to these times if the WKB approximation for the field equation is not valid in their neighborhood. It is also shown that the total number density of created particles remains finite if the final time is set to be finite. (author)

  20. Finite-temperature effects in the φ4-model in a Robertson-Walker universe

    International Nuclear Information System (INIS)

    Kundu, P.K.

    1987-01-01

    The computation of the one-loop trace anomaly in a massless, conformally coupled φ 4 -model displaying spontaneous symmetry breaking in a spatially flat Robertson-Walker universe investigated in a previous paper, is extended to the case in which the physical system is in a state of thermal equilibrium. It is found that due to a nonperturbative nature of this effect the anomalous trace exhibits a rather nontrivial temperature dependence and cannot be expressed as a sum of contributions from the vacuum state and an ideal black-body radiation gas

  1. Changes in Central Walker Lane Strain Accommodation near Bridgeport, California; as told by the Stanislaus Group

    Science.gov (United States)

    Carlson, C. W.; Pluhar, C. J.; Glen, J. M.; Farner, M. J.

    2012-12-01

    Accommodating ~20-25% of the dextral-motion between the Pacific and North American plates the Walker Lane is represented as an elongate, NW oriented, region of active tectonics positioned between the northwesterly-translating Sierra Nevada microplate and the east-west extension of the Basin and Range. This region of transtension is being variably accommodated on regional-scale systems of predominantly strike-slip faulting. At the western edge of the central Walker Lane (ca. 38°-39°N latitude) is a region of crustal-scale blocks bounded by wedge-shaped depositional-basins and normal-fault systems, here defined as the west-central Walker Lane (WCWL). Devoid of obvious strike-slip faulting, the presence of tectonic-block vertical-axis rotations in the WCWL represents unrecognized components of dextral-shearing and/or changes of strain-accommodation over time. We use paleomagnetic reference directions for Eureka Valley Tuff (EVT) members of the late Miocene Stanislaus Group as spatial and temporal markers for documentation of tectonic-block vertical-axis rotations near Bridgeport, CA. Study-site rotations revealed discrete rotational domains of mean vertical-axis rotation ranging from ~10°-30° with heterogeneous regional distribution. Additionally, the highest measured magnitudes of vertical-axis rotation (~50°-60° CW) define a 'Region of High Strain' that includes the wedge-shaped Bridgeport Valley (Basin). This study revealed previously-unrecognized tectonic rotation of reference direction sites from prior studies for two (By-Day and Upper) of the three members of the EVT, resulting in under-estimates of regional strain accommodation by these studies. Mean remanent directions and virtual geomagnetic poles utilized in our study yielded a recalculated reference direction for the By-Day member of: Dec.=353.2°; Inc.= 43.7°; α95=10.1, in agreement with new measurements in the stable Sierra Nevada. This recalculated direction confirmed the presence of previously

  2. Energy-momentum tensor and definition of particle states for Robertson-Walker space-time

    International Nuclear Information System (INIS)

    Brown, M.R.; Dutton, C.R.

    1978-01-01

    A new regularization scheme is developed for calculating expectation values of the energy-momentum tensor of a quantized scalar field in Robertson-Walker space-times. Using this regularized stress tensor we consider a definition for the vacuum state of the scalar field on any initial hypersurface. Asymptotic methods are developed to investigate the structure of both the divergent and finite terms of the stress tensor when evaluated in this state. The conformal anomaly is discussed in the context of this model. It does not naturally enter into the analysis and we argue that its inclusion is unnecessary

  3. Lanczos potentials and a definition of gravitational entropy for perturbed Friedman-Lemaitre-Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Mena, Filipe C; Tod, Paul

    2007-01-01

    We give a prescription for constructing a Lanczos potential for a cosmological model which is a purely gravitational perturbation of a Friedman-Lemaitre-Robertson-Walker spacetime. For the radiation equation of state, we find the Lanczos potential explicitly via Fourier transforms. As an application, we follow up a suggestion of Penrose (1979 Singularities and time-asymmetry General Relativity: An Einstein Centenary Survey ed S W Hawking and W Israel (Cambridge: Cambridge University Press)) and propose a definition of gravitational entropy for these cosmologies. With this definition, the gravitational entropy initially is finite if and only if the initial Weyl tensor is finite

  4. Dandy Walker Syndrome with Unusual Associated Findings in a Fetal Autopsy Study

    Directory of Open Access Journals (Sweden)

    Surekha U Arakeri

    2015-01-01

    Full Text Available Dandy Walker Syndrome (DWS is a congenital brain malformation characterized by hypoplasia or absence of cerebellar vermis, cystic dilatation of fourth ventricle and hydrocephalus. It is frequently associated with other congenital anomalies. Associated central nervous system anomalies such as agenesis of corpus callosum and vermis are associated with poor prognosis. Association of DWS with congenital absence of spleen is life threatening condition and has been reported very rarely. Autopsy findings of DWS with association of congenital absence of corpus callosum, vermis and spleen are reported in a stillborn fetus of 28 weeks gestation and review of relevant literature was done

  5. Beyond the Friedmann—Lemaître—Robertson—Walker Big Bang Singularity

    International Nuclear Information System (INIS)

    Stoica, Cristi

    2012-01-01

    Einstein's equation, in its standard form, breaks down at the Big Bang singularity. A new version, equivalent to Einstein's whenever the latter is defined, but applicable in wider situations, is proposed. The new equation remains smooth at the Big Bang singularity of the Friedmann—Lemaître—Robertson—Walker model. It is a tensor equation defined in terms of the Ricci part of the Riemann curvature. It is obtained by taking the Kulkarni—Nomizu product between Einstein's equation and the metric tensor.

  6. Accommodation of missing shear strain in the Central Walker Lane, western North America: Constraints from dense GPS measurements

    Science.gov (United States)

    Bormann, Jayne M.; Hammond, William C.; Kreemer, Corné; Blewitt, Geoffrey

    2016-04-01

    We present 264 new interseismic GPS velocities from the Mobile Array of GPS for Nevada Transtension (MAGNET) and continuous GPS networks that measure Pacific-North American plate boundary deformation in the Central Walker Lane. Relative to a North America-fixed reference frame, northwestward velocities increase smoothly from ∼4 mm/yr in the Basin and Range province to 12.2 mm/yr in the central Sierra Nevada resulting in a Central Walker Lane deformation budget of ∼8 mm/yr. We use an elastic block model to estimate fault slip and block rotation rates and patterns of deformation from the GPS velocities. Right-lateral shear is distributed throughout the Central Walker Lane with strike-slip rates generally Bodie Hills, Carson Domain, and Mina Deflection are between 1-4°/Myr, lower than published paleomagnetic rotation rates, suggesting that block rotation rates have decreased since the Late to Middle Miocene.

  7. Epidemiological study of the prevalence of allergic reactions to Hymenoptera in a rural population in the Mediterranean area.

    Science.gov (United States)

    Fernandez, J; Blanca, M; Soriano, V; Sanchez, J; Juarez, C

    1999-08-01

    Systemic allergic reactions to Hymenoptera venom occur in a percentage that varies from 0.4 to 3.3%. Epidemiological studies indicate that from 15 to 25% of the general population can be sensitized to different Hymenoptera venom as well as the fact that the degree of exposure may be related to the prevalence found in those studies. The objective of this study was to evaluate the prevalence of insect sting allergy and the venom sensitization in a rural population to three Hymenoptera previously found in the area: Polistes dominulus (Pd), Vespula germanica (Vg) and honey bee (Hb). A rural community located in the south-east of Spain, close to the Mediterranean Sea, was selected since the stinging Hymenoptera having been previously identified. A random sample of 310 subjects from the village census was studied. A questionnaire and a serum sample were obtained from every patient. The evaluation was conducted by a family doctor, who focused on the reactions to Hymenoptera sting, age, sex, occupation, atopia, previous Hymenoptera sting, stinging insect, interval to last sting and average stings per year. RAST to Hymenoptera venoms were also determined. The prevalence of systemic reactions was 2.3% (57.6% of them had a positive RAST). Large local reactions were found in 26.4% (only 28.5% of them had a positive RAST). Asymptomatic sensitization (positive RAST) was observed in 16.4% of subjects without reaction. Only a weak correlation between subjects with less than 3 years' interval to last sting exposure and positive RAST results was noted, whether they presented with a clinical reaction or not (P < 0.05). The prevalence of systemic sting reactions in our rural community is higher than other general populations in the same Mediterranean area, and similar to other rural populations studied. The degree of exposure influences not only the prevalence found but also the detection of specific serum IgE.

  8. Nesting biology of Centris (Hemisiella tarsata Smith (Hymenoptera, Apidae, Centridini

    Directory of Open Access Journals (Sweden)

    Cândida M. L. Aguiar

    2004-09-01

    Full Text Available Nests of Centris tarsata Smith, 1874 were obtained from trap-nests in areas of dry semi-deciduous forest (Baixa Grande and caatinga (Ipirá, in the State of Bahia. Nesting occurred in bamboo canes and in tubes of black cardboard with 5.8 cm (= small tube and 10.5 cm (= large tube in length and 0.6 and 0.8 cm in diameter, respectively. In both areas C. tarsata nested during the wet season producing four generations in Baixa Grande and three generations in Ipirá. The immatures of one generation underwent diapause at both sites. The bees constructed their nests with a mixture of sand and oil. In general, the cells were elongated and arranged in linear series with its opening pointing towards the nest entrance. Completed nests had two to three cells in small tubes, one to seven cells in large tubes, and two to 13 cells in bamboo canes. The nest plug resembled an uncompleted cell and was externally covered with oil. The cells were provisioned with pollen, oil, and nectar. Nests were parasitized by Mesocheira bicolor (Fabricius, 1804 (Hymenoptera: Apidae and other not identify bee species.Ninhos de Centris tarsata Smith, 1874 foram obtidos através da utilização de ninhos-armadilha, em áreas de floresta estacional semi-decídua (Baixa Grande e de caatinga (Ipirá, no Estado da Bahia. A nidificação ocorreu em gomos de bambus e em tubos de cartolina preta, estes com comprimentos de 5,8 cm (= tubos pequenos e 10,5 cm (= tubos grandes, e diâmetro de 0,6 e 0,8 cm, respectivamente. Em ambas as áreas C. tarsata nidificou durante a estação úmida, produzindo quatro gerações anuais em Baixa Grande e três em Ipirá. Os imaturos de uma das gerações passaram por diapausa em ambos os locais. As abelhas construíram seus ninhos com uma mistura de areia e óleo. Em geral, as células foram alongadas e arranjadas em série linear, com sua abertura dirigida para a entrada do ninho. Os ninhos completados tinham de duas a três células nos tubos pequenos

  9. Unintentional fall injuries associated with walkers and canes in older adults treated in U.S. emergency departments.

    Science.gov (United States)

    Stevens, Judy A; Thomas, Karen; Teh, Leesia; Greenspan, Arlene I

    2009-08-01

    To characterize nonfatal, unintentional, fall-related injuries associated with walkers and canes in older adults. Surveillance data of injuries treated in hospital emergency departments (EDs), January 1, 2001, to December 31, 2006. The National Electronic Injury Surveillance System All Injury Program, which collects data from a nationally representative stratified probability sample of 66 U.S. hospital EDs. People aged 65 and older treated in EDs for 3,932 nonfatal unintentional fall injuries and whose records indicated that a cane or a walker was involved in the fall. Sex, age, whether the fall involved a cane or walker, primary diagnosis, part of the body injured, disposition, and location and circumstances of the fall. An estimated 47,312 older adult fall injuries associated with walking aids were treated annually in U.S. EDs: 87.3% with walkers, 12.3% with canes, and 0.4% with both. Walkers were associated with seven times as many injuries as canes. Women's injury rates exceeded those for men (rate ratios=2.6 for walkers, 1.4 for canes.) The most prevalent injuries were fractures and contusions or abrasions. Approximately one-third of subjects were hospitalized for their injuries. Injuries and hospital admissions for falls associated with walking aids were frequent in this highly vulnerable population. The results suggest that more research is needed to improve the design of walking aids. More information also is needed about the circumstances preceding falls, both to better understand the contributing fall risk factors and to develop specific and effective fall prevention strategies.

  10. Fertility signals in the bumblebee Bombus terrestris (Hymenoptera: Apidae)

    Science.gov (United States)

    Sramkova, A.; Schulz, C.; Twele, R.; Francke, W.; Ayasse, M.

