WorldWideScience

Sample records for arthropod vectors

  1. Arthropods vector grapevine trunk disease pathogens.

    Science.gov (United States)

    Moyo, P; Allsopp, E; Roets, F; Mostert, L; Halleen, F

    2014-10-01

    Arthropod-mediated dispersal of pathogens is known in many cropping systems but has never been demonstrated for grapevine trunk disease pathogens. Arthropods from vineyards were screened for the presence of pathogens associated with Petri disease and esca using cultural and molecular techniques. The ability of the most abundant pathogen-carrying species to inoculate healthy grapevine vascular tissues was also determined. Millipedes and ants were allowed to associate with a DsRed- Express-transformed Phaeomoniella chlamydospora, after which they were exposed to freshly pruned healthy grapevines under controlled conditions and wounds were monitored for subsequent infection. In addition, the possibility of millipede excreta, commonly found on pruning wounds in the field, to act as inoculum source was determined. A diverse arthropod fauna was associated with declining grapevines and many of these carried trunk disease pathogens. However, spiders, the ant Crematogaster peringueyi, and the millipede Ommattoiulus moreleti were the most abundant pathogen carriers. The ant and millipede species fed on pruning wound sap and effectively transmitted trunk disease pathogens. Millipede excreta contained viable spores of Phaeomoniella chlamydospora and may serve as an inoculum source. Numerous arthropods, including beneficial predators, are potential vectors of grapevine trunk disease pathogens. Our results highlight the need for an integrated approach, including targeted management of ants and millipedes at the time of pruning, to limit the spread of grapevine trunk diseases. PMID:24624953

  2. Antiviral responses of arthropod vectors: an update on recent advances.

    Science.gov (United States)

    Rückert, Claudia; Bell-Sakyi, Lesley; Fazakerley, John K; Fragkoudis, Rennos

    2014-01-01

    Arthropod vectors, such as mosquitoes, ticks, biting midges and sand flies, transmit many viruses that can cause outbreaks of disease in humans and animals around the world. Arthropod vector species are invading new areas due to globalisation and environmental changes, and contact between exotic animal species, humans and arthropod vectors is increasing, bringing with it the regular emergence of new arboviruses. For future strategies to control arbovirus transmission, it is important to improve our understanding of virus-vector interactions. In the last decade knowledge of arthropod antiviral immunity has increased rapidly. RNAi has been proposed as the most important antiviral response in mosquitoes and it is likely to be the most important antiviral response in all arthropods. However, other newly-discovered antiviral strategies such as melanisation and the link between RNAi and the JAK/STAT pathway via the cytokine Vago have been characterised in the last few years. This review aims to summarise the most important and most recent advances made in arthropod antiviral immunity. PMID:25674592

  3. Antiviral responses of arthropod vectors: an update on recent advances.

    Science.gov (United States)

    Rückert, Claudia; Bell-Sakyi, Lesley; Fazakerley, John K; Fragkoudis, Rennos

    2014-01-01

    Arthropod vectors, such as mosquitoes, ticks, biting midges and sand flies, transmit many viruses that can cause outbreaks of disease in humans and animals around the world. Arthropod vector species are invading new areas due to globalisation and environmental changes, and contact between exotic animal species, humans and arthropod vectors is increasing, bringing with it the regular emergence of new arboviruses. For future strategies to control arbovirus transmission, it is important to improve our understanding of virus-vector interactions. In the last decade knowledge of arthropod antiviral immunity has increased rapidly. RNAi has been proposed as the most important antiviral response in mosquitoes and it is likely to be the most important antiviral response in all arthropods. However, other newly-discovered antiviral strategies such as melanisation and the link between RNAi and the JAK/STAT pathway via the cytokine Vago have been characterised in the last few years. This review aims to summarise the most important and most recent advances made in arthropod antiviral immunity.

  4. Herbivore arthropods benefit from vectoring plant viruses

    NARCIS (Netherlands)

    Belliure, B.; Janssen, A.; Maris, P.C.; Peters, D.; Sabelis, M.W.

    2005-01-01

    Plants infected with pathogens often attract the pathogens' vectors, but it is not clear if this is advantageous to the vectors. We therefore quantified the direct and indirect (through the host plant) effects of a pathogen on its vector. A positive direct effect of the plant-pathogenic Tomato spott

  5. [Effects of plant viruses on vector and non-vector herbivorous arthropods and their natural enemies: a mini review].

    Science.gov (United States)

    He, Xiao-Chan; Xu, Hong-Xing; Zhou, Xiao-Jun; Zheng, Xu-Song; Sun, Yu-Jian; Yang, Ya-Jun; Tian, Jun-Ce; Lü, Zhong-Xian

    2014-05-01

    Plant viruses transmitted by arthropods, as an important biotic factor, may not only directly affect the yield and quality of host plants, and development, physiological characteristics and ecological performances of their vector arthropods, but also directly or indirectly affect the non-vector herbivorous arthropods and their natural enemies in the same ecosystem, thereby causing influences to the whole agro-ecosystem. This paper reviewed the progress on the effects of plant viruses on herbivorous arthropods, including vector and non-vector, and their natural enemies, and on their ecological mechanisms to provide a reference for optimizing the management of vector and non-vector arthropod populations and sustainable control of plant viruses in agro-ecosystem.

  6. Francisella-Arthropod vector interaction and its role in patho-adaptation to infect mammals

    Directory of Open Access Journals (Sweden)

    Yousef eAbu Kwaik

    2011-02-01

    Full Text Available Francisella tularensis is a Gram-negative, intracellular, zoonotic bacterium, and is the causative agent of tularemia in a broad host range. Arthropods such as ticks, mosquitoes, and flies maintain F. tularensis in nature by transmitting the bacteria among small mammals. While the tick is largely believed to be a biological vector of F. tularensis, transmission by mosquitoes and flies is largely believed to be mechanical on the mouthpart through interrupted feedings. However, the mechanism of infection of the vectors by F. tularensis is not well understood. Since F. tularensis has not been localized in the salivary gland of the primary human biting ticks, it is thought that bacterial transmission by ticks is through mechanical inoculation of tick feces containing F. tularensis into the skin wound. D. melanogaster is an established arthropod-vector model of tularemia, where F. tularensis infects hemocytes, and is found in hemolymph, as seen in ticks. In addition, phagosome biogenesis and robust intracellular proliferation of F. tularensis in arthropod-derived cells are similar to that in mammalian macrophages. Furthermore, bacterial factors required for infectivity of mammals are often required for infectivity of the fly by F. tularensis. Several host factors that contribute to F. tularensis intracellular pathogenesis in D. melanogaster have been identified, and F. tularensis targets some of the evolutionarily conserved eukaryotic processes to enable intracellular survival and proliferation in evolutionarily distant hosts

  7. Surveillance of arthropod vector-borne infectious diseases using remote sensing techniques: a review.

    Directory of Open Access Journals (Sweden)

    Satya Kalluri

    2007-10-01

    Full Text Available Epidemiologists are adopting new remote sensing techniques to study a variety of vector-borne diseases. Associations between satellite-derived environmental variables such as temperature, humidity, and land cover type and vector density are used to identify and characterize vector habitats. The convergence of factors such as the availability of multi-temporal satellite data and georeferenced epidemiological data, collaboration between remote sensing scientists and biologists, and the availability of sophisticated, statistical geographic information system and image processing algorithms in a desktop environment creates a fertile research environment. The use of remote sensing techniques to map vector-borne diseases has evolved significantly over the past 25 years. In this paper, we review the status of remote sensing studies of arthropod vector-borne diseases due to mosquitoes, ticks, blackflies, tsetse flies, and sandflies, which are responsible for the majority of vector-borne diseases in the world. Examples of simple image classification techniques that associate land use and land cover types with vector habitats, as well as complex statistical models that link satellite-derived multi-temporal meteorological observations with vector biology and abundance, are discussed here. Future improvements in remote sensing applications in epidemiology are also discussed.

  8. Surveillance of arthropod vector-borne infectious diseases using remote sensing techniques: a review.

    Science.gov (United States)

    Kalluri, Satya; Gilruth, Peter; Rogers, David; Szczur, Martha

    2007-10-26

    Epidemiologists are adopting new remote sensing techniques to study a variety of vector-borne diseases. Associations between satellite-derived environmental variables such as temperature, humidity, and land cover type and vector density are used to identify and characterize vector habitats. The convergence of factors such as the availability of multi-temporal satellite data and georeferenced epidemiological data, collaboration between remote sensing scientists and biologists, and the availability of sophisticated, statistical geographic information system and image processing algorithms in a desktop environment creates a fertile research environment. The use of remote sensing techniques to map vector-borne diseases has evolved significantly over the past 25 years. In this paper, we review the status of remote sensing studies of arthropod vector-borne diseases due to mosquitoes, ticks, blackflies, tsetse flies, and sandflies, which are responsible for the majority of vector-borne diseases in the world. Examples of simple image classification techniques that associate land use and land cover types with vector habitats, as well as complex statistical models that link satellite-derived multi-temporal meteorological observations with vector biology and abundance, are discussed here. Future improvements in remote sensing applications in epidemiology are also discussed.

  9. Lights, camera and action: vertebrate skin sets the stage for immune cell interaction with arthropod-vectored pathogens

    Directory of Open Access Journals (Sweden)

    Shu Zhen eChong

    2013-09-01

    Full Text Available Despite increasing studies targeted at host-pathogen interactions, vector-borne diseases remain one of the largest economic health burdens worldwide. Such diseases are vectored by hematophagous arthropods that deposit pathogens into the vertebrate host’s skin during a blood meal. These pathogens spend a substantial amount of time in the skin that allows for interaction with cutaneous immune cells, suggesting a window of opportunity for development of vaccine strategies. In particular, the recent availability of intravital imaging approaches has provided further insights into immune cell behavior in living tissues. Here, we discuss how such intravital imaging studies have contributed to our knowledge of cutaneous immune cell behavior and specifically, towards pathogen and tissue trauma from the arthropod bite. We also suggest future imaging approaches that may aid in better understanding of the complex interplay between arthropod-vectored pathogens and cutaneous immunity that could lead to improved therapeutic strategies.

  10. Disentangling Vector-Borne Transmission Networks: A Universal DNA Barcoding Method to Identify Vertebrate Hosts from Arthropod Bloodmeals

    DEFF Research Database (Denmark)

    Alcaide, Miguel; Rico, Ciro; Ruiz, Santiago;

    2009-01-01

    Emerging infectious diseases represent a challenge for global economies and public health. About one fourth of the last pandemics have been originated by the spread of vector-borne pathogens. In this sense, the advent of modern molecular techniques has enhanced our capabilities to understand vector......-host interactions and disease ecology. However, host identification protocols have poorly profited of international DNA barcoding initiatives and/or have focused exclusively on a limited array of vector species. Therefore, ascertaining the potential afforded by DNA barcoding tools in other vector-host systems...... of human and veterinary importance would represent a major advance in tracking pathogen life cycles and hosts. Here, we show the applicability of a novel and efficient molecular method for the identification of the vertebrate host’s DNA contained in the midgut of blood-feeding arthropods. To this end, we...

  11. Tomato spotted wilt virus benefits a non-vector arthropod, Tetranychus urticae, by modulating different plant responses in tomato.

    Directory of Open Access Journals (Sweden)

    Punya Nachappa

    Full Text Available The interaction between plant viruses and non-vector arthropod herbivores is poorly understood. However, there is accumulating evidence that plant viruses can impact fitness of non-vector herbivores. In this study, we used oligonucleotide microarrays, phytohormone, and total free amino acid analyses to characterize the molecular mechanisms underlying the interaction between Tomato spotted wilt virus (TSWV and a non-vector arthropod, twospotted spider mite (Tetranychusurticae, on tomato plants, Solanumlycopersicum. Twospotted spider mites showed increased preference for and fecundity on TSWV-infected plants compared to mock-inoculated plants. Transcriptome profiles of TSWV-infected plants indicated significant up-regulation of salicylic acid (SA-related genes, but no apparent down-regulation of jasmonic acid (JA-related genes which could potentially confer induced resistance against TSM. This suggests that there was no antagonistic crosstalk between the signaling pathways to influence the interaction between TSWV and spider mites. In fact, SA- and JA-related genes were up-regulated when plants were challenged with both TSWV and the herbivore. TSWV infection resulted in down-regulation of cell wall-related genes and photosynthesis-associated genes, which may contribute to host plant susceptibility. There was a three-fold increase in total free amino acid content in virus-infected plants compared to mock-inoculated plants. Total free amino acid content is critical for arthropod nutrition and may, in part, explain the apparent positive indirect effect of TSWV on spider mites. Taken together, these data suggest that the mechanism(s of increased host suitability of TSWV-infected plants to non-vector herbivores is complex and likely involves several plant biochemical processes.

  12. Surveillance of arthropod vector-borne infectious diseases using remote sensing techniques: a review.

    OpenAIRE

    Satya Kalluri; Peter Gilruth; David Rogers; Martha Szczur

    2007-01-01

    Epidemiologists are adopting new remote sensing techniques to study a variety of vector-borne diseases. Associations between satellite-derived environmental variables such as temperature, humidity, and land cover type and vector density are used to identify and characterize vector habitats. The convergence of factors such as the availability of multi-temporal satellite data and georeferenced epidemiological data, collaboration between remote sensing scientists and biologists, and the availabi...

  13. Rickettsial pathogens and arthropod vectors of medical and veterinary significance on Kwajalein Atoll and Wake Island

    Directory of Open Access Journals (Sweden)

    Durden, L.

    2012-05-01

    Full Text Available Modern surveys of ectoparasites and potential vector-borne pathogens in the Republic of the Marshall Islands and Wake Island are poorly documented. We report on field surveys of ectoparasites from 2010 with collections from dogs, cats, and rats. Five ectoparasites were identified: the cat flea Ctenocephalides felis, a sucking louse Hoplopleura pacifica, the mites Laelaps nuttalli and Radfordia ensifera, and the brown dog tickRhipicephalus sanguineus. Ectoparasites were screened for rickettsial pathogens. DNA from Anaplasma platys, a Coxiella symbiont of Rhipicephalus sanguineus, anda Rickettsia sp. were identified by PCR and DNA sequencing from ticks and fleas on Kwajalein Atoll. An unidentified spotted fever group Rickettsia was detected in a pool of Laelaps nuttalli and Hoplopleura pacifica from Wake Island. The records of Hoplopleura pacifica, Laelaps nuttalli, and Radfordia ensifera and the pathogens are new for Kwajalein Atoll and Wake Island.

  14. Sloth biology: an update on their physiological ecology, behavior and role as vectors of arthropods and arboviruses

    Directory of Open Access Journals (Sweden)

    Gilmore D.P.

    2001-01-01

    Full Text Available This is a review of the research undertaken since 1971 on the behavior and physiological ecology of sloths. The animals exhibit numerous fascinating features. Sloth hair is extremely specialized for a wet tropical environment and contains symbiotic algae. Activity shows circadian and seasonal variation. Nutrients derived from the food, particularly in Bradypus, only barely match the requirements for energy expenditure. Sloths are hosts to a fascinating array of commensal and parasitic arthropods and are carriers of various arthropod-borne viruses. Sloths are known reservoirs of the flagellate protozoan which causes leishmaniasis in humans, and may also carry trypanosomes and the protozoan Pneumocystis carinii.

  15. The Bartonella quintana Extracytoplasmic Function Sigma Factor RpoE Has a Role in Bacterial Adaptation to the Arthropod Vector Environment

    Science.gov (United States)

    Abromaitis, Stephanie

    2013-01-01

    Bartonella quintana is a vector-borne bacterial pathogen that causes fatal disease in humans. During the infectious cycle, B. quintana transitions from the hemin-restricted human bloodstream to the hemin-rich body louse vector. Because extracytoplasmic function (ECF) sigma factors often regulate adaptation to environmental changes, we hypothesized that a previously unstudied B. quintana ECF sigma factor, RpoE, is involved in the transition from the human host to the body louse vector. The genomic context of B. quintana rpoE identified it as a member of the ECF15 family of sigma factors found only in alphaproteobacteria. ECF15 sigma factors are believed to be the master regulators of the general stress response in alphaproteobacteria. In this study, we examined the B. quintana RpoE response to two stressors that are encountered in the body louse vector environment, a decreased temperature and an increased hemin concentration. We determined that the expression of rpoE is significantly upregulated at the body louse (28°C) versus the human host (37°C) temperature. rpoE expression also was upregulated when B. quintana was exposed to high hemin concentrations. In vitro and in vivo analyses demonstrated that RpoE function is regulated by a mechanism involving the anti-sigma factor NepR and the response regulator PhyR. The ΔrpoE ΔnepR mutant strain of B. quintana established that RpoE-mediated transcription is important in mediating the tolerance of B. quintana to high hemin concentrations. We present the first analysis of an ECF15 sigma factor in a vector-borne human pathogen and conclude that RpoE has a role in the adaptation of B. quintana to the hemin-rich arthropod vector environment. PMID:23564167

  16. Development of genetic system to inactivate a Borrelia turicatae surface protein selectively produced within the salivary glands of the arthropod vector.

    Directory of Open Access Journals (Sweden)

    Job E Lopez

    Full Text Available BACKGROUND: Borrelia turicatae, an agent of tick-borne relapsing fever, is an example of a pathogen that can adapt to disparate conditions found when colonizing the mammalian host and arthropod vector. However, little is known about the genetic factors necessary during the tick-mammalian infectious cycle, therefore we developed a genetic system to transform this species of spirochete. We also identified a plasmid gene that was up-regulated in vitro when B. turicatae was grown in conditions mimicking the tick environment. This 40 kilodalton protein was predicted to be surface localized and designated the Borrelia repeat protein A (brpA due to the redundancy of the amino acid motif Gln-Gly-Asn-Val-Glu. METHODOLOGY/PRINCIPAL FINDINGS: Quantitative reverse-transcriptase polymerase chain reaction using RNA from B. turicatae infected ticks and mice indicated differential regulation of brpA during the tick-mammalian infectious cycle. The surface localization was determined, and production of the protein within the salivary glands of the tick was demonstrated. We then applied a novel genetic system for B. turicatae to inactivate brpA and examined the role of the gene product for vector colonization and the ability to establish murine infection. CONCLUSIONS/SIGNIFICANCE: These results demonstrate the complexity of protein production in a population of spirochetes within the tick. Additionally, the development of a genetic system is important for future studies to evaluate the requirement of specific B. turicatae genes for vector colonization and transmission.

  17. Toxicity and repellency of plant essential oils against the arthropod disease vectors Phlebotomus papatasi and Ixodes scapularis

    Science.gov (United States)

    The sand fly Phlebotomus papatasi is an important blood feeder and the main vector of the trypanosomatid protozoa Leishmania major, which causes leishmaniasis in parts of the Afro-Eurasian region. The black- legged tick Ixodes scapularis is the primary tick vector of the bacterium Borrelia burgdorfe...

  18. Full-genome characterisation of Orungo, Lebombo and Changuinola viruses provides evidence for co-evolution of orbiviruses with their arthropod vectors.

    Directory of Open Access Journals (Sweden)

    Fauziah Mohd Jaafar

    Full Text Available The complete genomes of Orungo virus (ORUV, Lebombo virus (LEBV and Changuinola virus (CGLV were sequenced, confirming that they each encode 11 distinct proteins (VP1-VP7 and NS1-NS4. Phylogenetic analyses of cell-attachment protein 'outer-capsid protein 1' (OC1, show that orbiviruses fall into three large groups, identified as: VP2(OC1, in which OC1 is the 2nd largest protein, including the Culicoides transmitted orbiviruses; VP3(OC1, which includes the mosquito transmitted orbiviruses; and VP4(OC1 which includes the tick transmitted viruses. Differences in the size of OC1 between these groups, places the T2 'subcore-shell protein' as the third largest protein 'VP3(T2' in the first of these groups, but the second largest protein 'VP3(T2' in the other two groups. ORUV, LEBV and CGLV all group with the Culicoides-borne VP2(OC1/VP3(T2 viruses. The G+C content of the ORUV, LEBV and CGLV genomes is also similar to that of the Culicoides-borne, rather than the mosquito-borne, or tick borne orbiviruses. These data suggest that ORUV and LEBV are Culicoides- rather than mosquito-borne. Multiple isolations of CGLV from sand flies suggest that they are its primary vector. OC1 of the insect-borne orbiviruses is approximately twice the size of the equivalent protein of the tick borne viruses. Together with internal sequence similarities, this suggests its origin by duplication (concatermerisation of a smaller OC1 from an ancestral tick-borne orbivirus. Phylogenetic comparisons showing linear relationships between the dates of evolutionary-separation of their vector species, and genetic-distances between tick-, mosquito- or Culicoides-borne virus-groups, provide evidence for co-evolution of the orbiviruses with their arthropod vectors.

  19. Novel identification of Dermacentor variabilis Arp2/3 complex and its role in rickettsial infection of the arthropod vector.

    Directory of Open Access Journals (Sweden)

    Natthida Petchampai

    Full Text Available Tick-borne spotted fever group (SFG Rickettsia species must be able to infect both vertebrate and arthropod host cells. The host actin-related protein 2/3 (Arp2/3 complex is important in the invasion process and actin-based motility for several intracellular bacteria, including SFG Rickettsia in Drosophila and mammalian cells. To investigate the role of the tick Arp2/3 complex in tick-Rickettsia interactions, open reading frames of all subunits of the protein including Arp2, Arp3, ARPC1, ARPC2, ARPC3, ARPC4, and ARPC5 were identified from Dermacentor variabilis. Amino acid sequence analysis showed variation (ranging from 25-88% in percent identity compared to the corresponding subunits of the complex from Drosophila melanogaster, Mus musculus, Homo sapiens, and Saccharomyces cerevisiae. Potential ATP binding sites were identified in D. variabilis (Dv Arp2 and Arp3 subunits as well as five putative WD (Trp-Asp motifs which were observed in DvARPC1. Transcriptional profiles of all subunits of the DvArp2/3 complex revealed greater mRNA expression in both Rickettsia-infected and -uninfected ovary compared to midgut and salivary glands. In response to R. montanensis infection of the tick ovary, the mRNA level of only DvARPC4 was significantly upregulated compared to uninfected tissues. Arp2/3 complex inhibition bioassays resulted in a decrease in the ability of R. montanensis to invade tick tissues with a significant difference in the tick ovary, indicating a role for the Arp2/3 complex in rickettsial invasion of tick cells. Characterization of tick-derived molecules associated with rickettsial infection is imperative in order to better comprehend the ecology of tick-borne rickettsial diseases.

  20. Fitness Cost of Litomosoides sigmodontis Filarial Infection in Mite Vectors; Implications of Infected Haematophagous Arthropod Excretory Products in Host-Vector Interactions

    Directory of Open Access Journals (Sweden)

    Adélaïde Nieguitsila

    2013-01-01

    Full Text Available Filariae are a leading cause of infections which are responsible for serious dermatological, ocular, and vascular lesions. Infective third stage larvae (L3 are transmitted through the bite of a haematophagous vector. Litomosoides sigmodontis is a well-established model of filariasis in the mouse, with the vector being the mite Ornithonyssus bacoti. The aim of the study was to analyse the filarial infection in mites to determine the consequences of filarial infection in the blood-feeding and the reproduction of mites as well as in the regulation of vector-induced inflammation in the mouse skin. Firstly, L3 are unevenly distributed throughout the host population and the majority of the population harbours a moderate infection (1 to 6 L3. Filarial infection does not significantly affect the probing delay for blood feeding. The number of released protonymphs is lower in infected mites but is not correlated with the L3 burden. Finally, induced excreted proteins from infected mites but not from uninfected mites stimulate TNF-α and the neutrophil-chemoattractant KC production by antigen-presenting cells (APCs. Altogether, these results describe the modification of the mite behavior under filarial infection and suggest that the immunomodulatory capacity of the mite may be modified by the presence of the parasite, hindering its defensive ability towards the vertebrate host.

  1. Do chimpanzees (Pan troglodytes schweinfurthii) exhibit sleep related behaviors that minimize exposure to parasitic arthropods? A preliminary report on the possible anti-vector function of chimpanzee sleeping platforms.

    Science.gov (United States)

    Samson, David R; Muehlenbein, Michael P; Hunt, Kevin D

    2013-01-01

    Great apes spend half of their lives in a nightly "nest" or sleeping platform (SP), a complex object created by modifying foliage, which functions as a stable substrate on which to sleep. Of the several purported functions of SPs, one hypothesis is that they protect against parasitic infection. Here we investigate the role of SP site choice in avoiding molestation by arthropods. This study presents preliminary data on the insect-repellent properties of preferred sleeping tree species Cynometra alexandri. Insect traps were deployed in gallery forest habitats in which chimpanzees typically "nest." We compared traps placed adjacent to SPs artificially manufactured with C. alexandri trees to an open area within the same habitat. Multiple measures of arthropod counts indicate that simulated C. alexandri SP sites have fewer arthropods than similar non-SP sites. Volatile compounds secreted by C. alexandri foliage are hypothesized to repel annoying arthropods and/or mask chimpanzee olfactory signals. Of the total insects captured (n = 6,318), n = 145 were mosquitoes. Of the total mosquitoes captured, n = 47 were identified as Anopheles (female, n = 12). The prominent malarial vector Anopheles gambiae was identified among the captured mosquito sample. These results suggest that the presence of broken branches of the tree species C. alexandri reduce the amount of insects a chimpanzee is exposed to throughout a night's sleep. This great ape behavioral and socio-technological adaptation may have evolved, in part, to increase quality of sleep as well as decrease exposure to vectors of disease. PMID:23011513

  2. Arthropod vaccines.

    Science.gov (United States)

    Lee, R; Opdebeeck, J P

    1999-03-01

    Antigens located in the midgut of the tick are hidden from the host's immune system. Egg production of ticks can be reduced when ticks are fed on animals vaccinated with midgut antigens of the tick, and a subunit vaccine formulated with the recombinant antigen Bm86 is now available that can reduce the number of ticks infesting cattle grazing on pasture. Midgut antigens used in vaccines against insects that transmit pathogenic organisms to humans have not been as effective in reducing insect fecundity and an alternative approach may be necessary. Transmission-blocking vaccines directed at interfering with the vector-pathogen interaction could result in loss of vector competence and block the spread of disease-causing organisms. PMID:10198800

  3. Vertical T-maze Choice Assay for Arthropod Response to Odorants

    OpenAIRE

    Stelinski, Lukasz; Tiwari, Siddharth

    2013-01-01

    Given the economic importance of insects and arachnids as pests of agricultural crops, urban environments or as vectors of plant and human diseases, various technologies are being developed as control tools. A subset of these tools focuses on modifying the behavior of arthropods by attraction or repulsion. Therefore, arthropods are often the focus of behavioral investigations. Various tools have been developed to measure arthropod behavior, including wind tunnels, flight mills, servospheres, ...

  4. 42 CFR 71.54 - Etiological agents, hosts, and vectors.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Etiological agents, hosts, and vectors. 71.54..., INSPECTION, LICENSING FOREIGN QUARANTINE Importations § 71.54 Etiological agents, hosts, and vectors. (a) A... any arthropod or other animal host or vector of human disease, or any exotic living arthropod or...

  5. Arthropods of the great indoors: characterizing diversity inside urban and suburban homes.

    Science.gov (United States)

    Bertone, Matthew A; Leong, Misha; Bayless, Keith M; Malow, Tara L F; Dunn, Robert R; Trautwein, Michelle D

    2016-01-01

    Although humans and arthropods have been living and evolving together for all of our history, we know very little about the arthropods we share our homes with apart from major pest groups. Here we surveyed, for the first time, the complete arthropod fauna of the indoor biome in 50 houses (located in and around Raleigh, North Carolina, USA). We discovered high diversity, with a conservative estimate range of 32-211 morphospecies, and 24-128 distinct arthropod families per house. The majority of this indoor diversity (73%) was made up of true flies (Diptera), spiders (Araneae), beetles (Coleoptera), and wasps and kin (Hymenoptera, especially ants: Formicidae). Much of the arthropod diversity within houses did not consist of synanthropic species, but instead included arthropods that were filtered from the surrounding landscape. As such, common pest species were found less frequently than benign species. Some of the most frequently found arthropods in houses, such as gall midges (Cecidomyiidae) and book lice (Liposcelididae), are unfamiliar to the general public despite their ubiquity. These findings present a new understanding of the diversity, prevalence, and distribution of the arthropods in our daily lives. Considering their impact as household pests, disease vectors, generators of allergens, and facilitators of the indoor microbiome, advancing our knowledge of the ecology and evolution of arthropods in homes has major economic and human health implications.

  6. Arthropods of the great indoors: characterizing diversity inside urban and suburban homes.

    Science.gov (United States)

    Bertone, Matthew A; Leong, Misha; Bayless, Keith M; Malow, Tara L F; Dunn, Robert R; Trautwein, Michelle D

    2016-01-01

    Although humans and arthropods have been living and evolving together for all of our history, we know very little about the arthropods we share our homes with apart from major pest groups. Here we surveyed, for the first time, the complete arthropod fauna of the indoor biome in 50 houses (located in and around Raleigh, North Carolina, USA). We discovered high diversity, with a conservative estimate range of 32-211 morphospecies, and 24-128 distinct arthropod families per house. The majority of this indoor diversity (73%) was made up of true flies (Diptera), spiders (Araneae), beetles (Coleoptera), and wasps and kin (Hymenoptera, especially ants: Formicidae). Much of the arthropod diversity within houses did not consist of synanthropic species, but instead included arthropods that were filtered from the surrounding landscape. As such, common pest species were found less frequently than benign species. Some of the most frequently found arthropods in houses, such as gall midges (Cecidomyiidae) and book lice (Liposcelididae), are unfamiliar to the general public despite their ubiquity. These findings present a new understanding of the diversity, prevalence, and distribution of the arthropods in our daily lives. Considering their impact as household pests, disease vectors, generators of allergens, and facilitators of the indoor microbiome, advancing our knowledge of the ecology and evolution of arthropods in homes has major economic and human health implications. PMID:26819844

  7. Genetic manipulation of endosymbionts to control vector and vector borne diseases

    Directory of Open Access Journals (Sweden)

    Jay Prakash Gupta

    Full Text Available Vector borne diseases (VBD are on the rise because of failure of the existing methods of control of vector and vector borne diseases and the climate change. A steep rise of VBDs are due to several factors like selection of insecticide resistant vector population, drug resistant parasite population and lack of effective vaccines against the VBDs. Environmental pollution, public health hazard and insecticide resistant vector population indicate that the insecticides are no longer a sustainable control method of vector and vector-borne diseases. Amongst the various alternative control strategies, symbiont based approach utilizing endosymbionts of arthropod vectors could be explored to control the vector and vector borne diseases. The endosymbiont population of arthropod vectors could be exploited in different ways viz., as a chemotherapeutic target, vaccine target for the control of vectors. Expression of molecules with antiparasitic activity by genetically transformed symbiotic bacteria of disease-transmitting arthropods may serve as a powerful approach to control certain arthropod-borne diseases. Genetic transformation of symbiotic bacteria of the arthropod vector to alter the vector’s ability to transmit pathogen is an alternative means of blocking the transmission of VBDs. In Indian scenario, where dengue, chikungunya, malaria and filariosis are prevalent, paratransgenic based approach can be used effectively. [Vet World 2012; 5(9.000: 571-576

  8. Arthropod-Borne Diseases: The Camper's Uninvited Guests.

    Science.gov (United States)

    Juckett, Gregory

    2015-08-01

    Arthropod-borne diseases are a major problem whenever outdoor activities bring arthropods and people into contact. The arthropods discussed here include arachnids (ticks) and insects. Most arthropod bites and stings are minor, with the notable exception being bee-sting anaphylaxis. Ticks cause the most disease transmission. Key hard tick vectors include black-legged (Ixodes), dog (Dermacentor), and lone star (Amblyomma) ticks, which transmit Lyme and various rickettsial diseases. Insect repellents, permethrin sprays, and proper tick inspection reduce this risk significantly. Lyme disease and the milder southern-tick-associated rash illness (STARI) are characterized by the erythema migrans rash followed, in the case of Lyme disease, by early, disseminated, and late systemic symptoms. Treatment is with doxycycline or ceftriaxone. Indefinite treatment of "chronic Lyme disease" based on subjective symptoms is not beneficial. Rickettsial diseases include ehrlichiosis, anaplasmosis, and Rocky Mountain spotted fever, which are characterized by fever, headache, and possible rash and should be empirically treated with doxycycline while awaiting laboratory confirmation. Tularemia is a bacterial disease (Francisella) spread by ticks and rabbits and characterized by fever and adenopathy. Treatment is with gentamicin or streptomycin. Babesiosis is a protozoal disease, mimicking malaria, that causes a self-limited flu-like disease in healthy hosts but can be life threatening with immune compromise. Treatment is with atovaquone and azithromycin. Other tick-related conditions include viral diseases (Powassan, Colorado tick fever, heartland virus), tick-borne relapsing fever (Borrelia), and tick paralysis (toxin). Mosquitoes, lice, fleas, and mites are notable for their annoying bites but are increasingly significant disease vectors even in the United States.

  9. Epidemiology and control of malaria and other arthropod born diseases

    Directory of Open Access Journals (Sweden)

    F. J. López-Antuñano

    1992-01-01

    Full Text Available Malaria and other arthropod born diseases remain a serious public health problem affecting the lives and health of certain social groups when the two basic strategies to control fail due to : (1 the lack of effective chemoprophylaxis/chemotherapy or the rapid development of drug resistance of the infectious agents and (2 the ineffectiveness of pesticides or the arthropod vectors develop resistance to them. These situations enhances the need for the design and implementation of other alternatives for sustainable health programmes. The application of the epidemiological methods is essential not only for analyzing the relevant data for the understanding of the biological characteristics of the infectious agents, their reservoirs and vectors and the methods for their control, but also for the assessment of the human behaviour, the environmental, social and economic factors involved in disease transmission and the capacity of the health systems to implement interventions for both changes in human behaviour and environmental management to purpose guaranteed prevention and control of malaria and other arthropod born diseases with efficiency, efficacy and equity. This paper discuss the evolution of the malaria arthropod diseases programmes in the American Region and the perspectives for their integration into health promotion programs and emphasis is made in the need to establish solid basis in the decision-making process for the selection of intervention strategies to remove the risk factors determining the probability to get sick or die from ABDs. The implications of the general planning and the polices to be adopted in an area should be analyzed in the light of programme feasibility at the local level, in the multisectoral context specific social groups and taking in consideration the principles of stratification and equity

  10. Quantitative phase imaging of arthropods

    Science.gov (United States)

    Sridharan, Shamira; Katz, Aron; Soto-Adames, Felipe; Popescu, Gabriel

    2015-01-01

    Abstract. Classification of arthropods is performed by characterization of fine features such as setae and cuticles. An unstained whole arthropod specimen mounted on a slide can be preserved for many decades, but is difficult to study since current methods require sample manipulation or tedious image processing. Spatial light interference microscopy (SLIM) is a quantitative phase imaging (QPI) technique that is an add-on module to a commercial phase contrast microscope. We use SLIM to image a whole organism springtail Ceratophysella denticulata mounted on a slide. This is the first time, to our knowledge, that an entire organism has been imaged using QPI. We also demonstrate the ability of SLIM to image fine structures in addition to providing quantitative data that cannot be obtained by traditional bright field microscopy. PMID:26334858

  11. Quantitative phase imaging of arthropods

    Science.gov (United States)

    Sridharan, Shamira; Katz, Aron; Soto-Adames, Felipe; Popescu, Gabriel

    2015-11-01

    Classification of arthropods is performed by characterization of fine features such as setae and cuticles. An unstained whole arthropod specimen mounted on a slide can be preserved for many decades, but is difficult to study since current methods require sample manipulation or tedious image processing. Spatial light interference microscopy (SLIM) is a quantitative phase imaging (QPI) technique that is an add-on module to a commercial phase contrast microscope. We use SLIM to image a whole organism springtail Ceratophysella denticulata mounted on a slide. This is the first time, to our knowledge, that an entire organism has been imaged using QPI. We also demonstrate the ability of SLIM to image fine structures in addition to providing quantitative data that cannot be obtained by traditional bright field microscopy.

  12. Factors Influencing Arthropod Diversity on Green Roofs

    Directory of Open Access Journals (Sweden)

    Bracha Y. Schindler

    2011-01-01

    Full Text Available Green roofs have potential for providing substantial habitat to plants, birds, and arthropod species that are not well supported by other urban habitats. Whereas the plants on a typical green roof are chosen and planted by people, the arthropods that colonize it can serve as an indicator of the ability of this novel habitat to support a diverse community of organisms. The goal of this observational study was to determine which physical characteristics of a roof or characteristics of its vegetation correlate with arthropod diversity on the roof. We intensively sampled the number of insect families on one roof with pitfall traps and also measured the soil arthropod species richness on six green roofs in the Boston, MA area. We found that the number of arthropod species in soil, and arthropod families in pitfall traps, was positively correlated with living vegetation cover. The number of arthropod species was not significantly correlated with plant diversity, green roof size, distance from the ground, or distance to the nearest vegetated habitat from the roof. Our results suggest that vegetation cover may be more important than vegetation diversity for roof arthropod diversity, at least for the first few years after establishment. Additionally, we found that even green roofs that are small and isolated can support a community of arthropods that include important functional groups of the soil food web.

  13. Knowledge of Arthropod Carnivory and Herbivory: Factors Influencing Preservice Elementary Teacher's Attitudes and Beliefs toward Arthropods

    Science.gov (United States)

    Wagler, Ron; Wagler, Amy

    2013-01-01

    Human negativity toward arthropods has been well documented but the factors that contribute to this negativity have been elusive. This study explored knowledge of arthropod carnivory and herbivory as possible casual factors that contribute to the negative tendencies preservice elementary teachers have toward most arthropods. Specifically, this…

  14. Expanding Integrated Vector Management to promote healthy environments.

    Science.gov (United States)

    Lizzi, Karina M; Qualls, Whitney A; Brown, Scott C; Beier, John C

    2014-08-01

    Integrated Vector Management (IVM) strategies are intended to protect communities from pathogen transmission by arthropods. These strategies target multiple vectors and different ecological and socioeconomic settings, but the aggregate benefits of IVM are limited by the narrow focus of its approach; IVM strategies aim only to control arthropod vectors. We argue that IVM should encompass environmental modifications at early stages - for instance, infrastructural development and sanitation services - to regulate not only vectors but also nuisance biting arthropods. An additional focus on nuisance biting arthropods will improve public health and quality of life and minimize social-disparity issues fostered by pests. Optimally, IVM could incorporate environmental awareness and promotion of control methods proactively to reduce threats of serious pest situations.

  15. Arthropod Diversity in a Tropical Forest

    DEFF Research Database (Denmark)

    Basset, Yves; Cizek, Lukas; Cuénoud, Philippe;

    2012-01-01

    Most eukaryotic organisms are arthropods. Yet, their diversity in rich terrestrial ecosystems is still unknown. Here we produce tangible estimates of the total species richness of arthropods in a tropical rainforest. Using a comprehensive range of structured protocols, we sampled the phylogenetic...

  16. Noninsect Arthropods in Popular Music

    Directory of Open Access Journals (Sweden)

    Joseph R. Coelho

    2011-05-01

    Full Text Available The occurrence of noninsect arthropods in popular music was examined in order to explore human attitudes toward these species, especially as compared to insects. Crustaceans were the most commonly referenced taxonomic group in artist names, album titles and cover art, followed by spiders and scorpions. The surprising prevalence of crustaceans may be related to the palatability of many of the species. Spiders and scorpions were primarily used for shock value, as well as totemic qualities of strength and ferocity. Spiders were the most abundant group among song titles, perhaps because of their familiarity to the general public. Three noninsect arthropod album titles were found from the early 1970s, then none appear until 1990. Older albums are difficult to find unless they are quite popular, and the resurgence of albums coincides with the rise of the internet. After 1990, issuance of such albums increased approximately linearly. Giant and chimeric album covers were the most common of themes, indicating the use of these animals to inspire fear and surprise. The lyrics of select songs are presented to illustrate the diversity of sentiments present, from camp spookiness to edibility.

  17. Environmental statistical modelling of mosquito vectors at different geographical scales

    NARCIS (Netherlands)

    Cianci, D.

    2015-01-01

    Vector-borne diseases are infections transmitted by the bite of infected arthropod vectors, such as mosquitoes, ticks, fleas, midges and flies. Vector-borne diseases pose an increasingly wider threat to global public health, both in terms of people affected and their geographical spread. Mosquitoes

  18. Tyrosine Detoxification Is an Essential Trait in the Life History of Blood-Feeding Arthropods.

    Science.gov (United States)

    Sterkel, Marcos; Perdomo, Hugo D; Guizzo, Melina G; Barletta, Ana Beatriz F; Nunes, Rodrigo D; Dias, Felipe A; Sorgine, Marcos H F; Oliveira, Pedro L

    2016-08-22

    Blood-feeding arthropods are vectors of infectious diseases such as dengue, Zika, Chagas disease, and malaria [1], and vector control is essential to limiting disease spread. Because these arthropods ingest very large amounts of blood, a protein-rich meal, huge amounts of amino acids are produced during digestion. Previous work on Rhodnius prolixus, a vector of Chagas disease, showed that, among all amino acids, only tyrosine degradation enzymes were overexpressed in the midgut compared to other tissues [2]. Here we demonstrate that tyrosine detoxification is an essential trait in the life history of blood-sucking arthropods. We found that silencing Rhodnius tyrosine aminotransferase (TAT) and 4-hydroxyphenylpyruvate dioxygenase (HPPD), the first two enzymes of the phenylalanine/tyrosine degradation pathway, caused the death of insects after a blood meal. This was confirmed by using the HPPD inhibitor mesotrione, which selectively killed hematophagous arthropods but did not affect non-hematophagous insects. In addition, mosquitoes and kissing bugs died after feeding on mice that had previously received a therapeutic effective oral dose (1 mg/kg) of nitisinone, another HPPD inhibitor used in humans for the treatment of tyrosinemia type I [3]. These findings indicate that HPPD (and TAT) can be a target for the selective control of blood-sucking disease vector populations. Because HPPD inhibitors are extensively used as herbicides and in medicine, these compounds may provide an alternative less toxic to humans and more environmentally friendly than the conventional neurotoxic insecticides that are currently used, with the ability to affect only hematophagous arthropods. PMID:27476595

  19. Effects of invasive plants on arthropods.

    Science.gov (United States)

    Litt, Andrea R; Cord, Erin E; Fulbright, Timothy E; Schuster, Greta L

    2014-12-01

    Non-native plants have invaded nearly all ecosystems and represent a major component of global ecological change. Plant invasions frequently change the composition and structure of vegetation communities, which can alter animal communities and ecosystem processes. We reviewed 87 articles published in the peer-reviewed literature to evaluate responses of arthropod communities and functional groups to non-native invasive plants. Total abundance of arthropods decreased in 62% of studies and increased in 15%. Taxonomic richness decreased in 48% of studies and increased in 13%. Herbivorous arthropods decreased in response to plant invasions in 48% of studies and increased in 17%, likely due to direct effects of decreased plant diversity. Predaceous arthropods decreased in response to invasive plants in 44% of studies, which may reflect indirect effects due to reductions in prey. Twenty-two percent of studies documented increases in predators, which may reflect changes in vegetation structure that improved mobility, survival, or web-building for these species. Detritivores increased in 67% of studies, likely in response to increased litter and decaying vegetation; no studies documented decreased abundance in this functional group. Although many researchers have examined effects of plant invasions on arthropods, sizeable information gaps remain, specifically regarding how invasive plants influence habitat and dietary requirements. Beyond this, the ability to predict changes in arthropod populations and communities associated with plant invasions could be improved by adopting a more functional and mechanistic approach. Understanding responses of arthropods to invasive plants will critically inform conservation of virtually all biodiversity and ecological processes because so many organisms depend on arthropods as prey or for their functional roles, including pollination, seed dispersal, and decomposition. Given their short generation times and ability to respond rapidly to

  20. Haematophagous arthropod saliva and host defense system: a tale of tear and blood

    Directory of Open Access Journals (Sweden)

    Andrade Bruno B.

    2005-01-01

    Full Text Available The saliva from blood-feeding arthropod vectors is enriched with molecules that display diverse functions that mediate a successful blood meal. They function not only as weapons against host's haemostatic, inflammatory and immune responses but also as important tools to pathogen establishment. Parasites, virus and bacteria taking advantage of vectors' armament have adapted to facilitate their entry in the host. Today, many salivary molecules have been identified and characterized as new targets to the development of future vaccines. Here we focus on current information on vector's saliva and the molecules responsible to modify host's hemostasis and immune response, also regarding their role in disease transmission.

  1. Arthropods (http://www.iaees.org/publications/journals/arthropods/online-version.asp

    Directory of Open Access Journals (Sweden)

    arthropods@iaees.org

    Full Text Available Arthropods ISSN 2224-4255 URL: http://www.iaees.org/publications/journals/arthropods/online-version.asp RSS: http://www.iaees.org/publications/journals/arthropods/rss.xml E-mail: arthropods@iaees.org Editor-in-Chief: WenJun Zhang Aims and Scope ARTHROPODS (ISSN 2224-4255 is an international journal devoted to the publication of articles on various aspects of arthropods, e.g., ecology, biogeography, systematics, biodiversity (species diversity, genetic diversity, et al., conservation, control, etc. The journal provides a forum for examining the importance of arthropods in biosphere (both terrestrial and marine ecosystems and human life in such fields as agriculture, forestry, fishery, environmental management and human health. The scope of Arthropods is wide and embraces all arthropods-insects, arachnids, crustaceans, centipedes, millipedes, and other arthropods. Articles/short communications on new taxa (species, genus, families, orders, etc. and new records of arthropods are particularly welcome. Authors can submit their works to the email box of this journal, arthropods@iaees.org. All manuscripts submitted to this journal must be previously unpublished and may not be considered for publication elsewhere at any time during review period of this journal. Authors are asked to read Author Guidelines before submitting manuscripts. In addition to free submissions from authors around the world, special issues are also accepted. The organizer of a special issue can collect submissions (yielded from a research project, a research group, etc. on a specific research topic, or submissions of a scientific conference for publication of special issue.

  2. The ecological foundations of transmission potential and vector-borne disease in urban landscapes

    OpenAIRE

    Shannon L LaDeau; Allan, Brian F.; Leisnham, Paul T.; Michael Z Levy

    2015-01-01

    Urban transmission of arthropod-vectored disease has increased in recent decades. Understanding and managing transmission potential in urban landscapes requires integration of sociological and ecological processes that regulate vector population dynamics, feeding behavior, and vector-pathogen interactions in these unique ecosystems. Vectorial capacity is a key metric for generating predictive understanding about transmission potential in systems with obligate vector transmission. This review ...

  3. Effects of Climate and Climate Change on Vectors and Vector-Borne Diseases: Ticks Are Different.

    Science.gov (United States)

    Ogden, Nick H; Lindsay, L Robbin

    2016-08-01

    There has been considerable debate as to whether global risk from vector-borne diseases will be impacted by climate change. This has focussed on important mosquito-borne diseases that are transmitted by the vectors from infected to uninfected humans. However, this debate has mostly ignored the biological diversity of vectors and vector-borne diseases. Here, we review how climate and climate change may impact those most divergent of arthropod disease vector groups: multivoltine insects and hard-bodied (ixodid) ticks. We contrast features of the life cycles and behaviour of these arthropods, and how weather, climate, and climate change may have very different impacts on the spatiotemporal occurrence and abundance of vectors, and the pathogens they transmit.

  4. Effects of Climate and Climate Change on Vectors and Vector-Borne Diseases: Ticks Are Different.

    Science.gov (United States)

    Ogden, Nick H; Lindsay, L Robbin

    2016-08-01

    There has been considerable debate as to whether global risk from vector-borne diseases will be impacted by climate change. This has focussed on important mosquito-borne diseases that are transmitted by the vectors from infected to uninfected humans. However, this debate has mostly ignored the biological diversity of vectors and vector-borne diseases. Here, we review how climate and climate change may impact those most divergent of arthropod disease vector groups: multivoltine insects and hard-bodied (ixodid) ticks. We contrast features of the life cycles and behaviour of these arthropods, and how weather, climate, and climate change may have very different impacts on the spatiotemporal occurrence and abundance of vectors, and the pathogens they transmit. PMID:27260548

  5. Factors Influencing Arthropod Diversity on Green Roofs

    OpenAIRE

    Bracha Y. Schindler; Alden B. Griffith; Kristina N. Jones

    2011-01-01

    Green roofs have potential for providing substantial habitat to plants, birds, and arthropod species that are not well supported by other urban habitats. Whereas the plants on a typical green roof are chosen and planted by people, the arthropods that colonize it can serve as an indicator of the ability of this novel habitat to support a diverse community of organisms. The goal of this observational study was to determine which physical characteristics of a roof or characteristics of its veget...

  6. [Climate change influences the incidence of arthropod-borne diseases in the Netherlands].

    Science.gov (United States)

    Rahamat-Langendoen, J C; van Vliet, J A; Reusken, C B E M

    2008-04-12

    Climate change is associated with changes in the occurrence of arthropod-borne diseases. It is difficult to foresee which arthropod-borne diseases will appear in the Netherlands due to climate change. Climate change influences the prevalence of ticks and may lead to a further increase in Lyme disease and an increased risk of the introduction of rickettsioses. With further warming of the climate there is a real possibility of settlement of the mosquito Aedes albopictus and introduction of the sandfly in the Netherlands. Whether this will lead to circulation of micro-organisms transmitted by these vectors (e.g. West Nile virus, Dengue virus, Leishmania) is not clear. Continued vigilance is necessary, even for vector-borne diseases that appear to be less relevant for the Netherlands.

  7. Feeding and the rhodopsin family G-Protein Coupled Receptors (GPCRs in nematodes and arthropods

    Directory of Open Access Journals (Sweden)

    Joao Carlos dos Reis Cardoso

    2012-12-01

    Full Text Available In vertebrates, receptors of the rhodopsin G-protein coupled superfamily (GPCRs play an important role in the regulation of feeding and energy homeostasis and are activated by peptide hormones produced in the brain-gut axis. These peptides regulate appetite and energy expenditure by promoting or inhibiting food intake. Sequence and function homologues of human GPCRs involved in feeding exist in the nematode roundworm, Caenorhabditis elegans (C. elegans and the arthropod fruit fly, Drosophila melanogaster (D. melanogaster, suggesting that the mechanisms that regulate food intake emerged early and have been conserved during metazoan radiation. Nematodes and arthropods are the most diverse and successful animal phyla on Earth. They can survive in a vast diversity of environments and have acquired distinct life styles and feeding strategies. The aim of the present review is to investigate if this diversity has affected the evolution of invertebrate GPCRs. Homologues of the C. elegans and D. melanogaster rhodopsin receptors were characterized in the genome of other nematodes and arthropods and receptor evolution compared. With the exception of bombesin receptors (BBR that are absent from nematodes, a similar gene complement was found. In arthropods, rhodopsin GPCR evolution is characterized by species-specific gene duplications and deletions and in nematodes by gene expansions in species with a free-living stage and gene deletions in representatives of obligate parasitic taxa. Based upon variation in GPCR gene number and potentially divergent functions within phyla we hypothesize that life style and feeding diversity practiced by nematodes and arthropods was one factor that contributed to rhodopsin GPCR gene evolution. Understanding how the regulation of food intake has evolved in invertebrates will contribute to the development of novel drugs to control nematodes and arthropods and the pests and diseases that use them as vectors.

  8. Feeding and the rhodopsin family g-protein coupled receptors in nematodes and arthropods.

    Science.gov (United States)

    Cardoso, João C R; Félix, Rute C; Fonseca, Vera G; Power, Deborah M

    2012-01-01

    In vertebrates, receptors of the rhodopsin G-protein coupled superfamily (GPCRs) play an important role in the regulation of feeding and energy homeostasis and are activated by peptide hormones produced in the brain-gut axis. These peptides regulate appetite and energy expenditure by promoting or inhibiting food intake. Sequence and function homologs of human GPCRs involved in feeding exist in the nematode roundworm, Caenorhabditis elegans (C. elegans), and the arthropod fruit fly, Drosophila melanogaster (D. melanogaster), suggesting that the mechanisms that regulate food intake emerged early and have been conserved during metazoan radiation. Nematodes and arthropods are the most diverse and successful animal phyla on Earth. They can survive in a vast diversity of environments and have acquired distinct life styles and feeding strategies. The aim of the present review is to investigate if this diversity has affected the evolution of invertebrate GPCRs. Homologs of the C. elegans and D. melanogaster rhodopsin receptors were characterized in the genome of other nematodes and arthropods and receptor evolution compared. With the exception of bombesin receptors (BBR) that are absent from nematodes, a similar gene complement was found. In arthropods, rhodopsin GPCR evolution is characterized by species-specific gene duplications and deletions and in nematodes by gene expansions in species with a free-living stage and gene deletions in representatives of obligate parasitic taxa. Based upon variation in GPCR gene number and potentially divergent functions within phyla we hypothesize that life style and feeding diversity practiced by nematodes and arthropods was one factor that contributed to rhodopsin GPCR gene evolution. Understanding how the regulation of food intake has evolved in invertebrates will contribute to the development of novel drugs to control nematodes and arthropods and the pests and diseases that use them as vectors. PMID:23264768

  9. Simulation of arthropod abundance from plant composition

    Directory of Open Access Journals (Sweden)

    WenJun Zhang

    2011-04-01

    Full Text Available The relationship between arthropod abundance and plant composition is extremely complex. It is very hard to develop a mechanistic model to describe the relationship. This study aimed to simulate arthropod abundance from plant composition on grassland using an artificial neural network developed by the author, and to compare simulation performances between the neural network and conventional models. The results revealed that there were complex interactions between plants and arthropods, and the arthropod abundance on grassland was significantly determined of plant families and their cover-degrees rather than plant species and their cover-degrees. Neural network exhibited a better simulation performance than multivariate regression and response surface model. Cross validation indicated that prediction performance of neural network was also superior to these models. It was concluded that neural network is an effective tool to model arthropod abundance from plant composition on grassland. A moderate dimensionality for input space may be determined to produce a reasonably trained neural network. Such procedures for dimensionality reduction as PCE, etc., were suggested being used in the data treatment in neural network modeling. A high dimensionality for input space and a few samples in the input set would result in the deficient learning of neural network. Randomization procedure for sample submission would help to eliminate the sequence correlation but may result in a worse performance in simulation and prediction. It was suggested that randomization procedure could be used to the sample submission for these situations with a lot of samples and a lower dimensionality.

  10. Sophisticated digestive systems in early arthropods.

    Science.gov (United States)

    Vannier, Jean; Liu, Jianni; Lerosey-Aubril, Rudy; Vinther, Jakob; Daley, Allison C

    2014-01-01

    Understanding the way in which animals diversified and radiated during their early evolutionary history remains one of the most captivating of scientific challenges. Integral to this is the 'Cambrian explosion', which records the rapid emergence of most animal phyla, and for which the triggering and accelerating factors, whether environmental or biological, are still unclear. Here we describe exceptionally well-preserved complex digestive organs in early arthropods from the early Cambrian of China and Greenland with functional similarities to certain modern crustaceans and trace these structures through the early evolutionary lineage of fossil arthropods. These digestive structures are assumed to have allowed for more efficient digestion and metabolism, promoting carnivory and macrophagy in early arthropods via predation or scavenging. This key innovation may have been of critical importance in the radiation and ecological success of Arthropoda, which has been the most diverse and abundant invertebrate phylum since the Cambrian. PMID:24785191

  11. Responses of prairie arthropod communities to fire and fertilizer: Balancing plant and arthropod conservation

    Science.gov (United States)

    Hartley, M.K.; Rogers, W.E.; Siemann, E.; Grace, J.

    2007-01-01

    Fire is an important tool for limiting woody plant invasions into prairies, but using fire management to maintain grassland plant communities may inadvertently reduce arthropod diversity. To test this, we established twenty-four 100 m2 plots in a tallgrass prairie in Galveston County, Texas, in spring 2000. Plots were assigned a fire (no burn, one time burn [2000], two time burn [2000, 2001]) and fertilization treatment (none, NPK addition) in a full factorial design. Fertilization treatments allowed us to examine the effects of fire at a different level of productivity. We measured plant cover by species and sampled arthropods with sweep nets during the 2001 growing season. Path analysis indicated that fertilization reduced while annual fires increased arthropod diversity via increases and decreases in woody plant abundance, respectively. There was no direct effect of fire on arthropod diversity or abundance. Diptera and Homoptera exhibited particularly strong positive responses to fires. Lepidoptera had a negative response to nutrient enrichment. Overall, the negative effects of fire on the arthropod community were minor in contrast to the strong positive indirect effects of small-scale burning on arthropod diversity if conservation of particular taxa is not a priority. The same fire regime that minimized woody plant invasion also maximized arthropod diversity.

  12. Pacific Remote Islands MNM: Initial Survey Instructions for Terrestrial Arthropods

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purposes of the terrestrial arthropod surveys are to: develop a species list of native and non-native terrestrial arthropods on land portions of the refuge;...

  13. Collective behavior in an early Cambrian arthropod.

    Science.gov (United States)

    Hou, Xian-Guang; Siveter, Derek J; Aldridge, Richard J; Siveter, David J

    2008-10-10

    Examples that indicate collective behavior in the fossil record are rare. A group association of specimens that belong to a previously unknown arthropod from the Chengjiang Lagerstätte, China, provides evidence that such behavior was present in the early Cambrian (about 525 million years ago), coincident with the earliest extensive diversification of the Metazoa, the so-called Cambrian explosion event. The chainlike form of these specimens is unique for any arthropod, fossil or living, and most likely represents behavior associated with migration. PMID:18845748

  14. Vertical T-maze choice assay for arthropod response to odorants.

    Science.gov (United States)

    Stelinski, Lukasz; Tiwari, Siddharth

    2013-01-01

    Given the economic importance of insects and arachnids as pests of agricultural crops, urban environments or as vectors of plant and human diseases, various technologies are being developed as control tools. A subset of these tools focuses on modifying the behavior of arthropods by attraction or repulsion. Therefore, arthropods are often the focus of behavioral investigations. Various tools have been developed to measure arthropod behavior, including wind tunnels, flight mills, servospheres, and various types of olfactometers. The purpose of these tools is to measure insect or arachnid response to visual or more often olfactory cues. The vertical T-maze olfactometer described here measures choices performed by insects in response to attractants or repellents. It is a high throughput assay device that takes advantage of the positive phototaxis (attraction to light) and negative geotaxis (tendency to walk or fly upward) exhibited by many arthropods. The olfactometer consists of a 30 cm glass tube that is divided in half with a Teflon strip forming a T-maze. Each half serves as an arm of the olfactometer enabling the test subjects to make a choice between two potential odor fields in assays involving attractants. In assays involving repellents, lack of normal response to known attractants can also be measured as a third variable. PMID:23439130

  15. Arthropod pattern theory and Cambrian trilobites

    NARCIS (Netherlands)

    Sundberg, Frederick A.

    1995-01-01

    An analysis of duplomere (= segment) distribution within the cephalon, thorax, and pygidium of Cambrian trilobites was undertaken to determine if the Arthropod Pattern Theory (APT) proposed by Schram & Emerson (1991) applies to Cambrian trilobites. The boundary of the cephalon/thorax occurs within t

  16. Physical conditions affecting pyrethroid toxicity in arthropods.

    NARCIS (Netherlands)

    Jagers op Akkerhuis, G.A.J.M.

    1993-01-01

    The aim of this thesis was to obtain mechanistic information about how the toxicity of pesticides in the field is affected by physical factors, pesticide bioavailability and arthropod behaviour. The pyrethroid insecticide deltamethrin and linyphiid spiders were selected as pesticide-effect model. In

  17. Arthropod-borne infections in travelled dogs in Europe

    Directory of Open Access Journals (Sweden)

    Hamel Dietmar

    2013-01-01

    Full Text Available Pet animal movement is ever increasing within the European Union and in that context canine vectorborne infections gained a considerable importance. Information on these infections in travelled dogs is nevertheless limited. A first prospective study on vector-borne infections was conducted in 106 dogs travelling from Germany to countries in South and South-East Europe. The dogs were screened prior to and consecutively up to three times after travel by haematological (Giemsa-stained buffy coat smears, Knott’s-Test, molecular biological (PCR as well as serological (IFAT, DiroChek®-ELISA methods for arthropod-borne infections. Seven animals were seropositive for antibodies against Babesia canis sspp., Leishmania spp. and/or Ehrlichia canis prior to travel to Italy, Spain, France, Croatia, Greece, or Hungary. In the consecutive screening after return there was no increase in the number of seropositive dogs. None was positive in direct methods. The mean duration of the stay was 17 days and 51% of the dogs were prophylactically treated with ectoparasiticidal formulations. Preliminary data from this study on canine vector-borne infections indicate a low risk for infection during a limited single stay in endemic countries.

  18. Vector-borne diseases.

    Science.gov (United States)

    Gubler, D J

    2009-08-01

    Vector-borne diseases have been the scourge of man and animals since the beginning of time. Historically, these are the diseases that caused the great plagues such as the 'Black Death' in Europe in the 14th Century and the epidemics of yellow fever that plagued the development of the New World. Others, such as Nagana, contributed to the lack of development in Africa for many years. At the turn of the 20th Century, vector-borne diseases were among the most serious public and animal health problems in the world. For the most part, these diseases were controlled by the middle of the 20th Century through the application of knowledge about their natural history along with the judicious use of DDT (dichlorodiphenyltrichloroethane) and other residual insecticides to interrupt the transmission cycle between arthropod and vertebrate host. However, this success initiated a period of complacency in the 1960s and 1970s, which resulted in the redirection of resources away from prevention and control of vector-borne diseases. The 1970s was also a time in which there were major changes to public health policy. Global trends, combined with changes in animal husbandry, urbanisation, modern transportation and globalisation, have resulted in a global re-emergence of epidemic vector-borne diseases affecting both humans and animals over the past 30 years. PMID:20128467

  19. Folsomia candida (Collembola): a "standard" soil arthropod.

    Science.gov (United States)

    Fountain, Michelle T; Hopkin, Steve P

    2005-01-01

    Folsomia candida Willem 1902, a member of the order Collembola (colloquially called springtails), is a common and widespread arthropod that occurs in soils throughout the world. The species is parthenogenetic and is easy to maintain in the laboratory on a diet of granulated dry yeast. F. candida has been used as a "standard" test organism for more than 40 years for estimating the effects of pesticides and environmental pollutants on nontarget soil arthropods. However, it has also been employed as a model for the investigation of numerous other phenomena such as cold tolerance, quality as a prey item, and effects of microarthropod grazing on pathogenic fungi and mycorrhizae of plant roots. In this comprehensive review, aspects of the life history, ecology, and ecotoxicology of F. candida are covered. We focus on the recent literature, especially studies that have examined the effects of soil pollutants on reproduction in F. candida using the protocol published by the International Standards Organization in 1999.

  20. Ecology of herbivorous arthropods in urban landscapes.

    Science.gov (United States)

    Raupp, Michael J; Shrewsbury, Paula M; Herms, Daniel A

    2010-01-01

    Urbanization affects communities of herbivorous arthropods and provides opportunities for dramatic changes in their abundance and richness. Underlying these changes are creation of impervious surfaces; variation in the density, diversity, and complexity of vegetation; and maintenance practices including pulsed inputs of fertilizers, water, and pesticides. A rich body of knowledge provides theoretical underpinnings for predicting and understanding impacts of urbanization on arthropods. However, relatively few studies have elucidated mechanisms that explain patterns of insect and mite abundance and diversity across urbanization gradients. Published accounts suggest that responses to urbanization are often taxon specific, highly variable, and linked to properties of urbanization that weaken top-down and/or bottom-up processes, thereby destabilizing populations of herbivores and their natural enemies. In addition to revealing patterns in diversity and abundance of herbivores across urbanization gradients, a primary objective of this review is to examine mechanisms underlying these patterns and to identify potential hypotheses for future testing.

  1. Role of Arthropods in Maintaining Soil Fertility

    Directory of Open Access Journals (Sweden)

    Thomas W. Culliney

    2013-09-01

    Full Text Available In terms of species richness, arthropods may represent as much as 85% of the soil fauna. They comprise a large proportion of the meso- and macrofauna of the soil. Within the litter/soil system, five groups are chiefly represented: Isopoda, Myriapoda, Insecta, Acari, and Collembola, the latter two being by far the most abundant and diverse. Arthropods function on two of the three broad levels of organization of the soil food web: they are plant litter transformers or ecosystem engineers. Litter transformers fragment, or comminute, and humidify ingested plant debris, which is deposited in feces for further decomposition by micro-organisms, and foster the growth and dispersal of microbial populations. Large quantities of annual litter input may be processed (e.g., up to 60% by termites. The comminuted plant matter in feces presents an increased surface area to attack by micro-organisms, which, through the process of mineralization, convert its organic nutrients into simpler, inorganic compounds available to plants. Ecosystem engineers alter soil structure, mineral and organic matter composition, and hydrology. The burrowing by arthropods, particularly the subterranean network of tunnels and galleries that comprise termite and ant nests, improves soil porosity to provide adequate aeration and water-holding capacity below ground, facilitate root penetration, and prevent surface crusting and erosion of topsoil. Also, the movement of particles from lower horizons to the surface by ants and termites aids in mixing the organic and mineral fractions of the soil. The feces of arthropods are the basis for the formation of soil aggregates and humus, which physically stabilize the soil and increase its capacity to store nutrients.

  2. Arthropod Surveillance Programs: Basic Components, Strategies, and Analysis

    OpenAIRE

    Cohnstaedt, Lee W.; Rochon, Kateryn; Duehl, Adrian J.; Anderson, John F.; Barrera, Roberto; Su, Nan-Yao; Gerry, Alec C.; Obenauer, Peter J.; Campbell, James F.; Lysyk, Tim J.; Allan, Sandra A.

    2012-01-01

    Effective entomological surveillance planning stresses a careful consideration of methodology, trapping technologies, and analysis techniques. Herein, the basic principles and technological components of arthropod surveillance plans are described, as promoted in the symposium “Advancements in arthropod monitoring technology, techniques, and analysis” presented at the 58th annual meeting of the Entomological Society of America in San Diego, CA. Interdisciplinary examples of arthropod monitorin...

  3. Environmental and economic impact of alien terrestrial arthropods in Europe

    OpenAIRE

    Sibylle Vaes-Petignat; Wolfgang Nentwig

    2014-01-01

    In the last few decades, the abundance and importance of invasive alien species have grown continuously due to the undiminished growth of global trade. In most cases, arthropod introductions were unintended and occurred as hitchhikers or contaminants. Alien arthropods can have significant environmental impacts and can be economically costly. To measure these impacts, we expand a generic impact scoring system initially developed for mammals and birds, and applied it to terrestrial arthropods. ...

  4. Behaviour of filariae: morphological and anatomical signatures of their life style within the arthropod and vertebrate hosts

    OpenAIRE

    Bain, Odile; Babayan, Simon

    2003-01-01

    This paper attempts to pinpoint the most original morphological anatomical features of the biology of filariae per se and those which are or could be important for triggering regulatory processes in the arthropod vector and uncontrolled pathogenic processes in the vertebrate hosts. The following stages are considered: the motile egg or newly-hatched larva, the microfilaria, in the lymphatic or blood vessels of its vertebrate host; the larva, its migrations and its intrasyncitial development i...

  5. Repeated Raking of Pine Plantations Alters Soil Arthropod Communities

    Directory of Open Access Journals (Sweden)

    Holly K. Ober

    2014-04-01

    Full Text Available Terrestrial arthropods in forests are engaged in vital ecosystem functions that ultimately help maintain soil productivity. Repeated disturbance can cause abrupt and irreversible changes in arthropod community composition and thereby alter trophic interactions among soil fauna. An increasingly popular means of generating income from pine plantations in the Southeastern U.S. is annual raking to collect pine litter. We raked litter once per year for three consecutive years in the pine plantations of three different species (loblolly, Pinus taeda; longleaf, P. palustris; and slash, P. elliottii. We sampled arthropods quarterly for three years in raked and un-raked pine stands to assess temporal shifts in abundance among dominant orders of arthropods. Effects varied greatly among orders of arthropods, among timber types, and among years. Distinct trends over time were apparent among orders that occupied both high trophic positions (predators and low trophic positions (fungivores, detritivores. Multivariate analyses demonstrated that raking caused stronger shifts in arthropod community composition in longleaf and loblolly than slash pine stands. Results highlight the role of pine litter in shaping terrestrial arthropod communities, and imply that repeated removal of pine straw during consecutive years is likely to have unintended consequences on arthropod communities that exacerbate over time.

  6. Arthropod Borne Diseases in Imposed War during 1980-88

    Directory of Open Access Journals (Sweden)

    M Khoobdel

    2008-06-01

    Full Text Available Background: Personnel of military forces have close contact with natural habitat and usually encounter with bite of arthropods and prone to be infected with arthropod borne diseases. The imposed war against Iran was one of the most important and the longest war in the Middle East and even in the world and military people faced various diseases. The aim of this study was to review prevalence of arthropod borne diseases and to collect relevant information and valuable experiences during the imposed war.Methods: The present survey is a historical research and cross-sectional study, focused on arthropod fauna, situation of different arthropod borne diseases and also the ways which military personnel used to protect themselves against them. The information was adopted from valid military health files and also interviewing people who participated in the war.Results: Scabies, cutaneous leishmaniasis, sandfly fever and pediculosis were more prevalent among other arthropod -borne diseases in Iran-Iraq war. Measures to control arthropods and diseases at wartime mainly included: scheduled spraying of pesticides, leishmanization and treatment of patients.Conclusion: Although measures used during the war to control arthropods were proper, however, due to needs and importance of military forces to new equipment and technologies, it is recommended to use deltamethrin-impreg­nated bed net, permethrin treated military uniforms and various insect repellents in future.

