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Sample records for flying squirrel petaurista

  1. Ultrasonic vocalizations emitted by flying squirrels.

    Directory of Open Access Journals (Sweden)

    Meghan N Murrant

    Full Text Available Anecdotal reports of ultrasound use by flying squirrels have existed for decades, yet there has been little detailed analysis of their vocalizations. Here we demonstrate that two species of flying squirrel emit ultrasonic vocalizations. We recorded vocalizations from northern (Glaucomys sabrinus and southern (G. volans flying squirrels calling in both the laboratory and at a field site in central Ontario, Canada. We demonstrate that flying squirrels produce ultrasonic emissions through recorded bursts of broadband noise and time-frequency structured frequency modulated (FM vocalizations, some of which were purely ultrasonic. Squirrels emitted three types of ultrasonic calls in laboratory recordings and one type in the field. The variety of signals that were recorded suggest that flying squirrels may use ultrasonic vocalizations to transfer information. Thus, vocalizations may be an important, although still poorly understood, aspect of flying squirrel social biology.

  2. Conserved microsatellite markers of high cross-species utility for flying, ground and tree squirrels

    OpenAIRE

    Jumpa, S.; Dawson, D. A.; Horsburgh, G.J.; Walton, C

    2015-01-01

    Many squirrel species around the world are threatened by forest loss and fragmentation. To facilitate studies of squirrel biodiversity, particularly of flying squirrels in Southeast Asia, we identified Hylopetes, Menetes, Glaucomys and Sciurus squirrel microsatellite sequences with homologs in a second squirrel species (Spermophilus tridecemlineatus), designed 40 consensus markers and tested three squirrel species. When tested in four individuals per species, 26 markers were variable in Hylop...

  3. Evolution of genome organizations of squirrels (Sciuridae) revealed by cross-species chromosome painting.

    Science.gov (United States)

    Li, Tangliang; O'Brien, Patricia C M; Biltueva, Larisa; Fu, Beiyuan; Wang, Jinhuan; Nie, Wenhui; Ferguson-Smith, Malcolm A; Graphodatsky, Alexander S; Yang, Fengtang

    2004-01-01

    With complete sets of chromosome-specific painting probes derived from flow-sorted chromosomes of human and grey squirrel (Sciurus carolinensis), the whole genome homologies between human and representatives of tree squirrels (Sciurus carolinensis, Callosciurus erythraeus), flying squirrels (Petaurista albiventer) and chipmunks (Tamias sibiricus) have been defined by cross-species chromosome painting. The results show that, unlike the highly rearranged karyotypes of mouse and rat, the karyotypes of squirrels are highly conserved. Two methods have been used to reconstruct the genome phylogeny of squirrels with the laboratory rabbit (Oryctolagus cuniculus) as the out-group: (1) phylogenetic analysis by parsimony using chromosomal characters identified by comparative cytogenetic approaches; (2) mapping the genome rearrangements onto recently published sequence-based molecular trees. Our chromosome painting results, in combination with molecular data, show that flying squirrels are phylogenetically close to New World tree squirrels. Chromosome painting and G-banding comparisons place chipmunks (Tamias sibiricus ), with a derived karyotype, outside the clade comprising tree and flying squirrels. The superorder Glires (orde Rodentia + order Lagomorpha) is firmly supported by two conserved syntenic associations between human chromosomes 1 and 10p homologues, and between 9 and 11 homologues.

  4. Differential Estimates of Southern Flying Squirrel (Glaucomys volans) Population Structure Based on Capture Method.

    Energy Technology Data Exchange (ETDEWEB)

    Laves, Kevin S.; Loeb, Susan C.

    2006-01-01

    ABSTRACT.—It is commonly assumed that population estimates derived from trapping small mammals are accurate and unbiased or that estimates derived from different capture methods are comparable. We captured southern flying squirrels (Glaucomys volans) using two methods to study their effect on red-cockaded woodpecker (Picoides borealis) reproductive success. Southern flying squirrels were captured at and removed from 30 red-cockaded woodpecker cluster sites during March to July 1994 and 1995 using Sherman traps placed in a grid encompassing a red-cockaded woodpecker nest tree and by hand from red-cockaded woodpecker cavities. Totals of 195 (1994) and 190 (1995) red-cockaded woodpecker cavities were examined at least three times each year. Trappability of southern flying squirrels in Sherman traps was significantly greater in 1995 (1.18%; 22,384 trap nights) than in 1994 (0.42%; 20,384 trap nights), and capture rate of southern flying squirrels in cavities was significantly greater in 1994 (22.7%; 502 cavity inspections) than in 1995 (10.8%; 555 cavity inspections). However, more southern flying squirrels were captured per cavity inspection than per Sherman trap night in both years. Male southern flying squirrels were more likely to be captured from cavities than in Sherman traps in 1994, but not in 1995. Both male and female juveniles were more likely to be captured in cavities than in traps in both years. In 1994 males in reproductive condition were more likely to be captured in cavities than in traps and in 1995 we captured significantly more reproductive females in cavities than in traps. Our data suggest that population estimates based solely on one trapping method may not represent true population size or structure of southern flying squirrels.

  5. Differential estimates of southern flying squirrel (Glaucomys volans) population structure based on capture method

    Science.gov (United States)

    Kevin S. Laves; Susan C. Loeb

    2005-01-01

    It is commonly assumed that population estimates derived from trapping small mammals are accurate and unbiased or that estimates derived from different capture methods are comparable. We captured southern flying squirrels (Glaucmrtys volam) using two methods to study their effect on red-cockaded woodpecker (Picoides bumah) reproductive success. Southern flying...

  6. Red-cockaded woodpecker nesting success, forest structure, and southern flying squirrels in Texas

    Science.gov (United States)

    Richard N. Conner; D. Craig Rudolph; Daniel Saenz; Richard R. Schaefer

    1996-01-01

    For several decades general opinion has suggested that southern flying squirrels (Gluucomys volans) have a negative effect on Red-cockaded Woodpeckers (Picoides borealis) through competition for cavities and egg/nestling predation. Complete removal of hardwood trees from Red-cockaded Woodpecker cavity tree clusters has occurred on some forests because southern flying...

  7. Demography of northern flying squirrels informs ecosystem management of western interior forests.

    Science.gov (United States)

    Lehmkuhl, John F; Kistler, Keith D; Begley, James S; Boulanger, John

    2006-04-01

    We studied northern flying squirrel (Glaucomys sabrinus) demography in the eastern Washington Cascade Range to test hypotheses about regional and local abundance patterns and to inform managers of the possible effects of fire and fuels management on flying squirrels. We quantified habitat characteristics and squirrel density, population trends, and demography in three typical forest cover types over a four-year period. We had 2034 captures of flying squirrels over 41 000 trap nights from 1997 through 2000 and marked 879 squirrels for mark-recapture population analysis. Ponderosa pine (Pinus ponderosa) forest appeared to be poorer habitat for flying squirrels than young or mature mixed-conifer forest. About 35% fewer individuals were captured in open pine forest than in dry mixed-conifer Douglas-fir (Pseudotsuga menziesii) and grand fir (Abies grandis) forests. Home ranges were 85% larger in pine forest (4.6 ha) than in mixed-conifer forests (2.5 ha). Similarly, population density (Huggins estimator) in ponderosa pine forest was half (1.1 squirrels/ha) that of mixed-conifer forest (2.2 squirrels/ha). Tree canopy cover was the single best correlate of squirrel density (r = 0.77), with an apparent threshold of 55% canopy cover separating stands with low- from high-density populations. Pradel estimates of annual recruitment were lower in open pine (0.28) than in young (0.35) and mature (0.37) forest. High recruitment was most strongly associated with high understory plant species richness and truffle biomass. Annual survival rates ranged from 45% to 59% and did not vary among cover types. Survival was most strongly associated with understory species richness and forage lichen biomass. Maximum snow depth had a strong negative effect on survival. Rate of per capita increase showed a density-dependent response. Thinning and prescribed burning in ponderosa pine and dry mixed conifer forests to restore stable fire regimes and forest structure might reduce flying squirrel

  8. Effects of southern flying squirrels Glaucomys volans on red-cockaded woodpecker Picoides borealis reproductive success

    Science.gov (United States)

    Kevin S. Laves; Susan C. Loeb

    1999-01-01

    Anecdotal data gathered from many populations suggest that southern flying squirrel (SFS, Glaucomys volans) use of the endangered red-cockaded woodpecker's (RCW, Picoides borealis) nest and roost cavities may negatively affect RCW populations. The authors conducted a controlled experiment to determine the effects of SFS’s on...

  9. Kinematics of turning maneuvers in the southern flying squirrel, Glaucomys volans.

    Science.gov (United States)

    Bishop, Kristin L; Brim-Deforest, Whitney

    2008-06-01

    The ability to change direction is essential to any animal that moves around in a complex, 3D environment. In this study we present the first 3D description of body positions during gliding turns in a mammalian gliding specialist, the southern flying squirrel, Glaucomys volans. In addition, we used these kinematic data to estimate the aerodynamic forces generated by the animals and rotational velocities and accelerations of the body while turning. These results were compared with similar measurements of flying squirrels during straight glides. The two individuals used in this study differed significantly in limb position asymmetries between the two sides of their bodies and also were significantly different in measures of turning performance. The individual with better performance used limb positions consistent with a primarily lift-based turning mechanism (banked turn), whereas the individual with poorer performance used limb positions consistent with a primarily drag-based turning mechanism (crabbed turn). Both individuals employed limb movements continuously through the gliding turn, but these movements did not have any consistent relationships with body rotations or lateral acceleration. As compared with straight glides, squirrels used significantly higher angles of attack and had lower lift-to-drag ratios, but did not differ in glide angle. Contrary to the typical view of maneuvering during gliding as a simple, static form of locomotion, the results presented here indicate that mammalian gliding is a complex behavior comprising the interplay of many components of limb position and wing shape that affect the balance of forces that control the turn.

  10. Thinning of young Douglas-fir forests decreases density of northern flying squirrels in the Oregon Cascades

    Science.gov (United States)

    Manning, Tom; Hagar, Joan C.; McComb, Brenda C.

    2012-01-01

    Large-scale commercial thinning of young forests in the Pacific Northwest is currently promoted on public lands to accelerate the development of late-seral forest structure for the benefit of wildlife species such as northern spotted owls (Strix occidentalis caurina) and their prey, including the northern flying squirrel (Glaucomys sabrinus). Attempts to measure the impact of commercial thinning on northern flying squirrels have mostly addressed short-term effects (2–5 years post-thinning) and the few published studies of longer-term results have been contradictory. We measured densities of northern flying squirrels 11–13 years after thinning of young (55–65 years) Douglas-fir forest stands in the Cascade Range of Oregon, as part of the Young Stand Thinning & Diversity Study. The study includes four replicate blocks, each consisting of an unthinned control stand and one stand each of the following thinning treatments: Heavy Thin; Light Thin; and Light Thin with Gaps. Thinning decreased density of northern flying squirrels, and squirrel densities were significantly lower in heavily thinned stands than in more lightly thinned stands. Regression analysis revealed a strong positive relationship of flying squirrel density with density of large (>30 cm diameter) standing dead trees and a negative relationship with percent cover of low understory shrubs. Maintaining sufficient area and connectivity of dense, closed canopy forest is recommended as a strategy to assure that long-term goals of promoting late-seral structure do not conflict with short-term habitat requirements of this important species.

  11. Area occupancy and detection probabilities of the Virginia northern flying squirrel (Glaucomys sabrinus fuscus) using nest-box surveys

    Science.gov (United States)

    W. Mark Ford; Kurtis R. Moseley; Craig W. Stihler; John W. Edwards

    2010-01-01

    Concomitant with the delisting of the endangered Virginia northern flying squirrel (Glaucomys sabrinus fuscus) in 2008, the U.S. Fish and Wildlife Service mandated a 10-year post-delisting monitoring effort to ensure that subspecies population and distribution stability will persist following a changed regulatory status. Although criticized for the...

