Are flying wildlife attracted to (or do they avoid) wind turbines?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Larkin, Ronald

A DOE-sponsored research project found strong evidence that flying wildlife avoid or are attracted to commercial-scale wind turbines from a distance. Some nocturnally migrating birds avoid flying near turbines and few or none change flight paths to approach them. High-flying bats less often avoid flying near turbines and some are attracted to them from a distance, although bats’ flight paths were often complex and convoluted. The findings are being prepared for submission to a peer-reviewed scientific journal (Larkin, in prep 2013).

The Enhancer of split complex arose prior to the diversification of schizophoran flies and is strongly conserved between Drosophila and stalk-eyed flies (Diopsidae)

PubMed Central

2011-01-01

Background In Drosophila, the Enhancer of split complex (E(spl)-C) comprises 11 bHLH and Bearded genes that function during Notch signaling to repress proneural identity in the developing peripheral nervous system. Comparison with other insects indicates that the basal state for Diptera is a single bHLH and Bearded homolog and that the expansion of the gene complex occurred in the lineage leading to Drosophila. However, comparative genomic data from other fly species that would elucidate the origin and sequence of gene duplication for the complex is lacking. Therefore, in order to examine the evolutionary history of the complex within Diptera, we reconstructed, using several fosmid clones, the entire E(spl)-complex in the stalk-eyed fly, Teleopsis dalmanni and collected additional homologs of E(spl)-C genes from searches of dipteran EST databases and the Glossina morsitans genome assembly. Results Comparison of the Teleopsis E(spl)-C gene organization with Drosophila indicates complete conservation in gene number and orientation between the species except that T. dalmanni contains a duplicated copy of E(spl)m5 that is not present in Drosophila. Phylogenetic analysis of E(spl)-complex bHLH and Bearded genes for several dipteran species clearly demonstrates that all members of the complex were present prior to the diversification of schizophoran flies. Comparison of upstream regulatory elements and 3' UTR domains between the species also reveals strong conservation for many of the genes and identifies several novel characteristics of E(spl)-C regulatory evolution including the discovery of a previously unidentified, highly conserved SPS+A domain between E(spl)mγ and E(spl)mβ. Conclusion Identifying the phylogenetic origin of E(spl)-C genes and their associated regulatory DNA is essential to understanding the functional significance of this well-studied gene complex. Results from this study provide numerous insights into the evolutionary history of the complex and will help refine the focus of studies examining the adaptive consequences of this gene expansion. PMID:22151427

Structural Basis of TLR5-Flagellin Recognition and Signaling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoon, Sung-il; Kurnasov, Oleg; Natarajan, Venkatesh

2012-03-01

Toll-like receptor 5 (TLR5) binding to bacterial flagellin activates signaling through the transcription factor NF-{kappa}B and triggers an innate immune response to the invading pathogen. To elucidate the structural basis and mechanistic implications of TLR5-flagellin recognition, we determined the crystal structure of zebrafish TLR5 (as a variable lymphocyte receptor hybrid protein) in complex with the D1/D2/D3 fragment of Salmonella flagellin, FliC, at 2.47 angstrom resolution. TLR5 interacts primarily with the three helices of the FliC D1 domain using its lateral side. Two TLR5-FliC 1:1 heterodimers assemble into a 2:2 tail-to-tail signaling complex that is stabilized by quaternary contacts of themore » FliC D1 domain with the convex surface of the opposing TLR5. The proposed signaling mechanism is supported by structure-guided mutagenesis and deletion analyses on CBLB502, a therapeutic protein derived from FliC.« less

Archive data base and handling system for the Orbiter flying qualities experiment program

NASA Technical Reports Server (NTRS)

Myers, T. T.; Dimarco, R.; Magdaleno, R. E.; Aponso, B. L.

1986-01-01

The OFQ archives data base and handling system assembled as part of the Orbiter Flying Qualities (OFQ) research of the Orbiter Experiments Program (EOX) are described. The purpose of the OFQ archives is to preserve and document shuttle flight data relevant to vehicle dynamics, flight control, and flying qualities in a form that permits maximum use for qualified users. In their complete form, the OFQ archives contain descriptive text (general information about the flight, signal descriptions and units) as well as numerical time history data. Since the shuttle program is so complex, the official data base contains thousands of signals and very complex entries are required to obtain data. The OFQ archives are intended to provide flight phase oriented data subsets with relevant signals which are easily identified for flying qualities research.

Two new species of sympatric Fergusonina flies (Diptera: Fergusoninidae) from bud galls on high elevation snow gums (Eucalyptus pauciflora Sieb. ex Spreng. complex) in the Australian Alps

USDA-ARS?s Scientific Manuscript database

Two species of Fergusonina Malloch fly, F. daviesae Nelson sp.n. and F. taylori Nelson sp.n. (Diptera: Fergusoninidae), are described from terminal leaf bud galls on high elevation snow gums (Eucalyptus pauciflora complex) in the Australian Alps. These species occur in sympatry at the six locations...

Existence of species complex largely reduced barcoding success for invasive species of Tephritidae: a case study in Bactrocera spp.

PubMed

Jiang, F; Jin, Q; Liang, L; Zhang, A B; Li, Z H

2014-11-01

Fruit flies in the family Tephritidae are the economically important pests that have many species complexes. DNA barcoding has gradually been verified as an effective tool for identifying species in a wide range of taxonomic groups, and there are several publications on rapid and accurate identification of fruit flies based on this technique; however, comprehensive analyses of large and new taxa for the effectiveness of DNA barcoding for fruit flies identification have been rare. In this study, we evaluated the COI barcode sequences for the diagnosis of fruit flies using 1426 sequences for 73 species of Bactrocera distributed worldwide. Tree-based [neighbour-joining (NJ)]; distance-based, such as Best Match (BM), Best Close Match (BCM) and Minimum Distance (MD); and character-based methods were used to evaluate the barcoding success rates obtained with maintaining the species complex in the data set, treating a species complex as a single taxon unit, and removing the species complex. Our results indicate that the average divergence between species was 14.04% (0.00-25.16%), whereas within a species this was 0.81% (0.00-9.71%); the existence of species complexes largely reduced the barcoding success for Tephritidae, for example relatively low success rates (74.4% based on BM and BCM and 84.8% based on MD) were obtained when the sequences from species complexes were included in the analysis, whereas significantly higher success rates were achieved if the species complexes were treated as a single taxon or removed from the data set - BM (98.9%), BCM (98.5%) and MD (97.5%), or BM (98.1%), BCM (97.4%) and MD (98.2%). © 2014 John Wiley & Sons Ltd.

Species diversity of Fergusonina Malloch gall flies (Diptera: Fergusoninidae) forming leaf bud galls on snow gum (Eucalyptus pauciflora Sieb. ex Spreng. complex), with a description of a new species from Tasmania

USDA-ARS?s Scientific Manuscript database

A new species of Fergusonina (Diptera: Fergusoninidae) fly is described from terminal leaf bud galls (TLBGs) from the Eucalyptus pauciflora Sieb. ex Spreng. (snow gum) species complex. Fergusonina tasmaniensis Nelson sp.n. is the first species from the genus Fergusonina to be described from Tasmania...

Bacterial Flagellin-Specific Chaperone FliS Interacts with Anti-Sigma Factor FlgM

PubMed Central

Galeva, Anna; Moroz, Natalia; Yoon, Young-Ho; Hughes, Kelly T.; Samatey, Fadel A.

2014-01-01

Flagella are extracellular organelles that propel bacteria. Each flagellum consists of a basal body, a hook, and a filament. The major protein of the filament is flagellin. Induction of flagellin gene expression coincides with secretion of FlgM. The role of FlgM is to inhibit FliA (σ28), a flagellum-specific RNA polymerase responsible for flagellin transcription. To prevent premature polymerization of newly synthesized flagellin molecules, FliS, the flagellin-specific chaperone, binds flagellin and facilitates its export. In this study, the interaction between FlgM and FliS from Salmonella enterica serovar Typhimurium was characterized using gel shift, intrinsic tryptophan fluorescence, circular dichroism, limited proteolysis, and cross-linking. We have demonstrated that (i) FliS and FlgM interact specifically, forming a 1:1 complex, (ii) the FliS binding site on FlgM is proximal to or even overlaps the binding site for FliA, and (iii) FliA competes with FliS for FlgM binding. PMID:24415724

Bot fly parasitism of the red-backed vole: host survival, infection risk, and population growth.

PubMed

Lemaître, Jérôme; Fortin, Daniel; Montiglio, Pierre-Olivier; Darveau, Marcel

2009-03-01

Parasites can play an important role in the dynamics of host populations, but empirical evidence remains sparse. We investigated the role of bot fly (Cuterebra spp.) parasitism in red-backed voles (Myodes gapperi) by first assessing the impacts of the parasite on the probability of vole survival under stressful conditions as well as on the reproductive activity of females. We then identified the main factors driving both the individual risk of infection and the abundance of bot flies inside red-backed voles. Finally, we evaluated the impacts of bot fly prevalence on the growth rate of vole populations between mid-July and mid-August. Thirty-six populations of red-backed voles were sampled in the boreal forest of Québec, Canada. The presence and the abundance of parasites in voles, two host life history traits (sex and body condition), three indices of habitat complexity (tree basal area, sapling basal area, coarse woody debris volume), and vole abundance were considered in models evaluating the effects of bot flies on host populations. We found that the probability of survival of red-backed voles in live traps decreased with bot fly infection. Both the individual risk of infection and the abundance of bot flies in red-backed voles were driven mainly by vole abundance rather than by the two host life history traits or the three variables of habitat complexity. Parasitism had population consequences: bot fly prevalence was linked to a decrease in short-term growth rate of vole populations over the summer. We found that bot flies have the potential to reduce survival of red-backed voles, an effect that may apply to large portions of populations.

Three new species of Fergusonina Malloch fly (Diptera: Fergusoninidae) from bud galls on Eucalyptus L'Her. (E. baxteri (Benth.) Maiden & Blakely complex, E. dalrympleana Maiden and E. pauciflora Sieb. ex Spreng.)

USDA-ARS?s Scientific Manuscript database

Three Fergusonina (Diptera: Fergusoninidae) flies are described from terminal leaf bud galls on Eucalyptus L'Hér. from south eastern Australia. Fergusonina omlandi Nelson and Yeates sp. nov. is the third fly from the genus Fergusonina to be described from the Eucalyptus pauciflora Sieb. ex Spreng. (...

Complexity of acetylcholinesterases in biting flies and ticks

USDA-ARS?s Scientific Manuscript database

Acetylcholinesterase (AChE) inhibitors function as pesticides for invertebrates, vertebrate nerve agents, and medicine to reduce cognitive effects of Alzheimer’s disease. Organophosphate (OP) pesticides have been widely used to control biting flies and ticks, however, OP-resistance has compromised c...

Molecular characterization and immunolocalization of the olfactory co-recepter Orco from two blood-feeding muscid flies, the stable fly (Stomoxys calcitrans, L.) and the horn fly (Haematobia irritans irritans, L.)

PubMed Central

Olafson, Pia Untalan

2012-01-01

Biting flies are economically important, blood-feeding pests of medical and veterinary significance. Chemosensory-based biting fly behaviors, such as host/nutrient source localization and ovipositional site selection, are intriguing targets for the development of supplemental control strategies. In an effort to expand our understanding of biting fly chemosensory pathways, transcripts encoding the highly conserved insect odorant co-receptor (Orco) were isolated from two representative biting fly species, the stable fly (Scal\\Orco) and the horn fly (Hirr\\Orco). Orco forms a complex with an odor-specific odorant receptor to form an odor-gated ion channel. The biting fly transcripts were predicted to encode proteins with 87% – 94% amino acid similarity to published insect Orco sequences and were detected in various immature stages as well as in adult structures associated with olfaction, i.e. antennae and maxillary palps, and gustation, i.e. proboscis. Further, the relevant proteins were immunolocalized to specific antennal sensilla using anti-serum raised against a peptide sequence conserved between the two fly species. Results from this study provide a basis for functional evaluation of repellent/attractant effects on as yet uncharacterized stable fly and horn fly conventional odorant receptors. PMID:23278866

Complex roles of myoglianin in regulating adult performance and lifespan

PubMed Central

2017-01-01

ABSTRACT Myoglianin, the Drosophila homolog of the secreted vertebrate proteins Myostatin and GDF-11, is an important regulator of neuronal modeling, and synapse function and morphology. While Myoglianin suppression during development elicits positive effects on the neuromuscular system, genetic manipulations of myoglianin expression levels have a varied effect on the outcome of performance tests in aging flies. Specifically, Myoglianin preserves jumping ability, has no effect on negative geotaxis, and negatively regulates flight performance in aging flies. In addition, Myoglianin exhibits a tissue-specific effect on longevity, with myoglianin upregulation in glial cells increasing the median lifespan. These findings indicate complex role for this TGF-β-like protein in governing neuromuscular signaling and consequent behavioral outputs and lifespan in adult flies. PMID:28837401

Intracellular regulation of the insect chemoreceptor complex impacts odour localization in flying insects.

PubMed

Getahun, Merid N; Thoma, Michael; Lavista-Llanos, Sofia; Keesey, Ian; Fandino, Richard A; Knaden, Markus; Wicher, Dieter; Olsson, Shannon B; Hansson, Bill S

2016-11-01

Flying insects are well known for airborne odour tracking and have evolved diverse chemoreceptors. While ionotropic receptors (IRs) are found across protostomes, insect odorant receptors (ORs) have only been identified in winged insects. We therefore hypothesized that the unique signal transduction of ORs offers an advantage for odour localization in flight. Using Drosophila, we found expression and increased activity of the intracellular signalling protein PKC in antennal sensilla following odour stimulation. Odour stimulation also enhanced phosphorylation of the OR co-receptor Orco in vitro, while site-directed mutation of Orco or mutations in PKC subtypes reduced the sensitivity and dynamic range of OR-expressing neurons in vivo, but not IR-expressing neurons. We ultimately show that these mutations reduce competence for odour localization of flies in flight. We conclude that intracellular regulation of OR sensitivity is necessary for efficient odour localization, which suggests a mechanistic advantage for the evolution of the OR complex in flying insects. © 2016. Published by The Company of Biologists Ltd.

Rb-Sr, K-Ar, and stable isotope evidence for the ages and sources of fluid components of gold-bearing quartz veins in the northern Sierra Nevada foothills metamorphic belt, California

USGS Publications Warehouse

Böhlke, John Karl; Kistler, R. W.

1986-01-01

Gold-bearing quartz veins occur in and near major fault zones in deformed oceanic and island-arc rocks west of the main outcrop of the Sierra Nevada composite batholith. Veins typically occupy minor reverse faults that crosscut blueschist to amphibolite-grade metamorphic rocks whose metamorphic ages range from early Paleozoic to Jurassic. Vein micas and carbonate-quartz-mica assemblages that formed by hydrothermal metasomatism of ultramafic wall rocks in the Alleghany, Grass Valley, Washington, and Mother Lode districts yield concordant K-Ar and Rb-Sr ages. The dated veins are significantly younger than prograde metamorphism, penetrative deformation, and accretion of their host rocks to the continental margin. New and previously published mineralization ages from 13 localities in the Sierra foothills range from about 140 to 110 m.y. ago, with mean and median between 120 and 115 m.y. The age relations suggest that mineralizing fluids were set in motion by deep magmatic activity related to the resumption of east-dipping subduction along the western margin of North America following the Late Jurassic Nevadan collision event.CO 2 -bearing fluids responsible for metasomatism and much of the vein mica, carbonate, albite, and quartz deposition in several northern mines were isotopically heavy (delta 18 O [asymp] 8-14ppm; delta D between about -10 and -50ppm) and do not resemble seawater, magmatic, or meteoric waters. Metasomatic and vein-filling mica, dolomite, magnesite, and quartz in altered ultramafic rocks generally formed from fluids with similar Sr and O isotope ratios at a given locality. Consistent quartz-mica delta 18 O fractionations (delta 18 O (sub Q-M) = 4.5-4.9ppm) from various localities imply uniform equilibration temperatures, probably between 300 degrees and 350 degrees C. On a local (mine) scale, fluids responsible for both carbonate alteration of mafic and ultramafic wall rocks and albitic alteration of felsic and pelitic rocks had similar Sr isotope ratios.Samples from three veins in the central Alleghany district fit a 115.7 + or - 3-m.y. Rb-Sr isochron with a ( 87 Sr/ 86 Sr) i value of approximately 0.7119. Inferred 87 Sr/ 86 Sr ratios of metasomatic fluids from mines in different parts of the foothills region vary considerably (0.704-0.718), suggesting that Sr was derived from sources ranging from "western assemblage" Mesozoic ophiolitic or arc volcanic rocks to early Paleozoic continent-derived clastic rocks of the Shoo Fly Complex. Systematic geographic variations in both Sr and O isotopes can be rationalized by assuming extensive fluid interaction with rocks similar to the ones that are exposed within a few kilometers of the veins, but the ultimate sources of the fluids, and of Au and other constituents, may be independent of these. Isotopically lighter (meteoric?) fluids deposited some late quartz overgrowths and occupied secondary fluid inclusions in earlier vein quartz.

CD4+ T cell epitopes of FliC conserved between strains of Burkholderia: implications for vaccines against melioidosis and cepacia complex in cystic fibrosis.

PubMed

Musson, Julie A; Reynolds, Catherine J; Rinchai, Darawan; Nithichanon, Arnone; Khaenam, Prasong; Favry, Emmanuel; Spink, Natasha; Chu, Karen K Y; De Soyza, Anthony; Bancroft, Gregory J; Lertmemongkolchai, Ganjana; Maillere, Bernard; Boyton, Rosemary J; Altmann, Daniel M; Robinson, John H

2014-12-15

Burkholderia pseudomallei is the causative agent of melioidosis characterized by pneumonia and fatal septicemia and prevalent in Southeast Asia. Related Burkholderia species are strong risk factors of mortality in cystic fibrosis (CF). The B. pseudomallei flagellar protein FliC is strongly seroreactive and vaccination protects challenged mice. We assessed B. pseudomallei FliC peptide binding affinity to multiple HLA class II alleles and then assessed CD4 T cell immunity in HLA class II transgenic mice and in seropositive individuals in Thailand. T cell hybridomas were generated to investigate cross-reactivity between B. pseudomallei and the related Burkholderia species associated with Cepacia Complex CF. B. pseudomallei FliC contained several peptide sequences with ability to bind multiple HLA class II alleles. Several peptides were shown to encompass strong CD4 T cell epitopes in B. pseudomallei-exposed individuals and in HLA transgenic mice. In particular, the p38 epitope is robustly recognized by CD4 T cells of seropositive donors across diverse HLA haplotypes. T cell hybridomas against an immunogenic B. pseudomallei FliC epitope also cross-reacted with orthologous FliC sequences from Burkholderia multivorans and Burkholderia cenocepacia, important pathogens in CF. Epitopes within FliC were accessible for processing and presentation from live or heat-killed bacteria, demonstrating that flagellin enters the HLA class II Ag presentation pathway during infection of macrophages with B. cenocepacia. Collectively, the data support the possibility of incorporating FliC T cell epitopes into vaccination programs targeting both at-risk individuals in B. pseudomallei endemic regions as well as CF patients. Copyright © 2014 by The American Association of Immunologists, Inc.

Neural veils and the will to historical critique: why historians of science need to take the neuro-turn seriously.

PubMed

Cooter, Roger

2014-03-01

Taking the neuro-turn is like becoming the victim of mind parasites. It's unwilled (although there are those who will it at a superficial level for various strategic reasons). You can't see mind parasites; they make you think things without allowing you to know why you think them. Indeed, they generate the cognitive inability to be other than delighted with the circumstances of your affected cognition. It's not as if you can take off your thinking cap and shoo the pests away. You can't see them--or even know that you could want to. You can't stand on the outside looking in at your cognitive processes. But historically speaking, you are also inside a (broadly postmodern) culture and (broadly neoliberal) socioeconomic order that places the legitimacy of the neuro beyond critique. And the neuro-turn does more: it delegitimizes critique itself, at least as we have known it since Marx. This essay briefly explores how we got here, what the "here" is, and what its implications are for historical critique.

Drosophila as an In Vivo Model for Human Neurodegenerative Disease

PubMed Central

McGurk, Leeanne; Berson, Amit; Bonini, Nancy M.

2015-01-01

With the increase in the ageing population, neurodegenerative disease is devastating to families and poses a huge burden on society. The brain and spinal cord are extraordinarily complex: they consist of a highly organized network of neuronal and support cells that communicate in a highly specialized manner. One approach to tackling problems of such complexity is to address the scientific questions in simpler, yet analogous, systems. The fruit fly, Drosophila melanogaster, has been proven tremendously valuable as a model organism, enabling many major discoveries in neuroscientific disease research. The plethora of genetic tools available in Drosophila allows for exquisite targeted manipulation of the genome. Due to its relatively short lifespan, complex questions of brain function can be addressed more rapidly than in other model organisms, such as the mouse. Here we discuss features of the fly as a model for human neurodegenerative disease. There are many distinct fly models for a range of neurodegenerative diseases; we focus on select studies from models of polyglutamine disease and amyotrophic lateral sclerosis that illustrate the type and range of insights that can be gleaned. In discussion of these models, we underscore strengths of the fly in providing understanding into mechanisms and pathways, as a foundation for translational and therapeutic research. PMID:26447127

Drosophila as an In Vivo Model for Human Neurodegenerative Disease.

PubMed

McGurk, Leeanne; Berson, Amit; Bonini, Nancy M

2015-10-01

With the increase in the ageing population, neurodegenerative disease is devastating to families and poses a huge burden on society. The brain and spinal cord are extraordinarily complex: they consist of a highly organized network of neuronal and support cells that communicate in a highly specialized manner. One approach to tackling problems of such complexity is to address the scientific questions in simpler, yet analogous, systems. The fruit fly, Drosophila melanogaster, has been proven tremendously valuable as a model organism, enabling many major discoveries in neuroscientific disease research. The plethora of genetic tools available in Drosophila allows for exquisite targeted manipulation of the genome. Due to its relatively short lifespan, complex questions of brain function can be addressed more rapidly than in other model organisms, such as the mouse. Here we discuss features of the fly as a model for human neurodegenerative disease. There are many distinct fly models for a range of neurodegenerative diseases; we focus on select studies from models of polyglutamine disease and amyotrophic lateral sclerosis that illustrate the type and range of insights that can be gleaned. In discussion of these models, we underscore strengths of the fly in providing understanding into mechanisms and pathways, as a foundation for translational and therapeutic research. Copyright © 2015 by the Genetics Society of America.

DNA barcodes affirm that 16 species of apparently generalist tropical parasitoid flies (Diptera, Tachinidae) are not all generalists

PubMed Central

Smith, M. Alex; Wood, D. Monty; Janzen, Daniel H.; Hallwachs, Winnie; Hebert, Paul D. N.

2007-01-01

Many species of tachinid flies are viewed as generalist parasitoids because what is apparently a single species of fly has been reared from many species of caterpillars. However, an ongoing inventory of the tachinid flies parasitizing thousands of species of caterpillars in Area de Conservación Guanacaste, northwestern Costa Rica, has encountered >400 species of specialist tachinids with only a few generalists. We DNA-barcoded 2,134 flies belonging to what appeared to be the 16 most generalist of the reared tachinid morphospecies and encountered 73 mitochondrial lineages separated by an average of 4% sequence divergence. These lineages are supported by collateral ecological information and, where tested, by independent nuclear markers (28S and ITS1), and we therefore view these lineages as provisional species. Each of the 16 apparently generalist species dissolved into one of four patterns: (i) a single generalist species, (ii) a pair of morphologically cryptic generalist species, (iii) a complex of specialist species plus a generalist, or (iv) a complex of specialists with no remaining generalist. In sum, there remained 9 generalist species among the 73 mitochondrial lineages we analyzed, demonstrating that a generalist lifestyle is possible for a tropical caterpillar parasitoid fly. These results reinforce the emerging suspicion that estimates of global species richness are likely underestimates for parasitoids (which may constitute as much as 20% of all animal life) and that the strategy of being a tropical generalist parasitic fly may be yet more unusual than has been envisioned for tachinids. PMID:17360352

Canadian Snowbirds fly over KSC

NASA Image and Video Library

2018-05-09

The Canadian Forces Snowbirds fly in Concorde formation over the Kennedy Space Center Visitor Complex. The Snowbirds, Canada’s air demonstration team, carried out a practice flight over NASA’s Kennedy Space Center and Cape Canaveral Air Force Station in Florida on Wednesday, May 9, 2018, between their scheduled U.S. air shows.

Schlieren photography on freely flying hawkmoth.

PubMed

Liu, Yun; Roll, Jesse; Van Kooten, Stephen; Deng, Xinyan

2018-05-01

The aerodynamic force on flying insects results from the vortical flow structures that vary both spatially and temporally throughout flight. Due to these complexities and the inherent difficulties in studying flying insects in a natural setting, a complete picture of the vortical flow has been difficult to obtain experimentally. In this paper, Schlieren , a widely used technique for highspeed flow visualization, was adapted to capture the vortex structures around freely flying hawkmoth ( Manduca ). Flow features such as leading-edge vortex, trailing-edge vortex, as well as the full vortex system in the wake were visualized directly. Quantification of the flow from the Schlieren images was then obtained by applying a physics-based optical flow method, extending the potential applications of the method to further studies of flying insects. © 2018 The Author(s).

Origin, acquisition and diversification of heritable bacterial endosymbionts in louse flies and bat flies.

PubMed

Duron, Olivier; Schneppat, Ulrich E; Berthomieu, Arnaud; Goodman, Steven M; Droz, Boris; Paupy, Christophe; Nkoghe, Judicaël Obame; Rahola, Nil; Tortosa, Pablo

2014-04-01

The γ-proteobacterium Arsenophonus and its close relatives (Arsenophonus and like organisms, ALOs) are emerging as a novel clade of endosymbionts, which are exceptionally widespread in insects. The biology of ALOs is, however, in most cases entirely unknown, and it is unclear how these endosymbionts spread across insect populations. Here, we investigate this aspect through the examination of the presence, the diversity and the evolutionary history of ALOs in 25 related species of blood-feeding flies: tsetse flies (Glossinidae), louse flies (Hippoboscidae) and bat flies (Nycteribiidae and Streblidae). While these endosymbionts were not found in tsetse flies, we identify louse flies and bat flies as harbouring the highest diversity of ALO strains reported to date, including a novel ALO clade, as well as Arsenophonus and the recently described Candidatus Aschnera chinzeii. We further show that the origin of ALO endosymbioses extends deep into the evolutionary past of louse flies and bat flies, and that it probably played a major role in the ecological specialization of their hosts. The evolutionary history of ALOs is notably complex and was shaped by both vertical transmission and horizontal transfers with frequent host turnover and apparent symbiont replacement in host lineages. In particular, ALOs have evolved repeatedly and independently close relationships with diverse groups of louse flies and bat flies, as well as phylogenetically more distant insect families, suggesting that ALO endosymbioses are exceptionally dynamic systems. © 2014 John Wiley & Sons Ltd.

DNA barcode variability and host plant usage of fruit flies (Diptera: Tephritidae) in Thailand.

PubMed

Kunprom, Chonticha; Pramual, Pairot

2016-10-01

The objectives of this study were to examine the genetic variation in fruit flies (Diptera: Tephritidae) in Thailand and to test the efficiency of the mitochondrial cytochrome c oxidase subunit I (COI) barcoding region for species-level identification. Twelve fruit fly species were collected from 24 host plant species of 13 families. The number of host plant species for each fruit fly species ranged between 1 and 11, with Bactrocera correcta found in the most diverse host plants. A total of 123 COI sequences were obtained from these fruit fly species. Sequences from the NCBI database were also included, for a total of 17 species analyzed. DNA barcoding identification analysis based on the best close match method revealed a good performance, with 94.4% of specimens correctly identified. However, many specimens (3.6%) had ambiguous identification, mostly due to intra- and interspecific overlap between members of the B. dorsalis complex. A phylogenetic tree based on the mitochondrial barcode sequences indicated that all species, except for the members of the B. dorsalis complex, were monophyletic with strong support. Our work supports recent calls for synonymization of these species. Divergent lineages were observed within B. correcta and B. tuberculata, and this suggested that these species need further taxonomic reexamination.

Predictability and hierarchy in Drosophila behavior.

PubMed

Berman, Gordon J; Bialek, William; Shaevitz, Joshua W

2016-10-18

Even the simplest of animals exhibit behavioral sequences with complex temporal dynamics. Prominent among the proposed organizing principles for these dynamics has been the idea of a hierarchy, wherein the movements an animal makes can be understood as a set of nested subclusters. Although this type of organization holds potential advantages in terms of motion control and neural circuitry, measurements demonstrating this for an animal's entire behavioral repertoire have been limited in scope and temporal complexity. Here, we use a recently developed unsupervised technique to discover and track the occurrence of all stereotyped behaviors performed by fruit flies moving in a shallow arena. Calculating the optimally predictive representation of the fly's future behaviors, we show that fly behavior exhibits multiple time scales and is organized into a hierarchical structure that is indicative of its underlying behavioral programs and its changing internal states.

Resolving cryptic species complexes of major tephritid pests

PubMed Central

Hendrichs, Jorge; Vera, M. Teresa; De Meyer, Marc; Clarke, Anthony R.

2015-01-01

Abstract An FAO/IAEA Co-ordinated Research Project (CRP) on “Resolution of Cryptic Species Complexes of Tephritid Pests to Overcome Constraints to SIT Application and International Trade” was conducted from 2010 to 2015. As captured in the CRP title, the objective was to undertake targeted research into the systematics and diagnostics of taxonomically challenging fruit fly groups of economic importance. The scientific output was the accurate alignment of biological species with taxonomic names; which led to the applied outcome of assisting FAO and IAEA Member States in overcoming technical constraints to the application of the Sterile Insect Technique (SIT) against pest fruit flies and the facilitation of international agricultural trade. Close to 50 researchers from over 20 countries participated in the CRP, using coordinated, multidisciplinary research to address, within an integrative taxonomic framework, cryptic species complexes of major tephritid pests. The following progress was made for the four complexes selected and studied: Anastrepha fraterculus complex – Eight morphotypes and their geographic and ecological distributions in Latin America were defined. The morphotypes can be considered as distinct biological species on the basis of differences in karyotype, sexual incompatibility, post-mating isolation, cuticular hydrocarbon, pheromone, and molecular analyses. Discriminative taxonomic tools using linear and geometric morphometrics of both adult and larval morphology were developed for this complex. Bactrocera dorsalis complex – Based on genetic, cytogenetic, pheromonal, morphometric, and behavioural data, which showed no or only minor variation between the Asian/African pest fruit flies Bactrocera dorsalis, Bactrocera papayae, Bactrocera philippinensis and Bactrocera invadens, the latter three species were synonymized with Bactrocera dorsalis. Of the five target pest taxa studied, only Bactrocera dorsalis and Bactrocera carambolae remain as scientifically valid names. Molecular and pheromone markers are now available to distinguish Bactrocera dorsalis from Bactrocera carambolae. Ceratitis FAR Complex (Ceratitis fasciventris, Ceratitis anonae, Ceratitis rosa) – Morphology, morphometry, genetic, genomic, pheromone, cuticular hydrocarbon, ecology, behaviour, and developmental physiology data provide evidence for the existence of five different entities within this fruit fly complex from the African region. These are currently recognised as Ceratitis anonae, Ceratitis fasciventris (F1 and F2), Ceratitis rosa and a new species related to Ceratitis rosa (R2). The biological limits within Ceratitis fasciventris (i.e. F1 and F2) are not fully resolved. Microsatellites markers and morphological identification tools for the adult males of the five different FAR entities were developed based on male leg structures. Zeugodacus cucurbitae (formerly Bactrocera (Zeugodacus) cucurbitae) – Genetic variability was studied among melon fly populations throughout its geographic range in Africa and the Asia/Pacific region and found to be limited. Cross-mating studies indicated no incompatibility or sexual isolation. Host preference and genetic studies showed no evidence for the existence of host races. It was concluded that the melon fly does not represent a cryptic species complex, neither with regard to geographic distribution nor to host range. Nevertheless, the higher taxonomic classification under which this species had been placed, by the time the CRP was started, was found to be paraphyletic; as a result the subgenus Zeugodacus was elevated to genus level. PMID:26798252

Association of Lutzomyia columbiana (Diptera: Psychodidae) with a leishmaniasis focus in Colombia due to species of the Leishmania mexicana complex.

PubMed

Montoya-Lerma, J; Cadena, H; Segura, I; Travi, B L

1999-01-01

In Colombia, Leishmania mexicana has a scattered geographical distribution and no sand fly vectors have been associated with its transmission. During the present study, the anthropophilic sand fly Lutzomyia columbiana was found to be the only species collected using diverse methods, in a small focus of Le. mexicana in the municipality of Samaniego, SW Colombia. Ecological data indicate that this sand fly species is present in both peri and intradomestic habitats, where it readily bites man. Further evidence comes from experimental infections of wild-caught Lu. columbiana with Le. mexicana after feeding on infected hamsters. Based on these results, it is suggested that this sand fly is the most likely vector in the study area, suggesting the existence of a previously unknown sand fly-parasite association.

Destruction of inorganic municipal solid waste incinerator fly ash in a DC arc plasma furnace.

PubMed

Zhao, Peng; Ni, Guohua; Jiang, Yiman; Chen, Longwei; Chen, Mingzhou; Meng, Yuedong

2010-09-15

Due to the toxicity of dioxins, furans and heavy metals, there is a growing environmental concern on municipal solid waste incinerator (MSWI) fly ash in China. The purpose of this study is directed towards the volume-reduction of fly ash without any additive by thermal plasma and recycling of vitrified slag. This process uses extremely high-temperature in an oxygen-starved environment to completely decompose complex waste into very simple molecules. For developing the proper plasma processes to treat MSWI fly ash, a new crucible-type plasma furnace was built. The melting process metamorphosed fly ash to granulated slag that was less than 1/3 of the volume of the fly ash, and about 64% of the weight of the fly ash. The safety of the vitrified slag was tested. The properties of the slag were affected by the differences in the cooling methods. Water-cooled and composite-cooled slag showed more excellent resistance against the leaching of heavy metals and can be utilized as building material without toxicity problems. Copyright 2010 Elsevier B.V. All rights reserved.

Predicting fruit fly's sensing rate with insect flight simulations.

PubMed

Chang, Song; Wang, Z Jane

2014-08-05

Without sensory feedback, flies cannot fly. Exactly how various feedback controls work in insects is a complex puzzle to solve. What do insects measure to stabilize their flight? How often and how fast must insects adjust their wings to remain stable? To gain insights into algorithms used by insects to control their dynamic instability, we develop a simulation tool to study free flight. To stabilize flight, we construct a control algorithm that modulates wing motion based on discrete measurements of the body-pitch orientation. Our simulations give theoretical bounds on both the sensing rate and the delay time between sensing and actuation. Interpreting our findings together with experimental results on fruit flies' reaction time and sensory motor reflexes, we conjecture that fruit flies sense their kinematic states every wing beat to stabilize their flight. We further propose a candidate for such a control involving the fly's haltere and first basalar motor neuron. Although we focus on fruit flies as a case study, the framework for our simulation and discrete control algorithms is applicable to studies of both natural and man-made fliers.

High-resolution remotely sensed small target detection by imitating fly visual perception mechanism.

PubMed

Huang, Fengchen; Xu, Lizhong; Li, Min; Tang, Min

2012-01-01

The difficulty and limitation of small target detection methods for high-resolution remote sensing data have been a recent research hot spot. Inspired by the information capture and processing theory of fly visual system, this paper endeavors to construct a characterized model of information perception and make use of the advantages of fast and accurate small target detection under complex varied nature environment. The proposed model forms a theoretical basis of small target detection for high-resolution remote sensing data. After the comparison of prevailing simulation mechanism behind fly visual systems, we propose a fly-imitated visual system method of information processing for high-resolution remote sensing data. A small target detector and corresponding detection algorithm are designed by simulating the mechanism of information acquisition, compression, and fusion of fly visual system and the function of pool cell and the character of nonlinear self-adaption. Experiments verify the feasibility and rationality of the proposed small target detection model and fly-imitated visual perception method.

Canadian Snowbirds fly over KSC

NASA Image and Video Library

2018-05-09

The Canadian Forces Snowbirds fly in Concorde formation over Launch Complex 39B and the Space Coast shoreline at NASA’s Kennedy Space Center in Florida. The Snowbirds, Canada’s air demonstration team, carried out a practice flight over Kennedy and nearby Cape Canaveral Air Force Station in Florida on Wednesday, May 9, 2018, between their scheduled U.S. air shows.

Leucine-Rich Repeat Kinase 2 interacts with Parkin, DJ-1 and PINK-1 in a Drosophila melanogaster model of Parkinson's disease.

PubMed

Venderova, Katerina; Kabbach, Ghassan; Abdel-Messih, Elizabeth; Zhang, Yi; Parks, Robin J; Imai, Yuzuru; Gehrke, Stephan; Ngsee, Johnny; Lavoie, Matthew J; Slack, Ruth S; Rao, Yong; Zhang, Zhuohua; Lu, Bingwei; Haque, M Emdadul; Park, David S

2009-11-15

Mutations in the LRRK2 gene are the most common genetic cause of familial Parkinson's disease (PD). However, its physiological and pathological functions are unknown. Therefore, we generated several independent Drosophila lines carrying WT or mutant human LRRK2 (mutations in kinase, COR or LRR domains, resp.). Ectopic expression of WT or mutant LRRK2 in dopaminergic neurons caused their significant loss accompanied by complex age-dependent changes in locomotor activity. Overall, the ubiquitous expression of LRRK2 increased lifespan and fertility of the flies. However, these flies were more sensitive to rotenone. LRRK2 expression in the eye exacerbated retinal degeneration. Importantly, in double transgenic flies, various indices of the eye and dopaminergic survival were modified in a complex fashion by a concomitant expression of PINK1, DJ-1 or Parkin. This evidence suggests a genetic interaction between these PD-relevant genes.

Description of evandromyia spelunca, a new phlebotomine species of the cortelezzii complex, from a cave in Minas Gerais State, Brazil (Diptera: Psychodidae: Phlebotominae).

PubMed

Carvalho, Gustavo M L; Brazil, Reginaldo P; Sanguinette, Cristiani C; Filho, José D Andrade

2011-08-09

The cave fauna of the Brazil is poorly documented, and among the insects those live or frequent caves and their adjacent environments phlebotomine sand flies call for special attention because several species are vectors of pathogens among vertebrates hosts. A new species of sand fly from Minas Gerais is described based in females and males collected in a cave of the municipality of Lassance. The morphological characters of the new species permit to include in the Evandromyia genus, cortelezzii complex. This complex consists of three species: Evandromyia corumbaensis (Galati, Nunes, Oshiro & Rego, 1989), Evandromyia cortelezzii (Brethes, 1923) and Evandromyia sallesi (Galvao & Coutinho, 1940). The new species can be separate from the others of the cortelezzii complex through morphological characters of the male terminalia and female spermathecae.

Biomedically relevant chemical and physical properties of coal combustion products.

PubMed Central

Fisher, G L

1983-01-01

The evaluation of the potential public and occupational health hazards of developing and existing combustion processes requires a detailed understanding of the physical and chemical properties of effluents available for human and environmental exposures. These processes produce complex mixtures of gases and aerosols which may interact synergistically or antagonistically with biological systems. Because of the physicochemical complexity of the effluents, the biomedically relevant properties of these materials must be carefully assessed. Subsequent to release from combustion sources, environmental interactions further complicate assessment of the toxicity of combustion products. This report provides an overview of the biomedically relevant physical and chemical properties of coal fly ash. Coal fly ash is presented as a model complex mixture for health and safety evaluation of combustion processes. PMID:6337824

Brazilian Pampa Biome Honey Protects Against Mortality, Locomotor Deficits and Oxidative Stress Induced by Hypoxia/Reperfusion in Adult Drosophila melanogaster.

PubMed

Cruz, L C; Ecker, A; Dias, R S; Seeger, R L; Braga, M M; Boligon, A A; Martins, I K; Costa-Silva, D G; Barbosa, N V; Cañedo, A D; Posser, T; Franco, J L

2016-02-01

We aimed to investigate the potential beneficial effects of the Brazilian Pampa biome honey in a Drosophila-based hypoxia model. Adult flies were reared in standard medium in the presence or absence of honey (at a final concentration of 10 % in medium). Then, control flies (4 % sucrose in medium) and honey-treated flies were submitted to hypoxia. Subsequently, flies were analyzed for mortality, neurolocomotor behavior (negative geotaxis), mitochondrial/oxidative stress parameters and expression of hypoxia/stress related genes by RT-qPCR. The HPLC analysis revealed the presence of phenolics and flavonoids in the studied honey. Caffeic acid was the major compound followed by p-coumaric acid and kaempferol. The presence of such compounds was correlated with a substantial antioxidant activity in vitro. Flies subjected to hypoxia presented marked mortality, locomotor deficits and changes in oxidative stress and mitochondrial activity parameters. Honey treatment was able to completely block mortality and locomotor phenotypes. In addition, honey was able to reverse ROS production and hypoxia-induced changes in mitochondrial complex I and II activity. Hypoxia also induced an up-regulation in mRNA expression of Sima (HIF-1), NFκβ, NRF2, HOX, AKT-1, InR, dILP2, dILP5 and HSP27. Honey treatment was not able to modulate changes in the tested genes, indicating that its protective effects involve additional mechanisms other than transcriptional activity of hypoxia-driven adaptive responses in flies. Our results demonstrated, for the first time, the beneficial effects of honey against the deleterious effects of hypoxia/reperfusion processes in a complex organism.

Leishmania sand fly interaction: progress and challenges.

PubMed

Bates, Paul A

2008-08-01

Complex interactions occurs between Leishmania parasites and their sand fly vectors. Promastigotes of Leishmania live exclusively within the gut, possess flagella and are motile, and kinesins, kinases and G proteins have been described that play a role in regulating flagellar assembly. Movement within the gut is not random: promastigotes can detect gradients of solutes via chemotaxis and osmotaxis. Further they use their flagella to attach to the fly midgut using surface glyconconjugates, a key step in establishment of the infection. Differentiation of mammal-infective stages is characterised by significant biochemical and cellular remodelling. Further, the parasites can manipulate the behaviour of the vector to maximise their transmission, and flies may even deliver altruistic apoptotic forms to aid transmission of infective stages.

Sorption of cadmium and lead by clays from municipal incinerator ash- water suspensions

USGS Publications Warehouse

Roy, W.R.; Krapac, I.G.; Steele, J.D.

1993-01-01

The effect of Cl complexation in extracts of a flue gas-scrubber incinerator fly ash sample on the sorption of Cd and Pb by kaolinite and illite was investigated using batch-sorption methods. In the pH range of 5 to 9, Cl complexation may reduce sorption and thus increase the mobility of these metals. When an ash-water suspension was acidified to pH 6.85, the dissolution of Cl and Ca essentially eliminated Cd sorption because of complexation and cationic competition. Cadmium would be considered as either mobile or very mobile under these conditions. Lead was not soluble in the pH- 6.85 suspension. At pH 12, the approximate pH of water in contact with flue gas-scrubber fly ash, Cd was essentially insoluble and Pb occurred as anionic Pb hydroxide. Anionic Pb was sorbed by the two clays, and the extent of sorption was not influenced by Cl or carbonate complexation. Sorption constants, derived from isotherms, suggested that Pb would be relatively immobile in saturated soil-water systems. The recent concern that highly alkaline, flue gas-scrubber fly ash may release environmentally significant concentrations of mobile Pb when placed in an ash-disposal site with a soil liner should be reevaluated in light of this study.

Discussion on 'characteristics of fly ashes from full-scale coal-fired power plants and their relationship to mercury adsorption' by Lu et al.

DOE Office of Scientific and Technical Information (OSTI.GOV)

James C. Hower; Bruno Valentim; Irena J. Kostova

2008-03-15

Mercury capture by coal-combustion fly ash is a function of the amount of Hg in the feed coal, the amount of carbon in the fly ash, the type of carbon in the fly ash (including variables introduced by the rank of the feed coal), and the flue gas temperature at the point of ash collection. In their discussion of fly ash and Hg adsorption, Lu et al. (Energy Fuels 2007, 21, 2112-2120) had some fundamental flaws in their techniques, which, in turn, impact the validity of analyzed parameters. First, they used mechanical sieving to segregate fly ash size fractions. Mechanicalmore » sieving does not produce representative size fractions, particularly for the finest sizes. If the study samples were not obtained correctly, the subsequent analyses of fly ash carbon and Hg cannot accurately represent the size fractions. In the analysis of carbon forms, it is not possible to accurately determine the forms with scanning electron microscopy. The complexity of the whole particles is overlooked when just examining the outer particle surface. Examination of elements such as Hg, present in very trace quantities in most fly ashes, requires careful attention to the analytical techniques. 36 refs., 3 figs., 1 tab.« less

Personal Flying Accident Rates of Selected Light Sport Aircraft Compared with General Aviation Aircraft.

PubMed

Mills, William D; DeJohn, Charles A

2016-07-01

The issue of expanding flight privileges that do not require medical oversight is currently an important topic, especially in the United States. We compared personal flying accident rates in aircraft with special light sport aircraft (SLSA) and experimental light sport aircraft (ELSA) airworthiness certificates to accident rates for personal flying in other general aviation (GA) aircraft. To calculate accident rates, personal flying hours were obtained from the annual FAA General Aviation and Part 135 Activity Surveys, and numbers of personal flying accidents were obtained from the NTSB accident database. Overall and fatal personal flying accident rates for the SLSA and ELSA groups and other GA aircraft were calculated and accident rates were compared. The overall personal flying accident rate for SLSA and ELSA was found to be 29.8 per 100,000 flight hours and the fatal accident rate was 5.2 per 100,000 flying hours. These are both significantly greater than the overall personal flying rate of 12.7 per 100,000 h and fatal rate of 2.6 per 100,000 h for other GA aircraft. Although this study has several limitations, the significantly higher accident rates in the sport pilot aircraft suggests caution when expanding sport pilot privileges to include larger, more complex aircraft. Mills WD, DeJohn CA. Personal flying accident rates of selected light sport aircraft compared with general aviation aircraft. Aerosp Med Hum Perform. 2016; 87(7):652-654.

Structure and Function of the Bi-Directional Bacterial Flagellar Motor

PubMed Central

Morimoto, Yusuke V.; Minamino, Tohru

2014-01-01

The bacterial flagellum is a locomotive organelle that propels the bacterial cell body in liquid environments. The flagellum is a supramolecular complex composed of about 30 different proteins and consists of at least three parts: a rotary motor, a universal joint, and a helical filament. The flagellar motor of Escherichia coli and Salmonella enterica is powered by an inward-directed electrochemical potential difference of protons across the cytoplasmic membrane. The flagellar motor consists of a rotor made of FliF, FliG, FliM and FliN and a dozen stators consisting of MotA and MotB. FliG, FliM and FliN also act as a molecular switch, enabling the motor to spin in both counterclockwise and clockwise directions. Each stator is anchored to the peptidoglycan layer through the C-terminal periplasmic domain of MotB and acts as a proton channel to couple the proton flow through the channel with torque generation. Highly conserved charged residues at the rotor–stator interface are required not only for torque generation but also for stator assembly around the rotor. In this review, we will summarize our current understanding of the structure and function of the proton-driven bacterial flagellar motor. PMID:24970213

Structure and function of the bi-directional bacterial flagellar motor.

PubMed

Morimoto, Yusuke V; Minamino, Tohru

2014-02-18

The bacterial flagellum is a locomotive organelle that propels the bacterial cell body in liquid environments. The flagellum is a supramolecular complex composed of about 30 different proteins and consists of at least three parts: a rotary motor, a universal joint, and a helical filament. The flagellar motor of Escherichia coli and Salmonella enterica is powered by an inward-directed electrochemical potential difference of protons across the cytoplasmic membrane. The flagellar motor consists of a rotor made of FliF, FliG, FliM and FliN and a dozen stators consisting of MotA and MotB. FliG, FliM and FliN also act as a molecular switch, enabling the motor to spin in both counterclockwise and clockwise directions. Each stator is anchored to the peptidoglycan layer through the C-terminal periplasmic domain of MotB and acts as a proton channel to couple the proton flow through the channel with torque generation. Highly conserved charged residues at the rotor-stator interface are required not only for torque generation but also for stator assembly around the rotor. In this review, we will summarize our current understanding of the structure and function of the proton-driven bacterial flagellar motor.

Description of evandromyia spelunca, a new phlebotomine species of the cortelezzii complex, from a cave in Minas Gerais State, Brazil (Diptera: Psychodidae: Phlebotominae)

PubMed Central

2011-01-01

Background The cave fauna of the Brazil is poorly documented, and among the insects those live or frequent caves and their adjacent environments phlebotomine sand flies call for special attention because several species are vectors of pathogens among vertebrates hosts. A new species of sand fly from Minas Gerais is described based in females and males collected in a cave of the municipality of Lassance. Results The morphological characters of the new species permit to include in the Evandromyia genus, cortelezzii complex. This complex consists of three species: Evandromyia corumbaensis (Galati, Nunes, Oshiro & Rego, 1989), Evandromyia cortelezzii (Brethes, 1923) and Evandromyia sallesi (Galvao & Coutinho, 1940). Conclusions The new species can be separate from the others of the cortelezzii complex through morphological characters of the male terminalia and female spermathecae. PMID:21827682

Why a fly? Using Drosophila to understand the genetics of circadian rhythms and sleep.

PubMed

Hendricks, Joan C; Sehgal, Amita

2004-03-15

Among simple model systems, Drosophila has specific advantages for neurobehavioral investigations. It has been particularly useful for understanding the molecular basis of circadian rhythms. In addition, the genetics of fruit-fly sleep are beginning to develop. This review summarizes the current state of understanding of circadian rhythms and sleep in the fruit fly for the readers of Sleep. We note where information is available in mammals, for comparison with findings in fruit flies, to provide an evolutionary perspective, and we focus on recent findings and new questions. We propose that sleep-specific neural activity may alter cellular function and thus accomplish the restorative function or functions of sleep. In conclusion, we sound some cautionary notes about some of the complexities of working with this "simple" organism.

Reliability/safety analysis of a fly-by-wire system

NASA Technical Reports Server (NTRS)

Brock, L. D.; Goddman, H. A.

1980-01-01

An analysis technique has been developed to estimate the reliability of a very complex, safety-critical system by constructing a diagram of the reliability equations for the total system. This diagram has many of the characteristics of a fault-tree or success-path diagram, but is much easier to construct for complex redundant systems. The diagram provides insight into system failure characteristics and identifies the most likely failure modes. A computer program aids in the construction of the diagram and the computation of reliability. Analysis of the NASA F-8 Digital Fly-by-Wire Flight Control System is used to illustrate the technique.

Dembo polymerase chain reaction technique for detection of bovine abortion, diarrhea, and respiratory disease complex infectious agents in potential vectors and reservoirs.

PubMed

Rahpaya, Sayed Samim; Tsuchiaka, Shinobu; Kishimoto, Mai; Oba, Mami; Katayama, Yukie; Nunomura, Yuka; Kokawa, Saki; Kimura, Takashi; Kobayashi, Atsushi; Kirino, Yumi; Okabayashi, Tamaki; Nonaka, Nariaki; Mekata, Hirohisa; Aoki, Hiroshi; Shiokawa, Mai; Umetsu, Moeko; Morita, Tatsushi; Hasebe, Ayako; Otsu, Keiko; Asai, Tetsuo; Yamaguchi, Tomohiro; Makino, Shinji; Murata, Yoshiteru; Abi, Ahmad Jan; Omatsu, Tsutomu; Mizutani, Tetsuya

2018-05-31

Bovine abortion, diarrhea, and respiratory disease complexes, caused by infectious agents, result in high and significant economic losses for the cattle industry. These pathogens are likely transmitted by various vectors and reservoirs including insects, birds, and rodents. However, experimental data supporting this possibility are scarce. We collected 117 samples and screened them for 44 bovine abortive, diarrheal, and respiratory disease complex pathogens by using Dembo polymerase chain reaction (PCR), which is based on TaqMan real-time PCR. Fifty-seven samples were positive for at least one pathogen, including bovine viral diarrhea virus, bovine enterovirus, Salmonella enterica ser. Dublin, Salmonella enterica ser. Typhimurium, and Neospora caninum ; some samples were positive for multiple pathogens. Bovine viral diarrhea virus and bovine enterovirus were the most frequently detected pathogens, especially in flies, suggesting an important role of flies in the transmission of these viruses. Additionally, we detected the N. caninum genome from a cockroach sample for the first time. Our data suggest that insects (particularly flies), birds, and rodents are potential vectors and reservoirs of abortion, diarrhea, and respiratory infectious agents, and that they may transmit more than one pathogen at the same time.

Drosophila Torsin Protein Regulates Motor Control and Stress Sensitivity and Forms a Complex with Fragile-X Mental Retardation Protein

PubMed Central

Ahn, Hyo-Min; Koh, Young Ho

2016-01-01

We investigated unknown in vivo functions of Torsin by using Drosophila as a model. Downregulation of Drosophila Torsin (DTor) by DTor-specific inhibitory double-stranded RNA (RNAi) induced abnormal locomotor behavior and increased susceptibility to H2O2. In addition, altered expression of DTor significantly increased the numbers of synaptic boutons. One important biochemical consequence of DTor-RNAi expression in fly brains was upregulation of alcohol dehydrogenase (ADH). Altered expression of ADH has also been reported in Drosophila Fragile-X mental retardation protein (DFMRP) mutant flies. Interestingly, expression of DFMRP was altered in DTor mutant flies, and DTor and DFMRP were present in the same protein complexes. In addition, DTor and DFMRP immunoreactivities were partially colocalized in several cellular organelles in larval muscles. Furthermore, there were no significant differences between synaptic morphologies of dfmrp null mutants and dfmrp mutants expressing DTor-RNAi. Taken together, our evidences suggested that DTor and DFMRP might be present in the same signaling pathway regulating synaptic plasticity. In addition, we also found that human Torsin1A and human FMRP were present in the same protein complexes, suggesting that this phenomenon is evolutionarily conserved. PMID:27313903

Molecular Detection of Leishmania DNA in Wild-Caught Phlebotomine Sand Flies (Diptera: Psychodidae) From a Cave in the State of Minas Gerais, Brazil.

PubMed

Carvalho, G M L; Brazil, R P; Rêgo, F D; Ramos, M C N F; Zenóbio, A P L A; Andrade Filho, J D

2017-01-01

Leishmania spp. are distributed throughout the world, and different species are associated with varying degrees of disease severity. In Brazil, Leishmania transmission involves several species of phlebotomine sand flies that are closely associated with different parasites and reservoirs, and thereby giving rise to different transmission cycles. Infection occurs during the bloodmeals of sand flies obtained from a variety of wild and domestic animals, and sometimes from humans. The present study focused on detection of Leishmania DNA in phlebotomine sand flies from a cave in the state of Minas Gerais. Detection of Leishmania in female sand flies was performed with ITS1 PCR-RFLP (internal transcribed spacer 1) using HaeIII enzyme and genetic sequencing for SSUrRNA target. The survey of Leishmania DNA was carried out on 232 pools and the parasite DNA was detected in four: one pool of Lutzomyia cavernicola (Costa Lima, 1932), infected with Le. infantum (ITS1 PCR-RFLP), two pools of Evandromyia sallesi (Galvão & Coutinho, 1939), both infected with Leishmania braziliensis complex (SSUrRNA genetic sequencing analysis), and one pool of Sciopemyia sordellii (Shannon & Del Ponte, 1927), infected with subgenus Leishmania (SSUrRNA genetic sequencing analysis). The present study identified the species for Leishmania DNA detected in four pools of sand flies, all of which were captured inside the cave. These results represent the first molecular detection of Lu cavernicola with Le infantum DNA, Sc sordellii with subgenus Leishmania DNA, and Ev sallesi with Leishmania braziliensis complex DNA. The infection rate in females captured for this study was 0.17%. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

An unsupervised method for quantifying the behavior of paired animals

NASA Astrophysics Data System (ADS)

Klibaite, Ugne; Berman, Gordon J.; Cande, Jessica; Stern, David L.; Shaevitz, Joshua W.

2017-02-01

Behaviors involving the interaction of multiple individuals are complex and frequently crucial for an animal’s survival. These interactions, ranging across sensory modalities, length scales, and time scales, are often subtle and difficult to characterize. Contextual effects on the frequency of behaviors become even more difficult to quantify when physical interaction between animals interferes with conventional data analysis, e.g. due to visual occlusion. We introduce a method for quantifying behavior in fruit fly interaction that combines high-throughput video acquisition and tracking of individuals with recent unsupervised methods for capturing an animal’s entire behavioral repertoire. We find behavioral differences between solitary flies and those paired with an individual of the opposite sex, identifying specific behaviors that are affected by social and spatial context. Our pipeline allows for a comprehensive description of the interaction between two individuals using unsupervised machine learning methods, and will be used to answer questions about the depth of complexity and variance in fruit fly courtship.

Nonlinear circuits for naturalistic visual motion estimation

PubMed Central

Fitzgerald, James E; Clark, Damon A

2015-01-01

Many animals use visual signals to estimate motion. Canonical models suppose that animals estimate motion by cross-correlating pairs of spatiotemporally separated visual signals, but recent experiments indicate that humans and flies perceive motion from higher-order correlations that signify motion in natural environments. Here we show how biologically plausible processing motifs in neural circuits could be tuned to extract this information. We emphasize how known aspects of Drosophila's visual circuitry could embody this tuning and predict fly behavior. We find that segregating motion signals into ON/OFF channels can enhance estimation accuracy by accounting for natural light/dark asymmetries. Furthermore, a diversity of inputs to motion detecting neurons can provide access to more complex higher-order correlations. Collectively, these results illustrate how non-canonical computations improve motion estimation with naturalistic inputs. This argues that the complexity of the fly's motion computations, implemented in its elaborate circuits, represents a valuable feature of its visual motion estimator. DOI: http://dx.doi.org/10.7554/eLife.09123.001 PMID:26499494

Morphometric study of third-instar larvae from five morphotypes of the Anastrepha fraterculus cryptic species complex (Diptera, Tephritidae)

PubMed Central

Canal, Nelson A.; Hernández-Ortiz, Vicente; Salas, Juan O. Tigrero; Selivon, Denise

2015-01-01

Abstract The occurrence of cryptic species among economically important fruit flies strongly affects the development of management tactics for these pests. Tools for studying cryptic species not only facilitate evolutionary and systematic studies, but they also provide support for fruit fly management and quarantine activities. Previous studies have shown that the South American fruit fly, Anastrepha fraterculus, is a complex of cryptic species, but few studies have been performed on the morphology of its immature stages. An analysis of mandible shape and linear morphometric variability was applied to third-instar larvae of five morphotypes of the Anastrepha fraterculus complex: Mexican, Andean, Ecuadorian, Peruvian and Brazilian-1. Outline geometric morphometry was used to study the mouth hook shape and linear morphometry analysis was performed using 24 linear measurements of the body, cephalopharyngeal skeleton, mouth hook and hypopharyngeal sclerite. Different morphotypes were grouped accurately using canonical discriminant analyses of both the geometric and linear morphometry. The shape of the mandible differed among the morphotypes, and the anterior spiracle length, number of tubules of the anterior spiracle, length and height of the mouth hook and length of the cephalopharyngeal skeleton were the most significant variables in the linear morphometric analysis. Third-instar larvae provide useful characters for studies of cryptic species in the Anastrepha fraterculus complex. PMID:26798253

HTV-4 undocking

NASA Image and Video Library

2013-09-04

One of the Expedition 36 crew members aboard the International Space Station took this picture of the Japanese HTV-4 unmanned cargo spacecraft,backdropped against the Earth,following its unberthing and release from the orbital outpost. HTV-4,after backing away from the flying complex,headed for re-entry into Earth's atmosphere,burning upon re-entry. Per Twitter message: And, shortly after release of #HTV4, flying over Africa (The storm clouds were amazing).

Acoustic signals in the sand fly Lutzomyia (Nyssomyia) intermedia (Diptera: Psychodidae)

PubMed Central

2011-01-01

Background Acoustic signals are part of the courtship of many insects and they often act as species-specific signals that are important in the reproductive isolation of closely related species. Here we report the courtship songs of the sand fly Lutzomyia (Nyssomyia) intermedia, one of the main vectors of cutaneous leishmaniasis in Brazil. Findings Recordings were performed using insects from three localities from Eastern Brazil: Posse and Jacarepaguá in Rio de Janeiro State and Corte de Pedra in Bahia State. The three areas have remnants of the Brazilian Atlantic forest, they are endemic for cutaneous leishmaniasis and L. intermedia is the predominant sand fly species. We observed that during courtship L. intermedia males from all populations produced pulse songs consisting of short trains. No significant differences in song parameters were observed between the males of the three localities. Conclusions L. intermedia males produce acoustic signals as reported for some other sand flies such as the sibling species of the Lutzomyia longipalpis complex. The lack of differences between the males from the three localities is consistent with previous molecular studies of the period gene carried out in the same populations, reinforcing the idea that L. intermedia is not a species complex in the studied areas and that the three populations are likely to have similar vectorial capacities. PMID:21569534

Acoustic signals in the sand fly Lutzomyia (Nyssomyia) intermedia (Diptera: Psychodidae).

PubMed

Vigoder, Felipe M; Souza, Nataly A; Peixoto, Alexandre A

2011-05-13

Acoustic signals are part of the courtship of many insects and they often act as species-specific signals that are important in the reproductive isolation of closely related species. Here we report the courtship songs of the sand fly Lutzomyia (Nyssomyia) intermedia, one of the main vectors of cutaneous leishmaniasis in Brazil. Recordings were performed using insects from three localities from Eastern Brazil: Posse and Jacarepaguá in Rio de Janeiro State and Corte de Pedra in Bahia State. The three areas have remnants of the Brazilian Atlantic forest, they are endemic for cutaneous leishmaniasis and L. intermedia is the predominant sand fly species. We observed that during courtship L. intermedia males from all populations produced pulse songs consisting of short trains. No significant differences in song parameters were observed between the males of the three localities. L. intermedia males produce acoustic signals as reported for some other sand flies such as the sibling species of the Lutzomyia longipalpis complex. The lack of differences between the males from the three localities is consistent with previous molecular studies of the period gene carried out in the same populations, reinforcing the idea that L. intermedia is not a species complex in the studied areas and that the three populations are likely to have similar vectorial capacities.

Radiation factors in space and a system for their monitoring.

PubMed

Kovtunenko, V M; Kremnev, R S; Pichkhadze, K M; Bogomolov, V B; Kontor, N N; Filippichev, S A; Petrov, V M; Pissarenko, N F

1994-10-01

The radiation environment is of special concern when the spaceship flies in deep space. The annual fluence of the galactic cosmic rays is approximately 10(8) cm-2 and the absorbed dose of the solar cosmic rays can reach 10 Gy per event behind the shielding thickness of 3-5 g cm-2 Al. For the radiation environment monitoring it is planned to place a measuring complex on the space probes "Mars" and "Spectr" flying outside the magnetosphere. This complex is to measure: cosmic rays composition, particle flux, dose equivalent, energy and LET spectra, solar X-rays spectrum. On line data transmission by the space probes permits to obtain the radiation environment data in space.

Leishmania, microbiota and sand fly immunity.

PubMed

Telleria, Erich Loza; Martins-da-Silva, Andrea; Tempone, Antonio Jorge; Traub-Csekö, Yara Maria

2018-06-20

In this review, we explore the state-of-the-art of sand fly relationships with microbiota, viruses and Leishmania, with particular emphasis on the vector immune responses. Insect-borne diseases are a major public health problem in the world. Phlebotomine sand flies are proven vectors of several aetiological agents including viruses, bacteria and the trypanosomatid Leishmania, which are responsible for diseases such as viral encephalitis, bartonellosis and leishmaniasis, respectively. All metazoans in nature coexist intimately with a community of commensal microorganisms known as microbiota. The microbiota has a fundamental role in the induction, maturation and function of the host immune system, which can modulate host protection from pathogens and infectious diseases. We briefly review viruses of public health importance present in sand flies and revisit studies done on bacterial and fungal gut contents of these vectors. We bring this information into the context of sand fly development and immune responses. We highlight the immunity mechanisms that the insect utilizes to survive the potential threats involved in these interactions and discuss the recently discovered complex interactions among microbiota, sand fly, Leishmania and virus. Additionally, some of the alternative control strategies that could benefit from the current knowledge are considered.

Extension of Drosophila Lifespan by Rhodiola rosea Depends on Dietary Carbohydrate and Caloric Content in a Simplified Diet.

PubMed

Schriner, Samuel E; Coskun, Volkan; Hogan, Sean P; Nguyen, Cindy T; Lopez, Terry E; Jafari, Mahtab

2016-03-01

The root and rhizome extract of Rhodiola rosea has been extensively used in traditional medicine to improve physical and mental performance and to protect against stress. We, and others, have reported that R. rosea can extend lifespan in flies, worms, and yeast. We also previously found that the extract can act independently of dietary restriction (DR), a treatment that can extend lifespan in a range of model organisms. In flies, DR is implemented through a reduction in dietary yeast content. Here, we report that the ability of R. rosea extract to extend lifespan in flies is dependent on the carbohydrate and caloric content when supplemented with a simplified diet composed of yeast and sucrose. R. rosea extract elevated the sugar content in flies and down-regulated hexokinase expression, suggesting that it perturbs carbohydrate metabolism in flies. In our previous studies, bananas, barley malt, and corn syrup provided dietary carbohydrates, and R. rosea extract could extend lifespan with a range of caloric levels. We conclude that the lifespan-extending effect of R. rosea extract in flies is dependent on dietary carbohydrate and caloric contents coupled with an interaction with complex dietary components present in bananas, barley, or corn.

Unmasking the complexity of species identification in Australasian flying-foxes

PubMed Central

Danks, Melissa; Lott, Matthew J.; Dennison, Siobhan; Frankham, Greta J.; King, Andrew; Eldridge, Mark D. B.; Johnson, Rebecca N.; Divljan, Anja

2018-01-01

Pteropus (flying-foxes) are a speciose group of non-echolocating large bats, with five extant Australian species and 24 additional species distributed amongst the Pacific Islands. In 2015, an injured flying-fox with unusual facial markings was found in Sydney, Australia, following severe and widespread storms. Based on an initial assessment, the individual belonged to Pteropus but could not be readily identified to species. As a consequence, four hypotheses for its identification/origin were posited: the specimen represented (1) an undescribed Australian species; or (2) a morphological variant of a recognised Australian species; or (3) a hybrid individual; or (4) a vagrant from the nearby Southwest Pacific Islands. We used a combination of morphological and both mitochondrial- and nuclear DNA-based identification methods to assess these hypotheses. Based on the results, we propose that this morphologically unique Pteropus most likely represents an unusual P. alecto (black flying-fox) potentially resulting from introgression from another Pteropus species. Unexpectedly, this individual, and the addition of reference sequence data from newly vouchered specimens, revealed a previously unreported P. alecto mitochondrial DNA lineage. This lineage was distinct from currently available haplotypes. It also suggests long-term hybridisation commonly occurs between P. alecto and P. conspicillatus (spectacled flying-fox). This highlights the importance of extensive reference data, and the inclusion of multiple vouchered specimens for each species to encompass both intraspecific and interspecific variation to provide accurate and robust species identification. Moreover, our additional reference data further demonstrates the complexity of Pteropus species relationships, including hybridisation, and potential intraspecific biogeographical structure that may impact on their management and conservation. PMID:29634748

How to Design a Genetic Mating Scheme: A Basic Training Package for Drosophila Genetics

PubMed Central

Roote, John; Prokop, Andreas

2013-01-01

Drosophila melanogaster is a powerful model organism for biological research. The essential and common instrument of fly research is genetics, the art of applying Mendelian rules in the specific context of Drosophila with its unique classical genetic tools and the breadth of modern genetic tools and strategies brought in by molecular biology, transgenic technologies and the use of recombinases. Training newcomers to fly genetics is a complex and time-consuming task but too important to be left to chance. Surprisingly, suitable training resources for beginners currently are not available. Here we provide a training package for basic Drosophila genetics, designed to ensure that basic knowledge on all key areas is covered while reducing the time invested by trainers. First, a manual introduces to fly history, rationale for mating schemes, fly handling, Mendelian rules in fly, markers and balancers, mating scheme design, and transgenic technologies. Its self-study is followed by a practical training session on gender and marker selection, introducing real flies under the dissecting microscope. Next, through self-study of a PowerPoint presentation, trainees are guided step-by-step through a mating scheme. Finally, to consolidate knowledge, trainees are asked to design similar mating schemes reflecting routine tasks in a fly laboratory. This exercise requires individual feedback but also provides unique opportunities for trainers to spot weaknesses and strengths of each trainee and take remedial action. This training package is being successfully applied at the Manchester fly facility and may serve as a model for further training resources covering other aspects of fly research. PMID:23390611

Position-effect variegation revisited: HUSHing up heterochromatin in human cells.

PubMed

Timms, Richard T; Tchasovnikarova, Iva A; Lehner, Paul J

2016-04-01

Much of what we understand about heterochromatin formation in mammals has been extrapolated from forward genetic screens for modifiers of position-effect variegation (PEV) in the fruit fly Drosophila melanogaster. The recent identification of the HUSH (Human Silencing Hub) complex suggests that more recent evolutionary developments contribute to the mechanisms underlying PEV in human cells. Although HUSH-mediated repression also involves heterochromatin spreading through the reading and writing of the repressive H3K9me3 histone modification, clear orthologues of HUSH subunits are not found in Drosophila but are conserved in vertebrates. Here we compare the insights into the mechanisms of PEV derived from genetic screens in the fly, the mouse and in human cells, review what is currently known about the HUSH complex and discuss the implications of HUSH-mediated silencing for viral latency. Future studies will provide mechanistic insight into HUSH complex function and reveal the relationship between HUSH and other epigenetic silencing complexes. © 2016 WILEY Periodicals, Inc.

Parasites of parasites of bats: Laboulbeniales (Fungi: Ascomycota) on bat flies (Diptera: Nycteribiidae) in central Europe.

PubMed

Haelewaters, Danny; Pfliegler, Walter P; Szentiványi, Tamara; Földvári, Mihály; Sándor, Attila D; Barti, Levente; Camacho, Jasmin J; Gort, Gerrit; Estók, Péter; Hiller, Thomas; Dick, Carl W; Pfister, Donald H

2017-02-21

Bat flies (Streblidae and Nycteribiidae) are among the most specialized families of the order Diptera. Members of these two related families have an obligate ectoparasitic lifestyle on bats, and they are known disease vectors for their hosts. However, bat flies have their own ectoparasites: fungi of the order Laboulbeniales. In Europe, members of the Nycteribiidae are parasitized by four species belonging to the genus Arthrorhynchus. We carried out a systematic survey of the distribution and fungus-bat fly associations of the genus in central Europe (Hungary, Romania). We encountered the bat fly Nycteribia pedicularia and the fungus Arthrorhynchus eucampsipodae as new country records for Hungary. The following bat-bat fly associations are for the first time reported: Nycteribia kolenatii on Miniopterus schreibersii, Myotis blythii, Myotis capaccinii and Rhinolophus ferrumequinum; Penicillidia conspicua on Myotis daubentonii; and Phthiridium biarticulatum on Myotis capaccinii. Laboulbeniales infections were found on 45 of 1,494 screened bat flies (3.0%). We report two fungal species: Arthrorhynchus eucampsipodae on Nycteribia schmidlii, and A. nycteribiae on N. schmidlii, Penicillidia conspicua, and P. dufourii. Penicillidia conspicua was infected with Laboulbeniales most frequently (25%, n = 152), followed by N. schmidlii (3.1%, n = 159) and P. dufourii (2.0%, n = 102). Laboulbeniales seem to prefer female bat fly hosts to males. We think this might be due to a combination of factors: female bat flies have a longer life span, while during pregnancy female bat flies are significantly larger than males and accumulate an excess of fat reserves. Finally, ribosomal DNA sequences for A. nycteribiae are presented. We screened ectoparasitic bat flies from Hungary and Romania for the presence of ectoparasitic Laboulbeniales fungi. Arthrorhynchus eucampsipodae and A. nycteribiae were found on three species of bat flies. This study extends geographical and host ranges of both bat flies and Laboulbeniales fungi. The sequence data generated in this work contribute to molecular phylogenetic studies of the order Laboulbeniales. Our survey shows a complex network of bats, bat flies and Laboulbeniales fungi, of which the hyperparasitic fungi are rare and species-poor. Their host insects, on the other hand, are relatively abundant and diverse.

Multiple leading edge vortices of unexpected strength in freely flying hawkmoth

PubMed Central

Johansson, L. Christoffer; Engel, Sophia; Kelber, Almut; Heerenbrink, Marco Klein; Hedenström, Anders

2013-01-01

The Leading Edge Vortex (LEV) is a universal mechanism enhancing lift in flying organisms. LEVs, generally illustrated as a single vortex attached to the wing throughout the downstroke, have not been studied quantitatively in freely flying insects. Previous findings are either qualitative or from flappers and tethered insects. We measure the flow above the wing of freely flying hawkmoths and find multiple simultaneous LEVs of varying strength and structure along the wingspan. At the inner wing there is a single, attached LEV, while at mid wing there are multiple LEVs, and towards the wingtip flow separates. At mid wing the LEV circulation is ~40% higher than in the wake, implying that the circulation unrelated to the LEV may reduce lift. The strong and complex LEV suggests relatively high flight power in hawmoths. The variable LEV structure may result in variable force production, influencing flight control in the animals. PMID:24253180

An Insight into the Sialotranscriptome of Simulium nigrimanum, a Black Fly Associated with Fogo Selvagem in South America

PubMed Central

Ribeiro, José M. C.; Valenzuela, Jesus G.; Pham, Van M.; Kleeman, Lindsay; Barbian, Kent D.; Favreau, Amanda J.; Eaton, Donald P.; Aoki, Valeria; Hans-Filho, Gunter; Rivitti, Evandro A.; Diaz, Luis A.

