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Sample records for beetles facilitate aggregation

  1. Striped Cucumber Beetle (Coleoptera: Chrysomelidae) Aggregation in Response to Cultivar and Flowering.

    Science.gov (United States)

    Gardner, Jeffrey; Hoffmann, Michael P; Mazourek, Michael

    2015-04-01

    The striped cucumber beetle [Acalymma vittatum (F.)] is a specialist pest of cucurbits throughout its range in the United States and Canada. Improved integrated pest management options are needed across the pest's range, especially on organic farms where there are few effective controls. Trap cropping in cucurbits is an option, but there are significant challenges to the technique. Because cucurbit flowers are highly attractive to the beetles, four field experiments tested whether cultivar and phenology interact to preferentially aggregate beetles. The first experiment tested the hypothesis that cucurbit flowers were more attractive to striped cucumber beetles than was foliage. The second experiment tested whether there were differences in beetle aggregation between two relatively attractive cultivars. The third and fourth experiments were factorial designs with two plant cultivars and two levels of flowering to specifically test for an interaction of cultivar and flowering. Results indicated that flowers were more attractive than foliage, beetle aggregation was affected by plant cultivar, and that there was an interaction of cultivar with flowering. We conclude that a single cultivar may be sufficient to serve as a generic trap crop to protect a wide variety of cucurbits. PMID:26313184

  2. Multitrophic interaction facilitates parasite-host relationship between an invasive beetle and the honey bee.

    Science.gov (United States)

    Torto, Baldwyn; Boucias, Drion G; Arbogast, Richard T; Tumlinson, James H; Teal, Peter E A

    2007-05-15

    Colony defense by honey bees, Apis mellifera, is associated with stinging and mass attack, fueled by the release of alarm pheromones. Thus, alarm pheromones are critically important to survival of honey bee colonies. Here we report that in the parasitic relationship between the European honey bee and the small hive beetle, Aethina tumida, the honey bee's alarm pheromones serve a negative function because they are potent attractants for the beetle. Furthermore, we discovered that the beetles from both Africa and the United States vector a strain of Kodamaea ohmeri yeast, which produces these same honey bee alarm pheromones when grown on pollen in hives. The beetle is not a pest of African honey bees because African bees have evolved effective methods to mitigate beetle infestation. However, European honey bees, faced with disease and pest management stresses different from those experienced by African bees, are unable to effectively inhibit beetle infestation. Therefore, the environment of the European honey bee colony provides optimal conditions to promote the unique bee-beetle-yeast-pollen multitrophic interaction that facilitates effective infestation of hives at the expense of the European honey bee. PMID:17483478

  3. Age and aggregation trigger mating behaviour in the small hive beetle, Aethina tumida (Nitidulidae)

    Science.gov (United States)

    Mustafa, Sandra G.; Spooner-Hart, Robert; Duncan, Michael; Pettis, Jeffery S.; Steidle, Johannes L. M.; Rosenkranz, Peter

    2015-10-01

    This study aimed to investigate the poorly documented reproductive behaviour of the small hive beetle, Aethina tumida (Nitidulidae), a honey bee ( Apis mellifera) parasite. We described the mating behaviour in detail and tested the hypothesis that beetle aggregation plays a vital role in mating in this species. Gender preference was examined in the context of age-dependency and possible chemical communication. Beetles started mating at a high frequency 18 days after emergence from the soil but only if they were aggregated ( p sex ( p sex ( p < 0.01). This suggests that chemical substances produced by the beetles themselves play a role in mating. Mating behaviour was characterised by a short pre-copulation courtship and female aggression towards other females and copulating couples. Both behaviours may be indicative of cryptic female choice. Delayed onset of reproductive behaviour is typical of many polygamous species, whilst the indispensability of aggregation for onset of sexual behaviour seems to be a feature unique to A. tumida. Both strategies support mass reproduction in this parasitic species, enabling A. tumida to overcome its honey bee host colony, and are probably triggered by chemotactic cues.

  4. Host-Tree Monoterpenes and Biosynthesis of Aggregation Pheromones in the Bark Beetle Ips paraconfusus

    Directory of Open Access Journals (Sweden)

    John A. Byers

    2012-01-01

    Full Text Available A paradigm developed in the 1970s that Ips bark beetles biosynthesize their aggregation pheromone components ipsenol and ipsdienol by hydroxylating myrcene, a host tree monoterpene. Similarly, host α-pinene was hydroxylated to a third pheromone component cis-verbenol. In 1990, however, we reported that amounts of ipsenol and ipsdienol produced by male Ips paraconfusus (Coleoptera: Scolytinae feeding in five host pine species were nearly the same, even though no detectable myrcene precursor was detected in one of these pines (Pinus sabiniana. Subsequent research showed ipsenol and ipsdienol are also biosynthesized from smaller precursors such as acetate and mevalonate, and this de novo pathway is the major one, while host tree myrcene conversion by the beetle is the minor one. We report concentrations of myrcene, α-pinene and other major monoterpenes in five pine hosts (Pinus ponderosa, P. lambertiana, P. jeffreyi, P. sabiniana, and P. contorta of I. paraconfusus. A scheme for biosynthesis of ipsdienol and ipsenol from myrcene and possible metabolites such as ipsenone is presented. Mass spectra and quantities of ipsenone are reported and its possible role in biosynthesis of aggregation pheromone. Coevolution of bark beetles and host trees is discussed in relation to pheromone biosynthesis, host plant selection/suitability, and plant resistance.

  5. Stiffness gradient of the beetle penis facilitates propulsion in the spiraled female spermathecal duct.

    Science.gov (United States)

    Filippov, Alexander E; Matsumura, Yoko; Kovalev, Alexander E; Gorb, Stanislav N

    2016-01-01

    It is well known that sexual selection is the main driving force of substantial diversity of genitalia found in animals. However, how it facilitates the diversity is still largely unknown, because genital morpho/physical features and motions/functional morphology of the structures in sexual intercourse are not linked for the vast majority of organisms. Here we showed the presence of material gradient and numerically studied an effect of stiffness gradient of the beetle penis during its propulsion through the female duct. We found that stiffness gradient on the penis essentially affects its propulsion. Microscopic investigation suggests the possibility that the tip of the hyper-elongated penis is softer than the rest of it, and our numerical model confirms that this type of distribution of stiffness gradient aids in faster propulsion than other types. This result indicates that previously ignored physical properties of genital materials are of crucial importance in evolutionary studies of genitalia. PMID:27334674

  6. Multitrophic interaction facilitates parasite–host relationship between an invasive beetle and the honey bee

    OpenAIRE

    Torto, Baldwyn; Boucias, Drion G.; Arbogast, Richard T.; Tumlinson, James H.; Teal, Peter E. A.

    2007-01-01

    Colony defense by honey bees, Apis mellifera, is associated with stinging and mass attack, fueled by the release of alarm pheromones. Thus, alarm pheromones are critically important to survival of honey bee colonies. Here we report that in the parasitic relationship between the European honey bee and the small hive beetle, Aethina tumida, the honey bee's alarm pheromones serve a negative function because they are potent attractants for the beetle. Furthermore, we discovered that the beetles f...

  7. Bark Beetles, Pityogenes bidentatus, Orienting to Aggregation Pheromone Avoid Conifer Monoterpene Odors When Flying but Not When Walking

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    John A. Byers

    2012-01-01

    Full Text Available Previous studies and data presented here suggest that odors from healthy host Scotch pine (Pinus sylvestris and nonhost Norway spruce (Picea abies, as well as major monoterpenes of these trees at natural release rates, significantly reduce the attraction of flying bark beetles, Pityogenes bidentatus, of both sexes to their aggregation pheromone components grandisol and cis-verbenol in the field, as tested by slow rotation of trap pairs. In contrast, P. bidentatus males and females walking in an open-arena olfactometer in the laboratory did not avoid monoterpene vapors at release rates spanning several orders of magnitude in combination with aggregation pheromone. The bark beetle may avoid monoterpenes when flying as a mechanism for avoiding nonhost species, vigorous and thus unsuitable host trees, as well as harmful resinous areas of hosts. Inhibition of this flight avoidance response in beetles after landing would allow them to initiate, or to find and enter, gallery holes with high monoterpene vapor concentrations in order to feed and reproduce.

  8. Field responses of the Asian larch bark beetle, Ips subelongatus, to potential aggregation pheromone components: disparity between two populations in northeastern China

    Institute of Scientific and Technical Information of China (English)

    Li-Wen Song; Qing-He Zhang; Yue-Qu Chen; Tong-Tong Zuo; Bing-Zhong Ren

    2011-01-01

    Behavioral responses of the Asian larch bark beetle, Ips subelongatus Motsch. to three potential aggregation pheromone components, ipsenol (racemic or [-]-enantiomer), ipsdienol (racemic or [+]-enantiomer) and 3-methyl-3-buten-1 -ol, were tested using partial or full factorial experimental designs in two provinces (Inner Mongolia and Jilin) of northeastern China. Our field bioassays in Inner Mongolia (Larix principis- rupprechtii Mayr. plantation) clearly showed that ipsenol, either racemic or 97%-(-)-enantiomer, was the only compound that significantly attracted both sexes of I. subelongatus, while all other compounds (singly or in combinations) were unattractive. There were no two- or three-way synergistic interactions. However, in Jilin Province (L. gmelini [Rupr.] Rupr. Plantation), all the individual compounds tested were inactive, except a very weak activity by 97%-(-)-ipsenol in 2004 when the beetle population was very high. While a combination of ipsenol and ipsdienol (racemates or enantiomerically pure natural enantiomers) showed a significant attraction for both sexes of I. subelongatus, indicating a two-way synergistic interaction between these two major components, addition of 3-methyl-3-buten-l-ol to these active binary blend(s) did not have any effects on trap catches, suggesting that ipsenol and ipsdienol are the synergistic aggregation pheromone components of I. subelongatus in Jilin Province. It seems that 97%-(-)-ipsenol in Inner Mongolia or the binary blend of 97%-(-)-ipsenol and 97%-(+)-ipsdienol in Jilin Province are superior to their corresponding racemates, which might be due either to weak inhibitory effects of the antipode enantiomers or to reduced release rates of the active natural enantiomers) in the racemate(s). Our current bioassay results suggest that there is a strong geographical variation in aggregation pheromone response of I. subelongatus in northeastern China. Future research on the pheromone production and response of I

  9. Asparagus Beetle and Spotted Asparagus Beetle

    OpenAIRE

    Erin W Hodgson; Drost, Dan

    2007-01-01

    Asparagus beetle, Crioceris asparagi, and spotted asparagus beetle, C. duodecimpunctata are leaf beetles in the family Chrysomelidae. These beetles feed exclusively on asparagus and are native to Europe. Asparagus beetle is the more economically injurious of the two species.

  10. How far away is the next basket of eggs? Spatial memory and perceived cues shape aggregation patterns in a leaf beetle.

    Science.gov (United States)

    Stephan, Jörg G; Stenberg, Johan A; Björkman, Christer

    2015-04-01

    Gregarious organisms need to handle the trade-off between increasing food competition and the positive effects of group living, and this is particularly important for ovipositing females. We hypothesized that insect females consider how many conspecifics previously visited a host plant. In a no-choice assay, we show that the gregarious blue willow leaf beetle (Phratora vulgatissima) laid the most eggs and the largest clutches on plants where a sequence of few individual females was released, compared to plants where one or many different females were repeatedly released. Therefore, this species is more sensitive to the indirectly perceived number of conspecifics than the directly perceived number of eggs on a plant. We further hypothesized that females adjust their own intra-plant egg clutch distribution to that of conspecifics and discovered a new behavioral component, i.e., the modulation of distances between clutches. Females adjusted these distances in ways indicating the use of spatial memory, because the largest distance increases were observed on plants with their own clutches, compared to plants with clutches from conspecifics. However, adjustment of aggregation level and distance between clutches occurred only on a suitable, and not on an unsuitable, Salix genotype. We conclude that both behaviors should reduce competition between sibling and non-sibling larvae. PMID:26230012

  11. What is Next in Bark Beetle Phylogeography?

    Directory of Open Access Journals (Sweden)

    Dimitrios N. Avtzis

    2012-05-01

    Full Text Available Bark beetle species within the scolytid genera Dendroctonus, Ips, Pityogenes and Tomicus are known to cause extensive ecological and economical damage in spruce and pine forests during epidemic outbreaks all around the world. Dendroctonus ponderosae poses the most recent example having destroyed almost 100,000 km2 of conifer forests in North America. The success and effectiveness of scolytid species lies mostly in strategies developed over the course of time. Among these, a complex system of semiochemicals promotes the communication and aggregation on the spot of infestation facilitating an en masse attack against a host tree’s defenses; or an association with fungi that evolved either in the form of nutrition (ambrosia fungi or even by reducing the resistance of host trees (blue-stain fungi. Although often specific to a tree genus or species, some bark beetles are polyphagous and have the ability to switch on to new hosts and extend their host range (i.e., between conifer genera such as Pityogenes chalcographus or even from conifer to deciduous trees as Polygraphus grandiclava. A combination of these capabilities in concert with life history or ecological traits explains why bark beetles are considered interesting subjects in evolutionary studies. Several bark beetle species appear in phylogeographic investigations, in an effort to improve our understanding of their ecology, epidemiology and evolution. In this paper investigations that unveil the phylogeographic history of bark beetles are reviewed. A close association between refugial areas and postglacial migration routes that insects and host trees have followed in the last 15,000 BP has been suggested in many studies. Finally, a future perspective of how next generation sequencing will influence the resolution of phylogeographic patterns in the coming years is presented. Utilization of such novel

  12. Pheromone production in bark beetles.

    Science.gov (United States)

    Blomquist, Gary J; Figueroa-Teran, Rubi; Aw, Mory; Song, Minmin; Gorzalski, Andrew; Abbott, Nicole L; Chang, Eric; Tittiger, Claus

    2010-10-01

    The first aggregation pheromone components from bark beetles were identified in 1966 as a mixture of ipsdienol, ipsenol and verbenol. Since then, a number of additional components have been identified as both aggregation and anti-aggregation pheromones, with many of them being monoterpenoids or derived from monoterpenoids. The structural similarity between the major pheromone components of bark beetles and the monoterpenes found in the host trees, along with the association of monoterpenoid production with plant tissue, led to the paradigm that most if not all bark beetle pheromone components were derived from host tree precursors, often with a simple hydroxylation producing the pheromone. In the 1990 s there was a paradigm shift as evidence for de novo biosynthesis of pheromone components began to accumulate, and it is now recognized that most bark beetle monoterpenoid aggregation pheromone components are biosynthesized de novo. The bark beetle aggregation pheromones are released from the frass, which is consistent with the isoprenoid aggregation pheromones, including ipsdienol, ipsenol and frontalin, being produced in midgut tissue. It appears that exo-brevocomin is produced de novo in fat body tissue, and that verbenol, verbenone and verbenene are produced from dietary α-pinene in fat body tissue. Combined biochemical, molecular and functional genomics studies in Ips pini yielded the discovery and characterization of the enzymes that convert mevalonate pathway intermediates to pheromone components, including a novel bifunctional geranyl diphosphate synthase/myrcene synthase, a cytochrome P450 that hydroxylates myrcene to ipsdienol, and an oxidoreductase that interconverts ipsdienol and ipsdienone to achieve the appropriate stereochemistry of ipsdienol for pheromonal activity. Furthermore, the regulation of these genes and their corresponding enzymes proved complex and diverse in different species. Mevalonate pathway genes in pheromone producing male I. pini

  13. Charles Darwin, beetles and phylogenetics

    Science.gov (United States)

    Beutel, Rolf G.; Friedrich, Frank; Leschen, Richard A. B.

    2009-11-01

    Here, we review Charles Darwin’s relation to beetles and developments in coleopteran systematics in the last two centuries. Darwin was an enthusiastic beetle collector. He used beetles to illustrate different evolutionary phenomena in his major works, and astonishingly, an entire sub-chapter is dedicated to beetles in “The Descent of Man”. During his voyage on the Beagle, Darwin was impressed by the high diversity of beetles in the tropics, and he remarked that, to his surprise, the majority of species were small and inconspicuous. However, despite his obvious interest in the group, he did not get involved in beetle taxonomy, and his theoretical work had little immediate impact on beetle classification. The development of taxonomy and classification in the late nineteenth and earlier twentieth century was mainly characterised by the exploration of new character systems (e.g. larval features and wing venation). In the mid-twentieth century, Hennig’s new methodology to group lineages by derived characters revolutionised systematics of Coleoptera and other organisms. As envisioned by Darwin and Ernst Haeckel, the new Hennigian approach enabled systematists to establish classifications truly reflecting evolution. Roy A. Crowson and Howard E. Hinton, who both made tremendous contributions to coleopterology, had an ambivalent attitude towards the Hennigian ideas. The Mickoleit school combined detailed anatomical work with a classical Hennigian character evaluation, with stepwise tree building, comparatively few characters and a priori polarity assessment without explicit use of the outgroup comparison method. The rise of cladistic methods in the 1970s had a strong impact on beetle systematics. Cladistic computer programs facilitated parsimony analyses of large data matrices, mostly morphological characters not requiring detailed anatomical investigations. Molecular studies on beetle phylogeny started in the 1990s with modest taxon sampling and limited DNA data

  14. Structure of Phoretic Mite Assemblages Across Subcortical Beetle Species at a Regional Scale.

    Science.gov (United States)

    Pfammatter, Jesse A; Coyle, David R; Gandhi, Kamal J K; Hernandez, Natalie; Hofstetter, Richard W; Moser, John C; Raffa, Kenneth F

    2016-02-01

    Mites associated with subcortical beetles feed and reproduce within habitats transformed by tree-killing herbivores. Mites lack the ability to independently disperse among these habitats, and thus have evolved characteristics that facilitate using insects as transport between resources. Studies on associations between mites and beetles have historically been beetle-centric, where an assemblage of mite species is characterized on a single beetle species. However, available evidence suggests there may be substantial overlap among mite species on various species of beetles utilizing similar host trees. We assessed the mite communities of multiple beetle species attracted to baited funnel traps in Pinus stands in southern Wisconsin, northern Arizona, and northern Georgia to better characterize mite dispersal and the formation of mite-beetle phoretic associations at multiple scales. We identified approximately 21 mite species totaling 10,575 individuals on 36 beetle species totaling 983 beetles. Of the mites collected, 97% were represented by eight species. Many species of mites were common across beetle species, likely owing to these beetles' common association with trees in the genus Pinus. Most mite species were found on at least three beetle species. Histiostoma spp., Iponemus confusus Lindquist, Histiogaster arborsignis Woodring and Trichouropoda australis Hirschmann were each found on at least seven species of beetles. While beetles had largely similar mite membership, the abundances of individual mite species were highly variable among beetle species within each sampling region. Phoretic mite communities also varied within beetle species between regions, notably for Ips pini (Say) and Ips grandicollis (Eichhoff). PMID:26496952

  15. A computer-assisted 3D model for analyzing the aggregation of tumorigenic cells reveals specialized behaviors and unique cell types that facilitate aggregate coalescence.

    Directory of Open Access Journals (Sweden)

    Amanda Scherer

    Full Text Available We have developed a 4D computer-assisted reconstruction and motion analysis system, J3D-DIAS 4.1, and applied it to the reconstruction and motion analysis of tumorigenic cells in a 3D matrix. The system is unique in that it is fast, high-resolution, acquires optical sections using DIC microscopy (hence there is no associated photoxicity, and is capable of long-term 4D reconstruction. Specifically, a z-series at 5 μm increments can be acquired in less than a minute on tissue samples embedded in a 1.5 mm thick 3D Matrigel matrix. Reconstruction can be repeated at intervals as short as every minute and continued for 30 days or longer. Images are converted to mathematical representations from which quantitative parameters can be derived. Application of this system to cancer cells from established lines and fresh tumor tissue has revealed unique behaviors and cell types not present in non-tumorigenic lines. We report here that cells from tumorigenic lines and tumors undergo rapid coalescence in 3D, mediated by specific cell types that we have named "facilitators" and "probes." A third cell type, the "dervish", is capable of rapid movement through the gel and does not adhere to it. These cell types have never before been described. Our data suggest that tumorigenesis in vitro is a developmental process involving coalescence facilitated by specialized cells that culminates in large hollow spheres with complex architecture. The unique effects of select monoclonal antibodies on these processes demonstrate the usefulness of the model for analyzing the mechanisms of anti-cancer drugs.

  16. Chiral and Nonchiral GCxGC/TOFMS Analysis of Natural Compounds: The Case of Possible Aggregation Pheromones of Chinese Bark Beetles lps shangrila and lps nitidus

    Czech Academy of Sciences Publication Activity Database

    Hoskovec, Michal; Kalinová, Blanka; Knížek, M.

    Rijeka: InTech, 2012 - (Salih, B.; Celikbicak, O.), s. 325-346 ISBN 978-953-51-0127-7 R&D Projects: GA MŠk ME 860 Institutional research plan: CEZ:AV0Z40550506 Keywords : China * pheromones * Ips shangrila * Ips nitidus Subject RIV: CC - Organic Chemistry http://www.intechopen.com/books/gas-chromatography-in-plant-science- wine -technology-toxicology-and-some-specific-applications/chiral-and-nonchiral-gc-gc-tofms-analysis-of-natural-compounds-the-case-of-possible-aggregation-pher

  17. Present and future use of semiochemicals in pest management of bark beetles.

    Science.gov (United States)

    Vité, J P; Baader, E

    1990-11-01

    Attractive compounds affecting the mass aggregation of bark beetle populations on host trees suitable for colonization usually consist of two obligatory components that act synergistically and species-specifically. Semiochemicals inhibiting response act on their own and seem less specific. From nearly 100 species investigated so far, mass aggregation can be simulated with commercial synthetics in about nine species of economic importance. Aspects leading to the application of attractants in monitoring and mass trapping pest populations affecting European spruce forests result from intensive coordinated research at the university, industry, and forestry level. Technology transfer was facilitated by, and adapted to, the infrastructure of European forestry; traps economically replace the trap tree methods conventionally used for centuries. Expected applications in the near future are refined monitoring methods to measure population levels and predict damages. Also, mass trapping should remain a worthwhile tool in preventing beetle damage in forests under management intensive enough to remove excessive breeding material. In the long run, response-inhibiting semiochemicals resulting in the dispersal of pest populations (Ablenkstoffe) may gain wider application. The spruce engraverIps typographus L. and its associatePityogenes chalcographus L. are used as examples to describe the feasibility of developing and applying inhibitors as new tools in the management of bark beetle pests: Applying a slow-release verbenone formulation (verbenone strip) wrapped around the trunk of spruce trees at breast height appears to protect spruces from destructive attack byIps typographus, while small polyethylene ampullae containing terpinene-4-ol counteract aggregation of P. chalcographus. Inhibitors appear applicable in both strategies, damage prevention as well as damage restriction, and consequently may accommodate also pest control in less intensively managed forests. Future

  18. Chirality determines pheromone activity for flour beetles

    Science.gov (United States)

    Levinson, H. Z.; Mori, K.

    1983-04-01

    Olfactory perception and orientation behaviour of female and male flour beetles ( Tribolium castaneum, T. confusum) to single stereoisomers of their aggregation pheromone revealed maximal receptor potentials and optimal attraction in response to 4R,8R-(-)-dimethyldecanal, whereas its optical antipode 4S,8S-(+)-dimethyldecanal was found to be inactive in this respect. Female flour beetles of both species were ≈ 103 times less attracted to 4R,8S-(+)- and 4S,8R-(-)-dimethyldecanal than to 4R,8R-(-)-dimethyldecanal, while male flour beetles failed to respond to the R,S-(+)- and S,R-(-)-stereoisomers. Pheromone extracts of prothoracic femora from unmated male flour beetles elicited higher receptor potentials in the antennae of females than in those of males. The results suggest that the aggregation pheromone emitted by male T. castaneum as well as male T. confusum has the stereochemical structure of 4R,8R-(-)-dimethyl-decanal, which acts as sex attractant for the females and as aggregant for the males of both species.

  19. Bark beetle management guidebook

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This guidebook is designed to provide a background to bark beetle management practices consistent with the British Columbia Forest Practices Code, as well as specific practices for managing mountain pine beetle (Dendroctonus ponderosae), spruce beetle (Dendroctonus rufipennis), and Douglas-fir beetle (Dendroctonus pseudotsugae). It describes their general biology and distribution in British Columbia, their life cycles and population dynamics, and symptoms of bark beetle attack. General management strategies presented include prevention (a long-term approach), suppression, holding actions, and salvage. Strategies appropriate to specific bark beetles include aerial surveys, ground detection, baiting, harvesting, and use of insecticides. The guidebook includes brief mention of other bark beetles (Scolytids and other Dendroctonus species) and a glossary.

  20. The bacterial community of entomophilic nematodes and host beetles.

    Science.gov (United States)

    Koneru, Sneha L; Salinas, Heilly; Flores, Gilberto E; Hong, Ray L

    2016-05-01

    Insects form the most species-rich lineage of Eukaryotes and each is a potential host for organisms from multiple phyla, including fungi, protozoa, mites, bacteria and nematodes. In particular, beetles are known to be associated with distinct bacterial communities and entomophilic nematodes. While entomopathogenic nematodes require symbiotic bacteria to kill and reproduce inside their insect hosts, the microbial ecology that facilitates other types of nematode-insect associations is largely unknown. To illuminate detailed patterns of the tritrophic beetle-nematode-bacteria relationship, we surveyed the nematode infestation profiles of scarab beetles in the greater Los Angeles area over a five-year period and found distinct nematode infestation patterns for certain beetle hosts. Over a single season, we characterized the bacterial communities of beetles and their associated nematodes using high-throughput sequencing of the 16S rRNA gene. We found significant differences in bacterial community composition among the five prevalent beetle host species, independent of geographical origin. Anaerobes Synergistaceae and sulphate-reducing Desulfovibrionaceae were most abundant in Amblonoxia beetles, while Enterobacteriaceae and Lachnospiraceae were common in Cyclocephala beetles. Unlike entomopathogenic nematodes that carry bacterial symbionts, insect-associated nematodes do not alter the beetles' native bacterial communities, nor do their microbiomes differ according to nematode or beetle host species. The conservation of Diplogastrid nematodes associations with Melolonthinae beetles and sulphate-reducing bacteria suggests a possible link between beetle-bacterial communities and their associated nematodes. Our results establish a starting point towards understanding the dynamic interactions between soil macroinvertebrates and their microbiota in a highly accessible urban environment. PMID:26992100

  1. The Spruce Beetle

    OpenAIRE

    Holsten, E H; Their, R W; Munson, A. S.; Gibson, K.E.

    1999-01-01

    The spruce beetle, Dendroctonus rufipennis (Kirby), is the most significant natural mortality agent of mature spruce. Outbreaks of this beetle have caused extensive spruce mortality from Alaska to Arizona and have occurred in every forest with substantial spruce stands. Spruce beetle damage results in the loss of 333 to 500 million board feet of spruce saw timber annually. More than 2.3 million acres of spruce forests have been infested in Alaska in the last 7 years with an estimated 30 milli...

  2. Control of Chinese rose beetle (Coleoptera: Scarabaeidae) through the use of solar-powered nighttime illumination

    Science.gov (United States)

    Chinese rose beetle, Adoretus sinicus (Burmeister), a scarab beetle found in Asia and the Pacific Islands, was first reported in Hawaii in 1891. Adults feed at night on leaves of a wide range of plant species, including many that are economically important. Aggregate feeding can stunt or even kill ...

  3. Predaceous diving beetles in Maine: Faunal list and keys to subfamilies

    Science.gov (United States)

    Boobar, L.R.; Spangler, P.J.; Gibbs, K.E.; Longcore, J.R.; Hopkins, K.M.

    1998-01-01

    Records of predaceous diving beetles (Coleoptera: Dytiscidae) collected in Maine are summarized. These records are augmented by field surveys of beetles in Aroostook Co., Maine during 1993-95. Keys to subfamilies are presented with color plates for selected species. A list of diving beetles that have been collected near Maine (state or province) is presented so that investigators will know what additional species might be expected in Maine. Basic taxonomy is presented to facilitate use of keys.

  4. Localized spatial and temporal attack dynamics of the mountain pine beetle in lodgepole pine. Forest Service research paper

    Energy Technology Data Exchange (ETDEWEB)

    Bentz, B.J.; Powell, J.A.; Logan, J.A.

    1996-12-01

    Colonization of a host tree by the mountain pine beetle (Dendroctonus ponderosae) involves chemical communication that enables a massive aggregation of beetles on a single resource, thereby ensuring host death and subsequent beetle population survival. Beetle populations have evolved a mechanism for termination of colonization on a lodgepole pine tree at optimal beetle densities, with a concomitant switch of attacks to nearby trees. Observations of the daily spatial and temporal attack process of mountain pine beetles (nonepidemic) attacking lodgepole pine suggest that beetles switch attacks to a new host tree before the original focus tree is fully colonized, and that verbenone, an antiaggregating pheromone, may be acting within a tree rather than between trees.

  5. Ascarosides coordinate the dispersal of a plant-parasitic nematode with the metamorphosis of its vector beetle.

    Science.gov (United States)

    Zhao, Lilin; Zhang, Xinxing; Wei, Yanan; Zhou, Jiao; Zhang, Wei; Qin, Peijun; Chinta, Satya; Kong, Xiangbo; Liu, Yunpeng; Yu, Haiying; Hu, Songnian; Zou, Zhen; Butcher, Rebecca A; Sun, Jianghua

    2016-01-01

    Insect vectors are required for the transmission of many species of parasitic nematodes, but the mechanisms by which the vectors and nematodes coordinate their life cycles are poorly understood. Here, we report that ascarosides, an evolutionarily conserved family of nematode pheromones, are produced not only by a plant-parasitic nematode, but also by its vector beetle. The pinewood nematode and its vector beetle cause pine wilt disease, which threatens forest ecosystems world-wide. Ascarosides secreted by the dispersal third-stage nematode LIII larvae promote beetle pupation by inducing ecdysone production in the beetle and up-regulating ecdysone-dependent gene expression. Once the beetle develops into the adult stage, it secretes ascarosides that attract the dispersal fourth-stage nematode LIV larvae, potentially facilitating their movement into the beetle trachea for transport to the next pine tree. These results demonstrate that ascarosides play a key role in the survival and spread of pine wilt disease. PMID:27477780

  6. Ascarosides coordinate the dispersal of a plant-parasitic nematode with the metamorphosis of its vector beetle

    Science.gov (United States)

    Zhao, Lilin; Zhang, Xinxing; Wei, Yanan; Zhou, Jiao; Zhang, Wei; Qin, Peijun; Chinta, Satya; Kong, Xiangbo; Liu, Yunpeng; Yu, Haiying; Hu, Songnian; Zou, Zhen; Butcher, Rebecca A.; Sun, Jianghua

    2016-01-01

    Insect vectors are required for the transmission of many species of parasitic nematodes, but the mechanisms by which the vectors and nematodes coordinate their life cycles are poorly understood. Here, we report that ascarosides, an evolutionarily conserved family of nematode pheromones, are produced not only by a plant-parasitic nematode, but also by its vector beetle. The pinewood nematode and its vector beetle cause pine wilt disease, which threatens forest ecosystems world-wide. Ascarosides secreted by the dispersal third-stage nematode LIII larvae promote beetle pupation by inducing ecdysone production in the beetle and up-regulating ecdysone-dependent gene expression. Once the beetle develops into the adult stage, it secretes ascarosides that attract the dispersal fourth-stage nematode LIV larvae, potentially facilitating their movement into the beetle trachea for transport to the next pine tree. These results demonstrate that ascarosides play a key role in the survival and spread of pine wilt disease. PMID:27477780

  7. Volatile Hydrocarbon Pheromones from Beetles

    Science.gov (United States)

    This chapter reviews literature about hydrocarbons from beetles that serve as long-range pheromones. The most thoroughly studied beetles that use volatile hydrocarbon pheromones belong to the family Nitidulidae in the genera Carpophilus and Colopterus. Published pheromone research deals with behav...

  8. Colonization of disturbed trees by the southern pine bark beetle guild (Coleoptera: Scolytidae)

    Energy Technology Data Exchange (ETDEWEB)

    Flamm, R.O.; Pulley, P.E.; Coulson, R.N. (Texas A M Univ., College Station (United States))

    1993-02-01

    The southern pine bark beetle guild [Dendroctonus frontalis Zimmermann, D. terebrans (Olivier), Ips calligraphus (Germar), I. grandicollis (Eichhoff), and I. avulsus (Eichhoff)] uses disturbed hosts as habitat for establishment of within-tree populations. The process of colonization of disturbed hosts was examined. Using a procedure designed to emulate effects of a lightning strike, pines were severely disturbed. Response was characterized by measuring beetle populations that (1) arrived at the trees and (2) successfully attacked the trees. Establishment of within-tree populations was characterized by measuring length of egg gallery excavated by attacking adults. The time delay between arrival and attack for D. frontalis and I. calligraphus was also calculated. Attack densities of both species became asymptotic as arrival increased. The percentage of arriving beetles that attacked ranged from 9 to 41 for D. frontalis and from 8 to 59 for I. calligraphus. Numbers of beetles that arrived at the tree but did not attack ranged from 2.7 to 50.2 beetles per dm[sup 2] for D. frontalis and from 0.2 to 10.0 beetles per dm[sup 2] for I. calligraphus. Most D. frontalis and I. calligraphus attacked on the day they arrived. The delay between arrival and attack was longer for I. calligraphus than the D. frontalis. Egg gallery excavated by D. frontalis increased throughout the study. Eventually, the Ips species were excluded from the lower half of the hole. The low attack densities observed in this study illustrate the significance of disturbed trees in providing refuges for enzootic levels of bark beetles. The aggregation behavior of beetle populations colonizing disturbed hosts supported the contention that these trees serve as foci for initiation of infestations. Furthermore, in disturbed pines, small numbers of beetles were capable of overcoming host defense systems.

  9. Beetle wings are inflatable origami

    Science.gov (United States)

    Chen, Rui; Ren, Jing; Ge, Siqin; Hu, David

    2015-11-01

    Beetles keep their wings folded and protected under a hard shell. In times of danger, they must unfold them rapidly in order for them to fly to escape. Moreover, they must do so across a range of body mass, from 1 mg to 10 grams. How can they unfold their wings so quickly? We use high-speed videography to record wing unfolding times, which we relate to the geometry of the network of blood vessels in the wing. Larger beetles have longer unfolding times. Modeling of the flow of blood through the veins successfully accounts for the wing unfolding speed of large beetles. However, smaller beetles have anomalously short unfolding times, suggesting they have lower blood viscosity or higher driving pressure. The use of hydraulics to unfold complex objects may have implications in the design of micro-flying air vehicles.

  10. Genetics of Ophraella leaf beetles

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This proposal is to collect samples of each species of Ophraella leaf beetle encountered, not to exceed 50 specimens per species, for genetic analysis using DNA...

  11. Effect of Larval Density on Development of the Coconut Hispine Beetle, Brontispa longissima (Gestro) (Coleoptera: Chrysomelidae)

    OpenAIRE

    Mika Murata; Dang Thi Dung; Shun-ichiro Takano; Ryoko Tabata Ichiki; Satoshi Nakamura

    2012-01-01

    The coconut hispine beetle, Brontispa longissima shows, aggregation in the field. To elucidate the effect of aggregation on larval developmental aspects, we examined the effects of larval density on various aspects of larval development and on survival rates. Recently we found that B. longissima was divided into two monophyletic clades by genetic analysis. Therefore, we also compared the results between two populations, from Ishigaki, Japan (ISH) and Papua New Guinea (PNG), which were represe...

  12. Patterns of functional enzyme activity in fungus farming ambrosia beetles

    Directory of Open Access Journals (Sweden)

    De Fine Licht Henrik H

    2012-06-01

    accessible hemicellulose components of the ray-parenchyma cells in the wood xylem. Furthermore, the detection of xylanolytic enzymes exclusively in larvae (which feed on fungus colonized wood and not in adults (which feed only on fungi indicates that only larvae (pre- digest plant cell wall structures. This implies that in X. saxesenii and likely also in many other ambrosia beetles, adults and larvae do not compete for the same food within their nests - in contrast, larvae increase colony fitness by facilitating enzymatic wood degradation and fungus cultivation.

  13. JUDGMENT AGGREGATION AND PREFERENCE AGGREGATION

    OpenAIRE

    Joanna Ochremiak

    2011-01-01

    In the paper we present an introduction to the theory of judgment aggregation and discuss its relation to the theory of preference aggregation. We compare the formal model of judgment aggregation, based on logic, with the formal model of preference aggregation. Finally, we present a theorem in judgmentaggregation which is an exact analogue of Arrow's theorem for strict preferences.

  14. The Beetle Reference Manual

    CERN Document Server

    Van Bakel, N; Van den Brand, J F J; Feuerstack-Raible, M; Harnew, N; Hofmann, W; Knöpfle, K-T; Löchner, S; Schmelling, M; Sexauer, E; Smale, N J; Trunk, U; Verkooijen, H

    2001-01-01

    This paper details the port de nitions, electrical speci cations, modes of operation and programming sequences of the 128 channel readout chip Beetle . The chip is developed for the LHCb experiment and ful lls the requirements of the silicon vertex detector, the inner tracker, the pile-up veto trigger and the RICH detector in case of multianode photomultiplier readout. It integrates 128 channels with low-noise charge-sensitive preampli ers and shapers. The risetime of the shaped pulse is 25 ns with a 30% remainder of the peak voltage after 25 ns. A comparator per channel with con gurable polarity provides a binary signal. Four adjacent comparator channels are being ORed and brought o chip via LVDS ports. Either the shaper or comparator output is sampled with the LHC-bunch-crossing frequency of 40 MHz into an analogue pipeline with a programmable latency of max. 160 sampling intervalls and an integrated derandomizing bu er of 16 stages. For analog readout data is multiplexed with up to 40 MHz onto 1 or 4 ports...

  15. Anatomical localization and stereoisomeric composition of Tribolium castaneum aggregation pheromones

    Science.gov (United States)

    We report that the abdomen and associated tissues are the predominant sources of male-produced pheromones in the red flour beetle, Tribolium castaneum, and for the first time describe the stereoisomeric composition of the natural blend of isomers of the aggregation pheromone 4,8-dimethyldecanal (DMD...

  16. Impact of Forest Fragmentation on Patterns of Mountain Pine Beetle-Caused Tree Mortality

    Directory of Open Access Journals (Sweden)

    Trisalyn A. Nelson

    2013-04-01

    Full Text Available The current outbreak of mountain pine beetle, Dendroctonus ponderosae Hopkins, has led to extensive tree mortality in British Columbia and the western United States. While the greatest impacts of the outbreak have been in British Columbia, ongoing impacts are expected as the outbreak continues to spread eastward towards Canada’s boreal and eastern pine forests. Successful mitigation of this outbreak is dependent on understanding how the beetle’s host selection behaviour is influenced by the patchwork of tree mortality across the landscape. While several studies have shown that selective mechanisms operate at the individual tree level, less attention has been given to beetles’ preference for variation in spatial forest patterns, namely forest fragmentation, and if such preference changes with changing population conditions. The objective of this study is to explore the influence of fragmentation on the location of mountain pine beetle caused mortality. Using a negative binomial regression model, we tested the significance of a fragmentation measure called the Aggregation Index for predicting beetle-caused tree mortality in the central interior of British Columbia, Canada in 2000 and 2005. The results explain that mountain pine beetle OPEN ACCESS Forests 2013, 4 280 exhibit a density-dependent dynamic behaviour related to forest patterns, with fragmented forests experiencing greater tree mortality when beetle populations are low (2000. Conversely, more contiguous forests are preferred when populations reach epidemic levels (2005. These results reinforce existing findings that bark beetles exhibit a strong host configuration preference at low population levels and that such pressures are relaxed when beetle densities are high.

  17. Rational Aggregation

    OpenAIRE

    Bruce Chapman

    2002-01-01

    In two recent papers, Christian List and Philip Pettit have argued that there is a problem in the aggregation of reasoned judgements that is akin to the aggregation of the preference problem in social choice theory.1 Indeed, List and Pettit prove a new general impossibility theorem for the aggregation of judgements, and provide a propositional interpretation of the social choice problem that suggests it is a special case of their impossibility result.2 Specifically, they show that no judgemen...

  18. Trade Facilitation

    OpenAIRE

    Ujiie, Teruo

    2006-01-01

    The issue of trade facilitation has been increasingly highlighted among business and trading communities as they would like to reduce the costs of international transactions of goods and services. Trade facilitation is a broad term: there are a number of international agreements relating to trade facilitation, and a number of international organizations involved in this area. Recognizing the importance of trade facilitation and after several years of exploratory work on government trade facil...

  19. Bacterial and fungal symbionts of parasitic Dendroctonus bark beetles.

    Science.gov (United States)

    Dohet, Loïc; Grégoire, Jean-Claude; Berasategui, Aileen; Kaltenpoth, Martin; Biedermann, Peter H W

    2016-09-01

    Bark beetles (Curculionidae: Scolytinae) are one of the most species-rich herbivorous insect groups with many shifts in ecology and host-plant use, which may be mediated by their bacterial and fungal symbionts. While symbionts are well studied in economically important, tree-killing species, little is known about parasitic species whose broods develop in living trees. Here, using culture-dependent and independent methods, we provide a comprehensive overview of the associated bacteria, yeasts and filamentous fungi of the parasitic Dendroctonus micans, D. punctatus and D. valens, and compare them to those of other tree-inhabiting insects. Despite inhabiting different geographical regions and/or host trees, the three species showed similar microbial communities. Enterobacteria were the most prevalent bacteria, in particular Rahnella, Pantoea and Ewingella, in addition to Streptomyces Likewise, the yeasts Candida/Cyberlindnera were the most prominent fungi. All these microorganisms are widespread among tree-inhabiting insects with various ecologies, but their high prevalence overall might indicate a beneficial role such as detoxification of tree defenses, diet supplementation or protection against pathogens. As such, our results enable comparisons of symbiont communities of parasitic bark beetles with those of other beetles, and will contribute to our understanding of how microbial symbioses facilitate dietary shifts in insects. PMID:27387908

  20. Approaches to engineer stability of beetle luciferases

    OpenAIRE

    Mikhail Koksharov; Natalia Ugarova

    2012-01-01

    Luciferase enzymes from fireflies and other beetles have many important applications in molecular biology, biotechnology, analytical chemistry and several other areas. Many novel beetle luciferases with promising properties have been reported in the recent years. However, actual and potential applications of wild-type beetle luciferases are often limited by insufficient stability or decrease in activity of the enzyme at the conditions of a particular assay. Various examples of genetic enginee...

  1. Weighted aggregation

    Science.gov (United States)

    Feiveson, A. H. (Principal Investigator)

    1979-01-01

    The use of a weighted aggregation technique to improve the precision of the overall LACIE estimate is considered. The manner in which a weighted aggregation technique is implemented given a set of weights is described. The problem of variance estimation is discussed and the question of how to obtain the weights in an operational environment is addressed.

  2. Aggregate productivity and aggregate technology

    OpenAIRE

    Susanto Basu; John G. Fernald

    1997-01-01

    Aggregate productivity and aggregate technology are meaningful but distinct concepts. We show that a slightly-modified Solow productivity residual measures changes in economic welfare, even when productivity and technology differ because of distortions such as imperfect competition. We then present a general accounting framework that identifies several new non-technological gaps between productivity and technology, gaps reflecting imperfections and frictions in output and factor markets. Empi...

  3. The lodgepole × jack pine hybrid zone in Alberta, Canada: a stepping stone for the mountain pine beetle on its journey East across the boreal forest?

    Science.gov (United States)

    Lusebrink, Inka; Erbilgin, Nadir; Evenden, Maya L

    2013-09-01

    Historical data show that outbreaks of the tree killing mountain pine beetle are often preceded by periods of drought. Global climate change impacts drought frequency and severity and is implicated in the range expansion of the mountain pine beetle into formerly unsuitable habitats. Its expanded range has recently reached the lodgepole × jack pine hybrid zone in central Alberta, Canada, which could act as a transition from its historical lodgepole pine host to a jack pine host present in the boreal forest. This field study tested the effects of water limitation on chemical defenses of mature trees against mountain pine beetle-associated microorganisms and on beetle brood success in lodgepole × jack pine hybrid trees. Tree chemical defenses as measured by monoterpene emission from tree boles and monoterpene concentration in needles were greater in trees that experienced water deficit compared to well-watered trees. Myrcene was identified as specific defensive compound, since it significantly increased upon inoculation with dead mountain pine beetles. Beetles reared in bolts from trees that experienced water deficit emerged with a higher fat content, demonstrating for the first time experimentally that drought conditions benefit mountain pine beetles. Further, our study demonstrated that volatile chemical emission from tree boles and phloem chemistry place the hybrid tree chemotype in-between lodgepole pine and jack pine, which might facilitate the host shift from lodgepole pine to jack pine. PMID:23955061

  4. US Forest Service Western Bark Beetle Strategy

    Data.gov (United States)

    US Forest Service, Department of Agriculture — A map service on the www depicting Western Bark Beetle Strategy (WBBS) activities reported through the U.S. Forest Service FACTS database. Activities include...

  5. Approaches to engineer stability of beetle luciferases

    Directory of Open Access Journals (Sweden)

    Mikhail Koksharov

    2012-09-01

    Full Text Available Luciferase enzymes from fireflies and other beetles have many important applications in molecular biology, biotechnology, analytical chemistry and several other areas. Many novel beetle luciferases with promising properties have been reported in the recent years. However, actual and potential applications of wild-type beetle luciferases are often limited by insufficient stability or decrease in activity of the enzyme at the conditions of a particular assay. Various examples of genetic engineering of the enhanced beetle luciferases have been reported that successfully solve or alleviate many of these limitations. This mini-review summarizes the recent advances in development of mutant luciferases with improved stability and activity characteristics. It discusses the common limitations of wild-type luciferases in different applications and presents the efficient approaches that can be used to address these problems.

  6. American burying beetle site records : Valentine NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is specific site records of American burying beetle on Valentine Nationl Wildlife Refuge to date. It includes a map of site location. A discussion...

  7. Cucurbitacins as kairomones for diabroticite beetles.

    Science.gov (United States)

    Metcalf, R L; Metcalf, R A; Rhodes, A M

    1980-07-01

    The characteristic bitter substances of the Cucurbitaceae act as kairomones for a large group of diabroticite beetles (Chrysomelidae, Galerucinae, Luperini), promoting host selection and compulsive feeding behavior. These beetles (e.g., Diabrotica undecimpunctata howardi) respond to as little as 1 ng of cucurbitacin (Cuc) B on thin-layer plates by arrest and compulsive feeding. Six species of diabroticite beetles were about 10 times more responsive to Cuc B than to Cuc E and less responsive to Cuc D, I, and L. Chloroform extracts of 18 species of Cucurbita were developed on thin-layer chromatograms and exposed to diabroticite beetles. The feeding patterns showed pronounced beetle responses to three general Cuc distribution patterns: Cuc B and D as in Cucurbita andreana and C. ecuadorensis; Cuc E and I as in C. okeechobeensis and C. martinezii; and Cuc E glycoside in C. texana. All the diabroticites responded in exactly the same feeding patterns. The results demonstrate a coevolutionary association between the Cucurbitaceae and the Luperini, during which the intensely bitter and toxic Cucs that arose to repel herbivores and protect the plants from attack became specific kairomone feeding stimulants for the beetles. PMID:16592849

  8. Colorado potato beetle manipulates plant defenses in local and systemic leaves

    OpenAIRE

    Chung, Seung Ho; Rosa, Cristina; Hoover, Kelli; Luthe, Dawn S; Felton, Gary W.

    2013-01-01

    Herbivore microbial associates can affect diverse interactions between plants and insect herbivores. Some insect symbionts enable herbivores to expand host plant range or to facilitate host plant use by modifying plant physiology. However, little attention has been paid to the role of herbivore-associated microbes in manipulating plant defenses. We have recently shown that Colorado potato beetle secrete the symbiotic bacteria to suppress plant defenses. The bacteria in oral secretions from th...

  9. Semiochemical emission from individual galleries of the southern pine beetle, (Coleoptera: Curculionidae: Scolytinae), attacking standing trees.

    Science.gov (United States)

    Pureswaran, Deepa S; Sullivan, Brian T

    2012-02-01

    We collected, identified, and quantified volatiles arising from individual gallery entrances of the monogamous bark beetle Dendroctonus frontalis Zimmermann. Samples were collected while the insects were mass attacking mature loblolly pines (Pinus taeda L.) in an established infestation in western Mississippi, 1 August through 3 October 2005. Following volatile sample collection, the entrances were dissected and categorized according to those that 1) contained a solitary female (the gallery initiating sex), 2) contained a pair that had not yet produced an egg gallery, 3) led to an egg gallery with niches and/or eggs, or 4) represented failed attacks (either abandoned or containing dead beetles). The greatest mean release rate of the female-produced aggregation pheromone components frontalin (74 ng/h) and trans-verbenol (0.35 microg/h) was detected from entrances of solitary females, whereas the highest mean quantities of the male-produced multifunctional pheromone components endo-brevicomin (18 ng/h) and verbenone (0.15 microg/h) were detected from entrances of preoviposition beetle pairs. Alpha-pinene, a host-produced monoterpene that functions as a synergist for the aggregation attractant for D. frontalis, was detected from entrances of solitary females and preoviposition pairs at a rate of 0.6 mg/h, or 3-4 orders of magnitude greater than the insect-produced components of the attractant. Our results indicate that the release rates of pheromone components used in published field studies of the chemical ecology of D. frontalis (generally > 0.1 mg/h) represent thousands of 'attack equivalents' or production rates on the scale of a beetle mass attack on a single host. Additionally, our data suggest that the loss in attractiveness of host tissue fully colonized by D. frontalis is because of the disappearance of attractants rather than an increase in inhibitors. PMID:22420266

  10. Volatile emissions from the lesser mealworm beetle Alphitobius diaperinus

    Science.gov (United States)

    The lesser mealworm beetle Alphitobius diaperinus (Panzer) is a serious, cosmopolitan pest in poultry production facilities, consuming grain, carrying disease organisms, and causing structural damage in poultry house walls. Pheromones have been described for many economically important beetle speci...

  11. Small hive beetles survive in honeybee prisons by behavioural mimicry

    Science.gov (United States)

    Ellis, J. D.; Pirk, C. W. W.; Hepburn, H. R.; Kastberger, G.; Elzen, P. J.

    2002-05-01

    We report the results of a simple experiment to determine whether honeybees feed their small hive beetle nest parasites. Honeybees incarcerate the beetles in cells constructed of plant resins and continually guard them. The longevity of incarcerated beetles greatly exceeds their metabolic reserves. We show that survival of small hive beetles derives from behavioural mimicry by which the beetles induce the bees to feed them trophallactically. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at htpp://dx.doi.org/10.1007/s00114-002-0326-y.

  12. Egg Predation by the Introduced Lady Beetle, Coccinella septempunctata (Coleoptera: Coccinellidae, Lowers Mortality but Raises Relative Risk for the Native Lady Beetle, Coccinella novemnotata.

    Directory of Open Access Journals (Sweden)

    Rakim Turnipseed

    Full Text Available Populations of the native ninespotted lady beetle, Coccinella novemnotata Herbst, have undergone precipitous declines in North America following the establishment of the exotic sevenspotted lady beetle, Coccinella septempunctata L. Recent volunteer efforts have made it possible to establish colonies of the now-rare C. novemnotata and test mechanisms contributing to its decline. We evaluated the relative frequencies of intraguild predation and cannibalism of eggs between these two species. A single C. novemnotata or C. septempunctata adult was exposed to conspecific and heterospecific eggs in either the presence or absence of pea aphids. The study revealed two expected results: 1 eggs of C. novemnotata were consumed more frequently than eggs of C. septempunctata by both species, and 2 egg consumption was higher when aphids were absent, independent of predator and egg species. There were also two unexpected results from the study: 1 the asymmetry between egg predation rates was higher when aphids were present, and 2 higher predation rates on C. novemnotata eggs in the absence of alternate prey was due to a relatively higher rate of intraspecific cannibalism. This implies that C. novemnotata would have suffered higher egg mortality rates before the invasion of C. septempunctata, but even though the aggregate rate of egg predation on C. novemnotata eggs is lower post-invasion, it is still significantly higher than the aggregate rate of predation of C. septempunctata eggs. This differential pattern of asymmetric predation could contribute to habitat compression and the overall decline of C. novemnotata.

  13. Dispersal of the spruce beetle, `dendroctonus rufipennis`, and the engraver beetle, `ips perturbatus`, in Alaska. Forest Service research paper

    Energy Technology Data Exchange (ETDEWEB)

    Werner, R.A.; Holsten, E.H.

    1997-09-01

    Mark-release-recapture experiments were performed with spruce beetles (Dendroctonus rufipennis (Kirby)) and Ips engraver beetles (Ips perturbatus (Eichhoff)) to determine distance and direction of dispersal. The recapture rate of beetles marked with fluorescent powder was extremely low. Most I. perturbatus beetles dispersed up to 30 m from their overwintering sites compared to most D. rufipennis, which dispersed from 90 to 300 m. Ips perturbatus beetles were caught up to 90 m and D. rufipennis up to 600 m from the point of release.

  14. Mountain pine beetles colonizing historical and naive host trees are associated with a bacterial community highly enriched in genes contributing to terpene metabolism.

    Science.gov (United States)

    Adams, Aaron S; Aylward, Frank O; Adams, Sandye M; Erbilgin, Nadir; Aukema, Brian H; Currie, Cameron R; Suen, Garret; Raffa, Kenneth F

    2013-06-01

    The mountain pine beetle, Dendroctonus ponderosae, is a subcortical herbivore native to western North America that can kill healthy conifers by overcoming host tree defenses, which consist largely of high terpene concentrations. The mechanisms by which these beetles contend with toxic compounds are not well understood. Here, we explore a component of the hypothesis that beetle-associated bacterial symbionts contribute to the ability of D. ponderosae to overcome tree defenses by assisting with terpene detoxification. Such symbionts may facilitate host tree transitions during range expansions currently being driven by climate change. For example, this insect has recently breached the historical geophysical barrier of the Canadian Rocky Mountains, providing access to näive tree hosts and unprecedented connectivity to eastern forests. We use culture-independent techniques to describe the bacterial community associated with D. ponderosae beetles and their galleries from their historical host, Pinus contorta, and their more recent host, hybrid P. contorta-Pinus banksiana. We show that these communities are enriched with genes involved in terpene degradation compared with other plant biomass-processing microbial communities. These pine beetle microbial communities are dominated by members of the genera Pseudomonas, Rahnella, Serratia, and Burkholderia, and the majority of genes involved in terpene degradation belong to these genera. Our work provides the first metagenome of bacterial communities associated with a bark beetle and is consistent with a potential microbial contribution to detoxification of tree defenses needed to survive the subcortical environment. PMID:23542624

  15. Aggregation of Scale Efficiency

    OpenAIRE

    Valentin Zelenyuk

    2012-01-01

    In this article we extend the aggregation theory in efficiency and productivity analysis by deriving solutions to the problem of aggregation of individual scale efficiency measures, primal and dual, into aggregate primal and dual scale efficiency measures of a group. The new aggregation result is coherent with aggregation framework and solutions for the other related efficiency measures that already exist in the literature.