  12. Predictive habitat models derived from nest-box occupancy for the endangered Carolina northern flying squirrel in the southern Appalachians

    Science.gov (United States)

    Ford, W. Mark; Evans, A.M.; Odom, Richard H.; Rodrigue, Jane L.; Kelly, C.A.; Abaid, Nicole; Diggins, Corinne A.; Newcomb, Doug

    2016-01-01

    In the southern Appalachians, artificial nest-boxes are used to survey for the endangered Carolina northern flying squirrel (CNFS; Glaucomys sabrinus coloratus), a disjunct subspecies associated with high elevation (>1385 m) forests. Using environmental parameters diagnostic of squirrel habitat, we created 35 a priori occupancy models in the program PRESENCE for boxes surveyed in western North Carolina, 1996-2011. Our best approximating model showed CNFS denning associated with sheltered landforms and montane conifers, primarily red spruce Picea rubens. As sheltering decreased, decreasing distance to conifers was important. Area with a high probability (>0.5) of occupancy was distributed over 18662 ha of habitat, mostly across 10 mountain ranges. Because nest-box surveys underrepresented areas >1750 m and CNFS forage in conifers, we combined areas of high occupancy with conifer GIS coverages to create an additional distribution model of likely habitat. Regionally, above 1385 m, we determined that 31795 ha could be occupied by CNFS. Known occupied patches ranged from

  13. Complete mitochondrial genome of the Eurasian flying squirrel Pteromys volans (Sciuromorpha, Sciuridae) and revision of rodent phylogeny.

    Science.gov (United States)

    Ryu, Shi Hyun; Kwak, Min Jung; Hwang, Ui Wook

    2013-02-01

    In this study, the complete mitochondrial genome of the Eurasian flying squirrel Pteromys volans (Rodentia, Sciuromorpha, Sciuridae) was sequenced and characterized in detail. The entire mitochondrial genome of P. volans consisted of 16,513 bp and contained 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and two non-coding regions. Its gene arrangement pattern was consistent with the mammalian ground pattern. The overall base composition and AT contents were similar to those of other rodent mitochondrial genomes. The light-strand origin generally identified between tRNA ( Asn ) and tRNA ( Cys ) consisted of a secondary structure with an 11-bp stem and an 11-bp loop. The large control region was constructed of three characteristic domains, ETAS, CD, and CSB without any repeat sequences. Each domain contained ETAS1, subsequences A, B, and C, and CSB1, respectively. In order to examine phylogenetic contentious issues of the monophyly of rodents and phylogenetic relationships among five rodent suborders, here, phylogenetic analyses based on nucleotide sequence data of the 35 rodent and 3 lagomorph mitochondrial genomes were performed using the Bayesian inference and maximum likelihood method. The result strongly supported the rodent monophyly with high node confidence values (BP 100 % in ML and BPP 1.00 in BI) and also monophylies of four rodent suborders (BP 85-100 % in ML and BPP 1.00 in BI), except for Anomalumorpha in which only one species was examined here. Also, phylogenetic relationships among the five rodent suborders were suggested and discussed in detail.

  14. Environ: E00272 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available Urate [CPD:C00366] Trogopterus xanthipes [TAX:226819], Pteromys volans [TAX:55152] Petaurista flying squirrel feces Crude drugs [BR:br08305] Animals Mammals E00272 Trogopterus feces ...

  15. Scaling of the mandible in squirrels.

    Science.gov (United States)

    Velhagen, W A; Roth, V L

    1997-05-01

    We compared the shape of the mandible among New World tree squirrels and selected outgroup taxa using linear measurements and areas defined by the median axis and conventional anatomical landmarks. We modified the median axis technique to define novel measurements, which proved complementary to those obtained from conventional landmarks. Allometric analyses showed that the scaling of the mandible among the New World tree squirrels is generally isometric (as has been observed in other groups of mammals), but diverges from isometry in a tendency in smaller animals for the masseteric ridge to be displaced anteriorly, the condylar process and posterior portion of the ascending ramus to be relatively elongated, and the coronoid process to be shortened. Allometric analyses also revealed the ways and extent that outgrowth taxa deviated from the scaling pattern observed for the New World tree squirrels. A flying squirrel (subfamily Pteromyinae), a moderate-sized callosciurine squirrel, and three species of pygmy tree squirrels from Asia and Africa show mandibular proportions very similar to those predicted for New World tree squirrels of corresponding size. Ground squirrels (tribe Marmotini) and successively more distant relatives such as Aplodontia, two myomorph rodents, and a rabbit show greater differences from the New World tree squirrels in their mandibular proportions. Combining the use of median-axis and conventional measurements makes it possible to examine changing relationships between locations of anatomically homologous landmarks and the geometry of the form.

  16. Jaw muscles of New World squirrels.

    Science.gov (United States)

    Ball, S S; Roth, V L

    1995-06-01

    The jaw, suprahyoid, and extrinsic tongue muscles are described for eight species of New World squirrels, spanning more than an order of magnitude in body mass. Anatomical differences are discussed in the light of body size, natural history, and phylogeny. The relative sizes of different muscles, their orientations, and the shapes and positions of their areas of attachment vary but show few trends in relation to body size. The anatomical differences are likewise not readily explained by the mechanical requirements of the animals' diets, which are similar. The most marked anatomical differences occur in Sciurillus (the pygmy tree squirrel), as well as those genera--Glaucomys (the flying squirrel) and Tamias (the chipmunk)--that are taxonomically most distinct from the tree squirrels. Sciurillus is noteworthy for its unusually small temporalis and an anterior deep masseter that is oriented to assist in retraction of the jaw. Tamias has a more vertically oriented temporalis and greater inclination in the anterior masseter muscles than the other squirrels, features that may be associated with its large diastema and relatively posteriorly situated cheek teeth, which in turn may relate to its having cheek pouches. Our results form a valuable database of information to be used in further studies of functional morphology and phylogeny.

  17. When Squirrels Screech

    Institute of Scientific and Technical Information of China (English)

    Felipe Galindo; 李成龙

    2004-01-01

    @@ It may be that in space no one can hear you scream. But for some squirrels,that's true right here on Earth. Zoologists have discovered that a species of prairie-dwelling squirrel makes high-frequency calls that are far beyond the reach of human hearing. The squirrels use these silent screams to warn others of impending danger. While bats use ultrasound① to navigate and find prey, the squirrels'screeches appear to be the first known example of ultrasonic alarm calls in an animal.

  18. Mandible shape and dwarfism in squirrels (Mammalia, Rodentia): interaction of allometry and adaptation

    Science.gov (United States)

    Hautier, Lionel; Fabre, Pierre-Henri; Michaux, Jacques

    2009-06-01

    Squirrels include several independent lineages of dwarf forms distributed into two ecological groups: the dwarf tree and flying squirrels. The mandible of dwarf tree squirrels share a highly reduced coronoid process and a condylar process drawn backwards. Dwarf flying squirrels on the other hand, have an elongated coronoid process and a well-differentiated condylar process. To interpret such a difference, Elliptic Fourier Transform was used to evaluate how mandible shape varies with dwarfism in sciurids. The results obtained show that this clear-cut difference cannot be explained by a simple allometric relationship in relation with size decrease. We concluded that the retention of anteriorly positioned eye sockets, in relation with distance estimation, allowed the conservation of a well-differentiated coronoid process in all flying species, despite the trend towards its reduction observed among sciurids as their size decreases.

  19. Managing Rock Squirrels in Utah

    OpenAIRE

    Frey, Nicki

    2015-01-01

    Although they do not exist in large colonies like other ground squirrels, rock squirrels can still sometimes generate conflicts with homeowners and farmers alike. Most damage occurs when a few rock squirrels take residence in a homeowner’s back yard, and begin to forage on garden vegetables and fruit trees. There are several direct and indirect ways that private landowners can manage and reduce rock squirrels on their property. This fact sheet give management tips.

  20. Quadrupedal locomotor performance in two species of arboreal squirrels: predicting energy savings of gliding.

    Science.gov (United States)

    Flaherty, Elizabeth A; Ben-David, Merav; Smith, Winston P

    2010-10-01

    Gliding allows mammals to exploit canopy habitats of old-growth forests possibly as a means to save energy. To assess costs of quadrupedal locomotion for a gliding arboreal mammal, we used open-flow respirometry and a variable-speed treadmill to measure oxygen consumption and to calculate cost of transport, excess exercise oxygen consumption, and excess post-exercise oxygen consumption for nine northern flying squirrels (Glaucomys sabrinus) and four fox squirrels (Sciurus niger). Our results indicate that oxygen consumption during exercise by flying squirrels was 1.26-1.65 times higher than predicted based on body mass, and exponentially increased with velocity (from 0.84 ± 0.03 ml O(2) kg(-1) s(-1) at 0.40 m s(-1) to 1.55 ± 0.03 ml O(2) kg(-1) s(-1) at 0.67 m s(-1)). Also, cost of transport in flying squirrels increased with velocity, although excess exercise oxygen consumption and excess post-exercise oxygen consumption did not. In contrast, oxygen consumption during exercise for fox squirrels was similar to predicted, varying from 0.51 (±0.02) ml O(2) kg(-1) s(-1) at 0.63 m s(-1) to 0.54 (±0.03) ml O(2) kg(-1) s(-1) at 1.25 m s(-1). In addition, the cost of transport for fox squirrels decreased with velocity, while excess exercise oxygen consumption and excess post-exercise oxygen consumption did not. Collectively, these observations suggest that unlike fox squirrels, flying squirrels are poorly adapted to prolonged bouts of quadrupedal locomotion. The evolution of skeletal adaptations to climbing, leaping, and landing and the development of a gliding membrane likely has increased the cost of quadrupedal locomotion by >50% while resulting in energy savings during gliding and reduction in travel time between foraging patches.

  1. When Squirrels Screech

    Institute of Scientific and Technical Information of China (English)

    Felipe; Galindo; 李成龙

    2004-01-01

    松鼠(squirrel)在遇到潜在威胁时会发出尖锐刺耳的声音,研究人员最近发现,它们实际上是在使用超声波"耳语"(whisper)相互警告,而人类是听不到松鼠发出的这种声音的。这是科学家首次发现动物利用超声波作为警告的呼叫。

  2. The use of GIS and modelling approaches in squirrel population management and conservation: A review

    Science.gov (United States)

    P. W. W. Lurz; J. L. Koprowski; D. J. A. Wood

    2008-01-01

    We review modelling approaches in relation to three key areas of sciurid ecology: management, disease risk assessments and conservation. Models enable us to explore different scenarios to develop effective management and conservation strategies. They may also assist in identifying and targeting research needs for tree and flying squirrels. However, there is a need to...

  3. Native and alien squirrels in Italy

    Directory of Open Access Journals (Sweden)

    Sandro Bertolino

    2000-09-01

    Full Text Available Abstract In Italy there are four species of squirrels: the native red squirrel and other three species recently introduced. The red squirrel is present in the Italian peninsula with three subspecies, and is missing only in Salento, and Italian islands. This species is common on Alps and Apennines, while in the plains it is declining because of the habitat loss. Competition with the grey squirrel and habitat fragmentation are considered the major threats to the survival of the red squirrel. The grey squirrel is present in Piedmont and Liguria. A study on the Piedmontese colony showed that the red squirrel is disappearing from the area colonised by the grey squirrel and the damage due to bark-stripping and feeding is considerable. Free-ranging populations of the Siberian chipmunk live in Belluno, Verona, and Rome, but records of single animals were reported for other areas. The Finlayson's squirrel is present with a small nucleus in an urban area of Piedmont. Here, the impact of this species on the vegetation appears dramatic. The eradication of the grey squirrel is a priority for the conservation of the red squirrel, but control plans for the other introduced species are also needed.

  4. Bony labyrinth morphometry indicates locomotor adaptations in the squirrel-related clade (Rodentia, Mammalia)

    OpenAIRE

    2015-01-01

    The semicircular canals (SCs) of the inner ear detect angular acceleration and are located in the bony labyrinth of the petrosal bone. Based on high-resolution computed tomography, we created a size-independent database of the bony labyrinth of 50 mammalian species especially rodents of the squirrel-related clade comprising taxa with fossorial, arboreal and gliding adaptations. Our sampling also includes gliding marsupials, actively flying bats, the arboreal tree shrew and subterranean specie...