2010-01-01

Pemphigus foliaceus is a life threatening skin disease that is associated with autoimmunity to desmoglein, a skin protein involved in the adhesion of keratinocytes. This disease is endemic in certain areas of South America, suggesting the mediation of environmental factors triggering autoimmunity. Among the possible environmental factors, exposure to bites of black flies, in particular Simulium nigrimanum has been suggested. In this work, we describe the sialotranscriptome of adult female S. nigrimanum flies. It reveals the complexity of the salivary potion of this insect, comprised by over 70 distinct genes within over 30 protein families, including several novel families, even when compared with the previously described sialotranscriptome of the autogenous black fly, S. vittatum. The uncovering of this sialotranscriptome provides a platform for testing pemphigus patient sera against recombinant salivary proteins from S. nigrimanum and for the discovery of novel pharmacologically active compounds. PMID:20519601

Neural Circuits Underlying Fly Larval Locomotion

PubMed Central

Kohsaka, Hiroshi; Guertin, Pierre A.; Nose, Akinao

2017-01-01

Locomotion is a complex motor behavior that may be expressed in different ways using a variety of strategies depending upon species and pathological or environmental conditions. Quadrupedal or bipedal walking, running, swimming, flying and gliding constitute some of the locomotor modes enabling the body, in all cases, to move from one place to another. Despite these apparent differences in modes of locomotion, both vertebrate and invertebrate species share, at least in part, comparable neural control mechanisms for locomotor rhythm and pattern generation and modulation. Significant advances have been made in recent years in studies of the genetic aspects of these control systems. Findings made specifically using Drosophila (fruit fly) models and preparations have contributed to further understanding of the key role of genes in locomotion. This review focuses on some of the main findings made in larval fruit flies while briefly summarizing the basic advantages of using this powerful animal model for studying the neural locomotor system. PMID:27928962

The LSD1 Family of Histone Demethylases and the Pumilio Posttranscriptional Repressor Function in a Complex Regulatory Feedback Loop

PubMed Central

Miles, Wayne O.; Lepesant, Julie M. J.; Bourdeaux, Jessie; Texier, Manuela; Kerenyi, Marc A.; Nakakido, Makoto; Hamamoto, Ryuji; Orkin, Stuart H.; Dyson, Nicholas J.

2015-01-01

The lysine (K)-specific demethylase (LSD1) family of histone demethylases regulates chromatin structure and the transcriptional potential of genes. LSD1 is frequently deregulated in tumors, and depletion of LSD1 family members causes developmental defects. Here, we report that reductions in the expression of the Pumilio (PUM) translational repressor complex enhanced phenotypes due to dLsd1 depletion in Drosophila. We show that the PUM complex is a target of LSD1 regulation in fly and mammalian cells and that its expression is inversely correlated with LSD1 levels in human bladder carcinoma. Unexpectedly, we find that PUM posttranscriptionally regulates LSD1 family protein levels in flies and human cells, indicating the existence of feedback loops between the LSD1 family and the PUM complex. Our results highlight a new posttranscriptional mechanism regulating LSD1 activity and suggest that the feedback loop between the LSD1 family and the PUM complex may be functionally important during development and in human malignancies. PMID:26438601

Flying saucer1 is a transmembrane RING E3 ubiquitin ligase that regulates the degree of pectin methylesterification in Arabidopsis seed mucilage.

PubMed

Voiniciuc, Catalin; Dean, Gillian H; Griffiths, Jonathan S; Kirchsteiger, Kerstin; Hwang, Yeen Ting; Gillett, Alan; Dow, Graham; Western, Tamara L; Estelle, Mark; Haughn, George W

2013-03-01

Pectins are complex polysaccharides that form the gel matrix of the primary cell wall and are abundant in the middle lamella that holds plant cells together. Their degree of methylesterification (DM) impacts wall strength and cell adhesion since unesterified pectin regions can cross-link via Ca(2+) ions to form stronger gels. Here, we characterize flying saucer1 (fly1), a novel Arabidopsis thaliana seed coat mutant, which displays primary wall detachment, reduced mucilage extrusion, and increased mucilage adherence. These defects appear to result from a lower DM in mucilage and are enhanced by the addition of Ca(2+) or completely rescued using alkaline Ca(2+) chelators. FLY1 encodes a transmembrane protein with a RING-H2 domain that has in vitro E3 ubiquitin ligase activity. FLY1 is orthologous to TRANSMEMBRANE UBIQUITIN LIGASE1, a Golgi-localized E3 ligase involved in the quality control of membrane proteins in yeast. However, FLY1-yellow fluorescent protein (YFP) fusions are localized in punctae that are predominantly distinct from the Golgi and the trans-Golgi network/early endosome in the seed coat epidermis. Wortmannin treatment, which induces the fusion of late endosomes in plants, resulted in enlarged FLY1-YFP bodies. We propose that FLY1 regulates the DM of pectin in mucilage, potentially by recycling pectin methylesterase enzymes in the endomembrane system of seed coat epidermal cells.

FLYING SAUCER1 Is a Transmembrane RING E3 Ubiquitin Ligase That Regulates the Degree of Pectin Methylesterification in Arabidopsis Seed Mucilage[W

PubMed Central

Voiniciuc, Cătălin; Dean, Gillian H.; Griffiths, Jonathan S.; Kirchsteiger, Kerstin; Hwang, Yeen Ting; Gillett, Alan; Dow, Graham; Western, Tamara L.; Estelle, Mark; Haughn, George W.

2013-01-01

Pectins are complex polysaccharides that form the gel matrix of the primary cell wall and are abundant in the middle lamella that holds plant cells together. Their degree of methylesterification (DM) impacts wall strength and cell adhesion since unesterified pectin regions can cross-link via Ca2+ ions to form stronger gels. Here, we characterize flying saucer1 (fly1), a novel Arabidopsis thaliana seed coat mutant, which displays primary wall detachment, reduced mucilage extrusion, and increased mucilage adherence. These defects appear to result from a lower DM in mucilage and are enhanced by the addition of Ca2+ or completely rescued using alkaline Ca2+ chelators. FLY1 encodes a transmembrane protein with a RING-H2 domain that has in vitro E3 ubiquitin ligase activity. FLY1 is orthologous to TRANSMEMBRANE UBIQUITIN LIGASE1, a Golgi-localized E3 ligase involved in the quality control of membrane proteins in yeast. However, FLY1–yellow fluorescent protein (YFP) fusions are localized in punctae that are predominantly distinct from the Golgi and the trans-Golgi network/early endosome in the seed coat epidermis. Wortmannin treatment, which induces the fusion of late endosomes in plants, resulted in enlarged FLY1-YFP bodies. We propose that FLY1 regulates the DM of pectin in mucilage, potentially by recycling pectin methylesterase enzymes in the endomembrane system of seed coat epidermal cells. PMID:23482858

Bacterial flagella and Type III secretion: case studies in the evolution of complexity.

PubMed

Pallen, M J; Gophna, U

2007-01-01

Bacterial flagella at first sight appear uniquely sophisticated in structure, so much so that they have even been considered 'irreducibly complex' by the intelligent design movement. However, a more detailed analysis reveals that these remarkable pieces of molecular machinery are the product of processes that are fully compatible with Darwinian evolution. In this chapter we present evidence for such processes, based on a review of experimental studies, molecular phylogeny and microbial genomics. Several processes have played important roles in flagellar evolution: self-assembly of simple repeating subunits, gene duplication with subsequent divergence, recruitment of elements from other systems ('molecular bricolage'), and recombination. We also discuss additional tentative new assignments of homology (FliG with MgtE, FliO with YscJ). In conclusion, rather than providing evidence of intelligent design, flagellar and non-flagellar Type III secretion systems instead provide excellent case studies in the evolution of complex systems from simpler components.

Single-Molecule Analysis for RISC Assembly and Target Cleavage.

PubMed

Sasaki, Hiroshi M; Tadakuma, Hisashi; Tomari, Yukihide

2018-01-01

RNA-induced silencing complex (RISC) is a small RNA-protein complex that mediates silencing of complementary target RNAs. Biochemistry has been successfully used to characterize the molecular mechanism of RISC assembly and function for nearly two decades. However, further dissection of intermediate states during the reactions has been warranted to fill in the gaps in our understanding of RNA silencing mechanisms. Single-molecule analysis with total internal reflection fluorescence (TIRF) microscopy is a powerful imaging-based approach to interrogate complex formation and dynamics at the individual molecule level with high sensitivity. Combining this technique with our recently established in vitro reconstitution system of fly Ago2-RISC, we have developed a single-molecule observation system for RISC assembly. In this chapter, we summarize the detailed protocol for single-molecule analysis of chaperone-assisted assembly of fly Ago2-RISC as well as its target cleavage reaction.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Zhi-Hao; Zhao, Yue; Chen, Shui-Sheng

Seven new coordination polymers [Zn(H{sub 2}L)(mbdc)] (1), [Zn(H{sub 3}L)(btc)] (2), [Zn(H{sub 2}L)(Hbtc)] (3), [Zn(H{sub 2}L)(Hbtc)]·H{sub 2}O (4), [Zn{sub 2}(H{sub 2}L)(btc)(μ{sub 2}-OH)] (5), [Cd(H{sub 2}L)(mbdc)] (6) and [Cd{sub 3}(H{sub 2}L){sub 2}(btc){sub 2}(H{sub 2}O)]·5H{sub 2}O (7) were synthesized by reactions of the corresponding metal salt with rigid ligand 1,3-di(1H-imidazol-4-yl)benzene (H{sub 2}L) and different carboxylic acids of 1,3-benzenedicarboxylic acid (H{sub 2}mbdc) and benzene-1,3,5-tricarboxylic acid (H{sub 3}btc), respectively. The results of X-ray crystallographic analysis indicate that complex 1 is 1D chain while 2 is a (3,3)-connected 2D network with Point (Schläfli) symbol of (4,8{sup 2}). Complexes 3 and 6 are 2D networks, 4 ismore » a 3-fold interpenetrating 3D framework with Point (Schläfli) symbol of (6{sup 5},8) and 5 is a (3,8)-connected 2D network with Point (Schläfli) symbol of (3,4{sup 2}){sub 2}(3{sup 4},4{sup 6},5{sup 6},6{sup 8},7{sup 3},8), while 7 is a (3,10)-connected 3D net with Schläfli symbol of (3,4,5){sub 2}(3{sup 4},4{sup 8},5{sup 18},6{sup 12},7{sup 2},8). The thermal stability and photoluminescence of the complexes were investigated. Furthermore, DFT calculations were performed for 2–4 to discuss the temperature controlled self-assembly of the complexes. - Graphical abstract: Seven new coordination polymers with multicarboxylate and rigid ditopic 4-imidazole containing ligands have been obtained and found to show different structures and topologies. - Highlights: • Metal complexes with diverse structures of 1D chain, 2D network and 3D framework. • Mixed ligands of 1,3-di(1H-imidazol-4-yl)benzene and multicarboxylate. • Photoluminescence property.« less

Impact of phlebotomine sand flies on U.S. military operations at Tallil Air Base, Iraq: 4. Detection and identification of leishmania parasites in sand flies.

PubMed

Coleman, Russell E; Hochberg, Lisa P; Swanson, Katherine I; Lee, John S; McAvin, James C; Moulton, John K; Eddington, David O; Groebner, Jennifer L; O'Guinn, Monica L; Putnam, John L

2009-05-01

Sand flies collected between April 2003 and November 2004 at Tallil Air Base, Iraq, were evaluated for the presence of Leishmania parasites using a combination of a real-time Leishmania-generic polymerase chain reaction (PCR) assay and sequencing of a 360-bp fragment of the glucose-6-phosphate-isomerase (GPI) gene. A total of 2,505 pools containing 26,574 sand flies were tested using the real-time PCR assay. Leishmania DNA was initially detected in 536 pools; however, after extensive retesting with the real-time PCR assay, a total of 456 pools were considered positive and 80 were considered indeterminate. A total of 532 samples were evaluated for Leishmania GPI by sequencing, to include 439 PCR-positive samples, 80 PCR-indeterminate samples, and 13 PCR-negative samples. Leishmania GPI was detected in 284 samples that were sequenced, to include 281 (64%) of the PCR-positive samples and 3 (4%) of the PCR-indeterminate samples. Of the 284 sequences identified as Leishmania, 261 (91.9%) were L. tarentolae, 18 (6.3%) were L. donovani-complex parasites, 3 (1.1%) were L. tropica, and 2 were similar to both L. major and L. tropica. Minimum field infection rates were 0.09% for L. donovani-complex parasites, 0.02% for L. tropica, and 0.01% for the L. major/tropica-like parasite. Subsequent sequencing of a 600-bp region of the "Hyper" gene of 12 of the L. donovani-complex parasites showed that all 12 parasites were L. infantum. These data suggest that L. infantum was the primary leishmanial threat to U.S. military personnel deployed to Tallil Air Base. The implications of these findings are discussed.

The psychology of fear of flying (part I): a critical evaluation of current perspectives on the nature, prevalence and etiology of fear of flying.

PubMed

Oakes, Margaret; Bor, Robert

2010-11-01

Fear of flying, its nature, prevalence, etiology and treatment, has been the subject of a substantial quantity of research over the past 30 years. With the exception of a dated review of treatment methods however, there has been no evaluation of this expanding body of evidence, its contribution to theory and influence on clinical practice. Published research has also generally failed to apply developments in the understanding and treatment of anxiety disorders generally to fear of flying. This review provides a critical evaluation of the existing literature and what it reveals about theory and practice. It does this from the perspective of Cognitive Behavioural Therapy. The evidence reviewed demonstrates that fear of flying is a heterogeneous phenomenon which is acquired under the influence of complex psychological, social and physiological factors unique to each affected individual. Effective psychological interventions must therefore be founded on a comprehensive functional assessment of each individual, a finding which is considered in detail in the second part of this review. Copyright © 2010 Elsevier Ltd. All rights reserved.

Dietary glucose regulates yeast consumption in adult Drosophila males

PubMed Central

Lebreton, Sébastien; Witzgall, Peter; Olsson, Marie; Becher, Paul G.

2014-01-01

The adjustment of feeding behavior in response to hunger and satiety contributes to homeostatic regulation in animals. The fruit fly Drosophila melanogaster feeds on yeasts growing on overripe fruit, providing nutrients required for adult survival, reproduction and larval growth. Here, we present data on how the nutritional value of food affects subsequent yeast consumption in Drosophila adult males. After a period of starvation, flies showed intensive yeast consumption. In comparison, flies stopped feeding after having access to a nutritive cornmeal diet. Interestingly, dietary glucose was equally efficient as the complex cornmeal diet. In contrast, flies fed with sucralose, a non-metabolizable sweetener, behaved as if they were starved. The adipokinetic hormone and insulin-like peptides regulate metabolic processes in insects. We did not find any effect of the adipokinetic hormone pathway on this modulation. Instead, the insulin pathway was involved in these changes. Flies lacking the insulin receptor (InR) did not respond to nutrient deprivation by increasing yeast consumption. Together these results show the importance of insulin in the regulation of yeast consumption in response to starvation in adult D. melanogaster males. PMID:25566097

Dietary glucose regulates yeast consumption in adult Drosophila males.

PubMed

Lebreton, Sébastien; Witzgall, Peter; Olsson, Marie; Becher, Paul G

2014-01-01

The adjustment of feeding behavior in response to hunger and satiety contributes to homeostatic regulation in animals. The fruit fly Drosophila melanogaster feeds on yeasts growing on overripe fruit, providing nutrients required for adult survival, reproduction and larval growth. Here, we present data on how the nutritional value of food affects subsequent yeast consumption in Drosophila adult males. After a period of starvation, flies showed intensive yeast consumption. In comparison, flies stopped feeding after having access to a nutritive cornmeal diet. Interestingly, dietary glucose was equally efficient as the complex cornmeal diet. In contrast, flies fed with sucralose, a non-metabolizable sweetener, behaved as if they were starved. The adipokinetic hormone and insulin-like peptides regulate metabolic processes in insects. We did not find any effect of the adipokinetic hormone pathway on this modulation. Instead, the insulin pathway was involved in these changes. Flies lacking the insulin receptor (InR) did not respond to nutrient deprivation by increasing yeast consumption. Together these results show the importance of insulin in the regulation of yeast consumption in response to starvation in adult D. melanogaster males.

Drosophila model of Meier-Gorlin syndrome based on the mutation in a conserved C-Terminal domain of Orc6.

PubMed

Balasov, Maxim; Akhmetova, Katarina; Chesnokov, Igor

2015-11-01

Meier-Gorlin syndrome (MGS) is an autosomal recessive disorder characterized by microtia, primordial dwarfism, small ears, and skeletal abnormalities. Patients with MGS often carry mutations in the genes encoding the components of the pre-replicative complex such as Origin Recognition Complex (ORC) subunits Orc1, Orc4, Orc6, and helicase loaders Cdt1 and Cdc6. Orc6 is an important component of ORC and has functions in both DNA replication and cytokinesis. Mutation in conserved C-terminal motif of Orc6 associated with MGS impedes the interaction of Orc6 with core ORC. In order to study the effects of MGS mutation in an animal model system we introduced MGS mutation in Orc6 and established Drosophila model of MGS. Mutant flies die at third instar larval stage with abnormal chromosomes and DNA replication defects. The lethality can be rescued by elevated expression of mutant Orc6 protein. Rescued MGS flies are unable to fly and display multiple planar cell polarity defects. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

HTV-4 undocking

NASA Image and Video Library

2013-09-04

One of the Expedition 36 crew members aboard the International Space Station took this picture of the Japanese HTV-4 unmanned cargo spacecraft,backdropped against a land mass on Earth,following its unberthing but just prior to its release from the orbital outpost's Canadarm2. HTV-4,after backing away from the flying complex,headed for re-entry into Earth's atmosphere,burning upon re-entry. Per Twitter message: Flying over southwestern US, not long before release of #HTV4 by #Canadarm2.

FlyMine: an integrated database for Drosophila and Anopheles genomics

PubMed Central

Lyne, Rachel; Smith, Richard; Rutherford, Kim; Wakeling, Matthew; Varley, Andrew; Guillier, Francois; Janssens, Hilde; Ji, Wenyan; Mclaren, Peter; North, Philip; Rana, Debashis; Riley, Tom; Sullivan, Julie; Watkins, Xavier; Woodbridge, Mark; Lilley, Kathryn; Russell, Steve; Ashburner, Michael; Mizuguchi, Kenji; Micklem, Gos

2007-01-01

FlyMine is a data warehouse that addresses one of the important challenges of modern biology: how to integrate and make use of the diversity and volume of current biological data. Its main focus is genomic and proteomics data for Drosophila and other insects. It provides web access to integrated data at a number of different levels, from simple browsing to construction of complex queries, which can be executed on either single items or lists. PMID:17615057

Drosophila as an unconventional substrate for microfabrication

NASA Astrophysics Data System (ADS)

Shum, Angela J.; Parviz, Babak A.

2007-02-01

We present the application of Drosophila fruit flies as an unconventional substrate for microfabrication. Drosophila by itself represents a complex system capable of many functions not attainable with current microfabrication technology. By using Drosophila as a substrate, we are able to capitalize on these natural functions while incorporating additional functionality into a superior hybrid system. In the following, development of microfabrication processes for Drosophila substrates is discussed. In particular, results of a study on Drosophila tolerance to vacuum pressure during multiple stages of development are given. A remarkable finding that adult Drosophila may withstand up to 3 hours of exposure to vacuum with measurable survival is noted. This finding opens a number of new opportunities for performing fabrication processes, similar to the ones performed on a silicon wafer, on a fruit fly as a live substrate. As a model microfabrication process, it is shown how a collection of Drosophila can be made to self-assemble into an array of microfabricated recesses on a silicon wafer and how a shadow mask can be used to thermally evaporate 100 nm of indium on flies. The procedure resulted in the production of a number of live flies with a pre-designed metal micropattern on their wings. This demonstration of vacuum microfabrication on a live organism provides the first step towards the development of a hybrid biological/solid-state manufacturing process for complex microsystems.

Morphometric Differentiation Among Anastrepha fraterculus (Diptera: Tephritidae) Exploiting Sympatric Alternate Hosts.

PubMed

Gómez-Cendra, P V; Paulin, L E; Oroño, L; Ovruski, S M; Vilardi, J C

2016-04-01

Anastrepha fraterculus (Wiedemann) is currently considered a complex of cryptic species infesting fruits from Mexico to Argentina and represents an interesting biological model for evolutionary studies. Moreover, detecting and quantifying behavioral, morphological, and genetic differentiation among populations is also relevant to the application of environment-friendly control programs. Here, phenotypic differentiation among individuals coexisting in the wild in a Northern region of Argentina was unveiled and associated with host choice. Six morphometric traits were measured in sympatric flies exploiting three different host species. Phenotypic variation was shown to be host-dependent regardless of geographical or temporal overlap. Flies collected from synchronous alternate hosts (peach and walnut) differed from each other despite the lack of geographical isolation. By contrast, flies emerging from guavas that ripen about two months later than peach and walnut showed no significant differentiation in comparison to flies collected from walnuts, but they differ significantly from flies originating from peaches. This result is consistent with the hypothesis that the same population of flies shifts from walnuts to guavas throughout the year, whereas the population of flies that uses peaches as a host is probably exploiting other alternate hosts when peach availability decreases. Further research is needed to study the underlying mechanism. Results are consistent with previous molecular markers (inter-simple sequence repeat-ISSR) research on flies stemming from the same hosts and the same area, suggesting that differentiation among flies emerging from alternative hosts occurs at both genetic and phenotypic levels. The contribution of host preference in long-term genetic differentiation is discussed. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Object preference by walking fruit flies, Drosophila melanogaster, is mediated by vision and graviperception

PubMed Central

Robie, Alice A.; Straw, Andrew D.; Dickinson, Michael H.

2010-01-01

Walking fruit flies, Drosophila melanogaster, use visual information to orient towards salient objects in their environment, presumably as a search strategy for finding food, shelter or other resources. Less is known, however, about the role of vision or other sensory modalities such as mechanoreception in the evaluation of objects once they have been reached. To study the role of vision and mechanoreception in exploration behavior, we developed a large arena in which we could track individual fruit flies as they walked through either simple or more topologically complex landscapes. When exploring a simple, flat environment lacking three-dimensional objects, flies used visual cues from the distant background to stabilize their walking trajectories. When exploring an arena containing an array of cones, differing in geometry, flies actively oriented towards, climbed onto, and explored the objects, spending most of their time on the tallest, steepest object. A fly's behavioral response to the geometry of an object depended upon the intrinsic properties of each object and not a relative assessment to other nearby objects. Furthermore, the preference was not due to a greater attraction towards tall, steep objects, but rather a change in locomotor behavior once a fly reached and explored the surface. Specifically, flies are much more likely to stop walking for long periods when they are perched on tall, steep objects. Both the vision system and the antennal chordotonal organs (Johnston's organs) provide sufficient information about the geometry of an object to elicit the observed change in locomotor behavior. Only when both these sensory systems were impaired did flies not show the behavioral preference for the tall, steep objects. PMID:20581279

Detection flying aircraft from Landsat 8 OLI data

NASA Astrophysics Data System (ADS)

Zhao, F.; Xia, L.; Kylling, A.; Li, R. Q.; Shang, H.; Xu, Ming

2018-07-01

Monitoring flying aircraft from satellite data is important for evaluating the climate impact caused by the global aviation industry. However, due to the small size of aircraft and the complex surface types, it is almost impossible to identify aircraft from satellite data with moderate resolution, e.g. 30 m. In this study, the 1.38 μm water vapor absorption channel, often used for cirrus cloud or ash detection, is for the first time used to monitor flying aircraft from Landsat 8 data. The basic theory behind the detection of flying aircraft is that in the 1.38 μm channel most of the background reflectance between the ground and the aircraft is masked due to the strong water vapor absorption, while the signal of the flying aircraft will be attenuated less due to the low water vapor content between the satellite and the aircraft. A new composition of the Laplacian and Sobel operators for segmenting aircraft and other features were used to identify the flying aircraft. The Landsat 8 Operational Land Imager (OLI) 2.1 μm channel was used to make the method succeed under low vapor content. The accuracy assessment based on 65 Landsat 8 images indicated that the percentage of leakage is 3.18% and the percentage of false alarm is 0.532%.

Profiling of Human Acquired Immunity Against the Salivary Proteins of Phlebotomus papatasi Reveals Clusters of Differential Immunoreactivity

PubMed Central

Geraci, Nicholas S.; Mukbel, Rami M.; Kemp, Michael T.; Wadsworth, Mariha N.; Lesho, Emil; Stayback, Gwen M.; Champion, Matthew M.; Bernard, Megan A.; Abo-Shehada, Mahmoud; Coutinho-Abreu, Iliano V.; Ramalho-Ortigão, Marcelo; Hanafi, Hanafi A.; Fawaz, Emadeldin Y.; El-Hossary, Shabaan S.; Wortmann, Glenn; Hoel, David F.; McDowell, Mary Ann

2014-01-01

Phlebotomus papatasi sand flies are among the primary vectors of Leishmania major parasites from Morocco to the Indian subcontinent and from southern Europe to central and eastern Africa. Antibody-based immunity to sand fly salivary gland proteins in human populations remains a complex contextual problem that is not yet fully understood. We profiled the immunoreactivities of plasma antibodies to sand fly salivary gland sonicates (SGSs) from 229 human blood donors residing in different regions of sand fly endemicity throughout Jordan and Egypt as well as 69 US military personnel, who were differentially exposed to P. papatasi bites and L. major infections in Iraq. Compared with plasma from control region donors, antibodies were significantly immunoreactive to five salivary proteins (12, 26, 30, 38, and 44 kDa) among Jordanian and Egyptian donors, with immunoglobulin G4 being the dominant anti-SGS isotype. US personnel were significantly immunoreactive to only two salivary proteins (38 and 14 kDa). Using k-means clustering, donors were segregated into four clusters distinguished by unique immunoreactivity profiles to varying combinations of the significantly immunogenic salivary proteins. SGS-induced cellular proliferation was diminished among donors residing in sand fly-endemic regions. These data provide a clearer picture of human immune responses to sand fly vector salivary constituents. PMID:24615125

Metagenomic analysis reveals a functional signature for biomass degradation by cecal microbiota in the leaf-eating flying squirrel (Petaurista alborufus lena).

PubMed

Lu, Hsiao-Pei; Wang, Yu-bin; Huang, Shiao-Wei; Lin, Chung-Yen; Wu, Martin; Hsieh, Chih-hao; Yu, Hon-Tsen

2012-09-10

Animals co-evolve with their gut microbiota; the latter can perform complex metabolic reactions that cannot be done independently by the host. Although the importance of gut microbiota has been well demonstrated, there is a paucity of research regarding its role in foliage-foraging mammals with a specialized digestive system. In this study, a 16S rRNA gene survey and metagenomic sequencing were used to characterize genetic diversity and functional capability of cecal microbiota of the folivorous flying squirrel (Petaurista alborufus lena). Phylogenetic compositions of the cecal microbiota derived from 3 flying squirrels were dominated by Firmicutes. Based on end-sequences of fosmid clones from 1 flying squirrel, we inferred that microbial metabolism greatly contributed to intestinal functions, including degradation of carbohydrates, metabolism of proteins, and synthesis of vitamins. Moreover, 33 polysaccharide-degrading enzymes and 2 large genomic fragments containing a series of carbohydrate-associated genes were identified. Cecal microbiota of the leaf-eating flying squirrel have great metabolic potential for converting diverse plant materials into absorbable nutrients. The present study should serve as the basis for future investigations, using metagenomic approaches to elucidate the intricate mechanisms and interactions between host and gut microbiota of the flying squirrel digestive system, as well as other mammals with similar adaptations.

Drivers potentially influencing host-bat fly interactions in anthropogenic neotropical landscapes at different spatial scales.

PubMed

Hernández-Martínez, Jacqueline; Morales-Malacara, Juan B; Alvarez-Añorve, Mariana Yolotl; Amador-Hernández, Sergio; Oyama, Ken; Avila-Cabadilla, Luis Daniel

2018-05-21

The anthropogenic modification of natural landscapes, and the consequent changes in the environmental conditions and resources availability at multiple spatial scales can affect complex species interactions involving key-stone species such as bat-parasite interactions. In this study, we aimed to identify the drivers potentially influencing host-bat fly interactions at different spatial scales (at the host, vegetation stand and landscape level), in a tropical anthropogenic landscape. For this purpose, we mist-netted phyllostomid and moormopid bats and collected the bat flies (streblids) parasitizing them in 10 sites representing secondary and old growth forest. In general, the variation in fly communities largely mirrored the variation in bat communities as a result of the high level of specialization characterizing host-bat fly interaction networks. Nevertheless, we observed that: (1) bats roosting dynamics can shape bat-streblid interactions, modulating parasite prevalence and the intensity of infestation; (2) a degraded matrix could favor crowding and consequently the exchange of ectoparasites among bat species, lessening the level of specialization of the interaction networks and promoting novel interactions; and (3) bat-fly interaction can also be shaped by the dilution effect, as a decrease in bat diversity could be associated with a potential increase in the dissemination and prevalence of streblids.

Fly ash carbon burn-out at TVA`s Colbert and Shawnee Stations: Site specific application study. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cochran, J.W.; Kirkconnell, S.F.

1996-04-01

Many power plants, particularly after conversion to low-NOx burners, produce fly ash that is too high in carbon content to be successfully marketed as a concrete admixture. Fly ash beneficiation using Carbon Burn-Out (CBO) technology offers the opportunity to market fly ash that was previously landfilled. This site application study of beneficiating pulverized coal boiler fly ash at Tennessee Valley Authority`s Colbert and Shawnee Stations indicates this process is a cost effective solution for decreasing solid waste disposal, increasing landfill life, improving boiler heat rate, and generating a positive revenue stream. Results indicate that the Colbert Station has the flymore » ash market, site integration potential, and positive economics to support construction and operation of a CBO plant with an annual production rate of approximately 150,000 tons. As the market for fly ash increases, this capacity may be expanded to handle the majority of fly ash generated at Colbert. Results of the Shawnee Station analysis indicate that site integration constraints combined with the lack of near term local area fly ash market growth do not support construction and operation of a CBO plant. CBO commercial process design work in developing a generic commercial design resulted in a major improvement to the heat recovery portion of the process. This development resulted in the elimination of five major equipment items, with a corresponding reduction in plant complexity and costs. The design change is now considered part of the commercial offering.« less

A chemotactic signaling surface on CheY defined by suppressors of flagellar switch mutations.

PubMed Central

Roman, S J; Meyers, M; Volz, K; Matsumura, P

1992-01-01

CheY is the response regulator protein that interacts with the flagellar switch apparatus to modulate flagellar rotation during chemotactic signaling. CheY can be phosphorylated and dephosphorylated in vitro, and evidence indicates that CheY-P is the activated form that induces clockwise flagellar rotation, resulting in a tumble in the cell's swimming pattern. The flagellar switch apparatus is a complex macromolecular structure composed of at least three gene products, FliG, FliM, and FliN. Genetic analysis of Escherichia coli has identified fliG and fliM as genes in which mutations occur that allele specifically suppress cheY mutations, indicating interactions among these gene products. We have generated a class of cheY mutations selected for dominant suppression of fliG mutations. Interestingly, these cheY mutations dominantly suppressed both fliG and fliM mutations; this is consistent with the idea that the CheY protein interacts with both switch gene products during signaling. Biochemical characterization of wild-type and suppressor CheY proteins did not reveal altered phosphorylation properties or evidence for phosphorylation-dependent CheY multimerization. These data indicate that suppressor CheY proteins are specifically altered in the ability to transduce chemotactic signals to the switch at some point subsequent to phosphorylation. Physical mapping of suppressor amino acid substitutions on the crystal structure of CheY revealed a high degree of spatial clustering, suggesting that this region of CheY is a signaling surface that transduces chemotactic signals to the switch. Images PMID:1400175

THE TRUE IDENTITY OF COPELAND'S AQUATIC SCUTTLE FLY (DIPTERA: PHORIDAE) FROM INDIANA AND RECOGNITION OF A SIBLING SPECIES FROM TEXAS.

PubMed

Disney, R Henry L; Copeland, Robert S; Murrell, Ebony

2009-07-01

Among the insects reported by Copeland (1989) breeding in the waters retained by treeholes in Indiana was a scuttle fly identified by W. H. Robinson as Megaselia scalaris (Loew). It is here reported that in fact this fly, along with fresh material from Illinois and Missouri, is M. imitatrix Borgmeier, whose type series was from Puerto Rico. An aquatic species reported from Texas is recognized as a sibling species of M. imitatrix and is named M. hansonix Disney, sp. nov. A single female from Brazil represents a third species of this complex, thus raising doubts about the identity of specimens from Brazil attributed to M. imitatrix by Benton and Claugher (2000).

THE TRUE IDENTITY OF COPELAND'S AQUATIC SCUTTLE FLY (DIPTERA: PHORIDAE) FROM INDIANA AND RECOGNITION OF A SIBLING SPECIES FROM TEXAS

PubMed Central

Disney, R. Henry L.; Copeland, Robert S.; Murrell, Ebony

2012-01-01

Among the insects reported by Copeland (1989) breeding in the waters retained by treeholes in Indiana was a scuttle fly identified by W. H. Robinson as Megaselia scalaris (Loew). It is here reported that in fact this fly, along with fresh material from Illinois and Missouri, is M. imitatrix Borgmeier, whose type series was from Puerto Rico. An aquatic species reported from Texas is recognized as a sibling species of M. imitatrix and is named M. hansonix Disney, sp. nov. A single female from Brazil represents a third species of this complex, thus raising doubts about the identity of specimens from Brazil attributed to M. imitatrix by Benton and Claugher (2000). PMID:22879679

The Visual Orientation Memory of "Drosophila" Requires Foraging (PKG) Upstream of Ignorant (RSK2) in Ring Neurons of the Central Complex

ERIC Educational Resources Information Center

Kuntz, Sara; Poeck, Burkhard; Sokolowski, Marla B.; Strauss, Roland

2012-01-01

Orientation and navigation in a complex environment requires path planning and recall to exert goal-driven behavior. Walking "Drosophila" flies possess a visual orientation memory for attractive targets which is localized in the central complex of the adult brain. Here we show that this type of working memory requires the cGMP-dependent protein…

Ecological parameters of the (S)-9-methylgermacrene-B population of the Lutzomyia longipalpis complex in a visceral leishmaniasis area in São Paulo state, Brazil.

PubMed

Galvis-Ovallos, Fredy; Casanova, Claudio; Sevá, Anaiá da Paixão; Galati, Eunice Aparecida Bianchi

2017-05-30

Visceral leishmaniasis (VL) is an important public health challenge in Brazil because of the high number of human and canine cases reported annually. Leishmania infantum is the etiological agent of VL and Lutzomyia longipalpis is its main vector. However, evidence suggests that this taxon constitutes a species complex. In Sao Paulo state, there are two populations of Lu. longipalpis, each secreting distinct pheromones, (S)-9-methylgermacrene-B and Cembrene 1; both have been associated with different patterns of VL transmission. The aim of the present study was to investigate the temporal distribution and natural infection of the (S)-9-methylgermacrene-B population of the Lu. longipalpis complex in a highly VL endemic area of Sao Paulo state to obtain information that may contribute to the surveillance of this zoonosis and to the planning of preventive and control measures. The study was carried out in Panorama municipality, Sao Paulo State. Captures were made during 24 months in seven domiciles. The relation between sand fly abundance and climatic variables, temperature and humidity, was analyzed and natural infection by Leishmania spp. in sand fly females was investigated by nested PCR. A total of 4120 sand flies, with predominance of Lu. longipalpis (97.2%) were captured. The highest averages of sand flies/night/trap occurred in the rainy season (November-March) and a positive, significant correlation between sand fly abundance and the temperature and humidity 20 days before the capture days was found. Leishmania infantum DNA was detected in three out of 250 pools of females analyzed, giving an estimated minimum infection rate of 1.2%. The identification of the climatic association between the high abundance of the vector in this highly endemic VL focus constitutes a fundamental point for evaluating future vector and dog control measures and this information increases the data of VL foci in Sao Paulo state that could contribute to the public health authorities in planning prevention and control measures. The identification of natural infection by Le. infantum in Lu. longipalpis specimens reinforces the importance of entomological surveillance activities in this municipality.

Flying Cars

NASA Technical Reports Server (NTRS)

Crow, Steven

1996-01-01

Flying cars have nearly mythical appeal to nonpilots, a group that includes almost the whole human race. The appeal resides in the perceived utility of flying cars, vehicles that offer portal-to-portal transportation, yet break the bonds of road and traffic and travel freely through the sky at the drivers will. Part of the appeal is an assumption that flying cars can be as easy to fly as to drive. Flying cars have been part of the dream of aviation since the dawn of powered flight. Glenn Curtiss built, displayed, and maybe even flew a flying car in 1917, the Curtiss Autoplane. Many roadable airplanes were built in the 1930's, like the Waterman Arrowbile and the Fulton Airphibian. Two flying cars came close to production in the early 1950's. Ted Hall built a series of flying cars culminating in the Convaircar, sponsored by Consolidated Vultee, General Motors, and Hertz. Molt Taylor built and certified his Aerocar, and Ford came close to producing them. Three Aerocars are still flyable, two in museums in Seattle and Oshkosh, and the third owned and flown by Ed Sweeny. Flying cars do have problems, which so far have prevented commercial success. An obvious problem is complexity of the vehicle, the infrastructure, or both. Another is the difficulty of matching low power for normal driving with high power in flight. An automobile uses only about 20 hp at traffic speeds, while a personal airplane needs about 160 hp at speeds typical of flight. Many automobile engines can deliver 160 hp, but not for very long. A more subtle issue involves the drag of automobiles and airplanes. A good personal airplane can fly 30 miles per gallon of fuel at 200 mph. A good sports car would need 660 hp at the same speed and would travel only 3 miles per gallon. The difference is drag area, about 4.5 sq ft for the automobile and 1.4 sq ft for the airplane. A flying car better have the drag area of the airplane, not the car!

Brainstem Regions Involved in the Expiration Reflex. A c-fos Study in Anesthetized Cats

PubMed Central

Poliacek, Ivan; Halasova, Erika; Jakus, Jan; Murin, Peter; Barani, Helena; Stransky, Albert; Bolser, Donald C

2009-01-01

Expression of the immediate-early gene c-fos, a marker of neuronal activation, was employed to localize brainstem neuronal populations functionally related to the expiration reflex (ER). Twelve spontaneously breathing, non-decerebrate, pentobarbital anesthetized cats were used. The level of Fos-like immunoreactivity (FLI) in 6 animals with repetitive ERs mechanically induced from the glottis (296±9 ERs) was compared to FLI in 6 control non-stimulated cats. Respiratory rate, arterial blood pressure, and end tidal CO2 concentration remained stable during the experiment. In the medulla, increased FLI was found in the region of nucleus tractus solitarii (p<0.001), in the ventrolateral medulla along with the lateral tegmental field (p<0.01), and in the vestibular nuclei (p<0.01). In the pons, increased FLI was detected in the caudal extensions of the lateral parabrachial and Kölliker-Fuse nuclei (p<0.05). Within the rostral mesencephalon FLI was enhanced in the midline area (p<0.05). A lower level of ER-related FLI compared to control animals was detected in the pontine raphe region (p<0.05) and the lateral division of mesencephalic periaqueductal gray (p<0.05). The results suggest that the ER is coordinated by a complex long loop of medullary-pontine-mesencephalic neuronal circuits, some of which may differ from those of other respiratory reflexes. The FLI related to the expulsive behavior ER differs from that induced by laryngeal stimulation and laryngeal adductor responses, particularly in ventrolateral medulla and mesencephalon. PMID:17964550

Expression of the yeast NADH dehydrogenase Ndi1 in Drosophila confers increased lifespan independently of dietary restriction

PubMed Central

Sanz, Alberto; Soikkeli, Mikko; Portero-Otín, Manuel; Wilson, Angela; Kemppainen, Esko; McIlroy, George; Ellilä, Simo; Kemppainen, Kia K.; Tuomela, Tea; Lakanmaa, Matti; Kiviranta, Essi; Stefanatos, Rhoda; Dufour, Eric; Hutz, Bettina; Naudí, Alba; Jové, Mariona; Zeb, Akbar; Vartiainen, Suvi; Matsuno-Yagi, Akemi; Yagi, Takao; Rustin, Pierre; Pamplona, Reinald; Jacobs, Howard T.

2010-01-01

Mutations in mitochondrial oxidative phosphorylation complex I are associated with multiple pathologies, and complex I has been proposed as a crucial regulator of animal longevity. In yeast, the single-subunit NADH dehydrogenase Ndi1 serves as a non-proton-translocating alternative enzyme that replaces complex I, bringing about the reoxidation of intramitochondrial NADH. We have created transgenic strains of Drosophila that express yeast NDI1 ubiquitously. Mitochondrial extracts from NDI1-expressing flies displayed a rotenone-insensitive NADH dehydrogenase activity, and functionality of the enzyme in vivo was confirmed by the rescue of lethality resulting from RNAi knockdown of complex I. NDI1 expression increased median, mean, and maximum lifespan independently of dietary restriction, and with no change in sirtuin activity. NDI1 expression mitigated the aging associated decline in respiratory capacity and the accompanying increase in mitochondrial reactive oxygen species production, and resulted in decreased accumulation of markers of oxidative damage in aged flies. Our results support a central role of mitochondrial oxidative phosphorylation complex I in influencing longevity via oxidative stress, independently of pathways connected to nutrition and growth signaling. PMID:20435911

Noncoding RNAs of the Ultrabithorax Domain of the Drosophila Bithorax Complex

PubMed Central

Pease, Benjamin; Borges, Ana C.; Bender, Welcome

2013-01-01

RNA transcripts without obvious coding potential are widespread in many creatures, including the fruit fly, Drosophila melanogaster. Several noncoding RNAs have been identified within the Drosophila bithorax complex. These first appear in blastoderm stage embryos, and their expression patterns indicate that they are transcribed only from active domains of the bithorax complex. It has been suggested that these noncoding RNAs have a role in establishing active domains, perhaps by setting the state of Polycomb Response Elements A comprehensive survey across the proximal half of the bithorax complex has now revealed nine distinct noncoding RNA transcripts, including four within the Ultrabithorax transcription unit. At the blastoderm stage, the noncoding transcripts collectively span ∼75% of the 135 kb surveyed. Recombination-mediated cassette exchange was used to invert the promoter of one of the noncoding RNAs, a 23-kb transcript from the bxd domain of the bithorax complex. The resulting animals fail to make the normal bxd noncoding RNA and show no transcription across the bxd Polycomb Response Element in early embryos. The mutant flies look normal; the regulation of the bxd domain appears unaffected. Thus, the bxd noncoding RNA has no apparent function. PMID:24077301

ED13-0225-023

NASA Image and Video Library

2013-07-10

Scientists and technicians ready an instrument rack for mounting in NASA's DC-8 flying laboratory in preparation for a complex mission to study how air pollution and natural emissions affect climate change

OnTheFly: a database of Drosophila melanogaster transcription factors and their binding sites.

PubMed

Shazman, Shula; Lee, Hunjoong; Socol, Yakov; Mann, Richard S; Honig, Barry

2014-01-01

We present OnTheFly (http://bhapp.c2b2.columbia.edu/OnTheFly/index.php), a database comprising a systematic collection of transcription factors (TFs) of Drosophila melanogaster and their DNA-binding sites. TFs predicted in the Drosophila melanogaster genome are annotated and classified and their structures, obtained via experiment or homology models, are provided. All known preferred TF DNA-binding sites obtained from the B1H, DNase I and SELEX methodologies are presented. DNA shape parameters predicted for these sites are obtained from a high throughput server or from crystal structures of protein-DNA complexes where available. An important feature of the database is that all DNA-binding domains and their binding sites are fully annotated in a eukaryote using structural criteria and evolutionary homology. OnTheFly thus provides a comprehensive view of TFs and their binding sites that will be a valuable resource for deciphering non-coding regulatory DNA.

Quantification of gait parameters in freely walking wild type and sensory deprived Drosophila melanogaster

PubMed Central

Mendes, César S; Bartos, Imre; Akay, Turgay; Márka, Szabolcs; Mann, Richard S

2013-01-01

Coordinated walking in vertebrates and multi-legged invertebrates such as Drosophila melanogaster requires a complex neural network coupled to sensory feedback. An understanding of this network will benefit from systems such as Drosophila that have the ability to genetically manipulate neural activities. However, the fly's small size makes it challenging to analyze walking in this system. In order to overcome this limitation, we developed an optical method coupled with high-speed imaging that allows the tracking and quantification of gait parameters in freely walking flies with high temporal and spatial resolution. Using this method, we present a comprehensive description of many locomotion parameters, such as gait, tarsal positioning, and intersegmental and left-right coordination for wild type fruit flies. Surprisingly, we find that inactivation of sensory neurons in the fly's legs, to block proprioceptive feedback, led to deficient step precision, but interleg coordination and the ability to execute a tripod gait were unaffected. DOI: http://dx.doi.org/10.7554/eLife.00231.001 PMID:23326642

Methyl-orange and cadmium simultaneous removal using fly ash and photo-Fenton systems.

PubMed

Visa, Maria; Duta, Anca

2013-01-15

Wastewaters resulting from the textile and dye finishing industries need complex treatment for efficient removal of colour and other compounds existent in the dyeing and rising baths (heavy metals, surfactants, equalizers, etc.). Modified fly ash (FA) mixed with TiO(2) photocatalyst represent a viable option for simultaneous removal of dyes and heavy metals, and the optimized conditions are discussed in this paper for synthetic wastewaters containing methyl-orange (MO) and cadmium. For a cost-effective dye removal process, further tests were done, replacing the photocatalyst with a (photo)Fenton system. The optimized technological parameters (contact time, amount of fly ash and amount of Fe(2+)/H(2)O(2)) allow to reach removal efficiencies up to 88% for the heavy metal and up to 70% for the dye. The adsorption mechanisms and the process kinetic are discussed, also considering the possibility of in situ generation of the Fenton system, due to the fly ash composition. Copyright © 2012 Elsevier B.V. All rights reserved.

Effects of an African weaver ant, Oecophylla longinoda, in controlling mango fruit flies (Diptera: Tephritidae) in Benin.

PubMed

Van Mele, Paul; Vayssières, Jean-François; Van Tellingen, Esther; Vrolijks, Jan

2007-06-01

Six mango, Mangifera indica L., plantations around Parakou, northern Benin, were sampled at 2-wk intervals for fruit fly damage from early April to late May in 2005. Mean damage ranged from 1 to 24% with a weaver ant, Oecophylla longinoda (Latreille), being either abundant or absent. The fruit fly complex is made up of Ceratitis spp. and Bactrocera invadens Drew et al., a new invasive species in West Africa. In 2006, Ceratitis spp. peaked twice in the late dry season in early April and early May, whereas B. invadens populations quickly increased at the onset of the rains, from mid-May onward. Exclusion experiments conducted in 2006 with 'Eldon', 'Kent', and 'Gouverneur' confirmed that at high ant abundance levels, Oecophylla significantly reduced fruit fly infestation. Although fruit fly control methods are still at an experimental stage in this part of the world, farmers who tolerated weaver ants in their orchard were rewarded by significantly better fruit quality. Conservation biological control with predatory ants such as Oecophylla in high-value tree crops has great potential for African and Asian farmers. Implications for international research for development at the Consultative Group on International Agricultural Research level are discussed.

A Computational Method to Quantify Fly Circadian Activity.

PubMed

Lazopulo, Andrey; Syed, Sheyum

2017-10-28

In most animals and plants, circadian clocks orchestrate behavioral and molecular processes and synchronize them to the daily light-dark cycle. Fundamental mechanisms that underlie this temporal control are widely studied using the fruit fly Drosophila melanogaster as a model organism. In flies, the clock is typically studied by analyzing multiday locomotor recording. Such a recording shows a complex bimodal pattern with two peaks of activity: a morning peak that happens around dawn, and an evening peak that happens around dusk. These two peaks together form a waveform that is very different from sinusoidal oscillations observed in clock genes, suggesting that mechanisms in addition to the clock have profound effects in producing the observed patterns in behavioral data. Here we provide instructions on using a recently developed computational method that mathematically describes temporal patterns in fly activity. The method fits activity data with a model waveform that consists of four exponential terms and nine independent parameters that fully describe the shape and size of the morning and evening peaks of activity. The extracted parameters can help elucidate the kinetic mechanisms of substrates that underlie the commonly observed bimodal activity patterns in fly locomotor rhythms.

Flies lacking all synapsins are unexpectedly healthy but are impaired in complex behaviour.

PubMed

Godenschwege, Tanja A; Reisch, Dietmar; Diegelmann, Sören; Eberle, Kai; Funk, Natalja; Heisenberg, Martin; Hoppe, Viviane; Hoppe, Jürgen; Klagges, Bert R E; Martin, Jean-René; Nikitina, Ekaterina A; Putz, Gabi; Reifegerste, Rita; Reisch, Natascha; Rister, Jens; Schaupp, Michael; Scholz, Henrike; Schwärzel, Martin; Werner, Ursula; Zars, Troy D; Buchner, Sigrid; Buchner, Erich

2004-08-01

Vertebrate synapsins are abundant synaptic vesicle phosphoproteins that have been proposed to fine-regulate neurotransmitter release by phosphorylation-dependent control of synaptic vesicle motility. However, the consequences of a total lack of all synapsin isoforms due to a knock-out of all three mouse synapsin genes have not yet been investigated. In Drosophila a single synapsin gene encodes several isoforms and is expressed in most synaptic terminals. Thus the targeted deletion of the synapsin gene of Drosophila eliminates the possibility of functional knock-out complementation by other isoforms. Unexpectedly, synapsin null mutant flies show no obvious defects in brain morphology, and no striking qualitative changes in behaviour are observed. Ultrastructural analysis of an identified 'model' synapse of the larval nerve muscle preparation revealed no difference between wild-type and mutant, and spontaneous or evoked excitatory junction potentials at this synapse were normal up to a stimulus frequency of 5 Hz. However, when several behavioural responses were analysed quantitatively, specific differences between mutant and wild-type flies are noted. Adult locomotor activity, optomotor responses at high pattern velocities, wing beat frequency, and visual pattern preference are modified. Synapsin mutant flies show faster habituation of an olfactory jump response, enhanced ethanol tolerance, and significant defects in learning and memory as measured using three different paradigms. Larval behavioural defects are described in a separate paper. We conclude that Drosophila synapsins play a significant role in nervous system function, which is subtle at the cellular level but manifests itself in complex behaviour.

Enriching early adult environment affects the copulation behaviour of a tephritid fly.

PubMed

Díaz-Fleischer, Francisco; Arredondo, José; Aluja, Martín

2009-07-01

Early adult experiences in enriched environments favours animal brain and behavioural development ultimately resulting in an increased fitness. However, measuring the effect of environmental enrichment in animal behaviour in nature is often a complicated task, considering the complexity of the natural environment. We expanded previous studies to evaluate how early experience in an enriched environment affects copulation behaviour when animals are confronted with a complex semi-natural environment. Anastrepha ludens flies are an ideal model system for studying these effects because their natural habitats differ significantly from the cage environments in which these flies are reared for biological control purposes. For example, in the field, males form leks of up to six individuals. Each male defends a territory represented by a tree leaf whereas in rearing cages, territories are completely reduced because of the high population density. In a series of three experiments, we observed that male density represented the most influential stimulus for A. ludens male copulation success. Males that experienced lower densities in early adulthood obtained the highest proportion of copulations. By contrast, female copulation behaviour was not altered by female density. However, exposure to natural or artificial leaves in cages in which flies were kept until tested influenced female copulation behaviour. Females that were exposed to enriched environments exhibited a shorter latency to mate and shorter copulation durations with males than females reared in poor environments. We discuss the influence of early experience on male copulation success and female-mating choosiness.

Bat flies (Diptera: Nycteribiidae and Streblidae) infesting cave-dwelling bats in Gabon: diversity, dynamics and potential role in Polychromophilus melanipherus transmission.

PubMed

Obame-Nkoghe, Judicaël; Rahola, Nil; Bourgarel, Mathieu; Yangari, Patrick; Prugnolle, Franck; Maganga, Gael Darren; Leroy, Eric-Maurice; Fontenille, Didier; Ayala, Diego; Paupy, Christophe

2016-06-10

Evidence of haemosporidian infections in bats and bat flies has motivated a growing interest in characterizing their transmission cycles. In Gabon (Central Africa), many caves house massive colonies of bats that are known hosts of Polychromophilus Dionisi parasites, presumably transmitted by blood-sucking bat flies. However, the role of bat flies in bat malaria transmission remains under-documented. An entomological survey was carried out in four caves in Gabon to investigate bat fly diversity, infestation rates and host preferences and to determine their role in Polychromophilus parasite transmission. Bat flies were sampled for 2-4 consecutive nights each month from February to April 2011 (Faucon and Zadie caves) and from May 2012 to April 2013 (Kessipoughou and Djibilong caves). Bat flies isolated from the fur of each captured bat were morphologically identified and screened for infection by haemosporidian parasites using primers targeting the mitochondrial cytochrome b gene. Among the 1,154 bats captured and identified as Miniopterus inflatus Thomas (n = 354), Hipposideros caffer Sundevall complex (n = 285), Hipposideros gigas Wagner (n = 317), Rousettus aegyptiacus Geoffroy (n = 157, and Coleura afra Peters (n = 41), 439 (38.0 %) were infested by bat flies. The 1,063 bat flies recovered from bats belonged to five taxa: Nycteribia schmidlii scotti Falcoz, Eucampsipoda africana Theodor, Penicillidia fulvida Bigot, Brachytarsina allaudi Falcoz and Raymondia huberi Frauenfeld group. The mean infestation rate varied significantly according to the bat species (ANOVA, F (4,75) = 13.15, P < 0.001) and a strong association effect between bat fly species and host bat species was observed. Polychromophilus melanipherus Dionisi was mainly detected in N. s. scotti and P. fulvida and less frequently in E. africana, R. huberi group and B. allaudi bat flies. These results suggest that N. s. scotti and P. fulvida could potentially be involved in P. melanipherus transmission among cave-dwelling bats. Sequence analysis revealed eight haplotypes of P. melanipherus. This work represents the first documented record of the cave-dwelling bat fly fauna in Gabon and significantly contributes to our understanding of bat fly host-feeding behavior and their respective roles in Polychromophilus transmission.

Measuring Pilot Workload in a Moving-base Simulator. Part 2: Building Levels of Workload

NASA Technical Reports Server (NTRS)

Kantowitz, B. H.; Hart, S. G.; Bortolussi, M. R.; Shively, R. J.; Kantowitz, S. C.

1984-01-01

Pilot behavior in flight simulators often use a secondary task as an index of workload. His routine to regard flying as the primary task and some less complex task as the secondary task. While this assumption is quite reasonable for most secondary tasks used to study mental workload in aircraft, the treatment of flying a simulator through some carefully crafted flight scenario as a unitary task is less justified. The present research acknowledges that total mental workload depends upon the specific nature of the sub-tasks that a pilot must complete as a first approximation, flight tasks were divided into three levels of complexity. The simplest level (called the Base Level) requires elementary maneuvers that do not utilize all the degrees of freedom of which an aircraft, or a moving-base simulator; is capable. The second level (called the Paired Level) requires the pilot to simultaneously execute two Base Level tasks. The third level (called the Complex Level) imposes three simultaneous constraints upon the pilot.

Simple Algorithms for Distributed Leader Election in Anonymous Synchronous Rings and Complete Networks Inspired by Neural Development in Fruit Flies.

PubMed

Xu, Lei; Jeavons, Peter

2015-11-01

Leader election in anonymous rings and complete networks is a very practical problem in distributed computing. Previous algorithms for this problem are generally designed for a classical message passing model where complex messages are exchanged. However, the need to send and receive complex messages makes such algorithms less practical for some real applications. We present some simple synchronous algorithms for distributed leader election in anonymous rings and complete networks that are inspired by the development of the neural system of the fruit fly. Our leader election algorithms all assume that only one-bit messages are broadcast by nodes in the network and processors are only able to distinguish between silence and the arrival of one or more messages. These restrictions allow implementations to use a simpler message-passing architecture. Even with these harsh restrictions our algorithms are shown to achieve good time and message complexity both analytically and experimentally.

Simulating complex atomistic processes: On-the-fly kinetic Monte Carlo scheme with selective active volumes

NASA Astrophysics Data System (ADS)

Xu, Haixuan; Osetsky, Yury N.; Stoller, Roger E.

2011-10-01

An accelerated atomistic kinetic Monte Carlo (KMC) approach for evolving complex atomistic structures has been developed. The method incorporates on-the-fly calculations of transition states (TSs) with a scheme for defining active volumes (AVs) in an off-lattice (relaxed) system. In contrast to conventional KMC models that require all reactions to be predetermined, this approach is self-evolving and any physically relevant motion or reaction may occur. Application of this self-evolving atomistic kinetic Monte Carlo (SEAK-MC) approach is illustrated by predicting the evolution of a complex defect configuration obtained in a molecular dynamics (MD) simulation of a displacement cascade in Fe. Over much longer times, it was shown that interstitial clusters interacting with other defects may change their structure, e.g., from glissile to sessile configuration. The direct comparison with MD modeling confirms the atomistic fidelity of the approach, while the longer time simulation demonstrates the unique capability of the model.

Optic flow-based collision-free strategies: From insects to robots.

PubMed

Serres, Julien R; Ruffier, Franck

2017-09-01

Flying insects are able to fly smartly in an unpredictable environment. It has been found that flying insects have smart neurons inside their tiny brains that are sensitive to visual motion also called optic flow. Consequently, flying insects rely mainly on visual motion during their flight maneuvers such as: takeoff or landing, terrain following, tunnel crossing, lateral and frontal obstacle avoidance, and adjusting flight speed in a cluttered environment. Optic flow can be defined as the vector field of the apparent motion of objects, surfaces, and edges in a visual scene generated by the relative motion between an observer (an eye or a camera) and the scene. Translational optic flow is particularly interesting for short-range navigation because it depends on the ratio between (i) the relative linear speed of the visual scene with respect to the observer and (ii) the distance of the observer from obstacles in the surrounding environment without any direct measurement of either speed or distance. In flying insects, roll stabilization reflex and yaw saccades attenuate any rotation at the eye level in roll and yaw respectively (i.e. to cancel any rotational optic flow) in order to ensure pure translational optic flow between two successive saccades. Our survey focuses on feedback-loops which use the translational optic flow that insects employ for collision-free navigation. Optic flow is likely, over the next decade to be one of the most important visual cues that can explain flying insects' behaviors for short-range navigation maneuvers in complex tunnels. Conversely, the biorobotic approach can therefore help to develop innovative flight control systems for flying robots with the aim of mimicking flying insects' abilities and better understanding their flight. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

DNA Barcoding of Neotropical Sand Flies (Diptera, Psychodidae, Phlebotominae): Species Identification and Discovery within Brazil

PubMed Central

Pinto, Israel de Souza; Chagas, Bruna Dias das; Rodrigues, Andressa Alencastre Fuzari; Ferreira, Adelson Luiz; Rezende, Helder Ricas; Bruno, Rafaela Vieira; Falqueto, Aloisio; Andrade-Filho, José Dilermando; Galati, Eunice Aparecida Bianchi; Shimabukuro, Paloma Helena Fernandes; Brazil, Reginaldo Peçanha

2015-01-01

DNA barcoding has been an effective tool for species identification in several animal groups. Here, we used DNA barcoding to discriminate between 47 morphologically distinct species of Brazilian sand flies. DNA barcodes correctly identified approximately 90% of the sampled taxa (42 morphologically distinct species) using clustering based on neighbor-joining distance, of which four species showed comparatively higher maximum values of divergence (range 4.23–19.04%), indicating cryptic diversity. The DNA barcodes also corroborated the resurrection of two species within the shannoni complex and provided an efficient tool to differentiate between morphologically indistinguishable females of closely related species. Taken together, our results validate the effectiveness of DNA barcoding for species identification and the discovery of cryptic diversity in sand flies from Brazil. PMID:26506007

DNA Barcoding of Neotropical Sand Flies (Diptera, Psychodidae, Phlebotominae): Species Identification and Discovery within Brazil.

PubMed

Pinto, Israel de Souza; Chagas, Bruna Dias das; Rodrigues, Andressa Alencastre Fuzari; Ferreira, Adelson Luiz; Rezende, Helder Ricas; Bruno, Rafaela Vieira; Falqueto, Aloisio; Andrade-Filho, José Dilermando; Galati, Eunice Aparecida Bianchi; Shimabukuro, Paloma Helena Fernandes; Brazil, Reginaldo Peçanha; Peixoto, Alexandre Afranio

2015-01-01

DNA barcoding has been an effective tool for species identification in several animal groups. Here, we used DNA barcoding to discriminate between 47 morphologically distinct species of Brazilian sand flies. DNA barcodes correctly identified approximately 90% of the sampled taxa (42 morphologically distinct species) using clustering based on neighbor-joining distance, of which four species showed comparatively higher maximum values of divergence (range 4.23-19.04%), indicating cryptic diversity. The DNA barcodes also corroborated the resurrection of two species within the shannoni complex and provided an efficient tool to differentiate between morphologically indistinguishable females of closely related species. Taken together, our results validate the effectiveness of DNA barcoding for species identification and the discovery of cryptic diversity in sand flies from Brazil.

Insects as vectors: systematics and biology.

PubMed

Rodhain, F

2015-04-01

Among the many complex relationships between insects and microorganisms such as viruses, bacteria and parasites, some have resulted in the establishment of biological systems within which the insects act as a biological vector for infectious agents. It is therefore advisable to understand the identity and biology of these vectors in depth, in order to define procedures for epidemiological surveillance and anti-vector control. The following are successively reviewed in this article: Anoplura (lice), Siphonaptera (fleas), Heteroptera (bugs: Cimicidae, Triatoma, Belostomatidae), Psychodidae (sandflies), Simuliidae (black flies), Ceratopogonidae (biting midges), Culicidae (mosquitoes), Tabanidae (horseflies) and Muscidae (tsetse flies, stable flies and pupipara). The authors provide a rapid overview of the morphology, systematics, development cycle and bio-ecology of each of these groups of vectors. Finally, their medical and veterinary importance is briefly reviewed.

I Believe I Can Fly!: Use of Drosophila as a Model Organism in Neuropsychopharmacology Research.

PubMed

Narayanan, Anjana S; Rothenfluh, Adrian

2016-05-01

Neuropsychiatric disorders are of complex etiology, often including a large genetic component. In order to help identify and study the molecular and physiological mechanisms that such genes participate in, numerous animal models have been established in a variety of species. Over the past decade, this has increasingly included the vinegar fly, Drosophila melanogaster. Here, we outline why we study an invertebrate organism in the context of neuropsychiatric disorders, and we discuss how we can gain insight from studies in Drosophila. We focus on a few disorders and findings to make the larger point that modeling these diseases in flies can have both mechanistic and predictive validity. Highlighting some translational examples, we underline the fact that their brains works more like ours than one would have anticipated.

The beetle Tribolium castaneum has a fushi tarazu homolog expressed in stripes during segmentation

NASA Technical Reports Server (NTRS)

Brown, S. J.; Hilgenfeld, R. B.; Denell, R. E.; Spooner, B. S. (Principal Investigator)

1994-01-01

The genetic control of embryonic organization is far better understood for the fruit fly Drosophila melanogaster than for any other metazoan. A gene hierarchy acts during oogenesis and embryogenesis to regulate the establishment of segmentation along the anterior-posterior axis, and homeotic selector genes define developmental commitments within each parasegmental unit delineated. One of the most intensively studied Drosophila segmentation genes is fushi tarazu (ftz), a pair-rule gene expressed in stripes that is important for the establishment of the parasegmental boundaries. Although ftz is flanked by homeotic selector genes conserved throughout the metazoa, there is no evidence that it was part of the ancestral homeotic complex, and it has been unclear when the gene arose and acquired a role in segmentation. We show here that the beetle Tribolium castaneum has a ftz homolog located in its Homeotic complex and expressed in a pair-rule fashion, albeit in a register differing from that of the fly gene. These and other observations demonstrate that a ftz gene preexisted the radiation of holometabolous insects and suggest that it has a role in beetle embryogenesis which differs somewhat from that described in flies.

A pair of dopamine neurons target the D1-like dopamine receptor DopR in the central complex to promote ethanol-stimulated locomotion in Drosophila.

PubMed

Kong, Eric C; Woo, Katherine; Li, Haiyan; Lebestky, Tim; Mayer, Nasima; Sniffen, Melissa R; Heberlein, Ulrike; Bainton, Roland J; Hirsh, Jay; Wolf, Fred W

2010-04-01

Dopamine is a mediator of the stimulant properties of drugs of abuse, including ethanol, in mammals and in the fruit fly Drosophila. The neural substrates for the stimulant actions of ethanol in flies are not known. We show that a subset of dopamine neurons and their targets, through the action of the D1-like dopamine receptor DopR, promote locomotor activation in response to acute ethanol exposure. A bilateral pair of dopaminergic neurons in the fly brain mediates the enhanced locomotor activity induced by ethanol exposure, and promotes locomotion when directly activated. These neurons project to the central complex ellipsoid body, a structure implicated in regulating motor behaviors. Ellipsoid body neurons are required for ethanol-induced locomotor activity and they express DopR. Elimination of DopR blunts the locomotor activating effects of ethanol, and this behavior can be restored by selective expression of DopR in the ellipsoid body. These data tie the activity of defined dopamine neurons to D1-like DopR-expressing neurons to form a neural circuit that governs acute responding to ethanol.

The analysis of a generic air-to-air missile simulation model

NASA Technical Reports Server (NTRS)

Kaplan, Joseph A.; Chappell, Alan R.; Mcmanus, John W.

1994-01-01

A generic missile model was developed to evaluate the benefits of using a dynamic missile fly-out simulation system versus a static missile launch envelope system for air-to-air combat simulation. This paper examines the performance of a launch envelope model and a missile fly-out model. The launch envelope model bases its probability of killing the target aircraft on the target aircraft's position at the launch time of the weapon. The benefits gained from a launch envelope model are the simplicity of implementation and the minimal computational overhead required. A missile fly-out model takes into account the physical characteristics of the missile as it simulates the guidance, propulsion, and movement of the missile. The missile's probability of kill is based on the missile miss distance (or the minimum distance between the missile and the target aircraft). The problems associated with this method of modeling are a larger computational overhead, the additional complexity required to determine the missile miss distance, and the additional complexity of determining the reason(s) the missile missed the target. This paper evaluates the two methods and compares the results of running each method on a comprehensive set of test conditions.

Metagenomic analysis reveals a functional signature for biomass degradation by cecal microbiota in the leaf-eating flying squirrel (Petaurista alborufus lena)

PubMed Central

2012-01-01

Background Animals co-evolve with their gut microbiota; the latter can perform complex metabolic reactions that cannot be done independently by the host. Although the importance of gut microbiota has been well demonstrated, there is a paucity of research regarding its role in foliage-foraging mammals with a specialized digestive system. Results In this study, a 16S rRNA gene survey and metagenomic sequencing were used to characterize genetic diversity and functional capability of cecal microbiota of the folivorous flying squirrel (Petaurista alborufus lena). Phylogenetic compositions of the cecal microbiota derived from 3 flying squirrels were dominated by Firmicutes. Based on end-sequences of fosmid clones from 1 flying squirrel, we inferred that microbial metabolism greatly contributed to intestinal functions, including degradation of carbohydrates, metabolism of proteins, and synthesis of vitamins. Moreover, 33 polysaccharide-degrading enzymes and 2 large genomic fragments containing a series of carbohydrate-associated genes were identified. Conclusions Cecal microbiota of the leaf-eating flying squirrel have great metabolic potential for converting diverse plant materials into absorbable nutrients. The present study should serve as the basis for future investigations, using metagenomic approaches to elucidate the intricate mechanisms and interactions between host and gut microbiota of the flying squirrel digestive system, as well as other mammals with similar adaptations. PMID:22963241

Behavioral consequences of dopamine deficiency in the Drosophila central nervous system

PubMed Central

Riemensperger, Thomas; Isabel, Guillaume; Coulom, Hélène; Neuser, Kirsa; Seugnet, Laurent; Kume, Kazuhiko; Iché-Torres, Magali; Cassar, Marlène; Strauss, Roland; Preat, Thomas; Hirsh, Jay; Birman, Serge

2011-01-01

The neuromodulatory function of dopamine (DA) is an inherent feature of nervous systems of all animals. To learn more about the function of neural DA in Drosophila, we generated mutant flies that lack tyrosine hydroxylase, and thus DA biosynthesis, selectively in the nervous system. We found that DA is absent or below detection limits in the adult brain of these flies. Despite this, they have a lifespan similar to WT flies. These mutants show reduced activity, extended sleep time, locomotor deficits that increase with age, and they are hypophagic. Whereas odor and electrical shock avoidance are not affected, aversive olfactory learning is abolished. Instead, DA-deficient flies have an apparently “masochistic” tendency to prefer the shock-associated odor 2 h after conditioning. Similarly, sugar preference is absent, whereas sugar stimulation of foreleg taste neurons induces normal proboscis extension. Feeding the DA precursor l-DOPA to adults substantially rescues the learning deficit as well as other impaired behaviors that were tested. DA-deficient flies are also defective in positive phototaxis, without alteration in visual perception and optomotor response. Surprisingly, visual tracking is largely maintained, and these mutants still possess an efficient spatial orientation memory. Our findings show that flies can perform complex brain functions in the absence of neural DA, whereas specific behaviors involving, in particular, arousal and choice require normal levels of this neuromodulator. PMID:21187381

Single Event Testing on Complex Devices: Test Like You Fly versus Test-Specific Design Structures

NASA Technical Reports Server (NTRS)

Berg, Melanie; LaBel, Kenneth A.

2014-01-01

We present a framework for evaluating complex digital systems targeted for harsh radiation environments such as space. Focus is limited to analyzing the single event upset (SEU) susceptibility of designs implemented inside Field Programmable Gate Array (FPGA) devices. Tradeoffs are provided between application-specific versus test-specific test structures.

simSchool: The Game of Teaching

ERIC Educational Resources Information Center

Zibit, Melanie; Gibson, David

2005-01-01

"simSchool" is a classroom simulation program funded by the Preparing Tomorrow's Teachers to Teach with Technology (PT3) program of the U.S. Department of Education. Just as a flight-simulator immerses a player in the complexities of flying a plane, "simSchool" immerses novice teachers in some of the complexities of teaching 7th-12th grade…

KSC-2013-3605

NASA Image and Video Library

2013-09-18

CAPE CANAVERAL, Fla. -- An airship from the British Broadcasting Corp., or BBC, flies over Launch Complex 39 past the NASA News Center at NASA's Kennedy Space Center in Florida. A team of scientists from the BBC's television project "Cloud Lab" are conducting a number of experiments aboard the airship as it flies across the U.S., exploring all aspects of the Earth's atmosphere. One of the experiments is NASA's Microorganisms in the Stratosphere, or MIST, which is designed to measure the microbial survival and cellular responses to exposure in the upper atmosphere. Photo credit: NASA/Dimitri Gerondidakis

Restoration of fly ash dump through biological interventions.

PubMed

Juwarkar, Asha A; Jambhulkar, Hemlata P

2008-04-01

Field experiment on 10 ha area of fly ash dump was conducted to restore and revegetate it using biological interventions, which involves use of organic amendment, selection of suitable plant species along with specialized nitrogen fixing strains of biofertilizer. The results of the study indicated that amendment with farm yard manure at 50 t/ha improved the physical properties of fly ash such as maximum water holding capacity from 40.0 to 62.42% while porosity improved from 56.78 to 58.45%. The nitrogen content was increased by 4.5 times due to addition of nitrogen fixing strains of Bradyrhizobium and Azotobacter species, while phosphate content was increased by 10.0 times due to addition of VAM, which helps in phosphate immobilization. Due to biofertilizer inoculation different microbial groups such as Rhizobium, Azotobacter and VAM spores, which were practically absent in fly ash improved to 7.1 x 10(7), 9.2 x 10(7) CFU/g and 35 VAM spores/10 g of fly ash, respectively. Inoculation of biofertilizer and application of FYM helped in reducing the toxicity of heavy metals such as cadmium, copper, nickel and lead which were reduced by 25, 46, 48 and 47%, respectively, due to the increased organic matter content in the fly ash which complexes the heavy metals thereby decreasing the toxicity of metals. Amendment of fly ash with FYM and biofertilizer helped in profuse root development showing 15 times higher growth in Dendrocalamus strictus plant as compared to the control. Thus amendment and biofertilizer application provided better supportive material for anchorage and growth of the plant.

Climate change and the effects of temperature extremes on Australian flying-foxes.