  16. ProADD: A database on Protein Aggregation Diseases

    OpenAIRE

    Shobana, Ramesh; Pandaranayaka, Eswari PJ

    2014-01-01

    ProADD, a database for protein aggregation diseases, is developed to organize the data under a single platform to facilitate easy access for researchers. Diseases caused due to protein aggregation and the proteins involved in each of these diseases are integrated. The database helps in classification of proteins involved in the protein aggregation diseases based on sequence and structural analysis. Analysis of proteins can be done to mine patterns prevailing among the aggregating proteins. Av...

  17. Pathogens, promising candidates for bark beetle control

    Czech Academy of Sciences Publication Activity Database

    Wegensteiner, R.; Weiser, Jaroslav

    Georgetown: International Union of Forestry Research Organizations., 2003. s. 35. [Integrated Control of Scolytid Bark Beetles.. 29.09.2003-02.10.2003, Georgetown] Institutional research plan: CEZ:AV0Z5007907 Keywords : Rhizopoda * Sporozoa Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection

  18. Molecular phylogeny of beetle associated diplogastrid nematodes suggests host switching rather than nematode-beetle coevolution

    Directory of Open Access Journals (Sweden)

    Sommer Ralf J

    2009-08-01

    Full Text Available Abstract Background Nematodes are putatively the most species-rich animal phylum. They have various life styles and occur in a variety of habitats, ranging from free-living nematodes in aquatic or terrestrial environments to parasites of animals and plants. The rhabditid nematode Caenorhabditis elegans is one of the most important model organisms in modern biology. Pristionchus pacificus of the family of the Diplogastridae has been developed as a satellite model for comparison to C. elegans. The Diplogastridae, a monophyletic clade within the rhabditid nematodes, are frequently associated with beetles. How this beetle-association evolved and whether beetle-nematode coevolution occurred is still elusive. As a prerequisite to answering this question a robust phylogeny of beetle-associated Diplogastridae is needed. Results Sequences for the nuclear small subunit ribosomal RNA and for 12 ribosomal protein encoding nucleotide sequences were collected for 14 diplogastrid taxa yielding a dataset of 5996 bp of concatenated aligned sequences. A molecular phylogeny of beetle-associated diplogastrid nematodes was established by various algorithms. Robust subclades could be demonstrated embedded in a phylogenetic tree topology with short internal branches, indicating rapid ancestral divergences. Comparison of the diplogastrid phylogeny to a comprehensive beetle phylogeny revealed no major congruence and thus no evidence for a long-term coevolution. Conclusion Reconstruction of the phylogenetic history of beetle-associated Diplogastridae yields four distinct subclades, whose deep phylogenetic divergence, as indicated by short internal branch lengths, shows evidence for evolution by successions of ancient rapid radiation events. The stem species of the Diplogastridae existed at the same time period when the major radiations of the beetles occurred. Comparison of nematode and beetle phylogenies provides, however, no evidence for long-term coevolution of

  19. Species-specific defence responses facilitate conspecifics and inhibit heterospecifics in above–belowground herbivore interactions

    OpenAIRE

    Huang, Wei; Siemann, Evan; Xiao, Li; Yang, Xuefang; Ding, Jianqing

    2014-01-01

    Conspecific and heterospecific aboveground and belowground herbivores often occur together in nature and their interactions may determine community structure. Here we show how aboveground adults and belowground larvae of the tallow tree specialist beetle Bikasha collaris and multiple heterospecific aboveground species interact to determine herbivore performance. Conspecific aboveground adults facilitate belowground larvae, but other aboveground damage inhibits larvae or has no effect. Belowgr...

  20. Confinement of small hive beetles (Aethina tumida) by Cape honeybees (Apis mellifera capensis)

    OpenAIRE

    James D. Ellis Jr.,; Hepburn, Randall; Elzen, Patti

    2004-01-01

    International audience In this study we quantify small hive beetle (Aethina tumida Murray) and Cape honeybee (A.m. capensis Esch., an African subspecies) behaviours that are associated with beetle confinement in an effort to understand why Cape bees can withstand large beetle infestations. Four observation hives were each inoculated with 25 beetles and were observed for 11-17 days. Data collected included guard bee (worker bees who guard beetle confinement sites) and confined beetle behavi...

  1. Novel family of terpene synthases evolved from trans-isoprenyl diphosphate synthases in a flea beetle.

    Science.gov (United States)

    Beran, Franziska; Rahfeld, Peter; Luck, Katrin; Nagel, Raimund; Vogel, Heiko; Wielsch, Natalie; Irmisch, Sandra; Ramasamy, Srinivasan; Gershenzon, Jonathan; Heckel, David G; Köllner, Tobias G

    2016-03-15

    Sesquiterpenes play important roles in insect communication, for example as pheromones. However, no sesquiterpene synthases, the enzymes involved in construction of the basic carbon skeleton, have been identified in insects to date. We investigated the biosynthesis of the sesquiterpene (6R,7S)-himachala-9,11-diene in the crucifer flea beetle Phyllotreta striolata, a compound previously identified as a male-produced aggregation pheromone in several Phyllotreta species. A (6R,7S)-himachala-9,11-diene-producing sesquiterpene synthase activity was detected in crude beetle protein extracts, but only when (Z,E)-farnesyl diphosphate [(Z,E)-FPP] was offered as a substrate. No sequences resembling sesquiterpene synthases from plants, fungi, or bacteria were found in the P. striolata transcriptome, but we identified nine divergent putative trans-isoprenyl diphosphate synthase (trans-IDS) transcripts. Four of these putative trans-IDSs exhibited terpene synthase (TPS) activity when heterologously expressed. Recombinant PsTPS1 converted (Z,E)-FPP to (6R,7S)-himachala-9,11-diene and other sesquiterpenes observed in beetle extracts. RNAi-mediated knockdown of PsTPS1 mRNA in P. striolata males led to reduced emission of aggregation pheromone, confirming a significant role of PsTPS1 in pheromone biosynthesis. Two expressed enzymes showed genuine IDS activity, with PsIDS1 synthesizing (E,E)-FPP, whereas PsIDS3 produced neryl diphosphate, (Z,Z)-FPP, and (Z,E)-FPP. In a phylogenetic analysis, the PsTPS enzymes and PsIDS3 were clearly separated from a clade of known coleopteran trans-IDS enzymes including PsIDS1 and PsIDS2. However, the exon-intron structures of IDS and TPS genes in P. striolata are conserved, suggesting that this TPS gene family evolved from trans-IDS ancestors. PMID:26936952

  2. Characteristics of the tensile mechanical properties of fresh and dry forewings of beetles.

    Science.gov (United States)

    Tuo, Wanyong; Chen, Jinxiang; Wu, Zhishen; Xie, Juan; Wang, Yong

    2016-08-01

    Based on a tensile experiment and observations by scanning electron microscopy (SEM), this study demonstrated the characteristics of the tensile mechanical properties of the fresh and dry forewings of two types of beetles. The results revealed obvious differences in the tensile fracture morphologies and characteristics of the tensile mechanical properties of fresh and dry forewings of Cybister tripunctatus Olivier and Allomyrina dichotoma. For fresh forewings of these two types of beetles, a viscous, flow-like, polymer matrix plastic deformation was observed on the fracture surfaces, with soft morphologies and many fibers being pulled out, whereas on the dry forewings, the tensile fracture surfaces were straightforward, and there were no features resembling those found on the fresh forewings. The fresh forewings exhibited a greater fracture strain than the dry forewings, which was caused by the relative slippage of hydroxyl inter-chain bonds due to the presence of water in the fibers and proteins in the fresh forewings. Our study is the first to demonstrate the phenomenon of sudden stress drops caused by the fracturing of the lower skin because the lower skin fractured before the forewings of A. dichotoma reached their ultimate tensile strength. We also investigated the reasons underlying this phenomenon. This research provides a much better understanding of the mechanical properties of beetle forewings and facilitates the correct selection of study objects for biomimetic materials and development of the corresponding applications. PMID:27157727

  3. Dung beetle database: comparison with other invertebrate transcriptomes

    OpenAIRE

    Khanyile, Lucky M; Hull, Rodney; Ntwasa, Monde

    2008-01-01

    The dung beetle E. intermedius, a member of the highly diverse order, Coleoptera has immense economic benefits. It was estimated that insect ecological services in the United States amounted to some $60 billion in 2006 with dung beetles being major contributors. E. intermedius may be endowed with a robust immune system given its microbe-rich habitat. Dung beetles live on juice and microbes from the dung and are therefore, potential models for the study of infectious agents and ecological dama...

  4. Dutch elm disease and elm bark beetles: a century of association

    Directory of Open Access Journals (Sweden)

    Santini A

    2015-04-01

    Full Text Available Bark beetles of the genus Scolytus Geoffroy are the main vectors of the fungus Ophiostoma ulmi s.l., which causes the Dutch elm disease. The large and small elm bark beetles - S. scolytus (F. and S. multistriatus (Marsham, respectively - are the most common and important species spreading the pathogen worldwide. The success of the pathogen-insect interactions is mainly due to the characteristic reproductive behavior of the elm bark beetles, which, however, largely depends on the occurrence of infected trees. During feeding activity on elm twigs, callow adults carrying pathogen conidia on their bodies contaminate healthy trees and facilitate pathogen development and movement within the wood vessels. Infected trees become then suitable for insect breeding in the stem bark. This well-known mutualistic association has devastating consequences for elm survival. Although much is known about insect-pathogen interactions and transmission mechanisms, many topics still deserve additional attention, as, for example, beetle systematic based on new molecular tools and morphological characters; selection of European elm clones based on disease avoidance; consequences of global warming on life-history of the three organisms (fungus-insect-tree involved in the pathosystem; new problems resulting from the rapid increase of international trade among continents, leading to the accidental introduction of new vector species or new pathogen species or races, or to the introduction of new highly susceptible elm species in gardens and public parks. A holistic approach to tackle the problem is highly recommended, taking into account how these organisms interact with each other and the environment, and how their interactions could be modified in order to face one of the most destructive diseases ever known in plant pathology.

  5. Consistent Trade Policy Aggregation

    OpenAIRE

    Anderson, James E.

    2008-01-01

    Much empirical work requires the aggregation of policies. This paper provides methods of policy aggregation that are consistent with two common objectives of empirical work. One is to preserve real income. The other is to preserve the real volume of activity in one or more parts of the economy. Trade policy aggregation is an acute example of the aggregation problem with thousands of highly dispersed trade barriers to be aggregated. An application to India shows that the standard atheoretic me...

  6. Consistency in Aggregation

    OpenAIRE

    Ludwig Auer

    2004-01-01

    In empirical economic research, individual prices are often aggregated into average prices of sub-aggregates. Then, these average prices are aggregated to produce the average price of the total aggregate. Often, such two stage procedures help to illuminate the underlying forces driving the overall result. Since price data are usually published as price changes, this two stage aggregation is typically based on some price index formula. In this paper, various screening devices are introduced wh...

  7. Information-aggregation bias

    OpenAIRE

    Goodfriend, Marvin

    1991-01-01

    Aggregation in the presence of data-processing lags distorts the information content of data, violating orthogonality restrictions that hold at the individual level. Though the phenomenon is general, it is illustrated here for the life-cycle-permanent-income model. Cross-section and pooled-panel data induce information-aggregation bias akin to that in aggregate time series. Calculations show that information aggregation can seriously bias tests of the life-cycle model on aggregate time series...

  8. Evolution of exocrine chemical defense in leaf beetles (Coleoptera: Chrysomelidae)

    OpenAIRE

    Pasteels, Jacques M.; Rowell-Rahier, Martine; Braekman, J.C.; Daloze, D.; Duffey, S.

    2009-01-01

    In this review we speculate on possible scenarios for the evolution of the very high diversity in chemical compounds liberated by exocrine glands of adults Chrysomelidae. Shift in host plant affinities and subsequent adaptation of the beetles to the plant toxins strongly influence the nature of the beetles' chemical defense.

  9. Cucumber Beetle Antifeedants: Laboratory Screening of Natural Products

    OpenAIRE

    Reed, D. K.; Jacobson, M.; Warthen, J. D. Jr; Uebel, E. C.; Tromley, N. J.; Jurd, L.; Freedman, B

    1981-01-01

    Cucumber beetles are destructive pests of melons in the Midwest both because of their feeding and transmission of bacterial wilt disease. Because an effective antifeedant would be an ideal control measure, more than 350 materials of biological origin have been screened against striped cucumber beetle. Such materials as neem derivatives, neriifolin, -tung, and napthoquinones appear promising and will be tested more extensively.

  10. Observations on the Life History of Small Hive Beetles

    Science.gov (United States)

    DeGuzman, L.I.& A.M. Frake. Observations on the Life History of Small Hive Beetles - The life history of small hive beetles (SHB) kept in an incubator (34ºC) and at room temperature (24-28ºC) was compared. Six slides of eggs, obtained using the glass slide technique, were placed individually in rear...

  11. Formulating entompathogens for control of boring beetles in avocado orchards

    Science.gov (United States)

    A foam formulation of Beauveria bassiana was adapted to control boring beetles in avocado orchards. The two geographically independent avocado growing areas in the United States are threatened by emerging diseases vectored by boring beetles. In the California growing region, Fusarium dieback is vect...

  12. Curcurbita pepo subspecies delineates striped cucumber beetle (Acalymma vittatum) preference

    Science.gov (United States)

    Brzozowski, L; Leckie, B M; Gardner, J; Hoffmann, M P; Mazourek, M

    2016-01-01

    The striped cucumber beetle (Acalymma vittatum (F.)) is a destructive pest of cucurbit crops, and management could be improved by host plant resistance, especially in organic farming systems. However, despite the variation in striped cucumber beetle preference observed within the economically important species, Cucurbita pepo L., plant breeders and entomologists lacked a simple framework to classify and exploit these differences. This study used recent phylogenetic evidence and bioassays to organize striped cucumber beetle preference within C. pepo. Our results indicate preference contrasts between the two agriculturally relevant subspecies: C. pepo subsp. texana and C. pepo subsp. pepo. Plants of C. pepo subsp. pepo were more strongly preferred than C. pepo subsp. texana plants. This structure of beetle preference in C. pepo will allow plant breeders and entomologists to better focus research efforts on host plant non-preference to control striped cucumber beetles. PMID:27347423

  13. Platelet aggregation test

    Science.gov (United States)

    The platelet aggregation blood test checks how well platelets , a part of blood, clump together and cause blood to clot. ... Decreased platelet aggregation may be due to: Autoimmune ... Fibrin degradation products Inherited platelet function defects ...

  14. The Zen of Facilitation.

    Science.gov (United States)

    Killion, Joellen P.; Simmons, Lynn A.

    1992-01-01

    Distinguishes between training and facilitation, examines the belief system of a facilitator, and shares a process for moving from the familiar mind-set of the trainer to the zen (the practice of seeking the truth) of facilitation. (GLR)

  15. Aggregation in manpower planning

    OpenAIRE

    Wijngaard, J

    1983-01-01

    In manpower planning, as in all other kinds of planning, an important choice is the level of aggregation. The proper level of aggregation depends on the flexibility (mobility) of the personnel. This dependency is investigated in this paper. The manpower system considered is characterized by two dimensions, level and function group. Conditions are derived for aggregate long-term planning (aggregation over function group) combined with one-period disaggregation being optimal.

  16. Aggregating Reputation Feedback

    OpenAIRE

    Garcin, Florent; Faltings, Boi; Jurca, Radu

    2009-01-01

    A fundamental task in reputation systems is to aggregate multiple feedback ratings into a single value that can be used to compare the reputation of different entities. Feedback is most commonly aggregated using the arithmetic mean. However, the mean is quite susceptible to outliers and biases, and thus may not be the most informative aggregate of the reports. We consider three criteria to assess the quality of an aggregator: the informativness, the robustness and the strategyproofness, and a...

  17. Protein aggregation and bioprocessing

    OpenAIRE

    Cromwell, Mary E. M.; Hilario, Eric; Jacobson, Fred

    2006-01-01

    Protein aggregation is a common issue encountered during manufacture of biotherapeutics. It is possible to influence the amount of aggregate produced during the cell culture and purification process by carefully controlling the environment (eg, media components) and implementing appro-priate strategies to minimize the extent of aggregation. Steps to remove aggregates have been successfully used at a manufacturing scale. Care should be taken when developing a process to monitor the compatibili...

  18. Epicuticular lipids induce aggregation in Chagas disease vectors

    OpenAIRE

    Juárez M Patricia; Mijailovsky Sergio J; Girotti Juan R; Figueiras Alicia

    2009-01-01

    Abstract Background The triatomine bugs are vectors of the protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. Aggregation behavior plays an important role in their survival by facilitating the location of refuges and cohesion of aggregates, helping to keep them safely assembled into shelters during daylight time, when they are vulnerable to predators. There are evidences that aggregation is mediated by thigmotaxis, by volatile cues from their faeces, and by hexane-ex...

  19. Spruce Beetle Biology, Ecology and Management in the Rocky Mountains: An Addendum to Spruce Beetle in the Rockies

    Directory of Open Access Journals (Sweden)

    Michael J. Jenkins

    2014-01-01

    Full Text Available Spruce beetle outbreaks have been reported in the Rocky Mountains of western North America since the late 1800s. In their classic paper, Spruce Beetle in the Rockies, Schmid and Frye reviewed the literature that emerged from the extensive outbreaks in Colorado in the 1940s. A new wave of outbreaks has affected Rocky Mountain subalpine spruce-fir forests beginning in the mid-1980s and continuing to the present. These outbreaks have spurred another surge of basic and applied research in the biology, ecology and management of spruce and spruce beetle populations. This paper is a review of literature on spruce beetle focusing on work published since the late 1970s and is intended as an addendum to Spruce Beetle in the Rockies.

  20. Trade-off between cellular immunity and life span in mealworm beetles Tenebrio molitor

    Institute of Scientific and Technical Information of China (English)

    Indrikis KRAMS; Jan(i)na DAUK(S)TE; Inese KIVLENIECE; Ants KAASIK; Tatjana KRAMA; Todd M.FREEBERG; Markus J.RANTALA

    2013-01-01

    Encapsulation is a nonspecific,cellular response through which insects defend themselves against multicellular pathogens.During this immune reaction,haemocytes recognize an object as foreign and cause other haemocytes to aggregate and form a capsule around the object,often consisting of melanized cells.The process of melanisation is accompanied by the formation of potentially toxic reactive oxygen species,which can kill not only pathogens but also host cells.In this study we tested whether the encapsulation response is costly in mealworm beetles Tenebrio molitor.We found a negative relationship between the duration of implantation via a nylon monofilament and remaining life span.We also found a negative relationship between the strength of immune response and remaining life span,suggesting that cellular immunity is costly in T.molitor,and that there is a trade-off between immune response and remaining life span.However,this relationship disappeared at 31-32 hours of implantation at 25 ± 2℃.As the disappearance of a relationship between duration of implantation and lifespan coincided with the highest values of encapsulation response,we concluded that the beetles stopped investment in the production of melanotic cells,as the implant,a synthetic parasite,was fully isolated from the host's tissues.

  1. Trade-off between cellular immunity and life span in mealworm beetles Tenebrio molitor

    Directory of Open Access Journals (Sweden)

    Indrikis KRAMS, Janīna DAUKŠTE, Inese KIVLENIECE, Ants KAASIK, Tatjana KRAMA, Todd M. REEBERG, Markus J. RANTALA

    2013-06-01

    Full Text Available Encapsulation is a nonspecific, cellular response through which insects defend themselves against multicellular pathogens. During this immune reaction, haemocytes recognize an object as foreign and cause other haemocytes to aggregate and form a capsule around the object, often consisting of melanized cells. The process of melanisation is accompanied by the formation of potentially toxic reactive oxygen species, which can kill not only pathogens but also host cells. In this study we tested whether the encapsulation response is costly in mealworm beetles Tenebrio molitor. We found a negative relationship between the duration of implantation via a nylon monofilament and remaining life span. We also found a negative relationship between the strength of immune response and remaining life span, suggesting that cellular immunity is costly in T. molitor, and that there is a trade-off between immune response and remaining life span. However, this relationship disappeared at 31-32 hours of implantation at 25 ± 2℃. As the disappearance of a relationship between duration of implantation and lifespan coincided with the highest values of encapsulation response, we concluded that the beetles stopped investment in the production of melanotic cells, as the implant, a synthetic parasite, was fully isolated from the host’s tissues [Current Zoology 59 (3: 340–346, 2013].

  2. Photonic nanoarchitectures of biologic origin in butterflies and beetles

    Energy Technology Data Exchange (ETDEWEB)

    Biro, L.P., E-mail: biro@mfa.kfki.h [Research Institute for Technical Physics and Materials Science, H-1525 Budapest, POB 49 (Hungary)

    2010-05-25

    Photonic nanoarchitectures occurring in butterflies and beetles, which produce structural color in the visible range of the electromagnetic spectrum by the selective reflection of light, are investigated under the aspect of being used as possible 'blueprints' for artificial, bioinspired nanoarchitectures. The role of order and disorder and of regularity/irregularity in photonic nanoarchitectures of biologic origin is discussed. Three recent case studies are briefly reviewed for butterflies (Albulina metallica, Cyanophrys remus, Troides magellanus) and three for beetles (Hoeplia coerulea, Chrysochroa vittata, Charidotella egregia). The practical realization of bioinspired artificial structures is discussed for the A. metallica butterfly and for the C. vittata beetle.

  3. Photonic nanoarchitectures of biologic origin in butterflies and beetles

    International Nuclear Information System (INIS)

    Photonic nanoarchitectures occurring in butterflies and beetles, which produce structural color in the visible range of the electromagnetic spectrum by the selective reflection of light, are investigated under the aspect of being used as possible 'blueprints' for artificial, bioinspired nanoarchitectures. The role of order and disorder and of regularity/irregularity in photonic nanoarchitectures of biologic origin is discussed. Three recent case studies are briefly reviewed for butterflies (Albulina metallica, Cyanophrys remus, Troides magellanus) and three for beetles (Hoeplia coerulea, Chrysochroa vittata, Charidotella egregia). The practical realization of bioinspired artificial structures is discussed for the A. metallica butterfly and for the C. vittata beetle.

  4. Atlas of Iberian water beetles (ESACIB database).

    Science.gov (United States)

    Sánchez-Fernández, David; Millán, Andrés; Abellán, Pedro; Picazo, Félix; Carbonell, José A; Ribera, Ignacio

    2015-01-01

    The ESACIB ('EScarabajos ACuáticos IBéricos') database is provided, including all available distributional data of Iberian and Balearic water beetles from the literature up to 2013, as well as from museum and private collections, PhD theses, and other unpublished sources. The database contains 62,015 records with associated geographic data (10×10 km UTM squares) for 488 species and subspecies of water beetles, 120 of them endemic to the Iberian Peninsula and eight to the Balearic Islands. This database was used for the elaboration of the "Atlas de los Coleópteros Acuáticos de España Peninsular". In this dataset data of 15 additional species has been added: 11 that occur in the Balearic Islands or mainland Portugal but not in peninsular Spain and an other four with mainly terrestrial habits within the genus Helophorus (for taxonomic coherence). The complete dataset is provided in Darwin Core Archive format. PMID:26448717

  5. Managing invasive populations of Asian longhorned beetle and citrus longhorned beetle: a worldwide perspective.

    Science.gov (United States)

    Haack, Robert A; Hérard, Franck; Sun, Jianghua; Turgeon, Jean J

    2010-01-01

    The Asian longhorned beetle (ALB), Anoplophora glabripennis (Motschulsky), and citrus longhorned beetle (CLB), Anoplophora chinensis (Forster) (Coleoptera: Cerambycidae), are polyphagous xylophages native to Asia and are capable of killing healthy trees. ALB outbreaks began in China in the 1980s, following major reforestation programs that used ALB-susceptible tree species. No regional CLB outbreaks have been reported in Asia. ALB was first intercepted in international trade in 1992, mostly in wood packaging material; CLB was first intercepted in 1980, mostly in live plants. ALB is now established in North America, and both species are established in Europe. After each infestation was discovered, quarantines and eradication programs were initiated to protect high-risk tree genera such as Acer, Aesculus, Betula, Populus, Salix, and Ulmus. We discuss taxonomy, diagnostics, native range, bionomics, damage, host plants, pest status in their native range, invasion history and management, recent research, and international efforts to prevent new introductions. PMID:19743916

  6. Comparative resistance of Russian and Italian honey bees (Hymenoptera: Apidae) to small hive beetles (Coleoptera: Nitidulidae).

    Science.gov (United States)

    Frake, Amanda M; De Guzman, Lilia I; Rinderer, Thomas E

    2009-02-01

    To compare resistance to small hive beetles (Coleoptera: Nitidulidae) between Russian and commercial Italian honey bees (Hymenoptera: Apidae), the numbers of invading beetles, their population levels through time and small hive beetle reproduction inside the colonies were monitored. We found that the genotype of queens introduced into nucleus colonies had no immediate effect on small hive beetle invasion. However, the influence of honey bee stock on small hive beetle invasion was pronounced once test bees populated the hives. In colonies deliberately freed from small hive beetle during each observation period, the average number of invading beetles was higher in the Italian colonies (29 +/- 5 beetles) than in the Russian honey bee colonies (16 +/- 3 beetles). A similar trend was observed in colonies that were allowed to be freely colonized by beetles throughout the experimental period (Italian, 11.46 +/- 1.35; Russian, 5.21 +/- 0.66 beetles). A linear regression analysis showed no relationships between the number of beetles in the colonies and adult bee population (r2 = 0.1034, P = 0.297), brood produced (r2 = 0.1488, P = 0.132), or amount of pollen (P = 0.1036, P = 0.295). There were more Italian colonies that supported small hive beetle reproduction than Russian colonies. Regardless of stock, the use of entrance reducers had a significant effect on the average number of small hive beetle (with reducer, 16 +/- 3; without reducer, 27 +/- 5 beetles). However, there was no effect on bee population (with reducer, 13.20 +/- 0.71; without reducer, 14.60 +/- 0.70 frames) or brood production (with reducer, 6.12 +/- 0.30; without reducer, 6.44 +/- 0.34 frames). Overall, Russian honey bees were more resistant to small hive beetle than Italian honey bees as indicated by fewer invading beetles, lower small hive beetle population through time, and lesser reproduction. PMID:19253612

  7. Provenance for Aggregate Queries

    OpenAIRE

    Yael Amsterdamer; Daniel Deutch; Val Tannen

    2011-01-01

    We study in this paper provenance information for queries with aggregation. Provenance information was studied in the context of various query languages that do not allow for aggregation, and recent work has suggested to capture provenance by annotating the different database tuples with elements of a commutative semiring and propagating the annotations through query evaluation. We show that aggregate queries pose novel challenges rendering this approach inapplicable. Consequently, we propose...

  8. Diffusion in aggregated soil.

    OpenAIRE

    Rappoldt, C.

    1992-01-01

    The structure of an aggregated soil is characterized by the distribution of the distance from an arbitrary point in the soil to the nearest macropore or crack. From this distribution an equivalent model system is derived to which a diffusion model can be more easily applied. The model system consists of spherical, or cylindrical or plane aggregates, which do not represent the individual aggregates of the soil, however. The radii of the spheres, cylinders or plane sheets represent different le...

  9. The artificial beetle, or a brief manifesto for engineered biomimicry

    Science.gov (United States)

    Bartl, Michael H.; Lakhtakia, Akhlesh

    2015-03-01

    The artificial beetle is possibly the Holy Grail for practitioners of engineered biomimicry. An artificial beetle could gather and relay data and images from compromised environments on earth and other planets to decision makers. It could also be used for surveillance of foes and friends alike, and will require ethical foresight and oversight. What would it take to develop an artificial beetle? Several biotemplating techniques can be harnessed for the replication of external structural features of beetle bodies, and thus preserve functionalities such as coloration of the exoskeleton and the hydrophobicity of wings. The body cavity must host a power supply, motors to move the wings for flight, sensors to capture ambient conditions and images, and data transmitters and receivers to communicate with a remote command center. All of these devices must be very small and reliable.

  10. Biologically inspired optics: analog semiconductor model of the beetle exoskeleton

    Science.gov (United States)

    Buhl, Kaia; Roth, Zachary; Srinivasan, Pradeep; Rumpf, Raymond; Johnson, Eric

    2008-08-01

    Evolution in nature has produced through adaptation a wide variety of distinctive optical structures in many life forms. For example, pigment differs greatly from the observed color of most beetles because their exoskeletons contain multilayer coatings. The green beetle is disguised in a surrounding leaf by having a comparable reflection spectrum as the leaves. The Manuka and June beetle have a concave structure where light incident at any angle on the concave structures produce matching reflection spectra. In this work, semiconductor processing methods were used to duplicate the structure of the beetle exoskeleton. This was achieved by combining analog lithography with a multilayer deposition process. The artificial exoskeleton, 3D concave multilayer structure, demonstrates a wide field of view with a unique spectral response. Studying and replicating these biologically inspired nanostructures may lead to new knowledge for fabrication and design of new and novel nano-photonic devices, as well as provide valuable insight to how such phenomenon is exploited.

  11. Host plant preference in Colorado potato beetle (Coleoptera: Chrysomelidae)

    Science.gov (United States)

    Field and laboratory-choice tests were conducted to better understand host plant preference by the Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae), in Virginia. In laboratory olfactometer studies, L. decemlineata preferred potato over both tomato and eggplant foli...

  12. New generic synonyms in the Oriental flea beetles (Coleoptera: Chrysomelidae)

    Science.gov (United States)

    The following new synonyms are proposed for the genera of flea beetles from Oriental Region: Pseudocrypta Medvedev, 1996 and Sebaethiella Medvedev, 1993 = Acrocrypta Baly, 1862: 457; Bhutajana Scherer, 1979 = Aphthona Chevrolat, 1836; Burmaltica Scherer, 1969 = Aphthonaltica Heikertinger, 1924; Apht...

  13. The Aggregate-Supply/Aggregate-Demand Model

    OpenAIRE

    BARRO, Robert J.

    1994-01-01

    The aggregate-supply/ aggregate-demand (AS-AD) model is popular in textbooks, but has problems with logical consistency. In one interpretation, the Keynesian underpinnings of the AD curve-derived from the IS/LM model with downward price stickiness-conflict with the determination of the price level at the intersection of the AS and AD curves. In another view, the model corresponds to rational-expectations theories in which Keynesian properties are absent. In a third interpretation, the model i...

  14. A Population Genetic Model of Evolution of Host-Mate Attraction and Nonhost Repulsion in a Bark Beetle Pityogenes bidentatus

    Directory of Open Access Journals (Sweden)

    John A. Byers

    2012-01-01

    Full Text Available Studies have shown that the bark beetle Pityogenes bidentatus (Coleoptera, Curculionidae, Scolytinae avoids volatiles of nonhost trees (Norway Spruce, birch, and oak and healthy host Scotch Pine when orienting to aggregation pheromone. A population genetic model of two behavioral genes was hypothesized where AA, Aa, and aa were allele combinations regulating orientation to host tree and pheromone odors, and BB, Bb, and bb were combinations allowing avoidance of nonhost and unsuitable host odors. The nine possible genotypes were assigned different survival factors that remained constant during simulation. The initial proportion of aabb genotype (little aggregation/host response and little avoidance of nonhosts was ~1.0 when a mutation was hypothesized that caused better orientation to host/beetle odors (Aabb and another mutation causing more efficient avoidance of nonhosts (aaBb. After these initial mutations, the model used indiscriminate mating of genotypic proportions and subsequent survival as input for each successive generation. The results indicate that AABB eventually fixates in the populations in some scenarios, while AABB and other genotypes reach stable equilibriums in other models depending on genotypic survival values supported by ecologically sound assumptions. The models indicate how development of insecticide resistance in pest insects may proceed.

  15. Bergamot versus beetle: evidence for intraspecific chemical specialization

    OpenAIRE

    Keefover-Ring, Ken

    2015-01-01

    Many plant-eating insects have developed the ability to eat plants that synthesize toxins which they use to defend themselves against herbivores. While these specialized insects are good at dealing with specific plant toxins, plant species with highly variable chemistry can present a challenge. This study tested for reciprocal effects of a specialist tortoise beetle feeding on a host plant with individuals contained two different essential oil toxins. Overall, beetles showed higher survival, ...

  16. Pulpability of beetle-killed spruce. Forest Service research paper

    Energy Technology Data Exchange (ETDEWEB)

    Scott, G.M.; Bormett, D.W.; Sutherland, N.R.; Abubakr, S.; Lowell, E.

    1996-08-01

    Infestation of the Dendroctonus rufipennis beetle has resulted in large stands of dead and dying timber on the Kenai Peninsula in Alaska. Tests were conducted to evaluate the value of beetle-killed spruce as pulpwood. The results showed that live and dead spruce wood can be pulped effectively. The two least deteriorated classes and the most deteriorated class of logs had similar characteristics when pulped; the remaining class had somewhat poorer pulpability.

  17. Chemical defense: Aquatic beetle (Dineutes hornii) vs. fish (Micropterus salmoides)

    OpenAIRE

    Eisner, Thomas; Aneshansley, Daniel J.

    2000-01-01

    Captive largemouth bass (Micropterus salmoides) reject the gyrinid beetle, Dineutes hornii. They also reject edible items (mealworms) treated by topical addition of the norsesquiterpene gyrinidal, the principal component of the defensive secretion of the beetle. The bass' oral tolerance of gyrinidal varies broadly as a function of the gyrinidal dosage and the state of satiation of the fish. When taking a D. hornii or a gyrinidal-treated mealworm in the mouth, the f...

  18. Juvenile Hormone Regulates Extreme Mandible Growth in Male Stag Beetles

    OpenAIRE

    Gotoh, Hiroki; Cornette, Richard; Koshikawa, Shigeyuki; Okada, Yasukazu; Lavine, Laura Corley; Emlen, Douglas J.; Miura, Toru

    2011-01-01

    The morphological diversity of insects is one of the most striking phenomena in biology. Evolutionary modifications to the relative sizes of body parts, including the evolution of traits with exaggerated proportions, are responsible for a vast range of body forms. Remarkable examples of an insect trait with exaggerated proportions are the mandibular weapons of stag beetles. Male stag beetles possess extremely enlarged mandibles which they use in combat with rival males over females. As with o...

  19. An Aggregation Matrix MATLAB Function

    OpenAIRE

    Caleb Stair

    2013-01-01

    This Technical Document describes the foundations for an aggregation matrix function implemented in MATLAB, including the format and structure of the required aggregation vector used as an argument to the function. The function is passed with the N-dimensional aggregation vector as an argument. The aggregation vector contains N values ranging from 1 to M, each of which is the aggregate index corresponding to the N pre-aggregation indices. The function returns an aggregation matrix with M rows...

  20. DOES CONSISTENT AGGREGATION REALLY MATTER?

    OpenAIRE

    Shumway, C. Richard; Davis, George C.

    2000-01-01

    Consistent aggregation assures that behavioral properties which apply to disaggregate relationships also apply to aggregate relationships. The agricultural economics literature is reviewed which has tested for consistent aggregation or measured statistical bias and/or inferential errors due to aggregation. Tests for aggregation bias and errors of inference are conducted using indices previously tested for consistent aggregation. Failure to reject consistent aggregation in a partition did not ...

  1. DOES CONSISTENT AGGREGATION REALLY MATTER?

    OpenAIRE

    Shumway, C. Richard; Davis, George C.

    2000-01-01

    Consistent aggregation assures that behavioral properties, which apply to disaggregate relationships also, apply to aggregate relationships. The agricultural economics literature is reviewed which has tested for consistent aggregation or measured statistical bias and/or inferential errors due to aggregation. Tests for aggregation bias and errors of inference are conducted using indices previously tested for consistent aggregation. Failure to reject consistent aggregation in a partition did no...

  2. Spectral information as an orientation cue in dung beetles.

    Science.gov (United States)

    El Jundi, Basil; Foster, James J; Byrne, Marcus J; Baird, Emily; Dacke, Marie

    2015-11-01

    During the day, a non-uniform distribution of long and short wavelength light generates a colour gradient across the sky. This gradient could be used as a compass cue, particularly by animals such as dung beetles that rely primarily on celestial cues for orientation. Here, we tested if dung beetles can use spectral cues for orientation by presenting them with monochromatic (green and UV) light spots in an indoor arena. Beetles kept their original bearing when presented with a single light cue, green or UV, or when presented with both light cues set 180° apart. When either the UV or the green light was turned off after the beetles had set their bearing in the presence of both cues, they were still able to maintain their original bearing to the remaining light. However, if the beetles were presented with two identical green light spots set 180° apart, their ability to maintain their original bearing was impaired. In summary, our data show that ball-rolling beetles could potentially use the celestial chromatic gradient as a reference for orientation. PMID:26538537

  3. Comparison of lodgepole and jack pine resin chemistry: implications for range expansion by the mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae

    Directory of Open Access Journals (Sweden)

    Erin L. Clark

    2014-02-01

    Full Text Available The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC, where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle’s historic range (central BC to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC and one population of jack pine (AB were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels – a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle – were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the

  4. Intraguild predation and native lady beetle decline.

    Science.gov (United States)

    Gardiner, Mary M; O'Neal, Matthew E; Landis, Douglas A

    2011-01-01

    Coccinellid communities across North America have experienced significant changes in recent decades, with declines in several native species reported. One potential mechanism for these declines is interference competition via intraguild predation; specifically, increased predation of native coccinellid eggs and larvae following the introduction of exotic coccinellids. Our previous studies have shown that agricultural fields in Michigan support a higher diversity and abundance of exotic coccinellids than similar fields in Iowa, and that the landscape surrounding agricultural fields across the north central U.S. influences the abundance and activity of coccinellid species. The goal of this study was to quantify the amount of egg predation experienced by a native coccinellid within Michigan and Iowa soybean fields and explore the influence of local and large-scale landscape structure. Using the native lady beetle Coleomegilla maculata as a model, we found that sentinel egg masses were subject to intense predation within both Michigan and Iowa soybean fields, with 60.7% of egg masses attacked and 43.0% of available eggs consumed within 48 h. In Michigan, the exotic coccinellids Coccinella septempunctata and Harmonia axyridis were the most abundant predators found in soybean fields whereas in Iowa, native species including C. maculata, Hippodamia parenthesis and the soft-winged flower beetle Collops nigriceps dominated the predator community. Predator abundance was greater in soybean fields within diverse landscapes, yet variation in predator numbers did not influence the intensity of egg predation observed. In contrast, the strongest predictor of native coccinellid egg predation was the composition of edge habitats bordering specific fields. Field sites surrounded by semi-natural habitats including forests, restored prairies, old fields, and pasturelands experienced greater egg predation than fields surrounded by other croplands. This study shows that intraguild

  5. Intraguild predation and native lady beetle decline.

    Directory of Open Access Journals (Sweden)

    Mary M Gardiner

    Full Text Available Coccinellid communities across North America have experienced significant changes in recent decades, with declines in several native species reported. One potential mechanism for these declines is interference competition via intraguild predation; specifically, increased predation of native coccinellid eggs and larvae following the introduction of exotic coccinellids. Our previous studies have shown that agricultural fields in Michigan support a higher diversity and abundance of exotic coccinellids than similar fields in Iowa, and that the landscape surrounding agricultural fields across the north central U.S. influences the abundance and activity of coccinellid species. The goal of this study was to quantify the amount of egg predation experienced by a native coccinellid within Michigan and Iowa soybean fields and explore the influence of local and large-scale landscape structure. Using the native lady beetle Coleomegilla maculata as a model, we found that sentinel egg masses were subject to intense predation within both Michigan and Iowa soybean fields, with 60.7% of egg masses attacked and 43.0% of available eggs consumed within 48 h. In Michigan, the exotic coccinellids Coccinella septempunctata and Harmonia axyridis were the most abundant predators found in soybean fields whereas in Iowa, native species including C. maculata, Hippodamia parenthesis and the soft-winged flower beetle Collops nigriceps dominated the predator community. Predator abundance was greater in soybean fields within diverse landscapes, yet variation in predator numbers did not influence the intensity of egg predation observed. In contrast, the strongest predictor of native coccinellid egg predation was the composition of edge habitats bordering specific fields. Field sites surrounded by semi-natural habitats including forests, restored prairies, old fields, and pasturelands experienced greater egg predation than fields surrounded by other croplands. This study shows

  6. New records of predaceous diving beetles (Coleoptera:Dytiscidae) in Maine

    Science.gov (United States)

    Boobar, L.R.; Gibbs, K.E.; Longcore, J.R.; Perillo, A.M.

    1996-01-01

    Locations, habitat descriptions, and collection dates are listed for new records of 4 genera and 12 species of predaceous diving beetles (Coleoptera: Dytiscidae) in Maine. Previously, 17 genera and 53 species of the aquatic beetle were reported from Maine.

  7. Oviposition by small hive beetles elicits hygienic responses from Cape honeybees.

    Science.gov (United States)

    Ellis, J D; Richards, C S; Hepburn, H R; Elzen, P J

    2003-11-01

    Two novel behaviours, both adaptations of small hive beetles ( Aethina tumida Murray) and Cape honeybees ( Apis mellifera capensis Esch.), are described. Beetles puncture the sides of empty cells and oviposit under the pupae in adjoining cells. However, bees detect this ruse and remove infested brood (hygienic behaviour), even under such well-disguised conditions. Indeed, bees removed 91% of treatment brood (brood cells with punctured walls caused by beetles) but only 2% of control brood (brood not exposed to beetles). Only 91% of treatment brood actually contained beetle eggs; the data therefore suggest that bees remove only that brood containing beetle eggs and leave uninfected brood alone, even if beetles have accessed (but not oviposited on) the brood. Although this unique oviposition strategy by beetles appears both elusive and adaptive, Cape honeybees are able to detect and remove virtually all of the infested brood. PMID:14610654

  8. Charged Dust Aggregate Interactions

    Science.gov (United States)

    Matthews, Lorin; Hyde, Truell

    2015-11-01

    A proper understanding of the behavior of dust particle aggregates immersed in a complex plasma first requires a knowledge of the basic properties of the system. Among the most important of these are the net electrostatic charge and higher multipole moments on the dust aggregate as well as the manner in which the aggregate interacts with the local electrostatic fields. The formation of elongated, fractal-like aggregates levitating in the sheath electric field of a weakly ionized RF generated plasma discharge has recently been observed experimentally. The resulting data has shown that as aggregates approach one another, they can both accelerate and rotate. At equilibrium, aggregates are observed to levitate with regular spacing, rotating about their long axis aligned parallel to the sheath electric field. Since gas drag tends to slow any such rotation, energy must be constantly fed into the system in order to sustain it. A numerical model designed to analyze this motion provides both the electrostatic charge and higher multipole moments of the aggregate while including the forces due to thermophoresis, neutral gas drag, and the ion wakefield. This model will be used to investigate the ambient conditions leading to the observed interactions. This research is funded by NSF Grant 1414523.

  9. Aggregated Computational Toxicology Online Resource

    Data.gov (United States)

    U.S. Environmental Protection Agency — Aggregated Computational Toxicology Online Resource (AcTOR) is EPA's online aggregator of all the public sources of chemical toxicity data. ACToR aggregates data...

  10. Sexual contact influences orientation to plant attractant in Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

    Science.gov (United States)

    Chemical signals emitted by insects and their hosts are important for sexual communication and feeding. Plant volatiles facilitate the location of suitable hosts for feeding and oviposition, and may moderate responses to sex and aggregation pheromones. While mating has been shown to moderate behav...

  11. Distance and sex determine host plant choice by herbivorous beetles.

    Directory of Open Access Journals (Sweden)

    Daniel J Ballhorn

    Full Text Available BACKGROUND: Plants respond to herbivore damage with the release of volatile organic compounds (VOCs. This indirect defense can cause ecological costs when herbivores themselves use VOCs as cues to localize suitable host plants. Can VOCs reliably indicate food plant quality to herbivores? METHODOLOGY: We determined the choice behavior of herbivorous beetles (Chrysomelidae: Gynandrobrotica guerreroensis and Cerotoma ruficornis when facing lima bean plants (Fabaceae: Phaseolus lunatus with different cyanogenic potential, which is an important constitutive direct defense. Expression of inducible indirect defenses was experimentally manipulated by jasmonic acid treatment at different concentrations. The long-distance responses of male and female beetles to the resulting induced plant volatiles were investigated in olfactometer and free-flight experiments and compared to the short-distance decisions of the same beetles in feeding trials. CONCLUSION: Female beetles of both species were repelled by VOCs released from all induced plants independent of the level of induction. In contrast, male beetles were repelled by strongly induced plants, showed no significant differences in choice behavior towards moderately induced plants, but responded positively to VOCs released from little induced plants. Thus, beetle sex and plant VOCs had a significant effect on host searching behavior. By contrast, feeding behavior of both sexes was strongly determined by the cyanogenic potential of leaves, although females again responded more sensitively than males. Apparently, VOCs mainly provide information to these beetles that are not directly related to food quality. Being induced by herbivory and involved in indirect plant defense, such VOCs might indicate the presence of competitors and predators to herbivores. We conclude that plant quality as a food source and finding a potentially enemy-free space is more important for female than for male insect herbivores

  12. Rain forest provides pollinating beetles for atemoya crops.

    Science.gov (United States)

    Blanche, Rosalind; Cunningham, Saul A

    2005-08-01

    Small beetles, usually species of Nitidulidae, are the natural pollinators of atemoya (Annona squamosa L. x A. cherimola Mill. hybrids; custard apple) flowers but commercial atemoya growers often need to carry out labor-intensive hand pollination to produce enough high-quality fruit. Because Australian rain forest has plant species in the same family as atemoya (Annonaceae) and because many rain forest plants are beetle pollinated, we set out to discover whether tropical rain forest in far north Queensland harbors beetles that could provide this ecosystem service for atemoya crops. Orchards were chosen along a gradient of increasing distance from tropical rain forest (0.1-24 km). We sampled 100 flowers from each of nine atemoya orchards and determined the identity and abundance of insects within each flower. To assess the amount of pollination due to insects, we bagged six flowers per tree and left another six flowers per tree accessible to insects on 10 trees at an orchard near rain forest. Results indicated that atemoya orchards < or = 0.5 km from rain forest were predominantly visited by five previously unrecognized native beetle pollinators that are likely to originate in tropical rain forest. These native beetles occurred reliably enough in crops near rain forest to have a positive effect on the quantity of fruit produced but their contribution was not great enough to satisfy commercial production needs. Management changes, aimed at increasing native beetle abundance in crops, are required before these beetles could eliminate the need for growers to hand pollinate atemoya flowers. Appreciation of the value of this resource is necessary if we are to develop landscapes that both conserve native biodiversity and support agricultural production. PMID:16156571

  13. 7 CFR 301.48-6 - Movement of live Japanese beetles.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Movement of live Japanese beetles. 301.48-6 Section... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Japanese Beetle Quarantine and Regulations § 301.48-6 Movement of live Japanese beetles. Regulations requiring a permit for and...

  14. Visual explorer facilitator's guide

    CERN Document Server

    Palus, Charles J

    2010-01-01

    Grounded in research and practice, the Visual Explorer™ Facilitator's Guide provides a method for supporting collaborative, creative conversations about complex issues through the power of images. The guide is available as a component in the Visual Explorer Facilitator's Letter-sized Set, Visual Explorer Facilitator's Post card-sized Set, Visual Explorer Playing Card-sized Set, and is also available as a stand-alone title for purchase to assist multiple tool users in an organization.

  15. Protein Colloidal Aggregation Project

    Science.gov (United States)

    Oliva-Buisson, Yvette J. (Compiler)

    2014-01-01

    To investigate the pathways and kinetics of protein aggregation to allow accurate predictive modeling of the process and evaluation of potential inhibitors to prevalent diseases including cataract formation, chronic traumatic encephalopathy, Alzheimer's Disease, Parkinson's Disease and others.

  16. Platelet activation and aggregation

    DEFF Research Database (Denmark)

    Jensen, Maria Sander; Larsen, O H; Christiansen, Kirsten; Fenger-Eriksen, C; Ingerslev, J; Sørensen, Benny

    2013-01-01

    This study introduces a new laboratory model of whole blood platelet aggregation stimulated by endogenously generated thrombin, and explores this aspect in haemophilia A in which impaired thrombin generation is a major hallmark. The method was established to measure platelet aggregation initiated...... by tissue factor evaluated by means of impedance aggregometry. Citrated whole blood from healthy volunteers and haemophilia A patients with the addition of inhibitors of the contact pathway and fibrin polymerization was evaluated. In healthy persons, a second wave of platelet aggregation was found to...... coincide with the thrombin burst and to be abolished by thrombin inhibitors. In this system, platelet aggregation in severe haemophilia A (n = 10) was found to be significantly decreased as compared with healthy individuals (912 ± 294 vs. 1917 ± 793 AU × min, P = 0.003), most probably due to the weak level...

  17. Recycled aggregates concrete: aggregate and mix properties

    Directory of Open Access Journals (Sweden)

    González-Fonteboa, B.

    2005-09-01

    Full Text Available This study of structural concrete made with recycled concrete aggregate focuses on two issues: 1. The characterization of such aggregate on the Spanish market. This involved conducting standard tests to determine density, water absorption, grading, shape, flakiness and hardness. The results obtained show that, despite the considerable differences with respect to density and water absorption between these and natural aggregates, on the whole recycled aggregate is apt for use in concrete production. 2. Testing to determine the values of basic concrete properties: mix design parameters were established for structural concrete in non-aggressive environments. These parameters were used to produce conventional concrete, and then adjusted to manufacture recycled concrete aggregate (RCA concrete, in which 50% of the coarse aggregate was replaced by the recycled material. Tests were conducted to determine the physical (density of the fresh and hardened material, water absorption and mechanical (compressive strength, splitting tensile strength and modulus of elasticity properties. The results showed that, from the standpoint of its physical and mechanical properties, concrete in which RCA accounted for 50% of the coarse aggregate compared favourably to conventional concrete.

    Se aborda el estudio de hormigones estructurales fabricados con áridos reciclados procedentes de hormigón, incidiéndose en dos aspectos: 1. Caracterización de tales áridos, procedentes del mercado español. Para ello se llevan a cabo ensayos de densidad, absorción, granulometría, coeficiente de forma, índice de lajas y dureza. Los resultados obtenidos han puesto de manifiesto que, a pesar de que existen diferencias notables (sobre todo en cuanto a densidad y absorción con los áridos naturales, las características de los áridos hacen posible la fabricación de hormigones. 2. Ensayos sobre propiedades básicas de los hormigones: se establecen parámetros de dosificaci

  18. Rapid Divergence of Nesting Depth and Digging Appendages among Tunneling Dung Beetle Populations and Species.

    Science.gov (United States)

    Macagno, Anna L M; Moczek, Armin P; Pizzo, Astrid

    2016-05-01

    Many dung beetle communities are characterized by species that share very similar morphological, ecological, and behavioral traits and requirements yet appear to be stably maintained. Here, we document that the morphologically nearly indistinguishable, sympatric, and syntopic tunneling sister species Onthophagus taurus and Onthophagus illyricus may be avoiding competitive exclusion by nesting at remarkably different soil depths. Intriguingly, we also find rapid divergence in preferred nesting depth across native and recently established O. taurus populations. Furthermore, geometric morphometric analyses reveal that both inter- and intraspecific divergences in nesting depth are paralleled by similar changes in the shape of the primary digging appendages, the fore tibiae. Collectively, our results identify preferred nesting depth and tibial shape as surprisingly evolutionarily labile and with the potential to ease interspecific competition and/or to facilitate adaptation to local climatic conditions. PMID:27105002

  19. Coagulation with limited aggregations

    CERN Document Server

    Bertoin, Jean

    2012-01-01

    Smoluchowski's coagulation equations can be used as elementary mathematical models for the formation of polymers. We review here some recent contributions on a variation of this model in which the number of aggregations for each atom is a priori limited. Macroscopic results in the deterministic setting can be explained at the microscopic level by considering a version of stochastic coalescence with limited aggregations, which can be related to the so-called random configuration model of random graph theory.

  20. The Aggregation Dilemma

    OpenAIRE

    Ingmar Schumacher

    2014-01-01

    The results in this paper show that the level of aggregation used in a social welfare func- tion matters significantly for policy analysis. Using climate change as an example, it is shown that, under the mild and widely-accepted assumptions of asymmetric climate change impacts and declining marginal utility, an aggregation dilemma may arise that dwarfs most other policy-relevant aspects in the climate change cost-benefit analysis. Estimates based on the RICE-99 model (Nordhaus and Boyer 2000)...

  1. Glycine reduces platelet aggregation

    OpenAIRE

    Schemmer, Peter; Zhong, Zhi; Galli, Uwe; Wheeler, Michael D.; Xiangli, Li; Bradford, Blair U.; Conzelmann, Lars O.; Forman, Dow; Boyer, José; Thurman, Ronald G

    2012-01-01

    It has been demonstrated that a wide variety of white blood cells and macrophages (i.e. Kupffer cells, alveolar and peritoneal macrophages and neutrophils) contain glycine-gated chloride channels. Binding of glycine on the receptor stimulates Cl− influx causing membrane hyperpolarization that prevents agonist-induced influx of calcium. Since platelet-aggregation is calcium-dependent, this study was designed to test the hypothesis that glycine would inhibit platelet aggregation. Rats were fed ...

  2. Flow Visualization of Rhinoceros Beetle (Trypoxylus dichotomus) in Free Flight

    Institute of Scientific and Technical Information of China (English)

    Tien Van Truong; Tuyen Quang Le; Hieu Trung Tran; Hoon Cheol Park; Kwang Joon Yoon; Doyoung Byun

    2012-01-01

    Aerodynamic characteristics of the beetle,Trypoxylus dichotomus,which has a pair of elytra (forewings) and flexible hind wings,are investigated.Visualization experiments were conducted for various flight conditions of a beetle,Trypoxylus dichotomus:free,tethered,hovering,forward and climbing flights.Leading edge,trailing edge and tip vortices on both wings were observed clearly.The leading edge vortex was stable and remained on the top surface of the elytron for a wide interval during the downstroke of free forward flight.Hence,the elytron may have a considerable role in lift force generation of the beetle.In addition,we reveal a suction phenomenon between the gaps of the hind wing and the elytron in upstroke that may improve the positive lift force on the hind wing.We also found the reverse clap-fling mechanism of the T.dichotomus beetle in hovering flight.The hind wings touch together at the beginning of the upstroke.The vortex generation,shedding and interaction give a better understanding of the detailed aerodynamic mechanism of beetle flight.