    2008-06-01

    In eusocial Hymenoptera, queen control over workers is probably inseparable from the mechanism of queen recognition. In primitively eusocial bumblebees ( Bombus), worker reproduction is controlled not only by the presence or absence of a dominant queen but also by other dominant workers. Furthermore, it was shown that the queen dominance is maintained by pheromonal cues. We investigated whether there is a similar odor signal released by egg-laying queens and workers that may have a function as a fertility signal. We collected cuticular surface extracts from nest-searching and breeding Bombus terrestris queens and workers that were characterized by their ovarian stages. In chemical analyses, we identified 61 compounds consisting of aldehydes, alkanes, alkenes, and fatty acid esters. Nest-searching queens and all groups of breeding females differed significantly in their odor bouquets. Furthermore, workers before the competition point (time point of colony development where workers start to develop ovaries and lay eggs) differed largely from queens and all other groups of workers. Breeding queens showed a unique bouquet of chemical compounds and certain queen-specific compounds, and the differences toward workers decrease with an increasing development of the workers’ ovaries, hinting the presence of a reliable fertility signal. Among the worker groups, the smallest differences were found after the competition point. Egg-laying females contained higher total amounts of chemical compounds and of relative proportions of wax-type esters and aldehydes than nest-searching queens and workers before the competition point. Therefore, these compounds may have a function as a fertility signal present in queens and workers.

  11. Simplification of intradermal skin testing in Hymenoptera venom allergic children.

    Science.gov (United States)

    Cichocka-Jarosz, Ewa; Stobiecki, Marcin; Brzyski, Piotr; Rogatko, Iwona; Nittner-Marszalska, Marita; Sztefko, Krystyna; Czarnobilska, Ewa; Lis, Grzegorz; Nowak-Węgrzyn, Anna

    2017-03-01

    The direct comparison between children and adults with Hymenoptera venom anaphylaxis (HVA) has never been extensively reported. Severe HVA with IgE-documented mechanism is the recommendation for venom immunotherapy, regardless of age. To determine the differences in the basic diagnostic profile between children and adults with severe HVA and its practical implications. We reviewed the medical records of 91 children and 121 adults. Bee venom allergy was exposure dependent, regardless of age (P bee venom allergic group, specific IgE levels were significantly higher in children (29.5 kU A /L; interquartile range, 11.30-66.30 kU A /L) compared with adults (5.10 kU A /L; interquartile range, 2.03-8.30 kU A /L) (P venom were higher in bee venom allergic children compared with the wasp venom allergic children (P venom. At concentrations lower than 0.1 μg/mL, 16% of wasp venom allergic children and 39% of bee venom allergic children had positive intradermal test results. The median tryptase level was significantly higher in adults than in children for the entire study group (P = .002), as well as in bee (P = .002) and wasp venom allergic groups (P = .049). The basic diagnostic profile in severe HVA reactors is age dependent. Lower skin test reactivity to culprit venom in children may have practical application in starting the intradermal test procedure with higher venom concentrations. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  12. Genomic and karyotypic variation in Drosophila parasitoids (Hymenoptera, Cynipoidea, Figitidae

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    Vladimir Gokhman

    2011-08-01

    Full Text Available Drosophila melanogaster Meigen, 1830 has served as a model insect for over a century. Sequencing of the 11 additional Drosophila Fallen, 1823 species marks substantial progress in comparative genomics of this genus. By comparison, practically nothing is known about the genome size or genome sequences of parasitic wasps of Drosophila. Here, we present the first comparative analysis of genome size and karyotype structures of Drosophila parasitoids of the Leptopilina Förster, 1869 and Ganaspis Förster, 1869 species. The gametic genome size of Ganaspis xanthopoda (Ashmead, 1896 is larger than those of the three Leptopilina species studied. The genome sizes of all parasitic wasps studied here are also larger than those known for all Drosophila species. Surprisingly, genome sizes of these Drosophila parasitoids exceed the average value known for all previously studied Hymenoptera. The haploid chromosome number of both Leptopilina heterotoma (Thomson, 1862 and L. victoriae Nordlander, 1980 is ten. A chromosomal fusion appears to have produced a distinct karyotype for L. boulardi (Barbotin, Carton et Keiner-Pillault, 1979 (n = 9, whose genome size is smaller than that of wasps of the L. heterotoma clade. Like L. boulardi, the haploid chromosome number for G. xanthopoda is also nine. Our studies reveal a positive, but non linear, correlation between the genome size and total chromosome length in Drosophila parasitoids. These Drosophila parasitoids differ widely in their host range, and utilize different infection strategies to overcome host defense. Their comparative genomics, in relation to their exceptionally well-characterized hosts, will prove to be valuable for understanding the molecular basis of the host-parasite arms race and how such mechanisms shape the genetic structures of insect communities.

  13. Thermoperiodism Synchronizes Emergence in the Alfalfa Leafcutting Bee (Hymenoptera: Megachilidae).

    Science.gov (United States)

    Yocum, George D; Rinehart, Joseph P; Yocum, Ian S; Kemp, William P; Greenlee, Kendra J

    2016-02-01

    Alfalfa seed production in the northwestern United States and western Canada is heavily dependent upon the pollinating services of Megachile rotundata (F.) (Hymenoptera: Megachilidae). M. rotundata females nest in cavities either naturally occurring or in artificial nesting blocks. Because of the physical nature of the nest, M. rotundata brood may have limited to no exposure to photoperiodic cues in order to regulate important circadian functions. Therefore, various thermoperiod regimes were used to characterize the possible role of thermoperiodism in synchronizing M. rotundata adult emergence. Adult emergence was monitored using a microprocessor-controlled event logger. Incubating bees under constant 29°C and darkness resulted in an arhythmic adult emergence pattern. Exposing developing M. rotundata to a thermoperiod synchronized emergence to the beginning of the thermophase and decreased the total number of days required for all adults to emerge. The amplitude of the thermoperiod regulated the timing of peak emergence in relationship to the increase in temperature. A thermoperiod amplitude of only 2°C was sufficient to synchronize peak adult emergence to take place during the rise in temperature. Increasing the amplitude of the thermoperiod to 4 or 8°C caused a positively correlated shift in peak emergence to later in the thermophase. Brood stored under constant 29°C and darkness for different durations (May or June early in the growing season or July or August late in the growing season) or under a fluctuating thermal regime (base temperature of 6°C and daily 1-h pulse of 20°C until September or November) maintained their capacity for entraining emergence timing by thermoperiodism. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

  14. Determining the Walker exponent and developing a modified Smith-Watson-Topper parameter model

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Zhiqiang; Huang, Hong Zhong; Wang, Hai Kun; Gao, Huiying; Zuo, Fang Jun [University of Electronic Science and Technology of China, Chengdu (China)

    2016-03-15

    Mean stress effects significantly influence the fatigue life of components. In general, tensile mean stresses are known to reduce the fatigue life of components, whereas compressive mean stresses are known to increase it. To date, various methods that account for mean stress effects have been studied. In this research, considering the high accuracy of mean stress correction and the difficulty in obtaining the material parameter of the Walker method, a practical method is proposed to describe the material parameter of this method. The test data of various materials are then used to verify the proposed practical method. Furthermore, by applying the Walker material parameter and the Smith-Watson-Topper (SWT) parameter, a modified strain-life model is developed to consider sensitivity to mean stress of materials. In addition, three sets of experimental fatigue data from super alloy GH4133, aluminum alloy 7075-T651, and carbon steel are used to estimate the accuracy of the proposed model. A comparison is also made between the SWT parameter method and the proposed strainlife model. The proposed strain-life model provides more accurate life prediction results than the SWT parameter method.

  15. Grain-size data from four cores from Walker Lake, Nevada

    International Nuclear Information System (INIS)

    Yount, J.C.; Quimby, M.F.

    1990-01-01

    A number of cores, taken from within and near Walker Lake, Nevada are being studied by various investigators in order to evaluate the late-Pleistocene paleoclimate of the west-central Great Basin. In particular, the cores provide records that can be interpreted in terms of past climate and compared to proposed numerical models of the region's climate. All of these studies are being carried out as part of an evaluation of the regional paleoclimatic setting of a proposed high-level nuclear waste storage facility at Yucca Mountain, Nevada. Changes in past climate often manifest themselves in changes in sedimentary processes or in changes in the volume of sediment transported by those processes. One fundamental sediment property that can be related to depositional processes is grain size. Grain size effects other physical properties of sediment such as porosity and permeability which, in turn, affect the movement and chemistry of fluids. The purposes of this report are: (1) to document procedures of sample preparation and analysis, and (2) to summarize grain-size statistics for 659 samples from Walker Lake cores 84-4, 84-5, 84-8 and 85-2. Plots of mean particle diameter, percent sand, and the ratio of silt to clay are illustrated for various depth intervals within each core. Summary plots of mean grain size, sorting, and skewness parameters allow comparison of textural data between each core. 15 refs., 8 figs., 3 tabs

  16. Neimark-Sacker bifurcations and evidence of chaos in a discrete dynamical model of walkers

    International Nuclear Information System (INIS)

    Rahman, Aminur; Blackmore, Denis

    2016-01-01

    Bouncing droplets on a vibrating fluid bath can exhibit wave-particle behavior, such as being propelled by interacting with its own wave field. These droplets seem to walk across the bath, and thus are dubbed walkers. Experiments have shown that walkers can exhibit exotic dynamical behavior indicative of chaos. While the integro-differential models developed for these systems agree well with the experiments, they are difficult to analyze mathematically. In recent years, simpler discrete dynamical models have been derived and studied numerically. The numerical simulations of these models show evidence of exotic dynamics such as period doubling bifurcations, Neimark–Sacker (N–S) bifurcations, and even chaos. For example, in [1], based on simulations Gilet conjectured the existence of a supercritical N-S bifurcation as the damping factor in his one- dimensional path model. We prove Gilet’s conjecture and more; in fact, both supercritical and subcritical (N-S) bifurcations are produced by separately varying the damping factor and wave-particle coupling for all eigenmode shapes. Then we compare our theoretical results with some previous and new numerical simulations, and find complete qualitative agreement. Furthermore, evidence of chaos is shown by numerically studying a global bifurcation.

  17. Dandy–Walker malformation is a rare cause of syringomyelia in adults

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    G. Yu. Evzikov

    2017-01-01

    Full Text Available Neural tube defects are the most common central nervous system malformation. Dandy–Walker malformation (DWM is a rare abnormality of the posterior cranial fossa, which is generally diagnosed in the prenatal period or early infancy.The paper describes a case of the late clinical manifestation of DWM, which has caused syringomyelia. All variants of pathological changes within the Dandy–Walker complex very rarely become a cause of syringomyelia. Only four cases of DWM, in which syringomyelia was found in adults, are known.The authors believe that formation of syringomyelia cysts in these patients is associated with the impaired circulation of normal cerebrospinal fluid between the superior cistern and the subarachnoid spaces of the spinal cord due to the caudal dislocation of the cyst formed in the fourth ventricle.Decompression of the craniovertebral junction, by resecting the caudal portion of the cyst in the foramen magnum, and repair of the free communication between the superior cistern and the cerebrospinal fluid spaces of the spinal cord, which is complemented by duroplasty, are pointed out to be an optimal treatment in these patients.

  18. Anestesia em criança com síndrome de Walker-Warburg

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    Emine Arzu Kose

    2014-04-01

    Full Text Available Justificativa e objetivos: A síndrome de Walker-Warburg é uma distrofia muscular autossômica recessiva congênita rara, manifestada pelo sistema nervoso central com malformações oculares e possível envolvimento de vários sistemas. O diagnóstico é estabelecido pela presença de quatro critérios: distrofia muscular congênita, lisencefalia tipo II, malformação cerebelar e malformação da retina. A maioria das crianças com a síndrome morre nos primeiros três anos de vida por causa de insuficiência respiratória, pneumonia, convulsões, hipertermia e fibrilação ventricular. Relato de caso: É discutida a conduta anestésica em uma criança do sexo masculino, de dois meses, programada para cirurgia eletiva de derivação ventrículo-peritoneal. Conclusões: Uma abordagem anestésica cuidadosa é necessária por causa do envolvimento de vários sistemas. Relatamos a conduta anestésica em uma criança do sexo masculino de dois meses com síndrome de Walker-Warburg, que foi programada para cirurgia eletiva de derivação ventrículo-peritoneal.

  19. A class of almost equilibrium states in Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Kueskue, Muharrem

    2008-01-01

    In quantum field theory in curved spacetimes the construction of the algebra of observables of linear fields is today well understood. However, it remains a non-trivial task to construct physically meaningful states on the algebra. For instance, we are in the unsatisfactory situation that there exist no examples of states suited to describe local thermal equilibrium in a non-stationary spacetime. In this thesis, we construct a class of states for the Klein-Gordon field in Robertson-Walker spacetimes, which seem to provide the first example of thermal states in a spacetime without time translation symmetry. More precisely, in the setting of real, linear, scalar fields in Robertson-Walker spacetimes we define on the set of homogeneous, isotropic, quasi-free states a free energy functional that is based on the averaged energy density measured by an isotropic observer along his worldline. This functional is well defined and lower bounded by a suitable quantum energy inequality. Subsequently, we minimize this functional and obtain states that we interpret as 'almost equilibrium states'. It turns out that the states of low energy are the ground states of the almost equilibrium states. Finally, we prove that the almost equilibrium states satisfy the Hadamard condition, which qualifies them as physically meaningful states. (orig.)