PubMed

Welbergen, Justin A; Klose, Stefan M; Markus, Nicola; Eby, Peggy

2008-02-22

Little is known about the effects of temperature extremes on natural systems. This is of increasing concern now that climate models predict dramatic increases in the intensity, duration and frequency of such extremes. Here we examine the effects of temperature extremes on behaviour and demography of vulnerable wild flying-foxes (Pteropus spp.). On 12 January 2002 in New South Wales, Australia, temperatures exceeding 42 degrees C killed over 3500 individuals in nine mixed-species colonies. In one colony, we recorded a predictable sequence of thermoregulatory behaviours (wing-fanning, shade-seeking, panting and saliva-spreading, respectively) and witnessed how 5-6% of bats died from hyperthermia. Mortality was greater among the tropical black flying-fox, Pteropus alecto (10-13%) than the temperate grey-headed flying-fox, Pteropus poliocephalus (less than 1%), and young and adult females were more affected than adult males (young, 23-49%; females, 10-15%; males, less than 3%). Since 1994, over 30000 flying-foxes (including at least 24500 P. poliocephalus) were killed during 19 similar events. Although P. alecto was relatively less affected, it is currently expanding its range into the more variable temperature envelope of P. poliocephalus, which increases the likelihood of die-offs occurring in this species. Temperature extremes are important additional threats to Australian flying-foxes and the ecosystem services they provide, and we recommend close monitoring of colonies where temperatures exceeding 42.0 degrees C are predicted. The effects of temperature extremes on flying-foxes highlight the complex implications of climate change for behaviour, demography and species survival.

A tsetse and tabanid fly survey of African great apes habitats reveals the presence of a novel trypanosome lineage but the absence of Trypanosoma brucei.

PubMed

Votýpka, Jan; Rádrová, Jana; Skalický, Tomáš; Jirků, Milan; Jirsová, Dagmar; Mihalca, Andrei D; D'Amico, Gianluca; Petrželková, Klára J; Modrý, David; Lukeš, Julius

2015-10-01

Tsetse and tabanid flies transmit several Trypanosoma species, some of which are human and livestock pathogens of major medical and socioeconomic impact in Africa. Recent advances in molecular techniques and phylogenetic analyses have revealed a growing diversity of previously unidentified tsetse-transmitted trypanosomes potentially pathogenic to livestock and/or other domestic animals as well as wildlife, including African great apes. To map the distribution, prevalence and co-occurrence of known and novel trypanosome species, we analyzed tsetse and tabanid flies collected in the primary forested part of the Dzanga-Sangha Protected Areas, Central African Republic, which hosts a broad spectrum of wildlife including primates and is virtually devoid of domestic animals. Altogether, 564 tsetse flies and 81 tabanid flies were individually screened for the presence of trypanosomes using 18S rRNA-specific nested PCR. Herein, we demonstrate that wildlife animals are parasitized by a surprisingly wide range of trypanosome species that in some cases may circulate via these insect vectors. While one-third of the examined tsetse flies harbored trypanosomes either from the Trypanosoma theileri, Trypanosoma congolense or Trypanosoma simiae complex, or one of the three new members of the genus Trypanosoma (strains 'Bai', 'Ngbanda' and 'Didon'), more than half of the tabanid flies exclusively carried T. theileri. To establish the putative vertebrate hosts of the novel trypanosome species, we further analyzed the provenance of blood meals of tsetse flies. DNA individually isolated from 1033 specimens of Glossina spp. and subjected to high-throughput library-based screening proved that most of the examined tsetse flies engorged on wild ruminants (buffalo, sitatunga, bongo), humans and suids. Moreover, they also fed (albeit more rarely) on other vertebrates, thus providing indirect but convincing evidence that trypanosomes can be transmitted via these vectors among a wide range of warm- and cold-blooded hosts. Copyright © 2015 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Genetics Home Reference: Ewing sarcoma

MedlinePlus

... FLI-1, is associated with both TFIID and RNA polymerase II: interactions between two members of the ... EWS and hTAFII68, and subunits of TFIID and RNA polymerase II complexes. Mol Cell Biol. 1998 Mar; ...

Identifying behavioral circuits in Drosophila melanogaster: moving targets in a flying insect.

PubMed

Griffith, Leslie C

2012-08-01

Drosophila melanogaster has historically been the premier model system for understanding the molecular and genetic bases of complex behaviors. In the last decade technical advances, in the form of new genetic tools and electrophysiological and optical methods, have allowed investigators to begin to dissect the neuronal circuits that generate behavior in the adult. The blossoming of circuit analysis in this organism has also reinforced our appreciation of the inadequacy of wiring diagrams for specifying complex behavior. Neuromodulation and neuronal plasticity act to reconfigure circuits on both short and long time scales. These processes act on the connectome, providing context by integrating external and internal cues that are relevant for behavioral choices. New approaches in the fly are providing insight into these basic principles of circuit function. Copyright © 2012 Elsevier Ltd. All rights reserved.

Drosophila Ack targets its substrate, the sorting nexin DSH3PX1, to a protein complex involved in axonal guidance.

PubMed

Worby, Carolyn A; Simonson-Leff, Nancy; Clemens, James C; Huddler, Donald; Muda, Marco; Dixon, Jack E

2002-03-15

Dock, the Drosophila orthologue of Nck, is an adaptor protein that is known to function in axonal guidance paradigms in the fly including proper development of neuronal connections in photoreceptor cells and axonal tracking in Bolwig's organ. To develop a better understanding of axonal guidance at the molecular level, we purified proteins in a complex with the SH2 domain of Dock from fly Schneider 2 cells. A protein designated p145 was identified and shown to be a tyrosine kinase with sequence similarity to mammalian Cdc-42-associated tyrosine kinases. We demonstrate that Drosophila Ack (DAck) can be co-immunoprecipitated with Dock and DSH3PX1 from fly cell extracts. The domains responsible for the in vitro interaction between Drosophila Ack and Dock were identified, and direct protein-protein interactions between complex members were established. We conclude that DSH3PX1 is a substrate for DAck in vivo and in vitro and define one of the major in vitro sites of DSH3PX1 phosphorylation to be Tyr-56. Tyr-56 is located within the SH3 domain of DSH3PX1, placing it in an important position for regulating the binding of proline-rich targets. We demonstrate that Tyr-56 phosphorylation by DAck diminishes the DSH3PX1 SH3 domain interaction with the Wiskott-Aldrich Syndrome protein while enabling DSH3PX1 to associate with Dock. Furthermore, when Tyr-56 is mutated to aspartate or glutamate, the binding to Wiskott-Aldrich Syndrome protein is abrogated. These results suggest that the phosphorylation of DSH3PX1 by DAck targets this sorting nexin to a protein complex that includes Dock, an adaptor protein important for axonal guidance.

[Identification of potentially invasive species of black flies [Diptera: Simuliidae] from Armenia based on an analysis of variability in the mtDNA barcode of the cox1 gene and chromosomal polymorphism].

PubMed

Andrianov, B V; Goryacheva, I I; Vlasov, S V; Gorelova, T V; Harutyunova, M V; Harutyunova, K V; Mayilyan, K R; Zakharov, I A

2015-03-01

Black flies (Diptera, Simuliidae) are well known for their medical, environmental, and veterinary importance. The simuliid fauna of Armenia includes 53 species. A number of dominant species are of ecological importance. Complex analysis, which involved morphometric, cytogenetic, and molecular genetic approaches, was conducted to characterize the species status of black flies inhabiting the territory of Armenia. It was shown that the predominant simuliid species, Simulium paraequinum and Simulium kiritshenkoi, belong to a group of species with minimal variability of the cox1 gene. The recently discovered species, Simulium noellery and Simulium [B.] erythrocephalum, which are new to Armenia, can be considered as potentially invasive, which is supported by the low level of variability of the cox1 gene.

An artificial neural network controller based on MPSO-BFGS hybrid optimization for spherical flying robot

NASA Astrophysics Data System (ADS)

Liu, Xiaolin; Li, Lanfei; Sun, Hanxu

2017-12-01

Spherical flying robot can perform various tasks in the complex and varied environment to reduce labor costs. However, it is difficult to guarantee the stability of the spherical flying robot in the case of strong coupling and time-varying disturbance. In this paper, an artificial neural network controller (ANNC) based on MPSO-BFGS hybrid optimization algorithm is proposed. The MPSO algorithm is used to optimize the initial weights of the controller to avoid the local optimal solution. The BFGS algorithm is introduced to improve the convergence ability of the network. We use Lyapunov method to analyze the stability of ANNC. The controller is simulated under the condition of nonlinear coupling disturbance. The experimental results show that the proposed controller can obtain the expected value in shoter time compared with the other considered methods.

Biomass fly ash incorporation in cement based materials =

NASA Astrophysics Data System (ADS)

Rajamma, Rejini

In recent years, pressures on global environment and energy security have led to an increasing demand on renewable energy sources, and diversification of Europe's energy supply. Among these resources the biomass could exert an important role, since it is considered a renewable and CO2 neutral energy resource once the consumption rate is lower than the growth rate, and can potentially provide energy for heat, power and transports from the same installation. Currently, most of the biomass ash produced in industrial plants is either disposed of in landfill or recycled on agricultural fields or forest, and most times this goes on without any form of control. However, considering that the disposal cost of biomass ashes are raising, and that biomass ash volumes are increasing worldwide, a sustainable ash management has to be established. The main objective of the present study is the effect of biomass fly ashes in cement mortars and concretes in order to be used as a supplementary cementitious material. The wastes analyzed in the study were collected from the fluidized bed boilers and grate boilers available in the thermal power plants and paper pulp plants situated in Portugal. The physical as well as chemical characterisations of the biomass fly ashes were investigated. The cement was replaced by the biomass fly ashes in 10, 20 and 30% (weight %) in order to investigate the fresh properties as well as the hardened properties of biomass fly ash incorporated cement mortar and concrete formulations. Expansion reactions such as alkali silica reaction (ASR), sulphate attack (external and internal) were conducted in order to check the durability of the biomass fly ash incorporated cement mortars and concretes. Alternative applications such as incorporation in lime mortars and alkali activation of the biomass fly ashes were also attempted. The biomass fly ash particles were irregular in shape and fine in nature. The chemical characterization revealed that the biomass fly ashes were similar to a class C fly ash. The mortar results showed a good scope for biomass fly ashes as supplementary cementitious materials in lower dosages (<20%). The poor workability, concerns about the organic content, alkalis, chlorides and sulphates stand as the reasons for preventing the use of biomass fly ash in high content in the cement mortars. The results obtained from the durability tests have shown a clear reduction in expansion for the biomass fly ash mortars/concretes and the binder blend made with biomass fly ash (20%) and metakaolin (10%) inhibited the ASR reaction effectively. The biomass fly ash incorporation in lime mortars did not improve the mortar properties significantly though the carbonation was enhanced in the 15-20% incorporation. The biomass fly ash metakaolin blend worked well in the alkali activated complex binder application also. Portland cement free binders (with 30-40 MPa compressive strength) were obtained on the alkali activation of biomass fly ashes (60-80%) blended with metakaolin (20-40%).

Mortality from desiccation contributes to a genotype–temperature interaction for cold survival in Drosophila melanogaster

PubMed Central

Kobey, Robert L.; Montooth, Kristi L.

2013-01-01

SUMMARY Survival at cold temperatures is a complex trait, primarily because of the fact that the physiological cause of injury may differ across degrees of cold exposure experienced within the lifetime of an ectothermic individual. In order to better understand how chill-sensitive insects experience and adapt to low temperatures, we investigated the physiological basis for cold survival across a range of temperature exposures from −4 to 6°C in five genetic lines of the fruit fly Drosophila melanogaster. Genetic effects on cold survival were temperature dependent and resulted in a significant genotype–temperature interaction for survival across cold temperature exposures that differ by as little as 2°C. We investigated desiccation as a potential mechanism of injury across these temperature exposures. Flies were dehydrated following exposures near 6°C, whereas flies were not dehydrated following exposures near −4°C. Furthermore, decreasing humidity during cold exposure decreased survival, and increasing humidity during cold exposure increased survival at 6°C, but not at −4°C. These results support the conclusion that in D. melanogaster there are multiple physiological mechanisms of cold-induced mortality across relatively small differences in temperature, and that desiccation contributes to mortality for exposures near 6°C but not for subzero temperatures. Because D. melanogaster has recently expanded its range from tropical to temperate latitudes, the complex physiologies underlying cold tolerance are likely to be important traits in the recent evolutionary history of this fruit fly. PMID:23197100

Blocking synaptic transmission with tetanus toxin light chain reveals modes of neurotransmission in the PDF-positive circadian clock neurons of Drosophila melanogaster.

PubMed

Umezaki, Yujiro; Yasuyama, Kouji; Nakagoshi, Hideki; Tomioka, Kenji

2011-09-01

Circadian locomotor rhythms of Drosophila melanogaster are controlled by a neuronal circuit composed of approximately 150 clock neurons that are roughly classified into seven groups. In the circuit, a group of neurons expressing pigment-dispersing factor (PDF) play an important role in organizing the pacemaking system. Recent studies imply that unknown chemical neurotransmitter(s) (UNT) other than PDF is also expressed in the PDF-positive neurons. To explore its role in the circadian pacemaker, we examined the circadian locomotor rhythms of pdf-Gal4/UAS-TNT transgenic flies in which chemical synaptic transmission in PDF-positive neurons was blocked by expressed tetanus toxin light chain (TNT). In constant darkness (DD), the flies showed a free-running rhythm, which was similar to that of wild-type flies but significantly different from pdf null mutants. Under constant light conditions (LL), however, they often showed complex rhythms with a short period and a long period component. The UNT is thus likely involved in the synaptic transmission in the clock network and its release caused by LL leads to arrhythmicity. Immunocytochemistry revealed that LL induced phase separation in TIMELESS (TIM) cycling among some of the PDF-positive and PDF-negative clock neurons in the transgenic flies. These results suggest that both PDF and UNT play important roles in the Drosophila circadian clock, and activation of PDF pathway alone by LL leads to the complex locomotor rhythm through desynchronized oscillation among some of the clock neurons. Copyright © 2011 Elsevier Ltd. All rights reserved.

Command and Compensation in a Neuromodulatory Decision Network

PubMed Central

Luan, Haojiang; Diao, Fengqiu; Peabody, Nathan C.; White, Benjamin H.

2012-01-01

The neural circuits that mediate behavioral choices must not only weigh internal demands and environmental circumstances, but also select and implement specific actions, including associated visceral or neuroendocrine functions. Coordinating these multiple processes suggests considerable complexity. As a consequence, even circuits that support simple behavioral decisions remain poorly understood. Here we show that the environmentally-sensitive wing expansion decision of adult fruit flies is coordinated by a single pair of neuromodulatory neurons with command-like function. Targeted suppression of these neurons using the Split Gal4 system abrogates the fly's ability to expand its wings in the face of environmental challenges, while stimulating them forces expansion by coordinately activating both motor and neuroendocrine outputs. The arbitration and implementation of the wing expansion decision by this neuronal pair may illustrate a general strategy by which neuromodulatory neurons orchestrate behavior. Interestingly, the decision network shows a behavioral plasticity that is unmasked under conducive environmental conditions in flies lacking the function of the command-like neuromodulatory neurons. Such flies can often expand their wings using a motor program distinct from that of wildtype animals and controls. This compensatory program may be the vestige of an ancestral, environmentally-insensitive program used for wing expansion that existed prior to the evolution of the environmentally-adaptive program currently used by Drosophila and other cyclorrhaphan flies. PMID:22262886

Intelligent agents: adaptation of autonomous bimodal microsystems

NASA Astrophysics Data System (ADS)

Smith, Patrice; Terry, Theodore B.

2014-03-01

Autonomous bimodal microsystems exhibiting survivability behaviors and characteristics are able to adapt dynamically in any given environment. Equipped with a background blending exoskeleton it will have the capability to stealthily detect and observe a self-chosen viewing area while exercising some measurable form of selfpreservation by either flying or crawling away from a potential adversary. The robotic agent in this capacity activates a walk-fly algorithm, which uses a built in multi-sensor processing and navigation subsystem or algorithm for visual guidance and best walk-fly path trajectory to evade capture or annihilation. The research detailed in this paper describes the theoretical walk-fly algorithm, which broadens the scope of spatial and temporal learning, locomotion, and navigational performances based on optical flow signals necessary for flight dynamics and walking stabilities. By observing a fly's travel and avoidance behaviors; and, understanding the reverse bioengineering research efforts of others, we were able to conceptualize an algorithm, which works in conjunction with decisionmaking functions, sensory processing, and sensorimotor integration. Our findings suggest that this highly complex decentralized algorithm promotes inflight or terrain travel mobile stability which is highly suitable for nonaggressive micro platforms supporting search and rescue (SAR), and chemical and explosive detection (CED) purposes; a necessity in turbulent, non-violent structured or unstructured environments.

Blow flies as urban wildlife sensors.

PubMed

Hoffmann, Constanze; Merkel, Kevin; Sachse, Andreas; Rodríguez, Pablo; Leendertz, Fabian H; Calvignac-Spencer, Sébastien

2018-05-01

Wildlife detection in urban areas is very challenging. Conventional monitoring techniques such as direct observation are faced with the limitation that urban wildlife is extremely elusive. It was recently shown that invertebrate-derived DNA (iDNA) can be used to assess wildlife diversity in tropical rainforests. Flies, which are ubiquitous and very abundant in most cities, may also be used to detect wildlife in urban areas. In urban ecosystems, however, overwhelming quantities of domestic mammal DNA could completely mask the presence of wild mammal DNA. To test whether urban wild mammals can be detected using fly iDNA, we performed DNA metabarcoding of pools of flies captured in Berlin, Germany, using three combinations of blocking primers. Our results show that domestic animal sequences are, as expected, very dominant in urban environments. Nevertheless, wild mammal sequences can often be retrieved, although they usually only represent a minor fraction of the sequence reads. Fly iDNA metabarcoding is therefore a viable approach for quick scans of urban wildlife diversity. Interestingly, our study also shows that blocking primers can interact with each other in ways that affect the outcome of metabarcoding. We conclude that the use of complex combinations of blocking primers, although potentially powerful, should be carefully planned when designing experiments. © 2018 John Wiley & Sons Ltd.

Diversity of pollination ecology in the Schismatoglottis Calyptrata Complex Clade (Araceae).

PubMed

Hoe, Y C; Gibernau, M; Wong, S Y

2018-05-01

Field studies integrating pollination investigations with an assessment of floral scent composition and thermogenesis in tropical aroids are rather few. Thus, this study aimed to investigate the pollination biology of nine species belonging to Schismatoglottis Calyptrata Complex Clade. The flowering mechanism, visiting insect activities, reproductive system, thermogenesis and floral scent composition were examined. Anthesis for all species started at dawn and lasted 25-29 h. Colocasiomyia (Diptera, Drosophilidae) are considered the main pollinators for all the investigated species. Cycreon (Coleoptera, Hydrophilidae) are considered secondary pollinators as they are only present in seven of the nine host plants, despite the fact that they are the most effective pollen carrier, carrying up to 15 times more pollen grains than Colocasiomyia flies. However, the number of Colocasiomyia individuals was six times higher than Cycreon beetles. Chaloenus (Chrysomelidae, Galeuricinae) appeared to be an inadvertent pollinator. Atheta (Coleoptera, Staphylinidae) is considered a floral visitor in most investigated species of the Calyptrata Complex Clade in Sarawak, but a possible pollinator in S. muluensis. Chironomidae midges and pteromalid wasps are considered visitors in S. calyptrata. Thermogenesis in a biphasic pattern was observed in inflorescences of S. adducta, S. calyptrata, S. giamensis, S. pseudoniahensis and S. roh. The first peak occurred during pistillate anthesis; the second peak during staminate anthesis. Inflorescences of all investigated species of Calyptrata Complex Clade emitted four types of ester compound, with methyl ester-3-methyl-3-butenoic acid as a single major VOC (volatile organic compound). The appendix, pistillate zone, staminate zone and spathe emitted all these compounds. A mixed fly-beetle pollination system is considered an ancestral trait in the Calyptrata Complex Clade, persisting in Sarawak taxa, whereas the marked reduction of interpistillar staminodes in taxa from Peninsular Malaysia and especially, Ambon, Indonesia, is probably linked to a shift in these taxa to a fly-pollinated system. © 2018 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

Orientation of colonized sand flies Phlebotomus papatasi, P. duboscqi, and Lutzomyia longipalpis (Diptera: Psychodidae) to diverse honeys using a 3-chamber in-line olfactometer.

PubMed

Wasserberg, G; Kirsch, P; Rowton, E D

2014-06-01

A 3-chamber in-line olfactometer designed for use with sand flies is described and tested as a high-throughput method to screen honeys for attractiveness to Phlebotomus papatasi (four geographic isolates), P. duboscqi (two geographic isolates), and Lutzomyia longipalpis maintained in colonies at the Walter Reed Army Institute of Research. A diversity of unifloral honey odors were evaluated as a proxy for the natural floral odors that sand flies may use in orientation to floral sugar sources in the field. In the 3-chamber in-line olfactometer, the choice modules come directly off both sides of the release area instead of angling away as in the Y-tube olfactometer. Of the 25 honeys tested, five had a significant attraction for one or more of the sand fly isolates tested. This olfactometer and high-throughput method has utility for evaluating a diversity of natural materials with unknown complex odor blends that can then be down-selected for further evaluation in wind tunnels and/or field scenarios. © 2014 The Society for Vector Ecology.

Fly-ash geo-polymer foamed concrete

NASA Astrophysics Data System (ADS)

Kargin, Aleksey; Baev, Vladimir; Mashkin, Nikolay

2017-01-01

In recent years, the interest of researchrs in using fly-ash as a raw material for the geo-polymer synthesis is increasing. Kuzbass region (in Russia) has a large amount of ash wastes generated, which defined the relevace of the study performed in this paper. Results of investigating load-bearing capacity of structural insulating material produced by geo-polymerization of fly-ash of Kemerovo hydro-electric power plant with the addition of complex activator are described in the paper. Hydrogen peroxide solution was used as the foaming agent. The activation time, the temperature of isothermal holding and hardening in normal conditions for all samples were constant. The compressive strength and the mean density of geo-polymer foamed concrete were determined. The influence of the material composition on its properties was revealed. It is found that of the geo-polymer foamed concrete with the optimum composition has hardness of 1,1-3,5 MPa at the density of 400 to 900 kg/m3. Thus, the production of the fly-ash geo-polymer concretes and mortars is feasible, justified and promising.

Handling qualities of a wide-body transport airplane utilizing Pitch Active Control Systems (PACS) for relaxed static stability application

NASA Technical Reports Server (NTRS)

Grantham, William D.; Person, Lee H., Jr.; Brown, Philip W.; Becker, Lawrence E.; Hunt, George E.; Rising, J. J.; Davis, W. J.; Willey, C. S.; Weaver, W. A.; Cokeley, R.

1985-01-01

Piloted simulation studies have been conducted to evaluate the effectiveness of two pitch active control systems (PACS) on the flying qualities of a wide-body transport airplane when operating at negative static margins. These two pitch active control systems consisted of a simple 'near-term' PACS and a more complex 'advanced' PACS. Eight different flight conditions, representing the entire flight envelope, were evaluated with emphasis on the cruise flight conditions. These studies were made utilizing the Langley Visual/Motion Simulator (VMS) which has six degrees of freedom. The simulation tests indicated that (1) the flying qualities of the baseline aircraft (PACS off) for the cruise and other high-speed flight conditions were unacceptable at center-of-gravity positions aft of the neutral static stability point; (2) within the linear static stability flight envelope, the near-term PACS provided acceptable flying qualities for static stabilty margins to -3 percent; and (3) with the advanced PACS operative, the flying qualities were demonstrated to be good (satisfactory to very acceptable) for static stabilty margins to -20 percent.

On-the-fly scheduling as a manifestation of partial-order planning and dynamic task values.

PubMed

Hannah, Samuel D; Neal, Andrew

2014-09-01

The aim of this study was to develop a computational account of the spontaneous task ordering that occurs within jobs as work unfolds ("on-the-fly task scheduling"). Air traffic control is an example of work in which operators have to schedule their tasks as a partially predictable work flow emerges. To date, little attention has been paid to such on-the-fly scheduling situations. We present a series of discrete-event models fit to conflict resolution decision data collected from experienced controllers operating in a high-fidelity simulation. Our simulations reveal air traffic controllers' scheduling decisions as examples of the partial-order planning approach of Hayes-Roth and Hayes-Roth. The most successful model uses opportunistic first-come-first-served scheduling to select tasks from a queue. Tasks with short deadlines are executed immediately. Tasks with long deadlines are evaluated to assess whether they need to be executed immediately or deferred. On-the-fly task scheduling is computationally tractable despite its surface complexity and understandable as an example of both the partial-order planning strategy and the dynamic-value approach to prioritization.

MotD of Sinorhizobium meliloti and Related α-Proteobacteria Is the Flagellar-Hook-Length Regulator and Therefore Reassigned as FliK

PubMed Central

Eggenhofer, Elke; Rachel, Reinhard; Haslbeck, Martin; Scharf, Birgit

2006-01-01

The flagella of the soil bacterium Sinorhizobium meliloti differ from the enterobacterial paradigm in the complex filament structure and modulation of the flagellar rotary speed. The mode of motility control in S. meliloti has a molecular corollary in two novel periplasmic motility proteins, MotC and MotE, that are present in addition to the ubiquitous MotA/MotB energizing proton channel. A fifth motility gene is located in the mot operon downstream of the motB and motC genes. Its gene product was originally designated MotD, a cytoplasmic motility protein having an unknown function. We report here reassignment of MotD as FliK, the regulator of flagellar hook length. The FliK gene is one of the few flagellar genes not annotated in the contiguous flagellar regulon of S. meliloti. Characteristic for its class, the 475-residue FliK protein contains a conserved, compactly folded Flg hook domain in its carboxy-terminal region. Deletion of fliK leads to formation of prolonged flagellar hooks (polyhooks) with missing filament structures. Extragenic suppressor mutations all mapped in the cytoplasmic region of the transmembrane export protein FlhB and restored assembly of a flagellar filament, and thus motility, in the presence of polyhooks. The structural properties of FliK are consistent with its function as a substrate specificity switch of the flagellar export apparatus for switching from rod/hook-type substrates to filament-type substrates. PMID:16513744

A computational study of hydrogen-bonded X3CH⋯YZ (X = Cl, F, NC; YZ = FLi, BF, CO, N2) complexes

NASA Astrophysics Data System (ADS)

McDowell, Sean A. C.

2018-03-01

An MP2/6-311++G(3df,3pd) computational study of a series of hydrogen-bonded complexes X3CH⋯YZ (X = Cl, F, NC; YZ = FLi, BF, CO, N2) was undertaken to assess the trends in the relative stability and other molecular properties with variation of both the X group and the chemical hardness of the Y atom of YZ. The red- and blue-shifting propensities of the proton donor X3CH were investigated by considering the Csbnd H bond length change and its associated vibrational frequency shift. The proton donor Cl3CH, which has a positive dipole moment derivative with respect to Csbnd H bond extension, tends to form red-shifted complexes, this tendency being modified by the hardness (and dipole moment) associated with the proton acceptor. On the other hand, F3CH has a negative dipole moment derivative and tends to form blue-shifted complexes, suggesting that as X becomes more electron-withdrawing, the proton donor should have a negative dipole moment derivative and form blue-shifted complexes. Surprisingly, the most polar proton donor (NC)3CH was found to have a positive dipole moment derivative and produces red-shifted complexes. A perturbative model was found useful in rationalizing the trends for the Csbnd H bond length change and associated frequency shift.

Solidification/stabilization of ASR fly ash using Thiomer material: Optimization of compressive strength and heavy metals leaching.

PubMed

Baek, Jin Woong; Choi, Angelo Earvin Sy; Park, Hung Suck

2017-12-01

Optimization studies of a novel and eco-friendly construction material, Thiomer, was investigated in the solidification/stabilization of automobile shredded residue (ASR) fly ash. A D-optimal mixture design was used to evaluate and optimize maximum compressive strength and heavy metals leaching by varying Thiomer (20-40wt%), ASR fly ash (30-50wt%) and sand (20-40wt%). The analysis of variance was utilized to determine the level of significance of each process parameters and interactions. The microstructure of the solidified materials was taken from a field emission-scanning electron microscopy and energy dispersive X-ray spectroscopy that confirmed successful Thiomer solidified ASR fly ash due to reduced pores and gaps in comparison with an untreated ASR fly ash. The X-ray diffraction detected the enclosed materials on the ASR fly ash primarily contained sulfur associated crystalline complexes. Results indicated the optimal conditions of 30wt% Thiomer, 30wt% ASR fly ash and 40wt% sand reached a compressive strength of 54.9MPa. For the optimum results in heavy metals leaching, 0.0078mg/LPb, 0.0260mg/L Cr, 0.0007mg/LCd, 0.0020mg/L Cu, 0.1027mg/L Fe, 0.0046mg/L Ni and 0.0920mg/L Zn were leached out, being environmentally safe due to being substantially lower than the Korean standard leaching requirements. The results also showed that Thiomer has superiority over the commonly used Portland cement asa binding material which confirmed its potential usage as an innovative approach to simultaneously synthesize durable concrete and satisfactorily pass strict environmental regulations by heavy metals leaching. Copyright © 2017 Elsevier Ltd. All rights reserved.

Flight control of fruit flies: dynamic response to optic flow and headwind.

PubMed

Lawson, Kiaran K K; Srinivasan, Mandyam V

2017-06-01

Insects are magnificent fliers that are capable of performing many complex tasks such as speed regulation, smooth landings and collision avoidance, even though their computational abilities are limited by their small brain. To investigate how flying insects respond to changes in wind speed and surrounding optic flow, the open-loop sensorimotor response of female Queensland fruit flies ( Bactrocera tryoni ) was examined. A total of 136 flies were exposed to stimuli comprising sinusoidally varying optic flow and air flow (simulating forward movement) under tethered conditions in a virtual reality arena. Two responses were measured: the thrust and the abdomen pitch. The dynamics of the responses to optic flow and air flow were measured at various frequencies, and modelled as a multicompartment linear system, which accurately captured the behavioural responses of the fruit flies. The results indicate that these two behavioural responses are concurrently sensitive to changes of optic flow as well as wind. The abdomen pitch showed a streamlining response, where the abdomen was raised higher as the magnitude of either stimulus was increased. The thrust, in contrast, exhibited a counter-phase response where maximum thrust occurred when the optic flow or wind flow was at a minimum, indicating that the flies were attempting to maintain an ideal flight speed. When the changes in the wind and optic flow were in phase (i.e. did not contradict each other), the net responses (thrust and abdomen pitch) were well approximated by an equally weighted sum of the responses to the individual stimuli. However, when the optic flow and wind stimuli were presented in counterphase, the flies seemed to respond to only one stimulus or the other, demonstrating a form of 'selective attention'. © 2017. Published by The Company of Biologists Ltd.

Virtual Tour of RHIC

ScienceCinema

Brookhaven Lab

2017-12-09

An animation that follows polarized protons as they travel through the Relativistic Heavy Ion Collider (RHIC) accelerator complex to the experiments. The arrows indicate the direction of each proton's spin. The animation concludes with a fly-by of the RHI

Alkali-activated complex binders from class C fly ash and Ca-containing admixtures.

PubMed

Guo, Xiaolu; Shi, Huisheng; Chen, Liming; Dick, Warren A

2010-01-15

Processes that maximize utilization of industrial solid wastes are greatly needed. Sodium hydroxide and sodium silicate solution were used to create alkali-activated complex binders (AACBs) from class C fly ash (CFA) and other Ca-containing admixtures including Portland cement (PC), flue gas desulfurization gypsum (FGDG), and water treatment residual (WTR). Specimens made only from CFA (CFA100), or the same fly ash mixed with 40 wt% PC (CFA60-PC40), with 10 wt% FGDG (CFA90-FGDG10), or with 10 wt% WTR (CFA90-WTR10) had better mechanical performance compared to binders using other mix ratios. The maximum compressive strength of specimens reached 80.0 MPa. Geopolymeric gel, sodium polysilicate zeolite, and hydrated products coexist when AACB reactions occur. Ca from CFA, PC, and WTR precipitated as Ca(OH)(2), bonded in geopolymers to obtain charge balance, or reacted with dissolved silicate and aluminate species to form calcium silicate hydrate (C-S-H) gel. However, Ca from FGDG probably reacted with dissolved silicate and aluminate species to form ettringite. Utilization of CFA and Ca-containing admixtures in AACB is feasible. These binders may be widely utilized in various applications such as in building materials and for solidification/stabilization of other wastes, thus making the wastes more environmentally benign.

Bumblebees minimize control challenges by combining active and passive modes in unsteady winds

NASA Astrophysics Data System (ADS)

Ravi, Sridhar; Kolomenskiy, Dmitry; Engels, Thomas; Schneider, Kai; Wang, Chun; Sesterhenn, Jörn; Liu, Hao

2016-10-01

The natural wind environment that volant insects encounter is unsteady and highly complex, posing significant flight-control and stability challenges. It is critical to understand the strategies insects employ to safely navigate in natural environments. We combined experiments on free flying bumblebees with high-fidelity numerical simulations and lower-order modeling to identify the mechanics that mediate insect flight in unsteady winds. We trained bumblebees to fly upwind towards an artificial flower in a wind tunnel under steady wind and in a von Kármán street formed in the wake of a cylinder. Analysis revealed that at lower frequencies in both steady and unsteady winds the bees mediated lateral movement with body roll - typical casting motion. Numerical simulations of a bumblebee in similar conditions permitted the separation of the passive and active components of the flight trajectories. Consequently, we derived simple mathematical models that describe these two motion components. Comparison between the free-flying live and modeled bees revealed a novel mechanism that enables bees to passively ride out high-frequency perturbations while performing active maneuvers at lower frequencies. The capacity of maintaining stability by combining passive and active modes at different timescales provides a viable means for animals and machines to tackle the challenges posed by complex airflows.

Characterisation of the chemical profiles of Brazilian and Andean morphotypes belonging to the Anastrepha fraterculus complex (Diptera, Tephritidae)

PubMed Central

Vaníčková, Lucie; Břízová, Radka; Pompeiano, Antonio; Ferreira, Luana Lima; de Aquino, Nathaly Costa; Tavares, Raphael de Farias; Rodriguez, Laura D.; Mendonça, Adriana de Lima; Canal, Nelson Augusto; do Nascimento, Ruth Rufino

2015-01-01

Abstract Fruit fly sexual behaviour is directly influenced by chemical and non-chemical cues that play important roles in reproductive isolation. The chemical profiles of pheromones and cuticular hydrocarbons (CHs) of eight fruit fly populations of the Andean, Brazilian-1 and Brazilian-3 morphotypes of the Anastrepha fraterculus cryptic species complex originating from Colombia (four populations) and Brazil (four populations) were analysed using two-dimensional gas chromatography with mass spectrometric detection. The resulting chemical diversity data were studied using principal component analyses. Andean morphotypes could be discriminated from the Brazilian-1 and Brazilian-3 morphotypes by means of male-borne pheromones and/or male and female CH profiles. The Brazilian-1 and Brazilian-3 morphotypes were found to be monophyletic. The use of chemical profiles as species- and sex-specific signatures for cryptic species separations is discussed. PMID:26798260

Effect of salinity on the precipitation of dissolved metals in the wastewater that produced during fly ash disposal

NASA Astrophysics Data System (ADS)

Lv, Lina; Yang, Yanling; Tian, Junguo; Li, Yaojian; Li, Jun; Yan, Shengjun

2018-02-01

In this study, a salinity wastewater was produced during the fly ash treatment in the waste incineration plant. Chemical precipitation method was applied for heavy metals removal in the salinity wastewater. The effect of salinity on the removal of dissolved heavy metal ions (Zn2+, Cu2+, Pb2+, Ni2+ and Cd2+) was studied, especially on the removal of Pb2+ and Cd2+. Because of the formation of [PbCl3]- and [PbCl4]2- complexes, the residual concentration of dissolved Pb2+ increased from 0.02 mg/L to 4.08 mg/L, as the NaCl concentration increased from 0 % to 10 %. And the residual concentration of dissolved Cd2+ increased from 0.02 mg/L to 1.39 mg/L, due to the formation of [CdCl3]-, [CdCl4]2- and [CdCl6]4- complexes.

Genetics on the Fly: A Primer on the Drosophila Model System

PubMed Central

Hales, Karen G.; Korey, Christopher A.; Larracuente, Amanda M.; Roberts, David M.

2015-01-01

Fruit flies of the genus Drosophila have been an attractive and effective genetic model organism since Thomas Hunt Morgan and colleagues made seminal discoveries with them a century ago. Work with Drosophila has enabled dramatic advances in cell and developmental biology, neurobiology and behavior, molecular biology, evolutionary and population genetics, and other fields. With more tissue types and observable behaviors than in other short-generation model organisms, and with vast genome data available for many species within the genus, the fly’s tractable complexity will continue to enable exciting opportunities to explore mechanisms of complex developmental programs, behaviors, and broader evolutionary questions. This primer describes the organism’s natural history, the features of sequenced genomes within the genus, the wide range of available genetic tools and online resources, the types of biological questions Drosophila can help address, and historical milestones. PMID:26564900

[Model aeroplanes: a not to be ignored source of complex injuries].

PubMed

Laback, C; Vasilyeva, A; Rappl, T; Lumenta, D; Giunta, R E; Kamolz, L

2013-12-01

With the incidence of work-related injuries decreasing, we continue to observe an unchanged trend in leisure-related accidents. As in any other hobby, model flying devices bear the risk for accidents among builders and flyers ranging from skin lacerations to complicated and even life-threatening injuries. The fast-moving razor-sharp propeller blades predominantly cause trauma to the hands and fingers resulting in typical multiple parallel skin injuries also affecting structures deep to the dermis (e. g., tendons, vessels and nerves). The resultant clinical management involves complex reconstructive surgical procedures and prolonged rehabilitative follow-up. Improving the legal framework (e. g., warnings by the manufacturer) on the one hand, providing informative action and sensitising those affected on the other, should form a basis for an altered prevention strategy to reduce model flying device-related injuries in the future. © Georg Thieme Verlag KG Stuttgart · New York.

Evaluation of microwave landing system approaches in a wide-body transport simulator

NASA Technical Reports Server (NTRS)

Summers, L. G.; Feather, J. B.

1992-01-01

The objective of this study was to determine the suitability of flying complex curved approaches using the microwave landing system (MLS) with a wide-body transport aircraft. Fifty pilots in crews of two participated in the evaluation using a fixed-base simulator that emulated an MD-11 aircraft. Five approaches, consisting of one straight-in approach and four curved approaches, were flown by the pilots using a flight director. The test variables include the following: (1) manual and autothrottles; (2) wind direction; and (3) type of navigation display. The navigation display was either a map or a horizontal situation indicator (HSI). A complex wind that changed direction and speed with altitude, and included moderate turbulence, was used. Visibility conditions were Cat 1 or better. Subjective test data included pilot responses to questionnaires and pilot comments. Objective performance data included tracking accuracy, position error at decision height, and control activity. Results of the evaluation indicate that flying curved MLS approaches with a wide-body transport aircraft is operationally acceptable, depending upon the length of the final straight segment and the complexity of the approach.

The Influence of Sex and Fly Species on the Development of Trypanosomes in Tsetse Flies

PubMed Central

Peacock, Lori; Ferris, Vanessa; Bailey, Mick; Gibson, Wendy

2012-01-01

Unlike other dipteran disease vectors, tsetse flies of both sexes feed on blood and transmit pathogenic African trypanosomes. During transmission, Trypanosoma brucei undergoes a complex cycle of proliferation and development inside the tsetse vector, culminating in production of infective forms in the saliva. The insect manifests robust immune defences throughout the alimentary tract, which eliminate many trypanosome infections. Previous work has shown that fly sex influences susceptibility to trypanosome infection as males show higher rates of salivary gland (SG) infection with T. brucei than females. To investigate sex-linked differences in the progression of infection, we compared midgut (MG), proventriculus, foregut and SG infections in male and female Glossina morsitans morsitans. Initially, infections developed in the same way in both sexes: no difference was observed in numbers of MG or proventriculus infections, or in the number and type of developmental forms produced. Female flies tended to produce foregut migratory forms later than males, but this had no detectable impact on the number of SG infections. The sex difference was not apparent until the final stage of SG invasion and colonisation, showing that the SG environment differs between male and female flies. Comparison of G. m. morsitans with G. pallidipes showed a similar, though less pronounced, sex difference in susceptibility, but additionally revealed very different levels of trypanosome resistance in the MG and SG. While G. pallidipes was more refractory to MG infection, a very high proportion of MG infections led to SG infection in both sexes. It appears that the two fly species use different strategies to block trypanosome infection: G. pallidipes heavily defends against initial establishment in the MG, while G. m. morsitans has additional measures to prevent trypanosomes colonising the SG, particularly in female flies. We conclude that the tsetse-trypanosome interface works differently in G. m. morsitans and G. pallidipes. PMID:22348165

How bumblebees use lateral and ventral optic flow cues for position control in environments of different proximity.

PubMed

Linander, Nellie; Baird, Emily; Dacke, Marie

2017-05-01

Flying insects frequently navigate through environments of different complexity. In this study, buff-tailed bumblebees (Bombus terrestris L.) were trained to fly along tunnels of different widths, from 60 to 240 cm. In tunnel widths of 60 and 120 cm, bumblebees control their lateral position by balancing the magnitude of translational optic flow experienced in the lateral visual field of each eye. In wider tunnels, bumblebees use translational optic flow cues in the ventral visual field to control their lateral position and to steer along straight tracks. Our results also suggest that bumblebees prefer to fly over surfaces that provide strong ventral optic flow cues, rather than over featureless ones. Together, these strategies allow bumblebees to minimize the risk of collision and to maintain relatively straight flight paths in a broad range of environments.

Hybrid quantum gates between flying photon and diamond nitrogen-vacancy centers assisted by optical microcavities

PubMed Central

Wei, Hai-Rui; Lu Long, Gui

2015-01-01

Hybrid quantum gates hold great promise for quantum information processing since they preserve the advantages of different quantum systems. Here we present compact quantum circuits to deterministically implement controlled-NOT, Toffoli, and Fredkin gates between a flying photon qubit and diamond nitrogen-vacancy (NV) centers assisted by microcavities. The target qubits of these universal quantum gates are encoded on the spins of the electrons associated with the diamond NV centers and they have long coherence time for storing information, and the control qubit is encoded on the polarizations of the flying photon and can be easily manipulated. Our quantum circuits are compact, economic, and simple. Moreover, they do not require additional qubits. The complexity of our schemes for universal three-qubit gates is much reduced, compared to the synthesis with two-qubit entangling gates. These schemes have high fidelities and efficiencies, and they are feasible in experiment. PMID:26271899

Angular velocity integration in a fly heading circuit.

PubMed

Turner-Evans, Daniel; Wegener, Stephanie; Rouault, Hervé; Franconville, Romain; Wolff, Tanya; Seelig, Johannes D; Druckmann, Shaul; Jayaraman, Vivek

2017-05-22

Many animals maintain an internal representation of their heading as they move through their surroundings. Such a compass representation was recently discovered in a neural population in the Drosophila melanogaster central complex, a brain region implicated in spatial navigation. Here, we use two-photon calcium imaging and electrophysiology in head-fixed walking flies to identify a different neural population that conjunctively encodes heading and angular velocity, and is excited selectively by turns in either the clockwise or counterclockwise direction. We show how these mirror-symmetric turn responses combine with the neurons' connectivity to the compass neurons to create an elegant mechanism for updating the fly's heading representation when the animal turns in darkness. This mechanism, which employs recurrent loops with an angular shift, bears a resemblance to those proposed in theoretical models for rodent head direction cells. Our results provide a striking example of structure matching function for a broadly relevant computation.

Nutrient-Dependent Impact of Microbes on Drosophila suzukii Development.

PubMed

Bing, XiaoLi; Gerlach, Joseph; Loeb, Gregory; Buchon, Nicolas

2018-03-20

Drosophila suzukii Matsumura is an invasive species of vinegar fly that has become a prominent pest of berries and other soft-skinned fruits. Unlike most other Drosophila species, female D. suzukii flies lay their eggs in ripening and ripe fruits and larvae develop within the fruit. To understand how D. suzukii larvae utilize ripe and ripening fruits, which usually have low levels of protein, we investigated the microbiota of field-captured and laboratory-reared D. suzukii flies and further examined the combined influence of diet and microbes on host fitness. Field-captured flies were associated with diverse microbiota, which varied significantly with sampling location and season. In contrast, laboratory-reared flies possessed strikingly lower bacterial abundance and diversity. A comparison of conventionally reared (CR) and germ-free (GF) flies revealed that the microbiota of D. suzukii does not alter its development significantly but decreases its life span under conditions of a nutrient-sufficient diet. However, the microbiota is essential for D. suzukii development on strawberry-based or blueberry-based fruit diets. This developmental failure could be rescued by reassociation with single bacterial or fungal species or by the addition of a high quantity of heat-killed microbes. In addition, we found that proteins are limiting with respect to fly development on fruit-based diets and that GF flies show signs of protein starvation. Taken together, our study results demonstrate that the microbiota provides key proteins required for the development of D. suzukii reared on fresh fruit. Our work shows that the impact of microbes on fly fitness depends strongly on nutritional conditions. IMPORTANCE Animals are commonly associated with specific microbes, which play important roles in host development and fitness. However, little information about the function of microbes has been available for the important invasive pest Drosophila suzukii , also known as Spotted wing drosophila. Our study results demonstrate that the abundance and structure of microbiota in D. suzukii are strongly affected by the environment, where microbes have variable roles depending on the nutritional situation. For instance, we found that the presence of microbes is deleterious for flies growing on a protein-rich diet and yet is beneficial for flies growing on a diet of protein-poor fruits. Additionally, germ-free flies must feed on microbes to obtain the necessary protein for larval development on strawberries and blueberries. Our report validates the complexity seen in host-microbe interactions and may provide information useful for D. suzukii pest control. Copyright © 2018 Bing et al.

Neural Action Fields for Optic Flow Based Navigation: A Simulation Study of the Fly Lobula Plate Network

PubMed Central

Borst, Alexander; Weber, Franz

2011-01-01

Optic flow based navigation is a fundamental way of visual course control described in many different species including man. In the fly, an essential part of optic flow analysis is performed in the lobula plate, a retinotopic map of motion in the environment. There, the so-called lobula plate tangential cells possess large receptive fields with different preferred directions in different parts of the visual field. Previous studies demonstrated an extensive connectivity between different tangential cells, providing, in principle, the structural basis for their large and complex receptive fields. We present a network simulation of the tangential cells, comprising most of the neurons studied so far (22 on each hemisphere) with all the known connectivity between them. On their dendrite, model neurons receive input from a retinotopic array of Reichardt-type motion detectors. Model neurons exhibit receptive fields much like their natural counterparts, demonstrating that the connectivity between the lobula plate tangential cells indeed can account for their complex receptive field structure. We describe the tuning of a model neuron to particular types of ego-motion (rotation as well as translation around/along a given body axis) by its ‘action field’. As we show for model neurons of the vertical system (VS-cells), each of them displays a different type of action field, i.e., responds maximally when the fly is rotating around a particular body axis. However, the tuning width of the rotational action fields is relatively broad, comparable to the one with dendritic input only. The additional intra-lobula-plate connectivity mainly reduces their translational action field amplitude, i.e., their sensitivity to translational movements along any body axis of the fly. PMID:21305019

Evidence for inversion polymorphism related to sympatric host race formation in the apple maggot fly, Rhagoletis pomonella.

PubMed Central

Feder, Jeffrey L; Roethele, Joseph B; Filchak, Kenneth; Niedbalski, Julie; Romero-Severson, Jeanne

2003-01-01

Evidence suggests that the apple maggot, Rhagoletis pomonella (Diptera: Tephritidae) is undergoing sympatric speciation (i.e., divergence without geographic isolation) in the process of shifting and adapting to a new host plant. Prior to the introduction of cultivated apples (Malus pumila) in North America, R. pomonella infested the fruit of native hawthorns (Crataegus spp.). However, sometime in the mid-1800s the fly formed a sympatric race on apple. The recently derived apple-infesting race shows consistent allele frequency differences from the hawthorn host race for six allozyme loci mapping to three different chromosomes. Alleles at all six of these allozymes correlate with the timing of adult eclosion, an event dependent on the duration of the overwintering pupal diapause. This timing difference differentially adapts the univoltine fly races to an approximately 3- to 4-week difference in the peak fruiting times of apple and hawthorn trees, partially reproductively isolating the host races. Here, we report finding substantial gametic disequilibrium among allozyme and complementary DNA (cDNA) markers encompassing the three chromosomal regions differentiating apple and hawthorn flies. The regions of disequilibrium extend well beyond the previously characterized six allozyme loci, covering substantial portions of chromosomes 1, 2, and 3 (haploid n = 6 in R. pomonella). Moreover, significant recombination heterogeneity and variation in gene order were observed among single-pair crosses for each of the three genomic regions, implying the existence of inversion polymorphism. We therefore have evidence that genes affecting diapause traits involved in host race formation reside within large complexes of rearranged genes. We explore whether these genomic regions (inversions) constitute coadapted gene complexes and discuss the implications of our findings for sympatric speciation in Rhagoletis. PMID:12663534

The effect of peroxiredoxin 4 on fly physiology is a complex interplay of antioxidant and signaling functions

PubMed Central

Radyuk, Svetlana N.; Klichko, Vladimir I.; Michalak, Katarzyna; Orr, William C.

2013-01-01

Peroxiredoxin 4 (Prx4) has been implicated in a wide variety of biological processes, including development, progression of cancer, inflammation, and antioxidant function. The purpose of this study was to provide further insight into its multiple roles at the whole-animal level, using Drosophila. Reduced expression of dPrx4 (up to 90%) resulted in greater sensitivity to oxidative stress, an elevated H2O2 flux, and increases in lipid peroxidation, but no effect on longevity. Overexpression at low levels (<2-fold) gave reduced levels of oxidative damage and tended to show an increase in longevity. Flies expressing dPrx4 globally at high levels (>5-fold) had a dramatically reduced life span (by 20–80%) and increased apoptosis. Analysis of these overexpressors revealed an aberrant redistribution of the dPrx4 protein from the endoplasmic reticulum (ER) to cytosol and hemolymph. In addition to the known proapoptotic effects of the cytosolic form of dPrx4, dPrx4 overexpression triggered an NF-κB-mediated proinflammatory response, similar to that observed in cells under ER stress or when microbially challenged. Finally, we provide the first evidence that dPrx4, on secretion into the hemolymph, elicits a JAK/STAT-mediated response. The effects on fly survival and homeostasis appear to represent a combination of differential effects dictated in large part by dPrx4 subcellular and tissue-specific localization.—Radyuk, S. N., Klichko, V. I., Michalak, K., Orr, W. C. The effect of peroxiredoxin 4 on fly physiology is a complex interplay of antioxidant and signaling functions. PMID:23271054

A precedence effect resolves phantom sound source illusions in the parasitoid fly Ormia ochracea

PubMed Central

Lee, Norman; Elias, Damian O.; Mason, Andrew C.

2009-01-01

Localizing individual sound sources under reverberant environmental conditions can be a challenge when the original source and its acoustic reflections arrive at the ears simultaneously from different paths that convey ambiguous directional information. The acoustic parasitoid fly Ormia ochracea (Diptera: Tachinidae) relies on a pair of ears exquisitely sensitive to sound direction to localize the 5-kHz tone pulsatile calling song of their host crickets. In nature, flies are expected to encounter a complex sound field with multiple sources and their reflections from acoustic clutter potentially masking temporal information relevant to source recognition and localization. In field experiments, O. ochracea were lured onto a test arena and subjected to small random acoustic asymmetries between 2 simultaneous sources. Most flies successfully localize a single source but some localize a ‘phantom’ source that is a summed effect of both source locations. Such misdirected phonotaxis can be elicited reliably in laboratory experiments that present symmetric acoustic stimulation. By varying onset delay between 2 sources, we test whether hyperacute directional hearing in O. ochracea can function to exploit small time differences to determine source location. Selective localization depends on both the relative timing and location of competing sources. Flies preferred phonotaxis to a forward source. With small onset disparities within a 10-ms temporal window of attention, flies selectively localize the leading source while the lagging source has minimal influence on orientation. These results demonstrate the precedence effect as a mechanism to overcome phantom source illusions that arise from acoustic reflections or competing sources. PMID:19332794

DNA Barcoding Reveals Hidden Diversity of Sand Flies (Diptera: Psychodidae) at Fine and Broad Spatial Scales in Brazilian Endemic Regions for Leishmaniasis.

PubMed

Rodrigues, Bruno Leite; Carvalho-Costa, Luís Fernando; Pinto, Israel de Souza; Rebêlo, José Manuel Macário

2018-03-17

Sand fly (Diptera: Psychodidae) taxonomy is complex and time-consuming, which hampers epidemiological efforts directed toward controlling leishmaniasis in endemic regions such as northeastern Brazil. Here, we used a fragment of the mitochondrial cytochrome c oxidase I (COI) gene to identify sand fly species in Maranhão State (northeastern Brazil) and to assess cryptic diversity occurring at different spatial scales. For this, we obtained 148 COI sequences of 15 sand fly species (10 genera) from Maranhão (fine spatial scale), and joined them to COI sequences from other Brazilian localities (distant about 2,000 km from Maranhão, broad spatial scale) available in GenBank. We revealed cases of cryptic diversity in sand flies both at fine (Lutzomyia longipalpis (Lutz and Neiva) and Evandromyia termitophila (Martins, Falcão and Silva)) and broad spatial scales (Migonemyia migonei (França), Pressatia choti (Floch and Abonnenc), Psychodopygus davisi (Root), Sciopemyia sordellii (Shannon and Del Ponte), and Bichromomyia flaviscutellata (Mangabeira)). We argue that in the case of Bi. flaviscutellata, the cryptic diversity is associated with a putative new species. Cases in which DNA taxonomy was not as effective as morphological identification possibly involved recent speciation and/or introgressive hybridization, highlighting the need for integrative approaches to identify some sand fly species. Finally, we provide the first barcode sequences for four species (Brumptomyia avellari (Costa Lima), Evandromyia infraspinosa (Mangabeira), Evandromyia evandroi (Costa Lima and Antunes), and Psychodopygus complexus (Mangabeira)), which will be useful for further molecular identification of neotropical species.

Diversity of phlebotomine sand flies (Diptera: Psychodidae) in Ibitipoca State Park, Minas Gerais, Brazil.

PubMed

Carvalho, Gustavo Mayr de Lima; De Vasconcelos, Fernanda Bernardes; Da Silva, Daniela Gonçalves; Botelho, Helbert Antônio; Filho, José Dilermando Andrade

2011-07-01

Leishmaniasis is a complex of zoonotic diseases that are endemic to many Brazilian states. They are transmitted to the vertebrates by the bite of the hematophagous female sand fly (Diptera: Psychodidae) vectors. Despite the increasing occurrence of visceral and cutaneous leishmaniasis cases in large urban centers, their transmission continues to occur primarily in a wild environment and may be associated with professional activities, ecotourism activities, or both. This study investigates the ecological parameters of the sand flies present in Ibitipoca State Park, Minas Gerais, Brazil. During 2009, systematic collections of sand flies were made monthly using HP light traps installed at five sites, including three natural settings (a cave, riparian vegetation, and a rain forest), the tourist and researchers' accommodations, and a surrounding domestic livestock area. In total, 161 sand flies (seven species) were collected, the most abundant, particularly in the surrounding domestic livestock area, being Lutzomyia (Psychodopygus) lloydi (Antunes, 1937). Furthermore, a previously unidentified Lutzomyia (Sciopemyia) sp. was prevalent in the cave environment. There are no existing records of the occurrence of leishmaniasis in Ibitipoca State Park; however, the some species of the subgenus Psychodopygus are known vectors of Leishmania spp in Brazil. Hence, the presence of a species of this genus in areas surrounding the park may represent a risk to ecotourism and the local inhabitants. Our study shows the importance of regular monitoring of the various areas used by humans to determine the distribution and spread of sand fly vectors for preventive management to forestall potential risk to health and consequent effect on ecotourists.

Negative regulatory loci coupling flagellin synthesis to flagellar assembly in Salmonella typhimurium.

PubMed Central

Gillen, K L; Hughes, K T

1991-01-01

The complex regulation of flagellin gene expression in Salmonella typhimurium was characterized in vivo by using lac transcriptional fusions to the two flagellin structural genes (fliC [H1] and fljB [H2]). Phase variation was measured as the rate of switching of flagellin gene expression. Switching frequencies varied from 1/500 per cell per generation to 1/10,000 per cell per generation depending on the particular insertion and the direction of switching. There is a 4- to 20-fold bias in favor of switching from the fljB(On) to the fljB(Off) orientation. Random Tn10dTc insertions were isolated which failed to express flagellin. While most of these insertions mapped to loci known to be required for flagellin expression, several new loci were identified. The presence of functional copies of all of the genes responsible for complete flagellar assembly, except the hook-associated proteins (flgK, flgL, and fliD gene products), were required for expression of the fliC or fljB flagellin genes. Two novel loci involved in negative regulation of fliC and fljB in fla mutant backgrounds were identified. One of these loci, designated the flgR locus, mapped to the flg operon at 23 min on the Salmonella linkage map. An flgR insertion mutation resulted in relief of repression of the fliC and fljB genes in all fla mutant backgrounds except for mutants in the positive regulatory loci (flhC, flhD, and fliA genes). PMID:1848842

Variation of tsetse fly abundance in relation to habitat and host presence in the Maasai Steppe, Tanzania.

PubMed

Ngonyoka, Anibariki; Gwakisa, Paul S; Estes, Anna B; Nnko, Happiness J; Hudson, Peter J; Cattadori, Isabella M

2017-06-01

Human activities modify ecosystem structure and function and can also alter the vital rates of vectors and thus the risk of infection with vector-borne diseases. In the Maasai Steppe ecosystem of northern Tanzania, local communities depend on livestock and suitable pasture that is shared with wildlife, which can increase tsetse abundance and the risk of trypanosomiasis. We monitored the monthly tsetse fly abundance adjacent to Tarangire National Park in 2014-2015 using geo-referenced, baited epsilon traps. We examined the effect of habitat types and vegetation greenness (NDVI) on the relative abundance of tsetse fly species. Host availability (livestock and wildlife) was also recorded within 100×100 m of each trap site. The highest tsetse abundance was found in the ecotone between Acacia-Commiphora woodland and grassland, and the lowest in riverine woodland. Glossina swynnertoni was the most abundant species (68%) trapped throughout the entire study, while G. pallidipes was the least common (4%). Relative species abundance was negatively associated with NDVI, with greatest abundance observed in the dry season. The relationship with the abundance of wildlife and livestock was more complex, as we found positive and negative associations depending on the host and fly species. While habitat is important for tsetse distribution, hosts also play a critical role in affecting fly abundance and, potentially, trypanosomiasis risk. © 2017 The Society for Vector Ecology.

Identification of host fruit volatiles from flowering dogwood (Cornus florida) attractive to dogwood-origin Rhagoletis pomonella flies.

PubMed

Nojima, Satoshi; Linn, Charles; Roelofs, Wendell

2003-10-01

Solid-phase microextraction and gas chromatography coupled with electroantennographic detection were used to identify volatiles from fruit of flowering dogwood, Cornus florida, as key attractants for Rhagoletis pomonella flies originating from dogwood fruit. A six-component blend containing ethyl acetate (54.9%), 3-methylbutan-1-ol (27.5%), isoamyl acetate (0.9%), dimethyl trisulfide (1.9%), 1-octen-3-ol (9.1%), and beta-caryophyllene (5.8%) was identified from flowering dogwood fruit that gave consistent EAD activity. In a flight tunnel assay there was no significant difference in the response of individual dogwood flies exhibiting upwind anemotactic flight to volatile extracts from dogwood fruit and the six-component synthetic mixture. Dogwood flies also displayed significantly greater levels of upwind flight to sources with the dogwood volatile blend than with previously identified volatile blends from domestic apple or hawthorn fruit. Selected subtraction assays showed that the three-component mixture of 3-methylbutan-1-ol, 1-octen-3-ol, and beta-caryophyllene elicited levels of upwind flight to the source equivalent to the six-component mixture. Our study adds to previous ones showing that populations of Rhagoletis pomonella flies infesting apple, hawthorn, and flowering dogwood fruit are attracted to unique mixtures of fruit volatiles, supporting the hypothesis that host fruit odors could be key traits in sympatric host shifts and establishing host fidelity within members of the Rhagoletis pomonella species complex.

Spatial distribution of sand fly species (Psychodidae: Phlebtominae), ecological niche, and climatic regionalization in zoonotic foci of cutaneous leishmaniasis, southwest of Iran.

PubMed

Ebrahimi, Sahar; Bordbar, Ali; Rastaghi, Ahmad R Esmaeili; Parvizi, Parviz

2016-06-01

Cutaneous leishmaniasis (CL) is a complex vector-borne disease caused by Leishmania parasites that are transmitted by the bite of several species of infected female phlebotomine sand flies. Monthly factor analysis of climatic variables indicated fundamental variables. Principal component-based regionalization was used for recognition of climatic zones using a clustering integrated method that identified five climatic zones based on factor analysis. To investigate spatial distribution of the sand fly species, the kriging method was used as an advanced geostatistical procedure in the ArcGIS modeling system that is beneficial to design measurement plans and to predict the transmission cycle in various regions of Khuzestan province, southwest of Iran. However, more than an 80% probability of P. papatasi was observed in rainy and temperate bio-climatic zones with a high potential of CL transmission. Finding P. sergenti revealed the probability of transmission and distribution patterns of a non-native vector of CL in related zones. These findings could be used as models indicating climatic zones and environmental variables connected to sand fly presence and vector distribution. Furthermore, this information is appropriate for future research efforts into the ecology of Phlebotomine sand flies and for the prevention of CL vector transmission as a public health priority. © 2016 The Society for Vector Ecology.

Evolution of insecticide resistance in non-target black flies (Diptera: Simuliidae) from Argentina.

PubMed

Montagna, Cristina Mónica; Gauna, Lidia Ester; D'Angelo, Ana Pechen de; Anguiano, Olga Liliana

2012-06-01

Black flies, a non-target species of the insecticides used in fruit production, represent a severe medical and veterinary problem. Large increases in the level of resistance to the pyrethroids fenvalerate (more than 355-fold) and deltamethrin (162-fold) and a small increase in resistance to the organophosphate azinphos methyl (2-fold) were observed between 1996-2008 in black fly larvae under insecticide pressure. Eventually, no change or a slight variation in insecticide resistance was followed by a subsequent increase in resistance. The evolution of pesticide resistance in a field population is a complex and stepwise process that is influenced by several factors, the most significant of which is the insecticide selection pressure, such as the dose and frequency of application. The variation in insecticide susceptibility within a black fly population in the productive area may be related to changes in fruit-pest control. The frequency of individuals with esterase activities higher than the maximum value determined in the susceptible population increased consistently over the sampling period. However, the insecticide resistance was not attributed to glutathione S-transferase activity. In conclusion, esterase activity in black flies from the productive area is one mechanism underlying the high levels of resistance to pyrethroids, which have been recently used infrequently. These enzymes may be reselected by currently used pesticides and enhance the resistance to these insecticides.

Applying GIS and high performance agent-based simulation for managing an Old World Screwworm fly invasion of Australia.

PubMed

Welch, M C; Kwan, P W; Sajeev, A S M

2014-10-01

Agent-based modelling has proven to be a promising approach for developing rich simulations for complex phenomena that provide decision support functions across a broad range of areas including biological, social and agricultural sciences. This paper demonstrates how high performance computing technologies, namely General-Purpose Computing on Graphics Processing Units (GPGPU), and commercial Geographic Information Systems (GIS) can be applied to develop a national scale, agent-based simulation of an incursion of Old World Screwworm fly (OWS fly) into the Australian mainland. The development of this simulation model leverages the combination of massively data-parallel processing capabilities supported by NVidia's Compute Unified Device Architecture (CUDA) and the advanced spatial visualisation capabilities of GIS. These technologies have enabled the implementation of an individual-based, stochastic lifecycle and dispersal algorithm for the OWS fly invasion. The simulation model draws upon a wide range of biological data as input to stochastically determine the reproduction and survival of the OWS fly through the different stages of its lifecycle and dispersal of gravid females. Through this model, a highly efficient computational platform has been developed for studying the effectiveness of control and mitigation strategies and their associated economic impact on livestock industries can be materialised. Copyright © 2014 International Atomic Energy Agency 2014. Published by Elsevier B.V. All rights reserved.

DNA damage induced by coal dust, fly and bottom ash from coal combustion evaluated using the micronucleus test and comet assay in vitro.

PubMed

Matzenbacher, Cristina Araujo; Garcia, Ana Letícia Hilario; Dos Santos, Marcela Silva; Nicolau, Caroline Cardoso; Premoli, Suziane; Corrêa, Dione Silva; de Souza, Claudia Telles; Niekraszewicz, Liana; Dias, Johnny Ferraz; Delgado, Tânia Valéria; Kalkreuth, Wolfgang; Grivicich, Ivana; da Silva, Juliana

2017-02-15

Coal mining and combustion generating huge amounts of bottom and fly ash are major causes of environmental pollution and health hazards due to the release of polycyclic aromatic hydrocarbons (PAH) and heavy metals. The Candiota coalfield in Rio Grande do Sul, is one of the largest open-cast coal mines in Brazil. The aim of this study was to evaluate genotoxic and mutagenic effects of coal, bottom ash and fly ash samples from Candiota with the comet assay (alkaline and modified version) and micronucleus test using the lung fibroblast cell line (V79). Qualitative and quantitative analysis of PAH and inorganic elements was carried out by High Performance Liquid Chromatography (HPLC) and by Particle-Induced X-ray Emission (PIXE) techniques respectively. The samples demonstrated genotoxic and mutagenic effects. The comet assay modified using DNA-glicosilase formamidopirimidina (FPG) endonuclease showed damage related to oxidative stress mechanisms. The amount of PAHs was higher in fly ash followed by pulverized coal. The amount of inorganic elements was highest in fly ash, followed by bottom ash. It is concluded that the samples induce DNA damage by mechanisms that include oxidative stress, due to their complex composition, and that protective measures have to be taken regarding occupational and environmental hazards. Copyright © 2016 Elsevier B.V. All rights reserved.

Microbiota-induced changes in drosophila melanogaster host gene expression and gut morphology.

PubMed

Broderick, Nichole A; Buchon, Nicolas; Lemaitre, Bruno

2014-05-27

To elucidate mechanisms underlying the complex relationships between a host and its microbiota, we used the genetically tractable model Drosophila melanogaster. Consistent with previous studies, the microbiota was simple in composition and diversity. However, analysis of single flies revealed high interfly variability that correlated with differences in feeding. To understand the effects of this simple and variable consortium, we compared the transcriptome of guts from conventionally reared flies to that for their axenically reared counterparts. Our analysis of two wild-type fly lines identified 121 up- and 31 downregulated genes. The majority of these genes were associated with immune responses, tissue homeostasis, gut physiology, and metabolism. By comparing the transcriptomes of young and old flies, we identified temporally responsive genes and showed that the overall impact of microbiota was greater in older flies. In addition, comparison of wild-type gene expression with that of an immune-deficient line revealed that 53% of upregulated genes exerted their effects through the immune deficiency (Imd) pathway. The genes included not only classic immune response genes but also those involved in signaling, gene expression, and metabolism, unveiling new and unexpected connections between immunity and other systems. Given these findings, we further characterized the effects of gut-associated microbes on gut morphology and epithelial architecture. The results showed that the microbiota affected gut morphology through their impacts on epithelial renewal rate, cellular spacing, and the composition of different cell types in the epithelium. Thus, while bacteria in the gut are highly variable, the influence of the microbiota at large has far-reaching effects on host physiology. The guts of animals are in constant association with microbes, and these interactions are understood to have important roles in animal development and physiology. Yet we know little about the mechanisms underlying the establishment and function of these associations. Here, we used the fruit fly to understand how the microbiota affects host function. Importantly, we found that the microbiota has far-reaching effects on host physiology, ranging from immunity to gut structure. Our results validate the notion that important insights on complex host-microbe relationships can be obtained from the use of a well-established and genetically tractable invertebrate model. Copyright © 2014 Broderick et al.

Path changing methods applied to the 4-D guidance of STOL aircraft.

DOT National Transportation Integrated Search

1971-11-01

Prior to the advent of large-scale commercial STOL service, some challenging navigation and guidance problems must be solved. Proposed terminal area operations may require that these aircraft be capable of accurately flying complex flight paths, and ...

Squirrels cannot live by truffles alone: a closer look at a northwest keystone complex.

Treesearch

Sally Duncan

2004-01-01

Tree squirrels in the Pacific Northwest are part of a keystone complex that includes ectomycorrhizal fungi, Douglas-fir, and spotted owls. All three squirrel species—the northern flying squirrel, the Douglas' squirrel, and the Townsend’s squirrel—consume truffles produced by fungal partners of important tree species. The squirrels then spread the spores of these...

The Talin Head Domain Reinforces Integrin-Mediated Adhesion by Promoting Adhesion Complex Stability and Clustering

PubMed Central

Ellis, Stephanie J.; Lostchuck, Emily; Goult, Benjamin T.; Bouaouina, Mohamed; Fairchild, Michael J.; López-Ceballos, Pablo; Calderwood, David A.; Tanentzapf, Guy

2014-01-01

Talin serves an essential function during integrin-mediated adhesion in linking integrins to actin via the intracellular adhesion complex. In addition, the N-terminal head domain of talin regulates the affinity of integrins for their ECM-ligands, a process known as inside-out activation. We previously showed that in Drosophila, mutating the integrin binding site in the talin head domain resulted in weakened adhesion to the ECM. Intriguingly, subsequent studies showed that canonical inside-out activation of integrin might not take place in flies. Consistent with this, a mutation in talin that specifically blocks its ability to activate mammalian integrins does not significantly impinge on talin function during fly development. Here, we describe results suggesting that the talin head domain reinforces and stabilizes the integrin adhesion complex by promoting integrin clustering distinct from its ability to support inside-out activation. Specifically, we show that an allele of talin containing a mutation that disrupts intramolecular interactions within the talin head attenuates the assembly and reinforcement of the integrin adhesion complex. Importantly, we provide evidence that this mutation blocks integrin clustering in vivo. We propose that the talin head domain is essential for regulating integrin avidity in Drosophila and that this is crucial for integrin-mediated adhesion during animal development. PMID:25393120

Aberrant Axonal Arborization of PDF Neurons Induced by Aβ42-Mediated JNK Activation Underlies Sleep Disturbance in an Alzheimer's Model.

PubMed

Song, Qian; Feng, Ge; Huang, Zehua; Chen, Xiaoman; Chen, Zhaohuan; Ping, Yong

2017-10-01

Impaired sleep patterns are common symptoms of Alzheimer's disease (AD). Cellular mechanisms underlying sleep disturbance in AD remain largely unknown. Here, using a Drosophila Aβ42 AD model, we show that Aβ42 markedly decreases sleep in a large population, which is accompanied with postdevelopmental axonal arborization of wake-promoting pigment-dispersing factor (PDF) neurons. The arborization is mediated in part via JNK activation and can be reversed by decreasing JNK signaling activity. Axonal arborization and impaired sleep are correlated in Aβ42 and JNK kinase hemipterous mutant flies. Image reconstruction revealed that these aberrant fibers preferentially project to pars intercerebralis (PI), a fly brain region analogous to the mammalian hypothalamus. Moreover, PDF signaling in PI neurons was found to modulate sleep/wake activities, suggesting that excessive release of PDF by these aberrant fibers may lead to the impaired sleep in Aβ42 flies. Finally, inhibition of JNK activation in Aβ42 flies restores nighttime sleep loss, decreases Aβ42 accumulation, and attenuates neurodegeneration. These data provide a new mechanism by which sleep disturbance could be induced by Aβ42 burden, a key initiator of a complex pathogenic cascade in AD.

On-the-fly reduction of open loops

NASA Astrophysics Data System (ADS)

Buccioni, Federico; Pozzorini, Stefano; Zoller, Max

2018-01-01

Building on the open-loop algorithm we introduce a new method for the automated construction of one-loop amplitudes and their reduction to scalar integrals. The key idea is that the factorisation of one-loop integrands in a product of loop segments makes it possible to perform various operations on-the-fly while constructing the integrand. Reducing the integrand on-the-fly, after each segment multiplication, the construction of loop diagrams and their reduction are unified in a single numerical recursion. In this way we entirely avoid objects with high tensor rank, thereby reducing the complexity of the calculations in a drastic way. Thanks to the on-the-fly approach, which is applied also to helicity summation and for the merging of different diagrams, the speed of the original open-loop algorithm can be further augmented in a very significant way. Moreover, addressing spurious singularities of the employed reduction identities by means of simple expansions in rank-two Gram determinants, we achieve a remarkably high level of numerical stability. These features of the new algorithm, which will be made publicly available in a forthcoming release of the OpenLoops program, are particularly attractive for NLO multi-leg and NNLO real-virtual calculations.