  3. Origin and Diversification of Dung Beetles in Madagascar

    Directory of Open Access Journals (Sweden)

    Andreia Miraldo

    2011-04-01

    Full Text Available Madagascar has a rich fauna of dung beetles (Scarabaeinae and Aphodiinae withalmost 300 species described to date. Like most other taxa in Madagascar, dung beetles exhibit an exceptionally high level of endemism (96% of the species. Here,we review the current knowledge of the origin and diversification of Malagasy dung beetles. Based on molecular phylogenies, the extant dung beetles originate from eight colonizations, of which four have given rise to extensive radiations. These radiations have occurred in wet forests, while the few extant species in the less successfulradiations occur in open and semi-open habitats. We discuss the likely mechanisms of speciation and the ecological characteristics of the extant communities, emphasizing the role of adaptation along environmental gradients and allopatric speciation in generating the exceptionally high beta diversity in Malagasy dung beetles. Phylogeographic analyses of selected species reveal complex patterns with evidence for genetic introgression between old taxa. The introduction of cattle to Madagascar 1500 years ago created a new abundant resource, onto which a few species haveshifted and thereby been able to greatly expand their geographical ranges.

  4. Origin and Diversification of Dung Beetles in Madagascar.

    Science.gov (United States)

    Miraldo, Andreia; Wirta, Helena; Hanski, Ilkka

    2011-01-01

    Madagascar has a rich fauna of dung beetles (Scarabaeinae and Aphodiinae) withalmost 300 species described to date. Like most other taxa in Madagascar, dung beetles exhibit an exceptionally high level of endemism (96% of the species). Here,we review the current knowledge of the origin and diversification of Malagasy dung beetles. Based on molecular phylogenies, the extant dung beetles originate from eight colonizations, of which four have given rise to extensive radiations. These radiations have occurred in wet forests, while the few extant species in the less successfulradiations occur in open and semi-open habitats. We discuss the likely mechanisms of speciation and the ecological characteristics of the extant communities, emphasizing the role of adaptation along environmental gradients and allopatric speciation in generating the exceptionally high beta diversity in Malagasy dung beetles. Phylogeographic analyses of selected species reveal complex patterns with evidence for genetic introgression between old taxa. The introduction of cattle to Madagascar 1500 years ago created a new abundant resource, onto which a few species haveshifted and thereby been able to greatly expand their geographical ranges. PMID:26467617

  5. Training facilitators and supervisors

    DEFF Research Database (Denmark)

    Kjær, Louise Binow; O Connor, Maja; Krogh, Kristian;

    At the Master’s program in Medicine at Aarhus University, Denmark, we have developed a faculty development program for facilitators and supervisors in 4 progressing student modules in communication, cooperation, and leadership. 1) A course for module 1 and 3 facilitators inspired by the apprentic...

  6. Fatty Acid Composition of Novel Host Jack Pine Do Not Prevent Host Acceptance and Colonization by the Invasive Mountain Pine Beetle and Its Symbiotic Fungus.

    Science.gov (United States)

    Ishangulyyeva, Guncha; Najar, Ahmed; Curtis, Jonathan M; Erbilgin, Nadir

    2016-01-01

    Fatty acids are major components of plant lipids and can affect growth and development of insect herbivores. Despite a large literature examining the roles of fatty acids in conifers, relatively few studies have tested the effects of fatty acids on insect herbivores and their microbial symbionts. Particularly, whether fatty acids can affect the suitability of conifers for insect herbivores has never been studied before. Thus, we evaluated if composition of fatty acids impede or facilitate colonization of jack pine (Pinus banksiana) by the invasive mountain pine beetle (Dendroctonus ponderosae) and its symbiotic fungus (Grosmannia clavigera). This is the first study to examine the effects of tree fatty acids on any bark beetle species and its symbiotic fungus. In a novel bioassay, we found that plant tissues (hosts and non-host) amended with synthetic fatty acids at concentrations representative of jack pine were compatible with beetle larvae. Likewise, G. clavigera grew in media amended with lipid fractions or synthetic fatty acids at concentrations present in jack pine. In contrast, fatty acids and lipid composition of a non-host were not suitable for the beetle larvae or the fungus. Apparently, concentrations of individual, rather than total, fatty acids determined the suitability of jack pine. Furthermore, sampling of host and non-host tree species across Canada demonstrated that the composition of jack pine fatty acids was similar to the different populations of beetle's historical hosts. These results demonstrate that fatty acids composition compatible with insect herbivores and their microbial symbionts can be important factor defining host suitability to invasive insects. PMID:27583820

  7. Hold your breath beetle-Mites!

    Science.gov (United States)

    Gudowska, Agnieszka; Drobniak, Szymon M; Schramm, Bartosz W; Labecka, Anna Maria; Kozlowski, Jan; Bauchinger, Ulf

    2016-01-01

    Respiratory gas exchange in insects occurs via a branching tracheal system. The entrances to the air-filled tracheae are the spiracles, which are gate-like structures in the exoskeleton. The open or closed state of spiracles defines the three possible gas exchange patterns of insects. In resting insects, spiracles may open and close over time in a repeatable fashion that results in a discontinuous gas exchange (DGE) pattern characterized by periods of zero organism-to-environment gas exchange. Several adaptive hypotheses have been proposed to explain why insects engage in DGE, but none have attracted overwhelming support. We provide support for a previously untested hypothesis that posits that DGE minimizes the risk of infestation of the tracheal system by mites and other agents. Here, we analyze the respiratory patterns of 15 species of ground beetle (Carabidae), of which more than 40% of individuals harbored external mites. Compared with mite-free individuals, infested one's engaged significantly more often in DGE. Mite-free individuals predominantly employed a cyclic or continuous gas exchange pattern, which did not include complete spiracle closure. Complete spiracle closure may prevent parasites from invading, clogging, or transferring pathogens to the tracheal system or from foraging on tissue not protected by thick chitinous layers. PMID:26689423

  8. Marking small hive beetles with thoracic notching: effects on longevity, flight ability and fecundity

    OpenAIRE

    De Guzman, Lilia; Frake, Amanda; Rinderer, Thomas

    2012-01-01

    International audience We tested two marking techniques for adult small hive beetles (SHB): dusting and thoracic notching. The use of blue and red chalk dusts to mark beetles was not persistent and caused early death of SHB with an average survival of 52.6 ± 23.8 and 13.9 ± 7.3 days, respectively. In contrast, notched beetles survived longer (mean = 353.6 ± 5.3 days) with the last beetle dying after 383 days. Likewise, notched beetles (presumed to be injured because of oozing hemolymph fro...

  9. Changes in food resources and conservation of scarab beetles

    DEFF Research Database (Denmark)

    Carpaneto, Giuseppe Maria; Mazziotta, Adriano; Piattella, Emanuele

    2005-01-01

    The aim of the research was to show how a change in land use influences the structure of a dung beetle assemblage and affect its conservation. In the Pineto Urban Regional Park (Rome), dog dung is the sole food resource currently available for scarab dung beetles, after the recent removal of wild...... and domestic herbivores. A one-year sampling was conducted to study the scarab assemblage in dog scats (1999) and to compare it with the previous assemblage associated with sheep droppings (1986). Richness, evenness and similarity parameters were compared between the two allochronic assemblages. From...... sheep to dog dung, an impoverishment of the total richness was observed (from 19 to 9 species) together with an increase of individuals (by 7 times). Dog dung harboured 20% of the current scarab dung beetle fauna of Rome, probably as a consequence of the dog mixed diet, rich in cellulose. Both the...

  10. Micro-structure and frictional characteristics of beetle's joint

    Institute of Scientific and Technical Information of China (English)

    DAI Zhendong; Stanislav N. Gorb

    2004-01-01

    Geometric and micro-structure design, tribology properties of beetle joints were experimentally studied, which aimed to enlighten ideas for the joint design of MEMS.The observation by using SEM and microscopy suggested that beetle's joints consist of a concave surface matched with a convex surface. The heads of the beetles, rubbing with flat glass, were tested in fresh and dried statuses and compared with sapphire ball with flat glass. Frictional coefficient of the joint material on glass was significantly lower than that of the sapphire sphere on glass. The material of the joint cuticle for convex surface is rather stiff (the elastic modulus 4.5 Gpa) and smooth. The surface is hydrophobic (the contact angle of distilled water was 88.3° ). It is suggested here that the high stiffness of the joint material and hydrophobicity of the joint surface are parts of the mechanism minimizing friction in insect joints.

  11. The alternative Pharaoh approach: stingless bees mummify beetle parasites alive

    Science.gov (United States)

    Greco, Mark K.; Hoffmann, Dorothee; Dollin, Anne; Duncan, Michael; Spooner-Hart, Robert; Neumann, Peter

    2010-03-01

    Workers from social insect colonies use different defence strategies to combat invaders. Nevertheless, some parasitic species are able to bypass colony defences. In particular, some beetle nest invaders cannot be killed or removed by workers of social bees, thus creating the need for alternative social defence strategies to ensure colony survival. Here we show, using diagnostic radioentomology, that stingless bee workers ( Trigona carbonaria) immediately mummify invading adult small hive beetles ( Aethina tumida) alive by coating them with a mixture of resin, wax and mud, thereby preventing severe damage to the colony. In sharp contrast to the responses of honeybee and bumblebee colonies, the rapid live mummification strategy of T. carbonaria effectively prevents beetle advancements and removes their ability to reproduce. The convergent evolution of mummification in stingless bees and encapsulation in honeybees is another striking example of co-evolution between insect societies and their parasites.

  12. Bird and beetle assemblages in mountain pine beetle killed forests and those subsequently burned: evidence for an effect of compound natural disturbances in British Columbia

    OpenAIRE

    House, Kimberly Nicole

    2014-01-01

    The recent mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins) outbreak in British Columbia (BC) is unprecedented in severity and extent, and has created a landscape of beetle-killed trees through which wildfires are now burning as compound natural disturbances. We asked the question: Is there an impact of grey phase MPB kill severity on bird and beetle assemblages, and does an effect persist following wildfire in BC? We compared the bird community of central interior BC against categ...

  13. Evaluating leaf litter beetle data sampled by Winkler extraction from Atlantic forest sites in southern Brazil

    Directory of Open Access Journals (Sweden)

    Philipp Werner Hopp

    2011-06-01

    Full Text Available Evaluating leaf litter beetle data sampled by Winkler extraction from Atlantic forest sites in southern Brazil. To evaluate the reliability of data obtained by Winkler extraction in Atlantic forest sites in southern Brazil, we studied litter beetle assemblages in secondary forests (5 to 55 years after abandonment and old-growth forests at two seasonally different points in time. For all regeneration stages, species density and abundance were lower in April compared to August; but, assemblage composition of the corresponding forest stages was similar in both months. We suggest that sampling of small litter inhabiting beetles at different points in time using the Winkler technique reveals identical ecological patterns, which are more likely to be influenced by sample incompleteness than by differences in their assemblage composition. A strong relationship between litter quantity and beetle occurrences indicates the importance of this variable for the temporal species density pattern. Additionally, the sampled beetle material was compared with beetle data obtained with pitfall traps in one old-growth forest. Over 60% of the focal species captured with pitfall traps were also sampled by Winkler extraction in different forest stages. Few beetles with a body size too large to be sampled by Winkler extraction were only sampled with pitfall traps. This indicates that the local litter beetle fauna is dominated by small species. Hence, being aware of the exclusion of large beetles and beetle species occurring during the wet season, the Winkler method reveals a reliable picture of the local leaf litter beetle community.

  14. Fungi associated with the beetles of Ips typographus on Norway spruce in southern Poland

    Directory of Open Access Journals (Sweden)

    Robert Jankowiak

    2014-08-01

    Full Text Available The mycobiota of the beetles of the phloem-feeding spruce bark beetle, Ips typographus was studied. The most important group of fungi were the ophiostomatoid fungi. Among them O. penicillatum was very frequent ophiostomatoid species. Other common fungi were O. ainoae, O. bicolor, O. piceaperdum and O. piceae. The ophiostomatoid fungi were often more frequent in beetles collected in galleries than in the beetles caught With a trap. Generally the ophiostomatoid fungi were more ofien isolated from the beetle.s bathed in sterile water for 30 seconds. However C. polonica, O. ainoae, and O. minutum occurred most abundantly in the beetles disinfected in 96% ethyl alcohol for 15 and 30 seconds.

  15. Sustainable Concrete with Recycled Aggregate

    OpenAIRE

    Kara, P

    2012-01-01

    Concretes produced with recycled aggregates are the subject of several papers recently published in the technical literature. Substitution of natural aggregates can be one of possibilities to take care of landfills and increase of CO2 emissions into the atmosphere in Latvia. Recycled aggregate is a valuable resource; value-added consumption of recycled aggregate, as replacement for virgin aggregate in concrete, can yield significant energy and environmental benefits. In present study recycled...

  16. Arrow's Theorem in Judgement Aggregation

    OpenAIRE

    Franz Dietrich; Christian List

    2005-01-01

    In response to recent work on the aggregation of individual judgements on logically connected propositions into collective judgements, it is often asked whether judgement aggregation is a special case of Arrowian preference aggregation. We argue the opposite. After proving a general impossibility theorem, we construct an embedding of preference aggregation into judgement aggregation and prove Arrow's theorem as a corollary of our result. Although we provide a new proof of Arrow's theorem, our...

  17. Absorption Spectra of Astaxanthin Aggregates

    OpenAIRE

    Olsina, Jan; Durchan, Milan; Minofar, Babak; Polivka, Tomas; Mancal, Tomas

    2012-01-01

    Carotenoids in hydrated polar solvents form aggregates characterized by dramatic changes in their absorption spectra with respect to monomers. Here we analyze absorption spectra of aggregates of the carotenoid astaxanthin in hydrated dimethylsulfoxide. Depending on water content, two types of aggregates were produced: H-aggregates with absorption maximum around 390 nm, and J-aggregates with red-shifted absorption band peaking at wavelengths >550 nm. The large shifts with respect to absorption...

  18. Aggregate Oligopoly Games with Entry

    OpenAIRE

    Anderson, Simon P.; Erkal, Nisvan; Piccinin, Daniel

    2013-01-01

    We use cumulative reaction functions to compare long-run market structures in aggregative oligopoly games. We first compile an IO toolkit for aggregative games. We show strong neutrality properties across market structures. The aggregator stays the same, despite changes in the number of firms and their actions. The IIA property of demands (CES and logit) implies that consumer surplus depends on the aggregator alone, and that the Bertrand pricing game is aggregative. We link together the follo...

  19. Photochemical oxidant injury and bark beetle coleoptera scolytidae infestation of ponderosa pine. I. Incidence of bark beetle infestation in injured trees

    Energy Technology Data Exchange (ETDEWEB)

    Stark, R.W.; Miller, P.R.; Cobb, F.W. Jr.; Wood, D.L.; Parmeter, J.R. Jr.

    1968-05-01

    A total of 107 beetle-killed and 963 nearest-neighbor ponderosa pines were examined to determine the association between severity of atmospheric pollution injury and infestation by bark beetles. Trees exhibiting advanced symptoms of pollution injury were most frequently infested by the western pine beetle, Dendroctonus brevicomis, and the mountain pine beetle, D. ponderosae. The degree of injury and incidence of bark beetle infestation were not related to total height, diameter, length of live and dead crown or crown class. As severity of oxidant injury increased, live crown ratio decreased and incidence of bark beetle infestation increased. One hundred noninfested trees in each of three disease categories, advanced, intermediate, and healthy, were examined for evidence of prior beetle attacks. Thirty-six percent of the advanced-diseased trees versus only 5% of the healthy trees were attacked. Thus, the beetles may discriminate between healthy and diseased trees at a distance, upon contact with the host, or both. These studies indicate strongly that atmospheric pollution injury predisposes ponderosa pine to bark beetle infestations. 3 references, 7 tables.

  20. Facilitation of CRISPR adaptation

    OpenAIRE

    Abedon, Stephen T.

    2011-01-01

    CRISPR systems, as bacterial defenses against phages, logically must display in their functioning a sequence of at least three major steps. These, in order of occurrence, are “facilitation,” adaptation and interference, where the facilitation step is the main issue considered in this commentary. Interference is the blocking of phage infections as mediated in part by CRISPR spacer sequences. Adaptation, at least as narrowly defined, is the acquisition of these spacer sequences by CRISPR loci. ...

  1. Facilitating Knowledge Sharing

    DEFF Research Database (Denmark)

    Holdt Christensen, Peter

    Abstract This paper argues that knowledge sharing can be conceptualized as different situations of exchange in which individuals relate to each other in different ways, involving different rules, norms and traditions of reciprocity regulating the exchange. The main challenge for facilitating...... and the intermediaries regulating the exchange, and facilitating knowledge sharing should therefore be viewed as a continuum of practices under the influence of opportunistic behaviour, obedience or organizational citizenship behaviour. Keywords: Knowledge sharing, motivation, organizational settings, situations...

  2. Aggregation on heterogeneous surface

    Institute of Scientific and Technical Information of China (English)

    Lu Hang-Jun; Wu Feng-Min; Fang Yun-Zhang

    2004-01-01

    Chessboard-like substrates are introduced in this paper, in order to study the diffusion-limited aggregation (DLA)and the motion of poly-atoms on heterogeneous surfaces. The effect of morphology of such substrates upon the cluster aggregation is investigated using the Monte Carlo simulation. It is found that the growth process and the cluster morphology are governed by the energetic topography of the substrates. Our simulation also indicate that the island density and the fractal dimension of the clusters depend strongly on the substrate topography and the activation energy.

  3. Spruce Beetle Biology, Ecology and Management in the Rocky Mountains: An Addendum to Spruce Beetle in the Rockies

    OpenAIRE

    Jenkins, Michael J; Hebertson, Elizabeth G; A. Steven Munson

    2014-01-01

    Spruce beetle outbreaks have been reported in the Rocky Mountains of western North America since the late 1800s. In their classic paper, Spruce Beetle in the Rockies, Schmid and Frye reviewed the literature that emerged from the extensive outbreaks in Colorado in the 1940s. A new wave of outbreaks has affected Rocky Mountain subalpine spruce-fir forests beginning in the mid-1980s and continuing to the present. These outbreaks have spurred another surge of basic and applied research in the bio...

  4. Aggregates, broccoli and cauliflower

    Science.gov (United States)

    Grey, Francois; Kjems, Jørgen K.

    1989-09-01

    Naturally grown structures with fractal characters like broccoli and cauliflower are discussed and compared with DLA-type aggregates. It is suggested that the branching density can be used to characterize the growth process and an experimental method to determine this parameter is proposed.

  5. Diffusion in aggregated soil.

    NARCIS (Netherlands)

    Rappoldt, C.

    1992-01-01

    The structure of an aggregated soil is characterized by the distribution of the distance from an arbitrary point in the soil to the nearest macropore or crack. From this distribution an equivalent model system is derived to which a diffusion model can be more easily applied. The model system consist

  6. The redbay ambrosia beetle, Xyleborus glabratus: A threat to avocado

    Science.gov (United States)

    Laurel wilt (LW) is a disease caused by Raffaelea sp., a fungal symbiont associated with the recently-introduced redbay ambrosia beetle (RAB), Xyleborus glabratus. Impact of RAB as a vector of the disease to avocado is a threat to avocado production in the U.S. Since 2006, we have a) tested suscepti...

  7. Use of infochemicals to attract carrion beetles into pitfall traps

    Czech Academy of Sciences Publication Activity Database

    Podskalská, H.; Růžička, J.; Hoskovec, Michal; Šálek, M.

    2009-01-01

    Roč. 132, č. 1 (2009), s. 59-64. ISSN 0013-8703 Institutional research plan: CEZ:AV0Z40550506 Keywords : burying beetles * dimethylsulfide * dimethyldisulfide * dimethyltrisulfide Subject RIV: CC - Organic Chemistry Impact factor: 1.568, year: 2009

  8. Surveying an endangered saproxylic beetle, Osmoderma eremita, in Mediterranean woodlands

    DEFF Research Database (Denmark)

    Chiari, Stefano; Zauli, Agnese; Mazziotta, Adriano; Luiselli, Luca; Audisio, Paolo; Carpaneto, Giuseppe M.

    2013-01-01

    . Detection probability and population size estimates were drawn from each of these four capture methods. There were strong differences in detection probability among methods. Despite using pheromone and beetle manipulation, capture histories were not affected by trap-happiness or trap-shyness. Population...

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

    Directory of Open Access Journals (Sweden)

    Andrea Di Giulio

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

  10. PATCH EXPLOITATION BY FEMALE RED FLOUR BEETLES, TRIBOLIUM CASTANEUM

    Science.gov (United States)

    The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera:Tenebrionidae) has had a long association with human stored food and can be a major pest in anthropogenic structures used for the processing and storage of grain-based products. Anthropogenic structures are fragmented landscapes characte...

  11. CUTICULAR HYDROCARBONS OF THE SUNFLOWER BEETLE, ZYGOGRAMMA EXCLAMATIONIS

    Science.gov (United States)

    Hydrocarbons were the major lipid class on the cuticular surface of adults, nymphs, and eggs of the sunflower beetle, Zygogramma exclamationis, characterized by gas chromatography-mass spectrometry. Minor amounts of wax ester from 40 to 48 carbon atoms in size were only detected in larvae. The hyd...

  12. The genome of the model beetle and pest Tribolium castaneum

    DEFF Research Database (Denmark)

    Denell, Robin; Gibbs, Richard; Muzny, Donna;

    2008-01-01

    Tribolium castaneum is a member of the most species-rich eukaryotic order, a powerful model organism for the study of generalized insect development, and an important pest of stored agricultural products. We describe its genome sequence here. This omnivorous beetle has evolved the ability to inte...

  13. Origin and Diversification of Dung Beetles in Madagascar

    DEFF Research Database (Denmark)

    Miraldo, Andreia; Wirta, Helena; Hanski, Ilkka

    2011-01-01

    and semi-open habitats. We discuss the likely mechanisms of speciation and the ecological characteristics of the extant communities, emphasizing the role of adaptation along environmental gradients and allopatric speciation in generating the exceptionally high beta diversity in Malagasy dung beetles...

  14. Spatio-Temporal Distribution of Bark and Ambrosia Beetles in a Brazilian Tropical Dry Forest.

    Science.gov (United States)

    Macedo-Reis, Luiz Eduardo; Novais, Samuel Matos Antunes de; Monteiro, Graziela França; Flechtmann, Carlos Alberto Hector; Faria, Maurício Lopes de; Neves, Frederico de Siqueira

    2016-01-01

    Bark and the ambrosia beetles dig into host plants and live most of their lives in concealed tunnels. We assessed beetle community dynamics in tropical dry forest sites in early, intermediate, and late successional stages, evaluating the influence of resource availability and seasonal variations in guild structure. We collected a total of 763 beetles from 23 species, including 14 bark beetle species, and 9 ambrosia beetle species. Local richness of bark and ambrosia beetles was estimated at 31 species. Bark and ambrosia composition was similar over the successional stages gradient, and beta diversity among sites was primarily determined by species turnover, mainly in the bark beetle community. Bark beetle richness and abundance were higher at intermediate stages; availability of wood was the main spatial mechanism. Climate factors were effectively non-seasonal. Ambrosia beetles were not influenced by successional stages, however the increase in wood resulted in increased abundance. We found higher richness at the end of the dry and wet seasons, and abundance increased with air moisture and decreased with higher temperatures and greater rainfall. In summary, bark beetle species accumulation was higher at sites with better wood production, while the needs of fungi (host and air moisture), resulted in a favorable conditions for species accumulation of ambrosia. The overall biological pattern among guilds differed from tropical rain forests, showing patterns similar to dry forest areas. PMID:27271969

  15. Fire severity unaffected by spruce beetle outbreak in spruce-fir forests in southwestern Colorado.

    Science.gov (United States)

    Andrus, Robert A; Veblen, Thomas T; Harvey, Brian J; Hart, Sarah J

    2016-04-01

    Recent large and severe outbreaks of native bark beetles have raised concern among the general public and land managers about potential for amplified fire activity in western North America. To date, the majority of studies examining bark beetle outbreaks and subsequent fire severity in the U.S. Rocky Mountains have focused on outbreaks of mountain pine beetle (MPB; Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests, but few studies, particularly field studies, have addressed the effects of the severity of spruce beetle (Dendroctonus rufipennis Kirby) infestation on subsequent fire severity in subalpine Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) forests. In Colorado, the annual area infested by spruce beetle outbreaks is rapidly rising, while MPB outbreaks are subsiding; therefore understanding this relationship is of growing importance. We collected extensive field data in subalpine forests in the eastern San Juan Mountains, southwestern Colorado, USA, to investigate whether a gray-stage (fire) spruce beetle infestation affected fire severity. Contrary to the expectation that bark beetle infestation alters subsequent fire severity, correlation and multivariate generalized linear regression analysis revealed no influence of pre-fire spruce beetle severity on nearly all field or remotely sensed measurements of fire severity. Findings were consistent across moderate and extreme burning conditions. In comparison to severity of the pre-fire beetle outbreak, we found that topography, pre-outbreak basal area, and weather conditions exerted a stronger effect on fire severity. Our finding that beetle infestation did not alter fire severity is consistent with previous retrospective studies examining fire activity following other bark beetle outbreaks and reiterates the overriding influence of climate that creates conditions conducive to large, high-severity fires in the subalpine zone of Colorado. Both bark beetle outbreaks and

  16. Juvenile hormone regulates extreme mandible growth in male stag beetles.

    Science.gov (United States)

    Gotoh, Hiroki; Cornette, Richard; Koshikawa, Shigeyuki; Okada, Yasukazu; Lavine, Laura Corley; Emlen, Douglas J; Miura, Toru

    2011-01-01

    The morphological diversity of insects is one of the most striking phenomena in biology. Evolutionary modifications to the relative sizes of body parts, including the evolution of traits with exaggerated proportions, are responsible for a vast range of body forms. Remarkable examples of an insect trait with exaggerated proportions are the mandibular weapons of stag beetles. Male stag beetles possess extremely enlarged mandibles which they use in combat with rival males over females. As with other sexually selected traits, stag beetle mandibles vary widely in size among males, and this variable growth results from differential larval nutrition. However, the mechanisms responsible for coupling nutrition with growth of stag beetle mandibles (or indeed any insect structure) remain largely unknown. Here, we demonstrate that during the development of male stag beetles (Cyclommatus metallifer), juvenile hormone (JH) titers are correlated with the extreme growth of an exaggerated weapon of sexual selection. We then investigate the putative role of JH in the development of the nutritionally-dependent, phenotypically plastic mandibles, by increasing hemolymph titers of JH with application of the JH analog fenoxycarb during larval and prepupal developmental periods. Increased JH signaling during the early prepupal period increased the proportional size of body parts, and this was especially pronounced in male mandibles, enhancing the exaggerated size of this trait. The direction of this response is consistent with the measured JH titers during this same period. Combined, our results support a role for JH in the nutrition-dependent regulation of extreme mandible growth in this species. In addition, they illuminate mechanisms underlying the evolution of trait proportion, the most salient feature of the evolutionary diversification of the insects. PMID:21731659

  17. Juvenile hormone regulates extreme mandible growth in male stag beetles.

    Directory of Open Access Journals (Sweden)

    Hiroki Gotoh

    Full Text Available The morphological diversity of insects is one of the most striking phenomena in biology. Evolutionary modifications to the relative sizes of body parts, including the evolution of traits with exaggerated proportions, are responsible for a vast range of body forms. Remarkable examples of an insect trait with exaggerated proportions are the mandibular weapons of stag beetles. Male stag beetles possess extremely enlarged mandibles which they use in combat with rival males over females. As with other sexually selected traits, stag beetle mandibles vary widely in size among males, and this variable growth results from differential larval nutrition. However, the mechanisms responsible for coupling nutrition with growth of stag beetle mandibles (or indeed any insect structure remain largely unknown. Here, we demonstrate that during the development of male stag beetles (Cyclommatus metallifer, juvenile hormone (JH titers are correlated with the extreme growth of an exaggerated weapon of sexual selection. We then investigate the putative role of JH in the development of the nutritionally-dependent, phenotypically plastic mandibles, by increasing hemolymph titers of JH with application of the JH analog fenoxycarb during larval and prepupal developmental periods. Increased JH signaling during the early prepupal period increased the proportional size of body parts, and this was especially pronounced in male mandibles, enhancing the exaggerated size of this trait. The direction of this response is consistent with the measured JH titers during this same period. Combined, our results support a role for JH in the nutrition-dependent regulation of extreme mandible growth in this species. In addition, they illuminate mechanisms underlying the evolution of trait proportion, the most salient feature of the evolutionary diversification of the insects.

  18. Polarizing properties and structural characteristics of the cuticle of the scarab Beetle Chrysina gloriosa

    International Nuclear Information System (INIS)

    The scarab beetle Chrysina gloriosa is green with gold-colored stripes along its elytras. The properties of light reflected on these areas are investigated using Mueller-matrix spectroscopic ellipsometry. Both areas reflect light with high degree of left-handed polarization but this effect occurs for specular reflection for the gold-colored areas and for off-specular angles for the green areas. The colors and polarization phenomena originate from reflection of light in the cuticle and a structural analysis is presented to facilitate understanding of the different behaviors of these two areas. Scanning electron microscopy (SEM) images of the cross section of beetle cuticles show a multilayered structure. On the gold-colored areas the layers are parallel to the surface whereas on the green-colored areas they form cusp-like structures. Optical microscopy images show a rather flat surface in the gold-colored areas compared to the green-colored areas which display a net of polygonal cells with star-shaped cavities in the center. Each of the polygons corresponds to one of the cusps observed in the SEM images. Atomic force microscopy images of the star-shaped cavities are also provided. The roughness of the surface and the cusp-like structure of the green-colored areas are considered to cause scattering on this area. - Highlights: • Chrysina gloriosa reflects light with high degree of left-handed polarization. • Gold-colored areas are good specular reflectors whereas green-colored areas scatter light. • The cusp-like structure in the green areas is responsible for the scattering

  19. Competitive release leads to range expansion and rampant speciation in malagasy dung beetles.

    Science.gov (United States)

    Miraldo, Andreia; Hanski, Ilkka A

    2014-07-01

    Competition is often thought to promote ecological diversification and thereby to facilitate the coexistence of competitors during evolutionary radiations. At large spatial scales, species may also coexist by having allopatric distributions, which raises the question about the role of range expansion in the proliferation of species during radiations. Here, we integrate a well-sampled (50 out of 74 species) and timed phylogeny of Nanos and Apotolamprus dung beetles (Canthonini) in Madagascar with data on species' geographical ranges, abundances, and body sizes. There is an overall decline in lineage accumulation through time since the colonization of northern Madagascar in the mid Miocene (24-13 Ma). A clade of 24 extant Nanos species (clade L) originating 6.0 Ma exhibits an increase in speciation rate, which is associated with a significant increase in body size and strikingly allopatric distributions of the species. Large body size typically confers a competitive advantage in dung beetles, which is here reflected by strong numerical dominance of clade L species in local communities. We suggest that the "key innovation" of large body size has allowed range expansion due to competitive release, which has created extensive opportunities for allopatric speciation and differentiation along environmental gradients. Most theories to explain diversification patterns in Madagascar rely on allopatric modes of speciation, but they fail to explain how ancestral species became widespread in the first place. The mechanism proposed here, involving range expansion following competitive release via a "key innovation", may have operated in other Malagasy taxa with large numbers of species with small geographic ranges. [biodiversity hotspot; competition; Madagascar; microendemism; radiation.]. PMID:24578226

  20. Polarizing properties and structural characteristics of the cuticle of the scarab Beetle Chrysina gloriosa

    Energy Technology Data Exchange (ETDEWEB)

    Fernández del Río, Lía, E-mail: liafe@ifm.liu.se; Arwin, Hans; Järrendahl, Kenneth

    2014-11-28

    The scarab beetle Chrysina gloriosa is green with gold-colored stripes along its elytras. The properties of light reflected on these areas are investigated using Mueller-matrix spectroscopic ellipsometry. Both areas reflect light with high degree of left-handed polarization but this effect occurs for specular reflection for the gold-colored areas and for off-specular angles for the green areas. The colors and polarization phenomena originate from reflection of light in the cuticle and a structural analysis is presented to facilitate understanding of the different behaviors of these two areas. Scanning electron microscopy (SEM) images of the cross section of beetle cuticles show a multilayered structure. On the gold-colored areas the layers are parallel to the surface whereas on the green-colored areas they form cusp-like structures. Optical microscopy images show a rather flat surface in the gold-colored areas compared to the green-colored areas which display a net of polygonal cells with star-shaped cavities in the center. Each of the polygons corresponds to one of the cusps observed in the SEM images. Atomic force microscopy images of the star-shaped cavities are also provided. The roughness of the surface and the cusp-like structure of the green-colored areas are considered to cause scattering on this area. - Highlights: • Chrysina gloriosa reflects light with high degree of left-handed polarization. • Gold-colored areas are good specular reflectors whereas green-colored areas scatter light. • The cusp-like structure in the green areas is responsible for the scattering.

  1. Coal export facilitation

    International Nuclear Information System (INIS)

    There is a wide range of trade barriers, particularly tariffs, in current and potential coal market. Commonwealth departments in Australia play a crucial role in supporting government industry policies. This article summarises some of more recent activities of the Department of Primary Industries and Energy (DPIE) in facilitating the export of Australian Coals. Coal export facilitation activities are designed to assist the Australian coal industry by directing Commonwealth Government resources towards issues which would be inappropriate or difficult for the industry to address itself

  2. Dock leaf beetle, Gastrophysa viridula Deg., herbivory on Mossy Sorrel, Rumex confertus Willd: Induced plant volatiles and beetle orientation responses

    Science.gov (United States)

    The invasive weed Rumex confertus Willd. (mossy sorrel) is fed upon and severely defoliated by Gastrophysa viridula Deg. (dock leaf beetle), a highly promising biological control agent for this weed. We report volatile organic compound (VOC) induction when one leaf on R. confertus was damaged by G. ...

  3. ACTIVIDAD DIARIA DE COLONIZACIÓN DEL RECURSO ALIMENTICIO EN UN ENSAMBLAJE DE ESCARABAJOS COPRÓFAGOS (COLEOPTERA: SCARABAEIDAE EN LA AMAZONÍA COLOMBIANA Daily colonization of food resourses by Dung Beetles (Coleoptera: Scarabaeidae in the Colombian Amazone Region

    Directory of Open Access Journals (Sweden)

    JORGE ARI NORIEGA A

    Full Text Available Los escarabajos coprófagos pertenecientes a la familia Scarabaeidae presentan una fuerte competencia por el recurso alimenticio, debido a la baja agregación espacial y al carácter efímero del mismo. Un mecanismo que puede contribuir a diluir la competencia es la segregación temporal, conduciendo a una especialización en las horas de actividad. El objetivo de este trabajo fue estudiar la actividad diaria en un ensamblaje de escarabajos coprófagos en un bosque húmedo tropical en la amazonía colombiana. Se establecieron dos transectos lineales de 225 m y en cada uno se montaron diez tram-pas de caída por 24 horas, cebadas con excremento humano de dos investigadores, colectando su contenido cada hora, en la época de sequía. Se registraron un total de 23 especies, contenidas en diez géneros y cinco tribus. La abundancia del gremio de los cavadores fue mayor que la de los otros grupos. Igualmente, los escarabajos diurnos fueron más abundantes que los crepusculares y los nocturnos. Se presentaron algunas especies con horas de actividad muy específicas, evidenciando el problema de tomar tiempos de captura muy amplios donde se pierde el detalle de la restricción horaria. La riqueza y abundancia de especies en los cebos de los dos investigadores mostró diferencias, insinuando que pueden existir variaciones dentro del excremento humano, como cebo. Finalmente, se propone que la restricción en la actividad diaria puede ser un mecanismo importante de dilución de la competencia inter e intraespecífica, que facilita a las especies la coexistencia y repartición del recurso en el tiempo.Dung beetles belonging to the Scarabaeidae family have strong competition for food resources given the low spatial aggregation and ephemeral character of those resources. Temporal segregation through specialization in hours of activity is a mechanism that can decrease that competition. The objective of this paper is study the daily activity of an assemblage of

  4. Aggregation Algorithms in Heterogeneous Tables

    OpenAIRE

    Titus Felix FURTUNA; Ivan, Ion; Marian DARDALA

    2006-01-01

    The heterogeneous tables are most used in the problem of aggregation. A solution for this problem is to standardize these tables of figures. In this paper, we proposed some methods of aggregation based on the hierarchical algorithms.

  5. ASSESSMENT OF RECYCLED AGGREGATE CONCRETE

    OpenAIRE

    Ahmad Mujahid Ahmad Zaidi

    2009-01-01

    Used of recycled aggregate (RA) in concrete can be described in environmental protection and economical terms. The application of recycled aggregate to use in construction activities have been practice by developed European countries and also of some Asian countries. This paper reports the results of an experimental study on the mechanical properties of recycled aggregate concrete (RAC) as compared to natural aggregate concrete (NAC). The effects of size of RA on compressive strength were dis...

  6. Judgement aggregation and distributed thinking

    OpenAIRE

    Spiekermann, Kai

    2010-01-01

    In recent years, judgement aggregation has emerged as an important area of social choice theory. Judgement aggregation is concerned with aggregating sets of individual judgements over logically connected propositions into a set of collective judgements. It has been shown that even seemingly weak conditions on the aggregation function make it impossible to find functions that produce rational collective judgements from all possible rational individual judgements. This implies...

  7. Facilitating leadership team communication

    OpenAIRE

    Hedman, Eerika

    2015-01-01

    The purpose of this study is to understand and describe how to facilitate competent communication in leadership teamwork. Grounded in the premises of social constructionism and informed by such theoretical frameworks as coordinated management of meaning theory (CMM), dialogic organization development (OD), systemic-constructionist leadership, communication competence, and reflexivity, this study seeks to produce further insights into understanding leadership team communicati...

  8. From Teaching to Facilitation

    DEFF Research Database (Denmark)

    de Graaff, Erik

    2013-01-01

    A shift from teaching to learning is characteristic of the introduction of Problem Based Learning (PBL) in an existing school. As a consequence the teaching staff has to be trained in skills like facilitating group work and writing cases. Most importantly a change in thinking about teaching and...

  9. Aggregating governance indicators

    OpenAIRE

    Kaufmann, Daniel; Kraay, Aart; Zoido-Lobaton, Pablo

    1999-01-01

    In recent years the growing interest of academics and policymakers in governance has been reflected in the proliferation of cross-country indices measuring various aspects of governance. The authors explain how a simple variant of an unobserved components model can be used to combine the information from these different sources into aggregate governance indicators. The main advantage of this method us that it allows quantification of the precision of both individual sources of governance data...

  10. Aggregate Demand and Micro Behavior: A New Perspective on Keynesian Macroeconomics

    OpenAIRE

    Steven M. Fazzari; Piero Ferri; Edward Greenberg

    1999-01-01

    We analyze the microfoundations for Keynesian aggregate demand effects by considering the link between aggregate demand and firm production decisions under monopolistic competition. Macroeconomic equilibrium is characterized in a simple graphical framework that facilitates comparison of several major approaches to modeling Keynesian microfoundations, including equilibrium theories, "new Keynesian" sticky price models, and more traditional sticky wage approaches. We use this framework to devel...

  11. Study of Recycled Concrete Aggregates

    OpenAIRE

    Jitender Sharma; Sandeep Singla

    2014-01-01

    This paper describes the introduction and production of recycled concrete aggregates and its various applications in the construction industry. In this paper, properties of recycled aggregates and its comparison with the natural aggregates are also mentioned. Future recommendations about RCA are also included.

  12. Proteins aggregation and human diseases

    Science.gov (United States)

    Hu, Chin-Kun

    2015-04-01

    Many human diseases and the death of most supercentenarians are related to protein aggregation. Neurodegenerative diseases include Alzheimer's disease (AD), Huntington's disease (HD), Parkinson's disease (PD), frontotemporallobar degeneration, etc. Such diseases are due to progressive loss of structure or function of neurons caused by protein aggregation. For example, AD is considered to be related to aggregation of Aβ40 (peptide with 40 amino acids) and Aβ42 (peptide with 42 amino acids) and HD is considered to be related to aggregation of polyQ (polyglutamine) peptides. In this paper, we briefly review our recent discovery of key factors for protein aggregation. We used a lattice model to study the aggregation rates of proteins and found that the probability for a protein sequence to appear in the conformation of the aggregated state can be used to determine the temperature at which proteins can aggregate most quickly. We used molecular dynamics and simple models of polymer chains to study relaxation and aggregation of proteins under various conditions and found that when the bending-angle dependent and torsion-angle dependent interactions are zero or very small, then protein chains tend to aggregate at lower temperatures. All atom models were used to identify a key peptide chain for the aggregation of insulin chains and to find that two polyQ chains prefer anti-parallel conformation. It is pointed out that in many cases, protein aggregation does not result from protein mis-folding. A potential drug from Chinese medicine was found for Alzheimer's disease.

  13. Ground beetle (Coleoptera: Carabidae) assemblages in narrow hedgerows in a Danish agricultural landscape

    DEFF Research Database (Denmark)

    Lövei, G. L.; Magura, T.

    2015-01-01

    The role of hedgerows in supporting ground beetles (Coleoptera: Carabidae) in a Danish agricultural landscape was examined. Nine old, well established single-row hedges were selected for the study, three each of a native species (hawthorn, Crataegus monogyna), a non-native deciduous one (rowan...... beetle assemblages. The number of ground beetle individuals and species were significantly the highest in the hawthorn hedges and significantly decreased from the hedges with rowan toward the spruce hedges. The elevated number of ground beetle individuals and species in the hawthorn hedges were due...... to the forest specialist species, as the number of forest specialist ground beetle individuals and species were significantly higher in the hawthorn hedges compared to the hedges with rowan and spruce. Differences in the number of the grassland and the cropland specialist ground beetle individuals and species...

  14. Mountain Pine Beetle Dynamics in Lodgepole Pine Forests, Part 1: Course of an Infectation

    OpenAIRE

    Cole, Walter E; Amman, Gene D

    1980-01-01

    Much of this work is original research by the authors. However, published literature on the mountain pine beetle is reviewed with particular reference to epidemic infestations in lodgepole pine forests. The mountain pine beetle and lodgepole pine have evolved into an intensive and highly compatible relationship. Consequently, stand dynamics of lodgepole pine is a primary factor in the development of beetle epidemics. the diameter-growth relationship and the effects of environmental factors on...

  15. Dung beetle assemblages (Coleoptera, Scarabaeinae) in Atlantic forest fragments in southern Brazil

    OpenAIRE

    Renata C. Campos; Malva I. Medina Hernández

    2013-01-01

    Dung beetle assemblages (Coleoptera, Scarabaeinae) in Atlantic forest fragments in southern Brazil. The beetles of the subfamily Scarabaeinae are important organisms that participate in the cycle of decomposition, especially in tropical ecosystems. Most species feed on feces (dung) or carcasses (carrion) and are associated with animals that produce their food resources. Dung beetles are divided into three functional groups: rollers, tunnelers and dwellers. This present work aims to study the ...

  16. Yeast Associated with the Ambrosia Beetle, Platypus koryoensis, the Pest of Oak Trees in Korea

    OpenAIRE

    Yun, Yeo Hong; Suh, Dong Yeon; Yoo, Hun Dal; Oh, Man Hwan; Kim, Seong Hwan

    2015-01-01

    Oak tree death caused by symbiosis of an ambrosia beetle, Platypus koryoensis, and an ophiostomatoid filamentous fungus, Raffaelea quercus-mongolicae, has been a nationwide problem in Korea since 2004. In this study, we surveyed the yeast species associated with P. koryoensis to better understand the diversity of fungal associates of the beetle pest. In 2009, a total of 195 yeast isolates were sampled from larvae and adult beetles (female and male) of P. koryoensis in Cheonan, Goyang, and Paj...

  17. Darkling beetle populations (Tenebrionidae) of the Hanford site in southcentral Washington

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, L.E.; Woodley, N.; Sheldon, J.K.; Uresk, V.A.

    1978-02-01

    This 3-yr study documents the taxonomic composition, relative abundance, and seasonal distribution of darkling beetles occupying the Hanford Site in southcentral Washington. A taxonomic key and species diagnosis are provided to assist in identification by the nonspecialist. Analysis of food plant availability and selection serves to identify transfer pathways through beetle populations and permits construction of food web diagrams depicting the flow of materials through the darkling beetle component.

  18. Spruce Beetle (Dendroctonus rufipennis) Outbreak in Engelmann Spruce (Picea engelmannil) in Central Utah, 1986-1998

    OpenAIRE

    Dymerski, Alan D; Anhold, John A; Munson, Allen S

    2001-01-01

    Extensive Engelmann spruce (Picea engelmannii Parry ex Engelm.) mortality caused by the spruce beetle (Dendroctonus rufipennis Kirby) has been occurring at the southern end of the Wasatch Plateau in central Utah. This spruce beetle outbreak is the largest recorded in Utah history. An extensive ground survey was conducted in 1996 on the Manti-LaSal National Forest, Sanpete and Ferron Ranger Districts, to document mortality and impact of a major spruce beetle outbreak on post-outbreak forest co...

  19. Tracking an invasive honey bee pest: mitochondrial DNA variation in North American small hive beetles

    OpenAIRE

    Jay. D. Evans,; Jeff. S. Pettis,; Michael Hood, W.; Shimanuki, Hachiro

    2003-01-01

    International audience We describe the current and past distributions of North American small hive beetles (Aethina tumida) having two distinct mitochondrial DNA haplotypes. A collection of 539 hive beetles showed irregular distributions of these haplotypes across the southeastern US. Beetles from the first collections made in coastal South Carolina showed haplotype NA1, exclusively. This haplotype is less common in Georgia and was not observed in North Carolina. Later collections from thi...

  20. Dutch elm disease and elm bark beetles: a century of association

    OpenAIRE

    Santini A; Faccoli M

    2015-01-01

    Bark beetles of the genus Scolytus Geoffroy are the main vectors of the fungus Ophiostoma ulmi s.l., which causes the Dutch elm disease. The large and small elm bark beetles - S. scolytus (F.) and S. multistriatus (Marsham), respectively - are the most common and important species spreading the pathogen worldwide. The success of the pathogen-insect interactions is mainly due to the characteristic reproductive behavior of the elm bark beetles, which, however, largely depends on the occurrence ...

  1. Population Dynamics of Bean Leaf Beetle, Cerotoma trifurcata (Coleoptera: Chrysomelidae on Edamame Soybean Plants In Nebraska

    Directory of Open Access Journals (Sweden)

    Bamphitlhi Tiroesele

    2013-02-01

    Full Text Available Edamame soybeans are a speciality food item for fresh and processed markets and they are harvested at a physiologically immature (R6 stage. Bean leaf beetle, Cerotoma trifurcata, is a sporadic pest of soybean in Nebraska, however, its pest status and abundance has increased in the recent years due to an increase in soybean acreage. This was a field experiment aimed at determining the population growth rate of bean leaf beetle on two edamame soybean cultivars, ‘Butterbeans’ and ‘Envy,’ at two planting dates during 2004 and 2005 in Nebraska. The population growth of beetles was significantly higher on 'Butterbeans' than on 'Envy' for both the first and second planting periods in both 2004 and 2005 seasons. The beetle infestation differences were noticed on plants at the late reproductive growth stages, R5 and R6. Additionally, the beetle infestation on 'Butterbeans' growth stages in 2004 and 2005 was significantly different for the first and second planting dates. On average, the beetles were higher on plants at the late reproductive stages than the other stages for first and second planting periods. Similarly, ‘Envy’ growth stages showed significant difference in beetle infestation during the first and second planting dates. Significantly high beetle infestations were observed at the vegetative growth stages. The study revealed that population growth of bean leaf beetles on edamame soybeans is affected by the planting date, season and cultivar choice.

  2. Repeated evolution of crop theft in fungus-farming ambrosia beetles.

    Science.gov (United States)

    Hulcr, Jiri; Cognato, Anthony I

    2010-11-01

    Ambrosia beetles, dominant wood degraders in the tropics, create tunnels in dead trees and employ gardens of symbiotic fungi to extract nutrients from wood. Specificity of the beetle-fungus relationship has rarely been examined, and simple vertical transmission of a specific fungal cultivar by each beetle species is often assumed in literature. We report repeated evolution of fungal crop stealing, termed mycocleptism, among ambrosia beetles. The mycocleptic species seek brood galleries of other species, and exploit their established fungal gardens by tunneling through the ambient mycelium-laden wood. Instead of carrying their own fungal sybmbionts, mycocleptae depend on adopting the fungal assemblages of their host species, as shown by an analysis of fungal DNA from beetle galleries. The evidence for widespread horizontal exchange of fungi between beetles challenges the traditional concept of ambrosia fungi as species-specific symbionts. Fungus stealing appears to be an evolutionarily successful strategy. It evolved independently in several beetle clades, two of which have radiated, and at least one case was accompanied by a loss of the beetles' fungus-transporting organs. We demonstrate this using the first robust phylogeny of one of the world's largest group of ambrosia beetles, Xyleborini. PMID:20633043

  3. Social encapsulation of beetle parasites by Cape honeybee colonies (Apis mellifera capensis Esch.)

    Science.gov (United States)

    Neumann, P.; Pirk, C. W. W.; Hepburn, H. R.; Solbrig, A. J.; Ratnieks, F. L. W.; Elzen, P. J.; Baxter, J. R.

    2001-05-01

    Worker honeybees (Apis mellifera capensis) encapsulate the small hive beetle (Aethina tumida), a nest parasite, in propolis (tree resin collected by the bees). The encapsulation process lasts 1-4 days and the bees have a sophisticated guarding strategy for limiting the escape of beetles during encapsulation. Some encapsulated beetles died (4.9%) and a few escaped (1.6%). Encapsulation has probably evolved because the small hive beetle cannot easily be killed by the bees due to its hard exoskeleton and defensive behaviour.

  4. Mindfulness for group facilitation

    DEFF Research Database (Denmark)

    Adriansen, Hanne Kirstine; Krohn, Simon

    2014-01-01

    In this paper, we argue that mindfulness techniques can be used for enhancing the outcome of group performance. The word mindfulness has different connotations in the academic literature. Broadly speaking there is ‘mindfulness without meditation’ or ‘Western’ mindfulness which involves active...... thinking and ‘Eastern’ mindfulness which refers to an open, accepting state of mind, as intended with Buddhist-inspired techniques such as meditation. In this paper, we are interested in the latter type of mindfulness and demonstrate how Eastern mindfulness techniques can be used as a tool for facilitation....... A brief introduction to the physiology and philosophy of Eastern mindfulness constitutes the basis for the arguments of the effect of mindfulness techniques. The use of mindfulness techniques for group facilitation is novel as it changes the focus from individuals’ mindfulness practice to that of...

  5. Facilitating Knowledge Sharing

    OpenAIRE

    Holdt Christensen, Peter

    2005-01-01

    Abstract This paper argues that knowledge sharing can be conceptualized as different situations of exchange in which individuals relate to each other in different ways, involving different rules, norms and traditions of reciprocity regulating the exchange. The main challenge for facilitating knowledge sharing is to ensure that the exchange is seen as equitable for the parties involved, and by viewing the problems of knowledge sharing as motivational problems situated in different organization...

  6. A common theme in extracellular fluids of beetles: extracellular superoxide dismutases crucial for balancing ROS in response to microbial challenge.

    Science.gov (United States)

    Gretscher, René R; Streicher, Priska E; Strauß, Anja S; Wielsch, Natalie; Stock, Magdalena; Wang, Ding; Boland, Wilhelm; Burse, Antje

    2016-01-01

    Extracellular Cu/Zn superoxide dismutases (SODs) are critical for balancing the level of reactive oxygen species in the extracellular matrix of eukaryotes. In the present study we have detected constitutive SOD activity in the haemolymph and defensive secretions of different leaf beetle species. Exemplarily, we have chosen the mustard leaf beetle, Phaedon cochleariae, as representative model organism to investigate the role of extracellular SODs in antimicrobial defence. Qualitative and quantitative proteome analyses resulted in the identification of two extracellular Cu/Zn SODs in the haemolymph and one in the defensive secretions of juvenile P. cochleariae. Furthermore, quantitative expression studies indicated fat body tissue and defensive glands as the main synthesis sites of these SODs. Silencing of the two SODs revealed one of them, PcSOD3.1, as the only relevant enzyme facilitating SOD activity in haemolymph and defensive secretions in vivo. Upon challenge with the entomopathogenic fungus, Metarhizium anisopliae, PcSOD3.1-deficient larvae exhibited a significantly higher mortality compared to other SOD-silenced groups. Hence, our results serve as a basis for further research on SOD regulated host-pathogen interactions. In defensive secretions PcSOD3.1-silencing affected neither deterrent production nor activity against fungal growth. Instead, we propose another antifungal mechanism based on MRJP/yellow proteins in the defensive exudates. PMID:27068683

  7. Monitoring presence and advance of the alien invasive western corn rootworm beetle in eastern Slovenia with highly sensitive Metcalf traps.

    Science.gov (United States)

    Hummel, H E; Urek, G; Modic, S; Hein, D F

    2005-01-01

    The American Chrysomelid beetle Diabrotica virgifera virgifera LeConte (D.v.v.), also called the western corn rootworm, spread from the location of its original introduction into Europe, Belgrade airport (BACA 1993), in all directions. Within a decade it occupied almost all countries of South-eastern and Central Europe. However, it reached Slovenia as late as 2003: Only 19 specimen were found in maize fields of the eastern and also western provinces. Already in the summer of 2004, their number had risen to 386 which were mainly found in the eastern provinces near the borders to Croatia, Austria and Hungary. For their monitoring, a simple trap is being described which can be acquired in high numbers at a very low price and can guaranty a most sensitive detection of beetles. The Metcalf cup trap which in Slovenia so far has been unknown performed the task of monitoring quite well at five locations. It will also facilitate the future search for new and increasing infestations. Comparing 2004 with the year 2003, D.v.v. expanded its range in eastern Slovenia by about 15 km. These new infestations will include territories in which fields of the regionally Important oil seed pumpkin Cucurbita pepo are located. With important traffic connections between South-eastern and Central Europe, Slovenia will occupy a bridgehead function in the preventive protection of maize from D.v.v. spreading into more northerly European regions including western Austria and southern Germany. PMID:16628904

  8. Absorption Spectra of Astaxanthin Aggregates

    CERN Document Server

    Olsina, Jan; Minofar, Babak; Polivka, Tomas; Mancal, Tomas

    2012-01-01

    Carotenoids in hydrated polar solvents form aggregates characterized by dramatic changes in their absorption spectra with respect to monomers. Here we analyze absorption spectra of aggregates of the carotenoid astaxanthin in hydrated dimethylsulfoxide. Depending on water content, two types of aggregates were produced: H-aggregates with absorption maximum around 390 nm, and J-aggregates with red-shifted absorption band peaking at wavelengths >550 nm. The large shifts with respect to absorption maximum of monomeric astaxanthin (470-495 nm depending on solvent) are caused by excitonic interaction between aggregated molecules. We applied molecular dynamics simulations to elucidate structure of astaxanthin dimer in water, and the resulting structure was used as a basis for calculations of absorption spectra. Absorption spectra of astaxanthin aggregates in hydrated dimethylsulfoxide were calculated using molecular exciton model with the resonance interaction energy between astaxanthin monomers constrained by semi-e...