  20. A class of almost equilibrium states in Robertson-Walker spacetimes

    Energy Technology Data Exchange (ETDEWEB)

    Kueskue, Muharrem

    2008-11-06

    In quantum field theory in curved spacetimes the construction of the algebra of observables of linear fields is today well understood. However, it remains a non-trivial task to construct physically meaningful states on the algebra. For instance, we are in the unsatisfactory situation that there exist no examples of states suited to describe local thermal equilibrium in a non-stationary spacetime. In this thesis, we construct a class of states for the Klein-Gordon field in Robertson-Walker spacetimes, which seem to provide the first example of thermal states in a spacetime without time translation symmetry. More precisely, in the setting of real, linear, scalar fields in Robertson-Walker spacetimes we define on the set of homogeneous, isotropic, quasi-free states a free energy functional that is based on the averaged energy density measured by an isotropic observer along his worldline. This functional is well defined and lower bounded by a suitable quantum energy inequality. Subsequently, we minimize this functional and obtain states that we interpret as 'almost equilibrium states'. It turns out that the states of low energy are the ground states of the almost equilibrium states. Finally, we prove that the almost equilibrium states satisfy the Hadamard condition, which qualifies them as physically meaningful states. (orig.)

  1. Metabolic changes during development of Walker-256 carcinosarcoma resistance to doxorubicin.

    Science.gov (United States)

    Todor, I N; Lukyanova, N Yu; Shvets, Yu V; Lozovska, Yu V; Chekhun, V F

    2015-03-01

    To study indices of energy metabolism, content of K(+) and Mg(++) both in peripheral blood and in Walker-256 carcinosarcoma during development of resistance to doxorubicin. Resistance of Walker-256 carcinosarcoma to doxorubicin has been developed through 12 subsequent transplantations of tumor after the chemotherapy. Parental strain was inhibited by drug by 65%, while transitional resistant substrains - by 30% and 2%, respectively. Determination of biochemical indices in blood serum and homogenates of tumor tissue, level of potassium, magnesium, lactate, glucose, activities of lactate dehydrogenase and glucose-6-phosphate dehydrogenase was performed with the help of biochemical and immune-enzyme analyzer GBG ChemWell 2990 (USA) using standard kits. Polarography was used to determine indices of mitochondrial oxidative phosphorylation. Study of mitochondrial membrane potential was carried out on flow cytometer Beckman Coulter Epics XL using dye JC-1. It has been determined that development of drug resistance causes the decrease of K(+), Mg(++), glucose content in blood serum and increase of these indices in tumor tissue. At the same time, gradual tumor's loss of sensitivity is characterized by decrease of glycolysis activity in it and activation of mitochondrial oxidative phosphorylation and pentose phosphate pathway of glucose degradation, which causes more intensive formation of NADPH. Development of drug resistance of tumor causes certain metabolic changes in organism and tumor. Further study of such changes will make possible to determine tumor and extratumor markers of resistance.

  2. POMT1-associated walker-warburg syndrome: a disorder of dendritic development of neocortical neurons.

    Science.gov (United States)

    Judas, M; Sedmak, G; Rados, M; Sarnavka, V; Fumić, K; Willer, T; Gross, C; Hehr, U; Strahl, S; Cuk, M; Barić, I

    2009-02-01

    We have analyzed the morphology and dendritic development of neocortical neurons in a 2.5-month-old infant with Walker-Warburg syndrome homozygotic for a novel POMT1 gene mutation, by Golgi methods. We found that pyramidal neurons frequently displayed abnormal (oblique, horizontal, or inverted) orientation. A novel finding of this study is that members of the same population of pyramidal neurons display different stages of development of their dendritic arborizations: some neurons had poorly developed dendrites and thus resembled pyramidal neurons of the late fetal cortex; for some neurons, the level of differentiation corresponded to that in the newborn cortex; finally, some neurons had quite elaborate dendritic trees as expected for the cortex of 2.5-month-old infant. In addition, apical dendrites of many pyramidal neurons were conspiciously bent to one side, irrespective to the general orientation of the pyramidal neuron. These findings suggest that Walker-Warburg lissencephaly is characterized by two hitherto unnoticed pathogenetic changes in the cerebral cortex: (a) heterochronic decoupling of dendritic maturation within the same neuronal population (with some members significantly lagging behind the normal maturational schedule) and (b) anisotropically distorted shaping of dendritic trees, probably caused by patchy displacement of molecular guidance cues for dendrites in the malformed cortex. Copyright Georg Thieme Verlag KG Stuttgart New York.

  3. Decorin is one of the proteoglycans expressed in Walker 256 rat mammary carcinoma

    Directory of Open Access Journals (Sweden)

    S.M. Oba-Shinjo

    2003-08-01

    Full Text Available Proteoglycan and glycosaminoglycan content was analyzed in a model of rat mammary carcinoma to study the roles of these compounds in tumorigenesis. Hyaluronic acid and proteoglycans bearing chondroitin and/or dermatan sulfate chains were detected in solid tumors obtained after subcutaneous inoculation of Walker 256 rat carcinoma cells. About 10% of sulfated glycosaminoglycan chains corresponded to heparan sulfate. The small leucine-rich proteoglycan, decorin, was identified as one of the proteoglycans, in addition to others of higher molecular weight, by cross-reaction with an antiserum raised against pig laryngeal decorin and by N-terminal amino acid sequencing. Decorin was separated from other proteoglycans by hydrophobic chromatography and its complete structure was determined. It has a molecular weight of about 85 kDa and a dermatan chain of 45 kDa with 4-sulfated disaccharides. After degradation of the glycosaminoglycan chain, three core proteins of different molecular weight (36, 46 and 56 kDa were identified. The presence of hyaluronic acid and decorin has been reported in a variety of tumors and tumor cells. In the Walker 256 mammary carcinoma model, hyaluronic acid may play an important role in tumor progression, since it provides a more hydrated extracellular matrix. On the other hand, decorin, which is expressed by stromal cells, represents a host defense response to tumor growth.

  4. Climatic changes inferred fron analyses of lake-sediment cores, Walker Lake, Nevada

    International Nuclear Information System (INIS)

    Yang, In Che.

    1989-01-01

    Organic and inorganic fractions of sediment collected from the bottom of Walker Lake, Nevada, have been dated by carbon-14 techniques. Sedimentation rates and the organic-carbon content of the sediment were correlated with climatic change. The cold climate between 25,000 and 21,000 years ago caused little runoff, snow accumulation on the mountains, and rapid substantial glacial advances; this period of cold climate resulted in a slow sedimentation rate (0.20 millimeter per year) and in a small organic-carbon content in the sediment. Also, organic-carbon accumulation rates in the lake during this period were slow. The most recent period of slow sedimentation rate and small organic-carbon content occurred between 10,000 and 5500 years ago, indicative of low lake stage and dry climatic conditions. This period of dry climate also was evidenced by dry conditions for Lake Lahontan in Nevada and Searles Lake in California, as cited in the literature. Walker Lake filled rapidly with water between 5500 and 4500 years ago. The data published in this report was not produced under an approved Site Investigation Plan (SIP) or Study Plan (SP) and will not be used in the licensing process. 10 refs., 3 figs., 2 tabs

  5. Dandy-Walker syndrome in adult mimicking myasthenia gravis Síndrome de Dandy-Walker em adulto simulando miastenia gravis

    Directory of Open Access Journals (Sweden)

    Juliana Cardoso

    2007-03-01

    Full Text Available The Dandy-Walker syndrome (DWS is a rare posterior fossa malformation. The DWS can occur associated with other brain or systemic malformations, but ocular abnormalities in this disease are rare and clinical findings mimicking myasthenia gravis have not been described to date. We report a 23-year-old woman who presented mild limitation of the ocular movements with progressive palpebral ptosis, which changed in intensity during the day. The investigation showed negative anti-acetylcholine receptor antibody, repetitive nerve stimulation and "Tensilon test", but the brain magnetic resonance image reveals DWS with hydrocephalus associated with calosal dysgenesis. The characteristic of disease, clinical manifestations and pathologic features, specially the clinical evaluation of ocular abnormalities in suspicion of DWS, including the MG in differential diagnosis are discussed.A síndrome de Dandy-Walker (DWS é uma rara malformação da fossa posterior que pode ocorrer associada com outras malformações cerebrais ou sistêmicas. As alterações oculares são raras e as manifestações clínicas, simulando miastenia gravis (MG, não foram descritas até o momento. Descrevemos uma mulher de 23 anos apresentando discreta limitação da movimentação ocular com progressiva ptose palpebral que mudava de intensidade durante o dia. A investigação mostrou negativos o anticorpo anti-receptor de acetilcolina, a estimulação nervosa repetitiva e o "teste do Tensilon", porém a ressonância magnética de crânio revelou DWS com hidrocefalia associada à disgenesia de corpo caloso. As características da doença, manifestações clínicas e patológicas, especialmente a avaliação clínica de anormalidade ocular na suspeita de DWS serão discutidas, incluindo a MG no diagnóstico diferencial.

  6. The Dirac equation and the normalization of its solutions in a closed Friedmann- Robertson-Walker universe

    Science.gov (United States)

    Finster, Felix; Reintjes, Moritz

    2009-05-01

    We set up the Dirac equation in a Friedmann-Robertson-Walker geometry and separate the spatial and time variables. In the case of a closed universe, the spatial dependence is solved explicitly, giving rise to a discrete set of solutions. We compute the probability integral and analyze a spacetime normalization integral. This analysis allows us to introduce the fermionic projector in a closed Friedmann-Robertson-Walker geometry and to specify its global normalization as well as its local form. First author supported in part by the Deutsche Forschungsgemeinschaft.

  7. Risks of vaginal breech delivery at term compared with elective cesarean section - reply to comments by Walker and Powell, and Sholapurkar

    NARCIS (Netherlands)

    Vlemmix, Floortje; Mol, Ben Willem; Kok, Marjolein

    2015-01-01

    We thank both Walker and Powell (1), as well as Sholapurkar (2) for their interest in our work. Walker and Powell note that the risk of neonatal mortality for planned vaginal breech delivery (VBD) in our study is lower than the mortality reported in the term breech trial and comparable to the risk

  8. Los Chalcidoidea (Hymenoptera asociados con agallas de Cinípidos (Hymenoptera, Cynipidae en la Comunidad de Madrid

    Directory of Open Access Journals (Sweden)

    Gómez, J. F.

    2006-05-01

    Full Text Available Information about the chalcid wasp parasitoid community (Hymenoptera, Chalcidoidea associated with galls of Cynipidae in Madrid (Spain is compiled and updated. Studied material includes more than 1000 published and unpublished records from samplings in 80 sites in the Madrid region carried out over twenty three years by the research team. A check-list of 121 species, 19 of them provisionally identified, from 6 families of Chalcidoidea is provided as follows: 26 Eurytomidae, 27 Torymidae, 9 Ormyridae, 33 Pteromalidae, 9 Eupelmidae and 17 Eulophidae. Ormyrus rufimanus Mayr, 1904 and Idiomacromerus semiaeneus (Szelenyi, 1957 are recorded for the first time in the Iberian Peninsula. For each family and genus of Chalcidoidea data are given on biology, diversity and distribution in Comunidad de Madrid. The composition of the chalcid wasp parasitoid community associated with gall wasps in Comunidad de Madrid is discussed and compared to the same community data from the Iberian Peninsula and the Western Palaearctic. Species from the Iberian community of chalcid parasitoids that are missing from Madrid region, exclusive species and potentially present species are also commented upon. Finally two appendices are presented as follows: a list of the Chalcidoidea species reared from 73 different galls made by 71 cynipid species from Madrid with associated parasitoid records, and a final appendix with full record data of all studied material, including information on the sampling localities with X, Y georeferenced coordinates, host galls and host plants.

    Se compila y actualiza la información existente sobre la comunidad parasitoide de Chalcidoidea, asociada a agallas de cinípidos (Hymenoptera, Cynipidae en la Comunidad de Madrid. Los datos corresponden a más de 1000 registros, tanto de datos publicados, como inéditos, correspondientes a colectas en 80 localidades de Madrid efectuadas por el equipo investigador a lo largo de 23 a

  9. Partial cytochrome b sequences for six Hymenoptera of the eastern United States.

    Science.gov (United States)

    Collins, A M; Gardner, L M

    2001-01-01

    Mitochondrial DNA (mtDNA) haplotypes have been commonly used to determine honeybee subspecies relationships. To see if these markers would also be useful for comparisons of other Hymenoptera, we collected workers of six local species: Vespa crabro, the European hornet; Bombus impatiens, a bumblebee; Vespula germanica, the German yellow jacket; Polistes fuscatus, a paper wasp; Halictus ligatus, an alkali bee; and an unspecified Megachile, a leafcutting bee. MtDNA was isolated and digested with six endonucleases (AvaI, BglII, EcoRI, HindIII, HinfI, XbaI). The digested DNA was electrophoresed and visualized on agarose gels with comparison to a standard fragment marker and similarly treated honeybee mtDNA. The fragments obtained were also purified and sequenced. Phylogenetic relationships between six wasp and bee species, Apis mellifera, and several other similar aculeate Hymenoptera were determined. Newly defined DNA sequences were posted to GenBank (AF281169-AF281174).