  5. Jaw muscles of Old World squirrels.

    Science.gov (United States)

    Thorington, R W; Darrow, K

    1996-11-01

    The jaw, suprahyoid, and extrinsic tongue muscles were studied in 11 genera, belonging to five tribes, of Old World squirrels. Significant variation in most of the adductor muscles is evident. The most primitive state of sciuromorphy is seen in the African tree squirrels Paraxerus and Funisciurus, especially as reflected in the anterior deep masseter. A derived state of sciuromorphy is found in five genera of Old World squirrels and perhaps evolved independently in each. Reduction of the temporalis muscle was observed in three genera, distantly related to one another. A unique arrangement of the superficial masseter is reported in the Asian giant tree squirrels, Ratufa. The arrangement of the masseter in the African pygmy squirrel, Myosciurus, is very similar to that of the South American pygmy squirrel, Sciurillus. We present hypotheses about the functional significance of these differences. In the derived state of sciuromorphy, which is found in three cases in squirrels that feed extensively on hard fruits, the anterior deep masseter is well positioned to increase the strength of the power stroke of the incisor bite. Among the pygmy squirrels, the position of the anterior deep masseter suggests that it plays a more significant role in molar chewing.

  6. Observations on the Bryant Fox Squirrel

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This published report outlines the history and current status of the Bryant Fox Squirrel in the year 1944. Topics covered in the report include Characteristics,...

  7. Delmarva Fox Squirrel Recovery Plan 1979

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The primary objective of the Recovery Plan is to restore the Delmarva fox squirrel to secure status throughout its former range, which is described in this plan. The...

  8. Delmarva Peninsula Fox Squirrel Recovery Plan 1983

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The primary objective of the Recovery Plan is to restore the Delmarva fox squirrel to secure status throughout its former range. The plan includes the following...

  9. Estimating Squirrel Abundance From Live trapping Data

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A reprint of an article from the Journal of Wildlife Management entitled "Estimating Squirrel Abundance from Live Trapping Data" by Nixon, Edwards and Eberhardt. The...

  10. Delmarva Fox Squirrel Refuge Tour Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a report by members of the Delmarva Fox Squirrel Recovery Team, the South Zone Biologist, and the Regional Forester that summarizes a tour of Chincoteague...

  11. On a new Flying Squirrel from Deli, Sumatra

    NARCIS (Netherlands)

    Jentink, F.A.

    1890-01-01

    Sciuropterus setosus, collected by Horner in the neighborhood of Padang (Sumatra) and described by Temminck in the »Fauna japonica”, seems to be such an extremely rare animal, that the type-specimen — an adult female — is the only individual hitherto observed by collectors and naturalists. Mr. Ander

  12. Delmarva Peninsula Fox Squirrel Five Year Review Summary and Evaluation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This review constitutes an evaluation of information on the Delmarva Peninsula fox squirrel that has become available since 1993, when the Delmarva Fox Squirrel...

  13. Controlling Townsend Ground Squirrels in Beaver County, Utah

    OpenAIRE

    Nelson, Mark

    2012-01-01

    Townsend ground squirrels live in colonies and construct underground burrows that have a number of entrances. The burrows may be up to 6 feet deep. The squirrels generally enter their burrows to aestivate, escaping the late summer heat

  14. Delmarva Fox Squirrel Census Report 1977 Blackwater National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Area time counts of the endangered Delmarva Peninsula Fox Squirrels and concurrently of Eastern Grey Squirrels were conducted in 1977 on several mornings during the...

  15. Tularemia without lesions in grey tree squirrels: A diagnostic challenge

    Science.gov (United States)

    Fifteen cases of Francisella tularenesis infection (tularemia) were identified in western grey (Sciurus griseus) and eastern grey (Sciurus carolinesis) squirrels submitted to the Washington Animal Disease Diagnostic Laboratory between 2008 and 2011. All of the squirrels originated in Washington stat...

  16. The major histocompatibility complex of tassel-eared squirrels. II. Genetic diversity associated with Abert squirrels.

    Science.gov (United States)

    Wettstein, P J; States, J S

    1986-01-01

    The extent of polymorphism and the rate of divergence of class I and class II sequences mapping to the mammalian major histocompatibility complex (MHC) have been the subject of experimentation and speculation. To provide further insight into the evolution of the MHC we have initiated the analysis of two geographically isolated subspecies of tassel-eared squirrels. In the preceding communication we described the number and polymorphism of TSLA class I and class II sequences in Kaibab squirrels (S. aberti kaibabensis), which live north of the Grand Canyon. In this report we present a parallel analysis of Abert squirrels (S. aberti aberti), which live south of the Grand Canyon in northern Arizona. Genomic DNA from 12 Abert squirrels was digested with restriction enzymes, electrophoresed, blotted, and hybridized with DR alpha, DR beta, DQ alpha, DQ beta, and HLA-B7 probes. The results of these hybridizations were remarkably similar to those obtained in Kaibab squirrels. The majority of class I and class II bands were identical in size and number, suggesting that Abert and Kaibab squirrels have not significantly diverged in the TSLA complex despite their geographical separation. Relative polymorphism of class II sequences was similar to that observed with Kaibab squirrels: beta sequences exhibited higher polymorphism than alpha sequences. As in Kaibab squirrels, a number of alpha and beta sequences were apparently carried on the same fragments. In comparison to class II beta sequences, there was limited polymorphism in class I sequences, although a diverse number of class I genotypes were observed. Attempts to identify segregating TSLA haplotypes were futile in that the only families of sequences with concordant distributions were DQ alpha and DQ beta. These observations and those obtained with Kaibab squirrels suggest that the present-day TSLA haplotypes of both subspecies are derived from a limited number of common, progenitor haplotypes through repeated intra

  17. A. facialis in ground squirrel (Citellus itellus

    Directory of Open Access Journals (Sweden)

    Blagojević Miloš

    2016-01-01

    Full Text Available A ground squirrel is a hibernator, which hibernation lasts, depending on the age and sex, since the end of the summer until the spring. During this period in the body of ground squirrel, as well as in other hibernators, starts lowering of all vital functions, what has been proven by numerous physiological, biochemical and histological examinations of some organ systems of this animal. The objective of our work was to investigate a part of cardiovascular system of ground squirrel so in that way to contribute to a better knowledge of this animal body structure and accordingly to comparative anatomy in general. The investigation included 6 ground squirrels, of both gender, body weight 200-300 grams. For obtaining head and neck arterial vascularization, after exsanguination of the animal, contrast mass of gelatin coloured with tempera was injected into thoracic aorta (Aorta thoracica. After injecting, the blood vessels were prepared and photographed. For obtaining the corrosive preparations of head and neck arterial blood vessels, after exsanguination of the animal, Biocryl (a mixture of liquid biocryl - methil - methacrylate monomer and biocryl in powder - methil - methacrylate polymer was injected into thoracic aorta (Aorta thoracica. After injecting the preparations were placed into 5% NaOH, for 96 hours or into 10% NaOH for 48 hours. After that they were rinsed in hot water and photographed. A. facialis in ground squirrel is an extension of A. maxillaris. The branches of A. facialis are: A. labialis inferior, A. bursae buccalis dorsalis, A. labialis superior, A. dorsalis nasi and A. angularis oculi. The obtained results regarding A. facialis in ground squirrel (Citellus citellus were compared to the same ones in rats. In rats, A. facialis is the biggest branch separating from A. carotis externa. The branches of A. facialis in rats are: Ramus glandularis, A. submentalis, A. masseterica ventralis, A. labialis inferior, A. angularis oris, A

  18. Flying Things

    DEFF Research Database (Denmark)

    Cermak, Daniel

    2016-01-01

    Daniel Cermak-Sassenrath. Flying Things. Installation. Kulturnatten 2016, Danish Science Ministry, Copenhagen, DK, Oct 14, 2016.......Daniel Cermak-Sassenrath. Flying Things. Installation. Kulturnatten 2016, Danish Science Ministry, Copenhagen, DK, Oct 14, 2016....

  19. Cup tool use by squirrel monkeys.

    Science.gov (United States)

    Buckmaster, Christine L; Hyde, Shellie A; Parker, Karen J; Lyons, David M

    2015-12-01

    Captive-born male and female squirrel monkeys spontaneously 'invented' a cup tool use technique to Contain (i.e., hold and control) food they reduced into fragments for consumption and to Contain water collected from a valve to drink. Food cup use was observed more frequently than water cup use. Observations indicate that 68% (n = 39/57) of monkeys in this population used a cup (a plastic slip cap) to Contain food, and a subset of these monkeys, 10% (n = 4/39), also used a cup to Contain water. Cup use was optional and did not replace, but supplemented, the hand/arm-to-mouth eating and direct valve drinking exhibited by all members of the population. Strategies monkeys used to bring food and cups together for food processing activity at preferred upper-level perching areas, in the arboreal-like environment in which they lived, provides evidence that monkeys may plan food processing activity with the cups. Specifically, prior to cup use monkeys obtained a cup first before food, or obtained food and a cup from the floor simultaneously, before transporting both items to upper-level perching areas. After food processing activity with cups monkeys rarely dropped the cups and more often placed the cups onto perching. Monkeys subsequently returned to use cups that they previously placed on perching after food processing activity. The latter behavior is consistent with the possibility that monkeys may keep cups at preferred perching sites for future food processing activity and merits experimental investigation. Reports of spontaneous tool use by squirrel monkeys are rare and this is the first report of population-level tool use. These findings offer insights into the cognitive abilities of squirrel monkeys and provide a new context for behavior studies with this genus and for comparative studies with other primates.

  20. Flying Scared

    DEFF Research Database (Denmark)

    Dal Sie, Marco; Josiassen, Alexander

    service quality expectations and fear of flying affect travellers' flight choices on long-haul flights. The study was set in Bangkok and primary data were obtained from a large sample of travelers departing from Suvarnabhumi Airport. While service quality emerged as a relevant factor, fear of flying didn......’t turn out as a variable affecting travellers’ choices....

  1. Delmarva Fox Squirrel Recovery Plan Second Revision 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The following recovery plan is the second revision of the Delmarva Fox Squirrel Recovery Plan and is based upon information obtained from previous planning efforts...

  2. Phylogeography of Franklin's Ground Squirrel (Spermophilus franklinii Sabine)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a research proposal to identify genetically divergent populations within the range of a species of Franklin’s ground squirrels using phylogeographic analysis.

  3. Investigations of the Delmarva Peninsula Fox Squirrel 1966

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of doing n census study of the Delmarva Peninsula Fox Squirrel is to provide some basis for determining the annual and periodic fluctuation in the...

  4. Reintroductions of the Endangered Delmarva Fox Squirrel in Maryland

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The recovery plan for Delmarva Fox Squirrel discusses the current status of the species, habitat requirements and limiting factors, recovery objectives and criteria,...

  5. Genetic Variation Within and Among Populations of Delmarva Fox Squirrels

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The objective of this study was to provide important information about genetic variation in populations of the Delmarva Fox Squirrel in the context of a more general...

  6. Delmarva Fox Squirrel Trapping Results October/November 1996

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The recovery plan for Demarva Fox Squirrel on Chesapeake Marshlands Complex discusses the current status of the species, habitat requirements and limiting factors,...

  7. Delmarva Fox Squirrel Status and Recovery Plan Update 2003

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This update has been developed to supplement the recommendations in the 1993 recovery plan for the endangered Delmarva Fox Squirrel. The conservation strategy...

  8. Bony labyrinth morphometry indicates locomotor adaptations in the squirrel-related clade (Rodentia, Mammalia).

    Science.gov (United States)

    Pfaff, Cathrin; Martin, Thomas; Ruf, Irina

    2015-06-22

    The semicircular canals (SCs) of the inner ear detect angular acceleration and are located in the bony labyrinth of the petrosal bone. Based on high-resolution computed tomography, we created a size-independent database of the bony labyrinth of 50 mammalian species especially rodents of the squirrel-related clade comprising taxa with fossorial, arboreal and gliding adaptations. Our sampling also includes gliding marsupials, actively flying bats, the arboreal tree shrew and subterranean species. The morphometric anatomy of the SCs was correlated to the locomotion mode. Even if the phylogenetic signal cannot entirely be excluded, the main significance for functional morphological studies has been found in the diameter of the SCs, whereas the radius of curvature is of minor interest. Additionally, we found clear differences in the bias angle of the canals between subterranean and gliding taxa, but also between sciurids and glirids. The sensitivity of the inner ear correlates with the locomotion mode, with a higher sensitivity of the SCs in fossorial species than in flying taxa. We conclude that the inner ear of flying and gliding mammals is less sensitive due to the large information flow into this sense organ during locomotion.