  7. Soil arthropods as test organisms for ecotoxicology

    Energy Technology Data Exchange (ETDEWEB)

    Iglisch, I.

    1981-02-01

    The importance of arthropods - organisms which usually grow in masses - for soil biology depends on their capacity to participate in the continuous transformation of organic substances within the relevant biocenosis and thus to take part in the maintenance of the ecological balance. In ecotoxicology, i.e. the science of substances having a detrimental effect on the natural balance of ecosystems, we try to find ways to evaluate risk of substances hazardous to the environment. In principle, biocenoses would offer themselves in their entirety as appropriate test objects for ecotoxicological evaluation of chemicals. Since it will not yet be possible in the near future to carry out this kind of studies, individual organisms proved as representatives of terrestial biotopes have to be chosen for these purposes. Primarily, Collembola, Coleoptera, and Diptera (larvae) are part of the meso- and macrofauna of soil arthropods or soil insects according to the experience made up to now in respect of their importance for soil biology. Representatives of such organisms should be used to develop test procedures to indicate damage even of a subacute, chronic nature or the impairment of their functional performance the maintance of which is a prerequisite for the ecological balance.

  8. Hematopoiesis and hematopoietic organs in arthropods.

    Science.gov (United States)

    Grigorian, Melina; Hartenstein, Volker

    2013-03-01

    Hemocytes (blood cells) are motile cells that move throughout the extracellular space and that exist in all clades of the animal kingdom. Hemocytes play an important role in shaping the extracellular environment and in the immune response. Developmentally, hemocytes are closely related to the epithelial cells lining the vascular system (endothelia) and the body cavity (mesothelia). In vertebrates and insects, common progenitors, called hemangioblasts, give rise to the endothelia and blood cells. In the adult animal, many differentiated hemocytes seem to retain the ability to proliferate; however, in most cases investigated closely, the bulk of hemocyte proliferation takes place in specialized hematopoietic organs. Hematopoietic organs provide an environment where undifferentiated blood stem cells are able to self-renew, and at the same time generate offspring that differentiate into different blood cell types. Hematopoiesis in vertebrates, taking place in the bone marrow, has been subject to intensive research by immunologists and stem cell biologists. Much less is known about blood cell formation in invertebrate animals. In this review, we will survey structural and functional properties of invertebrate hematopoietic organs, with a main focus on insects and other arthropod taxa. We will then discuss similarities, at the molecular and structural level, that are apparent when comparing the development of blood cells in hematopoietic organs of vertebrates and arthropods. Our comparative review is intended to elucidate aspects of the biology of blood stem cells that are more easily missed when focusing on one or a few model species. PMID:23319182

  9. A molecular palaeobiological exploration of arthropod terrestrialization

    Science.gov (United States)

    Carton, Robert; Edgecombe, Gregory D.

    2016-01-01

    Understanding animal terrestrialization, the process through which animals colonized the land, is crucial to clarify extant biodiversity and biological adaptation. Arthropoda (insects, spiders, centipedes and their allies) represent the largest majority of terrestrial biodiversity. Here we implemented a molecular palaeobiological approach, merging molecular and fossil evidence, to elucidate the deepest history of the terrestrial arthropods. We focused on the three independent, Palaeozoic arthropod terrestrialization events (those of Myriapoda, Hexapoda and Arachnida) and showed that a marine route to the colonization of land is the most likely scenario. Molecular clock analyses confirmed an origin for the three terrestrial lineages bracketed between the Cambrian and the Silurian. While molecular divergence times for Arachnida are consistent with the fossil record, Myriapoda are inferred to have colonized land earlier, substantially predating trace or body fossil evidence. An estimated origin of myriapods by the Early Cambrian precedes the appearance of embryophytes and perhaps even terrestrial fungi, raising the possibility that terrestrialization had independent origins in crown-group myriapod lineages, consistent with morphological arguments for convergence in tracheal systems. This article is part of the themed issue ‘Dating species divergences using rocks and clocks’. PMID:27325830

  10. Epidemic situation of arthropod-borne infectious diseases%虫媒传染病流行现状

    Institute of Scientific and Technical Information of China (English)

    李文刚; 赵敏

    2011-01-01

    Arthropod-borne infectious diseases have increasingly threatened human health, and they have approximately accounted for three fourth of emerging infectious diseases in recent years. Environmental change and natural disasters may exacerbate the prevalence of arthropod-borne infectious diseases. Controlling and eliminating insect vectors are important preventive measures. This review focuses on the category, epidemic trends, prevention and control measures of arthropod-borne infectious diseases and the prevalence of emerging arthropod-borne infectious diseases in China.%虫媒传染病对人类社会的危害性逐渐增加,近年新发的传染病有3/4属于虫媒传染病.环境改变和自然灾害可加剧虫媒传染病的流行,其防治重点为控制或消除传播媒介.本文就目前虫媒传染病的种类、流行趋势、防治及我国近年新发虫媒传染病情况做一阐述.

  11. The Insect Microbiome Modulates Vector Competence for Arboviruses

    OpenAIRE

    Natapong Jupatanakul; Shuzhen Sim; George Dimopoulos

    2014-01-01

    Diseases caused by arthropod-borne viruses (arboviruses), such as Dengue, West Nile, and Chikungunya, constitute a major global health burden and are increasing in incidence and geographic range. The natural microbiota of insect vectors influences various aspects of host biology, such as nutrition, reproduction, metabolism, and immunity, and recent studies have highlighted the ability of insect-associated bacteria to reduce vector competence for arboviruses and other pathogens. This reduction...

  12. Bartonellae in animals and vectors in New Caledonia

    OpenAIRE

    Mediannikov, Oleg; Davoust, B.; Cabre, O; Rolain, J. M.; Raoult, Didier

    2011-01-01

    Bartonellae are gram-negative facultative intracellular alpha-proteobacteria from the family Bartonellaceae. The natural history of bartonellae consists of a reservoir/host, which is a vertebrate with chronic intravascular infection with sustained bacteremia, and a vector (usually an arthropod) that transfers the bacteria from the reservoir to a susceptible yet uninfected host. In order to reveal the sources and reservoirs of Bartonella infection in animals and vectors in New Caledonia, we co...

  13. Environmental and economic impact of alien terrestrial arthropods in Europe

    Directory of Open Access Journals (Sweden)

    Sibylle Vaes-Petignat

    2014-06-01

    Full Text Available In the last decades abundance and importance of invasive alien species has grown continuously due to the undiminished growth of global trade. In most cases, arthropod introductions were unintended and occurred as hitchhikers or contaminants. Alien arthropods can have significant environmental impacts and can be economically costly. To measure these impacts, we expand the generic impact scoring system initially developed for mammals and birds, and applied it to terrestrial arthropods. The scoring of the 77 most widely distributed arthropod species alien to Europe revealed the mite Varroa destructor as the most harmful species, followed by the Chinese longhorn beetle Anoplophora chinensis and the Argentine ant Linepithema humile. The highest environmental impact is through herbivory, disease transmission, and ecosystem impacts. The highest economic impact is on agriculture and human infrastructure. The generic impact scoring system allows comparing impact scores of vertebrates and arthropods, thus serving as a background for decision making processes of policies and stakeholders.

  14. Vector analysis

    CERN Document Server

    Newell, Homer E

    2006-01-01

    When employed with skill and understanding, vector analysis can be a practical and powerful tool. This text develops the algebra and calculus of vectors in a manner useful to physicists and engineers. Numerous exercises (with answers) not only provide practice in manipulation but also help establish students' physical and geometric intuition in regard to vectors and vector concepts.Part I, the basic portion of the text, consists of a thorough treatment of vector algebra and the vector calculus. Part II presents the illustrative matter, demonstrating applications to kinematics, mechanics, and e

  15. About vectors

    CERN Document Server

    Hoffmann, Banesh

    1975-01-01

    From his unusual beginning in ""Defining a vector"" to his final comments on ""What then is a vector?"" author Banesh Hoffmann has written a book that is provocative and unconventional. In his emphasis on the unresolved issue of defining a vector, Hoffmann mixes pure and applied mathematics without using calculus. The result is a treatment that can serve as a supplement and corrective to textbooks, as well as collateral reading in all courses that deal with vectors. Major topics include vectors and the parallelogram law; algebraic notation and basic ideas; vector algebra; scalars and scalar p

  16. Arthropod borne diseases in Italy: from a neglected matter to an emerging health problem

    Directory of Open Access Journals (Sweden)

    Roberto Romi

    2010-12-01

    Full Text Available In medical entomology, "Arthropod Borne Diseases", or "Vector Borne Diseases" (VBD are intended as a group of human and animal infections caused by different pathogen organisms (protozoa, helminthes, bacteria and viruses transmitted by the bite of a bloodsucking insect or arachnid. It is commonly known that the infectious diseases transmitted by Arthropods are mainly affecting tropical and subtropical countries, nevertheless some of them were or are still common also in the northern hemisphere, where they are usually maintained under control. VBD still represent some of the most important public health problems in the endemic areas but are becoming source of concern for developed countries too. Since the last decades of the past century, a number of VBD has been spreading geographically, being recorded for the first time in areas outside their original range. This phenomenon is strictly related to the peculiar epidemiological characteristics of these diseases, that are considered the most susceptible to climatic, environmental and socioeconomic changes. This article is a short overview of the VBD endemic and emerging in Italy. The possibility that some exotic vectors and/or pathogens could be introduced and become established in Italy is also discussed.

  17. Evaluating potential risks of transgenic arthropods for pest management programmes

    International Nuclear Information System (INIS)

    Genetic modification using recombinant DNA methods can now be used, almost routinely, to transform pest and beneficial arthropods and such genetically engineered insects and mites could be used to improve pest management programs. Genetic manipulation with recombinant DNA techniques may generate concerns about risk, requiring additional time and resources to resolve. Risk assessments must be conducted prior to releasing transgenic arthropods into the environment for either short term experiments or permanent establishment. Potential risk issues to be resolved include whether: the inserted gene(s) (trait) is stable; the traits can be horizontally transferred to other populations or species; released arthropods will perform as expected (especially with regard to their geographic distribution, host or prey specificity; released arthropods will have unintended environmental effects; and, in the case of short term releases, the released arthropods can be recovered from field sites. If the transgenic arthropods strain(s) perform well in preliminary, short term releases and risk assessments are completed satisfactorily, permanent releases into the environment may follow. Many pest management programs, especially those involving replacement of pest populations by the transgenic population, will require permanent establishment in the environment and the use of 'drive mechanisms', have been proposed to achieve this. Because efficacy can be severely compromised by 'transgene silencing', plant molecular biologists are now attempting to stabilize gene expression by building in 'insulators'. Transgene silencing occurs in Drosophila and will no doubt be a factor in other transgenic arthropods. (author)

  18. Role of arthropod communities in bioenergy crop litter decomposition†.

    Science.gov (United States)

    Zangerl, Arthur R; Miresmailli, Saber; Nabity, Paul; Lawrance, Allen; Yanahan, Alan; Mitchell, Corey A; Anderson-Teixeira, Kristina J; David, Mark B; Berenbaum, May R; DeLucia, Evan H

    2013-10-01

    The extensive land use conversion expected to occur to meet demands for bioenergy feedstock production will likely have widespread impacts on agroecosystem biodiversity and ecosystem services, including carbon sequestration. Although arthropod detritivores are known to contribute to litter decomposition and thus energy flow and nutrient cycling in many plant communities, their importance in bioenergy feedstock communities has not yet been assessed. We undertook an experimental study quantifying rates of litter mass loss and nutrient cycling in the presence and absence of these organisms in three bioenergy feedstock crops-miscanthus (Miscanthus x giganteus), switchgrass (Panicum virgatum), and a planted prairie community. Overall arthropod abundance and litter decomposition rates were similar in all three communities. Despite effective reduction of arthropods in experimental plots via insecticide application, litter decomposition rates, inorganic nitrogen leaching, and carbon-nitrogen ratios did not differ significantly between control (with arthropods) and treatment (without arthropods) plots in any of the three community types. Our findings suggest that changes in arthropod faunal composition associated with widespread adoption of bioenergy feedstock crops may not be associated with profoundly altered arthropod-mediated litter decomposition and nutrient release.

  19. Diversity of arthropod community in transgenic poplar-cotton ecosystems.

    Science.gov (United States)

    Zhang, D J; Lu, Z Y; Liu, J X; Li, C L; Yang, M S

    2015-01-01

    Poplar-cotton agro-ecosystems are the main agricultural planting modes of plain cotton fields in China. Here, we performed a systematic survey of the diversity and population of arthropod communities in four different combination of poplar-cotton eco-systems, including I) non-transgenic poplar and non-transgenic cotton fields; II) non-transgenic poplar and transgenic cotton fields [Bacillus thuringiensis (Bt) cotton]; III) Bt transgenic poplar (high insect resistant strain Pb29) and non-transgenic cotton; and IV) transgenic poplar and transgenic cotton fields, over a period of 3 years. Based on the statistical methods used to investigate community ecology, the effects of transgenic ecosystems on the whole structure of the arthropod community, on the structure of arthropods in the nutritive layer, and on the similarity of arthropod communities were evaluated. The main results were as follows: the transgenic poplar-cotton ecosystem has a stronger inhibitory effect on insect pests and has no impact on the structure of the arthropod community, and therefore, maintains the diversity of the arthropod community. The character index of the community indicated that the structure of the arthropod community of the transgenic poplar-cotton ecosystem was better than that of the poplar-cotton ecosystem, and that system IV had the best structure. As for the abundance of nutritional classes, the transgenic poplar-cotton ecosystem was also better than that of the non-transgenic poplar-cotton ecosystem. The cluster analysis and similarity of arthropod communities between the four different transgenic poplar-cotton ecosystems illustrated that the structure of the arthropod community excelled in the small sample of the transgenic poplar-cotton ecosystems.

  20. Elementary vectors

    CERN Document Server

    Wolstenholme, E Œ

    1978-01-01

    Elementary Vectors, Third Edition serves as an introductory course in vector analysis and is intended to present the theoretical and application aspects of vectors. The book covers topics that rigorously explain and provide definitions, principles, equations, and methods in vector analysis. Applications of vector methods to simple kinematical and dynamical problems; central forces and orbits; and solutions to geometrical problems are discussed as well. This edition of the text also provides an appendix, intended for students, which the author hopes to bridge the gap between theory and appl

  1. A versatile vector set for animal transgenesis.

    Science.gov (United States)

    Horn, C; Wimmer, E A

    2000-12-01

    Genetic manipulation of a series of diverged arthropods is a highly desirable goal for a better understanding of developmental and evolutionary processes. A major obstacle so far has been the difficulty in obtaining marker genes that allow easy and reliable identification of transgenic animals. Here, we present a versatile vector set for germline transformation based on the promiscuous transposons mariner, Hermes and piggyBac. Into these vectors, we introduced a potentially universal marker system that is comprised of an artificial promoter containing three Pax-6 homodimer binding sites. This promoter drives strong expression of spectral variants of the enhanced green fluorescent protein (EGFP) in larval, pupal, and adult photoreceptors. Using special filter sets, the yellow (EYFP) and cyan (ECFP) variant are fully distinguishable and therefore represent a separable pair of markers. Furthermore, we adapted a simple plasmid-based transposition assay system to enable quick functional tests of our vectors in different arthropod species before employing them in more laborious germline transformation experiments. Using this system we demonstrate that our vectors transpose in both Drosophila melanogaster and Drosophila virilis.

  2. Repeated Raking of Pine Plantations Alters Soil Arthropod Communities

    OpenAIRE

    Holly K. Ober; Lucas W. DeGroote

    2014-01-01

    Terrestrial arthropods in forests are engaged in vital ecosystem functions that ultimately help maintain soil productivity. Repeated disturbance can cause abrupt and irreversible changes in arthropod community composition and thereby alter trophic interactions among soil fauna. An increasingly popular means of generating income from pine plantations in the Southeastern U.S. is annual raking to collect pine litter. We raked litter once per year for three consecutive years in the pine plantatio...

  3. Arthropod responses to the experimental isolation of Amazonian forest fragments

    Directory of Open Access Journals (Sweden)

    Heraldo L. Vasconcelos

    2012-12-01

    Full Text Available Arthropods are the most diverse and abundant group of animals found in tropical lowland forests, and in light of ongoing global change phenomena, it is essential to better understand their responses to anthropogenic disturbances. Here we present a review of arthropod responses to forest deforestation and fragmentation based on studies conducted at the Biological Dynamics of Forest Fragments Project (BDFFP, located in central Amazonia. These studies involved a wide range of arthropod groups. All but one of the studies evaluated changes in total species number or species density in relation to fragment size, (i.e. area effects, and one-third also evaluated edge effects. Our review indicates that almost every arthropod group studied showed some kind of response to reduction in forest area, including altered abundances, species richness or composition in comparisons of different-sized fragments, fragmented and non-fragmented areas, or comparisons of forest edges and forest interiors. These responses tended to be idiosyncratic, with some groups showing predicted declines in abundance or diversity in the fragments while others show no response or even increases. However, some of the observed effects on arthropods, or on the ecological processes in which they are involved, were transient. The most likely explanation for this was the rapid development of secondary growth around fragments, which greatly increased the connectivity between fragments and the remaining forest. Although the BDFFP has provided many insights regarding the effects of forest fragmentation on arthropod assemblages, many diverse groups, such as canopy arthropods, have received scant attention. For those that have been studied, much remains to be learned regarding the long-term dynamics of these assemblages and how landscape context influences local biodiversity. The BDFFP remains an exceptional site in which to investigate how the ecological interactions in which arthropods are

  4. Vector analysis

    CERN Document Server

    Brand, Louis

    2006-01-01

    The use of vectors not only simplifies treatments of differential geometry, mechanics, hydrodynamics, and electrodynamics, but also makes mathematical and physical concepts more tangible and easy to grasp. This text for undergraduates was designed as a short introductory course to give students the tools of vector algebra and calculus, as well as a brief glimpse into these subjects' manifold applications. The applications are developed to the extent that the uses of the potential function, both scalar and vector, are fully illustrated. Moreover, the basic postulates of vector analysis are brou

  5. The insect microbiome modulates vector competence for arboviruses.

    Science.gov (United States)

    Jupatanakul, Natapong; Sim, Shuzhen; Dimopoulos, George

    2014-11-11

    Diseases caused by arthropod-borne viruses (arboviruses), such as Dengue, West Nile, and Chikungunya, constitute a major global health burden and are increasing in incidence and geographic range. The natural microbiota of insect vectors influences various aspects of host biology, such as nutrition, reproduction, metabolism, and immunity, and recent studies have highlighted the ability of insect-associated bacteria to reduce vector competence for arboviruses and other pathogens. This reduction can occur through mechanisms, such as immune response activation, resource competition, or the production of anti-viral molecules. Studying the interactions between insect vectors and their microbiota is an important step toward developing alternative strategies for arbovirus transmission control.

  6. The tortoise or the hare? Impacts of within-host dynamics on transmission success of arthropod-borne viruses.

    Science.gov (United States)

    Althouse, Benjamin M; Hanley, Kathryn A

    2015-08-19

    Arthropod-borne viruses (arboviruses) are maintained in a cycle of alternating transmission between vertebrate hosts and arthropod vectors. Arboviruses possess RNA genomes capable of rapid diversification and adaptation, and the between-host trade-offs inherent to host alternation impose well-documented constraints on arbovirus evolution. Here, we investigate the less well-studied within-host trade-offs that shape arbovirus replication dynamics and transmission. Arboviruses generally establish lifelong infection in vectors but transient infection of variable magnitude (i.e. peak virus concentration) and duration in vertebrate hosts. In the majority of experimental infections of vertebrate hosts, both the magnitude and duration of arbovirus replication depended upon the dose of virus administered, with increasing dose resulting in greater magnitude but shorter duration of viraemia. This pattern suggests that the vertebrate immune response imposes a trade-off between the height and breadth of the virus replication curve. To investigate the impact of this trade-off on transmission, we used a simple modelling approach to contrast the effect of 'tortoise' (low magnitude, long duration viraemia) and 'hare' (high magnitude, short duration viraemia) arbovirus replication strategies on transmission. This model revealed that, counter to previous theory, arboviruses that adopt a tortoise strategy have higher rates of persistence in both host and vector populations.

  7. The role of ecological infrastructure on beneficial arthropods in vineyards

    Directory of Open Access Journals (Sweden)

    Gabrijela Kuštera

    2016-03-01

    Full Text Available Weeds and non-cultivated plants have a great impact on abundance and diversity of beneficial arthropods in agriculture. The main aim of this work was to study the influence of the ecological infrastructure (meadows and weedy margins on the arthropod composition in vineyard surrounding landscape. Research was carried out from May to October during three years. Sampling took place in the ecological infrastructure of three differently managed vineyards (organic, integrated and extensive. Three zones were chosen in each vineyard (3 m, 10 m, and 30 m from the edge of the vineyard. Samples were taken using a standardised sweep net method. In total, we captured 6032 spiders and 1309 insects belonging to 4 orders and 10 families. Arthropod fauna was numerically dominated by Aranea (82.1%; among insects, Coleoptera was the most abundant taxonomic group (10.6%; Neuroptera showed the lowest value (0.88%. Significant differences were found between sites and zones. Organic vineyard showed the highest abundance of arthropods (92.41% were spiders and in the integrated vineyard there was a 23% of insects. Both the highest abundance of arthropods and the highest Shannon Index value (2.46 was found 3 m away from the edge of the vineyard. Results showed that spiders were the dominant arthropods and ladybugs the dominant insects. Weedy strips near the edge of the vineyard contained a high number of insects and spiders. Our results support the importance of weedy margins in enhancing the population of arthropods as well as in biodiversity promotion. Well-managed field margins could play important role in biological control of vineyard pests.

  8. The non-target impact of spinosyns on beneficial arthropods.

    Science.gov (United States)

    Biondi, Antonio; Mommaerts, Veerle; Smagghe, Guy; Viñuela, Elisa; Zappalà, Lucia; Desneux, Nicolas

    2012-12-01

    Spinosyn-based products, mostly spinosad, have been widely recommended by extension specialists and agribusiness companies; consequently, they have been used to control various pests in many different cropping systems. Following the worldwide adoption of spinosad-based products for integrated and organic farming, an increasing number of ecotoxicological studies have been published in the past 10 years. These studies are primarily related to the risk assessment of spinosad towards beneficial arthropods. This review takes into account recent data with the aim of (i) highlighting potentially adverse effects of spinosyns on beneficial arthropods (and hence on ecosystem services that they provide in agroecosystems), (ii) clarifying the range of methods used to address spinosyn side effects on biocontrol agents and pollinators in order to provide new insights for the development of more accurate bioassays, (iii) identifying pitfalls when analysing laboratory results to assess field risks and (iv) gaining increasing knowledge on side effects when using spinosad for integrated pest management (IPM) programmes and organic farming. For the first time, a thorough review of possible risks of spinosad and novel spinosyns (such as spinetoram) to beneficial arthropods (notably natural enemies and pollinators) is provided. The acute lethal effect and multiple sublethal effects have been identified in almost all arthropod groups studied. This review will help to optimise the future use of spinosad and new spinosyns in IPM programmes and for organic farming, notably by preventing the possible side effects of spinosyns on beneficial arthropods.

  9. Exoskeletons and economics: indoor arthropod diversity increases in affluent neighbourhoods.

    Science.gov (United States)

    Leong, Misha; Bertone, Matthew A; Bayless, Keith M; Dunn, Robert R; Trautwein, Michelle D

    2016-08-01

    In urban ecosystems, socioeconomics contribute to patterns of biodiversity. The 'luxury effect', in which wealthier neighbourhoods are more biologically diverse, has been observed for plants, birds, bats and lizards. Here, we used data from a survey of indoor arthropod diversity (defined throughout as family-level richness) from 50 urban houses and found that house size, surrounding vegetation, as well as mean neighbourhood income best predict the number of kinds of arthropods found indoors. Our finding, that homes in wealthier neighbourhoods host higher indoor arthropod diversity (consisting of primarily non-pest species), shows that the luxury effect can extend to the indoor environment. The effect of mean neighbourhood income on indoor arthropod diversity was particularly strong for individual houses that lacked high surrounding vegetation ground cover, suggesting that neighbourhood dynamics can compensate for local choices of homeowners. Our work suggests that the management of neighbourhoods and cities can have effects on biodiversity that can extend from trees and birds all the way to the arthropod life in bedrooms and basements.

  10. Epigeic soil arthropod abundance under different agricultural land uses

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Bote, J. L.; Romero, A. J.

    2012-11-01

    The study of soil arthropods can provide valuable information how ecosystems respond to different management practices. The objective was to assess the total abundance, richness, and composition of epiedaphic arthropods in different agrosystems from southwestern Spain. Six sites with different agricultural uses were selected: olive grove, vineyards, olive grove with vineyards, wheat fields, fallows (150-300 m long), and abandoned vineyards. Crops were managed in extensive. Field margins were used as reference habitats. At the seven sites a total of 30 pitfall traps were arranged in a 10 × 3 grid. Traps were arranged to short (SD, 1 m), medium (MD, 6 m) and large (LD, 11 m) distance to the field margins in the middle of selected plots. Pitfall traps captured a total of 11,992 edaphic arthropods belonging to 11 different taxa. Soil fauna was numerically dominated by Formicidae (26.60%), Coleoptera (19.77%), and Aranae (16.76%). The higher number of soil arthropods were captured in the field margins followed by the abandoned vineyard. Significant differences were found between sites for total abundance, and zones. However, no significant differences for total abundance were found between months (April-July). Richness and diversity was highest in field margins and abandoned vineyards. Significant differences were found for these variables between sites. Our results suggest that agricultural intensification affects soil arthropods in Tierra de Barros area, a taxonomic group with an important role in the functioning of agricultural ecosystems. (Author) 32 refs.

  11. Exoskeletons and economics: indoor arthropod diversity increases in affluent neighbourhoods.

    Science.gov (United States)

    Leong, Misha; Bertone, Matthew A; Bayless, Keith M; Dunn, Robert R; Trautwein, Michelle D

    2016-08-01

    In urban ecosystems, socioeconomics contribute to patterns of biodiversity. The 'luxury effect', in which wealthier neighbourhoods are more biologically diverse, has been observed for plants, birds, bats and lizards. Here, we used data from a survey of indoor arthropod diversity (defined throughout as family-level richness) from 50 urban houses and found that house size, surrounding vegetation, as well as mean neighbourhood income best predict the number of kinds of arthropods found indoors. Our finding, that homes in wealthier neighbourhoods host higher indoor arthropod diversity (consisting of primarily non-pest species), shows that the luxury effect can extend to the indoor environment. The effect of mean neighbourhood income on indoor arthropod diversity was particularly strong for individual houses that lacked high surrounding vegetation ground cover, suggesting that neighbourhood dynamics can compensate for local choices of homeowners. Our work suggests that the management of neighbourhoods and cities can have effects on biodiversity that can extend from trees and birds all the way to the arthropod life in bedrooms and basements. PMID:27484644

  12. The occurrence of arthropods in processed rice products in Malaysia

    Institute of Scientific and Technical Information of China (English)

    Mariana A; Heah SK; Wong AL; Ho TM

    2010-01-01

    Objective:To determine distribution of arthropods in processed rice products such as rice flour and rice cereal-based infant food. Methods: Random samples of rice flour and rice cereal-based infant food purchased from commercial outlets were examined for the presence of arthropods using a modified Berlese Tullgren Funnel Method. Mites were mounted prior to identification and weevils were directly identified. Results: For non-expired products, infestation was found in 6.7%of rice flour and none was found in rice cereal-based infant food samples. The arthropods found in the flour samples were Cheyletus spp., Suidasia pontifica (S. pontifica), Tarsonemus spp., Tyrophagus putrescentiae (T. putrescentiae), Sitophilus granarius (S. granarius) and Sitophilus oryzae (S. oryzae). Others which cannot be identified were Oribatid and Prostigmatid mites. The most common mites in rice flour were Tarsonemus spp. (69.1%), followed by S. pontifica (18.2%). For expired products, only one sample of rice cereal-based infant food was infested and the infestation was by mites of the family Tydeidae. Conclusions:This study demonstrates the presence of 4 allergenic species of S. pontifica, T. putrescentiae, S. granarius and S. oryzae in rice flour. These arthropods can contribute to the incidence of anaphylaxis upon consumption by atopic individuals. There was no infestation of arthropods in rice cereal-based infant food surveyed except for an expired product in a moderate rusty tin container.

  13. Exoskeletons and economics: indoor arthropod diversity increases in affluent neighbourhoods

    Science.gov (United States)

    Bertone, Matthew A.; Bayless, Keith M.; Dunn, Robert R.; Trautwein, Michelle D.

    2016-01-01

    In urban ecosystems, socioeconomics contribute to patterns of biodiversity. The ‘luxury effect’, in which wealthier neighbourhoods are more biologically diverse, has been observed for plants, birds, bats and lizards. Here, we used data from a survey of indoor arthropod diversity (defined throughout as family-level richness) from 50 urban houses and found that house size, surrounding vegetation, as well as mean neighbourhood income best predict the number of kinds of arthropods found indoors. Our finding, that homes in wealthier neighbourhoods host higher indoor arthropod diversity (consisting of primarily non-pest species), shows that the luxury effect can extend to the indoor environment. The effect of mean neighbourhood income on indoor arthropod diversity was particularly strong for individual houses that lacked high surrounding vegetation ground cover, suggesting that neighbourhood dynamics can compensate for local choices of homeowners. Our work suggests that the management of neighbourhoods and cities can have effects on biodiversity that can extend from trees and birds all the way to the arthropod life in bedrooms and basements. PMID:27484644

  14. Equivalent Vectors

    Science.gov (United States)

    Levine, Robert

    2004-01-01

    The cross-product is a mathematical operation that is performed between two 3-dimensional vectors. The result is a vector that is orthogonal or perpendicular to both of them. Learning about this for the first time while taking Calculus-III, the class was taught that if AxB = AxC, it does not necessarily follow that B = C. This seemed baffling. The…

  15. Inbreeding and the evolution of sociality in arthropods

    Science.gov (United States)

    Tabadkani, Seyed Mohammad; Nozari, Jamasb; Lihoreau, Mathieu

    2012-10-01

    Animals have evolved strategies to optimally balance costs and benefits of inbreeding. In social species, these adaptations can have a considerable impact on the structure, the organization, and the functioning of groups. Here, we consider how selection for inbreeding avoidance fashions the social behavior of arthropods, a phylum exhibiting an unparalleled richness of social lifestyles. We first examine life histories and parental investment patterns determining whether individuals should actively avoid or prefer inbreeding. Next, we illustrate the diversity of inbreeding avoidance mechanisms in arthropods, from the dispersal of individuals to the rejection of kin during mate choice and the production of unisexual broods by females. Then, we address the particular case of haplodiploid insects. Finally, we discuss how inbreeding may drive and shape the evolution of arthropods societies along two theoretical pathways.

  16. [Diversity and stability of arthropod assemblage in tea orchard].

    Science.gov (United States)

    Chen, Yigen; Xiong, Jinjun; Huang, Mingdu; Gu, Dejiu

    2004-05-01

    Two tea orchards, simplex tea orchard with weeds removed manually or by herbicides (STO) and complex tea orchard with the weed Hedyotis uncinella (CTO), each with an area of 0. 4 hm2, were established in 1995 in Yingde Hongxing Tea Plantation, Guangdong Province. The primary eigenvalues, species richness index (R), assemblage diversity index (H'), evenness index (J) and species concentration index (C) of arthropod assemblage were employed and compared to assess the efficacy of STO and CTO on the diversity and stabilityof arthropod assemblage. Stability indexes Ss/Si and Sn/Sp and variation coefficient of diversity index ds/dm were utilized as well. The results demonstrated that the R of arthropod assemblage in CTO ranged from 4 to 8, with the highest of 7.7403, while that in STO varied mainly between 4 to 6. The average R of arthropod assemblage in CTO was 5.4672 +/- 0.3483, higher than that in STO (4.8809 +/- 0.3175). The H' of arthropod in CTO (3.8535 +/- 0.1232) was higher, in contrast to the value in STO (3.4654 +/- 0.1856). The J in CTO was higher, while the species concentration index (C) was lower, in comparison to STO. The stability indexes Ss/Si and Sn/Sp of CTO were greater than those of STO, while the ds/dm in CTO (0.1107) was lower than that in STO (0.1855). All these indicated that the diversity of arthropod assemblage was better preserved in CTO, and the assemblage in CTO was more stable.

  17. [2013 update about arthropod envenomations in French Guyana].

    Science.gov (United States)

    Ganteaume, F; Imbert, C

    2014-02-01

    French Guiana, by its geographical situation, its climate and its biodiversity, is often called "the green hell". Indeed, this French department of America shelters a wildlife rich, abundant among which many species of arthropods, some of which are responsible for envenomations. These accidents consist of scorpion's or hymenoptera's stings or spider's bites. The associated clinical aspect is variable, from simple pain to circulatory collapse, or lung oedema. However, symptomatology is generally mild; four deaths associated to arthropod envenomations have been reported in the past 25 years. This article focuses on envenomations in French Guiana, describing favoring human behavior, risks and venoms associated with the main related animal species.

  18. [2013 update about arthropod envenomations in French Guyana].

    Science.gov (United States)

    Ganteaume, F; Imbert, C

    2014-02-01

    French Guiana, by its geographical situation, its climate and its biodiversity, is often called "the green hell". Indeed, this French department of America shelters a wildlife rich, abundant among which many species of arthropods, some of which are responsible for envenomations. These accidents consist of scorpion's or hymenoptera's stings or spider's bites. The associated clinical aspect is variable, from simple pain to circulatory collapse, or lung oedema. However, symptomatology is generally mild; four deaths associated to arthropod envenomations have been reported in the past 25 years. This article focuses on envenomations in French Guiana, describing favoring human behavior, risks and venoms associated with the main related animal species. PMID:24415535

  19. The role of RNA interference (RNAi) in arbovirus-vector interactions.

    Science.gov (United States)

    Blair, Carol D; Olson, Ken E

    2015-02-17

    RNA interference (RNAi) was shown over 18 years ago to be a mechanism by which arbovirus replication and transmission could be controlled in arthropod vectors. During the intervening period, research on RNAi has defined many of the components and mechanisms of this antiviral pathway in arthropods, yet a number of unexplored questions remain. RNAi refers to RNA-mediated regulation of gene expression. Originally, the term described silencing of endogenous genes by introduction of exogenous double-stranded (ds)RNA with the same sequence as the gene to be silenced. Further research has shown that RNAi comprises three gene regulation pathways that are mediated by small RNAs: the small interfering (si)RNA, micro (mi)RNA, and Piwi-interacting (pi)RNA pathways. The exogenous (exo-)siRNA pathway is now recognized as a major antiviral innate immune response of arthropods. More recent studies suggest that the piRNA and miRNA pathways might also have important roles in arbovirus-vector interactions. This review will focus on current knowledge of the role of the exo-siRNA pathway as an arthropod vector antiviral response and on emerging research into vector piRNA and miRNA pathway modulation of arbovirus-vector interactions. Although it is assumed that arboviruses must evade the vector's antiviral RNAi response in order to maintain their natural transmission cycles, the strategies by which this is accomplished are not well defined. RNAi is also an important tool for arthropod gene knock-down in functional genomics studies and in development of arbovirus-resistant mosquito populations. Possible arbovirus strategies for evasion of RNAi and applications of RNAi in functional genomics analysis and arbovirus transmission control will also be reviewed.

  20. Canopy arthropods community within and among oak species in central Mexico

    OpenAIRE

    Efraín TOVAR-SANCHEZ

    2009-01-01

    Quercus rugosa and Q.laurina are species that presents a wide geographical distribution range in temperate forests of Mexico. Oak canopies contain a considerable portion of arthropod diversity and the arthropods fauna fulfill a wide variety of ecological roles. We examined the effect of oak species and seasonal changes on some community structure parameters (diversity, composition, similarity, biomass, rare species, and density of arthropod fauna) of canopy arthropods. In total, 40 oak ca...

  1. Genomic insights into the Ixodes scapularis tick vector of Lyme disease

    DEFF Research Database (Denmark)

    Gulia-Nuss, Monika; Nuss, Andrew B; Meyer, Jason M;

    2016-01-01

    Ticks transmit more pathogens to humans and animals than any other arthropod. We describe the 2.1 Gbp nuclear genome of the tick, Ixodes scapularis (Say), which vectors pathogens that cause Lyme disease, human granulocytic anaplasmosis, babesiosis and other diseases. The large genome reflects acc...

  2. Molecular entomology: analyzing tiny molecules to answer big questions about disease vectors and their biology

    Science.gov (United States)

    The entomologists at the Arthropod-Borne Animal Diseases Research Unit at USDA-Agricultural Research Service are tasked with protecting the nation’s livestock from domestic, foreign and emerging vector-borne diseases. To accomplish this task, a vast array of molecular techniques are being used in pr...

  3. Vector geometry

    CERN Document Server

    Robinson, Gilbert de B

    2011-01-01

    This brief undergraduate-level text by a prominent Cambridge-educated mathematician explores the relationship between algebra and geometry. An elementary course in plane geometry is the sole requirement for Gilbert de B. Robinson's text, which is the result of several years of teaching and learning the most effective methods from discussions with students. Topics include lines and planes, determinants and linear equations, matrices, groups and linear transformations, and vectors and vector spaces. Additional subjects range from conics and quadrics to homogeneous coordinates and projective geom

  4. Stable isotope methods in biological and ecological studies of arthropods

    NARCIS (Netherlands)

    Hood-Nowotny, R.C.; Knols, B.G.J.

    2007-01-01

    This is an eclectic review and analysis of contemporary and promising stable isotope methodologies to study the biology and ecology of arthropods. It is augmented with literature from other disciplines, indicative of the potential for knowledge transfer. It is demonstrated that stable isotopes can b

  5. Arthropods associated with medicinal plants in coastal South Carolina

    Institute of Scientific and Technical Information of China (English)

    ROLANDO LOPEZ; B. MERLE SHEPARD

    2007-01-01

    Arthropods were sampled from feverfew [Tanacetum parthenium (L.) SchultzBip], Echinaceapurpurea (L.) Moench, Echinaceapallida (Nutt.) Nutt., Valeriana officinalis L., and St. John's wort (Hypericum perforatum L.) during 1998-2001. In addition,arthropods were sampled on tansy (Tanacetum vulgare L.) from 2001-2004. In general,50-60 arthropod species where collected and identified among all of the medicinal plant species. Among the predators, Orius insidiosus (Say) (Hemiptera: Anthocoridae), Geocoris punctipes (Say) (Hemiptera: Lygaeidae) and spiders were most abundant from 1998-2004.The three-cornered alfalfa hopper, Spissistilus festinus (Say), was the most abundant herbivore found from 1998 to 2001. Orius insidiosus and G. punctipes were 3-4 times more abundant on T. parthenium than on any other medicinal plant species. Based on the numbers of predatory arthropods found on T. parthenium, this crop could be suitable as a companion or "banker" plant to attract and maintain populations of predators, especially O. insidiosus and G. punctipes. Whitefly nymphs attacked by predators with piercing/sucking mouthparts are easily identified using a microscope because of the general appearance of the carcass left by the predators. Thus, populations of predators on T. parthenium suppressed Bemisia tabaci populations on E. purpurea when these crops were planted as companion crops.

  6. Soluble proteins of chemical communication: an overview across arthropods

    Directory of Open Access Journals (Sweden)

    Paolo ePelosi

    2014-08-01

    Full Text Available Detection of chemical signals both in insects and in vertebrates is mediated by soluble proteins, highly concentrated in olfactory organs, which bind semiochemicals and activate, with still largely unknown mechanisms, specific chemoreceptors. The same proteins are often found in structures where pheromones are synthesised and released, where they likely perform a second role in solubilising and delivering chemical messengers in the environment.A single class of soluble polypeptides, called Odorant-Binding Proteins (OBPs is known in vertebrates, while two have been identified in insects, OBPs and CSPs (Chemosensory Proteins. Despite their common name, OBPs of vertebrates bear no structural similarity with those of insects. We observed that in arthropods OBPs are strictly limited to insects, while a few members of the CSP family have been found in crustacean and other arthropods, where however, based on their very limited numbers, a function in chemical communication seems unlikely.The question we address in this review is whether another class of soluble proteins may have been adopted by other arthropods to perform the role of OBPs and CSPs in insects. We propose that lipid-transporter proteins of the Niemann-Pick type C2 family could represent likely candidates and report the results of an analysis of their sequences in representative species of different arthropods.

  7. Injuries caused by arthropods: diagnostic and therapeutic approach in ER

    Directory of Open Access Journals (Sweden)

    Dutto Moreno

    2009-04-01

    Full Text Available Injuries caused by arthropods, primarily insects and arachnids, represent a significant source of lesions and allergies even in Italy, a country that has a negligible number of species with important toxicological characteristics from an emergency medicine point of view; unlike areas such as the Americas or Africa (including northern Africa where highly toxic autochthonous species are present, whose bite or sting can be life-threatening. Medical consultation both in hospital Emergency Rooms and general practitioners’ surgeries is markedly seasonal, occurring mainly in the spring and summer (April – September, consistent with arthropod activity. At the current time, in Italy, urgent acute arthropod-related injuries are rare and usually involve type I hypersensitivity, and in most cases they are localised lesions that cause discomfort. The aim of the article is to briefly summarise the species of insects and arachnids that are most frequently cause for medical consultation in Italy and to provide assistance in the diagnostic and therapeutic plan, focusing in particular on the importance of health education that in many acute arthropod-derived cases can play an important part in preventing reoccurrence.

  8. Horizontal Gene Transfer Contributes to the Evolution of Arthropod Herbivory.

    Science.gov (United States)

    Wybouw, Nicky; Pauchet, Yannick; Heckel, David G; Van Leeuwen, Thomas

    2016-01-01

    Within animals, evolutionary transition toward herbivory is severely limited by the hostile characteristics of plants. Arthropods have nonetheless counteracted many nutritional and defensive barriers imposed by plants and are currently considered as the most successful animal herbivores in terrestrial ecosystems. We gather a body of evidence showing that genomes of various plant feeding insects and mites possess genes whose presence can only be explained by horizontal gene transfer (HGT). HGT is the asexual transmission of genetic information between reproductively isolated species. Although HGT is known to have great adaptive significance in prokaryotes, its impact on eukaryotic evolution remains obscure. Here, we show that laterally transferred genes into arthropods underpin many adaptations to phytophagy, including efficient assimilation and detoxification of plant produced metabolites. Horizontally acquired genes and the traits they encode often functionally diversify within arthropod recipients, enabling the colonization of more host plant species and organs. We demonstrate that HGT can drive metazoan evolution by uncovering its prominent role in the adaptations of arthropods to exploit plants. PMID:27307274

  9. Consequences of cyclic vegetation management for arthropod survival : Simulation experiments

    NARCIS (Netherlands)

    Hinsch, Martin; Poethke, Hans-Joachim

    2007-01-01

    Many rare arthropod species occupy open grasslands. Mowing or grazing is needed to preserve the habitat for these species. Alternatively the vegetation cover in parts of the managed area can be periodically destroyed by ploughing or rototilling. Such treatment results in a dynamic mosaic of habitat

  10. Diet-consumer nitrogen isotope fractionation for prolonged fasting arthropods.

    Science.gov (United States)

    Mizota, Chitoshi; Yamanaka, Toshiro

    2011-12-01

    Nitrogen acquisition for cellular metabolism during diapause is a primary concern for herbivorous arthropods. Analyses of naturally occurring stable isotopes of nitrogen help elucidate the mechanism. Relevant articles have cited (58 times up to mid-June 2011) anomalously elevated δ(15)N (per mil deviation of (15)N/(14)N, relative to atmospheric nitrogen=0 ‰) values (diet-consumer nitrogen isotope fractionation; up to 12 ‰) for a prolonged fasting raspberry beetle (Byturus tomentosus Degeer (Coleoptera: Byturidae)), which feeds on red raspberries (Rubus idaeus: δ(15)N= ~ +2 ‰). Biologists have hypothesised that extensive recycling of amino acid nitrogen is responsible for the prolonged fasting. Since this hypothesis was proposed in 1995, scientists have integrated biochemical and molecular knowledge to support the mechanism of prolonged diapausing of animals. To test the validity of the recycling hypothesis, we analysed tissue nitrogen isotope ratios for four Japanese arthropods: the shield bug Parastrachia japonensis Scott (Hemiptera: Cydnidae), the burrower bug Canthophorus niveimarginatus Scott (Hemiptera: Cydnidae), leaf beetle Gastrophysa atrocyanea Motschulsky (Coleoptera: Chrysomelidae) and the Japanese oak silkworm Antheraea yamamai (Lepidoptera: Saturniidae), all of which fast for more than 6 months as part of their life-history strategy. Resulting diet-consumer nitrogen isotope discrimination during fasting ranged from 0 to 7‰, as in many commonly known terrestrial arthropods. We conclude that prolonged fasting of arthropods does not always result in anomalous diet-consumer nitrogen isotope fractionation, since the recycling process is closed or nearly closed with respect to nitrogen isotopes. PMID:22166153

  11. Cats are not small dogs: is there an immunological explanation for why cats are less affected by arthropod-borne disease than dogs?

    Science.gov (United States)

    Day, Michael J

    2016-09-20

    It is widely recognized that cats appear to be less frequently affected by arthropod-borne infectious diseases than dogs and share fewer zoonotic pathogens with man. This impression is supported by the relative lack of scientific publications related to feline vector-borne infections. This review explores the possible reasons for the difference between the two most common small companion animal species, including the hypothesis that cats might have a genetically-determined immunological resistance to arthropod vectors or the microparasites they transmit. A number of simple possibilities might account for the lower prevalence of these diseases in cats, including factors related to the lifestyle and behaviour of the cat, lesser spend on preventative healthcare for cats and reduced opportunities for research funding for these animals. The dog and cat have substantially similar immune system components, but differences in immune function might in part account for the markedly distinct prevalence and clinicopathological appearance of autoimmune, allergic, idiopathic inflammatory, immunodeficiency, neoplastic and infectious diseases in the two species. Cats have greater genetic diversity than dogs with much lower linkage disequilibrium in feline compared with canine breed groups. Immune function is intrinsically related to the nature of the intestinal microbiome and subtle differences between the canine and feline microbial populations might also impact on immune function and disease resistance. The reasons for the apparent lesser susceptibility of cats to arthropod-borne infectious diseases are likely to be complex, but warrant further investigation.

  12. Cats are not small dogs: is there an immunological explanation for why cats are less affected by arthropod-borne disease than dogs?

    Science.gov (United States)

    Day, Michael J

    2016-01-01

    It is widely recognized that cats appear to be less frequently affected by arthropod-borne infectious diseases than dogs and share fewer zoonotic pathogens with man. This impression is supported by the relative lack of scientific publications related to feline vector-borne infections. This review explores the possible reasons for the difference between the two most common small companion animal species, including the hypothesis that cats might have a genetically-determined immunological resistance to arthropod vectors or the microparasites they transmit. A number of simple possibilities might account for the lower prevalence of these diseases in cats, including factors related to the lifestyle and behaviour of the cat, lesser spend on preventative healthcare for cats and reduced opportunities for research funding for these animals. The dog and cat have substantially similar immune system components, but differences in immune function might in part account for the markedly distinct prevalence and clinicopathological appearance of autoimmune, allergic, idiopathic inflammatory, immunodeficiency, neoplastic and infectious diseases in the two species. Cats have greater genetic diversity than dogs with much lower linkage disequilibrium in feline compared with canine breed groups. Immune function is intrinsically related to the nature of the intestinal microbiome and subtle differences between the canine and feline microbial populations might also impact on immune function and disease resistance. The reasons for the apparent lesser susceptibility of cats to arthropod-borne infectious diseases are likely to be complex, but warrant further investigation. PMID:27646278

  13. Leaf litter arthropod responses to tropical forest restoration.

    Science.gov (United States)

    Cole, Rebecca J; Holl, Karen D; Zahawi, Rakan A; Wickey, Philipp; Townsend, Alan R

    2016-08-01

    Soil and litter arthropods represent a large proportion of tropical biodiversity and perform important ecosystem functions, but little is known about the efficacy of different tropical forest restoration strategies in facilitating their recovery in degraded habitats. We sampled arthropods in four 7- to 8-year-old restoration treatments and in nearby reference forests. Sampling was conducted during the wet and dry seasons using extractions from litter and pitfall samples. Restoration treatments were replicated in 50 × 50-m plots in four former pasture sites in southern Costa Rica: plantation - trees planted throughout the plot; applied nucleation/islands - trees planted in patches of different sizes; and natural regeneration - no tree planting. Arthropod abundance, measures of richness and diversity, and a number of functional groups were greater in the island treatment than in natural regeneration or plantation treatments and, in many cases, were similar to reference forest. Litter and pitfall morphospecies and functional group composition in all three restoration treatments were significantly different than reference sites, but island and plantation treatments showed more recovery than natural regeneration. Abundance and functional group diversity showed a much greater degree of recovery than community composition. Synthesis and applications: The less resource-intensive restoration strategy of planting tree islands was more effective than tree plantations in restoring arthropod abundance, richness, and functional diversity. None of the restoration strategies, however, resulted in similar community composition as reference forest after 8 years of recovery, highlighting the slow rate of recovery of arthropod communities after disturbance, and underscoring the importance of conservation of remnant forests in fragmented landscapes. PMID:27551373

  14. Phylogenetic relationships of the Wolbachia of nematodes and arthropods.

    Directory of Open Access Journals (Sweden)

    Katelyn Fenn

    2006-10-01

    Full Text Available Wolbachia are well known as bacterial symbionts of arthropods, where they are reproductive parasites, but have also been described from nematode hosts, where the symbiotic interaction has features of mutualism. The majority of arthropod Wolbachia belong to clades A and B, while nematode Wolbachia mostly belong to clades C and D, but these relationships have been based on analysis of a small number of genes. To investigate the evolution and relationships of Wolbachia symbionts we have sequenced over 70 kb of the genome of wOvo, a Wolbachia from the human-parasitic nematode Onchocerca volvulus, and compared the genes identified to orthologues in other sequenced Wolbachia genomes. In comparisons of conserved local synteny, we find that wBm, from the nematode Brugia malayi, and wMel, from Drosophila melanogaster, are more similar to each other than either is to wOvo. Phylogenetic analysis of the protein-coding and ribosomal RNA genes on the sequenced fragments supports reciprocal monophyly of nematode and arthropod Wolbachia. The nematode Wolbachia did not arise from within the A clade of arthropod Wolbachia, and the root of the Wolbachia clade lies between the nematode and arthropod symbionts. Using the wOvo sequence, we identified a lateral transfer event whereby segments of the Wolbachia genome were inserted into the Onchocerca nuclear genome. This event predated the separation of the human parasite O. volvulus from its cattle-parasitic sister species, O. ochengi. The long association between filarial nematodes and Wolbachia symbionts may permit more frequent genetic exchange between their genomes.

  15. Canine vector-borne diseases in Brazil

    Directory of Open Access Journals (Sweden)

    Dantas-Torres Filipe

    2008-08-01

    Full Text Available Abstract Canine vector-borne diseases (CVBDs are highly prevalent in Brazil and represent a challenge to veterinarians and public health workers, since some diseases are of great zoonotic potential. Dogs are affected by many protozoa (e.g., Babesia vogeli, Leishmania infantum, and Trypanosoma cruzi, bacteria (e.g., Anaplasma platys and Ehrlichia canis, and helminths (e.g., Dirofilaria immitis and Dipylidium caninum that are transmitted by a diverse range of arthropod vectors, including ticks, fleas, lice, triatomines, mosquitoes, tabanids, and phlebotomine sand flies. This article focuses on several aspects (etiology, transmission, distribution, prevalence, risk factors, diagnosis, control, prevention, and public health significance of CVBDs in Brazil and discusses research gaps to be addressed in future studies.

  16. ArthropodaCyc: a CycADS powered collection of BioCyc databases to analyse and compare metabolism of arthropods.

    Science.gov (United States)

    Baa-Puyoulet, Patrice; Parisot, Nicolas; Febvay, Gérard; Huerta-Cepas, Jaime; Vellozo, Augusto F; Gabaldón, Toni; Calevro, Federica; Charles, Hubert; Colella, Stefano

    2016-01-01

    Arthropods interact with humans at different levels with highly beneficial roles (e.g. as pollinators), as well as with a negative impact for example as vectors of human or animal diseases, or as agricultural pests. Several arthropod genomes are available at present and many others will be sequenced in the near future in the context of the i5K initiative, offering opportunities for reconstructing, modelling and comparing their metabolic networks. In-depth analysis of these genomic data through metabolism reconstruction is expected to contribute to a better understanding of the biology of arthropods, thereby allowing the development of new strategies to control harmful species. In this context, we present here ArthropodaCyc, a dedicated BioCyc collection of databases using the Cyc annotation database system (CycADS), allowing researchers to perform reliable metabolism comparisons of fully sequenced arthropods genomes. Since the annotation quality is a key factor when performing such global genome comparisons, all proteins from the genomes included in the ArthropodaCyc database were re-annotated using several annotation tools and orthology information. All functional/domain annotation results and their sources were integrated in the databases for user access. Currently, ArthropodaCyc offers a centralized repository of metabolic pathways, protein sequence domains, Gene Ontology annotations as well as evolutionary information for 28 arthropod species. Such database collection allows metabolism analysis both with integrated tools and through extraction of data in formats suitable for systems biology studies.Database URL: http://arthropodacyc.cycadsys.org/. PMID:27242037

  17. Importance of mosquito “quasispecies” in selecting an epidemic arthropod-borne virus

    Science.gov (United States)

    Vazeille, Marie; Zouache, Karima; Vega-Rúa, Anubis; Thiberge, Jean-Michel; Caro, Valérie; Yébakima, André; Mousson, Laurence; Piorkowski, Géraldine; Dauga, Catherine; Vaney, Marie-Christine; Manni, Mosè; Gasperi, Giuliano; de Lamballerie, Xavier; Failloux, Anna-Bella

    2016-01-01

    Most arthropod-borne viruses (arboviruses), perpetuated by alternation between a vertebrate host and an insect vector, are likely to emerge through minor genetic changes enabling the virus to adapt to new hosts. In the past decade, chikungunya virus (CHIKV; Alphavirus, Togaviridae) has emerged on La Réunion Island following the selection of a unique substitution in the CHIKV E1 envelope glycoprotein (E1-A226V) of an East-Central-South African (ECSA) genotype conferring a higher transmission rate by the mosquito Aedes albopictus. Assumed to have occurred independently on at least four separate occasions, this evolutionary convergence was suspected to be responsible for CHIKV worldwide expansion. However, assumptions on CHIKV emergence were mainly based on viral genetic changes and the role of the mosquito population quasispecies remained unexplored. Here we show that the nature of the vector population is pivotal in selecting the epidemic CHIKV. We demonstrate using microsatellites mosquito genotyping that Ae. albopictus populations are genetically differentiated, contributing to explain their differential ability to select the E1-226V mutation. Aedes albopictus, newly introduced in Congo coinciding with the first CHIKV outbreak, was not able to select the substitution E1-A226V nor to preferentially transmit a CHIKV clone harboring the E1-226V as did Ae. albopictus from La Réunion. PMID:27383735

  18. Seasonal drivers of the epidemiology of arthropod-borne viruses in Australia.

    Directory of Open Access Journals (Sweden)

    Jemma L Geoghegan

    2014-11-01

    Full Text Available Arthropod-borne viruses are a major cause of emerging disease with significant public health and economic impacts. However, the factors that determine their activity and seasonality are not well understood. In Australia, a network of sentinel cattle herds is used to monitor the distribution of several such viruses and to define virus-free regions. Herein, we utilize these serological data to describe the seasonality, and its drivers, of three economically important animal arboviruses: bluetongue virus, Akabane virus and bovine ephemeral fever virus. Through epidemiological time-series analyses of sero-surveillance data of 180 sentinel herds between 2004-2012, we compared seasonal parameters across latitudes, ranging from the tropical north (-10°S to the more temperate south (-40°S. This analysis revealed marked differences in seasonality between distinct geographic regions and climates: seasonality was most pronounced in southern regions and gradually decreased as latitude decreased toward the Equator. Further, we show that both the timing of epidemics and the average number of seroconversions have a strong geographical component, which likely reflect patterns of vector abundance through co-varying climatic factors, especially temperature and rainfall. Notably, despite their differences in biology, including insect vector species, all three viruses exhibited very similar seasonality. By revealing the factors that shape spatial and temporal distributions, our study provides a more complete understanding of arbovirus seasonality that will enable better risk predictions.

  19. [Exposure degree of important non-target arthropods to Cry2Aa in Bt rice fields].

    Science.gov (United States)

    Zhang, Qing-Ling; Li, Yun-He; Hua, Hong-Xia; Yang, Chang-Ju; Wu, Hong-Jin; Peng, Yu-Fa

    2013-06-01

    Based on the principle of "risk = hazard x exposure", the selected representative nontarget organisms in the assessment of the potential effects of insect-resistant genetically modified (GM) crops on non-target arthropods in laboratory are generally the arthropod species highly exposed to the insecticidal proteins expressed by the GM crops in farmland ecosystem. In order to understand the exposure degree of the important arthropod species to Cry proteins in Bt rice fields, and to select the appropriate non-target arthropods in the risk assessment of insect-resistant GM crops, the enzyme-linked immunosorbent assay (ELISA) was conducted to measure the Cry2Aa protein concentration in the arthropods collected from the cry2Aa rice fields at different rice growth stages. The results showed that there was a significant difference in the Cry2Aa content protein concentration in different arthropod species. Some species did not contain Cry2Aa protein, while some species contained larger amounts of Cry2Aa protein. Relative to the arthropods colleted after rice anthesis, the arthropods colleted in rice anthesis contained relative higher concentrations of Cry2Aa protein, especially for the predacious arthropods. No Cry proteins were detected in parasitic arthropods. This study provided references for the laboratory assessment of the effects of GM rice on nontarget arthropods.

  20. Water balance in desert arthropods. Despite their small size, arthropods may be highly adapted for life in xeric conditions.

    Science.gov (United States)

    Edney, E B

    1967-05-26

    As judged by the number of species, or of individuals, arthropods are an extremely successful group of desert inhabitants. There is very great structural and physiological diversity within the group, and since adaptations to desert life open to one are not open to all. we should not expect to find the maximum possible development of adaptive features in any arthropod simply because it lives in a desert. Most adult insects fly; their larvae and all other arthropods do not, and their adaptations will differ accordingly. Desert beetles have very impermeable cuticles and tolerate high body temperatures, while desert cockroaches live below the sand. have more permeable cuticles, and absorb water vapor. There is probably no single respect in which all desert arthropods differ from insects of other environments. Perhaps a profitable way of viewing desert animals is to recognize that each is a whole organism with a specific collection of adaptations that must be consistent within themselves and which are associated with a specific mode of life and a specific evolutionary history. The arthropod organization is capable of producing highly efficient desert species. There is, however, a converse way of looking at the situation, Which is often neglected but which may be of general biological interest: does the evolution of adaptations to desert environments necessarily involve loss of viability in more mesic habitats? If so, then what are these disavantages- what, for example, is the disadvantage of a highly impermeable cuticle? In some cases the answer is clear: sandroaches need sand dunes to live in because they are morphologically and behaviorly specialized for this habitat. More often the answer is not obvious. PMID:6024185

  1. A novel system for the launch of alphavirus RNA synthesis reveals a role for the Imd pathway in arthropod antiviral response.

    Directory of Open Access Journals (Sweden)

    Vasanthi Avadhanula

    2009-09-01

    Full Text Available Alphaviruses are RNA viruses transmitted between vertebrate hosts by arthropod vectors, primarily mosquitoes. How arthropods counteract alphaviruses or viruses per se is not very well understood. Drosophila melanogaster is a powerful model system for studying innate immunity against bacterial and fungal infections. In this study we report the use of a novel system to analyze replication of Sindbis virus (type species of the alphavirus genus RNA following expression of a Sindbis virus replicon RNA from the fly genome. We demonstrate deficits in the immune deficiency (Imd pathway enhance viral replication while mutations in the Toll pathway fail to affect replication. Similar results were observed with intrathoracic injections of whole virus and confirmed in cultured mosquito cells. These findings show that the Imd pathway mediates an antiviral response to Sindbis virus replication. To our knowledge, this is the first demonstration of an antiviral role for the Imd pathway in insects.

  2. Vector velocimeter

    DEFF Research Database (Denmark)

    2012-01-01

    for generation of a reference beam, a detector system comprising a first detector arrangement arranged in such a way that the signal beam and the reference beam are incident upon the first detector arrangement with the reference beam propagating at an angle relative to a signal beam, and wherein the first......The present invention relates to a compact, reliable and low-cost vector velocimeter for example for determining velocities of particles suspended in a gas or fluid flow, or for determining velocity, displacement, rotation, or vibration of a solid surface, the vector velocimeter comprising a laser...... assembly for emission of a measurement beam for illumination of an object in a measurement volume with coherent light whereby a signal beam emanating from the object in the measurement volume is formed in response to illumination of the object by the measurement beam, a reference beam generator...

  3. Non-insecticide methods for controlling arthropod vectors of zoonotic and other pathogens in layer flocks

    DEFF Research Database (Denmark)

    Sparagano, O. A. E.; Arkle, S.; George, D.;

    of conventional cage housing systems within some EU countries by 2012, means that alternative methods of control for this and similar ectoparasites are urgently needed. Considering that D. gallinae prevalence is generally higher in barn and free-range poultry systems compared to cages, it is becoming increasingly...... to control groups, which may have repercussions upon immunosuppression. Further immunological work is now targeting improvement of the cellular response to limit predation by red mites. A second approach focuses on studying the repellent and toxic effects of some plant-derived products which can be used...... as natural "green" acaricides for managing D. gallinae populations in poultry housing systems. Preliminary work by Kim et al. (2004) tested 56 plant essential oils for their acaricidal effect on D. gallinae. Of these, oils from bay, cade, cinnamon, clove bud, coriander, horseradish, lime dis 5F, mustard...

  4. Combined effects of arthropod herbivores and phytopathogens on plant performance

    DEFF Research Database (Denmark)

    Hauser, Thure Pavlo; Christensen, Stina; Heimes, Christine;

    2013-01-01

    1. Many plants are simultaneously attacked by arthropod herbivores and phytopathogens. These may affect each other directly and indirectly, enhancing or reducing the amount of plant resources they each consume. Ultimately, this may reduce or enhance plant performance relative to what should be ex....... However, as interactive impacts also differed among environments and parasite manipulation methods, this suggests that the ability of plants to compensate such losses may depend on environmental conditions and probably also overall infection load......., the patterns we found were related to plant traits and experimental conditions. 5. Our results suggest that immediate loss of resources from interactions between arthropod herbivores and pathogens is generally moderated by compensation to an extent where there are no interactive effects on plant performance...

  5. Survey of the arthropods on jojoba (Simmondsia chinensis)

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, J.D.; Frommer, S.I.

    1980-02-01

    Simmondsia chinensis (jojoba), a plant native to southwestern North America, has become of economic interest due to the various industrial uses of the unique liquid wax found in its seeds. In a survey of arthropods associated with sylvatic jojoba in California and Arizona, we collected 106 species of insects and mites. Of these, 50 are phytophagous, 29 are parasitic, and 18 are predaceous. Most of the phytophagous species are also known to feed on plants other than jojoba; several of these are notorious generalists. The bionomics of the 4 commonest phytophagous species, Asphondylia n. sp. (Cecidomyiidae), Epinotia kasloana (Olethreutidae), Periploca n. sp. (Walshiidae), and Incisitermes fruticavus (Kalotermitidae) are summarized briefly. None of the phytophagous species were observed to cause extensive damage to sylvatic jojoba. The numerous parasitic and predaceous arthropods probably account for the natural control of many of them. These relationships should be kept in mind when planning future commercial plantations of jojoba.

  6. Fossil calibrations for the arthropod Tree of Life

    OpenAIRE

    Wolfe, JM; Daley, A; Legg, DA; Edgecombe, GD

    2016-01-01

    Fossil age data and molecular sequences are increasingly combined to establish a timescale for the Tree of Life. Arthropods, as the most species-rich and morphologically disparate animal phylum, have received substantial attention, particularly with regard to questions such as the timing of habitat shifts (e.g. terrestrialisation), genome evolution (e.g. gene family duplication and functional evolution), origins of novel characters and behaviours (e.g. wings and flight, venom, silk), biogeogr...

  7. Genetic diversity in aspen and its relation to arthropod abundance.

    Science.gov (United States)

    Zhang, Chunxia; Vornam, Barbara; Volmer, Katharina; Prinz, Kathleen; Kleemann, Frauke; Köhler, Lars; Polle, Andrea; Finkeldey, Reiner

    2014-01-01

    The ecological consequences of biodiversity have become a prominent public issue. Little is known on the effect of genetic diversity on ecosystem services. Here, a diversity experiment was established with European and North American aspen (Populus tremula, P. tremuloides) planted in plots representing either a single deme only or combinations of two, four and eight demes. The goals of this study were to explore the complex inter- and intraspecific genetic diversity of aspen and to then relate three measures for diversity (deme diversity, genetic diversity determined as Shannon index or as expected heterozygosity) to arthropod abundance. Microsatellite and AFLP markers were used to analyze the genetic variation patterns within and between the aspen demes and deme mixtures. Large differences were observed regarding the genetic diversity within demes. An analysis of molecular variance revealed that most of the total genetic diversity was found within demes, but the genetic differentiation among demes was also high. The complex patterns of genetic diversity and differentiation resulted in large differences of the genetic variation within plots. The average diversity increased from plots with only one deme to plots with two, four, and eight demes, respectively and separated plots with and without American aspen. To test whether intra- and interspecific diversity impacts on ecosystem services, arthropod abundance was determined. Increasing genetic diversity of aspen was related to increasing abundance of arthropods. However, the relationship was mainly driven by the presence of American aspen suggesting that species identity overrode the effect of intraspecific variation of European aspen.

  8. Parallel evolution of the genetic code in arthropod mitochondrial genomes.

    Directory of Open Access Journals (Sweden)

    Federico Abascal

    2006-05-01

    Full Text Available The genetic code provides the translation table necessary to transform the information contained in DNA into the language of proteins. In this table, a correspondence between each codon and each amino acid is established: tRNA is the main adaptor that links the two. Although the genetic code is nearly universal, several variants of this code have been described in a wide range of nuclear and organellar systems, especially in metazoan mitochondria. These variants are generally found by searching for conserved positions that consistently code for a specific alternative amino acid in a new species. We have devised an accurate computational method to automate these comparisons, and have tested it with 626 metazoan mitochondrial genomes. Our results indicate that several arthropods have a new genetic code and translate the codon AGG as lysine instead of serine (as in the invertebrate mitochondrial genetic code or arginine (as in the standard genetic code. We have investigated the evolution of the genetic code in the arthropods and found several events of parallel evolution in which the AGG codon was reassigned between serine and lysine. Our analyses also revealed correlated evolution between the arthropod genetic codes and the tRNA-Lys/-Ser, which show specific point mutations at the anticodons. These rather simple mutations, together with a low usage of the AGG codon, might explain the recurrence of the AGG reassignments.

  9. An evidence-based vector control strategy for military deployments: the British Army experience.

    Science.gov (United States)

    Croft, A M; Baker, D; von Bertele, M J

    2001-01-01

    We describe the British Army's current strategy for controlling arthropod vectors of disease during overseas deployments. Military commanders and medical officers have different, but complementary responsibilities in achieving vector control. In this paper we define a hierarchy of evidence-based vector control guidelines. Field guidelines must be based on the best available research evidence, preferably that derived from pragmatic randomised controlled trials (RCTs), and from systematic reviews of trials. Assessing the effectiveness of different vector control measures involves a trade-off between the relative benefits and harm of different technology options. There is compelling scientific evidence that bed nets and screens treated with a pyrethroid insecticide are highly effective in protecting against nocturnally active, anthropophilic arthropods (including ectoparasites), and will reduce the incidence of malaria, leishmaniasis, lymphatic filariasis and Chagas' disease. Etofenprox and deltamethrin are the safest pyrethroids, and permethrin the least safe. Vector control strategies of probable effectiveness are the use of insecticide-treated clothing, the wearing of protective clothing, and the correct use of DEET-based topical insect repellents. Aerosol insecticides are of debatable effectiveness. Other effective vector control measures, of limited usefulness during deployments, include electric fans, mosquito coils/vaporising mats, and smoke. "Biological" vector control measures, and insect buzzers/electrocuters are ineffective. Practical insect avoidance measures, based on an understanding of vector biology, complete the military vector-control arsenal. We conclude that practical insect avoidance measures, combined with pyrethroid-treated nets and clothing, and DEET-based topical repellents, can achieve almost 100% protection against biting arthropods. PMID:11584666

  10. The i5K Initiative: advancing arthropod genomics for knowledge, human health, agriculture, and the environment.

    Science.gov (United States)

    2013-01-01

    Insects and their arthropod relatives including mites, spiders, and crustaceans play major roles in the world's terrestrial, aquatic, and marine ecosystems. Arthropods compete with humans for food and transmit devastating diseases. They also comprise the most diverse and successful branch of metazoan evolution, with millions of extant species. Here, we describe an international effort to guide arthropod genomic efforts, from species prioritization to methodology and informatics. The 5000 arthropod genomes initiative (i5K) community met formally in 2012 to discuss a roadmap for sequencing and analyzing 5000 high-priority arthropods and is continuing this effort via pilot projects, the development of standard operating procedures, and training of students and career scientists. With university, governmental, and industry support, the i5K Consortium aspires to deliver sequences and analytical tools for each of the arthropod branches and each of the species having beneficial and negative effects on humankind. PMID:23940263

  11. Methodological considerations in discriminating olive-orchard management type using olive-canopy arthropod fauna at the level of order

    Directory of Open Access Journals (Sweden)

    Carlos Jerez-Valle

    2015-12-01

    Full Text Available The cultivation of the olive tree (Olea europaea L. has great importance in the entire Mediterranean basin, so that the implementation of organic practices in their management directly affects the sustainability of the agricultural system. Bioindication with arthropods can help to detect the different agricultural practices. In this work, we analyse the most appropriate methodology for discriminating between management using arthropods at the taxonomic level of order, with the novelty of taking into account the weather conditions to select the sampling dates. Between 12 and 15 sampling stations (depending on the year were selected from olive orchards belonging to organic, conventional non-tillage, and strict conventional management, being sampled by beating the canopy fortnightly in the spring-summer period of 2007, 2008 and 2009. Organic management was more abundant and richer than the rest for the three years. Most groups with significant differences in terms of relative abundance were more abundant in organic orchard, except Neuroptera. Finally, different discriminant methods were evaluated (Linear Discriminant Analysis, Multiple Discriminant Analysis, and Support Vector Machine with several different data sets. The discriminant analysis with interannual variability reached 97.9% accuracy in differentiating between organic and non-organic management using the LDA method, considering the taxa with significant differences from the abundance, excluding pests, and using samples with more uniform and stable weather patterns (late summer.