  10. Ichneumonidae (Hymenoptera) parasitóides de larvas de Lepidoptera associadas a Croton floribundus Spreng (Euphorbiaceae)

    OpenAIRE

    Fernandes, Luciana Bueno dos Reis; Dias Filho, Manoel Martins; Fernandes, Marcelo Adorna; Penteado-Dias, Angelica Maria

    2010-01-01

    Parasitoids of the family Ichneumonidae (Hymenoptera) were obtained during an inventory of Lepidoptera larvae caught feeding in the wild on Croton floribundus (Euphorbiaceae). The Lepidoptera larvae were collected from host plants along trails inside three preserved forest areas in the Brazilian state of São Paulo. Fifteen different species of Ichneumonidae belonging to five subfamilies (Banchinae, Campopleginae, Cremastinae, Mesochorinae and Metopiinae) were obtained. Seven species of Ichneu...

  11. A Gynandromorph and Teratological Case in Spilomicrus sp. (Hymenoptera, Diaprioidea, Diapriidae

    Directory of Open Access Journals (Sweden)

    Emerson Comério

    2015-12-01

    Resumo. Este estudo relata a ocorrência de antenas com características femininas e masculinas em um exemplar fêmea de Spilomicrus sp. (Hymenoptera, Diaprioidea, Diapriidae coletado no Parque Estadual Intervales, Ribeirão Grande, São Paulo, Brasil, assim como malformações em uma das antenas, que são aqui descritas e ilustradas.

  12. Morphology and function of the ovipositor mechanism in Ceraphronoidea (Hymenoptera, Apocrita

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    Andrew Ernst

    2013-08-01

    Full Text Available The ovipositor of apocritan Hymenoptera is an invaluable source of phylogenetically relevant characters, and our understanding of its functional morphology stands to enlighten us about parasitoid life history strategies. Although Ceraphronoidea is one of the most commonly collected Hymenoptera taxa with considerable economic importance, our knowledge about their natural history and phylogenetic relationships, both to other apocritan lineages and within the superfamily itself, is limited. As a first step towards revealing ceraphronoid natural diversity we describe the skeletomuscular system of the ceraphronoid ovipositor for the first time. Dissections and Confocal Laser Scanning Microscopy 3D media files were used to visualize the ovipositor complex and to develop character concepts. Morphological structures were described in natural language and then translated into a character-character state format, whose terminology was linked to phenotype-relevant ontologies. Four unique anatomical phenotypes were revealed: 1. The first valvifer (gonangulum of the genus Trassedia is composed of two articulating sclerites, a condition present only in a few basal insect taxa. The bipartition of the first valvifer in Trassedia is most likely secondary and might allow more rapid oviposition. 2. Ceraphronoids, unlike other Hymenoptera, lack the retractor muscle of the terebra; instead the egg laying device is retracted by the seventh sternite. 3. Also unlike other Hymenoptera, the cordate apodeme and the anterior flange of the second valvifer are fused and compose one ridge that serves as the site of attachment for the dorsal and ventral T9-second valvifer muscles. Overall, the ceraphronoid ovipositor system is highly variable and can be described by discrete, distinguishable character states. However, these differences, despite their discrete nature, do not reflect the present classification of the superfamily and might represent parallelisms driven by host

  13. Identification of microsatellite markers for a worldwide distibuted, highly invasive ant species Tapinoma melanocephalum (Hymenoptera: Formicidiae)

    Czech Academy of Sciences Publication Activity Database

    Zima, Jan; Lebrasseur, O.; Borovanská, Michaela; Janda, Milan

    2016-01-01

    Roč. 113, JUNE 03 (2016), s. 409-414 E-ISSN 1802-8829 R&D Projects: GA ČR GAP505/12/2467 Grant - others:Marie Curie Fellowship(CZ) PIOFGA2009-25448 Institutional support: RVO:60077344 Keywords : Hymenoptera * Formicidae * Tapinoma melanocephalum Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.167, year: 2016 http://www.eje.cz/pdfs/eje/2016/01/53.pdf

  14. Accelerated evolution of mitochondrial but not nuclear genomes of Hymenoptera: new evidence from crabronid wasps.

    Directory of Open Access Journals (Sweden)

    Martin Kaltenpoth

    Full Text Available Mitochondrial genes in animals are especially useful as molecular markers for the reconstruction of phylogenies among closely related taxa, due to the generally high substitution rates. Several insect orders, notably Hymenoptera and Phthiraptera, show exceptionally high rates of mitochondrial molecular evolution, which has been attributed to the parasitic lifestyle of current or ancestral members of these taxa. Parasitism has been hypothesized to entail frequent population bottlenecks that increase rates of molecular evolution by reducing the efficiency of purifying selection. This effect should result in elevated substitution rates of both nuclear and mitochondrial genes, but to date no extensive comparative study has tested this hypothesis in insects. Here we report the mitochondrial genome of a crabronid wasp, the European beewolf (Philanthus triangulum, Hymenoptera, Crabronidae, and we use it to compare evolutionary rates among the four largest holometabolous insect orders (Coleoptera, Diptera, Hymenoptera, Lepidoptera based on phylogenies reconstructed with whole mitochondrial genomes as well as four single-copy nuclear genes (18S rRNA, arginine kinase, wingless, phosphoenolpyruvate carboxykinase. The mt-genome of P. triangulum is 16,029 bp in size with a mean A+T content of 83.6%, and it encodes the 37 genes typically found in arthropod mt genomes (13 protein-coding, 22 tRNA, and two rRNA genes. Five translocations of tRNA genes were discovered relative to the putative ancestral genome arrangement in insects, and the unusual start codon TTG was predicted for cox2. Phylogenetic analyses revealed significantly longer branches leading to the apocritan Hymenoptera as well as the Orussoidea, to a lesser extent the Cephoidea, and, possibly, the Tenthredinoidea than any of the other holometabolous insect orders for all mitochondrial but none of the four nuclear genes tested. Thus, our results suggest that the ancestral parasitic lifestyle of

  15. Phylogeny and population genetic structure of ant genus Acropyga (Hymenoptera: Formicidae) in Papua New Guinea

    Czech Academy of Sciences Publication Activity Database

    Janda, Milan; Matos Maravi, Pavel F.; Borovanská, Michaela; Zima, Jan; Youngerman, E.; Pierce, N. E.

    2016-01-01

    Roč. 30, č. 1 (2016), s. 28-40 ISSN 1445-5226 R&D Projects: GA ČR GAP505/12/2467 Grant - others:Marie Curie Fellowship(CZ) PIOFGA2009-25448; Operational Program Research and Development for Innovations(CZ) CZ.1.05/3.2.00/08.0144 Institutional support: RVO:60077344 Keywords : Acropyga * Hymenoptera * Papua New Guinea Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.172, year: 2016

  16. Meteorus arizonensis Muesebeck, 1923 (Hymenoptera: Braconidae): nuevo registro para México

    OpenAIRE

    Gutiérrez-Ramírez, A.; Robles-Bermúdez, A.; Cambero-Campos, J.; Coronado-Blanco, J. M.

    2015-01-01

    Braconidae is one of the more diverse families of Hymenoptera with almost 20,000 species worldwide. Meteorus has 316 species and is almost cosmopolitan. Previously, seven species of this genus have been recorded from Mexico. In this note, Meteorus arizo-nensis Muesebeck is recorded for the first time for the country, obtained from the fall armyworm, Spodoptera frugiperda (J.E. Smith), with material from Santa Maria del Oro, locality in the State of Nayarit.

  17. Can the Understory Affect the Hymenoptera Parasitoids in a Eucalyptus Plantation?

    Directory of Open Access Journals (Sweden)

    Onice Teresinha Dall'Oglio

    Full Text Available The understory in forest plantations can increase richness and diversity of natural enemies due to greater plant species richness. The objective of this study was to test the hypothesis that the presence of the understory and climatic season in the region (wet or dry can increase the richness and abundance of Hymenoptera parasitoids in Eucalyptus plantations, in the municipality of Belo Oriente, Minas Gerais State, Brazil. In each eucalyptus cultivation (five areas of cultivation ten Malaise traps were installed, five with the understory and five without it. A total of 9,639 individuals from 30 families of the Hymenoptera parasitoids were collected, with Mymaridae, Scelionidae, Encyrtidae and Braconidae being the most collected ones with 4,934, 1,212, 619 and 612 individuals, respectively. The eucalyptus stands with and without the understory showed percentage of individuals 45.65% and 54.35% collected, respectively. The understory did not represent a positive effect on the overall abundance of the individuals Hymenoptera in the E. grandis stands, but rather exerted a positive effect on the specific families of the parasitoids of this order.

  18. Can the Understory Affect the Hymenoptera Parasitoids in a Eucalyptus Plantation?

    Science.gov (United States)

    Dall’Oglio, Onice Teresinha; Ribeiro, Rafael Coelho; Ramalho, Francisco de Souza; Fernandes, Flávio Lemes; Wilcken, Carlos Frederico; de Assis Júnior, Sebastião Lourenço; Rueda, Rosa Angélica Plata; Serrão, José Eduardo; Zanuncio, José Cola

    2016-01-01

    The understory in forest plantations can increase richness and diversity of natural enemies due to greater plant species richness. The objective of this study was to test the hypothesis that the presence of the understory and climatic season in the region (wet or dry) can increase the richness and abundance of Hymenoptera parasitoids in Eucalyptus plantations, in the municipality of Belo Oriente, Minas Gerais State, Brazil. In each eucalyptus cultivation (five areas of cultivation) ten Malaise traps were installed, five with the understory and five without it. A total of 9,639 individuals from 30 families of the Hymenoptera parasitoids were collected, with Mymaridae, Scelionidae, Encyrtidae and Braconidae being the most collected ones with 4,934, 1,212, 619 and 612 individuals, respectively. The eucalyptus stands with and without the understory showed percentage of individuals 45.65% and 54.35% collected, respectively. The understory did not represent a positive effect on the overall abundance of the individuals Hymenoptera in the E. grandis stands, but rather exerted a positive effect on the specific families of the parasitoids of this order. PMID:26954578

  19. "It's Not so Much a Job but a Relationship": A Response to Romer and Walker

    Science.gov (United States)

    O'Brien, John

    2013-01-01

    Romer and Walker's "Appreciative Inquiry," which obtained input from 16 capable personal assistants, challenges some influential assumptions about personal assistance and opens a way to think about the demanding work of developing capable and committed personal assistants. Attempts to depersonalize the relationship between people…

  20. Neuropsychological and Behavioural Phenotype of Dandy-Walker Variant Presenting in Chromosome 22 Trisomy: A Case Study

    Science.gov (United States)

    Searson, Ruth; Hare, Dougal Julian; Sridharan, Sridhar

    2013-01-01

    In this study, a case of Dandy-Walker variant syndrome associated with trisomy 22 in a 17-year-old man is described. This is the first account of this combination in a person surviving into adulthood, and the neuropsychological and behavioural presentation is described in detail and a clinical formulation is presented for the benefit of…

  1. Case 3724 - Metochus abbreviatus Scott, 1874 (Insecta, Heteroptera): proposed precedence over Rhyparochromus erosus Walker, 1872 (currently Metochus erosus)

    Science.gov (United States)

    The purpose of this application, under Article 23.9.3 of the Code, is to conserve the widely used specific name Metochus abbreviatus Scott, 1874, for a species of rhyparochromid bugs from East Asia. The name is threatened by the senior subjective synonym Metochus erosus (Walker, 1872), which has bee...

  2. Effect of Walker A mutation (K86M) on oligomerization and surface targeting of the multidrug resistance transporter ABCG2

    DEFF Research Database (Denmark)

    Henriksen, Ulla Birk; Gether, Ulrik; Litman, Thomas

    2005-01-01

    The ATP binding cassette (ABC) half-transporter ABCG2 (MXR/BCRP/ABCP) is associated with mitoxantrone resistance accompanied by cross-resistance to a broad spectrum of cytotoxic drugs. Here we investigate the functional consequences of mutating a highly conserved lysine in the Walker A motif...

  3. Comparing Arc-shaped Feet and Rigid Ankles with Flat Feet and Compliant Ankles for a Dynamic Walker

    DEFF Research Database (Denmark)

    Kuhlemann, Ilyas; Matthias Braun, Jan; Wörgötter, Florentin

    2014-01-01

    In this paper we show that exchanging curved feet and rigid ankles by at feet and compliant ankles improves the range of gait parameters for a bipedal dynamic walker. The new lower legs were designed such that they t to the old set-up, allowing for a direct and quantitative comparison. The dynamic...

  4. Changes in Energy Cost and Total External Work of Muscles in Elite Race Walkers Walking at Different Speeds

    Directory of Open Access Journals (Sweden)

    Chwała Wiesław

    2014-12-01

    Full Text Available The aim of the study was to assess energy cost and total external work (total energy depending on the speed of race walking. Another objective was to determine the contribution of external work to total energy cost of walking at technical, threshold and racing speed in elite competitive race walkers.