  9. Red Squirrel Facing UK Extinction Threat

    Institute of Scientific and Technical Information of China (English)

    金月勤

    2004-01-01

    "物竞天择,适者生存",达尔文的这一至理名言现在又要在英国的红松鼠身上得以证明:Fast losing ground to the imported gray squirrel,the red’snumbers have become dangerously low in its English strongholds of Cumbria andNorthumberland.读完此文,读者可能会想起一件旧事:澳大利亚政府从国外引进兔子,但由于对它们的繁殖失去了控制,导致生态危机,最后不得不全民灭兔。

  10. Amygdalar vocalization pathways in the squirrel monkey.

    Science.gov (United States)

    Jürgens, U

    1982-06-10

    In 22 squirrel monkeys (Saimiri sciureus) vocalization-eliciting electrodes were implanted into the amygdala and along the trajectory of the stria terminalis. Then, lesions were placed in the stria terminalis, its bed nucleus, the ventral amygdalofugal pathway and several di- and mesencephalic structures in order to find out the pathways along which the amygdala exerts its vocalization-controlling influence. It was found that different call types are controlled by different pathways. Purring and chattering calls, which express a self-confident, challenging attitude and an attempt to recruit fellow-combatants in intra-specific mobbing, respectively, are controlled via the stria terminalis; alarm peep and groaning calls, in contrast, which indicate flight motivation and resentment, respectively, are triggered via the ventral amygdalofugal fibre bundle. Both pathways traverse the dorsolateral and dorsomedial hypothalamus, respectively, and unite in the periaqueductal grey of the midbrain.

  11. Whitebark pine, grizzly bears, and red squirrels

    Science.gov (United States)

    Mattson, D.J.; Kendall, K.C.; Reinhart, D.P.; Tomback, D.F.; Arno, S.F.; Keane, R.E.

    2001-01-01

    Appropriately enough, much of this book is devoted to discussing management challenges and techniques. However, the impetus for action—the desire to save whitebark pine (Pinus albicaulis)—necessarily arises from the extent to which we cherish it for its beauty and its connections with other things that we value. Whitebark pine is at the hub of a fascinating web of relationships. It is the stuff of great stories (cf. Quammen 1994). One of the more interesting of these stories pertains to the dependence of certain grizzly bear (Ursus arctos horribilis) populations on its seeds, and the role that red squirrels (Tamiasciurus hudsonicus) play as an agent of transfer between tree and bear.

  12. Detection of squirrel poxvirus by nested and real-time PCR from red (Sciurus vulgaris and grey (Sciurus carolinensis squirrels

    Directory of Open Access Journals (Sweden)

    Stavisky Jenny

    2010-06-01

    Full Text Available Abstract Background Squirrel poxvirus (SQPV is highly pathogenic to red squirrels (Sciurus vulgaris, and is a significant contributing factor to the local extinction of the species in most parts of England and Wales, where infection is endemic in Eastern grey squirrel (Sciurus carolinensis populations. Although a nested PCR assay has been used successfully to study the epidemiology of SQPV, samples have a long processing time and the assay is not quantifiable. Results This project describes the design and optimization of a real-time PCR for SQPV. Comparison with the nested PCR showed the real-time assay to be more sensitive by one log and able to detect approximately 144 genome copies per mg of tissue. Conclusions The real-time PCR has been used to quantify viral genome load in tissues from diseased and apparently healthy red and grey squirrels, and suggests that the titre of virus in tissues from diseased red squirrels is considerably higher than that found even in a grey squirrel with cutaneous lesions.

  13. Mitochondrial genetic diversity of Eurasian red squirrels (Sciurus vulgaris) from Denmark

    DEFF Research Database (Denmark)

    Madsen, Corrie Lynne; Mouatt, Julia Thidamarth Vilstrup; Fernandez Garcia, Rut;

    2015-01-01

    Melanistic Eurasian red squirrels Sciurus vulgaris are commonly found on the Danish island of Funen. They are thought to represent native Danish squirrel types and are presently under threat from admixture with introduced red squirrels. In response, a conservation program was started in 2009...... that involves the translocation of melanistic squirrels from Funen to the squirrel-free island of Langeland. Using mitochondrial DNA of 101 historical and modern samples from throughout Denmark, we assess for the first time population structure and mitochondrial genetic diversity of Danish squirrels compared...... to its larger pan-Eurasian distribution. We find that Danish squirrels have low levels of genetic diversity, especially melanistic individuals. Bayesian skyline reconstructions show that Danish squirrels have most probably experienced a severe bottleneck within the last 200 years. Also, fine...

  14. Survival and Abundance of Delmarva Fox Squirrels at Blackwater National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Delmarva fox squirrel (DFS; Sciurus niger cinereus) is a subspecies of the Eastern fox squirrel. The DFS once ranged from southeastern Pennsylvania (Poole, 1932)...

  15. Macroparasites of Pallas's squirrels (Callosciurus erythraeus) introduced into Europe.

    Science.gov (United States)

    Dozières, A; Pisanu, B; Gerriet, O; Lapeyre, C; Stuyck, J; Chapuis, J-L

    2010-08-27

    Introduced pets released in natura can lead to sanitary risks for native fauna and humans. We analysed the macroparasite fauna of a total of 49 Pallas's squirrels, Callosciurus erythraeus, from two populations introduced into urbanised areas in Europe (n=16 female symbol and 13 male symbol from Antibes, France, 43 degrees 33'N-7 degrees 7'E; n=11 female symbol and 9 male symbol in from Dadizele, Belgium, 50 degrees 52'N-3 degrees 5'E). Of the 185 identified ectoparasites from Antibes, 183 were sucking lice Enderleinellus kumadai, with male squirrels 10 times more intensely infested than females. The flea Nosopsyllus fasciatus was found on two hosts. No hard ticks were recovered. Of the 131 arthropods specimens from Dadizele, 45 belonged to E. kumadai, with male squirrels three times more intensely infested than females. Eighty-six arthropods belonged to another sucking louse, Hoplopleura erismata, with males infested twice as intensely as females. No fleas or hard ticks were found. We only found 12 immature Hymenolepis sp. cestodes in the small intestine of three squirrels from Antibes and two immature Mastophorus sp. female nematodes in the stomach of a squirrel from Dadizele. We found no other helminths in the body cavity, heart, lung, liver, kidney or bladder. The macroparasite fauna of these two squirrel populations is consistent with what is expected from an introduced host, i.e., a few species dominated by specialist taxa imported with founders. The scarcity of other rodent species in the urbanized areas where Pallas's squirrels were sampled may explain the low variety of newly acquired macroparasites. The discrepancy in sucking lice infestations between males and females could be due to differences in either behaviour or physiology in this non-sexually dimorphic host. Based on the macroparasites found in this study, we expect minimal sanitary risks for both native fauna and humans in urbanized habitats such as those in our study.

  16. Time flies

    DEFF Research Database (Denmark)

    Wit, Janneke

    , the LS fly might be able to spend energy more generously on different tasks. Therefor, the capacity of LS and C lines to locate resources in a natural environment was tested. It turns out that LS flies are less likely to find food than C flies in such a setting, yet that as they age, their ability...... to locate food decreases slower than that of C lines. Gene expression of 10 candidate genes for longevity was quantified in two types of C and LS lines at three different ages. One of these genes, CG32638, indeed appears to be involved in life span determination in both males and females, regardless...... of mating status. Generalising studies on ageing in D. melanogaster can be cumbersome, especially in light of discrepancy between correlated responses between studies. To elucidate which mechanisms might be conserved due to evolutionary constraints, life span of 13 species of Drosophila was determined...

  17. The major histocompatibility complex of tassel-eared squirrels. I. Genetic diversity associated with Kaibab squirrels.

    Science.gov (United States)

    Wettstein, P J; States, J S

    1986-01-01

    The complexity and polymorphism of sequences related to the class I and class II genes of mammalian major histocompatibility complexes (MHCs) were investigated in the tassel-eared squirrel subspecies Sciurus aberti kaibabensis or Kaibab squirrel. Kaibab squirrels are geographically isolated on the Kaibab plateau north of the Grand Canyon in Arizona. Genomic DNA from 22 individuals was digested with Eco RI and Bam HI, electrophoresed, blotted, and hybridized with a panel of human class I and class II probes. Sequences homologous to DR alpha, DR beta, DQ beta probes were observed. A single, nonpolymorphic DR alpha-related sequence and multiple, polymorphic DQ alpha-related sequences were observed. Hybridization with DR beta and DQ beta probes revealed multiple, polymorphic sequences with such specificity that no bands were observed to hybridize with both probes. The level of polymorphism of beta sequences exceeded that observed with alpha sequences. Further, three Eco RI bands apparently included at least parts of both alpha and beta sequences. Hybridization of genomic blots with the HLA-B7 class I probe revealed a number of bands comparable in size range and number to other mammalian species. However, only a minor percentage of bands were observed to segregate. The inheritance of these five families of sequences appeared to be neither concordant nor random in the sample population. Based on prior conclusions in other species, these class I and class II sequences are presumed to map to the Kabib MHC, TLSA. Although DQ alpha- and DQ beta-related sequences were concordantly inherited, segregating sequences in the other families could not be assigned to identifiable, segregating haplotypes. These observations suggest that the present-day TSLA haplotypes have been derived from a limited number of progenitor haplotypes through repeated, intra-TSLA recombination.

  18. Flying Cities

    DEFF Research Database (Denmark)

    Herbelin, Bruno; Lasserre, Sebastien; Ciger, Jan

    2008-01-01

    . This cross-modal interaction not only supports our artistic messages, but also aims at providing anyone with a pleasant and stimulating feedback from her/his speech activity. As the feedback we have received when presenting Flying Cities was very positive, our objective is now to cross the bridge between art......Flying Cities is an artistic installation which generates imaginary cities from the speech of its visitors. Thanks to an original interactive process analyzing people's vocal input to create 3D graphics, a tangible correspondence between speech and visuals opens new possibilities of interaction...

  19. A new hepadnavirus endemic in arctic ground squirrels in Alaska.

    Science.gov (United States)

    Testut, P; Renard, C A; Terradillos, O; Vitvitski-Trepo, L; Tekaia, F; Degott, C; Blake, J; Boyer, B; Buendia, M A

    1996-07-01

    We present evidence for a novel member of the hepadnavirus family that is endemic in wild arctic ground squirrels (Spermophylus parryi kennicotti) in Alaska. This virus, designated arctic squirrel hepatitis virus (ASHV), was initially detected in the livers of animals bearing large hepatic nodules by nucleic acid hybridization with hepadnavirus probes and in plasma by cross-reactivity with antibodies to hepadnavirus surface and core antigens. The complete nucleotide sequence of the 3,302-bp-long ASHV genome was determined and compared with those of ground squirrel hepatitis virus (GSHV) and woodchuck hepatitis virus (WHV); all sequences were organized into four open reading frames, designated pre-C/C, pre-S/S, pol, and X. Despite roughly equivalent variability among the three rodent hepadnaviruses (around 16% base and 19% amino acid exchanges), ASHV appeared to be more closely related to GSHV than to WHV in phylogenetic analysis. Accordingly, preliminary studies of the pathology of ASHV infection suggested that ASHV may be a less efficient oncogenic agent than WHV. About one-third of aged animals maintained in captivity, including virus-infected as well as uninfected squirrels, developed large liver nodules, consisting of hepatocellular adenomas or carcinomas or nonmalignant lesions characterized by drastic microvesicular steatosis. ASHV-infected arctic ground squirrels may serve as a new model with which to analyze the contribution of hepadnavirus- and host-specific determinants to liver pathology and tumorigenesis.