Wing-pitch modulation in maneuvering fruit flies is explained by an interplay between aerodynamics and a torsional spring

NASA Astrophysics Data System (ADS)

Beatus, Tsevi; Cohen, Itai

2015-11-01

While the wing kinematics of many flapping insects have been well characterized, understanding the underlying physiological mechanisms that determine these kinematics is still a challenge. Two of the main difficulties arise from the complexity of the interaction between a flapping wing and its own unsteady flow, as well as the intricate mechanics the insect wing-hinge, which is among the most complicated joints in the animal kingdom. These difficulties call for the application of reduced-order approaches. Here, we model the torques exerted by the wing-hinge along the wing-pitch axis of maneuvering fruit flies as a damped torsional spring with elastic and damping coefficients as well as a rest angle. Furthermore, we model the air flows using simplified quasi-static aerodynamics. Our findings suggest that flies take advantage of the passive coupling between aerodynamics and the damped torsional spring to indirectly control their wing-pitch kinematics by modulating the spring damping and elastic coefficients. These results, in conjunction with the previous literature, indicate flies can accurately control their wing-pitch kinematics on a sub-wing-beat time-scale by modulating all three effective spring parameters on longer time-scales.

Safe to Fly: Certifying COTS Hardware for Spaceflight

NASA Technical Reports Server (NTRS)

Fichuk, Jessica L.

2011-01-01

Providing hardware for the astronauts to use on board the Space Shuttle or International Space Station (ISS) involves a certification process that entails evaluating hardware safety, weighing risks, providing mitigation, and verifying requirements. Upon completion of this certification process, the hardware is deemed safe to fly. This process from start to finish can be completed as quickly as 1 week or can take several years in length depending on the complexity of the hardware and whether the item is a unique custom design. One area of cost and schedule savings that NASA implements is buying Commercial Off the Shelf (COTS) hardware and certifying it for human spaceflight as safe to fly. By utilizing commercial hardware, NASA saves time not having to develop, design and build the hardware from scratch, as well as a timesaving in the certification process. By utilizing COTS hardware, the current detailed certification process can be simplified which results in schedule savings. Cost savings is another important benefit of flying COTS hardware. Procuring COTS hardware for space use can be more economical than custom building the hardware. This paper will investigate the cost savings associated with certifying COTS hardware to NASA s standards rather than performing a custom build.

A set of alkali and alkaline-earth coordination polymers based on the ligand 2-(1H-benzotriazol-1-yl) acetic acid: Effects the radius of metal ions on structures and properties

NASA Astrophysics Data System (ADS)

Wang, Jin-Hua; Tang, Gui-Mei; Qin, Ting-Xiao; Yan, Shi-Chen; Wang, Yong-Tao; Cui, Yue-Zhi; Weng Ng, Seik

2014-11-01

Four new metal coordination complexes, namely, [Na(BTA)]n (1), [K2(BTA)2(μ2-H2O)]n (2), and [M(BTA)2(H2O)2]n (M=Ca(II) and Sr(II) for 3 and 4, respectively) [BTA=2-(1H-benzotriazol-1-yl) acetic anion], have been obtained under hydrothermal condition, by reacting the different alkali and alkaline-earth metal hydroxides with HBTA. Complexes 1-4 were structurally characterized by X-ray single-crystal diffraction, EA, IR, PXRD, and thermogravimetry analysis (TGA). These complexes display low-dimensional features displaying various two-dimensional (2D) and one-dimensional (1D) coordination motifs. Complex 1 displays a 2D layer with the thickness of 1.5 nm and possesses a topologic structure of a 11 nodal net with Schläfli symbol of {318}. Complex 2 also shows a thick 2D sheet and its topologic structure is a 9 nodes with Schläfli symbol of {311×42}. Complexes 3 and 4 possess a 1D linear chain and further stack via hydrogen bonding interactions to generate a three-dimensional supramolecular architecture. These results suggest that both the coordination preferences of the metal ions and the versatile nature of this flexible ligand play a critical role in the final structures. The luminescent spectra show strong emission intensities in complexes 1-4, which display violet photoluminescence. Additionally, ferroelectric, dielectric and nonlinear optic (NLO) second-harmonic generation (SHG) properties of 2 are discussed in detail.

Dicer is dispensable for asymmetric RISC loading in mammals

PubMed Central

Betancur, Juan G.; Tomari, Yukihide

2012-01-01

In flies, asymmetric loading of small RNA duplexes into Argonaute2-containing RNA-induced silencing complex (Ago2-RISC) requires Dicer-2/R2D2 heterodimer, which acts as a protein sensor for the thermodynamic stabilities of the ends of small RNA duplexes. However, the mechanism of small RNA asymmetry sensing in mammalian RISC assembly remains obscure. Here, we quantitatively examined RISC assembly and target silencing activity in the presence or absence of Dicer in mammals. Our data show that, unlike the well-characterized fly Ago2-RISC assembly pathway, mammalian Dicer is dispensable for asymmetric RISC loading in vivo and in vitro. PMID:22106413

Dicer is dispensable for asymmetric RISC loading in mammals.

PubMed

Betancur, Juan G; Tomari, Yukihide

2012-01-01

In flies, asymmetric loading of small RNA duplexes into Argonaute2-containing RNA-induced silencing complex (Ago2-RISC) requires Dicer-2/R2D2 heterodimer, which acts as a protein sensor for the thermodynamic stabilities of the ends of small RNA duplexes. However, the mechanism of small RNA asymmetry sensing in mammalian RISC assembly remains obscure. Here, we quantitatively examined RISC assembly and target silencing activity in the presence or absence of Dicer in mammals. Our data show that, unlike the well-characterized fly Ago2-RISC assembly pathway, mammalian Dicer is dispensable for asymmetric RISC loading in vivo and in vitro.

Of Fighting Flies, Mice, and Men: Are Some of the Molecular and Neuronal Mechanisms of Aggression Universal in the Animal Kingdom?

PubMed

Thomas, Amanda L; Davis, Shaun M; Dierick, Herman A

2015-08-01

Aggressive behavior is widespread in the animal kingdom, but the degree of molecular conservation between distantly related species is still unclear. Recent reports suggest that at least some of the molecular mechanisms underlying this complex behavior in flies show remarkable similarities with such mechanisms in mice and even humans. Surprisingly, some aspects of neuronal control of aggression also show remarkable similarity between these distantly related species. We will review these recent findings, address the evolutionary implications, and discuss the potential impact for our understanding of human diseases characterized by excessive aggression.

Of Fighting Flies, Mice, and Men: Are Some of the Molecular and Neuronal Mechanisms of Aggression Universal in the Animal Kingdom?

PubMed Central

Dierick, Herman A.

2015-01-01

Aggressive behavior is widespread in the animal kingdom, but the degree of molecular conservation between distantly related species is still unclear. Recent reports suggest that at least some of the molecular mechanisms underlying this complex behavior in flies show remarkable similarities with such mechanisms in mice and even humans. Surprisingly, some aspects of neuronal control of aggression also show remarkable similarity between these distantly related species. We will review these recent findings, address the evolutionary implications, and discuss the potential impact for our understanding of human diseases characterized by excessive aggression. PMID:26312756

The TreadWheel: Interval Training Protocol for Gently Induced Exercise in Drosophila melanogaster.

PubMed

Lowman, Kelsey E; Wyatt, Brélahn J; Cunneely, Owen P; Reed, Laura K

2018-06-08

The incidence of complex metabolic diseases has increased as a result of a widespread transition towards lifestyles of increased caloric intake and lowered activity levels. These multifactorial diseases arise from a combination of genetic, environmental, and behavioral factors. One such complex disease is Metabolic Syndrome (MetS), which is a cluster of metabolic disorders, including hypertension, hyperglycemia, and abdominal obesity. Exercise and dietary intervention are the primary treatments recommended by doctors to mitigate obesity and its subsequent metabolic diseases. Exercise intervention, in particular aerobic interval training, stimulates favorable changes in the common risk factors for Type 2 Diabetes Mellitus (T2DM), Cardiovascular Disease (CVD), and other conditions. With the influx of evidence describing the therapeutic effect exercise has on metabolic health, establishing a system that models exercise in a controlled setting provides a valuable tool for assessing the effects of exercise in an experimental context. Drosophila melanogaster is a great tool for investigating the physiological and molecular changes that result from exercise intervention. The flies have short lifespans and similar mechanisms of metabolizing nutrients when compared to humans. To induce exercise in Drosophila, we developed a machine called the TreadWheel, which utilizes the fly's innate, negative geotaxis tendency to gently induce climbing. This enables researchers to perform experiments on large cohorts of genetically diverse flies to better understand the genotype-by-environment interactions underlying the effects of exercise on metabolic health.

Detection of potential genetic hazards in complex environmental mixtures using plant cytogenetics and microbial mutagenesis assays. [Arsenic-contaminated groundwater and power plant fly ash extract

DOE Office of Scientific and Technical Information (OSTI.GOV)

Constantin, M J; Lowe, K; Rao, T K

1980-01-01

Solid wastes have been characterized to determine their potential hazards to humans and the environment. An arsenic-contaminated ground water sample increased the frequency of histidine revertants in Salmonella typhimurium (TA-98) at 0.025 to 5.000 ..mu..l per plate with Aroclor-induced S-9 liver microsomes. When 2.5 to 75 ..mu..l of the XAD-2 concentrate (12.5-fold, v:v) were used, the mutant frequency was increased in strains TA-98, TA-100, and TA-1537; metabolic activation was not required. Only the XAD-2 concentrate was mutagenic in the Saccharomyces cerevisiae haploid strain XL-7-10B; metabolic activation was not required. The mutagenic principal, which is not known, appears to be atmore » the limit of resolution; hence, the XAD-2 concentration is necessary to demonstrate mutagenic activity. The arsenic-contaminated ground water (0.0625 and 0.125 dilutions) and the power plant fly ash extract (undiluted) increased the frequency of bridges and fragements at anaphase in root tip cells of Hordeum. The fly ash sample was negative in the microbial assays. Results emphasize (1) the need for a battery of assays with different organisms and (2) the potential of a simple assay using plant root tip cells to detect mutagenic activity in complex environmental mixtures.« less

Cue-Induced Ethanol Seeking in Drosophila melanogaster Is Dose-Dependent

PubMed Central

Nunez, Kavin M.; Azanchi, Reza; Kaun, Karla R.

2018-01-01

Alcohol use disorder generates devastating social, medical and economic burdens, making it a major global health issue. The persistent nature of memories associated with intoxication experiences often induces cravings and triggers relapse in recovering individuals. Despite recent advances, the neural and molecular mechanisms underlying these memories are complex and not well understood. This makes finding effective pharmacological targets challenging. The investigation of persistent alcohol-associated memories in the fruit fly, Drosophila melanogaster, presents a unique opportunity to gain a comprehensive understanding of the memories for ethanol reward at the level of genes, molecules, neurons and circuits. Here we characterize the dose-dependent nature of ethanol on the expression of memory for an intoxication experience. We report that the concentration of ethanol, number of ethanol exposures, length of ethanol exposures, and timing between ethanol exposures are critical in determining whether ethanol is perceived as aversive or appetitive, and in how long the memory for the intoxicating properties of ethanol last. Our study highlights that fruit flies display both acute and persistent memories for ethanol-conditioned odor cues, and that a combination of parameters that determine the intoxication state of the fly influence the seemingly complex retention and expression of memories associated with intoxication. Our thorough behavioral characterization provides the opportunity to interrogate the biological underpinnings of these observed preference differences in future studies. PMID:29740347

How insect flight steering muscles work.

PubMed

Hedenström, Anders

2014-03-01

Insights into how exactly a fly powers and controls flight have been hindered by the need to unpick the dynamic complexity of the muscles involved. The wingbeats of insects are driven by two antagonistic groups of power muscles and the force is funneled to the wing via a very complex hinge mechanism. The hinge consists of several hardened and articulated cuticle elements called sclerites. This articulation is controlled by a great number of small steering muscles, whose function has been studied by means of kinematics and muscle activity. The details and partly novel function of some of these steering muscles and their tendons have now been revealed in research published in this issue of PLOS Biology. The new study from Graham Taylor and colleagues applies time-resolved X-ray microtomography to obtain a three-dimensional view of the blowfly wingbeat. Asymmetric power output is achieved by differential wingbeat amplitude on the left and right wing, which is mediated by muscular control of the hinge elements to mechanically block the wing stroke and by absorption of work by steering muscles on one of the sides. This new approach permits visualization of the motion of the thorax, wing muscles, and the hinge mechanism. This very promising line of work will help to reveal the complete picture of the flight motor of a fly. It also holds great potential for novel bio-inspired designs of fly-like micro air vehicles.

The black flies (Diptera: Simuliidae) of Vietnam.

PubMed

Takaoka, Hiroyuki; Sofian-Azirun, Mohd; Ya'cob, Zubaidah; Chen, Chee Dhang; Lau, Koon Weng; Low, VAN Lun; Pham, Xuan DA; Adler, Peter H

2017-05-05

The biodiversity of black flies (Diptera: Simuliidae), which are biting insects of medical and veterinary importance, is strikingly high in Southeast Asian countries, such as Indonesia, Malaysia, Philippines and Thailand. In 2013, we began to explore the fauna of black flies in Vietnam, which has so far been poorly studied. In this monograph, the wealth of the biodiversity of black flies in Vietnam is also confirmed on the basis of the results of our recent investigations, though limited to five provinces in the country.      Morphotaxonomic studies of black flies obtained from Sapa, Lao Cai Province, northern Vietnam, in 2014 and Nghe An Province, northern Vietnam, in 2015, and reexaminations of black flies collected from Tam Dao, Vinh Phuc Province, northern Vietnam, in 2013, Thua Thien Hue Province, central Vietnam, in 2014, and Lam Dong Province, southern Vietnam, in 2014, were conducted. A total of 22 species are described as new, including one in the newly recorded subgenus Montisimulium Rubtsov, and three species are recognized as new records from Vietnam. This investigation brings the number of species of black flies known in Vietnam to 70, all of which are assigned to the genus Simulium Latreille, and are placed in four subgenera (25 in Gomphostilbia Enderlein, one in Montisimulium, seven in Nevermannia Enderlein, and 37 in Simulium Latreille s. str.). The numbers of species-groups recognized include seven in Gomphostilbia, three in Nevermannia and nine in Simulium, indicating a high diversity of putative phylogenetic lineages. New species include S. (G.) sanchayense sp. nov. (= the species formerly regarded as S. (G.) brinchangense Takaoka, Sofian-Azirun & Hashim), S. (S.) lowi sp. nov. (= the species formerly regarded as S. (S.) brevipar Takaoka & Davies), S. (S.) fuscicoxae sp. nov. [= the species formerly regarded as S. (S.) rufibasis Brunetti (in part)], S. (S.) suoivangense sp. nov. [= morphoform 'b' of the S. (S.) tani Takaoka & Davies (complex)]. Newly recorded species are S. (G.) parahiyangum Takaoka & Sigit, S. (N.) maeaiense Takaoka & Srisuka, and S. (S.) doipuiense Takaoka & Choochote (complex) [= the species formerly regarded as S. (S.) rufibasis Brunetti (in part)]. The substitute name, S. (S.) huense, is given for the species that was described under the name of S. (S.) cavum from southern Vietnam. A redescription of the female, male, pupa and larva of S. (G.) asakoae Takaoka & Davies is presented, and the female and larva of S. (G.) hongthaii Takaoka, Sofian-Azirun & Ya'cob are described for the first time. Keys to 10 subgenera in the Oriental Region and all 70 species recorded from Vietnam are provided for females, males, pupae and mature larvae.      As investigations extend nationwide in all the provinces in Vietnam, more new species and records are expected to be discovered. It is hoped that this monograph will be useful as a baseline taxonomic reference for future studies of black flies in Vietnam and neighbouring countries.

Discriminatory Power and Reproducibility of Novel DNA Typing Methods for Mycobacterium tuberculosis Complex Strains

PubMed Central

Kremer, Kristin; Arnold, Catherine; Cataldi, Angel; Gutiérrez, M. Cristina; Haas, Walter H.; Panaiotov, Stefan; Skuce, Robin A.; Supply, Philip; van der Zanden, Adri G. M.; van Soolingen, Dick

2005-01-01

In recent years various novel DNA typing methods have been developed which are faster and easier to perform than the current internationally standardized IS6110 restriction fragment length polymorphism typing method. However, there has been no overview of the utility of these novel typing methods, and it is largely unknown how they compare to previously published methods. In this study, the discriminative power and reproducibility of nine recently described PCR-based typing methods for Mycobacterium tuberculosis were investigated using the strain collection of the interlaboratory study of Kremer et al. (J. Clin. Microbiol. 37:2607-2618, 1999). This strain collection contains 90 M. tuberculosis complex and 10 non-M. tuberculosis complex mycobacterial strains, as well as 31 duplicated DNA samples to assess reproducibility. The highest reproducibility was found with variable numbers of tandem repeat typing using mycobacterial interspersed repetitive units (MIRU VNTR) and fast ligation-mediated PCR (FLiP), followed by second-generation spoligotyping, ligation-mediated PCR (LM-PCR), VNTR typing using five repeat loci identified at the Queens University of Belfast (QUB VNTR), and the Amadio speciation PCR. Poor reproducibility was associated with fluorescent amplified fragment length polymorphism typing, which was performed in three different laboratories. The methods were ordered from highest discrimination to lowest by the Hunter-Gaston discriminative index as follows: QUB VNTR typing, MIRU VNTR typing, FLiP, LM-PCR, and spoligotyping. We conclude that both VNTR typing methods and FLiP typing are rapid, highly reliable, and discriminative epidemiological typing methods for M. tuberculosis and that VNTR typing is the epidemiological typing method of choice for the near future. PMID:16272496

Diversity patterns, Leishmania DNA detection, and bloodmeal identification of Phlebotominae sand flies in villages in northern Colombia

PubMed Central

León, Cielo; Paz, Andrea; López, Marla; Molina, Gisell; Toro, Diana; Ortiz, Mario; Cordovez, Juan Manuel; Atencia, María Claudia; Aguilera, Germán; Tovar, Catalina

2018-01-01

Leishmaniases are neglected tropical diseases exhibiting complex transmission cycles due to the number of parasite species circulating, sand fly species acting as vectors and infected mammals, including humans, which are defined in the New World as accidental hosts. However, current transmission scenarios are changing, and the disease is no longer exclusively related to forested areas but urban transmission foci occur, involving some species of domestic animals as suspected reservoirs. The aim of this study was to determine the transmission cycles in urban environments by evaluating sand fly diversity, detection of Leishmania DNA, and bloodmeal sources through intra and peridomestic collections. The study was carried out in Colombia, in 13 municipalities of Cordoba department, implementing a methodology that could be further used for the evaluation of vector-borne diseases in villages or towns. Our sampling design included 24 houses randomly selected in each of 15 villages distributed in 13 municipalities, which were sampled in two seasons in 2015 and 2016. Sand flies were collected using CDC light traps placed in intra and peridomestic habitats. In addition to the morphological identification, molecular identification through DNA barcodes was also performed. A total of 19,743 sand flies were collected and 13,848 of them (10,268 females and 3,580 males) were used in molecular procedures. Circulation of two known parasite species–Leishmania infantum and Leishmania panamensis was confirmed. Blood source analyses showed that sand flies fed on humans, particularly in the case of the known L. infantum vector, P. evansi; further analyses are advised to evaluate the reservoirs involved in parasite transmission. Our sampling design allowed us to evaluate potential transmission cycles on a department scale, by defining suspected vector species, parasite species present in different municipalities and feeding habits. PMID:29320544

Diversity patterns, Leishmania DNA detection, and bloodmeal identification of Phlebotominae sand flies in villages in northern Colombia.

PubMed

González, Camila; León, Cielo; Paz, Andrea; López, Marla; Molina, Gisell; Toro, Diana; Ortiz, Mario; Cordovez, Juan Manuel; Atencia, María Claudia; Aguilera, Germán; Tovar, Catalina

2018-01-01

Leishmaniases are neglected tropical diseases exhibiting complex transmission cycles due to the number of parasite species circulating, sand fly species acting as vectors and infected mammals, including humans, which are defined in the New World as accidental hosts. However, current transmission scenarios are changing, and the disease is no longer exclusively related to forested areas but urban transmission foci occur, involving some species of domestic animals as suspected reservoirs. The aim of this study was to determine the transmission cycles in urban environments by evaluating sand fly diversity, detection of Leishmania DNA, and bloodmeal sources through intra and peridomestic collections. The study was carried out in Colombia, in 13 municipalities of Cordoba department, implementing a methodology that could be further used for the evaluation of vector-borne diseases in villages or towns. Our sampling design included 24 houses randomly selected in each of 15 villages distributed in 13 municipalities, which were sampled in two seasons in 2015 and 2016. Sand flies were collected using CDC light traps placed in intra and peridomestic habitats. In addition to the morphological identification, molecular identification through DNA barcodes was also performed. A total of 19,743 sand flies were collected and 13,848 of them (10,268 females and 3,580 males) were used in molecular procedures. Circulation of two known parasite species-Leishmania infantum and Leishmania panamensis was confirmed. Blood source analyses showed that sand flies fed on humans, particularly in the case of the known L. infantum vector, P. evansi; further analyses are advised to evaluate the reservoirs involved in parasite transmission. Our sampling design allowed us to evaluate potential transmission cycles on a department scale, by defining suspected vector species, parasite species present in different municipalities and feeding habits.

Impact of introduction of Bactrocera dorsalis (Diptera: Tephritidae) and classical biological control releases of Fopius arisanus (Hymenoptera: Braconidae) on economically important fruit flies in French Polynesia.

PubMed

Vargas, Roger I; Leblanc, Luc; Putoa, Rudolph; Eitam, Avi

2007-06-01

Oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), was discovered on Tahiti Island in July 1996. Eradication programs were conducted from 1997 to 2001, but failed. From 1998 to 2006, B. dorsalis was recovered from 29 different host fruit from the five Society Islands: Tahiti, Moorea, Raiatea, Tahaa, and Huahine. Analysis of coinfestation patterns by B. dorsalis, Bactrocera tryoni (Froggatt), and Bactrocera kirki (Froggatt) suggested B. dorsalis had displaced these two species and become the most abundant fruit fly in coastal areas. To suppress B. dorsalis populations, a classical biological control program was initiated to introduce the natural enemy Fopius arisanus (Sonan) (Hymenoptera: Braconidae) into French Polynesia from Hawaii. Wasps were released and established on Tahiti, Moorea, Raiatea, Tahaa, and Huahine Islands. In guava, Psidium guajava L., collections for Tahiti, F. arisanus parasitism of fruit flies was 2.1, 31.8, 37.5, and 51.9% for fruit collected for 2003, 2004, 2005 and 2006, respectively. Based on guava collections in 2002 (before releases) and 2006 (after releases), there was a subsequent decrease in numbers of B. dorsalis, B. tryoni, and B. kirki fruit flies emerging (per kilogram of fruit) by 75.6, 79.3, and 97.9%, respectively. These increases in F. arisanus parasitism and decreases in infestation were similar for other host fruit. Establishment of F. arisanus is the most successful example of classical biological control of fruit flies in the Pacific area outside of Hawaii and serves as a model for introduction into South America, Africa, and China where species of the B. dorsalis complex are established.

Modeling the Temperature- and Age-Dependent Survival, Development, and Oviposition Rates of Stable Flies (Stomoxys calcitrans) (Diptera: Muscidae).

PubMed

Skovgård, Henrik; Nachman, Gösta

2017-10-01

Stable flies (Stomoxys calcitrans (L.)) can be a serious pest associated with cattle facilities. In Denmark, they occur most abundantly at organic farms, where they cannot be controlled by means of insecticides. On traditional farms, where chemical control is widely used, development of resistance is of increasing concern. Therefore, interest in biological control or other alternative methods has been growing during the recent years. In order to understand the complex relationships between a pest and its natural enemies in a variable environment, it is necessary to know how temperature affects the dynamics of the involved species. In this paper, we apply data derived from several existing sources to investigate the influence of temperature on development and survival of eggs, larvae, pupae, and adult stable flies, as well as on the fecundity of adult females. We demonstrate that the same modeling framework (called SANDY), previously applied to lifetable data of the pteromalid pupal parasitoid (Spalangia cameroni Perkins), a biological control agent used against stable flies, can also be used to model S. calcitrans. However, the predicted temperature responses depend on the data sources used to parameterize the model, which is reflected by differences in estimated population growth rates obtained from American and non-American studies. Elasticity analysis shows that growth rates are more sensitive to changes in viability, in particular of adult flies, than in fecundity, which may have implications for the management of stable fly populations. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Construction and evaluation of the immune protection of a recombinant divalent protein composed of the MrpA from MR/P fimbriae and flagellin of Proteus mirabilis strain against urinary tract infection.

PubMed

Habibi, Mehri; Asadi Karam, Mohammad Reza; Bouzari, Saeid

2018-04-01

Urinary tract infections (UTI) caused by Proteus mirabilis are prevalent among the catheterized patients. There is no effective vaccine to reduce the frequency of UTIs caused by P. mirabilis. In the present study, the immune responses and effectiveness of different combinations of MrpA and flagellin (FliC) of P. mirabilis were assessed intranasally in the mice model. The addition of FliC as adjuvant to MrpA in fusion form significantly raised the mucosal IgA and cellular (IFN-γ and IL-17) responses and maintained the serum IgG responses for 180 days after the first vaccination. Furthermore, MrpA in fusion form with FliC significantly increased the systemic, mucosal and IFN-γ responses of the FliC alone. In a bladder challenge assay with P. mirabilis, the fusion MrpA.FliC and the mixture of MrpA and FliC significantly decreased the colony count of the bacteria in the bladder and kidneys of mice in comparison to the control mice. It suggests a complex of the systemic, mucosal and cellular responses are needed for protection of the bladder and kidneys against P. mirabilis UTI. In our knowledge, the adjuvant property of the recombinant P. mirabilis flagellin was evaluated for the first time in a vaccine combination administered by an intranasal route. Our results suggest the recombinant flagellin of P. mirabilis could be used as an intranasal adjuvant in combination with other potential antigens against UTIs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Odorant binding protein 69a connects social interaction to modulation of social responsiveness in Drosophila.

PubMed

Bentzur, Assa; Shmueli, Anat; Omesi, Liora; Ryvkin, Julia; Knapp, Jon-Michael; Parnas, Moshe; Davis, Fred P; Shohat-Ophir, Galit

2018-04-01

Living in a social environment requires the ability to respond to specific social stimuli and to incorporate information obtained from prior interactions into future ones. One of the mechanisms that facilitates social interaction is pheromone-based communication. In Drosophila melanogaster, the male-specific pheromone cis-vaccenyl acetate (cVA) elicits different responses in male and female flies, and functions to modulate behavior in a context and experience-dependent manner. Although it is the most studied pheromone in flies, the mechanisms that determine the complexity of the response, its intensity and final output with respect to social context, sex and prior interaction, are still not well understood. Here we explored the functional link between social interaction and pheromone-based communication and discovered an odorant binding protein that links social interaction to sex specific changes in cVA related responses. Odorant binding protein 69a (Obp69a) is expressed in auxiliary cells and secreted into the olfactory sensilla. Its expression is inversely regulated in male and female flies by social interactions: cVA exposure reduces its levels in male flies and increases its levels in female flies. Increasing or decreasing Obp69a levels by genetic means establishes a functional link between Obp69a levels and the extent of male aggression and female receptivity. We show that activation of cVA-sensing neurons is sufficeint to regulate Obp69a levels in the absence of cVA, and requires active neurotransmission between the sensory neuron to the second order olfactory neuron. The cross-talk between sensory neurons and non-neuronal auxiliary cells at the olfactory sensilla, represents an additional component in the machinery that promotes behavioral plasticity to the same sensory stimuli in male and female flies.

High-speed laser microsurgery of alert fruit flies for fluorescence imaging of neural activity

PubMed Central

Sinha, Supriyo; Liang, Liang; Ho, Eric T. W.; Urbanek, Karel E.; Luo, Liqun; Baer, Thomas M.; Schnitzer, Mark J.

2013-01-01

Intravital microscopy is a key means of monitoring cellular function in live organisms, but surgical preparation of a live animal for microscopy often is time-consuming, requires considerable skill, and limits experimental throughput. Here we introduce a spatially precise (<1-µm edge precision), high-speed (<1 s), largely automated, and economical protocol for microsurgical preparation of live animals for optical imaging. Using a 193-nm pulsed excimer laser and the fruit fly as a model, we created observation windows (12- to 350-µm diameters) in the exoskeleton. Through these windows we used two-photon microscopy to image odor-evoked Ca2+ signaling in projection neuron dendrites of the antennal lobe and Kenyon cells of the mushroom body. The impact of a laser-cut window on fly health appears to be substantially less than that of conventional manual dissection, for our imaging durations of up to 18 h were ∼5–20 times longer than prior in vivo microscopy studies of hand-dissected flies. This improvement will facilitate studies of numerous questions in neuroscience, such as those regarding neuronal plasticity or learning and memory. As a control, we used phototaxis as an exemplary complex behavior in flies and found that laser microsurgery is sufficiently gentle to leave it intact. To demonstrate that our techniques are applicable to other species, we created microsurgical openings in nematodes, ants, and the mouse cranium. In conjunction with emerging robotic methods for handling and mounting flies or other small organisms, our rapid, precisely controllable, and highly repeatable microsurgical techniques should enable automated, high-throughput preparation of live animals for optical experimentation. PMID:24167298

Interlaboratory comparison of mutagenesis testing of coal fly ash derived from differenct coal conversion technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chrisp, C.; Hobbs, C.; Clark, R.

1979-01-01

This experiment showed that mutagenicity of fly ash derived from different coal conversion technologies, as determined by the Ames plate incorporation test, was similar in all three laboratories. The differences in mutagenic activity of each fly ash between laboratories with different solvent extraction methods were no greater than one order of magnitude. In addition, there were much smaller, but still significant differences in mutagenic activity between laboratories when the same solvent extract of a particular fly ash was tested in each laboratory. There were also significant differences in mutagenicity of the positive control mutagen (maximum of fivefold) between laboratories. Becausemore » of this difference in Ames test sensitivity between laboratories, the influence of the solvent extraction methods on differences in mutagenicity was not clear. However, the data suggested that either there were significant differences in the degree of sensitivity of Ames tests for different complex mixtures within each laboratory, or else there were differences in mutagen extraction efficiency between different solvent extraction methods. Both Ames test sensitivity and solvent extraction may be important. Further work would be necessary to separate the contribution of these two factors. An important aspect of further work would be to separate the contribution of the innate sensitivity of substrains of Ames tester strains in each laboratory from the possible effects of differences in Ames testing methodology. This could be done by testing the same extracts of fly ash and positive control mutagens with substrains of tester strains exchanged between laboratories. This work also implies that caution should be exercised in assuming that the same solvent would have the same efficiency for extraction of mutagens from different fly ashes even within the same laboratory.« less

Drosophila social clustering is disrupted by anesthetics and in narrow abdomen ion channel mutants.

PubMed

Burg, E D; Langan, S T; Nash, H A

2013-04-01

Members of many species tend to congregate, a behavioral strategy known as local enhancement. Selective advantages of local enhancement range from efficient use of resources to defense from predators. While previous studies have examined many types of social behavior in fruit flies, few have specifically investigated local enhancement. Resource-independent local enhancement (RILE) has recently been described in the fruit fly using a measure called social space index (SSI), although the neural mechanisms remain unknown. Here, we analyze RILE of Drosophila under conditions that allow us to elucidate its neural mechanisms. We have investigated the effects of general volatile anesthetics, compounds that compromise higher order functioning of the type typically required for responding to social cues. We exposed Canton-S flies to non-immobilizing concentrations of halothane and found that flies had a significantly decreased SSI compared with flies tested in air. Narrow abdomen (na) mutants, which display altered responses to anesthetics in numerous behavioral assays, also have a significantly reduced SSI, an effect that was fully reversed by restoring expression of na by driving a UAS-NA rescue construct with NA-GAL4. We found that na expression in cholinergic neurons fully rescued the behavioral defect, whereas expression of na in glutamatergic neurons did so only partially. Our results also suggest a role for na expression in the mushroom bodies (MBs), as suppressing na expression in the MBs of NA-GAL4 rescue flies diminishes SSI. Our data indicate that RILE, a simple behavioral strategy, requires complex neural processing. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

KENNEDY SPACE CENTER, FLA. -- Family members of the STS-107 astronauts and other dignitaries watch NASA T-38 jets fly over the Space Mirror Memorial at the Kennedy Space Center Visitor Complex in a Missing Man Formation. During this dedication ceremony, the names of the STS-107 astronauts who lost their lives during the Columbia accident -- Rick Husband, Willie McCool, Laurel Clark, Michael Anderson, David Brown, Kalpana Chawla, and Ilan Ramon -- join the names of 17 other space heroes who gave their lives for the U.S. space program.

NASA Image and Video Library

2003-10-28

KENNEDY SPACE CENTER, FLA. -- Family members of the STS-107 astronauts and other dignitaries watch NASA T-38 jets fly over the Space Mirror Memorial at the Kennedy Space Center Visitor Complex in a Missing Man Formation. During this dedication ceremony, the names of the STS-107 astronauts who lost their lives during the Columbia accident -- Rick Husband, Willie McCool, Laurel Clark, Michael Anderson, David Brown, Kalpana Chawla, and Ilan Ramon -- join the names of 17 other space heroes who gave their lives for the U.S. space program.

A Conserved Developmental Mechanism Builds Complex Visual Systems in Insects and Vertebrates

PubMed Central

Joly, Jean-Stéphane; Recher, Gaelle; Brombin, Alessandro; Ngo, Kathy; Hartenstein, Volker

2016-01-01

The visual systems of vertebrates and many other bilaterian clades consist of complex neural structures guiding a wide spectrum of behaviors. Homologies at the level of cell types and even discrete neural circuits have been proposed, but many questions of how the architecture of visual neuropils evolved among different phyla remain open. In this review we argue that the profound conservation of genetic and developmental steps generating the eye and its target neuropils in fish and fruit flies supports a homology between some core elements of bilaterian visual circuitries. Fish retina and tectum, and fly optic lobe, develop from a partitioned, unidirectionally proliferating neurectodermal domain that combines slowly dividing neuroepithelial stem cells and rapidly amplifying progenitors with shared genetic signatures to generate large numbers and different types of neurons in a temporally ordered way. This peculiar ‘conveyor belt neurogenesis’ could play an essential role in generating the topographically ordered circuitry of the visual system. PMID:27780043

Effect of temperature on the development and survival of immature stages of the carambola fruit fly, Bactrocera carambolae, and the Asian papaya fruit fly, Bactrocera papayae, reared on guava diet

PubMed Central

Danjuma, Solomon; Thaochan, Narit; Permkam, Surakrai; Satasook, Chutamas

2014-01-01

Abstract Members of the Bactrocera dorsalis Hendel (Diptera: Tephritidae) complex constitute well-recognized destructive pests of fruits in peninsular Thailand. The development and survival of immature stages of the carambola fruit fly, Bactrocera carambolae Drew & Hancock, and the Asian papaya fruit fly, Bactrocera papayae Drew & Hancock , were compared at six constant temperatures of 15, 20, 25, 27, 30, and 35°C, 70 ± 5% relative humidity, and a photoperiod of 12:12 (L:D). The objectives were to determine the effect of temperature on the developmental stages for optimizing rearing and to understand the geographical pattern of occurrence of these fruit fly species. A strong and positive linear relationship was observed between temperature and developmental rate of immature stages of B. carambolae. Similarly, a strong and positive linear relationship was observed between temperature and developmental rate of B. papayae. A temperature summation model was used to estimate the lower threshold temperature and the thermal constant. Bactrocera papayae was significantly faster in development and higher in survival and appeared to be better adapted to low temperatures than B. carambolae, as it exhibited the lowest threshold temperatures at all immature stages. The observed differences in response to various temperatures revealed to some extent the impact of temperature on these species’ distribution in peninsular Thailand and other parts of the world. PMID:25368070

A Sensory-Motor Control Model of Animal Flight Explains Why Bats Fly Differently in Light Versus Dark

PubMed Central

Bar, Nadav S.; Skogestad, Sigurd; Marçal, Jose M.; Ulanovsky, Nachum; Yovel, Yossi

2015-01-01

Animal flight requires fine motor control. However, it is unknown how flying animals rapidly transform noisy sensory information into adequate motor commands. Here we developed a sensorimotor control model that explains vertebrate flight guidance with high fidelity. This simple model accurately reconstructed complex trajectories of bats flying in the dark. The model implies that in order to apply appropriate motor commands, bats have to estimate not only the angle-to-target, as was previously assumed, but also the angular velocity (“proportional-derivative” controller). Next, we conducted experiments in which bats flew in light conditions. When using vision, bats altered their movements, reducing the flight curvature. This change was explained by the model via reduction in sensory noise under vision versus pure echolocation. These results imply a surprising link between sensory noise and movement dynamics. We propose that this sensory-motor link is fundamental to motion control in rapidly moving animals under different sensory conditions, on land, sea, or air. PMID:25629809

Monte Carlo Simulations of the Formation Flying Dynamics for the Magnetospheric Multiscale (MMS) Mission

NASA Technical Reports Server (NTRS)

Schiff, Conrad; Dove, Edwin

2011-01-01

The MMS mission is an ambitious space physics mission that will fly 4 spacecraft in a tetrahedron formation in a series of highly elliptical orbits in order to study magnetic reconnection in the Earth's magnetosphere. The mission design is comprised of a combination of deterministic orbit adjust and random maintenance maneuvers distributed over the 2.5 year mission life. Formal verification of the requirements is achieved by analysis through the use of the End-to-End (ETE) code, which is a modular simulation of the maneuver operations over the entire mission duration. Error models for navigation accuracy (knowledge) and maneuver execution (control) are incorporated to realistically simulate the possible maneuver scenarios that might be realized These error models, coupled with the complex formation flying physics, lead to non-trivial effects that must be taken into account by the ETE automation. Using the ETE code, the MMS Flight Dynamics team was able to demonstrate that the current mission design satisfies the mission requirements.

Island phytophagy: explaining the remarkable diversity of plant-feeding insects

PubMed Central

Joy, Jeffrey B.; Crespi, Bernard J.

2012-01-01

Plant-feeding insects have undergone unparalleled diversification among different plant taxa, yet explanations for variation in their diversity lack a quantitative, predictive framework. Island biogeographic theory has been applied to spatially discrete habitats but not to habitats, such as host plants, separated by genetic distance. We show that relationships between the diversity of gall-inducing flies and their host plants meet several fundamental predictions from island biogeographic theory. First, plant-taxon genetic distinctiveness, an integrator for long-term evolutionary history of plant lineages, is a significant predictor of variance in the diversity of gall-inducing flies among host-plant taxa. Second, range size and structural complexity also explain significant proportions of the variance in diversity of gall-inducing flies among different host-plant taxa. Third, as with other island systems, plant-lineage age does not predict species diversity. Island biogeographic theory, applied to habitats defined by genetic distance, provides a novel, comprehensive framework for analysing and explaining the diversity of plant-feeding insects and other host-specific taxa. PMID:22553094

Island phytophagy: explaining the remarkable diversity of plant-feeding insects.

PubMed

Joy, Jeffrey B; Crespi, Bernard J

2012-08-22

Plant-feeding insects have undergone unparalleled diversification among different plant taxa, yet explanations for variation in their diversity lack a quantitative, predictive framework. Island biogeographic theory has been applied to spatially discrete habitats but not to habitats, such as host plants, separated by genetic distance. We show that relationships between the diversity of gall-inducing flies and their host plants meet several fundamental predictions from island biogeographic theory. First, plant-taxon genetic distinctiveness, an integrator for long-term evolutionary history of plant lineages, is a significant predictor of variance in the diversity of gall-inducing flies among host-plant taxa. Second, range size and structural complexity also explain significant proportions of the variance in diversity of gall-inducing flies among different host-plant taxa. Third, as with other island systems, plant-lineage age does not predict species diversity. Island biogeographic theory, applied to habitats defined by genetic distance, provides a novel, comprehensive framework for analysing and explaining the diversity of plant-feeding insects and other host-specific taxa.

Tsetse Salivary Gland Proteins 1 and 2 Are High Affinity Nucleic Acid Binding Proteins with Residual Nuclease Activity

PubMed Central

Caljon, Guy; Ridder, Karin De; Stijlemans, Benoît; Coosemans, Marc; Magez, Stefan; De Baetselier, Patrick; Van Den Abbeele, Jan

2012-01-01

Analysis of the tsetse fly salivary gland EST database revealed the presence of a highly enriched cluster of putative endonuclease genes, including tsal1 and tsal2. Tsal proteins are the major components of tsetse fly (G. morsitans morsitans) saliva where they are present as monomers as well as high molecular weight complexes with other saliva proteins. We demonstrate that the recombinant tsetse salivary gland proteins 1&2 (Tsal1&2) display DNA/RNA non-specific, high affinity nucleic acid binding with KD values in the low nanomolar range and a non-exclusive preference for duplex. These Tsal proteins exert only a residual nuclease activity with a preference for dsDNA in a broad pH range. Knockdown of Tsal expression by in vivo RNA interference in the tsetse fly revealed a partially impaired blood digestion phenotype as evidenced by higher gut nucleic acid, hematin and protein contents. PMID:23110062

Wood Usage and Fire Veneration in the Pamir, Xinjiang, 2500 yr BP.

PubMed

Shen, Hui; Wu, Xinhua; Tang, Zihua; Zhou, Xinying; Sun, Nan; Li, Xiaoqiang

2015-01-01

Located on the Pamir Plateau in Xinjiang Province, China, the Ji'erzankale Necropolis dates back to 2500 yr BP. Many materials that have been unearthed in this cemetery, including shoo konghou (musical instrument), bronze mirrors and glass beads, suggest cultural transference between East and West. Furthermore, small-sized and rounded fire altars made from sweet-scented Sabina were found for the first time and regarded as implements for fire veneration. We identified 70 wooden objects from 25 tombs within the Necropolis, and found that each object had been made from one of seven tree species. Analysis revealed that the inhabitants of the region mainly used the most widely available types of wood, namely Betula and Populus. People also specifically chose inflammable Populus wood to make hearth boards and hand drills (both are used for making fire by drilling), rigid Betula wood to craft wooden plates. Salix was used for fashioning wooden sticks, while sweet-scented Sabina was the preferred choice for making fire altars. Lonicera was selected for arrow shaft manufacture and Fraxinus syriaca, which has a beautiful grain, was chosen for making musical instruments. Conscious selection of different types of wood indicates that people of the Pamir Plateau were aware of the properties of various types of timbers, and were able to exploit these properties to the full. In turn, this demonstrates their wisdom and their ability to survive in, and adapt to, their local environment.

Individual differences in children's pronoun processing during reading: Detection of incongruence is associated with higher reading fluency and more regressions.

PubMed

Eilers, Sarah; Tiffin-Richards, Simon P; Schroeder, Sascha

2018-05-10

In two eye tracking experiments, we tested fourth graders' and adults' sensitivity to gender feature mismatches during reading of pronouns and their susceptibility to interference of feature-matching entities in the sentence. In Experiment 1, we showed children and adults two-phrase sentences such as "Leon{m}/Lisa{f} shooed away the sparrow{m}/the seagull{f} and then he{m} ate the tasty sandwich." Eye tracking measures showed no qualitative differences between children's and adults' processing of the pronouns. Both age groups showed longer gaze durations on subject mismatching than on matching pronouns, and there was no evidence of interference of a gender-matching object. Strikingly, in contrast to the adults, not all fourth graders reported detection of the subject gender mismatch. In Experiment 2, we replicated earlier results with a larger sample of children (N = 75) and found that only half of the fourth graders detected the gender mismatch during reading. The detectors' reading pattern at the pronoun differed from that of the non-detectors. Children who reported detection of the mismatch showed a reading pattern more similar to the adults. Children who did not report detection of the mismatch had comparably slower gaze durations and were less likely to make regressions directly at the pronoun. We conclude that children who read more fluently use their available processing resources to immediately repair grammatical inconsistencies encountered in a text. Copyright © 2018 Elsevier Inc. All rights reserved.

Wood Usage and Fire Veneration in the Pamir, Xinjiang, 2500 yr BP

PubMed Central

Shen, Hui; Wu, Xinhua; Tang, Zihua; Zhou, Xinying; Sun, Nan; Li, Xiaoqiang

2015-01-01

Located on the Pamir Plateau in Xinjiang Province, China, the Ji’erzankale Necropolis dates back to 2500 yr BP. Many materials that have been unearthed in this cemetery, including shoo konghou (musical instrument), bronze mirrors and glass beads, suggest cultural transference between East and West. Furthermore, small-sized and rounded fire altars made from sweet-scented Sabina were found for the first time and regarded as implements for fire veneration. We identified 70 wooden objects from 25 tombs within the Necropolis, and found that each object had been made from one of seven tree species. Analysis revealed that the inhabitants of the region mainly used the most widely available types of wood, namely Betula and Populus. People also specifically chose inflammable Populus wood to make hearth boards and hand drills (both are used for making fire by drilling), rigid Betula wood to craft wooden plates. Salix was used for fashioning wooden sticks, while sweet-scented Sabina was the preferred choice for making fire altars. Lonicera was selected for arrow shaft manufacture and Fraxinus syriaca, which has a beautiful grain, was chosen for making musical instruments. Conscious selection of different types of wood indicates that people of the Pamir Plateau were aware of the properties of various types of timbers, and were able to exploit these properties to the full. In turn, this demonstrates their wisdom and their ability to survive in, and adapt to, their local environment. PMID:26308646

There is no magic fruit fly trap: multiple biological factors influence the response of adult Anastrepha ludens and Anastrepha obliqua (Diptera: Tephritidae) individuals to MultiLure traps baited with BioLure or NuLure.

PubMed

Díaz-Fleischer, Francisco; Arredondo, José; Flores, Salvador; Montoya, Pablo; Aluja, Martín

2009-02-01

Field-cage experiments were performed to determine the effectiveness of MultiLure traps (Better World MFG Inc., Fresno, CA) baited with NuLure (Miller Chemical and Fertilizer Corp., Hanover, PA) or BioLure (Suterra LLC, Inc., Bend, OR) in capturing individually marked Mexican fruit fly, Anastrepha ludens (Loew), and West Indian fruit fly, Anastrepha obliqua (Macquart) (Diptera: Tephritidae), of both sexes. Experimental treatments involved wild and laboratory-reared flies of varying ages (2-4 and 15-18 d) and dietary histories (sugar only, open fruit, open fruit plus chicken feces, and hydrolyzed protein mixed with sugar). Data were divided into two parts: total captures over a 24-h period and trap visits/landings, entrances into interior of trap ,and effective captures (i.e., drowning in liquid bait or water) over a 5-h detailed observation period (0600-1100 hours). The response to the two baits varied by fly species, gender, physiological state, age, and strain. Importantly, there were several highly significant interactions among these factors, underlining the complex nature of the response. The two baits differed in attractiveness for A. obliqua but not A. ludens. The effect of strain (wild versus laboratory flies) was significant for A. ludens but not A. obliqua. For effect of dietary history, adults of both species, irrespective of sex, were significantly less responsive to both baits when fed on a mixture of protein and sugar when compared with adults fed the other diets. Finally, we confirmed previous observations indicating that McPhail-type traps are quite inefficient. Considering the total 24-h fly tenure in the cage, and independent of bait treatment and fly type (i.e., strain, adult diet, gender and age), of a total of 2,880 A. obliqua and 2,880 A. ludens adults released into the field cages over the entire study (15 replicates), only 564 (19.6%) and 174 (6%) individuals, respectively, were effectively caught. When only considering the 5-h detailed observation period and independent of bait treatment and fly type, of a total of 785 marked flies that landed on traps (519 females and 266 males, respectively), only 10.3% (144 females and 59 males) and 20.8% (25 females and 18 males) A. obliqua and A. ludens individuals, respectively, ended up being effectively captured. We discuss the practical implications of these findings with respect to developing new baits and designing new traps and to the interpretation of capture results in the field.

Air force Thunderbirds flying above the Kennedy Space Center

NASA Image and Video Library

2007-02-01

Look -- It's a bird and a plane! A U.S. Air Force Thunderbird F-16D aircraft streaks through the sky past a slower-flying stork over the NASA News Center. The pilot is Maj. Tad Clark, who, after landing at the Shuttle Landing Facility, announced that Kennedy Space Center Visitor Complex will host the inaugural World Space Expo from Nov. 3 to 11, featuring an aerial salute by the Thunderbirds on its opening weekend. The Expo will create one of the largest displays of space artifacts, hardware and personalities ever assembled in one location with the objective to inspire, educate and engage the public by highlighting the achievements and benefits of space exploration.

Earth Observation

NASA Image and Video Library

2014-07-19

ISS040-E-070424 (19 July 2014) --- One of the Expedition 40 crew members aboard the Earth-orbiting International Space Station recorded this July 19 image of wildfires which are plaguing the Northwest and causing widespread destruction. The orbital outpost was flying 223 nautical miles above Earth at the time of the photo. Lightning has been given as the cause of the Ochoco Complex fires in the Ochoco National Forest in central Oregon. The complex has gotten larger since this photo was taken.

Neuronal control of locomotor handedness in Drosophila.

PubMed

Buchanan, Sean M; Kain, Jamey S; de Bivort, Benjamin L

2015-05-26

Genetically identical individuals display variability in their physiology, morphology, and behaviors, even when reared in essentially identical environments, but there is little mechanistic understanding of the basis of such variation. Here, we investigated whether Drosophila melanogaster displays individual-to-individual variation in locomotor behaviors. We developed a new high-throughout platform capable of measuring the exploratory behavior of hundreds of individual flies simultaneously. With this approach, we find that, during exploratory walking, individual flies exhibit significant bias in their left vs. right locomotor choices, with some flies being strongly left biased or right biased. This idiosyncrasy was present in all genotypes examined, including wild-derived populations and inbred isogenic laboratory strains. The biases of individual flies persist for their lifetime and are nonheritable: i.e., mating two left-biased individuals does not yield left-biased progeny. This locomotor handedness is uncorrelated with other asymmetries, such as the handedness of gut twisting, leg-length asymmetry, and wing-folding preference. Using transgenics and mutants, we find that the magnitude of locomotor handedness is under the control of columnar neurons within the central complex, a brain region implicated in motor planning and execution. When these neurons are silenced, exploratory laterality increases, with more extreme leftiness and rightiness. This observation intriguingly implies that the brain may be able to dynamically regulate behavioral individuality.

Trypanosoma avium of raptors (Falconiformes): phylogeny and identification of vectors.

PubMed

Votýpka, J; Oborník, M; Volf, P; Svobodová, M; Lukes, J

2002-09-01

Avian trypanosomes are widespread parasites of birds, the transmission of which remains mostly unclear, with various blood-sucking insects mentioned as possible vectors. A search for vectors of trypanosomes of sparrowhawk (Accipiter nisus), buzzard (Buteo buteo), lesser-spotted eagle (Aquila pomarina) and kestrel (Falco tinnunculus) was performed in Czech and Slovak Republics. Black flies (Eusimulium spp.), hippoboscid flies (Ornithomyia avicularia), mosquitoes (Culex pipiens pipiens) and biting midges (Culicoides spp.), trapped while attempting to feed on raptor nestlings, were found to contain trypanosomatids in their intestine. Trypanosomes from the raptors and blood-sucking insects were isolated, and their 18S rRNA sequences were used for species identification and for the inference of intra- and interspecific relationships. Together with the trypanosome isolated from a black fly, the bird trypanosomes formed a well-supported Trypanosoma avium clade. The isolates derived from hippoboscid flies and mosquitoes are most likely also avian trypanosomes infecting birds other than the studied raptors. Analysis of the kinetoplast, that has features characteristic for the avian trypanosomes (minicircle size; dimensions of the kinetoplast disc), provided further evidence for the identification of vectors. It is suggested that all trypanosomes isolated from raptors included in this study belong to the T. avium complex and are transmitted by the ornithophilic simuliids such as Eusimulium securiforme.

Sex differences in metabolic rates in field crickets and their dipteran parasitoids.

PubMed

Kolluru, G R; Chappell, M A; Zuk, M

2004-11-01

Sex differences in metabolic rate (MR) can result from dimorphism in the performance of energetically demanding activities. Male crickets (Teleogryllus oceanicus) engage in costly calling and aggressive activity not performed by females. Consistent with this difference, we found higher maximal MR, factorial scope, and fat content in males than females. T. oceanicus song is also costly because it attracts the parasitoid fly Ormia ochracea. Parasitized crickets had reduced maximal MR consistent with a metabolic cost to harboring larvae. This cost was greater for females, either because females invest more heavily into reproduction at the expense of metabolic capacity, or because males are under stronger selection to respond to infection. Little is known about O. ochracea outside of its auditory system and parasitic lifestyle. We observed greater resting MR in male flies, possibly reflecting a sex difference in the requirement for metabolic power output, because male flies perform potentially costly mating behavior not seen in females. We found a positive relationship between larval density within a cricket and pupal resting MR, suggesting that crickets in good condition are able to both harbor more larvae and produce larvae with higher resting MR. These results reveal a complex interplay between the metabolism of crickets and their fly parasitoids.

Fly ash particles spheroidization using low temperature plasma energy

NASA Astrophysics Data System (ADS)

Shekhovtsov, V. V.; Volokitin, O. G.; Kondratyuk, A. A.; Vitske, R. E.

2016-11-01

The paper presents the investigations on producing spherical particles 65-110 μm in size using the energy of low temperature plasma (LTP). These particles are based on flow ash produced by the thermal power plant in Seversk, Tomsk region, Russia. The obtained spherical particles have no defects and are characterized by a smooth exterior surface. The test bench is designed to produce these particles. With due regard for plasma temperature field distribution, it is shown that the transition of fly ash particles to a state of viscous flow occurs at 20 mm distance from the plasma jet. The X-ray phase analysis is carried out for the both original state of fly ash powders and the particles obtained. This analysis shows that fly ash contains 56.23 wt.% SiO2; 20.61 wt.% Al2O3 and 17.55 wt.% Fe2O3 phases that mostly contribute to the integral (experimental) intensity of the diffraction maximum. The LTP treatment results in a complex redistribution of the amorphous phase amount in the obtained spherical particles, including the reduction of O2Si, phase, increase of O22Al20 and Fe2O3 phases and change in Al, O density of O22Al20 chemical unit cell.

In Vitro Reconstitution of Functional Type III Protein Export and Insights into Flagellar Assembly.

PubMed

Terashima, Hiroyuki; Kawamoto, Akihiro; Tatsumi, Chinatsu; Namba, Keiichi; Minamino, Tohru; Imada, Katsumi

2018-06-26

The type III secretion system (T3SS) forms the functional core of injectisomes, protein transporters that allow bacteria to deliver virulence factors into their hosts for infection, and flagella, which are critical for many pathogens to reach the site of infection. In spite of intensive genetic and biochemical studies, the T3SS protein export mechanism remains unclear due to the difficulty of accurate measurement of protein export in vivo Here, we developed an in vitro flagellar T3S protein transport assay system using an inverted cytoplasmic membrane vesicle (IMV) for accurate and controlled measurements of flagellar protein export. We show that the flagellar T3SS in the IMV fully retains export activity. The flagellar hook was constructed inside the lumen of the IMV by adding purified component proteins externally to the IMV solution. We reproduced the hook length control and export specificity switch in the IMV consistent with that seen in the native cell. Previous in vivo analyses showed that flagellar protein export is driven by proton motive force (PMF) and facilitated by ATP hydrolysis by FliI, a T3SS-specific ATPase. Our in vitro assay recapitulated these previous in vivo observations but furthermore clearly demonstrated that even ATP hydrolysis by FliI alone can drive flagellar protein export. Moreover, this assay showed that addition of the FliH 2 /FliI complex to the assay solution at a concentration similar to that in the cell dramatically enhanced protein export, confirming that the FliH 2 /FliI complex in the cytoplasm is important for effective protein transport. IMPORTANCE The type III secretion system (T3SS) is the functional core of the injectisome, a bacterial protein transporter used to deliver virulence proteins into host cells, and bacterial flagella, critical for many pathogens. The molecular mechanism of protein transport is still unclear due to difficulties in accurate measurements of protein transport under well-controlled conditions in vivo We succeeded in developing an in vitro transport assay system of the flagellar T3SS using inverted membrane vesicles (IMVs). Flagellar hook formation was reproduced in the IMV, suggesting that the export apparatus in the IMV retains a protein transport activity similar to that in the cell. Using this system, we revealed that ATP hydrolysis by the T3SS ATPase can drive protein export without PMF. Copyright © 2018 Terashima et al.

Analyzing Test-As-You-Fly Single Event Upset (SEU) Responses using SEU Data, Classical Reliability Models, and Space Environment Data

NASA Technical Reports Server (NTRS)

Berg, Melanie; Label, Kenneth; Campola, Michael; Xapsos, Michael

2017-01-01

We propose a method for the application of single event upset (SEU) data towards the analysis of complex systems using transformed reliability models (from the time domain to the particle fluence domain) and space environment data.

Characterization of toxin complex gene clusters and insect toxicity of bacteria representing four subgroups of Pseudomonas fluorescens

USDA-ARS?s Scientific Manuscript database

Ten strains representing four lineages of Pseudomonas (P. chlororaphis, P. corrugata, P. koreensis, and P. fluorescens subgroups) were evaluated for toxicity to the tobacco hornworm Manduca sexta and the fruit fly Drosophila melanogaster. The three strains within the P. chlororaphis subgroup exhibi...

Winter Biology and Freeze Tolerance in the Goldenrod Gall Fly

ERIC Educational Resources Information Center

Sandro, Luke H.; Lee, Richard E., Jr.

2006-01-01

This article describes a variety of opportunities for educational activities that can be found in the complex, yet easy-to-manipulate, trophic relationships between goldenrod plants, insects that induce gall formation, and the natural enemies of these gallmakers. Gall collection, measurement, and observation (exit holes, larval response,…

Effect of temperature on the development and survival of immature stages of the carambola fruit fly, Bactrocera carambolae, and the Asian papaya fruit fly, Bactrocera papayae, reared on guava diet.

PubMed

Danjuma, Solomon; Thaochan, Narit; Permkam, Surakrai; Satasook, Chutamas

2014-01-01

Members of the Bactrocera dorsalis Hendel (Diptera: Tephritidae) complex constitute well-recognized destructive pests of fruits in peninsular Thailand. The development and survival of immature stages of the carambola fruit fly, Bactrocera carambolae Drew & Hancock, and the Asian papaya fruit fly, Bactrocera papayae Drew & Hancock, were compared at six constant temperatures of 15, 20, 25, 27, 30, and 35°C, 70 ± 5% relative humidity, and a photoperiod of 12:12 (L:D). The objectives were to determine the effect of temperature on the developmental stages for optimizing rearing and to understand the geographical pattern of occurrence of these fruit fly species. A strong and positive linear relationship was observed between temperature and developmental rate of immature stages of B. carambolae. Similarly, a strong and positive linear relationship was observed between temperature and developmental rate of B. papayae. A temperature summation model was used to estimate the lower threshold temperature and the thermal constant. Bactrocera papayae was significantly faster in development and higher in survival and appeared to be better adapted to low temperatures than B. carambolae, as it exhibited the lowest threshold temperatures at all immature stages. The observed differences in response to various temperatures revealed to some extent the impact of temperature on these species' distribution in peninsular Thailand and other parts of the world. This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.

Microbiota-Induced Changes in Drosophila melanogaster Host Gene Expression and Gut Morphology

PubMed Central

Buchon, Nicolas

2014-01-01

ABSTRACT To elucidate mechanisms underlying the complex relationships between a host and its microbiota, we used the genetically tractable model Drosophila melanogaster. Consistent with previous studies, the microbiota was simple in composition and diversity. However, analysis of single flies revealed high interfly variability that correlated with differences in feeding. To understand the effects of this simple and variable consortium, we compared the transcriptome of guts from conventionally reared flies to that for their axenically reared counterparts. Our analysis of two wild-type fly lines identified 121 up- and 31 downregulated genes. The majority of these genes were associated with immune responses, tissue homeostasis, gut physiology, and metabolism. By comparing the transcriptomes of young and old flies, we identified temporally responsive genes and showed that the overall impact of microbiota was greater in older flies. In addition, comparison of wild-type gene expression with that of an immune-deficient line revealed that 53% of upregulated genes exerted their effects through the immune deficiency (Imd) pathway. The genes included not only classic immune response genes but also those involved in signaling, gene expression, and metabolism, unveiling new and unexpected connections between immunity and other systems. Given these findings, we further characterized the effects of gut-associated microbes on gut morphology and epithelial architecture. The results showed that the microbiota affected gut morphology through their impacts on epithelial renewal rate, cellular spacing, and the composition of different cell types in the epithelium. Thus, while bacteria in the gut are highly variable, the influence of the microbiota at large has far-reaching effects on host physiology. PMID:24865556

Cloning of the neurodegeneration gene drop-dead and characterization of additional phenotypes of its mutation.

PubMed

Blumenthal, Edward M

2008-01-01

Mutations in the Drosophila gene drop-dead (drd) result in early adult lethality and neurodegeneration, but the molecular identity of the drd gene and its mechanism of action are not known. This paper describes the characterization of a new X-linked recessive adult-lethal mutation, originally called lot's wife (lwf(1)) but subsequently identified as an allele of drd (drd(lwf)); drd(lwf) mutants die within two weeks of eclosion. Through mapping and complementation, the drd gene has been identified as CG33968, which encodes a putative integral membrane protein of unknown function. The drd(lwf) allele is associated with a nonsense mutation that eliminates nearly 80% of the CG33968 gene product; mutations in the same gene were also found in two previously described drd alleles. Characterization of drd (lwf) flies revealed additional phenotypes of drd, most notably, defects in food processing by the digestive system and in oogenesis. Mutant flies store significantly more food in their crops and defecate less than wild-type flies, suggesting that normal transfer of ingested food from the crop into the midgut is dependent upon the DRD gene product. The defect in oogenesis results in the sterility of homozygous mutant females and is associated with a reduction in the number of vitellogenic egg chambers. The disruption in vitellogenesis is far more severe than that seen in starved flies and so is unlikely to be a secondary consequence of the digestive phenotype. This study demonstrates that mutation of the drd gene CG33968 results in a complex phenotype affecting multiple physiological systems within the fly.

[Research advance of dosage compensation and MSL complex].

PubMed

Sun, Min-Qiu; Lin, Peng; Chen, Yun; Wang, Yi-Lei; Zhang, Zi-Ping

2012-05-01

Dosage compensation effect, which exists widely in eukaryotes with sexual reproduction, is an essential biological process that equalizes the level of gene expression between genders based on sex determination. In Drosophila, the male-specific lethal (MSL) complex mediates dosage compensation by acetylating histone H4 lysine K16 on nucleosome of some specific sites on the male X chromosome, globally upregulates twofold expression of active X-linked genes from the single X chromosome, and makes up for the shortage that the male has only one single X chromosome in male Drosophila. Up to date, the structure of basic components of MSL complex, which consists of at least five protein subunits and two non-coding RNAs, has already been revealed, and the interaction sites among these components have also been generally identified. Furthermore, abundant researches on recognition mechanism of the complex have been published. In contrast, many studies have revealed that mammalian dosage compensation functions by silencing gene expression from one of the two X chromosomes in females. The main components of mammalian MSL complex have already been identified, but the knowledge of their function is limited. Up to now, research of MSLs in teleosts is scarcely studied. This review summarizes the similarities and differences among dosage compensation mechanisms of nematodes, fruit flies and mammals, introduces the recent research advances in MSL complex, as well as molecular mechanism of dosage compensation in fruit fly, and finally addresses some problems to be resolved. Meanwhile, the diversity of msl3 gene in fishes is found by synteny analysis. This information might provide insightful directions for future research on the mechanisms of dosage compensation in various species.

The Smc5/Smc6/MAGE Complex Confers Resistance to Caffeine and Genotoxic Stress in Drosophila melanogaster

PubMed Central

Li, Xiao; Zhuo, Ran; Tiong, Stanley; Di Cara, Francesca; King-Jones, Kirst; Hughes, Sarah C.; Campbell, Shelagh D.; Wevrick, Rachel

2013-01-01

The SMC5/6 protein complex consists of the Smc5, Smc6 and Non-Smc-Element (Nse) proteins and is important for genome stability in many species. To identify novel components in the DNA repair pathway, we carried out a genetic screen to identify mutations that confer reduced resistance to the genotoxic effects of caffeine, which inhibits the ATM and ATR DNA damage response proteins. This approach identified inactivating mutations in CG5524 and MAGE, homologs of genes encoding Smc6 and Nse3 in yeasts. The fact that Smc5 mutants are also caffeine-sensitive and that Mage physically interacts with Drosophila homologs of Nse proteins suggests that the structure of the Smc5/6 complex is conserved in Drosophila. Although Smc5/6 proteins are required for viability in S. cerevisiae, they are not essential under normal circumstances in Drosophila. However, flies carrying mutations in Smc5, Smc6 and MAGE are hypersensitive to genotoxic agents such as ionizing radiation, camptothecin, hydroxyurea and MMS, consistent with the Smc5/6 complex serving a conserved role in genome stability. We also show that mutant flies are not compromised for pre-mitotic cell cycle checkpoint responses. Rather, caffeine-induced apoptosis in these mutants is exacerbated by inhibition of ATM or ATR checkpoint kinases but suppressed by Rad51 depletion, suggesting a functional interaction involving homologous DNA repair pathways that deserves further scrutiny. Our insights into the SMC5/6 complex provide new challenges for understanding the role of this enigmatic chromatin factor in multi-cellular organisms. PMID:23555814

Simple Ways to Measure Behavioral Responses of Drosophila to Stimuli and Use of These Methods to Characterize a Novel Mutant

PubMed Central

Vang, Lar L.; Medvedev, Alexei V.; Adler, Julius

2012-01-01

The behavioral responses of adult Drosophila fruit flies to a variety of sensory stimuli – light, volatile and non-volatile chemicals, temperature, humidity, gravity, and sound - have been measured by others previously. Some of those assays are rather complex; a review of them is presented in the Discussion. Our objective here has been to find out how to measure the behavior of adult Drosophila fruit flies by methods that are inexpensive and easy to carry out. These new assays have now been used here to characterize a novel mutant that fails to be attracted or repelled by a variety of sensory stimuli even though it is motile. PMID:22649531

The Geo Quick Ride (GQR) Program: Providing Inexpensive and Frequent Access to Space

NASA Technical Reports Server (NTRS)

Caffrey, Robert; Baniszewski, John

2004-01-01

This paper examines piggybacking NASA, university, and industry payloads on commercial geosynchronous satellites. NASA's RSDO Office awarded Geo Quick Ride (GQR) study contracts in 1998 to spacecraft manufactures to examine the issues with flying secondary payloads. The study results were very promising. Commercial communication satellites have frequent flights and significant unused resources that could be used to fly secondary payloads. However, manifesting secondary payloads on a commercial revenue-generating satellite is a complex problem to solve. The solution requires multiple simultaneous approaches in order to be successful. There are business, economic, technical, schedule, and organizational issues to be resolved. This paper examines the Geo Quick Ride (GQR) concept, discusses the development issues, and describes how this concept solves many of these issues.

Problem-Solving Test: Targeted Gene Disruption

ERIC Educational Resources Information Center

Szeberenyi, Jozsef

2008-01-01

Mutational inactivation of a specific gene is the most powerful technique to analyze the biological function of the gene. This approach has been used for a long time in viruses, bacteria, yeast, and fruit fly, but looked quite hopeless in more complex organisms. Targeted inactivation of specific genes (also known as knock-out mutation) in mice is…

Watershed Management For Endangered Aquatic and Riparian Species: Facts and Fallacies

Treesearch

D.G. Neary; J.N. Rinne; A.L. Medina; M.B. Baker; J.L. Michael

2000-01-01

River basin management is becoming increasingly complex in the United States since watershed managers are required to take into consideration the threatened and endangered (T&E) species that inhabit aquatic and riparian ecosystems. Unfortunately too many fallacies and political agendas have crept into the picture. Suppositions and hypotheses fly everywhere in the...

Integrative taxonomy: Where we are now, with a focus on the resolution of three tropical fruit fly species complexes

USDA-ARS?s Scientific Manuscript database

Accurate species delimitation underpins good taxonomy. Formalisation of integrative taxonomy in the last decade has provided a framework for using multidisciplinary data to increase rigor in species delimitation hypotheses. We address the state of integrative taxonomy by using an international proje...

An insight into the transcriptome and proteome of the salivary gland of the stable fly, Stomoxys calcitrans.

PubMed

Wang, Xuyong; Ribeiro, José M C; Broce, Alberto B; Wilkerson, Melinda J; Kanost, Michael R

2009-09-01

Adult stable flies are blood feeders, a nuisance, and mechanical vectors of veterinary diseases. To enable efficient feeding, blood sucking insects have evolved a sophisticated array of salivary compounds to disarm their host's hemostasis and inflammatory reaction. While the sialomes of several blood sucking Nematocera flies have been described, no thorough description has been made so far of any Brachycera, except for a detailed proteome analysis of a tabanid (Xu et al., 2008). In this work we provide an insight into the sialome of the muscid Stomoxys calcitrans, revealing a complex mixture of serine proteases, endonucleases, Kazal-containing peptides, anti-thrombins, antigen 5 related proteins, antimicrobial peptides, and the usual finding of mysterious secreted peptides that have no known partners, and may reflect the very fast evolution of salivary proteins due to the vertebrate host immune pressure. Supplemental Tables S1 and S2 can be downloaded from http://exon.niaid.nih.gov/transcriptome/S_calcitrans/T1/Sc-tb1-web.xls and http://exon.niaid.nih.gov/transcriptome/S_calcitrans/T2/Sc-tb2-web.xls.

Pro-apoptotic effect of fly ash leachates in hepatocytes of freshwater fish (Channa punctata Bloch).

PubMed

Ali, Mehboob; Rahman, Shakilur; Rehman, Hasibur; Bhatia, Kanchan; Ansari, Rizwan A; Raisuddin, Sheikh

2007-02-01

The pro-apoptotic effect of fly ash leachates (FAL) was studied in the hepatocytes of an Indian freshwater fish, Channa punctata Bloch. Hepatocytes were exposed to different concentrations of '7-day' FAL for 24 and 48h and various parameters of apoptosis were studied using standardized procedures. FAL-induced apoptosis in hepatocytes was indicated by cytological examination, DNA fragmentation and DNA laddering. The induction in cytochrome-c release, caspases 3, 7, 10 and 9 activities and lactate dehydrogenase level provide mechanistic platform for FAL-induced apoptosis. Cytological examination showed an unambiguous apoptotic effect of ash leachates in fish hepatocytes. Exposed hepatocytes also showed increased production of H(2)O(2), superoxide ions and an increase in lipid peroxidation (LPO). The present study suggests a possible role of reactive oxygen species (ROS) in FAL-induced apoptosis in hepatocytes. Lactate dehydrogenase, LPO and apoptosis as biomarkers of cytotoxicity have recently been used for assessment of ecotoxicological impact of environmental chemicals. Our findings show that these biomarkers may also be used for evaluation of ecotoxicological impact of complex chemical mixture such as fly ash and its leachates.

An insight into the transcriptome and proteome of the salivary gland of the stable fly, Stomoxys calcitrans

PubMed Central

Wang, Xuyong; Ribeiro, José M. C.; Broce, Alberto B.; Wilkerson, Melinda J.; Kanost, Michael R.

2009-01-01

Adult stable flies are blood feeders, a nuisance, and mechanical vectors of veterinary diseases. To enable efficient feeding, blood sucking insects have evolved a sophisticated array of salivary compounds to disarm their host's hemostasis and inflammatory reaction. While the sialomes of several blood sucking Nematocera flies have been described, no thorough description has been made so far of any Brachycera, except for a detailed proteome analysis of a tabanid (Xu et al., 2008). In this work we provide an insight into the sialome of the muscid Stomoxys calcitrans, revealing a complex mixture of serine proteases, endonucleases, Kazal-containing peptides, anti-thrombins, antigen-5 related proteins, antimicrobial peptides, and the usual finding of mysterious secreted peptides that have no known partners, and may reflect the very fast evolution of salivary proteins due to the vertebrate host immune pressure. Supplemental tables S1 and S2 can be downloaded from http://exon.niaid.nih.gov/transcriptome/S_calcitrans/T1/Sc-tb1-web.xls and http://exon.niaid.nih.gov/transcriptome/S_calcitrans/T2/Sc-tb2-web.xls. PMID:19576987

The Drosophila melanogaster homolog of UBE3A is not imprinted in neurons.

PubMed

Hope, Kevin A; LeDoux, Mark S; Reiter, Lawrence T

2016-09-01

In mammals, expression of UBE3A is epigenetically regulated in neurons and expression is restricted to the maternal copy of UBE3A. A recent report claimed that Drosophila melanogaster UBE3A homolog (Dube3a) is preferentially expressed from the maternal allele in fly brain, inferring an imprinting mechanism. However, complex epigenetic regulatory features of the mammalian imprinting center are not present in Drosophila, and allele specific expression of Dube3a has not been documented. We used behavioral and electrophysiological analysis of the Dube3a loss-of-function allele (Dube3a 15b ) to investigate Dube3a imprinting in fly neurons. We found that motor impairment (climbing ability) and a newly-characterized defect in synaptic transmission are independent of parental inheritance of the Dube3a 15b allele. Furthermore, expression analysis of coding single nucleotide polymorphisms (SNPs) in Dube3a did not reveal allele specific expression differences among reciprocal crosses. These data indicate that Dube3a is neither imprinted nor preferentially expressed from the maternal allele in fly neurons.

Acetylcholinesterases of blood-feeding flies and ticks.