  5. Description of a new species and subspecies of Idalus Walker from Costa Rica, Honduras and Guatemala (Lepidoptera, Erebidae, Arctiinae, Arctiini)

    Science.gov (United States)

    Espinoza, Bernardo A.; Janzen, Daniel H.; Winnie Hallwachs;  J. Bolling Sullivan

    2013-01-01

    Abstract A new species and subspecies of Idalus Walker are described from Costa Rica, Honduras and Guatemala. Images of males and females and their genitalia are provided. Locality information and distribution maps for Costa Rica and for Guatemala are included. The biology and phylogeny of Idalus are discussed. PMID:23730178

  6. Quantum features derived from the classical model of a bouncer-walker coupled to a zero-point field

    International Nuclear Information System (INIS)

    Schwabl, H; Mesa Pascasio, J; Fussy, S; Grössing, G

    2012-01-01

    In our bouncer-walker model a quantum is a nonequilibrium steady-state maintained by a permanent throughput of energy. Specifically, we consider a 'particle' as a bouncer whose oscillations are phase-locked with those of the energy-momentum reservoir of the zero-point field (ZPF), and we combine this with the random-walk model of the walker, again driven by the ZPF. Starting with this classical toy model of the bouncer-walker we were able to derive fundamental elements of quantum theory. Here this toy model is revisited with special emphasis on the mechanism of emergence. Especially the derivation of the total energy hω o and the coupling to the ZPF are clarified. For this we make use of a sub-quantum equipartition theorem. It can further be shown that the couplings of both bouncer and walker to the ZPF are identical. Then we follow this path in accordance with Ref. [2], expanding the view from the particle in its rest frame to a particle in motion. The basic features of ballistic diffusion are derived, especially the diffusion constant D, thus providing a missing link between the different approaches of our previous works.

  7. Dandy-walker malformation and the contribution of radioisotopic studies of cerebral spinal fluid dynamics to its diagnosis

    International Nuclear Information System (INIS)

    Palma, A.; Nazar, N.; Castro, M.; Olea, E.; Guzmann, G.

    1982-01-01

    On case of Dandy-Walker malformation is described. The diagnosis was mainly reached by dynamic isotope studies of CSF, and was confirmed by axial computerized tomography. The importance of these examinations is discussed, not only as a means of understanding the aetiopathology, but especially because of the functional information they give and the therapeutic consequences they have. (Author)

  8. 75 FR 19880 - Safety Zone; BW PIONEER at Walker Ridge 249, Outer Continental Shelf FPSO, Gulf of Mexico

    Science.gov (United States)

    2010-04-16

    ... BW PIONEER, a Floating Production, Storage and Offloading (FPSO) system, at Walker Ridge 249 in the Outer Continental Shelf. The purpose of the safety zone is to protect the FPSO from vessels operating... reduces the threat of allisions, oil spills, and releases of natural gas, and thereby protects the safety...

  9. Effect of entomopathogens on Africanized Apis mellifera L. (Hymenoptera: Apidae

    Directory of Open Access Journals (Sweden)

    Michele Potrich

    2018-01-01

    Full Text Available This study aimed to evaluate the effect of commercially used entomopathogens on Africanized Apis mellifera L. (Hymenoptera: Apidae. Four bioassays were performed: 1 pulverized entomopathogens on A. mellifera; 2 entomopathogens sprayed on a smooth surface; 3 entomopathogens sprayed on soy leaves; and 4 entomopathogens mixed with candy paste (sugar syrup. Five treatments were prepared: sterile distilled water (control, distilled water sterilized with Tween® 80 (0.01%, and the commercial entomopathogens Metarhizium anisopliae E9 (1.0 × 109 conidia mL−1, Beauveria bassiana PL63 (1.0 × 108 conidia mL−1 and Bacillus thuringiensis var. kurstaki HD-1 (3.0 × 108 spores mL−1. Each treatment consisted of five repetitions, with 20 workers per repetition, which were stored in a plastic box and, later, in a biological oxygen demand (B.O.D. incubator (27 ± 2 °C, RH of 60% ± 10%, 12-h photophase. The mortality of the workers was evaluated from 1 h to 240 h, and the data were analyzed using Bayesian inference. The workers killed by the ingestion of candy paste contaminated with the pathogens (products were randomly separated and selected for the removal of the midgut. Each midgut was fixed in Bouin's solution and prepared for histology. B. bassiana was verified to reduce the survival of A. mellifera workers in all bioassays. Moreover, M. anisopliae reduced the survival of A. mellifera workers directly sprayed, on a smooth surface and mixed with candy. B. thuringiensis reduced A. mellifera survival on a smooth surface and mixed with candy paste. However, its effects were lower than that observed by B. bassiana. The treatments with the biological products did not induce morphometric alterations in the midgut of A. mellifera. Keywords: Bayesian statistics, Entomopathogenic fungi, Entomopathogenic bacteria, Honeybee, Selectivity

  10. A new species of Crinibracon Quicke (Hymenoptera: Braconidae) parasitic on pupae of Hasora chromus (Cramer) (Lepidoptera: Hesperiidae) from India.

    Science.gov (United States)

    Gupta, Ankita; Achterberg, Cornelis Van; Chitrala, Malathi

    2016-08-29

    A new species, Crinibracon chromusae Gupta & van Achterberg sp. n., parasitic on pupae of Hasora chromus (Cramer) (Hesperiidae) on Millettia (= Pongamia) pinnata (L.) Panigrahi (Fabaceae), is described from India and compared with C. sinicus (Yang, Chen & Liu, 2008) from China, the only other species known with a similar general appearance. For the first time biological information for the genus Crinibracon Quicke, 1988, is given. Three species of hyperparasitoids, Philolema braconidis (Ferrière) (Hymenoptera: Eurytomidae), Nesolynx javanica Ferrière (Hymenoptera: Eulophidae), and an Eupelmus sp. (Hymenoptera: Eupelmidae) emerged along with C. chromusae sp. n. from pupae of H. chromus. The generic placement of this new species along with interesting parasitoid biology is discussed.

  11. The development of a radioimmunological assay for parathormone formed from the hypercalcemic Walker carcinosarcoma 256

    International Nuclear Information System (INIS)

    Weise, D.

    1981-01-01

    Specific antibodies to Walker Carcinosomal tissue could be produced by immunizing goats with a hypercalcemically active extract of this tumor tissue. These served the stablishment of a radioimmunoassay. The tracer used was 125-iodine labelled borine parathormone. Various parathormone standards were measured in this system. Here it was found that with this new system a specific assay had been developed which measures immunoreactive parathormone. Preliminary serum analyses indicated that endogenous human parathormone is also detected by this new radioimmunoassay. On the basis of comparative measurements with the old antibody directed towards human extractive parathormone and the new antibody for tumor parathormone only limited conclusions are possible. It could, however, be shown that the new antibody is an anti-parathormone-antibody. (orig./MG) [de

  12. Interactions of ozone and antineoplastic drugs on rat lung fibroblasts and Walker rat carcinoma cells

    International Nuclear Information System (INIS)

    Wenzel, D.G.; Morgan, D.L.

    1983-01-01

    Cultured rat lung fibroblasts (F-cells) and Walker rat carcinoma cells (WRC-cells) labeled with 51 Cr were exposed to the following antitumor drugs alone or with O 3 : carmustine (BCNU), doxorubicin (Dox), cisplatin (CPt), mitomycin C (Mit C) or vitamin K 3 (Vit K). Release of 51 Cr (cell injury) was greater for F-cells than WRC-cells with any single treatment. Pretreatment with any drug (400 microM), except for Vit K with WRC-cells, did not significantly increase O 3 -induced loss of 51 Cr. Co-exposure of F-cells to drugs and O 3 resulted in a marked potentiation of O 3 -induced injury with Vit K, and an inhibition with Dox

  13. Path tracking control of an omni-directional walker considering pressures from a user.

    Science.gov (United States)

    Tan, Renpeng; Wang, Shuoyu; Jiang, Yinlai; Ishida, Kenji; Fujie, Masakatsu G

    2013-01-01

    An omni-directional walker (ODW) is being developed to support the people with walking disabilities to do walking rehabilitation. The training paths, which the user follows in the rehabilitation, are defined by physical therapists and stored in the ODW. In order to obtain a good training effect, the defined training paths need to be performed accurately. However, the ODW deviates from the training path in real rehabilitation, which is caused by the variation of the whole system's parameters due to the force from the user. In this paper, the characteristics of pressures from a user are measured, based on which an adaptive controller is proposed to deal with this problem, and validated in an experiment in which a pseudo handicapped person follows the ODW. The experimental results show that the proposed method can control the ODW to accurately follow the defined path with or without a user.

  14. "It feels good to be measured": clinical role-play, Walker Percy, and the tingles.

    Science.gov (United States)

    Ahuja, Nitin K

    2013-01-01

    A large online community has recently formed around autonomous sensory meridian response (ASMR), a pleasant and poorly understood somatic reaction to specific interpersonal triggers. Its web-based manifestations include a variety of amateur videos designed to elicit the reaction, many of which feature protracted imitations of a clinician's physical exam. This analysis considers through a literary lens the proximity of this phenomenon to clinical diagnostics, focusing in particular on characterizations of spiritual isolation elaborated in Love in the Ruins (1971), the third novel by physician-writer Walker Percy (1916-1990). Within this speculative framework, the tendency to derive pleasure from clinical milieus, real or constructed, may be interpreted as a quality particular to the postmodern psyche. Viewing web-based clinical role-play in light of Percy's writing also underscores the possibility that routine diagnostic assessments may have independent therapeutic implications.

  15. NMR images of non-communicating hydrocephalus associated with Dandy-Walker variant and achondroplasia

    International Nuclear Information System (INIS)

    Sato, Masaharu; Kuroda, Ryotaro; Watanabe, Masaru; Nakatani, Jiro; Ioku, Masahiko; Irisawa, Minoru; Hamada, Tatsumi; Ishida, Osamu

    1988-01-01

    Two cases of non-communicating hydrocephalus caused by a relatively rare etiology were reported. They were both diagnosed by means of nuclear magnetic resonance (NMR). The first patient, a 4-month-old boy, had Dandy-Walker variant, showing hypoplasia of the corpus callosum and the inferior vermis, and a large cyst behind the vermis, communicating with the subarachnoid space, as well as hydrocephalus; the fourth ventricle was partially reserved. The second patient, also a 4-month-old boy, had achondroplasia, resulting in a narrow foramen magnum; the disturbance of the outflow of the cerebro-spinal fluid around the cisterna magna was thought to be the cause of hydrocephalus in his case. The validity of NMR was demonstrated in the diagnoses of these conditions, for a high resolution was needed in examining the complicated structure of the posterior fossa. (author)

  16. NMR images of non-communicating hydrocephalus associated with Dandy-Walker variant and achondroplasia

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Masaharu; Kuroda, Ryotaro; Watanabe, Masaru; Nakatani, Jiro; Ioku, Masahiko; Irisawa, Minoru; Hamada, Tatsumi; Ishida, Osamu

    1988-06-01

    Two cases of non-communicating hydrocephalus caused by a relatively rare etiology were reported. They were both diagnosed by means of nuclear magnetic resonance (NMR). The first patient, a 4-month-old boy, had Dandy-Walker variant, showing hypoplasia of the corpus callosum and the inferior vermis, and a large cyst behind the vermis, communicating with the subarachnoid space, as well as hydrocephalus; the fourth ventricle was partially reserved. The second patient, also a 4-month-old boy, had achondroplasia, resulting in a narrow foramen magnum; the disturbance of the outflow of the cerebro-spinal fluid around the cisterna magna was thought to be the cause of hydrocephalus in his case. The validity of NMR was demonstrated in the diagnoses of these conditions, for a high resolution was needed in examining the complicated structure of the posterior fossa.

  17. Irradiation of solid Walker carcino-sarcomas after synchronisation with hydroxyurea

    International Nuclear Information System (INIS)

    Wayss, K.; Mattern, J.; Volm, M.