  20. Responses of squirrel monkeys to their experimentally modified mobbing calls

    Science.gov (United States)

    Fichtel, Claudia; Hammerschmidt, Kurt

    2003-05-01

    Previous acoustic analyses suggested emotion-correlated changes in the acoustic structure of squirrel monkey (Saimiri sciureus) vocalizations. Specifically, calls given in aversive contexts were characterized by an upward shift in frequencies, often accompanied by an increase in amplitude. In order to test whether changes in frequencies or amplitude are indeed relevant for conspecific listeners, playback experiments were conducted in which either frequencies or amplitude of mobbing calls were modified. Latency and first orienting response were measured in playback experiments with six adult squirrel monkeys. After broadcasting yaps with increased frequencies or amplitude, squirrel monkeys showed a longer orienting response towards the speaker than after the corresponding control stimuli. Furthermore, after broadcasting yaps with decreased frequencies or amplitude, squirrel monkeys showed a shorter orienting response towards the speaker than after the corresponding manipulated calls with higher frequencies or amplitude. These results suggest that changes in frequencies or amplitude were perceived by squirrel monkeys, indicating that the relationship between call structure and the underlying affective state of the caller agreed with the listener's assessment of the calls. However, a simultaneous increase in frequencies and amplitude did not lead to an enhanced response, compared to each single parameter. Thus, from the receiver's perspective, both call parameters may mutually replace each other.

  1. New world origins for haemoparasites infecting United Kingdom grey squirrels (Sciurus carolinensis), as revealed by phylogenetic analysis of bartonella infecting squirrel populations in England and the United States.

    Science.gov (United States)

    Bown, K J; Ellis, B A; Birtles, R J; Durden, L A; Lello, J; Begon, M; Bennett, M

    2002-12-01

    Phylogenetic analyses of bartonella have suggested divergence between bartonellae that infect mammals native to the Old and New Worlds. We characterized bartonella isolated from Eastern grey squirrels (Sciurius carolinensis) in the United States and from grey and red squirrels (Sciurus vulgaris) in the United Kingdom by nucleotide sequence comparison (gltA and groEL). Isolates from grey squirrels in the United States and the United Kingdom were identical, and most similar to Bartonella vinsonii, a species associated with New World rodents. A single and novel bartonella genotype was obtained from all 12 red squirrel isolates. Although grey squirrels were first introduced into the United Kingdom over 125 years ago, they continue to be infected solely by the bartonella associated with grey squirrels native to the United States. These results illustrate that exotic species may be accompanied by the introduction and maintenance, over many generations, of their microparasites.

  2. Gunshot Wound Contamination with Squirrel Tissue: Wound Care Considerations

    Directory of Open Access Journals (Sweden)

    Porter W. Maerz

    2014-01-01

    Full Text Available While report of animal bites contaminating wounds is reported commonly, direct wound contamination with squirrel flesh has never been reported in the literature. The patient suffered an accidental self-inflicted gunshot wound that drove squirrel flesh and buck shot deep within his right buttock. This case outlines his hospital course and wound treatment. The patient was treated with ten days of broad spectrum antibiotics, extensive debridement of the wound in the operating room, and further treatment of the wound with a vacuum dressing system. While squirrel tissue and buckshot had to be removed from the wound on day six of the hospital stay, the patient remained afebrile without signs or symptoms of systemic illness.

  3. Equivalence Between Squirrel Cage and Sheet Rotor Induction Motor

    Science.gov (United States)

    Dwivedi, Ankita; Singh, S. K.; Srivastava, R. K.

    2016-06-01

    Due to topological changes in dual stator induction motor and high cost of its fabrication, it is convenient to replace the squirrel cage rotor with a composite sheet rotor. For an experimental machine, the inner and outer stator stampings are normally available whereas the procurement of rotor stampings is quite cumbersome and is not always cost effective. In this paper, the equivalence between sheet/solid rotor induction motor and squirrel cage induction motor has been investigated using layer theory of electrical machines, so as to enable one to utilize sheet/solid rotor in dual port experimental machines.

  4. Flying Cities

    DEFF Research Database (Denmark)

    Ciger, Jan

    2006-01-01

    The Flying Cities artistic installation brings to life imaginary cities made from the speech input of visitors. In this article we describe the original interactive process generating real time 3D graphics from spectators' vocal inputs. This example of cross-modal interaction has the nice property...... of providing a tangible correspondence between the two spaces. This interaction mean has proved to suit the artistic expression well but it also aims at providing anyone with a pleasant and stimulating feedback from speech activity, a new medium for creativity and a way to visually perceive a vocal performance....... As the feedback we have received when presenting Flying Cities was very positive, our objective now is to cross the bridge between art and the potential applications to the rehabilitation of people with reduced mobility or for the treatment of language impairments....

  5. List of the specimens of Squirrels in the Leyden Museum

    NARCIS (Netherlands)

    Jentink, F.A.

    1883-01-01

    The profound and extensive studies upon the American Squirrels by Allen 1) and Alston 2), have made this group, we must confess it, one of the best known among the Mammals. At the same time however the named authors have shown that it is almost an impossibility to give a good and exact diagnosis of

  6. A new Squirrel from the Stanley-falls

    NARCIS (Netherlands)

    Jentink, F.A.

    1906-01-01

    This beautiful greenish tinged Squirrel has been procured by Mr. G. J. A. Pool at the Stanley-falls, Congostate, in August 1905; Professor Dr. A. A. W. Hubrecht (Utrecht) had the kindness as to present it to our National Museum. It apparently is an animal belonging to a hitherto undescribed species;

  7. Polioencephalomalacia secondary to hypernatremia in squirrel monkeys (Saimiri sciureus).

    Science.gov (United States)

    Macri, S M Cummings; Masek-Hammerman, K; Crowell, A M; Fenn, M S; Knight, H L; Westmoreland, S V; Miller, A D

    2014-05-01

    Squirrel monkeys (Saimiri spp) are one of the most consistently used New World primates in biomedical research and are increasingly being used in neuroscience research, including models of drug abuse and addiction. Spontaneous neurologic disease in the squirrel monkey is uncommonly reported but includes various infectious diseases as well as cerebral amyloidosis. Hypernatremia is an extremely serious condition of hyperosmolarity that occurs as a result of water loss, adipsia, or excess sodium intake. Neurologic effects of hypernatremia reflect the cellular dehydration produced by the shift of water from the intracellular fluid space into the hypertonic extracellular fluid space. Severe hypernatremia may result in cerebrocortical laminar necrosis (polioencephalomalacia) in human patients as well as in a number of domestic species, including pigs, poultry, and ruminants. We report the clinical, histopathologic, and immunohistochemical findings of polioencephalomalacia in 13 squirrel monkeys. Polioencephalomalacia in these animals was associated with hypernatremia that was confirmed by serum levels of sodium greater than 180 mmol/L (reference range, 134.0-154.0 mmol/L [mEq/L]). All animals had concurrent diseases or experimental manipulation that predisposed to adipsia. Immunohistochemical investigation using antibodies to neuronal nuclei (NeuN), CNPase, Iba-1, and CD31 revealed necrosis of predominantly cerebral cortical layers 3, 4, and 5 characterized by neuronal degeneration and loss, oligodendrocytic loss, microglial proliferation, and vascular reactivity. The squirrel monkey is exquisitely sensitive to hyperosmolar metabolic disruption and it is associated with laminar cortical necrosis.

  8. Fire, red squirrels, whitebark pine, and Yellowstone grizzly bears

    Science.gov (United States)

    Podruzny, Shannon; Reinhart, D.P.; Mattson, David J.

    1999-01-01

    Whitebark pine (Pinus albicaulis) habitats are important to Yellowstone grizzly bears (Ursus arctos) as refugia and sources of food. Ecological relationships between whitebark pine, red squirrels (Tamiasciurus hudsonicus), and grizzly bear use of pine seeds on Mt. Washburn in Yellowstone National Park, Wyoming, were examined during 1984-86. Following large-scale fires in 1988, we repeated the study in 1995-97 to examine the effects of fire on availability of whitebark pine seed in red squirrel middens and on bear use of middens. Half of the total length of the original line transects burned. We found no red squirrel middens in burned areas. Post-fire linear-abundance (no./km) of active squirrel middens that were pooled from burned and unburned areas decreased 27% compared to pre-fire abundance, but increased in unburned portions of some habitat types. Mean size of active middens decreased 54% post-fire. Use of pine seeds by bears (linear abundance of excavated middens) in pooled burned and unburned habitats decreased by 64%, likely due to the combined effects of reduced midden availability and smaller midden size. We discourage any further large-scale losses of seed producing trees from management-prescribed fires or timber harvesting until the effects of fire on ecological relationships in the whitebark pine zone are better understood.

  9. Flying Cities

    DEFF Research Database (Denmark)

    Ciger, Jan

    2006-01-01

    of providing a tangible correspondence between the two spaces. This interaction mean has proved to suit the artistic expression well but it also aims at providing anyone with a pleasant and stimulating feedback from speech activity, a new medium for creativity and a way to visually perceive a vocal performance......The Flying Cities artistic installation brings to life imaginary cities made from the speech input of visitors. In this article we describe the original interactive process generating real time 3D graphics from spectators' vocal inputs. This example of cross-modal interaction has the nice property...

  10. Flying Fortress

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    当欧洲的年轻人想到关于德国的两种熊,一个是传统的布娃娃熊,另一个就是充满欧洲街头墙上的Teddy熊涂鸦,而这个涂鸦熊的创作者就是著名的涂鸦艺术家“Flying Fortress”,他称这些熊军队为“Teddy Tmops”。

  11. Positive reinforcement training in squirrel monkeys using clicker training.

    Science.gov (United States)

    Gillis, Timothy E; Janes, Amy C; Kaufman, Marc J

    2012-08-01

    Nonhuman primates in research environments experience regular stressors that have the potential to alter physiology and brain function, which in turn can confound some types of research studies. Operant conditioning techniques such as positive reinforcement training (PRT), which teaches animals to voluntarily perform desired behaviors, can be applied to improve behavior and reactivity. PRT has been used to train rhesus macaques, marmosets, and several other nonhuman primate species. To our knowledge, the method has yet to be used to train squirrel monkeys to perform complex tasks. Accordingly, we sought to establish whether PRT, utilizing a hand-box clicker (which emits a click sound that acts as the conditioned reinforcer), could be used to train adult male squirrel monkeys (Saimiri boliviensis, N = 14). We developed and implemented a training regimen to elicit voluntary participation in routine husbandry, animal transport, and injection procedures. Our secondary goal was to quantify the training time needed to achieve positive results. Squirrel monkeys readily learned the connection between the conditioned reinforcer (the clicker) and the positive reinforcer (food). They rapidly developed proficiency on four tasks of increasing difficulty: target touching, hand sitting, restraint training, and injection training. All subjects mastered target touching behavior within 2 weeks. Ten of 14 subjects (71%) mastered all tasks in 59.2 ± 2.6 days (range: 50-70 days). In trained subjects, it now takes about 1.25 min per monkey to weigh and administer an intramuscular injection, one-third of the time it took before training. From these data, we conclude that clicker box PRT can be successfully learned by a majority of squirrel monkeys within 2 months and that trained subjects can be managed more efficiently. These findings warrant future studies to determine whether PRT may be useful in reducing stress-induced experimental confounds in studies involving squirrel monkeys.

  12. Study of diseases of the grey squirrel (Sciurus carolinensis) in Italy. First isolation of the dermatophyte Microsporum cookei.

    Science.gov (United States)

    Caffara, M; Scagliarini, A

    1999-02-01

    The ecological risks connected with the introduction of the North American grey squirrel (Sciurus carolinensis) in Italy are many. Of particular importance is the conservation of the native red squirrel (S. vulgaris) population, since the experience from the British Isles showed that where the grey squirrel was introduced, the autochthonous red squirrel became extinct. To determine the health status of grey squirrels trapped and euthanasized during an eradication campaign in the Piedmont region, various analyses were carried out. This paper describes a preliminary mycological investigation. Microsporum cookei, a geophilic dermatophyte, was isolated for the first time from grey squirrels.