  12. Insect vector-mediated transmission of plant viruses.

    Science.gov (United States)

    Whitfield, Anna E; Falk, Bryce W; Rotenberg, Dorith

    2015-05-01

    The majority of plant-infecting viruses are transmitted to their host plants by vectors. The interactions between viruses and vector vary in duration and specificity but some common themes in vector transmission have emerged: 1) plant viruses encode structural proteins on the surface of the virion that are essential for transmission, and in some cases additional non-structural helper proteins that act to bridge the virion to the vector binding site; 2) viruses bind to specific sites in or on vectors and are retained there until they are transmitted to their plant hosts; and 3) viral determinants of vector transmission are promising candidates for translational research aimed at disrupting transmission or decreasing vector populations. In this review, we focus on well-characterized insect vector-transmitted viruses in the following genera: Caulimovirus, Crinivirus, Luteovirus, Geminiviridae, Reovirus, Tospovirus, and Tenuivirus. New discoveries regarding these genera have increased our understanding of the basic mechanisms of virus transmission by arthropods, which in turn have enabled the development of innovative strategies for breaking the transmission cycle. PMID:25824478

  13. Plant diversity impacts decomposition and herbivory via changes in aboveground arthropods

    OpenAIRE

    Anne Ebeling; Meyer, Sebastian T.; Maike Abbas; Nico Eisenhauer; Helmut Hillebrand; Markus Lange; Christoph Scherber; Anja Vogel; Alexandra Weigelt; Weisser, Wolfgang W.

    2014-01-01

    Loss of plant diversity influences essential ecosystem processes as aboveground productivity, and can have cascading effects on the arthropod communities in adjacent trophic levels. However, few studies have examined how those changes in arthropod communities can have additional impacts on ecosystem processes caused by them (e.g. pollination, bioturbation, predation, decomposition, herbivory). Therefore, including arthropod effects in predictions of the impact of plant diversity loss on such ...

  14. Spatially selective colonization of the arthropod intestine through activation of Vibrio cholerae biofilm formation

    OpenAIRE

    Purdy, Alexandra E.; Watnick, Paula I.

    2011-01-01

    Vibrio cholerae is an estuarine bacterium and the human pathogen responsible for the diarrheal disease cholera. In the environment, arthropods are proposed to be carriers and reservoirs of V. cholerae. However, the molecular basis of the association between V. cholerae and viable arthropods has not been elucidated previously. Here, we show that the V. cholerae Vibrio polysaccharide (VPS)-dependent biofilm is highly activated upon entry into the arthropod intestine and is specifically required...

  15. RSS (http://www.iaees.org/publications/journals/arthropods/rss.xml

    Directory of Open Access Journals (Sweden)

    Arthropods (ISSN 2224-4255

    Full Text Available Arthropods ISSN 2224-4255 URL: http://www.iaees.org/publications/journals/arthropods/online-version.asp RSS: http://www.iaees.org/publications/journals/arthropods/rss.xml E-mail: arthropods@iaees.org Editor-in-Chief: WenJun Zhang Aims and Scope ARTHROPODS (ISSN 2224-4255 is an international journal devoted to the publication of articles on various aspects of arthropods, e.g., ecology, biogeography, systematics, biodiversity (species diversity, genetic diversity, et al., conservation, control, etc. The journal provides a forum for examining the importance of arthropods in biosphere (both terrestrial and marine ecosystems and human life in such fields as agriculture, forestry, fishery, environmental management and human health. The scope of Arthropods is wide and embraces all arthropods-insects, arachnids, crustaceans, centipedes, millipedes, and other arthropods. Articles/short communications on new taxa (species, genus, families, orders, etc. and new records of arthropods are particularly welcome. Authors can submit their works to the email box of this journal, arthropods@iaees.org. All manuscripts submitted to this journal must be previously unpublished and may not be considered for publication elsewhere at any time during review period of this journal. Authors are asked to read Author Guidelines before submitting manuscripts. In addition to free submissions from authors around the world, special issues are also accepted. The organizer of a special issue can collect submissions (yielded from a research project, a research group, etc. on a specific research topic, or submissions of a scientific conference for publication of special issue.

  16. Vector nematicons

    CERN Document Server

    Horikis, Theodoros P

    2016-01-01

    Families of soliton pairs, namely vector solitons, are found within the context of a coupled nonlocal nonlinear Schrodinger system of equations, as appropriate for modeling beam propagation in nematic liquid crystals. In the focusing case, bright soliton pairs have been found to exist provided their amplitudes satisfy a specific condition. In our analytical approach, focused on the defocusing regime, we rely on a multiscale expansion methods, which reveals the existence of dark-dark and antidark-antidark solitons, obeying an effective Korteweg-de Vries equation, as well as dark-bright solitons, obeying an effective Mel'nikov system. These pairs are discriminated by the sign of a constant that links all physical parameters of the system to the amplitude of the stable continuous wave solutions, and, much like the focusing case, the solitons' amplitudes are linked leading to mutual guiding.

  17. Canopy arthropods community within and among oak species in central Mexico

    Institute of Scientific and Technical Information of China (English)

    Efraín TOVAR-SANCHEZ

    2009-01-01

    Quercus rugosa and Q.laurina are species that presents a wide geographical distribution range in temperate forests of Mexico. Oak canopies contain a considerable portion of arthropod diversity and the arthropods fauna fulfill a wide variety of ecological roles. We examined the effect of oak species and seasonal changes on some community structure parameters (diversity, composition, similarity, biomass, rare species, and density of arthropod fauna) of canopy arthropods. In total, 40 oak canopies were fogged during rainy and dry season. A total of 614 identified arthropod morphospecies were recognized belonging to 22 orders associated with tree canopies. A separation of host tree species during both seasons, suggesting a different community structure on host plants species was demonstrated by the principal component analyses (PCA), therefore, differences between oak species results in phenotypes that structure the composition of the arthropod community. Q.laurina registered the highest densities, diversity index and number of rare species in comparison with Q.rugosa. While arthropod biomass showed an inverse pattern. Trees more close to one another (spatial distance) register a more similar canopy arthropod fauna. This study suggests that the trees of Q.laurina could act as a center of biodiversity by the accumulation of arthropod fauna with a considerable number of rare species, which presents wide ecological roles or is involved in critical processes that maintain forest ecosystems[Current Zoology 55(2):132-144,2009].

  18. Arthropods of the great indoorssuburban homes:characterizing diversity inside urban and suburban homes

    OpenAIRE

    Bertone, Matthew A.; Leong, Misha; Bayless, Keith M.; Malow, Tara L.F.; Dunn, Robert Roberdeau; Trautwein, Michelle D.

    2016-01-01

    Although humans and arthropods have been living and evolving together for all of our history, we know very little about the arthropods we share our homes with apart from major pest groups. Here we surveyed, for the first time, the complete arthropod fauna of the indoor biome in 50 houses (located in and around Raleigh, North Carolina, USA). We discovered high diversity, with a conservative estimate range of 32–211 morphospecies, and 24–128 distinct arthropod families per house. The majority o...

  19. Climate variability and change in the United States: potential impacts on vector- and rodent-borne diseases.

    OpenAIRE

    Gubler, D J; Reiter, P.; Ebi, K L; Yap, W; Nasci, R; Patz, J.A.

    2001-01-01

    Diseases such as plague, typhus, malaria, yellow fever, and dengue fever, transmitted between humans by blood-feeding arthropods, were once common in the United States. Many of these diseases are no longer present, mainly because of changes in land use, agricultural methods, residential patterns, human behavior, and vector control. However, diseases that may be transmitted to humans from wild birds or mammals (zoonoses) continue to circulate in nature in many parts of the country. Most vector...

  20. Distribution of arthropods in rice grains in Malaysia

    Institute of Scientific and Technical Information of China (English)

    Mariana A; Ho TM; Lau TY; Heah SK; Wong AL

    2009-01-01

    Objective:To determine distribution of arthropods in rice grains obtained from different sources.Methods:Rice samples were randomly collected from public in urban areas,farmers in rice field areas,aborigines in un-developed areas and retailers in commercial premises.Random samples of rice were taken out from each sam-ple for isolation of arthropods using a modified Berlese Tullgren Funnel Method.Mites were mounted prior to i-dentification;weevils were directly identified.Results:Samples of rice from retailers in commercial premises had the highest infestation by arthropods followed by samples from urbanites,aborigines and rice farmers.Two species of weevils,Sitophilus oryzae(S.oryzae)and Sitophilus granarius(S.granarius),were found.Samples from commercial premises had the least percentage of weevils compared to those collected from domestic premi-ses.Depending on the source of samples,densities of S.granarius and S.oryzae ranges from 1 1 -1 03 weevils? kg and 7-80 weevils?kg,respectively.Important species of mites in stored rice identified were mainly members of the families Cheyletidae,Echimyopodidae,Pyroglyphidae,Saproglyphidae and Tenuipalpidae.Among the species of mites identified were Austroglycyphagus malaysiensis,Cheyletus fortis,Cheyletus malaccensis,Der-matophagoides pteronyssinus,Grammolichus malukuensis and Suidasia pontifica.Average density of most of the mites was less than 40 mites?kg of rice grains.In this study,the highest number of mites in rice samples was recovered from commercial premises,followed by samples from urbanites.Samples from farmers and aborigines contained lesser mites.Conclusion:This study demonstrated the presence of 3 allergenic mite species in rice, i.e A.malaysiensis,D.pteronyssinus and S.pontifica.Weevils,S.oryzae and S.granarius that are known to be allergenic,were also found.

  1. cuticleDB: a relational database of Arthropod cuticular proteins

    Directory of Open Access Journals (Sweden)

    Willis Judith H

    2004-09-01

    Full Text Available Abstract Background The insect exoskeleton or cuticle is a bi-partite composite of proteins and chitin that provides protective, skeletal and structural functions. Little information is available about the molecular structure of this important complex that exhibits a helicoidal architecture. Scores of sequences of cuticular proteins have been obtained from direct protein sequencing, from cDNAs, and from genomic analyses. Most of these cuticular protein sequences contain motifs found only in arthropod proteins. Description cuticleDB is a relational database containing all structural proteins of Arthropod cuticle identified to date. Many come from direct sequencing of proteins isolated from cuticle and from sequences from cDNAs that share common features with these authentic cuticular proteins. It also includes proteins from the Drosophila melanogaster and the Anopheles gambiae genomes, that have been predicted to be cuticular proteins, based on a Pfam motif (PF00379 responsible for chitin binding in Arthropod cuticle. The total number of the database entries is 445: 370 derive from insects, 60 from Crustacea and 15 from Chelicerata. The database can be accessed from our web server at http://bioinformatics.biol.uoa.gr/cuticleDB. Conclusions CuticleDB was primarily designed to contain correct and full annotation of cuticular protein data. The database will be of help to future genome annotators. Users will be able to test hypotheses for the existence of known and also of yet unknown motifs in cuticular proteins. An analysis of motifs may contribute to understanding how proteins contribute to the physical properties of cuticle as well as to the precise nature of their interaction with chitin.

  2. The Insect Microbiome Modulates Vector Competence for Arboviruses

    Directory of Open Access Journals (Sweden)

    Natapong Jupatanakul

    2014-11-01

    Full Text Available Diseases caused by arthropod-borne viruses (arboviruses, such as Dengue, West Nile, and Chikungunya, constitute a major global health burden and are increasing in incidence and geographic range. The natural microbiota of insect vectors influences various aspects of host biology, such as nutrition, reproduction, metabolism, and immunity, and recent studies have highlighted the ability of insect-associated bacteria to reduce vector competence for arboviruses and other pathogens. This reduction can occur through mechanisms, such as immune response activation, resource competition, or the production of anti-viral molecules. Studying the interactions between insect vectors and their microbiota is an important step toward developing alternative strategies for arbovirus transmission control.

  3. Impacts of major predators on tropical agroforest arthropods: comparisons within and across taxa.

    Science.gov (United States)

    Philpott, Stacy M; Greenberg, Russell; Bichier, Peter; Perfecto, Ivette

    2004-06-01

    In food web studies, taxonomically unrelated predators are often grouped into trophic levels regardless of their relative importance on prey assemblages, multiple predator effects, or interactions such as omnivory. Ants and birds are important predators likely to differentially shape arthropod assemblages, but no studies have compared their effects on a shared prey base. In two separate studies, we excluded birds and ants from branches of a canopy tree ( Inga micheliana) in a coffee farm in Mexico for 2 months in the dry and wet seasons of 2002. We investigated changes in arthropod densities with and without predation pressure from (1) birds and (2) ant assemblages dominated by one of two ant species ( Azteca instabilis and Camponotus senex). We first analyzed individual effects of each predator (birds, Azteca instabilis, and C. senex) then used a per day effect metric to compare differences in effects across (birds vs ants) and within predator taxa (the two ant species). Individually, birds reduced densities of total and large arthropods and some arthropod orders (e.g., spiders, beetles, roaches) in both seasons. Azteca instabilis did not significantly affect arthropods (total, small, large or specific orders). Camponotus senex, however, tended to remove arthropods (total, small), especially in the dry season, and affected arthropod densities of some orders both positively and negatively. Predators greatly differed in their effects on Inga arthropods (for all, small, large, and individual orders of arthropods) both in sign (+/-) and magnitudes of effects. Birds had stronger negative effects on arthropods than ants and the two dominant ant species had stronger effects on arthropods in different seasons. Our results show that aggregating taxonomically related and unrelated predators into trophic levels without prior experimental data quantifying the sign and strengths of effects may lead to a misrepresentation of food web interactions. PMID:15095089

  4. Interactions among predators and the cascading effects of vertebrate insectivores on arthropod communities and plants.

    Science.gov (United States)

    Mooney, Kailen A; Gruner, Daniel S; Barber, Nicholas A; Van Bael, Sunshine A; Philpott, Stacy M; Greenberg, Russell

    2010-04-20

    Theory on trophic interactions predicts that predators increase plant biomass by feeding on herbivores, an indirect interaction called a trophic cascade. Theory also predicts that predators feeding on predators, or intraguild predation, will weaken trophic cascades. Although past syntheses have confirmed cascading effects of terrestrial arthropod predators, we lack a comprehensive analysis for vertebrate insectivores-which by virtue of their body size and feeding habits are often top predators in these systems-and of how intraguild predation mediates trophic cascade strength. We report here on a meta-analysis of 113 experiments documenting the effects of insectivorous birds, bats, or lizards on predaceous arthropods, herbivorous arthropods, and plants. Although vertebrate insectivores fed as intraguild predators, strongly reducing predaceous arthropods (38%), they nevertheless suppressed herbivores (39%), indirectly reduced plant damage (40%), and increased plant biomass (14%). Furthermore, effects of vertebrate insectivores on predatory and herbivorous arthropods were positively correlated. Effects were strongest on arthropods and plants in communities with abundant predaceous arthropods and strong intraguild predation, but weak in communities depauperate in arthropod predators and intraguild predation. The naturally occurring ratio of arthropod predators relative to herbivores varied tremendously among the studied communities, and the skew to predators increased with site primary productivity and in trees relative to shrubs. Although intraguild predation among arthropod predators has been shown to weaken herbivore suppression, we find this paradigm does not extend to vertebrate insectivores in these communities. Instead, vertebrate intraguild preda-tion is associated with strengthened trophic cascades, and insectivores function as dominant predators in terrestrial plant-arthropod communities. PMID:20368418

  5. Genetic variation in functional traits influences arthropod community composition in aspen (Populus tremula L.).

    Science.gov (United States)

    Robinson, Kathryn M; Ingvarsson, Pär K; Jansson, Stefan; Albrectsen, Benedicte R

    2012-01-01

    We conducted a study of natural variation in functional leaf traits and herbivory in 116 clones of European aspen, Populus tremula L., the Swedish Aspen (SwAsp) collection, originating from ten degrees of latitude across Sweden and grown in a common garden. In surveys of phytophagous arthropods over two years, we found the aspen canopy supports nearly 100 morphospecies. We identified significant broad-sense heritability of plant functional traits, basic plant defence chemistry, and arthropod community traits. The majority of arthropods were specialists, those coevolved with P. tremula to tolerate and even utilize leaf defence compounds. Arthropod abundance and richness were more closely related to plant growth rates than general chemical defences and relationships were identified between the arthropod community and stem growth, leaf and petiole morphology, anthocyanins, and condensed tannins. Heritable genetic variation in plant traits in young aspen was found to structure arthropod community; however no single trait drives the preferences of arthropod folivores among young aspen genotypes. The influence of natural variation in plant traits on the arthropod community indicates the importance of maintaining genetic variation in wild trees as keystone species for biodiversity. It further suggests that aspen can be a resource for the study of mechanisms of natural resistance to herbivores.

  6. Genetic variation in functional traits influences arthropod community composition in aspen (Populus tremula L..

    Directory of Open Access Journals (Sweden)

    Kathryn M Robinson

    Full Text Available We conducted a study of natural variation in functional leaf traits and herbivory in 116 clones of European aspen, Populus tremula L., the Swedish Aspen (SwAsp collection, originating from ten degrees of latitude across Sweden and grown in a common garden. In surveys of phytophagous arthropods over two years, we found the aspen canopy supports nearly 100 morphospecies. We identified significant broad-sense heritability of plant functional traits, basic plant defence chemistry, and arthropod community traits. The majority of arthropods were specialists, those coevolved with P. tremula to tolerate and even utilize leaf defence compounds. Arthropod abundance and richness were more closely related to plant growth rates than general chemical defences and relationships were identified between the arthropod community and stem growth, leaf and petiole morphology, anthocyanins, and condensed tannins. Heritable genetic variation in plant traits in young aspen was found to structure arthropod community; however no single trait drives the preferences of arthropod folivores among young aspen genotypes. The influence of natural variation in plant traits on the arthropod community indicates the importance of maintaining genetic variation in wild trees as keystone species for biodiversity. It further suggests that aspen can be a resource for the study of mechanisms of natural resistance to herbivores.

  7. Modification and application of a leaf blower-vac for field sampling of arthropods

    NARCIS (Netherlands)

    Zou, Yi; Telgen, van Mario D.; Chen, Junhui; Xiao, Haijun; Kraker, de Joop; Bianchi, Felix J.J.A.; Werf, van der Wopke

    2016-01-01

    Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure,

  8. Effects of weed harrowing frequency on beneficial arthropods, plants and crop yield

    DEFF Research Database (Denmark)

    Navntoft, Søren; Kristensen, Kristian; Johnsen, Ib;

    2016-01-01

    * Weed harrowing is an alternative to herbicides but it may have negative effects on epigaeic arthropods. We assessed the effects of frequent (four) versus two harrowings during the growing season on the density and diversity of generalist arthropods and the weed flora. Collection by flooding was...

  9. "Bugs on Bugs": An Inquiry-Based, Collaborative Activity to Learn Arthropod & Microbial Biodiversity

    Science.gov (United States)

    Lampert, Evan C.; Morgan, Jeanelle M.

    2015-01-01

    Diverse communities of arthropods and microbes provide humans with essential ecosystem goods and services. Arthropods are the most diverse and abundant macroscopic animals on the planet, and many remain to be discovered. Much less is known about microbial diversity, despite their importance as free-living species and as symbionts. We created…

  10. Arthropods in no-tillage soybean agroecosystems: Community composition and ecosystem interactions

    Science.gov (United States)

    House, Garfield J.; Stinner, Benjamin R.

    1983-01-01

    Sampling data are provided and concepts discussed regarding soil and foliage arthropod communities in conventional and no-tillage soybean agroecosystems Soil arthropod communities from the two cropping systems were also compared with that from an adjacent old field. Biweekly arthropod samples were collected from conventional, no-tillage, and old-field systems Soil arthropods were sampled by quadrat and pitfall trap methods, foliage arthropods were collected by sweep net Quadrat sampling revealed that ground beetle number, species diversity, and biomass were significantly higher ( Ptrap data indicated higher densities and species diversity for most major soil macro-arthropod guilds Foliage arthropod guilds from no-tillage treatments showed higher species diversity throughout the growing season than those of conventional tillage, possibly because of greater structural diversity provided by weeds and litter in notillage systems No-tillage systems supported a larger and more diverse arthropod community than conventionally grown soybeans, suggesting a need for pest management strategies that simultaneously consider many variables. Both foliar grazing and leaf nitrogen content were higher in conventional than in no-tillage systems, indicating a possible causal connection between soil tillage and insect herbivory rates

  11. Composition and Diversity of Soil Arthropods of Rajegwesi Meru Betiri National Park

    Directory of Open Access Journals (Sweden)

    Hasan Zayadi

    2013-09-01

    Full Text Available Meru Betiri National Park (MBNP is one of the nature conservation area that has the potential of flora, fauna, and ecosystems that could develop as a nature-based tourism attraction. The existence of certain indicator species was related to estimation of stress level and disturbance on ecosystem stability for making strategic decisions about the restoration in this area. One of the important indicator species at forest ecosystem were soil arthropods. Aim this research were analyzed composition and diversity of soil arthropods at Rajegwesi, MBNP areas. The methods in this research used pitfall trap, measurement of distribution structure and soil arthropods composition based on the Shannon - Wiener index, Morisita similarity index and Importance Value Index (IVI. The number of families and individuals of soil arthropods found in the coastal area of Rajegwesi consists of 10 order with 21 families (702 individual. The number of individuals of the order Hymenoptera, Coleoptera, Collembola and Araneida was more widely found. Soil arthropods diversity index on each land use indicated that soil arthropod diversity in these areas were moderate. Soil arthropod community of orchards and forest had a similarity of species composition, whereas soil arthropod community of savanna had a similarity of species composition with paddy fields.

  12. The importance of arthropod pests in Belgian pome fruit orchards.

    Science.gov (United States)

    Bangels, Eva; De Schaetzen, Charles; Hayen, Guy; Paternotte, Edouard; Gobin, Bruno

    2008-01-01

    Located in temperate, maritime climate with frequent rainfall, crop protection in Belgian orchards is dominated by fungicides. Though, the importance of arthropod pests should not be underestimated. Pcfruit, the former Research station of Gorsem, has been maintaining a warning system for fruit pests in Belgium since 1944. Therefore, various pests and beneficial's and their life cycle stages have been monitored in Gorsem and in different observation posts across Belgium, being part of a monitoring network. Although up to 3000 arthropod species are present in pome fruit orchards, about 25% can be considered as harmful and another 25% as beneficial. Out of those species, around 100 harmful and 50 beneficial organisms are omnipresent. The list of monitored species is extended yearly for upcoming or difficult to control organisms. Integrated pest management was introduced in the eighties, with the accent on using selective pesticides and saving beneficial organisms. A shift in pesticide use affected the importance of secondary pests, together with recent exceptional climatic conditions. Following many years of monitoring insects and mites and editing warning bulletins in our station, a ranking of the economical importance of different pest species is presented.

  13. Character combinations, convergence and diversification in ectoparasitic arthropods.

    Science.gov (United States)

    Poulin, Robert

    2009-08-01

    Different lineages of organisms diversify over time at different rates, in part as a consequence of the characteristics of the species in these lineages. Certain suites of traits possessed by species within a clade may determine rates of diversification, with some particular combinations of characters acting synergistically to either limit or promote diversification; the most successful combinations may also emerge repeatedly in different clades via convergent evolution. Here, the association between species characters and diversification is investigated amongst 21 independent lineages of arthropods ectoparasitic on vertebrate hosts. Using nine characters (each with two to four states) that capture general life history strategy, transmission mode and host-parasite interaction, each lineage was described by the set of character states it possesses. The results show, firstly, that most possible pair-wise combinations of character states have been adopted at least once, sometimes several times independently by different lineages; thus, ectoparasitic arthropods have explored most of the life history character space available to them. Secondly, lineages possessing commonly observed combinations of character states are not necessarily the ones that have experienced the highest rates of diversification (measured as a clade's species-per-genus ratio). Thirdly, some specific traits are associated with higher rates of diversification. Using more than one host per generation, laying eggs away from the host and intermediate levels of fecundity are features that appear to have promoted diversification. These findings indicate that particular species characters may be evolutionary drivers of diversity, whose effects could also apply in other taxa.

  14. Behaviour of filariae: morphological and anatomical signatures of their life style within the arthropod and vertebrate hosts.

    Science.gov (United States)

    Bain, Odile; Babayan, Simon

    2003-12-15

    This paper attempts to pinpoint the most original morphological anatomical features of the biology of filariae per se and those which are or could be important for triggering regulatory processes in the arthropod vector and uncontrolled pathogenic processes in the vertebrate hosts. The following stages are considered: the motile egg or newly-hatched larva, the microfilaria, in the lymphatic or blood vessels of its vertebrate host; the larva, its migrations and its intrasyncitial development in the hematophagous arthropod subverted as vector; its transfer to the vertebrate host, migratory properties through the lymphatic system, maturation, mating and, finally, egg laying in the tissues they reach. This synthesis is based on parasite morphological features and their functional interpretation, histological features in the different niches the filariae reach, and on quantitative analyses of filarial development at its different phases, as well as on the rare and valuable observations of living parasites in situ. Data have been drawn from various species of Onchocercidae from amphibians, reptiles, birds and mammals. These comparative analyses have revealed the major constraints to which the filariae, including those parasitizing humans, have been subjected during their evolution from their ancestors, the oviparous and heteroxenic spirurids. Emphasis is placed on mechanical events: resistance of the microfilariae to the currents in the blood or lymph vessels, regulatory processes induced in the vector mesenteron by the movements of the ingested microfilariae, transient disruption by the microfilarial cephalic hook of the vectors' tissues and cell membranes during microfilarial translocation, attachment of males to females during mating by means of 'non-slip' systems, etc. Like other nematodes, filariae are equipped with sensory organs and a locomotor system, composed of the muscles and of the original osmoregulatory-excretory cell. Any change in one of these elements

  15. Arthropod succession on pig carcasses in southeastern Nigeria

    Directory of Open Access Journals (Sweden)

    M.S. Ekanem

    2010-01-01

    Full Text Available The domestic pig (Sus scrofa was used as a model to study arthropod succession on carcasses under tree shade and out of shade in southern Nigeria. Carcass decomposition took longer periods under tree shade than in exposed sites, at 24.5 and 16.5 days, respectively. Four decomposition stages - fresh, bloated, decay, and dry - were observed. No significant variabilities were recorded in the types and patterns of infestation of the carcasses by arthropods in both locations. Four classes of arthropods - Insecta, Arachnida, Diplopoda and Crustacea - were recorded. The class Insecta dominated the total arthropods collected with 24 families, and formed 94% of the catches. The other three classes each had one family represented, and contributed only 2% of the total catches. The calliphorids, a phorid, and sarcophagids arrived and bred on the carcasses only a few hours after death of the pigs. Families of coleopterans came during the bloated stage, and fed on the immature dipterous maggots and carrion materials. The ants (Hymenoptera came in large numbers to eat the carcasses, and also preyed on all other fauna of the food resource. A muscid and a stratiomyiid, bred on the carcass as to the decay stage. Other insects and arthropods arrived mostly during the decay stage to feed on the carcasses. Species richness on the carcasses peaked during the decay stage.O porco branco (Sus scrofa foi usado como modelo para o estudo da sucessão de Artrópodes em cadáveres em zonas sombreadas e não sombreadas por árvores no sul da Nigéria. Nos cadáveres em decomposição em zonas sombreadas observou-se um processo de decomposição mais lento que nos expostos ao sol; 24,5 e 16,5 dias, respectivamente. Foram observadas quatro etapas de decomposição; fresco (autólise, intumescido (putrefação, deteriorado e seco (diagênese. Não foram observadas diferenças significativas de tipo e padrão nas infestações dos cadáveres por Artrópodes em ambas as condi

  16. Future rainfall variations reduce abundances of aboveground arthropods in model agroecosystems with different soil types

    Directory of Open Access Journals (Sweden)

    Johann G. Zaller

    2014-10-01

    Full Text Available Climate change scenarios for Central Europe predict less frequent but heavier rainfalls and longer drought periods during the growing season. This is expected to alter arthropods in agroecosystems that are important as biocontrol agents, herbivores or food for predators (e.g. farmland birds. In a lysimeter facility (totally 18 3-m2-plots, we experimentally tested the effects of long-term past vs. prognosticated future rainfall variations (15% increased rainfall per event, 25% more dry days according to regionalized climate change models from the Intergovernmental Panel on Climate Change (IPCC on aboveground arthropods in winter wheat (Triticum aestivum L. cultivated at three different soil types (calcaric phaeozem, calcic chernozem and gleyic phaeozem. Soil types were established 17 years and rainfall treatments one month before arthropod sampling; treatments were fully crossed and replicated three times. Aboveground arthropods were assessed by suction sampling, their mean abundances (± SD differed between April, May and June with 20 ± 3 m-2, 90 ± 35 m-2 and 289 ± 93 individuals m-2, respectively. Averaged across sampling dates, future rainfall reduced the abundance of spiders (Araneae, -47%, cicadas and leafhoppers (Auchenorrhyncha, -39%, beetles (Coleoptera, -52%, ground beetles (Carabidae, -41%, leaf beetles (Chrysomelidae, -64%, spring tails (Collembola, -58%, flies (Diptera, -73% and lacewings (Neuroptera, -73% but increased the abundance of snails (Gastropoda, +69%. Across sampling dates, soil types had no effects on arthropod abundances. Arthropod diversity was neither affected by rainfall nor soil types. Arthropod abundance was positively correlated with weed biomass for almost all taxa; abundance of Hemiptera and of total arthropods was positively correlated with weed density. These detrimental effects of future rainfall varieties on arthropod taxa in wheat fields can potentially alter arthropod-associated agroecosystem services.

  17. Herbivore-induced plant volatiles as a rich source of information for arthropod predators: fundamental and applied aspects

    NARCIS (Netherlands)

    Dicke, M.

    2015-01-01

    Plants respond to arthropod herbivory with the induction of volatiles that attract predatory arthropods that attack the herbivores. These so-called herbivore-induced plant volatiles (HIPVs) appear to be important sources of information that mediate many interactions within a plant–arthropod communit

  18. Rotations with Rodrigues' Vector

    Science.gov (United States)

    Pina, E.

    2011-01-01

    The rotational dynamics was studied from the point of view of Rodrigues' vector. This vector is defined here by its connection with other forms of parametrization of the rotation matrix. The rotation matrix was expressed in terms of this vector. The angular velocity was computed using the components of Rodrigues' vector as coordinates. It appears…

  19. Foraging range of arthropods with veterinary interest: New insights for Afrotropical Culicoides biting midges (Diptera: Ceratopogonidae) using the ring method.

    Science.gov (United States)

    Bakhoum, M T; Fall, M; Seck, M T; Gardès, L; Fall, A G; Diop, M; Mall, I; Balenghien, T; Baldet, T; Gimonneau, G; Garros, C; Bouyer, J

    2016-05-01

    The identification of blood meal source of arthropod vector species contributes to the understanding of host-vector-pathogen interactions. The aim of the current work was to identify blood meal source in Culicoides biting midge species, biological vectors of internationally important arboviruses of livestock and equids, using a new ecological approach. We examined the correlation between blood meal source identified in engorged Culicoides females collected in a suction light trap and the available vertebrate hosts along four rings (200, 500, 1000 and 2000 m) centered at the trap site and described the foraging range of the three main vector species of veterinary interest present in the study area, Culicoides imicola, Culicoides kingi and Culicoides oxystoma. The study was performed in four sites localized in the Niayes region of Senegal (West Africa) where recent outbreaks of African horse sickness occurred. Blood meal source identification was carried out by species-specific multiplex PCRs with genomic DNA extracted from the abdomen of engorged females collected during nine night collections for twenty-six collections. The four most abundant hosts present in the studied area (horse, cattle, goat and sheep) were surveyed in each ring zone. The blood meal source varied according to Culicoides species and host availability in each site. C. oxystoma and C. imicola females mainly fed on horses readily available at 200 m maximum from the trap location whereas females of C. kingi fed mainly on cattle, at variable distances from the traps (200 to 2000 m). C. oxystoma may also feed on other vertebrates. We discuss the results in relation with the transmission of Culicoides-borne arboviruses and the species dispersion capacities. PMID:26826391

  20. Bacteria, fungi and arthropod pests collected on modern human mummies

    Directory of Open Access Journals (Sweden)

    F. Palla

    2011-08-01

    Full Text Available A survey of opportunistic biocenosis (macro and micro organisms associated with a rest of human mummy samples was carried out to characterise the biocenosis and to detect the potential of biodeteriogens. The rests of the human modern mummies come from a hypogeic site. Since mummies are relevant from a historic-artistic-scientific point of view, an aspect of this study was the identification and characterization of the biological systems related with biodeterioration of organic matter. In a first step, different sampling methods, according to the taxa, were applied. Technological procedures were combined in order to have an interdisciplinary approach to the conservation actions for testing future restoration protocols. Specimens were collected, identified and characterized by Microscopy (light, SEM, CLSM and molecular analyses (DNA extraction, in vitro target sequence amplification, sequencing, sequence analysis. The results highlight a rather complex biocenonsis consisting of fungi, cyanobacteria, several insects and other arthropods.

  1. Green-synthesized silver nanoparticles as a novel control tool against dengue virus (DEN-2) and its primary vector Aedes aegypti

    Science.gov (United States)

    Dengue is an arthropod-borne viral infection mainly vectored through the bite of Aedes mosquitoes. Recently, its transmission has strongly increased in urban and semi-urban areas of tropical and sub-tropical regions worldwide, becoming a major international public health concern. There is no specifi...

  2. Comparison of Arthropod Prey of Red-Cockaded Woodpeckers on the Boles of Longleaf and Loblolly Pines

    Energy Technology Data Exchange (ETDEWEB)

    Horn, S.; Hanula, J.

    2002-01-01

    Use of knockdown insecticides to sample arthropods on longleaf and loblolly pine to determine which harbored the greater abundance of potential prey. Alterations of longleaf pine bark surface to determine whether bark structure may affect arthropods residing on a tree's bole. Recovery revealed fewer arthropods from scraped trees. Results suggest the bark structure and not the chemical nature of the bark is responsible for differences in arthropod abundance and biomass. Retaining or restoring longleaf pine in red-cockaded woodpecker habitats should increase arthropod availability for this endangered bird and other back-foraging species.

  3. Phenoptosis in arthropods and immortality of social insects.

    Science.gov (United States)

    Kartsev, V M

    2014-10-01

    In general, there are no drastic differences in phenoptosis patterns in plant and animal organisms. However, there are some specific features characteristic for insects and other arthropods: 1) their development includes metamorphosis with different biochemical laws at consecutive developmental stages; 2) arthropods can reduce or stop development and aging when in a state of diapause or temporal cold immobility; 3) their life cycle often correlates with seasonal changes of surroundings; 4) polymorphism is widespread - conspecifics differ by their lifespans and phenoptosis features; 5) lifespan-related sexual dimorphism is common; 6) significant situational plasticity of life cycle organization is an important feature; for example, the German wasp (Paravespula germanica) is obligatorily univoltine in the temperate zone, while in tropical regions its lifespan increases and leads to repeated reproduction; 7) life cycles of closely related species may differ significantly, for example, in contrast to German wasp, some tropical hornets (Vespa) have only one reproduction period. Surprisingly, many insect species have been shown to be subjected to gradual aging and phenoptosis, like the highest mammals. However, queens of social insects and some long-lived arachnids can apparently be considered non-aging organisms. In some species, lifespan is limited to one season, while others live much longer or shorter. Cases of one-time reproduction are rather rare. Aphagia is common in insects (over 10,000 species). Cannibalism is an important mortality factor in insects as well as in spiders. In social insects, which exist only in colonies (families), the lifetime of a colony can be virtually unlimited. However, in case of some species the developmental cycle and death of a colony after its completion are predetermined. Most likely, natural selection in insects does not lengthen individual lifespan, but favors increase in reproduction efficiency based on fast succession of

  4. Phenoptosis in arthropods and immortality of social insects.

    Science.gov (United States)

    Kartsev, V M

    2014-10-01

    In general, there are no drastic differences in phenoptosis patterns in plant and animal organisms. However, there are some specific features characteristic for insects and other arthropods: 1) their development includes metamorphosis with different biochemical laws at consecutive developmental stages; 2) arthropods can reduce or stop development and aging when in a state of diapause or temporal cold immobility; 3) their life cycle often correlates with seasonal changes of surroundings; 4) polymorphism is widespread - conspecifics differ by their lifespans and phenoptosis features; 5) lifespan-related sexual dimorphism is common; 6) significant situational plasticity of life cycle organization is an important feature; for example, the German wasp (Paravespula germanica) is obligatorily univoltine in the temperate zone, while in tropical regions its lifespan increases and leads to repeated reproduction; 7) life cycles of closely related species may differ significantly, for example, in contrast to German wasp, some tropical hornets (Vespa) have only one reproduction period. Surprisingly, many insect species have been shown to be subjected to gradual aging and phenoptosis, like the highest mammals. However, queens of social insects and some long-lived arachnids can apparently be considered non-aging organisms. In some species, lifespan is limited to one season, while others live much longer or shorter. Cases of one-time reproduction are rather rare. Aphagia is common in insects (over 10,000 species). Cannibalism is an important mortality factor in insects as well as in spiders. In social insects, which exist only in colonies (families), the lifetime of a colony can be virtually unlimited. However, in case of some species the developmental cycle and death of a colony after its completion are predetermined. Most likely, natural selection in insects does not lengthen individual lifespan, but favors increase in reproduction efficiency based on fast succession of

  5. New insights on arthropod toxins that potentiate erectile function.

    Science.gov (United States)

    Nunes, Kenia P; Torres, Fernanda S; Borges, Marcia H; Matavel, Alessandra; Pimenta, Adriano M C; De Lima, Maria E

    2013-07-01

    The use of natural substances for the treatment of diseases or injuries is an ancient practice of many cultures. According to folklore, natural aphrodisiacs may help to raise libido and increase desire. The supposed aphrodisiacs mainly include a plethora of preparations of plants, among other substances. However, the real boundary between myth and reality has not been established yet in most cases and such boundaries must be drawn by scientific methods. A growing interest of the scientific community has been focused on animal venoms, especially those from arthropods, i.e. spiders and scorpions, which cause priapism, a prolonged and painful erection. This review highlights the studies that have been performed with venoms and toxins from arthropods known to cause priapism, among other toxic symptoms, pointing out some pharmacological approaches for better understanding this effect. To date, the venom of some spiders, mainly Phoneutria nigriventer, and scorpions, such as the yellow South American scorpion Tityus serrulatus, among others, have been known to cause priapism. Since erectile dysfunction (ED) is a growing health problem in the world, more common in patients with vascular diseases as diabetes and hypertension, the use of animal venoms and toxins as pharmacological tools could not only shed light to the mechanisms involved in erectile function, but also represent a possible model for new drugs to treat ED. Unfortunately, attempts to correlate the structure of those priapism-related toxins were unfruitful. Such difficulties lie firstly on the poor data concerning purified priapism-related toxins, instead of whole venoms and/or semi-purified fractions, and secondly, on the scarce available primary sequences and structural data, mainly from spider toxins. It has been shown that all these toxins modify the sodium (Na(+)) channel activity, mostly slowing down its inactivation current. Improving the knowledge on the tertiary structure of these toxins could provide

  6. A systematic review of arthropod community diversity in association with invasive plants

    Directory of Open Access Journals (Sweden)

    Ryan Spafford

    2013-04-01

    Full Text Available Invasive plants represent a significant financial burden for land managers and also have the potential to severely degrade ecosystems. Arthropods interact strongly with plants, relying on them for food, shelter, and as nurseries for their young. For these reasons, the impacts of plant invasions are likely strongly reflected by arthropod community dynamics including diversity and abundances. A systematic review was conducted to ascertain the state of the literature with respect to plant invaders and their associated arthropod communities. We found that the majority of studies did not biogeographically contrast arthropod community dynamics from both the home and away ranges and that studies were typically narrow in scope, focusing only on the herbivore feeding guild, rather than assessing two or more trophic levels. Importantly, relative arthropod richness was significantly reduced on invasive plant species. Phylogenetic differences between the invasive and local plant community as well as the plant functional group impact arthropod diversity patterns. A framework highlighting some interaction mechanisms between multiple arthropod trophic levels and native and invasive plants is discussed and future research directions relating to these interactions and the findings herein are proposed.

  7. Arthropod abundance and seasonal bird use of bottomland forest harvest gaps.

    Energy Technology Data Exchange (ETDEWEB)

    Moorman, Christopher, E.; Bowen, Liessa T.; Kilgo, John, C.; Hanula, James, L.; Horn, Scott; Ulyshen, Michael, D.

    2012-03-01

    We investigated the influence of arthropod abundance and vegetation structure on shifts in avian use of canopy gap, gap edge, and surrounding forest understory in a bottomland hardwood forest in the Upper Coastal Plain of South Carolina. We compared captures of foliage-gleaning birds among locations during four periods (spring migration, breeding, post-breeding, and fall migration). Foliage arthropod densities were greatest in the forest understory in all four seasons, but understory vegetation density was greatest in gaps. Foliage-gleaning bird abundance was positively associated with foliage-dwelling arthropods during the breeding (F = 18.5, P < 0.001) and post-breeding periods (F = 9.4, P = 0.004), and negatively associated with foliage-dwelling arthropods during fall migration (F = 5.4, P = 0.03). Relationships between birds and arthropods were inconsistent, but the arthropod prey base seemed to be least important during migratory periods. Conversely, bird captures were positively correlated with understory vegetation density during all four periods (P < 0.001). Our study suggests high bird abundance associated with canopy gaps during the non-breeding period resulted less from high arthropod food resource availability than from complex understory and midstory vegetation structure.

  8. Acquisition of Cry1Ac protein by non-target arthropods in Bt soybean fields.

    Science.gov (United States)

    Yu, Huilin; Romeis, Jörg; Li, Yunhe; Li, Xiangju; Wu, Kongming

    2014-01-01

    Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults) and sampling dates (before, during, and after flowering). Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean.

  9. Effects of persistent insecticides on beneficial soil arthropod in conventional fields compared to organic fields, puducherry.

    Science.gov (United States)

    Anbarashan, Padmavathy; Gopalswamy, Poyyamoli

    2013-07-15

    The usage of synthetic fertilizers/insecticides in conventional farming has dramatically increased over the past decades. The aim of the study was to compare the effects of bio-pesticides and insecticides/pesticides on selected beneficial non targeted arthropods. Orders Collembola, Arachinida/Opiliones, Oribatida and Coleoptera were the main groups of arthropods found in the organic fields and Coleoptera, Oribatida, Gamasida and Collembola in conventional fields. Pesticides/insecticides had a significant effect on non-targeted arthropods order- Collembola, Arachinida/Opiliones, Hymenoptera and Thysonoptera were suppressed after pesticides/insecticides spraying. Bio-insecticides in organic fields had a non-significant effect on non targeted species and they started to increase in abundance after 7 days of spraying, whereas insecticide treatment in conventional fields had a significant long-term effect on non targeted arthropods and short term effect on pests/insects, it started to increase after 21 days of the spraying. These results indicate that insecticide treatment kept non targeted arthropods at low abundance. In conclusion, organic farming does not significantly affected the beneficial-non targeted arthropods biodiversity, whereas preventive insecticide application in conventional fields had significant negative effects on beneficial non targeted arthropods. Therefore, conventional farmers should restrict insecticide applications, unless pest densities reach the thresholds and more desirably can switch to organic farming practices.

  10. Acquisition of Cry1Ac protein by non-target arthropods in Bt soybean fields.

    Directory of Open Access Journals (Sweden)

    Huilin Yu

    Full Text Available Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA. Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults and sampling dates (before, during, and after flowering. Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean.

  11. Aerial arthropod communities of native and invaded forests, Robinson Crusoe Island, Chile.

    Science.gov (United States)

    Hagen, Erin N; Bakker, Jonathan D; Gara, Robert I

    2010-08-01

    Invasive species significantly contribute to biological change and threaten biodiversity, with a growing body of evidence that plant invasions affect higher trophic levels. We explored the relative importance of plant invasion and forest structure on aerial arthropod abundance, diversity, and composition on Robinson Crusoe Island, Chile. We used flight intercept traps to sample aerial arthropods within distinct canopy strata of native and invaded forests over 3-mo periods in 2006 and 2007. Arthropod abundance and diversity were higher in native than invaded forest, and arthropod communities were distinct between forest types. In both forest types, arthropod abundance was highest in the lower canopy, and canopy strata exhibited some differences in arthropod community composition. Several morphospecies were distinctly associated with each forest type. The strong differences in aerial arthropod communities associated with the invasion of native forest by non-native plants may affect other trophic levels, such as insectivorous birds. Steps to stop invasive plant spread and to restore native forest composition and structure are needed to safeguard the integrity of native communities, from plants to higher-level consumers.

  12. Arthropods of Medical Importance in Brazil: Retrospective Epidemiological Information about Accidents Involving these Animals

    Directory of Open Access Journals (Sweden)

    Danon Clemes Cardoso

    2009-01-01

    Full Text Available Problem statement: The epidemiological information about arthropods bites/sting in Criciúma region no was reported. The aim of this Research was to draw the epidemiologic profile of accidents with arthropods in Criciúma region. Approach: The information regarding accidents with arthropods from 1994-2006 was prospectively collected from SINAN (System of Injury Notification Information files of the 21a Municipal Health Secretary of Criciúma region. Was calculated the frequency for each variable studied and incidence coefficient for period of study. Results: Results were recorded 1821 notifications of accidents with arthropods in region studied. The numbers of occurrence increased along of the years studied. The arthropod that most result in accidents was the spider with 1,126 (75.9% cases followed by Honeybees and others Arthropods with 149 (10.0% cases, Caterpillars including Lonomia genus and others genera (54/3.7% and scorpions with the least number of accidents with 6 (0.4% cases. The incidence of accidents every thousand inhabitants had a significant increase starting in the year of 2000. The majority of accidents occurred in the warmest months, increasing in the spring and summer seasons. Was recorded more than twice of accidents with arthropods in Urban area than in rural areas. The Chi-square test revealed that the frequency of accidents between locations and type of arthropods is different. Likewise, the number the victims and activity type in moment of the bite/sting had been a differ behavior between arthropods type. However, the number of accidents involving victims of male and female gender is equal. Conclusion: Epidemiological studies of this type in the extreme south of Santa Catarina are scarce. Only few studies have reported the patterns of occurrence and incidence of accidents with poisonous animals. These and other studies are of great importance for implementation of measures mitigation programs and education for

  13. Sweeping beauty: is grassland arthropod community composition effectively estimated by sweep netting?

    Science.gov (United States)

    Spafford, Ryan D; Lortie, Christopher J

    2013-01-01

    Arthropods are critical ecosystem components due to their high diversity and sensitivity to perturbation. Furthermore, due to their ease of capture they are often the focus of environmental health surveys. There is much debate regarding the best sampling method to use in these surveys. Sweep netting and pan trapping are two sampling methods commonly used in agricultural arthropod surveys, but have not been contrasted in natural grassland systems at the community level. The purpose of this study was to determine whether sweep netting was effective at estimating arthropod diversity at the community level in grasslands or if supplemental pan trapping was needed. Arthropods were collected from grassland sites in Montana, USA, in the summer of 2011. The following three standardized evaluation criteria (consistency, reliability, and precision) were developed to assess the efficacy of sweep netting and pan trapping, based on analyses of variations in arthropod abundances, species richness, evenness, capture frequency, and community composition. Neither sampling method was sufficient in any criteria to be used alone for community-level arthropod surveys. On a taxa-specific basis, however, sweep netting was consistent, reliable, and precise for Thysanoptera, infrequently collected (i.e., rare) insects, and Arachnida, whereas pan trapping was consistent, reliable, and precise for Collembola and bees, which is especially significant given current threats to the latter's populations worldwide. Species-level identifications increase the detected dissimilarity between sweep netting and pan trapping. We recommend that community-level arthropod surveys use both sampling methods concurrently, at least in grasslands, but likely in most nonagricultural systems. Target surveys, such as monitoring bee communities in fragmented grassland habitat or where detailed information on behavior of the target arthropod groups is available can in some instances employ singular methods. As a

  14. Grassland Arthropods Are Controlled by Direct and Indirect Interactions with Cattle but Are Largely Unaffected by Plant Provenance.

    Directory of Open Access Journals (Sweden)

    Kelly Anne Farrell

    Full Text Available Cattle grazing and invasion by non-native plant species are globally-ubiquitous changes occurring to plant communities that are likely to reverberate through whole food webs. We used a manipulative field experiment to quantify how arthropod community structure differed in native and non-native California grassland communities in the presence and absence of grazing. The arthropod community was strongly affected by cattle grazing: the biovolume of herbivorous arthropods was 79% higher in grazed than ungrazed plots, whereas the biovolume of predatory arthropods was 13% higher in ungrazed plots. In plots where non-native grasses were grazed, arthropod biovolume increased, possibly in response to increased plant productivity or increased nutritional quality of rapidly-growing annual plants. Grazing may thus affect plant biomass both through the direct removal of biomass, and through arthropod-mediated impacts. We also expected the arthropod community to differ between native and non-native plant communities; surprisingly, arthropod richness and diversity did not vary consistently between these grass community types, although arthropod abundance was slightly higher in plots with native and ungrazed grasses. These results suggest that whereas cattle grazing affects the arthropod community via direct and indirect pathways, arthropod community changes commonly associated with non-native plant invasions may not be due to the identity or dominance of the invasive species in those systems, but to accompanying changes in plant traits or functional group composition, not seen in this experiment because of the similarity of the plant communities.

  15. Longleaf Pine Characterists Associated with Arthropods Available for Red-Cockaded Woodpeckers

    Energy Technology Data Exchange (ETDEWEB)

    Hanula, J.L.; Franzreb, K.E.; Pepper, W.D.

    1999-01-25

    The authors sampled arthropods on 300 longleaf pine under varying stand conditions and ranging in age from 20 to 100 years. The most diverse orders were beetles, spiders, ants, wasps and bees. The most abundant were aphids and Hymenoptera with a large number of ants. Arthropod biomass per tree increased in age up to 65-70 years, but biomass was highest in the youngest stands. Arthropods were positively correlated to bark thickness and tree diameter, but negatively related to the stand basal area. No relationships were found between abundance and ground vegetation conditions.

  16. Acquisition of Cry1Ac Protein by Non-Target Arthropods in Bt Soybean Fields

    OpenAIRE

    Huilin Yu; Jörg Romeis; Yunhe Li; Xiangju Li; Kongming Wu

    2014-01-01

    Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentra...

  17. Role of microRNAs in arbovirus/vector interactions.

    Science.gov (United States)

    Asgari, Sassan

    2014-09-23

    The role of microRNAs (miRNAs) as small non-coding RNAs in regulation of gene expression has been recognized. They appear to be involved in regulation of a wide range of cellular pathways that affect several biological processes such as development, the immune system, survival, metabolism and host-pathogen interactions. Arthropod-borne viruses impose great economic and health risks around the world. Recent advances in miRNA biology have shed some light on the role of these small RNAs in vector-virus interactions. In this review, I will reflect on our current knowledge on the role of miRNAs in arbovirus-vector interactions and the potential avenues for their utilization in limiting virus replication and/or transmission.

  18. Concise vector analysis

    CERN Document Server

    Eliezer, C J; Maxwell, E A; Sneddon, I N

    1963-01-01

    Concise Vector Analysis is a five-chapter introductory account of the methods and techniques of vector analysis. These methods are indispensable tools in mathematics, physics, and engineering. The book is based on lectures given by the author in the University of Ceylon.The first two chapters deal with vector algebra. These chapters particularly present the addition, representation, and resolution of vectors. The next two chapters examine the various aspects and specificities of vector calculus. The last chapter looks into some standard applications of vector algebra and calculus.This book wil

  19. Introduction to symposium: Arthropods and wildlife conservation: synergy in complex biological systems

    Science.gov (United States)

    The symposium will discuss the effects of arthropods and other stressors on wildlife conservation programs. Speakers with affiliations in wildlife biology, parasitology and entomology will be included in the program. Research of national and international interest will be presented....

  20. Manipulation of arthropod sex determination by endosymbionts : Diversity and molecular mechanisms

    NARCIS (Netherlands)

    Ma, W. -J.; Vavre, F.; Beukeboom, L. W.

    2014-01-01

    Arthropods exhibit a large variety of sex determination systems both at the chromosomal and molecular level. Male heterogamety, female heterogamety, and haplodiploidy occur frequently, but partially different genes are involved. Endosymbionts, such as Wolbachia, Cardinium, Rickettsia, and Spiroplasm

  1. Arthropod trace fossils from the Zhujiaqing Formation (Meishucunian, Yunnan) and their palaeobiological implications

    Institute of Scientific and Technical Information of China (English)

    Bernd WEBER1; ZHU Maoyan

    2003-01-01

    Along with several non-arthropod ichnotaxa and rather non-specific scratchmarks, the Upper Phosphate of the Zhujiaqing Formation (Early Meishucunian Stage) in Eastern Yunnan yielded well-preserved resting and digging traces of the Rusophycus-type interpreted as resting traces of unknown large arthropods (ca. 3~6 cm in length). The discernible morphological details of these trace fossils enable a rough estimation of the body plan characteristics of the trace originators placing the latter doubtless into the early arthropods, if not euarthropods. The spectrum of the Meishucunian ichnoassemblage, especially the different types of arthropod repichnia point to the existence of a complex benthic ecosystem consisting of animals with different behavioural patterns and life styles already during the earliest Cambrian (Nemakit-Daldyn), and demands the assumption of a longer evolutionary past history of the benthic life on earth before the so-called "Cambrian Explosion" of the metazoans.

  2. Exceptional preservation of eye structure in arthropod visual predators from the Middle Jurassic.

    Science.gov (United States)

    Vannier, Jean; Schoenemann, Brigitte; Gillot, Thomas; Charbonnier, Sylvain; Clarkson, Euan

    2016-01-01

    Vision has revolutionized the way animals explore their environment and interact with each other and rapidly became a major driving force in animal evolution. However, direct evidence of how ancient animals could perceive their environment is extremely difficult to obtain because internal eye structures are almost never fossilized. Here, we reconstruct with unprecedented resolution the three-dimensional structure of the huge compound eye of a 160-million-year-old thylacocephalan arthropod from the La Voulte exceptional fossil biota in SE France. This arthropod had about 18,000 lenses on each eye, which is a record among extinct and extant arthropods and is surpassed only by modern dragonflies. Combined information about its eyes, internal organs and gut contents obtained by X-ray microtomography lead to the conclusion that this thylacocephalan arthropod was a visual hunter probably adapted to illuminated environments, thus contradicting the hypothesis that La Voulte was a deep-water environment. PMID:26785293

  3. A systematic review of arthropod community diversity in association with invasive plants

    OpenAIRE

    Spafford, Ryan D; Lortie, Christopher J.; Butterfield, Bradley J.

    2013-01-01

    Invasive plants represent a significant financial burden for land managers and also have the potential to severely degrade ecosystems. Arthropods interact strongly with plants, relying on them for food, shelter, and as nurseries for their young. For these reasons, the impacts of plant invasions are likely strongly reflected by arthropod community dynamics including diversity and abundances. A systematic review was conducted to ascertain the state of the literature with respect to plant invade...

  4. Possible developmental mechanisms underlying the origin of the crown lineages of arthropods

    Institute of Scientific and Technical Information of China (English)

    WANG Xiuqiang; CHEN Junyuan

    2004-01-01

    The extraordinarily preserved, diverse arthropod fauna from the Lower Cambrian Maotianshan shale, central Yunnan (southwest China), represents different evolutionary stages stepping from stem lineages towards crown arthropods (also called euarthropods), which makes this fauna extremely significant for discussion of the origin and early diversification of the arthropods. Anatomical analyses of the Maotianshan shale arthropods strongly indicate that the origin of crown arthropods involved three major evolutionary events, arthrodisation, arthropodisation and cephali- zation. We try to explore possible evolutionary changes of the developmental mechanism that may have underlain origins of euarthropod appendage and head. Fossil evidence suggests that the formation of a jointed limb known as arthropodisation and formation of multi-segmented head (called cephalization), which characterize euarthropods, is an event after arthrodisation characterized with the formation of segmented-exoskeleton and the joint membrane between tergites. We propose that the Hox complex was already operating at least as early as in the Early Cambrian and is responsible for the formation of the joint membrane between two semgents through Hox gene regulation along the D-V and P-D axis. Fossil evidence indicates that the head in ground state of arthropods consists only of two segments, an ocular and an antennal one. The formation of multiple segmented, euarthropod head (called syncephalon) from the two-segmented head was a separate event, which is called cephali- zation. Presence of the Hox gene head expression domain and change of developmental mechanism in head segments might be responsible for the formation of the syncephalon and this event has been broadly finished in the Early Cambrian arthropods. The post-oral limbs in the early syncephalons as evidenced from the Lower Cambrian Maotianshan shale arthropods however were almost identical to those in trunk. Therefore we proposed that the Hox

  5. Arthropod diversity in pure oak forests of coppice origin in northern Thrace (Turkey

    Directory of Open Access Journals (Sweden)

    Keten A

    2015-10-01

    Full Text Available Oak (Quercus spp. forests are among the most important forest types in Turkey. In the past, oak forests were managed through coppice clear-cutting, but in recent decades they have mostly been converted to high forest. This study was aimed at explaining how arthropod diversity is affected during conversion from coppice to high oak forest and during the early stages of coppice succession. We tested the hypothesis that arthropod richness, abundance and diversity in coppice oak sites varied according to stand age and a number of other forest characteristics. Arthropod communities were sampled in 50 plots using four different methods: pitfall traps, sweep nets, sticky cards and cloth shaking. A total of 13 084 individuals were collected and classified into 193 Recognizable Taxonomic Units (RTUs, with the most RTUs and the greatest number of specimens captured by sweep netting. We identified 17 taxa within RTU’s with more than 1% of the captured arthropods, which constituted 75% of the total specimens. The number of RTUs varied significantly according to trap type. Arthropod richness and Shannon-Wiener biodiversity index (H′ increased with elevation and precipitation. In young (1-40 yrs-old and middle-aged (41-80 yrs stands, arthropod biodiversity was not significantly affected by stand type, but slightly increased with diameter at breast height and tree height. Forest characteristics, such as the litter layer, understory and crown diameter, weakly influenced arthropod richness and abundance. Cluster analysis revealed that stand types and trap types differed taxonomically. Principal component analysis showed that stand types were clearly separated by the stand parameters measured. Insect families (Formicidae, Thripidae, Lygaeidae, Dolichopodidae, Luaxanidae, Cicadellidae and Ichneumonidae could potentially be used as indicators of coppice oak conditions. As the coppice oak changes to mature forest, further studies are needed to better assess the

  6. Dynamics of the leaf-litter arthropod fauna following fire in a neotropical woodland savanna.

    Directory of Open Access Journals (Sweden)

    Heraldo L Vasconcelos

    Full Text Available Fire is an important agent of disturbance in tropical savannas, but relatively few studies have analyzed how soil-and-litter dwelling arthropods respond to fire disturbance despite the critical role these organisms play in nutrient cycling and other biogeochemical processes. Following the incursion of a fire into a woodland savanna ecological reserve in Central Brazil, we monitored the dynamics of litter-arthropod populations for nearly two years in one burned and one unburned area of the reserve. We also performed a reciprocal transplant experiment to determine the effects of fire and litter type on the dynamics of litter colonization by arthropods. Overall arthropod abundance, the abundance of individual taxa, the richness of taxonomic groups, and the species richness of individual taxa (Formiciade were lower in the burned site. However, both the ordinal-level composition of the litter arthropod fauna and the species-level composition of the litter ant fauna were not dramatically different in the burned and unburned sites. There is evidence that seasonality of rainfall interacts with fire, as differences in arthropod abundance and diversity were more pronounced in the dry than in the wet season. For many taxa the differences in abundance between burned and unburned sites were maintained even when controlling for litter availability and quality. In contrast, differences in abundance for Collembola, Formicidae, and Thysanoptera were only detected in the unmanipulated samples, which had a lower amount of litter in the burned than in the unburned site throughout most of our study period. Together these results suggest that arthropod density declines in fire-disturbed areas as a result of direct mortality, diminished resources (i.e., reduced litter cover and less favorable microclimate (i.e., increased litter desiccation due to reduction in tree cover. Although these effects were transitory, there is evidence that the increasingly prevalent fire

  7. Influence of Selective Insecticides and Cropping System on Arthropod Natural Enemies in Soybean

    OpenAIRE

    Whalen, Rebecca Anne

    2016-01-01

    Arthropod natural enemies play a key role in controlling potentially damaging pest populations in agroecosystems. An abundant and diverse natural enemy community is associated with higher yields in a variety of crops. Certain aspects of soybean production can make a field more or less amenable to a robust natural enemy community. For instance, commonly used broad-spectrum insecticides which are highly toxic to most arthropods can decrease natural enemy densities and allow for secondary pest o...

  8. Bison grazing increases arthropod abundance and diversity in a tallgrass prairie.

    Science.gov (United States)

    Moran, Matthew D

    2014-10-01

    How grazing-induced ecosystem changes by ungulates indirectly affect other consumers is a question of great interest. I investigated the effect of grazing by American Bison (Bos bison L.) on an arthropod community in tallgrass prairie. Grazing increased the abundance of arthropods, an increase that was present in both herbivorous and carnivorous assemblages, but not in detritivores. The increase in herbivores and reduction in plant biomass from grazing resulted in an arthropod herbivore load almost three times higher in grazed plots compared with controls. Among herbivores, the sap-feeding insect guild was dramatically more abundant, while chewing herbivores were not affected. Herbivorous and carnivorous arthropod richness was higher in grazed plots, although the response was strongest among herbivores. Arthropod abundance on individual grasses and forbs was significantly higher in grazed areas, while plant type had no effect on abundance, indicating that the change was ecosystem-wide and not simply in response to a reduction in grass biomass from grazing. The response of arthropods to grazing was strongest in the early part of the growing season. Published research shows that ungulate grazing, although decreasing available biomass to other consumers, enhances plant quality by increasing nitrogen level in plants. The arthropod results of this study suggest higher plant quality outweighs the potential negative competitive effects of plant biomass removal, although other activities of bison could not be ruled out as the causative mechanism. Because arthropods are extremely abundant organisms in grasslands and a food source for other consumers, bison may represent valuable management tools for maintaining biodiversity. PMID:25198902

  9. Genetic Variation in Functional Traits Influences Arthropod Community Composition in Aspen (Populus tremula L.)

    OpenAIRE

    Robinson, Kathryn M; Pär K Ingvarsson; Jansson, Stefan; Albrectsen, Benedicte R.

    2012-01-01

    We conducted a study of natural variation in functional leaf traits and herbivory in 116 clones of European aspen, Populus tremula L., the Swedish Aspen (SwAsp) collection, originating from ten degrees of latitude across Sweden and grown in a common garden. In surveys of phytophagous arthropods over two years, we found the aspen canopy supports nearly 100 morphospecies. We identified significant broad-sense heritability of plant functional traits, basic plant defence chemistry, and arthropod ...

  10. VectorBase

    Data.gov (United States)

    U.S. Department of Health & Human Services — VectorBase is a Bioinformatics Resource Center for invertebrate vectors. It is one of four Bioinformatics Resource Centers funded by NIAID to provide web-based...

  11. Insulated Foamy Viral Vectors.

    Science.gov (United States)

    Browning, Diana L; Collins, Casey P; Hocum, Jonah D; Leap, David J; Rae, Dustin T; Trobridge, Grant D

    2016-03-01

    Retroviral vector-mediated gene therapy is promising, but genotoxicity has limited its use in the clinic. Genotoxicity is highly dependent on the retroviral vector used, and foamy viral (FV) vectors appear relatively safe. However, internal promoters may still potentially activate nearby genes. We developed insulated FV vectors, using four previously described insulators: a version of the well-studied chicken hypersensitivity site 4 insulator (650cHS4), two synthetic CCCTC-binding factor (CTCF)-based insulators, and an insulator based on the CCAAT box-binding transcription factor/nuclear factor I (7xCTF/NF1). We directly compared these insulators for enhancer-blocking activity, effect on FV vector titer, and fidelity of transfer to both proviral long terminal repeats. The synthetic CTCF-based insulators had the strongest insulating activity, but reduced titers significantly. The 7xCTF/NF1 insulator did not reduce titers but had weak insulating activity. The 650cHS4-insulated FV vector was identified as the overall most promising vector. Uninsulated and 650cHS4-insulated FV vectors were both significantly less genotoxic than gammaretroviral vectors. Integration sites were evaluated in cord blood CD34(+) cells and the 650cHS4-insulated FV vector had fewer hotspots compared with an uninsulated FV vector. These data suggest that insulated FV vectors are promising for hematopoietic stem cell gene therapy. PMID:26715244

  12. Rhotrix Vector Spaces

    Science.gov (United States)

    Aminu, Abdulhadi

    2010-01-01

    By rhotrix we understand an object that lies in some way between (n x n)-dimensional matrices and (2n - 1) x (2n - 1)-dimensional matrices. Representation of vectors in rhotrices is different from the representation of vectors in matrices. A number of vector spaces in matrices and their properties are known. On the other hand, little seems to be…

  13. Linking membrane physical properties and low temperature tolerance in arthropods.

    Science.gov (United States)

    Waagner, Dorthe; Bouvrais, Hélène; Ipsen, John H; Holmstrup, Martin

    2013-12-01

    Maintenance of membrane fluidity is of crucial importance in ectotherms experiencing thermal changes. This maintenance has in ectotherms most often been indicated using indirect measures of biochemical changes of phospholipid membranes, which is then assumed to modulate the physico-chemical properties of the membrane. Here, we measure bending rigidity characterizing the membrane flexibility of re-constituted membrane vesicles to provide a more direct link between membrane physical characteristics and low temperature tolerance. Bending rigidity of lipid bilayers was measured in vitro using Giant Unilamellar Vesicles formed from phospholipid extracts of the springtail, Folsomia candida. The bending rigidity of these membranes decreased when exposed to 0.4 vol% ethanol (0.23 mM/L). Springtails exposed to ethanol for 24h significantly increased their cold shock tolerance. Thus, by chemically inducing decreased membrane rigidity, we have shown a direct link between the physico-chemical properties of the membranes and the capacity to tolerate low temperature in a chill-susceptible arthropod. PMID:24080490

  14. Arthropod phylogeny based on eight molecular loci and morphology

    Science.gov (United States)

    Giribet, G.; Edgecombe, G. D.; Wheeler, W. C.

    2001-01-01

    The interrelationships of major clades within the Arthropoda remain one of the most contentious issues in systematics, which has traditionally been the domain of morphologists. A growing body of DNA sequences and other types of molecular data has revitalized study of arthropod phylogeny and has inspired new considerations of character evolution. Novel hypotheses such as a crustacean-hexapod affinity were based on analyses of single or few genes and limited taxon sampling, but have received recent support from mitochondrial gene order, and eye and brain ultrastructure and neurogenesis. Here we assess relationships within Arthropoda based on a synthesis of all well sampled molecular loci together with a comprehensive data set of morphological, developmental, ultrastructural and gene-order characters. The molecular data include sequences of three nuclear ribosomal genes, three nuclear protein-coding genes, and two mitochondrial genes (one protein coding, one ribosomal). We devised new optimization procedures and constructed a parallel computer cluster with 256 central processing units to analyse molecular data on a scale not previously possible. The optimal 'total evidence' cladogram supports the crustacean-hexapod clade, recognizes pycnogonids as sister to other euarthropods, and indicates monophyly of Myriapoda and Mandibulata.

  15. [Structure of parasitic arthropod communities in forest small mammals].