  9. Phylogeny of ambrosia beetle symbionts in the genus Raffaelea.

    Science.gov (United States)

    Dreaden, Tyler J; Davis, John M; de Beer, Z Wilhelm; Ploetz, Randy C; Soltis, Pamela S; Wingfield, Michael J; Smith, Jason A

    2014-12-01

    The genus Raffaelea was established in 1965 when the type species, Raffaelea ambrosia, a symbiont of Platypus ambrosia beetles was described. Since then, many additional ambrosia beetle symbionts have been added to the genus, including the important tree pathogens Raffaelea quercivora, Raffaelea quercus-mongolicae, and Raffaelea lauricola, causal agents of Japanese and Korean oak wilt and laurel wilt, respectively. The discovery of new and the dispersal of described species of Raffaelea to new areas, where they can become invasive, presents challenges for diagnosticians as well as plant protection and quarantine efforts. In this paper, we present the first comprehensive multigene phylogenetic analysis of Raffaelea. As it is currently defined, the genus was found to not be monophyletic. On the basis of this work, Raffaelea sensu stricto is defined and the affinities of undescribed isolates are considered. PMID:25457944

  10. Simulation of light scattering from exoskeletons of scarab beetles.

    Science.gov (United States)

    Valyukh, Sergiy; Arwin, Hans; Järrendahl, Kenneth

    2016-03-21

    An approach for simulation of light scattering from beetles exhibiting structural colors originating from periodic helicoidal structures is presented. Slight irregularities of the periodic structure in the exoskeleton of the beetles are considered as a major cause of light scattering. Two sources of scattering are taken into account: surface roughness and volume non-uniformity. The Kirchhoff approximation is applied to simulate the effect of surface roughness. To describe volume non-uniformity, the whole structure is modeled as a set of domains distributed in space in different orientations. Each domain is modeled as an ideal uniformly twisted uniaxial medium and differs from each other by the pitch. Distributions of the domain parameters are assumed to be Gaussian. The analysis is performed using the Mueller matrix formalism which, in addition to spectral and spatial characteristics, also provides polarization properties of the scattered light. PMID:27136777

  11. Effect of gamma irradiation on khapra beetle Trogoderma granarium everts

    International Nuclear Information System (INIS)

    The effect of gamma irradiation on all developmental stages of khapra beetle was examined. The results showed that when higher doses were applied and immature stages were treated the developmental time, larval and pupal mortality and adults' deformation were increased. Whereas, the fecundity and fertility of the emerged adults resulted from the treatment of immature stages, were increased when old eggs, larvae and pupae were treated with low doses. When newly emerged adults were irradiated the longevity of the male and the female was not affected, while the fecundity and fertility were declined especially when high doses were applied. The female of khapra beetle was more radiosensitive than the male, regardless of the applied dose or/and the treated developmental stage. (author)

  12. Approaches to mimic the metallic sheen in beetles

    DEFF Research Database (Denmark)

    Lenau, Torben Anker; Aggerbeck, Martin; Nielsen, Steffen

    2009-01-01

    A range of different beetles exhibits brilliant colours and metallic sheen. One of the most spectacular species is the Plusiotis resplendens from Central America with gold metal appearance. The beetle shells are made from chitin and have a number of unique properties that apart from spectacular...... aesthetic effects include metal sheen from non-metal surfaces combined with electric and thermal insulation. The reflection mechanism has been studied by a number of authors and is well understood. Basically there are 2 different reflection principles. One is the multilayer reflector where alternating...... layers have high and low refractive index. The other is the Bouligand structure where birefringent chiral nanofibres are organised in spiral structures. The paper describes work done to explore different approaches to mimic these structures using polymer based materials and production methods that are...

  13. Associational Patterns of Scavenger Beetles to Decomposition Stages.

    Science.gov (United States)

    Zanetti, Noelia I; Visciarelli, Elena C; Centeno, Nestor D

    2015-07-01

    Beetles associated with carrion play an important role in recycling organic matter in an ecosystem. Four experiments on decomposition, one per season, were conducted in a semirural area in Bahía Blanca, Argentina. Melyridae are reported for the first time of forensic interest. Apart from adults and larvae of Scarabaeidae, thirteen species and two genera of other coleopteran families are new forensic records in Argentina. Diversity, abundance, and species composition of beetles showed differences between stages and seasons. Our results differed from other studies conducted in temperate regions. Four guilds and succession patterns were established in relation to decomposition stages and seasons. Dermestidae (necrophages) predominated in winter during the decomposition process; Staphylinidae (necrophiles) in Fresh and Bloat stages during spring, summer, and autumn; and Histeridae (necrophiles) and Cleridae (omnivores) in the following stages during those seasons. Finally, coleopteran activity, diversity and abundance, and decomposition rate change with biogeoclimatic characteristics, which is of significance in forensics. PMID:26174466

  14. The Japanese jewel beetle: a painter's challenge

    International Nuclear Information System (INIS)

    Colours as dynamic as the metallic-like hues adorning the Japanese jewel beetle have never been captured on canvas before. Unlike, and unmatched by, the chemical pigments of the artist's palette, the effect is generated by layered microstructures that refract and reflect light to make colour visible. Exclusive to nature for millions of years, such jewel-like colouration is only now being introduced to art. Sustained scientific research into nature's iridescent multilayer reflectors has recently led to the development and manufacture of analogous synthetic structures, notably innovative light interference flakes. For the first time this novel technology offers artists the exciting, yet challenging, potential to accurately depict nature's iridescence. Mimicking the Japanese jewel beetle by using paints with embedded flakes, we demonstrate that the resulting painting, just like the model, displays iridescent colours that shift with minute variation of the angle of light and viewing. (paper)

  15. Aggregate Demand and Supply

    OpenAIRE

    Farmer, Roger E.A.

    2007-01-01

    This paper is part of a broader project that provides a microfoundation to the General Theory of J.M. Keynes. I call this project 'old Keynesian economics' to distinguish it from new-Keynesian economics, a theory that is based on the idea that to make sense of Keynes we must assume that prices are sticky. I describe a multi-good model in which I interpret the definitions of aggregate demand and supply found in the General Theory through the lens of a search theory of the labor market. I argue...

  16. Aggregation of smooth preferences

    OpenAIRE

    Norman Schofield

    1998-01-01

    Suppose p is a smooth preference profile (for a society, N) belonging to a domain PN. Let be a voting rule, and (p)(x) be the set of alternatives in the space, W, which is preferred to x. The equilibrium E((p)) is the set {x∈W:(p)(x) is empty}. A sufficient condition for existence of E((p)) when p is convex is that a "dual", or generalized gradient, d(p)(x), is non-empty at all x. Under certain conditions the dual "field", d(p), admits a "social gradient field" (p). is called an "aggregator" ...

  17. Concrete = aggregate, cement, water?

    International Nuclear Information System (INIS)

    Concrete for the Temelin nuclear power plant is produced to about 70 different formulae. For quality production, homogeneous properties of aggregates, accurate proportioning devices, technological discipline and systematic inspections and tests should be assured. The results are reported of measuring compression strength after 28 days for different concrete samples. The results of such tests allow reducing the proportion of cement, which brings about considerable savings. Reduction in cement quantities can also be achieved by adding ash to the concrete mixes. Ligoplast, a plasticizer addition is used for improving workability. (M.D). 8 figs

  18. Expert and novice facilitated modelling

    DEFF Research Database (Denmark)

    Tavella, Elena; Papadopoulos, Thanos

    2015-01-01

    This paper provides an empirical study based on action research in which expert and novice facilitators in facilitated modelling workshops are compared. There is limited empirical research analysing the differences between expert and novice facilitators. Aiming to address this gap we study the...... behaviour of one expert and two novice facilitators during a Viable System Model workshop. The findings suggest common facilitation patterns in the behaviour of experts and novices. This contrasts literature claiming that experts and novices behave and use their available knowledge differently, and...... facilitation strategies in contexts in which external, expert facilitation is not always possible are also discussed, and limitations of this study are provided....

  19. Chemical Defense of an Ozaenine Bombardier Beetle From New Guinea

    OpenAIRE

    Jerrold Meinwald; Blankespoor, Curtis L.; Maria Eisner; Thomas Eisner; Braden Roach; Aneschansley, Daniel J.; Ball, George E.

    1989-01-01

    We had occasion recently to study 3 live specimens of Pseudozaena orientalis opaca, an ozaenine carabid beetle (subfamily Paussinae, tribe Ozaenini) from New Guinea, and report here on the biology and chemistry of its defensive spray mechanism. A number of New World ozaenines had previously been studied chemically and shown to be “bombardiers” that discharge a hot quinonoid mixture (Aneshansley et al. 1969, 1983; Eisner and Aneshansley 1982; Eisner et al. 1977; Roach et al. 1979). Pseudozaena...

  20. The Evolution of Functionally Redundant Species; Evidence from Beetles

    OpenAIRE

    Scheffer, M.; Vergnon, R.O.H.; Nes, van, S.I.; Cuppen, J.G.M.; Peeters, E.T.H.M.; Leijs, R.; Nilsson, A. N.

    2015-01-01

    While species fulfill many different roles in ecosystems, it has been suggested that numerous species might actually share the same function in a near neutral way. So-far, however, it is unclear whether such functional redundancy really exists. We scrutinize this question using extensive data on the world's 4168 species of diving beetles. We show that across the globe these animals have evolved towards a small number of regularly-spaced body sizes, and that locally co-existing species are eit...

  1. Taxonomy Icon Data: red flour beetle [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available red flour beetle Tribolium castaneum Arthropoda Tribolium_castaneum_L.png Tribolium..._castaneum_NL.png Tribolium_castaneum_S.png Tribolium_castaneum_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Triboliu...m+castaneum&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Tribolium+castaneum&t=N...L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Tribolium+castaneum&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Tribolium+castaneum&t=NS ...

  2. Cost of flight and the evolution of stag beetle weaponry

    OpenAIRE

    Goyens, Jana; Van Wassenbergh, Sam; Dirckx, Joris; Aerts, Peter

    2015-01-01

    Male stag beetles have evolved extremely large mandibles in a wide range of extraordinary shapes. These mandibles function as weaponry in pugnacious fights for females. The robust mandibles of Cyclommatus metallifer are as long as their own body and their enlarged head houses massive, hypertrophied musculature. Owing to this disproportional weaponry, trade-offs exist with terrestrial locomotion: running is unstable and approximately 40% more costly. Therefore, flying is most probably essentia...

  3. Using malaise traps to sample ground beetles (Coleoptera: Carabidae).

    Energy Technology Data Exchange (ETDEWEB)

    Ulyshen, Michael D., James L. Hanula, and Scott Horn

    2005-01-01

    Pitfall traps provide an easy and inexpensive way to sample ground-dwelling arthropods (Spence and Niemela 1994; Spence et al. 1997; Abildsnes and Tommeras 2000) and have been used exclusively in many studies of the abundance and diversity of ground beetles (Coleoptera: Carabidae). Despite the popularity of this trapping technique, pitfall traps have many disadvantages. For example, they often fail to collect both small (Spence and Niemela 1994) and trap-shy species (Benest 1989), eventually deplete the local carabid population (Digweed et al. 1995), require a species to be ground-dwelling in order to be captured (Liebherr and Mahar 1979), and produce different results depending on trap diameter and material, type of preservative used, and trap placement (Greenslade 1964; Luff 1975; Work et al. 2002). Further complications arise from seasonal patterns of movement among the beetles themselves (Maelfait and Desender 1990), as well as numerous climatic factors, differences in plant cover, and variable surface conditions (Adis 1979). Because of these limitations, pitfall trap data give an incomplete picture of the carabid community and should be interpreted carefully. Additional methods, such as use of Berlese funnels and litter washing (Spence and Niemela 1994), collection from lights (Usis and MacLean 1998), and deployment of flight intercept devices (Liebherr and Mahar 1979; Paarmann and Stork 1987), should be incorporated in surveys to better ascertain the species composition and relative numbers of ground beetles. Flight intercept devices, like pitfall traps, have the advantage of being easy to use and replicate, but their value to carabid surveys is largely unknown. Here we demonstrate the effectiveness of Malaise traps for sampling ground beetles in a bottomland hardwood forest.

  4. Using malaise traps to sample ground beetles (Coleoptera. Carabidae)

    Energy Technology Data Exchange (ETDEWEB)

    Ulyshen, Michael D. [USDA Forest Service, Savannah River, New Ellenton, SC (United States); Hanula, James L. [USDA Forest Service, Savannah River, New Ellenton, SC (United States); Horn, Scott [USDA Forest Service, Savannah River, New Ellenton, SC (United States)

    2012-04-02

    Pitfall traps provide an easy and inexpensive way to sample ground-dwelling arthropods (Spence and Niemela 1994; Spence et al. 1997; Abildsnes and Tommeras 2000) and have been used exclusively in many studies of the abundance and diversity of ground beetles (Coleoptera: Carabidae). Despite the popularity of this trapping technique, pitfall traps have many disadvantages. For example, they often fail to collect both small (Spence and Niemela 1994) and trap-shy species (Benest 1989), eventually deplete the local carabid population (Digweed et al. 1995), require a species to be ground-dwelling in order to be captured (Liebherr and Mahar 1979), and produce different results depending on trap diameter and material, type of preservative used, and trap placement (Greenslade 1964; Luff 1975; Work et al. 2002). Further complications arise from seasonal patterns of movement among the beetles themselves (Maelfait and Desender 1990), as well as numerous climatic factors, differences in plant cover, and variable surface conditions (Adis 1979). Because of these limitations, pitfall trap data give an incomplete picture of the carabid community and should be interpreted carefully. Additional methods, such as use of Berlese funnels and litter washing (Spence and Niemela 1994), collection from lights (Usis and MacLean 1998), and deployment of flight intercept devices (Liebherr and Mahar 1979; Paarmann and Stork 1987), should be incorporated in surveys to better ascertain the species composition and relative numbers of ground beetles. Flight intercept devices, like pitfall traps, have the advantage of being easy to use and replicate, but their value to carabid surveys is largely unknown. Here we demonstrate the effectiveness of Malaise traps for sampling ground beetles in a bottomland hardwood forest.

  5. Hit‐and‐run trophallaxis of small hive beetles

    OpenAIRE

    Neumann, Peter; Naef, J.; Crailsheim, K; Crewe, RM; Pirk, CWW

    2015-01-01

    Abstract Some parasites of social insects are able to exploit the exchange of food between nestmates via trophallaxis, because they are chemically disguised as nestmates. However, a few parasites succeed in trophallactic solicitation although they are attacked by workers. The underlying mechanisms are not well understood. The small hive beetle (=SHB), Aethina tumida, is such a parasite of honey bee, Apis mellifera, colonies and is able to induce trophallaxis. Here, we investigate whether SHB ...

  6. Large carrion beetles (Coleoptera, Silphidae) in Western Europe: a review

    OpenAIRE

    Dekeirsschieter, Jessica; Verheggen, François; Lognay, Georges; Haubruge, Eric

    2011-01-01

    This review focuses on carrion beetles (Coleoptera, Silphidae) of the Western Palearctic and their potential use in forensic entomology as bioindicators. Few studies have looked at Silphidae in forensic context and investigations. However, some Silphidae present the desirable characteristics of some Diptera used in postmortem estimates and thus may extend the minimum postmortem interval (PMImin). We review here the taxonomy and distribution of Western Palearctic Silphidae. The anatomical and...

  7. Large carrion beetles (Coleoptera, Silphidae) in Western Europe: a review

    OpenAIRE

    Dekeirsschieter, J.; Verheggen, F.; Lognay, G.; Haubruge, E.

    2011-01-01

    This review focuses on carrion beetles (Coleoptera, Silphidae) of the Western Palearctic and their potential use in forensic entomology as bioindicators. Few studies have looked at Silphidae in forensic context and investigations. However, some Silphidae present the desirable characteristics of some Diptera used in postmortem estimates and thus may extend the minimum postmortem interval (PMImin). We review here the taxonomy and distribution of Western Palearctic Silphidae. The anatomical and ...

  8. Coffee Berry Borer Joins Bark Beetles in Coffee Klatch

    OpenAIRE

    Jaramillo, Juliana; Torto, Baldwyn; Mwenda, Dickson; Troeger, Armin; Borgemeister, Christian; Poehling, Hans-Michael; Francke, Wittko

    2013-01-01

    Unanswered key questions in bark beetle-plant interactions concern host finding in species attacking angiosperms in tropical zones and whether management strategies based on chemical signaling used for their conifer-attacking temperate relatives may also be applied in the tropics. We hypothesized that there should be a common link in chemical signaling mediating host location by these Scolytids. Using laboratory behavioral assays and chemical analysis we demonstrate that the yellow-orange exo...

  9. Effects of Pathogens and Bark Beetles on Forests

    OpenAIRE

    Goheen, D J; Hansen, E M

    1993-01-01

    This chapter addresses the varied roles that root pathogens and bark beetles play in western coniferous forests as (1) regulators of ecological structure and processes, (2) arbiters of management success and (3) agents of significant economic loss. Pathologists, entomologists, and forest managers often speak of the "impact" of fungal and insect "pests" on forest values. This terminology carries connotations of death and destruction that reflect only part of the role that these organisms play ...

  10. Influence of Mountain Pine Beetle on Fuels, Foliar Fuel Moisture Content, and Litter and Volatile Terpenes in Whitebark Pine

    OpenAIRE

    Toone, Chelsea

    2013-01-01

    Mountain pine beetle (Dendroctonus ponderosae Hopkins) has caused extensive tree mortality in whitebark pine (Pinus albicaulis Engelm) forests. Previous studies conducted in various conifer forests have shown that fine surface fuels are significantly altered during a bark beetle outbreak. Bark beetle activity in conifer stands has also been shown to alter foliar fuel moisture content and chemistry over the course of the bark beetle rotation.The objective of this study was to evaluate changes ...

  11. ROVE BEETLES (COLEOPTERA, STAPHYLINIDAE AND THEIR MEDICAL IMPORTANCE

    Directory of Open Access Journals (Sweden)

    B. Janbakhsh

    1977-06-01

    Full Text Available Rove beetle dermatitis produced by the family Staphylinidae genus Paederus has world- wide distribution some one hundred species of Paederus have been found, but it is believed that only 30 of these produce dermatitis. Up to 1976 three species of paederus have been found in Iran as: P. fusciped Curtis; P. pietschmanni Bershaner , and P. spectabilis Kraatz . Observations on the biology of Paederus SPP have shown that the greatest activity coincides with a high degree of humidity during the hot season. Some species seem to be attracted to artificial light. The most common pathological feature caused by rose beetles is a viscular dermatitis Eye lesions may occur, but they are the result of spread of the irritant with the fingers, after the insect was crushed on the skin, therefore secondary infection. Experiments have shown that dermatitis only develops when a rove beetle is crushed on the haemolymph. The vesicant substance is pederin which is distinct from cantharidin in terns of its biological, physical, and chemical propertics.

  12. DETECTION OF DRUGSTORE BEETLES IN 9975 PACKAGES USING ACOUSTIC EMISSIONS

    Energy Technology Data Exchange (ETDEWEB)

    Shull, D.

    2013-03-04

    This report documents the initial feasibility tests performed using a commercial acoustic emission instrument for the purpose of detecting beetles in Department of Energy 9975 shipping packages. The device selected for this testing was a commercial handheld instrument and probe developed for the detection of termites, weevils, beetles and other insect infestations in wooden structures, trees, plants and soil. The results of two rounds of testing are presented. The first tests were performed by the vendor using only the hand-held instrument’s indications and real-time operator analysis of the audio signal content. The second tests included hands-free positioning of the instrument probe and post-collection analysis of the recorded audio signal content including audio background comparisons. The test results indicate that the system is promising for detecting the presence of drugstore beetles, however, additional work would be needed to improve the ease of detection and to automate the signal processing to eliminate the need for human interpretation. Mechanisms for hands-free positioning of the probe and audio background discrimination are also necessary for reliable detection and to reduce potential operator dose in radiation environments.

  13. Rove beetles of medical importance in Brazil (Coleoptera, Staphylinidae, Paederinae

    Directory of Open Access Journals (Sweden)

    Juliana S. Vieira

    2014-09-01

    Full Text Available Rove beetles of medical importance in Brazil (Coleoptera, Staphylinidae, Paederinae. The rove beetles of the genus Paederus Fabricius, 1775 are the most important group within Coleoptera causing dermatitis around the world. The medical importance of Paederus depends on its toxic hemolymph released when these beetles are crushed on human skin. The effects are mainly dermatitis linearis and some sporadic cases of conjunctivitis. In Brazil seven species of Paederus are known to cause dermatitis: P. amazonicus Sharp, 1876, P. brasiliensis Erichson, 1840, P. columbinus Laporte, 1835, P. ferus Erichson, 1840, P. mutans Sharp, 1876, P. protensus Sharp, 1876 stat. rev., and Paederus rutilicornis Erichson, 1840. Paederus mutans and P. protensus are for the first time recorded as of medical importance, whereas the record of P. rutilicornis in Brazil is doubtful. All seven species are redescribed and a dichotomous key is provided. The geographic distributions of all species are documented. The results provided here include the most recent and relevant taxonomic revision of Paederus of the Neotropical region, the first identification key for Brazilian species and the increase of recorded species of medical importance in the world.

  14. Facilitation as a teaching strategy : experiences of facilitators

    Directory of Open Access Journals (Sweden)

    E Lekalakala-Mokgele

    2006-09-01

    Full Text Available Changes in nursing education involve the move from traditional teaching approaches that are teacher-centred to facilitation, a student centred approach. The studentcentred approach is based on a philosophy of teaching and learning that puts the learner on centre-stage. The aim of this study was to identify the challenges of facilitators of learning using facilitation as a teaching method and recommend strategies for their (facilitators development and support. A qualitative, explorative and contextual design was used. Four (4 universities in South Africa which utilize facilitation as a teaching/ learning process were identified and the facilitators were selected to be the sample of the study. The main question posed during in-depth group interviews was: How do you experience facilitation as a teaching/learning method?. Facilitators indicated different experiences and emotions when they first had to facilitate learning. All of them indicated that it was difficult to facilitate at the beginning as they were trained to lecture and that no format for facilitation was available. They experienced frustrations and anxieties as a result. The lack of knowledge of facilitation instilled fear in them. However they indicated that facilitation had many benefits for them and for the students. Amongst the ones mentioned were personal and professional growth. Challenges mentioned were the fear that they waste time and that they do not cover the content. It is therefore important that facilitation be included in the training of nurse educators.

  15. Taurine and platelet aggregation

    International Nuclear Information System (INIS)

    Taurine is a putative neurotransmitter or neuromodulator. The endogenous taurine concentration in human platelets, determined by amino acid analysis, is 15 μM/g. In spite of this high level, taurine is actively accumulated. Uptake is saturable, Na+ and temperature dependent, and suppressed by metabolic inhibitors, structural analogues, and several classes of centrally active substances. High, medium and low affinity transport processes have been characterized, and the platelet may represent a model system for taurine transport in the CNS. When platelets were incubated with 14C-taurine for 30 minutes, then resuspended in fresh medium and reincubated for one hour, essentially all of the taurine was retained within the cells. Taurine, at concentrations ranging from 10-1000 μM, had no effect on platelet aggregation induced by ADP or epinephrine. However, taurine may have a role in platelet aggregation since 35-39% of the taurine taken up by human platelets appears to be secreted during the release reaction induced by low concentrations of either epinephrine or ADP, respectively. This release phenomenon would imply that part of the taurine taken up is stored directly in the dense bodies of the platelet

  16. Facilitated Asymmetric Exclusion

    OpenAIRE

    Gabel, Alan; Krapivsky, P. L.; Redner, S.

    2010-01-01

    We introduce a class of facilitated asymmetric exclusion processes in which particles are pushed by neighbors from behind. For the simplest version in which a particle can hop to its vacant right neighbor only if its left neighbor is occupied, we determine the steady state current and the distribution of cluster sizes on a ring. We show that an initial density downstep develops into a rarefaction wave that can have a jump discontinuity at the leading edge, while an upstep results in a shock w...

  17. Essence: Facilitating Software Innovation

    DEFF Research Database (Denmark)

    Aaen, Ivan

    2008-01-01

      This paper suggests ways to facilitate creativity and innovation in software development. The paper applies four perspectives – Product, Project, Process, and People –to identify an outlook for software innovation. The paper then describes a new facility–Software Innovation Research Lab (SIRL......) – and a new method concept for software innovation – Essence – based on views, modes, and team roles. Finally, the paper reports from an early experiment using SIRL and Essence and identifies further research....

  18. Characterization of the effects of isoprostanes on platelet aggregation in human whole blood

    OpenAIRE

    Cranshaw, Julius H; Evans, Timothy W.; Mitchell, Jane A.

    2001-01-01

    We tested the effects of 11 commercially-available isoprostanes on platelet aggregation directly or when triggered by the thromboxane receptor agonist U46619 or collagen in healthy human citrated blood using a whole blood aggregometer.None of the isoprostanes tested triggered aggregation alone, nor facilitated aggregation by a sub-threshold dose of U46619 or collagen. Five isoprostanes inhibited aggregation (rank order of potency 8-iso PGE1>8-iso PGE2>8-iso PGF2α>8-iso PGF3α>8-iso-13,14-dihyd...

  19. Holographic characterization of protein aggregates

    Science.gov (United States)

    Wang, Chen; Zhong, Xiao; Ruffner, David; Stutt, Alexandra; Philips, Laura; Ward, Michael; Grier, David

    Holographic characterization directly measures the size distribution of subvisible protein aggregates in suspension and offers insights into their morphology. Based on holographic video microscopy, this analytical technique records and interprets holograms of individual aggregates in protein solutions as they flow down a microfluidic channel, without requiring labeling or other exceptional sample preparation. The hologram of an individual protein aggregate is analyzed in real time with the Lorenz-Mie theory of light scattering to measure that aggregate's size and optical properties. Detecting, counting and characterizing subvisible aggregates proceeds fast enough for time-resolved studies, and lends itself to tracking trends in protein aggregation arising from changing environmental factors. No other analytical technique provides such a wealth of particle-resolved characterization data in situ. Holographic characterization promises accelerated development of therapeutic protein formulations, improved process control during manufacturing, and streamlined quality assurance during storage and at the point of use. Mrsec and MRI program of the NSF, Spheryx Inc.

  20. Assessing meteorological key factors influencing crop invasion by pollen beetle (

    Directory of Open Access Journals (Sweden)

    Jürgen Junk

    2016-09-01

    Full Text Available The pollen beetle, Meligethes aeneus F. (Coleoptera: Nitidulidae, is a severe pest of winter oilseed rape. A phenological model to forecast the first spring invasion of crops in Luxembourg by M. aeneus was developed in order to provide a tool for improving pest management and for assessing the potential effects of climate change on this pest. The model was derived using long-term, multi-site observational datasets of pollen beetle migration and meteorological data, as the timing of crop invasion is determined mainly by meteorological variables. Daily values of mean air and soil temperature, accumulated sunshine duration and precipitation were used to create a threshold-based model to forecast crop invasion. Minimising of the root mean squared error (RMSE of predicted versus observed migration dates was used as the quality criterion for selecting the optimum combination of threshold values for meteorological variables. We identified mean air temperature 8.0 °C, mean soil temperature 4.6 °C, and sunshine duration of 3.4 h as the best threshold values, with a cut-off of 1 mm precipitation and with no need for persistence of those conditions for more than one day (RMSE=9.3days$RMSE=9.3\\,\\text{days}$. Only in six out of 30 cases, differences between observed and predicted immigration dates were >5$>5$ days. In the future, crop invasion by pollen beetles will probably be strongly affected by changes in air temperature and precipitation related to climate change. We used a multi-model ensemble of 15 regional climate models driven by the A1B emission scenario to assess meteorological changes in two 30‑year future periods, near future (2021–2050 and far future (2069–2098 in comparison with the reference period (1971–2000. Air temperature and precipitation were predicted to increase in the first three months of each year, both in the near future and the far future. The pollen beetle migration model indicated that this change would

  1. Biomimetic Dye Aggregate Solar Cells

    OpenAIRE

    Marek, Peter L.

    2012-01-01

    A biomimetic self-assembling dye, which forms aggregates that mimic the natural light-harvesting system of special photosynthetic active bacteria, has been investigated towards its applicability to solar cells. This fully synthetic dye, self-assembles to orderly structured nano- to micrometer sized rod-shaped aggregates, which might improve solar cells based on conventional organic dyes. In order to use the full potential of the dye aggregates, the self-assembly needed to be controlled and a ...

  2. Aggregation in Large Dynamic Panels

    OpenAIRE

    Pesaran, Mohammad Hashem; Chudik, Alexander

    2011-01-01

    This paper considers the problem of aggregation in the case of large linear dynamic panels, where each micro unit is potentially related to all other micro units, and where micro innovations are allowed to be cross sectionally dependent. Following Pesaran (2003), an optimal aggregate function is derived, and the limiting behavior of the aggregation error is investigated as N (the number of cross section units) increases. Certain distributional features of micro parameters are also identi...

  3. Modifiers of mutant huntingtin aggregation

    OpenAIRE

    Teuling, Eva; Bourgonje, Annika; Veenje, Sven; Thijssen, Karen; Boer, Jelle de; van der Velde, Joeri; Swertz, Morris; Nollen, Ellen

    2011-01-01

    Protein aggregation is a common hallmark of a number of age-related neurodegenerative diseases, including Alzheimer’s, Parkinson’s, and polyglutamine-expansion disorders such as Huntington’s disease, but how aggregation-prone proteins lead to pathology is not known. Using a genome-wide RNAi screen in a C. elegans-model for polyglutamine aggregation, we previously identified 186 genes that suppress aggregation. Using an RNAi screen for human orthologs of these genes, we here present 26 human g...

  4. Aggregation dynamics of rigid polyelectrolytes

    Science.gov (United States)

    Tom, Anvy Moly; Rajesh, R.; Vemparala, Satyavani

    2016-01-01

    Similarly charged polyelectrolytes are known to attract each other and aggregate into bundles when the charge density of the polymers exceeds a critical value that depends on the valency of the counterions. The dynamics of aggregation of such rigid polyelectrolytes are studied using large scale molecular dynamics simulations. We find that the morphology of the aggregates depends on the value of the charge density of the polymers. For values close to the critical value, the shape of the aggregates is cylindrical with height equal to the length of a single polyelectrolyte chain. However, for larger values of charge, the linear extent of the aggregates increases as more and more polymers aggregate. In both the cases, we show that the number of aggregates decrease with time as power laws with exponents that are not numerically distinguishable from each other and are independent of charge density of the polymers, valency of the counterions, density, and length of the polyelectrolyte chain. We model the aggregation dynamics using the Smoluchowski coagulation equation with kernels determined from the molecular dynamics simulations and justify the numerically obtained value of the exponent. Our results suggest that once counterions condense, effective interactions between polyelectrolyte chains short-ranged and the aggregation of polyelectrolytes are diffusion-limited.

  5. Novel aspects of platelet aggregation

    Directory of Open Access Journals (Sweden)

    Roka-Moya Y. M.

    2014-01-01

    Full Text Available The platelet aggregation is an important process, which is critical for the hemostatic plug formation and thrombosis. Recent studies have shown that the platelet aggregation is more complex and dynamic than it was previously thought. There are several mechanisms that can initiate the platelet aggregation and each of them operates under specific conditions in vivo. At the same time, the influence of certain plasma proteins on this process should be considered. This review intends to summarize the recent data concerning the adhesive molecules and their receptors, which provide the platelet aggregation under different conditions.

  6. An illustrated checklist of dung beetles (Coleoptera: Scarabaeinae from the Periyar Tiger Reserve, Kerala, India

    Directory of Open Access Journals (Sweden)

    Nithya Sathiandran

    2015-12-01

    Full Text Available An illustrated checklist of 36 species of dung beetles (Coleoptera: Scarabaeinae from the Periyar Tiger Reserve in the southern Western Ghats is presented.  Records of eight species endemic to the Western Ghats and a rare primitive old world dung beetle group, Ochicanthon nitidus (Paulian, from the forests of Periyar Tiger Reserve are provided. 

  7. Traditional African plant products to protect stored cowpeas against insect damage : the battle against the beetle

    NARCIS (Netherlands)

    Boeke, S.J.

    2002-01-01

    Seeds of the cowpea plant, Vigna unguiculata , a tropical crop, are very susceptible to attack by the cowpea beetle. This specialist beetle needs only the beans to reproduce rapidly.Most farmers in West Africa have few possibilities to treat the beans and they face their stored supply

  8. Semiochemical based attraction of Small Hive Beetle: a window into evolution and invasive biology

    Science.gov (United States)

    Insect behavioral preferences are tied to individual experience and evolutionary history. The Small hive beetle, Aethina tumida, is seemingly an anomaly among Nitidulids because members of the genus commonly feed on fruit and decaying material in association with fungi but the small hive beetle th...

  9. Platelet aggregation following trauma

    DEFF Research Database (Denmark)

    Windeløv, Nis A; Sørensen, Anne M; Perner, Anders;

    2014-01-01

    We aimed to elucidate platelet function in trauma patients, as it is pivotal for hemostasis yet remains scarcely investigated in this population. We conducted a prospective observational study of platelet aggregation capacity in 213 adult trauma patients on admission to an emergency department (ED......). Inclusion criteria were trauma team activation and arterial cannula insertion on arrival. Blood samples were analyzed by multiple electrode aggregometry initiated by thrombin receptor agonist peptide 6 (TRAP) or collagen using a Multiplate device. Blood was sampled median 65 min after injury; median injury...... severity score (ISS) was 17; 14 (7%) patients received 10 or more units of red blood cells in the ED (massive transfusion); 24 (11%) patients died within 28 days of trauma: 17 due to cerebral injuries, four due to exsanguination, and three from other causes. No significant association was found between...

  10. Fractal Aggregation Under Rotation

    Institute of Scientific and Technical Information of China (English)

    WUFeng-Min; WULi-Li; LUHang-Jun; LIQiao-Wen; YEGao-Xiang

    2004-01-01

    By means of the Monte Carlo simulation, a fractal growth model is introduced to describe diffusion-limited aggregation (DLA) under rotation. Patterns which are different from the classical DLA model are observed and the fractal dimension of such clusters is calculated. It is found that the pattern of the clusters and their fractal dimension depend strongly on the rotation velocity of the diffusing particle. Our results indicate the transition from fractal to non-fractal behavior of growing cluster with increasing rotation velocity, i.e. for small enough angular velocity ω; thefractal dimension decreases with increasing ω;, but then, with increasing rotation velocity, the fractal dimension increases and the cluster becomes compact and tends to non-fractal.

  11. Fractal Aggregation Under Rotation

    Institute of Scientific and Technical Information of China (English)

    WU Feng-Min; WU Li-Li; LU Hang-Jun; LI Qiao-Wen; YE Gao-Xiang

    2004-01-01

    By means of the Monte Carlo simulation, a fractal growth model is introduced to describe diffusion-limited aggregation (DLA) under rotation. Patterns which are different from the classical DLA model are observed and the fractal dimension of such clusters is calculated. It is found that the pattern of the clusters and their fractal dimension depend strongly on the rotation velocity of the diffusing particle. Our results indicate the transition from fractal to non-fractal behavior of growing cluster with increasing rotation velocity, i.e. for small enough angular velocity ω the fractal dimension decreases with increasing ω, but then, with increasing rotation velocity, the fractal dimension increases and the cluster becomes compact and tends to non-fractal.

  12. Production of lightweight aggregate from industrial waste and carbon dioxide.

    Science.gov (United States)

    Gunning, Peter J; Hills, Colin D; Carey, Paula J

    2009-10-01

    The concomitant recycling of waste and carbon dioxide emissions is the subject of developing technology designed to close the industrial process loop and facilitate the bulk-re-use of waste in, for example, construction. The present work discusses a treatment step that employs accelerated carbonation to convert gaseous carbon dioxide into solid calcium carbonate through a reaction with industrial thermal residues. Treatment by accelerated carbonation enabled a synthetic aggregate to be made from thermal residues and waste quarry fines. The aggregates produced had a bulk density below 1000 kg/m(3) and a high water absorption capacity. Aggregate crushing strengths were between 30% and 90% stronger than the proprietary lightweight expanded clay aggregate available in the UK. Cast concrete blocks containing the carbonated aggregate achieve compressive strengths of 24 MPa, making them suitable for use with concrete exposed to non-aggressive service environments. The energy intensive firing and sintering processes traditionally required to produce lightweight aggregates can now be augmented by a cold-bonding, low energy method that contributes to the reduction of green house gases to the atmosphere. PMID:19577916

  13. Research on Judgment Aggregation Based on Logic

    OpenAIRE

    Li Dai; Jihua Zhang

    2014-01-01

    Preference aggregation and judgment aggregation are two basic research models of group decision making. And preference aggregation has been deeply studied in social choice theory. However, researches of social choice theory gradually focus on judgment aggregation which appears recently. Judgment aggregation focuses on how to aggregate many consistent logical formulas into one, from the perspective of logic. We try to start with judgment aggregation model based on logic and then explore differ...

  14. Facilitative root interactions in intercrops

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, H.; Jensen, E.S.

    2005-01-01

    Facilitation takes place when plants ameliorate the environment of their neighbours, and increase their growth and survival. Facilitation occurs in natural ecosystems as well as in agroecosystems. We discuss examples of facilitative root interactions in intercropped agroecosystems; including...... root architecture, exudation of growth stimulating substances, and biofumigation. Facilitative root interactions are most likely to be of importance in nutrient poor soils and in low-input agroecosystems due to critical interspecific competition for plant growth factors. However, studies from more...

  15. Click beetle luciferases as dual reporters of gene expression in Candida albicans.

    Science.gov (United States)

    Kapitan, Mario; Eichhof, Isabel; Lagadec, Quentin; Ernst, Joachim F

    2016-08-01

    Synthetic genes encoding functional luciferases of the click beetle (CB) Pyrophorus plagiophthalamus have been expressed in the human fungal pathogen Candida albicans. Both green- and red-emitting CB luciferases (CaCBGluc and CaCBRluc) were produced with high efficiency in transformants under transcriptional control of the growth-dependent ACT1 promoter, as well as by the HWP1 and UME6 promoters, which are upregulated during hyphal morphogenesis, as well as by the YWP1 and EFG1 promoters, which are downregulated. For all hyphally regulated genes, relative bioluminescence values derived from promoter fusions approximated relative transcript levels of native genes, although downregulation of YWP1 promoter activity required correction for the stability of CB luciferases (approximate half-lives 30 min for CaCBRluc and 80 min for CaCBGluc, as determined by immunoblotting). Importantly, the activity of both luciferases could be separately monitored in a single strain, in intact cells, in lysed cells or in cell extracts using luciferin as single substrate and inhibition of hypha formation by farnesol could be easily detected by the HWP1p-CaCBRluc fusion. The results suggest that CB luciferases are convenient tools to measure gene expression in C. albicans and may facilitate screenings for antifungal compounds. PMID:27339610

  16. Topics in Probabilistic Judgment Aggregation

    Science.gov (United States)

    Wang, Guanchun

    2011-01-01

    This dissertation is a compilation of several studies that are united by their relevance to probabilistic judgment aggregation. In the face of complex and uncertain events, panels of judges are frequently consulted to provide probabilistic forecasts, and aggregation of such estimates in groups often yield better results than could have been made…

  17. J-aggregates, v.2

    CERN Document Server

    Kobayashi, Takayoshi

    2012-01-01

    This work deals with J-aggregates, which have a long history of research. The volume covers electronic states, linear and nonlinear optical properties. Various properties and processes of J-aggregates, such as super-radiance, excitons, photon echo, geometrical structure, electron transfer and femtosecond spectroscopy, are discussed.

  18. Molecular aggregation of humic substances

    Science.gov (United States)

    Wershaw, R. L.

    1999-01-01

    Humic substances (HS) form molecular aggregates in solution and on mineral surfaces. Elucidation of the mechanism of formation of these aggregates is important for an understanding of the interactions of HS in soils arid natural waters. The HS are formed mainly by enzymatic depolymerization and oxidation of plant biopolymers. These reactions transform the aromatic and lipid plant components into amphiphilic molecules, that is, molecules that consist of separate hydrophobic (nonpolar) and hydrophilic (polar) parts. The nonpolar parts of the molecules are composed of relatively unaltered segments of plant polymers and the polar parts of carboxylic acid groups. These amphiphiles form membrane-like aggregates on mineral surfaces and micelle-like aggregates in solution. The exterior surfaces of these aggregates are hydrophilic, and the interiors constitute separate hydrophobic liquid-like phases.

  19. Immunogenicity of Therapeutic Protein Aggregates.

    Science.gov (United States)

    Moussa, Ehab M; Panchal, Jainik P; Moorthy, Balakrishnan S; Blum, Janice S; Joubert, Marisa K; Narhi, Linda O; Topp, Elizabeth M

    2016-02-01

    Therapeutic proteins have a propensity for aggregation during manufacturing, shipping, and storage. The presence of aggregates in protein drug products can induce adverse immune responses in patients that may affect safety and efficacy, and so it is of concern to both manufacturers and regulatory agencies. In this vein, there is a lack of understanding of the physicochemical determinants of immunological responses and a lack of standardized analytical methods to survey the molecular properties of aggregates associated with immune activation. In this review, we provide an overview of the basic immune mechanisms in the context of interactions with protein aggregates. We then critically examine the literature with emphasis on the underlying immune mechanisms as they relate to aggregate properties. Finally, we highlight the gaps in our current understanding of this issue and offer recommendations for future research. PMID:26869409

  20. DRAG ON SUBMICRON NANOPARTICLE AGGREGATES

    Institute of Scientific and Technical Information of China (English)

    F.; Einar; Kruis

    2005-01-01

    A new procedure was developed for estimating the effective collision diameter of an aggregate composed of primary particles of any size. The coagulation coefficient of two oppositely charged particles was measured experimentally and compared with classic Fuchs theory, including a new method to account for particle non-sphericity. A second set of experiments were performed on well-defined nanoparticle aggregates at different stages of sintering, i.e. from the aggregate to the fully sintered stage. Here, electrical mobility was used to characterize the particle drag. The aggregates are being built from two different size-fractionated nanoparticle aerosols, the non-aggregated particles are discarded by an electrofilter and then they are passed through a furnace at concentrations low enough not to induce coagulation.

  1. Mechanics of fire ant aggregations

    Science.gov (United States)

    Tennenbaum, Michael; Liu, Zhongyang; Hu, David; Fernandez-Nieves, Alberto

    2016-01-01

    Fire ants link their bodies to form aggregations; these can adopt a variety of structures, they can drip and spread, or withstand applied loads. Here, by using oscillatory rheology, we show that fire ant aggregations are viscoelastic. We find that, at the lowest ant densities probed and in the linear regime, the elastic and viscous moduli are essentially identical over the spanned frequency range, which highlights the absence of a dominant mode of structural relaxation. As ant density increases, the elastic modulus rises, which we interpret by alluding to ant crowding and subsequent jamming. When deformed beyond the linear regime, the aggregation flows, exhibiting shear-thinning behaviour with a stress load that is comparable to the maximum load the aggregation can withstand before individual ants are torn apart. Our findings illustrate the rich, collective mechanical behaviour that can arise in aggregations of active, interacting building blocks.

  2. Erythrocyte aggregation in flowing blood

    International Nuclear Information System (INIS)

    This paper addresses the issue of whether nonionic contrast media (CM) promote thrombosis by the formation of large, irregular red blood cell aggregates with videomicroscopy and a flow chamber, red blood cell aggregates adjacent to an endothelial cell monolayer were imaged at 17 sec-1 in dilute suspensions (hematocrit, --8) at 370C in plasma with 20% CM by non-red blood cell volume. All aggregates were rouleaux (<100 μm) readily dispersed at higher shear rates. Aggregate length in eight experiments was increased 11% by ioxaglate (320 mg of iodine per milliliter), decreased 58% by diatrizoate (370 mg of iodine per milliliter) but reduced similarly (16%) by iohexol (350 mg of iodine per milliliter) and saline. Iohexol did not enhance platelet aggregation on injured monolayers

  3. RankAggreg, an R package for weighted rank aggregation

    Directory of Open Access Journals (Sweden)

    Datta Susmita

    2009-02-01

    Full Text Available Abstract Background Researchers in the field of bioinformatics often face a challenge of combining several ordered lists in a proper and efficient manner. Rank aggregation techniques offer a general and flexible framework that allows one to objectively perform the necessary aggregation. With the rapid growth of high-throughput genomic and proteomic studies, the potential utility of rank aggregation in the context of meta-analysis becomes even more apparent. One of the major strengths of rank-based aggregation is the ability to combine lists coming from different sources and platforms, for example different microarray chips, which may or may not be directly comparable otherwise. Results The RankAggreg package provides two methods for combining the ordered lists: the Cross-Entropy method and the Genetic Algorithm. Two examples of rank aggregation using the package are given in the manuscript: one in the context of clustering based on gene expression, and the other one in the context of meta-analysis of prostate cancer microarray experiments. Conclusion The two examples described in the manuscript clearly show the utility of the RankAggreg package in the current bioinformatics context where ordered lists are routinely produced as a result of modern high-throughput technologies.

  4. Facilitating post traumatic growth

    Directory of Open Access Journals (Sweden)

    Cox Helen

    2004-07-01

    Full Text Available Abstract Background Whilst negative responses to traumatic injury have been well documented in the literature, there is a small but growing body of work that identifies posttraumatic growth as a salient feature of this experience. We contribute to this discourse by reporting on the experiences of 13 individuals who were traumatically injured, had undergone extensive rehabilitation and were discharged from formal care. All participants were injured through involvement in a motor vehicle accident, with the exception of one, who was injured through falling off the roof of a house. Methods In this qualitative study, we used an audio-taped in-depth interview with each participant as the means of data collection. Interviews were transcribed verbatim and analysed thematically to determine the participants' unique perspectives on the experience of recovery from traumatic injury. In reporting the findings, all participants' were given a pseudonym to assure their anonymity. Results Most participants indicated that their involvement in a traumatic occurrence was a springboard for growth that enabled them to develop new perspectives on life and living. Conclusion There are a number of contributions that health providers may make to the recovery of individuals who have been traumatically injured to assist them to develop new views of vulnerability and strength, make changes in relationships, and facilitate philosophical, physical and spiritual growth.

  5. Adult beetles compensate for poor larval food conditions.

    Science.gov (United States)

    Müller, Thorben; Müller, Caroline

    2016-05-01

    Life history traits of herbivores are highly influenced by the quality of their hosts, i.e., the composition of primary and secondary plant metabolites. In holometabolous insects, larvae and adults may face different host plants, which differ in quality. It has been hypothesised that adult fitness is either highest when larval and adult environmental conditions match (environmental matching) or it may be mainly determined by optimal larval conditions (silver spoon effect). Alternatively, the adult stage may be most decisive for the actual fitness, independent of larval food exposure, due to adult compensation ability. To determine the influence of constant versus changing larval and adult host plant experiences on growth performance, fitness and feeding preferences, we carried out a match-mismatch experiment using the mustard leaf beetle, Phaedon cochleariae. Larvae and adults were either constantly reared on watercress (natural host) or cabbage (crop plant) or were switched after metamorphosis to the other host. Growth, reproductive traits and feeding preferences were determined repeatedly over lifetime and host plant quality traits analysed. Differences in the host quality led to differences in the development time and female reproduction. Egg numbers were significantly influenced by the host plant species experienced by the adults. Thus, adults were able to compensate for poor larval conditions. Likewise, the current host experience was most decisive for feeding preferences; in adult beetles a feeding preference was shaped regardless of the larval host plant. Larvae or adults reared on the more nutritious host, cabbage, showed a higher preference for this host. Hence, beetles most likely develop a preference when gaining a direct positive feedback in terms of an improved performance, whereby the current experience matters the most. Highly nutritious crop plants may be, in consequence, all the more exploited by potential pests that may show a high plasticity in

  6. Perspectives on Preference Aggregation.

    Science.gov (United States)

    Regenwetter, Michel

    2009-07-01

    For centuries, the mathematical aggregation of preferences by groups, organizations, or society itself has received keen interdisciplinary attention. Extensive theoretical work in economics and political science throughout the second half of the 20th century has highlighted the idea that competing notions of rational social choice intrinsically contradict each other. This has led some researchers to consider coherent democratic decision making to be a mathematical impossibility. Recent empirical work in psychology qualifies that view. This nontechnical review sketches a quantitative research paradigm for the behavioral investigation of mathematical social choice rules on real ballots, experimental choices, or attitudinal survey data. The article poses a series of open questions. Some classical work sometimes makes assumptions about voter preferences that are descriptively invalid. Do such technical assumptions lead the theory astray? How can empirical work inform the formulation of meaningful theoretical primitives? Classical "impossibility results" leverage the fact that certain desirable mathematical properties logically cannot hold in all conceivable electorates. Do these properties nonetheless hold true in empirical distributions of preferences? Will future behavioral analyses continue to contradict the expectations of established theory? Under what conditions do competing consensus methods yield identical outcomes and why do they do so? PMID:26158988

  7. Surveying an endangered saproxylic beetle, Osmoderma eremita, in Mediterranean woodlands

    DEFF Research Database (Denmark)

    Chiari, Stefano; Zauli, Agnese; Mazziotta, Adriano;

    2013-01-01

    Measuring population size is riddled with difficulties for wildlife biologists and managers, and in the case of rare species, it is sometimes practically impossible to estimate abundance, whereas estimation of occupancy is possible. Furthermore, obtaining reliable population size estimates is not....... Detection probability and population size estimates were drawn from each of these four capture methods. There were strong differences in detection probability among methods. Despite using pheromone and beetle manipulation, capture histories were not affected by trap-happiness or trap-shyness. Population...

  8. Cellular Concrete Bricks with Recycled Expanded Polystyrene Aggregate

    OpenAIRE

    Juan Bosco Hernández-Zaragoza; Teresa López-Lara; Jaime Horta-Rangel; Carlos López-Cajún; Eduardo Rojas-González; F. J. García-Rodríguez; Jorge Adue

    2013-01-01

    Cellular concrete bricks were obtained by using a lightweight mortar with recycled expanded polystyrene aggregate instead of sandy materials. After determining the block properties (absorption, compressive strength, and tensile stresses), it was found that this brick meets the requirements of the masonry standards used in Mexico. The obtained material is lighter than the commercial ones, which facilitates their rapid elaboration, quality control, and transportation. It is less permeable, whic...

  9. Quantitative metabolome, proteome and transcriptome analysis of midgut and fat body tissues in the mountain pine beetle, Dendroctonus ponderosae Hopkins, and insights into pheromone biosynthesis.

    Science.gov (United States)

    Keeling, Christopher I; Li, Maria; Sandhu, Harpreet K; Henderson, Hannah; Yuen, Macaire Man Saint; Bohlmann, Jörg

    2016-03-01

    Bark beetles (Coleoptera: Scolytinae) are pests of many forests around the world. The mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, is a significant pest of western North American pine forests. The MPB is able to overcome the defences of pine trees through pheromone-assisted aggregation that results in a mass attack of host trees. These pheromones, both male and female produced, are believed to be biosynthesized in the midgut and/or fat bodies of these insects. We used metabolite analysis, quantitative proteomics (iTRAQ) and transcriptomics (RNA-seq) to identify proteins and transcripts differentially expressed between sexes and between tissues when treated with juvenile hormone III. Juvenile hormone III induced frontalin biosynthesis in males and trans-verbenol biosynthesis in females, as well as affected the expression of many proteins and transcripts in sex- and tissue-specific ways. Based on these analyses, we identified candidate genes involved in the biosynthesis of frontalin, exo-brevicomin, and trans-verbenol pheromones. PMID:26792242

  10. Management of Chinese Rose Beetle (Adoretus sinicus) Adults Feeding on Cacao (Theobroma cacao) Using Insecticides.

    Science.gov (United States)

    Spafford, Helen; Ching, Alexander; Manley, Megan; Hardin, Chelsea; Bittenbender, Harry

    2016-01-01

    The Chinese rose beetle (Adoretus sinicus Burmeister (Coleoptera: Scarabaeidae)) is an introduced, widely-established pest in Hawai'i. The adult beetles feed on the leaves of cacao (Theobroma cacao L.), which can lead to defoliation and even death of young trees. We evaluated the impact of five commercially available products with different active ingredients (imidacloprid, azadirachtin, Beauveria bassiana (Bals.-Criv.) Vuill., kaolin clay, and pyrethrin) and the presence or absence of weed mat cover in reducing adult beetle feeding on sapling cacao in the field. The use of weed mat cover reduced feeding damage compared to the untreated control, as did foliar application of imidacloprid, azadirachtin, and B. bassiana. In the laboratory, field-collected adult beetles were presented cacao leaf samples dipped in one of the five products and compared to a control. Beetles exposed to pyrethrin died rapidly. Among the other treatments, only exposure to imidacloprid significantly reduced survival relative to the control. Beetles fed very little on leaf samples with azadirachtin but their longevity was not significantly reduced. Imidacloprid, azadirachtin, and weed mat application had the most promise for reducing adult Chinese rose beetle feeding damage in young cacao and deserve further investigation for successful management of this significant pest. PMID:27348004

  11. Landscape-scale analysis of aboveground tree carbon stocks affected by mountain pine beetles in Idaho

    Science.gov (United States)

    Bright, B. C.; Hicke, J. A.; Hudak, A. T.

    2012-12-01

    Bark beetle outbreaks kill billions of trees in western North America, and the resulting tree mortality can significantly impact local and regional carbon cycling. However, substantial variability in mortality occurs within outbreak areas. Our objective was to quantify landscape-scale effects of beetle infestations on aboveground carbon (AGC) stocks using field observations and remotely sensed data across a 5054 ha study area that had experienced a mountain pine beetle outbreak. Tree mortality was classified using multispectral imagery that separated green, red, and gray trees, and models relating field observations of AGC to LiDAR data were used to map AGC. We combined mortality and AGC maps to quantify AGC in beetle-killed trees. Thirty-nine per cent of the forested area was killed by beetles, with large spatial variability in mortality severity. For the entire study area, 40-50% of AGC was contained in beetle-killed trees. When considered on a per-hectare basis, 75-89% of the study area had >25% AGC in killed trees and 3-6% of the study area had >75% of the AGC in killed trees. Our results show that despite high variability in tree mortality within an outbreak area, bark beetle epidemics can have a large impact on AGC stocks at the landscape scale.