  13. Fatal Systemic Toxoplasma gondii Infection in a Red Squirrel (Sciurus vulgaris), a Swinhoe's Striped Squirrel (Tamiops swinhoei) and a New World Porcupine (Erethizontidae sp.).

    Science.gov (United States)

    Fayyad, A; Kummerfeld, M; Davina, I; Wohlsein, P; Beineke, A; Baumgärtner, W; Puff, C

    2016-01-01

    Toxoplasmosis is a parasitic disease that affects man and animals worldwide. The primary hosts and major reservoir for Toxoplasma gondii are felids and the intermediate hosts are most warm-blooded animals including man. This report describes fatal toxoplasmosis in three different rodent species in Germany: a female red squirrel (Sciurus vulgaris) and a male Swinhoe's striped squirrel (Tamiops swinhoei), both kept as pets, and a female New World porcupine (Erethizontidae sp.) from a zoo. All three animals had multifocal necrotizing hepatitis. Additional findings included lymphohistiocytic and necrotizing myocarditis in the New World porcupine and the Swinhoe's striped squirrel, lymphohistiocytic encephalomyelitis in the New World porcupine and suppurative lymphadenitis in the red squirrel. Numerous tachyzoites were identified associated with the lesions. The diagnosis was confirmed by Toxoplasma. gondii immunohistochemistry and electron microscopy. This is the first report of toxoplasmosis in a New World porcupine and a Swinhoe's striped squirrel.

  14. Rapid recovery of body mass after surgical removal of adipose tissue in ground squirrels.

    OpenAIRE

    Dark, J; Forger, N. G.; Zucker, I

    1984-01-01

    A substantial proportion of total adipose tissue mass was surgically removed from female ground squirrels during weight gain or weight loss phases of the circannual body weight cycle. Within 2 months of fat removal, squirrels had restored body mass to levels appropriate to the stage of the annual body weight cycle. These findings suggest that ground squirrels may use feedback from body lipids in controlling body weight.

  15. The hibernating 13-lined ground squirrel as a model organism for potential cold storage of platelets

    OpenAIRE

    Cooper, Scott T.; Richters, Karl E.; Melin, Travis E.; Liu, Zhi-Jian; Hordyk, Peter J.; Benrud, Ryan R.; Geiser, Lauren R.; Cash, Steve E.; Simon Shelley, C.; Howard, David R.; Ereth, Mark H.; Sola-Visner, Martha C.

    2012-01-01

    Hibernating mammals have developed many physiological adaptations to extreme environments. During hibernation, 13-lined ground squirrels (Ictidomys tridecemlineatus) must suppress hemostasis to survive prolonged body temperatures of 4–8°C and 3–5 heartbeats per minute without forming lethal clots. Upon arousal in the spring, these ground squirrels must be able to quickly restore normal clotting activity to avoid bleeding. Here we show that ground squirrel platelets stored in vivo at 4–8°C wer...

  16. The application of the European strategy on invasive alien species: an example with introduced squirrels

    OpenAIRE

    Sandro Bertolino; Piero Genovesi

    2005-01-01

    Abstract We assessed the cases of squirrel species already introduced into Italy inside the framework proposed by the European strategy on invasive alien species. We collected information on 9 introductions that originated 8 populations: 3 of grey squirrels (Sciurus carolinensis), 2 of Finlayson's squirrels (Callosciurus finlaysonii), and 3 of Siberian chip-munks (Eutamias sibiricus). Food opportunism...

  17. Effects of parasitism and morphology on squirrelpox virus seroprevalence in grey squirrels (Sciurus carolinensis.

    Directory of Open Access Journals (Sweden)

    Natasha E McGowan

    Full Text Available Invasive species have been cited as major causes of population extinctions in several animal and plant classes worldwide. The North American grey squirrel (Sciurus carolinensis has a major detrimental effect on native red squirrel (Sciurus vulgaris populations across Britain and Ireland, in part because it can be a reservoir host for the deadly squirrelpox virus (SQPV. Whilst various researchers have investigated the epizootiology of SQPV disease in grey squirrels and have modelled the consequent effects on red squirrel populations, less work has examined morphological and physiological characteristics that might make individual grey squirrels more susceptible to contracting SQPV. The current study investigated the putative relationships between morphology, parasitism, and SQPV exposure in grey squirrels. We found geographical, sex, and morphological differences in SQPV seroprevalence. In particular, larger animals, those with wide zygomatic arch widths (ZAW, males with large testes, and individuals with concurrent nematode and/or coccidial infections had an increased seroprevalence of SQPV. In addition, males with larger spleens, particularly those with narrow ZAW, were more likely to be exposed to SQPV. Overall these results show that there is variation in SQPV seroprevalence in grey squirrels and that, consequently, certain individual, or populations of, grey squirrels might be more responsible for transmitting SQPV to native red squirrel populations.

  18. Mercury and cesium-137 in urban gray squirrels

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, J.H. (Univ. of Georgia, Athens); Davis, A.H.; Bigler, W.J.; Hoff, G.L.

    1980-08-01

    Recent emphasis upon the revitalization of major cities has underscored a need for urban wildlife management. Intensive management of the wildlife populations indigenous to metropolitan areas will enhance our quality of life in many ways. One important benefit is that certain species can serve as sensitive indicators of environmental change. The gray squirrel (Sciurus carolinensis) is usually abundant in cities and they are often subject to a variety of destructive environmental factors. In an attempt to evaluate the gray squirrel as an indicator of zoonoses and pollutants, the Health Program Office of the Department of Health and Rehabilitative Services conducted a multifaceted study in Jacksonvlle, Florida during 1974. This report presents baseline measurements of body burdens of mercury and cesium-137.

  19. Hemodynamic effects of barnidipine hydrochloride in conscious squirrel monkeys.

    Science.gov (United States)

    Shibasaki, M; Inagaki, O; Takenaka, T

    1994-05-01

    1. The effects of barnidipine, a new dihydropyridine Ca2+ antagonist, on cardiovascular and renin-angiotensin-aldosterone systems were investigated in conscious squirrel monkeys. 2. Barnidipine (0.3-3 mg/kg p.o.) produced a dose-related decrease in systolic blood pressure. The hypotensive action after 3 mg/kg p.o. lasted more than 8 hr. 3. Barnidipine increased heart rate, but did not affect the PQ-interval of the electrocardiograph. 4. Barnidipine (1 and 3 mg/kg p.o.) increased plasma renin activity dose-dependently. However, it had no significant effect on plasma aldosterone concentration. 5. These results indicate that barnidipine produces a sustained hypotension without affecting atrioventricular conduction time and plasma aldosterone concentration in conscious squirrel monkeys.

  20. Spontaneous Cholelithiasis in a Squirrel Monkey (Saimiri sciureus).

    Science.gov (United States)

    Lieberman, Mia T; Wachtman, Lynn M; Marini, Robert P; Bakthavatchalu, Vasu; Fox, James G

    2016-02-01

    A mature female squirrel monkey was noted during routine semiannual examinations to have moderate progressive weight loss. Serum chemistry panels revealed marked increases in hepatic enzyme, bilirubin, and bile salt concentrations and hypoalbuminemia. Abdominal ultrasonography revealed echogenic, shadowing debris in the gallbladder, consistent with cholelithiasis. At necropsy, marked thickening and distension of the gallbladder, cystic duct, and common bile duct was noted, and more than 50 irregularly shaped, black gallstones were removed from the biliary tract. Gallbladder tissue, bile, and gallstones cultured positive for Escherichia coli and Proteus spp., suggesting a brown-pigment gallstone type secondary to a bacterial nidus. Histopathology revealed severe chronic-active diffuse cholecystitis and severe chronic-active hepatic degeneration and necrosis with severe cholestasis. To our knowledge, this report is the first description of spontaneous choleilthiasis in a squirrel monkey.

  1. Enhanced oxidative capacity of ground squirrel brain mitochondria during hibernation.

    Science.gov (United States)

    Ballinger, Mallory A; Schwartz, Christine; Andrews, Matthew T

    2017-03-01

    During hibernation, thirteen-lined ground squirrels (Ictidomys tridecemlineatus) regularly cycle between bouts of torpor and interbout arousal (IBA). Most of the brain is electrically quiescent during torpor but regains activity quickly upon arousal to IBA, resulting in extreme oscillations in energy demand during hibernation. We predicted increased functional capacity of brain mitochondria during hibernation compared with spring to accommodate the variable energy demands of hibernation. To address this hypothesis, we examined mitochondrial bioenergetics in the ground squirrel brain across three time points: spring (SP), torpor (TOR), and IBA. Respiration rates of isolated brain mitochondria through complex I of the electron transport chain were more than twofold higher in TOR and IBA than in SP (P mitochondria compared with TOR and IBA (P mitochondria function more effectively during the hibernation season, allowing for rapid production of energy to meet demand when extreme physiological changes are occurring. Copyright © 2017 the American Physiological Society.

  2. Best squirrels trade a long life for an early reproduction

    OpenAIRE

    Descamps, Sébastien; Boutin, Stan; Berteaux, Dominique; Gaillard, Jean-Michel

    2006-01-01

    Age at primiparity plays a crucial role in population dynamics and life-history evolution. Long-term data on female North American red squirrels were analysed to study the fitness consequences of delaying first reproduction. Early breeders were born earlier, had a higher breeding success and achieved a higher lifetime reproductive success than females who delayed their first reproduction, which suggests a higher quality of early breeders. However, early breeders had similar mass when tagged, ...

  3. Perception of chasing in squirrel monkeys (Saimiri sciureus).

    Science.gov (United States)

    Atsumi, Takeshi; Nagasaka, Yasuo

    2015-11-01

    Understanding the intentions of others is crucial in developing positive social relationships. Comparative human and non-human animal studies have addressed the phylogenetic origin of this ability. However, few studies have explored the importance of motion information in distinguishing others' intentions and goals in non-human primates. This study addressed whether squirrel monkeys (Saimiri sciureus) are able to perceive a goal-directed motion pattern-specifically, chasing-represented by two geometric objects. In Experiment 1, we trained squirrel monkeys to discriminate a "Chasing" sequence from a "Random" sequence. We then confirmed that this discrimination transferred to new stimuli ("Chasing" and "Random") in a probe test. To determine whether the monkeys used similarities of trajectory to discriminate chasing from random motion, we also presented a non-chasing "Clone" sequence in which the trajectories of the two figures were identical. Three of six monkeys were able to discriminate "Chasing" from the other sequences. In Experiment 2, we confirmed humans' recognition of chasing with the stimuli from Experiment 1. In Experiment 3, the three monkeys for which discrimination did not transfer to the new stimuli in Experiment 1 were trained to discriminate between "Chasing" and "Clone" sequences. At testing, all three monkeys had learned to discriminate chasing, and two transferred their learning to new stimuli. Our results suggest that squirrel monkeys use goal-directed motion patterns, rather than simply similarity of trajectory, to discriminate chasing. Further investigation is necessary to identify the motion characteristics that contribute to this discrimination.