    Science.gov (United States)

    Balashov, Iu S

    2004-01-01

    Species composition and structure of ectoparasite arthropod communities were examined all year round six years in the bank vole Clethrionomys glareolus, Ural wood mouse Apodemus uralensis and the common shrew Sorex araneus in forests of the Ilmen'-Volkhov depression. In total, 4500 host samples have been examined and all ectoparasites have been collected. The species composition of ectoparasite community in small mammal species are as follows: the bank vole--29 insect, tick and mite species, the common shrew--23 species, the Ural wood mouse--16 species. In forest biotopes, many temporary ectoparasitic species occur on several host species living in the same habitats under a forest canopy and contacting each other. A parasitic supracommunity in the ecosystem examined has a pool of temporary ectoparasites, which is available for all the community of small mammals. A role of different rodent and shrew species are hosts of insects and ticks changes depending on a density of potential host populations and numerous other environment factors. PMID:15656091

  16. Covariantised Vector Galileons

    CERN Document Server

    Hull, Matthew; Tasinato, Gianmassimo

    2015-01-01

    Vector galileons are ghost-free systems containing higher derivative interactions of vector fields. They break the vector gauge symmetry, and the dynamics of the longitudinal vector polarizations acquire a Galileon symmetry in an appropriate decoupling limit in Minkowski space. Using an ADM approach, we carefully reconsider the coupling with gravity of vector galileons, with the aim of studying the necessary conditions to avoid the propagation of ghosts. We develop arguments that put on a more solid footing the results previously obtained in the literature. Moreover, working in analogy with the scalar counterpart, we find indications for the existence of a `beyond Horndeski' theory involving vector degrees of freedom, that avoids the propagation of ghosts thanks to secondary constraints. In addition, we analyse a Higgs mechanism for generating vector galileons through spontaneous symmetry breaking, and we present its consistent covariantisation.

  17. Mineral cycling in soil and litter arthropod food chains. Progress report, November 1, 1980-October 31, 1981

    International Nuclear Information System (INIS)

    Progress and current status are reported for research projects concerned with mineral element and nutrient dynamics in soil arthropod food chains. Research is performed within the larger context of terrestrial decomposition, in which soil arthropods may act as regulators of nutrient dynamics during decomposition. Research is measuring rates of nutrient accumulation and excretion by using radioactive tracer analogs of nutrients. This year, emphasis has been placed on field work in which soil arthropod population size and nutrients inputs were varied experimentally. The presence of microarthropods in field microcosms increased the mineralization of N and P in each case, but rates were not correlated with arthropod densities. Experiments recently started are using both arthropod and microfloral inhibitors, in open systems on the forest floor, with the objective of quantifying arthropod enhancement of microbial immobilization of nutrients

  18. A New Arthropod, Guangweicaris Luo, Fu et Hu gen. nov.from the Early Cambrian Guanshan Fauna, Kunming, China

    Institute of Scientific and Technical Information of China (English)

    LUO Huilin; FU Xiaoping; HU Shixue; LI Yong; HOU Shuguang; YOU Ting; PANG Jiyuan; LIU Qi

    2007-01-01

    The Guanshan Fauna is a soft-bodied fauna dominated by arthropods (including trilobites,trilobitoides, Tuzoia, Isoxys, and bradorids) in association with priapulids, brachiopods,anomalocaridids, vetulicoliids, sponges, chancellorids, and echinoderms. This paper reports and describes a new arthropod from the yellowish green mudstone at the lower part of the Wulongqing Formation, Canglangpuan Stage, Lower Cambrian in Kunming, Yunnan, China. The stratigraphic and geographic distribution, classification, fossil preservation, life style of this new arthropod and comparisons with other fossil arthropods are also discussed in details. The discovery and research of the non-mineralized arthropod, Guangweicaris Luo, Fu et Hu gen. nov. from the Guanshan Fauna adds new members to the taxonomic list and provides new information to the evolution of early arthropods.Furthermore, this study would shed new light into the "Cambrian Explosion" and the evolution of early life.

  19. The Diversity and Abundance of Small Arthropods in Onion, Allium cepa, Seed Crops, and their Potential Role in Pollination

    OpenAIRE

    Walker, M.K.; Howlett, B. G.; Wallace, A.R.; Mccallum, J. A.; Teulon, D.A.J.

    2011-01-01

    Onion, Allium cepa L. (Asparagales: Amaryllidaceae), crop fields grown for seed production require arthropod pollination for adequate seed yield. Although many arthropod species visit A. cepa flowers, for most there is little information on their role as pollinators. Small flower visiting arthropods (body width < 3 mm) in particular are rarely assessed. A survey of eight flowering commercial A. cepa seed fields in the North and South Islands of New Zealand using window traps revealed that sma...

  20. The evolution of virulence of West Nile virus in a mosquito vector: implications for arbovirus adaptation and evolution

    OpenAIRE

    Alexander T. Ciota; Ehrbar, Dylan J.; MATACCHIERO, AMY C.; Van Slyke, Greta A; Kramer, Laura D.

    2013-01-01

    Background Virulence is often coupled with replicative fitness of viruses in vertebrate systems, yet the relationship between virulence and fitness of arthropod-borne viruses (arboviruses) in invertebrates has not been evaluated. Although the interactions between vector-borne pathogens and their invertebrate hosts have been characterized as being largely benign, some costs of arbovirus exposure have been identified for mosquitoes. The extent to which these costs may be strain-specific and the...

  1. Large-scale experimental landscapes reveal distinctive effects of patch shape and connectivity on arthropod communities.

    Energy Technology Data Exchange (ETDEWEB)

    Orrock, John, L.; Curler, Gregory, R.; Danielson, Brent, J.; Coyle, David. R.

    2011-09-14

    The size, shape, and isolation of habitat patches can affect organism behavior and population dynamics, but little is known about the relative role of shape and connectivity in affecting ecological communities at large spatial scales. Using six sampling sessions from July 2001 until August 2002, we collected 33,685 arthropods throughout seven 12-ha experimental landscapes consisting of clear-cut patches surrounded by a matrix of mature pine forest. Patches were explicitly designed to manipulate connectivity (via habitat corridors) independently of area and edge effects. We found that patch shape, rather than connectivity, affected ground-dwelling arthropod richness and beta diversity (i.e. turnover of genera among patches). Arthropod communities contained fewer genera and exhibited less turnover in high-edge connected and high-edge unconnected patches relative to low-edge unconnected patches of similar area. Connectivity, rather than patch shape, affected the evenness of ground-dwelling arthropod communities; regardless of patch shape, high-edge connected patches had lower evenness than low- or high-edge unconnected patches. Among the most abundant arthropod orders, increased richness in low-edge unconnected patches was largely due to increased richness of Coleoptera, whereas Hymenoptera played an important role in the lower evenness in connected patches and patterns of turnover. These findings suggest that anthropogenic habitat alteration can have distinct effects on ground-dwelling arthropod communities that arise due to changes in shape and connectivity. Moreover, this work suggests that corridors, which are common conservation tools that change both patch shape and connectivity, can have multiple effects on arthropod communities via different mechanisms, and each effect may alter components of community structure.

  2. Phylogeny and life habits of Early Arthropods-Predation in the Early Cambrian Sea

    Institute of Scientific and Technical Information of China (English)

    Andreas MAAS; Dieter WALOSZEK; CHEN Junyuan; Andreas BRAUN; WANG Xiuqiang; HUANG Diying

    2004-01-01

    We investigated two new arthropods from the Maotianshan-Shale fauna of southern China in the course of our research on life strategies, particularly predation, in Early Cambrian marine macrofaunal biota. One form clearly belongs to the so-called "great-appendage" arthropods, animals that were, most likely, active predators catching prey with their first pair of large, specialized frontoventral appendages. Based on this, we hypothesize that the new species and many others, if not all, of the "great-appendage" arthropods were derivatives of the chelicerate stem lineage and not forms having branched off at different nodes along the evolutionary lineage of the Arthropoda. Rather, we consider the "great-appendage" arthropods as belonging to a monophyletic clade, which modified autapomorphically their first pair of appendages (antennae in general arthropod terminology) into raptorial organs for food capture. The second new form resembles another Maotianshan-Shale arthropod, Fuxianhuia protensa, in sharing a head made of only two separate segments, a small segment bearing oval eyes laterally, and another bearing a large tergite, which forms a wide shield freely overhanging the subsequent narrow trunk segments. This segment bears a single pair of rather short anteriorly directed uniramous appendages, considered as the "still" limb-shaped antennae. Particularly the evolutionary status of head and limbs of these two forms suggests that both are representatives of the early part of the stem lineage toward the crown-group of Arthropoda, the Euarthropoda. These forms appear rather unspecialized, but may have been but simple predators. This adds to our hypothesis that predation was a common, if not dominant feeding strategy in the Cambrian, at least for arthropods.

  3. Habitat and species identity, not diversity, predict the extent of refuse consumption by urban arthropods.

    Science.gov (United States)

    Youngsteadt, Elsa; Henderson, Ryanna C; Savage, Amy M; Ernst, Andrew F; Dunn, Robert R; Frank, Steven D

    2015-03-01

    Urban green spaces provide ecosystem services to city residents, but their management is hindered by a poor understanding of their ecology. We examined a novel ecosystem service relevant to urban public health and esthetics: the consumption of littered food waste by arthropods. Theory and data from natural systems suggest that the magnitude and resilience of this service should increase with biological diversity. We measured food removal by presenting known quantities of cookies, potato chips, and hot dogs in street medians (24 sites) and parks (21 sites) in New York City, USA. At the same sites, we assessed ground-arthropod diversity and abiotic conditions, including history of flooding during Hurricane Sandy 7 months prior to the study. Arthropod diversity was greater in parks (on average 11 hexapod families and 4.7 ant species per site), than in medians (nine hexapod families and 2.7 ant species per site). However, counter to our diversity-based prediction, arthropods in medians removed 2-3 times more food per day than did those in parks. We detected no effect of flooding (at 19 sites) on this service. Instead, greater food removal was associated with the presence of the introduced pavement ant (Tetramorium sp. E) and with hotter, drier conditions that may have increased arthropod metabolism. When vertebrates also had access to food, more was removed, indicating that arthropods and vertebrates compete for littered food. We estimate that arthropods alone could remove 4-6.5 kg of food per year in a single street median, reducing its availability to less desirable fauna such as rats. Our results suggest that species identity and habitat may be more relevant than diversity for predicting urban ecosystem services. Even small green spaces such as street medians provide ecosystem services that may complement those of larger habitat patches across the urban landscape.

  4. Reconstructing the phylogeny of 21 completely sequenced arthropod species based on their motor proteins

    Directory of Open Access Journals (Sweden)

    Kollmar Martin

    2009-04-01

    Full Text Available Abstract Background Motor proteins have extensively been studied in the past and consist of large superfamilies. They are involved in diverse processes like cell division, cellular transport, neuronal transport processes, or muscle contraction, to name a few. Vertebrates contain up to 60 myosins and about the same number of kinesins that are spread over more than a dozen distinct classes. Results Here, we present the comparative genomic analysis of the motor protein repertoire of 21 completely sequenced arthropod species using the owl limpet Lottia gigantea as outgroup. Arthropods contain up to 17 myosins grouped into 13 classes. The myosins are in almost all cases clear paralogs, and thus the evolution of the arthropod myosin inventory is mainly determined by gene losses. Arthropod species contain up to 29 kinesins spread over 13 classes. In contrast to the myosins, the evolution of the arthropod kinesin inventory is not only determined by gene losses but also by many subtaxon-specific and species-specific gene duplications. All arthropods contain each of the subunits of the cytoplasmic dynein/dynactin complex. Except for the dynein light chains and the p150 dynactin subunit they contain single gene copies of the other subunits. Especially the roadblock light chain repertoire is very species-specific. Conclusion All 21 completely sequenced arthropods, including the twelve sequenced Drosophila species, contain a species-specific set of motor proteins. The phylogenetic analysis of all genes as well as the protein repertoire placed Daphnia pulex closest to the root of the Arthropoda. The louse Pediculus humanus corporis is the closest relative to Daphnia followed by the group of the honeybee Apis mellifera and the jewel wasp Nasonia vitripennis. After this group the rust-red flour beetle Tribolium castaneum and the silkworm Bombyx mori diverged very closely from the lineage leading to the Drosophila species.

  5. Index Sets and Vectorization

    Energy Technology Data Exchange (ETDEWEB)

    Keasler, J A

    2012-03-27

    Vectorization is data parallelism (SIMD, SIMT, etc.) - extension of ISA enabling the same instruction to be performed on multiple data items simultaeously. Many/most CPUs support vectorization in some form. Vectorization is difficult to enable, but can yield large efficiency gains. Extra programmer effort is required because: (1) not all algorithms can be vectorized (regular algorithm structure and fine-grain parallelism must be used); (2) most CPUs have data alignment restrictions for load/store operations (obey or risk incorrect code); (3) special directives are often needed to enable vectorization; and (4) vector instructions are architecture-specific. Vectorization is the best way to optimize for power and performance due to reduced clock cycles. When data is organized properly, a vector load instruction (i.e. movaps) can replace 'normal' load instructions (i.e. movsd). Vector operations can potentially have a smaller footprint in the instruction cache when fewer instructions need to be executed. Hybrid index sets insulate users from architecture specific details. We have applied hybrid index sets to achieve optimal vectorization. We can extend this concept to handle other programming models.

  6. Modeling the habitat suitability for the arbovirus vector Aedes albopictus (Diptera: Culicidae) in Germany.

    Science.gov (United States)

    Koch, Lisa K; Cunze, Sarah; Werblow, Antje; Kochmann, Judith; Dörge, Dorian D; Mehlhorn, Heinz; Klimpel, Sven

    2016-03-01

    Climatic changes raise the risk of re-emergence of arthropod-borne virus outbreaks globally. These viruses are transmitted by arthropod vectors, often mosquitoes. Due to increasing worldwide trade and tourism, these vector species are often accidentally introduced into many countries beyond their former distribution range. Aedes albopictus, a well-known disease vector, was detected for the first time in Germany in 2007, but seems to have failed establishment until today. However, the species is known to occur in other temperate regions and a risk for establishment in Germany remains, especially in the face of predicted climate change. Thus, the goal of the study was to estimate the potential distribution of Ae. albopictus in Germany. We used ecological niche modeling in order to estimate the potential habitat suitability for this species under current and projected future climatic conditions. According to our model, there are already two areas in western and southern Germany that appear suitable for Ae. albopictus under current climatic conditions. One of these areas lies in Baden-Wuerttemberg, the other in North-Rhine Westphalia in the Ruhr region. Furthermore, projections under future climatic conditions show an increase of the modeled habitat suitability throughout Germany. Ae. albopictus is supposed to be better acclimated to colder temperatures than other tropical vectors and thus, might become, triggered by climate change, a serious threat to public health in Germany. Our modeling results can help optimizing the design of monitoring programs currently in place in Germany. PMID:26634351

  7. Plant pathogen-induced volatiles attract parasitoids to increase parasitism of an insect vector

    Directory of Open Access Journals (Sweden)

    Xavier eMartini

    2014-05-01

    Full Text Available Interactions between plant pathogens and arthropods have been predominantly studied through the prism of herbivorous arthropods. Currently, little is known about the effect of plant pathogens on the third trophic level. This question is particularly interesting in cases where pathogens manipulate host phenotype to increase vector attraction and presumably increase their own proliferation. Indeed, a predator or a parasitoid of a vector may take advantage of this manipulated phenotype to increase its foraging performance. We explored the case of a bacterial pathogen, Candidatus Liberibacter asiaticus (Las, which modifies the odors released by its host plant (citrus trees to attract its vector, the psyllid Diaphorina citri. We found that the specialist parasitoid of D. citri, Tamarixia radiata, was attracted more toward Las-infected than uninfected plants. We demonstrated that this attractiveness was due to the release of methyl salicylate. Parasitization of D. citri nymphs on Las-infected plants was higher than on uninfected controls. Also, parasitization was higher on uninfected plants baited with methyl salicylate than on non-baited controls. This is the first report of a parasitoid ‘eavesdropping’ on a plant volatile induced by bacterial pathogen infection, which also increases effectiveness of host seeking behavior of its herbivorous vector.

  8. Vectorization of a Treecode

    Science.gov (United States)

    Makino, Junichiro

    1990-03-01

    Vectorized algorithms for the force calculation and tree construction in the Barnes-Hut tree algorithm are described. The basic idea for the vectorization of the force calculation is to vectorize the tree traversal across particles, so that all particles in the system traverse the tree simultaneously. The tree construction algorithm also makes use of the fact that particles can be treated in parallel. Thus these algorithms take advantage of the internal parallelism in the N-body system and the tree algorithm most effectively. As a natural result, these algorithms can be used on a wide range of vector/parallel architectures, including current supercomputers and highly parallel architectures such as the Connection Machine. The vectorized code runs about five times faster than the non-vector code on a Cyber 205 for an N-body system with N = 8192.

  9. A negative effect of a pathogen on its vector? A plant pathogen increases the vulnerability of its vector to attack by natural enemies.

    Science.gov (United States)

    de Oliveira, Camila F; Long, Elizabeth Y; Finke, Deborah L

    2014-04-01

    Plant pathogens that are dependent on arthropod vectors for transmission from host to host may enhance their own success by promoting vector survival and/or performance. The effect of pathogens on vectors may be direct or indirect, with indirect effects mediated by increases in host quality or reductions in the vulnerability of vectors to natural enemies. We investigated whether the bird cherry-oat aphid Rhopalosiphum padi, a vector of cereal yellow dwarf virus (CYDV) in wheat, experiences a reduction in rates of attack by the parasitoid wasp Aphidius colemani when actively harboring the plant pathogen. We manipulated the vector status of aphids (virus carrying or virus free) and evaluated the impact on the rate of attack by wasps. We found that vector status did not influence the survival or fecundity of aphids in the absence of parasitoids. However, virus-carrying aphids experienced higher rates of parasitism and greater overall population suppression by parasitoid wasps than virus-free aphids. Moreover, virus-carrying aphids were accepted as hosts by wasps more often than virus-free aphids, with a greater number of wasps stinging virus-carrying aphids following assessment by antennal palpations than virus-free aphids. Therefore, counter to the prevailing idea that persistent vector-borne pathogens enhance the performance of their vectors, we found that infectious aphids actively carrying a plant pathogen experience greater vulnerability to natural enemies. Our results suggest that parasitoids may contribute to the successful biological control of CYDV by disproportionately impacting virus-carrying vectors, and thus reducing the proportion of vectors in the population that are infectious. PMID:24322446

  10. A negative effect of a pathogen on its vector? A plant pathogen increases the vulnerability of its vector to attack by natural enemies.

    Science.gov (United States)

    de Oliveira, Camila F; Long, Elizabeth Y; Finke, Deborah L

    2014-04-01

    Plant pathogens that are dependent on arthropod vectors for transmission from host to host may enhance their own success by promoting vector survival and/or performance. The effect of pathogens on vectors may be direct or indirect, with indirect effects mediated by increases in host quality or reductions in the vulnerability of vectors to natural enemies. We investigated whether the bird cherry-oat aphid Rhopalosiphum padi, a vector of cereal yellow dwarf virus (CYDV) in wheat, experiences a reduction in rates of attack by the parasitoid wasp Aphidius colemani when actively harboring the plant pathogen. We manipulated the vector status of aphids (virus carrying or virus free) and evaluated the impact on the rate of attack by wasps. We found that vector status did not influence the survival or fecundity of aphids in the absence of parasitoids. However, virus-carrying aphids experienced higher rates of parasitism and greater overall population suppression by parasitoid wasps than virus-free aphids. Moreover, virus-carrying aphids were accepted as hosts by wasps more often than virus-free aphids, with a greater number of wasps stinging virus-carrying aphids following assessment by antennal palpations than virus-free aphids. Therefore, counter to the prevailing idea that persistent vector-borne pathogens enhance the performance of their vectors, we found that infectious aphids actively carrying a plant pathogen experience greater vulnerability to natural enemies. Our results suggest that parasitoids may contribute to the successful biological control of CYDV by disproportionately impacting virus-carrying vectors, and thus reducing the proportion of vectors in the population that are infectious.

  11. Abundance of epigaeic arthropods in a Brazilian savanna under different fire frequencies

    Directory of Open Access Journals (Sweden)

    Marcio Uehara-Prado

    2010-10-01

    Full Text Available Fire is a major determinant of structure and dynamics in savannas, and the rapid increase of human activities in this biome has changed the natural burning regime. The effects of fire on the fauna of the cerrado (Brazilian savanna are still poorly understood, and studies comparing sites frequently and infrequently burned are scarce. In this study, the abundance of epigaeic arthropod orders and trophic guilds was assessed in cerrado sites located in the Brazilian Central Plateau that were subjected to three burning frequencies: frequent (HighFi, intermediary (MidFi, and infrequent (LowFi. In general, we found a positive relationship between the abundance of epigaeic arthropods and fire frequency. When arthropods were analyzed by orders, the abundance of Collembola and Orthoptera was lower in the LowFi site, while for Hemiptera, it was higher in the MidFi site. No significant differences were found for Hymenoptera, Coleoptera, and Araneae. The abundance of detritivores and herbivores decreased from HighFi to LowFi, but did not change significantly for omnivores and predators. These results indicate that some arthropod groups may not only be resilient to fire effects, but actually might benefit from fire effects in the cerrado. Characterizing arthropod responses to burning frequency at high taxonomic or functional levels is important for applied studies. Based on the results of the current study, springtails and ants seem to be particularly appropriate focal groups for further exploratory studies on the effects of fire at the species level.

  12. Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods.

    Science.gov (United States)

    Zou, Yi; van Telgen, Mario D; Chen, Junhui; Xiao, Haijun; de Kraker, Joop; Bianchi, Felix J J A; van der Werf, Wopke

    2016-01-01

    Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure, application of this sampling device provides absolute estimates of the populations of arthropods as numbers per standardized sampling area. The sampling efficiency depends critically on the sampling duration. In a mature rice crop, a two-minute sampling in an enclosure of 0.13 m(2) yields more than 90% of the arthropod population. The device also allows sampling of arthropods dwelling on the water surface or the soil in rice paddies, but it is not suitable for sampling fast flying insects, such as predatory Odonata or larger hymenopterous parasitoids. The modified blower-vac is simple to construct, and cheaper and easier to handle than traditional suction sampling devices, such as D-vac. The low cost makes the modified blower-vac also accessible to researchers in developing countries. PMID:27584040

  13. Evaluation of Ground Arthropod Structure in Restoration Area of Talangagung Landfill as Edutourism Attraction, Kepanjen, Malang

    Directory of Open Access Journals (Sweden)

    Dinda Azalia

    2015-09-01

    Full Text Available Aim of this research is to know the composition, community structure and survivality of ground arthropod in restoration area of Talangagung edutourism landfill (TPA Wisata Edukasi Talangagung. Arthopod survey was conducted with four methods, yellow pan trap, pit fall trap, berlesetullgren, and sweep net. The research was done in four different locations with twice repetition. Survey location was devided in three zone, which is zone one with 10 years restoration, zone two with five years restoration, and zone three which not yet restored, and reference site. Abiotic factor which observed in this research such as light intensity, humidity, and air temperature. Analysis of arthropod diversity and community structure in each site was calculated from importance value index (IVI and diversity index (Shannon Wienner Index. The results show that diversity of ground arthropod in zone one, two, three, and reference site was on medium level which each score 1.9, 1.87, 1.71, and 2.08. Community structure with dominant pattern showed with IVI from Acrididae in zone one and zone three with IVI 67.2 % and 53.5 %. Myrmicidae in reference site dominance with IVI 51.4 % and Formicidae in zone one with IVI 48.6 %. Ground arthropod in zone one and reference site had similarity in community structure which showed in same cluster in biplot analysis and zone two and three was in another different cluster. Keywords : Arthropod, diversity, restoration, community structure

  14. Disturbance and recovery of salt marsh arthropod communities following BP Deepwater Horizon oil spill.

    Directory of Open Access Journals (Sweden)

    Brittany D McCall

    Full Text Available Oil spills represent a major environmental threat to coastal wetlands, which provide a variety of critical ecosystem services to humanity. The U.S. Gulf of Mexico is a hub of oil and gas exploration activities that historically have impacted intertidal habitats such as salt marsh. Following the BP Deepwater Horizon oil spill, we sampled the terrestrial arthropod community and marine invertebrates found in stands of Spartina alterniflora, the most abundant plant in coastal salt marshes. Sampling occurred in 2010 as oil was washing ashore and a year later in 2011. In 2010, intertidal crabs and terrestrial arthropods (insects and spiders were suppressed by oil exposure even in seemingly unaffected stands of plants; however, Littoraria snails were unaffected. One year later, crab and arthropods had largely recovered. Our work is the first attempt that we know of assessing vulnerability of the salt marsh arthropod community to oil exposure, and it suggests that arthropods are both quite vulnerable to oil exposure and quite resilient, able to recover from exposure within a year if host plants remain healthy.

  15. Implicit Real Vector Automata

    Directory of Open Access Journals (Sweden)

    Jean-François Degbomont

    2010-10-01

    Full Text Available This paper addresses the symbolic representation of non-convex real polyhedra, i.e., sets of real vectors satisfying arbitrary Boolean combinations of linear constraints. We develop an original data structure for representing such sets, based on an implicit and concise encoding of a known structure, the Real Vector Automaton. The resulting formalism provides a canonical representation of polyhedra, is closed under Boolean operators, and admits an efficient decision procedure for testing the membership of a vector.

  16. Selectively Balancing Unit Vectors

    OpenAIRE

    Blokhuis, Aart; Chen, Hao

    2016-01-01

    A set $U$ of unit vectors is selectively balancing if one can find two disjoint subsets $U^+$ and $U^-$, not both empty, such that the Euclidean distance between the sum of $U^+$ and the sum of $U^-$ is smaller than $1$. We prove that, to guarantee a selectively balancing set, $n \\log n$ unit vectors suffice for sufficiently large $n$, but $\\tfrac{1}{23} n \\log n$ unit vectors won't be enough for infinitely many $n$.

  17. Custodial vector model

    DEFF Research Database (Denmark)

    Becciolini, Diego; Franzosi, Diogo Buarque; Foadi, Roshan;

    2015-01-01

    We analyze the Large Hadron Collider (LHC) phenomenology of heavy vector resonances with a $SU(2)_L\\times SU(2)_R$ spectral global symmetry. This symmetry partially protects the electroweak S-parameter from large contributions of the vector resonances. The resulting custodial vector model spectrum...... and interactions with the standard model fields lead to distinct signatures at the LHC in the diboson, dilepton and associated Higgs channels....

  18. Vectors and their applications

    CERN Document Server

    Pettofrezzo, Anthony J

    2005-01-01

    Geared toward undergraduate students, this text illustrates the use of vectors as a mathematical tool in plane synthetic geometry, plane and spherical trigonometry, and analytic geometry of two- and three-dimensional space. Its rigorous development includes a complete treatment of the algebra of vectors in the first two chapters.Among the text's outstanding features are numbered definitions and theorems in the development of vector algebra, which appear in italics for easy reference. Most of the theorems include proofs, and coordinate position vectors receive an in-depth treatment. Key concept

  19. Symbolic computer vector analysis

    Science.gov (United States)

    Stoutemyer, D. R.

    1977-01-01

    A MACSYMA program is described which performs symbolic vector algebra and vector calculus. The program can combine and simplify symbolic expressions including dot products and cross products, together with the gradient, divergence, curl, and Laplacian operators. The distribution of these operators over sums or products is under user control, as are various other expansions, including expansion into components in any specific orthogonal coordinate system. There is also a capability for deriving the scalar or vector potential of a vector field. Examples include derivation of the partial differential equations describing fluid flow and magnetohydrodynamics, for 12 different classic orthogonal curvilinear coordinate systems.

  20. Community diversity of mosquitoes and their microbes across different habitats endemic for West Nile Virus and other arthropod-borne diseases

    Science.gov (United States)

    Liu, R.; Bennett, S. N.; Thongsripong, P.; Chandler, J. S.

    2013-12-01

    Mosquitoes have long been vectors for disease, and humans, birds, and other vertebrates have served their role as hosts in the transmission cycle of arthropod-borne viruses. In California, there are several mosquito species that act as vectors, transmitting such disease agents as Western equine and St. Louis encephalitis viruses, filarial nematodes, Plasmodium (which causes malaria), and West Nile virus (WNV). Last year (2012-2013), California had over 450 reported cases of West Nile Virus in humans (http://westnile.ca.gov/). To begin to understand mosquitoes and their role in the bay area as vectors of diseases, including West Nile Virus, we trapped mosquitoes from various sites and examined their microbiomes, including bacteria, fungi, viruses, and eukaryotes. Study sites were in Marin, San Mateo, and San Francisco counties, in areas that represented, respectively, rural, suburban, and urban habitats. The mosquitoes were identified through morphological characteristics, and verified molecularly by sequencing of the cytochrome oxidase I (COI) gene extracted from a leg. Most mosquitoes were collected from San Mateo and Mill Valley and were identified as Culiseta incidens. Data from traditional culture-based and next-generation 454 sequencing methods applied to mosquito whole bodies, representing their microbiomes, will be discussed, to determine how mosquito and microbial diversity varies across sites sampled in the San Francisco Bay area.

  1. Tiny individuals attached to a new Silurian arthropod suggest a unique mode of brood care

    Science.gov (United States)

    Briggs, Derek E. G.; Siveter, Derek J.; Siveter, David J.; Sutton, Mark D.

    2016-04-01

    The ˜430-My-old Herefordshire, United Kingdom, Lagerstätte has yielded a diversity of remarkably preserved invertebrates, many of which provide fundamental insights into the evolutionary history and ecology of particular taxa. Here we report a new arthropod with 10 tiny arthropods tethered to its tergites by long individual threads. The head of the host, which is covered by a shield that projects anteriorly, bears a long stout uniramous antenna and a chelate limb followed by two biramous appendages. The trunk comprises 11 segments, all bearing limbs and covered by tergites with long slender lateral spines. A short telson bears long parallel cerci. Our phylogenetic analysis resolves the new arthropod as a stem-group mandibulate. The evidence suggests that the tethered individuals are juveniles and the association represents a complex brooding behavior. Alternative possibilities—that the tethered individuals represent a different epizoic or parasitic arthropod—appear less likely.

  2. A framework for assessment and monitoring of arthropods in a lowland tropical forest.

    Science.gov (United States)

    Finnamore, Albert; Alonso, Alfonso; Santisteban, Jose; Cordova, Saida; Valencia, Gorky; de la Cruz, Alicia; Polo, Roberto

    2002-05-01

    By applying principles of adaptive management, and by using the valuable information that arthropods provide from assessment and monitoring programs, managers can identify and reduce possible impacts on biodiversity in development projects. In 1996, the Smithsonian Institution's Monitoring and Assessment of Biodiversity program worked together with Shell Prospecting and Development Peru to establish an adaptive management program to protect biodiversity in a natural gas exploration project in a Peruvian rainforest. In this paper, we outlined the conceptual steps involved in establishing an assessment and monitoring program for arthropods, including setting objectives, evaluating the results and making decisions. We also present the results of the assessment using some of groups of arthropods, and summarize the steps taken to identify appropriate groups for monitoring. PMID:12125749

  3. Spatial dynamics of understorey insectivorous birds and arthropods in a southeastern Brazilian Atlantic woodlot.

    Science.gov (United States)

    Manhães, M A; Dias, M M

    2011-02-01

    Spatial distribution and spatial relationships in capture rates of understorey insectivorous birds and density of arthropods were investigated in a patch of upper montane rain forest in Minas Gerais state, southeastern Brazil, from January to December 2004. The composition of the arthropod fauna collected was similar to that reported for other tropical forests, with predominance of Araneae, Coleoptera, Hymenoptera and Hemiptera non-Heteroptera. A total of 26 bird species were captured, among which the more common were Dysithamnus mentalis, Conopophaga lineata, Platyrinchus mystaceus, Basileuterus culicivorus and Sclerurus scansor. Variation in the bird capture rates among sampling net lines were not correlated with arthropod density. Rather, individual analyses of some bird species suggest that spatial distribution of understorey insectivorous birds is better explained by habitat type. PMID:21437393

  4. Responsiveness of arthropod herbivores and their natural enemies to modified weed management in corn.

    Science.gov (United States)

    Albajes, Ramon; Lumbierres, Belén; Pons, Xavier

    2009-06-01

    Alteration of weed flora as consequence of the deployment of genetically modified herbicide-tolerant crops may affect higher trophic levels in agrosystems. A 4-yr study is being conducted in Spain to investigate interrelations between weeds and associated arthropods in corn fields. In a first step, the work aimed to detect the most responsive arthropods to weed management changes. To identify the most responsive arthropods, arthropod composition and abundance in herbicide-tolerant corn plots treated twice with glyphosate and untreated plots were compared for 2 yr. Plots were sampled seven times during the season by visual inspection and pitfall and yellow sticky traps to estimate abundance and activity of the main arthropod herbivores, predators, and parasitoids. As intended, the abundance and composition of weed flora was strongly altered by the differential herbicide treatments. Several groups of arthropods responded to the weed changes but in variable directions. Whereas leafhoppers and aphids were more abundant on herbicide-treated plots, the contrary was found for phytophagous thrips. Among predators, Orius sp., spiders, and trombidids were more abundant on treated plots, whereas nabids and carabids were more abundant in untreated plots; the same case was found for carabids and spiders caught in pitfall traps. Among parasitoids, ichneumonids were more abundant in untreated plots and mymarids in treated plots. These results cannot be interpreted in terms of nontarget effects of postemergence treatments with broad-spectrum herbicides; for this, a comparison with conventional weed management practices should be done and this is the current step in the study. PMID:19508806

  5. Isomin: a novel cytoplasmic intermediate filament protein from an arthropod species

    Directory of Open Access Journals (Sweden)

    Lupetti Pietro

    2011-02-01

    Full Text Available Abstract Background The expression of intermediate filaments (IFs is a hallmark feature of metazoan cells. IFs play a central role in cell organization and function, acting mainly as structural stress-absorbing elements. There is growing evidence to suggest that these cytoskeletal elements are also involved in the integration of signalling networks. According to their fundamental functions, IFs show a widespread phylogenetic expression, from simple diblastic animals up to mammals, and their constituent proteins share the same molecular organization in all species so far analysed. Arthropods represent a major exception in this scenario. Only lamins, the nuclear IF proteins, have so far been identified in the model organisms analysed; on this basis, it has been considered that arthropods do not express cytoplasmic IFs. Results Here, we report the first evidence for the expression of a cytoplasmic IF protein in an arthropod - the basal hexapod Isotomurus maculatus. This new protein, we named it isomin, is a component of the intestinal terminal web and shares with IFs typical biochemical properties, molecular features and reassembly capability. Sequence analysis indicates that isomin is mostly related to the Intermediate Filament protein C (IFC subfamily of Caenorhabditis elegans IF proteins, which are molecular constituents of the nematode intestinal terminal web. This finding is coherent with, and provides further support to, the most recent phylogenetic views of arthropod ancestry. Interestingly, the coil 1a domain of isomin appears to have been influenced by a substantial molecular drift and only the aminoterminal part of this domain, containing the so-called helix initiation motif, has been conserved. Conclusions Our results set a new basis for the analysis of IF protein evolution during arthropod phylogeny. In the light of this new information, the statement that the arthropod phylum lacks cytoplasmic IFs is no longer tenable. See commentary

  6. Elevated atmospheric CO2 alters the arthropod community in a forest understory

    Science.gov (United States)

    Hamilton, Jason; Zangerl, Arthur R.; Berenbaum, May R.; Sparks, Jed P.; Elich, Lauren; Eisenstein, Alissa; DeLucia, Evan H.

    2012-08-01

    The objective of this study was to determine the extent to which overall population sizes and community composition of arthropods in a naturally occurring forest understory are altered by elevated CO2. The Free Air Concentration Enrichment (FACE) method was used to fumigate large, replicated plots in the Piedmont region of North Carolina, USA to achieve the CO2 concentration predicted for 2050 (˜580 μl l-1). In addition, the extent to which unrestricted herbivorous arthropods were spatially delimited in their resource acquisition was determined. Stable isotope data for spiders (δ13C and δ15N) were collected in ambient and elevated CO2 plots and analyzed to determine whether their prey species moved among plots. Elevated CO2 had no effect on total arthropod numbers but had a large effect on the composition of the arthropod community. Insects collected in our samples were identified to a level that allowed for an assignment of trophic classification (generally to family). For the groups of insects sensitive to atmospheric gas composition, there was an increase in the numbers of individuals collected in primarily predaceous orders (Araneae and Hymenoptera; from 60% to more than 150%) under elevated CO2 and a decrease in the numbers in primarily herbivorous orders (Lepidoptera and Coleoptera; from -30 to -45%). Isotopic data gave no indication that the treatment plots represented a "boundary" to the movement of insects or that there were distinct and independent insect populations inside and outside the treatment plots. A simple two-ended mixing model estimates 55% of the carbon and nitrogen in spider biomass originated external to the elevated CO2 plots. In addition to changes in insect performance, decreases in herbivorous arthropods and increases in predaceous arthropods may also be factors involved in reduced herbivory under elevated CO2 in this forest.

  7. Habitat Heterogeneity Affects Plant and Arthropod Species Diversity and Turnover in Traditional Cornfields.

    Science.gov (United States)

    Martínez, Eliana; Rös, Matthias; Bonilla, María Argenis; Dirzo, Rodolfo

    2015-01-01

    The expansion of the agricultural frontier by the clearing of remnant forests has led to human-dominated landscape mosaics. Previous studies have evaluated the effect of these landscape mosaics on arthropod diversity at local spatial scales in temperate and tropical regions, but little is known about fragmentation effects in crop systems, such as the complex tropical traditional crop systems that maintain a high diversity of weeds and arthropods in low-Andean regions. To understand the factors that influence patterns of diversity in human-dominated landscapes, we investigate the effect of land use types on plant and arthropod diversity in traditionally managed cornfields, via surveys of plants and arthropods in twelve traditional cornfields in the Colombian Andes. We estimated alpha and beta diversity to analyze changes in diversity related to land uses within a radius of 100 m to 1 km around each cornfield. We observed that forests influenced alpha diversity of plants, but not of arthropods. Agricultural lands had a positive relationship with plants and herbivores, but a negative relationship with predators. Pastures positively influenced the diversity of plants and arthropods. In addition, forest cover seemed to influence changes in plant species composition and species turnover of herbivore communities among cornfields. The dominant plant species varied among fields, resulting in high differentiation of plant communities. Predator communities also exhibited high turnover among cornfields, but differences in composition arose mainly among rare species. The crop system evaluated in this study represents a widespread situation in the tropics, therefore, our results can be of broad significance. Our findings suggest that traditional agriculture may not homogenize biological communities, but instead could maintain the regional pool of species through high beta diversity. PMID:26197473

  8. Habitat Heterogeneity Affects Plant and Arthropod Species Diversity and Turnover in Traditional Cornfields.

    Directory of Open Access Journals (Sweden)

    Eliana Martínez

    Full Text Available The expansion of the agricultural frontier by the clearing of remnant forests has led to human-dominated landscape mosaics. Previous studies have evaluated the effect of these landscape mosaics on arthropod diversity at local spatial scales in temperate and tropical regions, but little is known about fragmentation effects in crop systems, such as the complex tropical traditional crop systems that maintain a high diversity of weeds and arthropods in low-Andean regions. To understand the factors that influence patterns of diversity in human-dominated landscapes, we investigate the effect of land use types on plant and arthropod diversity in traditionally managed cornfields, via surveys of plants and arthropods in twelve traditional cornfields in the Colombian Andes. We estimated alpha and beta diversity to analyze changes in diversity related to land uses within a radius of 100 m to 1 km around each cornfield. We observed that forests influenced alpha diversity of plants, but not of arthropods. Agricultural lands had a positive relationship with plants and herbivores, but a negative relationship with predators. Pastures positively influenced the diversity of plants and arthropods. In addition, forest cover seemed to influence changes in plant species composition and species turnover of herbivore communities among cornfields. The dominant plant species varied among fields, resulting in high differentiation of plant communities. Predator communities also exhibited high turnover among cornfields, but differences in composition arose mainly among rare species. The crop system evaluated in this study represents a widespread situation in the tropics, therefore, our results can be of broad significance. Our findings suggest that traditional agriculture may not homogenize biological communities, but instead could maintain the regional pool of species through high beta diversity.

  9. Cosmology with vector distortion

    CERN Document Server

    Jimenez, Jose Beltran

    2016-01-01

    We consider an extension of Weyl geometry with the most general connection linearly determined by a vector field. We discuss some of the geometrical properties within this framework and then we construct gravitational theories leading to an interesting class of vector-tensor theories with cosmological applications.

  10. Switched Multistage Vector Quantizer

    Directory of Open Access Journals (Sweden)

    M Satya Sai Ram

    2010-01-01

    Full Text Available This paper investigates the use of a new hybrid vector quantizer called Switched Multi stage vector quantization (SWMSVQ technique using hard and soft decision schemes, for coding of narrow band speech signals. This technique is a hybrid of Switch vector quantization technique and Multi stage vector quantization technique. SWMSVQ quantizes the linear predictive coefficients (LPC in terms of the line spectral frequencies (LSF. The spectral distortion performance, computational complexity and memory requirements of SWMSVQ using hard and soft decision schemes are compared with Split vector quantization (SVQ technique, Multi stage vector quantization (MSVQ technique, Switched Split vector quantization (SSVQ technique using hard decision scheme, and Multi Switched Split Vector quantization (MSSVQ technique using hard decision scheme. From results it is proved that SWMSVQ using soft decision scheme is having less spectral distortion, computational complexity and memory requirements when compared to SVQ, MSVQ, SSVQ and SWMSVQ using hard decision scheme, but high when compared to MSSVQ using hard decision scheme. So from results it is proved that SWMSVQ using soft decision scheme is better when compared to SVQ, MSVQ, SSVQ and SWMSVQ using hard decision schemes in terms of spectral distortion, computational complexity and memory requirements but is having greater spectral distortion, computational complexity and memory requirements when compared to MSSVQ using hard decision.

  11. Community Composition and Structure of Soil Macro-Arthropods Under Agricultural Land Uses in the Black Soil Region of Jilin Province, China

    Institute of Scientific and Technical Information of China (English)

    WU Dong-hui; ZHANG Bai; CHEN Peng

    2006-01-01

    Soil macro-arthropods in the black soil region in Jilin Province of China were investigated with the emphasis laid on the species richness and abundance in relation to the types of land-use, i.e., farm yard, farm land and Three-North Forest Shelter Belt. Soil macro-arthropods were hand-sorted in the field. A total of 2 357 soil macro-arthropod individuals was captured and fell into 70 families. The results suggested that type of land use affected the species richness and abundance of soil macro-arthropods. Agricultural practices had a strong impact on the soil macro-arthropods community, the conventional cultivations changed the vertical structure of macro-arthropods in the soil profile, and improved the richness and abundance of macro-arthropods in the lower soil layers especially in July. The results also showed that different groups of soil macro-arthropods had various responses to land use changes.

  12. Spatial distribution and internal metal concentrations of terrestrial arthropods in a moderately contaminated lowland floodplain along the Rhine River

    Energy Technology Data Exchange (ETDEWEB)

    Schipper, Aafke M. [Department of Environmental Science, Institute for Wetland and Water Research, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands)], E-mail: a.schipper@science.ru.nl; Wijnhoven, Sander [Centre for Sustainable Management of Resources, Institute for Science, Innovation and Society, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Netherlands Institute of Ecology, Centre for Estuarine and Marine Ecology, Monitor Taskforce, P.O. Box 140, 4400 AC Yerseke (Netherlands); Leuven, Rob S.E.W.; Ragas, Ad M.J.; Jan Hendriks, A. [Department of Environmental Science, Institute for Wetland and Water Research, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands)

    2008-01-15

    Soil metal concentrations, inundation characteristics and abundances of 14 arthropod taxa were investigated in a moderately contaminated lowland floodplain along the Rhine River and compared to the hinterland. Internal metal concentrations were determined for the orders of Coleoptera (beetles) and Araneida (spiders) and were related to soil concentrations. The floodplain was characterized by larger arthropod abundance than the hinterland, in spite of recurrent inundations and higher soil metal concentrations. Most arthropod taxa showed increasing abundance with decreasing distance to the river channel and increasing average inundation duration. For Cd, Cu, Pb and Zn, significant relations were found between arthropod concentrations and concentrations in soil. Significant relations were few but positive, indicating that increasing soil concentrations result in increasing body burdens in arthropods. For arthropod-eating vertebrates, these results might imply that larger prey availability in the floodplain coincides with higher metal concentrations in prey, possibly leading to increased exposure to metal contamination. - Recurrent floodplain inundations affect terrestrial arthropod numbers and metal contamination levels.

  13. The first myriapod genome sequence reveals conservative arthropod gene content and genome organisation in the centipede Strigamia maritima

    NARCIS (Netherlands)

    Chipman, Ariel D; Ferrier, David E K; Brena, Carlo; Qu, Jiaxin; Hughes, Daniel S T; Schröder, Reinhard; Torres-Oliva, Montserrat; Znassi, Nadia; Jiang, Huaiyang; Almeida, Francisca C; Alonso, Claudio R; Apostolou, Zivkos; Aqrawi, Peshtewani; Arthur, Wallace; Barna, Jennifer C J; Blankenburg, Kerstin P; Brites, Daniela; Capella-Gutiérrez, Salvador; Coyle, Marcus; Dearden, Peter K; Du Pasquier, Louis; Duncan, Elizabeth J; Ebert, Dieter; Eibner, Cornelius; Erikson, Galina; Evans, Peter D; Extavour, Cassandra G; Francisco, Liezl; Gabaldón, Toni; Gillis, William J; Goodwin-Horn, Elizabeth A; Green, Jack E; Griffiths-Jones, Sam; Grimmelikhuijzen, Cornelis J P; Gubbala, Sai; Guigó, Roderic; Han, Yi; Hauser, Frank; Havlak, Paul; Hayden, Luke; Helbing, Sophie; Holder, Michael; Hui, Jerome H L; Hunn, Julia P; Hunnekuhl, Vera S; Jackson, LaRonda; Javaid, Mehwish; Jhangiani, Shalini N; Jiggins, Francis M; Jones, Tamsin E; Kaiser, Tobias S; Kalra, Divya; Kenny, Nathan J; Korchina, Viktoriya; Kovar, Christie L; Kraus, F Bernhard; Lapraz, François; Lee, Sandra L; Lv, Jie; Mandapat, Christigale; Manning, Gerard; Mariotti, Marco; Mata, Robert; Mathew, Tittu; Neumann, Tobias; Newsham, Irene; Ngo, Dinh N; Ninova, Maria; Okwuonu, Geoffrey; Ongeri, Fiona; Palmer, William J; Patil, Shobha; Patraquim, Pedro; Pham, Christopher; Pu, Ling-Ling; Putman, Nicholas H; Rabouille, Catherine; Ramos, Olivia Mendivil; Rhodes, Adelaide C; Robertson, Helen E; Robertson, Hugh M; Ronshaugen, Matthew; Rozas, Julio; Saada, Nehad; Sánchez-Gracia, Alejandro; Scherer, Steven E; Schurko, Andrew M; Siggens, Kenneth W; Simmons, DeNard; Stief, Anna; Stolle, Eckart; Telford, Maximilian J; Tessmar-Raible, Kristin; Thornton, Rebecca; van der Zee, Maurijn; von Haeseler, Arndt; Williams, James M; Willis, Judith H; Wu, Yuanqing; Zou, Xiaoyan; Lawson, Daniel; Muzny, Donna M; Worley, Kim C; Gibbs, Richard A; Akam, Michael; Richards, Stephen

    2014-01-01

    Myriapods (e.g., centipedes and millipedes) display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We present

  14. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants

    Science.gov (United States)

    Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages. PMID:26731271

  15. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants.

    Directory of Open Access Journals (Sweden)

    Julieta Benítez-Malvido

    Full Text Available Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages.

  16. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants.

    Science.gov (United States)

    Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages.

  17. Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants

    Science.gov (United States)

    This paper provides recommendations on experimental design for early-tier laboratory studies used in the risk assessment process to evaluate potential adverse impacts of arthropod-resistant genetically-engineered plants on non-target arthropods. While we rely heavily on the currently used proteins f...

  18. Deriving criteria to select arthropod species for laboratory tests to assess the ecological risks from cultivating transgenic crops

    Science.gov (United States)

    Arthropods form a major part of the biodiversity in agricultural landscapes. Many species are valued because they provide ecosystem services, including biological control, pollination, and decomposition, or because they are valued for cultural or economic reasons. Some arthropods reduce crop yield a...

  19. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants.

    Science.gov (United States)

    Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages. PMID:26731271

  20. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...

  1. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...... of parameter spaces into structurally stable domains, and a description of the bifurcations. For this reason, the talk will focus on these questions for complex polynomial vector fields....

  2. The response of sward-dwelling arthropod communities to reduced grassland management intensity in pastures

    Directory of Open Access Journals (Sweden)

    Helden Alvin J.

    2015-12-01

    Full Text Available We compared arthropod taxon richness, diversity and community structure of two replicated grassland husbandry experiments to investigate effects of reduced management intensity, as measured by nutrient input levels (390, 224 and 0 kg/ha per year N in one experiment, and 225 and 88 kg/ha per year N in another. Suction sampling was used to collect Araneae, Coleoptera, Hemiptera and Hymenoptera, with Araneae and Coleoptera also sampled with pitfall trapping. Univariate analyses found no significant differences in abundance and species density between treatments. However, with multivariate analysis, there were significant differences in arthropod community structure between treatments in both experiments.

  3. Experimental Manipulation of Grassland Plant Diversity Induces Complex Shifts in Aboveground Arthropod Diversity.

    Science.gov (United States)

    Hertzog, Lionel R; Meyer, Sebastian T; Weisser, Wolfgang W; Ebeling, Anne

    2016-01-01

    Changes in producer diversity cause multiple changes in consumer communities through various mechanisms. However, past analyses investigating the relationship between plant diversity and arthropod consumers focused only on few aspects of arthropod diversity, e.g. species richness and abundance. Yet, shifts in understudied facets of arthropod diversity like relative abundances or species dominance may have strong effects on arthropod-mediated ecosystem functions. Here we analyze the relationship between plant species richness and arthropod diversity using four complementary diversity indices, namely: abundance, species richness, evenness (equitability of the abundance distribution) and dominance (relative abundance of the dominant species). Along an experimental gradient of plant species richness (1, 2, 4, 8, 16 and 60 plant species), we sampled herbivorous and carnivorous arthropods using pitfall traps and suction sampling during a whole vegetation period. We tested whether plant species richness affects consumer diversity directly (i), or indirectly through increased productivity (ii). Further, we tested the impact of plant community composition on arthropod diversity by testing for the effects of plant functional groups (iii). Abundance and species richness of both herbivores and carnivores increased with increasing plant species richness, but the underlying mechanisms differed between the two trophic groups. While higher species richness in herbivores was caused by an increase in resource diversity, carnivore richness was driven by plant productivity. Evenness of herbivore communities did not change along the gradient in plant species richness, whereas evenness of carnivores declined. The abundance of dominant herbivore species showed no response to changes in plant species richness, but the dominant carnivores were more abundant in species-rich plant communities. The functional composition of plant communities had small impacts on herbivore communities, whereas

  4. Background internal dose rates of earthworm and arthropod species in the forests of Aomori, Japan

    International Nuclear Information System (INIS)

    In this study, we measured the concentrations of several natural radionuclides in samples of one earthworm species and 11 arthropod species collected from four coniferous forests in Rokkasho, Aomori Prefecture, Japan, and we assessed the background internal radiation dose rate for each species. Dose rates were calculated by using the radionuclide concentrations in the samples and dose conversion coefficients obtained from the literature. The mean internal dose rate in the earthworm species was 0.28 μGy h-1, and the mean internal dose rates in the arthropod species ranged between 0.036 and 0.69 μGy h-1. (author)

  5. [Alpha and beta arthropods diversity from the different environments of Parque Nacional Los Cardones, Salta, Argentina].

    Science.gov (United States)

    Belén Cava, Maria; Antonio Corronca, José; José Echeverría, Alejandro

    2013-12-01

    The essential role of the National Parks is to protect nature, in order to prevent the deterioration and loss of the ecosystem under protection. Very few records about the diversity of arthropods are known from Los Cardones National Park, where three eco-regions are protected: Puna and Monte eco-regions and the High Andean Grassland of the Yungas. Here, we aimed to compare the alpha and beta diversity of arthropods in these eco-regions, and to prove if sites from the same ecoregion, show greater similarity between them in their assemblages, than with sites of the other eco-regions. We also identified arthropod orders with higher species richness, and indicated the families that contribute the most to the registered beta diversity. Three sampling sites were established on each eco-region and the arthropods were sampled using pitfall traps and suction samples. We evaluated the obtained inventory through nonparametric estimators of species richness, and compared diversity among eco-regions through "diversity profiles" and "effective number of species". Beta diversity was assessed by different methods such as the Morisita Index, nonmetric multidimentional scaling analysis, a multiple permutation procedure, and a Similarity Percentage analysis. We recorded 469 spp/morphospecies and recognized three arthropod orders (spiders, dipterans and hymenopterans) that are diverse and abundant in the Park. Besides, the diversity in Los Cardones National Park was found to be high, but it was observed higher in the High Andean Grassland of the Yungas, and lower in the Puna. The inventory obtained was good, reached up to the 81% of the species richness estimated by nonparametric estimators. Each eco-region of the park showed a very particular arthropod community that was tested by a multi-response permutation procedure. The species turnover between eco-regions was high, so that the different environments of the protected area are contributing to the maintenance of the regional

  6. [Vector transmitted diseases and climate changes in Europe].

    Science.gov (United States)

    Rossati, Antonella; Bargiacchi, Olivia; Kroumova, Vesselina; Garavelli, Pietro Luigi

    2014-09-01

    The increase in temperatures recorded since the mid-nineteenth century is unprecedented in the history of mankind. The consequences of climate changes are numerous and can affect human health through direct (extreme events, natural disasters) or indirect (alteration of the ecosystem) mechanisms. Climate changes have repercussions on ecosystems, agriculture, social conditions, migration, conflicts and the transmission mode of infectious diseases. Vector-borne diseases are infections transmitted by the bite of infected arthropods such as mosquitoes, ticks, triatomines, sand flies and flies. Epidemiological cornerstones of vector-borne diseases are: the ecology and behaviour of the host, the ecology and behaviour of the vector, and the population's degree of immunity. Mosquito vectors related to human diseases mainly belong to the genus Culex, Aedes and Mansonia. Climate changes in Europe have increased the spread of new vectors, such as Aedes albopictus, and in some situations have made it possible to sustain the autochthonous transmission of some diseases (outbreak of Chukungunya virus in northern Italy in 2007, cases of dengue in the South of France and in Croatia). Despite the eradication of malaria from Europe, anopheline carriers are still present, and they may allow the transmission of the disease if the climatic conditions favour the development of the vectors and their contacts with plasmodium carriers. The tick Ixodes ricinus is a vector whose expansion has been documented both in latitude and in altitude in relation to the temperature increase; at the same time the related main viral and bacterial infections have increased. In northern Italy and Germany, the appearance of Leishmaniasis has been associated to climatic conditions that favour the development of the vector Phlebotomus papatasi and the maturation of the parasite within the vector, although the increase of cases of visceral leishmaniasis is also related to host immune factors, particularly

  7. Line Integral of a Vector.

    Science.gov (United States)

    Balabanian, Norman

    This programed booklet is designed for the engineering student who understands and can use vector and unit vector notation, components of a vector, parallel law of vector addition, and the dot product of two vectors. Content begins with work done by a force in moving a body a certain distance along some path. For each of the examples and problem…

  8. Review of available evidence regarding the vulnerability of off-crop non-target arthropod communities in comparison to in-crop non-target arthropod communities

    OpenAIRE

    Lange, de, E.C.M.; Lahr, J.; Brouwer, J.H.D.; Faber, J. H.

    2012-01-01

    EFSA is revising and updating the Ecotoxicology Guidance Document on Terrestrial Risk Assessment of Pesticides (SANCO/10329/2002). For this purpose an overview of available scientific information on several topics is needed. The aim of the current literature survey was to collect and summarize the published scientific literature on (1) the composition of non-target arthropod species that occur in and outside crops, (2) their vulnerability to pesticides and (3) their potential to recover from ...

  9. Biological Control of Mosquito Vectors: Past, Present, and Future

    Directory of Open Access Journals (Sweden)

    Giovanni Benelli

    2016-10-01

    Full Text Available Mosquitoes represent the major arthropod vectors of human disease worldwide transmitting malaria, lymphatic filariasis, and arboviruses such as dengue virus and Zika virus. Unfortunately, no treatment (in the form of vaccines or drugs is available for most of these diseases andvectorcontrolisstillthemainformofprevention. Thelimitationsoftraditionalinsecticide-based strategies, particularly the development of insecticide resistance, have resulted in significant efforts to develop alternative eco-friendly methods. Biocontrol strategies aim to be sustainable and target a range of different mosquito species to reduce the current reliance on insecticide-based mosquito control. In thisreview, weoutline non-insecticide basedstrategiesthat havebeenimplemented orare currently being tested. We also highlight the use of mosquito behavioural knowledge that can be exploited for control strategies.

  10. Future challenges for parasitology: vector control and one health in the Americas.

    Science.gov (United States)

    Little, Susan E

    2013-08-01

    "One Health" is a term that encapsulates and underscores the inherent interrelatedness of the health of people, animals, and the environment. Vector-borne infections are central in one health. Many arthropod vectors readily feed on humans and other animals, serving as an ideal conduit to move pathogens between a wide spectrum of potential hosts. As ecological niches flux, opportunities arise for vectors to interact with novel species, allowing infectious agents to broaden both geographic and host ranges. Habitat change has been linked to the emergence of novel human and veterinary disease agents, and can dramatically facilitate expansion opportunities by allowing existing vector populations to flourish and by supporting the establishment of new pathogen maintenance systems. At the same time, control efforts can be hindered by the development of parasiticide and pesticide resistance, foiling efforts to meet these challenges. Using examples drawn from representative diseases important in one health in the Americas, including rickettsial infections, Lyme borreliosis, Chagas disease, and West Nile virus, this paper reviews key aspects of vector-borne disease maintenance cycles that present challenges for one health in the Americas, including emergence of vector-borne disease agents, the impact of habitat change on vector-borne disease transmission, and the complexities faced in developing effective control programs. Novel strategies will be required to effectively combat these infections in the future if we are to succeed in the goal of fostering an environment which supports healthy animals and healthy people.

  11. Vector species richness increases haemorrhagic disease prevalence through functional diversity modulating the duration of seasonal transmission.

    Science.gov (United States)

    Park, Andrew W; Cleveland, Christopher A; Dallas, Tad A; Corn, Joseph L

    2016-06-01

    Although many parasites are transmitted between hosts by a suite of arthropod vectors, the impact of vector biodiversity on parasite transmission is poorly understood. Positive relationships between host infection prevalence and vector species richness (SR) may operate through multiple mechanisms, including (i) increased vector abundance, (ii) a sampling effect in which species of high vectorial capacity are more likely to occur in species-rich communities, and (iii) functional diversity whereby communities comprised species with distinct phenologies may extend the duration of seasonal transmission. Teasing such mechanisms apart is impeded by a lack of appropriate data, yet could highlight a neglected role for functional diversity in parasite transmission. We used statistical modelling of extensive host, vector and microparasite data to test the hypothesis that functional diversity leading to longer seasonal transmission explained variable levels of disease in a wildlife population. We additionally developed a simple transmission model to guide our expectation of how an increased transmission season translates to infection prevalence. Our study demonstrates that vector SR is associated with increased levels of disease reporting, but not via increases in vector abundance or via a sampling effect. Rather, the relationship operates by extending the length of seasonal transmission, in line with theoretical predictions. PMID:26206418

  12. Genetic Drift, Purifying Selection and Vector Genotype Shape Dengue Virus Intra-host Genetic Diversity in Mosquitoes

    Science.gov (United States)

    Fontaine, Albin; Ar Gouilh, Meriadeg; Moltini-Conclois, Isabelle

    2016-01-01

    Due to their error-prone replication, RNA viruses typically exist as a diverse population of closely related genomes, which is considered critical for their fitness and adaptive potential. Intra-host demographic fluctuations that stochastically reduce the effective size of viral populations are a challenge to maintaining genetic diversity during systemic host infection. Arthropod-borne viruses (arboviruses) traverse several anatomical barriers during infection of their arthropod vectors that are believed to impose population bottlenecks. These anatomical barriers have been associated with both maintenance of arboviral genetic diversity and alteration of the variant repertoire. Whether these patterns result from stochastic sampling (genetic drift) rather than natural selection, and/or from the influence of vector genetic heterogeneity has not been elucidated. Here, we used deep sequencing of full-length viral genomes to monitor the intra-host evolution of a wild-type dengue virus isolate during infection of several mosquito genetic backgrounds. We estimated a bottleneck size ranging from 5 to 42 founding viral genomes at initial midgut infection, irrespective of mosquito genotype, resulting in stochastic reshuffling of the variant repertoire. The observed level of genetic diversity increased following initial midgut infection but significantly differed between mosquito genetic backgrounds despite a similar initial bottleneck size. Natural selection was predominantly negative (purifying) during viral population expansion. Taken together, our results indicate that dengue virus intra-host genetic diversity in the mosquito vector is shaped by genetic drift and purifying selection, and point to a novel role for vector genetic factors in the genetic breadth of virus populations during infection. Identifying the evolutionary forces acting on arboviral populations within their arthropod vector provides novel insights into arbovirus evolution. PMID:27304978

  13. Genetic Drift, Purifying Selection and Vector Genotype Shape Dengue Virus Intra-host Genetic Diversity in Mosquitoes.

    Science.gov (United States)

    Lequime, Sebastian; Fontaine, Albin; Ar Gouilh, Meriadeg; Moltini-Conclois, Isabelle; Lambrechts, Louis

    2016-06-01

    Due to their error-prone replication, RNA viruses typically exist as a diverse population of closely related genomes, which is considered critical for their fitness and adaptive potential. Intra-host demographic fluctuations that stochastically reduce the effective size of viral populations are a challenge to maintaining genetic diversity during systemic host infection. Arthropod-borne viruses (arboviruses) traverse several anatomical barriers during infection of their arthropod vectors that are believed to impose population bottlenecks. These anatomical barriers have been associated with both maintenance of arboviral genetic diversity and alteration of the variant repertoire. Whether these patterns result from stochastic sampling (genetic drift) rather than natural selection, and/or from the influence of vector genetic heterogeneity has not been elucidated. Here, we used deep sequencing of full-length viral genomes to monitor the intra-host evolution of a wild-type dengue virus isolate during infection of several mosquito genetic backgrounds. We estimated a bottleneck size ranging from 5 to 42 founding viral genomes at initial midgut infection, irrespective of mosquito genotype, resulting in stochastic reshuffling of the variant repertoire. The observed level of genetic diversity increased following initial midgut infection but significantly differed between mosquito genetic backgrounds despite a similar initial bottleneck size. Natural selection was predominantly negative (purifying) during viral population expansion. Taken together, our results indicate that dengue virus intra-host genetic diversity in the mosquito vector is shaped by genetic drift and purifying selection, and point to a novel role for vector genetic factors in the genetic breadth of virus populations during infection. Identifying the evolutionary forces acting on arboviral populations within their arthropod vector provides novel insights into arbovirus evolution.

  14. ON VECTOR NETWORK EQUILIBRIUM PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    Guangya CHEN

    2005-01-01

    In this paper we define a concept of weak equilibrium for vector network equilibrium problems.We obtain sufficient conditions of weak equilibrium points and establish relation with vector network equilibrium problems and vector variational inequalities.

  15. Avipoxviruses: infection biology and their use as vaccine vectors

    Directory of Open Access Journals (Sweden)

    Tryland Morten

    2011-02-01

    Full Text Available Abstract Avipoxviruses (APVs belong to the Chordopoxvirinae subfamily of the Poxviridae family. APVs are distributed worldwide and cause disease in domestic, pet and wild birds of many species. APVs are transmitted by aerosols and biting insects, particularly mosquitoes and arthropods and are usually named after the bird species from which they were originally isolated. The virus species Fowlpox virus (FWPV causes disease in poultry and associated mortality is usually low, but in flocks under stress (other diseases, high production mortality can reach up to 50%. APVs are also major players in viral vaccine vector development for diseases in human and veterinary medicine. Abortive infection in mammalian cells (no production of progeny viruses and their ability to accommodate multiple gene inserts are some of the characteristics that make APVs promising vaccine vectors. Although abortive infection in mammalian cells conceivably represents a major vaccine bio-safety advantage, molecular mechanisms restricting APVs to certain hosts are not yet fully understood. This review summarizes the current knowledge relating to APVs, including classification, morphogenesis, host-virus interactions, diagnostics and disease, and also highlights the use of APVs as recombinant vaccine vectors.

  16. Bartonellae in animals and vectors in New Caledonia.

    Science.gov (United States)

    Mediannikov, Oleg; Davoust, Bernard; Cabre, Olivier; Rolain, Jean-Marc; Raoult, Didier

    2011-12-01

    Bartonellae are gram-negative facultative intracellular alpha-proteobacteria from the family Bartonellaceae. The natural history of bartonellae consists of a reservoir/host, which is a vertebrate with chronic intravascular infection with sustained bacteremia, and a vector (usually an arthropod) that transfers the bacteria from the reservoir to a susceptible yet uninfected host. In order to reveal the sources and reservoirs of Bartonella infection in animals and vectors in New Caledonia, we collected the blood samples of 64 dogs, 8 cats, 30 bovines, 25 horses and 29 wild deer Cervus timorensis russa and 308 associated blood-sucking parasites (14 keds Hippobosca equina, 258 ticks (22 Rhipicephalus microplus, 235 Rhipicephalus sanguineus, and 1 Haemaphysalis longicornis), 12 fleas Ctenocephalides felis and 24 dog lice Trichodectes canis). We isolated ten strains of Bartonella: four Bartonella henselae from cats and six Bartonella chomelii from cattle. The strains were characterized by sequencing of five genes (16S, ITS, rpoB, gltA and ftsZ). The six strains isolated from cattle were close to the reference strain of B. chomelii and were, probably, imported from France with cattle of Limousin race. PCR showed that 35% of keds collected from deer and 31% of deer were infected by B. aff. schoenbuchensis; all other samples were negative. Our data confirmed that in New Caledonia, as in other regions of the world, cats are the major reservoirs of B. henselae. We also confirmed that Hippoboscidae flies may serve as the vectors of ruminant-associated bartonellae. PMID:22018646

  17. Relationships between dead wood and arthropods in the Southeastern United States.

    Energy Technology Data Exchange (ETDEWEB)

    Ulyshen, Michael, Darragh

    2009-05-01

    The importance of dead wood to maintaining forest diversity is now widely recognized. However, the habitat associations and sensitivities of many species associated with dead wood remain unknown, making it difficult to develop conservation plans for managed forests. The purpose of this research, conducted on the upper coastal plain of South Carolina, was to better understand the relationships between dead wood and arthropods in the southeastern United States. In a comparison of forest types, more beetle species emerged from logs collected in upland pine-dominated stands than in bottomland hardwood forests. This difference was most pronounced for Quercus nigra L., a species of tree uncommon in upland forests. In a comparison of wood postures, more beetle species emerged from logs than from snags, but a number of species appear to be dependent on snags including several canopy specialists. In a study of saproxylic beetle succession, species richness peaked within the first year of death and declined steadily thereafter. However, a number of species appear to be dependent on highly decayed logs, underscoring the importance of protecting wood at all stages of decay. In a study comparing litter-dwelling arthropod abundance at different distances from dead wood, arthropods were more abundant near dead wood than away from it. In another study, grounddwelling arthropods and saproxylic beetles were little affected by large-scale manipulations of dead wood in upland pine-dominated forests, possibly due to the suitability of the forests surrounding the plots.

  18. Equal temperature-size responses of the sexes are widespread within arthropod species

    DEFF Research Database (Denmark)

    Hirst, Andrew G.; Horne, Curtis; Atkinson, David

    2015-01-01

    Sexual size dimorphism (SSD) is often affected by environmental conditions, but the effect of temperature on SSD in ectotherms still requires rigorous investigation. We compared the plastic responses of size-at-maturity to temperature between males and females within 85 diverse arthropod species,...

  19. Arthropod-borne flaviviruses and RNA interference : seeking new approaches for antiviral therapy

    NARCIS (Netherlands)

    Diosa-Toro, Mayra; Urcuqui-Inchima, Silvio; Smit, Jolanda M

    2013-01-01

    Flaviviruses are the most prevalent arthropod-borne viruses worldwide, and nearly half of the 70 Flavivirus members identified are human pathogens. Despite the huge clinical impact of flaviviruses, there is no specific human antiviral therapy available to treat infection with any of the flaviviruses

  20. The Hunsrück biota: A unique window into the ecology of Lower Devonian arthropods.

    Science.gov (United States)

    Rust, Jes; Bergmann, Alexandra; Bartels, Christoph; Schoenemann, Brigitte; Sedlmeier, Stephanie; Kühl, Gabriele

    2016-03-01

    The approximately 400-million-year old Hunsrück biota provides a unique window into Devonian marine life. Fossil evidence suggests that this biota was dominated by echinoderms and various classes of arthropods, including Trilobita, stem lineage representatives of Euarthropoda, Chelicerata and Eucrustacea, as well as several crown group Chelicerata and Eucrustacea. The Hunsrück biota's exceptional preservation allows detailed reconstructions and description of key-aspects of its fauna's functional morphologies thereby revealing modes of locomotion, sensory perception, and feeding strategies. Morphological and stratigraphic data are used for a critical interpretation of the likely habitats, mode of life and nutritional characteristics of this diverse fauna. Potential predators include pycnogonids and other chelicerates, as well as the now extinct stem arthropods Schinderhannes bartelsi, Cambronatus brasseli and Wingertshellicus backesi. Mainly the deposit feeding Trilobita, Marrellomorpha and Megacheira, such as Bundenbachiellus giganteus, represents scavengers. Possibly, opportunistic scavenging was also performed by the afore-mentioned predators. Most of the studied arthropods appear to have been adapted to living in relatively well-illuminated conditions within the photic zone. Fossil evidence for associations amongst arthropods and other classes of metazoans is reported. These associations provide evidence of likely community structures.