    1980-01-01

    Sprague-Dawley rats with solid Walker carcino-sarcomas were synchronized with hydroxyurea (HU; 6 x 50 mg and 1 x 300 mg HU/kg body weight) and then irradiated at different time points ( 60 Co). The synchronized tumors showed a significant delay of growth when irradiation was applied in the late G1 phase, at the transition G1/S and in the early S phase. The remaining phases of the cell cycle, especially the S phase showed the same sensitivity as the non-synchronized controls. Improvement of therapy by irradiation after HU application was largely due to the synchronization of tumor cells. Only the increased therapeutic effect of irradiation shortly after application of HU can be explained also by combination of both HU and irradiation. (orig.) 891 MG/orig. 892 MKO [de

  18. On the integrability of Friedmann-Robertson-Walker models with conformally coupled massive scalar fields

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, L A A [Programa de Pos-Graduacao em Fisica, Universidade do Estado do Rio de Janeiro, Rua Sao Francisco Xavier 524, Maracana, Rio de Janeiro, RJ, 20550-900 (Brazil); Skea, J E F [Departamento de Fisica Teorica, Instituto de Fisica, Universidade do Estado do Rio de Janeiro, Rua Sao Francisco Xavier 524, Maracana, Rio de Janeiro, RJ, 20550-900 (Brazil); Stuchi, T J [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68528, Rio de Janeiro, RJ, 21945-970 (Brazil)], E-mail: luis@dft.if.uerj.br, E-mail: jimsk@dft.if.uerj.br, E-mail: tstuchi@if.ufrj.br

    2008-02-22

    In this paper, we use a nonintegrability theorem by Morales and Ramis to analyse the integrability of Friedmann-Robertson-Walker cosmological models with a conformally coupled massive scalar field. We answer the long-standing question of whether these models with a vanishing cosmological constant and non-self-interacting scalar field are integrable: by applying Kovacic's algorithm to the normal variational equations, we prove analytically and rigorously that these equations and, consequently, the Hamiltonians are nonintegrable. We then address the models with a self-interacting massive scalar field and cosmological constant and show that, with the exception of a set of measure zero, the models are nonintegrable. For the spatially curved cases, we prove that there are no additional integrable cases other than those identified in the previous work based on the non-rigorous Painleve analysis. In our study of the spatially flat model, we explicitly obtain a new possibly integrable case.

  19. Prissy’s Quittin’ Time: The Black Camp Aesthetics of Kara Walker

    Directory of Open Access Journals (Sweden)

    Stephens Brian

    2017-12-01

    Full Text Available Through a close reading of Walker’s first silhouette instalment-the audaciously titled Gone, An Historical Romance of a Civil War as it Occurred Between the Dusky Thighs of One Young Negress and Her Heart (1994-this article examines how Walker utilises black camp to undermine both white supremacist and restrictive black uplift discourse. To be sure, the article is not an attempt to conflate these two, for the former is powerfully worse than the latter. However, it is necessary to explore how both discourses reinforce essentialist articulations of blackness and also to examine how black camp is a provocative analytic for their simultaneous disruption. Camp is usually understood as a queer-derived cultural practice that inflates identity to expose the constructed nature of gender. However, this article shows that black articulations of camp inflate identity to demonstrate the fiction of race as well.

  20. Stability of geodesic imcompleteness for Robertson-Walker space-times

    International Nuclear Information System (INIS)

    Beem, J.K.

    1981-01-01

    Let (M,g) be a Lorentzian warped product space-time M = (a, b) X H,g = -dt 2 x fh, where -infinity -infinity and (H,h) is homogeneous, then the past incompleteness of every timelike geodesic of (M,g) is stable under small C 0 perturbations in the space Lor(M) of Lorentzian metrics for M. Also it is shown that if (H,h) is isotropic and (M,g) contains a past-inextendible, past-incomplete null geodesic, then the past incompleteness of all null geodesics is stable under small C 1 perturbations in Lor(M). Given either the isotropy or homogeneity of the Riemannian factor, the background space-time (M,g) is globally hyperbolic. The results of this paper, in particular, answer a question raised by D. Lerner for big bang Robertson-Walker cosmological models affirmatively. (author)

  1. Effects of field interactions upon particle creation in Robertson-Walker universes

    International Nuclear Information System (INIS)

    Birrell, N.D.; Davies, P.C.W.; Ford, L.H.

    1980-01-01

    Particle creation due to field interactions in an expanding Robertson-Walker universe is investigated. A model in which pseudoscalar mesons and photons are created as a result of their mutual interaction is considered, and the energy density of created particles is calculated in model universes which undergo a bounce at some maximum curvature. The free-field creation of non-conformally coupled scalar particles and of gravitons is calculated in the same space-times. It is found that if the bounce occurs at a sufficiently early time the interacting particle creation will dominate. This result may be traced to the fact that the model interaction chosen introduces a length scale which is much larger than the Planck length. (author)

  2. Comments on the Dirac field in Friedmann-Robertson-Walker spacetime

    International Nuclear Information System (INIS)

    Khanal, U.

    2006-12-01

    Some further consequences about the massive Dirac field in Friedmann-Robertson-Walker universe are drawn. The comoving momenta of the particles in a closed universe are found to be quantized in units of half-integer, half being the contribution of the spin. This suggests that a gravitationally trapped fermion will have its momentum quantized. Both the comoving particle number and energy density are found not to be conserved in any finite volume of the universe. There exists a finite current that tends to enhance the density contrast. A series solution for the temporal part is used to show this effect. The particles distribute themselves in such a way as to resemble that required for the flattened rotation curves of galaxies. Although the total energy current grows with r, it is found that the current density, through unit area, goes down after attaining a peak. (author)

  3. Effects of Walker 256 carcinoma on metabolic alterations during the evolution of pregnancy.

    Science.gov (United States)

    Cintra-Gomes, M C; Cury, L; Parreira, M R; Elias, C F; Areas, M A

    1990-01-01

    The control of pregnant cancer patients is difficult because it involves both mother and fetus, and the metabolic alterations in the cancer host induce a massive mobilization of nutrients diverted to the neoplastic cells. The purpose of the present study was to determine the evolution of the Walker 256 carcinoma in pregnant rats and its consequences on fetal development. The results showed that the tumors displayed a very rapid rate of growth and induced a reduction in fetal weights in the pregnant tumor-bearing rats. The tumor-bearing and pregnant tumor-bearing groups showed a decrease in blood glucose and total serum protein, suggesting an increase in energy utilization of these substrates and synthetic activity by the tumoral cells. An imbalance between protein synthesis and catabolism may occur in the tumor-bearing rats which may be related to the degree of nutritional depletion.

  4. Vaidya--Patel solution with Robertson--Walker metric as a rotating inflationary scenario

    International Nuclear Information System (INIS)

    Groen, O.; Soleng, H.H.

    1988-01-01

    The Vaidya--Patel solution of a rotating homogeneous fluid in the presence of a Maxwellian source-free electromagnetic field is interpretated as an inflationary scenario with a gauge field with local U(1) symmetry, a vacuum energy, and a rotating perfect fluid. An explicit solution is found to be expressible in terms of known solutions representing the radiation filled Robertson--Walker universe with a cosmological term. In the case that the rotating fluid is radiation, the discussion of the model is considerably simplified. How the time scale of transition into a pseudo-de Sitter stage, as observed by an observer following the rotating fluid, is affected by vorticity is also studied

  5. Scanning Electron Microscopy Study of the Antennal Sensilla of Monema flavescens Walker (Lepidoptera: Limacodidae).

    Science.gov (United States)

    Yang, S; Liu, H; Zhang, J T; Liu, J; Zheng, H; Ren, Y

    2017-04-01

    Monema flavescens Walker (Lepidoptera: Limacodidae) is a serious polyphagous defoliator. Using scanning electron microscopy, the external morphology of the antennal sensilla of this pest was examined for a better understanding of the mechanisms of insect-insect and insect-plant chemical communications. The antennae of M. flavescens were filiform in shape, and 11 morphological types of sensilla were found in both sexes. Six types of likely chemosensory sensilla were identified: uniporous sensilla chaetica, multiporous sensilla trichodea, and four types of multiporous sensilla basiconica. The sensilla identified as likely mechanoreceptors included two subtypes of aporous sensilla chaetica, aporous sensilla coeloconica, aporous sensilla styloconica, and Böhm's bristles, whereas the position of the antennae was monitored by Böhm's bristles.

  6. Walker Branch Throughfall Displacement Experiment Data Report: Site Characterization, System Performance, Weather, Species Composition, and Growth

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, P.J.

    2001-09-04

    This numeric data package provides data sets, and accompanying documentation, on site characterization, system performance, weather, species composition, and growth for the Throughfall Displacement Experiment, which was established in the Walker Branch Watershed of East Tennessee to provide data on the responses of forests to altered precipitation regimes. The specific data sets include soil water content and potential, coarse fraction of the soil profile, litter layer temperature, soil temperature, monthly weather, daily weather, hourly weather, species composition of trees and saplings, mature tree and sapling annual growth, and relative leaf area index. Fortran and SAS{trademark} access codes are provided to read the ASCII data files. The data files and this documentation are available without charge on a variety of media and via the Internet from the Carbon Dioxide Information Analysis Center (CDIAC).

  7. Changes of the lactate dehydrogenase in the tissue fraction with Walker carcinoma under irradiation

    International Nuclear Information System (INIS)

    Schultheis, W.

    1972-01-01

    The behaviour of LDH, GOT and GPT of one and the same tissue with and without irradiation treatment as a means of cancer diagnosis is presented. Parallel to this, the corresponding blood values are determined, and an agar-gel isoenzyme separation of the LDH is carried out. In the 11 day-old Walker carcinoma of the rat, total tumour LDH as well as total serum LDH are increased. The X-radiation does not affect the result. The M 4 isoenzyme is mainly found in the tumour tissue, to whose benefit the tumour sera also change. In tissue processing, LDH, GOT and GPT behave corresponding to their occurence in the cell compartments. The enzymes, however, appear to differ in their solution behaviour. X-radiation leeds to an early removal of these enzymes in the sense of an 'enzyme release'. (BSC/LH) [de

  8. Participation of the NO/cGMP/K+ATP pathway in the antinociception induced by Walker tumor bearing in rats

    International Nuclear Information System (INIS)

    Barbosa, A.L.R.; Pinheiro, C.A.; Oliveira, G.J.; Torres, J.N.L.; Moraes, M.O.; Ribeiro, R.A.; Vale, M.L.; Souza, M.H.L.P.

    2012-01-01

    Implantation of Walker 256 tumor decreases acute systemic inflammation in rats. Inflammatory hyperalgesia is one of the most important events of acute inflammation. The L-arginine/NO/cGMP/K + ATP pathway has been proposed as the mechanism of peripheral antinociception mediated by several drugs and physical exercise. The objective of this study was to investigate a possible involvement of the NO/cGMP/K + ATP pathway in antinociception induced in Walker 256 tumor-bearing male Wistar rats (180-220 g). The groups consisted of 5-6 animals. Mechanical inflammatory hypernociception was evaluated using an electronic version of the von Frey test. Walker tumor (4th and 7th day post-implantation) reduced prostaglandin E 2 - (PGE 2 , 400 ng/paw; 50 µL; intraplantar injection) and carrageenan-induced hypernociception (500 µg/paw; 100 µL; intraplantar injection). Walker tumor-induced analgesia was reversed (99.3% for carrageenan and 77.2% for PGE 2 ) by a selective inhibitor of nitric oxide synthase (L-NAME; 90 mg/kg, ip) and L-arginine (200 mg/kg, ip), which prevented (80% for carrageenan and 65% for PGE 2 ) the effect of L-NAME. Treatment with the soluble guanylyl cyclase inhibitor ODQ (100% for carrageenan and 95% for PGE 2 ; 8 µg/paw) and the ATP-sensitive K + channel (KATP) blocker glibenclamide (87.5% for carrageenan and 100% for PGE 2 ; 160 µg/paw) reversed the antinociceptive effect of tumor bearing in a statistically significant manner (P < 0.05). The present study confirmed an intrinsic peripheral antinociceptive effect of Walker tumor bearing in rats. This antinociceptive effect seemed to be mediated by activation of the NO/cGMP pathway followed by the opening of KATP channels

  9. “Ancestors We Didn’t Even Know We Had”: Alice Walker, Asian Religion, and Ethnic Authenticity

    Directory of Open Access Journals (Sweden)

    Kyle Garton-Gundling

    2015-03-01

    Full Text Available Recent debates about the ethics of identity in a global age have dealt with how to prioritize conflicting local and global allegiances. Guided by these concerns, the fiction of Alice Walker develops a distinctive view of how local cultures and global movements can fruitfully interact. This vision depends on concepts from Asian religions, a major influence that critics of Walker have largely overlooked. Walker promotes Hindu and Buddhist meditation in a context of widespread African American skepticism toward Asian religions. According to widespread notions of cultural authenticity, Asian religions cannot nourish an African American connection to ethnic roots. In response to this challenge, Alice Walker’s fiction portrays Hindu and Buddhist mystics as African Americans’ ancestors, thus positioning these faiths as authentically black. By creatively enfolding Asian religions into her sense of African American heritage, Walker builds a spiritual cosmopolitanism that relies on claims of ancestral affiliation even when these claims are not literal. This strategy is Walker’s effort to create a new paradigm of cultural authenticity, one that allows individuals and groups to choose their ancestors. Walker’s approach seeks to incorporate disparate global influences while still valorizing the figure of the ancestor. This innovative approach places Walker at the forefront of a growing number of African American artists and intellectuals who promote Asian religions to American minorities. Walker’s work vividly dramatizes larger concerns in transnational American Studies: Eastern philosophy’s relevance to identity politics, the tensions between universal ideals and cultural specifics, and the ethics of cross-cultural appropriation.