  4. Red squirrel middens influence abundance but not diversity of other vertebrates.

    Directory of Open Access Journals (Sweden)

    Erin E Posthumus

    Full Text Available Some animals modify the environment in ways that can influence the resources available to other species. Because red squirrels (Tamiasciurus hudsonicus create large piles of conifer-cone debris (middens in which they store cones, squirrels concentrate resources that might affect biodiversity locally. To determine whether other animals are attracted to midden sites beyond their affinity for the same resources that attract red squirrels, we assessed associations between middens, mammals, and birds at population and community levels. We surveyed 75 middens where residency rates of red squirrels varied during the previous five years; sampling along this residency gradient permitted us to evaluate the influence of resources at middens beyond the influence of a resident squirrel. At each location, we quantified vegetation, landscape structure, abundance of conifer cones, and midden structure, and used capture-recapture, distance sampling, and remote cameras to quantify presence, abundance, and species richness of mammals and birds. Red squirrels and the resources they concentrated at middens influenced mammals and birds at the population scale and to a lesser extent at the community scale. At middens with higher residency rates of red squirrels, richness of medium and large mammals increased markedly and species richness of birds increased slightly. After accounting for local forest characteristics, however, only species richness of medium-to-large mammals was associated with a red squirrel being resident during surveys. In areas where red squirrels were resident during surveys or in areas with greater amounts of resources concentrated by red squirrels, abundances of two of four small mammal species and two of four bird species increased. We conclude that the presence of this ecosystem modifier and the resources it concentrates influence abundance of some mammals and birds, which may have implications for maintaining biodiversity across the wide

  5. From F = ma to flying squirrels: curricular change in an introductory physics course.

    Science.gov (United States)

    O'Shea, Brian; Terry, Laura; Benenson, Walter

    2013-06-01

    We present outcomes from curricular changes made to an introductory calculus-based physics course whose audience is primarily life sciences majors, the majority of whom plan to pursue postbaccalaureate studies in medical and scientific fields. During the 2011-2012 academic year, we implemented a Physics of the Life Sciences curriculum centered on a draft textbook that takes a novel approach to teaching physics to life sciences majors. In addition, substantial revisions were made to the homework and hands-on components of the course to emphasize the relationship between physics and the life sciences and to help the students learn to apply physical intuition to life sciences-oriented problems. Student learning and attitudinal outcomes were assessed both quantitatively, using standard physics education research instruments, and qualitatively, using student surveys and a series of postsemester interviews. Students experienced high conceptual learning gains, comparable to other active learning-based physics courses. Qualitatively, a substantial fraction of interviewed students reported an increased interest in physics relative to the beginning of the semester. Furthermore, more than half of students self-reported that they could now relate physics topics to their majors and future careers, with interviewed subjects demonstrating a high level of ability to come up with examples of how physics affects living organisms and how it helped them to better understand content presented in courses in their major.

  6. From F=ma to Flying Squirrels: Curricular Change in an Introductory Physics Course

    CERN Document Server

    O'Shea, Brian W; Benenson, Walter

    2013-01-01

    We present outcomes from curricular changes made to an introductory calculus-based physics course whose audience is primarily life science majors, the majority of whom plan to pursue post-baccalaureate studies in medical and scientific fields. During the 2011-12 academic year, we implemented a "Physics of the life sciences" curriculum centered on a draft textbook that takes a novel approach to teaching physics to life science majors. In addition, substantial revisions were made to the homework and hands-on components of the course to emphasize the relationship between physics and the life sciences and to help the students to learn to apply physical intuition to life science-oriented problems. Student learning and attitudinal outcomes were assessed both quantitatively, using standard physics education research instruments, and qualitatively, using student surveys and a series of post-semester interviews. Students experienced high conceptual learning gains, comparable to other active learning-based physics cour...

  7. Estimating Orientation of Flying Fruit Flies.

    Directory of Open Access Journals (Sweden)

    Xi En Cheng

    Full Text Available The recently growing interest in studying flight behaviours of fruit flies, Drosophila melanogaster, has highlighted the need for developing tools that acquire quantitative motion data. Despite recent advance of video tracking systems, acquiring a flying fly's orientation remains a challenge for these tools. In this paper, we present a novel method for estimating individual flying fly's orientation using image cues. Thanks to the line reconstruction algorithm in computer vision field, this work can thereby focus on the practical detail of implementation and evaluation of the orientation estimation algorithm. The orientation estimation algorithm can be incorporated into tracking algorithms. We rigorously evaluated the effectiveness and accuracy of the proposed algorithm by running experiments both on simulation data and on real-world data. This work complements methods for studying the fruit fly's flight behaviours in a three-dimensional environment.

  8. Effects of visitor numbers on captive European red squirrels (Sciurus vulgaris) and impacts on visitor experience.

    Science.gov (United States)

    Woolway, Eleanor E; Goodenough, Anne E

    2017-02-21

    Visitors to zoological collections can have substantial effects on captive animals that vary according to species, enclosure design, visitor proximity, and husbandry methods. One particularly intense form of visitor interaction occurs in immersive exhibits such as walk-through enclosures. Such enclosures are increasingly common but effects on animal behavior are currently understudied. Here, the behavior of captive European red squirrels (Sciurus vulgaris) is studied in relation to visitor numbers in a walk-through enclosure. We also quantify the correlation between squirrel encounters and visitor experience. Interaction with humans increased significantly as the number of visitors inside the enclosure increased. The number of children present significantly increased locomotion and decreased eating, possibly due to disturbance and squirrels moving away from busy areas. By contrast, the number of adults significantly increased eating and decreased inactivity due to squirrels approaching visitors. The positive reinforcement training used by the keepers (offering food rewards to the squirrels for coming to them to allow routine medical checks) meant that squirrels associated adults with food opportunities. Squirrel encounter rate (number of squirrels seen by each group of visitors) was significantly affected by the number of adults and visitor duration (positive relationships) and noise as perceived by visitors (negative relationship). Encounter rate was positively correlated with overall visitor experience. Our results indicate that visitors affect behavior but this effect is influenced by husbandry methods. It is vital that visitors, especially children, minimize noise, and move slowly in the enclosure, both for the sake of the animals and their own experience.

  9. Flying insects and Campylobacter

    DEFF Research Database (Denmark)

    Hald, Birthe; Sommer, Helle Mølgaard; Skovgård, Henrik

    Campylobacter in flies Flies of the Muscidae family forage on all kind of faeces – various fly species have different preferences. M domestica prefer pigs, horses and cattle faeces, animals which are all known to frequently excrete Campylobacter. As a result, the insects pick up pathogenic micro...... organisms, which may collect on their bodies or survive passage through the fly gut. Campylobacter and other pathogens are then easily transferred to other surfaces, for instance peoples food – or to broiler houses where they may be swallowed by chickens or contaminate the environment. On a large material...... of several species of flies collected outside broiler houses, merely ~1% of the flies were found Campylobacter positive. However, the prevalence varied considerably with fly species, time of the year, and availability of Campylobacter sources. Influx of flies to broiler houses As the influx of flies...

  10. Flying insects and Campylobacter

    DEFF Research Database (Denmark)

    Hald, Birthe; Sommer, Helle Mølgaard; Skovgård, Henrik

    to broiler houses may be counted in thousands per broiler rotation during summer periods, even a low prevalence of Campylobacter positive flies constitute a risk of introduction of Campylobacter to the chickens. M. domestica – the house fly is the most important vector fly for Campylobacter transmission...... organisms, which may collect on their bodies or survive passage through the fly gut. Campylobacter and other pathogens are then easily transferred to other surfaces, for instance peoples food – or to broiler houses where they may be swallowed by chickens or contaminate the environment. On a large material...... of several species of flies collected outside broiler houses, merely ~1% of the flies were found Campylobacter positive. However, the prevalence varied considerably with fly species, time of the year, and availability of Campylobacter sources. Influx of flies to broiler houses As the influx of flies...

  11. Seroepidemiological survey of pathogenic Yersinia in breeding squirrel monkeys in Japan.

    Science.gov (United States)

    Iwata, Taketoshi; Une, Yumi; Lee, Ken-ichi; Nakamura, Shin-ichi; Taniguchi, Takahide; Hayashidani, Hideki

    2010-08-01

    To investigate the prevalence of antibodies to pathogenic Yersinia in breeding squirrel monkeys, the serum samples of 252 squirrel monkeys from 9 zoological gardens in Japan were tested by ELISA using plasmid-encoded Yersinia outer membrane protein (Yops) as the antigen. The cutoff value was calculated by using the serum samples of the squirrel monkeys from Suriname, where no prevalence of pathogenic Yersinia have been reported. According to the cutoff value, 164 of 252 (65.1%) squirrel monkeys were considered positive against pathogenic Yersinia. These positive monkeys belonged to 8 of the 9 zoological gardens, and the percentage of the seropositive monkeys ranged from 22.2 to 89.4%. Furthermore, in one zoological garden, the positive rate of the squirrel monkeys which were over 1 year old (95.7%) was significantly higher than those which were under 1 year old (23.3%). These results suggested that pathogenic Yersinia is highly prevalent among breeding monkeys in Japan.

  12. Adenocarcinoma of the Dorsal Glands in 2 European Ground Squirrels (Spermophilus citellus)

    Science.gov (United States)

    Carminato, Antonio; Nassuato, Chiara; Vascellari, Marta; Bozzato, Elisa; Mutinelli, Franco

    2012-01-01

    Olfactory communication is an important aspect of the biology of ground squirrels; accordingly, some of their integumentary glands are associated with scent-marking behavior. Although reports of neoplasms in ground squirrels are limited, the literature on tumors in this family of rodents is extensive, with hepatocellular carcinomas in woodchucks and fibromas in squirrels being the 2 most common neoplasms. Apocrine gland tumors occur frequently in domestic animals such as cats and dogs but to our knowledge have not previously been reported in squirrels. Here we describe 2 cases of adenocarcinoma of the dorsal glands in privately owned European ground squirrels (Spermophilus citellus). The skin nodules were characterized histologically by proliferation of epithelial cells, which were arranged in a tubuloacinar pattern with neoplastic emboli within the blood vessels. Adenocarcinoma of the dorsal glands was diagnosed in light of the anatomic localization, immunohistochemistry results, and histochemistry findings. PMID:23043780

  13. Fitness implications of seasonal climate variation in Columbian ground squirrels.

    Science.gov (United States)

    Dobson, F Stephen; Lane, Jeffrey E; Low, Matthew; Murie, Jan O

    2016-08-01

    The influence of climate change on the fitness of wild populations is often studied in the context of the spring onset of the reproductive season. This focus is relevant for climate influences on reproductive success, but neglects other fitness-relevant periods (e.g., autumn preparation for overwintering). We examined variation in climate variables (temperature, rainfall, snowfall, and snowpack) across the full annual cycle of Columbian ground squirrels (Urocitellus columbianus) for 21 years. We investigated seasonal climate variables that were associated with fitness variables, climate variables that exhibited directional changes across the study period, and finally observed declines in fitness (-0.03 units/year; total decline = 37%) that were associated with directional changes in climate variables. Annual fitness of adult female ground squirrels was positively associated with spring temperature (r = 0.69) and early summer rainfall (r = 0.56) and negatively associated with spring snow conditions (r = -0.44 to -0.66). Across the 21 years, spring snowmelt has become significantly delayed (r = 0.48) and summer rainfall became significantly reduced (r = -0.53). Using a standardized partial regression model, we found that directional changes in the timing of spring snowmelt and early summer rainfall (i.e., progressively drier summers) had moderate influences on annual fitness, with the latter statistically significant (ρ = -0.314 and 0.437, respectively). The summer period corresponds to prehibernation fattening of young and adult ground squirrels. Had we focused on a single point in time (viz. the onset of the breeding season), we would have underestimated the influences of climate change on our population. Rather, we obtained a comprehensive understanding of the influences of climate change on individual fitness by investigating the full lifecycle.

  14. Stereological assessment of normal Persian squirrels (Sciurus anomalus) kidney.

    Science.gov (United States)

    Akbari, Mohsen; Goodarzi, Nader; Tavafi, Majid

    2017-03-01

    The functions of the mammalian kidney are closely related to its structure. This suggests that renal function can be completely characterized by accurate knowledge of its quantitative morphological features. The aim of this study was to investigate the histomorphometric features of the kidney using design-based and unbiased stereological methods in the Persian squirrel (Sciurus anomalus), which is the only representative of the Sciuridae family in the Middle East. The left kidneys of five animals were examined. Total volume of the kidney, cortex, and medulla were determined to be 960.75 ± 87.4, 754.31 ± 77.09 and 206.1 ± 16.89 mm(3), respectively. The glomerular number was 32844.03 ± 1069.19, and the total glomerular volume was estimated to be 36.7 ± 1.45 mm(3). The volume and length of the proximal convoluted tubule were estimated at 585.67 ± 60.7 mm(3) and 328.8 ± 14.8 m, respectively, with both values being greater than those reported in the rat kidney. The volume and length of the distal convoluted tubule were calculated at 122.34 ± 7.38 mm(3) and 234.4 ± 17.45 m, respectively, which are also greater than those reported in the rat kidney. Despite the comparable body weight, the total number and mean individual volume of glomeruli in the Persian squirrel kidney were greater than those in the rat kidney. Overall, the stereological variables of the kidneys elucidated in this study are exclusive to the Persian squirrel. Our findings, together with future renal physiological data, will contribute to a better understanding of the renal structure-function relationship in the Persian squirrel.