  1. Natural products from forest resources for use as arthropod and fungal biocides.

    Science.gov (United States)

    Natural products from Pacific Northwest forest resources can offer alternatives to the use of synthetic pesticides in the control of both arthropods of public health concern and forest fungal pathogens. Tree heartwood extracts with high toxicity (low LC50) in preliminary brine shrimp bioassays were...

  2. Pheromone-mediated aggregation in nonsocial arthropods : An evolutionary ecological perspective

    NARCIS (Netherlands)

    Wertheim, B; van Baalen, EJA; Dicke, M; Vet, LEM

    2005-01-01

    Although the use of aggregation pheromones has been reported for hundreds of nonsocial arthropod species, the evolutionary ecological aspects of this behavior have received little attention. Despite the elaborate literature on mechanisms. robust data on costs and benefits of aggregation pheromones a

  3. Pheromone-mediated aggregation in nonsocial arthropods: an evolutionary ecological perspective

    NARCIS (Netherlands)

    Wertheim, B.; Baalen, van E.J.A.; Dicke, M.; Vet, L.E.M.

    2005-01-01

    Although the use of aggregation pheromones has been reported for hundreds of nonsocial arthropod species, the evolutionary ecological aspects of this behavior have received little attention. Despite the elaborate literature on mechanisms, robust data on costs and benefits of aggregation pheromones a

  4. Arthropods, plants, and transmission lines in Arizona: secondary succession in a Sonoran Desert habitat

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, C.D.; Ditsworth, T.M.; Beley, J.R.

    1981-09-01

    Overall arthropod densities were low at this site, but the arthropod densities on the disturbed areas appeared to be enhanced after several years. No taxa were found to be statistically different in density between control and disturbed plots. Diversity decreased on the disturbed area after construction. Arthropod community similarity (C) was lower after construction, but C values appear to be related to presence or absence of annual herbs and grasses and not to total cover. Except for globe mallow, there were no pioneer plant species on the experimental plot. Effects of powerline construction on the experimental plant community were a brief reduction in total cover and a slight increase in cover of herbs and annual grasses. The 1976 and 1977 samples exhibit comparable cover values of these plants on both experimental and control plots. The dominant arthropod taxa on the experimental area (especially Thysanoptera, Cicadellidae, Coccinellidae, and Melyridae) appear to be responding numerically to the annual herbs and grasses which are becoming established on the plot.

  5. Grazed vegetation mosaics do not maximize arthropod diversity : Evidence from salt marshes

    NARCIS (Netherlands)

    van Klink, Roel; Rickert, Corinna; Vermeulen, Rikjan; Vorst, Oscar; WallisDeVries, Michiel F.; Bakker, Jan P.

    2013-01-01

    Light to moderate grazing in grasslands can create vegetation mosaics of short grazed vegetation and tall ungrazed vegetation. These mosaics have been proposed to maximize plant and animal species richness, yet experimental evidence, especially regarding arthropods is scarce. This study compares abu

  6. Grazed vegetation mosaics do not maximize arthropod diversity: Evidence from salt marshes

    NARCIS (Netherlands)

    Klink, van R.; Rickert, C.; Vermeulen, R.; Vorst, O.; Wallis de Vries, M.F.; Bakker, J.P.

    2013-01-01

    Light to moderate grazing in grasslands can create vegetation mosaics of short grazed vegetation and tall ungrazed vegetation. These mosaics have been proposed to maximize plant and animal species richness, yet experimental evidence, especially regarding arthropods is scarce. This study compares abu

  7. Teaching Students about Biodiversity by Studying the Correlation between Plants & Arthropods

    Science.gov (United States)

    Richardson, Matthew L.; Hari, Janice

    2008-01-01

    On Earth there is a huge diversity of arthropods, many of which are highly adaptive and able to exploit virtually every terrestrial habitat. Because of their prevalence even in urban environments, they make an excellent model system for any life science class. Since plants also exploit virtually every terrestrial habitat, studying the relationship…

  8. Selectivity lists of pesticides to beneficial arthropods for IPM programs in carrot--first results.

    OpenAIRE

    Hautier, L.; Jansen, J.-P.; Mabon, N.; Schiffers, Bruno

    2005-01-01

    In order to improve IPM programs in carrot, 7 fungicides, 12 herbicides and 9 insecticides commonly used in Belgium were tested for their toxicity towards five beneficial arthropods representative of most important natural enemies encountered in carrot: parasitic wasps- Aphidius rhopalosiphi (De Stefani-Perez) (Hym., Aphidiidae), ladybirds - Adalia bipunctata (L.) (Col., Coccinellidae), hoverfly - Episyrphus balteatus (Dipt., Syrphidae), rove beetle - Aleochara bilineata (Col., Staphyllinida...

  9. Evolutionary genomics place the origin of Wolbachia in nematodes, not arthropods

    Science.gov (United States)

    Wolbachia, the most widely studied endosymbiont in arthropods, is a target for biological control of mosquito-borne diseases (malaria and dengue virus), and antibiotic elimination of infectious filarial nematodes. We sequenced and analyzed the genome of a new strain (wPpe) in the plant-parasitic nem...

  10. Selected examples of dispersal of arthropods associated with agricultural crop and animal production

    Science.gov (United States)

    Henneberry, T. J.

    1979-01-01

    The economic importance of arthropods in agricultural production systems and the possibilities of using dispersal behavior to develop and manipulate control are examined. Examples of long and short distance dispersal of economic insect pests and beneficial species from cool season host reservoirs and overwintering sites are presented. Significant dispersal of these species often occurring during crop and animal production is discussed.

  11. Differential Rickettsial Transcription in Bloodfeeding and Non-Bloodfeeding Arthropod Hosts

    Science.gov (United States)

    Verhoeve, Victoria I.; Jirakanwisal, Krit; Utsuki, Tadanobu; Macaluso, Kevin R.

    2016-01-01

    Crucial factors influencing the epidemiology of Rickettsia felis rickettsiosis include pathogenesis and transmission. Detection of R. felis DNA in a number of arthropod species has been reported, with characterized isolates, R. felis strain LSU and strain LSU-Lb, generated from the cat flea, Ctenocephalides felis, and the non-hematophagous booklouse, Liposcelis bostrychophila, respectively. While it is realized that strain influence on host biology varies, the rickettsial response to these distinct host environments remained undefined. To identify a panel of potential rickettsial transmission determinants in the cat flea, the transcriptional profile for these two strains of R. felis were compared in their arthropod hosts using RNAseq. Rickettsial genes with increased transcription in the flea as compared to the booklouse were identified. Genes previously associated with bacterial virulence including LPS biosynthesis, Type IV secretion system, ABC transporters, and a toxin-antitoxin system were selected for further study. Transcription of putative virulence-associated genes was determined in a flea infection bioassay for both strains of R. felis. A host-dependent transcriptional profile during bloodfeeding, specifically, an increased expression of selected transcripts in newly infected cat fleas and flea feces was detected when compared to arthropod cell culture and incubation in vertebrate blood. Together, these studies have identified novel, host-dependent rickettsial factors that likely contribute to successful horizontal transmission by bloodfeeding arthropods. PMID:27662479

  12. THE ROLE OF DEAD WOOD IN MAINTAINING ARTHROPOD DIVERSITY ON THE FOREST FLOOR.

    Energy Technology Data Exchange (ETDEWEB)

    Hanula, James L.; Horn, Scott; Wade, Dale D.

    2006-08-01

    Abstract—Dead wood is a major component of forests and contributes to overall diversity, primarily by supporting insects that feed directly on or in it. Further, a variety of organisms benefit by feeding on those insects. What is not well known is how or whether dead wood influences the composition of the arthropod community that is not solely dependent on it as a food resource, or whether woody debris influences prey available to generalist predators. One group likely to be affected by dead wood is ground-dwelling arthropods. We studied the effect of adding large dead wood to unburned and frequently burned pine stands to determine if dead wood was used more when the litter and understory plant community are removed. We also studied the effect of annual removal of dead wood from large (10-ha) plots over a 5-year period on ground-dwelling arthropods. In related studies, we examined the relationships among an endangered woodpecker that forages for prey on live trees, its prey, and dead wood in the forest. The results of these and other studies show that dead wood can influence the abundance and diversity of the ground-dwelling arthropod community and of prey available to generalist predators not foraging directly on dead trees.

  13. Influence of buffalograss management practices on Western chinch bug and its beneficial arthropods.

    Science.gov (United States)

    Carstens, Jeffrey; Heng-Moss, Tiffany; Baxendale, Frederick; Gaussoin, Roch; Frank, Kevin; Young, Linda

    2007-02-01

    A 2-yr study was conducted to document the influence of selected buffalograss, Buchloë dactyloides (Nuttall) Engelmann, management practices (three mowing heights and five nitrogen levels) on the seasonal abundance of the western chinch bug, Blissus occiduus Barber (Heteroptera: Lygaeidae), and its beneficial arthropods. Vacuum, pitfall, and sticky traps samples were collected every 14 d from the middle of May through October from western chinch bug-resistant ('Prestige') and -susceptible ('378') buffalograss management plots. In total, 27,374 and 108,908 western chinch bugs were collected in vacuum and pitfall traps, respectively. More than 78% of all western chinch bugs were collected from the highly susceptible buffalograss 378. Significantly more bigeyed bugs (Geocoridae: Geocoris spp.) were collected from the 378 buffalograsss management plots than the Prestige plots. In contrast, buffalograss cultivar had little influence on the abundance of other beneficial arthropods collected. Statistically, western chinch bugs were least abundant at the lowest mowing height (2.5 cm) and increased in abundance with increasing fertility. Numerically, however, differences among management levels on western chinch bug abundance were minimal. Numerous beneficial arthropods were collected from buffalograss management plots, including spiders, predatory ants, ground beetles (Carabidae), rove beetles (Staphylinidae), bigeyed bugs, and several species of hymenopterous parasitoids. In general, beneficial arthropods were essentially unaffected by either mowing height or nitrogen level. Scelionid wasps represented 66.3% of the total parasitoids collected. The total number of scelionid wasps collected among the three mowing heights and five nitrogen levels were approximately equal. PMID:17370821

  14. The population genetic structure of vectors and our understanding of disease epidemiology

    Directory of Open Access Journals (Sweden)

    McCoy K.D.

    2008-09-01

    Full Text Available Understanding and predicting disease epidemiology relies on clear knowledge about the basic biology of the organisms involved. Despite the key role that arthropod vectors play in disease dynamics and detailed mechanistic work on the vectorpathogen interface, little information is often available about how these populations function under natural conditions. Population genetic studies can help fill this void by providing information about the taxonomic status of species, the spatial limits of populations, and the nature of gene flow among populations. Here, I briefly review different types of population genetic structure and some recent examples of where this information has provided key elements for understanding pathogen transmission in tick-borne systems.

  15. GAP Land Cover - Vector

    Data.gov (United States)

    Minnesota Department of Natural Resources — This vector dataset is a detailed (1-acre minimum), hierarchically organized vegetation cover map produced by computer classification of combined two-season pairs...

  16. Noncausal Bayesian Vector Autoregression

    DEFF Research Database (Denmark)

    Lanne, Markku; Luoto, Jani

    We propose a Bayesian inferential procedure for the noncausal vector autoregressive (VAR) model that is capable of capturing nonlinearities and incorporating effects of missing variables. In particular, we devise a fast and reliable posterior simulator that yields the predictive distribution...

  17. Understanding Vector Fields.

    Science.gov (United States)

    Curjel, C. R.

    1990-01-01

    Presented are activities that help students understand the idea of a vector field. Included are definitions, flow lines, tangential and normal components along curves, flux and work, field conservation, and differential equations. (KR)

  18. Tagged Vector Contour (TVC)

    Data.gov (United States)

    Kansas Data Access and Support Center — The Kansas Tagged Vector Contour (TVC) dataset consists of digitized contours from the 7.5 minute topographic quadrangle maps. Coverage for the state is incomplete....

  19. The colonization of land by animals: molecular phylogeny and divergence times among arthropods

    Directory of Open Access Journals (Sweden)

    Lyons-Weiler Maureen

    2004-01-01

    Full Text Available Abstract Background The earliest fossil evidence of terrestrial animal activity is from the Ordovician, ~450 million years ago (Ma. However, there are earlier animal fossils, and most molecular clocks suggest a deep origin of animal phyla in the Precambrian, leaving open the possibility that animals colonized land much earlier than the Ordovician. To further investigate the time of colonization of land by animals, we sequenced two nuclear genes, glyceraldehyde-3-phosphate dehydrogenase and enolase, in representative arthropods and conducted phylogenetic and molecular clock analyses of those and other available DNA and protein sequence data. To assess the robustness of animal molecular clocks, we estimated the deuterostome-arthropod divergence using the arthropod fossil record for calibration and tunicate instead of vertebrate sequences to represent Deuterostomia. Nine nuclear and 15 mitochondrial genes were used in phylogenetic analyses and 61 genes were used in molecular clock analyses. Results Significant support was found for the unconventional pairing of myriapods (millipedes and centipedes with chelicerates (spiders, scorpions, horseshoe crabs, etc. using nuclear and mitochondrial genes. Our estimated time for the divergence of millipedes (Diplopoda and centipedes (Chilopoda was 442 ± 50 Ma, and the divergence of insects and crustaceans was estimated as 666 ± 58 Ma. Our results also agree with previous studies suggesting a deep divergence (~1100 – 900 Ma for arthropods and deuterostomes, considerably predating the Cambrian Explosion seen in the animal fossil record. Conclusions The consistent support for a close relationship between myriapods and chelicerates, using mitochondrial and nuclear genes and different methods of analysis, suggests that this unexpected result is not an artefact of analysis. We propose the name Myriochelata for this group of animals, which includes many that immobilize prey with venom. Our molecular clock

  20. Implicit Real Vector Automata

    OpenAIRE

    Jean-François Degbomont; Julien Brusten; Bernard Boigelot

    2010-01-01

    This paper addresses the symbolic representation of non-convex real polyhedra, i.e., sets of real vectors satisfying arbitrary Boolean combinations of linear constraints. We develop an original data structure for representing such sets, based on an implicit and concise encoding of a known structure, the Real Vector Automaton. The resulting formalism provides a canonical representation of polyhedra, is closed under Boolean operators, and admits an efficient decision procedure for testing the ...

  1. Vector Lattice Vortex Solitons

    Institute of Scientific and Technical Information of China (English)

    WANG Jian-Dong; YE Fang-Wei; DONG Liang-Wei; LI Yong-Ping

    2005-01-01

    @@ Two-dimensional vector vortex solitons in harmonic optical lattices are investigated. The stability properties of such solitons are closely connected to the lattice depth Vo. For small Vo, vector vortex solitons with the total zero-angular momentum are more stable than those with the total nonzero-angular momentum, while for large Vo, this case is inversed. If Vo is large enough, both the types of such solitons are stable.

  2. Support vector machines applications

    CERN Document Server

    Guo, Guodong

    2014-01-01

    Support vector machines (SVM) have both a solid mathematical background and good performance in practical applications. This book focuses on the recent advances and applications of the SVM in different areas, such as image processing, medical practice, computer vision, pattern recognition, machine learning, applied statistics, business intelligence, and artificial intelligence. The aim of this book is to create a comprehensive source on support vector machine applications, especially some recent advances.

  3. Vector financial rogue waves

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Zhenya, E-mail: zyyan@mmrc.iss.ac.cn [Key Laboratory of Mathematics Mechanization, Institute of Systems Science, AMSS, Chinese Academy of Sciences, Beijing 100190 (China)

    2011-11-21

    The coupled nonlinear volatility and option pricing model presented recently by Ivancevic is investigated, which generates a leverage effect, i.e., stock volatility is (negatively) correlated to stock returns, and can be regarded as a coupled nonlinear wave alternative of the Black–Scholes option pricing model. In this Letter, we analytically propose vector financial rogue waves of the coupled nonlinear volatility and option pricing model without an embedded w-learning. Moreover, we exhibit their dynamical behaviors for chosen different parameters. The vector financial rogue wave (rogon) solutions may be used to describe the possible physical mechanisms for the rogue wave phenomena and to further excite the possibility of relative researches and potential applications of vector rogue waves in the financial markets and other related fields. -- Highlights: ► We investigate the coupled nonlinear volatility and option pricing model. ► We analytically present vector financial rogue waves. ► The vector financial rogue waves may be used to describe the extreme events in financial markets. ► This results may excite the relative researches and potential applications of vector rogue waves.

  4. Vector financial rogue waves

    International Nuclear Information System (INIS)

    The coupled nonlinear volatility and option pricing model presented recently by Ivancevic is investigated, which generates a leverage effect, i.e., stock volatility is (negatively) correlated to stock returns, and can be regarded as a coupled nonlinear wave alternative of the Black–Scholes option pricing model. In this Letter, we analytically propose vector financial rogue waves of the coupled nonlinear volatility and option pricing model without an embedded w-learning. Moreover, we exhibit their dynamical behaviors for chosen different parameters. The vector financial rogue wave (rogon) solutions may be used to describe the possible physical mechanisms for the rogue wave phenomena and to further excite the possibility of relative researches and potential applications of vector rogue waves in the financial markets and other related fields. -- Highlights: ► We investigate the coupled nonlinear volatility and option pricing model. ► We analytically present vector financial rogue waves. ► The vector financial rogue waves may be used to describe the extreme events in financial markets. ► This results may excite the relative researches and potential applications of vector rogue waves.

  5. The Vector Curvaton

    CERN Document Server

    Navarro, Andres A

    2013-01-01

    We analyze a massive vector field with a non-canonical kinetic term in the action, minimally coupled to gravity, where the mass and kinetic function of the vector field vary as functions of time during inflation. The vector field is introduced following the same idea of a scalar curvaton, which must not affect the inflationary dynamics since its energy density during inflation is negligible compared to the total energy density in the Universe. Using this hypothesis, the vector curvaton will be solely responsible for generating the primordial curvature perturbation \\zeta. We have found that the spectra of the vector field perturbations are scale-invariant in superhorizon scales due to the suitable choice of the time dependence of the kinetic function and the effective mass during inflation. The preferred direction, generated by the vector field, makes the spectrum of \\zeta depend on the wavevector, i.e. there exists statistical anisotropy in \\zeta. This is discussed principally in the case where the mass of th...

  6. Employing citizen science to study defoliation impacts on arthropod communities on tamarisk

    Science.gov (United States)

    Kruse, Audrey L.

    The invasive tamarisk tree is widespread across the southwestern landscape of the United States and has been dominant in regulated river reaches, outcompeting native vegetation and impacting trophic webs in riparian ecosystems. The changes in riparian habitat and recreation opportunities along southwestern rivers, like the San Juan River in Utah, led to the implementation of a biocontrol program in the form of the tamarisk leaf beetle (Diorhabda spp.). It is unknown what the long term effects on riparian ecosystems are as a result of the beetles' defoliation of tamarisk each summer. This study sought to identify the current arthropod community composition and abundance over one growing season on the San Juan River between Bluff and Mexican Hat, UT and second, to involve the public in this research through a citizen science component. I found that non-native insects, including the tamarisk leaf beetle, dominated the arboreal arthropod communities within the tamarisk and there are relatively few native arthropods residing in tamarisk throughout the summer season. Foliation levels (the quantity of leaves in the canopy of tamarisk) were inconclusive predictors of arthropod abundances but varied by species and by feeding guild. This may indicate that the defoliation of the tamarisk is not necessarily negatively impacting trophic interactions in tamarisk. I incorporated youth participants on educational river rafting trips to assist in data collection of arthropods from tamarisk trees as a way to educate and bring attention to the issue of invasive species in the Southwest. After completing my own citizen science project and after doing a literature review of other, similar citizen science projects, I found that striving for both rigorous scientific data and quality educational programming is challenging for a small scale project that does not target broad spatial, geographic, or temporal data. Citizen science project developers should clearly identify their objectives

  7. Habitat connectivity shapes urban arthropod communities: the key role of green roofs.

    Science.gov (United States)

    Braaker, S; Ghazoul, J; Obrist, M K; Moretti, M

    2014-04-01

    The installation of green roofs, defined here as rooftops with a shallow soil cover and extensive vegetation, has been proposed as a possible measure to mitigate the loss of green space caused by the steady growth of cities. However, the effectiveness of green roofs in supporting arthropod communities, and the extent to which they facilitate connectivity of these communities within the urban environment is currently largely unknown. We investigated the variation of species community composition (beta diversity) of four arthropod groups with contrasting mobility (Carabidae, Araneae, Curculionidae, and Apidae) on 40 green roofs and 40 extensively managed green sites on the ground in the city of Zurich, Switzerland. With redundancy analysis and variation partitioning, we (1) disentangled the relative importance of local environmental conditions, the surrounding land cover composition, and habitat connectivity on species community composition, (2) searched for specific spatial scales of habitat connectivity for the different arthropod groups, and (3) discussed the ecological and functional value of green roofs in cities. Our study revealed that on green roofs community composition of high-mobility arthropod groups (bees and weevils) were mainly shaped by habitat connectivity, while low-mobility arthropod groups (carabids and spiders) were more influenced by local environmental conditions. A similar but less pronounced pattern was found for ground communities. The high importance of habitat connectivity in shaping high-mobility species community composition indicates that these green roof communities are substantially connected by the frequent exchange of individuals among surrounding green roofs. On the other hand, low-mobility species communities on green roofs are more likely connected to ground sites than to other green roofs. The integration of green roofs in urban spatial planning strategies has great potential to enable higher connectivity among green spaces, so

  8. Habitat connectivity shapes urban arthropod communities: the key role of green roofs.

    Science.gov (United States)

    Braaker, S; Ghazoul, J; Obrist, M K; Moretti, M

    2014-04-01

    The installation of green roofs, defined here as rooftops with a shallow soil cover and extensive vegetation, has been proposed as a possible measure to mitigate the loss of green space caused by the steady growth of cities. However, the effectiveness of green roofs in supporting arthropod communities, and the extent to which they facilitate connectivity of these communities within the urban environment is currently largely unknown. We investigated the variation of species community composition (beta diversity) of four arthropod groups with contrasting mobility (Carabidae, Araneae, Curculionidae, and Apidae) on 40 green roofs and 40 extensively managed green sites on the ground in the city of Zurich, Switzerland. With redundancy analysis and variation partitioning, we (1) disentangled the relative importance of local environmental conditions, the surrounding land cover composition, and habitat connectivity on species community composition, (2) searched for specific spatial scales of habitat connectivity for the different arthropod groups, and (3) discussed the ecological and functional value of green roofs in cities. Our study revealed that on green roofs community composition of high-mobility arthropod groups (bees and weevils) were mainly shaped by habitat connectivity, while low-mobility arthropod groups (carabids and spiders) were more influenced by local environmental conditions. A similar but less pronounced pattern was found for ground communities. The high importance of habitat connectivity in shaping high-mobility species community composition indicates that these green roof communities are substantially connected by the frequent exchange of individuals among surrounding green roofs. On the other hand, low-mobility species communities on green roofs are more likely connected to ground sites than to other green roofs. The integration of green roofs in urban spatial planning strategies has great potential to enable higher connectivity among green spaces, so

  9. Impact of Location, Cropping History, Tillage, and Chlorpyrifos on Soil Arthropods in Peanut.

    Science.gov (United States)

    Cardoza, Yasmin J; Drake, Wendy L; Jordan, David L; Schroeder-Moreno, Michelle S; Arellano, Consuelo; Brandenburg, Rick L

    2015-08-01

    Demand for agricultural production systems that are both economically viable and environmentally conscious continues to increase. In recent years, reduced tillage systems, and grass and pasture rotations have been investigated to help maintain or improve soil quality, increase crop yield, and decrease labor requirements for production. However, documentation of the effects of reduced tillage, fescue rotation systems as well as other management practices, including pesticides, on pest damage and soil arthropod activity in peanut production for the Mid-Atlantic US region is still limited. Therefore, this project was implemented to assess impacts of fescue-based rotation systems on pests and other soil organisms when compared with cash crop rotation systems over four locations in eastern North Carolina. In addition, the effects of tillage (strip vs. conventional) and soil chlorpyrifos application on pod damage and soil-dwelling organisms were also evaluated. Soil arthropod populations were assessed by deploying pitfall traps containing 50% ethanol in each of the sampled plots. Results from the present study provide evidence that location significantly impacts pest damage and soil arthropod diversity in peanut fields. Cropping history also influenced arthropod diversity, with higher diversity in fescue compared with cash crop fields. Corn rootworm damage to pods was higher at one of our locations (Rocky Mount) compared with all others. Cropping history (fescue vs. cash crop) did not have an effect on rootworm damage, but increased numbers of hymenopterans, acarina, heteropterans, and collembolans in fescue compared with cash crop fields. Interestingly, there was an overall tendency for higher number of soil arthropods in traps placed in chlorpyrifos-treated plots compared with nontreated controls. PMID:26314040

  10. Arthropod prey for riparian associated birds in headwater forests of the Oregon Coast Range

    Science.gov (United States)

    Hagar, Joan C.; Li, Judith; Sobota, Janel; Jenkins, Stephanie

    2012-01-01

    Headwater riparian areas occupy a large proportion of the land base in Pacific Northwest forests, and thus are ecologically and economically important. Although a primary goal of management along small headwater streams is the protection of aquatic resources, streamside habitat also is important for many terrestrial wildlife species. However, mechanisms underlying the riparian associations of some terrestrial species have not been well studied, particularly for headwater drainages. We investigated the diets of and food availability for four bird species associated with riparian habitats in montane coastal forests of western Oregon, USA. We examined variation in the availability of arthropod prey as a function of distance from stream. Specifically, we tested the hypotheses that (1) emergent aquatic insects were a food source for insectivorous birds in headwater riparian areas, and (2) the abundances of aquatic and terrestrial arthropod prey did not differ between streamside and upland areas during the bird breeding season. We found that although adult aquatic insects were available for consumption throughout the study period, they represented a relatively small proportion of available prey abundance and biomass and were present in only 1% of the diet samples from only one of the four riparian-associated bird species. Nonetheless, arthropod prey, comprised primarily of insects of terrestrial origin, was more abundant in streamside than upland samples. We conclude that food resources for birds in headwater riparian areas are primarily associated with terrestrial vegetation, and that bird distributions along the gradient from streamside to upland may be related to variation in arthropod prey availability. Because distinct vegetation may distinguish riparian from upland habitats for riparian-associated birds and their terrestrial arthropod prey, we suggest that understory communities be considered when defining management zones for riparian habitat.

  11. From embryo to adult--beyond the conventional periodization of arthropod development.

    Science.gov (United States)

    Minelli, Alessandro; Brena, Carlo; Deflorian, Gianluca; Maruzzo, Diego; Fusco, Giuseppe

    2006-01-01

    The traditional framework for the description of arthropod development takes the molt-to-molt interval as the fundamental unit of periodization, which is similar to the morphological picture of the main body axis as a series of segments. Developmental time is described as the subdivision into a few major stages of one or more instars each, which is similar to the subdivision of the main body axis into regions of one to many segments each. Parallel to recent criticisms to the segment as the fundamental building block of arthropod anatomy, we argue that, while a firm subdivision of development in stages is useful for describing arthropod ontogeny, this is limiting as a starting point for studying its evolution. Evolutionary change affects the association between different developmental processes, some of which are continuous in time whereas others are linked to the molting cycle. Events occurring but once in life (hatching; first achieving sexual maturity) are traditionally used to establish boundaries between major units of arthropod developmental time, but these boundaries are quite labile. The presence of embryonic molts, the 'gray zone' of development accompanying hatching (with the frequent delivery of an immature whose qualification as 'free-embryo' or ordinary postembryonic stage is arbitrary), and the frequent decoupling of growth and molting suggest a different view. Beyond the simple comparison of developmental schedules in terms of heterochrony, the flexible canvas we suggest for the analysis of arthropod development opens new vistas into its evolution. Examples are provided as to the origin of holometaboly and hypermetaboly within the insects. PMID:16670874

  12. Mineral cycling in soil and litter arthropod food chains. Progress report, November 1, 1981-January 31, 1983

    International Nuclear Information System (INIS)

    Progress is reported for research projects on nutrient dynamics during terrestrial decomposition, as influenced by soil arthropods. Radioactive tracers are used as analogs of nutrients, to measure material movement along food chains and dynamics of processes during decomposition. Forest floor systems from which arthropods were excluded, or in which microfloral activity was depressed, trapped incoming nutrients from canopy throughfall at different rates. Faunal stimulation of microfloral activities could not be demonstrated, but drought conditions disturbed the experiment. Turnover measurements for radionuclides in collembolans are also reported, and compared with information on mites and other arthropods

  13. Extended Mixed Vector Equilibrium Problems

    Directory of Open Access Journals (Sweden)

    Mijanur Rahaman

    2014-01-01

    Full Text Available We study extended mixed vector equilibrium problems, namely, extended weak mixed vector equilibrium problem and extended strong mixed vector equilibrium problem in Hausdorff topological vector spaces. Using generalized KKM-Fan theorem (Ben-El-Mechaiekh et al.; 2005, some existence results for both problems are proved in noncompact domain.

  14. APPLICATION OF BIOTECHNOLOGY TO THE STUDY OF FILARIAL PARASITES AND THEIR VECTORS

    Directory of Open Access Journals (Sweden)

    A. C. Vickery

    2012-09-01

    Full Text Available Over 200 species of filarial parasites have been described, although the life cycle and nature of their obligate intermediate arthropod vectors have been identified for only about a quarter of them. Traditional methods of studying phylogenetic relationships between closely related parasite species have utilized morphologic, biochemical and biologic characteristics, usually of the microfilarial stage. Identification of competent vectors from among complexes of sibling species, has employed similar techniques, despite the fact that differences between geographical isolates may reflect environmental rather than genetically controlled factors. Studies of the prevalence and transmission of animal, human and zoonotic filarids, so important for vector identification and control, has lead to the examination of filarial parasites at the genetic level. Genomic DNA libraries are being constructed and screened for clones which are species specific. From this work, DNA probes which can accurately enumerate larval stages in vector squash preparations, and monoclonal antibodies specific for defined filarial antigens, are being prepared. The nucleotide sequences of rRNA are also being defined. The application of these technologies to the study of filarial parasites and their vectors, promises to not only allow the construction of accurate phylogenetic trees, but also to provide the data necessary for the identification and control of the vectors of filarial pathogens of animals and man.

  15. Modeling vector-borne disease risk in migratory animals under climate change.

    Science.gov (United States)

    Hall, Richard J; Brown, Leone M; Altizer, Sonia

    2016-08-01

    Recent theory suggests that animals that migrate to breed at higher latitudes may benefit from reduced pressure from natural enemies, including pathogens ("migratory escape"), and that migration itself weeds out infected individuals and lowers infection prevalence ("migratory culling"). The distribution and activity period of arthropod disease vectors in temperate regions is expected to respond rapidly to climate change, which could reduce the potential for migratory escape. However, climate change could have the opposite effect of reducing transmission if differential responses in the phenology and distribution of migrants and disease vectors reduce their overlap in space and time. Here we outline a simple modeling framework for exploring the influence of climate change on vector-borne disease dynamics in a migratory host. We investigate two scenarios under which pathogen transmission dynamics might be mediated by climate change: (1) vectors respond more rapidly than migrants to advancing phenology at temperate breeding sites, causing peak susceptible host density and vector emergence to diverge ("migratory mismatch") and (2) reduced migratory propensity allows increased nonbreeding survival of infected hosts and larger breeding-site epidemics (loss of migratory culling, here referred to as "sedentary amplification"). Our results highlight the need for continued surveillance of climate-induced changes to migratory behavior and vector activity to predict pathogen prevalence and its impacts on migratory animals. PMID:27252225

  16. Modeling vector-borne disease risk in migratory animals under climate change.

    Science.gov (United States)

    Hall, Richard J; Brown, Leone M; Altizer, Sonia

    2016-08-01

    Recent theory suggests that animals that migrate to breed at higher latitudes may benefit from reduced pressure from natural enemies, including pathogens ("migratory escape"), and that migration itself weeds out infected individuals and lowers infection prevalence ("migratory culling"). The distribution and activity period of arthropod disease vectors in temperate regions is expected to respond rapidly to climate change, which could reduce the potential for migratory escape. However, climate change could have the opposite effect of reducing transmission if differential responses in the phenology and distribution of migrants and disease vectors reduce their overlap in space and time. Here we outline a simple modeling framework for exploring the influence of climate change on vector-borne disease dynamics in a migratory host. We investigate two scenarios under which pathogen transmission dynamics might be mediated by climate change: (1) vectors respond more rapidly than migrants to advancing phenology at temperate breeding sites, causing peak susceptible host density and vector emergence to diverge ("migratory mismatch") and (2) reduced migratory propensity allows increased nonbreeding survival of infected hosts and larger breeding-site epidemics (loss of migratory culling, here referred to as "sedentary amplification"). Our results highlight the need for continued surveillance of climate-induced changes to migratory behavior and vector activity to predict pathogen prevalence and its impacts on migratory animals.

  17. The effects of the identity of shrub species on the distribution and diversity of ground arthropods in a sandy desert ecosystem of northwestern China

    Institute of Scientific and Technical Information of China (English)

    JiLiang Liu; WenZhi Zhao; FengRui Li

    2014-01-01

    Shrub is an important factor on structuring ground arthropod communities in desert ecosystems. In this study, in order to determine how shrubs and their species influence ground arthropod distribution patterns in a sandy desert scrubland dominated by two different shrub species, Calligonum mongolicum and Nitraria sphaerocarpa, the ground arthropods were sampled with pitfall traps during spring, summer and autumn. At the community level, total arthropod abundance was shown to be significantly higher under shrubs than in intershrub bare areas in spring;similar patterns occurred in terms of the richness of arthropod groups in the spring and over three seasons, suggesting season-specific shrub presence effects on arthropod activity. In addition, more arthropods were found under N. sphaerocarpa shrubs than under C. mongolicum shrubs in autumn, suggesting season-specific effects of shrub species of arthropod activity, whereas more arthropods taxa were captured under C. mongolicum than N. sphaerocarpa. At the trophic group level, the abundances of predator and herbivore arthropods were significantly greater under shrubs than in intershrub bare habitats, whereas herbivore arthropods were more abundant under N. sphaerocarpa than C. mongolicum, and an opposite rule was detected for predator arthropods. At the family level, the mean abundances of Carabidae, Curculionidae, Gnaphosidae and Lycosidae were significantly higher in the shrub microhabitats than in the intershrub bare habitat, there was no significant difference between habitats on the mean abundances of Formicidae and Tenebrionidae. The study results suggested that shrub presence and shrub species variation are important determinants of ground arthropod assemblages in this desert ecosystem, but the responses of ar-thropods differed among trophic and taxonomic groups.

  18. SEM characterization of anatomical variation in chitin organization in insect and arthropod cuticles.

    Science.gov (United States)

    Chandran, Rakkiyappan; Williams, Lee; Hung, Albert; Nowlin, Kyle; LaJeunesse, Dennis

    2016-03-01

    The cuticles of insects and arthropods have some of the most diverse material properties observed in nature, so much so that it is difficult to imagine that all cutciles are primarily composed of the same two materials: a fibrous chitin network and a matrix composed of cuticle proteins. Various factors contribute to the mechanical and optical properties of an insect or arthropod cuticle including the thickness and composition. In this paper, we also identified another factor that may contribute to the optical, surface, and mechanical properties of a cuticle, i.e. the organization of chitin nanofibers and chitin fiber bundles. Self-assembled chitin nanofibers serve as the foundation for all higher order chitin structures in the cuticles of insects and other arthropods via interactions with structural cuticle proteins. Using a technique that enables the characterization of chitin organization in the cuticle of intact insects and arthropod exoskeletons, we demonstrate a structure/function correlation of chitin organization with larger scale anatomical structures. The chitin scaffolds in cuticles display an extraordinarily diverse set of morphologies that may reflect specific mechanical or physical properties. After removal of the proteinaceous and mineral matrix of a cuticle, we observe using SEM diverse nanoscale and micro scale organization of in-situ chitin in the wing, head, eye, leg, and dorsal and ventral thoracic regions of the periodical cicada Magicicada septendecim and in other insects and arthropods. The organization of chitin also appears to have a significant role in the organization of nanoscale surface structures. While microscale bristles and hairs have long been known to be chitin based materials formed as cellular extensions, we have found a nanostructured layer of chitin in the cuticle of the wing of the dog day annual cicada Tibicen tibicens, which may be the scaffold for the nanocone arrays found on the wing. We also use this process to examine

  19. SEM characterization of anatomical variation in chitin organization in insect and arthropod cuticles.

    Science.gov (United States)

    Chandran, Rakkiyappan; Williams, Lee; Hung, Albert; Nowlin, Kyle; LaJeunesse, Dennis

    2016-03-01

    The cuticles of insects and arthropods have some of the most diverse material properties observed in nature, so much so that it is difficult to imagine that all cutciles are primarily composed of the same two materials: a fibrous chitin network and a matrix composed of cuticle proteins. Various factors contribute to the mechanical and optical properties of an insect or arthropod cuticle including the thickness and composition. In this paper, we also identified another factor that may contribute to the optical, surface, and mechanical properties of a cuticle, i.e. the organization of chitin nanofibers and chitin fiber bundles. Self-assembled chitin nanofibers serve as the foundation for all higher order chitin structures in the cuticles of insects and other arthropods via interactions with structural cuticle proteins. Using a technique that enables the characterization of chitin organization in the cuticle of intact insects and arthropod exoskeletons, we demonstrate a structure/function correlation of chitin organization with larger scale anatomical structures. The chitin scaffolds in cuticles display an extraordinarily diverse set of morphologies that may reflect specific mechanical or physical properties. After removal of the proteinaceous and mineral matrix of a cuticle, we observe using SEM diverse nanoscale and micro scale organization of in-situ chitin in the wing, head, eye, leg, and dorsal and ventral thoracic regions of the periodical cicada Magicicada septendecim and in other insects and arthropods. The organization of chitin also appears to have a significant role in the organization of nanoscale surface structures. While microscale bristles and hairs have long been known to be chitin based materials formed as cellular extensions, we have found a nanostructured layer of chitin in the cuticle of the wing of the dog day annual cicada Tibicen tibicens, which may be the scaffold for the nanocone arrays found on the wing. We also use this process to examine

  20. Arthropods in Natural Communities in Mescal Agave (Agave durangensis Gentry in an Arid Zone

    Directory of Open Access Journals (Sweden)

    Maria P. Gonzalez-Castillo

    2011-01-01

    Full Text Available Problem statement: The arthropods have a very important role in the arid zones due to their interactions with many organism and because they constituted an important element in the structure of the plant community. Nevertheless their importance there are few knowledge about the community of arthropods associated to vegetation in arid zones in the North of Mexico. The present study had the objective of determining the abundance, richness and diversity of arthropods in three localities where there are natural populations of mescal agave in the State of Durango, Mexico. Approach: In order to know the structure community of the arthropods associated to the mescal agave, we perform a sampling schedule during March 2008 to November 2010 by direct collection, using transects in three different localities with the presence of mescal agave. The relative abundance, species richness, Shannon’s diversity index, Pielou’s Index of evenness, Jaccard’s similitude and Simpson’s dominance indexes were determined. Results: A total of 4665 individual arthropods associated to mescal agave corresponding to 39 species were found. El Mezquital had the highest abundance and relative abundance (44.1% with 29 species. The mean species abundance was not significantly different between localities using Turkey’s test. The highest density per unit of area was found in El Mezquital (La Brena had the highest species diversity (1.89, evenness (0.61 and dominance (0.78. At the taxon level, Hymenoptera had the highest number of species represented (14, followed by Coleoptera (9 and hemiptera (5, with the remaining taxons with four, two and one species each. Conclusion: The greatest similitude was observed between La Brena and El Mezquital (46% which shared seven taxons, while the least similitude was observed between El Venado and La Brena (29%. Dominance/diversity curves are presented for each locality. The species Caulotops sp., Acutaspis agavis, Chilorus sp

  1. Vector WIMP Miracle

    CERN Document Server

    Abe, Tomohiro; Matsumoto, Shigeki; Seto, Osamu

    2012-01-01

    Weakly interacting massive particle (WIMP) is well known to be a good candidate for dark matter, and it is also predicted by many new physics models beyond the standard model at the TeV scale. We found that, if the WIMP is a vector particle (spin one particle) which is associated with some gauge symmetry broken at the TeV scale, the higgs mass is often predicted to be 120--125 GeV, which is very consistent with the result of higgs searches recently reported by ATLAS and CMS collaborations at the Large Hadron Collider experiment. In this letter, we consider the vector WIMP using a non-linear sigma model in order to confirm this result as general as possible in a bottom-up approach. Near-future prospects to detect the vector WIMP at both direct and indirect detection experiments of dark matter are also discussed.

  2. Vector financial rogue waves

    Science.gov (United States)

    Yan, Zhenya

    2011-11-01

    The coupled nonlinear volatility and option pricing model presented recently by Ivancevic is investigated, which generates a leverage effect, i.e., stock volatility is (negatively) correlated to stock returns, and can be regarded as a coupled nonlinear wave alternative of the Black-Scholes option pricing model. In this Letter, we analytically propose vector financial rogue waves of the coupled nonlinear volatility and option pricing model without an embedded w-learning. Moreover, we exhibit their dynamical behaviors for chosen different parameters. The vector financial rogue wave (rogon) solutions may be used to describe the possible physical mechanisms for the rogue wave phenomena and to further excite the possibility of relative researches and potential applications of vector rogue waves in the financial markets and other related fields.

  3. Vector WIMP miracle

    Science.gov (United States)

    Abe, Tomohiro; Kakizaki, Mitsuru; Matsumoto, Shigeki; Seto, Osamu

    2012-07-01

    Weakly interacting massive particle (WIMP) is well known to be a good candidate for dark matter, and it is also predicted by many new physics models beyond the standard model at the TeV scale. We found that, if the WIMP is a vector particle (spin-one particle) which is associated with some gauge symmetry broken at the TeV scale, the Higgs mass is often predicted to be 120-125 GeV, which is very consistent with the result of Higgs searches recently reported by ATLAS and CMS Collaborations at the Large Hadron Collider experiment. In this Letter, we consider the vector WIMP using a non-linear sigma model in order to confirm this result as general as possible in a bottom-up approach. Near-future prospects to detect the vector WIMP at both direct and indirect detection experiments of dark matter are also discussed.

  4. Boosting Support Vector Machines

    Directory of Open Access Journals (Sweden)

    Elkin Eduardo García Díaz

    2006-11-01

    Full Text Available En este artículo, se presenta un algoritmo de clasificación binaria basado en Support Vector Machines (Máquinas de Vectores de Soporte que combinado apropiadamente con técnicas de Boosting consigue un mejor desempeño en cuanto a tiempo de entrenamiento y conserva características similares de generalización con un modelo de igual complejidad pero de representación más compacta./ In this paper we present an algorithm of binary classification based on Support Vector Machines. It is combined with a modified Boosting algorithm. It run faster than the original SVM algorithm with a similar generalization error and equal complexity model but it has more compact representation.

  5. Matrix vector analysis

    CERN Document Server

    Eisenman, Richard L

    2005-01-01

    This outstanding text and reference applies matrix ideas to vector methods, using physical ideas to illustrate and motivate mathematical concepts but employing a mathematical continuity of development rather than a physical approach. The author, who taught at the U.S. Air Force Academy, dispenses with the artificial barrier between vectors and matrices--and more generally, between pure and applied mathematics.Motivated examples introduce each idea, with interpretations of physical, algebraic, and geometric contexts, in addition to generalizations to theorems that reflect the essential structur

  6. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...

  7. Scalar-Vector Bootstrap

    CERN Document Server

    Rejon-Barrera, Fernando

    2015-01-01

    We work out all of the details required for implementation of the conformal bootstrap program applied to the four-point function of two scalars and two vectors in an abstract conformal field theory in arbitrary dimension. This includes a review of which tensor structures make appearances, a construction of the projectors onto the required mixed symmetry representations, and a computation of the conformal blocks for all possible operators which can be exchanged. These blocks are presented as differential operators acting upon the previously known scalar conformal blocks. Finally, we set up the bootstrap equations which implement crossing symmetry. Special attention is given to the case of conserved vectors, where several simplifications occur.

  8. Analysis in Vector Spaces

    CERN Document Server

    Akcoglu, Mustafa A; Ha, Dzung Minh

    2011-01-01

    A rigorous introduction to calculus in vector spaces The concepts and theorems of advanced calculus combined with related computational methods are essential to understanding nearly all areas of quantitative science. Analysis in Vector Spaces presents the central results of this classic subject through rigorous arguments, discussions, and examples. The book aims to cultivate not only knowledge of the major theoretical results, but also the geometric intuition needed for both mathematical problem-solving and modeling in the formal sciences. The authors begin with an outline of key concepts, ter

  9. Mineral cycling in soil and litter arthropod food chains. Progress report, November 1, 1979-October 31, 1980

    International Nuclear Information System (INIS)

    Recent progress and current status are reported for research concerned with mineral element dynamics in soil arthropod food chains. Research is performed within the larger context of terrestrial decomposition systems, in which soil arthropods may act as regulators of nutrient dynamics during decomposition. Research is measuring rates of nutrient accumulation and excretion by using radioactive tracer techniques with radioactive analogs of nutrients. Experimental measurement of radioactive tracer excretion and nutrient element pools are reported for soil microarthropods, using new methods of counting and microprobe elemental analysis. Research on arthropod-fungal relations is utilizing high-efficiency extraction followed by dissection of 13 x 13 cm soil blocks. A two-component excretion model is reported for Cobalt-60 in earthworms (Eisenia foetida), demonstrating that no assimilation of cobalt occurs from the mineral soil fraction but is entirely from organic matter. Collection of data sets on soil arthropod communities and abundances is completed

  10. A study on the effects of golf course organophosphate and carbamate pesticides on endangered, cave-dwelling arthropods Kauai, Hawaii

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Three endemic species, two arthropods and one isopod, are present in the Kauai caves. These species are critical components of the cave ecosystems and are possibly...

  11. Search for potential vectors of ‘Candidatus Liberibacter solanacearum’: population dynamics in host crops

    Directory of Open Access Journals (Sweden)

    Gabriela Teresani

    2015-03-01

    Full Text Available Candidatus Liberibacter solanacearum’ has recently been reported to be associated with vegetative disorders and economic losses in carrot and celery crops in Spain. The bacterium is a carrot seedborne pathogen and it is transmitted by psyllid vector species. From 2011 to 2014 seasonal and occasional surveys in carrot, celery and potato plots were performed. The sticky plant method was used to monitor the arthropods that visited the plants. The collected arthropods were classified into Aphididae and Cicadellidae, and the superfamily Psylloidea was identified to the species level. The superfamily Psylloidea represented 35.45% of the total arthropods captured on celery in Villena and 99.1% on carrot in Tenerife (Canary Islands. The maximum flight of psyllid species was in summer, both in mainland Spain and the Canary Islands, reaching a peak of 570 specimens in August in Villena and 6,063 in July in Tenerife. The main identified psyllid species were as follows: Bactericera trigonica Hodkinson, B. tremblayi Wagnerand B. nigricornis Förster. B. trigonica represented more than 99% of the psyllids captured in the Canary Islands and 75% and 38% in 2011 and 2012 in Villena, respectively. In addition, Trioza urticae Linnaeus, Bactericera sp.,Ctenarytaina sp., Cacopsylla sp., Trioza sp. and Psylla sp. were captured. ‘Ca. L. solanacearum’ targets were detected by squash real-time PCR in 19.5% of the psyllids belonging to the different Bactericera species. This paper reports at least three new psyllid species that carry the bacterium and can be considered as potential vectors.

  12. Adult carrion arthropod community in a tropical rainforest of Malaysia: analysis on three common forensic entomology animal models.

    Science.gov (United States)

    Azwandi, A; Nina Keterina, H; Owen, L C; Nurizzati, M D; Omar, B

    2013-09-01

    Decomposing carrion provides a temporary microhabitat and food source for a distinct community of organisms. Arthropods constitute a major part of this community and can be utilized to estimate the postmortem interval (PMI) of cadavers during criminal investigations. However, in Malaysia, knowledge of carrion arthropod assemblages and their succession is superficial. Therefore, a study on three types of forensic entomology animal model was conducted from 27 September 2010 to 28 October 2010 in a tropical rainforest at National University of Malaysia, Bangi, Selangor, Malaysia. Over one month collections of arthropods were made on nine animal carcasses: three laboratory rats (Rattus norvegicus, mean weight: 0.508 ± 0.027 kg), three rabbits (Oryctolagus cuniculus, mean weight: 2.538 ± 0.109 kg) and three long tailed macaque (Macaca fascicularis, mean weight: 5.750 ± 0.551 kg). A total of 31,433 arthropods belonging to eight orders and twenty-eight families were collected from all carcasses. Among 2924 of adults flies collected, approximately 19% were calliphorids with Chrysomya megacephala (Fabricius, 1794) being the most abundant. Arthropod taxon richness was lower on rat carcasses compared to that of rabbit and monkey carcasses, and this was more apparent during the first week of decomposition. However, there were no significant differences in Shannon-Weiner index (H'), Simpson dominance index (C) and Pielou's Evenness index (J) between different animal model. The arthropod assemblages associated to animal model were different significantly (p<0.05) while decomposition stage was a significant factor influencing insect assemblages (p<0.05). Analysis on the arthropods succession indicated that some taxa have a clear visitation period while the others, particularly Coleoptera, did not show a clear successional pattern thus require futher insect succession study. Although human bodies were not possible for the succession study, most of the arthropods collected are

  13. Short-term effects of different genetically modified maize varieties on arthropod food web properties: an experimental field assessment

    OpenAIRE

    Szénási, Ágnes; Pálinkás, Zoltán; Zalai, Mihály; Schmitz, Oswald J.; Balog, Adalbert

    2014-01-01

    There is concern that genetically modified (GM) plants may have adverse affects on the arthropod biodiversity comprising agricultural landscapes. The present study report on a two year field experimental test of whether four different genotypic lines, some are novel with no previous field tests, of GM maize hybrids alter the structure of arthropod food webs that they harbour, relative to non-GM maize (control) that is widely used in agriculture. The different GM genotypes produced either Bt t...

  14. Cysteine-Free Proteins in the Immunobiology of Arthropod-Borne Diseases

    Directory of Open Access Journals (Sweden)

    J. Santiago Mejia

    2010-01-01

    Full Text Available One approach to identify epitopes that could be used in the design of vaccines to control several arthropod-borne diseases simultaneously is to look for common structural features in the secretome of the pathogens that cause them. Using a novel bioinformatics technique, cysteine-abundance and distribution analysis, we found that many different proteins secreted by several arthropod-borne pathogens, including Plasmodium falciparum, Borrelia burgdorferi, and eight species of Proteobacteria, are devoid of cysteine residues. The identification of three cysteine-abundance and distribution patterns in several families of proteins secreted by pathogenic and nonpathogenic Proteobacteria, and not found when the amino acid analyzed was tryptophan, provides evidence of forces restricting the content of cysteine residues in microbial proteins during evolution. We discuss these findings in the context of protein structure and function, antigenicity and immunogenicity, and host-parasite relationships.

  15. Standardization and optimization of arthropod inventories-the case of Iberian spiders

    DEFF Research Database (Denmark)

    Bondoso Cardoso, Pedro Miguel

    2009-01-01

    Conservation of species requires accurate knowledge on their distribution. For most groups this can only be achieved through targeted biodiversity assessment programs that must explicitly incorporate comparability and efficiency in their definition. These require the standardization and...... optimization of sampling protocols, especially for mega-diverse arthropod taxa. This study had two objectives: (1) propose guidelines and statistical methods to improve the standardization and optimization of arthropod inventories, and (2) to propose a standardized and optimized protocol for Iberian spiders...... based on such guidelines and methods. Definition of the protocol has the following four steps. Firstly, the evaluation of the source data to ensure that the protocol is based on close to complete sampling of a number of sites. Secondly, optimizing the effort per collecting method, using an iterative...

  16. Disturbance In Dry Coastal Dunes Promotes Diversity Of Plants And Arthropods

    DEFF Research Database (Denmark)

    Brunbjerg, Ane Kirstine; Jørgensen, Gorm Pilgaard; Nielsen, Kristian Mandsberg;

    2015-01-01

    Naturally disturbed coastal dunes have become strongly reduced during the last century due to the cessation of grazing by domestic herbivores, dune stabilization initiatives, and increasing nitrogen deposition, all promoting encroachment by grasses, shrubs and woody plants. We assessed the effects...... of three disturbance types (burning, trampling and blowouts) on plant and arthropod species richness and composition in dry coastal dunes in Jutland, Denmark. Environmental variables, plant presence–absence and arthropod abundance were measured in 150 1 × 2 m plots along transects in blowouts, burned areas......, trampled paths and their paired controls. We used Nonmetric Multidimensional Scaling (NMDS) ordination to assess differences in species composition of disturbed areas and controls. Ordination scores were used as response variables in Linear Mixed Effect (LME) models to test for the effects of disturbances...

  17. The characterization of new hormonal systems in arthropods with a focus on neuropeptide GPCRs

    DEFF Research Database (Denmark)

    Stafflinger, Elisabeth

    Neuropeptides and their G-protein coupled receptors (GPCRs) occupy a high hierarchical position in the physiology of animals, because they steer important processes such as reproduction, development, and behaviour. Within the last nine years, several genomes have been sequenced providing the basis...... of genome comparisons and analysis. This yields new insights in GPCR evolution and ligand co-evolution, but also uncovers many new hormonal systems. In this thesis, I characterized a group of neuropeptide GPCRs and their ligands in arthropods and investigated GPCR evolution and co-evolution of their ligands...... is an independent signalling system. The work in this thesis describes unknown hormonal systems in arthropods and gives insights into their evolution. Furthermore, it shows that neuropeptide/receptor couples can easily duplicate or disappear during insect evolution....

  18. Background internal dose rates of earthworm and arthropod species in the forests of Aomori, Japan

    International Nuclear Information System (INIS)

    We measured naturally occurring radionuclides in samples from an earthworm species and 11 arthropod species collected in coniferous forests in Rokkasho, Aomori, Japan, to assess background internal radiation dose rates. The rates were calculated from the measured concentrations of the radionuclides and dose coefficients from the literature. The mean internal dose rate of composite earthworm samples was 0.35 μGy h-1, whereas the mean dose rates of the arthropod samples ranged from 36 nGy h-1 to 0.79 μGy h-1. Polonium-210 was the radionuclide with the highest contribution to the internal dose rate for all the species, except the longhorn beetle. (author)

  19. Vector-borne Infections

    Centers for Disease Control (CDC) Podcasts

    2011-04-18

    This podcast discusses emerging vector-borne pathogens, their role as prominent contributors to emerging infectious diseases, how they're spread, and the ineffectiveness of mosquito control methods.  Created: 4/18/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 4/27/2011.

  20. Singular Vectors' Subtle Secrets

    Science.gov (United States)

    James, David; Lachance, Michael; Remski, Joan

    2011-01-01

    Social scientists use adjacency tables to discover influence networks within and among groups. Building on work by Moler and Morrison, we use ordered pairs from the components of the first and second singular vectors of adjacency matrices as tools to distinguish these groups and to identify particularly strong or weak individuals.

  1. Calculus with vectors

    CERN Document Server

    Treiman, Jay S

    2014-01-01

    Calculus with Vectors grew out of a strong need for a beginning calculus textbook for undergraduates who intend to pursue careers in STEM. fields. The approach introduces vector-valued functions from the start, emphasizing the connections between one-variable and multi-variable calculus. The text includes early vectors and early transcendentals and includes a rigorous but informal approach to vectors. Examples and focused applications are well presented along with an abundance of motivating exercises. All three-dimensional graphs have rotatable versions included as extra source materials and may be freely downloaded and manipulated with Maple Player; a free Maple Player App is available for the iPad on iTunes. The approaches taken to topics such as the derivation of the derivatives of sine and cosine, the approach to limits, and the use of "tables" of integration have been modified from the standards seen in other textbooks in order to maximize the ease with which students may comprehend the material. Additio...

  2. The value of urban vacant land to support arthropod biodiversity and ecosystem services.

    Science.gov (United States)

    Gardiner, Mary M; Burkman, Caitlin E; Prajzner, Scott P

    2013-12-01

    The expansion of urban areas is occurring globally, but not all city neighborhoods are gaining population. Because of economic decline and the recent foreclosure crisis, many U.S. cities are demolishing abandoned residential structures to create parcels of vacant land. In some cities, weak housing markets have, or will likely, recover in the near term, and these parcels will be redeveloped. However, in other cities, large numbers of abandoned parcels have no significant market value and no likelihood of near-term redevelopment. The creation of these vacated green spaces could offer opportunities to preserve declining species, restore ecosystem functions, and support diverse ecosystem services. Arthropods are an important indicator of the ability of urban vacant land to serve multiple functions, from conservation to food production. Across Europe, vacant lands have been found to support a diversity of rare species, and similar examinations of arthropods within this habitat are underway in the United States. In addition, using vacant land as a resource for local food production is growing rapidly worldwide. Arthropods play key roles in the sustainability of food production in cities, and land conversion to farming has been found to influence their community composition and function. A greater focus on quantifying the current ecological value of vacant land and further assessment of how changes in its ecosystem management affect biodiversity and ecosystem processes is clearly needed. Herein, we specifically focus on the role of arthropods in addressing these priorities to advance our ecological understanding of the functional role of vacant land habitats in cities. PMID:24468552

  3. Crystallographic texture of the arthropod cuticle using synchrotron wide angle X-ray diffraction

    OpenAIRE

    Sawalmih, Ali al-

    2007-01-01

    Arthropods, which include the crustaceans (e.g. crabs, lobsters, isopods), insects, arachnids (e.g. spiders, scorpions, ticks, mites), and several lesser groups, account for approximately 80 percent of all known animal species. The outer covering of these animals is referred to as exoskeleton or cuticle, and it covers the entire body of the animal. It has remarkable mechanical properties which provide structural support to the body, armor against loads that are externally imposed by predators...

  4. Ground Arthropod Attacks on Groundnut Arachis hypogaea L in Burkina Faso

    OpenAIRE

    Dicko, IO.; Troaoré, S.; Traoré, D.; Dao, B.

    1999-01-01

    Studies were conducted in five districts of Burkina Faso, West Africa from November to December, 1996. The objectives aimed at establishing spatial distribution and quantifying the level of damages on peanut pods by soil arthropods, termites and millepedes. Twenty seven samples of 100 pods each were taken from farmers' stocks in each district, which made a total of 135 pod samples examined. Damage was determined in each district by counting scarified pods by termites and perforated pods by mi...

  5. Self-referent phenotype matching and its role in female mate choice in arthropods

    Institute of Scientific and Technical Information of China (English)

    Carie B.WEDDLE; John HUNT; Scott K.SAKALUK

    2013-01-01

    A growing body of empirical evidence shows that females of many animal species gain benefits by mating polyandrously,and often prefer to mate with novel males over previous mates.Although a female preference for novel males has been demonstrated for multiple animal taxa,the mechanisms used by females to discriminate between novel and previous mates remain largely unknown.However,recent studies suggest that in decorated crickets Gryllodes sigillatus,females actually imbue males with their own chemical cues,known as cuticular hydrocarbons (CHCs) during mating,and utilize chemosensory self-referencing to recognize recent mates.Here we review evidence that self-referent phenotype matching is a widespread mechanism of recognition in arthropods,and explore how CHCs are used to facilitate mate-choice decisions.There is substantial evidence that CHCs are used as recognition cues to discriminate between species,kin,sexes,mates,individuals,and self and non-self,and are used to facilitate mate-choice decisions in a wide range of arthropod taxa.There is also evidence that CHCs are often transferred between individuals during direct physical contact,including copulation.Chemosensory self-referencing via cuticular hydrocarbons could provide a simple,but reliable mechanism for identifying individuals from previous mating encounters.This mechanism does not require any specialized cognitive abilities because an individual's phenotype is always available for reference.Given the ubiquitous use of CHCs among arthropods,chemosensory self-referencing may be a widespread mechanism used by female arthropods to facilitate female mate-choice decisions and to enhance opportunities for polyandry.

  6. Self-referent phenotype matching and its role in female mate choice in arthropods

    Directory of Open Access Journals (Sweden)

    Carie B. WEDDLE, John HUNT, Scott K. SAKALUK

    2013-04-01

    Full Text Available A growing body of empirical evidence shows that females of many animal species gain benefits by mating polyandrously, and often prefer to mate with novel males over previous mates. Although a female preference for novel males has been demonstrated for multiple animal taxa, the mechanisms used by females to discriminate between novel and previous mates remain largely unknown. However, recent studies suggest that in decorated crickets Gryllodes sigillatus, females actually imbue males with their own chemical cues, known as cuticular hydrocarbons (CHCs during mating, and utilize chemosensory self-referencing to recognize recent mates. Here we review evidence that self-referent phenotype matching is a widespread mechanism of recognition in arthropods, and explore how CHCs are used to facilitate mate-choice decisions. There is substantial evidence that CHCs are used as recognition cues to discriminate between species, kin, sexes, mates, individuals, and self and non-self, and are used to facilitate mate-choice decisions in a wide range of arthropod taxa. There is also evidence that CHCs are often transferred between individuals during direct physical contact, including copulation. Chemosensory self-referencing via cuticular hydrocarbons could provide a simple, but reliable mechanism for identifying individuals from previous mating encounters. This mechanism does not require any specialized cognitive abilities because an individual’s phenotype is always available for reference. Given the ubiquitous use of CHCs among arthropods, chemosensory self-referencing may be a widespread mechanism used by female arthropods to facilitate female mate-choice decisions and to enhance opportunities for polyandry [Current Zoology 59 (2: 239-248, 2013].

  7. Spatial variation of arthropod communities in virgin and managed sites in the Kibale Forest, western Uganda.

    OpenAIRE

    Nummelin, M.; Zilihona, I.J.E.

    2004-01-01

    http://www.elsevier.com/locate/issn/03781127 The structure of arthropod communities in the forest floor vegetation in four differently managed forest sites (virgin forest, lightly selectively logged, heavily selectively logged, and exotic Pinus caribaea plantation) in Kibale Forest National Park, western Uganda, was studied by sweep net between March and May 1985 and July 1995. For the analysis three (or four) 800 sweeps samples were collected from each habitat. In the samples eig...

  8. Diversity of the arthropod fauna in organically grown garlic intercropped with fodder radish.

    OpenAIRE

    Silva, André Wagner Barata; Haro, Marcelo Mendes; Silveira, Luís Cláudio Paterno

    2012-01-01

    The cultivation of garlic faces several problems, which include pest attack, and the diversification of habitat through intercropping with attractive plants comes up as a method to pest management. The objective of this research was to verify the effect of the association of garlic with fodder radish on richness, abundance and diversity of arthropods under organic production system in Lavras, MG, Brazil. The treatments were composed of garlic in monoculture and garlic in association with fodd...

  9. Arthropod visual predators in the early pelagic ecosystem: evidence from the Burgess Shale and Chengjiang biotas

    OpenAIRE

    Vannier, J; García-Bellido, D.C.; Hu, S.-X.; Chen, A.-L.

    2009-01-01

    Exceptional fossil specimens with preserved soft parts from the Maotianshan Shale (ca 520 Myr ago) and the Burgess Shale (505 Myr ago) biotas indicate that the worldwide distributed bivalved arthropod Isoxys was probably a non-benthic visual predator. New lines of evidence come from the functional morphology of its powerful prehensile frontal appendages that, combined with large spherical eyes, are thought to have played a key role in the recognition and capture of swimming or epibenthic prey...

  10. A Cambrian micro-lobopodian and the evolution of arthropod locomotion and reproduction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The evolutionary success of arthropods, the most abundant and diverse animal group, is mainly based on their segmented body and jointed appendages, features that had evolved most likely already before the Cambrian. The first arthropod-like animals, the lobopodians from the Early Cambrian, were unsclerotized and worm-like, and they had unjointed tubular legs. Here we describe the first three-dimensionally preserved Cambrian lobopodian. The material presented of Orstenotubulus evamuellerae gen. et sp. nov. is the smallest and youngest of a lobopodian known. O. evamuellerae shows strikingly detailed similarities to Recent tardigrades and/or onychophorans in its cellular-structured cuticle and the telescopic spines. It also shows similarities to other, longer known lobopodians, but which are ten times as large as the new form. These similarities include the finely annulated body and legs, which is characteristic also for Recent onychophorans, and paired humps continuing into spines situated dorsally to the leg insertions, a feature lacking in the extant forms. The morphology of O. evamuellerae not only elucidates our knowledge about lobopodians, but also aids in a clearer picture of the early evolution of arthropods. An example is the single ventral gonopore between a limb pair of O. evamuellerae, which indicates that a single gonopore, as developed in onychophorans, tardigrades, pentastomids, myriapods and insects, might represent the plesiomorphic state for Arthropoda, while the paired state in chelicerates and crustaceans was convergently achieved. Concerning life habits, the lateral orientation of the limbs and their anchoring spines of the new lobopodian imply that early arthropods were crawlers rather than walkers.

  11. [Diversity and stability of arthropod community in peach orchard under effects of ground cover vegetation].

    Science.gov (United States)

    Jiang, Jie-xian; Wan, Nian-feng; Ji, Xiang-yun; Dan, Jia-gui

    2011-09-01

    A comparative study was conducted on the arthropod community in peach orchards with and without ground cover vegetation. In the orchard with ground cover vegetation, the individuals of beneficial, neutral, and phytophagous arthropods were 1.48, 1.84 and 0.64 times of those in the orchard without ground cover vegetation, respectively, but the total number of arthropods had no significant difference with that in the orchard without ground cover vegetation. The species richness, Shannon's diversity, and Pielou's evenness index of the arthropods in the orchard with ground cover vegetation were 83.733 +/- 4.932, 4.966 +/- 0.110, and 0.795 +/- 0.014, respectively, being significantly higher than those in the orchard without ground cover vegetation, whereas the Berger-Parker's dominance index was 0.135 +/- 0.012, being significantly lower than that (0.184 +/- 0.018) in the orchard without ground cover vegetation. There were no significant differences in the stability indices S/N and Sd/Sp between the two orchards, but the Nn/Np, Nd/Np, and Sn/Sp in the orchard with ground cover vegetation were 0.883 +/- 0.123. 1714 +/- 0.683, and 0.781 +/- 0.040, respectively, being significantly higher than those in the orchard without ground cover vegetation. Pearson's correlation analysis indicated that in the orchard with ground cover vegetation, the Shannon's diversity index was significantly negatively correlated with Nd/Np, Sd/Sp, and S/N but had no significant correlations with Nn/Np and Sn/Sp, whereas in the orchard without ground cover vegetation, the diversity index was significantly positively correlated with Nn/Np and Nd/Np and had no significant correlations with Sd/Sp, Sn/Sp, and S/N.

  12. Trophic structure of arthropods in Starling nests matter to blood parasites and thereby to nestling development

    OpenAIRE

    Wolfs, Peter H. J.; Lesna, Izabela K.; Sabelis, Maurice W.; Komdeur, Jan; Bairlein, F.

    2012-01-01

    Nestling development and long-term survival in many bird species depend on factors such as parental feeding, time of breeding and environmental conditions. However, little research has been carried out on the effect of ectoparasites on nestling development, and no research on the impact of the trophic structure of arthropods inhabiting the nest (combined effects of ectoparasitic mites and predatory mites feeding on ectoparasites). We assess nestling development of European Starlings (Sturnus ...

  13. New euthycarcinoids and an enigmatic arthropod from the British coal measures

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, H.M.; Almond, J.E. [Univrsity of Maryland, College Park, MD (USA). Dept. Entomology

    2001-07-01

    Two new species of euthycarcinoids (Arthropoda), Kottixerxes anglicus sp. nov. and Smithixerxes pustulosus sp. nov., are described from the Coal Measures of Westhoughton, Lancashire and Coseley, West Midlands (Westphalian A and B respectively). Both genera are previously known from Mazon Creek, USA (Westphalian D). An additional, enigmatic arthropod with possible euthycarcinoid affinities, Arthrogyrinus platyurus gen. et sp. nov., is described from Coseley. Hypotheses concerning the phylogenetic position of euthycarcinoids are critically reviewed.

  14. Effects of Timing of Grazing on Arthropod Communities in Semi-Natural Grasslands

    OpenAIRE

    Lenoir, Lisette; Lennartsson, Tommy

    2010-01-01

    Arthropod communities were investigated in two Swedish semi-natural grasslands, each subject to two types of grazing regime: conventional grazing from May to September (continuous grazing) and traditional late management from mid-July (late grazing). Pitfall traps were used to investigate abundance of carabids, spiders, and ants over the grazing season. Ant abundance was also measured by mapping nest density during three successive years. Small spiders, carabids and ants (Myrmica spp.) were m...

  15. Arthropods of Steel Creek, Buffalo National River, Arkansas. III. Heteroptera (Insecta: Hemiptera)

    OpenAIRE

    Skvarla, Michael Joseph; Fisher, Danielle M.; Dowling, Ashley P.G.