  12. Landscape-scale analysis of aboveground tree carbon stocks affected by mountain pine beetles in Idaho

    International Nuclear Information System (INIS)

    Bark beetle outbreaks kill billions of trees in western North America, and the resulting tree mortality can significantly impact local and regional carbon cycling. However, substantial variability in mortality occurs within outbreak areas. Our objective was to quantify landscape-scale effects of beetle infestations on aboveground carbon (AGC) stocks using field observations and remotely sensed data across a 5054 ha study area that had experienced a mountain pine beetle outbreak. Tree mortality was classified using multispectral imagery that separated green, red, and gray trees, and models relating field observations of AGC to LiDAR data were used to map AGC. We combined mortality and AGC maps to quantify AGC in beetle-killed trees. Thirty-nine per cent of the forested area was killed by beetles, with large spatial variability in mortality severity. For the entire study area, 40–50% of AGC was contained in beetle-killed trees. When considered on a per-hectare basis, 75–89% of the study area had >25% AGC in killed trees and 3–6% of the study area had >75% of the AGC in killed trees. Our results show that despite high variability in tree mortality within an outbreak area, bark beetle epidemics can have a large impact on AGC stocks at the landscape scale. (letter)

  13. Dung beetles (Coleoptera, Scarabaeinae attracted to sheep dung in exotic pastures

    Directory of Open Access Journals (Sweden)

    César Murilo de Albuquerque Correa

    2013-03-01

    Full Text Available Dung beetles (Coleoptera, Scarabaeinae attracted to sheep dung in exotic pastures. In this study we provide data on the abundance and richness of dung beetles (Coleoptera, Scarabaeidae, Scarabaeinae attracted to sheep dung in exotic pastures (Brachiaria spp.. In four areas of exotic pasture pitfall traps were installed and baited with fresh sheep dung for sampling of dung beetles. A total of 2,290 individuals were captured belonging to 16 species, 10 genera and five tribes of Scarabaeinae beetles. Trichillum externepunctatum Preudhomme de Borre, 1886 and Dichotomius bos (Blanchard, 1843 were dominant. The guild of dwellers was the most abundant in pastures. We demonstrate that dung beetles are attracted to sheep dung. Since the production of both cattle and sheep in the same area is common in tropical pasturelands, results obtained here highlight the need to investigate the actual role of dung sharing (cattle dung + sheep dung by dung beetles. It is also suggested that experiments be performed for evaluation of the ecological functions performed by dung beetles using sheep dung.

  14. Tropical rain forest fragmentation, howler monkeys (Alouatta palliata), and dung beetles at Los Tuxtlas, Mexico.

    Science.gov (United States)

    Estrada, A; Anzures D, A; Coates-Estrada, R

    1999-01-01

    In Neotropical rain forests, fresh mammal dung, especially that of howler monkeys, constitutes an important resource used by dung beetles as food and for oviposition and further feeding by their larvae. Tropical rain forest destruction, fragmentation, and subsequent isolation causing reductions in numbers of and the disappearance of howler monkeys may result in decreasing numbers of dung beetles, but this has not been documented. In this study, we present information on the presence of howlers and dung beetles in 38 isolated forest fragments and 15 agricultural habitats. Howler monkeys were censused by visual means, while dung beetles were sampled with traps baited with a mixture of howler, cow, horse, and dog dung. Results indicated that loss of area and isolation of forest fragments result in significant decrements in howlers and dung beetles. However, dung beetle abundance was found to be closely related to the presence of howler monkeys at the sites and habitats investigated. Scenarios of land management designed to reduce isolation among forest fragments may help sustain populations of howler monkeys and dung beetles, which may have positive consequences for rain forest regeneration. PMID:10402034

  15. Reflective Polyethylene Mulch Reduces Mexican Bean Beetle (Coleoptera: Coccinellidae) Densities and Damage in Snap Beans.

    Science.gov (United States)

    Nottingham, L B; Kuhar, T P

    2016-08-01

    Mexican bean beetle, Epilachna varivestis Mulsant, is a serious pest of snap beans, Phaseolus vulgaris L., in the eastern United States. These beetles are intolerant to direct sunlight, explaining why individuals are typically found on the undersides of leaves and in the lower portion of the plant canopy. We hypothesized that snap beans grown on reflective, agricultural polyethylene (plastic mulch) would have fewer Mexican bean beetles and less injury than those grown on black plastic or bare soil. In 2014 and 2015, beans were seeded into beds of metallized, white, and black plastic, and bare soil, in field plots near Blacksburg, VA. Mexican bean beetle density, feeding injury, predatory arthropods, and snap bean yield were sampled. Reflected light intensity, temperature, and humidity were monitored using data loggers. Pyranometer readings showed that reflected light intensity was highest over metallized plastic and second highest over white plastic; black plastic and bare soil were similarly low. Temperature and humidity were unaffected by treatments. Significant reductions in Mexican bean beetle densities and feeding injury were observed in both metallized and white plastic plots compared to black plastic and bare soil, with metallized plastic having the fewest Mexican bean beetle life stages and injury. Predatory arthropod densities were not reduced by reflective plastic. Metallized plots produced the highest yields, followed by white. The results of this study suggest that growing snap beans on reflective plastic mulch can suppress the incidence and damage of Mexican bean beetle, and increase yield in snap beans. PMID:27341891

  16. Ophiostoma species (Ascomycetes: Ophiostomatales) associated with bark beetles (Coleoptera: Scolytinae) colonizing Pinus radiata in northern Spain.

    Science.gov (United States)

    Romón, Pedro; Zhou, XuDong; Iturrondobeitia, Juan Carlos; Wingfield, Michael J; Goldarazena, Arturo

    2007-06-01

    Bark beetles (Coleoptera: Scolytinae) are known to be associated with fungi, especially species of Ophiostoma sensu lato and Ceratocystis. However, very little is known about these fungi in Spain. In this study, we examined the fungi associated with 13 bark beetle species and one weevil (Coleoptera: Entiminae) infesting Pinus radiata in the Basque Country of northern Spain. This study included an examination of 1323 bark beetles or their galleries in P. radiata. Isolations yielded a total of 920 cultures, which included 16 species of Ophiostoma sensu lato or their asexual states. These 16 species included 69 associations between fungi and bark beetles and weevils that have not previously been recorded. The most commonly encountered fungal associates of the bark beetles were Ophiostoma ips, Leptographium guttulatum, Ophiostoma stenoceras, and Ophiostoma piceae. In most cases, the niche of colonization had a significant effect on the abundance and composition of colonizing fungi. This confirms that resource overlap between species is reduced by partial spatial segregation. Interaction between niche and time seldom had a significant effect, which suggests that spatial colonization patterns are rarely flexible throughout timber degradation. The differences in common associates among the bark beetle species could be linked to the different niches that these beetles occupy. PMID:17668036

  17. Using dung beetles to evaluate the effects of urbanization on Atlantic Forest biodiversity

    Institute of Scientific and Technical Information of China (English)

    Vanesca Korasaki; José Lopes; George Gardner Brown; Julio Louzada

    2013-01-01

    We used dung beetles to evaluate the impact of urbanization on insect biodiversity in three Atlantic Forest fragments in Londrina,Paraná,Brazil.This study provides the first empirical evidence of the impact of urbanization on richness,abundance,composition and guild structure of dung beetle communities from the Brazilian Atlantic Forest.We evaluated the community aspects (abundance,richness,composition and food guilds) of dung beetles in fragments with different degrees of immersion in the urban matrix using pitfall traps with four alternative baits (rotten meat,rotten fish,pig dung and decaying banana).A total of 1719 individuals were collected,belonging to 29 species from 11 genera and six Scarabaeinae tribes.The most urban-immersed fragment showed a higher species dominance and the beetle community captured on dung presented the greatest evenness.The beetle communities were distinct with respect to the fragments and feeding habits.Except for the dung beetle assemblage in the most urbanized forest fragment,all others exhibited contrasting differences in species composition attracted to each bait type.Our results clearly show that the degree of urbanization affects Atlantic Forest dung beetle communities and that the preservation of forest fragments inside the cities,even small ones,can provide refuges for Scarabaeinae.

  18. Behavioral niche partitioning in a sympatric tiger beetle assemblage and implications for the endangered Salt Creek tiger beetle

    Directory of Open Access Journals (Sweden)

    Tierney R. Brosius

    2013-09-01

    Full Text Available How behavioral patterns are related to niche partitioning is an important question in understanding how closely related species within ecological communities function. Behavioral niche partitioning associated with thermoregulation is well documented in tiger beetles as a group. Co-occurring species of salt flat tiger beetles have adapted many thermoregulatory behaviors to cope with this harsh ecosystem. On first examination these beetles appear to occur in overlapping microhabitats and therefore compete for resources. To determine if behavioral niche partitioning is allowing multiple species to occur within the same harsh salt flat ecosystem we observed Cicindela nevadica lincolniana, Cicindela circumpicta, Cicindela fulgida, and Cicindela togata between 8:00 h and 21:00 h and recorded all behaviors related to thermoregulation using a digital voice recorder. Results of this study strongly indicate that competition among these species for resources has been reduced by the adaptation of different thermoregulatory behaviors such as spending time in shallow water, avoiding the sun during the hottest parts of the day, and by positioning their body against or away from the soil. The endangered C. n. lincolniana appears to rely most heavily on the shallow water of seeps for their diurnal foraging behavior (potentially limiting their foraging habitat, but with the advantage of allowing foraging during the hottest times of the day when potential competitors are less frequent. Ironically, this association also may help explain C. n. lincolniana’s susceptibility to extinction: beyond the loss of saline wetlands generally, limited seeps and pools even within remaining saline habitat may represent a further habitat limitation within an already limited habitat.

  19. Anonymous aggregator election and data aggregation in wireless sensor networks

    OpenAIRE

    Tamás Holczer; Levente Buttyán

    2011-01-01

    In mission critical cyber-physical systems, dependability is an important requirement at all layers of the system architecture. In this paper, we propose protocols that increase the dependability of wireless sensor networks, which are potentially useful building blocks in cyber-physical systems. More specifically, we propose two private aggregator node election protocols, a private data aggregation protocol, and a corresponding private query protocol for sensor networks that allow for secure ...

  20. Functional genomics of mountain pine beetle (Dendroctonus ponderosae midguts and fat bodies

    Directory of Open Access Journals (Sweden)

    Bearfield Jeremy C

    2010-03-01

    Full Text Available Abstract Background The mountain pine beetle (Dendroctonus ponderosae is a significant coniferous forest pest in western North America. It relies on aggregation pheromones to colonize hosts. Its three major pheromone components, trans-verbenol, exo-brevicomin, and frontalin, are thought to arise via different metabolic pathways, but the enzymes involved have not been identified or characterized. We produced ESTs from male and female midguts and associated fat bodies and used custom oligonucleotide microarrays to study gene expression patterns and thereby made preliminary identification of pheromone-biosynthetic genes. Results Clones from two un-normalized cDNA libraries were directionally sequenced from the 5' end to yield 11,775 ESTs following sequence cleansing. The average read length was 550 nt. The ESTs clustered into 1,201 contigs and 2,833 singlets (4,034 tentative unique genes. The ESTs are broadly distributed among GO functional groups, suggesting they reflect a broad spectrum of the transcriptome. Among the most represented genes are representatives of sugar-digesting enzymes and members of an apparently Scolytid-specific gene family of unknown function. Custom NimbleGen 4-plex arrays representing the 4,034 tentative unique genes were queried with RNA from eleven different biological states representing larvae, pupae, and midguts and associated fat bodies of unfed or fed adults. Quantitative (Real-Time RT-PCR (qRT-PCR experiments confirmed that the microarray data accurately reflect expression levels in the different samples. Candidate genes encoding enzymes involved in terminal steps of biosynthetic pathways for exo-brevicomin and frontalin were tentatively identified. Conclusions These EST and microarray data are the first publicly-available functional genomics resources for this devastating forestry pest.

  1. The saproxylic beetle assemblage associated with different host trees in Southwest China

    Institute of Scientific and Technical Information of China (English)

    Jie Wu; Xiao-Dong Yu; Hong-Zhang Zhou

    2008-01-01

    Dead wood is a habitat for many insects and other small animals,some of which may be rare or endangered and in need of effective protection.In this paper,saproxylic beetle assemblages associated with different host trees in the subtropical forests in southwestern China were investigated.A total of 277 species (1 439 specimens) in 36 beetle families were collected from 117 dead wood samples,of which 101 samples were identified and respectively belonged to 12 tree genera.The number of saproxylic beetle species varied greatly among logs of different tree genera,with the highest diversity on logs of Juglans.Generally,broad-leaved trees had a higher richness and abundance of saproxylic species than coniferous trees.Cluster analysis revealed that assemblages from broad-leaved tree genera were generally similar (except for Betula) and assemblages from coniferous trees formed another distinct cluster.The subsequent indicator analysis proposed that there are different characteristic species for different cluster groups of host tree genera.In our study,log diameter has no positive influence on beetle species density.Conversely,comparisons of individual-based rarefaction curves suggested that beetle species richness was highest in the small diameter class both in coniferous and broad-leaved tree genera.With increased wood decay,proportion of habitat specialists (saproxylic beetles living on one tree genus)decreased,whereas proportion of habitat generalists (living on more than three tree genera)increased.The beetle species density was found to be higher in early stages,and decreased in later stages as well.A negative influence of altitude on saproxylic beetle species richness and abundance was detected.It was indicated that different tree genera and altitudes possibly display cross effects in modulating the altitudinal distribution and host preference of the beetles.

  2. Arrow’s theorem in judgment aggregation

    OpenAIRE

    Dietrich, Franz; List, Christian

    2005-01-01

    In response to recent work on the aggregation of individual judgments on logically connected propositions into collective judgments, it is often asked whether judgment aggregation is a special case of Arrowian preference aggregation. We argue for the converse claim. After proving two impossibility theorems on judgment aggregation (using “systematicity” and “independence” conditions, respectively), we construct an embedding of preference aggregation into judgment aggregation and prove Arrow’s ...

  3. Benefits of Dung Beetles (Coleoptera: Scarabaeidae) on Nutrient Cycling and Forage Growth in Alpaca Pastures

    OpenAIRE

    Arnaudin, Mary Elin

    2012-01-01

    Alpacas have been gaining prominence in the U.S. since the early 1980s. In pastures, dung beetle activity has been shown to enhance the degradation and incorporation of dung into the soil. The benefits of this activity have been quantified for cattle, but not for alpacas. The objectives of this study were to document the dung beetle species present in alpaca pastures, and to evaluate the impact of dung beetle activity on the growth of a common summer annual grass. In 2010 and 2011, dun...

  4. Significantly higher Carabid beetle (Coleoptera: Carabidae) catch in conventionally than in organically managed Christmas tree plantations

    DEFF Research Database (Denmark)

    Bagge, Søren; Lund, Malthe; Rønn, Regin;

    2012-01-01

    Carabid beetles play an important role as consumers of pest organisms in forestry and agriculture. Application of pesticides may negatively affect abundance and activity of carabid beetles, thus reducing their potential beneficial effect. We investigated how abundance and diversity of pitfall...... managed sites. Carabid beetle abundance and richness did not decline more between two sampling periods at sites with pesticide application than at unamended sites. Apparently, the amount of bare ground, which dominated in the conventionally managed, herbicide treated sites, correlated closely with the...

  5. Significantly Higher Carabid Beetle (Coleoptera: Carabidae) Catch in Conventionally than in Organically Managed Christmas Tree Plantations

    DEFF Research Database (Denmark)

    Bagge, Soren; Lund, Malthe; Ronn, Regin;

    2012-01-01

    Carabid beetles play an important role as consumers of pest organisms in forestry and agriculture. Application of pesticides may negatively affect abundance and activity of carabid beetles, thus reducing their potential beneficial effect. We investigated how abundance and diversity of pitfall...... managed sites. Carabid beetle abundance and richness did not decline more between two sampling periods at sites with pesticide application than at unamended sites. Apparently, the amount of bare ground, which dominated in the conventionally managed, herbicide treated sites, correlated closely with the...

  6. Hypogean carabid beetles as indicators of global warming?

    International Nuclear Information System (INIS)

    Climate change has been shown to impact the geographical and altitudinal distribution of animals and plants, and to especially affect range-restricted polar and mountaintop species. However, little is known about the impact on the relict lineages of cave animals. Ground beetles (carabids) show a wide variety of evolutionary pathways, from soil-surface (epigean) predatory habits to life in caves and in other subterranean (hypogean) compartments. We reconstructed an unprecedented set of species/time accumulation curves of the largest carabid genera in Europe, selected by their degree of ‘underground’ adaptation, from true epigean predators to eyeless highly specialized hypogean beetles. The data show that in recent periods an unexpectedly large number of new cave species were found lying in well established European hotspots; the first peak of new species, especially in the most evolved underground taxa, occurred in the 1920–30s and a second burst after the 70s. Temperature data show large warming rates in both periods, suggesting that the temperature increase in the past century might have induced cave species to expand their habitats into large well-aired cavities and superficial underground compartments, where they can be easily sampled. An alternative hypothesis, based on increased sampling intensity, is less supported by available datasets. (letter)

  7. Species radiation of carabid beetles (broscini: mecodema in new zealand.

    Directory of Open Access Journals (Sweden)

    Julia Goldberg

    Full Text Available New Zealand biodiversity has often been viewed as Gondwanan in origin and age, but it is increasingly apparent from molecular studies that diversification, and in many cases origination of lineages, postdate the break-up of Gondwanaland. Relatively few studies of New Zealand animal species radiations have as yet been reported, and here we consider the species-rich genus of carabid beetles, Mecodema. Constrained stratigraphic information (emergence of the Chatham Islands and a substitution rate for Coleoptera were separately used to calibrate Bayesian relaxed molecular clock date estimates for diversification of Mecodema. The inferred timings indicate radiation of these beetles no earlier than the mid-Miocene with most divergences being younger, dating to the Plio-Pleistocene. A shallow age for the radiation along with a complex spatial distribution of these taxa involving many instances of sympatry implicates recent ecological speciation rather than a simplistic allopatric model. This emphasises the youthful and dynamic nature of New Zealand evolution that will be further elucidated with detailed ecological and population genetic analyses.

  8. Hypogean carabid beetles as indicators of global warming?

    Science.gov (United States)

    Brandmayr, Pietro; Giorgi, Filippo; Casale, Achille; Colombetta, Giorgio; Mariotti, Laura; Vigna Taglianti, Augusto; Weber, Friedrich; Pizzolotto, Roberto

    2013-12-01

    Climate change has been shown to impact the geographical and altitudinal distribution of animals and plants, and to especially affect range-restricted polar and mountaintop species. However, little is known about the impact on the relict lineages of cave animals. Ground beetles (carabids) show a wide variety of evolutionary pathways, from soil-surface (epigean) predatory habits to life in caves and in other subterranean (hypogean) compartments. We reconstructed an unprecedented set of species/time accumulation curves of the largest carabid genera in Europe, selected by their degree of ‘underground’ adaptation, from true epigean predators to eyeless highly specialized hypogean beetles. The data show that in recent periods an unexpectedly large number of new cave species were found lying in well established European hotspots; the first peak of new species, especially in the most evolved underground taxa, occurred in the 1920-30s and a second burst after the 70s. Temperature data show large warming rates in both periods, suggesting that the temperature increase in the past century might have induced cave species to expand their habitats into large well-aired cavities and superficial underground compartments, where they can be easily sampled. An alternative hypothesis, based on increased sampling intensity, is less supported by available datasets.

  9. The Evolution of Functionally Redundant Species; Evidence from Beetles.

    Directory of Open Access Journals (Sweden)

    Marten Scheffer

    Full Text Available While species fulfill many different roles in ecosystems, it has been suggested that numerous species might actually share the same function in a near neutral way. So-far, however, it is unclear whether such functional redundancy really exists. We scrutinize this question using extensive data on the world's 4168 species of diving beetles. We show that across the globe these animals have evolved towards a small number of regularly-spaced body sizes, and that locally co-existing species are either very similar in size or differ by at least 35%. Surprisingly, intermediate size differences (10-20% are rare. As body-size strongly reflects functional aspects such as the food that these generalist predators can eat, these beetles thus form relatively distinct groups of functional look-a-likes. The striking global regularity of these patterns support the idea that a self-organizing process drives such species-rich groups to self-organize evolutionary into clusters where functional redundancy ensures resilience through an insurance effect.

  10. Effects of nitrogen application on beetle communities in tea plantations

    Institute of Scientific and Technical Information of China (English)

    Shao-Bo Chen; Zhi-Juan Wei; Zhao-Hua Zeng; Li-Lin Chen; Hui-Tao Chen; Min-Sheng You

    2009-01-01

    In contrast to grassland and forest ecosystems, little is known about insect response to nitrogen deposition in agricultural ecosystems. This study was carried out to investigate the effects of short-term (1-2 years) nitrogen application (0, 172.5, 345.0, 690.0, families, 89 species of beetles, was obtained from a tea plantation in Wuyishan, China. Among them, herbivores, predators and detritivores had 52, 29, and eight species, respectively. Species richness, effective diversity and abundance (measured as the number of individuals and insect biomass) of the beetle community were not significantly related to the rate of nitrogen application. However, nitrogen application changed the species distribution and weakly increased the evenness of species distribution, while this did not significantly change the species evenness. Species richness and abundance of herbivores and predators were not significantly related to the rate of nitrogen application. However, there were some variations in trophic responses to nitrogen. Species richness and abundance of detritivores increased with increasing nitrogen application.

  11. Quantification of motility of carabid beetles in farmland.

    Science.gov (United States)

    Allema, A B; van der Werf, W; Groot, J C J; Hemerik, L; Gort, G; Rossing, W A H; van Lenteren, J C

    2015-04-01

    Quantification of the movement of insects at field and landscape levels helps us to understand their ecology and ecological functions. We conducted a meta-analysis on movement of carabid beetles (Coleoptera: Carabidae), to identify key factors affecting movement and population redistribution. We characterize the rate of redistribution using motility μ (L2 T-1), which is a measure for diffusion of a population in space and time that is consistent with ecological diffusion theory and which can be used for upscaling short-term data to longer time frames. Formulas are provided to calculate motility from literature data on movement distances. A field experiment was conducted to measure the redistribution of mass-released carabid, Pterostichus melanarius in a crop field, and derive motility by fitting a Fokker-Planck diffusion model using inverse modelling. Bias in estimates of motility from literature data is elucidated using the data from the field experiment as a case study. The meta-analysis showed that motility is 5.6 times as high in farmland as in woody habitat. Species associated with forested habitats had greater motility than species associated with open field habitats, both in arable land and woody habitat. The meta-analysis did not identify consistent differences in motility at the species level, or between clusters of larger and smaller beetles. The results presented here provide a basis for calculating time-varying distribution patterns of carabids in farmland and woody habitat. The formulas for calculating motility can be used for other taxa. PMID:25673121

  12. Larval RNA interference in the red flour beetle, Tribolium castaneum.

    Science.gov (United States)

    Linz, David M; Clark-Hachtel, Courtney M; Borràs-Castells, Ferran; Tomoyasu, Yoshinori

    2014-01-01

    The red flour beetle, Tribolium castaneum, offers a repertoire of experimental tools for genetic and developmental studies, including a fully annotated genome sequence, transposon-based transgenesis, and effective RNA interference (RNAi). Among these advantages, RNAi-based gene knockdown techniques are at the core of Tribolium research. T. castaneum show a robust systemic RNAi response, making it possible to perform RNAi at any life stage by simply injecting double-stranded RNA (dsRNA) into the beetle's body cavity. In this report, we provide an overview of our larval RNAi technique in T. castaneum. The protocol includes (i) isolation of the proper stage of T. castaneum larvae for injection, (ii) preparation for the injection setting, and (iii) dsRNA injection. Larval RNAi is a simple, but powerful technique that provides us with quick access to loss-of-function phenotypes, including multiple gene knockdown phenotypes as well as a series of hypomorphic phenotypes. Since virtually all T. castaneum tissues are susceptible to extracellular dsRNA, the larval RNAi technique allows researchers to study a wide variety of tissues in diverse contexts, including the genetic basis of organismal responses to the outside environment. In addition, the simplicity of this technique stimulates more student involvement in research, making T. castaneum an ideal genetic system for use in a classroom setting. PMID:25350485

  13. Anatomical localization and stereoisomeric composition of Tribolium castaneum aggregation pheromones

    Science.gov (United States)

    Lu, Yujie; Beeman, Richard W.; Campbell, James F.; Park, Yoonseong; Aikins, Michael J.; Mori, Kenji; Akasaka, Kazuaki; Tamogami, Shigeyuki; Phillips, Thomas W.

    2011-09-01

    We report that the abdominal epidermis and associated tissues are the predominant sources of male-produced pheromones in the red flour beetle, Tribolium castaneum and, for the first time, describe the stereoisomeric composition of the natural blend of isomers of the aggregation pheromone 4,8-dimethyldecanal (DMD) in this important pest species. Quantitative analyses via gas chromatography-mass spectrometry showed that the average amount of DMD released daily by single feeding males of T. castaneum was 878 ± 72 ng (SE). Analysis of different body parts identified the abdominal epidermis as the major source of aggregation pheromone; the thorax was a minor source, while no DMD was detectable in the head. No internal organs or obvious male-specific glands were associated with pheromone deposition. Complete separation of all four stereoisomers of DMD was achieved following oxidation to the corresponding acid, derivatization with (1 R, 2 R)- and (1 S, 2 S)-2-(anthracene-2,3-dicarboximido)cyclohexanol to diastereomeric esters, and their separation on reversed-phase high-performance liquid chromatography at -54°C. Analysis of the hexane eluate from Porapak-Q-collected volatiles from feeding males revealed the presence of all four isomers (4 R,8 R)/(4 R,8 S)/(4 S,8 R)/(4 S,8 S) at a ratio of approximately 4:4:1:1. A walking orientation bioassay in a wind tunnel with various blends of the four synthetic isomers further indicated that the attractive potency of the reconstituted natural blend of 4:4:1:1 was equivalent to that of the natural pheromone and greater than that of the 1:1 blend of (4 R,8 R)/(4 R,8 S) used in commercial lures.

  14. Aggregated Computational Toxicology Resource (ACTOR)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Aggregated Computational Toxicology Resource (ACTOR) is a database on environmental chemicals that is searchable by chemical name and other identifiers, and by...

  15. Isolation and Aggregation in Economics

    OpenAIRE

    Schlicht, Ekkehart

    1985-01-01

    In explaining economic phenomena, economic analysis concentrates on selected influences and fixes the host of other factors under a ceteris paribus clause. This view, which goes back to Alfred Marshall (1842-1924), is developed in the first part of the book. Aggregation is viewed as a particular application of ceteris paribus analysis - isolation from "structural effects". This leads to an approach, called "closed aggregation", which was introduced by Kenneth May and is also implicit in Keyne...

  16. Judgment aggregation with consistency alone

    OpenAIRE

    Dietrich, Franz; List, Christian

    2007-01-01

    All existing impossibility theorems on judgment aggregation require individ- ual and collective judgment sets to be consistent and complete (in some recent results with completeness relaxed to deductive closure), arguably a demand- ing rationality requirement. They do not carry over to aggregation functions mapping pro…les of (merely) consistent individual judgment sets to (merely) consistent collective ones. We prove that, whenever the agenda of propositions under consideration exhibits mild...

  17. Judgment aggregation without full rationality

    OpenAIRE

    Dietrich, Franz; List, Christian

    2007-01-01

    Several recent results on the aggregation of judgments over logically connected propositions show that, under certain conditions, dictatorships are the only independent (i.e., propositionwise) aggregation rules generating fully rational (i.e., complete and consistent) collective judgments. A frequently mentioned route to avoid dictatorships is to allow incomplete collective judgments. We show that this route does not lead very far: we obtain (strong) oligarchies rather than dictatorships if i...

  18. Familial aggregation of cluster headache

    OpenAIRE

    Cruz, S; Lemos, C; Monteiro, JM

    2013-01-01

    Several studies suggest a strong familial aggregation for cluster headache (CH), but so far none of them have included subjects with probable cluster headache (PCH) in accordance with the International Classification of Headache Disorders. OBJECTIVE: To identify cases of probable cluster headache and to assess the familial aggregation of cluster headache by including these subjects. METHOD: Thirty-six patients attending a headache consultation and diagnosed with trigeminal autonom...

  19. Familial aggregation of cluster headache

    OpenAIRE

    Simao Cruz; Carolina Lemos; Jose Maria Pereira Monteiro

    2013-01-01

    Several studies suggest a strong familial aggregation for cluster headache (CH), but so far none of them have included subjects with probable cluster headache (PCH) in accordance with the International Classification of Headache Disorders. Objective To identify cases of probable cluster headache and to assess the familial aggregation of cluster headache by including these subjects. Method Thirty-six patients attending a headache consultation and diagnosed with trigeminal autonomic headache...

  20. Glycation precedes lens crystallin aggregation

    International Nuclear Information System (INIS)

    Non-enzymatic glycosylation (glycation) seems to have the potential to alter the structure of crystallins and make them susceptible to thiol oxidation leading to disulfide-linked high molecular weight (HMW) aggregate formation. They used streptozotocin diabetic rats during precataract and cataract stages and long-term cell-free glycation of bovine lens crystallins to study the relationship between glycation and lens crystallin aggregation. HMW aggregates and other protein components of the water-soluble (WS) and urea-soluble (US) fractions were separated by molecular sieve high performance liquid chromatography. Glycation was estimated by both [3H]NaBH4 reduction and phenylboronate agarose affinity chromatography. Levels of total glycated protein (GP) in the US fractions were about 2-fold higher than in the WS fractions and there was a linear increase in GP in both WS and US fractions. This increase was parallelled by a corresponding increase in HMW aggregates. Total GP extracted by the affinity method from the US fraction showed a predominance of HMW aggregates and vice versa. Cell-free glycation studies with bovine crystallins confirmed the results of the animals studies. Increasing glycation caused a corresponding increase in protein insolubilization and the insoluble fraction thus formed also contained more glycated protein. It appears that lens protein glycation, HMW aggregate formation, and protein insolubilization are interrelated

  1. Kinetic model for erythrocyte aggregation.

    Science.gov (United States)

    Bertoluzzo, S M; Bollini, A; Rasia, M; Raynal, A

    1999-01-01

    It is well known that light transmission through blood is the most widely utilized method for the study of erythrocyte aggregation. The curves obtained had been considered empirically as exponential functions. In consequence, the process becomes characterized by an only parameter that varies with all the process factors without discrimination. In the present paper a mathematical model for RBC aggregation process is deduced in accordance with von Smoluchowski's theory about the kinetics of colloidal particles agglomeration. The equation fitted the experimental pattern of the RBC suspension optical transmittance closely and contained two parameters that estimate the most important characteristics of the aggregation process separately, i.e., (1) average size of rouleaux at equilibrium and (2) aggregation rate. The evaluation of the method was assessed by some factors affecting erythrocyte aggregation, such as temperature, plasma dilutions, Dextran 500, Dextran 70 and PVP 360, at different media concentrations, cellular membrane alteration by the alkylating agent TCEA, and decrease of medium osmolarity. Results were interpreted considering the process characteristics estimated by the parameters, and there were also compared with similar studies carried out by other authors with other methods. This analysis allowed us to conclude that the equation proposed is reliable and useful to study erythrocyte aggregation. PMID:10660481

  2. Metagenomic profiling reveals lignocellulose degrading system in a microbial community associated with a wood-feeding beetle.

    Directory of Open Access Journals (Sweden)

    Erin D Scully

    Full Text Available The Asian longhorned beetle (Anoplophoraglabripennis is an invasive, wood-boring pest that thrives in the heartwood of deciduous tree species. A large impediment faced by A. glabripennis as it feeds on woody tissue is lignin, a highly recalcitrant biopolymer that reduces access to sugars and other nutrients locked in cellulose and hemicellulose. We previously demonstrated that lignin, cellulose, and hemicellulose are actively deconstructed in the beetle gut and that the gut harbors an assemblage of microbes hypothesized to make significant contributions to these processes. While lignin degrading mechanisms have been well characterized in pure cultures of white rot basidiomycetes, little is known about such processes in microbial communities associated with wood-feeding insects. The goals of this study were to develop a taxonomic and functional profile of a gut community derived from an invasive population of larval A. glabripennis collected from infested host trees and to identify genes that could be relevant for the digestion of woody tissue and nutrient acquisition. To accomplish this goal, we taxonomically and functionally characterized the A. glabripennis midgut microbiota through amplicon and shotgun metagenome sequencing and conducted a large-scale comparison with the metagenomes from a variety of other herbivore-associated communities. This analysis distinguished the A. glabripennis larval gut metagenome from the gut communities of other herbivores, including previously sequenced termite hindgut metagenomes. Genes encoding enzymes were identified in the A. glabripennis gut metagenome that could have key roles in woody tissue digestion including candidate lignin degrading genes (laccases, dye-decolorizing peroxidases, novel peroxidases and β-etherases, 36 families of glycoside hydrolases (such as cellulases and xylanases, and genes that could facilitate nutrient recovery, essential nutrient synthesis, and detoxification. This community

  3. Automated Data Aggregation for Time-Series Analysis: Study Case on Anaesthesia Data Warehouse.

    Science.gov (United States)

    Lamer, Antoine; Jeanne, Mathieu; Ficheur, Grégoire; Marcilly, Romaric

    2016-01-01

    Data stored in operational databases are not reusable directly. Aggregation modules are necessary to facilitate secondary use. They decrease volume of data while increasing the number of available information. In this paper, we present four automated engines of aggregation, integrated into an anaesthesia data warehouse. Four instances of clinical questions illustrate the use of those engines for various improvements of quality of care: duration of procedure, drug administration, assessment of hypotension and its related treatment. PMID:27071886

  4. QUERY PLANNING FOR CONTINUOUS AGGREGATION QUERIES USING DATA AGGREGATORS

    Directory of Open Access Journals (Sweden)

    A. SATEESH, D. ANIL, M. KIRANKUMAR

    2013-08-01

    Full Text Available Continuous aggregation queries are used to monitor the changes in data with time varying for online decision making. For continuous queries low cost and scalable techniques used a network of aggregators. Individual node cannot by itself determine its inclusion in the query result for this a different algorithmic challenges from aggregate and selection queries are presented. At specific coherencies each data item can serve for a set of data aggregators. Technique involves disseminating query into sub query and sub queries are executed on the chosen data aggregators. We build a query cost model which can be used to estimate the number of refresh messages which is required to satisfy the client specified incoherency bound. Performance results shows that by our method the query can be executed using less than one third the messages required for existing schemes. Our adaptive strategy employs distributed decisions made by the distributed servers independently based on localized statistics collected by each server at runtime. When comparatively static environment, propose two motionless tree construction algorithms relying on apriori system statistics. These static trees can also be used as early trees in a dynamic environment and apply our schemes to both single- and multi object distribution. Our extensive performance study illustrate that the adaptive mechanisms.

  5. Facilitating Dialogues about Racial Realities

    Science.gov (United States)

    Quaye, Stephen John

    2014-01-01

    Background/Context: Facilitating dialogues about racial issues in higher education classroom settings continues to be a vexing problem facing postsecondary educators. In order for students to discuss race with their peers, they need skilled facilitators who are knowledgeable about racial issues and able to support students in these difficult…

  6. Primary types of longhorned woodboring beetles (Coleoptera: Cerambycidae and Disteniidae) of the Smithsonian Institution

    Science.gov (United States)

    The primary types of longhorned woodboring beetles (Coleoptera: Cerambycidae, Disteniidae) of the National Museum of Natural History (Smithsonian Institution) are catalogued and figured, current through 2012 (but also including some 2013 holotypes). Data on the original combination, current combina...

  7. Mechanisms of Odor Coding in Coniferous Bark Beetles: From Neuron to Behavior and Application

    Directory of Open Access Journals (Sweden)

    Martin N. Andersson

    2012-01-01

    Full Text Available Coniferous bark beetles (Coleoptera: Curculionidae: Scolytinae locate their hosts by means of olfactory signals, such as pheromone, host, and nonhost compounds. Behavioral responses to these volatiles are well documented. However, apart from the olfactory receptor neurons (ORNs detecting pheromones, information on the peripheral olfactory physiology has for a long time been limited. Recently, however, comprehensive studies on the ORNs of the spruce bark beetle, Ips typographus, were conducted. Several new classes of ORNs were described and odor encoding mechanisms were investigated. In particular, links between behavioral responses and ORN responses were established, allowing for a more profound understanding of bark beetle olfaction. This paper reviews the physiology of bark beetle ORNs. Special focus is on I. typographus, for which the available physiological data can be put into a behavioral context. In addition, some recent field studies and possible applications, related to the physiological studies, are summarized and discussed.

  8. REVIEW: Research on insect biodiversity in Indonesia: Dung beetles (Coleoptera: Scarabaeidae and its role in ecosystem

    Directory of Open Access Journals (Sweden)

    SYAFRIDA MANUWOTO

    2005-04-01

    Full Text Available Research on insect biodiversity in Indonesia which is known as megabiodiversity still not yet a lot of done. Dung beetles represent one of insect group owning very important ecological role and enough suscebtible to condition change of an ecosistem so that is often made as one of bioindicator. Although it was estimated that there is about 1000 to 2000 species of dung beetle in Indo-Australia archipelago but the exact species number of Indonesia’s dung beetles not yet been known, since the are more than 17,000 islands in the country and different islands posseses a lot of endemic species. The lack of entomologist especially taxonomist and the limited of identification key available also become the problems of study on dung beetles biodiversity as well as another group of insect in Indonesia. Therefore, we need some effort expected to solve these problem in order to accelarate the research of insect biodiversity in Indonesia.

  9. Using lake sediment records to reconstruct bark beetle disturbances in western North America

    Directory of Open Access Journals (Sweden)

    Jesse Lee Morris

    2013-12-01

    Full Text Available The recent outbreak of native bark beetles in western North America is unprecedented in severity and scale, at least during the historical period. The aim of this work is to develop a proxy-based methodology to understand how bark beetle disturbances are recorded in lake sediments. Three hypotheses are tested to determine how the ecological impacts of severe spruce beetle (Dendroctonus rufipennis disturbances are recorded following mortality of Engelmann spruce (Picea engelmannii. Outbreaks are hypothesized to: (1 decrease the ratio of spruce to fir pollen; (2 increase soil erosion and mobilize terrestrial C; and (3 leach foliar N, enhancing algal productivity. To test these hypotheses, sediment cores from spruce beetle-affected basins were analyzed for pollen, insect remains, organic and minerogenic content, and isotopic and elemental concentrations. The dataset was tested statistically using generalized linear mixed models (GLMMs to determine if the response variables differed significantly between outbreak and non-outbreak periods. 

  10. Biological control of saltcedar (Tamarix spp.) by saltcedar leaf beetles (Diorhabda spp.): effects on small mammals

    Science.gov (United States)

    The spread of introduced saltcedar (Tamarix spp.) throughout many riparian systems across the western United States motivated the introduction of biological control agents that are specific to saltcedar, saltcedar leaf beetles (Diorhabda carinulata, D. elongata; Chrysomelidae). I monitored small mam...

  11. Critical Assessment of Risk Classification Systems for the Mountain Pine Beetle

    OpenAIRE

    Bentz, B J; Amman, G D; J. A. Logan

    1993-01-01

    Hazard/risk systems developed for mountain pine beetle management traditionally have attempted to describe the potential for timber loss in pine stands due to outbreak phase populations. A variety of stand and site characteristics, as well as climatic conditions, have been used. In this study, four hazard/risk systems were evaluated using data from 105 stands in northern Montana. None of the systems evaluated were found to predict adequately mountain pine beetle induced mortality which occurr...

  12. Plant-derived visual signals may protect beetle herbivores from bird predators

    OpenAIRE

    Tamar Keasar; Miriam Kishinevsky; Avi Shmida; Yoram Gerchman; Nicka Chinkov; Avi Koplovich; Gadi Katzir

    2013-01-01

    Insect herbivores often use chemical signals obtained from their food plants to deter enemies and/or attract sexual partners. Do plant-based visual signals act similarly, i.e., repel consumers' enemies and appeal to potential mates? We explored this question using the pollen-feeding beetle Pygopleurus israelitus (Glaphyridae), a specialized pollinator of Anemone coronaria's chemically defended red-morph flowers. We presented dead beetles, which had fed either on anemones or on cat-food, to yo...

  13. Bark beetles and fire: two forces of nature transforming western forests

    OpenAIRE

    Wells, Gail

    2012-01-01

    Bark beetles are chewing a wide swath through forests across North America. Over the past few years, infestations have become epidemic in lodgepole and spruce-fir forests of the Intermountain West. The resulting extensive acreages of dead trees are alarming the public and raising concern about risk of severe fire. Researchers supported by the Joint Fire Science Program (JFSP) are examining the complicated relationship between bark beetles and wildfire, the two most influential natural disturb...

  14. Contribution of Augosoma centaurus beetle to rural livelihoods in the East region of Cameroon : study report

    OpenAIRE

    F. J. Muafor; Le Gall, Philippe; Levang, Patrice

    2012-01-01

    This report describes the level to which forest dependent people in the East region of Cameroon rely on the consumption of Augosoma centaurus beetle (Dynastidae) for food security and rural livelihood. In total, 14 villages and 2 small towns, comprising of 9 ethnic groups in 10 sub-divisions were surveyed using quantitative and qualitative socioeconomic approaches. From the results of this study, both the larvae and adult individuals of the Augosoma beetle are traditional delic...

  15. The tiger beetles ( Coleoptera , Carabidae , Cicindelinae ) of Israel and adjacent lands

    OpenAIRE

    Matalin, Andrey V.; Chikatunov, Vladimir I.

    2016-01-01

    Abstract Based on field studies, museums collections and literature sources, the current knowledge of the tiger beetle fauna of Israel and adjacent lands is presented. In Israel eight species occur, one of them with two subspecies, while in the Sinai Peninsula nine species of tiger beetles are now known. In the combined regions seven genera from two tribes were found. The Rift Valley with six cicindelids species is the most specious region of Israel. Cylindera contorta valdenbergi and Cicinde...

  16. The tiger beetles (Coleoptera, Carabidae, Cicindelinae) of Israel and adjacent lands

    OpenAIRE

    Matalin,Andrey; I. Chikatunov,Vladimir

    2016-01-01

    Based on field studies, museums collections and literature sources, the current knowledge of the tiger beetle fauna of Israel and adjacent lands is presented. In Israel eight species occur, one of them with two subspecies, while in the Sinai Peninsula nine species of tiger beetles are now known. In the combined regions seven genera from two tribes were found. The Rift Valley with six cicindelids species is the most specious region of Israel. Cylindera contorta valdenbergi and Cicindela javeti...

  17. Contrasting needs of grassland dwellers: habitat preferences of endangered steppe beetles (Coleoptera)

    Czech Academy of Sciences Publication Activity Database

    Čížek, Lukáš; Hauck, David; Pokluda, Pavel

    2012-01-01

    Roč. 16, č. 2 (2012), s. 281-293. ISSN 1366-638X R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z50070508 Keywords : blister beetle * carpathian basin * darkling beetle Subject RIV: EH - Ecology, Behaviour Impact factor: 1.801, year: 2012 http://www.springerlink.com/content/h7523m513164v7l3/

  18. Analysis of the Wing Mechanism Movement Parameters of Selected Beetle Species (Coleoptera

    Directory of Open Access Journals (Sweden)

    Geisler T.

    2015-02-01

    Full Text Available This study presents a structural and functional analysis of the wing bending and folding mechanism of a selected beetle species. Insect motility studies, with regard to the anatomical structure, were performed. The main inner wing structures were highlighted and their mechanical properties and functions were determined. The structure parameters as mechanisms bodies that allow wings of various beetle species to bend and fold were defined.

  19. Aquatic beetles of the alpine lakes: diversity, ecology and small-scale population genetics

    OpenAIRE

    Čiamporová-Zaovičová Z.; Čiampor F.

    2011-01-01

    In this study, we summarize water beetle fauna of the alpine lakes and ponds of the Tatra Mountains. The literature and recent data were used to assess species diversity. Out of around 95 studied alpine water bodies, beetles were found in 61. Altogether, 54 taxa from six families were identified. The different altitudinal zones and lake areas were compared with species richness and species incidence concerning the sites sampled. Besides ...

  20. Dung beetles in an avian-dominated island ecosystem: feeding and trophic ecology.

    Science.gov (United States)

    Stavert, J R; Gaskett, A C; Scott, D J; Beggs, J R

    2014-09-01

    Globally, dung beetles (Scarabaeidae: Scarabaeinae) are linked to many critical ecosystem processes involving the consumption and breakdown of mammal dung. Endemic New Zealand dung beetles (Canthonini) are an anomaly, occurring at high abundance and low diversity on an island archipelago historically lacking terrestrial mammals, except bats, and instead dominated by birds. Have New Zealand's dung beetles evolved to specialise on bird dung or carrion, or have they become broad generalist feeders? We test dietary preferences by analysing nitrogen isotope ratios of wild dung beetles and by performing feeding behaviour observations of captive specimens. We also use nitrogen and carbon stable isotopes to determine if the dung beetle Saphobius edwardsi will consume marine-derived carrion. Nitrogen isotope ratios indicated trophic generalism in Saphobius dung beetles and this was supported by behavioural observations where a broad range of food resources were utilised. Alternative food resource use was further illustrated experimentally by nitrogen and carbon stable isotope signatures of S. edwardsi, where individuals provided with decomposed squid had δ(15)N and δ(13)C values that had shifted toward values associated with marine diet. Our findings suggest that, in the absence of native mammal dung resources, New Zealand dung beetles have evolved a generalist diet of dung and carrion. This may include marine-derived resources, as provided by the seabird colonies present in New Zealand forests before the arrival of humans. This has probably enabled New Zealand dung beetles to persist in indigenous ecosystems despite the decline of native birds and the introduction of many mammal species. PMID:24974270

  1. Agricultural Land Use Determines the Trait Composition of Ground Beetle Communities.

    Directory of Open Access Journals (Sweden)

    Helena I Hanson

    Full Text Available In order to improve biological control of agricultural pests, it is fundamental to understand which factors influence the composition of natural enemies in agricultural landscapes. In this study, we aimed to understand how agricultural land use affects a number of different traits in ground beetle communities to better predict potential consequences of land-use change for ecosystem functioning. We studied ground beetles in fields with different agricultural land use ranging from frequently managed sugar beet fields, winter wheat fields to less intensively managed grasslands. The ground beetles were collected in emergence tents that catch individuals overwintering locally in different life stages and with pitfall traps that catch individuals that could have a local origin or may have dispersed into the field. Community weighted mean values for ground beetle traits such as body size, flight ability and feeding preference were estimated for each land-use type and sampling method. In fields with high land-use intensity the average body length of emerging ground beetle communities was lower than in the grasslands while the average body length of actively moving communities did not differ between the land-use types. The proportion of ground beetles with good flight ability or a carnivorous diet was higher in the crop fields as compared to the grasslands. Our study highlights that increasing management intensity reduces the average body size of emerging ground beetles and the proportion of mixed feeders. Our results also suggest that the dispersal ability of ground beetles enables them to compensate for local management intensities.

  2. Agricultural Land Use Determines the Trait Composition of Ground Beetle Communities.

    Science.gov (United States)

    Hanson, Helena I; Palmu, Erkki; Birkhofer, Klaus; Smith, Henrik G; Hedlund, Katarina

    2016-01-01

    In order to improve biological control of agricultural pests, it is fundamental to understand which factors influence the composition of natural enemies in agricultural landscapes. In this study, we aimed to understand how agricultural land use affects a number of different traits in ground beetle communities to better predict potential consequences of land-use change for ecosystem functioning. We studied ground beetles in fields with different agricultural land use ranging from frequently managed sugar beet fields, winter wheat fields to less intensively managed grasslands. The ground beetles were collected in emergence tents that catch individuals overwintering locally in different life stages and with pitfall traps that catch individuals that could have a local origin or may have dispersed into the field. Community weighted mean values for ground beetle traits such as body size, flight ability and feeding preference were estimated for each land-use type and sampling method. In fields with high land-use intensity the average body length of emerging ground beetle communities was lower than in the grasslands while the average body length of actively moving communities did not differ between the land-use types. The proportion of ground beetles with good flight ability or a carnivorous diet was higher in the crop fields as compared to the grasslands. Our study highlights that increasing management intensity reduces the average body size of emerging ground beetles and the proportion of mixed feeders. Our results also suggest that the dispersal ability of ground beetles enables them to compensate for local management intensities. PMID:26730734

  3. Diagnostic methods of pollen beetle and other winter rape pests resistance to insecticides

    OpenAIRE

    Herman, Jan

    2013-01-01

    The literature review summarizes informations about pests of winter oilseed rape, problem of pest resistance to insecticides, mechanisms of resistance of insects to insecticides and methods, how to evaluate the resistance, and the emergence and development of resistance of pollen beetle to pyrethroids in Europe and in the Czech Republic. In the experimental part of the master‘s thesis, resistance of pollen beetle from 5 locations in the Czech Republic to the three selected pyrethroids (deltam...

  4. Impact of anthropogenic disturbances on beetle communities of French Mediterranean coastal dunes

    OpenAIRE

    Comor, V.N.R.; Orgeas, J.; Ponel, P; Rolando, C.; Delettre, Y.R.

    2008-01-01

    In coastal dunes, influenced by anthropogenic activities such as tourism, it is important to determine the relative influence of environmental factors at different spatial scales to evaluate the sensitivity of local communities to disturbances. We analyzed beetle communities of 14 dunes of the French Mediterranean coast: four in the relatively preserved Camargue area, and ten in the Var department, where tourism is intensive. Beetle communities were studied three times in early spring using s...

  5. Parental effects and flight behaviour in the burying beetle, Nicrophorus vespilloides

    OpenAIRE

    Attisano, Alfredo; Kilner, Rebecca M.

    2015-01-01

    Parents play a key role in determining the phenotype of their offspring. However, relatively few studies have investigated whether parents can change their offspring's behaviour in a sustained way that persists into adulthood. With experiments on the burying beetle, Nicrophorus vespilloides, we investigated how the developmental environment created by parents affects their offspring's wing morphology in adulthood, and the correlated effects on adult flight behaviour. Burying beetles exhibit c...

  6. Laboratory evaluation of some indigenous plant extracts as toxicants against red flour beetle, Tribolium castaneum Herbst

    OpenAIRE

    Mamum, M.S.A; Shahjahan, M.; Ahmad, M.

    2009-01-01

    Experiments were carried out to evaluate the toxicity of six botanicals, Bazna (Zanthoxylum rhetsa), Ghora-neem (Melia sempervirens), Hijal (Barringtonia acutangula), Karanja (Pongamia pinnata), Mahogoni (Swietenia mahagoni) and Neem (Azadirachta indica) against red flour beetle, Tribolium castaneum Herbst. Leaf and seed extracts were prepared by using acetone, methanol and water as solvents. The results showed that extracts of all the six plants had direct toxic effect on red flour beetle. A...

  7. Beetle-Grow: An Effective Intelligent Tutoring System to Support Conceptual Change

    OpenAIRE

    Farrow, Elaine; Moore, Johanna D.

    2016-01-01

    We will demonstrate the Beetle-Grow intelligent tutoring system, which combines active experimentation, self-explanation, and formative feedback using natural language interaction. It runs in a standard web browser and has a fresh, engaging design. The underlying back-end system has previously been shown to be highly effective in teaching basic electricity and electronics concepts.Beetle-Grow has been designed to capture student interaction and indicators of learning in a form suitable for da...

  8. Saproxylic Beetle Assemblage Selection as Determining Factor of Species Distributional Patterns: Implications for Conservation

    OpenAIRE

    García López, Alejandra; Galante, Eduardo; Micó, Estefanía

    2016-01-01

    The knowledge of the distributional patterns of saproxylic beetles is essential for conservation biology due to the relevance of this fauna in the maintenance of ecological processes and the endangerment of species. The complex community of saproxylic beetles is shaped by different assemblages that are composed of species linked by the microhabitats they use. We evaluate how different the species distribution patterns that are obtained can be, depending on the analyzed assemblage and to what ...

  9. Evaluating leaf litter beetle data sampled by Winkler extraction from Atlantic forest sites in southern Brazil

    OpenAIRE

    Philipp Werner Hopp; Edilson Caron; Richard Ottermanns; Martina Roß-Nickoll

    2011-01-01

    Evaluating leaf litter beetle data sampled by Winkler extraction from Atlantic forest sites in southern Brazil. To evaluate the reliability of data obtained by Winkler extraction in Atlantic forest sites in southern Brazil, we studied litter beetle assemblages in secondary forests (5 to 55 years after abandonment) and old-growth forests at two seasonally different points in time. For all regeneration stages, species density and abundance were lower in April compared to August; but, assemblage...

  10. Mountain pine beetles and emerging issues in the management of woodland caribou in Westcentral British Columbia

    Directory of Open Access Journals (Sweden)

    Deborah Cichowski

    2005-05-01

    Full Text Available The Tweedsmuir—Entiako caribou (Rangifer tarandus caribou herd summers in mountainous terrain in the North Tweedsmuir Park area and winters mainly in low elevation forests in the Entiako area of Westcentral British Columbia. During winter, caribou select mature lodgepole pine (Pinus contorta forests on poor sites and forage primarily by cratering through snow to obtain terrestrial lichens. These forests are subject to frequent large-scale natural disturbance by fire and forest insects. Fire suppression has been effective in reducing large-scale fires in the Entiako area for the last 40—50 years, resulting in a landscape consisting primarily of older lodgepole pine forests, which are susceptible to mountain pine beetle (Dendroctonus ponderosae attack. In 1994, mountain pine beetles were detected in northern Tweedsmuir Park and adjacent managed forests. To date, mountain pine beetles have attacked several hundred thousand hectares of caribou summer and winter range in the vicinity of Tweedsmuir Park, and Entiako Park and Protected Area. Because an attack of this scale is unprecedented on woodland caribou ranges, there is no information available on the effects of mountain pine beetles on caribou movements, habitat use or terrestrial forage lichen abundance. Implications of the mountain pine beetle epidemic to the Tweedsmuir—Entiako woodland caribou population include effects on terrestrial lichen abundance, effects on caribou movement (reduced snow interception, blowdown, and increased forest harvesting outside protected areas for mountain pine beetle salvage. In 2001 we initiated a study to investigate the effects of mountain pine beetles and forest harvesting on terrestrial caribou forage lichens. Preliminary results suggest that the abundance of Cladina spp. has decreased with a corresponding increase in kinnikinnick (Arctostaphylos uva-ursi and other herbaceous plants. Additional studies are required to determine caribou movement and

  11. Comparative analysis of microbial diversity in Longitarsus flea beetles (Coleoptera: Chrysomelidae).

    Science.gov (United States)

    Kelley, Scott T; Dobler, Susanne

    2011-05-01

    Herbivorous beetles comprise a significant fraction of eukaryotic biodiversity and their plant-feeding adaptations make them notorious agricultural pests. Despite more than a century of research on their ecology and evolution, we know little about the diversity and function of their symbiotic microbial communities. Recent culture-independent molecular studies have shown that insects possess diverse gut microbial communities that appear critical for their survival. In this study, we combined culture-independent methods and high-throughput sequencing strategies to perform a comparative analysis of Longitarsus flea-beetles microbial community diversity (MCD). This genus of beetle herbivores contains host plant specialists and generalists that feed on a diverse array of toxic plants. Using a deep-sequencing approach, we characterized the MCD of eleven Longitarsus species across the genus, several of which represented independent shifts to the same host plant families. Database comparisons found that Longitarsus-associated microbes came from two habitat types: insect guts and the soil rhizosphere. Statistical clustering of the Longitarsus microbial communities found little correlation with the beetle phylogeny, and uncovered discrepancies between bacterial communities extracted directly from beetles and those from frass. A Principal Coordinates Analysis also found some correspondence between beetle MCD and host plant family. Collectively, our data suggest that environmental factors play a dominant role in shaping Longitarsus MCD and that the root-feeding beetle larvae of these insects are inoculated by soil rhizosphere microbes. Future studies will investigate MCD of select Longitarsus species across their geographic ranges and explore the connection between the soil rhizosphere and the beetle MCD. PMID:20844936

  12. Microsatellite loci for the small hive beetle, Aethina tumida, a nest parasite of honey bees.

    Science.gov (United States)

    Evans, J D; Spiewok, S; Teixeira, E W; Neumann, P

    2008-05-01

    Aethina tumida, a beetle parasite of honey bee colonies, has recently and dramatically expanded its range and now parasitizes honey bees on three continents. Polymorphic microsatellite loci for this beetle species will help map this continuing range expansion, and will also prove useful for exploring the mating system and local gene flow patterns for this important parasite. We describe 15 loci that are polymorphic in both the native and introduced ranges of this species, showing from two to 22 alleles. PMID:21585875

  13. The influence of light on small hive beetle (Aethina tumida) behavior and trap capture

    OpenAIRE

    Duehl, Adrian; Arbogast, Richard; Sheridan, Audrey; Teal, Peter

    2012-01-01

    International audience The small hive beetle (Aethina tumida, Murray) is a major pest of honeybee (Apis mellifera) colonies, particularly in the Southeastern USA. We evaluated the small hive beetle's (SHB) response to different wavelengths of the light spectrum and found that SHB larvae and adults were most attracted to the 390 nm wavelength. Early instar larvae were not significantly attracted to light, while wandering larvae and adults exhibited strong positive phototaxis. The light resp...