PubMed

Temeyer, Kevin B; Tuckow, Alexander P; Brake, Danett K; Li, Andrew Y; Pérez de León, Adalberto A

2013-03-25

Acetylcholinesterase (AChE) is the biochemical target of organophosphate (OP) and carbamate pesticides for invertebrates, vertebrate nerve agents, and AChE inhibitors used to reduce effects of Alzheimer's disease. Organophosphate pesticides (OPs) are widely used to control blood-feeding arthropods, including biting flies and ticks. However, resistance to OPs in pests affecting animal and human health has compromised control efficacy. OP resistance often results from mutations producing an OP-insensitive AChE. Our studies have demonstrated production of OP-insensitive AChEs in biting flies and ticks. Complementary DNA (cDNA) sequences encoding AChEs were obtained for the horn fly, stable fly, sand fly, and the southern cattle tick. The availability of cDNA sequences enables the identification of mutations, expression and characterization of recombinant proteins, gene silencing for functional studies, as well as in vitro screening of novel inhibitors. The southern cattle tick expresses at least three different genes encoding AChE in their synganglion, i.e. brain. Gene amplification for each of the three known cattle tick AChE genes and expression of multiple alleles for each gene may reduce fitness cost associated with OP-resistance. AChE hydrolyzes the neurotransmitter, acetylcholine, but may have additional roles in physiology and development. The three cattle tick AChEs possess significantly different biochemical properties, and are expressed in neural and non-neural tissues, which suggest separation of structure and function. The remarkable complexity of AChEs in ticks suggested by combining genomic data from Ixodes scapularis with our genetic and biochemical data from Rhipicephalus microplus is suggestive of previously unknown gene duplication and diversification. Comparative studies between invertebrate and vertebrate AChEs could enhance our understanding of structure-activity relationships. Research with ticks as a model system offers the opportunity to elucidate structure-activity relationships for AChE that are important for advances in targeted pest control, as well as potential applications for medicine and biosecurity. Published by Elsevier Ireland Ltd.

Exploring Valleys without Climbing Every Peak: More Efficient and Forgiving Metabasin Metadynamics via Robust On-the-Fly Bias Domain Restriction

PubMed Central

2015-01-01

Metadynamics is an enhanced sampling method designed to flatten free energy surfaces uniformly. However, the highest-energy regions are often irrelevant to study and dangerous to explore because systems often change irreversibly in unforeseen ways in response to driving forces in these regions, spoiling the sampling. Introducing an on-the-fly domain restriction allows metadynamics to flatten only up to a specified energy level and no further, improving efficiency and safety while decreasing the pressure on practitioners to design collective variables that are robust to otherwise irrelevant high energy driving. This paper describes a new method that achieves this using sequential on-the-fly estimation of energy wells and redefinition of the metadynamics hill shape, termed metabasin metadynamics. The energy level may be defined a priori or relative to unknown barrier energies estimated on-the-fly. Altering only the hill ensures that the method is compatible with many other advances in metadynamics methodology. The hill shape has a natural interpretation in terms of multiscale dynamics, and the computational overhead in simulation is minimal when studying systems of any reasonable size, for instance proteins or other macromolecules. Three example applications show that the formula is accurate and robust to complex dynamics, making metadynamics significantly more forgiving with respect to CV quality and thus more feasible to apply to the most challenging biomolecular systems. PMID:26587809

Wing-pitch modulation in maneuvering fruit flies is explained by an interplay between aerodynamics and a torsional spring.

PubMed

Beatus, Tsevi; Cohen, Itai

2015-08-01

While the wing kinematics of many flapping insects have been well characterized, understanding the underlying sensory, neural, and physiological mechanisms that determine these kinematics is still a challenge. Two main difficulties in understanding the physiological mechanisms arise from the complexity of the interaction between a flapping wing and its own unsteady flow, as well as the intricate mechanics of the insect wing hinge, which is among the most complicated joints in the animal kingdom. These difficulties call for the application of reduced-order approaches. Here this strategy is used to model the torques exerted by the wing hinge along the wing-pitch axis of maneuvering fruit flies as a damped torsional spring with elastic and damping coefficients as well as a rest angle. Furthermore, we model the air flows using simplified quasistatic aerodynamics. Our findings suggest that flies take advantage of the passive coupling between aerodynamics and the damped torsional spring to indirectly control their wing-pitch kinematics by modulating the spring parameters. The damped torsional-spring model explains the changes measured in wing-pitch kinematics during roll correction maneuvers through modulation of the spring damping and elastic coefficients. These results, in conjunction with the previous literature, indicate that flies can accurately control their wing-pitch kinematics on a sub-wing-beat time scale by modulating all three effective spring parameters on longer time scales.

Wing-pitch modulation in maneuvering fruit flies is explained by an interplay between aerodynamics and a torsional spring

NASA Astrophysics Data System (ADS)

Beatus, Tsevi; Cohen, Itai

2015-08-01

While the wing kinematics of many flapping insects have been well characterized, understanding the underlying sensory, neural, and physiological mechanisms that determine these kinematics is still a challenge. Two main difficulties in understanding the physiological mechanisms arise from the complexity of the interaction between a flapping wing and its own unsteady flow, as well as the intricate mechanics of the insect wing hinge, which is among the most complicated joints in the animal kingdom. These difficulties call for the application of reduced-order approaches. Here this strategy is used to model the torques exerted by the wing hinge along the wing-pitch axis of maneuvering fruit flies as a damped torsional spring with elastic and damping coefficients as well as a rest angle. Furthermore, we model the air flows using simplified quasistatic aerodynamics. Our findings suggest that flies take advantage of the passive coupling between aerodynamics and the damped torsional spring to indirectly control their wing-pitch kinematics by modulating the spring parameters. The damped torsional-spring model explains the changes measured in wing-pitch kinematics during roll correction maneuvers through modulation of the spring damping and elastic coefficients. These results, in conjunction with the previous literature, indicate that flies can accurately control their wing-pitch kinematics on a sub-wing-beat time scale by modulating all three effective spring parameters on longer time scales.

The secondary structure of the ets domain of human Fli-1 resembles that of the helix-turn-helix DNA-binding motif of the Escherichia coli catabolite gene activator protein.

PubMed Central

Liang, H; Olejniczak, E T; Mao, X; Nettesheim, D G; Yu, L; Thompson, C B; Fesik, S W

1994-01-01

The ets family of eukaryotic transcription factors is characterized by a conserved DNA-binding domain of approximately 85 amino acids for which the three-dimensional structure is not known. By using multidimensional NMR spectroscopy, we have determined the secondary structure of the ets domain of one member of this gene family, human Fli-1, both in the free form and in a complex with a 16-bp cognate DNA site. The secondary structure of the Fli-1 ets domain consists of three alpha-helices and a short four-stranded antiparallel beta-sheet. This secondary structure arrangement resembles that of the DNA-binding domain of the catabolite gene activator protein of Escherichia coli, as well as those of several eukaryotic DNA-binding proteins including histone H5, HNF-3/fork head, and the heat shock transcription factor. Differences in chemical shifts of backbone resonances and amide exchange rates between the DNA-bound and free forms of the Fli-1 ets domain suggest that the third helix is the DNA recognition helix, as in the catabolite gene activator protein and other structurally related proteins. These results suggest that the ets domain is structurally similar to the catabolite gene activator protein family of helix-turn-helix DNA-binding proteins. Images PMID:7972119

Post-eclosion odor experience modifies olfactory receptor neuron coding in Drosophila

PubMed Central

Iyengar, Atulya; Chakraborty, Tuhin Subhra; Goswami, Sarit Pati; Wu, Chun-Fang; Siddiqi, Obaid

2010-01-01

Olfactory responses of Drosophila undergo pronounced changes after eclosion. The flies develop attraction to odors to which they are exposed and aversion to other odors. Behavioral adaptation is correlated with changes in the firing pattern of olfactory receptor neurons (ORNs). In this article, we present an information-theoretic analysis of the firing pattern of ORNs. Flies reared in a synthetic odorless medium were transferred after eclosion to three different media: (i) a synthetic medium relatively devoid of odor cues, (ii) synthetic medium infused with a single odorant, and (iii) complex cornmeal medium rich in odors. Recordings were made from an identified sensillum (type II), and the Jensen–Shannon divergence (DJS) was used to assess quantitatively the differences between ensemble spike responses to different odors. Analysis shows that prolonged exposure to ethyl acetate and several related esters increases sensitivity to these esters but does not improve the ability of the fly to distinguish between them. Flies exposed to cornmeal display varied sensitivity to these odorants and at the same time develop greater capacity to distinguish between odors. Deprivation of odor experience on an odorless synthetic medium leads to a loss of both sensitivity and acuity. Rich olfactory experience thus helps to shape the ORNs response and enhances its discriminative power. The experiments presented here demonstrate an experience-dependent adaptation at the level of the receptor neuron. PMID:20448199

Post-eclosion odor experience modifies olfactory receptor neuron coding in Drosophila.

PubMed

Iyengar, Atulya; Chakraborty, Tuhin Subhra; Goswami, Sarit Pati; Wu, Chun-Fang; Siddiqi, Obaid

2010-05-25

Olfactory responses of Drosophila undergo pronounced changes after eclosion. The flies develop attraction to odors to which they are exposed and aversion to other odors. Behavioral adaptation is correlated with changes in the firing pattern of olfactory receptor neurons (ORNs). In this article, we present an information-theoretic analysis of the firing pattern of ORNs. Flies reared in a synthetic odorless medium were transferred after eclosion to three different media: (i) a synthetic medium relatively devoid of odor cues, (ii) synthetic medium infused with a single odorant, and (iii) complex cornmeal medium rich in odors. Recordings were made from an identified sensillum (type II), and the Jensen-Shannon divergence (D(JS)) was used to assess quantitatively the differences between ensemble spike responses to different odors. Analysis shows that prolonged exposure to ethyl acetate and several related esters increases sensitivity to these esters but does not improve the ability of the fly to distinguish between them. Flies exposed to cornmeal display varied sensitivity to these odorants and at the same time develop greater capacity to distinguish between odors. Deprivation of odor experience on an odorless synthetic medium leads to a loss of both sensitivity and acuity. Rich olfactory experience thus helps to shape the ORNs response and enhances its discriminative power. The experiments presented here demonstrate an experience-dependent adaptation at the level of the receptor neuron.

Pest control of aphids depends on landscape complexity and natural enemy interactions

PubMed Central

Reineking, Björn; Seo, Bumsuk; Steffan-Dewenter, Ingolf

2015-01-01

Aphids are a major concern in agricultural crops worldwide, and control by natural enemies is an essential component of the ecological intensification of agriculture. Although the complexity of agricultural landscapes is known to influence natural enemies of pests, few studies have measured the degree of pest control by different enemy guilds across gradients in landscape complexity. Here, we use multiple natural-enemy exclosures replicated in 18 fields across a gradient in landscape complexity to investigate (1) the strength of natural pest control across landscapes, measured as the difference between pest pressure in the presence and in the absence of natural enemies; (2) the differential contributions of natural enemy guilds to pest control, and the nature of their interactions across landscapes. We show that natural pest control of aphids increased up to six-fold from simple to complex landscapes. In the absence of pest control, aphid population growth was higher in complex than simple landscapes, but was reduced by natural enemies to similar growth rates across all landscapes. The effects of enemy guilds were landscape-dependent. Particularly in complex landscapes, total pest control was supplied by the combined contribution of flying insects and ground-dwellers. Birds had little overall impact on aphid control. Despite evidence for intraguild predation of flying insects by ground-dwellers and birds, the overall effect of enemy guilds on aphid control was complementary. Understanding pest control services at large spatial scales is critical to increase the success of ecological intensification schemes. Our results suggest that, where aphids are the main pest of concern, interactions between natural enemies are largely complementary and lead to a strongly positive effect of landscape complexity on pest control. Increasing the availability of seminatural habitats in agricultural landscapes may thus benefit not only natural enemies, but also the effectiveness of aphid natural pest control. PMID:26734497

Pest control of aphids depends on landscape complexity and natural enemy interactions.

PubMed

Martin, Emily A; Reineking, Björn; Seo, Bumsuk; Steffan-Dewenter, Ingolf

2015-01-01

Aphids are a major concern in agricultural crops worldwide, and control by natural enemies is an essential component of the ecological intensification of agriculture. Although the complexity of agricultural landscapes is known to influence natural enemies of pests, few studies have measured the degree of pest control by different enemy guilds across gradients in landscape complexity. Here, we use multiple natural-enemy exclosures replicated in 18 fields across a gradient in landscape complexity to investigate (1) the strength of natural pest control across landscapes, measured as the difference between pest pressure in the presence and in the absence of natural enemies; (2) the differential contributions of natural enemy guilds to pest control, and the nature of their interactions across landscapes. We show that natural pest control of aphids increased up to six-fold from simple to complex landscapes. In the absence of pest control, aphid population growth was higher in complex than simple landscapes, but was reduced by natural enemies to similar growth rates across all landscapes. The effects of enemy guilds were landscape-dependent. Particularly in complex landscapes, total pest control was supplied by the combined contribution of flying insects and ground-dwellers. Birds had little overall impact on aphid control. Despite evidence for intraguild predation of flying insects by ground-dwellers and birds, the overall effect of enemy guilds on aphid control was complementary. Understanding pest control services at large spatial scales is critical to increase the success of ecological intensification schemes. Our results suggest that, where aphids are the main pest of concern, interactions between natural enemies are largely complementary and lead to a strongly positive effect of landscape complexity on pest control. Increasing the availability of seminatural habitats in agricultural landscapes may thus benefit not only natural enemies, but also the effectiveness of aphid natural pest control.

Wolbachia infection complexity among insects in the tropical rice-field community.

PubMed

Kittayapong, P; Jamnongluk, W; Thipaksorn, A; Milne, J R; Sindhusake, C

2003-04-01

Wolbachia are a group of intracellular bacteria that cause reproductive alterations in their arthropod hosts. Widely discordant host and Wolbachia phylogenies indicate that horizontal transmission of these bacteria among species sometimes occurs. A likely means of horizontal transfer is through the feeding relations of organisms within communities. Feeding interactions among insects within the rice-field insect community have been well documented in the past. Here, we present the results of a polymerase chain reaction-based survey and phylogenetic analysis of Wolbachia strains in the rice-field insect community of Thailand. Our field survey indicated that 49 of 209 (23.4%) rice-field insect species were infected with Wolbachia. Of the 49 infected species, 27 were members of two feeding complexes: (i) a group of 13 hoppers preyed on by 2 mirid species and parasitized by a fly species, and (ii) 2 lepidopteran pests parasitized by 9 wasp species. Wolbachia strains found in three hoppers, Recilia dorsalis, Nephotettix malayanus and Nisia nervosa, the two mirid predators, Cyrtorhinus lividipennis and Tytthus chinensis, and the fly parasitoid, Tomosvaryella subvirescens, were all in the same Wolbachia clade. In the second complex, the two lepidopteran pests, Cnaphalocrocis medinalis and Scirpophaga incertulas, were both infected with Wolbachia from the same clade, as was the parasitoid Tropobracon schoenobii. However, none of the other infected parasitoid species in this feeding complex was infected by Wolbachia from this clade. Mean (+/- SD) genetic distance of Wolbachia wsp sequences among interacting species pairs of the hopper feeding complex (0.118 +/- 0.091 nucleotide sequence differences), but not for the other two complexes, was significantly smaller than that between noninteracting species pairs (0.162 +/- 0.079 nucleotide sequence differences). Our results suggest that some feeding complexes, such as the hopper complex described here, could be an important means by which Wolbachia spreads among species within arthropod communities.

The NSL Complex Regulates Housekeeping Genes in Drosophila

PubMed Central

Raja, Sunil Jayaramaiah; Holz, Herbert; Luscombe, Nicholas M.; Manke, Thomas; Akhtar, Asifa

2012-01-01

MOF is the major histone H4 lysine 16-specific (H4K16) acetyltransferase in mammals and Drosophila. In flies, it is involved in the regulation of X-chromosomal and autosomal genes as part of the MSL and the NSL complexes, respectively. While the function of the MSL complex as a dosage compensation regulator is fairly well understood, the role of the NSL complex in gene regulation is still poorly characterized. Here we report a comprehensive ChIP–seq analysis of four NSL complex members (NSL1, NSL3, MBD-R2, and MCRS2) throughout the Drosophila melanogaster genome. Strikingly, the majority (85.5%) of NSL-bound genes are constitutively expressed across different cell types. We find that an increased abundance of the histone modifications H4K16ac, H3K4me2, H3K4me3, and H3K9ac in gene promoter regions is characteristic of NSL-targeted genes. Furthermore, we show that these genes have a well-defined nucleosome free region and broad transcription initiation patterns. Finally, by performing ChIP–seq analyses of RNA polymerase II (Pol II) in NSL1- and NSL3-depleted cells, we demonstrate that both NSL proteins are required for efficient recruitment of Pol II to NSL target gene promoters. The observed Pol II reduction coincides with compromised binding of TBP and TFIIB to target promoters, indicating that the NSL complex is required for optimal recruitment of the pre-initiation complex on target genes. Moreover, genes that undergo the most dramatic loss of Pol II upon NSL knockdowns tend to be enriched in DNA Replication–related Element (DRE). Taken together, our findings show that the MOF-containing NSL complex acts as a major regulator of housekeeping genes in flies by modulating initiation of Pol II transcription. PMID:22723752

Quaternary Morphodynamics of Fluvial Dispersal Systems Revealed: The Fly River, PNG, and the Sunda Shelf, SE Asia, simulated with the Massively Parallel GPU-based Model 'GULLEM'

NASA Astrophysics Data System (ADS)

Aalto, R. E.; Lauer, J. W.; Darby, S. E.; Best, J.; Dietrich, W. E.

2015-12-01

During glacial-marine transgressions vast volumes of sediment are deposited due to the infilling of lowland fluvial systems and shallow shelves, material that is removed during ensuing regressions. Modelling these processes would illuminate system morphodynamics, fluxes, and 'complexity' in response to base level change, yet such problems are computationally formidable. Environmental systems are characterized by strong interconnectivity, yet traditional supercomputers have slow inter-node communication -- whereas rapidly advancing Graphics Processing Unit (GPU) technology offers vastly higher (>100x) bandwidths. GULLEM (GpU-accelerated Lowland Landscape Evolution Model) employs massively parallel code to simulate coupled fluvial-landscape evolution for complex lowland river systems over large temporal and spatial scales. GULLEM models the accommodation space carved/infilled by representing a range of geomorphic processes, including: river & tributary incision within a multi-directional flow regime, non-linear diffusion, glacial-isostatic flexure, hydraulic geometry, tectonic deformation, sediment production, transport & deposition, and full 3D tracking of all resulting stratigraphy. Model results concur with the Holocene dynamics of the Fly River, PNG -- as documented with dated cores, sonar imaging of floodbasin stratigraphy, and the observations of topographic remnants from LGM conditions. Other supporting research was conducted along the Mekong River, the largest fluvial system of the Sunda Shelf. These and other field data provide tantalizing empirical glimpses into the lowland landscapes of large rivers during glacial-interglacial transitions, observations that can be explored with this powerful numerical model. GULLEM affords estimates for the timing and flux budgets within the Fly and Sunda Systems, illustrating complex internal system responses to the external forcing of sea level and climate. Furthermore, GULLEM can be applied to most ANY fluvial system to explore processes across a wide range of temporal and spatial scales. The presentation will provide insights (& many animations) illustrating river morphodynamics & resulting landscapes formed as a result of sea level oscillations. [Image: The incised 3.2e6 km^2 Sundaland domain @ 431ka

2017 ASCAN Tour of KSC

NASA Image and Video Library

2018-05-02

The 2017 class of astronaut candidates are at United Launch Alliance's Space Launch Complex 41 at Cape Canaveral Air Force Station (CCAFS) in Florida for a familiarization tour. They also toured facilities at Kennedy Space Center, including the Neil Armstrong Operations and Checkout Building high bay; the Launch Control Center, Launch Complex 39B, the Vehicle Assembly Building, Boeing's Commercial Crew and Cargo Facility, and SpaceX's Launch Complex 39A. The candidates will spend about two years getting to know the space station systems and learning how to spacewalk, speak Russian, control the International Space Station's robotic arm and fly T-38s, before they're eligible to be assigned to a mission.

[Development of spatial orientation during pilot training].

PubMed

Ivanov, V V; Vorob'ev, O A; Snipkov, Iu Iu

1988-01-01

The problem of spatial orientation of pilots flying high-altitude aircraft is in the focus of present-day aviation medicine because of a growing number of accidents in the air. One of the productive lines of research is to study spatial orientation in terms of active formation and maintenance of its imagery in a complex environment. However investigators usually emphasize the role of visual (instrumental) information in the image construction, almost ignoring the sensorimotor component of spatial orientation. The theoretical analysis of the process of spatial orientation has facilitated the development of the concept assuming that the pattern of space perception changes with growing professional experience. The concept is based on an active approach to the essence, emergence, formation and variation in the pattern of sensory perception of space in man's consciousness. This concept asserts that as pilot's professional expertise increases, the pattern of spatial orientation becomes geocentric because a new system of spatial perception evolves which is a result of the development of a new (instrumental) type of motor activity in space. This finds expression in the fact that perception of spatial position inflight occurs when man has to resolve a new motor task--movement along a complex trajectory in the three-dimensional space onboard a flying vehicle. The meaningful structure of this problem which is to be implemented through controlling movements of the pilot acts as a factor that forms this new system of perception. All this underlies the arrangement of meaningful collection of instrumental data and detection of noninstrumental signals in the comprehensive perception of changes in the spatial position of a flying vehicle.

Socialized sub-groups in a temporary stable Raven flock?

PubMed Central

Braun, Anna; Walsdorff, Thomas; Fraser, Orlaith N.; Bugnyar, Thomas

2015-01-01

A complex social life serves as one of the main driving forces behind the evolution of higher cognitive abilities in vertebrates. In birds, however, data are primarily derived from captive animals, which strongly contrast with free-flying birds in terms of the number of interaction partners as well as available space. In captivity, Common Raven Corvus corax, nonbreeder groups show strong social bonds and complex tactical manoeuvring, whereas wild non-breeders are thought to resemble anonymous aggregations. Over 2 years, we observed a free-flying population of Ravens that visits a game park in the northern Alps. We here focus on the daily fission–fusion dynamics, individual spacing, and the influence of spacing on the birds’ agonistic and affiliative behaviour. The composition of marked Ravens in the local population changed slowly but constantly, although often remaining stable for several weeks. Birds only flocked for feeding, mobbing and roosting, and spent the rest of the day in loose aggregations, characterised by temporary small subgroups of 2–5 individuals. Aggression was high during crowd foraging but low outside of a feeding context. Affiliative behaviours, such as sitting within reaching distance, allo-preening and social play, were observed particularly in the small subgroups. These findings suggest that Raven aggregations are not as unstructured as previously thought. Birds may spend time and/or interact affilliatively with multiple individuals during the day. This, along with temporary stability in group composition, provides the opportunity for social relationships to develop, and enables the existence of socialised subgroups within free-flying Raven aggregations. PMID:25892747

Formation Flying of Tethered and Nontethered Spacecraft

NASA Technical Reports Server (NTRS)

Quadrelli, Marco B.

2005-01-01

A paper discusses the effect of the dynamic interaction taking place within a formation composed of a rigid and a deformable vehicle, and presents the concept of two or more tethered spacecraft flying in formation with one or more separated free-flying spacecraft. Although progress toward formation flight of nontethered spacecraft has already been achieved, the document cites potential advantages of tethering, including less consumption of fuel to maintain formation, very high dynamic stability of a rotating tethered formation, and intrinsically passive gravity-gradient stabilization. The document presents a theoretical analysis of the dynamics of a system comprising one free-flying spacecraft and two tethered spacecraft in orbit, as a prototype of more complex systems. The spacecraft are modeled as rigid bodies and the tether as a mass-less spring with structural viscous damping. Included in the analysis is a study of the feasibility of a centralized control system for maintaining a required formation in low Earth orbit. A numerical simulation of a retargeting maneuver is reported to show that even if the additional internal dynamics of the system caused by flexibility is considered, high pointing precision can be achieved if a fictitious rigid frame is used to track the tethered system, and it should be possible to position the spacecraft with centimeter accuracy and to orient the formation within arc seconds of the desired direction also in the presence of low Earth orbit environmental perturbations. The results of the study demonstrate that the concept is feasible in Earth orbit and point the way to further study of these hybrid tethered and free-flying systems for related applications in orbit around other Solar System bodies.

Leishmania HASP and SHERP Genes Are Required for In Vivo Differentiation, Parasite Transmission and Virulence Attenuation in the Host

PubMed Central

Doehl, Johannes S. P.; Sádlová, Jovana; Aslan, Hamide; Pružinová, Kateřina; Votýpka, Jan; Kamhawi, Shaden; Volf, Petr

2017-01-01

Differentiation of extracellular Leishmania promastigotes within their sand fly vector, termed metacyclogenesis, is considered to be essential for parasites to regain mammalian host infectivity. Metacyclogenesis is accompanied by changes in the local parasite environment, including secretion of complex glycoconjugates within the promastigote secretory gel and colonization and degradation of the sand fly stomodeal valve. Deletion of the stage-regulated HASP and SHERP genes on chromosome 23 of Leishmania major is known to stall metacyclogenesis in the sand fly but not in in vitro culture. Here, parasite mutants deficient in specific genes within the HASP/SHERP chromosomal region have been used to investigate their role in metacyclogenesis, parasite transmission and establishment of infection. Metacyclogenesis was stalled in HASP/SHERP mutants in vivo and, although still capable of osmotaxis, these mutants failed to secrete promastigote secretory gel, correlating with a lack of parasite accumulation in the thoracic midgut and failure to colonise the stomodeal valve. These defects prevented parasite transmission to a new mammalian host. Sand fly midgut homogenates modulated parasite behaviour in vitro, suggesting a role for molecular interactions between parasite and vector in Leishmania development within the sand fly. For the first time, stage-regulated expression of the small HASPA proteins in Leishmania (Leishmania) has been demonstrated: HASPA2 is expressed only in extracellular promastigotes and HASPA1 only in intracellular amastigotes. Despite its lack of expression in amastigotes, replacement of HASPA2 into the null locus background delays onset of pathology in BALB/c mice. This HASPA2-dependent effect is reversed by HASPA1 gene addition, suggesting that the HASPAs may have a role in host immunomodulation. PMID:28095465

Effects of solution chemistry on arsenic(V) removal by low-cost adsorbents.

PubMed

Wang, Yuru; Tsang, Daniel C W

2013-11-01

Natural and anthropogenic arsenic (As) contamination of water sources pose serious health concerns, especially for small communities in rural areas. This study assessed the applicability of three industrial byproducts (coal fly ash, lignite, and green waste compost) as the low-cost adsorbents for As(V) removal under various field-relevant conditions (dissolved oxygen, As(V)/Fe ratio, solution pH, and presence of competing species). The physico-chemical properties of the adsorbents were characterized by XRD, XRF, FT-IR, and NMR analysis. Batch experiments demonstrated that coal fly ash could provide effective As(V) removal (82.1%-95%) because it contained high content of amorphous iron/aluminium hydroxides for As(V) adsorption and dissolvable calcium minerals for calcium arsenate precipitation. However, the addition of lignite and green waste compost was found unfavourable since they hindered the As(V) removal by 10%-42% possibly due to dissolution of organic matter and ternary arsenate-iron-organic matter complexes. On the other hand, higher concentrations of dissolved iron (comparing As(V)/Fe ratios of 1:1 and 1:10) and dissolved oxygen (comparing 0.2 and 6 mg/L) only marginally enhanced the As(V) removal at pH 6 and 8. Thus, addition of dissolved iron, water aeration, or pH adjustment became unnecessary because coal fly ash was able to provide effective As(V) removal under the natural range of geochemical conditions. Moreover, the presence of low levels of background competing (0.8 or 8 mg/L of humic acid, phosphate, and silicate) imposed little influence on As(V) removal, possibly because the high adsorption capacity of coal fly ash was far from exhaustion. These results suggested that coal fly ash was a potentially promising adsorbent that warranted further investigation.

Molecular genetics of aging in the fly: is this the end of the beginning?

PubMed

Helfand, Stephen L; Rogina, Blanka

2003-02-01

How we age and what we can do about it have been uppermost in human thought since antiquity. The many false starts have frustrated experimentalists and theoretical arguments pronouncing the inevitability of the process have created a nihilistic climate among scientists and the public. The identification of single gene alterations that substantially extend life span in nematodes and flies however, have begun to reinvigorate the field. Drosophila's long history of contributions to aging research, rich storehouse of genetic information, and powerful molecular techniques make it an excellent system for studying the molecular mechanisms underlying the process of aging. In recent years, Drosophila has been used to test current theories on aging and explore new directions of potential importance to the biology of aging. One such example is the surprising finding that, as opposed to the commonly held assumption that adult life is a period of random passive decline in which all things are thought to fall apart, the molecular life of the adult fly appears to be a state of dynamic well-regulated change. In the fly, the level of expression of many different genes changes in an invariant, often age-dependent, manner. These as well as other molecular genetic studies and demographic analyses using the fly have begun to challenge widely held ideas about aging providing evidence that aging may be a much more dynamic and malleable process than anticipated. With the enormous success that Drosophila molecular genetics has demonstrated in helping understand complex biological phenomena such as development there is much optimism that similar approaches can be adapted to assist in understanding the process of aging. Copyright 2003 Wiley Periodicals, Inc.

Mineralogy, chemical composition, and microstructure of ferrospheres in fly ashes from coal combustion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yongchun Zhao; Junying Zhang; Junmin Sun

2006-08-15

Fourteen samples of coal and ferrospheres, which were recovered by dry magnetic separation from fly ashes, were collected from five power plants in China. The mineralogy, chemical composition, and microstructure of ferrospheres in fly ashes have been studied by optical microscopy, X-ray diffraction (XRD), Moessbauer spectroscopy, and field emission scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (FSEM-EDX). Iron in ferrospheres mainly occurs as Fe{sub 3}O{sub 4}, {alpha}Fe{sub 2}O{sub 3}, {gamma}Fe{sub 2}O{sub 3}, MgFe{sub 2}O{sub 4}, and Fe{sup 3+}-glass, ferrian spinel, and so on. On the basis of iron content, the ferrospheres in fly ashes are classified into four groups,more » namely ferrooxides, aluminosilicate-bearing ferrooxides, high-ferriferous aluminosilicates, and ferroaluminosilicates . Ferrooxides are derived from the oxidation of iron-bearing minerals, whereas aluminosilicate-bearing ferrooxides, high-ferriferous aluminosilicates, and ferroaluminosilicates are formed by the fusion of different proportions of inherent iron-bearing minerals and clay minerals. According to their microstructure, the ferrospheres in fly ashes are classified into seven groups, namely sheet ferrospheres, dendritic ferrospheres, granular ferrospheres, smooth ferrospheres, ferroplerospheres, porous ferrospheres, and molten drop ferrospheres. Sheet ferrospheres are derived from the oxidation of iron-bearing minerals immediately; smooth ferrospheres, molten drop ferrospheres, ferroplerospheres, and porous ferrospheres are the complex eutectic of inherent iron-bearing minerals and clay minerals; dendritic ferrospheres and granular ferrospheres are formed by the conglutination after the oxidation of iron-bearing minerals. Ferrooxides and aluminosilicate-bearing ferrooxides are important sources of the initial layer that occurs in deposits formed in coal-burning systems. 78 refs., 11 figs., 4 tabs.« less

FLY MPI-2: a parallel tree code for LSS

NASA Astrophysics Data System (ADS)

Becciani, U.; Comparato, M.; Antonuccio-Delogu, V.

2006-04-01

New version program summaryProgram title: FLY 3.1 Catalogue identifier: ADSC_v2_0 Licensing provisions: yes Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADSC_v2_0 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland No. of lines in distributed program, including test data, etc.: 158 172 No. of bytes in distributed program, including test data, etc.: 4 719 953 Distribution format: tar.gz Programming language: Fortran 90, C Computer: Beowulf cluster, PC, MPP systems Operating system: Linux, Aix RAM: 100M words Catalogue identifier of previous version: ADSC_v1_0 Journal reference of previous version: Comput. Phys. Comm. 155 (2003) 159 Does the new version supersede the previous version?: yes Nature of problem: FLY is a parallel collisionless N-body code for the calculation of the gravitational force Solution method: FLY is based on the hierarchical oct-tree domain decomposition introduced by Barnes and Hut (1986) Reasons for the new version: The new version of FLY is implemented by using the MPI-2 standard: the distributed version 3.1 was developed by using the MPICH2 library on a PC Linux cluster. Today the FLY performance allows us to consider the FLY code among the most powerful parallel codes for tree N-body simulations. Another important new feature regards the availability of an interface with hydrodynamical Paramesh based codes. Simulations must follow a box large enough to accurately represent the power spectrum of fluctuations on very large scales so that we may hope to compare them meaningfully with real data. The number of particles then sets the mass resolution of the simulation, which we would like to make as fine as possible. The idea to build an interface between two codes, that have different and complementary cosmological tasks, allows us to execute complex cosmological simulations with FLY, specialized for DM evolution, and a code specialized for hydrodynamical components that uses a Paramesh block structure. Summary of revisions: The parallel communication schema was totally changed. The new version adopts the MPICH2 library. Now FLY can be executed on all Unix systems having an MPI-2 standard library. The main data structure, is declared in a module procedure of FLY (fly_h.F90 routine). FLY creates the MPI Window object for one-sided communication for all the shared arrays, with a call like the following: CALL MPI_WIN_CREATE(POS, SIZE, REAL8, MPI_INFO_NULL, MPI_COMM_WORLD, WIN_POS, IERR) the following main window objects are created: win_pos, win_vel, win_acc: particles positions velocities and accelerations, win_pos_cell, win_mass_cell, win_quad, win_subp, win_grouping: cells positions, masses, quadrupole momenta, tree structure and grouping cells. Other windows are created for dynamic load balance and global counters. Restrictions: The program uses the leapfrog integrator schema, but could be changed by the user. Unusual features: FLY uses the MPI-2 standard: the MPICH2 library on Linux systems was adopted. To run this version of FLY the working directory must be shared among all the processors that execute FLY. Additional comments: Full documentation for the program is included in the distribution in the form of a README file, a User Guide and a Reference manuscript. Running time: IBM Linux Cluster 1350, 512 nodes with 2 processors for each node and 2 GB RAM for each processor, at Cineca, was adopted to make performance tests. Processor type: Intel Xeon Pentium IV 3.0 GHz and 512 KB cache (128 nodes have Nocona processors). Internal Network: Myricom LAN Card "C" Version and "D" Version. Operating System: Linux SuSE SLES 8. The code was compiled using the mpif90 compiler version 8.1 and with basic optimization options in order to have performances that could be useful compared with other generic clusters Processors

Orientation of Colonized Sand Flies Phlebotomus papatasi, P. duboscqi, and Lutzomyia longipalpis (Diptera: Psychodidae) to Diverse Honeys Using a 3-chamber In-line Olfactometer

DTIC Science & Technology

2014-06-01

high-throughput method has utility for evaluating a diversity of natural materials with unknown complex odor blends that can then be down-selected for...method has utility for evaluating a diversity of natural materials with unknown complex odor blends that can then be down-selected for further...leishmaniasis. Lancet 366: 1561-1577. Petts, S.L., Y. Tang, and R.D. Ward. 1997. Nectar from a wax plant, Hoya sp., as a carbohydrate source for

CSAF Reading List 2013

Science.gov Websites

"Imperial Wild Eagles" of Japan and in turn won immortality as the Flying Tigers. One of --one of the first postwar films out of Hollywood to treat the war on emotionally complex terms. Framed release. Read More... Ordinance Group Loading GBU-24B Ordinance Group Loading GBU-24B by Douglas Smith

Differential Roles of the Fan-Shaped Body and the Ellipsoid Body in "Drosophila" Visual Pattern Memory

ERIC Educational Resources Information Center

Pan, Yufeng; Zhou, Yanqiong; Guo, Chao; Gong, Haiyun; Gong, Zhefeng; Liu, Li

2009-01-01

The central complex is a prominent structure in the "Drosophila" brain. Visual learning experiments in the flight simulator, with flies with genetically altered brains, revealed that two groups of horizontal neurons in one of its substructures, the fan-shaped body, were required for "Drosophila" visual pattern memory. However,…

Epigenetic Effects of Diet on Fruit Fly Lifespan: An Investigation to Teach Epigenetics to Biology Students

ERIC Educational Resources Information Center

Billingsley, James; Carlson, Kimberly A.

2010-01-01

Do our genes exclusively control us, or are other factors at play? Epigenetics can provide a means for students to use inquiry-based methods to understand a complex biological concept. Students research and design an experiment testing whether dietary supplements affect the lifespan of Drosophila melanogaster over multiple generations.

77 FR 52301 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Prince of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-29

... northern flying squirrel in the Pacific Northwest have concluded that optimal conditions for this species... Northwest, which clearly prefer complex, multi factorial habitat conditions that are characteristic of old... seeds, lichens, and fungi, all of which are more abundant in old-growth than in young-growth forests...

KSC-02pp1749

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. -- The Chickasaw Dance Troupe performs an Honor Dance during the Native American Ceremony at the Rocket Garden in the KSC Visitor Complex. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

KSC-02pp1750

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. -- The Chickasaw Dance Troupe performs an Honor Dance during the Native American Ceremony at the Rocket Garden in the KSC Visitor Complex. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

Butterflies' wings deformations using high speed digital holographic interferometry

NASA Astrophysics Data System (ADS)

Mendoza Santoyo, Fernando; Aguayo, Daniel D.; de La Torre-Ibarra, Manuel H.; Salas-Araiza, Manuel D.

2011-08-01

A variety of efforts in different scientific disciplines have tried to mimic the insect's in-flight complex system. The gained knowledge has been applied to improve the performance of different flying artifacts. In this research report it is presented a displacement measurement on butterflies' wings using the optical noninvasive Digital Holographic Interferometry technique with out of plane sensitivity, using a high power cw laser and a high speed CMOS camera to record the unrepeatable displacement movements on these organic tissues. A series of digital holographic interferograms were recorded and the experimental results for several butterflies during flapping events. The relative unwrapped phase maps micro-displacements over the whole wing surface are shown in a wire-mesh representation. The difference between flying modes is remarkably depicted among them.

Genetic basis of male sexual behavior.

PubMed

Emmons, Scott W; Lipton, Jonathan

2003-01-01

Male sexual behavior is increasingly the focus of genetic study in a variety of animals. Genetic analysis in the soil roundworm Caenorhabditis elegans and the fruit fly Drosophila melanogaster has lead to identification of genes and circuits that govern behaviors ranging from motivation and mate-searching to courtship and copulation. Some worm and fly genes have counterparts with related functions in higher animals and many more such correspondences can be expected. Analysis of mutations in mammals can potentially lead to insights into such issues as monogamous versus promiscuous sexual behavior and sexual orientation. Genetic analysis of sexual behavior has implications for understanding how the nervous system generates and controls a complex behavior. It can also help us to gain an appreciation of how behavior is encoded by genes and their regulatory sequences. Copyright 2003 Wiley Periodicals, Inc.

Automation for Accommodating Fuel-Efficient Descents in Constrained Airspace

NASA Technical Reports Server (NTRS)

Coopenbarger, Richard A.

2010-01-01

Continuous descents at low engine power are desired to reduce fuel consumption, emissions and noise during arrival operations. The challenge is to allow airplanes to fly these types of efficient descents without interruption during busy traffic conditions. During busy conditions today, airplanes are commonly forced to fly inefficient, step-down descents as airtraffic controllers work to ensure separation and maximize throughput. NASA in collaboration with government and industry partners is developing new automation to help controllers accommodate continuous descents in the presence of complex traffic and airspace constraints. This automation relies on accurate trajectory predictions to compute strategic maneuver advisories. The talk will describe the concept behind this new automation and provide an overview of the simulations and flight testing used to develop and refine its underlying technology.

Innate and intrinsic antiviral immunity in Drosophila.

PubMed

Mussabekova, Assel; Daeffler, Laurent; Imler, Jean-Luc

2017-06-01

The fruit fly Drosophila melanogaster has been a valuable model to investigate the genetic mechanisms of innate immunity. Initially focused on the resistance to bacteria and fungi, these studies have been extended to include antiviral immunity over the last decade. Like all living organisms, insects are continually exposed to viruses and have developed efficient defense mechanisms. We review here our current understanding on antiviral host defense in fruit flies. A major antiviral defense in Drosophila is RNA interference, in particular the small interfering (si) RNA pathway. In addition, complex inducible responses and restriction factors contribute to the control of infections. Some of the genes involved in these pathways have been conserved through evolution, highlighting loci that may account for susceptibility to viral infections in humans. Other genes are not conserved and represent species-specific innovations.

The PTK7-Related Transmembrane Proteins Off-track and Off-track 2 Are Co-receptors for Drosophila Wnt2 Required for Male Fertility

PubMed Central

Honemann-Capito, Mona; Brechtel-Curth, Katja; Hedderich, Marie; Wodarz, Andreas

2014-01-01

Wnt proteins regulate many developmental processes and are required for tissue homeostasis in adult animals. The cellular responses to Wnts are manifold and are determined by the respective Wnt ligand and its specific receptor complex in the plasma membrane. Wnt receptor complexes contain a member of the Frizzled family of serpentine receptors and a co-receptor, which commonly is a single-pass transmembrane protein. Vertebrate protein tyrosine kinase 7 (PTK7) was identified as a Wnt co-receptor required for control of planar cell polarity (PCP) in frogs and mice. We found that flies homozygous for a complete knock-out of the Drosophila PTK7 homolog off track (otk) are viable and fertile and do not show PCP phenotypes. We discovered an otk paralog (otk2, CG8964), which is co-expressed with otk throughout embryonic and larval development. Otk and Otk2 bind to each other and form complexes with Frizzled, Frizzled2 and Wnt2, pointing to a function as Wnt co-receptors. Flies lacking both otk and otk2 are viable but male sterile due to defective morphogenesis of the ejaculatory duct. Overexpression of Otk causes female sterility due to malformation of the oviduct, indicating that Otk and Otk2 are specifically involved in the sexually dimorphic development of the genital tract. PMID:25010066

The PTK7-related transmembrane proteins off-track and off-track 2 are co-receptors for Drosophila Wnt2 required for male fertility.

PubMed

Linnemannstöns, Karen; Ripp, Caroline; Honemann-Capito, Mona; Brechtel-Curth, Katja; Hedderich, Marie; Wodarz, Andreas

2014-07-01

Wnt proteins regulate many developmental processes and are required for tissue homeostasis in adult animals. The cellular responses to Wnts are manifold and are determined by the respective Wnt ligand and its specific receptor complex in the plasma membrane. Wnt receptor complexes contain a member of the Frizzled family of serpentine receptors and a co-receptor, which commonly is a single-pass transmembrane protein. Vertebrate protein tyrosine kinase 7 (PTK7) was identified as a Wnt co-receptor required for control of planar cell polarity (PCP) in frogs and mice. We found that flies homozygous for a complete knock-out of the Drosophila PTK7 homolog off track (otk) are viable and fertile and do not show PCP phenotypes. We discovered an otk paralog (otk2, CG8964), which is co-expressed with otk throughout embryonic and larval development. Otk and Otk2 bind to each other and form complexes with Frizzled, Frizzled2 and Wnt2, pointing to a function as Wnt co-receptors. Flies lacking both otk and otk2 are viable but male sterile due to defective morphogenesis of the ejaculatory duct. Overexpression of Otk causes female sterility due to malformation of the oviduct, indicating that Otk and Otk2 are specifically involved in the sexually dimorphic development of the genital tract.

The Gut Commensal Microbiome of Drosophila melanogaster Is Modified by the Endosymbiont Wolbachia

PubMed Central

Fast, Eva M.; Guo, Rong; Vaisman, Natalie; Ortiz, Luis; Bybee, Joanna; Slatko, Barton E.

2017-01-01

ABSTRACT Endosymbiotic Wolbachia bacteria and the gut microbiome have independently been shown to affect several aspects of insect biology, including reproduction, development, life span, stem cell activity, and resistance to human pathogens, in insect vectors. This work shows that Wolbachia bacteria, which reside mainly in the fly germline, affect the microbial species present in the fly gut in a lab-reared strain. Drosophila melanogaster hosts two main genera of commensal bacteria—Acetobacter and Lactobacillus. Wolbachia-infected flies have significantly reduced titers of Acetobacter. Sampling of the microbiome of axenic flies fed with equal proportions of both bacteria shows that the presence of Wolbachia bacteria is a significant determinant of the composition of the microbiome throughout fly development. However, this effect is host genotype dependent. To investigate the mechanism of microbiome modulation, the effect of Wolbachia bacteria on Imd and reactive oxygen species pathways, the main regulators of immune response in the fly gut, was measured. The presence of Wolbachia bacteria does not induce significant changes in the expression of the genes for the effector molecules in either pathway. Furthermore, microbiome modulation is not due to direct interaction between Wolbachia bacteria and gut microbes. Confocal analysis shows that Wolbachia bacteria are absent from the gut lumen. These results indicate that the mechanistic basis of the modulation of composition of the microbiome by Wolbachia bacteria is more complex than a direct bacterial interaction or the effect of Wolbachia bacteria on fly immunity. The findings reported here highlight the importance of considering the composition of the gut microbiome and host genetic background during Wolbachia-induced phenotypic studies and when formulating microbe-based disease vector control strategies. IMPORTANCE Wolbachia bacteria are intracellular bacteria present in the microbiome of a large fraction of insects and parasitic nematodes. They can block mosquitos’ ability to transmit several infectious disease-causing pathogens, including Zika, dengue, chikungunya, and West Nile viruses and malaria parasites. Certain extracellular bacteria present in the gut lumen of these insects can also block pathogen transmission. However, our understanding of interactions between Wolbachia and gut bacteria and how they influence each other is limited. Here we show that the presence of Wolbachia strain wMel changes the composition of gut commensal bacteria in the fruit fly. Our findings implicate interactions between bacterial species as a key factor in determining the overall composition of the microbiome and thus reveal new paradigms to consider in the development of disease control strategies. PMID:28932814

The Gut Commensal Microbiome of Drosophila melanogaster Is Modified by the Endosymbiont Wolbachia.

PubMed

Simhadri, Rama K; Fast, Eva M; Guo, Rong; Schultz, Michaela J; Vaisman, Natalie; Ortiz, Luis; Bybee, Joanna; Slatko, Barton E; Frydman, Horacio M

2017-01-01

Endosymbiotic Wolbachia bacteria and the gut microbiome have independently been shown to affect several aspects of insect biology, including reproduction, development, life span, stem cell activity, and resistance to human pathogens, in insect vectors. This work shows that Wolbachia bacteria, which reside mainly in the fly germline, affect the microbial species present in the fly gut in a lab-reared strain. Drosophila melanogaster hosts two main genera of commensal bacteria- Acetobacter and Lactobacillus . Wolbachia -infected flies have significantly reduced titers of Acetobacter . Sampling of the microbiome of axenic flies fed with equal proportions of both bacteria shows that the presence of Wolbachia bacteria is a significant determinant of the composition of the microbiome throughout fly development. However, this effect is host genotype dependent. To investigate the mechanism of microbiome modulation, the effect of Wolbachia bacteria on Imd and reactive oxygen species pathways, the main regulators of immune response in the fly gut, was measured. The presence of Wolbachia bacteria does not induce significant changes in the expression of the genes for the effector molecules in either pathway. Furthermore, microbiome modulation is not due to direct interaction between Wolbachia bacteria and gut microbes. Confocal analysis shows that Wolbachia bacteria are absent from the gut lumen. These results indicate that the mechanistic basis of the modulation of composition of the microbiome by Wolbachia bacteria is more complex than a direct bacterial interaction or the effect of Wolbachia bacteria on fly immunity. The findings reported here highlight the importance of considering the composition of the gut microbiome and host genetic background during Wolbachia -induced phenotypic studies and when formulating microbe-based disease vector control strategies. IMPORTANCE Wolbachia bacteria are intracellular bacteria present in the microbiome of a large fraction of insects and parasitic nematodes. They can block mosquitos' ability to transmit several infectious disease-causing pathogens, including Zika, dengue, chikungunya, and West Nile viruses and malaria parasites. Certain extracellular bacteria present in the gut lumen of these insects can also block pathogen transmission. However, our understanding of interactions between Wolbachia and gut bacteria and how they influence each other is limited. Here we show that the presence of Wolbachia strain w Mel changes the composition of gut commensal bacteria in the fruit fly. Our findings implicate interactions between bacterial species as a key factor in determining the overall composition of the microbiome and thus reveal new paradigms to consider in the development of disease control strategies.

Seasonal effects of wind conditions on migration patterns of soaring American white pelican.

PubMed

Gutierrez Illan, Javier; Wang, Guiming; Cunningham, Fred L; King, D Tommy

2017-01-01

Energy and time expenditures are determinants of bird migration strategies. Soaring birds have developed migration strategies to minimize these costs, optimizing the use of all the available resources to facilitate their displacement. We analysed the effects of different wind factors (tailwind, turbulence, vertical updrafts) on the migratory flying strategies adopted by 24 satellite-tracked American white pelicans (Pelecanus erythrorhynchos) throughout spring and autumn in North America. We hypothesize that different wind conditions encountered along migration routes between spring and autumn induce pelicans to adopt different flying strategies and use of these wind resources. Using quantile regression and fine-scale atmospheric data, we found that the pelicans optimized the use of available wind resources, flying faster and more direct routes in spring than in autumn. They actively selected tailwinds in both spring and autumn displacements but relied on available updrafts predominantly in their spring migration, when they needed to arrive at the breeding regions. These effects varied depending on the flying speed of the pelicans. We found significant directional correlations between the pelican migration flights and wind direction. In light of our results, we suggest plasticity of migratory flight strategies by pelicans is likely to enhance their ability to cope with the effects of ongoing climate change and the alteration of wind regimes. Here, we also demonstrate the usefulness and applicability of quantile regression techniques to investigate complex ecological processes such as variable effects of atmospheric conditions on soaring migration.

Seasonal effects of wind conditions on migration patterns of soaring American white pelican

PubMed Central

Wang, Guiming; Cunningham, Fred L.; King, D. Tommy

2017-01-01

Energy and time expenditures are determinants of bird migration strategies. Soaring birds have developed migration strategies to minimize these costs, optimizing the use of all the available resources to facilitate their displacement. We analysed the effects of different wind factors (tailwind, turbulence, vertical updrafts) on the migratory flying strategies adopted by 24 satellite-tracked American white pelicans (Pelecanus erythrorhynchos) throughout spring and autumn in North America. We hypothesize that different wind conditions encountered along migration routes between spring and autumn induce pelicans to adopt different flying strategies and use of these wind resources. Using quantile regression and fine-scale atmospheric data, we found that the pelicans optimized the use of available wind resources, flying faster and more direct routes in spring than in autumn. They actively selected tailwinds in both spring and autumn displacements but relied on available updrafts predominantly in their spring migration, when they needed to arrive at the breeding regions. These effects varied depending on the flying speed of the pelicans. We found significant directional correlations between the pelican migration flights and wind direction. In light of our results, we suggest plasticity of migratory flight strategies by pelicans is likely to enhance their ability to cope with the effects of ongoing climate change and the alteration of wind regimes. Here, we also demonstrate the usefulness and applicability of quantile regression techniques to investigate complex ecological processes such as variable effects of atmospheric conditions on soaring migration. PMID:29065188

Quantitative Assessment of Eye Phenotypes for Functional Genetic Studies Using Drosophila melanogaster

PubMed Central

Iyer, Janani; Wang, Qingyu; Le, Thanh; Pizzo, Lucilla; Grönke, Sebastian; Ambegaokar, Surendra S.; Imai, Yuzuru; Srivastava, Ashutosh; Troisí, Beatriz Llamusí; Mardon, Graeme; Artero, Ruben; Jackson, George R.; Isaacs, Adrian M.; Partridge, Linda; Lu, Bingwei; Kumar, Justin P.; Girirajan, Santhosh

2016-01-01

About two-thirds of the vital genes in the Drosophila genome are involved in eye development, making the fly eye an excellent genetic system to study cellular function and development, neurodevelopment/degeneration, and complex diseases such as cancer and diabetes. We developed a novel computational method, implemented as Flynotyper software (http://flynotyper.sourceforge.net), to quantitatively assess the morphological defects in the Drosophila eye resulting from genetic alterations affecting basic cellular and developmental processes. Flynotyper utilizes a series of image processing operations to automatically detect the fly eye and the individual ommatidium, and calculates a phenotypic score as a measure of the disorderliness of ommatidial arrangement in the fly eye. As a proof of principle, we tested our method by analyzing the defects due to eye-specific knockdown of Drosophila orthologs of 12 neurodevelopmental genes to accurately document differential sensitivities of these genes to dosage alteration. We also evaluated eye images from six independent studies assessing the effect of overexpression of repeats, candidates from peptide library screens, and modifiers of neurotoxicity and developmental processes on eye morphology, and show strong concordance with the original assessment. We further demonstrate the utility of this method by analyzing 16 modifiers of sine oculis obtained from two genome-wide deficiency screens of Drosophila and accurately quantifying the effect of its enhancers and suppressors during eye development. Our method will complement existing assays for eye phenotypes, and increase the accuracy of studies that use fly eyes for functional evaluation of genes and genetic interactions. PMID:26994292

The visual orientation memory of Drosophila requires Foraging (PKG) upstream of Ignorant (RSK2) in ring neurons of the central complex

PubMed Central

Kuntz, Sara; Poeck, Burkhard; Sokolowski, Marla B.; Strauss, Roland

2012-01-01

Orientation and navigation in a complex environment requires path planning and recall to exert goal-driven behavior. Walking Drosophila flies possess a visual orientation memory for attractive targets which is localized in the central complex of the adult brain. Here we show that this type of working memory requires the cGMP-dependent protein kinase encoded by the foraging gene in just one type of ellipsoid-body ring neurons. Moreover, genetic and epistatic interaction studies provide evidence that Foraging functions upstream of the Ignorant Ribosomal-S6 Kinase 2, thus revealing a novel neuronal signaling pathway necessary for this type of memory in Drosophila. PMID:22815538

Morphological and molecular identification of cryptic species in the Sergentomyia bailyi (Sinton, 1931) complex in Sri Lanka.

PubMed

Tharmatha, T; Gajapathy, K; Ramasamy, R; Surendran, S N

2017-02-01

The correct identification of sand fly vectors of leishmaniasis is important for controlling the disease. Genetic, particularly DNA sequence data, has lately become an important adjunct to the use of morphological criteria for this purpose. A recent DNA sequencing study revealed the presence of two cryptic species in the Sergentomyia bailyi species complex in India. The present study was undertaken to ascertain the presence of cryptic species in the Se. bailyi complex in Sri Lanka using morphological characteristics and DNA sequences from cytochrome c oxidase subunits. Sand flies were collected from leishmaniasis endemic and non-endemic dry zone districts of Sri Lanka. A total of 175 Se. bailyi specimens were initially screened for morphological variations and the identified samples formed two groups, tentatively termed as Se. bailyi species A and B, based on the relative length of the sensilla chaeticum and antennal flagellomere. DNA sequences from the mitochondrial cytochrome c oxidase subunit I (COI) and subunit II (COII) genes of morphologically identified Se. bailyi species A and B were subsequently analyzed. The two species showed differences in the COI and COII gene sequences and were placed in two separate clades by phylogenetic analysis. An allele specific polymerase chain reaction assay based on sequence variation in the COI gene accurately differentiated species A and B. The study therefore describes the first morphological and genetic evidence for the presence of two cryptic species within the Se. bailyi complex in Sri Lanka and a DNA-based laboratory technique for differentiating them.

Project of Ariane 5 LV family advancement by use of reusable fly-back boosters (named “Bargouzine”)

NASA Astrophysics Data System (ADS)

Sumin, Yu.; Bonnal, Ch.; Kostromin, S.; Panichkin, N.

2007-12-01

The paper concerns possible concept variants of a partially reusable Heavy-Lift Launch Vehicle derived from the advanced basic launcher (Ariane-2010) by means of substitution of the EAP Solid Rocket Boosters for a Reusable Starting Stage consisting two Liquid-propellant Reusable Fly-Back Boosters called "Bargouzin". This paper describes the status of the presently studied RFBB concepts during its three phases. The first project phase was dedicated to feasibility expertise of liquid-rocket reusable fly-back boosters ("Baikal" type) utilization for heavy-lift space launch vehicle. The design features and main conclusions are presented. The second phase has been performed with the purpose of selection of preferable concept among the alternative ones for the future Ariane LV modernization by using RFBB instead of EAP Boosters. The main requirements, logic of work, possible configuration and conclusion are presented. Initial aerodynamic, ballistic, thermoloading, dynamic loading, trade-off and comparison analysis have been performed on these concepts. The third phase consists in performing a more detailed expertise of the chosen LV concept. This part summarizes some of the more detailed results related to flight performance, system mass, thermoprotection system, aspects of technologies, ground complex modification, comparison analyses and conclusion.

Twilight dominates over moonlight in adjusting Drosophila's activity pattern.

PubMed

Schlichting, Matthias; Grebler, Rudi; Menegazzi, Pamela; Helfrich-Förster, Charlotte

2015-04-01

Light is the most important zeitgeber for the synchronization of the Drosophila melanogaster circadian clock. In nature, there is twilight, and the nights are rarely completely dark, a fact that is usually disregarded in lab experiments. Recent studies showed contrary effects of simulated twilight and moonlight on fly locomotor activity, with twilight shifting morning and evening activity into the day and moonlight shifting it into the night. A currently unanswered question is, what may happen to locomotor activity when flies are exposed to more natural conditions in which both moonlight and twilight are simulated? Our data demonstrate that flies are able to integrate twilight and moonlight. However, twilight seems to dominate over moonlight as both, morning and evening activity peaks, take place at dawn or at dusk, respectively, and not during the night. Furthermore, nocturnal activity decreases in the presence of twilight. The compound eyes are essential for this behavior, and by investigating different photoreceptor mutants, we unraveled the importance of photoreceptor cells 7 and 8 for wild-type phases of the activity peaks. To adjust nocturnal activity levels to a wild-type manner, all photoreceptor cells work together in a complex way, with rhodopsin 6 having a prominent role. © 2015 The Author(s).

Bumblebee flight performance in environments of different proximity.

PubMed

Linander, Nellie; Baird, Emily; Dacke, Marie

2016-02-01

Flying animals are capable of navigating through environments of different complexity with high precision. To control their flight when negotiating narrow tunnels, bees and birds use the magnitude of apparent image motion (known as optic flow) generated by the walls. In their natural habitat, however, these animals would encounter both cluttered and open environments. Here, we investigate how large changes in the proximity of nearby surfaces affect optic flow-based flight control strategies. We trained bumblebees to fly along a flight and recorded how the distance between the walls--from 60 cm to 240 cm--affected their flight control. Our results reveal that, as tunnel width increases, both lateral position and ground speed become increasingly variable. We also find that optic flow information from the ground has an increasing influence on flight control, suggesting that bumblebees measure optic flow flexibly over a large lateral and ventral field of view, depending on where the highest magnitude of optic flow occurs. A consequence of this strategy is that, when flying in narrow spaces, bumblebees use optic flow information from the nearby obstacles to control flight, while in more open spaces they rely primarily on optic flow cues from the ground.

Floral volatiles in a sapromyiophilous plant and their importance in attracting house fly pollinators.

PubMed

Zito, Pietro; Dötterl, Stefan; Sajeva, Maurizio

2015-04-01

Floral scent in sapromyiophilous plants often consists of complex blends with not only fetid (e.g., sulfides) but also sweet (e.g., terpenoids) volatile organic compounds, and a recent study suggests that both groups of compounds are involved in pollinator attraction. However, little is known about the number and identity of compounds involved in pollinator attraction in these deceptive plants that mimic breeding sites of fly pollinators. In the present paper, we studied flower volatiles of sapromyiophilous Periploca laevigata and their capability to elicit biological responses in one of the pollinator species, Musca domestica. Floral volatiles were collected by dynamic headspace and analyzed by gas chromatography/mass spectrometry (GC/MS), and electrophysiological (GC/EAD) and behavioral assays (two choice olfactometer) were conducted. In the floral scent of P. laevigata, we detected 44 compounds, of which indole, β-caryophyllene, and germacrene D, as well as dimethyl trisulfide, which was present in trace amounts, were electrophysiologically active in the antennae of M. domestica. However, when we evaluated in behavioral experiments the attractiveness of the electrophysiologically active compounds (complete mixture against partial mixtures or against single compounds), we found that indole was the only attractive compound for the flies.

The legal implications of preflight medical screening of civil airline passengers.

PubMed

Newson-Smith, M S

1997-10-01

It has been suggested that meticulous preflight medical screening of airline passengers would prevent most in-flight medical emergencies and it has been estimated that medical assistance is sought on around 1 in 50 international flights on wide bodied domestic aircraft. It was considered that the legal implications of such screening needed to be determined. A literature review of current legislation, court cases, and legal and medical journals was conducted. It was found that the legal problems with preflight medical screening fell into three areas: discrimination, right to free movement, and guidelines to medical contraindications to flying. It was considered that precluding someone from flying on medical grounds could in certain circumstances be construed as discriminatory or a breach of the basic human right of freedom of movement and, thus, unlawful. Current guidelines on medical contraindications to flying vary and there are presently no internationally agreed or legally enforceable protocols on the subject. Pre-flight medical screening of civil airline passengers may offer a means of reducing in-flight morbidity, but the complexity of the legal issues involved are such that it is unlikely to be introduced in the near future.

Modifiers and mechanisms of multi-system polyglutamine neurodegenerative disorders: lessons from fly models.

PubMed

Mallik, Moushami; Lakhotia, Subhash C

2010-12-01

Polyglutamine (polyQ) diseases, resulting from a dynamic expansion of glutamine repeats in a polypeptide, are a class of genetically inherited late onset neurodegenerative disorders which, despite expression of the mutated gene widely in brain and other tissues, affect defined subpopulations of neurons in a disease-specific manner. We briefly review the different polyQ-expansion-induced neurodegenerative disorders and the advantages of modelling them in Drosophila. Studies using the fly models have successfully identified a variety of genetic modifiers and have helped in understanding some of the molecular events that follow expression of the abnormal polyQ proteins. Expression of the mutant polyQ proteins causes, as a consequence of intra-cellular and inter-cellular networking, mis-regulation at multiple steps like transcriptional and posttranscriptional regulations, cell signalling, protein quality control systems (protein folding and degradation networks), axonal transport machinery etc., in the sensitive neurons, resulting ultimately in their death. The diversity of genetic modifiers of polyQ toxicity identified through extensive genetic screens in fly and other models clearly reflects a complex network effect of the presence of the mutated protein. Such network effects pose a major challenge for therapeutic applications.

Reconfigurable Software for Controlling Formation Flying

NASA Technical Reports Server (NTRS)

Mueller, Joseph B.

2006-01-01

Software for a system to control the trajectories of multiple spacecraft flying in formation is being developed to reflect underlying concepts of (1) a decentralized approach to guidance and control and (2) reconfigurability of the control system, including reconfigurability of the software and of control laws. The software is organized as a modular network of software tasks. The computational load for both determining relative trajectories and planning maneuvers is shared equally among all spacecraft in a cluster. The flexibility and robustness of the software are apparent in the fact that tasks can be added, removed, or replaced during flight. In a computational simulation of a representative formation-flying scenario, it was demonstrated that the following are among the services performed by the software: Uploading of commands from a ground station and distribution of the commands among the spacecraft, Autonomous initiation and reconfiguration of formations, Autonomous formation of teams through negotiations among the spacecraft, Working out details of high-level commands (e.g., shapes and sizes of geometrically complex formations), Implementation of a distributed guidance law providing autonomous optimization and assignment of target states, and Implementation of a decentralized, fuel-optimal, impulsive control law for planning maneuvers.

When Poetry became Ethnography and Other Flying Pig Tales in Honor of Dell Hymes

ERIC Educational Resources Information Center

Cahnmann-Taylor, Melisa

2011-01-01

Cahnmann-Taylor remembers her first encounter with Dell Hymes at an open mic event at the annual meeting of the American Anthropological Association. She puzzles his complex stance on the role ethnographic poems might play in one's ethnographic project. In Dell Hymes's honor, she shares a poetic rendering of a speech event from her bilingual…

KSC-02pp1757

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. -- Singer Buffy Sainte-Marie sings during a pre-launch Native American ceremony in the Rocket Garden of the KSC Visitor Complex. She herself is a Cree. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

KSC-02pp1753

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. -- Chickasaw Tribal Elder Lee Frazier leads the dedication to the astronauts of STS-113 during the Native American Ceremony at the Rocket Garden in the KSC Visitor Complex. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

KSC-02pp1727

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. -- Chickasaw Indian princesses pose with folk singer Buffy Saint- Marie (center) during a Native American ceremony held in the Rocket Garden in the KSC Visitor Complex. Several days of activities were held at KSC and in Orlando commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

KSC-02pp1751

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. -- The Chickasaw Dance Troupe performs an Honor Dance for John Herrington's parents during the Native American Ceremony at the Rocket Garden in the KSC Visitor Complex. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

KSC-02pp1758

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. -- Singer Buffy Sainte-Marie sings during a pre-launch Native American ceremony in the Rocket Garden of the KSC Visitor Complex. She herself is a Cree. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

KSC-02pp1742

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. -- Chickasaw Indian princesses seen here contributed to a pre-launch Native American ceremony at the Rocket Garden in the KSC Visitor Complex by leading a prayer. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

KSC-02pp1752

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. - Chickasaw Dance troupe member Tim Harjo (second from left) leads Joyce and James Herrington in a dance honoring their son, STS-113 Mission Specialist John Herrington. The dance was part of a Native American ceremony at the Rocket Garden in the KSC Visitor Complex commemorating Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission.

Physics-Based Design of Micro Air Vehicles

DTIC Science & Technology

2012-04-01

7   Figure 5. Comparison of an insect wing and a manufactured wing for a flapping MAV. .............. 8...topologies for a flapping-wing compliant actuation mechanism. Hatched areas are clamped. Cases 1-3 have fixed supports; cases 4 and 5 have variable...world by flying insects , birds, and mammals. However, an inadequate understanding of the complex, nonlinear, and multidisciplinary physics that

Leveraging Simulation Against the F-16 Flying Training Gap

DTIC Science & Technology

2005-11-01

must leverage emerging simulation technology into combined flight training to counter mission employment complexity created by technology itself...two or more of these stand-alone simulators creates a mission training center (MTC), which when further networked create distributed mission...operations (DMO). Ultimately, the grand operational vision of DMO is to interconnect non-collocated users creating a “virtual” joint training environment

Great horned owls are released at CCAFS

NASA Technical Reports Server (NTRS)

2000-01-01

A great horned owl flies to freedom after its release at Cape Canaveral Air Force Station, Complex 25/29. The owl is one of two found in June on the floor of CCAFS Hangar G, where their nest was located. They were treated at a local veterinary hospital and then taken to the Florida Wildlife Hospital in Melbourne for care and rehabilitation before release.

Synonymization of key pest species within the Bactrocera dorsalis species complex (Diptera: Tephritidae): taxonomic changes based on a review of 20 years of integrative morphological, molecular, cytogenetic, behavioral, and c

USDA-ARS?s Scientific Manuscript database

Bactrocera papayae Drew & Hancock, Bactrocera philippinensis Drew & Hancock, Bactrocera carambolae Drew & Hancock, and Bactrocera invadens Drew, Tsuruta & White are four horticultural pest tephritid fruit fly species that are highly morphologically and genetically similar to the destructive pest, th...

KSC-00pp0968

NASA Image and Video Library

2000-06-07

A great horned owl flies to freedom after its release at Cape Canaveral Air Force Station, Complex 25/29. The owl is one of two found in June on the floor of CCAFS Hangar G, where their nest was located. They were treated at a local veterinary hospital and then taken to the Florida Wildlife Hospital in Melbourne for care and rehabilitation before release

KSC00pp0968

NASA Image and Video Library

2000-06-07

A great horned owl flies to freedom after its release at Cape Canaveral Air Force Station, Complex 25/29. The owl is one of two found in June on the floor of CCAFS Hangar G, where their nest was located. They were treated at a local veterinary hospital and then taken to the Florida Wildlife Hospital in Melbourne for care and rehabilitation before release

Neuropeptide Mapping of Dimmed Cells of Adult Drosophila Brain

NASA Astrophysics Data System (ADS)

Diesner, Max; Predel, Reinhard; Neupert, Susanne

2018-05-01

Neuropeptides are structurally highly diverse messenger molecules that act as regulators of many physiological processes such as development, metabolism, reproduction or behavior in general. Differentiation of neuropeptidergic cells often corresponds with the presence of the transcription factor DIMMED. In the central nervous system of the fruit fly Drosophila melanogaster, DIMMED commonly occurs in neuroendocrine neurons that release peptides as neurohormones but also in interneurons with complex branching patterns. Fly strains with green fluorescence protein (GFP)-expressing dimmed cells make it possible to systematically analyze the processed neuropeptides in these cells. In this study, we mapped individual GFP-expressing neurons of adult D. melanogaster from the dimmed ( c929)>GFP line. Using single cell mass spectrometry, we analyzed 10 types of dimmed neurons from the brain/gnathal ganglion. These cells included neuroendocrine cells with projection into the retrocerebral complex but also a number of large interneurons. Resulting mass spectra not only provided comprehensive data regarding mature products from 13 neuropeptide precursors but also evidence for the cellular co-localization of neuropeptides from different neuropeptide genes. The results can be implemented in a neuroanatomical map of the D. melanogaster brain. [Figure not available: see fulltext.

Germanium recovery from gasification fly ash: evaluation of end-products obtained by precipitation methods.

PubMed

Arroyo, Fátima; Font, Oriol; Fernández-Pereira, Constantino; Querol, Xavier; Juan, Roberto; Ruiz, Carmen; Coca, Pilar

2009-08-15

In this study the purity of the germanium end-products obtained by two different precipitation methods carried out on germanium-bearing solutions was evaluated as a last step of a hydrometallurgy process for the recovery of this valuable element from the Puertollano Integrated Gasification Combined Cycle (IGCC) fly ash. Since H(2)S is produced as a by-product in the gas cleaning system of the Puertollano IGCC plant, precipitation of germanium as GeS(2) was tested by sulfiding the Ge-bearing solutions. The technological and hazardous issues that surround H(2)S handling conducted to investigate a novel precipitation procedure: precipitation as an organic complex by adding 1,2-dihydroxy benzene pyrocatechol (CAT) and cetyltrimethylammonium bromide (CTAB) to the Ge-bearing solutions. Relatively high purity Ge end-products (90 and 93% hexagonal-GeO(2) purity, respectively) were obtained by precipitating Ge from enriched solutions, as GeS(2) sulfiding the solutions with H(2)S, or as organic complex with CAT/CTAB mixtures and subsequent roasting of the precipitates. Both methods showed high efficiency (>99%) to precipitate selectively Ge using a single precipitation stage from germanium-bearing solutions.

KENNEDY SPACE CENTER, FLA. - NASA T-38 jets fly over the Space Mirror Memorial at the Kennedy Space Center Visitor Complex in the Missing Man Formation. During this dedication ceremony, the names of the STS-107 astronauts who lost their lives during the Columbia accident -- Rick Husband, Willie McCool, Laurel Clark, Michael Anderson, David Brown, Kalpana Chawla, and Ilan Ramon -- join the names of 17 other space heroes who gave their lives for the U.S. space program. The "Space Mirror," 42 1/2 feet high by 50 feet wide, illuminates the names of the fallen astronauts cut through the monument's black granite surface.

NASA Image and Video Library

2003-10-28

KENNEDY SPACE CENTER, FLA. - NASA T-38 jets fly over the Space Mirror Memorial at the Kennedy Space Center Visitor Complex in the Missing Man Formation. During this dedication ceremony, the names of the STS-107 astronauts who lost their lives during the Columbia accident -- Rick Husband, Willie McCool, Laurel Clark, Michael Anderson, David Brown, Kalpana Chawla, and Ilan Ramon -- join the names of 17 other space heroes who gave their lives for the U.S. space program. The "Space Mirror," 42 1/2 feet high by 50 feet wide, illuminates the names of the fallen astronauts cut through the monument's black granite surface.

Neuropeptide Mapping of Dimmed Cells of Adult Drosophila Brain

NASA Astrophysics Data System (ADS)

Diesner, Max; Predel, Reinhard; Neupert, Susanne

2018-01-01

Neuropeptides are structurally highly diverse messenger molecules that act as regulators of many physiological processes such as development, metabolism, reproduction or behavior in general. Differentiation of neuropeptidergic cells often corresponds with the presence of the transcription factor DIMMED. In the central nervous system of the fruit fly Drosophila melanogaster, DIMMED commonly occurs in neuroendocrine neurons that release peptides as neurohormones but also in interneurons with complex branching patterns. Fly strains with green fluorescence protein (GFP)-expressing dimmed cells make it possible to systematically analyze the processed neuropeptides in these cells. In this study, we mapped individual GFP-expressing neurons of adult D. melanogaster from the dimmed (c929)>GFP line. Using single cell mass spectrometry, we analyzed 10 types of dimmed neurons from the brain/gnathal ganglion. These cells included neuroendocrine cells with projection into the retrocerebral complex but also a number of large interneurons. Resulting mass spectra not only provided comprehensive data regarding mature products from 13 neuropeptide precursors but also evidence for the cellular co-localization of neuropeptides from different neuropeptide genes. The results can be implemented in a neuroanatomical map of the D. melanogaster brain. [Figure not available: see fulltext.