    2016-01-01

    Abstract Background This is the third in a series of papers detailing the terrestrial arthropods collected during an intensive survey of a site near Steel Creek campground along the Buffalo National River in Arkansas. The survey was conducted over a period of eight and a half months using twelve trap types – Malaise traps, canopy traps (upper and lower collector), Lindgren multifunnel traps (black, green, and purple), pan traps (blue, purple, red, white, and yellow), and pitfall traps – and B...

  16. Terrestrial arthropods of Steel Creek, Buffalo National River, Arkansas. II. Sawflies (Insecta: Hymenoptera: " Symphyta ")

    OpenAIRE

    Skvarla, Michael Joseph; Smith, David R.; Fisher, Danielle M.; Dowling, Ashley P.G.

    2016-01-01

    Abstract Background This is the second in a series of papers detailing the terrestrial arthropods collected during an intensive survey of a site near Steel Creek campground along the Buffalo National River in Arkansas. The survey was conducted over a period of eight and a half months using twelve trap types – Malaise traps, canopy traps (upper and lower collector), Lindgren multifunnel traps (black, green, and purple), pan traps (blue, purple, red, white, and yellow), and pitfall traps – and ...

  17. The effects of land-use change on arthropod richness and abundance on Santa Maria Island (Azores)

    DEFF Research Database (Denmark)

    Meijer, Seline S.; Whittaker, Robert J.; Borges, P. A. V.

    2011-01-01

    We study how endemic, native and introduced arthropod species richness, abundance, diversity and community composition vary between four different habitat types (native forest, exotic forest of Cryptomeria japonica, semi-natural pasture and intensive pasture) and how arthropod richness and abunda......We study how endemic, native and introduced arthropod species richness, abundance, diversity and community composition vary between four different habitat types (native forest, exotic forest of Cryptomeria japonica, semi-natural pasture and intensive pasture) and how arthropod richness......), native, or introduced. The native forest had the highest values for species richness of Azorean endemics, SIEs and natives; and also had highest values of Azorean endemic diversity (Fisher’s alpha). In contrast, the intensive pasture had the lowest values for endemic and native species richness...... and diversity, but the highest values of total arthropod abundance and introduced species richness and diversity. Arthropod community composition was significantly different between the four habitat types. In the semi-natural pasture, the number of SIE species decreased with increasing distance from the native...

  18. Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

    Directory of Open Access Journals (Sweden)

    Debissa Lemessa

    Full Text Available Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests.

  19. Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

    Science.gov (United States)

    Lemessa, Debissa; Hambäck, Peter A; Hylander, Kristoffer

    2015-01-01

    Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests. PMID:25961306

  20. Bartonella species in small mammals and their potential vectors in Asia

    Institute of Scientific and Technical Information of China (English)

    Tawisa Jiyipong; Sathaporn Jittapalapong; Serge Morand; Jean-Marc Rolain

    2014-01-01

    In this article, authors review the current knowledge of Bartonella infection in small mammals including rodents, insectivores, bats and exotic small mammal pets and their vectors in Asia. Species of Bartonella are Gram-negative intracellular bacteria that infect erythrocytes of various mammalian and non-mammalian animals and mainly transmitted by blood sucking arthropod vectors. The genus Bartonella includes several species of important human diseases with severe clinical signs. Several new Bartonella species were isolated from rodents and other small mammals, and from human patients in Asia. Bartonella species are identified using standard polymerase chain reaction amplification and a sequencing targeting two housekeeping genes (gltA and rpoB) and the internal transcribed spacer fragment. Authors also discuss the implications in term of potential emerging zoonotic diseases.

  1. Bartonella species in small mammals and their potential vectors in Asia

    Institute of Scientific and Technical Information of China (English)

    Tawisa; Jiyipong; Sathaporn; Jittapalapong; Serge; Morand; Jean-Marc; Rolain

    2014-01-01

    In this article,authors review the current knowledge of Bartonella infection in small mammals including rodents,insectivores,bats and exotic small mammal pets and their vectors in Asia.Species of Bartonella are Gram-negative intracellular bacteria that infect erythrocytes of various mammalian and non-mammalian animals and mainly transmitted by blood sucking arthropod vectors.The genus Bartonella includes several species of important human diseases with severe clinical signs.Several new Bartonella species were isolated from rodents and other small mammals,and from human patients in Asia.Bartonella species are identified using standard polymerase chain reaction amplification and a sequencing targeting two housekeeping genes(glt.A and rpoB) and the internal transcribed spacer fragment.Authors also discuss the implications in term of potential emerging zoonotic diseases.

  2. Bartonella species in small mammals and their potential vectors in Asia

    Directory of Open Access Journals (Sweden)

    Tawisa Jiyipong

    2014-10-01

    Full Text Available In this article, authors review the current knowledge of Bartonella infection in small mammals including rodents, insectivores, bats and exotic small mammal pets and their vectors in Asia. Species of Bartonella are Gram-negative intracellular bacteria that infect erythrocytes of various mammalian and non-mammalian animals and mainly transmitted by blood sucking arthropod vectors. The genus Bartonella includes several species of important human diseases with severe clinical signs. Several new Bartonella species were isolated from rodents and other small mammals, and from human patients in Asia. Bartonella species are identified using standard polymerase chain reaction amplification and a sequencing targeting two housekeeping genes (gltA and rpoB and the internal transcribed spacer fragment. Authors also discuss the implications in term of potential emerging zoonotic diseases.

  3. A novel approach to the measurement of surfactant parameters in arthropod digestive juices.

    Science.gov (United States)

    Romih, Tea; Kogej, Ksenija; Drobne, Damjana

    2016-05-01

    In arthropods, the determination of two important parameters of digestive juices, i.e. the total surfactant concentration and the critical micelle concentration (CMC), is challenging due to small sample volumes and low surfactant concentrations. In this work, we report a successful implementation of potentiometric titrations using the surfactant ion-selective electrode (SISE) and the pyrene fluorescence method (PFM) for the determination of the total surfactant concentration and CMC in the digestive juice of terrestrial isopod crustaceans Porcellio scaber. Pooled digestive juice extracts of four (SISE) or two (PFM) animals were used per measurement run. In both cases, digestive juice extracts in 100μL of deionized water were sufficient for one measurement run. The total surfactant concentration of P. scaber digestive juice was determined to be 9.2±3.5mM and the CMC was approximately 90μM. Our work presents an important improvement towards easy CMC determination in small volume samples in comparison with the commonly used stalagmometric technique, where much larger sample volumes are usually needed. To date, the total surfactant concentration was not measured in the digestive juices of arthropods other than Homarus vulgaris, Astacus leptodactylus and Cancer pagurus, for which complex separation and analytical techniques were required. Our results obtained by SISE and PFM therefore present the first successful quantification of surfactants and their CMC in small volumes of arthropod digestive juice without prior separation or purification techniques. PMID:26969560

  4. Genetics-based interactions among plants, pathogens, and herbivores define arthropod community structure.

    Science.gov (United States)

    Busby, Posy E; Lamit, Louis J; Keith, Arthur R; Newcombe, George; Gehring, Catherine A; Whitham, Thomas G; Dirzo, Rodolfo

    2015-07-01

    Plant resistance to pathogens or insect herbivores is common, but its potential for indirectly influencing plant-associated communities is poorly known. Here, we test whether pathogens' indirect effects on arthropod communities and herbivory depend on plant resistance to pathogens and/or herbivores, and address the overarching interacting foundation species hypothesis that genetics-based interactions among a few highly interactive species can structure a much larger community. In a manipulative field experiment using replicated genotypes of two Populus species and their interspecific hybrids, we found that genetic variation in plant resistance to both pathogens and insect herbivores modulated the strength of pathogens' indirect effects on arthropod communities and insect herbivory. First, due in part to the pathogens' differential impacts on leaf biomass among the two Populus species and the hybrids, the pathogen most strongly impacted arthropod community composition, richness, and abundance on the pathogen-susceptible tree species. Second, we found similar patterns comparing pathogen-susceptible and pathogen-resistant genotypes within species. Third, within a plant species, pathogens caused a fivefold greater reduction in herbivory on insect-herbivore-susceptible plant genotypes than on herbivore-resistant genotypes, demonstrating that the pathogen-herbivore interaction is genotype dependent. We conclude that interactions among plants, pathogens, and herbivores can structure multitrophic communities, supporting the interacting foundation species hypothesis. Because these interactions are genetically based, evolutionary changes in genetic resistance could result in ecological changes in associated communities, which may in turn feed back to affect plant fitness.

  5. Effects of water addition on soil arthropods and soil characteristics in a precipitation-limited environment

    Science.gov (United States)

    Chikoski, Jennifer M.; Ferguson, Steven H.; Meyer, Lense

    2006-09-01

    We investigated the effect of water addition and season on soil arthropod abundance and soil characteristics (%C, %N, C:N, moisture, pH). The experimental design consisted of 24 groups of five boxes distributed within a small aspen stand in Saskatchewan, Canada. The boxes depressed the soil to create a habitat with suitable microclimate for soil arthropods, and by overturning boxes we counted soil arthropods during weekly surveys from April to September 1999. Soil samples were collected at two-month intervals and water was added once per week to half of the plots. Of the eleven recognizable taxonomic units identified, only mites (Acari) and springtails (Collembola) responded to water addition by increasing abundance, whereas ants decreased in abundance with water addition. During summer, springtail numbers increased with water addition, whereas pH was a stronger determinant of mite abundance. In autumn, springtails were positively correlated with water and negatively correlated with mites, whereas mite abundance was negatively correlated with increasing C:N ratio, positively correlated to water addition, and negatively correlated with springtail abundance. Although both mite and springtail numbers decreased in autumn with a decrease in soil moisture, mites became more abundant than springtails suggesting a predator-prey (mite-springtail) relationship. Water had a significant effect on both springtails and mites in summer and autumn supporting the assertion that prairie soil communities are water limited.

  6. Effect of brushwood transposition on the leaf litter arthropod fauna in a cerrado area

    Directory of Open Access Journals (Sweden)

    Paula Cristina Benetton Vergílio

    2013-10-01

    Full Text Available The results of ecological restoration techniques can be monitored through biological indicators of soil quality such as the leaf litter arthropod fauna. This study aimed to determine the immediate effect of brushwood transposition transferred from an area of native vegetation to a disturbed area, on the leaf litter arthropod fauna in a degraded cerrado area. The arthropod fauna of four areas was compared: a degraded area with signal grass, two experimental brushwood transposition areas, with and without castor oil plants, and an area of native cerrado. In total, 7,660 individuals belonging to 23 taxa were sampled. Acari and Collembola were the most abundant taxa in all studied areas, followed by Coleoptera, Diptera, Hemiptera, Hymenoptera, and Symphyla. The brushwood transposition area without castor oil plants had the lowest abundance and dominance and the highest diversity of all areas, providing evidence of changes in the soil community. Conversely, the results showed that the presence of castor oil plants hampered early succession, negatively affecting ecological restoration in this area.

  7. Discontinuous gas exchange in a tracheate arthropod, the pseudoscorpion Garypus californicus: Occurrence, characteristics and temperature dependence

    Directory of Open Access Journals (Sweden)

    John R.B. Lighton

    2002-11-01

    Full Text Available The discontinuous gas exchange cycle of the pseudoscorpion Garypus californicus, mean mass 5.9 mg, is rudimentary and is characterized by bursts of CO2 at frequencies ranging from 3.6 mHz at 15 °C to 13.3 mHz at 35 °C. The mean volume of CO2 emitted per burst is 3.6 µl g-1 at 25 °C, about a tenth of the amount emitted by tracheate arthropods with a well developed discontinuous gas exchange cycle. Interburst CO2 emission is high and increases with temperature, reaching near 45% of total CO2 production rate at 35 °C. No fluttering spiracle phase is evident. The metabolic rate of G. californicus at 25 °C (8.4 µW is typical of other arthropods. We infer from the high rate of interburst CO2 emission in G. californicus that trans-spiracular O2 partial pressure gradients are small and that spiracular conductance is correspondingly high, which may lead to high rates of respiratory water loss relative to arthropods with more stringent spiracular control and higher CO2 buffering capacity. The typical moist, hypogeal environments and small body sizes of pseudoscorpions correlate well with their respiratory physiology

  8. Short communication. Incidence of the OLIPE mass-trapping on olive non-target arthropods

    Energy Technology Data Exchange (ETDEWEB)

    Porcel, M.; Ruano, F.; Sanllorente, O.; Caballero, J. A.; Campos, M.

    2009-07-01

    Due to the widespread of mass-trapping systems for Bactrocera oleae (Gmelin) (Diptera: Tephritidae) control in organic olive cropping, an assessment of the impact on arthropods of the olive agroecosystem was undertaken for the OLIPE trap type. The sampling was carried out in Los Pedroches valley (Cordoba, southern Spain) in three different organic orchard sites. Six OLIPE traps baited with diammonium phosphate were collected from each site (18 in total) from July to November 2002 every 15 days on average. Additionally, in the latest sampling dates, half the traps were reinforced with pheromone to assess its impact on non-target arthropods. From an average of 43.0 catches per trap (cpt) of non-target arthropods during the whole sampling period, the highest number of captures corresponds to the Order Diptera (that represents a 68.5%), followed distantly by the family Formicidae (12.9%) and the Order Lepidoptera (10.4%). Besides the impact on ant populations, other beneficial groups were recorded such as parasitoids (Other Hymenoptera: 2.6%) and predators (Araneae: 1.0%; Neuroptera s.l.: 0.4%). Concerning the temporal distribution of catches, total captures peaked on July and had a slight increase at the beginning of autumn. No significant differences were observed between traps with and without pheromone. The results evidence that a considerable amount of non-specific captures could be prevented by improving the temporal planning of the mass-trapping system. (Author) 25 refs.

  9. Dating the arthropod tree based on large-scale transcriptome data.

    Science.gov (United States)

    Rehm, Peter; Borner, Janus; Meusemann, Karen; von Reumont, Björn M; Simon, Sabrina; Hadrys, Heike; Misof, Bernhard; Burmester, Thorsten

    2011-12-01

    Molecular sequences do not only allow the reconstruction of phylogenetic relationships among species, but also provide information on the approximate divergence times. Whereas the fossil record dates the origin of most multicellular animal phyla during the Cambrian explosion less than 540 million years ago(mya), molecular clock calculations usually suggest much older dates. Here we used a large multiple sequence alignment derived from Expressed Sequence Tags and genomes comprising 129genes (37,476 amino acid positions) and 117 taxa, including 101 arthropods. We obtained consistent divergence time estimates applying relaxed Bayesian clock models with different priors and multiple calibration points. While the influence of substitution rates, missing data, and model priors were negligible, the clock model had significant effect. A log-normal autocorrelated model was selected on basis of cross-validation. We calculated that arthropods emerged ~600 mya. Onychophorans (velvet worms) and euarthropods split ~590 mya, Pancrustacea and Myriochelata ~560 mya, Myriapoda and Chelicerata ~555 mya, and 'Crustacea' and Hexapoda ~510 mya. Endopterygote insects appeared ~390 mya. These dates are considerably younger than most previous molecular clock estimates and in better agreement with the fossil record. Nevertheless, a Precambrian origin of arthropods and other metazoan phyla is still supported. Our results also demonstrate the applicability of large datasets of random nuclear sequences for approximating the timing of multicellular animal evolution. PMID:21945788

  10. Interaction of the Lyme disease spirochete with its tick vector.

    Science.gov (United States)

    Caimano, Melissa J; Drecktrah, Dan; Kung, Faith; Samuels, D Scott

    2016-07-01

    Borrelia burgdorferi, the causative agent of Lyme disease (along with closely related genospecies), is in the deeply branching spirochete phylum. The bacterium is maintained in nature in an enzootic cycle that involves transmission from a tick vector to a vertebrate host and acquisition from a vertebrate host to a tick vector. During its arthropod sojourn, B. burgdorferi faces a variety of stresses, including nutrient deprivation. Here, we review some of the spirochetal factors that promote persistence, maintenance and dissemination of B. burgdorferi in the tick, and then focus on the utilization of available carbohydrates as well as the exquisite regulatory systems invoked to adapt to the austere environment between blood meals and to signal species transitions as the bacteria traverse their enzootic cycle. The spirochetes shift their source of carbon and energy from glucose in the vertebrate to glycerol in the tick. Regulation of survival under limiting nutrients requires the classic stringent response in which RelBbu controls the levels of the alarmones guanosine tetraphosphate and guanosine pentaphosphate (collectively termed (p)ppGpp), while regulation at the tick-vertebrate interface as well as regulation of protective responses to the blood meal require the two-component system Hk1/Rrp1 to activate production of the second messenger cyclic-dimeric-GMP (c-di-GMP). PMID:27147446

  11. Interaction of the Lyme disease spirochete with its tick vector

    Science.gov (United States)

    Caimano, Melissa J.; Drecktrah, Dan; Kung, Faith; Samuels, D. Scott

    2016-01-01

    Summary Borrelia burgdorferi , the causative agent of Lyme disease (along with closely related genospecies), is in the deeply branching spirochete phylum. The bacterium is maintained in nature in an enzootic cycle that involves transmission from a tick vector to a vertebrate host and acquisition from a vertebrate host to a tick vector. During its arthropod sojourn, B. burgdorferi faces a variety of stresses, including nutrient deprivation. Here, we review some of the spirochetal factors that promote persistence, maintenance and dissemination of B. burgdorferi in the tick, and then focus on the utilization of available carbohydrates as well as the exquisite regulatory systems invoked to adapt to the austere environment between blood meals and to signal species transitions as the bacteria traverse their enzootic cycle. The spirochetes shift their source of carbon and energy from glucose in the vertebrate to glycerol in the tick. Regulation of survival under limiting nutrients requires the classic stringent response in which RelBbu controls the levels of the alarmones guanosine tetraphosphate and guanosine pentaphosphate (collectively termed (p)ppGpp), while regulation at the tick–vertebrate interface as well as regulation of protective responses to the blood meal require the two-component system Hk1/Rrp1 to activate production of the second messenger cyclic-dimeric-GMP (c-di-GMP). PMID:27147446

  12. Novel methods for surveying reservoir hosts and vectors of Borrelia burgdorferi in Northern Minnesota

    Science.gov (United States)

    Seifert, Veronica Aili

    Lyme disease is the most prevalent tick-borne disease in North America and presents challenges to clinicians, researchers and the public in diagnosis, treatment and prevention. Lyme disease is caused by the spirochete, Borrelia burgdorferi, which is a zoonotic pathogen obligate upon hematophagous arthropod vectors and propagates in small mammal reservoir hosts. Identifying factors governing zoonotic diseases within regions of high-risk provides local health and agricultural agencies with necessary information to formulate public policy and implement treatment protocols to abate the rise and expansion of infectious disease outbreaks. In the United States, the documented primary reservoir host of Lyme disease is the white-footed mouse, Peromyscus leucopus, and the arthropod vector is the deer tick, Ixodes scapularis. Reducing the impact of Lyme disease will need novel methods for identifying both the reservoir host and the tick vector. The reservoir host, Peromyscus leucopus is difficult to distinguish from the virtually identical Peromyscus maniculatus that also is present in Northern Minnesota, a region where Lyme disease is endemic. Collection of the Ixodes tick, the Lyme disease vector, is difficult as this is season dependent and differs from year to year. This study develops new strategies to assess the extent of Borrelia burgdorferi in the local environment of Northern Minnesota. A selective and precise method to identify Peromyscus species was developed. This assay provides a reliable and definitive method to identify the reservoir host, Peromyscus leucopus from a physically identical and sympatric Peromyscus species, Peromyscus maniculatus. A new strategy to collect ticks for measuring the disbursement of Borrelia was employed. Students from local high schools were recruited to collect ticks. This strategy increased the available manpower to cover greater terrain, provided students with valuable experience in research methodology, and highlighted the

  13. Mechanical Vectors Enhance Fungal Entomopathogen Reduction of the Grasshopper Pest Camnula pellucida (Orthoptera: Acrididae).

    Science.gov (United States)

    Kistner, Erica J; Saums, Marielle; Belovsky, Gary E

    2015-02-01

    Mounting scientific evidence indicates that pathogens can regulate insect populations. However, limited dispersal and sensitivity to abiotic conditions often restricts pathogen regulation of host populations. While it is well established that arthropod biological vectors increase pathogen incidence in host populations, few studies have examined whether arthropod mechanical vectors (an organism that transmits pathogens but is not essential to the life cycle of the pathogen) influence host-pathogen dynamics. The importance of mechanical dispersal by ant scavengers, Formica fusca (L.), in a grasshopper-fungal entomopathogen system was investigated. We examined the ability of ants to mechanically disperse and transmit the pathogen, Entomophaga grylli (Fresenius) pathotype 1, to its host, the pest grasshopper Camnula pellucida (Scudder), in a series of laboratory experiments. Fungal spores were dispersed either externally on the ant's body surface or internally through fecal deposition. In addition, a third of all grasshoppers housed with fungal-inoculated ants became infected, indicating that ants can act as mechanical vectors of E. grylli. The effect of ant mechanical vectors on E. grylli incidence was also examined in a field experiment. Ant access to pathogen-exposed experimental grasshopper populations was restricted using organic ant repellent, thereby allowing us to directly compare mechanical and natural transmission. Ants increased grasshopper pathogen mortality by 58%, which led to greater pathogen reductions of grasshopper survival than natural transmission. Taken together, our results indicate that ants enhance E. grylli reduction of grasshopper pest numbers. Therefore, mechanical transmission of pathogens may be an important overlooking component of this grasshopper-fungal pathogen system. PMID:26308817

  14. Vector independent transmission of the vector-borne bluetongue virus

    NARCIS (Netherlands)

    Sluijs, van der M.T.W.; Smit, de A.J.; Moormann, R.J.M.

    2015-01-01

    Bluetongue is an economically important disease of ruminants. The causative agent, Bluetongue virus (BTV), is mainly transmitted by insect vectors. This review focuses on vector-free BTV transmission, and its epizootic and economic consequences. Vector-free transmission can either be vertical, from

  15. VECTOR BUNDLE, KILLING VECTOR FIELD AND PONTRYAGIN NUMBERS

    Institute of Scientific and Technical Information of China (English)

    周建伟

    1991-01-01

    Let E be a vector bundle over a compact Riemannian manifold M. We construct a natural metric on the bundle space E and discuss the relationship between the killing vector fields of E and M. Then we give a proof of the Bott-Baum-Cheeger Theorem for vector bundle E.

  16. Extended studies on the diversity of arthropod-pathogenic fungi in Austria and Poland

    Directory of Open Access Journals (Sweden)

    Cezary Tkaczyk

    2013-12-01

    Full Text Available Results of studies on diversity of arthropod-pathogenic fungi in selected habitats in Austria and Poland carried out in the years 2006-2007 and 2009-2010 are discussed. In total 47 species of entomopathogenic fungi were found as pathogens of different arthropods in Austria. Twenty six entomophthoralean species from different insects and one species from mites were identified and 16 of them are recorded as new to Austria. From among 21 species of anamorphic Hypocreales (Ascomycota affecting arthropods in Austria, 13 species so far have not been known from this country. In total 51 species of fungi affecting different arthropods in Poland were recorded, among them 28 species of Entomophthorales and 23 anamorphic Hypocreales (Ascomycota were separated. The most frequent species of the entomopathogenic fungi both in agricultural and afforested areas in Austria were the common and usually worldwide distributed cordycipitaceous anamorphs Beauveria bassiana, Isaria fumosorosea and in areas of this study less numerous I. farinosa. The most frequent pathogens occurring in mite communities on plants and in wood infested by insects were Hirsutella species. Several entomophthoralean species developed epizootics that caused high reduction in host populations of different arthropods in both countries. Especially interesting is the first record of mycoses (up to 60% mortality, caused by Zoophthora spp. on Phyllobius beetles in a mixed forest near Białowieża. During our joint research, we found the first time in Poland and Europe, the presence of the fungus Furia cf. shandongensis on earwigs and Hirsutella entomophila on Ips typographus adults in forest habitats. From the feeding sites of the latter bark beetle and other subcortical species in oak bark (mostly Dryocoetes villosus and D. alni in black alder over a dozen of various Lecanicillium strains - including few of the features not allowing to classify them to any of so far known species – were

  17. Seasonal abundance of soil arthropods in relation to meteorological and edaphic factors in the agroecosystems of Faisalabad, Punjab, Pakistan

    Science.gov (United States)

    Shakir, Muhammad Mussadiq; Ahmed, Sohail

    2015-05-01

    Soil arthropods are an important component of agroecosystems, contributing significantly to their biodiversity and functioning. However, seasonal patterns, population dynamics, and significant roles of these soil arthropods in improvement of soil structures and functions are influenced by many factors. The objective of the current study was to investigate soil arthropod abundance in relation to a blend of meteorological and edaphic factors and to find out the difference in abundance among various crops (sugarcane, cotton, wheat, alfalfa fodder, and citrus orchards). The arthropod sampling was done by pitfall traps and Tullgren extractions on fortnightly intervals. Soil temperature and relative humidity were noted on the field sites while analysis for soil pH, organic matter, and soil moisture contents were done in the laboratory. The rainfall data was obtained from an observatory. Results showed that significant differences were found in soil arthropod abundance across different sampling months and crops. Out of total 13,673 soil arthropods sampled, 38 % belonged to Collembola, followed by 15 % Hymenoptera, 15 % Acarina, 11 % Myriapods, 6 % Coleoptera, 5 % Orthoptera, and 5 % Araneae. Mean abundance per sample was highest in summer months as compared to winter. Overall abundance per sample was significantly different between all crops ( p < 0.05). Cluster analysis revealed four categories of soil arthropods according to abundance, i.e., highly abundant (Collembola, Acarina, Myripoda, Hymenoptera), moderately abundant (Orthoptera, Aranae, Coleoptera), least abundant (Dermaptera, Hemiptera, Diptera), and rare (Blattaria, Isoptera, Diplura, Lepidoptera). Soil temperature and soil organic matter showed significant positive correlation with abundance, while relative humidity was significantly negatively correlated. Soil moisture and soil pH showed no significant correlations while no correlation was found with total rainfall. PCA analysis revealed that soil surface

  18. Vector grammars and PN machines

    Institute of Scientific and Technical Information of China (English)

    蒋昌俊

    1996-01-01

    The concept of vector grammars under the string semantic is introduced.The dass of vector grammars is given,which is similar to the dass of Chomsky grammars.The regular vector grammar is divided further.The strong and weak relation between the vector grammar and scalar grammar is discussed,so the spectrum system graph of scalar and vector grammars is made.The equivalent relation between the regular vector grammar and Petri nets (also called PN machine) is pointed.The hybrid PN machine is introduced,and its language is proved equivalent to the language of the context-free vector grammar.So the perfect relation structure between vector grammars and PN machines is formed.

  19. On Generalized Vector Equilibrium Problems

    Institute of Scientific and Technical Information of China (English)

    An-hua Wan; Jun-yi Fu; Wei-hua Mao

    2006-01-01

    A new generalized vector equilibrium problem involving set-valued mappings and the proper quasi-concavity of set-valued mappings in topological vector spaces are introduced; its existence theorems and the convexity of the solution sets are established.

  20. Effect of some environmental factors on arthropod communities in bat guano

    Directory of Open Access Journals (Sweden)

    Watanasit, S.

    2002-01-01

    Full Text Available Data are presented on the taxonomic composition of arthropod fauna found in bat guano in 6 limestone caves of southern Thailand, collected by Berlese's funnel type trap. There were 2 sampling periods; the first from 29 April to 7 May 1996 and the second from 1 to 4 August 1996. Combined samples of bat guano comprised 4,430 individuals of 32 families of the following : 13 orders (2 classes ; Arachnida and Hexapoda Araneae, Acari, Pseudoscorpiones, Collembola, Blattaria, Hemiptera, Thysanoptera, Psocoptera, Neuroptera, Diptera, Coleoptera, Lepidoptera and Hymenoptera. The relationships between arthropods and physical factors such as cave temperature, relative humi-dity of the cave, moisture in guano, pH of guano, total nitrogen in guano and organic matters in guano were explored. The results showed that the number of individuals of Leptonetidae (P<0.05, Araneae (P<0.05 and Psocoptera (P<0.05 positively correlated with total nitrogen in guano but numbers of Blattellidae (P<0.05 and Blattaria (P<0.05 negatively correlated with total nitrogen in guano. The total numbers of families of arthropods (P<0.05 and the number of individuals of Leptonetidae (P<0.05, Sphaeropsocidae (P<0.05, Liposcelidae (P<0.05, Alleculidae (P<0.01, Chironomidae (P<0.05, Formicidae (P<0.05, Araneae (P<0.05, Psocoptera (P<0.01 and Hymenoptera (P<0.05 positively correlated with organic matters in guano. None of all arthropods correlated with cave temperature, relative humidity of the cave, moisture in guano and pH of guano. Study on the effect of type of bat guano (insectivore or frugivore bat guano and the light factor (light or dark zone on arthropods showed that type of bat guano has an effect on total numbers of families (P<0.05 and the number of individuals of Leptonetidae (P<0.01, Laelapidae (P<0.05, Blattellidae (P<0.05, Sphaeropsocidae (P<0.01, Liposcelidae (P<0.05, Dermestidae (P<0.01, Staphylinidae (P<0.01, Tineidae (P<0.05, Araneae (P<0.01, Blattaria (P<0

  1. Identification of Human Semiochemicals Attractive to the Major Vectors of Onchocerciasis

    Science.gov (United States)

    Young, Ryan M.; Burkett-Cadena, Nathan D.; McGaha, Tommy W.; Rodriguez-Perez, Mario A.; Toé, Laurent D.; Adeleke, Monsuru A.; Sanfo, Moussa; Soungalo, Traore; Katholi, Charles R.; Noblet, Raymond; Fadamiro, Henry; Torres-Estrada, Jose L.; Salinas-Carmona, Mario C.; Baker, Bill; Unnasch, Thomas R.; Cupp, Eddie W.

    2015-01-01

    Background Entomological indicators are considered key metrics to document the interruption of transmission of Onchocerca volvulus, the etiological agent of human onchocerciasis. Human landing collection is the standard employed for collection of the vectors for this parasite. Recent studies reported the development of traps that have the potential for replacing humans for surveillance of O. volvulus in the vector population. However, the key chemical components of human odor that are attractive to vector black flies have not been identified. Methodology/Principal Findings Human sweat compounds were analyzed using GC-MS analysis and compounds common to three individuals identified. These common compounds, with others previously identified as attractive to other hematophagous arthropods were evaluated for their ability to stimulate and attract the major onchocerciasis vectors in Africa (Simulium damnosum sensu lato) and Latin America (Simulium ochraceum s. l.) using electroantennography and a Y tube binary choice assay. Medium chain length carboxylic acids and aldehydes were neurostimulatory for S. damnosum s.l. while S. ochraceum s.l. was stimulated by short chain aliphatic alcohols and aldehydes. Both species were attracted to ammonium bicarbonate and acetophenone. The compounds were shown to be attractive to the relevant vector species in field studies, when incorporated into a formulation that permitted a continuous release of the compound over time and used in concert with previously developed trap platforms. Conclusions/Significance The identification of compounds attractive to the major vectors of O. volvulus will permit the development of optimized traps. Such traps may replace the use of human vector collectors for monitoring the effectiveness of onchocerciasis elimination programs and could find use as a contributing component in an integrated vector control/drug program aimed at eliminating river blindness in Africa. PMID:25569240

  2. Bloch vectors for qudits

    Energy Technology Data Exchange (ETDEWEB)

    Bertlmann, Reinhold A; Krammer, Philipp [Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna (Austria)], E-mail: reinhold.bertlmann@univie.ac.at, E-mail: philipp.krammer@univie.ac.at

    2008-06-13

    We present three different matrix bases that can be used to decompose density matrices of d-dimensional quantum systems, so-called qudits: the generalized Gell-Mann matrix basis, the polarization operator basis and the Weyl operator basis. Such a decomposition can be identified with a vector-the Bloch vector, i.e. a generalization of the well-known qubit case-and is a convenient expression for comparison with measurable quantities and for explicit calculations avoiding the handling of large matrices. We present a new method to decompose density matrices via so-called standard matrices, consider the important case of an isotropic two-qudit state and decompose it according to each basis. In the case of qutrits we show a representation of an entanglement witness in terms of expectation values of spin-1 measurements, which is appropriate for an experimental realization.

  3. Vector mesons in matter

    Indian Academy of Sciences (India)

    Gy Wolf

    2006-04-01

    One consequence of the chiral restoration is the mixing of parity partners. We look for a possible signature of the mixing of vector and axial vector mesons in heavy-ion collisions. We suggest an experimental method for its observation. The dynamical evolution of the heavy-ion collision is described by a transport equation of QMD-type evolving nucleons, * and resonances, ’s and $\\sum$ baryons, and furthermore, ’s, ’s ’s ’s ’s and kaons with their isospin degrees of freedom. The input cross-sections and resonance parameters of the model are fitted to the available nucleon–nucleon and pion–nucleon cross-sections.

  4. Future challenges for parasitology: vector control and 'One health' in Europe: the veterinary medicinal view on CVBDs such as tick borreliosis, rickettsiosis and canine leishmaniosis.

    Science.gov (United States)

    Mencke, Norbert

    2013-08-01

    The medical as well as the veterinary importance of parasitic arthropods or ectoparasites in general terms, is characterized by the primary or secondary impact on the health of humans and companion animals alike. The parasitic arthropods addressed here are those ectoparasites belong to the class of insects, such as fleas and sand flies, or the subclass of acarids, such as ticks. These parasitic arthropods interact intensively with their hosts by blood feeding. Fleas, sand flies and ticks hold the vector capacity to transmit pathogens such as virus, bacteria or protozoa to cats, dogs and humans. The diseases caused by these pathogens are summarized under the terms canine vector-borne diseases (CVBD), feline vector-borne diseases (FVBD) or metazoonoses. In small animal practice, it is important to understand that the transmitted pathogen may either lead to a disease with clinical signs, or more often to asymptomatic, clinically healthy, or silent infections. Blocking of the vector-host interactions, the blood feeding and subsequently the transmission of pathogens during blood feeding is a key element of CVBD control. The focus of this review is on the current knowledge of the epidemiology of parasitic vectors and three important CVBDs they transmit; rickettsiosis, tick borreliosis and canine leishmaniosis from a European perspective, and how veterinary medicine may contribute to the challenges of CVBDs and their control. Prevention of CVBDs is fundamentally based on ectoparasite control. Ectoparasite management in cats and dogs is important not only for the health and well-being of the individual companion animal but for public health in general and is therefore a perfect example of the 'One health' approach.

  5. Engineering influenza viral vectors

    OpenAIRE

    Li, Junwei; Arévalo, Maria T; Zeng, Mingtao

    2013-01-01

    The influenza virus is a respiratory pathogen with a negative-sense, segmented RNA genome. Construction of recombinant influenza viruses in the laboratory was reported starting in the 1980s. Within a short period of time, pioneer researchers had devised methods that made it possible to construct influenza viral vectors from cDNA plasmid systems. Herein, we discuss the evolution of influenza virus reverse genetics, from helper virus-dependent systems, to helper virus-independent 17-plasmid sys...

  6. Helices and vector bundles

    CERN Document Server

    Rudakov, A N

    1990-01-01

    This volume is devoted to the use of helices as a method for studying exceptional vector bundles, an important and natural concept in algebraic geometry. The work arises out of a series of seminars organised in Moscow by A. N. Rudakov. The first article sets up the general machinery, and later ones explore its use in various contexts. As to be expected, the approach is concrete; the theory is considered for quadrics, ruled surfaces, K3 surfaces and P3(C).

  7. Japanese Encephalitis Vectors

    OpenAIRE

    Wada, Yoshito

    1995-01-01

    On the ecological basis of vector mosquitoes of Japanese encephalitis, measures of their control were examined from viewpoint of their practicability. It was concluded that chemical control is not of practical value, biological control is of limited effectiveness, and environmental control by source reduction is impossible. Instead, it was recommended to improve human living style so as to reduce the frequency of man/mosquito contact.

  8. Interpolation of Vector Measures

    Institute of Scientific and Technical Information of China (English)

    Ricardo del CAMPO; Antonio FERN(A)NDEZ; Fernando MAYORAL; Francisco NARANJO; Enrique A. S(A)NCHEZ-P(E)REZ

    2011-01-01

    Let (Ω, ∑) be a measurable space and m0: ∑→ X0 and m1: ∑ -→ X1 be positive vector measures with values in the Banach K(o)the function spaces X0 and X1. If 0 < α < 1, we define a X10-αXα1 and we analyze the space of integrable functions with respect to measure [m0, m1]α in order to prove suitable extensions of the classical Stein-Weiss formulas that hold for the complex interpolation of Lp-spaces.Since each p-convex order continuous K(o)the function space with weak order unit can be represented as a space of p-integrable functions with respect to a vector measure, we provide in this way a technique to obtain representations of the corresponding complex interpolation spaces. As applications, we provide a Riesz-Thorin theorem for spaces of p-integrable functions with respect to vector measures and a formula for representing the interpolation of the injective tensor product of such spaces.

  9. Factors affecting the abundance of leaf-litter arthropods in unburned and thrice-burned seasonally-dry Amazonian forests.

    Directory of Open Access Journals (Sweden)

    Juliana M Silveira

    Full Text Available Fire is frequently used as a land management tool for cattle ranching and annual crops in the Amazon. However, these maintenance fires often escape into surrounding forests, with potentially severe impacts for forest biodiversity. We examined the effect of experimental fires on leaf-litter arthropod abundance in a seasonally-dry forest in the Brazilian Amazon. The study plots (50 ha each included a thrice-burned forest and an unburned control forest. Pitfall-trap samples were collected at 160 randomly selected points in both plots, with sampling stratified across four intra-annual replicates across the dry and wet seasons, corresponding to 6, 8, 10 and 12 months after the most recent fire. Arthropods were identified to the level of order (separating Formicidae. In order to better understand the processes that determine arthropod abundance in thrice-burned forests, we measured canopy openness, understory density and litter depth. All arthropod taxa were significantly affected by fire and season. In addition, the interactions between burn treatment and season were highly significant for all taxa but Isoptera. The burned plot was characterized by a more open canopy, lower understory density and shallower litter depth. Hierarchical partitioning revealed that canopy openness was the most important factor explaining arthropod order abundances in the thrice-burned plot, whereas all three environmental variables were significant in the unburned control plot. These results reveal the marked impact of recurrent wildfires and seasonality on litter arthropods in this transitional forest, and demonstrate the overwhelming importance of canopy-openness in driving post-fire arthropod abundance.

  10. Factors affecting the abundance of leaf-litter arthropods in unburned and thrice-burned seasonally-dry Amazonian forests.

    Science.gov (United States)

    Silveira, Juliana M; Barlow, Jos; Louzada, Julio; Moutinho, Paulo

    2010-01-01

    Fire is frequently used as a land management tool for cattle ranching and annual crops in the Amazon. However, these maintenance fires often escape into surrounding forests, with potentially severe impacts for forest biodiversity. We examined the effect of experimental fires on leaf-litter arthropod abundance in a seasonally-dry forest in the Brazilian Amazon. The study plots (50 ha each) included a thrice-burned forest and an unburned control forest. Pitfall-trap samples were collected at 160 randomly selected points in both plots, with sampling stratified across four intra-annual replicates across the dry and wet seasons, corresponding to 6, 8, 10 and 12 months after the most recent fire. Arthropods were identified to the level of order (separating Formicidae). In order to better understand the processes that determine arthropod abundance in thrice-burned forests, we measured canopy openness, understory density and litter depth. All arthropod taxa were significantly affected by fire and season. In addition, the interactions between burn treatment and season were highly significant for all taxa but Isoptera. The burned plot was characterized by a more open canopy, lower understory density and shallower litter depth. Hierarchical partitioning revealed that canopy openness was the most important factor explaining arthropod order abundances in the thrice-burned plot, whereas all three environmental variables were significant in the unburned control plot. These results reveal the marked impact of recurrent wildfires and seasonality on litter arthropods in this transitional forest, and demonstrate the overwhelming importance of canopy-openness in driving post-fire arthropod abundance. PMID:20877720

  11. Scalar - vector soliton fiber lasers

    CERN Document Server

    Wu, Zhichao; Li, Lei; Luo, Yiyang; Tang, Dingyuan; Shen, Deyuan; Tang, Ming; Fu, Songnian; Zhao, Luming

    2016-01-01

    Rapid progress in passively mode-locked fiber lasers is currently driven by the recent discovery of vector feature of mode-locking pulses, namely, the group velocity-locked vector solitons, the phase locked vector solitons, and the high-order vector solitons. Those vector solitons are fundamentally different from the previously known scalar solitons. Here, we report a fiber laser where the mode-locked pulse evolves as a vector soliton in the strong birefringent segment and is transformed into a regular scalar soliton after the polarizer within the laser cavity. The existence of solutions in a polarization-dependent cavity comprising a periodic combination of two distinct nonlinear waves is novel and likely to be applicable to various other nonlinear systems. For very large local birefringence, our laser approaches the working regime of vector soliton lasers, while it approaches scalar soliton fiber lasers under the conditions of very small birefringence.

  12. The influence of weather conditions on the activity of high-arctic arthropods inferred from long-term observations

    Directory of Open Access Journals (Sweden)

    Høye Toke T

    2008-05-01

    Full Text Available Abstract Background Climate change is particularly pronounced in the High Arctic and a better understanding of the repercussions on ecological processes like herbivory, predation and pollination is needed. Arthropods play an important role in the high-arctic ecosystem and this role is determined by their density and activity. However, density and activity may be sensitive to separate components of climate. Earlier emergence due to advanced timing of snowmelt following climate change may expose adult arthropods to unchanged temperatures but higher levels of radiation. The capture rate of arthropods in passive open traps like pitfall trap integrates density and activity and, therefore, serves as a proxy of the magnitude of such arthropod-related ecological processes. We used arthropod pitfall trapping data and weather data from 10 seasons in high-arctic Greenland to identify climatic effects on the activity pattern of nine arthropod taxa. Results We were able to statistically separate the variation in capture rates into a non-linear component of capture date (density and a linear component of weather (activity. The non-linear proxy of density always accounted for more of the variation than the linear component of weather. After accounting for the seasonal phenological development, the most important weather variable influencing the capture rate of flying arthropods was temperature, while surface-dwelling species were principally influenced by solar radiation. Conclusion Consistent with previous findings, air temperature best explained variation in the activity level of flying insects. An advancement of the phenology in this group due to earlier snowmelt will make individuals appear earlier in the season, but parallel temperature increases could mean that individuals are exposed to similar temperatures. Hence, the effect of climatic changes on the activity pattern in this group may be unchanged. In contrast, we found that solar radiation is a

  13. Secondary succession of arthropods and plants in the Arizona Sonoran Desert in response to transmission line construction

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, C.D.; Beley, J.R.; Ditsworth, T.M.; Butt, S.M.

    1983-03-01

    At a site about 16 km south of Black Canyon City, Arizona, density of arthropods on an undisturbed plot after an access road was built for powerline construction was much greater than on a disturbed plot. Mites, springtails, leafhoppers, scale insects, ants and thrips were signficantly reduced on the disturbed area. Our results indicate that restoration of numbers of arthropods on the disturbed area is dependent on the total plant cover on the plot, apparently regardless of the composition of the plant species involved. It is obvious in this area that the plant communities will remain dissimilar, with the pioneering herbaceous plants on the disturbed plot dominating. Cosntruction of a powerline apparently has had little impact on the structure of the arthropod community on the disturbed area, as proportions of three trophic categories of arthropods have not been radically altered. The results of this study, when compared to other studies in the Sonoran Desert and in desert grasslands disturbed by powerline construction, indicate that lengthy secondary succession does occur in the Sonoran Desert. Early arthropod invaders were found to be mainly herbivores, with few parasites or predators, and an equilibrium was eventually reached between colonizers and space requirements.

  14. Breeding Westland petrels as providers of detrital carbon and nitrogen for soil arthropods : a stable isotope study

    International Nuclear Information System (INIS)

    Seabirds deposit large quantities of marine detritus on land, but little is known of the soil arthropods processing this material. Burrow-nesting seabirds concentrate their activities within their burrows, so we tested the hypothesis that burrow arthropod fauna is more marine-like in its isotopic enrichment (13C/12C, 15N/14N); expressed as δ13C and δ15N) than the arthropods on the adjacent forest floor. Results from a Westland petrel (Procellaria westlandica) colony on the South Island of New Zealand did not support the hypothesis. Instead, δ15N was universally marine (13-22 per mil). While δ13C separated into two clusters, the distribution was not according to arthropod provenance. Most taxa had a terrestrial δ13C; only two taxa (a leiodid beetle and the mesostigmatic mite Ayersacarus woodi) incorporated marine C. The leiodid beetle occurs both in burrows and on the forest floor; beetles from both habitats had a marine δ13C. Ayersacarus woodi is found only in burrows. We conclude that, in this system, marine and terrestrial detrital C is processed separately, and that marine detrital C enters the terrestrial ecosystem through a very few arthropod taxa. (author). 33 refs., 1 fig.

  15. Richness, diversity, and similarity of arthropod prey consumed by a community of Hawaiian forest birds.

    Science.gov (United States)

    Banko, Paul C.; Peck, Robert W.; Brinck, Kevin W.; Leonard, David L.

    2015-01-01

    We evaluated the diet richness, diversity, and similarity of a community of seven endemic and two introduced passerine birds by analyzing the composition of arthropod prey in fecal samples collected during 1994–1998 at Hakalau Forest National Wildlife Refuge, Hawai‘i Island. Most prey fragments were identified to order, but we also distinguished among morpho-species of Lepidoptera based on the shape of larval (caterpillar) mandibles for higher resolution of this important prey type. Diets were compared among feeding specialists, generalists, and “intermediate” species and among introduced and three endangered Hawaiian honeycreeper (Fringillidae) species. Lepidoptera (moths), especially the larval (caterpillar) stage, comprised the greatest proportion of prey in samples of all bird species except for the introduced Japanese white-eye (Zosterops japonicus; JAWE). Araneae (spiders) was the most abundant order in JAWE samples and the second most abundant order for most other species. The two specialist honeycreepers ranked lowest in the richness and diversity of arthropod orders, but only the ‘akiapōlā‘au (Hemignathus munroi, AKIP) was significantly lower than the three generalist or intermediate honeycreeper species. The diversity of arthropod orders was significantly lower for the three endangered honeycreeper species compared to the two introduced species. No significant differences were observed among the five honeycreepers with respect to the arthropod orders they consumed. The use of arthropod orders taken by endangered honeycreepers and introduced species was significantly different in all paired comparisons except for JAWE and ‘ākepa (Loxops coccineus; AKEP). In terms of richness and diversity of caterpillar morpho-species in the diet, only the specialist, AKEP, was significantly lower than all three generalist and intermediate species. Both AKEP and AKIP consumed a significantly different diet of caterpillar morpho-species compared to at least

  16. Relativistic Rotating Vector Model

    CERN Document Server

    Lyutikov, Maxim

    2016-01-01

    The direction of polarization produced by a moving source rotates with the respect to the rest frame. We show that this effect, induced by pulsar rotation, leads to an important correction to polarization swings within the framework of rotating vector model (RVM); this effect has been missed by previous works. We construct relativistic RVM taking into account finite heights of the emission region that lead to aberration, time-of-travel effects and relativistic rotation of polarization. Polarizations swings at different frequencies can be used, within the assumption of the radius-to-frequency mapping, to infer emission radii and geometry of pulsars.

  17. Diversity and distribution of arthropods in native forests of the Azores archipelago

    Directory of Open Access Journals (Sweden)

    Borges, P.A.V.

    2008-01-01

    Full Text Available Since 1999, our knowledge of arthropods in native forests of the Azores has improved greatly. Under the BALA project (Biodiversity of Arthropods of Laurisilva of the Azores, an extensive standardised sampling protocol was employed in most of the native forest cover of the Archipelago. Additionally, in 2003 and 2004, more intensive sampling was carried out in several fragments, resulting in nearly a doubling of the number of samples collected. A total of 6,770 samples from 100 sites distributed amongst 18 fragments of seven islands have been collected, resulting in almost 140,000 specimens having been caught. Overall, 452 arthropod species belonging to Araneae, Opilionida, Pseudoscorpionida, Myriapoda and Insecta (excluding Diptera and Hymenoptera were recorded. Altogether, Coleoptera, Hemiptera, Araneae and Lepidoptera comprised the major proportion of the total diversity (84% and total abundance (78% found. Endemic species comprised almost half of the individuals sampled. Most of the taxonomic, colonization, and trophic groups analysed showed a significantly left unimodal distribution of species occurrences, with almost all islands, fragments or sites having exclusive species. Araneae was the only group to show a strong bimodal distribution. Only a third of the species was common to both the canopy and soil, the remaining being equally exclusive to each stratum. Canopy and soil strata showed a strongly distinct species composition, the composition being more similar within the same stratum regardless of the location, than within samples from both strata at the same location. Possible reasons for these findings are explored. The procedures applied in the sampling protocol are also discussed.

  18. The origin of herbivory on land: Initial patterns of plant tissue consumption by arthropods

    Institute of Scientific and Technical Information of China (English)

    CONRAD LABANDEIRA

    2007-01-01

    The early fossil record of terrestrial arthropod herbivory consists of two pulses.The first pulse was concentrated during the latest Silurian to Early Devonian (417 to 403 Ma),and consists of the earliest evidence for consumption of sporangia and stems (and limited fungivore borings). Herbivorization of most of these tissues was rapid, representing 0 to 20 million-year (m.y.) lags from the earliest occurrences of these organs in the fossil record to their initial consumption (Phase 1). For approximately the next 75 m.y., there was a second,more histologically varied origination and expansion of roots, leaves, wood and seeds,whose earliest evidence for herbivorization occurred from the Middle-Late Mississippian boundary to the Middle Pennsylvanian (327 to 309 Ma). The appearance of this second herbivory pulse during the later Paleozoic (Phase 2) is accompanied by major lags of 98 to 54 m.y. between times of appearance of each of the four organ and tissue types and their subsequent herbivory. Both pulses provide a context for three emerging questions. First is an explanation for the contrast between the near instantaneous consumption of plant tissues during Phase 1, versus the exceptionally long lags between the earliest occurrences of plant tissues and their subsequent herbivorization during Phase 2. Second is the identity of arthropod herbivores for both phases. Third is the cause behind the overwhelming targeting of seed-fern plant hosts during Phase 2. Regardless of the answers to these questions, the trace fossil record of plant-arthropod associations provides primary ecological data that remain unaddressed by the body-fossil record alone.

  19. Soil arthropod fauna from natural ecosites and reclaimed oil sands soils in northern Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Battigelli, J.P.; Leskiw, L.A. [Paragon Soil and Environmental Consulting Inc., Edmonton, AB (Canada)

    2006-07-01

    An understanding of soil invertebrates may facilitate current reclamation activities in the oil sands region of Alberta. This paper presented the results of a study investigating the density, diversity, and structure of soil arthropod assemblages in natural habitats and reclaimed sites. The purpose of the study was to establish a baseline inventory of soil arthropod assemblages in order to enable long-term monitoring of soil arthropod recolonization in disturbed sites. Nine natural ecosites were sampled for the study, including peat mix over secondary material over tailing sand; direct placement over tailing sand; peat mix over secondary over overburden; direct placement over overburden; peat mix over tailing sand; and peat mix over overburden. Samples were collected from previously established long-term soil and vegetation treatment plots in both natural ecosites and reclaimed soil sites located near Fort McMurray, Alberta. Results showed that densities of mesofauna were significantly higher in samples collected from natural ecosites. Acari and Collembola represented approximately 97 to 98 per cent of the fauna collected. It was also noted that the overall structure of the soil mesofauna community differed between natural soils and reclaimed soils. A significant reduction in the abundance of oribatid mites was observed in soils that had been reclaimed for over 34 years. Changes in the soil mesofauna community structure suggested that reclaimed soils continue to represent disturbed ecosites, as was indicated by higher proportions of prostigmatid mites and some collembolan families. Differences in community structure may influence soil ecosystem functions, including decomposition rates; nutrient recycling; soil structure; and fungal and bacterial biomass. It was concluded that further research is needed to examine oribatid mites and collembolan species diversity and community structure in reclaimed soils. 18 refs., 6 figs.

  20. ASGARD: an open-access database of annotated transcriptomes for emerging model arthropod species.

    Science.gov (United States)

    Zeng, Victor; Extavour, Cassandra G

    2012-01-01

    The increased throughput and decreased cost of next-generation sequencing (NGS) have shifted the bottleneck genomic research from sequencing to annotation, analysis and accessibility. This is particularly challenging for research communities working on organisms that lack the basic infrastructure of a sequenced genome, or an efficient way to utilize whatever sequence data may be available. Here we present a new database, the Assembled Searchable Giant Arthropod Read Database (ASGARD). This database is a repository and search engine for transcriptomic data from arthropods that are of high interest to multiple research communities but currently lack sequenced genomes. We demonstrate the functionality and utility of ASGARD using de novo assembled transcriptomes from the milkweed bug Oncopeltus fasciatus, the cricket Gryllus bimaculatus and the amphipod crustacean Parhyale hawaiensis. We have annotated these transcriptomes to assign putative orthology, coding region determination, protein domain identification and Gene Ontology (GO) term annotation to all possible assembly products. ASGARD allows users to search all assemblies by orthology annotation, GO term annotation or Basic Local Alignment Search Tool. User-friendly features of ASGARD include search term auto-completion suggestions based on database content, the ability to download assembly product sequences in FASTA format, direct links to NCBI data for predicted orthologs and graphical representation of the location of protein domains and matches to similar sequences from the NCBI non-redundant database. ASGARD will be a useful repository for transcriptome data from future NGS studies on these and other emerging model arthropods, regardless of sequencing platform, assembly or annotation status. This database thus provides easy, one-stop access to multi-species annotated transcriptome information. We anticipate that this database will be useful for members of multiple research communities, including developmental

  1. Some topological properties of arthropod food webs in paddy fields of South China

    Directory of Open Access Journals (Sweden)

    LiQin Jiang

    2015-09-01

    Full Text Available To explore the topological properties of paddy arthropod food webs is of significance for understanding natural equilibrium of rice pests. In present study, we used Pajek software to analyze the topological properties of four full arthropod food webs in South China. The results showed that predators were significantly abundant than preys, and the proportion of predators to preys (3.07 was significantly higher than previously reported by Cohen in 1977 (1.33. In the food webs, the number of top species was the largest, accounted for about 50% of the total. The number of intermediate-intermediate links was far greater than the other three links. The average degree of paddy arthropod food webs is 6.0, 6.04, 5.74 and 7.75, respectively. Average degree and link density did not change significantly with the change of the number of species, but the connectance reduced significantly. In the paddy ecosystems, the increase of species diversity does not lead to an increase proportionally to the links among species. The link density and connectance of food webs of early season rice field were less than that from late season rice field. Cycles of all food webs cycles were 0. The maximum chain length of the basal species was 3, and the largest chain length of the top species was typically 2 or 3. Neutral insects were found to play a very important role in the paddy ecosystem. Nilaparvata lugens and Sogatella furcifera were found to be the dominant species of rice pests. Pardosa pseudoannulata, Tetragnatha maxillosa, Pirata subparaticus, Arctosa stigmosa and Clubiona corrugate were identified as the important predatory species that may effectively control the pest population. The keystone species calculated from keystone index and network analysis are analogous, indicating either keystone index or network analysis can be used in the analysis of keystone species.

  2. Biodiversity and resilience of arthropod communities after fire disturbance in temperate forests.

    Science.gov (United States)

    Moretti, Marco; Duelli, Peter; Obrist, Martin K

    2006-08-01

    Changes in ecosystem functions following disturbances are of central concern in ecology and a challenge for ecologists is to understand the factors that affect the resilience of community structures and ecosystem functions. In many forest ecosystems, one such important natural disturbance is fire. The aim of this study was to understand the variation of resilience in six functional groups of invertebrates in response to different fire frequencies in southern Switzerland. We measured resilience by analysing arthropod species composition, abundance and diversity in plots where the elapsed time after single or repeated fires, as determined by dendrochronology, varied. We compared data from these plots with data from plots that had not burned recently and defined high resilience as the rapid recovery of the species composition to that prior to fire. Pooling all functional groups showed that they were more resilient to single fires than to repeated events, recovering 6-14 years after a single fire, but only 17-24 years after the last of several fires. Flying zoophagous and phytophagous arthropods were the most resilient groups. Pollinophagous and epigaeic zoophagous species showed intermediate resilience, while ground-litter saprophagous and saproxylophagous arthropods clearly displayed the lowest resilience to fire. Their species composition 17-24 years post-burn still differed markedly from that of the unburned control plots. Depending on the fire history of a forest plot, we found significant differences in the dominance hierarchy among invertebrate species. Any attempt to imitate natural disturbances, such as fire, through forest management must take into account the recovery times of biodiversity, including functional group composition, to ensure the conservation of multiple taxa and ecosystem functions in a sustainable manner. PMID:16804704

  3. Biodiversity and resilience of arthropod communities after fire disturbance in temperate forests.

    Science.gov (United States)

    Moretti, Marco; Duelli, Peter; Obrist, Martin K

    2006-08-01

    Changes in ecosystem functions following disturbances are of central concern in ecology and a challenge for ecologists is to understand the factors that affect the resilience of community structures and ecosystem functions. In many forest ecosystems, one such important natural disturbance is fire. The aim of this study was to understand the variation of resilience in six functional groups of invertebrates in response to different fire frequencies in southern Switzerland. We measured resilience by analysing arthropod species composition, abundance and diversity in plots where the elapsed time after single or repeated fires, as determined by dendrochronology, varied. We compared data from these plots with data from plots that had not burned recently and defined high resilience as the rapid recovery of the species composition to that prior to fire. Pooling all functional groups showed that they were more resilient to single fires than to repeated events, recovering 6-14 years after a single fire, but only 17-24 years after the last of several fires. Flying zoophagous and phytophagous arthropods were the most resilient groups. Pollinophagous and epigaeic zoophagous species showed intermediate resilience, while ground-litter saprophagous and saproxylophagous arthropods clearly displayed the lowest resilience to fire. Their species composition 17-24 years post-burn still differed markedly from that of the unburned control plots. Depending on the fire history of a forest plot, we found significant differences in the dominance hierarchy among invertebrate species. Any attempt to imitate natural disturbances, such as fire, through forest management must take into account the recovery times of biodiversity, including functional group composition, to ensure the conservation of multiple taxa and ecosystem functions in a sustainable manner.

  4. Seasonal occurrence of key arthropod pests and associated natural enemies in Alabama Satsuma citrus.

    Science.gov (United States)

    Fadamiro, Henry Y; Xiao, Yingfang; Hargroder, Terry; Nesbitt, Monte; Umeh, Vincent; Childers, Carl C

    2008-04-01

    Six Alabama Satsuma mandarin orchards (four conventionally sprayed and two unsprayed) were surveyed during 2005 and 2006 to determine the population dynamics of arthropod pests and their natural enemies. Twenty-eight arthropod pest species were encountered; the major foliage pests were citrus whitefly, Dialeurodes citri (Ashmead); purple scale, Lepidosaphes beckii (Newman); Glover scale, L. gloveri (Packard); and citrus red mite, Panonychus citri (McGregor). Two distinct population peaks were recorded for citrus whitefly at most locations. The most important direct sources of citrus whitefly mortality were parasitism by Encarsia lahorensis (Howard) and infection by the pathogenic fungus, Aschersonia aleyrodis Webber. In general, all stages of both scale insects (purple scale and Glover scale) were present in the orchards year-round, indicative of overlapping generations; however, the highest densities were recorded during the early season. Citrus whitefly, purple scale, and Glover scale were more abundant on leaves collected from the interior of the tree canopy than in the exterior canopy. Citrus red mite densities were highest in the spring, with populations declining at the start of the summer, and were more abundant in the exterior canopy than in the interior canopy. The most important natural enemies of citrus red mite were predatory mites belonging to several families, of which Typhlodromalus peregrinus Muma (Phytoseiidae) was the predominant species. Major differences were recorded in the relative abundance of different arthropod pest species in the orchards: citrus whitefly, purple scale, and Glover scale predominated in the unsprayed orchards, whereas citrus red mite infestations were more severe in the sprayed orchards. The results are discussed in relation to the possible effect of orchard management practices on abundance of the major pests. PMID:18419929

  5. Discontinuous gas exchange in a tracheate arthropod, the pseudoscorpion Garypus californicus: Occurrence, characteristics and temperature dependence.

    OpenAIRE

    Lighton, John R. B.; Barbara Joos

    2002-01-01

    The discontinuous gas exchange cycle of the pseudoscorpion Garypus californicus, mean mass 5.9 mg, is rudimentary and is characterized by bursts of CO2 at frequencies ranging from 3.6 mHz at 15 °C to 13.3 mHz at 35 °C. The mean volume of CO2 emitted per burst is 3.6 µl g-1 at 25 °C, about a tenth of the amount emitted by tracheate arthropods with a well developed discontinuous gas exchange cycle. Interburst CO2 emission is high and increases with temperature, reaching near 45% of total CO2 pr...

  6. High spatial variation in terrestrial arthropod species diversity and composition near the Greenland ice cap

    DEFF Research Database (Denmark)

    Hansen, Rikke Reisner; Hansen, Oskar Liset Pryds; Bowden, Joseph James;

    2016-01-01

    . The empirical basis for this assumption, however, is weak. We examine the degree of spatial variation in species diversity and assemblage structure among five habitat types at two sites of similar abiotic conditions and plant species composition in southwest Greenland, using standardized field collection...... conclude that Arctic arthropod species assemblages vary substantially over short distances due to local soil characteristics, while regional variation in the species pool is likely influenced by geographic barriers, i.e., inland ice sheet, glaciers, mountains and large water bodies. In order to predict...

  7. Effect of commercially available plant-derived essential oil products on arthropod pests.

    Science.gov (United States)

    Cloyd, Raymond A; Galle, Cindy L; Keith, Stephen R; Kalscheur, Nanette A; Kemp, Kenneth E

    2009-08-01

    Plant-derived essential oil products, in general, are considered minimum-risk pesticides and are exempt from Environmental Protection Agency registration under section 25(b) of the Federal Insecticide Fungicide and Rodenticide Act. However, many of the plant-derived essential products available to consumers (homeowners) have not been judiciously evaluated for both efficacy and plant safety. In fact, numerous plant-derived essential oil products labeled for control of arthropod pests have not been subject to rigorous evaluation, and there is minimal scientific information or supporting data associated with efficacy against arthropod pests. We conducted a series of greenhouse experiments to determine the efficacy and phytotoxicity of an array of plant-derived essential oil products available to consumers on arthropod pests including the citrus mealybug, Planococcus citri (Risso); western flower thrips, Frankliniella occidentalis (Pergande); twospotted spider mite, Tetranychus urticae Koch; sweetpotato whitefly B-biotype, Bemisia tabaci (Gennadius); and green peach aphid, Myzus persicae (Sulzer). Although the products Flower Pharm (cottonseed, cinnamon, and rosemary oil) and Indoor Pharm (soybean, rosemary, and lavender oil) provided > 90% mortality of citrus mealybug, they were also the most phytotoxic to the coleus, Solenostemon scutellarioides (L.) Codd, plants. Both GC-Mite (cottonseed, clove, and garlic oil) and Bugzyme (citric acid) were most effective against the twospotted spider mite (> or = 90% mortality). However, SMC (canola, coriander oil, and triethanolamine), neem (clarified hydrophobic extract of neem oil), and Bug Assassin (eugenol, sodium lauryl sulfate, peppermint, and citronella oil) provided > 80% mortality. Monterey Garden Insect Spray, which contained 0.5% spinosad, was most effective against western flower thrips with 100% mortality. All the other products evaluated failed to provide sufficient control of western flower thrips with or = 4.5 of

  8. Comparative genomic analysis of Drosophila melanogaster and vector mosquito developmental genes.

    Directory of Open Access Journals (Sweden)

    Susanta K Behura

    Full Text Available Genome sequencing projects have presented the opportunity for analysis of developmental genes in three vector mosquito species: Aedes aegypti, Culex quinquefasciatus, and Anopheles gambiae. A comparative genomic analysis of developmental genes in Drosophila melanogaster and these three important vectors of human disease was performed in this investigation. While the study was comprehensive, special emphasis centered on genes that 1 are components of developmental signaling pathways, 2 regulate fundamental developmental processes, 3 are critical for the development of tissues of vector importance, 4 function in developmental processes known to have diverged within insects, and 5 encode microRNAs (miRNAs that regulate developmental transcripts in Drosophila. While most fruit fly developmental genes are conserved in the three vector mosquito species, several genes known to be critical for Drosophila development were not identified in one or more mosquito genomes. In other cases, mosquito lineage-specific gene gains with respect to D. melanogaster were noted. Sequence analyses also revealed that numerous repetitive sequences are a common structural feature of Drosophila and mosquito developmental genes. Finally, analysis of predicted miRNA binding sites in fruit fly and mosquito developmental genes suggests that the repertoire of developmental genes targeted by miRNAs is species-specific. The results of this study provide insight into the evolution of developmental genes and processes in dipterans and other arthropods, serve as a resource for those pursuing analysis of mosquito development, and will promote the design and refinement of functional analysis experiments.

  9. Vectors as Epidemiological Sentinels: Patterns of Within-Tick Borrelia burgdorferi Diversity.

    Science.gov (United States)

    Walter, Katharine S; Carpi, Giovanna; Evans, Benjamin R; Caccone, Adalgisa; Diuk-Wasser, Maria A

    2016-07-01

    Hosts including humans, other vertebrates, and arthropods, are frequently infected with heterogeneous populations of pathogens. Within-host pathogen diversity has major implications for human health, epidemiology, and pathogen evolution. However, pathogen diversity within-hosts is difficult to characterize and little is known about the levels and sources of within-host diversity maintained in natural populations of disease vectors. Here, we examine genomic variation of the Lyme disease bacteria, Borrelia burgdorferi (Bb), in 98 individual field-collected tick vectors as a model for study of within-host processes. Deep population sequencing reveals extensive and previously undocumented levels of Bb variation: the majority (~70%) of ticks harbor mixed strain infections, which we define as levels Bb diversity pre-existing in a diverse inoculum. Within-tick diversity is thus a sample of the variation present within vertebrate hosts. Within individual ticks, we detect signatures of positive selection. Genes most commonly under positive selection across ticks include those involved in dissemination in vertebrate hosts and evasion of the vertebrate immune complement. By focusing on tick-borne Bb, we show that vectors can serve as epidemiological and evolutionary sentinels: within-vector pathogen diversity can be a useful and unbiased way to survey circulating pathogen diversity and identify evolutionary processes occurring in natural transmission cycles. PMID:27414806

  10. Extended vector-tensor theories

    CERN Document Server

    Kimura, Rampei; Yoshida, Daisuke

    2016-01-01

    Recently, several extensions of massive vector theory in curved space-time have been proposed in many literatures. In this paper, we consider the most general vector-tensor theories that contain up to two derivatives with respect to metric and vector field. By imposing a degeneracy condition of the Lagrangian in the context of ADM decomposition of space-time to eliminate an unwanted mode, we construct a new class of massive vector theories where five degrees of freedom can propagate, corresponding to three for massive vector modes and two for massless tensor modes. We find that the generalized Proca and the beyond generalized Proca theories up to the quartic Lagrangian, which should be included in this formulation, are degenerate theories even in curved space-time. Finally, introducing new metric and vector field transformations, we investigate the properties of thus obtained theories under such transformations.

  11. Semitopological Vector Spaces and Hyperseminorms

    Directory of Open Access Journals (Sweden)

    Mark Burgin

    2013-11-01

    Full Text Available In this paper, we introduce and study semitopological vector spaces. The goal is to provide an efficient base for developing the theory of extrafunction spaces in an abstract setting of algebraic systems and topological spaces. Semitopological vector spaces are more general than conventional topological vector spaces, which proved to be very useful for solving many problems in functional analysis. To study semitopological vector spaces, hypermetrics and hyperpseudometrics are introduced and it is demonstrated that hyperseminorms, studied in previous works of the author, induce hyperpseudometrics, while hypernorms induce hypermetrics. Sufficient and necessary conditions for a hyperpseudometric (hypermetric to be induced by a hyperseminorm (hypernorm are found. We also show that semitopological vector spaces are closely related to systems of hyperseminorms. Then defining boundedness and continuity relative to associated systems of hyperseminorms, we study relations between relative boundedness and relative continuity for mappings of vector spaces with systems of hyperseminorms and systems of hypernorms.