  14. Assessment of post-beetle impacts on natural regeneration of Lodgepole Pine

    OpenAIRE

    Egger, Keith N; Arocena, Joselito; Green, Scott; Kennedy, Nabla; Massicotte, Hugues; Scholefield, Scott

    2009-01-01

    The ecological disturbance from wildfire (2004) on ~ 10,000 hectares of forests near the Kenny Dam presented a unique opportunity to study the natural and artificial regeneration in burned mountain pine beetle (Dendroctonus ponderosae Hopkins) infested stands in north-central British Columbia. Mountain pine beetle (MPB) has been documented as a natural disturbance agent that may precede wildfire in lodgepole pine forests (Pinus contorta var. latifolia). The objectives of this study were to i)...

  15. Mechanistic origins of bombardier beetle (Brachinini) explosion-induced defensive spray pulsation

    OpenAIRE

    Arndt, Eric Michael; Moore, Wendy; Lee, Wah-Keat; Ortiz, Christine

    2014-01-01

    Bombardier beetles (Brachinini) use a rapid series of discrete explosions inside their pygidial gland reaction chambers to produce a hot, pulsed, quinone-based defensive spray. The mechanism of brachinines’ spray pulsation was explored using anatomical studies and direct observation of explosions inside living beetles using synchrotron x-ray imaging. Quantification of the dynamics of vapor inside the reaction chamber indicates that spray pulsation is controlled by specialized, contiguous cuti...

  16. Incorporating a Sorghum Habitat for Enhancing Lady Beetles (Coleoptera: Coccinellidae) in Cotton

    OpenAIRE

    P. G. Tillman; Cottrell, T. E.

    2012-01-01

    Lady beetles (Coleoptera: Coccinellidae) prey on insect pests in cotton. The objective of this 2 yr on-farm study was to document the impact of a grain sorghum trap crop on the density of Coccinellidae on nearby cotton. Scymnus spp., Coccinella septempunctata (L.), Hippodamia convergens Guérin-Méneville, Harmonia axyridis (Pallas), Coleomegilla maculata (De Geer), Cycloneda munda (Say), and Olla v-nigrum (Mulsant) were found in sorghum over both years. Lady beetle compositions in sorghum and ...

  17. Analysis of the Wing Mechanism Movement Parameters of Selected Beetle Species (Coleoptera)

    OpenAIRE

    Geisler T.; Topczewska S.

    2015-01-01

    This study presents a structural and functional analysis of the wing bending and folding mechanism of a selected beetle species. Insect motility studies, with regard to the anatomical structure, were performed. The main inner wing structures were highlighted and their mechanical properties and functions were determined. The structure parameters as mechanisms bodies that allow wings of various beetle species to bend and fold were defined.

  18. Fractal Aggregates in Tennis Ball Systems

    Science.gov (United States)

    Sabin, J.; Bandin, M.; Prieto, G.; Sarmiento, F.

    2009-01-01

    We present a new practical exercise to explain the mechanisms of aggregation of some colloids which are otherwise not easy to understand. We have used tennis balls to simulate, in a visual way, the aggregation of colloids under reaction-limited colloid aggregation (RLCA) and diffusion-limited colloid aggregation (DLCA) regimes. We have used the…

  19. An exact approach for aggregated formulations

    DEFF Research Database (Denmark)

    Gamst, Mette; Spoorendonk, Simon; Røpke, Stefan

    Aggregating formulations is a powerful approach for problems to take on tractable forms. Aggregation may lead to loss of information, i.e. the aggregated formulation may be an approximation of the original problem. In branch-and-bound context, aggregation can also complicate branching, e.g. when...... optimality cannot be guaranteed by branching on aggregated variables. We present a generic exact solution method to remedy the drawbacks of aggregation. It combines the original and aggregated formulations and applies Benders' decomposition. We apply the method to the Split Delivery Vehicle Routing Problem....

  20. Treating cattle with antibiotics affects greenhouse gas emissions, and microbiota in dung and dung beetles.

    Science.gov (United States)

    Hammer, Tobin J; Fierer, Noah; Hardwick, Bess; Simojoki, Asko; Slade, Eleanor; Taponen, Juhani; Viljanen, Heidi; Roslin, Tomas

    2016-05-25

    Antibiotics are routinely used to improve livestock health and growth. However, this practice may have unintended environmental impacts mediated by interactions among the wide range of micro- and macroorganisms found in agroecosystems. For example, antibiotics may alter microbial emissions of greenhouse gases by affecting livestock gut microbiota. Furthermore, antibiotics may affect the microbiota of non-target animals that rely on dung, such as dung beetles, and the ecosystem services they provide. To examine these interactions, we treated cattle with a commonly used broad-spectrum antibiotic and assessed downstream effects on microbiota in dung and dung beetles, greenhouse gas fluxes from dung, and beetle size, survival and reproduction. We found that antibiotic treatment restructured microbiota in dung beetles, which harboured a microbial community distinct from those in the dung they were consuming. The antibiotic effect on beetle microbiota was not associated with smaller size or lower numbers. Unexpectedly, antibiotic treatment raised methane fluxes from dung, possibly by altering the interactions between methanogenic archaea and bacteria in rumen and dung environments. Our findings that antibiotics restructure dung beetle microbiota and modify greenhouse gas emissions from dung indicate that antibiotic treatment may have unintended, cascading ecological effects that extend beyond the target animal. PMID:27226475

  1. Intraspecific and interspecific attraction of three Tomicus beetle species during the shoot-feeding phase.

    Science.gov (United States)

    Wang, J; Zhang, Z; Kong, X; Wang, H; Zhang, S

    2015-04-01

    The shoot beetles Tomicus minor, Tomicus yunnanensis, and Tomicus brevipilosus have been decimating Pinus yunnanensis trees for more than 30 years in Southwestern China. To understand the chemical ecological relationship between pines and Tomicus, and among the three beetle species, we compared the attraction of these beetles to damaged shoots, extracts from damaged shoots, and volatiles from damaged shoots collected by the dynamic headspace sampling method. Experiments were performed using a modified open-arena olfactometer. The male T. minor and both sexes of T. brevipilosus were more strongly attracted to damaged shoots than to undamaged shoots and they showed attraction to shoots damaged by the same species. Female T. minor and both sexes of T. yunnanensis were attracted to shoots damaged by female T. brevipilosus. The three beetle species were attracted to shoot extracts and dynamic headspace volatiles from shoots damaged by the same species and sex. Female T. minor and male T. yunnanensis were also attracted to dynamic headspace volatiles from shoots damaged by both sexes of T. brevipilosus. The results suggested that specific semiochemicals that are induced or produced by T. brevipilosus also attract T. minor and T. yunnanensis. The semiochemicals in damaged shoots affect the attraction of the three beetle species and play an important chemical communication role in weakening the host trees during the beetles' shoot-feeding phase. PMID:25632972

  2. The role of dung beetles in reducing greenhouse gas emissions from cattle farming

    Science.gov (United States)

    Slade, Eleanor M.; Riutta, Terhi; Roslin, Tomas; Tuomisto, Hanna L.

    2016-01-01

    Agriculture is one of the largest anthropogenic sources of greenhouse gases (GHGs), with dairy and beef production accounting for nearly two-thirds of emissions. Several recent papers suggest that dung beetles may affect fluxes of GHGs from cattle farming. Here, we put these previous findings into context. Using Finland as an example, we assessed GHG emissions at three scales: the dung pat, pasture ecosystem, and whole lifecycle of milk or beef production. At the first two levels, dung beetles reduced GHG emissions by up to 7% and 12% respectively, mainly through large reductions in methane (CH4) emissions. However, at the lifecycle level, dung beetles accounted for only a 0.05-0.13% reduction of overall GHG emissions. This mismatch derives from the fact that in intensive production systems, only a limited fraction of all cow pats end up on pastures, offering limited scope for dung beetle mitigation of GHG fluxes. In contrast, we suggest that the effects of dung beetles may be accentuated in tropical countries, where more manure is left on pastures, and dung beetles remove and aerate dung faster, and that this is thus a key area for future research. These considerations give a new perspective on previous results perspective, and suggest that studies of biotic effects on GHG emissions from dung pats on a global scale are a priority for current research.

  3. Observations on the Cave-Associated Beetles (Coleoptera of Nova Scotia, Canada

    Directory of Open Access Journals (Sweden)

    Moseley M.

    2009-07-01

    Full Text Available The cave-associated invertebrates of Nova Scotia constitute a fauna at a very early stage of post-glacial recolonization. TheColeoptera are characterized by low species diversity. A staphylinid Quedius spelaeus spelaeus, a predator, is the only regularlyencountered beetle. Ten other terrestrial species registered from cave environments in the province are collected infrequently. Theyinclude three other rove-beetles: Brathinus nitidus, Gennadota canadensis and Atheta annexa. The latter two together with Catopsgratiosus (Leiodidae constitute a small group of cave-associated beetles found in decompositional situations. Quedius s. spelaeusand a small suite of other guanophiles live in accumulations of porcupine dung: Agolinus leopardus (Scarabaeidae, Corticariaserrata (Latrididae, and Acrotrichis castanea (Ptilidae. Two adventive weevils Otiorhynchus ligneus and Barypeithes pellucidus(Curculionidae collected in shallow cave passages are seasonal transients; Dermestes lardarius (Dermestidae, recorded fromone cave, was probably an accidental (stray. Five of the terrestrial beetles are adventive Palaearctic species. Aquatic beetles arecollected infrequently. Four taxa have been recorded: Agabus larsoni (Dytiscidae may be habitual in regional caves; another Agabussp. (probably semivittatus, Dytiscus sp. (Dytiscidae, and Crenitis digesta (Hydrophilidae are accidentals. The distribution andecology of recorded species are discussed, and attention is drawn to the association of beetles found in a Nova Scotia “ice cave”.

  4. Dung beetles use their dung ball as a mobile thermal refuge.

    Science.gov (United States)

    Smolka, Jochen; Baird, Emily; Byrne, Marcus J; el Jundi, Basil; Warrant, Eric J; Dacke, Marie

    2012-10-23

    At midday, surface temperatures in the desert often exceed 60°C. To be active at this time, animals need extraordinary behavioural or physiological adaptations. Desert ants, for instance, spend up to 75% of their foraging time cooling down on elevated thermal refuges such as grass stalks. Ball-rolling dung beetles work under similar thermal conditions in South African savannahs. After landing at a fresh dung pile, a beetle quickly forms a dung ball and rolls it away in a straight line, head down, walking backwards. Earlier studies have shown that some dung beetles maintain an elevated body temperature to gain a competitive advantage, and that heat shunting may prevent overheating during flight. However, we know little about the behavioural strategies beetles might employ to mitigate heat stress while rolling their dung balls. Using infrared thermography and behavioural experiments, we show here that dung beetles use their dung ball as a mobile thermal refuge onto which they climb to cool down while rolling across hot soil. We further demonstrate that the moist ball functions not only as a portable platform, but also as a heat sink, which effectively cools the beetle as it rolls or climbs onto it. PMID:23098590

  5. Generation and Exploitation of Aggregation Abstractions for Scheduling and Resource Allocation

    Science.gov (United States)

    Linden, Theodore A.; Lowry, Michael R.

    1992-01-01

    Our research is investigating abstraction of computational theories for scheduling and resource allocation. These theories are represented in a variant of first order predicate calculus, parameterized multisorted logic, that facilitates specification of large problems. A particular problem is conceptually stated as a set of ground sentences that are consistent with a quantified theory. We are mainly investigating the automated generation of aggregation abstractions and approximations in which detailed resource allocation constraints are replaced by constraints between aggregate demand and capacity. We are also investigating the interaction of aggregation abstractions with the more thoroughly investigated abstractions of weakening operator preconditions. The purpose of the theories for aggregated demand/capacity is threefold: first, to answer queries about aggregate properties, such as gross feasibility; second, to reduce computational costs by using the solution of aggregate problems to guide the solution of detailed problems; and third, to facilitate reformulating theories to approximate problems for which there are efficient problem solving methods. We also describe novel methods for exploiting aggregation abstractions.

  6. Long-term dynamics of leafy spurge (Euphorbia esula) and its biocontrol agent, flea beetles in the genus Aphthona

    Science.gov (United States)

    Larson, Diane L.; Grace, James B.; Larson, Jennifer L.

    2008-01-01

    Three flea beetle species (Aphthona spp.), first introduced into North America in 1988, have come to be regarded as effective biological control organisms for leafy spurge (Euphorbia esula). The black flea beetles (Aphthona lacertosa and A. czwalinae) in particular have been shown to cause reductions in leafy spurge stem counts in the northern Great Plains, while the brown flea beetle (A. nigriscutis) has persisted and spread, but has not been found to be as effective at controlling leafy spurge. The ability of black flea beetles to control leafy spurge in any given year, however, has been found to vary. To better understand the long-term effects of flea beetle herbivory on leafy spurge, we monitored stem counts of leafy spurge and numbers of black and brown flea beetles at three sites on two National Wildlife Refuges in east-central North Dakota, USA, from 1998 to 2006. Brown flea beetle numbers were observed to be negligible on these sites. Over the 9 years of the study, black flea beetles were seen to spread over the three study sites and leafy spurge stem counts declined substantially on two of the three sites. Even at low densities of spurge, black flea beetle populations persisted, a necessary prerequisite for long-term control. We used structural equation models (SEM) to assess the yearly effects of black flea beetles, soil texture, and refuge site on leafy spurge stem counts over this time period. We then used equations developed from the SEM analysis to explore flea beetle–leafy spurge dynamics over time, after controlling for soil texture and refuge. Yearly effect strength of black flea beetles on leafy spurge was found to be modest, largely owing to substantial spatial variability in control. However, simulation results based on prediction coefficients revealed leafy spurge to be highly responsive to increases in flea beetle populations on average.

  7. The biology of the small hive beetle (Aethina tumida, Coleoptera: Nitidulidae): Gaps in our knowledge of an invasive species

    OpenAIRE

    Neumann, Peter; Elzen, Patti

    2004-01-01

    International audience Small hive beetles, Aethina tumida, are honeybee parasites native to Africa, where they are a minor pest only. In contrast, the beetles can be harmful parasites of European honeybee subspecies. Resistance of African subspecies to infestations is probably due to quantitative differences in a series of behaviours such as absconding, aggression, removal of parasite eggs and larvae and social encapsulation. The beetles use counter-resistance tactics such as defence postu...

  8. Mimicking unfolding motion of a beetle hind wing

    Institute of Scientific and Technical Information of China (English)

    MUHAMMAD Azhar; PARK Hoon C; HWANG Do Y; BYUN Doyoung; GOO Nam S

    2009-01-01

    This paper presents an experimental research aiming to realize an artificial hind wing that can mimic the wing unfolding motion of Allomyrina dichotoma, an insect in coleopteran order. Based on the understanding of working principles of beetle wing folding/unfolding mechanisms, the hind wing unfolding motion is mimicked by a combination of creative ideas and state-of-art artificial muscle actuator. In this work, we devise two types of artificial wings and the successfully demonstrate that they can be unfolded by actuation of shape memory alloy wires to provide actuation force at the wing base and along the leading edge vein. The folding/unfolding mechanisms may provide an insight for portable nano/micro air vehicles with morphing wings.

  9. The complete mitochondrial genome of the flea beetle Agasicles hygrophila.

    Science.gov (United States)

    Li, Na; Wei, Jia-Ning; Jia, Dong; Li, Shuang; Ma, Rui-Yan

    2016-09-01

    To provide molecular markers for population genetic analysis of the flea beetle Agasicles hygrophila, we determined its mitochondrial genome (mitogenome) for the first time. The mitogenome of A. hygrophila was 15 917 bp in length with an AT content of 75.15%. It had the typical set of 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and an AT-rich control region. Compared with the ancestral mitogenome of insects, no gene rearrangement occurred in A. hygrophila. Incomplete stop codons were present in PCGs of A. hygrophila. All tRNA genes except for trnS(AGN) could form the typical clover-leaf secondary structures. The phylogenetic analysis indicated that A. hygrophila was close to other species belonging to the same family of Chrysomelidae. PMID:26368047

  10. Effects of polyhydroxy compounds on beetle antifreeze protein activity

    Science.gov (United States)

    Amornwittawat, Natapol; Wang, Sen; Banatlao, Joseph; Chung, Melody; Velasco, Efrain; Duman, John G.; Wen, Xin

    2016-01-01

    Antifreeze proteins (AFPs) noncolligatively depress the nonequilibrium freezing point of a solution and produce a difference between the melting and freezing points termed thermal hysteresis (TH). Some low-molecular-mass solutes can affect the TH values. The TH enhancement effects of selected polyhydroxy compounds including polyols and carbohydrates on an AFP from the beetle Dendroides canadensis were systematically investigated using differential scanning calorimetry (DSC). The number of hydroxyl groups dominates the molar enhancement effectiveness of polyhydroxy compounds having one to five hydroxyl groups. However, the above rule does not apply for polyhydroxy compounds having more than five hydroxyl groups. The most efficient polyhydroxy enhancer identified is trehalose. In a combination of enhancers the strongest enhancer plays the major role in determining the TH enhancement. Mechanistic insights into identification of highly efficient AFP enhancers are discussed. PMID:19038370

  11. Mountain pine beetle impacts on vegetation and carbon stocks

    Science.gov (United States)

    Hawbaker, Todd J.; Briggs, Jennifer S.; Caldwell, Megan K.; Stitt, Susan

    2013-01-01

    In the Southern Rocky Mountains, an epidemic outbreak of mountain pine beetle (Dendroctonus ponderosae; MPB) has caused levels of tree mortality unprecedented in recorded history. The impacts of this mortality on vegetation composition, forest structure, and carbon stocks have only recently received attention, although the impacts of other disturbances such as fires and land-use/land-cover change are much better known. This study, initiated in 2010, aims to increase our understanding of MPB outbreaks and their impacts. We have integrated field-collected data with vegetation simulation models to assess and quantify how long-term patterns of vegetation and carbon stocks have and may change in response to MPB outbreaks and other disturbances.

  12. Elastocapilllarity in insect adhesion: the case of beetle adhesive hair

    Science.gov (United States)

    Gernay, Sophie; Gilet, Tristan; Lambert, Pierre; Federle, Walter

    2014-11-01

    The feet of many insects are covered with dense arrays of hair-like structures called setae. Liquid capillary bridges at the tip of these micrometric structures are responsible for the controlled adhesion of the insect on a large variety of substrates. The resulting adhesion force can exceed several times the body weight of the insect. The high aspect-ratio of setae suggests that flexibility is a key ingredient in this capillary-based adhesion mechanism. There is indeed a strong coupling between their elastic deformation and the shape of the liquid meniscus. In this experimental work, we observe and quantify the local deflection of dock beetle seta tips under perpendicular loading using interference microscopy. Our results are then interpreted in the light of an analytic model of elastocapillarity. This research has been funded by the FRIA/FNRS and the Interuniversity Attraction Poles Programme (IAP 7/38 MicroMAST) initiated by the Belgian Science Policy Office.

  13. Confirmation of bean leaf beetle, Cerotoma trifurcata, feeding on cucurbits

    Directory of Open Access Journals (Sweden)

    R.L. Koch

    2004-02-01

    Full Text Available The objective of these studies was to assess the degree to which bean leaf beetle, Cerotoma trifurcata (Forster, will feed on cucurbits. In 2003, we documented an infestation of C. trifurcata in a commercial pumpkin field near Rosemount, MN, USA. To evaluate C. trifurcata feeding on cucurbits, we conducted laboratory no-choice and choice test feeding studies. In the laboratory, C. trifurcata fed most heavily on cotyledon-stage cucumber plants, followed by pumpkin and squash. With soybean plants present, C. trifurcata still fed on cucumber plants. However, C. trifurcata appeared to prefer soybeans until the quality of the soybean plants was diminished through feeding damage. This is the first known report of C. trifurcata feeding on cucurbits. The pest potential of C. trifurcata in cucurbit cropping systems should be further evaluated.

  14. Deforestation and apparent extinctions of endemic forest beetles in Madagascar.

    Science.gov (United States)

    Hanski, Ilkka; Koivulehto, Helena; Cameron, Alison; Rahagalala, Pierre

    2007-06-22

    Madagascar has lost about half of its forest cover since 1953 with much regional variation, for instance most of the coastal lowland forests have been cleared. We sampled the endemic forest-dwelling Helictopleurini dung beetles across Madagascar during 2002-2006. Our samples include 29 of the 51 previously known species for which locality information is available. The most significant factor explaining apparent extinctions (species not collected by us) is forest loss within the historical range of the focal species, suggesting that deforestation has already caused the extinction, or effective extinction, of a large number of insect species with small geographical ranges, typical for many endemic taxa in Madagascar. Currently, roughly 10% of the original forest cover remains. Species-area considerations suggest that this will allow roughly half of the species to persist. Our results are consistent with this prediction. PMID:17341451

  15. Destructive Strength Properties of Recycled Coarse Aggregate

    OpenAIRE

    Chetna M Vyas,; Darshana R Bhatt,

    2013-01-01

    Due to a critical shortage of natural aggregate, the availability of demolished concrete for use as recycled coarse aggregate (RCA) is increasing. Use of waste concrete as RCA conserves natural aggregate, reduces the impact on landfills, save energy and can provide cost benefit. Recycled aggregates are the materials for the future. The application of recycled aggregate has been started in many Asian & Western countries for construction projects. Research Paper reports the basic strength prope...

  16. Erythrocyte aggregation: Basic aspects and clinical importance

    OpenAIRE

    Başkurt, Oğuz K.; Meiselman, Herbert J.

    2013-01-01

    Red blood cells (RBC) aggregate to form two- and three-dimensional structures when suspended in aqueous solutions containing large plasma proteins or polymers; this aggregation is reversible and shear dependent (i.e., dispersed at high shear and reformed at low or stasis). The extent of aggregation is the main determinant of low shear blood viscosity, thus predicting an inverse relationship between aggregation and in vivo blood flow. However, the effects of aggregation on hemodynamic mechanis...

  17. Individual income, incomplete information, and aggregate consumption

    OpenAIRE

    Pischke, J.

    1991-01-01

    In this paper I study a model of life-cycle consumption in which individuals react optimally to their own income process but ignore economy wide information. Since individual income is less persistent than aggregate income consumers will react too little to aggregate income variation. Aggregate consumption will be excessively smooth. Since aggregate information is slowly incorporated into consumption, aggregate consumption will be autocorrelated and correlated with lagged income. The second p...

  18. Fungal farming in a non-social beetle.

    Directory of Open Access Journals (Sweden)

    Wataru Toki

    Full Text Available Culturing of microbes for food production, called cultivation mutualism, has been well-documented from eusocial and subsocial insects such as ants, termites and ambrosia beetles, but poorly described from solitary, non-social insects. Here we report a fungal farming in a non-social lizard beetle Doubledaya bucculenta (Coleoptera: Erotylidae: Languriinae, which entails development of a special female structure for fungal storage/inoculation, so-called mycangium, and also obligate dependence of the insect on the fungal associate. Adult females of D. bucculenta bore a hole on a recently-dead bamboo culm with their specialized mandibles, lay an egg into the internode cavity, and plug the hole with bamboo fibres. We found that the inner wall of the bamboo internode harboring a larva is always covered with a white fungal layer. A specific Saccharomycetes yeast, Wickerhamomyces anomalus ( = Pichia anomala, was consistently isolated from the inner wall of the bamboo internodes and also from the body surface of the larvae. Histological examination of the ovipositor of adult females revealed an exoskeletal pocket on the eighth abdominal segment. The putative mycangium contained yeast cells, and W. anomalus was repeatedly detected from the symbiotic organ. When first instar larvae were placed on culture media inoculated with W. anomalus, they grew and developed normally to adulthood. By contrast, first instar larvae placed on either sterile culture media or autoclaved strips of bamboo inner wall exhibited arrested growth at the second instar, and addition of W. anomalus to the media resumed growth and development of the larvae. These results strongly suggest a mutualistic nature of the D. bucculenta-W. anomalus association with morphological specialization and physiological dependence. Based on these results, we compare the fungal farming of D. bucculenta with those of social and subsocial insects, and discuss ecological factors relevant to the

  19. Turbulent breakage of ductile aggregates

    CERN Document Server

    Marchioli, Cristian

    2015-01-01

    In this paper we study breakage rate statistics of small colloidal aggregates in non-homogeneous anisotropic turbulence. We use pseudo-spectral direct numerical simulation of turbulent channel flow and Lagrangian tracking to follow the motion of the aggregates, modelled as sub-Kolmogorov massless particles. We focus specifically on the effects produced by ductile rupture: This rupture is initially activated when fluctuating hydrodynamic stresses exceed a critical value, $\\sigma>\\sigma_{cr}$, and is brought to completion when the energy absorbed by the aggregate meets the critical breakage value. We show that ductile rupture breakage rates are significantly reduced with respect to the case of instantaneous brittle rupture (i.e. breakage occurs as soon as $\\sigma>\\sigma_{cr}$). These discrepancies are due to the different energy values at play as well as to the statistical features of energy distribution in the anisotropic turbulence case examined.

  20. Equilibrium structure of ferrofluid aggregates

    International Nuclear Information System (INIS)

    We study the equilibrium structure of large but finite aggregates of magnetic dipoles, representing a colloidal suspension of magnetite particles in a ferrofluid. With increasing system size, the structural motif evolves from chains and rings to multi-chain and multi-ring assemblies. Very large systems form single- and multi-wall coils, tubes and scrolls. These structural changes result from a competition between various energy terms, which can be approximated analytically within a continuum model. We also study the effect of external parameters such as magnetic field on the relative stability of these structures. Our results may give insight into experimental data obtained during solidification of ferrofluid aggregates at temperatures where thermal fluctuations become negligible in comparison to inter-particle interactions. These data may also help to experimentally control the aggregation of magnetic particles.

  1. Molecular Aggregation in Disodium Cromoglycate

    Science.gov (United States)

    Singh, Gautam; Agra-Kooijman, D.; Collings, P. J.; Kumar, Satyendra

    2012-02-01

    Details of molecular aggregation in the mesophases of the anti-asthmatic drug disodium cromoglycate (DSCG) have been studied using x-ray synchrotron scattering. The results show two reflections, one at wide angles corresponding to π-π stacking (3.32 å) of molecules, and the other at small angles which is perpendicular to the direction of molecular stacking and corresponds to the distance between the molecular aggregates. The latter varies from 35 - 41 å in the nematic (N) phase and 27 -- 32 å in the columnar (M) phase. The temperature evolution of the stack height, positional order correlations in the lateral direction, and orientation order parameter were determined in the N, M, and biphasic regions. The structure of the N and M phases and the nature of the molecular aggregation, together with their dependence on temperature and concentration, will be presented.

  2. Photostimulated Aggregation of Metal Aerosols

    CERN Document Server

    Karpov, Sergei V

    2010-01-01

    The effect of optical radiation on the rate of aggregation of nanoscopic particles is studied in metal aerosols. It has been shown that under light exposure, polydisperse metal aerosols can aggregate up to two orders faster due to the size dependent photoelectron effect from nanoparticles. Different size nanoparticles undergo mutual heteropolar charging when exchanging photoelectrons through the interparticle medium to result in an increased rate of aggregation. It is shown that long-range electrostatic attractive forces drive the particles into closer distances where the short-range Van-der-Waals forces become dominating. Attention is drawn to the fact that this effect may occur in various types of dispersed systems as well as in natural heteroaerosols.

  3. Quantum Diffusion-Limited Aggregation

    CERN Document Server

    Johnson, David B

    2011-01-01

    Though classical random walks have been studied for many years, research concerning their quantum analogues, quantum random walks, has only come about recently. Numerous simulations of both types of walks have been run and analyzed, and are generally well-understood. Research pertaining to one of the more important properties of classical random walks, namely, their ability to build fractal structures in diffusion-limited aggregation, has been particularly noteworthy. However, only now has research begun in this area in regards to quantum random motion. The study of random walks and the structures they build has various applications in materials science. Since all processes are quantum in nature, it is important to consider the quantum variant of diffusion-limited aggregation. Recognizing that Schr\\"odinger equation and a classical random walk are both diffusion equations, it is possible to connect and compare them. Using similar parameters for both equations, we ran various simulations aggregating particles....

  4. Balancing energy flexibilities through aggregation

    DEFF Research Database (Denmark)

    Valsomatzis, Emmanouil; Hose, Katja; Pedersen, Torben Bach

    2014-01-01

    in both energy production and consumption, is the key to solving these problems. Flexibilities can be expressed as flex-offers, which due to their high number need to be aggregated to reduce the complexity of energy scheduling. In this paper, we discuss balance aggregation techniques that already......One of the main goals of recent developments in the Smart Grid area is to increase the use of renewable energy sources. These sources are characterized by energy fluctuations that might lead to energy imbalances and congestions in the electricity grid. Exploiting inherent flexibilities, which exist...... during aggregation aim at balancing flexibilities in production and consumption to reduce the probability of congestions and reduce the complexity of scheduling. We present results of our extensive experiments....

  5. De Novo Transcriptome and Expression Profile Analysis to Reveal Genes and Pathways Potentially Involved in Cantharidin Biosynthesis in the Blister Beetle Mylabris cichorii.

    Science.gov (United States)

    Huang, Yi; Wang, Zhongkang; Zha, Shenfang; Wang, Yu; Jiang, Wei; Liao, Yufeng; Song, Zhangyong; Qi, Zhaoran; Yin, Youping

    2016-01-01

    The dried body of Mylabris cichorii is well-known Chinese traditional medicine. The sesquiterpenoid cantharidin, which is secreted mostly by adult male beetles, has recently been used as an anti-cancer drug. However, little is known about the mechanisms of cantharidin biosynthesis. Furthermore, there is currently no genomic or transcriptomic information for M. cichorii. In this study, we performed de novo assembly transcriptome of M. cichorii using the Illumina Hiseq2000. A single run produced 9.19 Gb of clean nucleotides comprising 29,247 sequences, including 23,739 annotated sequences (about 81%). We also constructed two expression profile libraries (20-25 day-old adult males and 20-25 day-old adult females) and discovered 2,465 significantly differentially-expressed genes. Putative genes and pathways involved in the biosynthesis of cantharidin were then characterized. We also found that cantharidin biosynthesis in M. cichorii might only occur via the mevalonate (MVA) pathway, not via the methylerythritol 4-phosphate/deoxyxylulose 5-phosphate (MEP/DOXP) pathway or a mixture of these. Besides, we considered that cantharidin biosynthesis might be related to the juvenile hormone (JH) biosynthesis or degradation. The results of transcriptome and expression profiling analysis provide a comprehensive sequence resource for M. cichorii that could facilitate the in-depth study of candidate genes and pathways involved in cantharidin biosynthesis, and may thus help to improve our understanding of the mechanisms of cantharidin biosynthesis in blister beetles. PMID:26752526

  6. Learning to Facilitate (Online) Meetings

    DEFF Research Database (Denmark)

    Reimann, Peter; Bull, Susan; Vatrapu, Ravi

    2013-01-01

    We describe an approach to teaching collaboration skills directly by building on competences for meeting facilitation. (Online) meetings provide a rich arena to practice collaboration since they can serve multiple purposes: learning, problem solving, decision making, idea generation and advancement...

  7. Facilitation Skills for Library Professionals

    OpenAIRE

    O'Shea, Anne; Matheson, Laura

    2010-01-01

    Session summary: Brainstorming, problem-solving, team-building and group communication – all of these things can be made easier through facilitation! Come to this fun, interactive workshop to learn techniques and exercises to boost your group meetings. Taught by two information professionals with formal facilitation training and experience, this workshop will give you theory, hands-on practice time and feedback. What participants will learn: Participants will learn techniques to he...

  8. Studies on recycled aggregates-based concrete.

    Science.gov (United States)

    Rakshvir, Major; Barai, Sudhirkumar V

    2006-06-01

    Reduced extraction of raw materials, reduced transportation cost, improved profits, reduced environmental impact and fast-depleting reserves of conventional natural aggregates has necessitated the use of recycling, in order to be able to conserve conventional natural aggregate. In this study various physical and mechanical properties of recycled concrete aggregates were examined. Recycled concrete aggregates are different from natural aggregates and concrete made from them has specific properties. The percentages of recycled concrete aggregates were varied and it was observed that properties such as compressive strength showed a decrease of up to 10% as the percentage of recycled concrete aggregates increased. Water absorption of recycled aggregates was found to be greater than natural aggregates, and this needs to be compensated during mix design. PMID:16784165

  9. Diversity, intent, and aggregated search

    NARCIS (Netherlands)

    M. de Rijke

    2014-01-01

    Diversity, intent and aggregated search are three core retrieval concepts that receive significant attention. In search result diversification one typically considers the relevance of a document in light of other retrieved documents. The goal is to identify the probable "aspects" of an ambiguous que

  10. Child Labor and Aggregate Fluctuations

    OpenAIRE

    Stéphane Pallage; Alice Fabre

    2010-01-01

    In this paper, we build a dynamic general equilibrium model with heterogeneous agents to measure the welfare effect of banning child labor in an economy with aggregate fluctuations and idiosyncratic shocks to employment. We then design an unemployment insurance system that generates the endogenous elimination of child labor.

  11. A Complex Dance: The Importance of Glycosaminoglycans and Zinc in the Aggregation of Human Prolactin.

    Science.gov (United States)

    Christensen, Line Friis Bakmann; Malmos, Kirsten Gade; Christiansen, Gunna; Otzen, Daniel Erik

    2016-07-01

    The zinc binding hormone pituitary human prolactin (hPRL) is stored in secretory granules of specialized cells in an aggregated form. Glycosaminoglycans (GAGs) are anionic polysaccharides commonly associated with secretory granules, indicating their involvement in granule formation. Here we, for the first time, study the impact of GAGs in combination with Zn(2+) on the reversible hPRL aggregation across the pH range of 7.4-5.5. Zn(2+) alone causes hPRL aggregation at pH 7.4, while aggregation between pH 7.4 and 5.5 requires both Zn(2+) and GAGs. GAGs alone cause hPRL aggregation below pH 5.5. Comprehensive thermal stability investigations show that hPRL is particularly destabilized toward thermal denaturation at pH 5.5 and that GAGs increasingly destabilize hPRL at decreasing pH values. We propose that Zn(2+) causes hPRL aggregation through low-affinity Zn(2+) binding sites on hPRL with GAGs facilitating Zn(2+) binding by neutralizing repulsive positive charges of hPRL in the acidic environments of the TGN and mature secretory granules. In a manner independent of the aggregation-causing agent(s), the different hPRL aggregates show very similar secondary structure and amorphous morphology. We speculate that this may be a recognizable sorting signal in the formation of hPRL granular vesicles. PMID:27305175

  12. Nitrogen cycling responses to mountain pine beetle disturbance in a high elevation whitebark pine ecosystem.

    Directory of Open Access Journals (Sweden)

    Megan P Keville

    Full Text Available Ecological disturbances can significantly affect biogeochemical cycles in terrestrial ecosystems, but the biogeochemical consequences of the extensive mountain pine beetle outbreak in high elevation whitebark pine (WbP (Pinus albicaulis ecosystems of western North America have not been previously investigated. Mountain pine beetle attack has driven widespread WbP mortality, which could drive shifts in both the pools and fluxes of nitrogen (N within these ecosystems. Because N availability can limit forest regrowth, understanding how beetle-induced mortality affects N cycling in WbP stands may be critical to understanding the trajectory of ecosystem recovery. Thus, we measured above- and belowground N pools and fluxes for trees representing three different times since beetle attack, including unattacked trees. Litterfall N inputs were more than ten times higher under recently attacked trees compared to unattacked trees. Soil inorganic N concentrations also increased following beetle attack, potentially driven by a more than two-fold increase in ammonium (NH₄⁺ concentrations in the surface soil organic horizon. However, there were no significant differences in mineral soil inorganic N or soil microbial biomass N concentrations between attacked and unattacked trees, implying that short-term changes in N cycling in response to the initial stages of WbP attack were restricted to the organic horizon. Our results suggest that while mountain pine beetle attack drives a pulse of N from the canopy to the forest floor, changes in litterfall quality and quantity do not have profound effects on soil biogeochemical cycling, at least in the short-term. However, continuous observation of these important ecosystems will be crucial to determining the long-term biogeochemical effects of mountain pine beetle outbreaks.

  13. Scarab Beetle (Coleoptera: Scarabaeidae Fauna in Ardabil Province, North West Iran

    Directory of Open Access Journals (Sweden)

    G Mowlavi

    2008-12-01

    Full Text Available Background: Dung beetles of Coleoptera associated to undisturbed cattle droppings in pastures present great diver¬sity and abundance. Dung beetles also play an important role for transmission of some helminthes to human and cat¬tle. This study was made to survey the biodiversity and abundance of these beetles in Ardebil Province, western Iran.Methods: According to the field study all beetles attracted to fresh cow dung in five areas of Ardebil Province in¬cluding Namin, Ardabil, Meshkinshahr, Neer and Sarein were collected and identified. They were collected during summer 2007 from June to September, with general peaks appearing to be correlated with temperature mainly at 11 a.m to 15 p.m. The samples were identified using appropriate systematic key Results: A total of 231 specimens belonging to 9 beetle genera and at least 15 species were identified as Euoniticel¬lus fulvus, Sisyphus schaffaer, Euonthophagus taurus, Copris lunaris, Chironitis pamphilus, Gymnopleurus coriarus, Euonthophagus amyntas, Caccobius schreberi, Onthophagus speculifer, Onthophagus furcatus, Aphodius, lugens, Apho¬dius fimetarius, A. scrutator, Geotrupes spiniger and G. stercorariusThe most abundant and diverse subfamilies were Coprinae, Geotrupinae, and Aphodiinae. Conclusion: We found 15 species of dung beetles occurred in the region. The prevalence of each species is varied depending on location. Some of them play an important role for helminths transmission of veterinary and public health importance. The finding will provide a clue for pasture management as well as public health monitoring and surveillance of the disease transmitted by dung beetles

  14. Scarab Beetle (Coleoptera: Scarabaeidae Fauna in Ardabil Province, North West Iran

    Directory of Open Access Journals (Sweden)

    G Mowlavi

    2008-12-01

    Full Text Available "nBackground: Dung beetles of Coleoptera associated to undisturbed cattle droppings in pastures present great diver¬sity and abundance. Dung beetles also play an important role for transmission of some helminthes to human and cat¬tle. This study was made to survey the biodiversity and abundance of these beetles in Ardebil Province, western Iran."nMethods: According to the field study all beetles attracted to fresh cow dung in five areas of Ardebil Province in¬cluding Namin, Ardabil, Meshkinshahr, Neer and Sarein were collected and identified. They were collected during summer 2007 from June to September, with general peaks appearing to be correlated with temperature mainly at 11 a.m to 15 p.m. The samples were identified using appropriate systematic key "nResults: A total of 231 specimens belonging to 9 beetle genera and at least 15 species were identified as Euoniticel¬lus fulvus, Sisyphus schaffaer, Euonthophagus taurus, Copris lunaris, Chironitis pamphilus, Gymnopleurus coriarus, Euonthophagus amyntas, Caccobius schreberi, Onthophagus speculifer, Onthophagus furcatus, Aphodius, lugens, Apho¬dius fimetarius, A. scrutator, Geotrupes spiniger and G. stercorarius"nThe most abundant and diverse subfamilies were Coprinae, Geotrupinae, and Aphodiinae. "nConclusion: We found 15 species of dung beetles occurred in the region. The prevalence of each species is varied depending on location. Some of them play an important role for helminths transmission of veterinary and public health importance. The finding will provide a clue for pasture management as well as public health monitoring and surveillance of the disease transmitted by dung beetles

  15. Use of a Digital Image Correlation Technique for Measuring the Material Properties of Beetle Wing

    Institute of Scientific and Technical Information of China (English)

    Tailie Jin; Nam Seo Goo; Sung-Choong Woo; Hoon Cheol Park

    2009-01-01

    Beetle wings are very specialized flight organs consisting of the veins and membranes. Therefore it is necessary from a bionic view to investigate the material properties of a beetle wing experimentally. In the present study, we have used a Digital lmage Correlation (DIC) technique to measure the elastic modulus of a beetle wing membrane. Specimens were prepared by carefully cutting a beetle hind wing into 3.0 mm by 7.0 mm segments (the gage length was 5 mm). We used a scanning electron microscope for a precise measurement of the thickness of the beetle wing membrane. The specimen was attached to a designed fixture to induce a uniform displacement by means of a micromanipulator. We used an ARAMISTM system based on the digital image correlation technique to measure the corresponding displacement of a specimen. The thickness of the beetle wing varied at different points of the membrane. The elastic modulus differed in relation to the membrane arrangement showing a structural anisotropy; the elastic modulus in the chordwise direction is approximately 2.65 GPa, which is three times larger than the elastic modulus in the spanwise direction of 0.84 GPa. As a result, the digital image correlation-based ARAMIS system was suc-cessfully used to measure the elastic modulus of a beetle wing. In addition to membrane's elastic modulus, we considered the Poisson's ratio of the membrane and measured the elastic modulus of a vein using an Instron universal tensile machine. The result reveals the Poisson's ratio is nearly zero and the elastic modulus of a vein is about 11 GPa.

  16. Unintended effects of the herbicides 2,4-D and dicamba on lady beetles.

    Science.gov (United States)

    Freydier, Laurène; Lundgren, Jonathan G

    2016-08-01

    Weed resistance to glyphosate and development of new GM crops tolerant to 2,4-dichlorophenoxyacetic acid (2,4-D) and dicamba is expected to lead to increased use of these herbicides in cropland. The lady beetle, Coleomegilla maculata is an important beneficial insect in cropland that is commonly used as an indicator species in safety evaluations of pesticides. Here, we examined the lethal and non-lethal effects of 2,4-D and dicamba active ingredients and commercial formulations to this lady beetle species, and tested for synergistic effects of the herbicides. Second instars of lady beetles were exposed to an experimental treatment, and their mortality, development, weight, sex ratio, fecundity, and mobility was evaluated. Using similar methods, a dose-response study was conducted on 2,4-D with and without dicamba. The commercial formulation of 2,4-D was highly lethal to lady beetle larvae; the LC90 of this herbicide was 13 % of the label rate. In this case, the "inactive" ingredients were a key driver of the toxicity. Dicamba active ingredient significantly increased lady beetle mortality and reduced their body weight. The commercial formulations of both herbicides reduced the proportion of males in the lady beetle population. The herbicides when used together did not act synergistically in their toxicity toward lady beetles versus when the chemistries were used independently. Our work shows that herbicide formulations can cause both lethal and sublethal effects on non-target, beneficial insects, and these effects are sometimes driven by the "inactive" ingredients. The field-level implications of shifts in weed management practices on insect management programs should receive further attention. PMID:27282375

  17. Using Information Aggregation Markets for Decision Support

    Directory of Open Access Journals (Sweden)

    Patrick Buckley

    2012-06-01

    Full Text Available Information Aggregation Markets, often referred to as prediction markets, are markets that are designed to aggregate information from a disparate pool of human individuals to make predictions about the likely outcome of future uncertain events. This paper looks at how Information Aggregation Markets can be incorporated into the standard body of decision making theory. It examines how Information Aggregation Markets can be used as decision support systems, and provides empirical evidence from a wide variety of sources as to the effectiveness and practicality of Information Aggregation Markets. Finally, this paper details some future research questions to be addressed in the area of Information Aggregation Markets.

  18. Association of the symbiotic fungi Fusarium euwallaceae, Graphium sp. and Acremonium sp., with the ambrosia beetle Euwallacea nr. fornicatus in avocado

    Science.gov (United States)

    The ambrosia beetle, Euwallacea nr. fornicatus (Coleoptera:Scolytinae), is a new invasive species to Israel. To date, the beetle has been recorded from 48 tree species representing 25 plant families. Amongst the most affected are avocado, castor-bean and box elder. Isolations from beetle heads revea...

  19. Suitability of California bay laurel and other species as potential hosts for the non-native redbay ambrosia beetle and granulate ambrosia beetle

    Science.gov (United States)

    The redbay ambrosia beetle (Xyleborus glabratus Eichhoff) is a non-native invasive forest pest and vector of the pathogen that causes laurel wilt, a deadly disease of trees in the family Lauraceae in the southeastern United States (U.S.). Concern exists that X. glabratus and its fungal symbiont cou...

  20. Behavioral Ecology of Host Selection in the Asian Longhorn Beetle, Anoplophora glabripennis Motschulsky (Coleoptera: Cermabycidae): Implications for Survey, Detection and Monitoring Adult Beetles

    Science.gov (United States)

    Asian Longhorned Beetle, Anoplophora glabripennis (ALB), is among high risk invasive species that recently invaded the U.S. from China, with infestations in New York City and Long Island, NY, Chicago, IL, Jersey City, Carteret and Linden, NJ, and Toronto, Canada. ALB has attacked 25 deciduous tree s...

  1. Functional genomics and microbiome profiling of the Asian longhorned beetle (Anoplophora glabripennis) reveal insights into the digestive physiology and nutritional ecology of wood feeding beetles

    Science.gov (United States)

    The gut microbial communities associated with xylophagous beetles are taxonomically rich and predominately comprised of taxa that are poised to promote survival in woody tissue, which is devoid of nitrogen and essential nutrients. However, the contributions of gut microbes to digestive physiology a...

  2. Facilitation of learning: part 1.

    Science.gov (United States)

    Warburton, Tyler; Trish, Houghton; Barry, Debbie

    2016-04-01

    This article, the fourth in a series of 11, discusses the context for the facilitation of learning. It outlines the main principles and theories for understanding the process of learning, including examples which link these concepts to practice. The practical aspects of using these theories in a practice setting will be discussed in the fifth article of this series. Together, these two articles will provide mentors and practice teachers with knowledge of the learning process, which will enable them to meet the second domain of the Nursing and Midwifery Council's Standards to Support Learning and Assessment in Practice on facilitation of learning. PMID:27050014

  3. Leptographium tereforme sp. nov. and other Ophiostomatales isolated from the root-feeding bark beetle, Hylurgus ligniperda, in California

    Science.gov (United States)

    The redhaired pine bark beetle, Hylurgus ligniperda F., is native to Europe but was discovered in Los Angeles, California in 2003. This root- and stump-feeding bark beetle is a common vector of Ophiostomatales, which are potential tree pathogens or causes of blue-stain of conifer sapwood. In this st...

  4. Fusarium symbionts of an ambrosia beetle (Euwallacea sp.) in southern Florida are pathogens of avocado, Persea americana

    Science.gov (United States)

    Fusarium dieback, a destructive disease of avocado (Persea americana), was reported in California and Israel in 2012. It is associated with an ambrosia beetle, Euwallacea sp., and damage caused by an unnamed symbiont of the beetle in Clade 3 of the Fusarium solani species complex (FSSC) designated p...

  5. 甲壳虫是怎么得到颜色的%How Beetle Got Her Colors

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Long ago in the Amazon rain forest Beetle was just plain brown.In this same forest there lived a rat that used to tease other small animals and insects that lived there.Best of all she liked to torment the beetle.Rat had a gang of other small animals who followed her,and laughed at her mean jokes.

  6. Efficacy and longevity of essential oil lures for capture of the redbay ambrosia beetle Xyleborus glabratus (Coleoptera: Curculionidae: Scolytinae)

    Science.gov (United States)

    The redbay ambrosia beetle Xyleborus glabratus Eichhoff is an exotic wood-boring pest native to southeastern Asia. It carries a symbiotic fungus (Raffaelea lauricola) that causes laurel wilt, a lethal vascular disease of trees in the Lauraceae. First detected in Georgia in 2002, the beetle has spre...

  7. Microsatellite analysis of the Genetic Diversity of Asian Longhorned Beetles from an Invasive Population in Ontario, Canada

    Science.gov (United States)

    Asian Longhorned Beetles (Anoplophora glabripennis Motschulsky) were discovered in Ontario, Canada in 2003 at a commercial warehouse site, where they likely arrived on solid wood packing materials from China. Trees in the area were heavily scarred with oviposition sites, and larvae and adult beetle...

  8. Walking to survive. Searching, feeding and egg production of the carabid beetle Pterostichus coerulescens L. (= Poecilus versicolor Sturm).

    NARCIS (Netherlands)

    Mols, P.J.M.

    1993-01-01

    This study concerns the prey-searching and feeding behaviour of the polyphagous groundbeetle Pterostichus coerulescens L. ( = Poecilus versicolor Sturm), a common species on sandy soils. This ground beetle rarely flies, thus preysearching behaviour involves walking. The beetle is diurnal. As object

  9. Performance of a Beetle 1.2 chip reading out a Micron PR03 R measuring sensor

    CERN Document Server

    Buytaert, J; Eckstein, D; Palacios, J P

    2004-01-01

    The performance of a Beetle 1.2 chip bonded to a Micron PR03 measuring prototype VELO sensor has been studied using test beam data collected by the VELO group. Results concerning the peak signal, signal to noise ratio, signal remainder 25 ns after peaking time, and a scan of the undershoot region for different bias settings of the Beetle are presented.

  10. Draft Genome Sequence of Raffaelea quercivora JCM 11526, a Japanese Oak Wilt Pathogen Associated with the Platypodid Beetle, Platypus quercivorus

    Science.gov (United States)

    Manabe, Ri-ichiroh; Ohkuma, Moriya; Endoh, Rikiya

    2016-01-01

    The Japanese oak wilt pathogen Raffaelea quercivora and the platypodid beetle, Platypus quercivorus, cause serious mass mortality of Quercus spp. in Japan. Here, we present the first draft genome sequence of R. quercivora JCM 11526 to increase our understanding of the mechanism of pathogenicity and symbiosis with the ambrosia beetle. PMID:27469944

  11. Cloning and characterization of an MRNA encoding an insulin receptor from the horned scarab beetle Onthophagus nigriventris (Coleoptera: scarabaeidae)

    Science.gov (United States)

    The insulin signaling pathway has been implicated in the control of insect polyphenisms for some caste-forming insects and potentially has a role in horn dimorphisms in beetles. Males of the sexually dimorphic dung beetle Onthophagus nigriventris develop a magnificent thoracic horn up to twice the l...

  12. Redbay ambrosia beetle/Laurel wilt: Overview of projects at the USDA-ARS Subtropical Horticulture Research Station

    Science.gov (United States)

    ABSTRACT Laurel wilt, a deadly fungal disease of avocado and other trees in the Lauraceae, is vectored by the redbay ambrosia beetle (Xyleborus glabratus). First detected near Savannah, GA in 2002, the beetle and its obligatory pathogen have since spread to South Carolina and Florida. Currently, t...

  13. Fusarium euwallaceae, a novel species cultivated by a Euwallacea ambrosia beetle that threatens avocado production in Israel and California

    Science.gov (United States)

    Avocado production in Israel and California, USA is facing a serious threat due to damage caused by an invasive Euwallacea ambrosia beetle and a novel Fusarium that it cultivates as a source of food. Adult female beetles possess mandibular mycangia within which they carry the Fusarium symbiont. At l...

  14. Management for Mountain Pine Beetle Outbreak Suppression: Does Relevant Science Support Current Policy?

    Directory of Open Access Journals (Sweden)

    Diana L. Six

    2014-01-01

    Full Text Available While the use of timber harvests is generally accepted as an effective approach to controlling bark beetles during outbreaks, in reality there has been a dearth of monitoring to assess outcomes, and failures are often not reported. Additionally, few studies have focused on how these treatments affect forest structure and function over the long term, or our forests’ ability to adapt to climate change. Despite this, there is a widespread belief in the policy arena that timber harvesting is an effective and necessary tool to address beetle infestations. That belief has led to numerous proposals for, and enactment of, significant changes in federal environmental laws to encourage more timber harvests for beetle control. In this review, we use mountain pine beetle as an exemplar to critically evaluate the state of science behind the use of timber harvest treatments for bark beetle suppression during outbreaks. It is our hope that this review will stimulate research to fill important gaps and to help guide the development of policy and management firmly based in science, and thus, more likely to aid in forest conservation, reduce financial waste, and bolster public trust in public agency decision-making and practice.

  15. Associations of Conifer-Infesting Bark Beetles and Fungi in Fennoscandia

    Directory of Open Access Journals (Sweden)

    Michael J. Wingfield

    2012-02-01

    Full Text Available Bark beetles (Coleoptera, Scolytinae have a widespread association with fungi, especially with ophiostomatoid fungi (Ascomycota that cause blue staining of wood, and in some cases, serious tree diseases. In Fennoscandia, most studies of these fungi have focused on economically important bark beetle species and this is likely to have led to a biased view of the fungal biodiversity in the region. Recently, the associations between fungi and bark beetles in Fennoscandia have been shown to be more diverse than previously thought. Furthermore, they form complex and dynamic associations that are only now beginning to emerge. This review examines the current knowledge of the rather poorly known interactions between bark beetles, fungi and their conifer host trees in Fennoscandia. The diversity of ophiostomatoid species is discussed and the possible factors that influence the assemblages of fungal associates are considered for all species that are known to occur in the region. For many ophiostomatoid species found in Fennoscandia, little or nothing is known regarding their pathogenicity, particularly if they were to be transferred to new environments. We, therefore, draw attention to the possible threats of timber trade and climate change-induced invasions of new habitats by bark beetles and the fungi that can be moved along with them.

  16. Recalibrated tree of leaf beetles (Chrysomelidae indicates independent diversification of angiosperms and their insect herbivores.