Agent Based Software for the Autonomous Control of Formation Flying Spacecraft

NASA Technical Reports Server (NTRS)

How, Jonathan P.; Campbell, Mark; Dennehy, Neil (Technical Monitor)

2003-01-01

Distributed satellite systems is an enabling technology for many future NASA/DoD earth and space science missions, such as MMS, MAXIM, Leonardo, and LISA [1, 2, 3]. While formation flying offers significant science benefits, to reduce the operating costs for these missions it will be essential that these multiple vehicles effectively act as a single spacecraft by performing coordinated observations. Autonomous guidance, navigation, and control as part of a coordinated fleet-autonomy is a key technology that will help accomplish this complex goal. This is no small task, as most current space missions require significant input from the ground for even relatively simple decisions such as thruster burns. Work for the NMP DS1 mission focused on the development of the New Millennium Remote Agent (NMRA) architecture for autonomous spacecraft control systems. NMRA integrates traditional real-time monitoring and control with components for constraint-based planning, robust multi-threaded execution, and model-based diagnosis and reconfiguration. The complexity of using an autonomous approach for space flight software was evident when most of its capabilities were stripped off prior to launch (although more capability was uplinked subsequently, and the resulting demonstration was very successful).

Neuropeptide Mapping of Dimmed Cells of Adult Drosophila Brain.

PubMed

Diesner, Max; Predel, Reinhard; Neupert, Susanne

2018-05-01

Neuropeptides are structurally highly diverse messenger molecules that act as regulators of many physiological processes such as development, metabolism, reproduction or behavior in general. Differentiation of neuropeptidergic cells often corresponds with the presence of the transcription factor DIMMED. In the central nervous system of the fruit fly Drosophila melanogaster, DIMMED commonly occurs in neuroendocrine neurons that release peptides as neurohormones but also in interneurons with complex branching patterns. Fly strains with green fluorescence protein (GFP)-expressing dimmed cells make it possible to systematically analyze the processed neuropeptides in these cells. In this study, we mapped individual GFP-expressing neurons of adult D. melanogaster from the dimmed (c929)>GFP line. Using single cell mass spectrometry, we analyzed 10 types of dimmed neurons from the brain/gnathal ganglion. These cells included neuroendocrine cells with projection into the retrocerebral complex but also a number of large interneurons. Resulting mass spectra not only provided comprehensive data regarding mature products from 13 neuropeptide precursors but also evidence for the cellular co-localization of neuropeptides from different neuropeptide genes. The results can be implemented in a neuroanatomical map of the D. melanogaster brain. Graphical Abstract ᅟ.

Cognitive Performance Effects of Bilastine 20 mg During 6 Hours at 8000 ft Cabin Altitude.

PubMed

Valk, Pierre J L; Simons, Ries; Jetten, Andrea M; Valiente, Román; Labeaga, Luis

2016-07-01

Bilastine is a new oral, second generation antihistamine used in the symptomatic treatment of allergic rhinoconjunctivitis and urticaria. It is considered a nonsedating antihistamine and might be recommended for use in pilots, pending research on the effects on flying-related performance under hypobaric conditions that prevail in an airliner. We assessed the effects of a single dose of bilastine 20 mg on alertness and complex task performance of healthy volunteers in a hypobaric chamber at 75.2 kPa (8000 ft/2438 m cabin altitude). In a randomized, double-blind, crossover study, 24 volunteers received a single dose of bilastine 20 mg, hydroxyzine 50 mg (active control), and placebo. Using the Vigilance and Tracking Task, Multi-Attribute Task Battery, and Stanford Sleepiness Scale, assessments were made before and up to 6 h after intake of the study medication. Bilastine 20 mg had no impairing effects on sleepiness levels, vigilance, or complex task performance for up to 6 h post-dose. Hydroxyzine 50 mg (active control) was associated with significant sleepiness and impaired performance across this time period, confirming the sensitivity of the tests. Bilastine 20 mg did not cause sleepiness or impaired performance on tasks related to flying. It is anticipated that a single dose of bilastine 20 mg will not affect flying performance. Bilastine may provide a safe therapeutic alternative for pilots suffering from allergic rhinitis or urticaria. Our findings might also have implications for the treatment of allergic disorders of personnel involved in other safety-sensitive jobs. Valk PJL, Simons R, Jetten AM, Valiente R, Labeaga L. Cognitive performance effects of bilastine 20 mg during 6 hours at 8000 ft cabin altitude. Aerosp Med Hum Perform. 2016; 87(7):622-627.

Falling with Style: Bats Perform Complex Aerial Rotations by Adjusting Wing Inertia.

PubMed

Bergou, Attila J; Swartz, Sharon M; Vejdani, Hamid; Riskin, Daniel K; Reimnitz, Lauren; Taubin, Gabriel; Breuer, Kenneth S

2015-01-01

The remarkable maneuverability of flying animals results from precise movements of their highly specialized wings. Bats have evolved an impressive capacity to control their flight, in large part due to their ability to modulate wing shape, area, and angle of attack through many independently controlled joints. Bat wings, however, also contain many bones and relatively large muscles, and thus the ratio of bats' wing mass to their body mass is larger than it is for all other extant flyers. Although the inertia in bat wings would typically be associated with decreased aerial maneuverability, we show that bat maneuvers challenge this notion. We use a model-based tracking algorithm to measure the wing and body kinematics of bats performing complex aerial rotations. Using a minimal model of a bat with only six degrees of kinematic freedom, we show that bats can perform body rolls by selectively retracting one wing during the flapping cycle. We also show that this maneuver does not rely on aerodynamic forces, and furthermore that a fruit fly, with nearly massless wings, would not exhibit this effect. Similar results are shown for a pitching maneuver. Finally, we combine high-resolution kinematics of wing and body movements during landing and falling maneuvers with a 52-degree-of-freedom dynamical model of a bat to show that modulation of wing inertia plays the dominant role in reorienting the bat during landing and falling maneuvers, with minimal contribution from aerodynamic forces. Bats can, therefore, use their wings as multifunctional organs, capable of sophisticated aerodynamic and inertial dynamics not previously observed in other flying animals. This may also have implications for the control of aerial robotic vehicles.

Experiments in cooperative-arm object manipulation with a two-armed free-flying robot. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Koningstein, Ross

1990-01-01

Developing computed-torque controllers for complex manipulator systems using current techniques and tools is difficult because they address the issues pertinent to simulation, as opposed to control. A new formulation of computed-torque (CT) control that leads to an automated computer-torque robot controller program is presented. This automated tool is used for simulations and experimental demonstrations of endpoint and object control from a free-flying robot. A new computed-torque formulation states the multibody control problem in an elegant, homogeneous, and practical form. A recursive dynamics algorithm is presented that numerically evaluates kinematics and dynamics terms for multibody systems given a topological description. Manipulators may be free-flying, and may have closed-chain constraints. With the exception of object squeeze-force control, the algorithm does not deal with actuator redundancy. The algorithm is used to implement an automated 2D computed-torque dynamics and control package that allows joint, endpoint, orientation, momentum, and object squeeze-force control. This package obviates the need for hand-derivation of kinematics and dynamics, and is used for both simulation and experimental control. Endpoint control experiments are performed on a laboratory robot that has two arms to manipulate payloads, and uses an air bearing to achieve very-low drag characteristics. Simulations and experimental data for endpoint and object controllers are presented for the experimental robot - a complex dynamic system. There is a certain rather wide set of conditions under which CT endpoint controllers can neglect robot base accelerations (but not motions) and achieve comparable performance including base accelerations in the model. The regime over which this simplification holds is explored by simulation and experiment.

Sm protein methylation is dispensable for snRNP assembly in Drosophila melanogaster.

PubMed

Gonsalvez, Graydon B; Praveen, Kavita; Hicks, Amanda J; Tian, Liping; Matera, A Gregory

2008-05-01

Sm proteins form stable ribonucleoprotein (RNP) complexes with small nuclear (sn)RNAs and are core components of the eukaryotic spliceosome. In vivo, the assembly of Sm proteins onto snRNAs requires the survival motor neurons (SMN) complex. Several reports have shown that SMN protein binds with high affinity to symmetric dimethylarginine (sDMA) residues present on the C-terminal tails of SmB, SmD1, and SmD3. This post-translational modification is thought to play a crucial role in snRNP assembly. In human cells, two distinct protein arginine methyltransferases (PRMT5 and PRMT7) are required for snRNP biogenesis. However, in Drosophila, loss of Dart5 (the fruit fly PRMT5 ortholog) has little effect on snRNP assembly, and homozygous mutants are completely viable. To resolve these apparent differences, we examined this topic in detail and found that Drosophila Sm proteins are also methylated by two methyltransferases, Dart5/PRMT5 and Dart7/PRMT7. Unlike dart5, we found that dart7 is an essential gene. However, the lethality associated with loss of Dart7 protein is apparently unrelated to defects in snRNP assembly. To conclusively test the requirement for sDMA modification of Sm proteins in Drosophila snRNP assembly, we constructed a fly strain that exclusively expresses an isoform of SmD1 that cannot be sDMA modified. Interestingly, these flies were viable, and snRNP assays revealed no defects in comparison to wild type. In contrast, dart5 mutants displayed a strong synthetic lethal phenotype in the presence of a hypomorphic Smn mutation. We therefore conclude that dart5 is required for viability when SMN is limiting.

Modeling Drosophila Positional Preferences in Open Field Arenas with Directional Persistence and Wall Attraction

PubMed Central

Soibam, Benjamin; Goldfeder, Rachel L.; Manson-Bishop, Claire; Gamblin, Rachel; Pletcher, Scott D.; Shah, Shishir; Gunaratne, Gemunu H.; Roman, Gregg W.

2012-01-01

In open field arenas, Drosophila adults exhibit a preference for arena boundaries over internal walls and open regions. Herein, we investigate the nature of this preference using phenomenological modeling of locomotion to determine whether local arena features and constraints on movement alone are sufficient to drive positional preferences within open field arenas of different shapes and with different internal features. Our model has two components: directional persistence and local wall force. In regions far away from walls, the trajectory is entirely characterized by a directional persistence probability, , for each movement defined by the step size, , and the turn angle, . In close proximity to walls, motion is computed from and a local attractive force which depends on the distance between the fly and points on the walls. The directional persistence probability was obtained experimentally from trajectories of wild type Drosophila in a circular open field arena and the wall force was computed to minimize the difference between the radial distributions from the model and Drosophila in the same circular arena. The two-component model for fly movement was challenged by comparing the positional preferences from the two-component model to wild type Drosophila in a variety of open field arenas. In most arenas there was a strong concordance between the two-component model and Drosophila. In more complex arenas, the model exhibits similar trends, but some significant differences were found. These differences suggest that there are emergent features within these complex arenas that have significance for the fly, such as potential shelter. Hence, the two-component model is an important step in defining how Drosophila interact with their environment. PMID:23071591

Falling with Style: Bats Perform Complex Aerial Rotations by Adjusting Wing Inertia

PubMed Central

Bergou, Attila J.; Swartz, Sharon M.; Vejdani, Hamid; Riskin, Daniel K.; Reimnitz, Lauren; Taubin, Gabriel; Breuer, Kenneth S.

2015-01-01

The remarkable maneuverability of flying animals results from precise movements of their highly specialized wings. Bats have evolved an impressive capacity to control their flight, in large part due to their ability to modulate wing shape, area, and angle of attack through many independently controlled joints. Bat wings, however, also contain many bones and relatively large muscles, and thus the ratio of bats’ wing mass to their body mass is larger than it is for all other extant flyers. Although the inertia in bat wings would typically be associated with decreased aerial maneuverability, we show that bat maneuvers challenge this notion. We use a model-based tracking algorithm to measure the wing and body kinematics of bats performing complex aerial rotations. Using a minimal model of a bat with only six degrees of kinematic freedom, we show that bats can perform body rolls by selectively retracting one wing during the flapping cycle. We also show that this maneuver does not rely on aerodynamic forces, and furthermore that a fruit fly, with nearly massless wings, would not exhibit this effect. Similar results are shown for a pitching maneuver. Finally, we combine high-resolution kinematics of wing and body movements during landing and falling maneuvers with a 52-degree-of-freedom dynamical model of a bat to show that modulation of wing inertia plays the dominant role in reorienting the bat during landing and falling maneuvers, with minimal contribution from aerodynamic forces. Bats can, therefore, use their wings as multifunctional organs, capable of sophisticated aerodynamic and inertial dynamics not previously observed in other flying animals. This may also have implications for the control of aerial robotic vehicles. PMID:26569116

Low-speed longitudinal orbiter qualities

NASA Technical Reports Server (NTRS)

Powers, B. G.

1985-01-01

The shuttle program took on the challenge of providing a manual landing capability for an operational vehicle returning from orbit. Some complex challenges were encountered in developing the longitudinal flying qualities required to land the orbiter manually in an operational environment. Approach and landing test flights indicated a tendency for pilot-induced oscillation near landing. Changes in the operational procedures reduced the difficulty of the landing task, and an adaptive stick filter was incorporated to reduce the severity of any pilot-induced oscillatory motions. Fixed-base, movingbase, and in-flight simulations were used for the evaluations, and in general, flight simulation was the only reliable means of assessing the low-speed longitudinal flying qualities problems. Overall, the orbiter control system and operational procedures have produced a good capability to routinely perform precise landings with a large, unpowered vehicle with a low lift-to-drag ratio.

Quantifying and predicting Drosophila larvae crawling phenotypes

NASA Astrophysics Data System (ADS)

Günther, Maximilian N.; Nettesheim, Guilherme; Shubeita, George T.

2016-06-01

The fruit fly Drosophila melanogaster is a widely used model for cell biology, development, disease, and neuroscience. The fly’s power as a genetic model for disease and neuroscience can be augmented by a quantitative description of its behavior. Here we show that we can accurately account for the complex and unique crawling patterns exhibited by individual Drosophila larvae using a small set of four parameters obtained from the trajectories of a few crawling larvae. The values of these parameters change for larvae from different genetic mutants, as we demonstrate for fly models of Alzheimer’s disease and the Fragile X syndrome, allowing applications such as genetic or drug screens. Using the quantitative model of larval crawling developed here we use the mutant-specific parameters to robustly simulate larval crawling, which allows estimating the feasibility of laborious experimental assays and aids in their design.

ATP-dependent human RISC assembly pathways.

PubMed

Yoda, Mayuko; Kawamata, Tomoko; Paroo, Zain; Ye, Xuecheng; Iwasaki, Shintaro; Liu, Qinghua; Tomari, Yukihide

2010-01-01

The assembly of RNA-induced silencing complex (RISC) is a key process in small RNA-mediated gene silencing. In humans, small interfering RNAs (siRNAs) and microRNAs (miRNAs) are incorporated into RISCs containing the Argonaute (AGO) subfamily proteins Ago1-4. Previous studies have proposed that, unlike Drosophila melanogaster RISC assembly pathways, human RISC assembly is coupled with dicing and is independent of ATP. Here we show by careful reexamination that, in humans, RISC assembly and dicing are uncoupled, and ATP greatly facilitates RISC loading of small-RNA duplexes. Moreover, all four human AGO proteins show remarkably similar structural preferences for small-RNA duplexes: central mismatches promote RISC loading, and seed or 3'-mid (guide position 12-15) mismatches facilitate unwinding. All these features of human AGO proteins are highly reminiscent of fly Ago1 but not fly Ago2.

Beetle wings are inflatable origami

NASA Astrophysics Data System (ADS)

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

2015-11-01

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

Drosophila melanogaster: a fly through its history and current use.

PubMed

Stephenson, R; Metcalfe, N H

2013-01-01

Drosophila melanogaster, the common fruit fly, has been used as a model organism in both medical and scientific research for over a century. Work by Thomas Hunt Morgan (1866-1945) and his students at Columbia University at the beginning of the twentieth century led to great discoveries such as sex-linked inheritance and that ionising radiation causes mutations in genes. However, the use of Drosophila was not limited to genetic research. Experimentation with this model organism has also led to discoveries in neuroscience and neurodevelopment, including the basis of circadian rhythms. Its complex nervous system, conserved neurological function, and human disease-related loci allow Drosophila to be an ideal model organism for the study of neurodegenerative disease, for which it is used today, aiding research into diseases such as Alzheimer's and Parkinson's, which are becoming more prevalent in today's ageing population.

FliO Regulation of FliP in the Formation of the Salmonella enterica Flagellum

PubMed Central

Barker, Clive S.; Meshcheryakova, Irina V.; Kostyukova, Alla S.; Samatey, Fadel A.

2010-01-01

The type III secretion system of the Salmonella flagellum consists of 6 integral membrane proteins: FlhA, FlhB, FliO, FliP, FliQ, and FliR. However, in some other type III secretion systems, a homologue of FliO is apparently absent, suggesting it has a specialized role. Deleting the fliO gene from the chromosome of a motile strain of Salmonella resulted in a drastic decrease of motility. Incubation of the ΔfliO mutant strain in motility agar, gave rise to pseudorevertants containing extragenic bypass mutations in FliP at positions R143H or F190L. Using membrane topology prediction programs, and alkaline phosphatase or GFPuv chimeric protein fusions into the FliO protein, we demonstrated that FliO is bitopic with its N-terminus in the periplasm and C-terminus in the cytoplasm. Truncation analysis of FliO demonstrated that overexpression of FliO43–125 or FliO1–95 was able to rescue motility of the ΔfliO mutant. Further, residue leucine 91 in the cytoplasmic domain was identified to be important for function. Based on secondary structure prediction, the cytoplasmic domain, FliO43–125, should contain beta-structure and alpha-helices. FliO43–125-Ala was purified and studied using circular dichroism spectroscopy; however, this domain was disordered, and its structure was a mixture of beta-sheet and random coil. Coexpression of full-length FliO with FliP increased expression levels of FliP, but coexpression with the cytoplasmic domain of FliO did not enhance FliP expression levels. Overexpression of the cytoplasmic domain of FliO further rescued motility of strains deleted for the fliO gene expressing bypass mutations in FliP. These results suggest FliO maintains FliP stability through transmembrane domain interaction. The results also demonstrate that the cytoplasmic domain of FliO has functionality, and it presumably becomes structured while interacting with its binding partners. PMID:20941389

KSC-2012-1121

NASA Image and Video Library

2012-01-26

CAPE CANAVERAL, Fla. -- An American flag flies at half staff near the Space Mirror Memorial at the Kennedy Space Center Visitor Complex in Florida during Kennedy Space Center’s NASA Day of Remembrance. The Day of Remembrance honors members of the NASA family who lost their lives while furthering the cause of exploration and discovery, including the astronaut crews of Apollo 1 and space shuttles Challenger and Columbia. Kennedy civil service and contractor employees, along with the general public, paid their respects throughout the day. The visitor complex provided flowers for visitors to place at the memorial. Photo credit: NASA/Kim Shiflett

MARINER 10 LAUNCH VEHICLE ATLAS CENTAUR 34 UNDERGOES TANKING TEST AT LAUNCH COMPLEX 36B

NASA Technical Reports Server (NTRS)

1973-01-01

Atlas Centaur 34, undergoes tanking test on NASA Complex 36B at Cape Kennedy, Fla. Atlas Centaur 34 is under preparation to launch history's first duel-planet flight, the Mariner mission to Venus and Mercury, scheduled for early November. With all events going as planned, the Mariner spacecraft will fly by Venus in early February, 1974, and reach Mercury in late march, 1974. The spacecraft, Mariner 10, will carry two television cameras to photograph the planets, and six other scientific experiments to return planetary and interplanetary data back to Earth.

7 CFR 301.32-1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... fly (fruit flies). The melon fruit fly, Mexican fruit fly, Mediterranean fruit fly, Oriental fruit fly..., Ceratitis capitata (Wiedemann), in any stage of development. Melon fruit fly. The insect known as the melon...

7 CFR 301.32-1 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... fly (fruit flies). The melon fruit fly, Mexican fruit fly, Mediterranean fruit fly, Oriental fruit fly..., Ceratitis capitata (Wiedemann), in any stage of development. Melon fruit fly. The insect known as the melon...

Stable fly, house fly (Diptera: Muscidae), and other nuisance fly development in poultry litter associated with horticultural crop production.

PubMed

Cook, D F; Dadour, I R; Keals, N J

1999-12-01

Poultry litter usage in horticultural crop production is a contributor to nuisance fly populations, in particular stable flies (Stomoxys calcitrans L.) and house flies (Musca domestica L.). Extrapolation of adult emergence data suggests that approximately 1.5 million house flies and 0.2 million stable flies are emerging on average from every hectare of poultry litter applied as a preplant fertilizer for vegetable production in Perth, Western Australia. To a lesser extent, sideband applications to established crops may allow for the development of 0.5 million house flies and 45,000 stable flies per hectare. However, up to 1 million house flies, 0.45 million lesser house flies, Fannia cannicularis L., and 11,000 stable flies per hectare may be produced from surface dressings of poultry litter associated with turf production. Other nuisance flies present in poultry litter included the false stable fly, Muscina stabulans (Fallén), bluebodied blowfly, Calliphora dubia Hardy, black carrion fly, Hydrotaea rostrata Robineau-Desvoidy, Australian sheep blowfly, Lucilia cuprina Wiedemann, and flesh flies (Sarcophagidae). Only house flies developed in poultry litter for the first 4 d after application in the field. Stable flies were not present in poultry litter until 4-7 d after application, and were the only fly species developing in litter > 9 d after application.

The bacterial flagellar switch complex is getting more complex

PubMed Central

Cohen-Ben-Lulu, Galit N; Francis, Noreen R; Shimoni, Eyal; Noy, Dror; Davidov, Yaacov; Prasad, Krishna; Sagi, Yael; Cecchini, Gary; Johnstone, Rose M; Eisenbach, Michael

2008-01-01

The mechanism of function of the bacterial flagellar switch, which determines the direction of flagellar rotation and is essential for chemotaxis, has remained an enigma for many years. Here we show that the switch complex associates with the membrane-bound respiratory protein fumarate reductase (FRD). We provide evidence that FRD binds to preparations of isolated switch complexes, forms a 1:1 complex with the switch protein FliG, and that this interaction is required for both flagellar assembly and switching the direction of flagellar rotation. We further show that fumarate, known to be a clockwise/switch factor, affects the direction of flagellar rotation through FRD. These results not only uncover a new component important for switching and flagellar assembly, but they also reveal that FRD, an enzyme known to be primarily expressed and functional under anaerobic conditions in Escherichia coli, nonetheless, has important, unexpected functions under aerobic conditions. PMID:18337747

Influence of fly-ash produced by lignite power station on humic substances in ectohumus horizons of Podzols

NASA Astrophysics Data System (ADS)

Weber, Jerzy; Jerzykiewicz, Maria; Jamroz, Elżbieta; Kocowicz, Andrzej; Dębicka, Magdalena; Ćwieląg-Piasecka, Irmina

2017-04-01

Literature on fly-ash influence on the environment report mainly on alkalization effect on vegetation and changes in chemistry of forest floor. As far as now soils were examined only for changes in pH in surface horizons, physical properties and heavy metal solubility. Soil properties strongly depend on soil organic matter content and humic substances properties, thus their modification plays a crucial role in soil forming processes and changes in the environment. From the other side, the alkalization effects on podzolization processes and particularly on humic substances have not been recognized. The aim of this paper was to characterize changes in properties of humic substances in ectohumus horizons of Podzols affected by alkali blown out from fly-ash dumping site of power station Bełchatów, central Poland. The objects of the investigation were Podzols derived from loose quartz sand, developed under pine forest. They surround the dumping site, which was established to store wastes from lignite combustion in Bełchatów power station. The samples were collected from ectohumus horizons in direct vicinity of the dumping site (50 m) as well as in the control area (7.3 km away) in five replications. Determination of elemental composition and spectroscopic analysis (EPR, FT-IR, ICP-OES and UV-Vis) were performed for humic acids, fulvic acids and humines extracted with standard IHSS procedure. An increase of pH in ectohumus horizons caused by the influence of fly-ash leads to change in humic substances structure. Obtained results showed that humic and fulvic acids from fly-ash affected Podzols indicated higher contents of nitrogen and sulphur, as well as higher O/C and lower C/N ratios. This points out a higher degree of their humification. Also EPR analyses of humic acids and humins affected by fly-ash indicated higher metal ions concentrations. However, the increase of Mn and Fe ions concentration did not affect the Fe(III) and Mn(II) band intensities of EPR spectra. This may suggest the presence of other forms (other oxidation state) of Mn and Fe ions, that are diamagnetic and hence EPR silent. Lower g-factors values of radicals built-in humic substances extracted from fly-ash affected soils are associated with more condensed structures with lower content of oxygen functional groups. Decrease of free radicals concentration in Podzols affected by fly-ash is correlated with an increase of the transition metal ions, such as Mn(II) and Fe(III), which interact (antiferromagnetically) with semiquinone radicals built-in humic substances macromolecules. Humic acids from fly-ash affected site indicated lower values of E4/E6 ratio, which confirmed higher molecular weight of the molecules. Thus the humic fractions from ectohumus horizon of the fly-ash affected area could be described as having heavier, more complex structure then those from control area. Above mentioned modification of humic substances may contribute to restriction of the podzolization processes, and transformation of underlying eluvial horizons into transitional AE horizons. Furthermore, due to transformation and translocation of organic components, illuvial Bhs horizons can be transformed into Bs horizons.

KSC-02pp1755

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. - Chickasaw Indian princesses "sign" the Lord's Prayer during a Native American Ceremony at the Rocket Garden in the KSC Visitor Complex. The princesses are Crystal Underwood, Julie Underwood and Tamela Alexander. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

KSC-02pp1754

NASA Image and Video Library

2002-11-10

KENNEDY SPACE CENTER, FLA. - Chickasaw Indian princesses "sign" the Lord's Prayer during a Native American Ceremony at the Rocket Garden in the KSC Visitor Complex. The princesses are Crystal Underwood, Julie Underwood and Tamela Alexander. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

In-situ ATR-FTIR and surface complexation modeling studies on the adsorption of dimethylarsenic acid and p-arsanilic acid on iron-(oxyhydr)oxides

USDA-ARS?s Scientific Manuscript database

Arsenic is an element that exists naturally in many rocks and minerals around the world. It also accumulates in petroleum, shale, oil sands and coal deposits as a result of biogeochemical processes, and it has been found in fly ash from the combustion of solid biofuels. Arsenic compounds in their o...

Activities commemorating John B. Herrington as first Native American astronaut

NASA Technical Reports Server (NTRS)

2002-01-01

KENNEDY SPACE CENTER, FLA. -- Chickasaw Indian princesses seen here contributed to a pre-launch Native American ceremony at the Rocket Garden in the KSC Visitor Complex by leading a prayer. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

Streamlining DOD Acquisitions: Balancing Schedule with Complexity

DTIC Science & Technology

2006-09-01

from them has a distinct industrial flavor: streamlined processes, benchmarking, and business models . The requirements generation com- munity led by... model ), and the Department of the Navy assumed program lead. [Stable Program Inputs (-)] By 1984, the program goals included delivery of 913 V-22...they subsequently specified a crew of two. [Stable Program Input (-)] The contractor team won in a “fly-off” solely via modeling and simulation

An integrative approach to unravel the Ceratitis FAR (Diptera, Tephritidae) cryptic species complex: a review

PubMed Central

De Meyer, Marc; Delatte, Hélène; Ekesi, Sunday; Jordaens, Kurt; Kalinová, Blanka; Manrakhan, Aruna; Mwatawala, Maulid; Steck, Gary; Van Cann, Joannes; Vaníčková, Lucie; Břízová, Radka; Virgilio, Massimiliano

2015-01-01

Abstract This paper reviews all information gathered from different disciplines and studies to resolve the species status within the Ceratitis FAR (Ceratitis fasciventris, Ceratitis anonae, Ceratitis rosa) complex, a group of polyphagous fruit fly pest species (Diptera, Tephritidae) from Africa. It includes information on larval and adult morphology, wing morphometrics, cuticular hydrocarbons, pheromones, microsatellites, developmental physiology and geographic distribution. The general consensus is that the FAR complex comprises Ceratitis anonae, two species within Ceratitis rosa (so-called R1 and R2) and two putatitve species under Ceratitis fasciventris. The information regarding the latter is, however, too limited to draw final conclusions on specific status. Evidence for this recognition is discussed with reference to publications providing further details. PMID:26798270

2017 ASCAN Tour of KSC

NASA Image and Video Library

2018-05-01

The 2017 class of astronaut candidates tour Boeing's Commercial Crew and Cargo Facility at NASA's Kennedy Space Center in Florida on May 1. They are at the center for a familiarization tour of facilities, including the Neil Armstrong Operations and Checkout Building high bay; the Launch Control Center, Launch Complex 39B, and the Vehicle Assembly Building. They also toured United Launch Alliance's Space Launch Complex 41 at Cape Canaveral Air Force Station, and SpaceX's Launch Complex 39A at Kennedy. The candidates will spend about two years getting to know the space station systems and learning how to spacewalk, speak Russian, control the International Space Station's robotic arm and fly T-38s, before they're eligible to be assigned to a mission.

2017 ASCAN Tour of KSC

NASA Image and Video Library

2018-05-01

The 2017 class of astronaut candidates arrive at Boeing's Commercial Crew and Cargo Facility at NASA's Kennedy Space Center in Florida on May 1. They are at the center for a familiarization tour of facilities, including the Neil Armstrong Operations and Checkout Building high bay; the Launch Control Center, Launch Complex 39B, and the Vehicle Assembly Building. They also toured United Launch Alliance's Space Launch Complex 41 at Cape Canaveral Air Force Station, and SpaceX's Launch Complex 39A at Kennedy. The candidates will spend about two years getting to know the space station systems and learning how to spacewalk, speak Russian, control the International Space Station's robotic arm and fly T-38s, before they're eligible to be assigned to a mission.

Interactions of carbon dioxide and food odours in Drosophila: olfactory hedonics and sensory neuron properties.

PubMed

Faucher, Cécile P; Hilker, Monika; de Bruyne, Marien

2013-01-01

Behavioural responses of animals to volatiles in their environment are generally dependent on context. Most natural odours are mixtures of components that can each induce different behaviours when presented on their own. We have investigated how a complex of two olfactory stimuli is evaluated by Drosophila flies in a free-flying two-trap choice assay and how these stimuli are encoded in olfactory receptor neurons. We first observed that volatiles from apple cider vinegar attracted flies while carbon dioxide (CO2) was avoided, confirming their inherent positive and negative values. In contradiction with previous results obtained from walking flies in a four-field olfactometer, in the present assay the addition of CO2 to vinegar increased rather than decreased the attractiveness of vinegar. This effect was female-specific even though males and females responded similarly to CO2 and vinegar on their own. To test whether the female-specific behavioural response to the mixture correlated with a sexual dimorphism at the peripheral level we recorded from olfactory receptor neurons stimulated with vinegar, CO2 and their combination. Responses to vinegar were obtained from three neuron classes, two of them housed with the CO2-responsive neuron in ab1 sensilla. Sensitivity of these neurons to both CO2 and vinegar per se did not differ between males and females and responses from female neurons did not change when CO2 and vinegar were presented simultaneously. We also found that CO2-sensitive neurons are particularly well adapted to respond rapidly to small concentration changes irrespective of background CO2 levels. The ability to encode temporal properties of stimulations differs considerably between CO2- and vinegar-sensitive neurons. These properties may have important implications for in-flight navigation when rapid responses to fragmented odour plumes are crucial to locate odour sources. However, the flies' sex-specific response to the CO2-vinegar combination and the context-dependent hedonics most likely originate from central rather than peripheral processing.

Evolutionary implications of mitochondrial genetic variation: mitochondrial genetic effects on OXPHOS respiration and mitochondrial quantity change with age and sex in fruit flies.

PubMed

Wolff, J N; Pichaud, N; Camus, M F; Côté, G; Blier, P U; Dowling, D K

2016-04-01

The ancient acquisition of the mitochondrion into the ancestor of modern-day eukaryotes is thought to have been pivotal in facilitating the evolution of complex life. Mitochondria retain their own diminutive genome, with mitochondrial genes encoding core subunits involved in oxidative phosphorylation. Traditionally, it was assumed that there was little scope for genetic variation to accumulate and be maintained within the mitochondrial genome. However, in the past decade, mitochondrial genetic variation has been routinely tied to the expression of life-history traits such as fertility, development and longevity. To examine whether these broad-scale effects on life-history trait expression might ultimately find their root in mitochondrially mediated effects on core bioenergetic function, we measured the effects of genetic variation across twelve different mitochondrial haplotypes on respiratory capacity and mitochondrial quantity in the fruit fly, Drosophila melanogaster. We used strains of flies that differed only in their mitochondrial haplotype, and tested each sex separately at two different adult ages. Mitochondrial haplotypes affected both respiratory capacity and mitochondrial quantity. However, these effects were highly context-dependent, with the genetic effects contingent on both the sex and the age of the flies. These sex- and age-specific genetic effects are likely to resonate across the entire organismal life-history, providing insights into how mitochondrial genetic variation may contribute to sex-specific trajectories of life-history evolution. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

Flight initiation and maintenance deficits in flies with genetically altered biogenic amine levels.

PubMed

Brembs, Björn; Christiansen, Frauke; Pflüger, Hans Joachim; Duch, Carsten

2007-10-10

Insect flight is one of the fastest, most intense and most energy-demanding motor behaviors. It is modulated on multiple levels by the biogenic amine octopamine. Within the CNS, octopamine acts directly on the flight central pattern generator, and it affects motivational states. In the periphery, octopamine sensitizes sensory receptors, alters muscle contraction kinetics, and enhances flight muscle glycolysis. This study addresses the roles for octopamine and its precursor tyramine in flight behavior by genetic and pharmacological manipulation in Drosophila. Octopamine is not the natural signal for flight initiation because flies lacking octopamine [tyramine-beta-hydroxylase (TbetaH) null mutants] can fly. However, they show profound differences with respect to flight initiation and flight maintenance compared with wild-type controls. The morphology, kinematics, and development of the flight machinery are not impaired in TbetaH mutants because wing-beat frequencies and amplitudes, flight muscle structure, and overall dendritic structure of flight motoneurons are unaffected in TbetaH mutants. Accordingly, the flight behavior phenotypes can be rescued acutely in adult flies. Flight deficits are rescued by substituting octopamine but also by blocking the receptors for tyramine, which is enriched in TbetaH mutants. Conversely, ablating all neurons containing octopamine or tyramine phenocopies TbetaH mutants. Therefore, both octopamine and tyramine systems are simultaneously involved in regulating flight initiation and maintenance. Different sets of rescue experiments indicate different sites of action for both amines. These findings are consistent with a complex system of multiple amines orchestrating the control of motor behaviors on multiple levels rather than single amines eliciting single behaviors.

Degradation of TBC Systems in Environments Relevant to Advanced Gas Turbines for IGCC Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gleeson, Brian

2014-09-30

Air plasma sprayed (APS) thermal barrier coatings (TBCs) are used to provide thermal insulation for the hottest components in gas turbines. Zirconia stabilized with 7wt% yttria (7YSZ) is the most common ceramic top coat used for turbine blades. The 7YSZ coating can be degraded from the buildup of fly-ash deposits created in the power-generation process. Fly ash from an integrated gasification combined cycle (IGCC) system can result from coal-based syngas. TBCs are also exposed to harsh gas environments containing CO 2, SO 2, and steam. Degradation from the combined effects of fly ash and harsh gas atmospheres has the potentialmore » to severely limit TBC lifetimes. The main objective of this study was to use lab-scale testing to systematically elucidate the interplay between prototypical deposit chemistries (i.e., ash and its constituents, K 2SO 4, and FeS) and environmental oxidants (i.e., O 2, H 2O and CO 2) on the degradation behavior of advanced TBC systems. Several mechanisms of early TBC failure were identified, as were the specific fly-ash constituents responsible for degradation. The reactivity of MCrAlY bondcoats used in TBC systems was also investigated. The specific roles of oxide and sulfate components were assessed, together with the complex interplay between gas composition, deposit chemistry and alloy reactivity. Bondcoat composition design strategies to mitigate corrosion were established, particularly with regard to controlling phase constitution and the amount of reactive elements the bondcoat contains in order to achieve optimal corrosion resistance.« less

Genetic Structure of Lutzomyia longipalpis Populations in Mato Grosso Do Sul, Brazil, Based on Microsatellite Markers

PubMed Central

Santos, Mirella F. C.; Ribolla, Paulo E. M.; Alonso, Diego P.; Andrade-Filho, José D.; Casaril, Aline E.; Ferreira, Alda M. T.; Fernandes, Carlos E. S.; Brazil, Reginaldo P.; Oliveira, Alessandra G.

2013-01-01

Background Lutzomyia longipalpis (Diptera: Psychodidae) is the major vector of Leishmania (Leishmania) infantum and thus plays a crucial role in the epidemiology of American visceral leishmaniasis (AVL). This vector is the best studied species of sand fly in the Neotropical region. Many studies claim that this vector is in fact a species complex; however there is still no consensus regarding the number of species that belong into this complex or the geographical distribution of sibling species. The aim of the present study was to analyze the genetic relationships within Lu. longipalpis populations in the state of Mato Grosso do Sul (MS), Brazil. Methodology/Principal Findings We collected 30 Lu. longipalpis (15 females and 15 males) from five localities (Campo Grande, Três Lagoas, Aquidauana, Miranda and Bonito) and 30 Lu. Cruzi from Corumbá, totaling 180 sandflies from MS, and 30 Lu. longipalpis from Estrela de Alagoas, state of Alagoas (AL), Northeast Brazil. We show that eight previously described microsatellite loci were sufficient in distinguishing Lu. longipalpis from Lu. Cruzi, which is a closely related species, and in differentiating between Lu. longipalpis collected in MS versus Estrela de Alagoas. Analyses of the genotypes revealed introgression between sympatric Lu. longipalpis and Lu. Cruzi. Conclusions/Significance Our findings support the hypothesis of cryptic species within the Lu. longipalpis complex. Furthermore, our data revealed introgression between Lu. longipalpis and Lu. cruzi. This phenomenon should be further investigated to determine the level and incidence of hybridization between these two species. We also demonstrated that microsatellite markers are a powerful tool for differentiating sand fly populations and species. The present study has elucidated the population structure of Lu. longipalpis in MS and, by extension, the Neotropical Lu. longipalpis complex itself. PMID:24066129

Eye evolution at high resolution: the neuron as a unit of homology.

PubMed

Erclik, Ted; Hartenstein, Volker; McInnes, Roderick R; Lipshitz, Howard D

2009-08-01

Based on differences in morphology, photoreceptor-type usage and lens composition it has been proposed that complex eyes have evolved independently many times. The remarkable observation that different eye types rely on a conserved network of genes (including Pax6/eyeless) for their formation has led to the revised proposal that disparate complex eye types have evolved from a shared and simpler prototype. Did this ancestral eye already contain the neural circuitry required for image processing? And what were the evolutionary events that led to the formation of complex visual systems, such as those found in vertebrates and insects? The recent identification of unexpected cell-type homologies between neurons in the vertebrate and Drosophila visual systems has led to two proposed models for the evolution of complex visual systems from a simple prototype. The first, as an extension of the finding that the neurons of the vertebrate retina share homologies with both insect (rhabdomeric) and vertebrate (ciliary) photoreceptor cell types, suggests that the vertebrate retina is a composite structure, made up of neurons that have evolved from two spatially separate ancestral photoreceptor populations. The second model, based largely on the conserved role for the Vsx homeobox genes in photoreceptor-target neuron development, suggests that the last common ancestor of vertebrates and flies already possessed a relatively sophisticated visual system that contained a mixture of rhabdomeric and ciliary photoreceptors as well as their first- and second-order target neurons. The vertebrate retina and fly visual system would have subsequently evolved by elaborating on this ancestral neural circuit. Here we present evidence for these two cell-type homology-based models and discuss their implications.

The Building Blocks of Life Move from Ground to Tree to Animal and Back to Ground

NASA Astrophysics Data System (ADS)

Davidson, E. A.

2015-12-01

I generally use combinations of big words to describe my science, such as biogeochemistry, ecosystem ecology, nutrient cycling, stoichiometry, tropical deforestation, land-use change, agricultural intensification, eutrophication, greenhouse gas emissions, and sustainable development. I didn't expect to use any of these words, but I was surprised that I couldn't use some others that seem simple enough to me, such as farm, plant, soil, and forest. I landed on "building blocks" as my metaphor for the forms of carbon, nitrogen, phosphorus, and other elements that I study as they cycle through and among ecosystems. I study what makes trees and other kinds of life grow. We all know that they need the sun and that they take up water from the ground, but what else do trees need from the ground? What do animals that eat leaves and wood get from the trees? Just as we need building blocks to grow our bodies, trees and animals also need building blocks for growing their bodies. Trees get part of their building blocks from the ground and animals get theirs from what they eat. When animals poop and when leaves fall, some of their building blocks return to the ground. When they die, their building blocks also go back to the ground. I also study what happens to the ground, the water, and the air when we cut down trees, kill or shoo away the animals, and make fields to grow our food. Can we grow enough food and still keep the ground, water, and air clean? I think the answer is yes, but it will take better understanding of how all of those building blocks fit together and move around, from ground to tree to animal and back to ground.

Treatment of fly ash for use in concrete

DOEpatents

Boxley, Chett [Park City, UT; Akash, Akash [Salt lake City, UT; Zhao, Qiang [Natick, MA

2012-05-08

A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

Treatment of fly ash for use in concrete

DOEpatents

Boxley, Chett; Akash, Akash; Zhao, Qiang

2013-01-08

A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

Adaptation without parameter change: Dynamic gain control in motion detection

PubMed Central

Borst, Alexander; Flanagin, Virginia L.; Sompolinsky, Haim

2005-01-01

Many sensory systems adapt their input-output relationship to changes in the statistics of the ambient stimulus. Such adaptive behavior has been measured in a motion detection sensitive neuron of the fly visual system, H1. The rapid adaptation of the velocity response gain has been interpreted as evidence of optimal matching of the H1 response to the dynamic range of the stimulus, thereby maximizing its information transmission. Here, we show that correlation-type motion detectors, which are commonly thought to underlie fly motion vision, intrinsically possess adaptive properties. Increasing the amplitude of the velocity fluctuations leads to a decrease of the effective gain and the time constant of the velocity response without any change in the parameters of these detectors. The seemingly complex property of this adaptation turns out to be a straightforward consequence of the multidimensionality of the stimulus and the nonlinear nature of the system. PMID:15833815

Different parameters support generalization and discrimination learning in Drosophila at the flight simulator.

PubMed

Brembs, Björn; Hempel de Ibarra, Natalie

2006-01-01

We have used a genetically tractable model system, the fruit fly Drosophila melanogaster to study the interdependence between sensory processing and associative processing on learning performance. We investigated the influence of variations in the physical and predictive properties of color stimuli in several different operant-conditioning procedures on the subsequent learning performance. These procedures included context and stimulus generalization as well as color, compound, and conditional discrimination (colors and patterns). A surprisingly complex dependence of the learning performance on the colors' physical and predictive properties emerged, which was clarified by taking into account the fly-subjective perception of the color stimuli. Based on estimates of the stimuli's color and brightness values, we propose that the different tasks are supported by different parameters of the color stimuli; generalization occurs only if the chromaticity is sufficiently similar, whereas discrimination learning relies on brightness differences.

Flies and humans share a motion estimation strategy that exploits natural scene statistics

PubMed Central

Clark, Damon A.; Fitzgerald, James E.; Ales, Justin M.; Gohl, Daryl M.; Silies, Marion A.; Norcia, Anthony M.; Clandinin, Thomas R.

2014-01-01

Sighted animals extract motion information from visual scenes by processing spatiotemporal patterns of light falling on the retina. The dominant models for motion estimation exploit intensity correlations only between pairs of points in space and time. Moving natural scenes, however, contain more complex correlations. Here we show that fly and human visual systems encode the combined direction and contrast polarity of moving edges using triple correlations that enhance motion estimation in natural environments. Both species extract triple correlations with neural substrates tuned for light or dark edges, and sensitivity to specific triple correlations is retained even as light and dark edge motion signals are combined. Thus, both species separately process light and dark image contrasts to capture motion signatures that can improve estimation accuracy. This striking convergence argues that statistical structures in natural scenes have profoundly affected visual processing, driving a common computational strategy over 500 million years of evolution. PMID:24390225

Threat expert system technology advisor

NASA Technical Reports Server (NTRS)

Kurrasch, E. R.; Tripp, L. R.

1987-01-01

A prototype expert system was developed to determine the feasibility of using expert system technology to enhance the performance and survivability of helicopter pilots in a combat threat environment while flying NOE (Nap of the Earth) missions. The basis for the concept is the potential of using an Expert System Advisor to reduce the extreme overloading of the pilot who flies NOE mission below treetop level at approximately 40 knots while performing several other functions. The ultimate goal is to develop a Threat Expert System Advisor which provides threat information and advice that are better than even a highly experienced copilot. The results clearly show that the NOE pilot needs all the help in decision aiding and threat situation awareness that he can get. It clearly shows that heuristics are important and that an expert system for combat NOE helicopter missions can be of great help to the pilot in complex threat situations and in making decisions.

Using Natural Language to Enable Mission Managers to Control Multiple Heterogeneous UAVs

NASA Technical Reports Server (NTRS)

Trujillo, Anna C.; Puig-Navarro, Javier; Mehdi, S. Bilal; Mcquarry, A. Kyle

2016-01-01

The availability of highly capable, yet relatively cheap, unmanned aerial vehicles (UAVs) is opening up new areas of use for hobbyists and for commercial activities. This research is developing methods beyond classical control-stick pilot inputs, to allow operators to manage complex missions without in-depth vehicle expertise. These missions may entail several heterogeneous UAVs flying coordinated patterns or flying multiple trajectories deconflicted in time or space to predefined locations. This paper describes the functionality and preliminary usability measures of an interface that allows an operator to define a mission using speech inputs. With a defined and simple vocabulary, operators can input the vast majority of mission parameters using simple, intuitive voice commands. Although the operator interface is simple, it is based upon autonomous algorithms that allow the mission to proceed with minimal input from the operator. This paper also describes these underlying algorithms that allow an operator to manage several UAVs.

3D Holographic Observatory for Long-term Monitoring of Complex Behaviors in Drosophila

NASA Astrophysics Data System (ADS)

Kumar, S. Santosh; Sun, Yaning; Zou, Sige; Hong, Jiarong

2016-09-01

Drosophila is an excellent model organism towards understanding the cognitive function, aging and neurodegeneration in humans. The effects of aging and other long-term dynamics on the behavior serve as important biomarkers in identifying such changes to the brain. In this regard, we are presenting a new imaging technique for lifetime monitoring of Drosophila in 3D at spatial and temporal resolutions capable of resolving the motion of limbs and wings using holographic principles. The developed system is capable of monitoring and extracting various behavioral parameters, such as ethograms and spatial distributions, from a group of flies simultaneously. This technique can image complicated leg and wing motions of flies at a resolution, which allows capturing specific landing responses from the same data set. Overall, this system provides a unique opportunity for high throughput screenings of behavioral changes in 3D over a long term in Drosophila.

Induction of autophagy by spermidine promotes longevity.

PubMed

Eisenberg, Tobias; Knauer, Heide; Schauer, Alexandra; Büttner, Sabrina; Ruckenstuhl, Christoph; Carmona-Gutierrez, Didac; Ring, Julia; Schroeder, Sabrina; Magnes, Christoph; Antonacci, Lucia; Fussi, Heike; Deszcz, Luiza; Hartl, Regina; Schraml, Elisabeth; Criollo, Alfredo; Megalou, Evgenia; Weiskopf, Daniela; Laun, Peter; Heeren, Gino; Breitenbach, Michael; Grubeck-Loebenstein, Beatrix; Herker, Eva; Fahrenkrog, Birthe; Fröhlich, Kai-Uwe; Sinner, Frank; Tavernarakis, Nektarios; Minois, Nadege; Kroemer, Guido; Madeo, Frank

2009-11-01

Ageing results from complex genetically and epigenetically programmed processes that are elicited in part by noxious or stressful events that cause programmed cell death. Here, we report that administration of spermidine, a natural polyamine whose intracellular concentration declines during human ageing, markedly extended the lifespan of yeast, flies and worms, and human immune cells. In addition, spermidine administration potently inhibited oxidative stress in ageing mice. In ageing yeast, spermidine treatment triggered epigenetic deacetylation of histone H3 through inhibition of histone acetyltransferases (HAT), suppressing oxidative stress and necrosis. Conversely, depletion of endogenous polyamines led to hyperacetylation, generation of reactive oxygen species, early necrotic death and decreased lifespan. The altered acetylation status of the chromatin led to significant upregulation of various autophagy-related transcripts, triggering autophagy in yeast, flies, worms and human cells. Finally, we found that enhanced autophagy is crucial for polyamine-induced suppression of necrosis and enhanced longevity.

Time-lapse cinematography in living Drosophila tissues: preparation of material.

PubMed

Davis, Ilan; Parton, Richard M

2006-11-01

The fruit fly, Drosophila melanogaster, has been an extraordinarily successful model organism for studying the genetic basis of development and evolution. It is arguably the best-understood complex multicellular model system, owing its success to many factors. Recent developments in imaging techniques, in particular sophisticated fluorescence microscopy methods and equipment, now allow cellular events to be studied at high resolution in living material. This ability has enabled the study of features that tend to be lost or damaged by fixation, such as transient or dynamic events. Although many of the techniques of live cell imaging in Drosophila are shared with the greater community of cell biologists working on other model systems, studying living fly tissues presents unique difficulties in keeping the cells alive, introducing fluorescent probes, and imaging through thick hazy cytoplasm. This protocol outlines the preparation of major tissue types amenable to study by time-lapse cinematography and different methods for keeping them alive.

The Drosophila Clock Neuron Network Features Diverse Coupling Modes and Requires Network-wide Coherence for Robust Circadian Rhythms.

PubMed

Yao, Zepeng; Bennett, Amelia J; Clem, Jenna L; Shafer, Orie T

2016-12-13

In animals, networks of clock neurons containing molecular clocks orchestrate daily rhythms in physiology and behavior. However, how various types of clock neurons communicate and coordinate with one another to produce coherent circadian rhythms is not well understood. Here, we investigate clock neuron coupling in the brain of Drosophila and demonstrate that the fly's various groups of clock neurons display unique and complex coupling relationships to core pacemaker neurons. Furthermore, we find that coordinated free-running rhythms require molecular clock synchrony not only within the well-characterized lateral clock neuron classes but also between lateral clock neurons and dorsal clock neurons. These results uncover unexpected patterns of coupling in the clock neuron network and reveal that robust free-running behavioral rhythms require a coherence of molecular oscillations across most of the fly's clock neuron network. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

KSC-2011-6870

NASA Image and Video Library

2011-09-10

CAPE CANAVERAL, Fla. – A U.S. Air Force helicopter flies overhead as the United Launch Alliance Delta II Heavy rocket sits on Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida waiting to launch NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission to the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Kim Shiflett

The Drosophila Circadian Pacemaker Circuit: Pas de Deux or Tarantella?

PubMed Central

Sheeba, Vasu; Kaneko, Maki; Sharma, Vijay Kumar; Holmes, Todd C.

2008-01-01

Molecular genetic analysis of the fruit fly Drosophila melanogaster has revolutionized our understanding of the transcription/translation loop mechanisms underlying the circadian molecular oscillator. More recently, Drosophila has been used to understand how different neuronal groups within the circadian pacemaker circuit interact to regulate the overall behavior of the fly in response to daily cyclic environmental cues as well as seasonal changes. Our present understanding of circadian timekeeping at the molecular and circuit level is discussed with a critical evaluation of the strengths and weaknesses of present models. Two models for circadian neural circuits are compared: one that posits that two anatomically distinct oscillators control the synchronization to the two major daily morning and evening transitions, versus a distributed network model that posits that many cell-autonomous oscillators are coordinated in a complex fashion and respond via plastic mechanisms to changes in environmental cues. PMID:18307108

Tephritid Integrative Taxonomy: Where We Are Now, with a Focus on the Resolution of Three Tropical Fruit Fly Species Complexes.

PubMed

Schutze, Mark K; Virgilio, Massimiliano; Norrbom, Allen; Clarke, Anthony R

2017-01-31

Accurate species delimitation underpins good taxonomy. Formalization of integrative taxonomy in the past decade has provided a framework for using multidisciplinary data to make species delimitation hypotheses more rigorous. We address the current state of integrative taxonomy by using as a case study an international project targeted at resolving three important tephritid species complexes: Bactrocera dorsalis complex, Anastrepha fraterculus complex, and Ceratitis FAR (C. fasciventris, C. anonae, C. rosa) complex. The integrative taxonomic approach has helped deliver significant advances in resolving these complexes: It has been used to identify some taxa as belonging to the same biological species as well as to confirm hidden cryptic diversity under a single taxonomic name. Nevertheless, the general application of integrative taxonomy has not been without issue, revealing challenges that must be considered when undertaking an integrative taxonomy project. Scrutiny of this international case study provides a unique opportunity to document lessons learned for the benefit of not only tephritid taxonomists, but also the wider taxonomic community.

MOF-associated complexes ensure stem cell identity and Xist repression

PubMed Central

Chelmicki, Tomasz; Dündar, Friederike; Ramírez, Fidel; Gendrel, Anne-Valerie; Wright, Patrick Rudolf; Videm, Pavankumar; Backofen, Rolf; Heard, Edith; Manke, Thomas; Akhtar, Asifa

2014-01-01

Histone acetyl transferases (HATs) play distinct roles in many cellular processes and are frequently misregulated in cancers. Here, we study the regulatory potential of MYST1-(MOF)-containing MSL and NSL complexes in mouse embryonic stem cells (ESCs) and neuronal progenitors. We find that both complexes influence transcription by targeting promoters and TSS-distal enhancers. In contrast to flies, the MSL complex is not exclusively enriched on the X chromosome, yet it is crucial for mammalian X chromosome regulation as it specifically regulates Tsix, the major repressor of Xist lncRNA. MSL depletion leads to decreased Tsix expression, reduced REX1 recruitment, and consequently, enhanced accumulation of Xist and variable numbers of inactivated X chromosomes during early differentiation. The NSL complex provides additional, Tsix-independent repression of Xist by maintaining pluripotency. MSL and NSL complexes therefore act synergistically by using distinct pathways to ensure a fail-safe mechanism for the repression of X inactivation in ESCs. DOI: http://dx.doi.org/10.7554/eLife.02024.001 PMID:24842875

Solar-powered electrocuting trap for controlling house flies and stable flies (Diptera: Muscidae).

PubMed

Pickens, L G; Mills, G D

1993-09-01

A portable trap was constructed that was visually attractive to house flies, Musca domestica L., and stable flies, Stomoxys calcitrans (L.), outdoors. The trap was made of a white and yellow pyramid placed on top of a white vertical base that had large cutouts in each side. Attracted flies were killed by means of solar-powered electrocuting grids. Three traps killed an average of 1,360 house flies and 1,190 stable flies per day at a manure dump and were effective in attracting flies under both cool (< 23 degrees C) and warm (> 30 degrees C) temperatures. Both species of flies were most attracted to the eastern side of the trap, but house flies preferred yellow in cool mornings and white in warm afternoons. When air temperatures were > 30 degrees C, both house flies and stable flies went into the shaded base of the trap or into tunnels. Most house flies were killed on the pyramidal top of the trap, whereas most stable flies were killed on the vertical base. Opaque fiberglass tunnels with central electrocuting grids were simpler and cheaper, although less effective, for stable flies.

Pollen recovered from the exoskeleton of stable flies, Stomoxys calcitrans (L.) in Gainesville, Florida

USDA-ARS?s Scientific Manuscript database

Stable flies are pestiferous blood feeding flies that attack animals and humans. Besides consuming blood, these flies will also visit flowers to take nectar meals. When feeding on nectar, flies become coated with pollen which can be used to identify flowers used by the flies. Recently, flies cove...

Bartonella spp. DNA Associated with Biting Flies from California

PubMed Central

Chung, Crystal Y.; Kasten, Rickie W.; Paff, Sandra M.; Van Horn, Brian A.; Vayssier-Taussat, Muriel; Boulouis, Henri-Jean

2004-01-01

Bartonella DNA was investigated in 104 horn flies (Haematobia spp.), 60 stable flies (Stomoxys spp.), 11 deer flies (Chrysops spp.), and 11 horse flies (Tabanus spp.) collected on cattle in California. Partial sequencing indicated B. bovis DNA in the horn fly pool and B. henselae type M DNA in one stable fly. PMID:15324557

Biomechanics and biomimetics in insect-inspired flight systems

PubMed Central

Liu, Hao; Ravi, Sridhar; Kolomenskiy, Dmitry; Tanaka, Hiroto

2016-01-01

Insect- and bird-size drones—micro air vehicles (MAV) that can perform autonomous flight in natural and man-made environments are now an active and well-integrated research area. MAVs normally operate at a low speed in a Reynolds number regime of 104–105 or lower, in which most flying animals of insects, birds and bats fly, and encounter unconventional challenges in generating sufficient aerodynamic forces to stay airborne and in controlling flight autonomy to achieve complex manoeuvres. Flying insects that power and control flight by flapping wings are capable of sophisticated aerodynamic force production and precise, agile manoeuvring, through an integrated system consisting of wings to generate aerodynamic force, muscles to move the wings and a control system to modulate power output from the muscles. In this article, we give a selective review on the state of the art of biomechanics in bioinspired flight systems in terms of flapping and flexible wing aerodynamics, flight dynamics and stability, passive and active mechanisms in stabilization and control, as well as flapping flight in unsteady environments. We further highlight recent advances in biomimetics of flapping-wing MAVs with a specific focus on insect-inspired wing design and fabrication, as well as sensing systems. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’. PMID:27528780

Social context influences chemical communication in D. melanogaster males.

PubMed

Kent, Clement; Azanchi, Reza; Smith, Ben; Formosa, Amanda; Levine, Joel D

2008-09-23

Chemical communication mediates social interactions in insects. For the fruit fly, D. melanogaster, the chemical display is a key fitness trait because it leads to mating. An exchange of cues that resembles a dialogue between males and females is enacted by pheromones, chemical signals that pass between individual flies to alter physiology and behavior. Chemical signals also affect the timing of locomotor activity and sleep. We investigated genetic and environmental determinants of chemical communication. To evaluate the role of the social environment, we extracted a chemical blend from individual males selected from groups composed of one genotype and compared these extracts to those from groups of mixed genotypes. To evaluate the role of the physical environment, these comparisons were performed under a light-dark cycle or in constant darkness. Here, we show that chemical signaling is affected by the social environment, light-dark cycle, and genotype as well as the complex interplay of these variables. Gene-by-environment interactions produce highly significant effects on chemical signaling. We also examined individual responses within the groups. Strikingly, the response of one wild-type fly to another is modulated by the genotypic composition of his neighbors. Chemical signaling in D. melanogaster may be a "fickle" trait that depends on the individual's social background.

ASSESSING THE POTENTIAL EFFECTS OF FUNGICIDES ON NONTARGET GUT FUNGI (TRICHOMYCETES) AND THEIR ASSOCIATED LARVAL BLACK FLY HOSTS

PubMed Central

Wilson, Emma R.; Smalling, Kelly L.; Reilly, Timothy J.; Gray, Elmer; Bond, Laura; Steele, Lance; Kandel, Prasanna; Chamberlin, Alison; Gause, Justin; Reynolds, Nicole; Robertson, Ian; Novak, Stephen; Feris, Kevin; White, Merlin M.

2015-01-01

Fungicides are moderately hydrophobic and have been detected in water and sediment, particularly in agricultural watersheds, but typically are not included in routine water quality monitoring efforts. This is despite their widespread use and frequent application to combat fungal pathogens. Whereas the efficacy of these compounds on fungal pathogens is well documented, little is known about their effects on nontarget fungi. This pilot study, a field survey in southwestern Idaho from April to December 2010 on four streams with varying pesticide inputs (two agricultural and two reference sites), was conducted to assess nontarget impact of fungicides on gut fungi, or trichomycetes. Tissues of larval black flies (Diptera: Simuliidae), hosts of gut fungi, were analyzed for pesticide accumulation. Fungicides were detected in hosts from streams within agricultural watersheds but were not detected in hosts from reference streams. Gut fungi from agricultural sites exhibited decreased percent infestation, density within the gut, and sporulation, and black fly tissues had elevated pesticide concentrations. Differences observed between the sites demonstrate a potential effect on this symbiotic system. Future research is needed to parse out the details of the complex biotic and abiotic relationships; however, these preliminary results indicate that impacts to nontarget organisms could have far-reaching consequences within aquatic ecosystems. PMID:26380545

A Drosophila model for fetal alcohol syndrome disorders: role for the insulin pathway

PubMed Central

McClure, Kimberly D.; French, Rachael L.; Heberlein, Ulrike

2011-01-01

SUMMARY Prenatal exposure to ethanol in humans results in a wide range of developmental abnormalities, including growth deficiency, developmental delay, reduced brain size, permanent neurobehavioral abnormalities and fetal death. Here we describe the use of Drosophila melanogaster as a model for exploring the effects of ethanol exposure on development and behavior. We show that developmental ethanol exposure causes reduced viability, developmental delay and reduced adult body size. We find that flies reared on ethanol-containing food have smaller brains and imaginal discs, which is due to reduced cell division rather than increased apoptosis. Additionally, we show that, as in mammals, flies reared on ethanol have altered responses to ethanol vapor exposure as adults, including increased locomotor activation, resistance to the sedating effects of the drug and reduced tolerance development upon repeated ethanol exposure. We have found that the developmental and behavioral defects are largely due to the effects of ethanol on insulin signaling; specifically, a reduction in Drosophila insulin-like peptide (Dilp) and insulin receptor expression. Transgenic expression of Dilp proteins in the larval brain suppressed both the developmental and behavioral abnormalities displayed by ethanol-reared adult flies. Our results thus establish Drosophila as a useful model system to uncover the complex etiology of fetal alcohol syndrome. PMID:21303840

Thermotaxis, circadian rhythms, and TRP channels in Drosophila

PubMed Central

Bellemer, Andrew

2015-01-01

The fruit fly Drosophila melanogaster is a poikilothermic organism that must detect and respond to both fine and coarse changes in environmental temperature in order maintain optimal body temperature, synchronize behavior to daily temperature fluctuations, and to avoid potentially injurious environmental hazards. Members of the Transient Receptor Potential (TRP) family of cation channels are well known for their activation by changes in temperature and their essential roles in sensory transduction in both invertebrates and vertebrates. The Drosophila genome encodes 13 TRP channels, and several of these have key sensory transduction and modulatory functions in allowing larval and adult flies to make fine temperature discriminations to attain optimal body temperature, detect and avoid large environmental temperature fluctuations, and make rapid escape responses to acutely noxious stimuli. Drosophila use multiple, redundant signaling pathways and neural circuits to execute these behaviors in response to both increases and decreases in temperature of varying magnitudes and time scales. A plethora of powerful molecular and genetic tools and the fly's simple, well-characterized nervous system have given Drosophila neurobiologists a powerful platform to study the cellular and molecular mechanisms of TRP channel function and how these mechanisms are conserved in vertebrates, as well as how these channels function within sensorimotor circuits to generate both simple and complex thermosensory behaviors. PMID:27227026

A role for the membrane protein M6 in the Drosophila visual system.

PubMed

Zappia, María Paula; Bernabo, Guillermo; Billi, Silvia C; Frasch, Alberto C; Ceriani, María Fernanda; Brocco, Marcela Adriana

2012-07-04

Members of the proteolipid protein family, including the four-transmembrane glycoprotein M6a, are involved in neuronal plasticity in mammals. Results from our group previously demonstrated that M6, the only proteolipid protein expressed in Drosophila, localizes to the cell membrane in follicle cells. M6 loss triggers female sterility, which suggests a role for M6 in follicular cell remodeling. These results were the basis of the present study, which focused on the function and requirements of M6 in the fly nervous system. The present study identified two novel, tissue-regulated M6 isoforms with variable N- and C- termini, and showed that M6 is the functional fly ortholog of Gpm6a. In the adult brain, the protein was localized to several neuropils, such as the optic lobe, the central complex, and the mushroom bodies. Interestingly, although reduced M6 levels triggered a mild rough-eye phenotype, hypomorphic M6 mutants exhibited a defective response to light. Based on its ability to induce filopodium formation we propose that M6 is key in cell remodeling processes underlying visual system function. These results bring further insight into the role of M6/M6a in biological processes involving neuronal plasticity and behavior in flies and mammals.

A role for the membrane protein M6 in the Drosophila visual system

PubMed Central

2012-01-01

Background Members of the proteolipid protein family, including the four-transmembrane glycoprotein M6a, are involved in neuronal plasticity in mammals. Results from our group previously demonstrated that M6, the only proteolipid protein expressed in Drosophila, localizes to the cell membrane in follicle cells. M6 loss triggers female sterility, which suggests a role for M6 in follicular cell remodeling. These results were the basis of the present study, which focused on the function and requirements of M6 in the fly nervous system. Results The present study identified two novel, tissue-regulated M6 isoforms with variable N- and C- termini, and showed that M6 is the functional fly ortholog of Gpm6a. In the adult brain, the protein was localized to several neuropils, such as the optic lobe, the central complex, and the mushroom bodies. Interestingly, although reduced M6 levels triggered a mild rough-eye phenotype, hypomorphic M6 mutants exhibited a defective response to light. Conclusions Based on its ability to induce filopodium formation we propose that M6 is key in cell remodeling processes underlying visual system function. These results bring further insight into the role of M6/M6a in biological processes involving neuronal plasticity and behavior in flies and mammals. PMID:22762289

Assessing the potential effects of fungicides on nontarget gut fungi (trichomycetes) and their associated larval black fly hosts

USGS Publications Warehouse

Wilson, Emma R.; Smalling, Kelly L.; Reilly, Timothy J.; Gray, Elmer; Bond, Laura; Steele, Lance; Kandel, Prasanna; Chamberlin, Alison; Gause, Justin; Reynolds, Nicole; Robertson, Ian; Novak, Stephen; Feris, Kevin; White, Merlin M.

2014-01-01

Fungicides are moderately hydrophobic and have been detected in water and sediment, particularly in agricultural watersheds, but typically are not included in routine water quality monitoring efforts. This is despite their widespread use and frequent application to combat fungal pathogens. Although the efficacy of these compounds on fungal pathogens is well documented, little is known about their effects on nontarget fungi. This pilot study, a field survey in southwestern Idaho from April to December 2010 on four streams with varying pesticide inputs (two agricultural and two reference sites), was conducted to assess nontarget impact of fungicides on gut fungi, or trichomycetes. Tissues of larval black flies (Diptera: Simuliidae), hosts of gut fungi, were analyzed for pesticide accumulation. Fungicides were detected in hosts from streams within agricultural watersheds but were not detected in hosts from reference streams. Gut fungi from agricultural sites exhibited decreased percent infestation, density and sporulation within the gut, and black fly tissues had elevated pesticide concentrations. Differences observed between the sites demonstrate a potential effect on this symbiotic system. Future research is needed to parse out the details of the complex biotic and abiotic relationships; however, these preliminary results indicate that impacts to nontarget organisms could have far-reaching consequences within aquatic ecosystems.

The estuarine chemistry and isotope systematics of 234,238U in the Amazon and Fly Rivers

USGS Publications Warehouse

Swarzenski, P.; Campbell, P.; Porcelli, D.; McKee, B.

2004-01-01

Natural concentrations of 238U and ??234U values were determined in estuarine surface waters and pore waters of the Amazon and Fly (Papua New Guinea) Rivers to investigate U transport phenomena across river-dominated land-sea margins. Discharge from large, tropical rivers is a major source of dissolved and solid materials transported to the oceans, and are important in defining not only oceanic mass budgets, but also terrestrial weathering rates. On the Amazon shelf, salinity-property plots of dissolved organic carbon, pH and total suspended matter revealed two vastly contrasting water masses that were energetically mixed. In this mixing zone, the distribution of uranium was highly non-conservative and exhibited extensive removal from the water column. Uranium removal was most pronounced within a salinity range of 0-16.6, and likely the result of scavenging and flocculation reactions with inorganic (i.e., Fe/Mn oxides) and organic colloids/particles. Removal of uranium may also be closely coupled to exchange and resuspension processes at the sediment/water interface. An inner-shelf pore water profile indicated the following diagenetic processes: extensive (???1 m) zones of Fe(III) - and, to a lesser degree, Mn(IV) - reduction in the absence of significant S(II) concentrations appeared to facilitate the formation of various authigenic minerals (e.g., siderite, rhodocrosite and uraninite). The pore water dissolved 238U profile co-varied closely with Mn(II). Isotopic variations as evidenced in ??234U pore waters values from this site revealed information on the origin and history of particulate uranium. Only after a depth of about 1 m did the ??234U value approach unity (secular equilibrium), denoting a residual lattice bound uranium complex that is likely an upper-drainage basin weathering product. This suggests that the enriched ??234U values represent a riverine surface complexation product that is actively involved in Mn-Fe diagenetic cycles and surface complexation reactions. In the Fly River estuary, 238U appears to exhibit a reasonably conservative distribution as a function of salinity. The absence of observed U removal does not necessarily imply non-reactivity, but instead may record an integration of concurrent U removal and release processes. There is not a linear correlation between ??234U vs. 1/ 238U that would imply simple two component mixing. It is likely that resuspension of bottom sediments, prolonged residence times in the lower reaches of the Fly River, and energetic particle-colloid interactions contribute to the observed estuarine U distribution. The supply of uranium discharged from humid, tropical river systems to the sea appears to be foremost influenced by particle/water interactions that are ultimately governed by the particular physiographic and hydrologic characteristics of an estuary. ?? 2004 Elsevier Ltd. All rights reserved.

Managing the horn fly (Diptera: Muscidae) using an electric walk-through fly trap.

PubMed

Watson, D W; Stringham, S M; Denning, S S; Washburn, S P; Poore, M H; Meier, A

2002-10-01

An electric walk-through fly trap was evaluated for the management of the horn fly, Hematobia irritans (L.), on dairy cattle in North Carolina over 2 yr. The trap relies on black lights and electrocution grids to attract and kill flies that are brushed from the cattle passing through. During the first season, horn fly densities were reduced from >1,400 to <200 flies per animal. Horn fly density averaged 269.2 +/- 25.8 on cattle using the walk-through fly trap twice daily, and 400.2 +/- 43.5 on the control group during the first year. The second year, seasonal mean horn fly density was 177.3 +/- 10.8 on cattle using the walk-through fly trap compared with 321.1 +/- 15.8 on the control group. No insecticides were used to control horn flies during this 2-yr study.

Treatment of fly ash for use in concrete

DOEpatents

Boxley, Chett [Park City, UT

2012-05-15

A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with a quantity of spray dryer ash (SDA) and water to initiate a geopolymerization reaction and form a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 40%, and in some cases less than 20%, of the foam index of the untreated fly ash. An optional alkaline activator may be mixed with the fly ash and SDA to facilitate the geopolymerization reaction. The alkaline activator may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

EVALUATING THE EFFECTS OF FLY ASH EXPOSURE ON FISH EARLY LIFE STAGES: FATHEAD MINNOW EMBRYO-LARVAL TESTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greeley Jr, Mark Stephen; Elmore, Logan R; McCracken, Kitty

2012-05-01

On December 22, 2008, a dike containing fly ash and bottom ash in an 84-acre complex of the Tennessee Valley Authority's (TVA) Kingston Steam Plant in East Tennessee failed and released a large quantity of ash into the adjacent Emory River. Ash deposits extended as far as 4 miles upstream (Emory River mile 6) of the Plant, and some ash was carried as far downstream as Tennessee River mile 564 ({approx}4 miles downstream of the Tennessee River confluence with the Clinch River). A byproduct of coal burning power plants, fly ash contains a variety of metals and other elements which,more » at sufficient concentrations and in specific forms, can be toxic to biological systems. The effects of fly ash contamination on exposed fish populations depend on the magnitude and duration of exposure, with the most significant risk considered to be the effects of specific ash constituents, especially selenium, on fish early life stages. Uptake by adult female fish of fly ash constituents through the food chain and subsequent maternal transfer of contaminants to the developing eggs is thought to be the primary route of selenium exposure to larval fish (Woock and others 1987, Coyle and others 1993, Lemly 1999, Moscatello and others 2006), but direct contact of the fertilized eggs and developing embryos to ash constituents in river water and sediments is also a potential risk factor (Woock and others 1987, Coyle and others 1993, Jezierska and others 2009). To address the risk of fly ash from the Kingston spill to the reproductive health of downstream fish populations, ORNL has undertaken a series of studies in collaboration with TVA including: (1) a field study of the bioaccumulation of fly ash constituents in fish ovaries and the reproductive condition of sentinel fish species in reaches of the Emory and Clinch Rivers affected by the fly ash spill; (2) laboratory tests of the potential toxicity of fly ash from the spill area on fish embryonic and larval development (reported in the current technical manuscript); (3) additional laboratory experimentation focused on the potential effects of long-term exposures to fly ash on fish survival and reproductive competence; and (4) a combined field and laboratory study examining the in vitro developmental success of embryos and larvae obtained from fish exposed in vivo for over two years to fly ash in the Emory and Clinch Rivers. These fish reproduction and early life-stage studies are being conducted in conjunction with a broader biological monitoring program administered by TVA that includes a field study of the condition of larval fish in the Emory and Clinch Rivers along with assessments of water quality, sediment composition, ecotoxicological studies, terrestrial wildlife studies, and human and ecological risk assessment. Information and data generated from these studies will provide direct input into risk assessment efforts and will also complement and help support other phases of the overall biomonitoring program. Fish eggs, in general, are known to be capable of concentrating heavy metals and other environmental contaminants from water-borne exposures during embryonic development (Jezierska and others 2009), and fathead minnow embryos in particular have been shown to concentrate methylmercury (Devlin 2006) as well as other chemical toxicants. This technical report focuses on the responses of fathead minnow embryos to simple contact exposures to fly ash in laboratory toxicity tests adapted from a standard fathead minnow (Pimephales promelas) 7-d embryo-larval survival and teratogenicity test (method 1001.0 in EPA 2002) with mortality, hatching success, and the incidences of developmental abnormalities as measured endpoints.« less

"Brown Paper Packages"? A Sociocultural Perspective on Young Children's Ideas in Science

ERIC Educational Resources Information Center

Robbins, Jill

2005-01-01

How do we see young children's thinking in science? Is it, as much previous research has led us to believe, that their ideas can be neatly boxed like "brown paper packages tied up with strings"--as the song from "The Sound of Music" goes? Or are their ideas like "wild geese that fly with the moon on their wings" ("Sound of Music"): fluid, complex,…

Modeling and Simulation Architecture for Studying Doppler-Based Radar with Complex Environments

DTIC Science & Technology

2009-03-26

structures can interfere with a radar’s ability to detect moving aircraft because radar returns from turbines are comparable to those from slow flying...Netherlands Organisation for Applied Scientific Research . 13 EM Electromagnetic . . . . . . . . . . . . . . . . . . . . . . . 14 MTI Moving Target Indicator...ensure the turbine won’t interact with the radar. However, (2.3) doesn’t account for terrain masking or shadowing. If there is a tall object or terrain

Activities commemorating John B. Herrington as first Native American astronaut

NASA Technical Reports Server (NTRS)

2002-01-01

KENNEDY SPACE CENTER, FLA. -- Chickasaw Tribal Elder Lee Frazier leads the dedication to the astronauts of STS-113 during the Native American Ceremony at the Rocket Garden in the KSC Visitor Complex. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

Physics-Based Virtual Fly-Outs of Projectiles on Supercomputers

DTIC Science & Technology

2006-11-01

moved along with its grid as it flew downrange. The supersonic projectile modeled in this study is an ogive- cylinder -finned configuration (see...resulting from the unsteady jet interaction flow field is clearly evident (Figure 10). The effect of the jet is stronger as evidenced by the larger...little or no effect on the other aerodynamic forces. These results show the potential to gain fundamental understanding of the complex, flow

A Layman's Guide to Thrust Engine Development for Super/Hyper Sonic Flight.