  12. The First Myriapod Genome Sequence Reveals Conservative Arthropod Gene Content and Genome Organisation in the Centipede Strigamia maritima

    Science.gov (United States)

    Chipman, Ariel D.; Ferrier, David E. K.; Brena, Carlo; Qu, Jiaxin; Hughes, Daniel S. T.; Schröder, Reinhard; Torres-Oliva, Montserrat; Znassi, Nadia; Jiang, Huaiyang; Almeida, Francisca C.; Alonso, Claudio R.; Apostolou, Zivkos; Aqrawi, Peshtewani; Arthur, Wallace; Barna, Jennifer C. J.; Blankenburg, Kerstin P.; Brites, Daniela; Capella-Gutiérrez, Salvador; Coyle, Marcus; Dearden, Peter K.; Du Pasquier, Louis; Duncan, Elizabeth J.; Ebert, Dieter; Eibner, Cornelius; Erikson, Galina; Evans, Peter D.; Extavour, Cassandra G.; Francisco, Liezl; Gabaldón, Toni; Gillis, William J.; Goodwin-Horn, Elizabeth A.; Green, Jack E.; Griffiths-Jones, Sam; Grimmelikhuijzen, Cornelis J. P.; Gubbala, Sai; Guigó, Roderic; Han, Yi; Hauser, Frank; Havlak, Paul; Hayden, Luke; Helbing, Sophie; Holder, Michael; Hui, Jerome H. L.; Hunn, Julia P.; Hunnekuhl, Vera S.; Jackson, LaRonda; Javaid, Mehwish; Jhangiani, Shalini N.; Jiggins, Francis M.; Jones, Tamsin E.; Kaiser, Tobias S.; Kalra, Divya; Kenny, Nathan J.; Korchina, Viktoriya; Kovar, Christie L.; Kraus, F. Bernhard; Lapraz, François; Lee, Sandra L.; Lv, Jie; Mandapat, Christigale; Manning, Gerard; Mariotti, Marco; Mata, Robert; Mathew, Tittu; Neumann, Tobias; Newsham, Irene; Ngo, Dinh N.; Ninova, Maria; Okwuonu, Geoffrey; Ongeri, Fiona; Palmer, William J.; Patil, Shobha; Patraquim, Pedro; Pham, Christopher; Pu, Ling-Ling; Putman, Nicholas H.; Rabouille, Catherine; Ramos, Olivia Mendivil; Rhodes, Adelaide C.; Robertson, Helen E.; Robertson, Hugh M.; Ronshaugen, Matthew; Rozas, Julio; Saada, Nehad; Sánchez-Gracia, Alejandro; Scherer, Steven E.; Schurko, Andrew M.; Siggens, Kenneth W.; Simmons, DeNard; Stief, Anna; Stolle, Eckart; Telford, Maximilian J.; Tessmar-Raible, Kristin; Thornton, Rebecca; van der Zee, Maurijn; von Haeseler, Arndt; Williams, James M.; Willis, Judith H.; Wu, Yuanqing; Zou, Xiaoyan; Lawson, Daniel; Muzny, Donna M.; Worley, Kim C.; Gibbs, Richard A.; Akam, Michael; Richards, Stephen

    2014-01-01

    Myriapods (e.g., centipedes and millipedes) display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We present an analysis of the genome of the centipede Strigamia maritima. It retains a compact genome that has undergone less gene loss and shuffling than previously sequenced arthropods, and many orthologues of genes conserved from the bilaterian ancestor that have been lost in insects. Our analysis locates many genes in conserved macro-synteny contexts, and many small-scale examples of gene clustering. We describe several examples where S. maritima shows different solutions from insects to similar problems. The insect olfactory receptor gene family is absent from S. maritima, and olfaction in air is likely effected by expansion of other receptor gene families. For some genes S. maritima has evolved paralogues to generate coding sequence diversity, where insects use alternate splicing. This is most striking for the Dscam gene, which in Drosophila generates more than 100,000 alternate splice forms, but in S. maritima is encoded by over 100 paralogues. We see an intriguing linkage between the absence of any known photosensory proteins in a blind organism and the additional absence of canonical circadian clock genes. The phylogenetic position of myriapods allows us to identify where in arthropod phylogeny several particular molecular mechanisms and traits emerged. For example, we conclude that juvenile hormone signalling evolved with the emergence of the exoskeleton in the arthropods and that RR-1 containing cuticle proteins evolved in the lineage leading to Mandibulata. We also identify when various gene expansions and losses occurred. The genome of S. maritima offers us a unique glimpse into the ancestral arthropod genome, while also displaying many adaptations to its specific

  13. Secondary succession of arthropods and plants in the Arizona Sonoran Desert in response to transmission-line construction

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, C.D.; Beley, J.R.; Ditsworth, T.M.; Butt, S.M.

    1983-03-01

    At a site about 16 km south of Black Canyon City, Arizona, density of arthropods on an undisturbed plot after an access road was built for powerline construction was much greater than on a disturbed plot. Mites, springtails, leafhoppers, scale insects, ants and thrips were significantly reduced on the disturbed area. Diversity increased on the disturbed plot after construction, but density decreased. A slight increase in similarity (H', Clambda) of the arthropod communities of the two plots appears to be related to the modest increase in cover on the disturbed area. Globe-mallow, goosefoot and a four-o'clock were pioneer species and occurred only on the disturbed area. There was a significant reduction in cover of all plant species on the disturbed plot after construction, but there was a steady increase of annual forbs at the end of the study. The results indicate that restoration of numbers of arthropods on the disturbed area is dependent on the total plant cover on the plot, apparently regardless of the composition of the plant species involved. It is obvious in this area that the plant communities will remain dissimilar, with the pioneering herbaceous plants on the disturbed plot dominating. Construction of a powerline apparently has had little impact on the structure of the arthropod community on the disturbed area, as proportions of three trophic categories of arthropods have not been radically altered. The results of this study, when compared to other studies in the Sonoran Desert and in desert grasslands disturbed by powerline construction, indicate that lengthy secondary succession does occur in the Sonoran Desert. Early arthropod invaders were found to be mainly herbivores, with few parasites or predators, and an equilibrium was eventually reached between colonizers and space requirements. 35 references, 3 figures, 3 tables

  14. The first myriapod genome sequence reveals conservative arthropod gene content and genome organisation in the centipede Strigamia maritima.

    Directory of Open Access Journals (Sweden)

    Ariel D Chipman

    2014-11-01

    Full Text Available Myriapods (e.g., centipedes and millipedes display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We present an analysis of the genome of the centipede Strigamia maritima. It retains a compact genome that has undergone less gene loss and shuffling than previously sequenced arthropods, and many orthologues of genes conserved from the bilaterian ancestor that have been lost in insects. Our analysis locates many genes in conserved macro-synteny contexts, and many small-scale examples of gene clustering. We describe several examples where S. maritima shows different solutions from insects to similar problems. The insect olfactory receptor gene family is absent from S. maritima, and olfaction in air is likely effected by expansion of other receptor gene families. For some genes S. maritima has evolved paralogues to generate coding sequence diversity, where insects use alternate splicing. This is most striking for the Dscam gene, which in Drosophila generates more than 100,000 alternate splice forms, but in S. maritima is encoded by over 100 paralogues. We see an intriguing linkage between the absence of any known photosensory proteins in a blind organism and the additional absence of canonical circadian clock genes. The phylogenetic position of myriapods allows us to identify where in arthropod phylogeny several particular molecular mechanisms and traits emerged. For example, we conclude that juvenile hormone signalling evolved with the emergence of the exoskeleton in the arthropods and that RR-1 containing cuticle proteins evolved in the lineage leading to Mandibulata. We also identify when various gene expansions and losses occurred. The genome of S. maritima offers us a unique glimpse into the ancestral arthropod genome, while also displaying many adaptations

  15. Comparative diversity of arthropods on Bt maize and non-Bt maize in two different cropping systems in South Africa.

    Science.gov (United States)

    Truter, J; Van Hamburg, H; Van Den Berg, J

    2014-02-01

    The biodiversity of an agroecosystem is not only important for its intrinsic value but also because it influences ecological functions that are vital for crop production in sustainable agricultural systems and the surrounding environment. A concern about genetically modified (GM) crops is the potential negative impact that such crops could have on diversity and abundance of nontarget organisms, and subsequently on ecosystem functions. Therefore, it is essential to assess the potential environmental risk of the release of a GM crop and to study its effect on species assemblages within that ecosystem. Assessment of the impact of Bt maize on the environment is hampered by the lack of basic checklists of species present in maize agroecosystems. The aims of the study were to compile a checklist of arthropods that occur on maize in South Africa and to compare the diversity and abundance of arthropods and functional groups on Bt maize and non-Bt maize. Collections of arthropods were carried out during two growing seasons on Bt maize and non-Bt maize plants at two localities. Three maize fields were sampled per locality during each season. Twenty plants, each of Bt maize and non-Bt maize, were randomly selected from the fields at each site. The arthropods collected during this study were classified to morphospecies level and grouped into the following functional groups: detritivores, herbivores, predators, and parasitoids. Based on feeding strategy, herbivores and predators were further divided into sucking herbivores or predators (piercing-sucking mouthparts) and chewing herbivores or predators (chewing mouthparts). A total of 8,771 arthropod individuals, comprising 288 morphospecies and presenting 20 orders, were collected. Results from this short-term study indicated that abundance and diversity of arthropods in maize and the different functional guilds were not significantly affected by Bt maize, either in terms of diversity or abundance.

  16. The first myriapod genome sequence reveals conservative arthropod gene content and genome organisation in the centipede Strigamia maritima.

    Science.gov (United States)

    Chipman, Ariel D; Ferrier, David E K; Brena, Carlo; Qu, Jiaxin; Hughes, Daniel S T; Schröder, Reinhard; Torres-Oliva, Montserrat; Znassi, Nadia; Jiang, Huaiyang; Almeida, Francisca C; Alonso, Claudio R; Apostolou, Zivkos; Aqrawi, Peshtewani; Arthur, Wallace; Barna, Jennifer C J; Blankenburg, Kerstin P; Brites, Daniela; Capella-Gutiérrez, Salvador; Coyle, Marcus; Dearden, Peter K; Du Pasquier, Louis; Duncan, Elizabeth J; Ebert, Dieter; Eibner, Cornelius; Erikson, Galina; Evans, Peter D; Extavour, Cassandra G; Francisco, Liezl; Gabaldón, Toni; Gillis, William J; Goodwin-Horn, Elizabeth A; Green, Jack E; Griffiths-Jones, Sam; Grimmelikhuijzen, Cornelis J P; Gubbala, Sai; Guigó, Roderic; Han, Yi; Hauser, Frank; Havlak, Paul; Hayden, Luke; Helbing, Sophie; Holder, Michael; Hui, Jerome H L; Hunn, Julia P; Hunnekuhl, Vera S; Jackson, LaRonda; Javaid, Mehwish; Jhangiani, Shalini N; Jiggins, Francis M; Jones, Tamsin E; Kaiser, Tobias S; Kalra, Divya; Kenny, Nathan J; Korchina, Viktoriya; Kovar, Christie L; Kraus, F Bernhard; Lapraz, François; Lee, Sandra L; Lv, Jie; Mandapat, Christigale; Manning, Gerard; Mariotti, Marco; Mata, Robert; Mathew, Tittu; Neumann, Tobias; Newsham, Irene; Ngo, Dinh N; Ninova, Maria; Okwuonu, Geoffrey; Ongeri, Fiona; Palmer, William J; Patil, Shobha; Patraquim, Pedro; Pham, Christopher; Pu, Ling-Ling; Putman, Nicholas H; Rabouille, Catherine; Ramos, Olivia Mendivil; Rhodes, Adelaide C; Robertson, Helen E; Robertson, Hugh M; Ronshaugen, Matthew; Rozas, Julio; Saada, Nehad; Sánchez-Gracia, Alejandro; Scherer, Steven E; Schurko, Andrew M; Siggens, Kenneth W; Simmons, DeNard; Stief, Anna; Stolle, Eckart; Telford, Maximilian J; Tessmar-Raible, Kristin; Thornton, Rebecca; van der Zee, Maurijn; von Haeseler, Arndt; Williams, James M; Willis, Judith H; Wu, Yuanqing; Zou, Xiaoyan; Lawson, Daniel; Muzny, Donna M; Worley, Kim C; Gibbs, Richard A; Akam, Michael; Richards, Stephen

    2014-11-01

    Myriapods (e.g., centipedes and millipedes) display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We present an analysis of the genome of the centipede Strigamia maritima. It retains a compact genome that has undergone less gene loss and shuffling than previously sequenced arthropods, and many orthologues of genes conserved from the bilaterian ancestor that have been lost in insects. Our analysis locates many genes in conserved macro-synteny contexts, and many small-scale examples of gene clustering. We describe several examples where S. maritima shows different solutions from insects to similar problems. The insect olfactory receptor gene family is absent from S. maritima, and olfaction in air is likely effected by expansion of other receptor gene families. For some genes S. maritima has evolved paralogues to generate coding sequence diversity, where insects use alternate splicing. This is most striking for the Dscam gene, which in Drosophila generates more than 100,000 alternate splice forms, but in S. maritima is encoded by over 100 paralogues. We see an intriguing linkage between the absence of any known photosensory proteins in a blind organism and the additional absence of canonical circadian clock genes. The phylogenetic position of myriapods allows us to identify where in arthropod phylogeny several particular molecular mechanisms and traits emerged. For example, we conclude that juvenile hormone signalling evolved with the emergence of the exoskeleton in the arthropods and that RR-1 containing cuticle proteins evolved in the lineage leading to Mandibulata. We also identify when various gene expansions and losses occurred. The genome of S. maritima offers us a unique glimpse into the ancestral arthropod genome, while also displaying many adaptations to its specific

  17. Optimality Conditions in Vector Optimization

    CERN Document Server

    Jiménez, Manuel Arana; Lizana, Antonio Rufián

    2011-01-01

    Vector optimization is continuously needed in several science fields, particularly in economy, business, engineering, physics and mathematics. The evolution of these fields depends, in part, on the improvements in vector optimization in mathematical programming. The aim of this Ebook is to present the latest developments in vector optimization. The contributions have been written by some of the most eminent researchers in this field of mathematical programming. The Ebook is considered essential for researchers and students in this field.

  18. The first myriapod genome sequence reveals conservative arthropod gene content and genome organisation in the centipede Strigamia maritima

    DEFF Research Database (Denmark)

    Chipman, Ariel D.; Ferrier, David E.K.; Brena, Carlo;

    2014-01-01

    Myriapods (e.g., centipedes and millipedes) display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We pres...

  19. Scientific Opinion addressing the state of the science on risk assessment of plant protection products for non-target arthropods

    DEFF Research Database (Denmark)

    EFSA PPR Panel (EFSA Panel on Plant Protection Products and their Residues); Topping, Christopher John

    2015-01-01

    Following a request from the European Food Safety Authority, the Panel on Plant Protection Products and their Residues developed an opinion on the science to support the development of a risk assessment scheme of plant protection products for non-target arthropods. The current risk assessment...... dynamics, conducting a landscape-level risk assessment is suggested. A new risk assessment scheme is suggested which integrates modelling approaches. The main exposure routes for non-target arthropods are identified and proposals are made on how to integrate them in the risk assessment. The appropriateness...

  20. Mineral cycling in soil and litter arthropod food chains. Annual progress report, February 1, 1983-January 31, 1984

    International Nuclear Information System (INIS)

    This annual report describes progress in research on the influence of soil fauna on the general process of terrestrial decomposition. The major goal is to investigate the regulation of decomposition by soil arthropods. Methods have included radioactive tracer measurements of food chain dynamics, rates of nutrient or mineral element flow during decomposition, and simulation modeling. This year's report describes significant progress in defining the influence of soil arthropods in stimulating microbial immobilization of nutrients. Preliminary efforts to define the importance of the soil-litter macroarthropods are also reported

  1. Diurnal temperature variations affect development of a herbivorous arthropod pest and its predators.

    Science.gov (United States)

    Vangansbeke, Dominiek; Audenaert, Joachim; Nguyen, Duc Tung; Verhoeven, Ruth; Gobin, Bruno; Tirry, Luc; De Clercq, Patrick

    2015-01-01

    The impact of daily temperature variations on arthropod life history remains woefully understudied compared to the large body of research that has been carried out on the effects of constant temperatures. However, diurnal varying temperature regimes more commonly represent the environment in which most organisms thrive. Such varying temperature regimes have been demonstrated to substantially affect development and reproduction of ectothermic organisms, generally in accordance with Jensen's inequality. In the present study we evaluated the impact of temperature alternations at 4 amplitudes (DTR0, +5, +10 and +15°C) on the developmental rate of the predatory mites Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus McGregor (Acari: Phytoseiidae) and their natural prey, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae). We have modelled their developmental rates as a function of temperature using both linear and nonlinear models. Diurnally alternating temperatures resulted in a faster development in the lower temperature range as compared to their corresponding mean constant temperatures, whereas the opposite was observed in the higher temperature range. Our results indicate that Jensen's inequality does not suffice to fully explain the differences in developmental rates at constant and alternating temperatures, suggesting additional physiological responses play a role. It is concluded that diurnal temperature range should not be ignored and should be incorporated in predictive models on the phenology of arthropod pests and their natural enemies and their performance in biological control programmes. PMID:25874697

  2. The effects of heavy metal contamination on the soil arthropod community of a shooting range

    Energy Technology Data Exchange (ETDEWEB)

    Migliorini, Massimo; Pigino, Gaia; Bianchi, Nicola; Bernini, Fabio; Leonzio, Claudio

    2004-05-01

    Soils in clay pigeon shooting ranges can be seriously contaminated by heavy metals. The pellets contained in ammunition are composed of Pb, Sb, Ni, Zn, Mn and Cu. The total concentrations of these metals in soils, and the effects of their increasing levels on the arthropod community were investigated at seven sampling sites in a clay pigeon shooting range and compared with two controls. Research revealed that the spatial distribution of Pb and Sb contamination in the shot-fall area was strongly correlated with the flight path of the pellets. Ordination obtained through Redundance Analysis showed that Collembola, Protura and Diplura were positively correlated with major detected contaminants (Pb, Sb), while Symphyla showed a negative correlation with these pollutants. Determination of the soluble lead fraction in soil, and of its bioaccumulation in the saprophagous Armadillidium sordidum (Isopoda) and the predator Ocypus olens (Coleoptera), showed that a significant portion of metallic Pb from spent pellets is bioavailable in the soil and can be bioaccumulated by edaphic organisms, entering the soil trophic network, but without biomagnification. - Significant relationships were found between lead accumulation in soil from a shooting range and inhabiting arthropod communities.

  3. Sensitivity of soil arthropods for toxicants on the basis of body concentrations and exposure concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Crommentuijn, T. [National Inst. of Public Health and Environmental Protection, Bilthoven (Netherlands). Toxicology Advisory Centre; Doodeman, C.J.A.M.; Pol, J.J.C. van der; Doornekamp, A.; Gestel, C.A.M. van [Vrije Univ., Amsterdam (Netherlands). Dept. of Ecology and Ecotoxicology

    1995-12-31

    Environmental quality objectives are normally derived on the basis of laboratory experiments in which exposure concentrations are related to effects. Exposure concentrations however cannot always linearly related to effects. The accumulation pattern of a species will determine how much of the toxicant will be taken up and eliminated through different routes. For soil arthropods different accumulation patterns exist based on the physiological and anatomical design of the species. This was demonstrated by studying the time-dependent toxicity of cadmium for six soil arthropods, with differing uptake-elimination kinetics. Two different accumulation patterns could be discerned. Taxonomically related species appeared to have comparable accumulation patterns, but lethal body concentrations differed. For the springtail species Folsomia candida it was also possible to compare uptake and effects of cadmium through two different routes of uptake. Individuals were exposed through soil and through the food. The main route of uptake for this species seemed to be through the soil. The concentrations at which sublethal and lethal effects occurred were comparable when based on the basis of body concentrations but not when based on the basis of exposure concentrations in the food and in the soil. A comparison of species-sensitivities on the basis of body concentrations and exposure concentrations is made. The consequences of the use of an exposure and body concentration approach for deriving environmental quality objectives for soil will be discussed.

  4. An Ancient Transkingdom Horizontal Transfer of Penelope-Like Retroelements from Arthropods to Conifers.

    Science.gov (United States)

    Lin, Xuan; Faridi, Nurul; Casola, Claudio

    2016-01-01

    Comparative genomics analyses empowered by the wealth of sequenced genomes have revealed numerous instances of horizontal DNA transfers between distantly related species. In eukaryotes, repetitive DNA sequences known as transposable elements (TEs) are especially prone to move across species boundaries. Such horizontal transposon transfers, or HTTs, are relatively common within major eukaryotic kingdoms, including animals, plants, and fungi, while rarely occurring across these kingdoms. Here, we describe the first case of HTT from animals to plants, involving TEs known as Penelope-like elements, or PLEs, a group of retrotransposons closely related to eukaryotic telomerases. Using a combination of in situ hybridization on chromosomes, polymerase chain reaction experiments, and computational analyses we show that the predominant PLE lineage, EN(+)PLEs, is highly diversified in loblolly pine and other conifers, but appears to be absent in other gymnosperms. Phylogenetic analyses of both protein and DNA sequences reveal that conifers EN(+)PLEs, or Dryads, form a monophyletic group clustering within a clade of primarily arthropod elements. Additionally, no EN(+)PLEs were detected in 1,928 genome assemblies from 1,029 nonmetazoan and nonconifer genomes from 14 major eukaryotic lineages. These findings indicate that Dryads emerged following an ancient horizontal transfer of EN(+)PLEs from arthropods to a common ancestor of conifers approximately 340 Ma. This represents one of the oldest known interspecific transmissions of TEs, and the most conspicuous case of DNA transfer between animals and plants. PMID:27190138

  5. A Survey on Residential Areas Infestation to House Pests (Arthropods in Kashan

    Directory of Open Access Journals (Sweden)

    Rouhullah Dehghani

    2013-12-01

    Full Text Available Background: Due to importance of arthropods as urban pest, such Health and Nutritional, Textile, Structural, Storage pest and role of them in human being, this study was done to show determine of houses infestation status to urban pest (Arthropods city of Kashan in 2010. Materials and Methods: A Descriptive-analytical study has been done on houses The houses were selected by cluster random and Urban pests of them, by use of hand lens were identified. The results were analyzed using abundance tables and SPSS-11.5 software and statistic tests χP2P and fisher exact3T. Results: The results of study have shown that prevalence of urban pest, Health pest 99.6%, Nutritional pest 32.6%, textile and structural pest 37.4% were seen3T.3T Out of total houses, 98% mosquitoes, 96.4% ant, 92.6% fly, 78% cockroaches species, 56.8% spider, 37.6% termite, 34.6% storage pests, 12% clothes moth, 8.2% scorpion species, 3.6% bug, 3.2% tick and 2.6% millipede were identified. Conclusion: The prevalence of infestation urban pest is high. Mosquitoes, ant, fly and cockroach were seen more the other. So methods control training, houses protection and solid and water waste management is being suggested.

  6. Arthropod venom Hyaluronidases: biochemical properties and potential applications in medicine and biotechnology.

    Science.gov (United States)

    Bordon, Karla C F; Wiezel, Gisele A; Amorim, Fernanda G; Arantes, Eliane C

    2015-01-01

    Hyaluronidases are enzymes that mainly degrade hyaluronan, the major glycosaminoglycan of the interstitial matrix. They are involved in several pathological and physiological activities including fertilization, wound healing, embryogenesis, angiogenesis, diffusion of toxins and drugs, metastasis, pneumonia, sepsis, bacteremia, meningitis, inflammation and allergy, among others. Hyaluronidases are widely distributed in nature and the enzymes from mammalian spermatozoa, lysosomes and animal venoms belong to the subclass EC 3.2.1.35. To date, only five three-dimensional structures for arthropod venom hyaluronidases (Apis mellifera and Vespula vulgaris) were determined. Additionally, there are four molecular models for hyaluronidases from Mesobuthus martensii, Polybia paulista and Tityus serrulatus venoms. These enzymes are employed as adjuvants to increase the absorption and dispersion of other drugs and have been used in various off-label clinical conditions to reduce tissue edema. Moreover, a PEGylated form of a recombinant human hyaluronidase is currently under clinical trials for the treatment of metastatic pancreatic cancer. This review focuses on the arthropod venom hyaluronidases and provides an overview of their biochemical properties, role in the envenoming, structure/activity relationship, and potential medical and biotechnological applications. PMID:26500679

  7. Arthropod prey of Wilson's Warblers in the understory of Douglas-fir forests

    Science.gov (United States)

    Hagar, J.C.; Dugger, K.M.; Starkey, E.E.

    2007-01-01

    Availability of food resources is an important factor in avian habitat selection. Food resources for terrestrial birds often are closely related to vegetation structure and composition. Identification of plant species important in supporting food resources may facilitate vegetation management to achieve objectives for providing bird habitat. We used fecal analysis to describe the diet of adult Wilson's Warblers (Wilsonia pusilla) that foraged in the understory of Douglas-fir (Pseudotsuga menziesii) forests in western Oregon during the breeding season. We sampled arthropods at the same sites where diet data were collected, and compared abundance and biomass of prey among seven common shrub species. Wilson's Warblers ate more caterpillars (Lepidoptera larvae), flies (Diptera), beetles (Coleoptera), and Homoptera than expected based on availability. Deciduous shrubs supported higher abundances of arthropod taxa and size classes used as prey by Wilson's Warblers than did evergreen shrubs. The development and maintenance of deciduous understory vegetation in conifer forests of the Pacific Northwest may be fundamental for conservation of food webs that support breeding Wilson's Warblers and other shrub-associated, insectivorous songbirds.

  8. Diurnal temperature variations affect development of a herbivorous arthropod pest and its predators.

    Directory of Open Access Journals (Sweden)

    Dominiek Vangansbeke

    Full Text Available The impact of daily temperature variations on arthropod life history remains woefully understudied compared to the large body of research that has been carried out on the effects of constant temperatures. However, diurnal varying temperature regimes more commonly represent the environment in which most organisms thrive. Such varying temperature regimes have been demonstrated to substantially affect development and reproduction of ectothermic organisms, generally in accordance with Jensen's inequality. In the present study we evaluated the impact of temperature alternations at 4 amplitudes (DTR0, +5, +10 and +15°C on the developmental rate of the predatory mites Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus McGregor (Acari: Phytoseiidae and their natural prey, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae. We have modelled their developmental rates as a function of temperature using both linear and nonlinear models. Diurnally alternating temperatures resulted in a faster development in the lower temperature range as compared to their corresponding mean constant temperatures, whereas the opposite was observed in the higher temperature range. Our results indicate that Jensen's inequality does not suffice to fully explain the differences in developmental rates at constant and alternating temperatures, suggesting additional physiological responses play a role. It is concluded that diurnal temperature range should not be ignored and should be incorporated in predictive models on the phenology of arthropod pests and their natural enemies and their performance in biological control programmes.

  9. Multiple sources of isotopic variation in a terrestrial arthropod community: challenges for disentangling food webs.

    Science.gov (United States)

    Daugherty, Matthew P; Briggs, Cheryl J

    2007-08-01

    Documenting trophic links in a food web has traditionally required complex exclusion experiments coupled with extraordinarily labor-intensive direct observations of predator foraging. Newer techniques such as stable isotope analysis (SIA) may facilitate relatively quick and accurate assessments of consumer feeding behavior. Ratios of N and C isotopes are thought to be useful for determining species' trophic position (e.g., 1 degrees consumer, 2 degrees consumer, or omnivore) and their original carbon source (e.g., C3 or C4 plants; terrestrial or marine nutrients). Thus far, however, applications of stable isotopes to terrestrial arthropod food webs have suggested that high taxon-specific variation may undermine the effectiveness of this method. We applied stable isotope analysis to a pear orchard food web, in which biological control of a dominant pest, pear psylla (Cacopsylla pyricola), involves primarily generalist arthropod predators with a high frequency of omnivory. We found multiple sources of isotopic variation in this food web, including differences among plant tissues; time, stage, and taxon-specific differences among herbivores (despite similar feeding modes); and high taxon-specific variation among predators (with no clear evidence of omnivory). Collectively, these multiple sources of isotopic variation blur our view of the structure of this food web. Idiosyncrasies in consumer trophic shifts make ad hoc application of SIA to even moderately complex food webs intractable. SIA may not be a generally applicable "quick and dirty" method for delineating terrestrial food web structure-not without calibration of specific consumer food trophic shifts. PMID:17716468

  10. Nickel levels in arthropods associated with Ni hyperaccumulator plants from an ultramafic site in New Caledonia

    Institute of Scientific and Technical Information of China (English)

    ROBERT S. BOYD; MICHAEL A. WALL; TANGUY JAFFR(E)

    2006-01-01

    Arthropods (mainly insects) were collected from a forest site that contained at least six species of Ni hyperaccumulators. Whole body Ni analysis was performed for 12 arthropod taxa, two of which were studied at different life cycle stages. We found two Nitolerant insects. The pentatomid heteropteran Utana viridipuncta, feeding on fruits of the Ni hyperaccumulator Hybanthus austrocaledonicus, contained a mean of 2 600μg Ni/g in nymphs and 750μg Ni/g in adults. The tephritid fly Bactrocera psidii, feeding on pulp of Sebertia acuminata fruits that contained 6 900μg Ni/g, contained 420μg Ni/g as larvae that had evacuated their guts and significantly less (65μg Ni/g) as adults. European honeybees (Apis mellifera) visiting flowers of the Ni hyperaccumulator H. austrocaledonicus contained significantly more Ni (8-fold more) than those collected from flowers of Myodocarpus fraxinifolius, a non-hyperaccumulator. Our results show that some insects feed on Ni hyperaccumulator plants and that their feeding mobilizes Ni into local food webs.

  11. Arthropod and filarioid parasites associated with wild rodents in the northeast marshes of Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Marcela Lareschi

    2003-07-01

    Full Text Available During 1995, 16 species of arthropods and 2 species of filarioids, totaling 1 287 specimens were collected from 64 wild rodents captured in the Hudson Natural Reserve, Buenos Aires, Argentina. Infestation parameters and indexes were analyzed. Host specific richness was S = 6, diversity H = 1.48, and relative density RDI = 40%. High values of parasite species richness and diversity were found on Oligoryzomys delticola (S = 9; H = 1.40, Oxymycterus rufus (S = 9; H = 1.37, and Oligoryzomys flavescens (S = 9; H = 1.28, followed by Scapteromys aquaticus (S = 6; H = 0.17, and Akodon azarae (S = 4; H = 1.20. Deltamys kempi was infested only by Androlaelaps rotundus. O. delticola and O. flavescens showed the highest similarity index (O = 74.19%, followed by O. flavescens with S. aquaticus, as a result of historical processes and shared microhabitats. Considering arthropods-filarioids associations, significant affinity was observed in Litomosoides bonaerensis with Hoplopleura travassosi, Laelaps paulistanensis, and Gigantolaelaps wolffsohni.

  12. Multiscale hierarchical support vector clustering

    Science.gov (United States)

    Hansen, Michael Saas; Holm, David Alberg; Sjöstrand, Karl; Ley, Carsten Dan; Rowland, Ian John; Larsen, Rasmus

    2008-03-01

    Clustering is the preferred choice of method in many applications, and support vector clustering (SVC) has proven efficient for clustering noisy and high-dimensional data sets. A method for multiscale support vector clustering is demonstrated, using the recently emerged method for fast calculation of the entire regularization path of the support vector domain description. The method is illustrated on artificially generated examples, and applied for detecting blood vessels from high resolution time series of magnetic resonance imaging data. The obtained results are robust while the need for parameter estimation is reduced, compared to support vector clustering.

  13. Multistage vector (MSV) therapeutics.

    Science.gov (United States)

    Wolfram, Joy; Shen, Haifa; Ferrari, Mauro

    2015-12-10

    One of the greatest challenges in the field of medicine is obtaining controlled distribution of systemically administered therapeutic agents within the body. Indeed, biological barriers such as physical compartmentalization, pressure gradients, and excretion pathways adversely affect localized delivery of drugs to pathological tissue. The diverse nature of these barriers requires the use of multifunctional drug delivery vehicles that can overcome a wide range of sequential obstacles. In this review, we explore the role of multifunctionality in nanomedicine by primarily focusing on multistage vectors (MSVs). The MSV is an example of a promising therapeutic platform that incorporates several components, including a microparticle, nanoparticles, and small molecules. In particular, these components are activated in a sequential manner in order to successively address transport barriers. PMID:26264836

  14. Estimation of vector velocity

    DEFF Research Database (Denmark)

    2000-01-01

    Using a pulsed ultrasound field, the two-dimensional velocity vector can be determined with the invention. The method uses a transversally modulated ultrasound field for probing the moving medium under investigation. A modified autocorrelation approach is used in the velocity estimation. The new...... estimator automatically compensates for the axial velocity, when determining the transverse velocity by using fourth order moments rather than second order moments. The estimation is optimized by using a lag different from one in the estimation process, and noise artifacts are reduced by using averaging...... of RF samples. Further, compensation for the axial velocity can be introduced, and the velocity estimation is done at a fixed depth in tissue to reduce spatial velocity dispersion....

  15. Vector-Tensor and Vector-Vector Decay Amplitude Analysis of B0->phi K*0

    CERN Document Server

    Aubert, B; Abrams, G S; Adye, T; Ahmed, S; Alam, M S; Albert, J; Aleksan, R; Allen, M T; Allison, J; Altenburg, D D; Andreotti, M; Angelini, C; Anulli, F; Arnaud, N; Asgeirsson, D J; Aston, D; Azzolini, V; Baak, M A; Back, J J; Baldini-Ferroli, R; Band, H R; Banerjee, Sw; Bard, D J; Barlow, N R; Barlow, R J; Barrett, M; Bartoldus, R; Batignani, G; Battaglia, M; Bauer, J M; Bechtle, P; Beck, T W; Behera, P K; Bellini, F; Benayoun, M; Benelli, G; Berger, N; Bernard, D; Berryhill, J W; Best, D S; Bettarini, S; Bettoni, D; Bevan, A J; Bhimji, W; Bhuyan, B; Bianchi, F; Biasini, M; Biesiada, J; Blanc, F; Blaylock, G; Blinov, V E; Bloom, P C; Blount, N L; Bomben, M; Bondioli, M; Bonneaud, G R; Bosisio, L; Boutigny, D; Bowerman, D A; Boyd, J T; Bozzi, C; Brandenburg, G; Brandt, T; Brau, J E; Briand, H; Brown, C M; Brown, D N; Bruinsma, M; Brunet, S; Bucci, F; Buchanan, C; Bugg, W; Bukin, A D; Bula, R; Burchat, P R; Burke, J P; Button-Shafer, J; Buzzo, A; Bóna, M; Cahn, R N; Calabrese, R; Calcaterra, A; Calderini, G; Campagnari, C; Carpinelli, M; Cartaro, C; Cavallo, N; Cavoto, G; Cenci, R; Chai, X; Chaisanguanthum, K S; Chao, M; Charles, E; Charles, M J; Chauveau, J; Chavez, C A; Chen, A; Chen, C; Chen, E; Chen, J C; Chen, S; Chen, X; Chen, X R; Cheng, B; Cheng, C H; Chia, Y M; Cibinetto, G; Clark, P J; Clarke, C K; Claus, R; Cochran, J; Coleman, J P; Contri, R; Convery, M R; Corwin, L A; Cossutti, F; Cottingham, W N; Couderc, F; Covarelli, R; Cowan, G; Cowan, R; Crawley, H B; Cremaldi, L; Cunha, A; Curry, S; Côté, D; D'Orazio, A; Dahmes, B; Dallapiccola, C; Danielson, N; Dasu, S; Datta, M; Dauncey, P D; David, P; Davier, M; Davis, C L; De Nardo, Gallieno; De Sangro, R; Del Amo-Sánchez, P; Del Buono, L; Del Re, D; Della Ricca, G; Denig, A G; Di Lodovico, F; Di Marco, E; Dingfelder, J C; Dittongo, S; Dong, L; Dorfan, J; Druzhinin, V P; Dubitzky, R S; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W M; Dvoretskii, A; Ebert, M; Eckhart, E A; Eckmann, R; Edgar, C L; Edwards, A J; Egede, U; Eigen, G; Eisner, A M; Elmer, P; Emery, S; Ernst, J A; Eschenburg, V; Eschrich, I; Eyges, V; Fabozzi, F; Faccini, R; Fang, F; Feltresi, E; Ferrarotto, F; Ferroni, F; Field, R C; Finocchiaro, G; Flacco, C J; Flack, R L; Flächer, H U; Flood, K T; Ford, K E; Ford, W T; Forster, I J; Forti, F; Fortin, D; Foulkes, S D; Franek, B; Frey, R; Fritsch, M; Fry, J R; Fulsom, B G; Gabathuler, E; Gaidot, A; Gallo, F; Gamba, D; Gamet, R; Gan, K K; Ganzhur, S F; Gao, Y; Gary, J W; Gaspero, M; Gatto, C; Gaz, A; George, K A; Gill, M S; Giorgi, M A; Gladney, L; Glanzman, T; Godang, R; Golubev, V B; Gowdy, S J; Gradl, W; Graham, M T; Graugès-Pous, E; Grenier, P; Gritsan, A V; Grosdidier, G; Groysman, Y; Guo, Z J; Hadavand, H K; Haire, M; Halyo, V; Hamano, K; Hamel de Monchenault, G; Hamon, O; Harrison, P F; Harrison, T J; Hart, A J; Hartfiel, B L; Hast, C; Hauke, A; Hawkes, C M; Hearty, C; Held, T; Hertzbach, S S; Heusch, C A; Hill, E J; Hirschauer, J F; Hitlin, D G; Hollar, J J; Hong, T M; Honscheid, K; Hopkins, D A; Hrynóva, T; Hufnagel, D; Hulsbergen, W D; Hutchcroft, D E; Höcker, A; Igonkina, O; Innes, W R; Izen, J M; Jackson, P D; Jackson, P S; Jacobsen, R G; Jain, V; Jasper, H; Jawahery, A; Jessop, C P; Judd, D; Kadyk, J A; Kagan, H; Karyotakis, Yu; Kass, R; Kelsey, M H; Kerth, L T; Khan, A; Kim, H; Kim, P; Kirkby, D; Klose, V; Knecht, N S; Koch, H; Kolb, J A; Kolomensky, Yu G; Kovalskyi, D; Kowalewski, R V; Kozanecki, Witold; Kreisel, A; Krishnamurthy, M; Kroeger, R; Kroseberg, J; Kukartsev, G; Kutter, P E; Kyberd, P; La Vaissière, C de; Lacker, H M; Lae, C K; Lafferty, G D; Lanceri, L; Lange, D J; Lankford, A J; Latham, T E; Latour, E; Lau, Y P; Lazzaro, A; Le Diberder, F R; Lee, C L; Lees, J P; Legendre, M; Leith, D W G S; Lepeltier, V; Leruste, P; Lewandowski, B; Li Gioi, L; Li, S; Li, X; Lista, L; Liu, H; Lo Vetere, M; LoSecco, J M; Lockman, W S; Lombardo, V; Long, O; Lopes-Pegna, D; Lopez-March, N; Lou, X C; Lu, M; Luitz, S; Lund, P; Luppi, E; Lusiani, A; Lutz, A M; Lynch, G; Lynch, H L; Lü, C; Lüth, V; MacFarlane, D B; Macri, M M; Mader, W F; Majewski, S A; Malcles, J; Mallik, U; Mancinelli, G; Mandelkern, M A; Marchiori, G; Margoni, M; Marks, J; Marsiske, H; Martínez-Vidal, F; Mattison, T S; Mazur, M A; Mazzoni, M A; McKenna, J A; McMahon, T R; Mclachlin, S E; Meadows, B T; Mellado, B; Menges, W; Merkel, J; Messner, R; Meyer, N T; Meyer, W T; Mihályi, A; Mir, L M; Mishra, K; Mohanty, G B; Monge, M R; Monorchio, D; Moore, T B; Morandin, M; Morganti, M; Morganti, S; Morii, M; Muheim, F; Müller, D R; Nagel, M; Naisbit, M T; Narsky, I; Nash, J A; Nauenberg, U; Neal, H; Negrini, M; Neri, N; Nesom, G; Nicholson, H; Nikolich, M B; Nogowski, R; Nugent, I M; O'Grady, C P; Ocariz, J; Ofte, I; Olaiya, E O; Olivas, A; Olsen, J; Onuchin, A P; Orimoto, T J; Oyanguren, A; Ozcan, V E; Paar, H P; Pacetti, S; Palano, A; Palombo, F; Pan, B; Pan, Y; Panduro, W; Paoloni, E; Paolucci, P; Pappagallo, M; Park, W; Passaggio, S; Patel, P M; Patrignani, C; Patteri, P; Payne, D J; Pelizaeus, M; Perazzo, A; Perl, M; Peruzzi, I M; Peters, K; Petersen, B A; Petrella, A; Petzold, A; Piatenko, T; Piccolo, D; Piccolo, M; Piemontese, L; Pierini, M; Piredda, G; Playfer, S; Poireau, V; Polci, F; Pompili, A; Porter, F C; Posocco, M; Potter, C T; Prell, S; Prencipe, E; Prepost, R; Pripstein, M; Pruvot, S; Pulliam, T; Purohit, M V; Qi, N D; Rahatlou, S; Rahimi, A M; Rahmat, R; Rama, M; Ratcliff, B N; Raven, G; Regensburger, J J; Ricciardi, S; Richman, J D; Ritchie, J L; Rizzo, G; Roberts, D A; Robertson, A I; Robertson, S H; Robutti, E; Rodier, S; Roe, N A; Ronan, M T; Roney, J M; Rong, G; Roodman, A; Roos, L; Rosenberg, E I; Rotondo, M; Roudeau, P; Rubin, A E; Ruddick, W O; Röthel, W; Sacco, R; Saeed, M A; Safai-Tehrani, F; Saleem, M; Salnikov, A A; Salvatore, F; Sanders, D A; Santroni, A; Saremi, S; Satpathy, A; Schalk, T; Schenk, S; Schilling, C J; Schindler, R H; Schofield, K C; Schott, G; Schröder, T; Schröder, H; Schubert, J; Schubert, K R; Schumm, B A; Schune, M H; Schwiening, J; Schwierz, R; Schwitters, R F; Sciacca, C; Sciolla, G; Seiden, A; Sekula, S J; Serednyakov, S I; Serrano, J; Sharma, V; Shen, B C; Sherwood, D J; Simard, M; Simi, G; Simonetto, F; Sinev, N B; Skovpen, Yu I; Smith, A J S; Smith, J G; Snoek, H L; Snyder, A; Sobie, R J; Soffer, A; Sokoloff, M D; Solodov, E P; Spaan, B; Spanier, S M; Spitznagel, M; Spradlin, P; Steinke, M; Stelzer, J; Stocchi, A; Stoker, D P; Stroili, R; Strom, D; Strube, J; Stugu, B; Stängle, H; Su, D; Sullivan, M K; Summers, D J; Sundermann, J E; Suzuki, K; Swain, S K; Taras, P; Taylor, F; Telnov, A V; Teodorescu, L; Ter-Antonian, R; Therin, G; Thiebaux, C; Thompson, J M; Tisserand, V; Todyshev, Y K; Toki, W H; Torrence, E; Tosi, S; Touramanis, C; Ulmer, K A; Uwer, U; Van Bakel, N; Vasseur, G; Vavra, J; Vazquez, A; Verderi, M; Viaud, F B; Vitale, L; Voci, C; Voena, C; Volk, A; Wagner, A P; Wagner, S R; Wagoner, D E; Waldi, R; Walker, D; Walsh, J J; Wang, K; Wang, P; Wang, W F; Wappler, F R; Watson, A T; Weaver, M; Weinstein, A J R; Wenzel, W A; Wilden, L; Williams, D C; Williams, J C; Wilson, F F; Wilson, J R; Wilson, M G; Wilson, R J; Winklmeier, F; Wisniewski, W J; Wittgen, M; Wong, Q K; Wormser, G; Wren, A C; Wright, D H; Wright, D M; Wu, J; Wu, S L; Wulsin, H W; Xie, Y; Yamamoto, R K; Yarritu, A K; Ye, S; Yi, J I; Yi, K; Young, C C; Yu, Z; Yéche, C; Zain, S B; Zallo, A; Zeng, Q; Zghiche, A; Zhang, J; Zhang, L; Zhao, H W; Zhu, Y S; Ziegler, V; Zito, M; Çuhadar-Dönszelmann, T; al, et

    2007-01-01

    We perform an amplitude analysis of the decays B0->phi K^*_2(1430)0, phi K^*(892)0, and phi(K pi)^0_S-wave with a sample of about 384 million BBbar pairs recorded with the BABAR detector. The fractions of longitudinal polarization f_L of the vector-tensor and vector-vector decay modes are measured to be 0.853 +0.061-0.069 +-0.036 and 0.506 +-0.040 +-0.015, respectively. Overall, twelve parameters are measured for the vector-vector decay and seven parameters for the vector-tensor decay, including the branching fractions and parameters sensitive to CP-violation.

  16. Mitogenomes reveal diversity of the European Lyme borreliosis vector Ixodes ricinus in Italy.

    Science.gov (United States)

    Carpi, Giovanna; Kitchen, Andrew; Kim, Hie Lim; Ratan, Aakrosh; Drautz-Moses, Daniela I; McGraw, John J; Kazimirova, Maria; Rizzoli, Annapaola; Schuster, Stephan C

    2016-08-01

    In Europe, the Ixodes ricinus tick is the most important vector of the etiological agents of Lyme borreliosis and several other emerging tick-borne diseases. Because tick-borne pathogens are dependent on their vectors for transmission, understanding the vector population structure is crucial to inform public health research of pathogen dynamics and spread. However, the population structure and dynamics of this important vector species are not well understood as most genetic studies utilize short mitochondrial and nuclear sequences with little diversity. Herein we obtained and analyzed complete mitochondrial genome (hereafter "mitogenome") sequences to better understand the genetic diversity and the population structure of I. ricinus from two long-standing tick-borne disease foci in northern Italy. Complete mitogenomes of 23 I. ricinus ticks were sequenced at high coverage. Out of 23 mitogenome sequences we identified 17 unique haplotypes composed of 244 segregating sites. Phylogenetic reconstruction using 18 complete mitogenome sequences revealed the coexistence of four highly divergent I. ricinus maternal lineages despite the narrow spatial scale over which these samples were obtained (100km). Notably, the estimated coalescence time of the 18 mitogenome haplotypes is ∼427 thousand years ago (95% HPD 330, 540). This divergence between I. ricinus lineages is consistent with the mitochondrial diversity of other arthropod vector species and indicates that long-term I. ricinus populations may have been less structured and larger than previously thought. Thus, this study suggests that a rapid and accurate retrieval of full mitochondrial genomes from this disease vector enables fine-resolution studies of tick intraspecies genetic relationships, population differentiation, and demographic history. PMID:27165938

  17. International network for capacity building for the control of emerging viral vector-borne zoonotic diseases: ARBO-ZOONET.

    Science.gov (United States)

    Ahmed, J; Bouloy, M; Ergonul, O; Fooks, Ar; Paweska, J; Chevalier, V; Drosten, C; Moormann, R; Tordo, N; Vatansever, Z; Calistri, P; Estrada-Pena, A; Mirazimi, A; Unger, H; Yin, H; Seitzer, U

    2009-03-26

    Arboviruses are arthropod-borne viruses, which include West Nile fever virus (WNFV), a mosquito-borne virus, Rift Valley fever virus (RVFV), a mosquito-borne virus, and Crimean-Congo haemorrhagic fever virus (CCHFV), a tick-borne virus. These arthropod-borne viruses can cause disease in different domestic and wild animals and in humans, posing a threat to public health because of their epidemic and zoonotic potential. In recent decades, the geographical distribution of these diseases has expanded. Outbreaks of WNF have already occurred in Europe, especially in the Mediterranean basin. Moreover, CCHF is endemic in many European countries and serious outbreaks have occurred, particularly in the Balkans, Turkey and Southern Federal Districts of Russia. In 2000, RVF was reported for the first time outside the African continent, with cases being confirmed in Saudi Arabia and Yemen. This spread was probably caused by ruminant trade and highlights that there is a threat of expansion of the virus into other parts of Asia and Europe. In the light of global warming and globalisation of trade and travel, public interest in emerging zoonotic diseases has increased. This is especially evident regarding the geographical spread of vector-borne diseases. A multi-disciplinary approach is now imperative, and groups need to collaborate in an integrated manner that includes vector control, vaccination programmes, improved therapy strategies, diagnostic tools and surveillance, public awareness, capacity building and improvement of infrastructure in endemic regions. PMID:19341603

  18. International network for capacity building for the control of emerging viral vector-borne zoonotic diseases: ARBO-ZOONET.

    Science.gov (United States)

    Ahmed, J; Bouloy, M; Ergonul, O; Fooks, Ar; Paweska, J; Chevalier, V; Drosten, C; Moormann, R; Tordo, N; Vatansever, Z; Calistri, P; Estrada-Pena, A; Mirazimi, A; Unger, H; Yin, H; Seitzer, U

    2009-03-26

    Arboviruses are arthropod-borne viruses, which include West Nile fever virus (WNFV), a mosquito-borne virus, Rift Valley fever virus (RVFV), a mosquito-borne virus, and Crimean-Congo haemorrhagic fever virus (CCHFV), a tick-borne virus. These arthropod-borne viruses can cause disease in different domestic and wild animals and in humans, posing a threat to public health because of their epidemic and zoonotic potential. In recent decades, the geographical distribution of these diseases has expanded. Outbreaks of WNF have already occurred in Europe, especially in the Mediterranean basin. Moreover, CCHF is endemic in many European countries and serious outbreaks have occurred, particularly in the Balkans, Turkey and Southern Federal Districts of Russia. In 2000, RVF was reported for the first time outside the African continent, with cases being confirmed in Saudi Arabia and Yemen. This spread was probably caused by ruminant trade and highlights that there is a threat of expansion of the virus into other parts of Asia and Europe. In the light of global warming and globalisation of trade and travel, public interest in emerging zoonotic diseases has increased. This is especially evident regarding the geographical spread of vector-borne diseases. A multi-disciplinary approach is now imperative, and groups need to collaborate in an integrated manner that includes vector control, vaccination programmes, improved therapy strategies, diagnostic tools and surveillance, public awareness, capacity building and improvement of infrastructure in endemic regions.

  19. Testing identifiablility of cointegrating vectors

    NARCIS (Netherlands)

    H.P. Boswijk

    1996-01-01

    This article analyzes the identification and normalization of cointegrating vectors. Normalizing a cointegrating relation with respect to one of the relevant variables is with loss of generality; and restrictions that are supposed to identify a vector may fail to do so for particular parameter value

  20. Estimation of Motion Vector Fields

    DEFF Research Database (Denmark)

    Larsen, Rasmus

    1993-01-01

    This paper presents an approach to the estimation of 2-D motion vector fields from time varying image sequences. We use a piecewise smooth model based on coupled vector/binary Markov random fields. We find the maximum a posteriori solution by simulated annealing. The algorithm generate sample...

  1. Vectors on the Basketball Court

    Science.gov (United States)

    Bergman, Daniel

    2010-01-01

    An Idea Bank published in the April/May 2009 issue of "The Science Teacher" describes an experiential physics lesson on vectors and vector addition (Brown 2009). Like its football predecessor, the basketball-based investigation presented in this Idea Bank addresses National Science Education Standards Content B, Physical Science, 9-12 (NRC 1996)…

  2. Rice Reoviruses in Insect Vectors.

    Science.gov (United States)

    Wei, Taiyun; Li, Yi

    2016-08-01

    Rice reoviruses, transmitted by leafhopper or planthopper vectors in a persistent propagative manner, seriously threaten the stability of rice production in Asia. Understanding the mechanisms that enable viral transmission by insect vectors is a key to controlling these viral diseases. This review describes current understanding of replication cycles of rice reoviruses in vector cell lines, transmission barriers, and molecular determinants of vector competence and persistent infection. Despite recent breakthroughs, such as the discoveries of actin-based tubule motility exploited by viruses to overcome transmission barriers and mutually beneficial relationships between viruses and bacterial symbionts, there are still many gaps in our knowledge of transmission mechanisms. Advances in genome sequencing, reverse genetics systems, and molecular technologies will help to address these problems. Investigating the multiple interaction systems among the virus, insect vector, insect symbiont, and plant during natural infection in the field is a central topic for future research on rice reoviruses. PMID:27296147

  3. Octonionic Reformulation of Vector Analysis

    CERN Document Server

    Chauhan, Bhupendra C S; Negi, O P S

    2010-01-01

    According to celebrated Hurwitz theorem, there exists four division algebras consisting of R (real numbers), C (complex numbers), H (quaternions) and O (octonions). Keeping in view the utility of octonion variable we have tried to extend the three dimensional vector analysis to seven dimensional one. Starting with the scalar and vector product in seven dimensions, we have redefined the gradient, divergence and curl in seven dimension. It is shown that the identity n(n-1)(n-3)(n-7)=0 is satisfied only for 0, 1, 3 and 7 dimensional vectors. We have tried to write all the vector inequalities and formulas in terms of seven dimensions and it is shown that same formulas loose their meaning in seven dimensions due to non-associativity of octonions. The vector formulas are retained only if we put certain restrictions on octonions and split octonions.

  4. Short-term effects of different genetically modified maize varieties on arthropod food web properties: an experimental field assessment.

    Science.gov (United States)

    Szénási, Ágnes; Pálinkás, Zoltán; Zalai, Mihály; Schmitz, Oswald J; Balog, Adalbert

    2014-01-01

    There is concern that genetically modified (GM) plants may have adverse affects on the arthropod biodiversity comprising agricultural landscapes. The present study report on a two year field experimental test of whether four different genotypic lines, some are novel with no previous field tests, of GM maize hybrids alter the structure of arthropod food webs that they harbour, relative to non-GM maize (control) that is widely used in agriculture. The different GM genotypes produced either Bt toxins, conferred glyphosate tolerance or a combination of the two traits. Quantitative food web analysis, based on short-term assessment assigning a total of 243,896 arthropod individuals collected from the treatments to their positions in food webs, revealed that complex and stable food webs persisted in each maize treatment. Moreover, food web structure remained relatively unchanged by the GM-genotype. The results suggest that at least in short-term period these particular GM maize genotypes will not have adverse effects on arthropod biota of agricultural landscapes.

  5. Arthropod Pests and Predators Associated With Bittersweet Nightshade, a Noncrop Host of the Potato Psyllid (Hemiptera: Triozidae).

    Science.gov (United States)

    Castillo Carrillo, C I; Fu, Z; Jensen, A S; Snyder, W E

    2016-08-01

    Bittersweet nightshade (Solanum dulcamara L.) is a key noncrop host of the potato psyllid (Bactericera cockerelli Šulc), proposed to be a source of the psyllids that colonize potato (Solanum tuberosum L.) fields in the northwestern United States. Here, we describe the broader community of arthropod potato pests, and also predatory arthropods, found in bittersweet nightshade patches. Over 2 yr, we sampled arthropods in patches of this weed spanning the potato-growing region of eastern Washington State. The potato psyllid was the most abundant potato pest that we found, with reproduction of these herbivores recorded throughout much of the growing season where this was measured. Aphid, beetle, and thrips pests of potato also were collected on bittersweet nightshade. In addition to these herbivores, we found a diverse community of >40 predatory arthropod taxa. Spiders, primarily in the Families Dictynidae and Philodromidae, made up 70% of all generalist predator individuals collected. Other generalist predators included multiple species of predatory mites, bugs, and beetles. The coccinellid beetle Stethorus punctillum (Weise) was observed eating psyllid eggs, while the parasitoid wasp Tamarixia triozae (Burks) was observed parasitizing potato psyllid nymphs. Overall, our survey verified the role of bittersweet nightshade as a potato psyllid host, while suggesting that other potato pests also use these plants. At the same time, we found that bittersweet nightshade patches were associated with species-rich communities of natural enemies. Additional work is needed to directly demonstrate movement of pests, and perhaps also predators, from bittersweet nightshade to potato fields. PMID:27357162

  6. Effects of the emerald ash borer invasion on the community composition of arthropods associated with ash tree boles

    Science.gov (United States)

    Emerald ash borer (EAB), Agrilus planipennis Fairmaire is an invasive non-native wood-boring beetle that has killed hundreds of millions of ash trees (Fraxinus spp.) in North America, and threatens to extirpate the ecological services provided by the genus. Identifying the arthropod community assoc...

  7. The siren song of a sticky plant: Columbines provision mutualist arthropods by attracting and killing passerby insects.

    Science.gov (United States)

    LoPresti, E F; Pearse, I S; Charles, G K

    2015-11-01

    Many plants provide predatory arthropods with food or shelter. Glandular trichomes entrap insects and may provision predators with insect carrion, though it has not been clear whether this putative benefit functions with natural amounts of carrion, whether plants actively attract insect "tourists," and how common this provisioning system is. We tested the hypothesis that a sticky columbine (Aquilegia eximia: Ranunculaceae) attracts passerby arthropods (a siren song leading them to their demise); that these entrapped arthropods increased predators on the plant; and that these predators reduced damage to the plant. Sticky traps baited with columbine peduncles entrapped more arthropod carrion than unbaited control traps. Predator abundance correlated positively with carrion abundance observationally, and experimental removal of carrion reduced predator numbers. Experimental removal of carrion also increased damage to reproductive structures, likely due to reductions in predator numbers. This indirect defense may be common; we compiled a list of insect-trapping sticky plants that includes over 110 genera in 49 families, suggesting a widespread convergence of this trait, even in non-carnivorous plants. The ubiquity of this trait combined with these experiments suggest that carrion entrapment should be viewed as a common and active process mediated by the plant for indirect defense.

  8. Potential and limitations of X-Ray micro-computed tomography in arthropod neuroanatomy: a methodological and comparative survey.

    Science.gov (United States)

    Sombke, Andy; Lipke, Elisabeth; Michalik, Peter; Uhl, Gabriele; Harzsch, Steffen

    2015-06-01

    Classical histology or immunohistochemistry combined with fluorescence or confocal laser scanning microscopy are common techniques in arthropod neuroanatomy, and these methods often require time-consuming and difficult dissections and sample preparations. Moreover, these methods are prone to artifacts due to compression and distortion of tissues, which often result in information loss and especially affect the spatial relationships of the examined parts of the nervous system in their natural anatomical context. Noninvasive approaches such as X-ray micro-computed tomography (micro-CT) can overcome such limitations and have been shown to be a valuable tool for understanding and visualizing internal anatomy and structural complexity. Nevertheless, knowledge about the potential of this method for analyzing the anatomy and organization of nervous systems, especially of taxa with smaller body size (e.g., many arthropods), is limited. This study set out to analyze the brains of selected arthropods with micro-CT, and to compare these results with available histological and immunohistochemical data. Specifically, we explored the influence of different sample preparation procedures. Our study shows that micro-CT is highly suitable for analyzing arthropod neuroarchitecture in situ and allows specific neuropils to be distinguished within the brain to extract quantitative data such as neuropil volumes. Moreover, data acquisition is considerably faster compared with many classical histological techniques. Thus, we conclude that micro-CT is highly suitable for targeting neuroanatomy, as it reduces the risk of artifacts and is faster than classical techniques. PMID:25728683

  9. The siren song of a sticky plant: Columbines provision mutualist arthropods by attracting and killing passerby insects.

    Science.gov (United States)

    LoPresti, E F; Pearse, I S; Charles, G K

    2015-11-01

    Many plants provide predatory arthropods with food or shelter. Glandular trichomes entrap insects and may provision predators with insect carrion, though it has not been clear whether this putative benefit functions with natural amounts of carrion, whether plants actively attract insect "tourists," and how common this provisioning system is. We tested the hypothesis that a sticky columbine (Aquilegia eximia: Ranunculaceae) attracts passerby arthropods (a siren song leading them to their demise); that these entrapped arthropods increased predators on the plant; and that these predators reduced damage to the plant. Sticky traps baited with columbine peduncles entrapped more arthropod carrion than unbaited control traps. Predator abundance correlated positively with carrion abundance observationally, and experimental removal of carrion reduced predator numbers. Experimental removal of carrion also increased damage to reproductive structures, likely due to reductions in predator numbers. This indirect defense may be common; we compiled a list of insect-trapping sticky plants that includes over 110 genera in 49 families, suggesting a widespread convergence of this trait, even in non-carnivorous plants. The ubiquity of this trait combined with these experiments suggest that carrion entrapment should be viewed as a common and active process mediated by the plant for indirect defense. PMID:27070006

  10. Confirmation of Romer's Gap as a low oxygen interval constraining the timing of initial arthropod and vertebrate terrestrialization.

    Science.gov (United States)

    Ward, Peter; Labandeira, Conrad; Laurin, Michel; Berner, Robert A

    2006-11-01

    The first terrestrialization of species that evolved from previously aquatic taxa was a seminal event in evolutionary history. For vertebrates, one of the most important terrestrialized groups, this event was interrupted by a time interval known as Romer's Gap, for which, until recently, few fossils were known. Here, we argue that geochronologic range data of terrestrial arthropods show a pattern similar to that of vertebrates. Thus, Romer's Gap is real, occupied an interval from 360 million years before present (MYBP) to 345 MYBP, and occurred when environmental conditions were unfavorable for air-breathing, terrestrial animals. These model results suggest that atmospheric oxygen levels were the major driver of successful terrestrialization, and a low-oxygen interval accounts for Romer's Gap. Results also show that terrestrialization among members of arthropod and vertebrate clades occurred in two distinct phases. The first phase was a 65-million-year (My) interval from 425 to 360 MYBP, representing an earlier, prolonged event of complete arthropod terrestrialization of smaller-sized forms (425-385 MYBP) and a subsequent, modest, and briefer event of incipient terrestrialization of larger-sized, aquatic vertebrates (385-360 MYBP). The second phase began at 345 MYBP, characterized by numerous new terrestrial species emerging in both major clades. The first and second terrestrialization phases bracket Romer's Gap, which represents a depauperate spectrum of major arthropod and vertebrate taxa before a major Late Paleozoic colonization of terrestrial habitats.

  11. Population bulk segregant mapping uncovers resistance mutations and the mode of action of a chitin synthesis inhibitor in arthropods

    NARCIS (Netherlands)

    T. Van Leeuwen; P. Demaeght; E.J. Osborne; W. Dermauw; S. Gohlke; R. Nauen; M. Grbić; L. Tirry; H. Merzendorfer; R.M. Clark

    2012-01-01

    Because of its importance to the arthropod exoskeleton, chitin biogenesis is an attractive target for pest control. This point is demonstrated by the economically important benzoylurea compounds that are in wide use as highly specific agents to control insect populations. Nevertheless, the target si

  12. Mineral cycling in soil and litter arthropod food chains. Three-year progress report, November 1, 1980-January 31, 1984

    International Nuclear Information System (INIS)

    This report summarizes our analysis of trophic dynamics in soil fauna including their impact on the decomposition process, investigation of relationships between soil fauna and microflora, development and testing of models describing these processes, and documentation of rates of movement of nutrients along soil arthropod food chains

  13. Emerging vector borne diseases – incidence through vectors

    Directory of Open Access Journals (Sweden)

    Sara eSavic

    2014-12-01

    Full Text Available Vector borne diseases use to be a major public health concern only in tropical and subtropical areas, but today they are an emerging threat for the continental and developed countries also. Nowdays, in intercontinetal countries, there is a struggle with emerging diseases which have found their way to appear through vectors. Vector borne zoonotic diseases occur when vectors, animal hosts, climate conditions, pathogens and susceptible human population exist at the same time, at the same place. Global climate change is predicted to lead to an increase in vector borne infectious diseases and disease outbreaks. It could affect the range and popultion of pathogens, host and vectors, transmission season, etc. Reliable surveilance for diseases that are most likely to emerge is required. Canine vector borne diseases represent a complex group of diseases including anaplasmosis, babesiosis, bartonellosis, borreliosis, dirofilariosis, erlichiosis, leishmaniosis. Some of these diseases cause serious clinical symptoms in dogs and some of them have a zoonotic potential with an effect to public health. It is expected from veterinarians in coordination with medical doctors to play a fudamental role at primeraly prevention and then treatment of vector borne diseases in dogs. The One Health concept has to be integrated into the struggle against emerging diseases.During a four year period, from 2009-2013, a total number of 551 dog samples were analysed for vector borne diseases (borreliosis, babesiosis, erlichiosis, anaplasmosis, dirofilariosis and leishmaniasis in routine laboratory work. The analysis were done by serological tests – ELISA for borreliosis, dirofilariosis and leishmaniasis, modified Knott test for dirofilariosis and blood smear for babesiosis, erlichiosis and anaplasmosis. This number of samples represented 75% of total number of samples that were sent for analysis for different diseases in dogs. Annually, on avarege more then half of the samples

  14. Aboveground and belowground arthropods experience different relative influences of stochastic versus deterministic community assembly processes following disturbance

    Science.gov (United States)

    Martinez, Alexander S.; Faist, Akasha M.

    2016-01-01

    Background Understanding patterns of biodiversity is a longstanding challenge in ecology. Similar to other biotic groups, arthropod community structure can be shaped by deterministic and stochastic processes, with limited understanding of what moderates the relative influence of these processes. Disturbances have been noted to alter the relative influence of deterministic and stochastic processes on community assembly in various study systems, implicating ecological disturbances as a potential moderator of these forces. Methods Using a disturbance gradient along a 5-year chronosequence of insect-induced tree mortality in a subalpine forest of the southern Rocky Mountains, Colorado, USA, we examined changes in community structure and relative influences of deterministic and stochastic processes in the assembly of aboveground (surface and litter-active species) and belowground (species active in organic and mineral soil layers) arthropod communities. Arthropods were sampled for all years of the chronosequence via pitfall traps (aboveground community) and modified Winkler funnels (belowground community) and sorted to morphospecies. Community structure of both communities were assessed via comparisons of morphospecies abundance, diversity, and composition. Assembly processes were inferred from a mixture of linear models and matrix correlations testing for community associations with environmental properties, and from null-deviation models comparing observed vs. expected levels of species turnover (Beta diversity) among samples. Results Tree mortality altered community structure in both aboveground and belowground arthropod communities, but null models suggested that aboveground communities experienced greater relative influences of deterministic processes, while the relative influence of stochastic processes increased for belowground communities. Additionally, Mantel tests and linear regression models revealed significant associations between the aboveground arthropod

  15. Loop-mediated isothermal amplification applied to filarial parasites detection in the mosquito vectors: Dirofilaria immitis as a study model

    Directory of Open Access Journals (Sweden)

    Nelson Bryce

    2009-03-01

    Full Text Available Abstract Background Despite recent advances in our understanding of the basic biology behind transmission of zoonotic infectious diseases harbored by arthropod vectors these diseases remain threatening public health concerns. For effective control of vector and treatment, precise sampling indicating the prevalence of such diseases is essential. With an aim to develop a quick and simple method to survey zoonotic pathogen-transmitting vectors, LAMP (loop-mediated isothermal amplification was applied to the detection of filarial parasites using a filarial parasite-transmitting experimental model that included one of the mosquito vectors, Aedes aegypti, and the canine heartworm, Dirofilaria immitis. Results LAMP reactions amplifying the cytochrome oxidase subunit I gene demonstrated high sensitivity when a single purified D. immitis microfilaria was detected. Importantly, the robustness of the LAMP reaction was revealed upon identification of an infected mosquito carrying just a single parasite, a level easily overlooked using conventional microscopic analysis. Furthermore, successful detection of D. immitis in wild-caught mosquitoes demonstrated its applicability to field surveys. Conclusion Due to its simplicity, sensitivity, and reliability, LAMP is suggested as an appropriate diagnostic method for routine diagnosis of mosquito vectors carrying filarial parasites. This method can be applied to the survey of not only canine filariasis but also lymphatic filariasis, another major public health problem. Therefore, this method offers great promise as a useful diagnostic method for filarial parasite detection in endemic filariasis regions.

  16. Mormon Cricket Control in Utah's West Desert - Evaluation of Impacts of the Pesticide Diflubenzuron on Nontarget Arthropod Communities

    Science.gov (United States)

    Graham, Tim B.; Brasher, Anne M.D.; Close, Rebecca N.

    2008-01-01

    Grasshopper and Mormon cricket (Orthoptera) populations periodically build to extremely high numbers and can cause significant economic damage in rangelands and agricultural fields of the Great Plains and Intermountain West. A variety of insecticides have been applied to control population outbreaks, with recent efforts directed at minimizing impacts to nontarget fauna in treated ecosystems. A relatively new insecticide for control of Orthoptera is diflubenzuron, which acts to inhibit chitin production, ultimately causing death during the molt following ingestion of the insecticide. All arthropods, including insects, mites, and crustaceans, use chitin to build their exoskeletons and will die if they are unable to produce it during the next molt. Diflubenzuron is not taxon specific - it affects all arthropods that ingest it, except adult insects, which do not molt. Consequently, application of this pesticide has the potential to significantly reduce not only target populations but all terrestrial and aquatic arthropods within treatment zones. Some research has been done in the Great Plains on the impact of diflubenzuron on nontarget arthropods in the context of grasshopper-control programs, but no work has been done in the Great Basin in Mormon cricket-control areas. This study was instigated in anticipation of the need for extensive control of Orthoptera outbreaks in Utah's west desert during 2005, and it was designed to sample terrestrial and aquatic arthropod communities in both treated and untreated zones. Three areas were sampled: Grouse Creek, Ibapah, and Vernon. High mortality of Mormon cricket eggs in the wet, cool spring of 2005 restricted the need to control Mormon crickets to Grouse Creek. Diflubenzuron was applied (aerial reduced agent-area treatment) in May 2005. Terrestrial and aquatic arthropod communities were sampled before and after application of diflubenzuron in the Grouse Creek area of northwestern Utah in May and June of 2005. In July 2005, U

  17. Ixodes ricinus as vector and reservoir of Borrelia burgdorferi in an urban environment

    Directory of Open Access Journals (Sweden)

    Rajković Dragana V.

    2005-01-01

    Full Text Available As specific arthropods, ticks in urban environments transmit the agents of dangerous contagious diseases endangering human and animal health. They are vectors of numerous infective agents that cause serious diseases of animals such as babesiosis and ehrlichiosis. Tick populations maintain and transmit an increas­ing number of different infective agents. In regard to the human population, they transmit the agents of tick encephalitis, Omsk hemorrhagic disease, Crim-Congo hemorrhagic disease, Kyasa-nur forest fever, ixodid fever, Q fever, Rocky Mountain spotted fever, tularemia, Siberian tick typhus and Lyme disease the last of which according to acarological references has become the dominant zoonosis in over 140 of the world's countries. In urban environments ticks represent problem both for their epidemiological significance and as organisms whose presence disturbs people during their work and rest. In Europe, the two most fre­quent species and Ixodes ricinus and Ixodes persulcatus. Both species have a wide spectrum of hosts.