  10. Primer registro de Tremex fuscicornis (Hymenoptera: Siricidae para la Argentina en una plantación de álamos en Buenos Aires First record of Tremex fuscicornis (Hymenoptera: Siricidae in Argentina infesting a poplar plantation in Buenos Aires

    Directory of Open Access Journals (Sweden)

    Lucas Landi

    2011-12-01

    Full Text Available La presencia de la "avispa taladradora de las latifoliadas", Tremex fuscicornis Fabricius (Hymenoptera: Siricidae, fue detectada en una plantación de álamos de la provincia de Buenos Aires, lo que constituye el primer registro de la especie para la Argentina. Se describen aspectos morfológicos y biológicos de la misma.The presence of the woodwasp Tremex fuscicornis Fabricius (Hymenoptera: Siricidae was detected in a poplar plantation in Buenos Aires. This is the first record of the species in Argentina. Morphological and biological aspects of the woodwasp are described.

  11. A Kinematic Model for Vertical Axis Rotation within the Mina Deflection of the Walker Lane

    Science.gov (United States)

    Gledhill, T.; Pluhar, C. J.; Johnson, S. A.; Lindeman, J. R.; Petronis, M. S.

    2016-12-01

    The Mina Deflection, at the boundary between the Central and Southern Walker Lane, spans the California-Nevada border and includes a heavily-faulted Pliocene volcanic field overlying Miocene ignimbrites. The dextral Walker Lane accommodates 25% of relative Pacific-North America plate motion and steps right across the sinistral Mina deflection. Ours and previous work shows that the Mina Deflection partially accommodates deformation by vertical-axis rotation of up to 99.9o ± 6.1o rotation since 11 Ma. This rotation is evident in latite ignimbrite of Gilbert et al. (1971), which we have formalized as three members of Tuff of Huntoon Creek (THC). The welded, basal, normal-polarity Huntoon Valley Member of THC is overlain by the unwelded to partially-welded, reversed-polarity Adobe Hills Mbr. This member includes internal breaks suggesting multiple eruptive phases, but the paleomagnetic results from each are statistically indistinguishable, meaning that they were likely erupted in rapid succession (within a few centuries of one another). THC ends with a welded member exhibiting very shallow inclination and south declination that we call Excursional Mbr. One of the upper members has been dated at 11.17 ± 0.04 Ma. These Miocene units are overlain by Pliocene basalts, Quaternary alluvium, and lacustrine deposits. Our paleomagnetic results show a gradient between the zero rotation domain and high rotation across a 20km baseline. A micropolar model, based on 25 years of earthquake data from the Northern and Southern California Seismic Network, suggest the Mina Deflection is currently experiencing transpressional seismogenic deformation (Unruh et al., 2003). Accepting Unruh's model and assuming continuous rotation since 11 Ma, we propose a kinematic model for the western Mina Deflection that accommodates 90o of vertical axis rotation from N-S to ENE-WSW oriented blocks.

  12. Walker use, but not falls, is associated with lower physical functioning and health of residents in an assisted-living environment.

    Science.gov (United States)

    Andersen, Daniel A; Roos, Bernard A; Stanziano, Damian C; Gonzalez, Natasha M; Signorile, Joseph F

    2007-01-01

    The relationship between perceived health and walker use has seldom been addressed. Concerns over falls and falls risk are precursors to walker use. We compared the SF-36 scores of 26 women and 14 men, mean age 86.8 +/- 6.0 years based on walker use and faller status. An analysis of covariance (ANCOVA) with age as the covariate, compared groups for the SF-36 constructs and totals score. Significant differences were noted between walker users and nonusers in physical functioning, role limitations due to physical problems, general health, and the total SF-36 score. Pairwise comparisons favored nonusers, while no differences were seen due to faller status. Walker use is associated with lower self-perceptions of physical functioning, role limitations due to physical problems, and general health in assisted-living residents. Faller status is not associated with self-perceived health status. Although walker use aids mobility and lowers the probability of falls, further research is needed to determine if the prescription of assistive devices has a more negative impact on self-perceived health than does falling. This possibility could be explained, in part, by the greater activity levels of those individuals who do not depend on walkers.

  13. Diversidade de abelhas (Hymenoptera, Apidae) ao longo de um gradiente latitudinal na Mata Atlântica

    OpenAIRE

    Gonçalves,Rodrigo Barbosa; Brandão,Carlos Roberto Ferreira

    2008-01-01

    A Mata Atlântica é um dos ambientes mais ricos e ameaçados do mundo, o que deveria ter estimulado em muito o estudo e a conservação do Bioma, mas a fauna de Hymenoptera permanece ainda relativamente pouco conhecida. Em especial, a fauna de abelhas da floresta ombrófila densa é pouco estudada em comparação à fauna das áreas abertas brasileiras. O projeto temático "Biodiversidade de Hymenoptera e Isoptera: riqueza e diversidade ao longo de um gradiente latitudinal na Mata Atlântica - a floresta...

  14. Organic geochemistry and brine composition in Great Salt, Mono, and Walker Lakes

    Science.gov (United States)

    Domagalski, Joseph L.; Orem, W.H.; Eugster, H.P.

    1989-01-01

    Samples of Recent sediments, representing up to 1000 years of accumulation, were collected from three closed basin lakes (Mono Lake, CA, Walker Lake, NV, and Great Salt Lake, UT) to assess the effects of brine composition on the accumulation of total organic carbon, the concentration of dissolved organic carbon, humic acid structure and diagenesis, and trace metal complexation. The Great Salt Lake water column is a stratified Na-Mg-Cl-SO4 brine with low alkalinity. Algal debris is entrained in the high density (1.132-1.190 g/cc) bottom brines, and in this region maximum organic matter decomposition occurs by anaerobic processes, with sulfate ion as the terminal electron acceptor. Organic matter, below 5 cm of the sediment-water interface, degrades at a very slow rate in spite of very high pore-fluid sulfate levels. The organic carbon concentration stabilizes at 1.1 wt%. Mono Lake is an alkaline (Na-CO3-Cl-SO4) system. The water column is stratified, but the bottom brines are of lower density relative to the Great Salt Lake, and sedimentation of algal debris is rapid. Depletion of pore-fluid sulfate, near l m of core, results in a much higher accumulation of organic carbon, approximately 6 wt%. Walker Lake is also an alkaline system. The water column is not stratified, and decomposition of organic matter occurs by aerobic processes at the sediment-water interface and by anaerobic processes below. Total organic carbon and dissolved organic carbon concentrations in Walker Lake sediments vary with location and depth due to changes in input and pore-fluid sulfate concentrations. Nuclear magnetic resonance studies (13C) of humic substances and dissolved organic carbon provide information on the source of the Recent sedimentary organic carbon (aquatic vs. terrestrial), its relative state of decomposition, and its chemical structure. The spectra suggest an algal origin with little terrestrial signature at all three lakes. This is indicated by the ratio of aliphatic to

  15. The first record of the genus Tanaostigma (Hymenoptera: Tanaostigmatidae) in the Old World, with the description of a new species from India.

    Science.gov (United States)

    Gupta, Ankita; Joshi, Sunil

    2016-11-15

    Tanaostigma Howard (Hymenoptera: Tanaostigmatidae) is recorded for the first time in the fauna of the Old World, with T. indica Gupta sp. n.  described and illustrated from southern India, reared from Millettia (=Pongamia) pinnata (Fabaceae).

  16. Effects of feeding frequency and sugar concentration on behavior and longevity of the adult aphid parasitoid: Aphidius ervi (Haliday) (Hymenoptera: Braconidae)

    NARCIS (Netherlands)

    Azzouz, H.; Giordanengo, P.; Wäckers, F.L.; Kaiser, L.

    2004-01-01

    Aphidius ervi (Haliday) (Hymenoptera: Braconidae) is a solitary aphid endoparasitoid. Adults feed on honeydew and possibly on other sugar sources such as nectar. Sugar sources can vary qualitatively and quantitatively according to biotic factors and environmental conditions. Experiments were

  17. Oviposition behavior and survival of Tamarixia radiata (Hymenoptera: Eulophidae), an ectoparasitoid of the Asian citrus psyllid, Diaphorina citri (Hemiptera: Liviidae), on hosts exposed to an entomopathogenic fungus

    Science.gov (United States)

    Antagonistic interactions between the nymphal parasitoid, Tamarixia radiata Waterston (Hymenoptera: Eulophidae), and the ARSEF 3581 isolate of the entomopathogenic fungus, Isaria fumosorosea Wize (Hypocreales: Cordycipitaceae) could disrupt biological control of the Asian citrus psyllid, Diaphorina ...

  18. WATER TEMPERATURE and other data from USS WALKER from 1991-07-01 to 1991-07-10 (NODC Accession 9100147)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data in this accession were collected from ship WALKER between July 1, 1991 to July 10, 1991. The real time data of water temperature at varying depth...

  19. Prof. John Wood, Chief Executive Designate, Dr Gordon Walker, Directorate, Chief Executive, Prof. Ken J. Peach, Head of the Particle Physics Department, CLRC Rutherford Appleton Laboratory, United Kingdom

    CERN Multimedia

    Patrice Loïez

    2001-01-01

    L. to. r.: Dr. Ian Wilson, CLIC Deputy Study Leader, Prof. Ken J. Peach, Head of the Particle Physics Department, Prof. John Wood, Chief Executive Designate, Dr. Gordon Walker, Directorate, Chief Executive

  20. 500 kyr of Indian Ocean Walker Circulation Variability Using Foraminiferal Mg/Ca and Stable Isotopes

    Science.gov (United States)

    Groeneveld, J.; Mohtadi, M.; Lückge, A.; Pätzold, J.

    2017-12-01

    The tropical Indian Ocean is a key location for paleoclimate research affected by different oceanographic and atmospheric processes. Annual climate variations are strongly controlled by the Indian and Asian Monsoon characterized by bi-annually reversing trade winds. Inter-annual climate variations in the Walker circulation are caused by the Indian Ocean Dipole and El Niño-Southern Oscillation resulting in either heavy flooding or severe droughts like for example the famine of 2011 in eastern Africa. Oceanographically the tropical western Indian Ocean receives water masses from the Indonesian Gateway area, sub-Antarctic waters that upwell south of the equator, and the outflow waters from the highly saline Red Sea. On the other hand, the tropical western Indian Ocean is a major source for providing water masses to the Agulhas Current system. Although the eastern Indian Ocean has been studied extensively, the tropical western Indian Ocean is still lacking in high quality climate-archives that have the potential to provide important information to understand how the ocean and atmospheric zonal circulation have changed in the past, and possibly will change in the future. Until now there were no long sediment cores available covering several glacial-interglacial cycles in the tropical western Indian Ocean. Core GeoB 12613-1, recovered during RV Meteor Cruise M75/2 east of the island of Pemba off Tanzania, provides an open-ocean core with well-preserved sediments covering the last five glacial-interglacial cycles ( 500 kyr). Mg/Ca and stable isotopes on both surface- and thermocline dwelling foraminifera have been performed to test how changes in sea water temperatures and relative sea water salinity were coupled on orbital time scales. The results are compared with similar records generated for the tropical eastern Indian Ocean in core SO139-74KL off Sumatra. Water column stratification on both sides of the Indian Ocean and the cross-basin gradients in sea water

  1. Henri Cartier-Bresson / Walker Evans : Photographier l’Amérique (1929-1947

    Directory of Open Access Journals (Sweden)

    François Brunet

    2009-08-01

    Full Text Available Dans un mot adressé en 2001 à Peter Galassi, conservateur de la photographie au MOMA, Henri Cartier-Bresson, alors âgé de quatre-vingt-treize ans, écrivait plaisamment — mais non pas complaisamment : « If it had not been for the challenge of the work of Walker Evans, I don’t think I would have remained a fotographer » (« sans le défi constitué par le travail de Walker Evans, je ne crois pas que je serais resté fotographe ». Pour fêter le centenaire de Cartier-Bresson, c’est ce défi — plutôt ...

  2. Biological aspects of Periga circumstans Walker, 1855 (Lepidoptera: Saturniidae: Hemileucinae with larvae reared on khaki and mate-plant leaves

    Directory of Open Access Journals (Sweden)

    A. Specht

    Full Text Available The goal of the present study was to investigate biological aspects of Periga circumstans Walker, 1855 (Lepidoptera: Saturniidae: Hemileucinae whose larvae were fed on leaves of khaki-plant (Diospyros khaki Linnaeus - Ebenaceae and Mate-plant (Ilex paraguariensis Saint Hilaire - Aquifoliaceae leaves. The biological parameters were obtained from specimens kept under controlled conditions: temperature of 25 ± 1 °C, relative humidity of 70 ± 10%, and photoperiod of 12 hours. For each developmental stage, morphological and ethological parameters are described. The larvae passed through six instars with a growth average rate of 1.4 for each instar. The host plants influenced significantly only the total duration of the larval phase, which was prolonged for larvae fed on khaki-plant leaves. Several aspects related to the morphology and the ethology of P. circumstans are similar to those described for Lonomia obliqua Walker, 1855.