ERIC Educational Resources Information Center

Thiesse, James L.

The intention of this paper is to discuss the advances in thrust engines from the initial development of the J58/SR-71 (JT11D-20) of the U.S. Air Force's SR-71 Blackbird to the development of the RAM and SCRAM engines necessary to propel the new generations of high-flying super-speed aircraft. Engineering complexities suggest that the engines and…

Activities commemorating John B. Herrington as first Native American astronaut

NASA Technical Reports Server (NTRS)

2002-01-01

KENNEDY SPACE CENTER, FLA. - Chickasaw Indian princesses 'sign' the Lord's Prayer during a Native American Ceremony at the Rocket Garden in the KSC Visitor Complex. The princesses are Crystal Underwood, Julie Underwood and Tamela Alexander. The ceremony was part of several days' activities commemorating John B. Herrington as the first tribally enrolled Native American astronaut to fly on a Shuttle mission. Herrington is a Mission Specialist on STS-113.

Behavioural system identification of visual flight speed control in Drosophila melanogaster

PubMed Central

Rohrseitz, Nicola; Fry, Steven N.

2011-01-01

Behavioural control in many animals involves complex mechanisms with intricate sensory-motor feedback loops. Modelling allows functional aspects to be captured without relying on a description of the underlying complex, and often unknown, mechanisms. A wide range of engineering techniques are available for modelling, but their ability to describe time-continuous processes is rarely exploited to describe sensory-motor control mechanisms in biological systems. We performed a system identification of visual flight speed control in the fruitfly Drosophila, based on an extensive dataset of open-loop responses previously measured under free flight conditions. We identified a second-order under-damped control model with just six free parameters that well describes both the transient and steady-state characteristics of the open-loop data. We then used the identified control model to predict flight speed responses after a visual perturbation under closed-loop conditions and validated the model with behavioural measurements performed in free-flying flies under the same closed-loop conditions. Our system identification of the fruitfly's flight speed response uncovers the high-level control strategy of a fundamental flight control reflex without depending on assumptions about the underlying physiological mechanisms. The results are relevant for future investigations of the underlying neuromotor processing mechanisms, as well as for the design of biomimetic robots, such as micro-air vehicles. PMID:20525744

Mechanical Design of a 4-Stage ADR for the PIPER mission

NASA Technical Reports Server (NTRS)

James, Bryan L.; Kimball, Mark O.; Shirron, Peter J.; Sampson, Michael A.; Letmate, Richard V.; Jackson, Michael L.

2017-01-01

The four 1,280 bolometer detector arrays that will fly on the balloon borne PIPER mission will be cooled by a 4-stage adiabatic demagnetization refrigerator (ADR). Two of the three mechanically independent ADR assemblies provide thermal isolation to their salt pills through Kevlar suspensions while the other provides thermal isolation to its salt pill through the use of bellows and Vespel material. The ADR integrates with the detector arrays and it sits in a large bucket Dewar containing superfluid liquid helium. This paper will describe the complex mechanical design of the PIPER ADR, and summarize the mechanical analysis done to validate the design.The four 1,280 bolometer detector arrays that will fly on the balloon borne PIPER mission will be cooled by a 4-stage adiabatic demagnetization refrigerator (ADR). Two of the three mechanically independent ADR assemblies provide thermal isolation to their salt pills through Kevlar suspensions while the other provides thermal isolation to its salt pill through the use of bellows and Vespel material. The ADR integrates with the detector arrays and it sits in a large bucket Dewar containing superfluid liquid helium. This paper will describe the complex mechanical design of the PIPER ADR, and summarize the mechanical analysis done to validate the design.

Genetic modifiers of abnormal organelle biogenesis in a Drosophila model of BLOC-1 deficiency

PubMed Central

Cheli, Verónica T.; Daniels, Richard W.; Godoy, Ruth; Hoyle, Diego J.; Kandachar, Vasundhara; Starcevic, Marta; Martinez-Agosto, Julian A.; Poole, Stephen; DiAntonio, Aaron; Lloyd, Vett K.; Chang, Henry C.; Krantz, David E.; Dell'Angelica, Esteban C.

2010-01-01

Biogenesis of lysosome-related organelles complex 1 (BLOC-1) is a protein complex formed by the products of eight distinct genes. Loss-of-function mutations in two of these genes, DTNBP1 and BLOC1S3, cause Hermansky–Pudlak syndrome, a human disorder characterized by defective biogenesis of lysosome-related organelles. In addition, haplotype variants within the same two genes have been postulated to increase the risk of developing schizophrenia. However, the molecular function of BLOC-1 remains unknown. Here, we have generated a fly model of BLOC-1 deficiency. Mutant flies lacking the conserved Blos1 subunit displayed eye pigmentation defects due to abnormal pigment granules, which are lysosome-related organelles, as well as abnormal glutamatergic transmission and behavior. Epistatic analyses revealed that BLOC-1 function in pigment granule biogenesis requires the activities of BLOC-2 and a putative Rab guanine-nucleotide-exchange factor named Claret. The eye pigmentation phenotype was modified by misexpression of proteins involved in intracellular protein trafficking; in particular, the phenotype was partially ameliorated by Rab11 and strongly enhanced by the clathrin-disassembly factor, Auxilin. These observations validate Drosophila melanogaster as a powerful model for the study of BLOC-1 function and its interactions with modifier genes. PMID:20015953

Behavioural system identification of visual flight speed control in Drosophila melanogaster.

PubMed

Rohrseitz, Nicola; Fry, Steven N

2011-02-06

Behavioural control in many animals involves complex mechanisms with intricate sensory-motor feedback loops. Modelling allows functional aspects to be captured without relying on a description of the underlying complex, and often unknown, mechanisms. A wide range of engineering techniques are available for modelling, but their ability to describe time-continuous processes is rarely exploited to describe sensory-motor control mechanisms in biological systems. We performed a system identification of visual flight speed control in the fruitfly Drosophila, based on an extensive dataset of open-loop responses previously measured under free flight conditions. We identified a second-order under-damped control model with just six free parameters that well describes both the transient and steady-state characteristics of the open-loop data. We then used the identified control model to predict flight speed responses after a visual perturbation under closed-loop conditions and validated the model with behavioural measurements performed in free-flying flies under the same closed-loop conditions. Our system identification of the fruitfly's flight speed response uncovers the high-level control strategy of a fundamental flight control reflex without depending on assumptions about the underlying physiological mechanisms. The results are relevant for future investigations of the underlying neuromotor processing mechanisms, as well as for the design of biomimetic robots, such as micro-air vehicles.

Ear-body lift and a novel thrust generating mechanism revealed by the complex wake of brown long-eared bats (Plecotus auritus)

NASA Astrophysics Data System (ADS)

Johansson, L. Christoffer; Håkansson, Jonas; Jakobsen, Lasse; Hedenström, Anders

2016-04-01

Large ears enhance perception of echolocation and prey generated sounds in bats. However, external ears likely impair aerodynamic performance of bats compared to birds. But large ears may generate lift on their own, mitigating the negative effects. We studied flying brown long-eared bats, using high resolution, time resolved particle image velocimetry, to determine the aerodynamics of flying with large ears. We show that the ears and body generate lift at medium to cruising speeds (3-5 m/s), but at the cost of an interaction with the wing root vortices, likely reducing inner wing performance. We also propose that the bats use a novel wing pitch mechanism at the end of the upstroke generating thrust at low speeds, which should provide effective pitch and yaw control. In addition, the wing tip vortices show a distinct spiraling pattern. The tip vortex of the previous wingbeat remains into the next wingbeat and rotates together with a newly formed tip vortex. Several smaller vortices, related to changes in circulation around the wing also spiral the tip vortex. Our results thus show a new level of complexity in bat wakes and suggest large eared bats are less aerodynamically limited than previous wake studies have suggested.

Role of insects in the transmission of bovine leukosis virus: potential for transmission by stable flies, horn flies, and tabanids.

PubMed

Buxton, B A; Hinkle, N C; Schultz, R D

1985-01-01

The ability of stable flies (Stomoxys calcitrans), horn flies (Haematobia irritans), and tabanids (Diptera: Tabanidae) to transmit bovine leukosis virus (BLV) was investigated. Stable flies and horn flies were fed on blood collected from an infected cow, and the flies' mouthparts were immediately removed, placed in RPMI-1640 medium, ground, and inoculated into sheep and calves. Infection of sheep occurred with mouthparts from as few as 25 stable flies or 25 horn flies. However, sheep were not infected when removal of stable fly mouthparts was delayed greater than or equal to 1 hour after blood feeding. Infection of calves occurred after inoculation of mouthparts removed immediately after feeding from as few as 50 stable flies or 100 horn flies. Infected blood, applied by capillary action to the mouthparts (labella) of 15 deer flies (Chrysops sp) and a single horse fly (Tabanus atratus) caused infection in each of 2 sheep. Infection did not occur in 2 calves inoculated daily for 5 days with mouthparts from 50 horn flies collected after feeding on a BLV-infected steer. Four calves receiving bites from 75 stable flies interrupted from feeding on a BLV-positive cow also were not infected. Seronegative cattle held for 1 to 4 months in a screened enclosure with positive cattle in the presence of biting flies were not infected with BLV. The feeding behavior of each insect is discussed to assess their potential as vectors of BLV.

Recent "Ground Testing" Experiences in the National Full-Scale Aerodynamics Complex

NASA Technical Reports Server (NTRS)

Zell, Peter; Stich, Phil; Sverdrup, Jacobs; George, M. W. (Technical Monitor)

2002-01-01

The large test sections of the National Full-scale Aerodynamics Complex (NFAC) wind tunnels provide ideal controlled wind environments to test ground-based objects and vehicles. Though this facility was designed and provisioned primarily for aeronautical testing requirements, several experiments have been designed to utilize existing model mount structures to support "non-flying" systems. This presentation will discuss some of the ground-based testing capabilities of the facility and provide examples of groundbased tests conducted in the facility to date. It will also address some future work envisioned and solicit input from the SATA membership on ways to improve the service that NASA makes available to customers.

Considerations on the Species Complex of the Cortelezzii series (Diptera: Psychodidae) and Description of Evandromyia chacuensis sp. nov., a New Phlebotomine Species of the Chaco Region, Argentina.

PubMed

Szelag, Enrique A; Rosa, Juan R; Galati, Eunice A B; Andrade Filho, José D; Salomón, Oscar D

2018-04-06

A new species of phlebotomine sand fly is described and illustrated based on male and female specimens collected in rural and semi-urban areas of the Chaco Province, Argentina. A separation of the Cortelezzii series in two species complexes is proposed, as is a species key for its identification. The morphological characters of the new species permit its inclusion in the Cortelezzii series of genus Evandromyia, subgenus Barrettomyia (Diptera: Psychodidae). The species is named Evandromyia chacuensis sp. nov. Szelag, Rosa, Galati, Andrade Fhilo & Salomón (Diptera: Psychodidae).

Experiments in Nonlinear Adaptive Control of Multi-Manipulator, Free-Flying Space Robots

NASA Technical Reports Server (NTRS)

Chen, Vincent Wei-Kang

1992-01-01

Sophisticated robots can greatly enhance the role of humans in space by relieving astronauts of low level, tedious assembly and maintenance chores and allowing them to concentrate on higher level tasks. Robots and astronauts can work together efficiently, as a team; but the robot must be capable of accomplishing complex operations and yet be easy to use. Multiple cooperating manipulators are essential to dexterity and can broaden greatly the types of activities the robot can achieve; adding adaptive control can ease greatly robot usage by allowing the robot to change its own controller actions, without human intervention, in response to changes in its environment. Previous work in the Aerospace Robotics Laboratory (ARL) have shown the usefulness of a space robot with cooperating manipulators. The research presented in this dissertation extends that work by adding adaptive control. To help achieve this high level of robot sophistication, this research made several advances to the field of nonlinear adaptive control of robotic systems. A nonlinear adaptive control algorithm developed originally for control of robots, but requiring joint positions as inputs, was extended here to handle the much more general case of manipulator endpoint-position commands. A new system modelling technique, called system concatenation was developed to simplify the generation of a system model for complicated systems, such as a free-flying multiple-manipulator robot system. Finally, the task-space concept was introduced wherein the operator's inputs specify only the robot's task. The robot's subsequent autonomous performance of each task still involves, of course, endpoint positions and joint configurations as subsets. The combination of these developments resulted in a new adaptive control framework that is capable of continuously providing full adaptation capability to the complex space-robot system in all modes of operation. The new adaptive control algorithm easily handles free-flying systems with multiple, interacting manipulators, and extends naturally to even larger systems. The new adaptive controller was experimentally demonstrated on an ideal testbed in the ARL-A first-ever experimental model of a multi-manipulator, free-flying space robot that is capable of capturing and manipulating free-floating objects without requiring human assistance. A graphical user interface enhanced the robot usability: it enabled an operator situated at a remote location to issue high-level task description commands to the robot, and to monitor robot activities as it then carried out each assignment autonomously.

Discovery, Development, and Evaluation of a Horn Fly-Isolated (Diptera: Muscidae) Beauveria bassiana (Hypocreales: Cordyciptaceae) Strain From Florida, USA

PubMed Central

Holderman, Christopher J.; Wood, Lois A.; Geden, Christopher J.

2017-01-01

The horn fly, Haematobia irritans (L.) is an important cattle pest and traditionally has been managed using insecticides; however, many horn fly populations are insecticide-resistant in United States. Use of alternative control techniques has been limited because of the challenges of managing a fly pest on pastured cattle. After the discovery of a wild horn fly infected with Beauveria bassiana in Florida, the fungus was cultured and evaluated for efficacy against laboratory-reared horn flies. This fungal strain was selected for increased virulence by passage through laboratory-reared horn fly hosts to shorten interval from infection to fly death and subsequent conidia formation, properties important to future use of the fungus as a biological control agent against horn flies. After seven passages through horn fly hosts, fly mortality was not significantly accelerated as evaluated through LT50 values, but conidia were readily produced from these killed flies. Although further development is needed to improve fungal efficacy, this fungal strain holds promise as a biological control agent for inclusion in horn fly integrated pest management programs. PMID:28423414

CO.sub.2 utilization in electrochemical systems

DOEpatents

Boxley, Chett; Akash, Akash; Zhao, Qiang

2013-01-22

A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with a quantity of spray dryer ash (SDA) and water to initiate a geopolymerization reaction and form a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 40%, and in some cases less than 20%, of the foam index of the untreated fly ash. An optional alkaline activator may be mixed with the fly ash and SDA to facilitate the geopolymerization reaction. The alkaline activator may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

The role of experience in flight behaviour of Drosophila.

PubMed

Hesselberg, Thomas; Lehmann, Fritz-Olaf

2009-10-01

Experience plays a key role in the acquisition of complex motor skills in running and flight of many vertebrates. To evaluate the significance of previous experience for the efficiency of motor behaviour in an insect, we investigated the flight behaviour of the fruit fly Drosophila. We reared flies in chambers in which the animals could freely walk and extend their wings, but could not gain any flight experience. These naive animals were compared with control flies under both open- and closed-loop tethered flight conditions in a flight simulator as well as in a free-flight arena. The data suggest that the overall flight behaviour in Drosophila seems to be predetermined because both groups exhibited similar mean stroke amplitude and stroke frequency, similar open-loop responses to visual stimulation and the immediate ability to track visual objects under closed-loop feedback conditions. In short free flight bouts, peak saccadic turning rate, angular acceleration, peak horizontal speed and flight altitude were also similar in naive and control flies. However, we found significant changes in other key parameters in naive animals such as a reduction in mean horizontal speed (-23%) and subtle changes in mean turning rate (-48%). Naive flies produced 25% less yaw torque-equivalent stroke amplitudes than the controls in response to a visual stripe rotating in open loop around the tethered animal, potentially suggesting a flight-dependent adaptation of the visuo-motor gain in the control group. This change ceased after the animals experienced visual closed-loop feedback. During closed-loop flight conditions, naive flies had 53% larger differences in left and right stroke amplitude when fixating a visual object, thus steering control was less precise. We discuss two alternative hypotheses to explain our results: the ;neuronal experience' hypothesis, suggesting that there are some elements of learning and fine-tuning involved during the first flight experiences in Drosophila and the ;muscular exercise' hypothesis. Our experiments support the first hypothesis because maximum locomotor capacity seems not to be significantly impaired in the naive group. Although this study primarily confirms the genetic pre-disposition for flight in Drosophila, previous experience may apparently adjust locomotor fine control and aerial performance, although this effect seems to be small compared with vertebrates.

Biology, taxonomy, and IPM strategies of Bactrocera tau Walker and complex species (Diptera; Tephritidae) in Asia: a comprehensive review.

PubMed

Jaleel, Waqar; Lu, Lihua; He, Yurong

2018-06-02

Bactrocera flies are the serious pests of fruit, vegetables, and nuts over the world. Bactrocera tau Walker is an economically important pest of agricultural crops. In Asia, approximately 30-40% losses of agricultural products are caused by B. tau infestation every year. In Asia, the B. tau contains a complex of sibling species that called the tau complex. However, the basic studies of B. tau and complex species are very important for integrated management. A comprehensive review of the B. tau and complex species has not been provided elsewhere. So, considering the importance of B. tau and complex species, this study provides the published information on ecology, nomenclature, identification tools, geographical distribution, potential invasion, and IPM tactics of B. tau and complex species, which would be more informative for publication facilitating related to integrated pest management (IPM) strategies of B. tau and complex species. In IPM of B. tau and complex species, the phytochemical and biological controls have not been applied successfully in Asia; there is an urgent need to study and applications of these two mentioned control techniques against the B. tau and complex species in Asia.

Flight Capacity of the Walnut Twig Beetle (Coleoptera: Scolytidae) on a Laboratory Flight Mill.

PubMed

Kees, Aubree M; Hefty, Andrea R; Venette, Robert C; Seybold, Steven J; Aukema, Brian H

2017-06-01

The walnut twig beetle, Pityophthorus juglandis Blackman, and associated fungus Geosmithia morbida Kolařík, Freeland, Utley, & Tisserat constitute the insect-fungal complex that causes thousand cankers disease in walnut, Juglans spp., and wingnut, Pterocarya spp. Thousand cankers disease is responsible for the decline of Juglans species throughout the western United States and more recently, the eastern United States and northern Italy. We examined the flight capacity of P. juglandis over 24-h trials on a flight mill in the laboratory. The maximum total flight distance observed was ∼3.6 km in 24 h; however, the mean and median distances flown by beetles that initiated flight were ∼372 m and ∼158 m, respectively. Beetles flew for 34 min on average within a 24-h flight trial. Male and female flight capacities were similar, even though males were larger than females (0.64 vs. 0.57 mm pronotal width). Age postemergence had no effect on flight distance, flight time, or mean flight velocity. The propensity to fly, however, decreased with age. We integrated results of flight distance with propensity to fly as beetles aged in a Monte Carlo simulation to estimate the maximum dispersal capacity over 5 d, assuming no mortality. Only 1% of the insects would be expected to fly >2 km, whereas one-third of the insects were estimated to fly <100 m. These results suggest that nascent establishments remain relatively localized without anthropogenic transport or wind-aided dispersal, which has implications for management and sampling of this hardwood pest. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

Upwash exploitation and downwash avoidance by flap phasing in ibis formation flight.

PubMed

Portugal, Steven J; Hubel, Tatjana Y; Fritz, Johannes; Heese, Stefanie; Trobe, Daniela; Voelkl, Bernhard; Hailes, Stephen; Wilson, Alan M; Usherwood, James R

2014-01-16

Many species travel in highly organized groups. The most quoted function of these configurations is to reduce energy expenditure and enhance locomotor performance of individuals in the assemblage. The distinctive V formation of bird flocks has long intrigued researchers and continues to attract both scientific and popular attention. The well-held belief is that such aggregations give an energetic benefit for those birds that are flying behind and to one side of another bird through using the regions of upwash generated by the wings of the preceding bird, although a definitive account of the aerodynamic implications of these formations has remained elusive. Here we show that individuals of northern bald ibises (Geronticus eremita) flying in a V flock position themselves in aerodynamically optimum positions, in that they agree with theoretical aerodynamic predictions. Furthermore, we demonstrate that birds show wingtip path coherence when flying in V positions, flapping spatially in phase and thus enabling upwash capture to be maximized throughout the entire flap cycle. In contrast, when birds fly immediately behind another bird--in a streamwise position--there is no wingtip path coherence; the wing-beats are in spatial anti-phase. This could potentially reduce the adverse effects of downwash for the following bird. These aerodynamic accomplishments were previously not thought possible for birds because of the complex flight dynamics and sensory feedback that would be required to perform such a feat. We conclude that the intricate mechanisms involved in V formation flight indicate awareness of the spatial wake structures of nearby flock-mates, and remarkable ability either to sense or predict it. We suggest that birds in V formation have phasing strategies to cope with the dynamic wakes produced by flapping wings.

Chromosomal Translocations in Black Flies (Diptera: Simuliidae)-Facilitators of Adaptive Radiation?

PubMed

Adler, Peter H; Yadamsuren, Oyunchuluun; Procunier, William S

2016-01-01

A macrogenomic investigation of a Holarctic clade of black flies-the Simulium cholodkovskii lineage-provided a platform to explore the implications of a unique, synapomorphic whole-arm interchange in the evolution of black flies. Nearly 60 structural rearrangements were discovered in the polytene complement of the lineage, including 15 common to all 138 analyzed individuals, relative to the central sequence for the entire subgenus Simulium. Three species were represented, of which two Palearctic entities (Simulium cholodkovskii and S. decimatum) were sympatric; an absence of hybrids confirmed their reproductive isolation. A third (Nearctic) entity had nonhomologous sex chromosomes, relative to the other species, and is considered a separate species, for which the name Simulium nigricoxum is revalidated. A cytophylogeny is inferred and indicates that the two Palearctic taxa are sister species and these, in turn, are the sister group of the Nearctic species. The rise of the S. cholodkovskii lineage encompassed complex chromosomal and genomic restructuring phenomena associated with speciation in black flies, viz. expression of one and the same rearrangement as polymorphic, fixed, or sex linked in different species; taxon-specific differentiation of sex chromosomes; and reciprocal translocation of chromosome arms. The translocation is hypothesized to have occurred early in male spermatogonia, with the translocated chromosomal complement being transmitted to the X- and Y-bearing sperm during spermatogenesis, resulting in alternate disjunction of viable F1 translocation heterozygotes and the eventual formation of more viable and selectable F2 translocation homozygous progeny. Of 11 or 12 independently derived whole-arm interchanges known in the family Simuliidae, at least six are associated with subsequent speciation events, suggesting a facilitating role of translocations in adaptive radiations. The findings are discussed in the context of potential structural and functional interactions for future genomic research.

Optimization of total vaporization solid-phase microextraction (TV-SPME) for the determination of lipid profiles of Phormia regina, a forensically important blow fly species.

PubMed

Kranz, William; Carroll, Clinton; Dixon, Darren; Picard, Christine; Goodpaster, John

2017-11-01

A new method has been developed for the determination of fatty acids, sterols, and other lipids which naturally occur within pupae of the blow fly Phormia regina. The method relies upon liquid extraction in non-polar solvent, followed by derivatization using N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) w/ 1% trimethylchlorsilane (TMCS) carried out inside the sample vial. The analysis is facilitated by total vaporization solid-phase microextraction (TV-SPME), with gas chromatography-mass spectrometry (GC-MS) serving as the instrumentation for analysis. The TV-SPME delivery technique is approximately a factor of five more sensitive than traditional liquid injection, which may alleviate the need for rotary evaporation, reconstitution, collection of high performance liquid chromatography fractions, and many of the other pre-concentration steps that are commonplace in the current literature. Furthermore, the ability to derivatize the liquid extract in a single easy step while increasing sensitivity represents an improvement over current derivatization methods. The most common lipids identified in fly pupae were various saturated and unsaturated fatty acids ranging from lauric acid (12:0) to arachinoic acid (20:4), as well as cholesterol. The concentrations of myristic acid (14:0), palmitelaidic acid (16:2), and palmitoleic acid (16:1) were the most reliable indicators of the age of the pupae. Graphical abstract Blow fly pupae were extracted prior to emerging as adults. The extracts were analyzed via total vaporization solid-phase microextraction (TV-SPME), revealing a complex mixture of lipids that could be associated with the age of the insect. This information may assist in determining a post-mortum interval (PMI) in a death investigation.

Sexual selection in true fruit flies (Diptera: Tephritidae): transcriptome and experimental evidences for phytochemicals increasing male competitive ability.

PubMed

Kumaran, Nagalingam; Prentis, Peter J; Mangalam, Kalimuthu P; Schutze, Mark K; Clarke, Anthony R

2014-09-01

In male tephritid fruit flies of the genus Bactrocera, feeding on secondary plant compounds (sensu lato male lures = methyl eugenol, raspberry ketone and zingerone) increases male mating success. Ingested male lures alter the male pheromonal blend, normally making it more attractive to females and this is considered the primary mechanism for the enhanced mating success. However, the male lures raspberry ketone and zingerone are known, across a diverse range of other organisms, to be involved in increasing energy metabolism. If this also occurs in Bactrocera, then this may represent an additional benefit to males as courtship is metabolically expensive and lure feeding may increase a fly's short-term energy. We tested this hypothesis by performing comparative RNA-seq analysis between zingerone-fed and unfed males of Bactrocera tryoni. We also carried out behavioural assays with zingerone- and cuelure-fed males to test whether they became more active. RNA-seq analysis revealed, in zingerone-fed flies, up-regulation of 3183 genes with homologues transcripts to those known to regulate intermale aggression, pheromone synthesis, mating and accessory gland proteins, along with significant enrichment of several energy metabolic pathways and gene ontology terms. Behavioural assays show significant increases in locomotor activity, weight reduction and successful mating after mounting; all direct/indirect measures of increased activity. These results suggest that feeding on lures leads to complex physiological changes, which result in more competitive males. These results do not negate the pheromone effect, but do strongly suggest that the phytochemical-induced sexual selection is governed by both female preference and male competitive mechanisms. © 2014 John Wiley & Sons Ltd.

Bats Use Path Integration Rather Than Acoustic Flow to Assess Flight Distance along Flyways.

PubMed

Aharon, Gal; Sadot, Meshi; Yovel, Yossi

2017-12-04

Navigation can be achieved using different strategies from simple beaconing to complex map-based movement [1-4]. Bats display remarkable navigation capabilities, ranging from nightly commutes of several kilometers and up to seasonal migrations over thousands of kilometers [5]. Many bats have been suggested to fly along fixed routes termed "flyways," when flying from their roost to their foraging sites [6]. Flyways commonly stretch along linear landscape elements such as tree lines, hedges, or rivers [7]. When flying along a flyway, bats must estimate the distance they have traveled in order to determine when to turn. This can be especially challenging when moving along a repetitive landscape. Some bats, like Kuhl's pipistrelles, which we studied here, have limited vision [8] and were suggested to rely on bio-sonar for navigation. These bats could therefore estimate distance using three main sensory-navigation strategies, all of which we have examined: acoustic flow, acoustic landmarks, or path integration. We trained bats to fly along a linear flyway and land on a platform. We then tested their behavior when the platform was removed under different manipulations, including changing the acoustic flow, moving the start point, and adding wind. We found that bats do not require acoustic flow, which was hypothesized to be important for their navigation [9-15], and that they can perform the task without landmarks. Our results suggest that Kuhl's pipistrelles use internal self-motion cues-also known as path integration-rather than external information to estimate flight distance for at least dozens of meters when navigating along linear flyways. Copyright © 2017 Elsevier Ltd. All rights reserved.

Station-Keeping Strategies for Lead-Trail Formation Flying

NASA Astrophysics Data System (ADS)

Martinot, V.; Rozanes, P.

Numerous projects in the Science and Observation domains involve the use of formation flying to ensure the mission performance. The formation flying configurations proposed in some of them are quite complex with several satellites in different planes generating relative differential motions between the satellites like in case of circular projected formation-flying. However, more simple designs consisting of two satellites in a lead-trail formation appear to be sufficient for a wide range of applications (interferometry, geodesy,...). This article concentrates on the station- keeping phase of such formations in Low-Earth Orbits The station-keeping criterion for such formations can be expressed for example in terms of difference in argument of latitude between both satellites and at the altitudes considered, it evolves mainly under the differential effect of the atmospheric drag between the trailing and leading satellites. In the present paper, this differential effect is supposed to originate from the difference in the area-to-mass ratio between the satellites due to their different designs. A preliminary estimation of the navigation performance is first given assuming that on-board GPS receiver are mounted on each satellite of the formation to acquire pseudo-range measurements between the LEO satellites and the MEO GPS constellation. The distance between both satellites of the formation is derived from independent orbit restitution performed for each LEO satellite in a ground master control station processing the GPS measurements. A strategy for controlling the satellite formation disturbed by the differential effect of the drag is then proposed. Simulations are performed to assess the feasibility of the station-keeping with different types of engines. As by-products, the propellant budget and the frequency of the station-keeping manoeuvres are also given. A case study inspired from the ESA project Acechem/Metop is used for the simulations.

Late winter and early spring home range and habitat use of the endangered Carolina northern flying squirrel in western North Carolina

USGS Publications Warehouse

Ford, W. Mark; Kelly, Christine A.; Rodrigue, Jane L.; Odom, Richard H.; Newcomb, Douglas; Gilley, L. Michelle; Diggins, Corinne A.

2014-01-01

The Carolina northern flying squirrel Glaucomys sabrinus coloratus is an endangered subspecies that is restricted to high elevation forests in the southern Appalachian Mountains. Owing to rugged terrain and nocturnal habits, the subspecies’ natural history, home range characteristics and habitat preferences are poorly known. We radio-tracked 3 female and 2 male Carolina northern flying squirrels during late winter through spring 2012 in the Pisgah National Forest, North Carolina, USA. Tracked squirrels used 13 yellow birch Betula alleghaniensis and 9 red spruce Picea rubens as diurnal dens. Ten of the yellow birch dens were in cavities, whereas the remainders were dreys. Conversely, 8 of the red spruce dens were dreys and one was in a cavity. Mean (±SE) female 95 and 50% adaptive kernel home ranges were 6.50 ± 2.19 and 0.93 ± 0.33 ha, respectively, whereas the corresponding values for males were 12.6 ± 0.9 and 1.45 ± 0.1 ha, respectively. Squirrels used red spruce stands with canopies >20 m more than expected based on availability at the landscape and home range scales. Results should be interpreted cautiously because of small sample sizes and seasonal observations; however, they provide evidence that although northern hardwoods such as yellow birch are an important den habitat component, mature red spruce-dominated habitats with complex structure provide foraging habitats and are also den habitat. Our findings support efforts to improve the structural condition of extant red spruce forests and/or increase red spruce acreage to potentially benefit Carolina northern flying squirrels.

Study on Strength Behavior of Organic Soil Stabilized with Fly Ash

PubMed Central

Molla, Md. Keramat Ali; Sarkar, Grytan

2017-01-01

The aim of this study is to investigate the effect of fly ash on the consistency, compactness, acidic properties, and strength of organic soil. The presence of organic content in the soil has detrimental impacts on the physical and strength behavior of soil. To investigate the effectiveness of fly ash in the stabilization of organic soil, two types of fly ashes (Type I and Type II) at different percentages were used. It is found that fly ash significantly reduces the plasticity index of the organic soil, whereas the liquid and plastic limits increase. The dry density of the fly ash-soil mixture increases significantly, while the water requirement reduces due to the addition of fly ash. The increase of dry density compromises higher strength. The increase of qu with the increase of fly ash content is mainly due to the pozzolanic reaction of fly ash, although the reduction in water content results from the addition of dry fly ash solid. Moreover, Type I fly ash contributes a higher value of qu compared to Type II fly ash. This is attributed to the characteristics of fly ash including CaO and CaO/SiO2 ratio. PMID:29085881

Cross-Study Comparison Reveals Common Genomic, Network, and Functional Signatures of Desiccation Resistance in Drosophila melanogaster

PubMed Central

Telonis-Scott, Marina; Sgrò, Carla M.; Hoffmann, Ary A.; Griffin, Philippa C.

2016-01-01

Repeated attempts to map the genomic basis of complex traits often yield different outcomes because of the influence of genetic background, gene-by-environment interactions, and/or statistical limitations. However, where repeatability is low at the level of individual genes, overlap often occurs in gene ontology categories, genetic pathways, and interaction networks. Here we report on the genomic overlap for natural desiccation resistance from a Pool-genome-wide association study experiment and a selection experiment in flies collected from the same region in southeastern Australia in different years. We identified over 600 single nucleotide polymorphisms associated with desiccation resistance in flies derived from almost 1,000 wild-caught genotypes, a similar number of loci to that observed in our previous genomic study of selected lines, demonstrating the genetic complexity of this ecologically important trait. By harnessing the power of cross-study comparison, we narrowed the candidates from almost 400 genes in each study to a core set of 45 genes, enriched for stimulus, stress, and defense responses. In addition to gene-level overlap, there was higher order congruence at the network and functional levels, suggesting genetic redundancy in key stress sensing, stress response, immunity, signaling, and gene expression pathways. We also identified variants linked to different molecular aspects of desiccation physiology previously verified from functional experiments. Our approach provides insight into the genomic basis of a complex and ecologically important trait and predicts candidate genetic pathways to explore in multiple genetic backgrounds and related species within a functional framework. PMID:26733490

Flare cue symbology and EVS for zero-zero weather landing

NASA Astrophysics Data System (ADS)

French, Guy A.; Murphy, David M.; Ercoline, William R.

2006-05-01

When flying an airplane, landing is arguably the most difficult task a pilot can do. This applies to pilots of all skill levels particularly as the level of complexity in both the aircraft and environment increase. Current navigational aids, such as an instrument landing system (ILS), do a good job of providing safe guidance for an approach to an airfield. These aids provide data to primary flight reference (PFR) displays on-board the aircraft depicting through symbology what the pilot's eyes should be seeing. Piloting an approach under visual meteorological conditions (VMC) is relatively easy compared to the various complex instrument approaches under instrument meteorological conditions (IMC) which may include flying in zero-zero weather. Perhaps the most critical point in the approach is the transition to landing where the rate of closure between the wheels and the runway is critical to a smooth, accurate landing. Very few PFR's provide this flare cue information. In this study we will evaluate examples of flare cueing symbology for use in landing an aircraft in the most difficult conditions. This research is a part of a larger demonstration effort using sensor technology to land in zero-zero weather at airfields that offer no or unreliable approach guidance. Several problems exist when landing without visual reference to the outside world. One is landing with a force greater than desired at touchdown and another is landing on a point of the runway other than desired. We compare different flare cueing systems to one another and against a baseline for completing this complex approach task.

Planar Cell Polarity Breaks the Symmetry of PAR Protein Distribution prior to Mitosis in Drosophila Sensory Organ Precursor Cells.

PubMed

Besson, Charlotte; Bernard, Fred; Corson, Francis; Rouault, Hervé; Reynaud, Elodie; Keder, Alyona; Mazouni, Khalil; Schweisguth, François

2015-04-20

During development, cell-fate diversity can result from the unequal segregation of fate determinants at mitosis. Polarization of the mother cell is essential for asymmetric cell division (ACD). It often involves the formation of a cortical domain containing the PAR complex proteins Par3, Par6, and atypical protein kinase C (aPKC). In the fly notum, sensory organ precursor cells (SOPs) divide asymmetrically within the plane of the epithelium and along the body axis to generate two distinct cells. Fate asymmetry depends on the asymmetric localization of the PAR complex. In the absence of planar cell polarity (PCP), SOPs divide with a random planar orientation but still asymmetrically, showing that PCP is dispensable for PAR asymmetry at mitosis. To study when and how the PAR complex localizes asymmetrically, we have used a quantitative imaging approach to measure the planar polarization of the proteins Bazooka (Baz, fly Par3), Par6, and aPKC in living pupae. By using imaging of functional GFP-tagged proteins with image processing and computational modeling, we find that Baz, Par6, and aPKC become planar polarized prior to mitosis in a manner independent of the AuroraA kinase and that PCP is required for the planar polarization of Baz, Par6, and aPKC during interphase. This indicates that a "mitosis rescue" mechanism establishes asymmetry at mitosis in PCP mutants. This study therefore identifies PCP as the initial symmetry-breaking signal for the planar polarization of PAR proteins in asymmetrically dividing SOPs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Experimental and field investigation of non-biting flies as potential mechanical vectors of Echinococcus granulosus eggs.

PubMed

Hemmati, Sahel; Afshar, Abbas Aghaei; Mohammadi, Mohammad Ali; Afgar, Ali; Nasibi, Saeid; Harandi, Majid Fasihi

2018-06-01

Synanthropic fly species can be potential mechanical vectors of many infectious agents. The potential of the flies to carry Echinococcus granulosus eggs is not fully documented. The purpose of the present study was to determine the possible role of non-biting flies to carry taeniid eggs. A total of 210 flies were collected from seven selected sites in areas of Kerman city, southeastern Iran from November 2016 to May 2017. Adult flies were live-caught using sweeping nets. Flies were placed individually in small glass bottles and transported to the laboratory. All the flies were killed by deep freezing and then identified to the species level using both morphological and molecular methods. The flies were homogenized in test tubes and genomic DNA was extracted and amplified by PCR. PCR protocols were used both to identify the live-caught flies to the species level, and for the detection of E. granulosus. The laboratory reared second generation flies were experimentally exposed to dog feces manually spiked by Echinococcus eggs. Two runs of experiments with 1-3 h of exposure were designed. For each experiment 20 flies were selected from the stock colony and were starved for three days. After each experiment, the flies were frozen for further molecular studies. The dominant fly species were Musca domestica and Lucilia sericata. No eggs were found on the body surface and/or guts of live-caught flies. After the first hour of exposure, 60%, of the flies of both species were found to harbor Echinococcus eggs. However, in the case of L. sericata 50% of the flies harbored Echinococcus eggs after 3 h of exposure. Results of the present study indicate the probable role of synanthropic flies in harboring Echinococcus eggs and mechanical transmission of cystic echinococcosis. When the helminth eggs are susceptible to desiccation grooming flies can remove many of eggs from exterior surfaces of them. Despite this result the role of synanthropic flies in the transmission of certain helminthiases should not be discounted because of their vagility and feeding mechanisms. Copyright © 2018 Elsevier Inc. All rights reserved.

Properties of Fly Ash Blocks Made from Adobe Mould

NASA Astrophysics Data System (ADS)

Chokhani, Alankrit; Divakar, B. S.; Jawalgi, Archana S.; Renukadevi, M. V.; Jagadish, K. S.

2018-02-01

Fly ash being one of the industrial waste products poses a serious disposal problem. This paper presents an experimental study of utilization of fly ash to produce blocks with varying proportions and mix combinations. Composition of fly ash blocks mainly consist of fly ash and sand, with cementitious product as either cement, lime or both, such as fly ash-sand-cement, fly ash-sand-lime and fly ash-sand-cement-lime are used. Four different proportions for each of the mix combinations are experimented. Compressive strength, water absorption, Initial rate of absorption, and dry density of fly ash blocks are studied. The influence of partial and complete replacement of cement by lime is examined.

Properties of Fly Ash Blocks Made from Adobe Mould

NASA Astrophysics Data System (ADS)

Chokhani, Alankrit; Divakar, B. S.; Jawalgi, Archana S.; Renukadevi, M. V.; Jagadish, K. S.

2018-06-01

Fly ash being one of the industrial waste products poses a serious disposal problem. This paper presents an experimental study of utilization of fly ash to produce blocks with varying proportions and mix combinations. Composition of fly ash blocks mainly consist of fly ash and sand, with cementitious product as either cement, lime or both, such as fly ash-sand-cement, fly ash-sand-lime and fly ash-sand-cement-lime are used. Four different proportions for each of the mix combinations are experimented. Compressive strength, water absorption, Initial rate of absorption, and dry density of fly ash blocks are studied. The influence of partial and complete replacement of cement by lime is examined.

Evaluation of surveillance methods for monitoring house fly abundance and activity on large commercial dairy operations.

PubMed

Gerry, Alec C; Higginbotham, G E; Periera, L N; Lam, A; Shelton, C R

2011-06-01

Relative house fly, Musca domestica L., activity at three large dairies in central California was monitored during the peak fly activity period from June to August 2005 by using spot cards, fly tapes, bait traps, and Alsynite traps. Counts for all monitoring methods were significantly related at two of three dairies; with spot card counts significantly related to fly tape counts recorded the same week, and both spot card counts and fly tape counts significantly related to bait trap counts 1-2 wk later. Mean fly counts differed significantly between dairies, but a significant interaction between dairies sampled and monitoring methods used demonstrates that between-dairy comparisons are unwise. Estimate precision was determined by the coefficient of variability (CV) (or SE/mean). Using a CV = 0.15 as a desired level of estimate precision and assuming an integrate pest management (IPM) action threshold near the peak house fly activity measured by each monitoring method, house fly monitoring at a large dairy would require 12 spot cards placed in midafternoon shaded fly resting sites near cattle or seven bait traps placed in open areas near cattle. Software (FlySpotter; http://ucanr.org/ sites/FlySpotter/download/) using computer vision technology was developed to count fly spots on a scanned image of a spot card to dramatically reduce time invested in monitoring house flies. Counts provided by the FlySpotter software were highly correlated to visual counts. The use of spot cards for monitoring house flies is recommended for dairy IPM programs.

Blood feeding behavior of the stable fly

USDA-ARS?s Scientific Manuscript database

Stable fly is a fly that looks similar to a house fly but both sexes are blood feeders. Blood is required for successful fertilization and development of eggs. Bites are painful but there is usually no pain after the fly stops feeding. The stable fly is a persistent feeder and will continue trying t...

Molecular Gene Profiling of Clostridium botulinum Group III and Its Detection in Naturally Contaminated Samples Originating from Various European Countries

PubMed Central

Woudstra, Cedric; Le Maréchal, Caroline; Souillard, Rozenn; Bayon-Auboyer, Marie-Hélène; Anniballi, Fabrizio; Auricchio, Bruna; De Medici, Dario; Bano, Luca; Koene, Miriam; Sansonetti, Marie-Hélène; Desoutter, Denise; Hansbauer, Eva-Maria; Dorner, Martin B.; Dorner, Brigitte G.

2015-01-01

We report the development of real-time PCR assays for genotyping Clostridium botulinum group III targeting the newly defined C. novyi sensu lato group; the nontoxic nonhemagglutinin (NTNH)-encoding gene ntnh; the botulinum neurotoxin (BoNT)-encoding genes bont/C, bont/C/D, bont/D, and bont/D/C; and the flagellin (fliC) gene. The genetic diversity of fliC among C. botulinum group III strains resulted in the definition of five major subgroups named fliC-I to fliC-V. Investigation of fliC subtypes in 560 samples, with various European origins, showed that fliC-I was predominant and found exclusively in samples contaminated by C. botulinum type C/D, fliC-II was rarely detected, no sample was recorded as fliC-III or fliC-V, and only C. botulinum type D/C samples tested positive for fliC-IV. The lack of genetic diversity of the flagellin gene of C. botulinum type C/D would support a clonal spread of type C/D strains in different geographical areas. fliC-I to fliC-III are genetically related (87% to 92% sequence identity), whereas fliC-IV from C. botulinum type D/C is more genetically distant from the other fliC types (with only 50% sequence identity). These findings suggest fliC-I to fliC-III have evolved in a common environment and support a different genetic evolution for fliC-IV. A combination of the C. novyi sensu lato, ntnh, bont, and fliC PCR assays developed in this study allowed better characterization of C. botulinum group III and showed the group to be less genetically diverse than C. botulinum groups I and II, supporting a slow genetic evolution of the strains belonging to C. botulinum group III. PMID:25636839

European Scientific Notes. Volume 36, Number 2,

DTIC Science & Technology

1982-02-28

colleagues at creases in process complexity and cost of the the University College of Swansea have con- product . So far, aluminum alloy, steel, and...associated with metal spray processing can stream of metal impinging on a disk rotating at impart to the solidified product . 3,000 to 5,000 rpm is...the point. Indeed, the pilot can simplicity, economy , stand-alone operability, often "fly the point" as the approach continues, portability, and

McDonnell Douglas Space Systems worker checks STS-46 TSS wiring at KSC O and C

NASA Technical Reports Server (NTRS)

1991-01-01

In the Kennedy Space Center (KSC) Operations and Checkout (O and C) Building, a McDonnell Douglas Space Systems technician Hugh Beins, wearing a clean suit, inspects a complex array of wiring for the Tethered Satellite System (TSS) scheduled to fly on STS-46 aboard Atlantis, Orbiter Vehicle (OV) 104. Other technicians work on the spacelab enhanced multiplexer/demultiplexer pallet (EMP) and support struts in the background.

Tolerance of house fly, Musca domestica L. (Diptera: Muscidae) to dichlorvos (76% EC) an insecticide used for fly control in the tsunami-hit coastal villages of southern India.

PubMed

Srinivasan, R; Jambulingam, P; Gunasekaran, K; Boopathidoss, P S

2008-02-01

The Directorate of Public Health (DPH), Tamil Nadu, in southern India employed spraying of dichlorvos (76% EC) for quick elimination of fly concentrations in the tsunami-hit coastal villages at the concentration of 304g (a.i.)/10,000m(2). However, nuisance of house flies remained high particularly in temporary shelters and centralized relief kitchens. Susceptibility of house fly, Musca domestica to dichlorvos was determined in the laboratory to provide information for an effective management of this pest. Various concentrations of dichlorvos (76% EC) viz., 0.1, 0.2, 0.4, 0.6 and 0.8microg (a.i.) per fly, were tested using topical application against F(1) progenies of house flies collected 12 months after insecticide applications from different habitats in the tsunami-hit coastal villages. Fly mortality was recorded at 24h post treatment. Parallel controls were maintained for comparison. Mortality of the house flies varied between 17.5% and 100% and increased with an increase in dosage of the insecticide. Mortality was >80% at 0.6 and 0.8microg (a.i.) per fly. The LD(50) of dichlorvos tested against flies collected from different villages varied from 0.218microg (a.i.) to 0.235microg (a.i.) per fly and the LD(90) varied from 0.574microg (a.i.) to 0.639microg (a.i.) per fly. House flies collected from a rural village, Thirukanur that had never been exposed for insecticide treatment in the past one decade, when tested, the mortality varied between 92.5% and 100% and increased with concentration of dichlorvos. Mortality was >90% from 0.2microg (a.i.) per fly and the LD(50) was 0.0399microg (a.i.)/fly, while the LD(90) was 0.1604microg (a.i.)/fly. The LD(90) values of the flies collected from the tsunami-hit villages were 3.5-3.9 times higher than that of the flies collected from Thirukanur. Fly abundance remained high in tsunami-hit villages with no marked reduction, suggesting that the flies had developed tolerance to dichlorvos. It is suggested that for an effective management of these resistant populations changing insecticides, application of unrelated insecticide, together with an appropriate environmental sanitation measure is necessary to keep the population under check.

A set of alkali and alkaline-earth coordination polymers based on the ligand 2-(1H-benzotriazol-1-yl) acetic acid: Effects the radius of metal ions on structures and properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Jin-Hua; Tang, Gui-Mei, E-mail: meiguit@163.com; Qin, Ting-Xiao

2014-11-15

Four new metal coordination complexes, namely, [Na(BTA)]{sub n} (1), [K{sub 2}(BTA){sub 2}(μ{sub 2}-H{sub 2}O)]{sub n} (2), and [M(BTA){sub 2}(H{sub 2}O){sub 2}]{sub n} (M=Ca(II) and Sr(II) for 3 and 4, respectively) [BTA=2-(1H-benzotriazol-1-yl) acetic anion], have been obtained under hydrothermal condition, by reacting the different alkali and alkaline-earth metal hydroxides with HBTA. Complexes 1–4 were structurally characterized by X-ray single-crystal diffraction, EA, IR, PXRD, and thermogravimetry analysis (TGA). These complexes display low-dimensional features displaying various two-dimensional (2D) and one-dimensional (1D) coordination motifs. Complex 1 displays a 2D layer with the thickness of 1.5 nm and possesses a topologic structure of a 11more » nodal net with Schläfli symbol of (3{sup 18}). Complex 2 also shows a thick 2D sheet and its topologic structure is a 9 nodes with Schläfli symbol of (3{sup 11}×4{sup 2}). Complexes 3 and 4 possess a 1D linear chain and further stack via hydrogen bonding interactions to generate a three-dimensional supramolecular architecture. These results suggest that both the coordination preferences of the metal ions and the versatile nature of this flexible ligand play a critical role in the final structures. The luminescent spectra show strong emission intensities in complexes 1–4, which display violet photoluminescence. Additionally, ferroelectric, dielectric and nonlinear optic (NLO) second-harmonic generation (SHG) properties of 2 are discussed in detail. - Graphical abstract: A set of alkali and alkaline-earth metal coordination polymers were hydrothermally synthesized by 2-(1H-benzotriazol-1-yl)acetic acid, displaying interesting topologic motifs from two-dimension to one-dimension and specific physical properties. - Highlights: • Alkali and alkaline-earth metal coordination polymers have been obtained. • The ligand 2-(1H-benzotriazol-1-yl)acetic acid has been adopted. • The two-dimensional and one-dimensional structures have been observed. • The properties of second harmonic generation and ferroelectricity for complex 2.« less

The High Teperature Influence on Geopolymer Fly Ash Mixture’s Compressisive Strength with Insudtrial Waste Material Substitution

NASA Astrophysics Data System (ADS)

Bayuaji, R.; Wibowo, B.; Subekti, S.; Santoso, S. E.; Hardiyanto, E.; Kaelani, Y.; Mallu, L. L.

2017-11-01

This research aimed to figure out the influence of fly ash mixture from the industrial waste at the temperatures of 150°C, 450°C, 750°C viewed from the strength and resistance of geopolymer paste. As a result, cement will be substituted by industrial waste like fly ash. This experimental research was conducted on the mix design of geopolymer concrete which was made by dimension with 2.5 cm in diameter and 5 cm in height from four mixture composition of fly ash and industrial waste i.e. 100% fly ash, 50% fly ash+50% bottom ash, 50% fly ash+50% sandblast, and 50% fly ash+50% carbide waste. Each mixture was tested in terms of porosity and compressive strength. In conclusion, in the mixture of 50% fly ash+50% Sandblast and 50% fly ash+50% bottom ash in 12 molars, 1.5 activator comparison can be used to substitute fly ash at high temperature. Meanwhile, the mixture of 50% fly ash+50% carbide waste in 8 molars, 0.5 activator comparison has very small strength remaining if it is compared to the mixture of fly ash and other industrial waste (Bottom ash and Sandblast). The performance of mixture paste of 50% fly ash+50% carbide waste was very vulnerable after being burnt. Consequently, it cannot be used as the main structure at high temperature.

Evaluation of commercial and field-expedient baited traps for house flies, Musca domestica L. (Diptera: Muscidae).

USDA-ARS?s Scientific Manuscript database

A comparison of 9 commercial baited fly traps on Florida dairy farms demonstrated that Terminator traps collected significantly more (13,323/trap) house flies (Musca domestica L.) than the others tested; Final Flight, Fly Magnet and FliesBeGone traps collected intermediate numbers of flies (834-2,16...

An annotated checklist of the horse flies, deer flies, and yellow flies (Diptera: Tabanidae) of Florida

USDA-ARS?s Scientific Manuscript database

The family Tabanidae includes the horse flies, deer flies, and yellow flies and is considered a significant pest of livestock throughout the United States, including Florida. Tabanids can easily become a major pest of man, especially salt marsh species which are known to readily feed on humans and o...

76 FR 26654 - Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-09

... Fly or South American Fruit Fly Exist AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION... Mediterranean fruit fly quarantined areas in the United States with a certificate if the fruit is safeguarded... regulations to remove trapping requirements for Mediterranean fruit fly for Hass avocados imported from the...

76 FR 18419 - Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-04

... Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist AGENCY: Animal and... Mediterranean fruit fly quarantined areas in the United States with a certificate if the fruit is safeguarded... quarantine regulations to remove trapping requirements for Mediterranean fruit fly for Hass avocados imported...

Chemical composition and physical properties of filter fly ashes from eight grate-fired biomass combustion plants.

PubMed

Lanzerstorfer, Christof

2015-04-01

For the handling, treatment and utilization of fly ash from biomass combustion its chemical composition and physical properties are important. In this study eight filter fly ashes from different grate-fired biomass combustion plants were investigated. In fly ash from straw combustion high concentrations of (K) were found, whereas in the fly ash from wood combustion the concentrations of Ca and Mg were higher. The average concentration of PO4(3-) was similar in both types of fly ashes. In all wood fly ashes some measured heavy metal concentrations were above the limits for utilization. The straw fly ashes were much less contaminated and can be utilized. For wood fly ash most parameters showed little variation, except from one fly ash where the dust pre-separator is in poor condition. The average values were: mass median diameter 4.3±0.8 μm, spread of particle size distribution 19±11, particle density 2620±80 kg/m3 and angle of repose 50°±1°. The density of the straw fly ashes is lower (2260±80 kg/m3) and the spread of the size distribution is higher (72±24). For one straw combustion fly ash the values of the mass median diameter and the angle of repose were similar to the values of wood combustion fly ash, for the other straw fly ash the values differed considerably. While the particle size of this fly ash was much smaller, surprisingly the angle of repose was also lower. This can be attributed to the formation of small agglomerates in this fly ash, which were not disintegrated without a certain stress. Copyright © 2015. Published by Elsevier B.V.

Susceptibility of black soldier fly (Diptera: Stratiomyidae) larvae and adults to four insecticides.

PubMed

Tomberlin, Jeffery K; Sheppard, D Craig; Joyce, John A

2002-06-01

Dosage-mortality regressions were determined for black soldier fly, Hermetia illucens (L.), larvae fed cyromazine or pyriproxifen treated media. Cyromazine LC50 for larvae dying before becoming prepupae ranged from 0.25 to 0.28 ppm with dosage-mortality regression slopes between 5.79 and 12.04. Cyromazine LC50s for larvae dying before emergence ranged from 0.13 to 0.19 ppm with dosage-mortality regression slopes between 3.94 and 7.69. Pyriproxifen dosage-mortality regressions were not generated for larvae failing to become prepupae since <32% mortality was recorded at the highest concentration of 1,857 ppm. LC50s for larvae failing to become adults ranged from 0.10 to 0.12 ppm with dosage mortality-regression slopes between 1.67 and 2.32. Lambda-cyhalothrin and permethrin dosage-mortality regressions were determined for wild adult black soldier flies and house flies, Musca domestica L., and for susceptible house flies. Our results indicate that the wild house fly, unlike the black soldier fly, population was highly resistant to each of these pyrethroids. Regression slopes for black soldier flies exposed to lambda-cyhalothrin were twice as steep as those determined for the wild house fly strain. Accordingly, LC50s for the black soldier fly and susceptible house fly were 10- to 30-fold lower than those determined for wild house flies. The differential sensitivity between wild black soldier flies and house flies might be due to behavioral differences. Adult house flies usually remain in animal facilities with the possibility of every adult receiving pesticide exposure, while black soldier fly adults are typically present only during emergence and oviposition thereby limiting their exposure.

Proceedings from the 2nd International Symposium on Formation Flying Missions and Technologies

NASA Technical Reports Server (NTRS)

2004-01-01

Topics discussed include: The Stellar Imager (SI) "Vision Mission"; First Formation Flying Demonstration Mission Including on Flight Nulling; Formation Flying X-ray Telescope in L2 Orbit; SPECS: The Kilometer-baseline Far-IR Interferometer in NASA's Space Science Roadmap Presentation; A Tight Formation for Along-track SAR Interferometry; Realization of the Solar Power Satellite using the Formation Flying Solar Reflector; SIMBOL-X : Formation Flying for High-Energy Astrophysics; High Precision Optical Metrology for DARWIN; Close Formation Flight of Micro-Satellites for SAR Interferometry; Station-Keeping Requirements for Astronomical Imaging with Constellations of Free-Flying Collectors; Closed-Loop Control of Formation Flying Satellites; Formation Control for the MAXIM Mission; Precision Formation Keeping at L2 Using the Autonomous Formation Flying Sensor; Robust Control of Multiple Spacecraft Formation Flying; Virtual Rigid Body (VRB) Satellite Formation Control: Stable Mode-Switching and Cross-Coupling; Electromagnetic Formation Flight (EMFF) System Design, Mission Capabilities, and Testbed Development; Navigation Algorithms for Formation Flying Missions; Use of Formation Flying Small Satellites Incorporating OISL's in a Tandem Cluster Mission; Semimajor Axis Estimation Strategies; Relative Attitude Determination of Earth Orbiting Formations Using GPS Receivers; Analysis of Formation Flying in Eccentric Orbits Using Linearized Equations of Relative Motion; Conservative Analytical Collision Probabilities for Orbital Formation Flying; Equations of Motion and Stability of Two Spacecraft in Formation at the Earth/Moon Triangular Libration Points; Formations Near the Libration Points: Design Strategies Using Natural and Non-Natural Ares; An Overview of the Formation and Attitude Control System for the Terrestrial Planet Finder Formation Flying Interferometer; GVE-Based Dynamics and Control for Formation Flying Spacecraft; GNC System Design for a New Concept of X-Ray Distributed Telescope; GNC System for the Deployment and Fine Control of the DARWIN Free-Flying Interferometer; Formation Algorithm and Simulation Testbed; and PLATFORM: A Formation Flying, RvD and Robotic Validation Test-bench.

Analysis of augmented aircraft flying qualities through application of the Neal-Smith criterion

NASA Technical Reports Server (NTRS)

Bailey, R. E.; Smith, R. E.

1981-01-01

The Neal-Smith criterion is examined for possible applications in the evaluation of augmented fighter aircraft flying qualities. Longitudinal and lateral flying qualities are addressed. Based on the application of several longitudinal flying qualities data bases, revisions are proposed to the original criterion. Examples are given which show the revised criterion to be a good discriminator of pitch flying qualities. Initial results of lateral flying qualities evaluation through application of the Neal-Smith criterion are poor. Lateral aircraft configurations whose flying qualities are degraded by roll ratcheting effects map into the Level 1 region of the criterion. A third dimension of the criterion for flying qualities specification is evident. Additional criteria are proposed to incorporate this dimension into the criterion structure for flying qualities analysis.

Flightless I interacts with NMMIIA to promote cell extension formation, which enables collagen remodeling

PubMed Central

Arora, Pamma D.; Wang, Yongqiang; Bresnick, Anne; Janmey, Paul A.; McCulloch, Christopher A.

2015-01-01

We examined the role of the actin-capping protein flightless I (FliI) in collagen remodeling by mouse fibroblasts. FliI-overexpressing cells exhibited reduced spreading on collagen but formed elongated protrusions that stained for myosin10 and fascin and penetrated pores of collagen-coated membranes. Inhibition of Cdc42 blocked formation of cell protrusions. In FliI-knockdown cells, transfection with constitutively active Cdc42 did not enable protrusion formation. FliI-overexpressing cells displayed increased uptake and degradation of exogenous collagen and strongly compacted collagen fibrils, which was blocked by blebbistatin. Mass spectrometry analysis of FliI immunoprecipitates showed that FliI associated with nonmuscle myosin IIA (NMMIIA), which was confirmed by immunoprecipitation. GFP-FliI colocalized with NMMIIA at cell protrusions. Purified FliI containing gelsolin-like domains (GLDs) 1–6 capped actin filaments efficiently, whereas FliI GLD 2–6 did not. Binding assays showed strong interaction of purified FliI protein (GLD 1–6) with the rod domain of NMMIIA (kD = 0.146 μM), whereas FliI GLD 2–6 showed lower binding affinity (kD = 0.8584 μM). Cells expressing FliI GLD 2–6 exhibited fewer cell extensions, did not colocalize with NMMIIA, and showed reduced collagen uptake compared with cells expressing FliI GLD 1–6. We conclude that FliI interacts with NMMIIA to promote cell extension formation, which enables collagen remodeling in fibroblasts. PMID:25877872

Releases of Psyttalia fletcheri (Hymenoptera: Braconidae) and sterile flies to suppress melon fly (Diptera: Tephritidae) in Hawaii.

PubMed

Vargas, Roger I; Long, Jay; Miller, Neil W; Delate, Kathleen; Jackson, Charles G; Uchida, Grant K; Bautista, Renato C; Harris, Ernie J

2004-10-01

Ivy gourd, Coccinia grandis (L.) Voigt, patches throughout Kailua-Kona, Hawaii Island, HI, were identified as persistent sources of melon fly, Bactrocera cucurbitae (Coquillett). These patches had a low incidence of Psyttalia fletcheri (Silvestri), its major braconid parasitoid natural enemy in Hawaii, and were used to evaluate augmentative releases of P. fletcheri against melon fly. In field cage studies of releases, numbers of melon flies emerging from ivy gourd fruit placed inside treatment cages were reduced up to 21-fold, and numbers of parasitoids were increased 11-fold. In open field releases of P. fletcheri into ivy gourd patches, parasitization rates were increased 4.7 times in release plots compared with those in control plots. However, there was no significant reduction in emergence of melon flies from fruit. In subsequent cage tests with sterile melon flies and P. fletcheri, combinations of sterile flies and P. fletcheri produced the greatest reduction (9-fold) in melon fly emergence from zucchini, Cucurbita pepo L. Reductions obtained with sterile flies alone or in combination with parasitoids were significantly greater than those in the control, whereas those for parasitoids alone were not. Although these results suggest that the effects of sterile flies were greater than those for parasitoids, from a multitactic melon fly management strategy, sterile flies would complement the effects of P. fletcheri. Cost and sustainability of these nonchemical approaches will be examined further in an ongoing areawide pest management program for melon fly in Hawaii.

Molecular detection of canine parvovirus in flies (Diptera) at open and closed canine facilities in the eastern United States.

PubMed

Bagshaw, Clarence; Isdell, Allen E; Thiruvaiyaru, Dharma S; Brisbin, I Lehr; Sanchez, Susan

2014-06-01

More than thirty years have passed since canine parvovirus (CPV) emerged as a significant pathogen and it continues to pose a severe threat to world canine populations. Published information suggests that flies (Diptera) may play a role in spreading this virus; however, they have not been studied extensively and the degree of their involvement is not known. This investigation was directed toward evaluating the vector capacity of such flies and determining their potential role in the transmission and ecology of CPV. Molecular diagnostic methods were used in this cross-sectional study to detect the presence of CPV in flies trapped at thirty-eight canine facilities. The flies involved were identified as belonging to the house fly (Mucidae), flesh fly (Sarcophagidae) and blow/bottle fly (Calliphoridae) families. A primary surveillance location (PSL) was established at a canine facility in south-central South Carolina, USA, to identify fly-virus interaction within the canine facility environment. Flies trapped at this location were pooled monthly and assayed for CPV using polymerase chain reaction (PCR) methods. These insects were found to be positive for CPV every month from February through the end of November 2011. Fly vector behavior and seasonality were documented and potential environmental risk factors were evaluated. Statistical analyses were conducted to compare the mean numbers of each of the three fly families captured, and after determining fly CPV status (positive or negative), it was determined whether there were significant relationships between numbers of flies captured, seasonal numbers of CPV cases, temperature and rainfall. Flies were also sampled at thirty-seven additional canine facility surveillance locations (ASL) and at four non-canine animal industry locations serving as negative field controls. Canine facility risk factors were identified and evaluated. Statistical analyses were conducted on the number of CPV cases reported within the past year to determine the correlation of fly CPV status (positive or negative) for each facility, facility design (open or closed), mean number of dogs present monthly and number of flies captured. Significant differences occurred between fly CPV positive vs. negative sites with regard to their CPV case numbers, fly numbers captured, and number of dogs present. At the ASL, a statistically significant relationship was found between PCR-determined fly CPV status (positive or negative) and facility design (open vs. closed). Open-facility designs were likely to have more CPV outbreaks and more likely to have flies testing positive for CPV DNA. Copyright © 2014 Elsevier B.V. All rights reserved.

Hanuman Complex And its Resolution : An Illustration of Psychotherapy from Indian mythology

PubMed Central

Wig, N N

2004-01-01

The rich heritage of Indian mythology has been very little explored and used in psychotherapy in India. The present article deals with the story of Hanuman. How he lost the knowledge about his power to fly due to a childhood curse by Rishis and how he regained his powers when reminded by Jambavan during a crucial mission in search of Queen Sita, is the subject of author′s description of Hanuman complex and its resolution. The author has often used this story in helping patients in psychotherapy as well as in teaching medical doctors and trainees in psychiatry. A plea is made for wider use of stories from Indian mythology in psychiatric practice. PMID:21206772

Dynamic Emulation of NASA Missions for IVandV: A Case Study of JWST and SLS

NASA Technical Reports Server (NTRS)

Yokum, Steve

2015-01-01

Software-Only-Simulations are an emerging but quickly developing field of study throughout NASA. The NASA Independent Verification Validation (IVV) Independent Test Capability (ITC) team has been rapidly building a collection of simulators for a wide range of NASA missions. ITC specializes in full end-to-end simulations that enable developers, VV personnel, and operators to test-as-you-fly. In four years, the team has delivered a wide variety of spacecraft simulations ranging from low complexity science missions such as the Global Precipitation Management (GPM) satellite and the Deep Space Climate Observatory (DSCOVR), to the extremely complex missions such as the James Webb Space Telescope (JWST) and Space Launch System (SLS).

Biomechanics and biomimetics in insect-inspired flight systems.

PubMed

Liu, Hao; Ravi, Sridhar; Kolomenskiy, Dmitry; Tanaka, Hiroto

2016-09-26

Insect- and bird-size drones-micro air vehicles (MAV) that can perform autonomous flight in natural and man-made environments are now an active and well-integrated research area. MAVs normally operate at a low speed in a Reynolds number regime of 10(4)-10(5) or lower, in which most flying animals of insects, birds and bats fly, and encounter unconventional challenges in generating sufficient aerodynamic forces to stay airborne and in controlling flight autonomy to achieve complex manoeuvres. Flying insects that power and control flight by flapping wings are capable of sophisticated aerodynamic force production and precise, agile manoeuvring, through an integrated system consisting of wings to generate aerodynamic force, muscles to move the wings and a control system to modulate power output from the muscles. In this article, we give a selective review on the state of the art of biomechanics in bioinspired flight systems in terms of flapping and flexible wing aerodynamics, flight dynamics and stability, passive and active mechanisms in stabilization and control, as well as flapping flight in unsteady environments. We further highlight recent advances in biomimetics of flapping-wing MAVs with a specific focus on insect-inspired wing design and fabrication, as well as sensing systems.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. © 2016 The Author(s).

Timing matters: sonar call groups facilitate target localization in bats.

PubMed

Kothari, Ninad B; Wohlgemuth, Melville J; Hulgard, Katrine; Surlykke, Annemarie; Moss, Cynthia F

2014-01-01

To successfully negotiate a cluttered environment, an echolocating bat must control the timing of motor behaviors in response to dynamic sensory information. Here we detail the big brown bat's adaptive temporal control over sonar call production for tracking prey, moving predictably or unpredictably, under different experimental conditions. We studied the adaptive control of vocal-motor behaviors in free-flying big brown bats, Eptesicus fuscus, as they captured tethered and free-flying insects, in open and cluttered environments. We also studied adaptive sonar behavior in bats trained to track moving targets from a resting position. In each of these experiments, bats adjusted the features of their calls to separate target and clutter. Under many task conditions, flying bats produced prominent sonar sound groups identified as clusters of echolocation pulses with relatively stable intervals, surrounded by longer pulse intervals. In experiments where bats tracked approaching targets from a resting position, bats also produced sonar sound groups, and the prevalence of these sonar sound groups increased when motion of the target was unpredictable. We hypothesize that sonar sound groups produced during flight, and the sonar call doublets produced by a bat tracking a target from a resting position, help the animal resolve dynamic target location and represent the echo scene in greater detail. Collectively, our data reveal adaptive temporal control over sonar call production that allows the bat to negotiate a complex and dynamic environment.

Timing matters: sonar call groups facilitate target localization in bats

PubMed Central

Kothari, Ninad B.; Wohlgemuth, Melville J.; Hulgard, Katrine; Surlykke, Annemarie; Moss, Cynthia F.

2014-01-01

To successfully negotiate a cluttered environment, an echolocating bat must control the timing of motor behaviors in response to dynamic sensory information. Here we detail the big brown bat's adaptive temporal control over sonar call production for tracking prey, moving predictably or unpredictably, under different experimental conditions. We studied the adaptive control of vocal-motor behaviors in free-flying big brown bats, Eptesicus fuscus, as they captured tethered and free-flying insects, in open and cluttered environments. We also studied adaptive sonar behavior in bats trained to track moving targets from a resting position. In each of these experiments, bats adjusted the features of their calls to separate target and clutter. Under many task conditions, flying bats produced prominent sonar sound groups identified as clusters of echolocation pulses with relatively stable intervals, surrounded by longer pulse intervals. In experiments where bats tracked approaching targets from a resting position, bats also produced sonar sound groups, and the prevalence of these sonar sound groups increased when motion of the target was unpredictable. We hypothesize that sonar sound groups produced during flight, and the sonar call doublets produced by a bat tracking a target from a resting position, help the animal resolve dynamic target location and represent the echo scene in greater detail. Collectively, our data reveal adaptive temporal control over sonar call production that allows the bat to negotiate a complex and dynamic environment. PMID:24860509

Animal Feces Contribute to Domestic Fecal Contamination: Evidence from E. coli Measured in Water, Hands, Food, Flies, and Soil in Bangladesh.

PubMed

Ercumen, Ayse; Pickering, Amy J; Kwong, Laura H; Arnold, Benjamin F; Parvez, Sarker Masud; Alam, Mahfuja; Sen, Debashis; Islam, Sharmin; Kullmann, Craig; Chase, Claire; Ahmed, Rokeya; Unicomb, Leanne; Luby, Stephen P; Colford, John M

2017-08-01

Fecal-oral pathogens are transmitted through complex, environmentally mediated pathways. Sanitation interventions that isolate human feces from the environment may reduce transmission but have shown limited impact on environmental contamination. We conducted a study in rural Bangladesh to (1) quantify domestic fecal contamination in settings with high on-site sanitation coverage; (2) determine how domestic animals affect fecal contamination; and (3) assess how each environmental pathway affects others. We collected water, hand rinse, food, soil, and fly samples from 608 households. We analyzed samples with IDEXX Quantitray for the most probable number (MPN) of E. coli. We detected E. coli in source water (25%), stored water (77%), child hands (43%), food (58%), flies (50%), ponds (97%), and soil (95%). Soil had >120 000 mean MPN E. coli per gram. In compounds with vs without animals, E. coli was higher by 0.54 log 10 in soil, 0.40 log 10 in stored water and 0.61 log 10 in food (p < 0.05). E. coli in stored water and food increased with increasing E. coli in soil, ponds, source water and hands. We provide empirical evidence of fecal transmission in the domestic environment despite on-site sanitation. Animal feces contribute to fecal contamination, and fecal indicator bacteria do not strictly indicate human fecal contamination when animals are present.