    Directory of Open Access Journals (Sweden)

    Jesús Gómez-Zurita

    Full Text Available BACKGROUND: The great diversity of the "Phytophaga" (weevils, longhorn beetles and leaf beetles has been attributed to their co-radiation with the angiosperms based on matching age estimates for both groups, but phylogenetic information and molecular clock calibrations remain insufficient for this conclusion. METHODOLOGY: A phylogenetic analysis of the leaf beetles (Chrysomelidae was conducted based on three partial ribosomal gene markers (mitochondrial rrnL, nuclear small and large subunit rRNA including over 3000 bp for 167 taxa representing most major chrysomelid lineages and outgroups. Molecular clock calibrations and confidence intervals were based on paleontological data from the oldest (K-T boundary leaf beetle fossil, ancient feeding traces ascribed to hispoid Cassidinae, and the vicariant split of Nearctic and Palearctic members of the Timarchini. PRINCIPAL FINDINGS: The origin of the Chrysomelidae was dated to 73-79 Mya (confidence interval 63-86 Mya, and most subfamilies were post-Cretaceous, consistent with the ages of all confirmed body fossils. Two major monocot feeding chrysomelid lineages formed widely separated clades, demonstrating independent colonization of this ancient (early Cretaceous angiosperm lineage. CONCLUSIONS: Previous calibrations proposing a much older origin of Chrysomelidae were not supported. Therefore, chrysomelid beetles likely radiated long after the origin of their host lineages and their diversification was driven by repeated radiaton on a pre-existing diverse resource, rather than ancient host associations.

  17. Beetle adhesive hairs differ in stiffness and stickiness: in vivo adhesion measurements on individual setae

    Science.gov (United States)

    Bullock, James M. R.; Federle, Walter

    2011-05-01

    Leaf beetles are able to climb on smooth and rough surfaces using arrays of micron-sized adhesive hairs (setae) of varying morphology. We report the first in vivo adhesive force measurements of individual setae in the beetle Gastrophysa viridula, using a smooth polystyrene substrate attached to a glass capillary micro-cantilever. The beetles possess three distinct adhesive pads on each leg which differ in function and setal morphology. Visualisation of pull-offs allowed forces to be measured for each tarsal hair type. Male discoidal hairs adhered with the highest forces (919 ± 104 nN, mean ± SE), followed by spatulate (582 ± 59 nN) and pointed (127 ± 19 nN) hairs. Discoidal hairs were stiffer in the normal direction (0.693 ± 0.111 N m-1) than spatulate (0.364 ± 0.039 N m-1) or pointed (0.192 ± 0.044 N m-1) hairs. The greater adhesion on smooth surfaces and the higher stability of discoidal hairs help male beetles to achieve strong adhesion on the elytra of females during copulation. A comparison of pull-off forces measured for single setae and whole pads (arrays) revealed comparable levels of adhesive stress. This suggests that beetles are able to achieve equal load sharing across their adhesive pads so that detachment through peeling is prevented.

  18. Dung beetles eat acorns to increase their ovarian development and thermal tolerance.

    Directory of Open Access Journals (Sweden)

    José R Verdú

    Full Text Available Animals eat different foods in proportions that yield a more favorable balance of nutrients. Despite known examples of these behaviors across different taxa, their ecological and physiological benefits remain unclear. We identified a surprising dietary shift that confers ecophysiological advantages in a dung beetle species. Thorectes lusitanicus, a Mediterranean ecosystem species adapted to eat semi-dry and dry dung (dung-fiber consumers is also actively attracted to oak acorns, consuming and burying them. Acorn consumption appears to confer potential advantages over beetles that do not eat acorns: acorn-fed beetles showed important improvements in the fat body mass, hemolymph composition, and ovary development. During the reproductive period (October-December beetles incorporating acorns into their diets should have greatly improved resistance to low-temperature conditions and improved ovarian development. In addition to enhancing the understanding of the relevance of dietary plasticity to the evolutionary biology of dung beetles, these results open the way to a more general understanding of the ecophysiological implications of differential dietary selection on the ecology and biogeography of these insects.

  19. Genetic Structure of Water Chestnut Beetle: Providing Evidence for Origin of Water Chestnut.

    Science.gov (United States)

    Tang, Xiao-Tian; Zheng, Fu-Shan; Qin, Jing; Lu, Ming-Xing; Du, Yu-Zhou

    2016-01-01

    Water chestnut beetle (Galerucella birmanica Jacoby) is a pest of the water chestnut (Trapa natans L.). To analyze the phylogeny and biogeography of the beetle and provide evidence for the origin of T. natans in China, we conducted this by using three mitochondrial genes (COI, COII and Cytb) and nuclear ITS2 ribosomal DNA of G. birmanica. As for mtDNA genes, the beetle could be subdivided into three groups: northeastern China (NEC), central-northern-southern China (CC-NC-SC) and southwestern China (SWC) based on SAMOVA, phylogenetic analyses and haplotype networks. But for ITS2, no obvious lineages were obtained but individuals which were from NEC region clustered into one clade, which might be due to sequence conservation of ITS2. Significant genetic variation was observed among the three groups with infrequent gene flow between groups, which may have been restricted due to natural barriers and events in the Late Pleistocene. Based on our analyses of genetic variation in the CC-NC-SC geographical region, the star-like haplotype networks, approximate Bayesian computation, niche modelling and phylogeographic variation of the beetle, we concluded that the beetle population has been lasting in the lower, central reaches of the Yangtze River Basin with its host plant, water chestnut, which is consistent with archaeological records. Moreover, we speculate that the CC-NC-SC population of G. birmanica may have undergone a period of expansion coincident with domestication of the water chestnut approximately 113,900-126,500 years ago. PMID:27459279

  20. Genetic Structure of Water Chestnut Beetle: Providing Evidence for Origin of Water Chestnut.

    Directory of Open Access Journals (Sweden)

    Xiao-Tian Tang

    Full Text Available Water chestnut beetle (Galerucella birmanica Jacoby is a pest of the water chestnut (Trapa natans L.. To analyze the phylogeny and biogeography of the beetle and provide evidence for the origin of T. natans in China, we conducted this by using three mitochondrial genes (COI, COII and Cytb and nuclear ITS2 ribosomal DNA of G. birmanica. As for mtDNA genes, the beetle could be subdivided into three groups: northeastern China (NEC, central-northern-southern China (CC-NC-SC and southwestern China (SWC based on SAMOVA, phylogenetic analyses and haplotype networks. But for ITS2, no obvious lineages were obtained but individuals which were from NEC region clustered into one clade, which might be due to sequence conservation of ITS2. Significant genetic variation was observed among the three groups with infrequent gene flow between groups, which may have been restricted due to natural barriers and events in the Late Pleistocene. Based on our analyses of genetic variation in the CC-NC-SC geographical region, the star-like haplotype networks, approximate Bayesian computation, niche modelling and phylogeographic variation of the beetle, we concluded that the beetle population has been lasting in the lower, central reaches of the Yangtze River Basin with its host plant, water chestnut, which is consistent with archaeological records. Moreover, we speculate that the CC-NC-SC population of G. birmanica may have undergone a period of expansion coincident with domestication of the water chestnut approximately 113,900-126,500 years ago.

  1. Novel antennal lobe substructures revealed in the small hive beetle Aethina tumida.

    Science.gov (United States)

    Kollmann, Martin; Rupenthal, Anna Lena; Neumann, Peter; Huetteroth, Wolf; Schachtner, Joachim

    2016-03-01

    The small hive beetle, Aethina tumida, is an emerging pest of social bee colonies. A. tumida shows a specialized life style for which olfaction seems to play a crucial role. To better understand the olfactory system of the beetle, we used immunohistochemistry and 3-D reconstruction to analyze brain structures, especially the paired antennal lobes (AL), which represent the first integration centers for odor information in the insect brain. The basic neuroarchitecture of the A. tumida brain compares well to the typical beetle and insect brain. In comparison to other insects, the AL are relatively large in relationship to other brain areas, suggesting that olfaction is of major importance for the beetle. The AL of both sexes contain about 70 olfactory glomeruli with no obvious size differences of the glomeruli between sexes. Similar to all other insects including beetles, immunostaining with an antiserum against serotonin revealed a large cell that projects from one AL to the contralateral AL to densely innervate all glomeruli. Immunostaining with an antiserum against tachykinin-related peptides (TKRP) revealed hitherto unknown structures in the AL. Small TKRP-immunoreactive spherical substructures are in both sexes evenly distributed within all glomeruli. The source for these immunoreactive islets is very likely a group of about 80 local AL interneurons. We offer two hypotheses on the function of such structures. PMID:26496732

  2. The tiger beetles (Coleoptera, Carabidae, Cicindelinae) of Israel and adjacent lands

    Science.gov (United States)

    Matalin, Andrey V.; Chikatunov, Vladimir I.

    2016-01-01

    Abstract Based on field studies, museums collections and literature sources, the current knowledge of the tiger beetle fauna of Israel and adjacent lands is presented. In Israel eight species occur, one of them with two subspecies, while in the Sinai Peninsula nine species of tiger beetles are now known. In the combined regions seven genera from two tribes were found. The Rift Valley with six cicindelids species is the most specious region of Israel. Cylindera contorta valdenbergi and Cicindela javeti azari have localized distributions and should be considered regional endemics. A similarity analysis of the tiger beetles faunas of different regions of Israel and the Sinai Peninsula reveal two clusters of species. The first includes the Great Rift Valley and most parts of the Sinai Peninsula, and the second incorporates most regions of Israel together with Central Sinai Foothills. Five distinct adult phenological groups of tiger beetles can be distinguished in these two clusters: active all-year (three species), spring-fall (five species), summer (two species), spring-summer (one species) and spring (one species). The likely origins of the tiger beetle fauna of this area are presented. An annotated list and illustrated identification key of the Cicindelinae of Israel and adjacent lands are provided. PMID:27110198

  3. Susceptibility of brassicaceous plants to feeding by flea beetles, Phyllotreta spp. (Coleoptera: Chrysomelidae).

    Science.gov (United States)

    Soroka, Juliana; Grenkow, Larry

    2013-12-01

    Crucifer-feeding flea beetles, Phyllotreta spp., are chronic insect pests in Canadian prairie canola production. Multiple laboratory and field feeding bioassays were conducted to determine the susceptibility of a wide range of crucifer species, cultivars, and accessions to feeding by flea beetles with the goal of discovering sources of resistant germplasm. In 62 bioassays of 218 entries, no consistent decreased feeding by flea beetles was seen on any entries of Brassica carinata A. Braun, Brassica juncea (L.) Czern., Brassica napus L., or Brassica rapa L. There was reduced feeding on condiment mustard Sinapis alba L. lines but not on canola-quality lines with reduced amounts of glucosinolates, which were fed on at levels equal to B. napus. Analyses of glucosinolate content found decreased quantities of hydroxybenzyl and butyl glucosinolates in preferred canola-quality S. alba lines and increased levels of hydroxybutenyl glucosinolates compared with levels in condiment S. alba lines. Eruca sativa Mill. was an excellent flea beetle host; Camelina sativa (L.) Crantz lines experienced little feeding. Lines of Crambe abyssinica Hochst. ex R. E. Fries and Crambe hispanica L. had reduced feeding levels compared with Brassica entries, but Crambe glabrata DC did not. The results indicate possible sources of resistance to Phyllotreta flea beetles, while highlighting the complicated roles that glucosinolates may play in Phyllotreta host preference. PMID:24498758

  4. Estimation of line efficiency by aggregation

    OpenAIRE

    Koster, de, MBM René

    1987-01-01

    textabstractPresents a multi-stage flow lines with intermediate buffers approximated by two-stage lines using repeated aggregation. Characteristics of the aggregation method; Problems associated with the analysis and design of production lines.

  5. Aggregation of metallochlorophylls - Examination by spectroscopy

    Science.gov (United States)

    Boucher, L. J.; Katz, J. J.

    1969-01-01

    Nuclear magnetic resonance measurements determine which metallochlorophylls, besides magnesium-containing chlorophylls, possess coordination aggregation properties. Infrared spectroscopy reveals that only zinc pheophytin and zinc methyl pheophorbide showed significant coordination aggregation, whereas divalent nickel and copper did not.

  6. Yeast prions: protein aggregation is not enough.

    OpenAIRE

    Sherman, Michael Y

    2004-01-01

    Although many proteins -- both damaged and normal -- have a tendency to aggregate, only some are capable of dividing and propagating. What does it take to turn a protein aggregate into an infectious prion?

  7. Estimation of Line Efficiency by Aggregation

    NARCIS (Netherlands)

    M.B.M. de Koster (René)

    1987-01-01

    textabstractPresents a multi-stage flow lines with intermediate buffers approximated by two-stage lines using repeated aggregation. Characteristics of the aggregation method; Problems associated with the analysis and design of production lines.

  8. Elections, information aggregation, and strategic voting

    OpenAIRE

    Feddersen, Timothy; Pesendorfer, Wolfgang

    1999-01-01

    A central role of elections is the aggregation of information dispersed within a population. This article surveys recent work on elections as mechanisms for aggregating information and on the incentives for voters to vote strategically in such elections.

  9. Bacterial Association with Particles: Aggregation to Dissolution

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza, M.J.B.D.

    stick to phytoplankton cells to form larger particles called marine snow that enhance the sinking flux of organic carbon. However, Smith et al. (1992) and Ploug et al. (1999) found that once the bacteria colonize the aggregate they solubilize... trophic levels of the aquatic food web (Kiorboe et al., 2002). Caron et al. (1982) thought that aggregates are important loci of microbial activity in the water column, similar to the much larger oceanic ?marine snow? aggregates. Marine snow aggregates...

  10. ASSESSMENT OF FINE RECYCLED AGGREGATES IN MORTAR

    OpenAIRE

    Feys, Charles; Joseph, Miquel; Boehme, Luc; Zhang, Yunlian

    2016-01-01

    In this study, the influence of fine recycled concrete aggregates as replacement for sand in mortar and the use as cement replacement and filler is investigated. Mortar with fine recycled aggregates is examined on its mechanical and physical properties. The samples are also examined on a microscopic scale. The fine recycled concrete aggregates are made with one-year old concrete made in the laboratory. Fine recycled aggregates (FRCA) are added as a cement replacement (0 %, 10 %...

  11. Revisiting Aggregation Techniques for Data Intensive Applications

    OpenAIRE

    Wen, Jian

    2013-01-01

    Aggregation has been an important operation since the early days of relational databases. Today's Big Data applications bring further challenges when processing aggregation queries, demanding robust aggregation algorithms that can process large volumes of data efficiently in a distributed, share-nothing architecture. Moreover, aggregation on each node runs under a potentially limited memory budget (especially in multiuser settings). Despite its importance, the design and evaluation of aggrega...

  12. Computers and Productivity: Are Aggregation Effects Important?

    OpenAIRE

    Robert H. McGuckin; Kevin Stiroh

    2000-01-01

    This paper examines the empirical implications of aggregation bias when measuring the productive impact of computers. To isolate two specific aggregation problems relating to "aggregation in variables" and "aggregation in relations," we compare various production function estimates across a range of specifications, econometric estimators, and data levels. The results show that both sources of bias are important, especially as one moves from the sector to the economy level, and when the elasti...

  13. Internal water curing with Liapor aggregates

    DEFF Research Database (Denmark)

    Lura, Pietro

    2005-01-01

    Internal water curing is a very efficient way to counteract self-desiccation and autogenous shrinkage in high performance concrete, thereby reducing the likelihood of early-age cracking. This paper deals with early-age volume changes and moisture transport in lightweight aggregate concrete realized...... with wet lightweight aggregates. Lightweight aggregate concrete mixtures with different degree of saturation and different particle size of the lightweight aggregates were studied and compared to normal weight concrete. Autogenous deformations, selfinduced stresses in fully restrained conditions...

  14. Aggregation resistant zwitterated superparamagnetic nanoparticles

    International Nuclear Information System (INIS)

    Superparamagnetic nanoparticles (NPs) are promising for biomedical applications since they can be directed toward the organ of interest using an external magnetic field. They are also good contrast agents for magnetic resonance imaging and have potential for the treatment of malignant tumors (i.e., hyperthermia). Therefore, there is a need to produce stable, non-aggregating superparamagnetic nanomaterials that can withstand the in vivo environment. In this work, the colloidal stability of a dispersion of iron oxide NPs was enhanced by functionalizing them with a short zwitterionic siloxane shell in aqueous media. The stabilization procedure yields superparamagnetic nanomaterials, ca. 10 nm in diameter, with saturation magnetization of about 54 emu/g that resist aggregation at physiological salt concentration, temperature, and pH. The loading of the zwitterionic shell was established with diffuse reflectance infrared spectroscopy and thermal gravimetric analysis. X-ray and electron diffraction verified the starting magnetite phase, and that no change in phase occurred on surface functionalization.

  15. Aggregating and Disaggregating Flexibility Objects

    DEFF Research Database (Denmark)

    Siksnys, Laurynas; Valsomatzis, Emmanouil; Hose, Katja;

    2015-01-01

    In many scientific and commercial domains we encounter flexibility objects, i.e., objects with explicit flexibilities in a time and an amount dimension (e.g., energy or product amount). Applications of flexibility objects require novel and efficient techniques capable of handling large amounts...... of such objects while preserving flexibility. Hence, this paper formally defines the concept of flexibility objects (flex-objects) and provides a novel and efficient solution for aggregating and disaggregating flex-objects. Out of the broad range of possible applications, this paper will focus on smart grid...... energy data management and discuss strategies for aggregation and disaggregation of flex-objects while retaining flexibility. This paper further extends these approaches beyond flex-objects originating from energy consumption by additionally considering flex-objects originating from energy production...

  16. Containing Internal Diffusion Limited Aggregation

    CERN Document Server

    Duminil-Copin, Hugo; Yadin, Ariel; Yehudayoff, Amir

    2011-01-01

    Internal Diffusion Limited Aggregation (IDLA) is a model that describes the growth of a random aggregate of particles from the inside out. Shellef proved that IDLA processes on supercritical percolation clusters of integer-lattices fill Euclidean balls, with high probability. In this article, we complete the picture and prove a limit-shape theorem for IDLA on such percolation clusters, by providing the corresponding upper bound. The technique to prove upper bounds is new and robust: it only requires the existence of a "good" lower bound. Specifically, this way of proving upper bounds on IDLA clusters is more suitable for random environments than previous ways, since it does not harness harmonic measure estimates.

  17. Spatial-temporal modeling of forest gaps generated by colonization from below- and above-ground bark beetle species

    DEFF Research Database (Denmark)

    Zhu, Jun; Rasmussen, Jakob Gulddahl; Møller, Jesper;

    2008-01-01

    Studies of forest declines are important, because they both reduce timber production and affect successional trajectories of landscapes and ecosystems. Of particular interest is the decline of red pines, which is characterized by expanding areas of dead and chlorotic trees in plantations throughout...... the Great Lakes region. Here we examine the impact of two bark beetle groups, red turpentine beetles and pine engraver bark beetles, on tree mortality and the subsequent gap formation over time in a plantation in Wisconsin. We construct spatial-temporal statistical models that quantify the relations...... among red turpentine beetle colonization, pine engraver bark beetle colonization, and mortality of red pine trees while accounting for correlation across space and over time. We extend traditional Markov random-field models to include temporal terms and multiple-response variables aimed at developing a...

  18. Spatial-temporal modeling of forest gaps generated by colonization from below- and above-ground beetle species

    DEFF Research Database (Denmark)

    Zhu, J.; Rasmussen, Jakob Gulddahl; Møller, Jesper;

    Studies of forest declines are important, because they both reduce timber production and aect successional trajectories of landscapes and ecosystems. Of partic- ular interest is the decline of red pines which is characterized by expanding areas of dead and chlorotic trees in plantations throughout...... the Great Lakes Region. Here we examine the impact of two bark beetle groups, namely red turpentine beetles and pine engraver bark beetles, on tree mortality and the subsequent gap formation over time in a plantation in Wisconsin. We construct spatial-temporal statistical models that quantify the...... relations among red turpentine beetle coloniza- tion, pine engraver bark beetle colonization, and mortality of red pine trees, while accounting for correlation across space and over time. For statistical inference, we adopt a Bayesian hierarchical model and devise Markov chain Monte Carlo algorithms for...

  19. Water beetle distribution along a perennial distance gradient in an intermittent stream from the Mediterranean part of Montenegro

    Directory of Open Access Journals (Sweden)

    Pavićević Ana

    2012-01-01

    Full Text Available In this study, we examined the impact of an unstable hydrological regime (floods and seasonal drying on water beetle fauna after a drought period, in an intermittent stream in the Mediterranean part of Montenegro. Aquatic beetles were collected between November 2009 and May 2010 from three intermittent sites along the Rimanić stream at different distances from the perennial part (DP, using quantitative sampling methods. We predicted that water beetle assemblages would vary in structure and composition along DP gradients. Total abundance, taxa richness, main faunal groups and proportion of adults and larvae were assessed in order to describe the changes in the water beetle assemblages. The water beetle fauna in the studied sites recovered slowly from the drought periods in terms of both total abundance and taxa richness. Analysis of similarity (ANOSIM showed no significant changes in community structure between the sites, but revealed changes in terms of date (Rho = 0.403.

  20. Recycled aggregate concrete; an overview

    OpenAIRE

    Sorato, Renan

    2016-01-01

    The aim of this Bachelor’s thesis was to investigate whether recycled materials can be incorporated into the production of concrete without compromising the compressive strength of the concrete produced. In order to shed light on the compressive strength of concrete made from recycled materials, the thesis reviewed studies in which waste materials are utilised as recycled aggregates in the composition of concrete and presented the results of this synthesis and analysis. It was found that som...

  1. Judgment aggregation functions and ultraproducts

    OpenAIRE

    Herzberg, Frederik

    2011-01-01

    The relationship between propositional model theory and social decision making via premise-based procedures is explored. A one-to-one correspondence between ultrafilters on the population set and weakly universal, unanimity-respecting, systematic judgment aggregation functions is established. The proof constructs an ultraproduct of profiles, viewed as propositional structures, with respect to the ultrafilter of decisive coalitions. This representation theorem can be used to prove other proper...

  2. Underground economy and aggregate fluctuations

    OpenAIRE

    Juan Carlos Conesa Roca; Carlos Díaz Moreno; José Enrique Galdón Sánchez

    2001-01-01

    This paper explores the role of underground economic activities as an explanation of differences in registered aggregate fluctuations. In order to do so, we introduce an underground economy sector in an otherwise standard Real Business Cycle model and calibrate it to the USA economy. We find that, at low frequencies, Europe fluctuates more than the USA, while its participation rate is smaller. The existence of underground activities rationalizes the negative relationship between participation...

  3. Credit contagion and aggregate losses

    OpenAIRE

    Giesecke, Kay; Weber, Stefan

    2002-01-01

    Credit contagion refers to the propagation of economic distress from one firm or sovereign government to another. In this paper we model credit contagion phenomena and study the fluctuation of aggregate credit losses on large portfolios of financial positions. The joint dynamics of firms’ credit ratings is modeled by a voter process, which is well-known in the theory of interacting particle systems. We clarify the structure of the equilibrium joint rating distribution using ergodic decomposit...

  4. Aggregating Labels in Crowdsourcing Data

    OpenAIRE

    Priisalu, Maria; Grey, Francois; Segal, Ben

    2015-01-01

    Project Specification Crowdsourcing is gaining popularity in academia with the launch of crowdsourcing platforms such as Crowdcrafting [Lombraña, 2015] and GeoTagX [UNOSAT, 2015]. There have been a number of proposed algorithms for the aggregation of true labels and a confusion matrix from crowdsourced labels for ordinal, nominal and binary labels. The work here consists of an implementation of the Dawid Skene [Dawid 1979] adaptation of the Expectation Maximization algorithm [D...

  5. Protein aggregates in Huntington's disease

    OpenAIRE

    Arrasate, M.; Finkbeiner, S

    2011-01-01

    Huntington's disease (HD) is an incurable neurodegenerative disease characterized by abnormal motor movements, personality changes, and early death. HD is caused by a mutation in the IT-15 gene that expands abnormally the number of CAG nucleotide repeats. As a result, the translated protein huntingtin contains disease-causing expansions of glutamines (polyQ) that make it prone to misfold and aggregate. While the gene and mutations that cause HD are known, the mechanisms underlying HD pathogen...

  6. Intuitionistic fuzzy aggregation and clustering

    CERN Document Server

    Xu, Zeshui

    2012-01-01

    This book offers a systematic introduction to the clustering algorithms for intuitionistic fuzzy values, the latest research results in intuitionistic fuzzy aggregation techniques, the extended results in interval-valued intuitionistic fuzzy environments, and their applications in multi-attribute decision making, such as supply chain management, military system performance evaluation, project management, venture capital, information system selection, building materials classification, and operational plan assessment, etc.

  7. Belt conveyor for recycle aggregate

    OpenAIRE

    Bezrodný, Roman

    2014-01-01

    This bachelor thesis deals with the belt conveyor for the transport of recycled aggregate in an oblique direction. The aim is to find constructional solutions to the belt conveyor for the assigned transport capacity of 95 000 kg per hour, and the assigned axial distance of 49 m and different height of 12 m. The thesis contains a brief description of the belt conveyor and a description of basic constructional components. It also contains a functional calculation of the capacity and forces acco...

  8. Aggregate Uncertainty, Money and Banking

    OpenAIRE

    Hongfei Sun

    2006-01-01

    This paper studies the problem of monitoring the monitor in a model of money and banking with aggregate uncertainty. It shows that when inside money is required as a means of bank loan repayment, a market of inside money is entailed at the repayment stage and generates information-revealing prices that perfectly discipline the bank. The incentive problem of a bank is costlessly overcome simply by involving inside money in repayment. Inside money distinguishes itself from outside money by its ...

  9. Economic Instability and Aggregate Investment

    OpenAIRE

    Robert S. Pindyck; Solimano, Andres

    1993-01-01

    Recent literature suggests that because investment expenditures are irreversible and can be delayed, they may be highly sensitive to uncertainty. The authors briefly summarize the theory, stressing its empirical implications. Then, using cross-section and time-series data for a set of developing and industrial countries, they explore the empirical relevance of irreversibility and uncertainty to aggregate investment. They find that: (a) the volatility of the marginal profitability of capital (...

  10. Parametric characterization of aggregation functions

    Czech Academy of Sciences Publication Activity Database

    Mesiar, Radko; Kolesárová, A.

    2009-01-01

    Roč. 160, č. 6 (2009), s. 816-831. ISSN 0165-0114 R&D Projects: GA ČR GA402/08/0618 Institutional research plan: CEZ:AV0Z10750506 Keywords : Aggregation function * Conjunction measure * Disjunction measure * Global/local parametric characterization * Idempotency measure Subject RIV: BA - General Mathematics Impact factor: 2.138, year: 2009 http://library.utia.cas.cz/separaty/2009/E/mesiar-parametriccharacterizationofaggregationfunctions.pdf

  11. 78 FR 68945 - Aggregation of Positions

    Science.gov (United States)

    2013-11-15

    ... (``1979 Aggregation Policy''), 44 FR 33839, 33843 (June 13, 1979). Note, however, that consistent with the... the ownership criteria of aggregation. \\40\\ See, e.g., 53 FR 13290, 13292 (1988) (proposal). The 1988... approach best resolves those issues while maintaining a bright-line aggregation test? \\41\\ See 77 FR...

  12. Aggregation functions: an approach using copulae

    OpenAIRE

    Marta Cardin; Maddalena Manzi

    2007-01-01

    In this paper we present the extension of the copula approach to aggregation functions. In fact we want to focus on a class of aggregation functions and present them in the multilinear form with marginal copulae. Moreover, we define the joint aggregation density function.

  13. 28 CFR 2.5 - Sentence aggregation.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Sentence aggregation. 2.5 Section 2.5 Judicial Administration DEPARTMENT OF JUSTICE PAROLE, RELEASE, SUPERVISION AND RECOMMITMENT OF PRISONERS... aggregation. When multiple sentences are aggregated by the Bureau of Prisons pursuant to 18 U.S.C. 4161...

  14. Aggregated Authentication (AMAC) Using Universal Hash Functions

    Science.gov (United States)

    Znaidi, Wassim; Minier, Marine; Lauradoux, Cédric

    Aggregation is a very important issue to reduce the energy consumption in Wireless Sensors Networks (WSNs). There is currently a lack of cryptographic primitives for authentication of aggregated data. The theoretical background for Aggregated Message Authentication Codes (AMACs) has been proposed by Chan and Castelluccia at ISIT 08.

  15. Aggregation of erythrocytes in burn disease

    OpenAIRE

    Levin, Grigory Y; Egorihina, Marpha N

    2011-01-01

    The manuscript describes experiments designed to examine factors that influence erythrocytes aggregation within the blood of burn patients. Results showed that the rate and degree of erythrocytes aggregation increased significantly in burn patients, and what is especially unfavorable for microcirculation, erythrocytes disaggregation decreased. We show that normalization of blood plasma contents completely restores erythrocytes aggregation and disaggregation of burn patients. The rate and degr...

  16. Producing gestures facilitates route learning.

    Directory of Open Access Journals (Sweden)

    Wing Chee So

    Full Text Available The present study investigates whether producing gestures would facilitate route learning in a navigation task and whether its facilitation effect is comparable to that of hand movements that leave physical visible traces. In two experiments, we focused on gestures produced without accompanying speech, i.e., co-thought gestures (e.g., an index finger traces the spatial sequence of a route in the air. Adult participants were asked to study routes shown in four diagrams, one at a time. Participants reproduced the routes (verbally in Experiment 1 and non-verbally in Experiment 2 without rehearsal or after rehearsal by mentally simulating the route, by drawing it, or by gesturing (either in the air or on paper. Participants who moved their hands (either in the form of gestures or drawing recalled better than those who mentally simulated the routes and those who did not rehearse, suggesting that hand movements produced during rehearsal facilitate route learning. Interestingly, participants who gestured the routes in the air or on paper recalled better than those who drew them on paper in both experiments, suggesting that the facilitation effect of co-thought gesture holds for both verbal and nonverbal recall modalities. It is possibly because, co-thought gesture, as a kind of representational action, consolidates spatial sequence better than drawing and thus exerting more powerful influence on spatial representation.

  17. Producing gestures facilitates route learning.

    Science.gov (United States)

    So, Wing Chee; Ching, Terence Han-Wei; Lim, Phoebe Elizabeth; Cheng, Xiaoqin; Ip, Kit Yee

    2014-01-01

    The present study investigates whether producing gestures would facilitate route learning in a navigation task and whether its facilitation effect is comparable to that of hand movements that leave physical visible traces. In two experiments, we focused on gestures produced without accompanying speech, i.e., co-thought gestures (e.g., an index finger traces the spatial sequence of a route in the air). Adult participants were asked to study routes shown in four diagrams, one at a time. Participants reproduced the routes (verbally in Experiment 1 and non-verbally in Experiment 2) without rehearsal or after rehearsal by mentally simulating the route, by drawing it, or by gesturing (either in the air or on paper). Participants who moved their hands (either in the form of gestures or drawing) recalled better than those who mentally simulated the routes and those who did not rehearse, suggesting that hand movements produced during rehearsal facilitate route learning. Interestingly, participants who gestured the routes in the air or on paper recalled better than those who drew them on paper in both experiments, suggesting that the facilitation effect of co-thought gesture holds for both verbal and nonverbal recall modalities. It is possibly because, co-thought gesture, as a kind of representational action, consolidates spatial sequence better than drawing and thus exerting more powerful influence on spatial representation. PMID:25426624

  18. Corpus Linguistics Facilitates English Teaching

    Institute of Scientific and Technical Information of China (English)

    朱思亲

    2014-01-01

    Corpus linguistics has been widely applied in English teaching. Corpus linguistics has changed the way to teach English. The essay discusses two approaches in English teaching based on corpus, corpus-driven approach and corpus-based approach. It finds out that both corpus-driven approach and corpus-based approach facilitate English teaching in their own ways.

  19. How Do the Size, Charge and Shape of Nanoparticles Affect Amyloid β Aggregation on Brain Lipid Bilayer?

    Science.gov (United States)

    Kim, Yuna; Park, Ji-Hyun; Lee, Hyojin; Nam, Jwa-Min

    2016-01-01

    Here, we studied the effect of the size, shape, and surface charge of Au nanoparticles (AuNPs) on amyloid beta (Aβ) aggregation on a total brain lipid-based supported lipid bilayer (brain SLB), a fluid platform that facilitates Aβ-AuNP aggregation process. We found that larger AuNPs induce large and amorphous aggregates on the brain SLB, whereas smaller AuNPs induce protofibrillar Aβ structures. Positively charged AuNPs were more strongly attracted to Aβ than negatively charged AuNPs, and the stronger interactions between AuNPs and Aβ resulted in fewer β-sheets and more random coil structures. We also compared spherical AuNPs, gold nanorods (AuNRs), and gold nanocubes (AuNCs) to study the effect of nanoparticle shape on Aβ aggregation on the brain SLB. Aβ was preferentially bound to the long axis of AuNRs and fewer fibrils were formed whereas all the facets of AuNCs interacted with Aβ to produce the fibril networks. Finally, it was revealed that different nanostructures induce different cytotoxicity on neuroblastoma cells, and, overall, smaller Aβ aggregates induce higher cytotoxicity. The results offer insight into the roles of NPs and brain SLB in Aβ aggregation on the cell membrane and can facilitate the understanding of Aβ-nanostructure co-aggregation mechanism and tuning Aβ aggregate structures.

  20. Network Provisioning Using Multimedia Aggregates

    Directory of Open Access Journals (Sweden)

    Joan Vila-Carbó

    2008-01-01

    Full Text Available Multimedia traffic makes network provisioning a key issue. Optimal provisioning of network resources is crucial for reducing the service cost of multimedia transmission. Multimedia traffic requires not only provisioning bandwidth and buffer resources in the network but also guaranteeing a given maximum end-to-end delay. In this paper we present methods and tools for the optimal dimensioning of networks based on multimedia aggregates. The proposed method minimises the network resources reservations of traffic aggregates providing a bounded delay. The paper also introduces several methods to generate multimedia traffic aggregation using real video traces. The method is evaluated using a network topology based on the European GÉANT network. The results of these simulations allow us to discover the relationship between a required delay and the necessary bandwidth reservation (or the achievable utilisation limit. An interesting conclusion of these scenarios is that, following several recommendations, the network utilisation can reach values of around 80% or higher.

  1. Changes in the phenology of the ground beetle Pterostichus madidus

    Institute of Scientific and Technical Information of China (English)

    Gabor Pozsgai; Nick A. Littlewood

    2011-01-01

    A growing body ofevidence shows that climate change can alter the phenology of plants and animals.In this study long-term data from the UK Environmental Change Network (ECN) were analyzed to investigate whether there has been a change in the phenology of the ground beetle Pterostichus madidus (Fabricius,1775).Pitfall trap data were available from 12 ECN sites across the United Kingdom,most of which have been in operation for more than 15 years.Weather and vegetation datasets were also utilized.Pitfall trap lines were categorized to eight vegetation types.Trend analysis over time was carried out first using all the available dates of capture events,then the datasets grouped by vegetation type and site.Shifts in high-activity periods were also analyzed.P.madidus appearance dates advanced significantly at seven sites and in five vegetation types.Peak activity advanced at two sites.At one site the timing of activity became significantly later.The last day of activity did not change significantly,supporting the theory that the cessation of the activity period is more likely to be controlled by photoperiod than temperature.The relationships between phenological variables and climatic factors were also investigated.However,no significant correlations were detected.These results demonstrate that between 1992 and 2008,phenology ofP madidus at seven sites from the eight analyzed has changed.Global warming may be driving these changes and future work will investigate underlying processes.

  2. The Beetle Reference Manual chip version 1.2

    CERN Document Server

    Baumeister, D; Schmelling, M

    2006-01-01

    This paper details the electrical specifications, operating conditions and port definitions of the readout chip Beetle 1.2. The chip is developed for the LHCb experiment and fulfils the requirements of the silicon vertex detector (VELO, VETO), the silicon tracker and the RICH detector in case of multi-anode photomultiplier readout. It integrates 128 channels with low-noise charge-sensitive preamplifiers and shapers. The pulse shape can be chosen such that it complies with LHCb specifications: a peaking time of 25 ns with a remainder of the peak voltage after 25 ns of less than 30%. A comparator per channel with configurable polarity provides a binary signal. Four adjacent comparator channels are being ORed and brought off chip via LVDS ports. Either the shaper or comparator output is sampled with the LHC-bunch-crossing frequency of 40 MHz into an analog pipeline. This ring buffer has a programmable latency of max. 160 sampling intervals and an integrated derandomising buffer of 16 stages. For analog readout d...

  3. Aerodynamics of a beetle in take-off flights

    Science.gov (United States)

    Lee, Boogeon; Park, Hyungmin; Kim, Sun-Tae

    2015-11-01

    In the present study, we investigate the aerodynamics of a beetle in its take-off flights based on the three-dimensional kinematics of inner (hindwing) and outer (elytron) wings, and body postures, which are measured with three high-speed cameras at 2000 fps. To track the highly deformable wing motions, we distribute 21 morphological markers and use the modified direct linear transform algorithm for the reconstruction of measured wing motions. To realize different take-off conditions, we consider two types of take-off flights; that is, one is the take-off from a flat ground and the other is from a vertical rod mimicking a branch of a tree. It is first found that the elytron which is flapped passively due to the motion of hindwing also has non-negligible wing-kinematic parameters. With the ground, the flapping amplitude of elytron is reduced and the hindwing changes its flapping angular velocity during up and downstrokes. On the other hand, the angle of attack on the elytron and hindwing increases and decreases, respectively, due to the ground. These changes in the wing motion are critically related to the aerodynamic force generation, which will be discussed in detail. Supported by the grant to Bio-Mimetic Robot Research Center funded by Defense Acquisition Program Administration (UD130070ID).

  4. Modeling mountain pine beetle habitat suitability within Sequoia National Park

    Science.gov (United States)

    Nguyen, Andrew

    Understanding significant changes in climate and their effects on timber resources can help forest managers make better decisions regarding the preservation of natural resources and land management. These changes may to alter natural ecosystems dependent on historical and current climate conditions. Increasing mountain pine beetle (MBP) outbreaks within the southern Sierra Nevada are the result of these alterations. This study better understands MPB behavior within Sequoia National Park (SNP) and model its current and future habitat distribution. Variables contributing to MPB spread are vegetation stress, soil moisture, temperature, precipitation, disturbance, and presence of Ponderosa (Pinus ponderosa) and Lodgepole (Pinus contorta) pine trees. These variables were obtained using various modeled, insitu, and remotely sensed sources. The generalized additive model (GAM) was used to calculate the statistical significance of each variable contributing to MPB spread and also created maps identifying habitat suitability. Results indicate vegetation stress and forest disturbance to be variables most indicative of MPB spread. Additionally, the model was able to detect habitat suitability of MPB with a 45% accuracy concluding that a geospatial driven modeling approach can be used to delineate potential MPB spread within SNP.

  5. Phenotypes of Non-Attached Pseudomonas aeruginosa Aggregates Resemble Surface Attached Biofilm

    DEFF Research Database (Denmark)

    Alhede, Morten; Kragh, Kasper Nørskov; Qvortrup, Klaus;

    2011-01-01

    physiological states of the aggregates and particular matrix components. Bacterial surface-attachment and subsequent biofilm formation are considered hallmarks of the capacity of microbes to cause persistent infections. We have observed non-attached aggregates in the lungs of cystic fibrosis patients; otitis......For a chronic infection to be established, bacteria must be able to cope with hostile conditions such as low iron levels, oxidative stress, and clearance by the host defense, as well as antibiotic treatment. It is generally accepted that biofilm formation facilitates tolerance to these adverse...... age, both aggregates and flow-cell biofilm had the same slow growth rate as a stationary phase shaking cultures. Internal structures of the aggregates matrix components and their capacity to survive otherwise lethal treatments with antibiotics (referred to as tolerance) and resistance to phagocytes...

  6. Restudies on Body Surface of Dung Beetle and Application of Its Bionics Flexible Technique

    Institute of Scientific and Technical Information of China (English)

    Jiurong Sun; Jianqiao Li; Hong Cheng; Zhendong Dai; Luquan Ren

    2004-01-01

    A scanning electron microscope was used to observe the structures of the setae on the surface of a dung beetle Copris ochus, Motschulsky. There are lots of setae on the body surface, especially on the ventral part surface and lateral to the legs which are different in size, arrangement and shape. These setae have different lengths and many thorns on the whole seta. The top ends of these setae stand up without furcations which direct uprightly towards the surface of the touched soil. By the method of removing these setae, getting the insect weight before and after digging into the dung we affirm farther that the setae on the beetle body surface form the anti-stick and non-adherent gentle interface. The soil machines and components made by imitating the gentle body surface of beetles have favorable non-adherent results.

  7. Phylogeny of diving beetles reveals a coevolutionary arms race between the sexes.

    Directory of Open Access Journals (Sweden)

    Johannes Bergsten

    Full Text Available BACKGROUND: Darwin illustrated his sexual selection theory with male and female morphology of diving beetles, but maintained a cooperative view of their interaction. Present theory suggests that instead sexual conflict should be a widespread evolutionary force driving both intersexual coevolutionary arms races and speciation. METHODOLOGY/PRINCIPAL FINDINGS: We combined Bayesian phylogenetics, complete taxon sampling and a multi-gene approach to test the arms race scenario on a robust diving beetle phylogeny. As predicted, suction cups in males and modified dorsal surfaces in females showed a pronounced coevolutionary pattern. The female dorsal modifications impair the attachment ability of male suction cups, but each antagonistic novelty in females corresponds to counter-differentiation of suction cups in males. CONCLUSIONS: A recently diverged sibling species pair in Japan is possibly one consequence of this arms race and we suggest that future studies on hypoxia might reveal the key to the extraordinary selection for female counter-adaptations in diving beetles.

  8. A System for Harvesting Eggs from the Pink-Spotted Lady Beetle

    Directory of Open Access Journals (Sweden)

    Margaret L. Allen

    2012-01-01

    Full Text Available We describe a system for harvesting eggs from a predatory insect, the pink-spotted lady beetle, Coleomegilla maculata De Geer (Coleoptera: Coccinellidae. Adult beetles placed in square, transparent containers that included oviposition substrates hanging from the top of the cage deposited eggs on the materials provided. We harvested eggs from these substrates in quantities sufficient for either destructive sampling or synchronous development of larvae. We evaluated effects of crowding inside cages; effects of a chemical attractant on oviposition behavior; egg cannibalism. Females preferred a textured surface rather than a smooth, waxy one for laying eggs. Crowding inhibited oviposition of beetles. Presence of a chemical attractant (methyl salicylate did not significantly improve oviposition. This paper describes an inexpensive system for harvesting eggs from C. maculata. Refinement of this system should improve oviposition and reduce cannibalism.

  9. BIOACTIVITY OF 1,8-CINEOLE AGAINST RED FLOUR BEETLE TRIBOLIUM CASTANEUM (HERBST

    Directory of Open Access Journals (Sweden)

    Anita Liška

    2011-06-01

    Full Text Available Red flour beetle Tribolium castaneum (Herbst is a major pest of stored products. The aim of this study was to assess the potential fumigant effects of 1,8-cineole, essential oil component, on the T. castaneum pupae. The compound was tested in 6 doses; in two treatments (fumigation without grain and with wheat grain, exposed for 48 h, in 4 repetitions, for each gender. The compound 1,8-cineole had lethal effect on the treated pupae at both genders and in the both treatments. Total proportion of the normally developed beetles was decreased. In addition, 1,8-cineole had also a growth regulator effect, producing adultoids and deformed units, with males more susceptible. In the treatment with the grain there were significant lower dead pupae, normally developed live male beetles and also deformed female units in the stage 2. In general, compound 1,8-cineole has multiple effect against T. castaneum in pupal stage.

  10. Use of habitat resources by scarab dung beetles in an Savanna

    DEFF Research Database (Denmark)

    Carpaneto, Giuseppe Maria; Mazziotta, Adriano; Ieradi, Michele

    2010-01-01

    In the Queen Elizabeth National Park, Uganda, we compared the scarab beetle assemblages in the dung of three wild ungulates (African buffalo, a ruminant foregut fermenter; hippopotamus, nonruminant foregut fermenter; and warthog, nonruminant hindgut fermenter). Dung was collected from two sandy......-clay soils with different percentage of coarse sand. We aimed at investigating habitat resource selection by dung beetle species within a savanna natural contest with abundant and diverse food availability. Analyses were performed to detect differences for dung beetle assemblages in abundance, diversity......, functional groups. Species richness in the three dung types and in the two soil types was similar. However, warthog dung and sandy-rich soil appeared the preferred habitat resources, in terms of abundance and biomass, while hippopotamus dung hosted the lowest values for these parameters. The analysis of...

  11. Development of red-shifted mutants derived from luciferase of Brazilian click beetle Pyrearinus termitilluminans

    Science.gov (United States)

    Nishiguchi, Tomoki; Yamada, Toshimichi; Nasu, Yusuke; Ito, Mashiho; Yoshimura, Hideaki; Ozawa, Takeaki

    2015-10-01

    Luciferase, a bioluminescent protein, has been used as an analytical tool to visualize intracellular phenomena. Luciferase with red light emission is particularly useful for bioluminescence imaging because of its high transmittance in mammalian tissues. However, the luminescence intensity of existing luciferases with their emission over 600 nm is insufficient for imaging studies because of their weak intensities. We developed mutants of Emerald luciferase (Eluc) from Brazilian click beetle (Pyrearinus termitilluminans), which emits the strongest bioluminescence among beetle luciferases. We successively introduced four amino acid mutations into the luciferase based on a predicted structure of Eluc using homology modeling. Results showed that quadruple mutations R214K/H241K/S246H/H347A into the beetle luciferase emit luminescence with emission maximum at 626 nm, 88-nm red-shift from the wild-type luciferase. This mutant luciferase is anticipated for application in in vivo multicolor imaging in living samples.

  12. Nutrient richness of wood mould in tree hollows with the Scarabaeid beetle Osmoderma eremita

    Directory of Open Access Journals (Sweden)

    Jönsson, N.

    2004-11-01

    Full Text Available Trunk hollows with wood mould habour a rich invertebrate fauna with many threatened species, and it has been suggested that the beetle Osmoderma eremita (Coleoptera, Scarabaeoidea is a keystone species in this community. We estimated the amount of nitrogen and phosphorus in wood mould and compared the coarse fraction which constitutes frass of O. eremita with the finer fraction of wood mould, and found that the nutrient richness was higher in frass. O. eremita larvae have a fermentation chamber that harbours nitrogen fixing bacteria. As the levels of absorbable nitrogen are a limiting factor in insect growth, an increase in nutrient richness is one of several possible explanations why the species richness of saproxylic beetles is higher in hollow oaks where O. eremita is present in relation to similar trees where the beetle is absent

  13. Acetylcholinesterase inhibition and altered locomotor behavior in the carabid beetle pterostichus

    DEFF Research Database (Denmark)

    Jensen, Charlotte S.; Krause-Jensen, Lone; Baatrup, Erik

    1997-01-01

    The establishment of cause–effect relationships is fundamental for the interpretation and the predictive value of biomarker responses measured at all levels of biological complexity. In the present study, the biochemical exposure biomarker acetylcholinesterase (AChE) inhibition was related to...... locomotor behavior, representing a general effect biomarker at the organismal level. Both sexes of the carabid beetle Pterostichus cupreus were intoxicated with three doses of the organophosphorous insecticide dimethoate. Five elements of their locomotor behavior were measured for 4 h employing computer......-aided video tracking, whereupon the whole body AChE activity was measured in the individual beetle. AChE inhibition was strongly correlated with dimethoate dose in both sexes. Alterations in the locomotor behavior were directly correlated with AChE inhibition in male beetles, which responded by reducing the...

  14. Molecular cloning, expression, purification and characterization of a novel cellulase gene (Bh-EGaseI) in the beetle Batocera horsfieldi.

    Science.gov (United States)

    Mei, Hui-Zhen; Xia, Ding-Guo; Zhao, Qiao-Ling; Zhang, Guo-Zheng; Qiu, Zhi-Yong; Qian, Ping; Lu, Cheng

    2016-01-15

    Wood-feeding insects depend heavily on the secretion of a combination of cellulases, mainly endoglucanases and other glucanases such as exoglucanases and xylanases, to achieve efficient digestion of the cellulose of cellulosic materials. In this paper, we report a novel cellulose Bh-EGaseI belonging to the glycoside hydrolase family 45(gh45-1) obtained from the beetle Batocera horsfieldi. The Bh-EGaseI gene spans 714 bp and consists of three exons coding 237 amino acid residues. The cDNA encoding Bh-EGaseI was expressed as 25 KDa in baculovirus-infected Bombyx mori larvae. The expression products of Bh-EGaseI from larval hemolymph showed a specific enzymatic activity of approximately 1030.87 IU per mg. The enzyme was active over a wide range of pH and temperatures; optimal activity was observed at 40 °C and pH 4.0. The effects of ions on Bh-EGaseI activity were also studied, and results indicated that activity decreased to different extents upon addition of ions. Investigations on Bh-EGaseI facilitate their potential application in the production of bioenergy and biomaterials from cellulosic biomass in the future. PMID:26410410

  15. [AGGREGATION OF METABOLICALLY DEPLETED HUMAN ERYTHROCYTES].

    Science.gov (United States)

    Sheremet'ev, Yu A; Popovicheva, A N; Rogozin, M M; Levin, G Ya

    2016-01-01

    An aggregation of erythrocytes in autologous plasma after blood storage for 14 days at 4 °C was studied using photometry and light microscopy. The decrease of ATP content, the formation of echinocytes and spheroechinocytes, the decrease of rouleaux form of erythrocyte aggregation were observed during the storage. On the other hand the aggregates of echinocytes were formed in the stored blood. The addition of plasma from the fresh blood didn't restore the normal discocytic shape and aggregation of erythrocytes in the stored blood. The possible mechanisms of erythrocytes and echinocytes aggregation are discussed. PMID:27220249

  16. [Lysophosphatidic acid and human erythrocyte aggregation].

    Science.gov (United States)

    Sheremet'ev, Iu A; Popovicheva, A N; Levin, G Ia

    2014-01-01

    The effects of lysophosphatidic acid on the morphology and aggregation of human erythrocytes has been studied. Morphology of erythrocytes and their aggregates were studied by light microscopy. It has been shown that lysophosphatidic acid changes the shape of red blood cells: diskocyte become echinocytes. Aggregation of red blood cells (rouleaux) was significantly reduced in autoplasma. At the same time there is a strong aggregation of echinocytes. This was accompanied by the formation of microvesicles. Adding normal plasma to echinocytes restores shape and aggregation of red blood cells consisting of "rouleaux". A possible mechanism of action of lysophosphatidic acid on erythrocytes is discussed. PMID:25509147

  17. Carbon stocks of trees killed by bark beetles and wildfire in the western United States

    International Nuclear Information System (INIS)

    Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined existing spatial data sets of forest biomass, burn severity, and beetle-caused tree mortality to estimate the amount of aboveground and belowground carbon in killed trees across the region. We found that during 1984–2010, fires killed trees that contained 5–11 Tg C year−1 and during 1997–2010, beetles killed trees that contained 2–24 Tg C year−1, with more trees killed since 2000 than in earlier periods. Over their periods of record, amounts of carbon in trees killed by fires and by beetle outbreaks were similar, and together these disturbances killed trees representing 9% of the total tree carbon in western forests, a similar amount to harvesting. Fires killed more trees in lower-elevation forest types such as Douglas-fir than higher-elevation forest types, whereas bark beetle outbreaks also killed trees in higher-elevation forest types such as lodgepole pine and Engelmann spruce. Over 15% of the carbon in lodgepole pine and spruce/fir forest types was in trees killed by beetle outbreaks; other forest types had 5–10% of the carbon in killed trees. Our results document the importance of these natural disturbances in the carbon budget of the western United States. (letter)

  18. Flight behavior of the rhinoceros beetle Trypoxylus dichotomus during electrical nerve stimulation

    International Nuclear Information System (INIS)

    Neuronal stimulation is an intricate part of understanding insect flight behavior and control insect itself. In this study, we investigated the effects of electrical pulses applied to the brain and basalar muscle of the rhinoceros beetle (Trypoxylus dichotomus). To understand specific neuronal stimulation mechanisms, responses and flight behavior of the beetle, four electrodes were implanted into the two optic lobes, the brain's central complex and the ventral nerve cord in the posterior pronotum. We demonstrated flight initiation, turning and cessation by stimulating the brain. The change undergone by the wing flapping in response to the electrical signal was analyzed from a sequence of images captured by a high-speed camera. Here, we provide evidence to distinguish the important differences between neuronal and muscular flight stimulations in beetles. We found that in the neural potential stimulation, both the hind wing and the elytron were suppressed. Interestingly, the beetle stopped flying whenever a stimulus potential was applied between the pronotum and one side of the optic lobe, or between the ventral nerve cord in the posterior pronotum and the central complex. In-depth experimentation demonstrated the effective of neural stimulation over muscle stimulation for flight control. During electrical stimulation of the optic lobes, the beetle performed unstable flight, resulting in alternating left and right turns. By applying the electrical signal into both the optic lobes and the central complex of the brain, we could precisely control the direction of the beetle flight. This work provides an insight into insect flight behavior for future development of insect-micro air vehicle. (paper)

  19. Brood ball-mediated transmission of microbiome members in the dung beetle, Onthophagus taurus (Coleoptera: Scarabaeidae.

    Directory of Open Access Journals (Sweden)

    Anne M Estes

    Full Text Available Insects feeding on plant sap, blood, and other nutritionally incomplete diets are typically associated with mutualistic bacteria that supplement missing nutrients. Herbivorous mammal dung contains more than 86% cellulose and lacks amino acids essential for insect development and reproduction. Yet one of the most ecologically necessary and evolutionarily successful groups of beetles, the dung beetles (Scarabaeinae feeds primarily, or exclusively, on dung. These associations suggest that dung beetles may benefit from mutualistic bacteria that provide nutrients missing from dung. The nesting behaviors of the female parent and the feeding behaviors of the larvae suggest that a microbiome could be vertically transmitted from the parental female to her offspring through the brood ball. Using sterile rearing and a combination of molecular and culture-based techniques, we examine transmission of the microbiome in the bull-headed dung beetle, Onthophagus taurus. Beetles were reared on autoclaved dung and the microbiome was characterized across development. A ~1425 bp region of the 16S rRNA identified Pseudomonadaceae, Enterobacteriaceae, and Comamonadaceae as the most common bacterial families across all life stages and populations, including cultured isolates from the 3(rd instar digestive system. Finer level phylotyping analyses based on lepA and gyrB amplicons of cultured isolates placed the isolates closest to Enterobacter cloacae, Providencia stuartii, Pusillimonas sp., Pedobacter heparinus, and Lysinibacillus sphaericus. Scanning electron micrographs of brood balls constructed from sterile dung reveals secretions and microbes only in the chamber the female prepares for the egg. The use of autoclaved dung for rearing, the presence of microbes in the brood ball and offspring, and identical 16S rRNA sequences in both parent and offspring suggests that the O. taurus female parent transmits specific microbiome members to her offspring through the brood

  20. Dung beetle assemblages (Coleoptera, Scarabaeinae in Atlantic forest fragments in southern Brazil

    Directory of Open Access Journals (Sweden)

    Renata C. Campos

    2013-03-01

    Full Text Available Dung beetle assemblages (Coleoptera, Scarabaeinae in Atlantic forest fragments in southern Brazil. The beetles of the subfamily Scarabaeinae are important organisms that participate in the cycle of decomposition, especially in tropical ecosystems. Most species feed on feces (dung or carcasses (carrion and are associated with animals that produce their food resources. Dung beetles are divided into three functional groups: rollers, tunnelers and dwellers. This present work aims to study the diversity of dung beetle communities inhabiting fragments of the Atlantic Forest, with the purpose of describing the ecology of the species in southern Brazil. This study was conducted in the region of Campos Novos, in Santa Catarina, where twenty sites of Atlantic forest fragments were sampled. Samplings of dung beetles were conducted using 200 pitfall traps, of which 100 were baited with human feces and another 100 with carrion. Size and environmental complexity were also measured for each forest fragment. A total of 1,502 dung beetles, belonging to six tribes, 12 genera and 33 species, were collected. Results of the Levin's index of niche breadth indicated that 11 species were categorized as being coprophagous, ten as generalists, and two as necrophagous. Most species are tunnelers (19, nine of rollers and four of dwellers. The great diversity of Scarabaeinae in the region of Campos Novos, including several rare species, adds important data to the Scarabaeinae fauna in the central-western region of Santa Catarina. It may also help choosing priority areas for conservation in the region, where human impact, with large areas of monoculture, increasingly threatens the fragments of Mixed Ombrophilous Forest.