  3. Comparative study of two female African-American Writers in 20 Centu-ry-Alice Walker VS. Toni Morriso

    Institute of Scientific and Technical Information of China (English)

    桂生义

    2013-01-01

    Toni Morrison and Alice Walker are among the most outstanding female African-American writers in Contemporary American Literature. Their works have been popular since 1960s to now. Although Walker and Morrison grew up under differ⁃ent family environments, they had the same experience of witnessing African-American women’s movements in last Century;therefore, they reached an agreement on writing thoughts and contents. For instance, they both referred to Racism, Sexism and“Womanism”in many of their works. This dissertation studies about the two authors’difference and sameness descriptions on Af⁃rican-American women’s identities, social status, rights, powers and fates,and to express their self-consciousness and bright prospection after experiencing the most painful encounters through comparative study on two of their short stories—Everyday Use and Recitatif.

  4. Notes on Apidae and Vespidae (Hymenoptera) Species Collected by Bait Traps in OrganicVineyard and Orchards of Kemalpaşa (İzmir), Western Turkey

    OpenAIRE

    ÜZÜM, Ahu; TANYERİ, Rukiye; GÜLPERÇİN, Nilay; TEZCAN, Serdar; YILDIRIM, Erol

    2010-01-01

    Hymenoptera species collected by bait traps during the months of June-October in organic vineyard and orchards in Kemalpaşa district, (İzmir) of Western Turkey were evaluated in this study. As a result, six species belonging 2007 to two families of Hymenoptera were determined. Those were Apis mellifera Linnaeus, 1758, Vespula germanica (Fabricius, 1793), Vespa crabro Linnaeus, 1758, Vespa orientalis Linnaeus, 1771, Polistes dominulus (Christ, 1791) and Polistes gallicus (Linnaeus, 1767). Amon...

  5. Improved sensitivity to venom specific-immunoglobulin E by spiking with the allergen component in Japanese patients suspected of Hymenoptera venom allergy

    Directory of Open Access Journals (Sweden)

    Naruo Yoshida

    2015-07-01

    Conclusions: The measurement of sIgE following spiking of rVes v 5 and rPol d 5 by conventional testing in Japanese subjects with sIgE against hornet and paper wasp venom, respectively, improved the sensitivity for detecting Hymenoptera venom allergy. Improvement testing for measuring sIgE levels against hornet and paper wasp venom has potential for serologically elucidating Hymenoptera allergy in Japan.

  6. A new species of genus Chorebus Haliday (Hymenoptera, Alysiinae parasitising Hexomyza caraganae Gu (Diptera, Agromyzidae from NW China

    Directory of Open Access Journals (Sweden)

    Tao Li

    2017-03-01

    Full Text Available Chorebus (Stiphrocera hexomyzae sp. n. (Hymenoptera, Braconidae, Alysiinae, Dacnusini is described and illustrated. It was reared from twig galls of Hexomyza caraganae Gu (Diptera, Agromyzidae on Caragana korshinskii Kom. f. (Fabaceae in Ningxia and Inner Mongolia (NW China. A partial key to related or similar Chorebus species is provided.

  7. Preliminary taxonomic study of the genus Praon (Hymenoptera:Braconidae:Aphidiinae) and its host associations in Iran

    Czech Academy of Sciences Publication Activity Database

    Rakhshani, E.; Talebi, A. A.; Manzari, S.; Tomanovic, Ž.; Starý, Petr; Rezwani, A.

    2007-01-01

    Roč. 26, č. 2 (2007), s. 19-34 ISSN 0259-9996 R&D Projects: GA AV ČR IBS5007102 Institutional research plan: CEZ:AV0Z50070508 Keywords : genus Praon * Hymenoptera * Iran Subject RIV: EH - Ecology, Behaviour

  8. Temperature dependent functional response of Diaeretiella rapae (Hymenoptera: Aphidiidae) to the cabbage aphid, Brevicoryne brassicae (Hemiptera: Aphididae)

    DEFF Research Database (Denmark)

    Moayeri, Hamid R. S.; Madadi, Hossein; Pouraskari, Hossein

    2013-01-01

    Diaeretiella rapae MacIntosh (Hymenoptera: Aphidiidae) is one of the most common and successful parasitoids of the cabbage aphid. The functional response of D. rapae towards cabbage aphids was examined in laboratory studies at three constant temperatures, 17°C, 25°C and 30°C. D. rapae exhibited a...

  9. Biological parameters and thermal requirements of the parasitoid Praon volucre (Hymenoptera: Braconidae) with Macrosiphum euphorbiae (Hemiptera: Aphididae) as host

    NARCIS (Netherlands)

    Conti, De B.F.; Bueno, V.H.P.; Sampaio, M.V.; Lenteren, van J.C.

    2011-01-01

    The effect of temperature on the biology of Praon volucre (Haliday, 1833) (Hymenoptera: Braconidae) in Macrosiphum euphorbiae (Thomas, 1878) (Hemiptera: Aphididae) hosts was studied and the thermal requirements of the parasitoid were determined. Experiments were carried out at 16, 19, 22, 25, and 28

  10. A new species of Tamarixia Mercet (Hymenoptera, Eulophidae, parasitoid of Trioza aguacate Hollis & Martin (Hemiptera, Triozidae in Mexico

    Directory of Open Access Journals (Sweden)

    Zoya Yefremova

    2014-01-01

    Full Text Available Tamarixia aguacatensis Yefremova, sp. n. (Hymenoptera: Eulophidae: Tetrastichinae is described from Mexico as a parasitoid of the avocado psyllid, Trioza aguacate Hollis & Martin (Hemiptera: Triozidae. Trioza aguacate is a serious pest of avocado, Persea americana Miller. A key to the species of Tamarixia Mercet in Mexico is given.

  11. Record of the genus Arrhenophagoidea Girault (Hymenoptera: Chalcidoidea: Encyrtidae from India, description of a new species from the Andaman Islands

    Directory of Open Access Journals (Sweden)

    M. Hayat

    2014-05-01

    Full Text Available The genus Arrhenophagoidea Girault (Hymenoptera: Encyrtidae is recorded for the first time from India and the Oriental region, and a new species, A. andamanica sp. Nov. is described from material collected in the Andaman and Nicobar Islands, India. As the genus is newly recorded from the Oriental region, a brief diagnosis is also given.

  12. A new species of the Camponotus aureopilus VIEHMEYER, 1914 species-group (Hymenoptera: Formicidae) from Papua New Guinea

    Czech Academy of Sciences Publication Activity Database

    Shattuck, S.; Janda, Milan

    2009-01-01

    Roč. 12, - (2009), s. 251-253 ISSN 1994-4136 R&D Projects: GA MŠk LC06073; GA AV ČR KJB612230701 Grant - others:U.S. National Science Foundation(US) DEB-02-11591 Institutional research plan: CEZ:AV0Z50070508 Keywords : taxonomic description * Hymenoptera * Formicidae Subject RIV: EG - Zoology

  13. A new species of Megischus Brullé (Hymenoptera, Stephanidae from China, with a key to the Chinese species

    Directory of Open Access Journals (Sweden)

    Hong Chun-dan

    2010-11-01

    Full Text Available A new species of Megischus Brullé from China, M. aplicatus sp. n., is described and illustrated. A key to the Chinese species of Megischus is added. The holotype is deposited in the Parasitic Hymenoptera Collection of Zhejiang University, Hangzhou.

  14. Two new species of Oobius (Hymenoptera: Encyrtidae) and their phylogenetic relationship with other congeners from northeastern Asia

    Science.gov (United States)

    Yan-Xia Yao; Jian J. Duan; Jason L. Mottern; Xiao-Yi Wang; Zhong-Qi Yang; Leah S. Bauer; Michael W. Gates

    2018-01-01

    Two new species of egg parasitoids, Oobius saimaensis Yao and Mottern new species and Oobius fleischeri Yao and Duan new species (Hymenoptera: Encyrtidae), are described from eggs of Agrilus fleischeri Obenberger, 1925 (Coleoptera: Buprestidae). Agrilus fleischeri is a phloemfeeding woodborer of poplar (...

  15. The parasites of cereal stem borers (Lepidoptera: Cossidae, Crambidae, Noctuidae, Pyralidae) in Africa, belonging to the family Braconidae (Hymenoptera: Ichneumonoidea)

    NARCIS (Netherlands)

    Achterberg, van C.; Polaszek, A.

    1996-01-01

    A review is given of the parasites (parasitoids) of the African cereal stem borers (including introduced species) belonging to the family Braconidae (Hymenoptera); 38 species belonging to 19 genera are keyed and treated. Three new species are described: Macrocentrus sesamivorus spec. nov. from

  16. New species of Megastylus (Hymenoptera: Ichneumonidae: Orthocentrinae) reared from larvae of Keroplatidae fungus gnats (Diptera) in a Dutch orchid greenhouse

    NARCIS (Netherlands)

    Humala, Andrei E.; Kruidhof, Marjolein; Woelke, Joop

    2017-01-01

    A new parasitoid wasp species belonging to the genus Megastylus (Hymenoptera: Ichneumonidae: Orthocentrinae) found in an orchid nursery in The Netherlands is described and illustrated: Megastylus woelkei sp. nov. It was reared from parasitized larvae of fungus gnats (Diptera: Keroplatidae). The

  17. Effect of electromagnetic fields on the creation of scalar particles in a flat Robertson-Walker space-time

    International Nuclear Information System (INIS)

    Haouat, S.; Chekireb, R.

    2012-01-01

    The influence of electromagnetic fields on the creation of scalar particles from vacuum in a flat Robertson-Walker space-time is studied. The Klein-Gordon equation with varying electric field and constant magnetic one is solved. The Bogoliubov transformation method is applied to calculate the pair creation probability and the number density of created particles. It is shown that the electric field amplifies the creation of scalar particles while the magnetic field minimizes it. (orig.)

  18. Low carbohydrate, high fat diet impairs exercise economy and negates the performance benefit from intensified training in elite race walkers

    Science.gov (United States)

    Ross, Megan L.; Garvican‐Lewis, Laura A.; Welvaert, Marijke; Heikura, Ida A.; Forbes, Sara G.; Mirtschin, Joanne G.; Cato, Louise E.; Strobel, Nicki; Sharma, Avish P.; Hawley, John A.

    2017-01-01

    Key points Three weeks of intensified training and mild energy deficit in elite race walkers increases peak aerobic capacity independent of dietary support.Adaptation to a ketogenic low carbohydrate, high fat (LCHF) diet markedly increases rates of whole‐body fat oxidation during exercise in race walkers over a range of exercise intensities.The increased rates of fat oxidation result in reduced economy (increased oxygen demand for a given speed) at velocities that translate to real‐life race performance in elite race walkers.In contrast to training with diets providing chronic or periodised high carbohydrate availability, adaptation to an LCHF diet impairs performance in elite endurance athletes despite a significant improvement in peak aerobic capacity. Abstract We investigated the effects of adaptation to a ketogenic low carbohydrate (CHO), high fat diet (LCHF) during 3 weeks of intensified training on metabolism and performance of world‐class endurance athletes. We controlled three isoenergetic diets in elite race walkers: high CHO availability (g kg−1 day−1: 8.6 CHO, 2.1 protein, 1.2 fat) consumed before, during and after training (HCHO, n = 9); identical macronutrient intake, periodised within or between days to alternate between low and high CHO availability (PCHO, n = 10); LCHF (diets providing chronic or periodised high‐CHO availability, and despite a significant improvement in V˙O2 peak , adaptation to the topical LCHF diet negated performance benefits in elite endurance athletes, in part due to reduced exercise economy. PMID:28012184

  19. Characterization of the damage of Spodoptera eridania (Cramer) and Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) to structures of cotton plants

    OpenAIRE

    Santos, Karen B dos; Meneguim, Ana M; Santos, Walter J dos; Neves, Pedro M O J; Santos, Rachel B dos

    2010-01-01

    The cotton plant, Gossypium hirsutum, hosts various pests that damage different structures. Among these pests, Spodoptera cosmioides (Walker) and Spodoptera eridania (Cramer) (Lepidoptera: Noctuidae) are considered important. The objectives of this study were to characterize and to quantify the potential damage of S. eridania and S. cosmioides feeding on different structures of cotton plants. For this purpose, newly-hatched larvae were reared on the following plant parts: leaf and flower bud;...

  20. Global bifurcation of solutions of the mean curvature spacelike equation in certain Friedmann-Lemaître-Robertson-Walker spacetimes

    Science.gov (United States)

    Dai, Guowei; Romero, Alfonso; Torres, Pedro J.

    2018-06-01

    We study the existence of spacelike graphs for the prescribed mean curvature equation in the Friedmann-Lemaître-Robertson-Walker (FLRW) spacetime. By using a conformal change of variable, this problem is translated into an equivalent problem in the Lorentz-Minkowski spacetime. Then, by using Rabinowitz's global bifurcation method, we obtain the existence and multiplicity of positive solutions for this equation with 0-Dirichlet boundary condition on a ball. Moreover, the global structure of the positive solution set is studied.