Comparison study of phosphorus adsorption on different waste solids: Fly ash, red mud and ferric-alum water treatment residues.

PubMed

Wang, Ying; Yu, Yange; Li, Haiyan; Shen, Chanchan

2016-12-01

The adsorption of phosphorus (P) onto three industrial solid wastes (fly ash, red mud and ferric-alum water treatment residual (FAR)) and their modified materials was studied systematically via batch experiments. Compared with two natural adsorbents (zeolite and diatomite), three solid wastes possessed a higher adsorption capacity for P because of the higher Fe, Al and Ca contents. After modification (i.e., the fly ash and red mud modified by FeCl 3 and FARs modified by HCl), the adsorption capacity increased, especially for the modified red mud, where more Fe bonded P was observed. The P adsorption kinetics can be satisfactorily fitted using the pseudo-second-order model. The Langmuir model can describe well the P adsorption on all of the samples in our study. pH and dissolved organic matter (DOM) are two important factors for P adsorption. Under neutral conditions, the maximum adsorption amount on the modified materials was observed. With the deviation from pH7, the adsorption amount decreased, which resulted from the change of P species in water and surface charges of the adsorbents. The DOM in water can promote P adsorption, which may be due to the promotion effects of humic-Fe(Al) complexes and the pH buffer function exceeds the depression of competitive adsorption. Copyright © 2016. Published by Elsevier B.V.

Expanding the view of Clock and cycle gene evolution in Diptera.

PubMed

Chahad-Ehlers, S; Arthur, L P; Lima, A L A; Gesto, J S M; Torres, F R; Peixoto, A A; de Brito, R A

2017-06-01

We expanded the view of Clock (Clk) and cycle (cyc) gene evolution in Diptera by studying the fruit fly Anastrepha fraterculus (Afra), a Brachycera. Despite the high conservation of clock genes amongst insect groups, striking structural and functional differences of some clocks have appeared throughout evolution. Clk and cyc nucleotide sequences and corresponding proteins were characterized, along with their mRNA expression data, to provide an evolutionary overview in the two major groups of Diptera: Lower Diptera and Higher Brachycera. We found that AfraCYC lacks the BMAL (Brain and muscle ARNT-like) C-terminus region (BCTR) domain and is constitutively expressed, suggesting that AfraCLK has the main transactivation function, which is corroborated by the presence of poly-Q repeats and an oscillatory pattern. Our analysis suggests that the loss of BCTR in CYC is not exclusive of drosophilids, as it also occurs in other Acalyptratae flies such as tephritids and drosophilids, however, but it is also present in some Calyptratae, such as Muscidae, Calliphoridae and Sarcophagidae. This indicates that BCTR is missing from CYC of all higher-level Brachycera and that it was lost during the evolution of Lower Brachycera. Thus, we can infer that CLK protein may play the main role in the CLK\\CYC transcription complex in these flies, like in its Drosophila orthologues. © 2017 The Royal Entomological Society.

Animal Feces Contribute to Domestic Fecal Contamination: Evidence from E. coli Measured in Water, Hands, Food, Flies, and Soil in Bangladesh

PubMed Central

2017-01-01

Fecal-oral pathogens are transmitted through complex, environmentally mediated pathways. Sanitation interventions that isolate human feces from the environment may reduce transmission but have shown limited impact on environmental contamination. We conducted a study in rural Bangladesh to (1) quantify domestic fecal contamination in settings with high on-site sanitation coverage; (2) determine how domestic animals affect fecal contamination; and (3) assess how each environmental pathway affects others. We collected water, hand rinse, food, soil, and fly samples from 608 households. We analyzed samples with IDEXX Quantitray for the most probable number (MPN) of E. coli. We detected E. coli in source water (25%), stored water (77%), child hands (43%), food (58%), flies (50%), ponds (97%), and soil (95%). Soil had >120 000 mean MPN E. coli per gram. In compounds with vs without animals, E. coli was higher by 0.54 log10 in soil, 0.40 log10 in stored water and 0.61 log10 in food (p < 0.05). E. coli in stored water and food increased with increasing E. coli in soil, ponds, source water and hands. We provide empirical evidence of fecal transmission in the domestic environment despite on-site sanitation. Animal feces contribute to fecal contamination, and fecal indicator bacteria do not strictly indicate human fecal contamination when animals are present. PMID:28686435

IsoPlot: a database for comparison of mRNA isoforms in fruit fly and mosquitoes

PubMed Central

Ng, I-Man; Tsai, Shang-Chi

2017-01-01

Abstract Alternative splicing (AS), a mechanism by which different forms of mature messenger RNAs (mRNAs) are generated from the same gene, widely occurs in the metazoan genomes. Knowledge about isoform variants and abundance is crucial for understanding the functional context in the molecular diversity of the species. With increasing transcriptome data of model and non-model species, a database for visualization and comparison of AS events with up-to-date information is needed for further research. IsoPlot is a publicly available database with visualization tools for exploration of AS events, including three major species of mosquitoes, Aedes aegypti, Anopheles gambiae, and Culex quinquefasciatus, and fruit fly Drosophila melanogaster, the model insect species. IsoPlot includes not only 88,663 annotated transcripts but also 17,037 newly predicted transcripts from massive transcriptome data at different developmental stages of mosquitoes. The web interface enables users to explore the patterns and abundance of isoforms in different experimental conditions as well as cross-species sequence comparison of orthologous transcripts. IsoPlot provides a platform for researchers to access comprehensive information about AS events in mosquitoes and fruit fly. Our database is available on the web via an interactive user interface with an intuitive graphical design, which is applicable for the comparison of complex isoforms within or between species. Database URL: http://isoplot.iis.sinica.edu.tw/ PMID:29220459

Selective endosomal microautophagy is starvation-inducible in Drosophila.

PubMed

Mukherjee, Anindita; Patel, Bindi; Koga, Hiroshi; Cuervo, Ana Maria; Jenny, Andreas

2016-11-01

Autophagy delivers cytosolic components to lysosomes for degradation and is thus essential for cellular homeostasis and to cope with different stressors. As such, autophagy counteracts various human diseases and its reduction leads to aging-like phenotypes. Macroautophagy (MA) can selectively degrade organelles or aggregated proteins, whereas selective degradation of single proteins has only been described for chaperone-mediated autophagy (CMA) and endosomal microautophagy (eMI). These 2 autophagic pathways are specific for proteins containing KFERQ-related targeting motifs. Using a KFERQ-tagged fluorescent biosensor, we have identified an eMI-like pathway in Drosophila melanogaster. We show that this biosensor localizes to late endosomes and lysosomes upon prolonged starvation in a KFERQ- and Hsc70-4- dependent manner. Furthermore, fly eMI requires endosomal multivesicular body formation mediated by ESCRT complex components. Importantly, induction of Drosophila eMI requires longer starvation than the induction of MA and is independent of the critical MA genes atg5, atg7, and atg12. Furthermore, inhibition of Tor signaling induces eMI in flies under nutrient rich conditions, and, as eMI in Drosophila also requires atg1 and atg13, our data suggest that these genes may have a novel, additional role in regulating eMI in flies. Overall, our data provide the first evidence for a novel, starvation-inducible, catabolic process resembling endosomal microautophagy in the Drosophila fat body.

Neural network modeling of the kinetics of SO2 removal by fly ash-based sorbent.

PubMed

Raymond-Ooi, E H; Lee, K T; Mohamed, A R; Chu, K H

2006-01-01

The mechanistic modeling of the sulfation reaction between fly ash-based sorbent and SO2 is a challenging task due to a variety reasons including the complexity of the reaction itself and the inability to measure some of the key parameters of the reaction. In this work, the possibility of modeling the sulfation reaction kinetics using a purely data-driven neural network was investigated. Experiments on SO2 removal by a sorbent prepared from coal fly ash/CaO/CaSO4 were conducted using a fixed bed reactor to generate a database to train and validate the neural network model. Extensive SO2 removal data points were obtained by varying three process variables, namely, SO2 inlet concentration (500-2000 mg/L), reaction temperature (60-80 degreesC), and relative humidity (50-70%), as a function of reaction time (0-60 min). Modeling results show that the neural network can provide excellent fits to the SO2 removal data after considerable training and can be successfully used to predict the extent of SO2 removal as a function of time even when the process variables are outside the training domain. From a modeling standpoint, the suitably trained and validated neural network with excellent interpolation and extrapolation properties could have immediate practical benefits in the absence of a theoretical model.

Evaluation of Pollutant Leaching Potential of Coal Ashes for Recycling

NASA Astrophysics Data System (ADS)

Park, D.; Woo, N. C.; Kim, H.; Yoon, H.; Chung, D.

2011-12-01

By 2009, coal ashes produced from coal-based power plants in Korea have been reused as cement supplement materials; however, the rest is mostly disposed in landfills inside the plant properties. Continuous production of coal ashes and limited landfill sites require more recycles of coal ashes as base materials, specifically in constructions of roads and of huge industrial complex. Previous researches showed that coal ashes could contain various metals such as arsenic(As), chromium(Cr), lead(Pb), nickel(Ni), selenium(Se), etc. In this study, we collected four types of bottom ashes and two of fly ashes from four coal-based power plants. These ash samples were tested with distilled water through the column leaching process in oxidized conditions. The column test results were compared with those of total digestion, sequential extraction processes and TCLP. Concentrations of metals in outflows from columns are generally greater in fly ashes than in bottom ashes, specifically for As, Se, B, Sr and SO4. Only one fly ash (J2-F) shows high concentrations of arsenic and selenium in leachate. Sequential extraction results indicate that these metals are in readily soluble forms, such as adsorbed, carbonated, and reducible forms. Results of TCLP analysis indicate no potential contaminants leached from the ashes. In conclusion, recycling of coal combustion ashes could be encouraged with proper tests such as sequential and leaching experiments.

Drosophila Cuticular Hydrocarbons Revisited: Mating Status Alters Cuticular Profiles

PubMed Central

Cobb, Matthew; Ferveur, Jean-François

2010-01-01

Most living organisms use pheromones for inter-individual communication. In Drosophila melanogaster flies, several pheromones perceived either by contact/at a short distance (cuticular hydrocarbons, CHs), or at a longer distance (cis-vaccenyl acetate, cVA), affect courtship and mating behaviours. However, it has not previously been possible to precisely identify all potential pheromonal compounds and simultaneously monitor their variation on a time scale. To overcome this limitation, we combined Solid Phase Micro-Extraction with gas-chromatography coupled with mass-spectrometry. This allowed us (i) to identify 59 cuticular compounds, including 17 new CHs; (ii) to precisely quantify the amount of each compound that could be detected by another fly, and (iii) to measure the variation of these substances as a function of aging and mating. Sex-specific variation appeared with age, while mating affected cuticular compounds in both sexes with three possible patterns: variation was (i) reciprocal in the two sexes, suggesting a passive mechanical transfer during mating, (ii) parallel in both sexes, such as for cVA which strikingly appeared during mating, or (iii) unilateral, presumably as a result of sexual interaction. We provide a complete reassessment of all Drosophila CHs and suggest that the chemical conversation between male and female flies is far more complex than is generally accepted. We conclude that focusing on individual compounds will not provide a satisfactory understanding of the evolution and function of chemical communication in Drosophila. PMID:20231905

Dynamics of the vortex wakes of flying and swimming vertebrates.

PubMed

Rayner, J M

1995-01-01

The vortex wakes of flying and swimming animals provide evidence of the history of aero- and hydrodynamic force generation during the locomotor cycle. Vortex-induced momentum flux in the wake is the reaction of forces the animal imposes on its environment, which must be in equilibrium with inertial and external forces. In flying birds and bats, the flapping wings generate lift both to provide thrust and to support the weight. Distinct wingbeat and wake movement patterns can be identified as gaits. In flow visualization experiments, only two wake patterns have been identified: a vortex ring gait with inactive upstroke, and a continuous vortex gait with active upstroke. These gaits may be modelled theoretically by free vortex and lifting line theory to predict mechanical energy consumption, aerodynamic forces and muscle activity. Longer-winged birds undergo a distinct gait change with speed, but shorter-winged species use the vortex ring gait at all speeds. In swimming fish, the situation is more complex: the wake vortices form a reversed von Kármán vortex street, but little is known about the mechanism of generation of the wake, or about how it varies with speed and acceleration or with body form and swimming mode. An unresolved complicating factor is the interaction between the drag wake of the flapping fish body and the thrusting wake from the tail.

Human myiasis in rural South Africa is under-reported.

PubMed

Kuria, Simon Kamande; Kingu, H J C; Villet, M H; Dhaffala, A

2015-01-08

Myiasis is the infestation of live tissue of humans and other vertebrates by larvae of flies. Worldwide, myiasis of humans is seldom reported, although the trend is gradually changing in some countries. Reports of human myiasis in Africa are few. Several cases of myiasis were recently seen at the Mthatha Hospital Complex, Mthatha, Eastern Cape Province, South Africa (SA). Because of a paucity of literature on myiasis from this region, surgeons and scientists from Walter Sisulu University, Mthatha, decided to document myiasis cases presenting either at Nelson Mandela Academic Hospital or Umtata General Hospital from May 2009 to April 2013. The objective was to determine the incidence, epidemiology, patient age group and gender, and fly species involved. The effect of season on incidence was also investigated. Twenty-five cases (14 men and 11 women) were recorded in the 4-year study period. The fly species involved were Lucilia sericata, L. cuprina, Chrysomya megacephala, C. chloropyga and Sarcophaga (Liosarcophaga) nodosa, the latter being confirmed as an agent for human myiasis for the first time. The patients were 3 - 78 years old (median 56). Cases were most numerous during spring and summer, and were associated with underlying pathologies typical of ageing. Myiasis is a more common medical condition than expected in the Mthatha region. The study shows that human myiasis is still frequently encountered in SA, and there is a need to understand its epidemiology better.

Loss of Drosophila i-AAA protease, dYME1L, causes abnormal mitochondria and apoptotic degeneration.

PubMed

Qi, Y; Liu, H; Daniels, M P; Zhang, G; Xu, H

2016-02-01

Mitochondrial AAA (ATPases Associated with diverse cellular Activities) proteases i-AAA (intermembrane space-AAA) and m-AAA (matrix-AAA) are closely related and have major roles in inner membrane protein homeostasis. Mutations of m-AAA proteases are associated with neuromuscular disorders in humans. However, the role of i-AAA in metazoans is poorly understood. We generated a deletion affecting Drosophila i-AAA, dYME1L (dYME1L(del)). Mutant flies exhibited premature aging, progressive locomotor deficiency and neurodegeneration that resemble some key features of m-AAA diseases. dYME1L(del) flies displayed elevated mitochondrial unfolded protein stress and irregular cristae. Aged dYME1L(del) flies had reduced complex I (NADH/ubiquinone oxidoreductase) activity, increased level of reactive oxygen species (ROS), severely disorganized mitochondrial membranes and increased apoptosis. Furthermore, inhibiting apoptosis by targeting dOmi (Drosophila Htra2/Omi) or DIAP1, or reducing ROS accumulation suppressed retinal degeneration. Our results suggest that i-AAA is essential for removing unfolded proteins and maintaining mitochondrial membrane architecture. Loss of i-AAA leads to the accumulation of oxidative damage and progressive deterioration of membrane integrity, which might contribute to apoptosis upon the release of proapoptotic molecules such as dOmi. Containing ROS level could be a potential strategy to manage mitochondrial AAA protease deficiency.

A Nutrient-Tunable Bistable Switch Controls Motility in Salmonella enterica Serovar Typhimurium

PubMed Central

Koirala, Santosh; Mears, Patrick; Sim, Martin; Golding, Ido; Chemla, Yann R.; Aldridge, Phillip D.

2014-01-01

ABSTRACT Many bacteria are motile only when nutrients are scarce. In contrast, Salmonella enterica serovar Typhimurium is motile only when nutrients are plentiful, suggesting that this bacterium uses motility for purposes other than foraging, most likely for host colonization. In this study, we investigated how nutrients affect motility in S. enterica and found that they tune the fraction of motile cells. In particular, we observed coexisting populations of motile and nonmotile cells, with the distribution being determined by the concentration of nutrients in the growth medium. Interestingly, S. enterica responds not to a single nutrient but apparently to a complex mixture of them. Using a combination of experimentation and mathematical modeling, we investigated the mechanism governing this behavior and found that it results from two antagonizing regulatory proteins, FliZ and YdiV. We also found that a positive feedback loop involving the alternate sigma factor FliA is required, although its role appears solely to amplify FliZ expression. We further demonstrate that the response is bistable: that is, genetically identical cells can exhibit different phenotypes under identical growth conditions. Together, these results uncover a new facet of the regulation of the flagellar genes in S. enterica and further demonstrate how bacteria employ phenotypic diversity as a general mechanism for adapting to change in their environment. PMID:25161191

Functional and evolutionary trade-offs co-occur between two consolidated memory phases in Drosophila melanogaster

PubMed Central

Lagasse, Fabrice; Moreno, Celine; Preat, Thomas; Mery, Frederic

2012-01-01

Memory is a complex and dynamic process that is composed of different phases. Its evolution under natural selection probably depends on a balance between fitness benefits and costs. In Drosophila, two separate forms of consolidated memory phases can be generated experimentally: anaesthesia-resistant memory (ARM) and long-term memory (LTM). In recent years, several studies have focused on the differences between these long-lasting memory types and have found that, at the functional level, ARM and LTM are antagonistic. How this functional relationship will affect their evolutionary dynamics remains unknown. We selected for flies with either improved ARM or improved LTM over several generations, and found that flies selected specifically for improvement of one consolidated memory phase show reduced performance in the other memory phase. We also found that improved LTM was linked to decreased longevity in male flies but not in females. Conversely, males with improved ARM had increased longevity. We found no correlation between either improved ARM or LTM and other phenotypic traits. This is, to our knowledge, the first evidence of a symmetrical evolutionary trade-off between two memory phases for the same learning task. Such trade-offs may have an important impact on the evolution of cognitive capacities. On a neural level, these results support the hypothesis that mechanisms underlying these forms of consolidated memory are, to some degree, antagonistic. PMID:22859595

Semiochemicals released from five bacteria identified from animal wounds infested by primary screwworms and their effects on fly behavioral activity.

PubMed

Zhu, Junwei J; Chaudhury, Muhammad F; Durso, Lisa M; Sagel, Agustin; Skoda, Steven R; Jelvez-Serra, Nadia S; Santanab, Euzebio Goulart

2017-01-01

The Primary screwworm, Cochliomyia hominivorax (Coquerel), is a serious pest feeding on living flesh of any warm-blooded animal, including humans. It was eradicated from the United States in the early 1980s using the sterile male technique. However, it was recently detected in populations of wild deer and pets in the Florida Keys of the US. For monitoring purposes, screwworm flies are normally trapped using attractant bait with liver. However, there has been little effort to develop an efficient monitoring system for detection of screwworm flies using a specific synthetic attractant blend. Several studies have shown that odors from animal wound fluids attract screwworm adults, particularly gravid females. Bacteria associated with animal wounds have been identified that act as a major source for this attraction. To understand what volatiles attract screwworms we inoculated bovine blood with previously identified bacteria. We identified volatile chemicals released from the inoculated blood and other selected media over time and assessed the effect of those chemicals on behavioral activity of adult screwworm flies. A total of 7 volatile compounds were collected from bacteria incubated in either broth or blood using solid-phase microextraction, and their chemical structures were identified by their characteristic mass spectrum fragments and confirmed by retention times in comparison to those of synthetic standards via gas chromatograph combined mass spectrometry analyses. Five major volatiles including dimethyl disulfide, dimethyl trisulfide, phenol, p-cresol and indole were detected from a mixture of 5 bacteria incubated in blood. The ratios of volatiles released differed among different incubation media, time and individual bacteria. A synthetic mixture containing the five compounds was demonstrated to be attractive to adult screwworm flies both in laboratory assays and field trapping trials. The results obtained from this study may assist in developing an efficient trapping system using the identified attractant blend to detect the infestation of primary screwworms. This is also the first study to explore the complex systems in volatile release profiles from 5 bacteria isolated from screwworm-infested animal wounds that are incubated with different media and incubation time, as well as individual and multi-species bacterial communities.

Pollination of Specklinia by nectar-feeding Drosophila: the first reported case of a deceptive syndrome employing aggregation pheromones in Orchidaceae

PubMed Central

Karremans, Adam P.; Pupulin, Franco; Grimaldi, David; Beentjes, Kevin K.; Butôt, Roland; Fazzi, Gregorio E.; Kaspers, Karsten; Kruizinga, Jaco; Roessingh, Peter; Smets, Erik F.; Gravendeel, Barbara

2015-01-01

Background and Aims The first documented observation of pollination in Pleurothallidinae was that of Endrés, who noticed that the ‘viscid sepals’ of Specklinia endotrachys were visited by a ‘small fly’. Chase would later identify the visiting flies as being members of the genus Drosophila. This study documents and describes how species of the S. endotrachys complex are pollinated by different Drosophila species. Methods Specimens of Specklinia and Drosophila were collected in the field in Costa Rica and preserved in the JBL and L herbaria. Flies were photographed, filmed and observed for several days during a 2-year period and were identified by a combination of non-invasive DNA barcoding and anatomical surveys. Tissue samples of the sepals, petals and labellum of Specklinia species were observed and documented by SEM, LM and TEM. Electroantennogram experiments were carried out on Drosophila hydei using the known aggregation pheromones ethyl tiglate, methyl tiglate and isopropyl tiglate. Floral compounds were analysed by gas chromatography–mass spectometry using those same pheromones as standards. Key Results Flowers of S. endotrachys, S. pfavii, S. remotiflora and S. spectabilis are visited and pollinated by several different but closely related Drosophila species. The flies are arrested by aggregation pheromones, including ethyl tiglate, methyl tiglate and isopropyl tiglate, released by the flowers, and to which at least D. hydei is very sensitive. Visible nectar drops on the adaxial surface of sepals are secreted by nectar-secreting stomata, encouraging male and female Drosophila to linger on the flowers for several hours at a time. The flies frequently show courtship behaviour, occasionally copulating. Several different Drosophila species can be found on a single Specklinia species. Conclusions Species of the S. endotrachys group share a similar pollination syndrome. There seem to be no species-specific relationships between the orchids and the flies. It is not expected that Specklinia species will hybridize naturally as their populations do not overlap geographically. The combination of pheromone attraction and nectar feeding is likely to be a generalized pollination syndrome in Pleurothallidinae. PMID:26071932

Prevalence and Relative Risk of Cronobacter spp., Salmonella spp., and Listeria monocytogenes Associated with the Body Surfaces and Guts of Individual Filth Flies

PubMed Central

Pearson, Rachel E. Goeriz; Miller, Amy K.; Ziobro, George C.

2012-01-01

Although flies are important vectors of food-borne pathogens, there is little information to accurately assess the food-related health risk of the presence of individual flies, especially in urban areas. This study quantifies the prevalence and the relative risk of food-borne pathogens associated with the body surfaces and guts of individual wild flies. One hundred flies were collected from the dumpsters of 10 randomly selected urban restaurants. Flies were identified using taxonomic keys before being individually dissected. Cronobacter spp., Salmonella spp., and Listeria monocytogenes were detected using the PCR-based BAX system Q7. Positive samples were confirmed by culture on specific media and through PCR amplification and sequencing or ribotyping. Among collected flies were the housefly, Musca domestica (47%), the blowflies, Lucilia cuprina (33%) and Lucilia sericata (14%), and others (6%). Cronobacter species were detected in 14% of flies, including C. sakazakii, C. turicensis, and C. universalis, leading to the proposal of flies as a natural reservoir of this food-borne pathogen. Six percent of flies carried Salmonella enterica, including the serovars Poona, Hadar, Schwarzengrund, Senftenberg, and Brackenridge. L. monocytogenes was detected in 3% of flies. Overall, the prevalence of food-borne pathogens was three times greater in the guts than on the body surfaces of the flies. The relative risk of flies carrying any of the three pathogens was associated with the type of pathogen, the body part of the fly, and the ambient temperature. These data enhance the ability to predict the microbiological risk associated with the presence of individual flies in food and food facilities. PMID:22941079

Dosage Compensation of the X Chromosome: A Complex Epigenetic Assignment Involving Chromatin Regulators and Long Noncoding RNAs.

PubMed

Samata, Maria; Akhtar, Asifa

2018-06-20

X chromosome regulation represents a prime example of an epigenetic phenomenon where coordinated regulation of a whole chromosome is required. In flies, this is achieved by transcriptional upregulation of X chromosomal genes in males to equalize the gene dosage differences in females. Chromatin-bound proteins and long noncoding RNAs (lncRNAs) constituting a ribonucleoprotein complex known as the male-specific lethal (MSL) complex or the dosage compensation complex mediate this process. MSL complex members decorate the male X chromosome, and their absence leads to male lethality. The male X chromosome is also enriched with histone H4 lysine 16 acetylation (H4K16ac), indicating that the chromatin compaction status of the X chromosome also plays an important role in transcriptional activation. How the X chromosome is specifically targeted and how dosage compensation is mechanistically achieved are central questions for the field. Here, we review recent advances, which reveal a complex interplay among lncRNAs, the chromatin landscape, transcription, and chromosome conformation that fine-tune X chromosome gene expression.

Tetrahedral silsesquioxane-C2H2Ti complex for hydrogen storage

NASA Astrophysics Data System (ADS)

Konda, Ravinder; Tavhare, Priyanka; Ingale, Nilesh; Chaudhari, Ajay

2018-04-01

The interaction of molecular hydrogen with tetrahedral silsesquioxane (T4)-C2H2Ti complex has been studied using Density Functional Theory with M06-2X functional and MP2 method with 6-311++G** basis set. T4-C2H2Ti complex can absorb maximum five hydrogen molecules with the gravimetric hydrogen storage capacity of 3.4 wt %. Adsorption energy calculations show that H2 adsorption on T4-C2H2Ti complex is favorable at room temperature by both the methods. We have studied the effect of temperature and pressure on Gibbs free energy corrected adsorption energies. Molecular dynamics simulations for H2 adsorbed T4-C2H2Ti complex have also been performed at 300K and show that loosely bonded H2 molecule flies away within 1fs. Various interaction energies within the complex are studied. Stability of a complex is predicted by means of a gap between Highest Occupied Molecular Orbital (HUMO) and Lowest Unoccupied Molecular Orbital (LUMO). The H2 desorption temperature for T4-C2H2Ti complex is calculated with Van't Hoff equation and it is found to be 229K.

Field trials of fatty acids and geraniol applied to cattle for suppression of horn flies, Haematobia irritans (Diptera: Muscidae), with observations on fly defensive behaviors.

PubMed

Mullens, Bradley A; Watson, D Wes; Gerry, Alec C; Sandelin, Broc A; Soto, Diane; Rawls, Diana; Denning, Steve; Guisewite, Lena; Cammack, Jonathan

2017-10-15

Adult horn fly populations were tracked on cattle for 2-week periods before, during and after multiple treatments (every 3-4days) with two repellents in a mineral oil carrier. Cattle were sprayed four times in a two-week period either with 2% geraniol (125ml/cow) or a 15% mixture of short chain fatty acids (C8-C9-C10)(250ml/cow), and there were untreated control cattle. Trials were conducted in California and North Carolina for 3 summers. Short-term fly counts (same day) on treated cattle were reduced by 61-99%, depending on material and trial, and the fatty acid mixture provided better control than geraniol. Horn fly counts were suppressed for 1-3 d and rebounded somewhat after both treatments. Consecutive treatments showed evidence of persistent impact in California where herds were more isolated. Rebounds to pre-treatment levels 3-4 d after treatment occurred more often in North Carolina, where other infested cattle were closer to treated herds. By 3-4 d post-treatment, horn flies were reduced by 29-61% in California and 0-83% in North Carolina, relative to pre-treatment. Background behavior frequencies were assessed from hundreds of counts on untreated, infested California cattle, where horn flies were the only abundant biting fly. Behavior averages were 16.5 tail flicks, 7.6 skin twitches, 1.2 head throws, or 0.2 leg stamps per 2min observation period. At horn fly densities from about 200 to more than 1000 flies per animal (moderate to high numbers), fly defensive behaviors on control cattle were poorly related (or unrelated) to fly numbers. Immediately after repellent application, however, flies were almost absent and behavior frequencies dropped distinctly. Cattle fly defensive behaviors therefore seem to be quite sensitive to low (less than 100 flies/animal) horn fly densities, and behaviors would be a poor quantitative tool to track fly stress at moderate densities and above. Both geraniol and the fatty acids show promise for horn fly control, especially in organic agriculture. Treatments at 1-2 d intervals probably would keep infestations below the economic threshold (200 flies/cow). Copyright © 2017 Elsevier B.V. All rights reserved.

78 FR 23786 - Settlement Conference

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-22

... convening a settlement conference between GameFly, Inc. and the Postal Service. This notice informs the.... GameFly Motion, Postal Service Reply, and GameFly Response IV. Analysis V. Settlement Procedures I..., 2013, GameFly, Inc. (GameFly) filed a motion requesting the Commission to establish standards and...

Functional Genomic Screening Reveals Splicing of the EWS-FLI1 Fusion Transcript as a Vulnerability in Ewing Sarcoma.

PubMed

Grohar, Patrick J; Kim, Suntae; Rangel Rivera, Guillermo O; Sen, Nirmalya; Haddock, Sara; Harlow, Matt L; Maloney, Nichole K; Zhu, Jack; O'Neill, Maura; Jones, Tamara L; Huppi, Konrad; Grandin, Magdalena; Gehlhaus, Kristen; Klumpp-Thomas, Carleen A; Buehler, Eugen; Helman, Lee J; Martin, Scott E; Caplen, Natasha J

2016-01-26

Ewing sarcoma cells depend on the EWS-FLI1 fusion transcription factor for cell survival. Using an assay of EWS-FLI1 activity and genome-wide RNAi screening, we have identified proteins required for the processing of the EWS-FLI1 pre-mRNA. We show that Ewing sarcoma cells harboring a genomic breakpoint that retains exon 8 of EWSR1 require the RNA-binding protein HNRNPH1 to express in-frame EWS-FLI1. We also demonstrate the sensitivity of EWS-FLI1 fusion transcripts to the loss of function of the U2 snRNP component, SF3B1. Disrupted splicing of the EWS-FLI1 transcript alters EWS-FLI1 protein expression and EWS-FLI1-driven expression. Our results show that the processing of the EWS-FLI1 fusion RNA is a potentially targetable vulnerability in Ewing sarcoma cells. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Evaluating Perceived Probability of Threat-Relevant Outcomes and Temporal Orientation in Flying Phobia.

PubMed

Mavromoustakos, Elena; Clark, Gavin I; Rock, Adam J

2016-01-01

Probability bias regarding threat-relevant outcomes has been demonstrated across anxiety disorders but has not been investigated in flying phobia. Individual temporal orientation (time perspective) may be hypothesised to influence estimates of negative outcomes occurring. The present study investigated whether probability bias could be demonstrated in flying phobia and whether probability estimates of negative flying events was predicted by time perspective. Sixty flying phobic and fifty-five non-flying-phobic adults were recruited to complete an online questionnaire. Participants completed the Flight Anxiety Scale, Probability Scale (measuring perceived probability of flying-negative events, general-negative and general positive events) and the Past-Negative, Future and Present-Hedonistic subscales of the Zimbardo Time Perspective Inventory (variables argued to predict mental travel forward and backward in time). The flying phobic group estimated the probability of flying negative and general negative events occurring as significantly higher than non-flying phobics. Past-Negative scores (positively) and Present-Hedonistic scores (negatively) predicted probability estimates of flying negative events. The Future Orientation subscale did not significantly predict probability estimates. This study is the first to demonstrate probability bias for threat-relevant outcomes in flying phobia. Results suggest that time perspective may influence perceived probability of threat-relevant outcomes but the nature of this relationship remains to be determined.

Evaluating Perceived Probability of Threat-Relevant Outcomes and Temporal Orientation in Flying Phobia

PubMed Central

Mavromoustakos, Elena; Clark, Gavin I.; Rock, Adam J.

2016-01-01

Probability bias regarding threat-relevant outcomes has been demonstrated across anxiety disorders but has not been investigated in flying phobia. Individual temporal orientation (time perspective) may be hypothesised to influence estimates of negative outcomes occurring. The present study investigated whether probability bias could be demonstrated in flying phobia and whether probability estimates of negative flying events was predicted by time perspective. Sixty flying phobic and fifty-five non-flying-phobic adults were recruited to complete an online questionnaire. Participants completed the Flight Anxiety Scale, Probability Scale (measuring perceived probability of flying-negative events, general-negative and general positive events) and the Past-Negative, Future and Present-Hedonistic subscales of the Zimbardo Time Perspective Inventory (variables argued to predict mental travel forward and backward in time). The flying phobic group estimated the probability of flying negative and general negative events occurring as significantly higher than non-flying phobics. Past-Negative scores (positively) and Present-Hedonistic scores (negatively) predicted probability estimates of flying negative events. The Future Orientation subscale did not significantly predict probability estimates. This study is the first to demonstrate probability bias for threat-relevant outcomes in flying phobia. Results suggest that time perspective may influence perceived probability of threat-relevant outcomes but the nature of this relationship remains to be determined. PMID:27557054

Analysis of expression of FLI1 and MMP1 in American cutaneous leishmaniasis caused by Leishmania braziliensis infection

PubMed Central

Almeida, Lucas; Silva, Juliana A.; Andrade, Viviane M.; Machado, Paulo; Jamieson, Sarra E.; Carvalho, Edgar M.

2017-01-01

FLI1 (Friend leukemia virus integration 1) and IL6 (interleukin 6; IL-6) are associated with Leishmania braziliensis susceptibility. Cutaneous lesions show exaggerated matrix metalloproteinase 1 (MMP1). In other skin diseases, FLI1 promoter methylation reduces FLI1 expression, and low FLI1 down-regulates MMP1. IL-6 increases FLI1 expression. We hypothesized that epigenetic regulation of FLI1 in cutaneous leishmaniasis, together with IL-6, might determine MMP1 expression. While generally low (<10%), percent FLI1 promoter methylation was lower (P=0.001) in lesion biopsies than normal skin. Contrary to expectation, a strong positive correlation occurred between FLI1 methylation and gene expression in lesions (r=0.98, P=0.0005) and in IL-6-treated L. braziliensis-infected macrophages (r=0.99, P=0.0004). In silico analysis of the FLI1 promoter revealed co-occurring active H3K27ac and repressive DNA methylation marks to enhance gene expression. FLI1 expression was enhanced between 3 and 24 hours post infection in untreated (P=0.0002) and IL-6-treated (P=0.028) macrophages. MMP1 was enhanced in lesion biopsies (P=0.0002), induced (P=0.007) in infected macrophages, but strongly inhibited by IL-6. No correlations occurred between FLI1 and MMP1 expression in lesions or infected macrophages (with/without IL-6). We conclude that MMP1 is regulated by factors other than FLI1, and that the influence of IL-6 on MMP1 was independent of its effect on FLI1. PMID:28119029

Effective Task Assignment and Motion Planning for Complex UAV Operations

DTIC Science & Technology

2011-09-01

shortest path must be one of the following six different combinations of line segments and curvature arcs: RLR , LRL, RSR, LSL, RSL, LSR, where R is a...RSL, RLR , and their mirror images LSL, LSR, LRL, respectively. This section will discuss the minimum number of waypoints required in order for Dubins...point. Then the vehicle will fly to the third waypoint along it’s turn circle. Lemma 10. For the Dubins trajectories RLR and LRL, three waypoints

River-specific macrogenomic diversity in Simulium guianense s. l. (Diptera: Simuliidae), a complex of tropical American vectors associated with human onchocerciasis

PubMed Central

Hamada, Neusa; Cavalcante do Nascimento, Jeane Marcelle; Grillet, Maria Eugenia

2017-01-01

Simulium guianense Wise is a Latin American vector complex of black flies associated with transmission of the causal agent of human onchocerciasis (river blindness). An analysis of the chromosomal banding patterns of 607 larvae of S. guianense s. l. revealed a high level of variation involving 83 macrogenomic rearrangements across 25 populations in Brazil, French Guiana, and Venezuela. The 25 populations were assigned to 13 cytoforms (A1, A2, B1–B4, C, D, E1–E4, and F), some of which are probably valid species. Based on geographical proximity, a member of the B group of cytoforms probably represents the name-bearing type specimen of S. guianense and the primary vector in the last-remaining onchocerciasis foci in the Western Hemisphere. Cytoform B3 in Amapá State is implicated as an anthropophilic simuliid in an area currently and historically free of onchocerciasis. Distributions of cytoforms are associated with geography, elevation, and drainage basin, and are largely congruent with ecoregions. Despite extraordinarily large larval populations of S. guianense s. l. in big rivers and consequent production of female flies for dispersal, the cytoforms maintain their chromosomal distinction within individual rivers, suggesting a high degree of fidelity to the specialized breeding habitats—rocky shoals—of the natal rivers. PMID:28727841

River-specific macrogenomic diversity in Simulium guianense s. l. (Diptera: Simuliidae), a complex of tropical American vectors associated with human onchocerciasis.

PubMed

Adler, Peter H; Hamada, Neusa; Cavalcante do Nascimento, Jeane Marcelle; Grillet, Maria Eugenia

2017-01-01

Simulium guianense Wise is a Latin American vector complex of black flies associated with transmission of the causal agent of human onchocerciasis (river blindness). An analysis of the chromosomal banding patterns of 607 larvae of S. guianense s. l. revealed a high level of variation involving 83 macrogenomic rearrangements across 25 populations in Brazil, French Guiana, and Venezuela. The 25 populations were assigned to 13 cytoforms (A1, A2, B1-B4, C, D, E1-E4, and F), some of which are probably valid species. Based on geographical proximity, a member of the B group of cytoforms probably represents the name-bearing type specimen of S. guianense and the primary vector in the last-remaining onchocerciasis foci in the Western Hemisphere. Cytoform B3 in Amapá State is implicated as an anthropophilic simuliid in an area currently and historically free of onchocerciasis. Distributions of cytoforms are associated with geography, elevation, and drainage basin, and are largely congruent with ecoregions. Despite extraordinarily large larval populations of S. guianense s. l. in big rivers and consequent production of female flies for dispersal, the cytoforms maintain their chromosomal distinction within individual rivers, suggesting a high degree of fidelity to the specialized breeding habitats-rocky shoals-of the natal rivers.

Ionotropic glutamate receptors IR64a and IR8a form a functional odorant receptor complex in vivo in Drosophila.

PubMed

Ai, Minrong; Blais, Steven; Park, Jin-Yong; Min, Soohong; Neubert, Thomas A; Suh, Greg S B

2013-06-26

Drosophila olfactory sensory neurons express either odorant receptors or ionotropic glutamate receptors (IRs). The sensory neurons that express IR64a, a member of the IR family, send axonal projections to either the DC4 or DP1m glomeruli in the antennal lobe. DC4 neurons respond specifically to acids/protons, whereas DP1m neurons respond to a broad spectrum of odorants. The molecular composition of IR64a-containing receptor complexes in either DC4 or DP1m neurons is not known, however. Here, we immunoprecipitated the IR64a protein from lysates of fly antennal tissue and identified IR8a as a receptor subunit physically associated with IR64a by mass spectrometry. IR8a mutants and flies in which IR8a was knocked down by RNAi in IR64a+ neurons exhibited defects in acid-evoked physiological and behavioral responses. Furthermore, we found that the loss of IR8a caused a significant reduction in IR64a protein levels. When expressed in Xenopus oocytes, IR64a and IR8a formed a functional ion channel that allowed ligand-evoked cation currents. These findings provide direct evidence that IR8a is a subunit that forms a functional olfactory receptor with IR64a in vivo to mediate odor detection.

Flight-test evaluation of STOL control and flight director concepts in a powered-lift aircraft flying curved decelerating approaches

NASA Technical Reports Server (NTRS)

Hindson, W. S.; Hardy, G. H.; Innis, R. C.

1981-01-01

Flight tests were carried out to assess the feasibility of piloted steep curved, and decelerating approach profiles in powered lift STOL aircraft. Several STOL control concepts representative of a variety of aircraft were evaluated in conjunction with suitably designed flight directions. The tests were carried out in a real navigation environment, employed special electronic cockpit displays, and included the development of the performance achieved and the control utilization involved in flying 180 deg turning, descending, and decelerating approach profiles to landing. The results suggest that such moderately complex piloted instrument approaches may indeed be feasible from a pilot acceptance point of view, given an acceptable navigation environment. Systems with the capability of those used in this experiment can provide the potential of achieving instrument operations on curved, descending, and decelerating landing approaches to weather minima corresponding to CTOL Category 2 criteria, while also providing a means of realizing more efficient operations during visual flight conditions.

ASRC Aerospace Corporation Selects Dynamically Reconfigurable Anadigm(Registered Trademark) FPAA For Advanced Data Acquisition System

NASA Technical Reports Server (NTRS)

Mata, Carlos T.

2003-01-01

Anadigm(registered trademark) today announced that ASRC Aerospace Corporation has designed Anadigm's dynamically reconfigurable Field Programmable Analog Array (FPAA) technology into an advanced data acquisition system developed under contract for NASA. ASRC Aerospace designed in the Anadigm(registered trademark) FPAA to provide complex analog signal conditioning in its intelligent, self-calibrating, and self-healing advanced data acquisition system (ADAS). The ADAS has potential applications in industrial, manufacturing, and aerospace markets. This system offers highly reliable operation while reducing the need for user interaction. Anadigm(registered trademark)'s dynamically reconfigurable FPAAs can be reconfigured in-system by the designer or on the fly by a microprocessor. A single device can thus be programmed to implement multiple analog functions and/or to adapt on-the-fly to maintain precision operation despite system degradation and aging. In the case of the ASRC advanced data acquisition system, the FPAA helps ensure that the system will continue to operating at 100% functionality despite changes in the environment, component degradation, and/or component failures.

RGB digital lensless holographic microscopy

NASA Astrophysics Data System (ADS)

Garcia-Sucerquia, Jorge

2013-11-01

The recent introduction of color digital lensless holographic microscopy (CDLHM) has shown the possibility of imaging microscopic specimens at full color without the need of lenses. Owing to the simplicity, robustness, and compactness of the digital lensless holographic microscopes (DLHM), they have been presented as the ideal candidates to being developed into portable holographic microscopes. However, in the case of CDLHM the utilization of three independent lasers hinders the portability option for this microscope. In this contribution an alternative to reduce the complexity of CDLHM aimed to recover the portability of this microscopy technology is presented. A super-bright white-light light-emitting diode (LED) is spectrally and spatially filtered to produce the needed illumination by CDLHM to work. CDLHM with LED illumination is used to image at full color a section of the head of a drosophila melanogaster fly (fruit fly). The LED-CDLHM method shows the capability of imaging objects of 2μm size in comparison with the micrometer resolution reported for LASER-CDLHM.

Experimental evidence that honeybees depress wild insect densities in a flowering crop

PubMed Central

Herbertsson, Lina; Rundlöf, Maj; Bommarco, Riccardo; Smith, Henrik G.

2016-01-01

While addition of managed honeybees (Apis mellifera) improves pollination of many entomophilous crops, it is unknown if it simultaneously suppresses the densities of wild insects through competition. To investigate this, we added 624 honeybee hives to 23 fields of oilseed rape (Brassica napus L.) over 2 years and made sure that the areas around 21 other fields were free from honeybee hives. We demonstrate that honeybee addition depresses the densities of wild insects (bumblebees, solitary bees, hoverflies, marchflies, other flies, and other flying and flower-visiting insects) even in a massive flower resource such as oilseed rape. The effect was independent of the complexity of the surrounding landscape, but increased with the size of the crop field, which suggests that the effect was caused by spatial displacement of wild insects. Our results have potential implications both for the pollination of crops (if displacement of wild pollinators offsets benefits achieved by adding honeybees) and for conservation of wild insects (if displacement results in negative fitness consequences). PMID:27881750

Surgical lesion of the anterior optic tract abolishes polarotaxis in tethered flying locusts, Schistocerca gregaria.

PubMed

Mappes, Martina; Homberg, Uwe

2007-01-01

Many insects can detect the polarization pattern of the blue sky and rely on polarization vision for sky compass orientation. In laboratory experiments, tethered flying locusts perform periodic changes in flight behavior under a slowly rotating polarizer even if one eye is painted black. Anatomical tracing studies and intracellular recordings have suggested that the polarization vision pathway in the locust brain involves the anterior optic tract and tubercle, the lateral accessory lobe, and the central complex of the brain. To investigate whether visual pathways through the anterior optic tract mediate polarotaxis in the desert locust, we transected the tract on one side and tested polarotaxis (1) with both eyes unoccluded and (2) with the eye of the intact hemisphere painted black. In the second group of animals, but not in the first group, polarotaxis was abolished. Sham operations did not impair polarotaxis. The experiments show that the anterior optic tract is an indispensable part of visual pathways mediating polarotaxis in the desert locust.

On-the-fly machine-learning for high-throughput experiments: search for rare-earth-free permanent magnets

PubMed Central

Kusne, Aaron Gilad; Gao, Tieren; Mehta, Apurva; Ke, Liqin; Nguyen, Manh Cuong; Ho, Kai-Ming; Antropov, Vladimir; Wang, Cai-Zhuang; Kramer, Matthew J.; Long, Christian; Takeuchi, Ichiro

2014-01-01

Advanced materials characterization techniques with ever-growing data acquisition speed and storage capabilities represent a challenge in modern materials science, and new procedures to quickly assess and analyze the data are needed. Machine learning approaches are effective in reducing the complexity of data and rapidly homing in on the underlying trend in multi-dimensional data. Here, we show that by employing an algorithm called the mean shift theory to a large amount of diffraction data in high-throughput experimentation, one can streamline the process of delineating the structural evolution across compositional variations mapped on combinatorial libraries with minimal computational cost. Data collected at a synchrotron beamline are analyzed on the fly, and by integrating experimental data with the inorganic crystal structure database (ICSD), we can substantially enhance the accuracy in classifying the structural phases across ternary phase spaces. We have used this approach to identify a novel magnetic phase with enhanced magnetic anisotropy which is a candidate for rare-earth free permanent magnet. PMID:25220062

Technology demonstration of starshade manufacturing for NASA's Exoplanet mission program

NASA Astrophysics Data System (ADS)

Kasdin, N. J.; Lisman, D.; Shaklan, S.; Thomson, M.; Cady, E.; Martin, S.; Marchen, L.; Vanderbei, R. J.; Macintosh, B.; Rudd, R. E.; Savransky, D.; Mikula, J.; Lynch, D.

2012-09-01

It is likely that the coming decade will see the development of a large visible light telescope with enabling technology for imaging exosolar Earthlike planets in the habitable zone of nearby stars. One such technology utilizes an external occulter, a satellite flying far from the telescope and employing a large screen, or starshade, to suppress the incoming starlight suffciently for detecting and characterizing exoplanets. This trades the added complexity of building the precisely shaped starshade and flying it in formation against simplifications in the telescope since extremely precise wavefront control is no longer necessary. In this paper we present the results of our project to design, manufacture, and measure a prototype occulter petal as part of NASA's first Technology Development for Exoplanet Missions program. We describe the mechanical design of the starshade and petal, the precision manufacturing tolerances, and the metrology approach. We demonstrate that the prototype petal meets the requirements and is consistent with a full-size occulter achieving better than 10-10 contrast.

Marbles for the Imagination

NASA Technical Reports Server (NTRS)

Shue, Jack

2004-01-01

The end-to-end test would verify the complex sequence of events from lander separation to landing. Due to the large distances involved and the significant delay time in sending a command and receiving verification, the lander needed to operate autonomously after it separated from the orbiter. It had to sense conditions, make decisions, and act accordingly. We were flying into a relatively unknown set of conditions-a Martian atmosphere of unknown pressure, density, and consistency to land on a surface of unknown altitude, and one which had an unknown bearing strength. In order to touch down safely on Mars the lander had to orient itself for descent and entry, modulate itself to maintain proper lift, pop a parachute, jettison its aeroshell, deploy landing legs and radar, ignite a terminal descent engine, and fly a given trajectory to the surface. Once on the surface, it would determine its orientation, raise the high-gain antenna, perform a sweep to locate Earth, and begin transmitting information. It was this complicated, autonomous sequence that the end-to-end test was to simulate.

SIFamide Translates Hunger Signals into Appetitive and Feeding Behavior in Drosophila.

PubMed

Martelli, Carlotta; Pech, Ulrike; Kobbenbring, Simon; Pauls, Dennis; Bahl, Britta; Sommer, Mirjam Vanessa; Pooryasin, Atefeh; Barth, Jonas; Arias, Carmina Warth Perez; Vassiliou, Chrystalleni; Luna, Abud Jose Farca; Poppinga, Haiko; Richter, Florian Gerhard; Wegener, Christian; Fiala, André; Riemensperger, Thomas

2017-07-11

Animal behavior is, on the one hand, controlled by neuronal circuits that integrate external sensory stimuli and induce appropriate motor responses. On the other hand, stimulus-evoked or internally generated behavior can be influenced by motivational conditions, e.g., the metabolic state. Motivational states are determined by physiological parameters whose homeostatic imbalances are signaled to and processed within the brain, often mediated by modulatory peptides. Here, we investigate the regulation of appetitive and feeding behavior in the fruit fly, Drosophila melanogaster. We report that four neurons in the fly brain that release SIFamide are integral elements of a complex neuropeptide network that regulates feeding. We show that SIFamidergic cells integrate feeding stimulating (orexigenic) and feeding suppressant (anorexigenic) signals to appropriately sensitize sensory circuits, promote appetitive behavior, and enhance food intake. Our study advances the cellular dissection of evolutionarily conserved signaling pathways that convert peripheral metabolic signals into feeding-related behavior. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Gastrointestinal stem cells in health and disease: from flies to humans

PubMed Central

Li, Hongjie; Jasper, Heinrich

2016-01-01

ABSTRACT The gastrointestinal tract of complex metazoans is highly compartmentalized. It is lined by a series of specialized epithelia that are regenerated by specific populations of stem cells. To maintain tissue homeostasis, the proliferative activity of stem and/or progenitor cells has to be carefully controlled and coordinated with regionally distinct programs of differentiation. Metaplasias and dysplasias, precancerous lesions that commonly occur in the human gastrointestinal tract, are often associated with the aberrant proliferation and differentiation of stem and/or progenitor cells. The increasingly sophisticated characterization of stem cells in the gastrointestinal tract of mammals and of the fruit fly Drosophila has provided important new insights into these processes and into the mechanisms that drive epithelial dysfunction. In this Review, we discuss recent advances in our understanding of the establishment, maintenance and regulation of diverse intestinal stem cell lineages in the gastrointestinal tract of Drosophila and mice. We also discuss the field's current understanding of the pathogenesis of epithelial dysfunctions. PMID:27112333

Angular velocity integration in a fly heading circuit

PubMed Central

Turner-Evans, Daniel; Wegener, Stephanie; Rouault, Hervé; Franconville, Romain; Wolff, Tanya; Seelig, Johannes D; Druckmann, Shaul; Jayaraman, Vivek

2017-01-01

Many animals maintain an internal representation of their heading as they move through their surroundings. Such a compass representation was recently discovered in a neural population in the Drosophila melanogaster central complex, a brain region implicated in spatial navigation. Here, we use two-photon calcium imaging and electrophysiology in head-fixed walking flies to identify a different neural population that conjunctively encodes heading and angular velocity, and is excited selectively by turns in either the clockwise or counterclockwise direction. We show how these mirror-symmetric turn responses combine with the neurons’ connectivity to the compass neurons to create an elegant mechanism for updating the fly’s heading representation when the animal turns in darkness. This mechanism, which employs recurrent loops with an angular shift, bears a resemblance to those proposed in theoretical models for rodent head direction cells. Our results provide a striking example of structure matching function for a broadly relevant computation. DOI: http://dx.doi.org/10.7554/eLife.23496.001 PMID:28530551

[Importance of competition for pollination in formation of the entomophylous plants complex structure].

PubMed

Dlusskiĭ, G M

2013-01-01

Many species of entomophylous plants have a wide range of pollinators, and the same insects visit flowers of many plants. The competition for pollination leads to decreasing in seed production of competing species. However, there exists a variety of adaptations that allow plants to reduce the intensity of competition. A comparative analysis of pollinators spectra has allowed to designate groups (subcomplexes) of plants with regard to dominance of various groups of pollinators: myiophylous (flies from the superfamily Muscomorha dominate), syphidophylous (flies from the family Syrphidae dominate), psychophylous (butterflies dominate), cantharophylous (beetles dominate), nonspecialized and specialized melittophylous (Apidae, mainly bumblebees, dominate). The belonging of plants to a specific subcomplex is defined mainly by the structure of flowers and inflorescences. Modes of mechanical and attractive isolation are discussed that lead to restriction of pollinators composition. Competition abatement between species with similar spectra of pollinators and belonging to the same subcomplex is achieved mainly by spatial (ecological) and temporal (different timing of flowering) isolation.

How the zebra got its stripes: a problem with too many solutions

PubMed Central

Larison, Brenda; Harrigan, Ryan J.; Thomassen, Henri A.; Rubenstein, Daniel I.; Chan-Golston, Alec M.; Li, Elizabeth; Smith, Thomas B.

2015-01-01

The adaptive significance of zebra stripes has thus far eluded understanding. Many explanations have been suggested, including social cohesion, thermoregulation, predation evasion and avoidance of biting flies. Identifying the associations between phenotypic and environmental factors is essential for testing these hypotheses and substantiating existing experimental evidence. Plains zebra striping pattern varies regionally, from heavy black and white striping over the entire body in some areas to reduced stripe coverage with thinner and lighter stripes in others. We examined how well 29 environmental variables predict the variation in stripe characteristics of plains zebra across their range in Africa. In contrast to recent findings, we found no evidence that striping may have evolved to escape predators or avoid biting flies. Instead, we found that temperature successfully predicts a substantial amount of the stripe pattern variation observed in plains zebra. As this association between striping and temperature may be indicative of multiple biological processes, we suggest that the selective agents driving zebra striping are probably multifarious and complex. PMID:26064590

Caffeine promotes wakefulness via dopamine signaling in Drosophila

PubMed Central

Nall, Aleksandra H.; Shakhmantsir, Iryna; Cichewicz, Karol; Birman, Serge; Hirsh, Jay; Sehgal, Amita

2016-01-01

Caffeine is the most widely-consumed psychoactive drug in the world, but our understanding of how caffeine affects our brains is relatively incomplete. Most studies focus on effects of caffeine on adenosine receptors, but there is evidence for other, more complex mechanisms. In the fruit fly Drosophila melanogaster, which shows a robust diurnal pattern of sleep/wake activity, caffeine reduces nighttime sleep behavior independently of the one known adenosine receptor. Here, we show that dopamine is required for the wake-promoting effect of caffeine in the fly, and that caffeine likely acts presynaptically to increase dopamine signaling. We identify a cluster of neurons, the paired anterior medial (PAM) cluster of dopaminergic neurons, as the ones relevant for the caffeine response. PAM neurons show increased activity following caffeine administration, and promote wake when activated. Also, inhibition of these neurons abrogates sleep suppression by caffeine. While previous studies have focused on adenosine-receptor mediated mechanisms for caffeine action, we have identified a role for dopaminergic neurons in the arousal-promoting effect of caffeine. PMID:26868675

Exploring a strongly non-Markovian behavior

NASA Astrophysics Data System (ADS)

Alba, Vasyl; Berman, Gordon; Bialek, William; Shaevitz, Joshua

Is there some simplicity or universality underlying the complexities of natural animal behavior? Using the walking fruit fly as a model system, we have shown that unconstrained behaviors can be categorized into roughly one hundred discrete states, which all individuals from a single species visit repeatedly. In each state, the fly executes stereotyped movements, and the transitions between states are organized hierarchically. The sequences of states, however, are strongly non-Markovian: correlations persist for orders of magnitude longer than expected from the state-to-state transition probabilities, and there are hints of power law decay. But with 100 states, further analysis is difficult. Here we develop a generalization of the information bottleneck method to compress these states into a more compact description that preserves as much of the temporal correlations as possible. We find that, even on compressing down to just two states, this coarse grained description of behavior captures the long ranged correlations. Power law decays are clearer in this reduced representation, which opens the way for more quantitative analysis.

Microstructural and Microanalytical Study on Concrete Exposed to the Sulfate Environment

NASA Astrophysics Data System (ADS)

Qing, Fang; Beixing, Li; Jiangang, Yin; Xiaolu, Yuan

2017-11-01

Microstructural properties have been examined to investigate the effect of mineral admixtures on the sulfate resistance of concrete. Concrete and cement paste specimens made with ordinary Portland cement (OPC) or ordinary Portland cement incorporating 20% fly ash (FA) or 30% ground blast furnace slag (GBFS), were made and exposed to 250 cycles of the cyclic sulfate environment. Microstructural and Microanalytical study was conducted by means of x-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and mercury intrusion porosimetry (MIP). Results indicate that the pore structure of concrete after sulfate exposure possesses the fractal feature. The OPC concrete presents more complex pore internal surface, higher porosity and less micro-pores than the concrete incorporating fly ash and GBFS. Portlandite in OPC concrete and OPC-FA concrete is mainly converted to gypsum; while for OPC-GBFS concrete, both gypsum and ettringite are formed. In the cyclic sulfate environment, repeated hydration and dehydration of sulfates produce the expansive stress in pores, aggravating the demolishment of concrete structure.

Identification of genes involved in the biology of atypical teratoid/rhabdoid tumours using Drosophila melanogaster

NASA Astrophysics Data System (ADS)

Jeibmann, Astrid; Eikmeier, Kristin; Linge, Anna; Kool, Marcel; Koos, Björn; Schulz, Jacqueline; Albrecht, Stefanie; Bartelheim, Kerstin; Frühwald, Michael C.; Pfister, Stefan M.; Paulus, Werner; Hasselblatt, Martin

2014-06-01

Atypical teratoid/rhabdoid tumours (AT/RT) are malignant brain tumours. Unlike most other human brain tumours, AT/RT are characterized by inactivation of one single gene, SMARCB1. SMARCB1 is a member of the evolutionarily conserved SWI/SNF chromatin remodelling complex, which has an important role in the control of cell differentiation and proliferation. Little is known, however, about the pathways involved in the oncogenic effects of SMARCB1 inactivation, which might also represent targets for treatment. Here we report a comprehensive genetic screen in the fruit fly that revealed several genes not yet associated with loss of snr1, the Drosophila homologue of SMARCB1. We confirm the functional role of identified genes (including merlin, kibra and expanded, known to regulate hippo signalling pathway activity) in human rhabdoid tumour cell lines and AT/RT tumour samples. These results demonstrate that fly models can be employed for the identification of clinically relevant pathways in human cancer.

Experimental evidence that honeybees depress wild insect densities in a flowering crop.

PubMed

Lindström, Sandra A M; Herbertsson, Lina; Rundlöf, Maj; Bommarco, Riccardo; Smith, Henrik G

2016-11-30

While addition of managed honeybees (Apis mellifera) improves pollination of many entomophilous crops, it is unknown if it simultaneously suppresses the densities of wild insects through competition. To investigate this, we added 624 honeybee hives to 23 fields of oilseed rape (Brassica napus L.) over 2 years and made sure that the areas around 21 other fields were free from honeybee hives. We demonstrate that honeybee addition depresses the densities of wild insects (bumblebees, solitary bees, hoverflies, marchflies, other flies, and other flying and flower-visiting insects) even in a massive flower resource such as oilseed rape. The effect was independent of the complexity of the surrounding landscape, but increased with the size of the crop field, which suggests that the effect was caused by spatial displacement of wild insects. Our results have potential implications both for the pollination of crops (if displacement of wild pollinators offsets benefits achieved by adding honeybees) and for conservation of wild insects (if displacement results in negative fitness consequences). © 2016 The Author(s).

Improved capture of stable flies (Diptera: Muscidae) by placement of Knight Stick sticky fly traps protected by electric fence inside animal exhibit yards at the Smithsonian’s National Zoological Park

USDA-ARS?s Scientific Manuscript database

The stable fly is a blood-feeding pest of livestock and other animals. Traps have been used to survey stable flies and reduce populations. The Knight Stick trap is highly effective for catching stable flies and may catch more if limits on trap placement were relaxed. When working on stable fly contr...

Host association and the capacity of sand flies as vectors of lizard malaria in Panama.

PubMed

Kimsey, R B

1992-08-01

In this paper the capacity of sand flies (Lutzomyia) as vectors of parasites that cause malaria in anoles (Anolis limifrons) in the Zona de Canal, Panama was investigated. Inhabiting all study plots, often in local abundance, L. trinidadensis emerged as the principal candidate sand fly vector; the results of surveys did not suggest a likely mosquito vector. Although L. trinidadensis and infected anoles co-inhabited all plots, their abundances seemed unrelated. No evidence that sand flies parasitized anoles was uncovered. As anole activity patterns in daylight reciprocate with those of sand flies and at night anoles seem to avoid locations that sand flies frequent, anoles may evade sand fly bites altogether. Further, these sand flies occurred in close numerical and ecological association with Thecadactylus rapicauda, a reclusive moist forest gecko, often parasitizing these hosts in large numbers. Thus, sand flies lack capacity as vectors of malaria-causing parasites in central Panamanian anoles.

Temperature Effects on Olive Fruit Fly Infestation in the FlySim Cellular Automata Model

NASA Astrophysics Data System (ADS)

Bruno, Vincenzo; Baldacchini, Valerio; di Gregorio, Salvatore

FlySim is a Cellular Automata model developed for simulating infestation of olive fruit flies (Bactrocera Oleae) on olive (Olea europaea) groves. The flies move into the groves looking for mature olives where eggs are spawn. This serious agricultural problem is mainly tackled by using chemical agents at the first signs of the infestation, but organic productions with no or few chemicals are strongly requested by the market. Oil made with infested olives is poor in quality, nor olives are suitable for selling in stores. The FlySim model simulates the diffusion of flies looking for mature olives and the growing of flies due to atmospheric conditions. Foreseeing an infestation is the best way to prevent it and to reduce the need of chemicals in agriculture. In this work we investigated the effects of temperature on olive fruit flies and resulting infestation during late spring and summer.

Fly ash carbon passivation

DOE Office of Scientific and Technical Information (OSTI.GOV)

La Count, Robert B; Baltrus, John P; Kern, Douglas G

A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most ofmore » the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.« less

Improved capture of stable flies (Diptera: Muscidae) by placement of knight stick sticky fly traps protected by electric fence inside animal exhibit yards at the Smithsonian's National Zoological Park.

PubMed

Hogsette, Jerome A; Ose, Gregory A

2017-12-01

Stable flies are noxious blood-feeding pests of exotic animals at zoological parks, inflicting painful bites, and causing discomfort to animals. Stable fly management is difficult because of the flies' tendency to remain on the host animals only when feeding. Non-toxic traps can be efficient but traps placed around exhibit perimeters captured fewer-than-expected numbers of flies. By surrounding traps with square electric fence enclosures, traps could be placed in the exhibits with the host animals and compared with an equal number of traps placed along perimeter fences. During a 21-week study, traps inside exhibits captured 5× more stable flies than traps placed along exhibit perimeters. Traps inside exhibits tended to show more fluctuations in fly populations than traps along perimeters. The increased numbers of flies captured using this technique should provide relief from this pestiferous fly and greatly improve animal health and welfare. We believe this to be the first study where traps were used to capture stable flies in exhibit yards at a zoological park. © 2017 The Authors. Zoo Biology Published by Wiley Periodicals, Inc.

Mechanical transmission of turkey coronavirus by domestic houseflies (Musca domestica Linnaeaus).

PubMed

Calibeo-Hayes, Dawn; Denning, Steve S; Stringham, S M; Guy, James S; Smith, Lynda G; Watson, D Wes

2003-01-01

Domestic houseflies (Musca domestica Linnaeaus) were examined for their ability to harbor and transmit turkey coronavirus (TCV). Laboratory-reared flies were experimentally exposed to TCV by allowing flies to imbibe an inoculum comprised of turkey embryo-propagated virus (NC95 strain). TCV was detected in dissected crops from exposed flies for up to 9 hr postexposure; no virus was detected in crops of sham-exposed flies. TCV was not detected in dissected intestinal tissues collected from exposed or sham-exposed flies at any time postexposure. The potential of the housefly to directly transmit TCV to live turkey poults was examined by placing 7-day-old turkey poults in contact with TCV-exposed houseflies 3 hr after flies consumed TCV inoculum. TCV infection was detected in turkeys placed in contact with TCV-exposed flies at densities as low as one fly/bird (TCV antigens detected at 3 days post fly contact in tissues of 3/12 turkeys); however, increased rates of infection were observed with higher fly densities (TCV antigens detected in 9/12 turkeys after contact with 10 flies/bird). This study demonstrates the potential of the housefly to serve as a mechanical vector of TCV.

Treatment of fly ash from power plants using thermal plasma.

PubMed

Al-Mayman, Sulaiman; AlShunaifi, Ibrahim; Albeladi, Abdullah; Ghiloufi, Imed; Binjuwair, Saud

2017-01-01

Fly ash from power plants is very toxic because it contains heavy metals. In this study fly ash was treated with a thermal plasma. Before their treatment, the fly ash was analyzed by many technics such as X-ray fluorescence, CHN elemental analysis, inductively coupled plasma atomic emission spectroscopy and scanning electron microscopy. With these technics, the composition, the chemical and physical proprieties of fly ash are determined. The results obtained by these analysis show that fly ash is mainly composed of carbon, and it contains also sulfur and metals such as V, Ca, Mg, Na, Fe, Ni, and Rh. The scanning electron microscopy analysis shows that fly ash particles are porous and have very irregular shapes with particle sizes of 20-50 μm. The treatment of fly ash was carried out in a plasma reactor and in two steps. In the first step, fly ash was treated in a pyrolysis/combustion plasma system to reduce the fraction of carbon. In the second step, the product obtained by the combustion of fly ash was vitrified in a plasma furnace. The leaching results show that the fly ash was detoxified by plasma vitrification and the produced slag is amorphous and glassy.

Treatment of fly ash from power plants using thermal plasma

PubMed Central

Al-Mayman, Sulaiman; AlShunaifi, Ibrahim; Albeladi, Abdullah; Binjuwair, Saud

2017-01-01

Fly ash from power plants is very toxic because it contains heavy metals. In this study fly ash was treated with a thermal plasma. Before their treatment, the fly ash was analyzed by many technics such as X-ray fluorescence, CHN elemental analysis, inductively coupled plasma atomic emission spectroscopy and scanning electron microscopy. With these technics, the composition, the chemical and physical proprieties of fly ash are determined. The results obtained by these analysis show that fly ash is mainly composed of carbon, and it contains also sulfur and metals such as V, Ca, Mg, Na, Fe, Ni, and Rh. The scanning electron microscopy analysis shows that fly ash particles are porous and have very irregular shapes with particle sizes of 20–50 μm. The treatment of fly ash was carried out in a plasma reactor and in two steps. In the first step, fly ash was treated in a pyrolysis/combustion plasma system to reduce the fraction of carbon. In the second step, the product obtained by the combustion of fly ash was vitrified in a plasma furnace. The leaching results show that the fly ash was detoxified by plasma vitrification and the produced slag is amorphous and glassy. PMID:28546898

Proteus mirabilis interkingdom swarming signals attract blow flies

PubMed Central

Ma, Qun; Fonseca, Alicia; Liu, Wenqi; Fields, Andrew T; Pimsler, Meaghan L; Spindola, Aline F; Tarone, Aaron M; Crippen, Tawni L; Tomberlin, Jeffery K; Wood, Thomas K

2012-01-01

Flies transport specific bacteria with their larvae that provide a wider range of nutrients for those bacteria. Our hypothesis was that this symbiotic interaction may depend on interkingdom signaling. We obtained Proteus mirabilis from the salivary glands of the blow fly Lucilia sericata; this strain swarmed significantly and produced a strong odor that attracts blow flies. To identify the putative interkingdom signals for the bacterium and flies, we reasoned that as swarming is used by this bacterium to cover the food resource and requires bacterial signaling, the same bacterial signals used for swarming may be used to communicate with blow flies. Using transposon mutagenesis, we identified six novel genes for swarming (ureR, fis, hybG, zapB, fadE and PROSTU_03490), then, confirming our hypothesis, we discovered that fly attractants, lactic acid, phenol, NaOH, KOH and ammonia, restore swarming for cells with the swarming mutations. Hence, compounds produced by the bacterium that attract flies also are utilized for swarming. In addition, bacteria with the swarming mutation rfaL attracted fewer blow flies and reduced the number of eggs laid by the flies. Therefore, we have identified several interkingdom signals between P. mirabilis and blow flies. PMID:22237540

Influence of Cements Containing Calcareous Fly Ash as a Main Component Properties of Fresh Cement Mixtures

NASA Astrophysics Data System (ADS)

Gołaszewski, Jacek; Kostrzanowska-Siedlarz, Aleksandra; Ponikiewski, Tomasz; Miera, Patrycja

2017-10-01

The main goal of presented research was to examine usability of cements containing calcareous fly ash (W) from technological point of view. In the paper the results of tests concerning the influence of CEM II and CEM IV cements containing fly ash (W) on rheological properties, air content, setting times and plastic shrinkage of mortars are presented and discussed. Moreover, compatibility of plasticizers with cements containing fly ash (W) was also studied. Additionally, setting time and hydration heat of cements containing calcareous fly ash (W) were determined. In a broader aspect, the research contributes to promulgation of the possibility of using calcareous fly ash (W) in cement and concrete technology, what greatly benefits the environment protection (utilization of waste fly ash). Calcareous fly ash can be used successfully as the main component of cement. Cements produced by blending with processed fly ash or cements produced by interginding are characterized by acceptable technological properties. In respect to CEM I cements, cements containing calcareous fly ash worsen workability, decrease air content, delay setting time of mixtures. Cements with calcareous fly ash show good compatibility with plasticizers.

Comparison of Anastrepha ludens (Diptera: Tephritidae) Bisexual and Genetic Sexing (Tapachula-7) Strains: Effect of Hypoxia, Fly Density, Chilling Period, and Food Type on Fly Quality.

PubMed

Arredondo, José; Ruiz, Lía; Hernández, Emilio; Montoya, Pablo; Díaz-Fleischer, Francisco

2016-04-01

The use of genetic sexing strain (GSS) insects in the sterile insect technique (SIT) makes necessary the revision of quality parameters of some stressful steps used during the packing process for aerial release because of possible differences in tolerance between fly strains. Here, we determined the effect of three periods of hypoxia (12, 24, and 36 h at pupal stage), three cage densities (1.0, 1.3, and 1.5 flies/cm2), two different foods (protein/sugar (1/24) and Mubarqui), and three chilling times (20 min [control], 90, and 180 min) on the quality parameters of flies of two Anastrepha ludens (Loew) strains (bisexual and GSS Tapachula-7). In general, the response to stressful conditions of both fly strains was qualitatively equivalent but quantitatively different, as flies of both strains responded equally to the stressful factors; however, flies of Tapachula-7 exhibited lower quality parameters than the control flies. Thus, hypoxia affected the flying ability but not the emergence or longevity of flies. The food type affected the adult weight; protein/sugar produced heavier flies that also survived longer and had a greater mating propensity. Flies under the lowest density were better fliers that those at the other two densities. Increasing chilling time reduced flight ability but not longevity or mating propensity. The implications of these findings for the use of A. ludens GSS in SIT programs are discussed herein.

Evaluation of imidacloprid-treated traps as an attract and kill system for filth flies during contingency operations.

PubMed

Dunford, James C; Hoel, David F; Hertz, Jeffrey C; England, David B; Dunford, Kelly R; Stoops, Craig A; Szumlas, Daniel E; Hogsette, Jerome A

2013-01-01

Two field trials were conducted to evaluate if filth fly trap efficacy was increased by augmentation with an insecticide application to the trap's exterior. Four Fly Terminator Pro traps (Farnam Companies, Inc, Phoenix, AZ) baited with Terminator Fly Attractant (in water) were suspended on polyvinyl chloride pipe framing at a municipal waste transfer site in Clay County, Florida. The outer surfaces of 2 traps were treated with Maxforce Fly Spot Bait (Bayer Environmental Science, Research Triangle Park, NC) (10% imidacloprid) to compare kill rates between treated and untreated traps. Kill consisted of total flies collected from inside traps and from mesh nets suspended beneath all traps, both treated and untreated. Each of 2 treated and untreated traps was rotated through 4 trap sites every 24 hrs. In order to evaluate operational utility and conservation of supplies during remote contingency operations, fly attractant remained in traps for the duration of the first trial but was changed daily during the second trial (following manufacturer's recommendations). In addition, ½ strength Terminator Fly Attractant was used during the first trial and traps were set at full strength during the second trial. Flies collected within the traps and in mesh netting were counted and identified. Three species, Musca domestica (L.), Chrysomya megacephala (F.), and Lucilia cuprina (Wiedemann), comprised the majority of samples in both trials. The net samples recovered more flies when the outer surface was treated with imidacloprid, however, treated traps collected fewer flies inside the trap than did untreated traps for both trials. No significant statistical advantage was found in treating Fly Terminator Pro trap exteriors with Maxforce Fly Spot Bait. However, reducing manufacturer's recommended strength of Terminator Fly Attractant showed similar results to traps set at full strength. Treating the outer surfaces may improve kill of fly species that do not enter the trap. Terminator Fly Attractant was also found to be more effective if traps were not changed daily and left to hold dead flies for longer periods.