  18. Is evenness altered by fire in natural assemblages of soil arthropods?

    Science.gov (United States)

    Pitzalis, Monica; Bologna, Marco A.; Luiselli, Luca

    2013-05-01

    We studied evenness and species richness in two assemblages of soil arthropods at six contiguous study plots in Mediterranean ecosystems of central Italy, three of these plots being burnt and three unburnt. We analysed these aspects of community structure by diversity-dominance diagrams comparisons made through analysis of covariance on respective slopes and ordinate intercepts. We observed consistent patterns in both Collembola and Oniscidea assemblages, either in burnt and unburnt plots. Evenness did not change among study plots and across habitats, either before or after fire, whereas species' composition was significantly altered by fire. Results from our study implied that evenness and species diversity are clearly affected in a different and independent way by fire. Hence, it is not acceptable to focus on only the evenness when looking at the effects of controlled fires for environmental management reasons.

  19. Impact of invasive Rosa rugosa on the arthropod fauna of Danish yellow dunes

    DEFF Research Database (Denmark)

    Pernille, Elleriis; Pedersen, Morten Lauge; Toft, Søren

    2015-01-01

    monospecific shrubbery rich in large flowers. We predicted faunal responses according to the changes in resource availability and environmental conditions promoted by this particular invasive plant: increased populations of flower-visiting insects and species of the phytophagous and detritivorous guilds......We compared the arthropod fauna of Rosa rugosa patches to the adjacent native yellow dune vegetation by pitfall trapping in the National Park Thy at the Danish North Sea coast. R. rugosa changes the vegetation from a dune grassland (dominated by Ammophila arenaria) poor in flowering plants to a low...... and diversity and increased dominance in the rose patches, due to reductions among xerotherm species. The results indicate that considerable faunistic impoverishment of thermophilic dune specialist species can be expected in the future if R. rugosa is allowed to continue its invasion across the dune habitat....

  20. Arthropod colonization of land--linking molecules and fossils in oribatid mites (Acari, Oribatida).

    Science.gov (United States)

    Schaefer, Ina; Norton, Roy A; Scheu, Stefan; Maraun, Mark

    2010-10-01

    Terrestrial fossils that document the early colonization of land are scarce for >100 my after the Cambrian explosion. This raises the question whether life on land did not exist or just did not fossilize. With a molecular dating technique, we analyzed the origin of terrestrial chelicerate microarthropods (Acari, Oribatida) which have a fossil record since the Middle Devonian that is exceptional among soil animals. Our results suggest that oribatid mites originated in the Precambrian (571+/-37 mya) and that the radiation of basal groups coincides with the gap in the terrestrial fossil record between the Cambrian explosion and the earliest fossilized records of continental ecosystems. Further, they suggest that the colonization of land started via the interstitial, approximately 150 my earlier than the oldest fossils of terrestrial ecosystems. Overall, the results imply that omnivorous and detritivorous arthropods formed a major component in early terrestrial food webs, thereby facilitating the invasion of terrestrial habitats by later colonizers of higher trophic levels. PMID:20420932

  1. Stable piecewise polynomial vector fields

    Directory of Open Access Journals (Sweden)

    Claudio Pessoa

    2012-09-01

    Full Text Available Let $N={y>0}$ and $S={y<0}$ be the semi-planes of $mathbb{R}^2$ having as common boundary the line $D={y=0}$. Let $X$ and $Y$ be polynomial vector fields defined in $N$ and $S$, respectively, leading to a discontinuous piecewise polynomial vector field $Z=(X,Y$. This work pursues the stability and the transition analysis of solutions of $Z$ between $N$ and $S$, started by Filippov (1988 and Kozlova (1984 and reformulated by Sotomayor-Teixeira (1995 in terms of the regularization method. This method consists in analyzing a one parameter family of continuous vector fields $Z_{epsilon}$, defined by averaging $X$ and $Y$. This family approaches $Z$ when the parameter goes to zero. The results of Sotomayor-Teixeira and Sotomayor-Machado (2002 providing conditions on $(X,Y$ for the regularized vector fields to be structurally stable on planar compact connected regions are extended to discontinuous piecewise polynomial vector fields on $mathbb{R}^2$. Pertinent genericity results for vector fields satisfying the above stability conditions are also extended to the present case. A procedure for the study of discontinuous piecewise vector fields at infinity through a compactification is proposed here.

  2. Chikungunya Virus–Vector Interactions

    Directory of Open Access Journals (Sweden)

    Lark L. Coffey

    2014-11-01

    Full Text Available Chikungunya virus (CHIKV is a mosquito-borne alphavirus that causes chikungunya fever, a severe, debilitating disease that often produces chronic arthralgia. Since 2004, CHIKV has emerged in Africa, Indian Ocean islands, Asia, Europe, and the Americas, causing millions of human infections. Central to understanding CHIKV emergence is knowledge of the natural ecology of transmission and vector infection dynamics. This review presents current understanding of CHIKV infection dynamics in mosquito vectors and its relationship to human disease emergence. The following topics are reviewed: CHIKV infection and vector life history traits including transmission cycles, genetic origins, distribution, emergence and spread, dispersal, vector competence, vector immunity and microbial interactions, and co-infection by CHIKV and other arboviruses. The genetics of vector susceptibility and host range changes, population heterogeneity and selection for the fittest viral genomes, dual host cycling and its impact on CHIKV adaptation, viral bottlenecks and intrahost diversity, and adaptive constraints on CHIKV evolution are also discussed. The potential for CHIKV re-emergence and expansion into new areas and prospects for prevention via vector control are also briefly reviewed.

  3. Field evaluation of picaridin repellents reveals differences in repellent sensitivity between Southeast Asian vectors of malaria and arboviruses.

    Directory of Open Access Journals (Sweden)

    Karel Van Roey

    2014-12-01

    Full Text Available Scaling up of insecticide treated nets has contributed to a substantial malaria decline. However, some malaria vectors, and most arbovirus vectors, bite outdoors and in the early evening. Therefore, topically applied insect repellents may provide crucial additional protection against mosquito-borne pathogens. Among topical repellents, DEET is the most commonly used, followed by others such as picaridin. The protective efficacy of two formulated picaridin repellents against mosquito bites, including arbovirus and malaria vectors, was evaluated in a field study in Cambodia. Over a period of two years, human landing collections were performed on repellent treated persons, with rotation to account for the effect of collection place, time and individual collector. Based on a total of 4996 mosquitoes collected on negative control persons, the overall five hour protection rate was 97.4% [95%CI: 97.1-97.8%], not decreasing over time. Picaridin 20% performed equally well as DEET 20% and better than picaridin 10%. Repellents performed better against Mansonia and Culex spp. as compared to aedines and anophelines. A lower performance was observed against Aedes albopictus as compared to Aedes aegypti, and against Anopheles barbirostris as compared to several vector species. Parity rates were higher in vectors collected on repellent treated person as compared to control persons. As such, field evaluation shows that repellents can provide additional personal protection against early and outdoor biting malaria and arbovirus vectors, with excellent protection up to five hours after application. The heterogeneity in repellent sensitivity between mosquito genera and vector species could however impact the efficacy of repellents in public health programs. Considering its excellent performance and potential to protect against early and outdoor biting vectors, as well as its higher acceptability as compared to DEET, picaridin is an appropriate product to evaluate the

  4. Uncovering Trophic Interactions in Arthropod Predators through DNA Shotgun-Sequencing of Gut Contents.

    Science.gov (United States)

    Paula, Débora P; Linard, Benjamin; Crampton-Platt, Alex; Srivathsan, Amrita; Timmermans, Martijn J T N; Sujii, Edison R; Pires, Carmen S S; Souza, Lucas M; Andow, David A; Vogler, Alfried P

    2016-01-01

    Characterizing trophic networks is fundamental to many questions in ecology, but this typically requires painstaking efforts, especially to identify the diet of small generalist predators. Several attempts have been devoted to develop suitable molecular tools to determine predatory trophic interactions through gut content analysis, and the challenge has been to achieve simultaneously high taxonomic breadth and resolution. General and practical methods are still needed, preferably independent of PCR amplification of barcodes, to recover a broader range of interactions. Here we applied shotgun-sequencing of the DNA from arthropod predator gut contents, extracted from four common coccinellid and dermapteran predators co-occurring in an agroecosystem in Brazil. By matching unassembled reads against six DNA reference databases obtained from public databases and newly assembled mitogenomes, and filtering for high overlap length and identity, we identified prey and other foreign DNA in the predator guts. Good taxonomic breadth and resolution was achieved (93% of prey identified to species or genus), but with low recovery of matching reads. Two to nine trophic interactions were found for these predators, some of which were only inferred by the presence of parasitoids and components of the microbiome known to be associated with aphid prey. Intraguild predation was also found, including among closely related ladybird species. Uncertainty arises from the lack of comprehensive reference databases and reliance on low numbers of matching reads accentuating the risk of false positives. We discuss caveats and some future prospects that could improve the use of direct DNA shotgun-sequencing to characterize arthropod trophic networks. PMID:27622637

  5. Silicon: Potential to Promote Direct and Indirect Effects on Plant Defense Against Arthropod Pests in Agriculture.

    Science.gov (United States)

    Reynolds, Olivia L; Padula, Matthew P; Zeng, Rensen; Gurr, Geoff M

    2016-01-01

    Silicon has generally not been considered essential for plant growth, although it is well recognized that many plants, particularly Poaceae, have substantial plant tissue concentrations of this element. Recently, however, the International Plant Nutrition Institute [IPNI] (2015), Georgia, USA has listed it as a "beneficial substance". This reflects that numerous studies have now established that silicon may alleviate both biotic and abiotic stress. This paper explores the existing knowledge and recent advances in elucidating the role of silicon in plant defense against biotic stress, particularly against arthropod pests in agriculture and attraction of beneficial insects. Silicon confers resistance to herbivores via two described mechanisms: physical and biochemical/molecular. Until recently, studies have mainly centered on two trophic levels; the herbivore and plant. However, several studies now describe tri-trophic effects involving silicon that operate by attracting predators or parasitoids to plants under herbivore attack. Indeed, it has been demonstrated that silicon-treated, arthropod-attacked plants display increased attractiveness to natural enemies, an effect that was reflected in elevated biological control in the field. The reported relationships between soluble silicon and the jasmonic acid (JA) defense pathway, and JA and herbivore-induced plant volatiles (HIPVs) suggest that soluble silicon may enhance the production of HIPVs. Further, it is feasible that silicon uptake may affect protein expression (or modify proteins structurally) so that they can produce additional, or modify, the HIPV profile of plants. Ultimately, understanding silicon under plant ecological, physiological, biochemical, and molecular contexts will assist in fully elucidating the mechanisms behind silicon and plant response to biotic stress at both the bi- and tri-trophic levels. PMID:27379104

  6. The challenge of developing and utilizing transgenic arthropods in the Caribbean

    International Nuclear Information System (INIS)

    To date transgenic arthropods are not being utilized within the Caribbean to control agricultural pests. Bio-control in the region is largely focused on the control of the Pink mealybug since infestations of this pest in any region can result in restrictions being placed on the export of fresh produce into non-infected countries. Other pests controlled by use of conventional bio-control agents include citrus blackfly, citrus leafminer, sugarcane stemborer, coffee berry borer and coconut whitefly. Control of these economic pests is of great importance as crops such as sugarcane, coffee and citrus are major foreign exchange earners in some countries. Applications for the importation, movement and release of these organisms are done through the Pesticide Control Board of the Ministry of Agriculture. Generally guidelines of the FAO code of conduct for the import and release of bio-control agents are used. It is almost inevitable that with the need to increase productivity in the agri-food sector, combined with the need to reduce negative impacts of agri-chemical use, regional research and development efforts will be focused on developing cost effective means of controlling pests common to the region. Such research and development efforts must combine conventional control with genetic engineering methods. Several countries in the Caribbean region are currently examining their regulatory mechanisms to address the trans-boundary movement and environmental release of genetically modified organisms specifically for agricultural purposes. Although most attention has been focused on crop and food regulations some attention will be placed on developing regulations for the use of transgenic arthropods used to control common economic pests. (author)

  7. Efficacy of Controlled Atmosphere Treatments to Manage Arthropod Pests of Dry-Cured Hams.

    Science.gov (United States)

    Hasan, Md Mahbub; Aikins, Michael J; Schilling, Wes; Phillips, Thomas W

    2016-01-01

    Research here explored the use of controlled atmospheres (CA) for managing arthropod pests that infest dry-cured hams. Experiments were conducted with low oxygen (O₂) achieved with low pressure under a vacuum, high carbon dioxide (CO₂), and ozone (O₃). Results showed that both low O₂ and high CO₂ levels required exposures up to 144 h to kill 100% of all stages of red-legged ham beetle, Necrobia rufipes (De Geer) (Coleoptera: Cleridae) and ham mite Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae) at 23 °C. In addition, both low O₂ and high CO₂ had no significant mortality against the ham beetle and ham mites at short exposures ranging from 12 to 48 h. Ham beetles were more tolerant than ham mites to an atmosphere of 75.1% CO₂ and low pressure of 25 mm Hg, which imposed an atmosphere estimated at 0.9% O₂. Both low O₂ and high CO₂ trials indicated that the egg stages of both species were more tolerant than other stages tested, but N. rufipes eggs and pupae were more susceptible than larvae and adults to high concentration ozone treatments. The results indicate that O₃ has potential to control ham beetles and ham mites, particularly at ≈166 ppm in just a 24 h exposure period, but O₃ is known from other work to have poor penetration ability, thus it may be more difficult to apply effectively than low O₂ or high CO₂. would be. CA treatment for arthropod pests of dry-cured hams show promise as components of integrated pest management programs after methyl bromide is no longer available for use. PMID:27598209

  8. Sensitivity and tolerance of Riparian arthropod communities to altered water resources along a drying river.

    Directory of Open Access Journals (Sweden)

    Kevin E McCluney

    Full Text Available BACKGROUND: Rivers around the world are drying with increasing frequency, but little is known about effects on terrestrial animal communities. Previous research along the San Pedro River in southeastern AZ, USA, suggests that changes in the availability of water resources associated with river drying lead to changes in predator abundance, community composition, diversity, and abundance of particular taxa of arthropods, but these observations have not yet been tested manipulatively. METHODS AND RESULTS: In this study, we constructed artificial pools in the stream bed adjacent to a drying section of the San Pedro River and maintained them as the river dried. We compared pitfall trapped arthropods near artificial pools to adjacent control sites where surface waters temporarily dried. Assemblage composition changed differentially at multiple taxonomic levels, resulting in different assemblages at pools than at control sites, with multiple taxa and richness of carabid beetle genera increasing at pools but not at controls that dried. On the other hand, predator biomass, particularly wolf spiders, and diversity of orders and families were consistently higher at control sites that dried. These results suggest an important role for colonization dynamics of pools, as well as the ability of certain taxa, particularly burrowing wolf spiders, to withstand periods of temporary drying. CONCLUSIONS: Overall, we found some agreement between this manipulative study of water resources and a previous analysis of river drying that showed shifts in composition, changes in diversity, and declines in abundance of certain taxa (e.g. carabid beetles. However, colonization dynamics of pools, as well as compensatory strategies of predatory wolf spiders seem to have led to patterns that do not match previous research, with control sites maintaining high diversity, despite drying. Tolerance of river drying by some species may allow persistence of substantial diversity in the

  9. Effect of a botanical acaricide on Ixodes scapularis (Acari: Ixodidae) and nontarget arthropods.

    Science.gov (United States)

    Elias, Susan P; Lubelczyk, Charles B; Rand, Peter W; Staples, Joseph K; St Amand, Theodore W; Stubbs, Constance S; Lacombe, Eleanor H; Smith, Leticia B; Smith, Robert P

    2013-01-01

    We tested the effectiveness of the rosemary oil-based insecticide, Eco-Exempt IC2, to control all stages of Ixodes scapularis (Say) in southern Maine. We selected plots in oak-pine forest where I. scapularis is endemic and recorded the abundance of ticks and nontarget arthropods before and after applications of IC2, bifenthrin (a synthetic pyrethroid), and water (reference treatment). Licensed applicators applied high-pressure spray treatments during the summer nymphal and fall adult seasonal peaks. Both acaricides sprayed during the summer nymphal season reduced nymphal I. scapularis/hour to zero. IC2 was as effective as bifenthrin in controlling nymphs through the rest of the nymphal season and also controlled adult ticks 9 mo postspray compared with 16 mo for bifenthrin, and both acaricides reduced larvae through 14 mo postspray. Both acaricides sprayed during the fall adult season reduced adult I. scapularis/hour to zero; IC2 controlled adult ticks 6 mo postspray compared with 1 yr for bifenthrin. Both fall-applied acaricides controlled nymphs 9 mo postspray and reduced larvae up to 10 mo postspray. Impacts on some nontarget arthropods was assessed. Colleoptera, Hymenoptera, and Collembola declined 1 wk postspray in acaricide-treated plots, and in IC2 plots all numbers rebounded by 20 d postspray. For bees and other flower-visiting insects there were no detectable reductions in nests produced, number emerged from nests, or number of foraging visits to flowering plants in IC2 or bifenthrin plots. IC2 was phytotoxic to the leafy portions of select understory plants that appeared to recover by the next growing season. PMID:23427661

  10. Modern optics in exceptionally preserved eyes of Early Cambrian arthropods from Australia

    Science.gov (United States)

    Lee, Michael S. Y.; Jago, James B.; García-Bellido, Diego C.; Edgecombe, Gregory D.; Gehling, James G.; Paterson, John R.

    2011-06-01

    Despite the status of the eye as an ``organ of extreme perfection'', theory suggests that complex eyes can evolve very rapidly. The fossil record has, until now, been inadequate in providing insight into the early evolution of eyes during the initial radiation of many animal groups known as the Cambrian explosion. This is surprising because Cambrian Burgess-Shale-type deposits are replete with exquisitely preserved animals, especially arthropods, that possess eyes. However, with the exception of biomineralized trilobite eyes, virtually nothing is known about the details of their optical design. Here we report exceptionally preserved fossil eyes from the Early Cambrian (~515 million years ago) Emu Bay Shale of South Australia, revealing that some of the earliest arthropods possessed highly advanced compound eyes, each with over 3,000 large ommatidial lenses and a specialized `bright zone'. These are the oldest non-biomineralized eyes known in such detail, with preservation quality exceeding that found in the Burgess Shale and Chengjiang deposits. Non-biomineralized eyes of similar complexity are otherwise unknown until about 85 million years later. The arrangement and size of the lenses indicate that these eyes belonged to an active predator that was capable of seeing in low light. The eyes are more complex than those known from contemporaneous trilobites and are as advanced as those of many living forms. They provide further evidence that the Cambrian explosion involved rapid innovation in fine-scale anatomy as well as gross morphology, and are consistent with the concept that the development of advanced vision helped to drive this great evolutionary event.

  11. The use of syndromic surveillance to monitor the incidence of arthropod bites requiring healthcare in England, 2000-2013: a retrospective ecological study.

    Science.gov (United States)

    Newitt, S; Elliot, A J; Morbey, R; Durnall, H; Pietzsch, M E; Medlock, J M; Leach, S; Smith, G E

    2016-08-01

    Climate change experts predict the number of nuisance-biting arthropods in England will increase but there is currently no known surveillance system in place to monitor or assess the public health impact of arthropod bites. This retrospective ecological study utilized arthropod bites requiring healthcare from five national real-time syndromic surveillance systems monitoring general practitioner (GP) consultations (in-hours and out-of-hours), emergency department (ED) attendances and telephone calls to remote advice services to determine baseline incidence in England between 2000 and 2013 and to assess the association between arthropod bites and temperature. During summer months (weeks 20-40) we estimated that arthropod bites contribute a weekly median of ~4000 GP consultations, 750 calls to remote advice services, 700 ED and 1300 GP out-of-hours attendances. In all systems, incidence was highest during summer months compared to the rest of the year. Arthropod bites were positively associated with temperature with incidence rate ratios (IRRs) that ranged between systems from 1·03 [95% confidence interval (CI) 1·01-1·06] to 1·14 (95% CI 1·11-1·16). Using syndromic surveillance systems we have established and described baseline incidence of arthropod bites and this can now be monitored routinely in real time to assess the impact of extreme weather events and climate change. PMID:27068133

  12. SURVAI VECTOR DAN RESERVOIR PENYAKIT ZOONOTIK YANG DITULARKAN OLEH ARTHROPODA DI DESA BASI, KECAMATAN DONDO KABUPATEN BUOL — TOLITOLI, SULAWESI TENGAH, INDONESIA

    Directory of Open Access Journals (Sweden)

    Tuti R. Hadi

    2012-09-01

    Full Text Available An ecological survey was conducted in Central Sulawesi to obtain information on the distri­bution of reservoir hosts and vectors of arthropod-borne zoonotic diseases. Serological test were done from human sera collected in the area against arboviral and rickettsial antigens. Three species of Culex mosquitoes known as potential vectors of arbovirosis: Cx. bitaeni-orhynchus, Cx. gelidus and Cx. tritaeniorhynchus, were found in the area surveyed. A known vector of scrub typhus, Leptotrombidium (L. deliensis, was also found in that area. Suspected reservoirs of arthropod-borne zoonosis in the area surveyed were chickens, ducks, cows, horses, monkeys and rats. The prevalence of antibodies against arbovirus group A antigens ( Chikungunya, Getah and Sindbis was 34,06%, 28,5% and 4,39%, against arbovirus group B antigen (Japanese Encepha­litis was 93,4% and none against Rickettsia tsutsugamushi and Rickettsia typhy antigens, out of 91 human sera examined. Antibodies were found in animal sera examined against arbovirus group A and arbovirus group B antigens in a variation of 11,8% — 100%. The prevalence of antibodies against R. tsutsugamushi antigen was 22,7% out of 22 rat sera examined.

  13. A chitin deacetylase-like protein is a predominant constituent of tick peritrophic membrane that influences the persistence of Lyme disease pathogens within the vector.

    Directory of Open Access Journals (Sweden)

    Toru Kariu

    Full Text Available Ixodes scapularis is the specific arthropod vector for a number of globally prevalent infections, including Lyme disease caused by the bacterium Borrelia burgdorferi. A feeding-induced and acellular epithelial barrier, known as the peritrophic membrane (PM is detectable in I. scapularis. However, whether or how the PM influences the persistence of major tick-borne pathogens, such as B. burgdorferi, remains largely unknown. Mass spectrometry-based proteome analyses of isolated PM from fed ticks revealed that the membrane contains a few detectable proteins, including a predominant and immunogenic 60 kDa protein with homology to arthropod chitin deacetylase (CDA, herein termed I. scapularis CDA-like protein or IsCDA. Although IsCDA is primarily expressed in the gut and induced early during tick feeding, its silencing via RNA interference failed to influence either the occurrence of the PM or spirochete persistence, suggesting a redundant role of IsCDA in tick biology and host-pathogen interaction. However, treatment of ticks with antibodies against IsCDA, one of the most predominant protein components of PM, affected B. burgdorferi survival, significantly augmenting pathogen levels within ticks but without influencing the levels of total gut bacteria. These studies suggested a preferential role of tick PM in limiting persistence of B. burgdorferi within the vector. Further understanding of the mechanisms by which vector components contribute to pathogen survival may help the development of new strategies to interfere with the infection.

  14. On the Witt vector Frobenius

    DEFF Research Database (Denmark)

    Davis, Christopher James; Kedlaya, Kiran

    2014-01-01

    We study the kernel and cokernel of the Frobenius map on the p-typical Witt vectors of a commutative ring, not necessarily of characteristic p. We give many equivalent conditions to surjectivity of the Frobenius map on both finite and infinite length Witt vectors. In particular, surjectivity...... on finite Witt vectors turns out to be stable under certain integral extensions; this provides a clean formulation of a strong generalization of Faltings’s almost purity theorem from p-adic Hodge theory, incorporating recent improvements by Kedlaya–Liu and by Scholze....

  15. Vector control of induction machines

    CERN Document Server

    Robyns, Benoit

    2012-01-01

    After a brief introduction to the main law of physics and fundamental concepts inherent in electromechanical conversion, ""Vector Control of Induction Machines"" introduces the standard mathematical models for induction machines - whichever rotor technology is used - as well as several squirrel-cage induction machine vector-control strategies. The use of causal ordering graphs allows systematization of the design stage, as well as standardization of the structure of control devices. ""Vector Control of Induction Machines"" suggests a unique approach aimed at reducing parameter sensitivity for

  16. Isotope and radiation research on animal diseases and their vectors. Proceedings series

    Energy Technology Data Exchange (ETDEWEB)

    1980-01-01

    To solve the world-wide problems of famine, malnutrition and environmental pollution it is imperative that all techniques and resources for the protection of animals and plants be mobilized. N'gana (animal trypansomiasis) alone profoundly affects the socio-economic development of Africa. Its vector, the tsetse fly, is widespread and prevents agricultural development over much of this continent of 7 million square kilometres. To discuss these problems the symposium was convened by the International Atomic Energy Agency from 7 to 11 May 1979. It was an integral part of the IAEA and FAO's effort to promote a greater awareness of the actual and potential application of nuclear techniques in the resolution of problems in the control of arthropod vectors of animal diseases and of animal pathogens, and in pesticide management. A total of 58 participants from 19 countries attended, and 37 papers were presented, which covered a variety of topics, including the sterile insect technique as applied to tsetse flies. Several papers were presented covering its various aspects such as mass rearing, sterility induction, ecology, behavior and computer modelling. Other topics emphasized were pathogenesis and immunology of vector-borne diseases such as trypanosomiasis, anaplasmosis, babesiosis and leishmaniasis. Also included were presentations of insect repellents and the biotransformation and degradation of labelled pesticides.

  17. All optical vector magnetometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase I research project will investigate a novel method of operating an atomic magnetometer to simultaneously measure total magnetic fields and vector...

  18. Introduction to matrices and vectors

    CERN Document Server

    Schwartz, Jacob T

    2001-01-01

    In this concise undergraduate text, the first three chapters present the basics of matrices - in later chapters the author shows how to use vectors and matrices to solve systems of linear equations. 1961 edition.

  19. Acoustic vector sensor signal processing

    Institute of Scientific and Technical Information of China (English)

    SUN Guiqing; LI Qihu; ZHANG Bin

    2006-01-01

    Acoustic vector sensor simultaneously, colocately and directly measures orthogonal components of particle velocity as well as pressure at single point in acoustic field so that is possible to improve performance of traditional underwater acoustic measurement devices or detection systems and extends new ideas for solving practical underwater acoustic engineering problems. Although acoustic vector sensor history of appearing in underwater acoustic area is no long, but with huge and potential military demands, acoustic vector sensor has strong development trend in last decade, it is evolving into a one of important underwater acoustic technology. Under this background, we try to review recent progress in study on acoustic vector sensor signal processing, such as signal detection, DOA estimation, beamforming, and so on.

  20. Transcriptional Silencing of Retroviral Vectors

    DEFF Research Database (Denmark)

    Lund, Anders Henrik; Duch, M.; Pedersen, F.S.

    1996-01-01

    . Extinction of long-term vector expression has been observed after implantation of transduced hematopoietic cells as well as fibroblasts, myoblasts and hepatocytes. Here we review the influence of vector structure, integration site and cell type on transcriptional silencing. While down-regulation of proviral...... transcription is known from a number of cellular and animal models, major insight has been gained from studies in the germ line and embryonal cells of the mouse. Key elements for the transfer and expression of retroviral vectors, such as the viral transcriptional enhancer and the binding site for the t......RNA primer for reverse transcription may have a major influence on transcriptional silencing. Alterations of these elements of the vector backbone as well as the use of internal promoter elements from housekeeping genes may contribute to reduce transcriptional silencing. The use of cell culture and animal...

  1. Unsupervised learning of binary vectors

    Science.gov (United States)

    Copelli Lopes da Silva, Mauro

    In this thesis, unsupervised learning of binary vectors from data is studied using methods from Statistical Mechanics of disordered systems. In the model, data vectors are distributed according to a single symmetry-breaking direction. The aim of unsupervised learning is to provide a good approximation to this direction. The difference with respect to previous studies is the knowledge that this preferential direction has binary components. It is shown that sampling from the posterior distribution (Gibbs learning) leads, for general smooth distributions, to an exponentially fast approach to perfect learning in the asymptotic limit of large number of examples. If the distribution is non-smooth, then first order phase transitions to perfect learning are expected. In the limit of poor performance, a second order phase transition ("retarded learning") is predicted to occur if the data distribution is not biased. Using concepts from Bayesian inference, the center of mass of the Gibbs ensemble is shown to have maximal average (Bayes-optimal) performance. This upper bound for continuous vectors is extended to a discrete space, resulting in the clipped center of mass of the Gibbs ensemble having maximal average performance among the binary vectors. To calculate the performance of this best binary vector, the geometric properties of the center of mass of binary vectors are studied. The surprising result is found that the center of mass of infinite binary vectors which obey some simple constraints, is again a binary vector. When disorder is taken into account in the calculation, however, a vector with continuous components is obtained. The performance of the best binary vector is calculated and shown to always lie above that of Gibbs learning and below the Bayes-optimal performance. Making use of a variational approach under the replica symmetric ansatz, an optimal potential is constructed in the limits of zero temperature and mutual overlap 1. Minimization of this potential

  2. Saliva proteins of vector Culicoides modify structure and infectivity of bluetongue virus particles.

    Directory of Open Access Journals (Sweden)

    Karin E Darpel

    Full Text Available Bluetongue virus (BTV and epizootic haemorrhagic disease virus (EHDV are related orbiviruses, transmitted between their ruminant hosts primarily by certain haematophagous midge vectors (Culicoides spp.. The larger of the BTV outer-capsid proteins, 'VP2', can be cleaved by proteases (including trypsin or chymotrypsin, forming infectious subviral particles (ISVP which have enhanced infectivity for adult Culicoides, or KC cells (a cell-line derived from C. sonorensis. We demonstrate that VP2 present on purified virus particles from 3 different BTV strains can also be cleaved by treatment with saliva from adult Culicoides. The saliva proteins from C. sonorensis (a competent BTV vector, cleaved BTV-VP2 more efficiently than those from C. nubeculosus (a less competent/non-vector species. Electrophoresis and mass spectrometry identified a trypsin-like protease in C. sonorensis saliva, which was significantly reduced or absent from C. nubeculosus saliva. Incubating purified BTV-1 with C. sonorensis saliva proteins also increased their infectivity for KC cells ∼10 fold, while infectivity for BHK cells was reduced by 2-6 fold. Treatment of an 'eastern' strain of EHDV-2 with saliva proteins of either C. sonorensis or C. nubeculosus cleaved VP2, but a 'western' strain of EHDV-2 remained unmodified. These results indicate that temperature, strain of virus and protein composition of Culicoides saliva (particularly its protease content which is dependent upon vector species, can all play a significant role in the efficiency of VP2 cleavage, influencing virus infectivity. Saliva of several other arthropod species has previously been shown to increase transmission, infectivity and virulence of certain arboviruses, by modulating and/or suppressing the mammalian immune response. The findings presented here, however, demonstrate a novel mechanism by which proteases in Culicoides saliva can also directly modify the orbivirus particle structure, leading to

  3. Decays of the vector glueball

    CERN Document Server

    Giacosa, Francesco; Janowski, Stanislaus

    2016-01-01

    We calculate two- and three-body decays of the (lightest) vector glueball into (pseudo)scalar, (axial-)vector, as well as pseudovector and excited vector mesons. By setting the mass of this yet hypothetical vector glueball to 3.8 GeV as predicted by Lattice QCD, many branching ratios can be computed and represent a parameter-free prediction of our approach. We find that the decay mode $\\omega\\pi\\pi$ should be one of the largest (both through the decay chain $\\mathcal{O}\\rightarrow b_{1}\\pi\\rightarrow$ $\\omega\\pi\\pi$ and through the direct coupling $\\mathcal{O}\\rightarrow\\omega\\pi\\pi$)$.$ Similarly, the (direct and indirect) decay into $\\pi KK^{\\ast}(892)$ is sizable. Moreover, the decays into $\\rho\\pi$ and $K^{\\ast}(892)K$ are, although subleading, possible and could play a role in explaining the $\\rho\\pi$ puzzle of the charmonium state $\\psi(2S)$ thank to a (small) mixing with the vector glueball. The vector glueball can be directly formed at the ongoing BESIII experiment as well as at the future PANDA exper...

  4. Axisymmetric Coanda-assisted vectoring

    Energy Technology Data Exchange (ETDEWEB)

    Allen, Dustin; Smith, Barton L. [Utah State University, Mechanical and Aerospace Engineering, Logan, UT (United States)

    2009-01-15

    An experimental demonstration of a jet vectoring technique used in our novel spray method called Coanda-assisted Spray Manipulation (CSM) is presented. CSM makes use of the Coanda effect on axisymmetric geometries through the interaction of two jets: a primary jet and a control jet. The primary jet has larger volume flow rate but generally a smaller momentum flux than the control jet. The primary jet flows through the center of a rounded collar. The control jet is parallel to the primary and is adjacent to the convex collar. The Reynolds number range for the primary jet at the exit plane was between 20,000 and 80,000. The flow was in the incompressible Mach number range (Mach<0.3). The control jet attaches to the convex wall and vectors according to known Coanda effect principles, entraining and vectoring the primary jet, resulting in controllable r-{theta} directional spraying. Several annular control slots and collar radii were tested over a range of momentum flux ratios to determine the effects of these variables on the vectored jet angle and spreading. Two and Three-component Particle Image Velocimetry systems were used to determine the vectoring angle and the profile of the combined jet in each experiment. The experiments show that the control slot and expansion radius, along with the momentum ratios of the two jets predominantly affected the vectoring angle and profile of the combined jets. (orig.)

  5. Vectoring of parallel synthetic jets

    Science.gov (United States)

    Berk, Tim; Ganapathisubramani, Bharathram; Gomit, Guillaume

    2015-11-01

    A pair of parallel synthetic jets can be vectored by applying a phase difference between the two driving signals. The resulting jet can be merged or bifurcated and either vectored towards the actuator leading in phase or the actuator lagging in phase. In the present study, the influence of phase difference and Strouhal number on the vectoring behaviour is examined experimentally. Phase-locked vorticity fields, measured using Particle Image Velocimetry (PIV), are used to track vortex pairs. The physical mechanisms that explain the diversity in vectoring behaviour are observed based on the vortex trajectories. For a fixed phase difference, the vectoring behaviour is shown to be primarily influenced by pinch-off time of vortex rings generated by the synthetic jets. Beyond a certain formation number, the pinch-off timescale becomes invariant. In this region, the vectoring behaviour is determined by the distance between subsequent vortex rings. We acknowledge the financial support from the European Research Council (ERC grant agreement no. 277472).

  6. Black holes with vector hair

    Science.gov (United States)

    Fan, Zhong-Ying

    2016-09-01

    In this paper, we consider Einstein gravity coupled to a vector field, either minimally or non-minimally, together with a vector potential of the type V = 2{Λ}_0+1/2{m}^2{A}^2 + {γ}_4{A}^4 . For a simpler non-minimally coupled theory with Λ0 = m = γ4 = 0, we obtain both extremal and non-extremal black hole solutions that are asymptotic to Minkowski space-times. We study the global properties of the solutions and derive the first law of thermodynamics using Wald formalism. We find that the thermodynamical first law of the extremal black holes is modified by a one form associated with the vector field. In particular, due to the existence of the non-minimal coupling, the vector forms thermodynamic conjugates with the graviton mode and partly contributes to the one form modifying the first law. For a minimally coupled theory with Λ0 ≠ 0, we also obtain one class of asymptotically flat extremal black hole solutions in general dimensions. This is possible because the parameters ( m 2 , γ4) take certain values such that V = 0. In particular, we find that the vector also forms thermodynamic conjugates with the graviton mode and contributes to the corresponding first law, although the non-minimal coupling has been turned off. Thus all the extremal black hole solutions that we obtain provide highly non-trivial examples how the first law of thermodynamics can be modified by a either minimally or non-minimally coupled vector field. We also study Gauss-Bonnet gravity non-minimally coupled to a vector and obtain asymptotically flat black holes and Lifshitz black holes.

  7. Arthropod Distribution and Habitat, Published in 2010, 1:24000 (1in=2000ft) scale, GaDNR/Wildlife Resources Division.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Arthropod Distribution and Habitat dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Observation information as of 2010....

  8. The Duality on Vector Optimization Problems

    Institute of Scientific and Technical Information of China (English)

    HUANG Long-guang

    2012-01-01

    Duality framework on vector optimization problems in a locally convex topological vector space are established by using scalarization with a cone-strongly increasing function.The dualities for the scalar convex composed optimization problems and for general vector optimization problems are studied.A general approach for studying duality in vector optimization problems is presented.

  9. The biological control of disease vectors.

    Science.gov (United States)

    Okamoto, Kenichi W; Amarasekare, Priyanga

    2012-09-21

    Vector-borne diseases are common in nature and can have a large impact on humans, livestock and crops. Biological control of vectors using natural enemies or competitors can reduce vector density and hence disease transmission. However, the indirect interactions inherent in host-vector disease systems make it difficult to use traditional pest control theory to guide biological control of disease vectors. This necessitates a conceptual framework that explicitly considers a range of indirect interactions between the host-vector disease system and the vector's biological control agent. Here we conduct a comparative analysis of the efficacy of different types of biological control agents in controlling vector-borne diseases. We report three key findings. First, highly efficient predators and parasitoids of the vector prove to be effective biological control agents, but highly virulent pathogens of the vector also require a high transmission rate to be effective. Second, biocontrol agents can successfully reduce long-term host disease incidence even though they may fail to reduce long-term vector densities. Third, inundating a host-vector disease system with a natural enemy of the vector has little or no effect on reducing disease incidence, but inundating the system with a competitor of the vector has a large effect on reducing disease incidence. The comparative framework yields predictions that are useful in developing biological control strategies for vector-borne diseases. We discuss how these predictions can inform ongoing biological control efforts for host-vector disease systems.

  10. A NOTE ON VECTOR CASCADE ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    Qiu-hui Chen; Jin-zhao Liu; Wen-sheng Zhang

    2002-01-01

    The focus of this paper is on the relationship between accuracy of multivariate refinable vector and vector cascade algorithm. We show that, if the vector cascade algorithm (1.5) with isotropic dilation converges to a vector-valued function with regularity, then the initial function must satisfy the Strang-Fix conditions.

  11. Ant-App-DB: a smart solution for monitoring arthropods activities, experimental data management and solar calculations without GPS in behavioral field studies

    OpenAIRE

    Zeeshan Ahmed; Saman Zeeshan; Pauline Fleischmann; Wolfgang Rössler; Thomas Dandekar

    2015-01-01

    Field studies on arthropod ecology and behaviour require simple and robust monitoring tools, preferably with direct access to an integrated database. We have developed and here present a database tool allowing smart-phone based monitoring of arthropods. This smart phone application provides an easy solution to collect, manage and process the data in the field which has been a very difficult task for field biologists using traditional methods. To monitor our example species, the desert ant Cat...

  12. Adaptations and Predispositions of Different Middle European Arthropod Taxa (Collembola, Araneae, Chilopoda, Diplopoda) to Flooding and Drought Conditions.

    Science.gov (United States)

    Marx, Michael Thomas; Guhmann, Patrick; Decker, Peter

    2012-01-01

    Floodplain forests and wetlands are amongst the most diverse and species rich habitats on earth. Arthropods are a key group for the high diversity pattern of these landscapes, due to the fact that the change between flooding and drought causes in different life cycles and in a variety of adaptations in the different taxa. The floodplain forests and wetlands of Central Amazonia are well investigated and over the last 50 years many adaptations of several hexapod, myriapod and arachnid orders were described. In contrast to Amazonia the Middle European floodplains were less investigated concerning the adaptations of arthropods to flood and drought conditions. This review summarizes the adaptations and predispositions of springtails, web spiders, millipedes and centipedes to the changeable flood and drought conditions of Middle European floodplain forests and wetlands. Furthermore the impact of regional climate change predictions like increasing aperiodic summer floods and the decrease of typical winter and spring floods are discussed in this article. PMID:26487164

  13. Temperature-size responses match latitudinal-size clines in arthropods, revealing critical differences between aquatic and terrestrial species

    DEFF Research Database (Denmark)

    Horne, C.R.; Hirst, Andrew G.; Atkinson, D.

    2015-01-01

    of these gradients to date, and find that their direction and magnitude co-vary among 12 arthropod orders (r2 = 0.72). Body size in aquatic species generally reduces with both warming and decreasing latitude, whereas terrestrial species have much reduced and even opposite gradients. These patterns support...... the prediction that oxygen limitation is a major controlling factor in water, but not in air. Furthermore, voltinism explains much of the variation in T-S and L-S patterns in terrestrial but not aquatic species. While body size decreases with warming and with decreasing latitude in multivoltine terrestrial...... arthropods, size increases on average in univoltine species, consistent with predictions from size vs. season-length trade-offs...

  14. Adaptations and Predispositions of Different Middle European Arthropod Taxa (Collembola, Araneae, Chilopoda, Diplopoda to Flooding and Drought Conditions

    Directory of Open Access Journals (Sweden)

    Patrick Guhmann

    2012-10-01

    Full Text Available Floodplain forests and wetlands are amongst the most diverse and species rich habitats on earth. Arthropods are a key group for the high diversity pattern of these landscapes, due to the fact that the change between flooding and drought causes in different life cycles and in a variety of adaptations in the different taxa. The floodplain forests and wetlands of Central Amazonia are well investigated and over the last 50 years many adaptations of several hexapod, myriapod and arachnid orders were described. In contrast to Amazonia the Middle European floodplains were less investigated concerning the adaptations of arthropods to flood and drought conditions. This review summarizes the adaptations and predispositions of springtails, web spiders, millipedes and centipedes to the changeable flood and drought conditions of Middle European floodplain forests and wetlands. Furthermore the impact of regional climate change predictions like increasing aperiodic summer floods and the decrease of typical winter and spring floods are discussed in this article.

  15. Evolutionary origin and genomic organisation of runt-domain containing genes in arthropods

    Directory of Open Access Journals (Sweden)

    Smith James M

    2008-11-01

    Full Text Available Abstract Background Gene clusters, such as the Hox gene cluster, are known to have critical roles in development. In eukaryotes gene clusters arise primarily by tandem gene duplication and divergence. Genes within a cluster are often co-regulated, providing selective pressure to maintain the genome organisation, and this co-regulation can result in temporal or spatial co-linearity of gene expression. It has been previously noted that in Drosophila melanogaster, three of the four runt-domain (RD containing genes are found in a relatively tight cluster on chromosome 1, raising the possibility of a putative functional RD gene cluster in D. melanogaster. Results To investigate the possibility of such a gene cluster, orthologues of the Drosophila melanogaster RD genes were identified in several endopterygotan insects, two exopterygotan insects and two non-insect arthropods. In all insect species four RD genes were identified and orthology was assigned to the Drosophila sequences by phylogenetic analyses. Although four RD genes were found in the crustacean D. pulex, orthology could not be assigned to the insect sequences, indicating independent gene duplications from a single ancestor following the split of the hexapod lineage from the crustacean lineage. In insects, two chromosomal arrangements of these genes was observed; the first a semi-dispersed cluster, such as in Drosophila, where lozenge is separated from the core cluster of three RD genes often by megabases of DNA. The second arrangement was a tight cluster of the four RD genes, such as in Apis mellifera. This genomic organisation, particularly of the three core RD genes, raises the possibility of shared regulatory elements. In situ hybridisation of embryonic expression of the four RD genes in Drosophila melanogaster and the honeybee A. mellifera shows no evidence for either spatial or temporal co-linearity of expression during embryogenesis. Conclusion All fully sequenced insect genomes

  16. Mechanical implications of the arthropod exoskeleton microstructures and the mechanical behavior of the bioinspired composites

    Science.gov (United States)

    Cheng, Liang

    Many biological materials possess complicated hierarchical and multiscale structures, after millions of years of evolution. Most of them also demonstrate outstanding mechanical properties, along with multi-functionality. Arthropod is the most widely distributed and the largest phylum of animals in the planet. Their exoskeletons are well-known for excellent mechanical performance and versatility, and consequently emerge among the best sources to study and uncover the mystery of nature in devising its own material systems. This work first investigated the microstructures of the exoskeletons from selected arthropods, including Homarus Americanus, Callinectes sapidus and Popillia japonica, which exhibit highly complex but interesting hierarchical structures. Exoskeletons are chitin-protein based material systems organized into horizontally well-defined multi-region and multi-layer patterns, with elaborate structures interweaving in the vertical direction. Using SEM (Scanning Electron Microscope) and TEM (Transmission Electron Microscope), the characteristic and distinctive structural features of the exoskeletons were revealed for all the species investigated. In particular, distinct patterns (e.g., stacking sequence of multiple layers) were identified in each region of exoskeletons studied. For example, the "helicoidal structure" is characterized by a stacking sequence in which layers are continuously and unidirectionally rotating a small angle with respect to their adjacent layers. Important mechanical implications of those unique structural features were subsequently evaluated and compared using mechanics-based modeling and analysis, as well as numerical simulation. After the structure-property-function relationship of the investigated biomaterial systems was established, attempts were made to reveal and extract the design strategies employed by nature in designing its own materials and structures. One of the most predominant structural patterns observed in the

  17. Bt crop effects on functional guilds of non-target arthropods: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    L LaReesa Wolfenbarger

    Full Text Available BACKGROUND: Uncertainty persists over the environmental effects of genetically-engineered crops that produce the insecticidal Cry proteins of Bacillus thuringiensis (Bt. We performed meta-analyses on a modified public database to synthesize current knowledge about the effects of Bt cotton, maize and potato on the abundance and interactions of arthropod non-target functional guilds. METHODOLOGY/PRINCIPAL FINDINGS: We compared the abundance of predators, parasitoids, omnivores, detritivores and herbivores under scenarios in which neither, only the non-Bt crops, or both Bt and non-Bt crops received insecticide treatments. Predators were less abundant in Bt cotton compared to unsprayed non-Bt controls. As expected, fewer specialist parasitoids of the target pest occurred in Bt maize fields compared to unsprayed non-Bt controls, but no significant reduction was detected for other parasitoids. Numbers of predators and herbivores were higher in Bt crops compared to sprayed non-Bt controls, and type of insecticide influenced the magnitude of the difference. Omnivores and detritivores were more abundant in insecticide-treated controls and for the latter guild this was associated with reductions of their predators in sprayed non-Bt maize. No differences in abundance were found when both Bt and non-Bt crops were sprayed. Predator-to-prey ratios were unchanged by either Bt crops or the use of insecticides; ratios were higher in Bt maize relative to the sprayed non-Bt control. CONCLUSIONS/SIGNIFICANCE: Overall, we find no uniform effects of Bt cotton, maize and potato on the functional guilds of non-target arthropods. Use of and type of insecticides influenced the magnitude and direction of effects; insecticde effects were much larger than those of Bt crops. These meta-analyses underscore the importance of using controls not only to isolate the effects of a Bt crop per se but also to reflect the replacement of existing agricultural practices. Results will

  18. Implementing Bayesian Vector Autoregressions Implementing Bayesian Vector Autoregressions

    Directory of Open Access Journals (Sweden)

    Richard M. Todd

    1988-03-01

    Full Text Available Implementing Bayesian Vector Autoregressions This paper discusses how the Bayesian approach can be used to construct a type of multivariate forecasting model known as a Bayesian vector autoregression (BVAR. In doing so, we mainly explain Doan, Littermann, and Sims (1984 propositions on how to estimate a BVAR based on a certain family of prior probability distributions. indexed by a fairly small set of hyperparameters. There is also a discussion on how to specify a BVAR and set up a BVAR database. A 4-variable model is used to iliustrate the BVAR approach.

  19. Vector Encoding in Biochemical Networks

    Science.gov (United States)

    Potter, Garrett; Sun, Bo

    Encoding of environmental cues via biochemical signaling pathways is of vital importance in the transmission of information for cells in a network. The current literature assumes a single cell state is used to encode information, however, recent research suggests the optimal strategy utilizes a vector of cell states sampled at various time points. To elucidate the optimal sampling strategy for vector encoding, we take an information theoretic approach and determine the mutual information of the calcium signaling dynamics obtained from fibroblast cells perturbed with different concentrations of ATP. Specifically, we analyze the sampling strategies under the cases of fixed and non-fixed vector dimension as well as the efficiency of these strategies. Our results show that sampling with greater frequency is optimal in the case of non-fixed vector dimension but that, in general, a lower sampling frequency is best from both a fixed vector dimension and efficiency standpoint. Further, we find the use of a simple modified Ornstein-Uhlenbeck process as a model qualitatively captures many of our experimental results suggesting that sampling in biochemical networks is based on a few basic components.

  20. Axisymmetric Coanda-assisted vectoring

    Science.gov (United States)

    Allen, Dustin; Smith, Barton L.

    2009-01-01

    An experimental demonstration of a jet vectoring technique used in our novel spray method called Coanda-assisted Spray Manipulation (CSM) is presented. CSM makes use of the Coanda effect on axisymmetric geometries through the interaction of two jets: a primary jet and a control jet. The primary jet has larger volume flow rate but generally a smaller momentum flux than the control jet. The primary jet flows through the center of a rounded collar. The control jet is parallel to the primary and is adjacent to the convex collar. The Reynolds number range for the primary jet at the exit plane was between 20,000 and 80,000. The flow was in the incompressible Mach number range (Mach Coanda effect principles, entraining and vectoring the primary jet, resulting in controllable r - θ directional spraying. Several annular control slots and collar radii were tested over a range of momentum flux ratios to determine the effects of these variables on the vectored jet angle and spreading. Two and Three-component Particle Image Velocimetry systems were used to determine the vectoring angle and the profile of the combined jet in each experiment. The experiments show that the control slot and expansion radius, along with the momentum ratios of the two jets predominantly affected the vectoring angle and profile of the combined jets.

  1. A generalized nonlocal vector calculus

    Science.gov (United States)

    Alali, Bacim; Liu, Kuo; Gunzburger, Max

    2015-10-01

    A nonlocal vector calculus was introduced in Du et al. (Math Model Meth Appl Sci 23:493-540, 2013) that has proved useful for the analysis of the peridynamics model of nonlocal mechanics and nonlocal diffusion models. A formulation is developed that provides a more general setting for the nonlocal vector calculus that is independent of particular nonlocal models. It is shown that general nonlocal calculus operators are integral operators with specific integral kernels. General nonlocal calculus properties are developed, including nonlocal integration by parts formula and Green's identities. The nonlocal vector calculus introduced in Du et al. (Math Model Meth Appl Sci 23:493-540, 2013) is shown to be recoverable from the general formulation as a special example. This special nonlocal vector calculus is used to reformulate the peridynamics equation of motion in terms of the nonlocal gradient operator and its adjoint. A new example of nonlocal vector calculus operators is introduced, which shows the potential use of the general formulation for general nonlocal models.

  2. Ensemble Dynamics and Bred Vectors

    CERN Document Server

    Balci, Nusret; Restrepo, Juan M; Sell, George R

    2011-01-01

    We introduce the new concept of an EBV to assess the sensitivity of model outputs to changes in initial conditions for weather forecasting. The new algorithm, which we call the "Ensemble Bred Vector" or EBV, is based on collective dynamics in essential ways. By construction, the EBV algorithm produces one or more dominant vectors. We investigate the performance of EBV, comparing it to the BV algorithm as well as the finite-time Lyapunov Vectors. We give a theoretical justification to the observed fact that the vectors produced by BV, EBV, and the finite-time Lyapunov vectors are similar for small amplitudes. Numerical comparisons of BV and EBV for the 3-equation Lorenz model and for a forced, dissipative partial differential equation of Cahn-Hilliard type that arises in modeling the thermohaline circulation, demonstrate that the EBV yields a size-ordered description of the perturbation field, and is more robust than the BV in the higher nonlinear regime. The EBV yields insight into the fractal structure of th...

  3. An aglaspidid arthropod from the Upper Ordovician of Morocco with remarks on the affinities and limitations of Aglaspidida

    OpenAIRE

    Roy, P

    2006-01-01

    A new aglaspidid arthropod, Chlupacaris dubia gen. et sp. nov., is described from the Pusgillian (lower Ashgill, Upper Ordovician) Upper Tiouririne Formation near Erfoud, southeastern Morocco. Although disarticulated, careful documenting of the tergites allows a reconstruction of the exoskeleton to be made. Although somewhat trilobite-like in appearance, the lack of facial sutures, a well-defined axis with articulating half-rings and a pygidium clearly prove Chlupacaris gen. nov. is not a tri...

  4. Low cost venom extractor based on Arduino(®) board for electrical venom extraction from arthropods and other small animals.

    Science.gov (United States)

    Besson, Thomas; Debayle, Delphine; Diochot, Sylvie; Salinas, Miguel; Lingueglia, Eric

    2016-08-01

    Extracting venom from small species is usually challenging. We describe here an affordable and versatile electrical venom extractor based on the Arduino(®) Mega 2560 Board, which is designed to extract venom from arthropods and other small animals. The device includes fine tuning of stimulation time and voltage. It was used to collect venom without apparent deleterious effects, and characterized for the first time the venom of Zoropsis spinimana, a common spider in French Mediterranean regions. PMID:27158113

  5. The Cultivation of Bt Corn Producing Cry1Ac Toxins Does Not Adversely Affect Non-Target Arthropods

    OpenAIRE

    Yanyan Guo; Yanjie Feng; Yang Ge; Guillaume Tetreau; Xiaowen Chen; Xuehui Dong; Wangpeng Shi

    2014-01-01

    Transgenic corn producing Cry1Ac toxins from Bacillus thuringiensis (Bt) provides effective control of Asian corn borer, Ostrinia furnacalis (Guenée), and thus reduces insecticide applications. However, whether Bt corn exerts undesirable effects on non-target arthropods (NTAs) is still controversial. We conducted a 2-yr study in Shangzhuang Agricultural Experiment Station to assess the potential impact of Bt corn on field population density, biodiversity, community composition and structure o...

  6. Factors Affecting the Abundance of Leaf-Litter Arthropods in Unburned and Thrice-Burned Seasonally-Dry Amazonian Forests

    OpenAIRE

    Silveira, Juliana M.; Barlow, Jos; Louzada, Julio; Moutinho, Paulo

    2010-01-01

    Fire is frequently used as a land management tool for cattle ranching and annual crops in the Amazon. However, these maintenance fires often escape into surrounding forests, with potentially severe impacts for forest biodiversity. We examined the effect of experimental fires on leaf-litter arthropod abundance in a seasonally-dry forest in the Brazilian Amazon. The study plots (50 ha each) included a thrice-burned forest and an unburned control forest. Pitfall-trap samples were collected at 16...

  7. Low cost venom extractor based on Arduino(®) board for electrical venom extraction from arthropods and other small animals.

    Science.gov (United States)

    Besson, Thomas; Debayle, Delphine; Diochot, Sylvie; Salinas, Miguel; Lingueglia, Eric

    2016-08-01

    Extracting venom from small species is usually challenging. We describe here an affordable and versatile electrical venom extractor based on the Arduino(®) Mega 2560 Board, which is designed to extract venom from arthropods and other small animals. The device includes fine tuning of stimulation time and voltage. It was used to collect venom without apparent deleterious effects, and characterized for the first time the venom of Zoropsis spinimana, a common spider in French Mediterranean regions.

  8. Assessing the comparative risk of plant protection products to honey bees, non-target arthropods and non-Apis bees

    OpenAIRE

    Miles, Mark J.; Alix, Anne

    2012-01-01

    Background: In the European Union the placing of pesticides on the market requires as a prerequisite that a risk assessment demonstrates low risks to human health and the environment, among which includes pollinators. Currently risks are evaluated for honey bees and for non-target arthropods (NTA) of cultivated ecosystems. The actual protection of pollinators other than the honey bees, as for example for non-Apis bees, in relation to these risk assessments has recently been questioned and req...

  9. The effects of flooding disturbance on the distribution and behaviour of riparian arthropods along a lowland gravel river

    OpenAIRE

    Lambeets, Kevin

    2009-01-01

    This Ph.D.-thesis aimed to address which environmental factors influence the assemblage structure of mobile, riparian arthropods along spatially structured river banks of a rain-fed, lowland gravel river, the Common Meuse. As riverine ecosystems are basically non-equilibrium, dynamic ecosystems, mainly flow regimes and flood pulse characteristics are expected to shape both the distribution and behaviour of its inhabitants. The river banks along the Common Meuse are (in)frequently disturbed by...

  10. Entrapment Bias of Arthropods in Miocene Amber Revealed by Trapping Experiments in a Tropical Forest in Chiapas, Mexico

    OpenAIRE

    Solórzano Kraemer, Mónica M.; Kraemer, Atahualpa S.; Stebner, Frauke; Bickel, Daniel J.; Rust, Jes

    2015-01-01

    All entomological traps have a capturing bias, and amber, viewed as a trap, is no exception. Thus the fauna trapped in amber does not represent the total existing fauna of the former amber forest, rather the fauna living in and around the resin producing tree. In this paper we compare arthropods from a forest very similar to the reconstruction of the Miocene Mexican amber forest, and determine the bias of different trapping methods, including amber. We also show, using cluster analyses, measu...

  11. Spatial and temporal distribution of litter arthropods in different vegetation covers of Porto Santo Island (Madeira Archipelago, Portugal)

    OpenAIRE

    Antunes, S. C.; Pereira, R.; Sousa, J.P.; Santos, M.C.; F. Gonçalves

    2008-01-01

    The main objective of this study is to assess the soil diversity and temporal and spatial distribution of litter macro-arthropods, captured with pitfall traps, on different vegetation covers from Porto Santo Island (Portugal) with different soil physical and chemical characteristics. The PCA clearly separated sampling areas geographically more exposed to winds and solar radiation, from the others that were not. In this analysis, seasons seemed to have no influence on this distribution. Non-ex...

  12. Entrapment bias of arthropods in Miocene amber revealed by trapping experiments in a tropical forest in Chiapas, Mexico.

    Directory of Open Access Journals (Sweden)

    Mónica M Solórzano Kraemer

    Full Text Available All entomological traps have a capturing bias, and amber, viewed as a trap, is no exception. Thus the fauna trapped in amber does not represent the total existing fauna of the former amber forest, rather the fauna living in and around the resin producing tree. In this paper we compare arthropods from a forest very similar to the reconstruction of the Miocene Mexican amber forest, and determine the bias of different trapping methods, including amber. We also show, using cluster analyses, measurements of the trapped arthropods, and guild distribution, that the amber trap is a complex entomological trap not comparable with a single artificial trap. At the order level, the most similar trap to amber is the sticky trap. However, in the case of Diptera, at the family level, the Malaise trap is also very similar to amber. Amber captured a higher diversity of arthropods than each of the artificial traps, based on our study of Mexican amber from the Middle Miocene, a time of climate optimum, where temperature and humidity were probably higher than in modern Central America. We conclude that the size bias is qualitatively independent of the kind of trap for non-extreme values. We suggest that frequent specimens in amber were not necessarily the most frequent arthropods in the former amber forest. Selected taxa with higher numbers of specimens appear in amber because of their ecology and behavior, usually closely related with a tree-inhabiting life. Finally, changes of diversity from the Middle Miocene to Recent time in Central and South America can be analyzed by comparing the rich amber faunas from Mexico and the Dominican Republic with the fauna trapped using sticky and Malaise traps in Central America.

  13. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants

    OpenAIRE

    Julieta Benítez-Malvido; Wesley Dáttilo; Ana Paola Martínez-Falcón; César Durán-Barrón; Jorge Valenzuela**; Sara López; Rafael Lombera

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological ...

  14. Surveillance of Mosquitoes and Selected Arthropod-Borne Viruses in the Context of Milan EXPO 2015.

    Science.gov (United States)

    Chiari, Mario; Calzolari, Mattia; Prosperi, Alice; Perulli, Simona; Faccin, Francesca; Avisani, Dominga; Cerioli, Monica; Zanoni, Mariagrazia; Tironi, Marco; Bertoletti, Marco; Defilippo, Francesco; Moreno, Ana; Farioli, Marco; Piatti, Alessandra; Dottori, Michele; Lelli, Davide; Lavazza, Antonio

    2016-01-01

    From 1 May 2015 to 31 October 2015 over 20 million visitors from all over the world visited the Universal Exhibition (EXPO) hosted by Milan (Lombardy region, Italy), raising concerns about the possible introduction of mosquito-borne diseases from endemic countries. The entomological surveillance protocol performed in Lombardy over the last three years was implemented in the EXPO area and in the two major regional airports using both Center for Disease Control CO₂ and Biogents Sentinel traps. This surveillance aimed to estimate the presence and densities of putative vectors, and also to support investigations, including the vector species involved and area of diffusion, on the local spread of Chikungunya, Dengue and West Nile viruses (WNV) by competent vectors. From 3544 mosquitoes belonging to five different species, 28 pools of Culex spp. and 45 pools of Aedes spp. were screened for the presence of WNV, and for both Chikungunya and flaviviruses, respectively. The entomological surveillance highlighted a low density of potential vectors in the surveyed areas and did not reveal the presence of Chikungunya or Dengue viruses in the local competent vectors inside the EXPO area or in the two airports. In addition, the surveillance reported a low density of Culex spp. mosquitoes, which all tested negative for WNV. PMID:27399756

  15. The seasonal variation of arthropods living on forest soil at different altitudes in fir (Abies nordmanniana subsp. bornmulleriana ecosystem in Bolu-Aladağ

    Directory of Open Access Journals (Sweden)

    Ahmet Duyar

    2016-07-01

    Full Text Available In the forest ecosystems, soil arthropods (Arthropoda, as primary and secondary consumers, have a significant role in litter decay and decomposition processes. The abundance, diversity and community structure of arthropods in soil ecosystem; give rapid response to change of site characteristics. The current study was aimed to determine of seasonal variation of soil arthropods on forest floor at different altitudes in Uludağ Fir (Abies nordmanniana subsp. bornmulleriana Mattf. ecosystem which is an important forest tree species in Turkey. The study was conducted in pure fir stands at 1200-1600 m altitudes (4 elevation gradients in Aladağ, Bolu. The sampling was carried out for each winter, spring, summer and autumn seasons. The samples were collected from forest floor by pitfall traps. Variations of abundance and diversity of arthropods were evaluated according to seasons and altitudes. The distributions in trophic levels and biological diversity of arthropods were also determined. During the study, the maximum abundance of arthropods was 7576 individuals/m² in summer among seasons, and was 7854 individuals/m² at 1200 m altitude. Shannon-Wiener Index (H′ and Species Richness (S′ values were detected in the pitfall traps (H′= 2.22; S′= 22.

  16. A rare lobopod with well-preserved eyes from Chengjiang Lagerst(a)tte and its implications for origin of arthropods

    Institute of Scientific and Technical Information of China (English)

    LIU Jianni; SHU Degan; HAN Jian; ZHANG Zhifei

    2004-01-01

    The origin of arthropods has long been one of the most hotly-debated subjects. Arthropods used to be thought closely related with annelids, but the two groups are now believed to be separated into two major realms within Protostomia on the basis of new molecular data. Although it is generally held by paleontologists that arthropods should be rooted in the early lobopods--a kind of worm-like creature with non-segmented legs, no intermediate forms have been found to bridge them. Here we report an organism with a mixture of characters, including features characteristic of arthropods (e.g., primary cephalization with paired eyes,paired antennae, and preliminary tagmosis) and of lobopods (e.g., worm-like body design, the dorsal spines, and non-segmented limbs or lobe-like legs). The discovery of the rare transitional form may throw new light on the origin of arthropods and suggests that the most primitive arthropods began with paired uniramous legs and the biramous ones evolved later.

  17. Uptake of Cadmium, Copper, Lead, and Zinc from Sediments by an Aquatic Macrophyte and by Terrestrial Arthropods in a Freshwater Wetland Ecosystem.

    Science.gov (United States)

    Kim, Heung-Tae; Kim, Jae Geun

    2016-08-01

    The objective of this study was to investigate trace-metal [cadmium (Cd), copper (Cu), lead (Pb), zinc (Zn)] biotransference and biomagnification in terrestrial biota at different trophic levels (primary producer-top predator) of a wetland ecosystem. We investigated whether metal concentrations in the sediment are reflected in terrestrial arthropods and aquatic plants. We sampled the floating-leaved plant Trapa japonica; its species-specific primary consumer, the leaf beetle Galerucella nipponensis; and two predatory arthropods (the water strider Gerris sp. and the wolf spider Arctosa sp.) from three wetlands with different sedimentary metal concentrations. The δ(13)C and δ(15)N signatures in the trophic link between the plants and the leaf beetles supported the specificity of their feeding relationship. The stable isotope signatures indicate that the leaf beetle could be an important link in the trophic transfer of the metals. Transference factors (TFs) were 1 for all biota, and the concentrations were positively correlated with the trophic levels. Thus, there may be Cu and Zn biomagnification in the arthropods. We noted TF 1 among the arthropods. Therefore, Cd is probably not biomagnified between T. japonica and G. nipponensis, but it might be biomagnified in the arthropods. The metal burden in terrestrial arthropods may also be influenced by uptake from the sediment by aquatic plants.

  18. Uptake of Cadmium, Copper, Lead, and Zinc from Sediments by an Aquatic Macrophyte and by Terrestrial Arthropods in a Freshwater Wetland Ecosystem.

    Science.gov (United States)

    Kim, Heung-Tae; Kim, Jae Geun

    2016-08-01

    The objective of this study was to investigate trace-metal [cadmium (Cd), copper (Cu), lead (Pb), zinc (Zn)] biotransference and biomagnification in terrestrial biota at different trophic levels (primary producer-top predator) of a wetland ecosystem. We investigated whether metal concentrations in the sediment are reflected in terrestrial arthropods and aquatic plants. We sampled the floating-leaved plant Trapa japonica; its species-specific primary consumer, the leaf beetle Galerucella nipponensis; and two predatory arthropods (the water strider Gerris sp. and the wolf spider Arctosa sp.) from three wetlands with different sedimentary metal concentrations. The δ(13)C and δ(15)N signatures in the trophic link between the plants and the leaf beetles supported the specificity of their feeding relationship. The stable isotope signatures indicate that the leaf beetle could be an important link in the trophic transfer of the metals. Transference factors (TFs) were 1 for all biota, and the concentrations were positively correlated with the trophic levels. Thus, there may be Cu and Zn biomagnification in the arthropods. We noted TF 1 among the arthropods. Therefore, Cd is probably not biomagnified between T. japonica and G. nipponensis, but it might be biomagnified in the arthropods. The metal burden in terrestrial arthropods may also be influenced by uptake from the sediment by aquatic plants. PMID:27306449

  19. Arthropods associated with pig carrion in two vegetation profiles of Cerrado in the State of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Thiago Augusto Rosa

    2011-09-01

    Full Text Available Forensic Entomology research has been concentrated in only a few localities of the "Cerrado" vegetation, the Brazilian Savannah. The present study had, as its objective, an examination of the diversity of arthropod fauna associated with the carcasses of Sus scrofa (Linnaeus in this biome. The study was conducted during the dry and humid periods in two Cerrado vegetation profiles of the State of Minas Gerais. The decaying process was slower and greater quantities of arthropods were collected during the dry period. Insects represented 99% of 161,116 arthropods collected. The majority of these were Diptera (80.2% and Coleoptera (8.8%. The entomofauna belong to 85 families and at least 212 species. Diptera were represented by 31 families and at least 132 species. Sarcophagidae (Diptera and Scarabaeidae (Coleoptera were the richest groups. Oxysarcodexia (Sarcophagidae presented the largest number of attracted species, however none of these species bred in the carcasses. The Coleoptera collected belong to at least 50 species of 21 families. Among these species, Dermestes maculatus and Necrobia rufipes were observed breeding in the carcasses. This study showed species with potential importance for estimating the postmortem interval (PMI, indicative of seasonal and environmental type located.

  20. Different acute toxicity of fipronil baits on invasive Linepithema humile supercolonies and some non-target ground arthropods.

    Science.gov (United States)

    Hayasaka, Daisuke; Kuwayama, Naoki; Takeo, Azuma; Ishida, Takanobu; Mano, Hiroyuki; Inoue, Maki N; Nagai, Takashi; Sánchez-Bayo, Francisco; Goka, Koichi; Sawahata, Takuo

    2015-08-01

    Fipronil is one of the most effective insecticides to control the invasive ant Linepithema humile, but its effectiveness has been assessed without considering the genetic differences among L. humile supercolonies. We hypothesized that the susceptibility of the ant to fipronil might differ among supercolonies. If so, dosage and concentration of fipronil may need to be adjusted for effective eradication of each supercolony. The relative sensitivities of four L. humile supercolonies established in Hyogo (Japan) to fipronil baits were examined based on their acute toxicity (48-h LC(50)). Toxicities of fipronil to seven ground arthropods, including four native ant species, one native isopoda, and two cockroaches were also determined and compared to that of L. humile supercolonies using species sensitivity distributions. Marked differences in susceptibility of fipronil were apparent among the supercolonies (P non-target species (330-2327 μg L(-1)) were in the same range as that of L. humile, and SSDs between the two species groups were not significantly different (t = -1.389, P = 0.180), suggesting that fipronil's insecticidal activity is practically the same for L. humile as for non-target arthropods. Therefore, if the invasive ant is to be controlled using fipronil, this would also affect the local arthropod biodiversity. Only the 'Japanese main supercolony' can be controlled with appropriate bait dosages of fipronil that would have little impact on the other species.