  1. Diversity and abundance of dung beetles (Coleoptera: Scaraebidae) at several different ecosystem functions in Peninsular Malaysia

    Science.gov (United States)

    Din, Abdullah Muhaimin Mohammad; Yaakop, Salmah; Hazmi, Izfa Riza

    2015-09-01

    Dung beetles has known for its bioindicator characteristic. Sensitive towards forest disturbance, dung beetles population and diversity will be less in disturbed and modified area. The objective of this study is to evaluate the diversity and distribution of dung beetles in different type of ecosystems in Peninsular Malaysia. Fifteen baited pitfall traps aligned in three transects were used in this study. Samples were collected after 24 h and repeated three time collections and identified afterwards. Two ecosystem types were selected, which are forested and agricultural ecosystem (livestock and plantation). A total of 4249 individuals, 47 species, in 11 genera was successfully collected from all localities. The H' index for Fraser Hill, Langkawi, Bangi Reserve Forest, Selangor (HSB), Sungkai Reserve Forest, Perak (SRF), Chini Lake, Bera Lake, chicken farm, goat farm, Longan plantation, and palm oil plantation were 1.58, 1.74, 2.17, 2.63, 1.80, 1.52, 1.63, 0.46, 0.00 and 1.98 respectively.Forest ecosystem, SRF shows the highest abundance (1486 individuals) and diversity, while for agricultural ecosystem,palm oil plantation shows the highest with 273 individuals and 16 species. Based onDetrended Correspondence Analysis (DCA) shows two groups that separate forest ecosystem with the agricultural ecosystem, with palm oil is the nearest to the forest. Palm oil ecosystem can sustain a dung beetles population due to the area can provide the requirements for the dung beetles to survive, such as food which comes from local domestic cows, shade from sunlight provide by the palm oil trees, and ground cover from small plants and shrubs.Even though modified ecosystem should have lower diversity of dung beetles, but some factors must be measured as well in order to have a better point of view.

  2. A comparison of trap type and height for capturing cerambycid beetles (Coleoptera).

    Science.gov (United States)

    Graham, Elizabeth E; Poland, Therese M; McCullough, Deborah G; Millar, Jocelyn G

    2012-06-01

    Wood-boring beetles in the family Cerambycidae (Coleoptera) play important roles in many forest ecosystems. However, increasing numbers of invasive cerambycid species are transported to new countries by global commerce and threaten forest health in the United States and worldwide. Our goal was to identify effective detection tools for a broad array of cerambycid species by testing some known cerambycid attractants and a pheromone in different trap designs placed across a range of habitats. We compared numbers and species richness of cerambycid beetles captured with cross-vane panel traps and 12-unit Lindgren multiple-funnel traps, placed either at ground level (1.5 m high) or canopy level (approximately 3-10 m high), at eight sites classified as either residential, industrial, deciduous forest, or conifer forest. We captured 3,723 beetles representing 72 cerambycid species from 10 June to 15 July 2010. Species richness was highest for the subfamilies Cerambycinae and Lamiinae, which accounted for 33 and 46% of all species captured, respectively. Overall, the cross-vane panel traps captured approximately 1.5 times more beetles than funnel traps. Twenty-one species were captured exclusively in traps at one height, either in the canopy or at ground level. More species were captured in hardwood sites (59 species) where a greater diversity of host material was available than in conifer (34 species), residential (41 species), or industrial (49) sites. Low numbers of beetles (n < 5) were recorded for 28 of the beetle species. The number of species captured per week ranged from 49 species on 21 June to 37 species on 12 July. Cross-vane panel traps installed across a vertical gradient should maximize the number of cerambycid species captured. PMID:22812119

  3. Carbon stocks of trees killed by bark beetles and wildfire in the western United States

    Science.gov (United States)

    Hicke, Jeffrey A.; Meddens, Arjan J.H.; Allen, Craig D.; Kolden, Crystal A.

    2013-01-01

    Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined existing spatial data sets of forest biomass, burn severity, and beetle-caused tree mortality to estimate the amount of aboveground and belowground carbon in killed trees across the region. We found that during 1984-2010, fires killed trees that contained 5-11 Tg C year-1 and during 1997-2010, beetles killed trees that contained 2-24 Tg C year-1, with more trees killed since 2000 than in earlier periods. Over their periods of record, amounts of carbon in trees killed by fires and by beetle outbreaks were similar, and together these disturbances killed trees representing 9% of the total tree carbon in western forests, a similar amount to harvesting. Fires killed more trees in lower-elevation forest types such as Douglas-fir than higher-elevation forest types, whereas bark beetle outbreaks also killed trees in higher-elevation forest types such as lodgepole pine and Engelmann spruce. Over 15% of the carbon in lodgepole pine and spruce/fir forest types was in trees killed by beetle outbreaks; other forest types had 5-10% of the carbon in killed trees. Our results document the importance of these natural disturbances in the carbon budget of the western United States.

  4. Aggregation of Diesel Contaminated Soil for Bioremediation

    Institute of Scientific and Technical Information of China (English)

    Yu Ying; Shi Xiu-hong; Li Song; Xu Jing-gang

    2014-01-01

    Diesel contaminated soil (DCS) contained a large amount of the hydrocarbons and salt which was dominated by soluble sodium chloride. Aggregation process which made the desired aggregate size distribution could speed up the degradation rate of the hydrocarbons since the aggregated DCS had better physical characteristics than the non-aggregated material. Artificial aggregation increased pores >30 µm by approximately 5% and reduced pores <1 µm by 5%, but did not change the percentage of the pores between 1 and 30 µm. The saturated hydraulic conductivity of non-aggregated DCS was 5×10-6 m• s-l, but it increased to 1×10-5 m• s-l after aggregation. The compression index of the non-aggregated DCS was 0.0186; however, the artificial aggregates with and without lime were 0.031 and 0.028, respectively. DCS could be piled 0.2 m deep without artificial aggregation; however, it could be applied 0.28 m deep when artificial aggregates were formed without limiting O2 transport.

  5. [Behavioral mechanisms of spatial competition between red wood ants (Formica aquilonia) and ground beetles (Carabidae)].

    Science.gov (United States)

    Dorosheva, E A; Reznikova, Zh I

    2006-01-01

    Behavioral aspects of spatial competition between red wood ants (Formica aquilonia) and six mass species of Carabidae were studied in field and laboratory experiments. We showed that red wood ants essentially influence spatial distribution of ground beetles on their common territories. Transplantation experiments suggest that in newly established ants' settlements stronger forms of interrelations arise than in old stable colony. To examine the ability of beetles to avoid collisions with ants we used two experimental techniques. In laboratory, we tested carabids ability to avoid a clash in a Y-shaped labyrinth containing an active tethered ant in one section. In field experiments we compared quantitative characteristics of movements (such as crookedness of individual trajectories, speed of movement, the time spent on stops) for beetles placed close to ants foraging routes and on ant-free plots. All beetles studied displayed a clear tendency to learn, that is, to modity their behavior in order to avoid collisions with ants. Species that exhibited best parameters of learning were closer to ants by their size and characteristic movement, namely, Pterostichus oblogopunctatus and P. magus. Beetles' stereotyped behavioral tactics can be considered universal for avoiding collisions with any subject (for instance, with an ant) of a certain size and speed of movements. A set of tactics in the labyrinth included: (1) attempts to round the ant; (2) turns away after touching the ant with antennae; (3) turns away without a contact; (4) avoidances of a dangerous section; (5) stops near the ant with the antennae hidden. Comparing pairwise difference between four species shows that beetles use species-specific preference for definite combinations of tactics. Effective learning allows carabids to penetrate into ant foraging territory and partly avoide interference competition. It seems that red wood ants are not inclined to learn to avoid collisions with competing carabid species

  6. Beetle species diversity in the Lesser Antilles islands: How many species are really there?

    OpenAIRE

    Peck, Stewart B.

    2009-01-01

    Recent extensive and intensive field work by the team of M. A. Ivie on the Lesser Antillean island of Montserrat suggests that a mean of 827 beetle species may be expected on that island. This datum makes possible the generation of hypotheses of the probable beetle species diversity on other islands of the Lesser Antilles as a function of the areas of the islands. Figures are given for the presently known, estimated total, and estimated number of unknown species for each principal island. Thi...

  7. Susceptibility of the small hive beetle, Aethina tumida (Coleoptera: Nitidulidae), to insecticides and insect growth regulators

    OpenAIRE

    Kanga, Lambert; Somorin, Abisoye

    2011-01-01

    International audience The small hive beetle, Aethina tumida Murray, has become an important pest of the honeybee, Apis mellifera L., in the USA. In this study, we assessed the susceptibility of this pest to 14 selected insecticides and four insect growth regulators (IGRs). The results indicated that the small hive beetle (SHB) was selectively susceptible to several classes of insecticides. The lethal concentration for 50% mortality (LC50) to adult SHBs was 0.53, 0.53, and 0.54 μg/vial for...

  8. The small hive beetle Aethina tumida: A review of its biology and control measures

    OpenAIRE

    Andrew G. S. CUTHBERTSON et al

    2013-01-01

    The small hive beetle Aethina tumida is an endemic parasitic pest and scavenger of colonies of social bees indigenous to sub-Saharan Africa. In this region this species rarely inflicts severe damage on strong colonies since the bees have develo­­ped strategies to combat them. However, A. tumida has since ‘escaped’ from its native home and has recently invaded areas such as North America and Australia where its economic impact on the apiculture industry has been significant. Small hive beetle,...

  9. Dung beetles use their dung ball as a mobile thermal refuge

    OpenAIRE

    Smolka, Jochen; Baird, Emily; Byrne, Marcus; el Jundi, Basil; Warrant, Eric; Dacke, Marie

    2012-01-01

    At midday, surface temperatures in the desert often exceed 60°C. To be active at this time, animals need extraordinary behavioural or physiological adaptations. Desert ants, for instance, spend up to 75% of their foraging time cooling down on elevated thermal refuges such as grass stalks [1]. Ball-rolling dung beetles work under similar thermal conditions in South African savannahs. After landing at a fresh dung pile, a beetle quickly forms a dung ball and rolls it away in a straight line, he...

  10. Bouncing Behavior of Microscopic Dust Aggregates

    CERN Document Server

    Seizinger, Alexander

    2013-01-01

    Context: Bouncing collisions of dust aggregates within the protoplanetary may have a significant impact on the growth process of planetesimals. Yet, the conditions that result in bouncing are not very well understood. Existing simulations studying the bouncing behavior used aggregates with an artificial, very regular internal structure. Aims: Here, we study the bouncing behavior of sub-mm dust aggregates that are constructed applying different sample preparation methods. We analyze how the internal structure of the aggregate alters the collisional outcome and determine the influence of aggregate size, porosity, collision velocity, and impact parameter. Methods: We use molecular dynamics simulations where the individual aggregates are treated as spheres that are made up of several hundred thousand individual monomers. The simulations are run on GPUs. Results: Statistical bulk properties and thus bouncing behavior of sub-mm dust aggregates depend heavily on the preparation method. In particular, there is no uni...

  11. An exact approach for aggregated formulations

    DEFF Research Database (Denmark)

    Gamst, Mette; Spoorendonk, Simon

    Aggregating formulations is a powerful approach for transforming problems into taking more tractable forms. Aggregated formulations can, though, have drawbacks: some information may get lost in the aggregation and { put in a branch-and-bound context { branching may become very di_cult and even...... mathematical formulation and the aggregated formulation. The method allows usage of relaxed aggregated formulations and enables branching on both aggregated and disaggregated variables. Also, the method guarantees an LP bound at least as good as those for the disaggregated and aggregated formulations. The...... paper includes general considerations on types of problems for which the method is of particular interest. Furthermore, we prove the correctness of the procedure and consider how to include extensions such as cutting planes and advanced branching strategies....

  12. Microwave extinction characteristics of nanoparticle aggregates

    Science.gov (United States)

    Wu, Y. P.; Cheng, J. X.; Liu, X. X.; Wang, H. X.; Zhao, F. T.; Wen, W. W.

    2016-07-01

    Structure of nanoparticle aggregates plays an important role in microwave extinction capacity. The diffusion-limited aggregation model (DLA) for fractal growth is utilized to explore the possible structures of nanoparticle aggregates by computer simulation. Based on the discrete dipole approximation (DDA) method, the microwave extinction performance by different nano-carborundum aggregates is numerically analyzed. The effects of the particle quantity, original diameter, fractal structure, as well as orientation on microwave extinction are investigated, and also the extinction characteristics of aggregates are compared with the spherical nanoparticle in the same volume. Numerical results give out that proper aggregation of nanoparticle is beneficial to microwave extinction capacity, and the microwave extinction cross section by aggregated granules is better than that of the spherical solid one in the same volume.

  13. Effects of vegetation restoration on the aggregate stability and distribution of aggregate-associated organic carbon in a typical karst gorge region

    Directory of Open Access Journals (Sweden)

    F. K. Tang

    2015-08-01

    Full Text Available Changes in soil utilization significantly affect aggregate stability and aggregate-associated soil organic carbon (SOC. A field investigation and indoor analysis were conducted in order to study the soil aggregate stability and organic carbon distribution in the water-stable aggregates (WSA of the bare land (BL, grassland (GL, shrubland (SL, and woodland (WL in a typical karst gorge region. The results indicated that the BL, GL, SL, and WL were dominated by particles with sizes > 5 mm under dry sieving treatment, and that the soil aggregate contents of various sizes decreased as the particle size decreased. In addition, the BL, GL, SL, and WL were predominantly comprised of WSA D of the dry aggregates and water-stable aggregates in the different types of land were ranked, in descending order, as WL > GL > SL > BL. The contents of WSA > 0.25 mm, MWD and GMD increased significantly, in that order, and the percentage of aggregate destruction (PAD and fractal dimensions decreased significantly as the soil aggregate stability improved. The results of this study indicated that, as the SOC contents increased after vegetation restoration, the average SOC content of WL was 2.35, 1.37, and 1.26 times greater than that in the BL, GL, and SL, respectively. The total SOC and SOC associated in WSA of various sizes were the highest at a soil depth of 0–20 cm. In addition, the SOC contents of the WSA increased as the soil aggregate sizes decreased. The SOC contents of the WSA < 0.25 mm were highest except in the bare land, and the SOC contents of the aggregates < 0.25 mm, which ranged from 18.85 to 41.08 %, comprised the majority of the total aggregate SOC contents. The woodland and grassland facilitated WSA stability and SOC protection, thus, promoting the natural restoration of vegetation by reducing artificial disturbances could effectively restore the ecology of and prevent soil erosion in karst regions.

  14. Positive Emotion Facilitates Audiovisual Binding

    OpenAIRE

    Kitamura, Miho S.; Watanabe, Katsumi; Kitagawa, Norimichi

    2016-01-01

    It has been shown that positive emotions can facilitate integrative and associative information processing in cognitive functions. The present study examined whether emotions in observers can also enhance perceptual integrative processes. We tested 125 participants in total for revealing the effects of emotional states and traits in observers on the multisensory binding between auditory and visual signals. Participants in Experiment 1 observed two identical visual disks moving toward each oth...

  15. The ITZ in concrete with natural and recycled aggregates: Study of microstructures based on image and SEM analysis

    OpenAIRE

    Bonifazi, G.; Capobianco, G.; Serranti, S.; Eggimann, M; Wagner, E; Di Maio, F.; Lotfi, S.

    2015-01-01

    Aim of this work was to investigate the microstructure of the Interfacial Transition Zone (ITZ) between cement paste and aggregate in concrete utilizing Scanning Electron Microscope (SEM) in order to identify possible effects on the ITZ related to different recipes and production parameters. SEM is an important tool to carry out concrete, cement and aggregate microstructure characterization. SEM imaging facilitates identification of elements in concrete. Thanks to the higher spatial resolutio...

  16. Credit, Money, and Aggregate Demand

    OpenAIRE

    Bernanke, Ben S.; Alan S. Blinder

    1988-01-01

    Standard models of aggregate demand treat money and credit asymmetrically; money is given a special status, while loans, bonds, and other debt instruments are lumped together in a "bond market" and suppressed by Walras' Law. This makes bank liabilities central to the monetary transmission mechanism, while giving no role to bank assets. We show how to modify a textbook IS-UI model so as to permit a more balanced treatment. As in Tobin (1969) and Brunner-Meltzer (1972), the key assumption is th...

  17. Strategy-proof Preference Aggregation

    OpenAIRE

    Bossert, Walter; Sprumont, Yves

    2012-01-01

    An aggregation rule maps each profile of individual strict preference orderings over a set of alternatives into a social ordering over that set. We call such a rule strategyproof if misreporting one’s preference never produces a social ordering that is strictly between the original ordering and one’s own preference. After describing a few examples of manipulable rules, we study in some detail three classes of strategy-proof rules: (i) rules based on a monotonic alteration of the majority rela...

  18. Inhomogeneous diffusion-limited aggregation

    Science.gov (United States)

    Selinger, Robin Blumberg; Nittmann, Johann; Stanley, H. E.

    1989-01-01

    It is demonstrated here that inhomogeneous diffusion-limited aggregation (DLA) model can be used to simulate viscous fingering in a medium with inhomogeneous permeability and homogeneous porosity. The medium consists of a pipe-pore square-lattice network in which all pores have equal volume and the pipes have negligible volume. It is shown that fluctuations in a DLA-based growth process may be tuned by noise reduction, and that fluctuations in the velocity of the moving interface are multiplicative in form.

  19. PERCOLATION OF RANDOM CYLINDER AGGREGATES

    Directory of Open Access Journals (Sweden)

    Dominique Jeulin

    2011-05-01

    Full Text Available The percolation threshold ρc of Boolean models of cylinders with their axis parallel to a given direction is studied by means of simulations. An efficient method of construction of percolating connected components was developed, and is applied to one or two scales Boolean model, in order to simulate the presence of aggregates. The invariance of the percolation threshold with respect to affine transformations in the common direction of the axis of cylinders is approximately satisfied on simulations. The prediction of the model (ρc close to 0.16 is consistent with experimental measurements on plasma spray coatings, which motivated this study.

  20. A Red List of Italian Saproxylic Beetles: taxonomic overview, ecological features and conservation issues (Coleoptera

    Directory of Open Access Journals (Sweden)

    Giuseppe Maria Carpaneto

    2015-12-01

    Full Text Available The main objectives of this review are: 1 the compilation and updating of a reference database for Italian saproxylic beetles, useful to assess the trend of their populations and communities in the next decades; 2 the identification of the major threats involving the known Italian species of saproxylic beetles; 3 the evaluation of the extinction risk for all known Italian species of saproxylic beetles; 4 the or- ganization of an expert network for studying and continuous updating of all known species of saproxylic beetle species in Italy; 5 the creation of a baseline for future evaluations of the trends in biodiversity conservation in Italy; 6 the assignment of ecological categories to all the Italian saproxylic beetles, useful for the aims of future researches on their communities and on forest environments. The assess- ments of extinction risk are based on the IUCN Red List Categories and Criteria and the most updated guidelines. The assessments have been carried out by experts covering different regions of Italy, and have been evaluated according to the IUCN standards. All the beetles whose larval biology is sufficiently well known as to be considered saproxylic have been included in the Red List, either the autochtho- nous species (native or possibly native to Italy or a few allochthonous species recently introduced or probably introduced to Italy in his- toric times. The entire national range of each saproxylic beetle species was evaluated, including large and small islands; for most species, the main parameters considered for evaluation were the extent of their geographical occurrence in Italy, and the number of known sites of presence. 2049 saproxylic beetle species (belonging to 66 families have been listed, assigned to a trophic category (Table 3 and 97% of them have been assessed. On the whole, threatened species (VU + EN + CR are 421 (Fig. 6, corresponding to 21 % of the 1988 as- sessed species; only two species are formally

  1. Colloid Release from Soil Aggregates

    DEFF Research Database (Denmark)

    Vendelboe, Anders Lindblad; Møldrup, Per; Schjønning, Per;

    2012-01-01

    The content of water-dispersible colloids (WDC) has a major impact on soil functions and structural stability. In addition, the presence of mobile colloids may increase the risk of colloid-facilitated transport of strongly sorbing environmental contaminants. The WDC content was measured in 39 soils...

  2. How We Think and Talk about Facilitation

    Science.gov (United States)

    Kato, Fumitoshi

    2010-01-01

    Over the past few years, the notion of "facilitation" has been increasingly gaining attention and acceptance in Japan, especially in the context of education and training. Today, Japanese educators think and talk about facilitation, even if it is not yet clear what facilitation is. Interestingly enough, the term "facilitation" does not exist in…

  3. Influence of mating and age on susceptibility of the beetle Anoplophora glabripennis to the fungal pathogen Metarhizium brunneum.

    Science.gov (United States)

    Fisher, Joanna J; Hajek, Ann E

    2016-05-01

    The age and life history of an insect can influence its susceptibility to pathogens. Reproduction can be costly and may trade off with immunity while it is generally assumed that immunity will decrease with increasing age through a process called immunosenescence. Fungal pathogens are used as biological control agents for a variety of insect pests, and Metarhizium brunneum is being developed to control the Asian longhorned beetle (Anoplophora glabripennis), an invasive wood-borer. Because adult female A. glabripennis take 1-2weeks to mature after eclosion and both sexes can be long-lived, we investigated how age and mating status would influence susceptibility of A. glabripennis to M. brunneum. Young (6.5day-old) unmated, mature (27-33day-old) mated and unmated, and old (57-71day-old) unmated and mated adults were inoculated with a lethal dose of M. brunneum. The presence of M. brunneum in the hemolymph was quantified and beetle mortality was monitored daily. There was a cost to reproduction for mated mature male and female beetles which died a median of 1.6-1.9days earlier than unmated beetles, while there was no effect of mating on susceptibility for old beetles. We found no evidence for immunosenescence in old beetles, as they did not die faster than young or mature beetles. Young unmated males however were more susceptible than mature or old unmated males, while there was no effect of age on susceptibility of unmated females. PMID:27103165

  4. The incidence and use of Oryctes virus for control of rhinoceros beetle in oil palm plantations in Malaysia.

    Science.gov (United States)

    Ramle, M; Wahid, M B; Norman, K; Glare, T R; Jackson, T A

    2005-05-01

    The rhinoceros beetle, Oryctes rhinoceros, has emerged as a serious pest of oil palm since the prohibition of burning as a method for maintaining estate hygiene in the 1990s. The abundance of beetles is surprising given that the Malay peninsula was the site of first discovery of the Oryctes virus, which has been used to effect good as a biological control agent in other regions. A survey of adult beetles was carried out throughout Malaysia using pheromone traps. Captured beetles were examined for presence of virus using both visual/microscopic examination and PCR detection methods. The survey indicated that Oryctes virus was common in Malaysia among the adult beetles. Viral DNA analysis was carried out after restriction with HindIII enzyme and indicated at least three distinct viral genotypes. Bioassays were used to compare the viral strains and demonstrate that one strain (type B) is the most virulent against both larvae and adults of the beetle. Virus type B has been cultured and released into healthy populations where another strain (type A) forms the natural background. Capture and examination of beetles from the release site and surrounding area has shown that the spread and persistence of the applied virus strain is accompanied by a reduction in palm frond damage. PMID:16039309

  5. Predisposition to bark beetle attack by root herbivores and associated pathogens: Roles in forest decline, gap formation, and persistence of endemic bark beetle populations

    DEFF Research Database (Denmark)

    Aukema, Brian H.; Zhu, Jun; Møller, Jesper;

    2010-01-01

    , however, due to the requirement of long-term monitoring and high degrees of spatial and temporal covariance. We censused more than 2700 trees annually over 7 years, and at the end of 17 years, in a mature red pine plantation. Trees were measured for the presence of bark beetles and wood borers that breed....... This interaction results in an expanding forest gap, with subsequent colonization by early-successional vegetation. Spatial position strongly affects the likelihood of tree mortality. A red pine is initially very likely to avoid attack by tree-killing Ips beetles, but attack becomes increasingly likely...... as the belowground complex spreads to neighboring trees and eventually make trees susceptible. This system is largely internally driven, as there are strong gap edge, but not stand-edge, effects. Additional stressors, such as drought, can provide an intermittent source of susceptible trees to Ips...

  6. Hit-and-run trophallaxis of small hive beetles.

    Science.gov (United States)

    Neumann, Peter; Naef, Jan; Crailsheim, Karl; Crewe, Robin M; Pirk, Christian W W

    2015-12-01

    Some parasites of social insects are able to exploit the exchange of food between nestmates via trophallaxis, because they are chemically disguised as nestmates. However, a few parasites succeed in trophallactic solicitation although they are attacked by workers. The underlying mechanisms are not well understood. The small hive beetle (=SHB), Aethina tumida, is such a parasite of honey bee, Apis mellifera, colonies and is able to induce trophallaxis. Here, we investigate whether SHB trophallactic solicitation is innate and affected by sex and experience. We quantified characteristics of the trophallactic solicitation in SHBs from laboratory-reared individuals that were either bee-naïve or had 5 days experience. The data clearly show that SHB trophallactic solicitation is innate and further suggest that it can be influenced by both experience and sex. Inexperienced SHB males begged more often than any of the other groups had longer breaks than their experienced counterparts and a longer soliciting duration than both experienced SHB males and females, suggesting that they start rather slowly and gain more from experience. Successful experienced females and males were not significantly different from each other in relation to successful trophallactic interactions, but had a significantly shorter soliciting duration compared to all other groups, except successful inexperienced females. Trophallactic solicitation success, feeding duration and begging duration were not significantly affected by either SHB sex or experience, supporting the notion that these behaviors are important for survival in host colonies. Overall, success seems to be governed by quality rather than quantity of interactions, thereby probably limiting both SHB energy investment and chance of injury (<1%). Trophallactic solicitation by SHBs is a singular example for an alternative strategy to exploit insect societies without requiring chemical disguise. Hit-and-run trophallaxis is an attractive test

  7. Utilization Possibility of Natural Aggregate Resources in Central Town of Tokat as Concrete Aggregate

    Directory of Open Access Journals (Sweden)

    S. I. Tutmaz

    2010-01-01

    Full Text Available In this study, aggregates of three quarries sampled from Tokat Province were tested to evaluate their suitability for concrete production. The aggregates were supplied from Yesilirmak River, and largely used in agricultural structures constructed in Tokat. Standard aggregate tests approved by Turkish Standards Institute were carried out to analyze the samples. Granulation, unit weight, specific weight, water absorption rate, resistance to frost, resistance against abrasion, ratio of fine materials, organic material contents and, mineralogical analysis of aggregates sampled from aggregate quarries were determined. Pressure resistance tests were conducted on concrete prepared by the aggregates. The results indicated that the aggregate granulation distribution of aggregate quarries evaluated was not suitable however other parameters determined were appropriate for concrete production. The resultant concrete had sufficient pressure resistance. The possible solutions to improve the improper characteristics of aggregates used in concrete were also determined and introduced with this study.

  8. First occurrence of western corn root worm beetles in the federal states Hesse and Rhineland-Palatinate (Germany, 2011

    Directory of Open Access Journals (Sweden)

    Dicke, Dominik

    2014-02-01

    Full Text Available In 2011, western corn root worm beetles were detected in the federal states Hesse (Groß-Gerau and Rhineland-Palatinate (Bodenheim for the first time. Control measures based on commission decision 2003/766/EG (Byrne, 2003 were conducted after detection in PAL-traps. Focus and safety zones were established. In Hesse, both focus and safety zones were treated with the insecticide Biscaya, due to the high number of 50 beetles which were detected in the PAL-traps. Since in Rhineland-Palatinate, only one beetle had been captured, only the focus zone was treated with the insecticide. After insecticide treatment, new PAL-traps were arranged like a close grid over the infested areas in both federal states. In each maize field in the focus- and safety zone further traps were placed and checked weekly until September 30th by supporting staff. Until the end of the monitoring in 2011 (September 30th further beetles were detected in the south of the area (district of Groß-Gerau, Hesse, were the first infestation had been discovered. However, in Rhineland-Palatinate no further beetles were detected that year. By the end of the monitoring 354 beetles in Hesse and one beetle in Rhineland-Palatinate had been captured in total. Subsequently the demarked zones in Hesse were extended. Taking into account the local circumstances, the new focus zone was delimited to include all the areas where beetles had been detected as well as the surrounding maize fields. In the focus zones the cultivation of maize was forbidden for the consecutive two years and a crop rotation with at least 50 percent maize was established in the safety zones. In 2012 no further beetles were captured in the infested region.

  9. Protein aggregates in Huntington's disease.

    Science.gov (United States)

    Arrasate, Montserrat; Finkbeiner, Steven

    2012-11-01

    Huntington's disease (HD) is an incurable neurodegenerative disease characterized by abnormal motor movements, personality changes, and early death. HD is caused by a mutation in the IT-15 gene that expands abnormally the number of CAG nucleotide repeats. As a result, the translated protein huntingtin contains disease-causing expansions of glutamines (polyQ) that make it prone to misfold and aggregate. While the gene and mutations that cause HD are known, the mechanisms underlying HD pathogenesis are not. Here we will review the state of knowledge of HD, focusing especially on a hallmark pathological feature-intracellular aggregates of mutant Htt called inclusion bodies (IBs). We will describe the role of IBs in the disease. We speculate that IB formation could be just one component of a broader coping response triggered by misfolded Htt whose efficacy may depend on the extent to which it clears toxic forms of mutant Htt. We will describe how IB formation might be regulated and which factors could determine different coping responses in different subsets of neurons. A differential regulation of IB formation as a function of the cellular context could, eventually, explain part of the neuronal vulnerability observed in HD. PMID:22200539

  10. Asphaltene Aggregation and Fouling Behavior

    Science.gov (United States)

    Derakhshesh, Marzie

    This thesis explored the properties of asphaltene nano-aggregates in crude oil and toluene based solutions and fouling at process furnace temperatures, and the links between these two phenomena. The link between stability of asphaltenes at ambient conditions and fouling at the conditions of a delayed coker furnace, at over 450 °C, was examined by blending crude oil with an aliphatic diluent in different ratios. The stability of the blends were measured using a S-value analyzer, then fouling rates were measured on electrically heated stainless steel 316 wires in an autoclave reactor. The less stable the blend, the greater the rate and extent of fouling. The most severe fouling occurred with the unstable asphaltenes. SEM imaging of the foulant illustrates very different textures, with the structure becoming more porous with lower stability. Under cross-polarized light, the coke shows the presence of mesophase in the foulant layer. These data suggest a correlation between the fouling rate at high temperature furnace conditions and the stability index of the crude oil. Three organic polysulfides were introduced to the crude oil to examine their effect on fouling. The polysulfides are able to reduce coking and carbon monoxide generation in steam crackers. The fouling results demonstrated that polysulfide with more sulfur content increased the amount of corrosion-fouling of the wire. Various additives, solvents, ultrasound, and heat were employed to attempt to completely disaggregate the asphaltene nano-aggregates in solution at room temperature. The primary analytical technique used to monitor the nano-aggregation state of the asphaltenes in solution was the UV-visible spectroscopy. The results indicate that stronger solvents, such as pyridine and quinoline, combined with ionic liquids yield a slight reduction in the apparent absorbance at longer wavelengths, indicative of a decrease in the nano-aggregate size although the magnitude of the decrease is not significant

  11. Phenotypes of non-attached Pseudomonas aeruginosa aggregates resemble surface attached biofilm.

    Directory of Open Access Journals (Sweden)

    Morten Alhede

    Full Text Available For a chronic infection to be established, bacteria must be able to cope with hostile conditions such as low iron levels, oxidative stress, and clearance by the host defense, as well as antibiotic treatment. It is generally accepted that biofilm formation facilitates tolerance to these adverse conditions. However, microscopic investigations of samples isolated from sites of chronic infections seem to suggest that some bacteria do not need to be attached to surfaces in order to establish chronic infections. In this study we employed scanning electron microscopy, confocal laser scanning microscopy, RT-PCR as well as traditional culturing techniques to study the properties of Pseudomonas aeruginosa aggregates. We found that non-attached aggregates from stationary-phase cultures have comparable growth rates to surface attached biofilms. The growth rate estimations indicated that, independently of age, both aggregates and flow-cell biofilm had the same slow growth rate as a stationary phase shaking cultures. Internal structures of the aggregates matrix components and their capacity to survive otherwise lethal treatments with antibiotics (referred to as tolerance and resistance to phagocytes were also found to be strikingly similar to flow-cell biofilms. Our data indicate that the tolerance of both biofilms and non-attached aggregates towards antibiotics is reversible by physical disruption. We provide evidence that the antibiotic tolerance is likely to be dependent on both the physiological states of the aggregates and particular matrix components. Bacterial surface-attachment and subsequent biofilm formation are considered hallmarks of the capacity of microbes to cause persistent infections. We have observed non-attached aggregates in the lungs of cystic fibrosis patients; otitis media; soft tissue fillers and non-healing wounds, and we propose that aggregated cells exhibit enhanced survival in the hostile host environment, compared with non-aggregated

  12. Stochastic facilitation in the brain?

    Science.gov (United States)

    Ward, Lawrence M.; Greenwood, Priscilla E.

    2016-05-01

    We describe the context for three unsolved problems of noise in the brain as well as provide some new results relevant to one of them. The problems are: are neural oscillations better described as noisy limit cycles or as noise-driven quasicycles, does noise facilitate synchronization and information transmission in the brain, and do noise-driven spatial patterns (quasipatterns) coexist with noise-driven quasicycles in the brain? We provide a few new results indicating that, in models at least, spatial quasipatterns of quasicycles can occur, and resemble patterns observed in other areas, such as predator-prey systems and chemical reactions.

  13. GIS-facilitated spatial narratives

    DEFF Research Database (Denmark)

    Møller-Jensen, Lasse; Jeppesen, Henrik; Kofie, Richard Y.

    2008-01-01

    thematically and narrative linking of a set of locations within an area. A spatial narrative that describes the - largely unsuccessful - history of Danish plantations on the Gold Coast (1788-1850) is implemented through the Google Earth client. This client is seen both as a type of media in itself for ‘home......-based' exploration of sites related to the narrative and as a tool that facilitates the design of spatial narratives before implementation within portable GIS devices. The Google Earth-based visualization of the spatial narrative is created by a Python script that outputs a web-accessible KML format file. The KML...

  14. Facilitating Collaboration through Design Games

    DEFF Research Database (Denmark)

    Brandt, Eva; Messeter, Jørn

    2004-01-01

    In recent years both companies and research communities call for collaborative work practices and user-centered approaches in various design fields. There are several challenges and issues to take into consideration. For instance there is a need to find ways of collaborating across various...... in collaboration with industrial partners and potential users, and use of the games in three educational settings.The overall aim of the design games is to help facilitate a user-centered design process for cross-disciplinary design groups early in the design process. Framing collaborative design...

  15. Temporal Dynamics of Corn Flea Beetle Populations Infested with Pantoea stewartii, Causal Agent of Stewart's Disease of Corn.

    Science.gov (United States)

    Esker, P D; Nutter, F W

    2003-02-01

    ABSTRACT In order to better understand the epidemiology of the Stewart's disease of corn pathosystem, quantitative information concerning the temporal dynamics of the amount of pathogen inoculum present in the form of Pantoea stewartii-infested corn flea beetles (Chaetocnema pulicaria) is needed. Temporal changes in the proportion of P. stewartii-infested corn flea beetle populations were monitored by testing individual corn flea beetles for the presence of P. stewartii using a peroxidase-labeled, enzyme-linked immunosorbent assay. Approximately 90 corn flea beetles were collected each week from seven locations in Iowa from September 1998 through October 2000 using sweep nets. The proportion of P. stewartii-infested beetles at the end of the 1998 growing season ranged from 0.04 to 0.19. In spring 1999, the proportion of overwintering adult corn flea beetles infested with P. stewartii ranged from 0.10 to 0.11 and did not differ significantly from the previous fall based on chi(2). During the 1999 corn-growing season, the proportion of infested corn flea beetles ranged from 0.04 to 0.86, with the highest proportions occurring in August. In fall 1999, the proportion of beetles infested with P. stewartii ranged from 0.20 to 0.77. In spring 2000, the proportion of overwintering adult corn flea beetles infested with P. stewartii ranged from 0.08 to 0.30; these proportions were significantly lower than the proportions observed in fall 1999 at Ames, Chariton, and Nashua. During the 2000 corn-growing season, the proportion of P. stewartii-infested corn flea beetles ranged from 0.08 to 0.53, and the highest observed proportions again occurred in August. Corn flea beetle populations sampled in late fall 2000 had proportions of infested beetles ranging from 0.08 to 0.20. This is the first study to quantify the temporal population dynamics of P. stewartii-infested C. pulicaria populations in hybrid corn and provides new quantitative information that should be useful in

  16. Functional response and numerical response of great spotted woodpecker Picoides major on Asian longhorned beetle Anoplophora glabripennis larvae

    OpenAIRE

    JIAO Zhen-Biao; Wan, Tao; Wen, Jun-Bao; HU Jia-Fu; Luo, You-Qing; ZHANG Lin-Sheng; FU Lin-Ju

    2008-01-01

    The Asian longhorned beetle Anoplophora glabripennis is a wood-boring beetle that, upon severe outbreaks, causes great damage in the artificial shelter-forest of the Three-Northern Areas. The Great Spotted Woodpecker Picoides major is one of the natural predators of A.glabripennis. P.major is also a common species in Wulate Qianqi of the Inner Mongolia Autonomous Region and is widely distributed in the artificial shelter-forest. The wood-boring beetle is an important food source of P.major, e...

  17. One-dimensional long-range diffusion-limited aggregation III -- The limit aggregate

    CERN Document Server

    Amir, Gideon

    2009-01-01

    In this paper we study the structure of the limit aggregate (the union of all finite-time aggregates) of the one-dimensional long range diffusion limited aggregation process defined in [arXiv:0910.4416] . We show (under some regularity conditions) that for walks with finite third moment the limit aggregate has renewal structure and positive density, while for walks with finite variance the renewal structure no longer exists and the limit aggregate has 0 density. We define a tree structure on the aggregates and show some results on the degrees and number of ends of these random trees.

  18. Association of Geosmithia fungi (Ascomycota: Hypocreales) with pine- and spruce-infesting bark beetles in Poland

    Czech Academy of Sciences Publication Activity Database

    Jankowiak, R.; Kolařík, Miroslav; Bilanski,, P.

    2014-01-01

    Roč. 11, OCT 2014 (2014), s. 71-79. ISSN 1754-5048 R&D Projects: GA ČR(CZ) GAP506/11/2302 Institutional support: RVO:61388971 Keywords : Insect-fungus interactions * Bark beetles * Ectosymbiosis Subject RIV: EE - Microbiology, Virology Impact factor: 2.929, year: 2014

  19. Characterization of two closely related α-amylase paralogs in the bark beetle, Ips typographus (L.)

    Czech Academy of Sciences Publication Activity Database

    Viktorinová, I.; Kučerová, Lucie; Böhmová, Marta; Henry, I.; Jindra, Marek; Doležal, Petr; Žurovcová, Martina; Žurovec, Michal

    2011-01-01

    Roč. 77, č. 4 (2011), s. 179-198. ISSN 0739-4462 EU Projects: European Commission(CZ) FP7/2007-2013 Institutional research plan: CEZ:AV0Z50070508 Keywords : bark beetle * intron polymorphism * α-amylase Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.361, year: 2011

  20. Management of Yellowmargined Leaf Beetle Microtheca ochroloma (Coleoptera: Chrysomelidae) Using Turnip as a Trap Crop.

    Science.gov (United States)

    Balusu, Rammohan; Rhodes, Elena; Liburd, Oscar; Fadamiro, Henry

    2015-12-01

    The yellowmargined leaf beetle, Microtheca ochroloma Stål, is a major pest of cruciferous vegetable crops in organic production systems. Very few organically acceptable management options are currently available for this pest. Field studies were conducted at a research station in Alabama and at a commercial organic vegetable farm in Florida to investigate the effectiveness of turnip, Brassica rapa rapa, as a trap crop for M. ochroloma. In the research station trial with cabbage planted as the cash crop, perimeter planting of turnip as a trap crop effectively reduced beetle numbers and crop damage below levels recorded in the control. During the first season of our on-farm trial, with napa cabbage and mustard as the cash crops, using turnip as a trap crop effectively reduced both beetle numbers and cash crop damage below levels found in the control plots, but economic damage was still high. In the second season, beetle populations were too low for significant differences in damage levels to occur between the trap crop and control plots. Together, these results suggest that turnip planted as a trap crop can be an effective control tactic for cruciferous crops, like cabbage, that are much less attractive to M. ochroloma than turnip. In crops, like mustard and napa cabbage, that are equally or only slightly less attractive than turnip, planting turnip as a trap crop would have to be used in combination with other tactics to manage M. ochroloma. PMID:26470380

  1. Investigation of the enzyme system of detoxification of insecticides in the Colorado beetle

    International Nuclear Information System (INIS)

    The activity of three enzymes systems of xenobiotic metabolism - cytochrome P-450-dependent monooxygenases, nonspecific esterases, and glutathione S-transferases - was investigated at various stages of the development of the Colorado beetle Leptinotarsa decemlineata. Substantial sex and ontogenetic differences in the content of cytochrome P-450, the position of the maxima of the CO-differential spectra of its reduced form, and the substrate specificity of cytochrome P-450 were demonstrated. An increase in the activity of nonspecific esterases with increasing age of Colorado beetle larvae was observed. The insecticide 1-naphtholenol methylcarbamate, which is metabolized by the system of cytochrome P-450-dependent monooxygenases, is more toxic at the larval stage of development in comparison with the imaginal stage, which is in good agreement with the activity of this system at different stages of development. The inhibitor of microsomal monooxygenases piperonyl butoxide more than doubles the toxicity of the insecticide in the Colorado beetle imago. The data presented are evidence of a different contribution of the systems of detoxification to the sensitivity of the Colorado beetle to insecticides at different stages of metamorphosis

  2. Low doses of ivermectin cause sensory and locomotor disorders in dung beetles

    Science.gov (United States)

    Verdú, José R.; Cortez, Vieyle; Ortiz, Antonio J.; González-Rodríguez, Estela; Martinez-Pinna, Juan; Lumaret, Jean-Pierre; Lobo, Jorge M.; Numa, Catherine; Sánchez-Piñero, Francisco

    2015-09-01

    Ivermectin is a veterinary pharmaceutical generally used to control the ecto- and endoparasites of livestock, but its use has resulted in adverse effects on coprophilous insects, causing population decline and biodiversity loss. There is currently no information regarding the direct effects of ivermectin on dung beetle physiology and behaviour. Here, based on electroantennography and spontaneous muscle force tests, we show sub-lethal disorders caused by ivermectin in sensory and locomotor systems of Scarabaeus cicatricosus, a key dung beetle species in Mediterranean ecosystems. Our findings show that ivermectin decreases the olfactory and locomotor capacity of dung beetles, preventing them from performing basic biological activities. These effects are observed at concentrations lower than those usually measured in the dung of treated livestock. Taking into account that ivermectin acts on both glutamate-gated and GABA-gated chloride ion channels of nerve and muscle cells, we predict that ivermectin’s effects at the physiological level could influence many members of the dung pat community. The results indicate that the decline of dung beetle populations could be related to the harmful effects of chemical contamination in the dung.

  3. 75 FR 81832 - Asian Longhorned Beetle; Quarantined Area and Regulated Articles

    Science.gov (United States)

    2010-12-29

    ..., 2010, we are adopting as a final rule the interim rule published at 75 FR 34320-34322 on June 17, 2010... (75 FR 34320-34322, Docket No. APHIS-2010- 0004), we amended the Asian longhorned beetle regulations... that was published at 75 FR 34320-34322 on June 17, 2010. Done in Washington, DC on December 22,...

  4. Atomic force microscopy study of nano-physiological response of ladybird beetles to photostimuli.

    Directory of Open Access Journals (Sweden)

    Natalia V Guz

    Full Text Available BACKGROUND: Insects are of interest not only as the most numerous and diverse group of animals but also as highly efficient bio-machines varying greatly in size. They are the main human competitors for crop, can transmit various diseases, etc. However, little study of insects with modern nanotechnology tools has been done. METHODOLOGY/PRINCIPAL FINDINGS: Here we applied an atomic force microscopy (AFM method to study stimulation of ladybird beetles with light. This method allows for measuring of the internal physiological responses of insects by recording surface oscillations in different parts of the insect at sub-nanometer amplitude level and sub-millisecond time. Specifically, we studied the sensitivity of ladybird beetles to light of different wavelengths. We demonstrated previously unknown blindness of ladybird beetles to emerald color (∼500nm light, while being able to see UV-blue and green light. Furthermore, we showed how one could study the speed of the beetle adaptation to repetitive flashing light and its relaxation back to the initial stage. CONCLUSIONS: The results show the potential of the method in studying insects. We see this research as a part of what might be a new emerging area of "nanophysiology" of insects.

  5. Side effects of kaolin particle films on apple orchard bug, beetle and spider communities

    NARCIS (Netherlands)

    Marko, V.; Bogya, S.; Kondorosy, E.; Blommers, L.H.M.

    2010-01-01

    The effects of multiple applications of hydrophobic kaolin particle film on apple orchard bug (Heteroptera), beetle (Coleoptera) and spider (Araneae) assemblages were studied in the Netherlands. Insecticide-free orchard plots served as a control. The kaolin applications significantly reduced the abu

  6. Characterization of a Pantoea stewartii TTSS gene required for persistence in its flea beetle vector

    Science.gov (United States)

    Stewart's bacterial wilt of maize is caused by Pantoea stewartii subsp. stewartii (Pnss), a bacterium that is transmitted by the flea beetle, Chaetocnema pulicaria. Few studies have focused on the molecular basis of the interactions of Pnss with its vector. Genome analyses indicated that Pnss carri...

  7. Spruce bark beetle (Ips typographus L.) infestation and Norway spruce status: is there a causal relationship?

    Czech Academy of Sciences Publication Activity Database

    Moravec, Ivo; Cudlín, Pavel; Polák, T.; Havlíček, František

    2002-01-01

    Roč. 8, - (2002), s. 255-264. ISSN 1211-7420 R&D Projects: GA MŠk OK 389 Institutional research plan: CEZ:AV0Z6087904 Keywords : bark beetle infestation * crown status * Picea abies Subject RIV: GK - Forestry

  8. ALKANES, METHYLALKANES, ALKENES AND ALKADIENES OF ADULT FLEA BEETLES, APHTHONA SPECIES

    Science.gov (United States)

    The adult beetles, Aphthona lacertosa and Aphthona nigriscutis, used as biocontrol agents for leafy spurge, had a complex mixture of hydrocarbons on their cuticular surface consisting of alkanes, methylalkanes, alkenes and alkadienes as determined by gas chromatography-mass spectrometry. A trace ...

  9. A Dung Beetle-like Leg and its Adaptive Neural Control

    DEFF Research Database (Denmark)

    Di Canio, Giuliano; Stoyanov, Stoyan; Larsen, Jørgen Christian;

    2016-01-01

    Dung beetles show fascinating locomotion abilities. They can use their legs to not only walk but also manipulate objects. Furthermore, they can perform their leg movements at a proper frequency with respect to their biomechanical properties and quickly adapt the movements to deal with external pe...

  10. A New foodweb based on microbes in calcitic caves: The Cansiliella (Beetles) case in Northern Italy

    OpenAIRE

    Paoletti Maurizio G.; Beggio Mattia; Dreon Angelo Leandro; Pamio Alberto; Gomiero Tiziano; Brilli Mauro; Dorigo Luca; Concheri Giuseppe; Squartini Andrea; Summers Engel Annette

    2011-01-01

    The troglobitic beetle, Cansiliella servadeii (Leptodirini), has specialized mouthparts modified for browsing and feeding under percolating water on moonmilk, a speleothem formation in Grotta della Foos, Italy. Results from analyses of stable isotopes of carbon and nitrogen suggest thatacquires and assimilates dissolved allochthonous organic carbon, inorganic nitrogen, and possibly phosphorus and other nutrients from the microbial fauna associated with moonmilk.

  11. Response of soil chemistry to forest dieback after bark beetle infestation

    Czech Academy of Sciences Publication Activity Database

    Kaňa, Jiří; Tahovská, K.; Kopáček, Jiří

    2013-01-01

    Roč. 113, 1-3 (2013), s. 369-383. ISSN 0168-2563 R&D Projects: GA AV ČR(CZ) KJB600960907 Institutional support: RVO:60077344 Keywords : bark beetle infestation * soil nutrient availability * soil sorption complex Subject RIV: DJ - Water Pollution ; Quality Impact factor: 3.730, year: 2013

  12. Beetles and the decline of the Old Kingdom: climate change in ancient Egypt

    Czech Academy of Sciences Publication Activity Database

    Bárta, M.; Bezděk, Aleš

    Praha : Czech Institute of Egyptology , Faculty of Arts, Charles University, 2008 - (Vymazalová, H.; Bárta, M.), s. 214-222 ISBN 978-80-7308-245-1 R&D Projects: GA AV ČR 1QS500070505 Institutional research plan: CEZ:AV0Z50070508 Keywords : Beetles * Egypt * archaeology Subject RIV: EG - Zoology

  13. White Spruce Regeneration Following a Major Spruce Beetle Outbreak in Forests on the Kenai Peninsula, Alaska

    Science.gov (United States)

    Between 1987 and 2000, a spruce beetle (Dendroctonus rufipennis) epidemic infested 1.19 million hectares of spruce (Picea spp.) forests in Alaska, killing most of the large diameter trees. We evaluated whether these forests would recover to their pre-outbreak density, and determined the site conditi...

  14. Hybrid engineered materials with high water-collecting efficiency inspired by Namib Desert beetles.

    Science.gov (United States)

    Zhu, Hai; Guo, Zhiguang

    2016-05-21

    Inspired by Namib Desert beetles, a hybrid superhydrophobic surface was fabricated, showing highly efficient fog harvesting with a water collection rate (WCR) of 1309.9 mg h(-1) cm(-2). And, the surface possessed an excellent robustness and self-cleaning property. PMID:27125658

  15. Seasonal activity of the small hive beetle, Aethina tumida, as estimated by baited flight traps

    Science.gov (United States)

    Seasonal variation in flight activity of the small hive beetle was monitored at two sites in north-central Florida, one near colonies of the European honeybee and the other far removed from bee colonies. Activity was monitored by flight traps baited with fermenting pollen dough that had been inocul...

  16. The complete mitochondrial genome of the desert darkling beetle Asbolus verrucosus (Coleoptera, Tenebrionidae).

    Science.gov (United States)

    Rider, Stanley Dean

    2016-07-01

    The complete mitochondrial genome of the desert darkling beetle Asbolus verrucosus (LeConte, 1851) was sequenced using paired-end technology to an average depth of 42,111× and assembled using De Bruijn graph-based methods. The genome is 15,828 bp in length and conforms to the basal arthropod mitochondrial gene composition with the same gene orders and orientations as other darkling beetle mitochondria. This arrangement includes a control region, 22 tRNA genes, 2 rRNA genes and 13 protein-coding genes. The main coding strand is probably replicated as the lagging strand (GC skew of -0.36 and AT skew of +0.19). Phylogenomics analyses are consistent with taxonomic classifications and indicate that Tenebrio molitor is the closest relative that has a completely sequenced mitochondrial genome available for analysis. This is the first fully assembled mitogenome sequence for a darkling beetle in the subfamily Pimeliinae and will be useful for population studies on members of this ecologically important group of beetles. PMID:26016880

  17. Influence of Population Density on Offspring Number and Size in Burying Beetles

    Science.gov (United States)

    Rauter, Claudia M.

    2010-01-01

    This laboratory exercise investigates the influence of population density on offspring number and size in burying beetles. Students test the theoretical predictions that brood size declines and offspring size increases when competition over resources becomes stronger with increasing population density. Students design the experiment, collect and…

  18. Investigation of acoustic sensors to detect coconut rhinoceros beetle in Guam

    Science.gov (United States)

    The coconut rhinoceros beetle, Oryctes rhinoceros, was accidentally introduced into Guam last year and now threatens the Island’s forests and tourist industry. These large insects can be detected easily with acoustic sensors, and procedures are being developed to incorporate acoustic technology int...

  19. Stenusine, an antimicrobial agent in the rove beetle genus Stenus (Coleoptera, Staphylinidae)

    Science.gov (United States)

    Lusebrink, Inka; Dettner, Konrad; Seifert, Karlheinz

    2008-08-01

    Stenusine is well known as the alkaloid, discharged by the rove beetle, genus Stenus Latreille (Coleoptera, Staphylinidae). The Stenus beetles employ the alkaloid as an escape mechanism when on water surfaces. In the case of danger, they lower their abdomen and emit stenusine from their pygidial glands. Stenusine shows a low surface tension and therefore a high spreading pressure; these properties propel the beetle quickly over the water. Many Steninae do not live in habitats with open waters, but in detritus, leaf litter, mosses, etc. This raises the possibility that stenusine might also have another function, e.g., as antibiotic or fungicide. Stenus beetles show an intense grooming behaviour. With gas chromatography mass spectrometry analyses we could prove that they cover themselves with their secretion. To tests its antimicrobial properties we conducted agar diffusion tests with stenusine and norstenusine, another substance that is abundant in most Stenus species. Both compounds have an antimicrobial effect on entomopathogenic bacteria and fungi. Stenusine not only allows for an extraordinary method of locomotion on water surfaces, it also protects the Steninae from being infested with microorganisms.

  20. Are bark beetles chewing up our forests? What about our coffee?

    Science.gov (United States)

    A write-up for the Elsevier SciTech Connect blog on the recently published book entitled "Bark Beetles: Biology and Ecology of Native and Invasive Species," edited by Fernando E. Vega and Richard W. Hofstetter. The book was published by Academic Press in January 2015....