  15. The squirrel monkey as a candidate for space flight

    Science.gov (United States)

    Brizzee, K. R.; Ordy, J. M.; Kaack, B.

    1977-01-01

    Because of its size and other unique diurnal-primate characteristics, the squirrel monkey is used in: (1) actual bioflight missions, (2) in laboratory tests designed to clarify the risks to man during launch and recovery as well as in hazardous spaceflight environments; and (3) in the acquisition of data on unknown risks encountered in long duration space exploration. Pertinent data concerning samiri sciureus as described in published and unpublished reports are summarized. Topics include: taxonomy, ethology, life history, sensory-learning-motor capabilities in primate perspective, anatomy and physiology (including homeostatic adaptation to stress), susceptibility to environmental hazards, reproduction, care and clinical management, and previous use in aerospace biomedical research.

  16. Who's your neighbor? Acoustic cues to individual identity in red squirrel Tamiasciurus hudsonicus rattle calls

    Directory of Open Access Journals (Sweden)

    Shannon M. DIGWEED, Drew RENDALL, Teana IMBEAU

    2012-10-01

    Full Text Available North American red squirrels Tamiasciurus hudsonicus often produce a loud territorial rattle call when conspecifics enter or invade a territory. Previous playback experiments suggest that the territorial rattle call may indicate an invader's identity as squirrels responded more intensely to calls played from strangers than to calls played from neighbors. This dear-enemy effect is well known in a variety of bird and mammal species and functions to reduce aggressive interactions between known neighbors. However, although previous experiments on red squirrels suggest some form of individual differentiation and thus recognition, detailed acoustic analysis of potential acoustic cues in rattle calls have not been conducted. If calls function to aid in conspecific identification in order to mitigate aggressive territorial interactions, we would expect that individual recognition cues would be acoustically represented. Our work provides a detailed analysis of acoustic cues to identity within rattle calls. A total of 225 calls across 32 individual squirrels from Sheep River Provincial Park, Kananaskis, AB, Canada, were analyzed with discriminant function analysis for potential acoustic cues to individual identity. Initial analysis of all individuals revealed a reliable acoustic differentiation across individuals. A more detailed analysis of clusters of neighboring squirrels was performed and results again indicated a statistically significant likelihood that calls were assigned correctly to specific squirrels (55%-75% correctly assigned; in other words squirrels have distinct voices that should allow for individual identification and discrimination by conspecifics [Current Zoology 58 (5: 758–764, 2012].

  17. Macroparasite fauna of alien grey squirrels (Sciurus carolinensis: composition, variability and implications for native species.

    Directory of Open Access Journals (Sweden)

    Claudia Romeo

    Full Text Available Introduced hosts populations may benefit of an "enemy release" through impoverishment of parasite communities made of both few imported species and few acquired local ones. Moreover, closely related competing native hosts can be affected by acquiring introduced taxa (spillover and by increased transmission risk of native parasites (spillback. We determined the macroparasite fauna of invasive grey squirrels (Sciurus carolinensis in Italy to detect any diversity loss, introduction of novel parasites or acquisition of local ones, and analysed variation in parasite burdens to identify factors that may increase transmission risk for native red squirrels (S. vulgaris. Based on 277 grey squirrels sampled from 7 populations characterised by different time scales in introduction events, we identified 7 gastro-intestinal helminths and 4 parasite arthropods. Parasite richness is lower than in grey squirrel's native range and independent from introduction time lags. The most common parasites are Nearctic nematodes Strongyloides robustus (prevalence: 56.6% and Trichostrongylus calcaratus (6.5%, red squirrel flea Ceratophyllus sciurorum (26.0% and Holarctic sucking louse Neohaematopinus sciuri (17.7%. All other parasites are European or cosmopolitan species with prevalence below 5%. S. robustus abundance is positively affected by host density and body mass, C. sciurorum abundance increases with host density and varies with seasons. Overall, we show that grey squirrels in Italy may benefit of an enemy release, and both spillback and spillover processes towards native red squirrels may occur.

  18. Daily Activity and Nest Occupation Patterns of Fox Squirrels (Sciurus niger throughout the Year.

    Directory of Open Access Journals (Sweden)

    Thomas Wassmer

    Full Text Available The authors investigated the general activity and nest occupation patterns of fox squirrels in a natural setting using temperature-sensitive data loggers that measure activity as changes in the microenvironment of the animal. Data were obtained from 25 distinct preparations, upon 14 unique squirrels, totaling 1385 recording days. The animals were clearly diurnal, with a predominantly unimodal activity pattern, although individual squirrels occasionally exhibited bimodal patterns, particularly in the spring and summer. Even during the short days of winter (9 hours of light, the squirrels typically left the nest after dawn and returned before dusk, spending only about 7 hours out of the nest each day. Although the duration of the daily active phase did not change with the seasons, the squirrels exited the nest earlier in the day when the days became longer in the summer and exited the nest later in the day when the days became shorter in the winter, thus tracking dawn along the seasons. During the few hours spent outside the nest each day, fox squirrels seemed to spend most of the time sitting or lying. These findings suggest that fox squirrels may have adopted a slow life history strategy that involves long periods of rest on trees and short periods of ground activity each day.

  19. Relative roles of grey squirrels, supplementary feeding, and habitat in shaping urban bird assemblages.

    Directory of Open Access Journals (Sweden)

    Colin Bonnington

    Full Text Available Non-native species are frequently considered to influence urban assemblages. The grey squirrel Sciurus carolinensis is one such species that is widespread in the UK and is starting to spread across Europe; it predates birds' nests and can compete with birds for supplementary food. Using distance sampling across the urbanisation intensity gradient in Sheffield (UK we test whether urban grey squirrels influence avian species richness and density through nest predation and competition for supplementary food sources. We also assess how urban bird assemblages respond to supplementary feeding. We find that grey squirrels slightly reduced the abundance of breeding bird species most sensitive to squirrel nest predation by reducing the beneficial impact of woodland cover. There was no evidence that grey squirrel presence altered relationships between supplementary feeding and avian assemblage structure. This may be because, somewhat surprisingly, supplementary feeding was not associated with the richness or density of wintering bird assemblages. These associations were positive during the summer, supporting advocacy to feed birds during the breeding season and not just winter, but explanatory capacity was limited. The amount of green space and its quality, assessed as canopy cover, had a stronger influence on avian species richness and population size than the presence of grey squirrels and supplementary feeding stations. Urban bird populations are thus more likely to benefit from investment in improving the availability of high quality habitats than controlling squirrel populations or increased investment in supplementary feeding.

  20. Who's your neighbor? Acoustic cues to individual identity in red squirrel Tamiasciurus hudsonicus rattle calls

    Institute of Scientific and Technical Information of China (English)

    Shannon M.DIGWEED; Drew RENDALL; Teana IMBEAU

    2012-01-01

    North American red squirrels Tamiasciurus hudsonicus often produce a loud territorial rattle call when conspecifics enter or invade a territory.Previous playback experiments suggest that the territorial rattle call may indicate an invader's identity as squirrels responded more intensely to calls played from strangers than to calls played from neighbors.This dear-enemy effect is well known in a variety of bird and mammal species and functions to reduce aggressive interactions between known neighbors.However,although previous experiments on red squirrels suggest some form of individual differentiation and thus recognition,detailed acoustic analysis of potential acoustic cues in rattle calls have not been conducted.If calls function to aid in conspecific identification in order to mitigate aggressive territorial interactions,we would expect that individual recognition cues would be acoustically represented.Our work provides a detailed analysis of acoustic cues to identity within rattle calls.A total of 225 calls across 32 individual squirrels from Sheep River Provincial Park,Kananaskis,AB,Canada,were analyzed with discriminant function analysis for potential acoustic cues to individual identity.Initial analysis of all individuals revealed a reliable acoustic differentiation across individuals.A more detailed analysis of clusters of neighboring squirrels was performed and results again indicated a statistically significant likelihood that calls were assigned correctly to specific squirrels (55%-75% correctly assigned); in other words squirrels have distinct voices that should allow for individual identification and discrimination by conspecifics.

  1. Behavioural responses of Eastern grey squirrels, Sciurus carolinensis, to cues of risk while foraging.

    Science.gov (United States)

    Jayne, Kimberley; Lea, Stephen E G; Leaver, Lisa A

    2015-07-01

    Previous studies have shown that Eastern grey squirrels modify their behaviour while foraging to offset risks of social and predatory costs, but none have simultaneously compared whether such modifications are performed at a cost to foraging. The present study directly compares how grey squirrels respond to cues of these risks while foraging. We simulated social risk and predatory risk using acoustic playbacks of stimuli that grey squirrels might be exposed to at a foraging patch: calls of conspecifics, heterospecifics (competitor and non-competitor) and predators. We found that grey squirrels responded to predator, heterospecific competitor and conspecific playbacks by altering their foraging and vigilance behaviours. Foraging was most disrupted by increased vigilance when we played calls of predators. Squirrels' response to calls of heterospecific competitors did not differ from their response to conspecific calls, and they resumed foraging more quickly after both compared to predator calls: whereas they showed little response to calls of non-competitor heterospecifics and a white noise control. We conclude that squirrels respond differentially to calls made by conspecifics, heterospecific competitors and predators, with the most pronounced response being to calls of predators. We suggest that squirrels may view conspecific and corvid vocalisations as cues of potential conflict while foraging, necessitating increased vigilance.

  2. An Improved Method for Handling Squirrels and Similar-Size Mammals

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    McCleery, R. A.

    2007-06-01

    Full Text Available Trapping and handling animals is an important aspect of wildlife research and management. Safety precautions to minimize the risk of injuries to wildlife researchers and animal subjects are mandated by state and federal laws. Use of a modified plastic funnel aided in researcher safety in a study of fox squirrels (Sciurus niger on the Texas A&M University campus. Plastic funnels used in conjunction with canvas bags prevented animal bites or other injuries and simplified the handling and tagging of 175 fox squirrels. Studies employing the use of canvas bags with zippers for restraining squirrel-sized mammals should use the plastic funnel as an added safety precaution.

  3. Natural and anthropochorous squirrels and dormice of the Mediterranean Region

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    Marco Masseti

    2005-06-01

    Full Text Available Abstract In the Mediterranean Region, squirrels and dormice of natural and anthropochorous occurrence are today represented by 7 taxa on each. Palaeontological evidence suggests that Upper Pleistocene dispersal of the representatives of the Gliridae family seems to have occurred only on the islands of the western Mediterranean basin, whereas squirrels are not represented in insular environments. The former and present distribution of some of the extant species is discussed in the light of the human redefinition of the natural equilibrium which has been taking place since very ancient times. Riassunto Scoiattoli e ghiri a diffusione naturale ed antropocora della Regione Mediterranea Attualmente, nella Regione Mediterranea, gli scoiattoli ed i ghiri a diffusione naturale ed antropocora sono rappresentati rispettivamente da 7 taxa. Il dato paleontologico suggerisce che la distribuzione insulare dei Gliridi nel corso del Pleistocene superiore abbia interessato solo il Mediterraneo occidentale, mentre gli scoiattoli non sembrano essere stati rappresentati in nessuno degli ambienti insulari. Si discute la diffusione passata e presente di alcune delle specie attuali nell'ottica della plurimillenaria ridefinizione antropica degli equilibri naturali dell'area mediterranea.

  4. Ground squirrels use an infrared signal to deter rattlesnake predation.

    Science.gov (United States)

    Rundus, Aaron S; Owings, Donald H; Joshi, Sanjay S; Chinn, Erin; Giannini, Nicolas

    2007-09-04

    The evolution of communicative signals involves a major hurdle; signals need to effectively stimulate the sensory systems of their targets. Therefore, sensory specializations of target animals are important sources of selection on signal structure. Here we report the discovery of an animal signal that uses a previously unknown communicative modality, infrared radiation or "radiant heat," which capitalizes on the infrared sensory capabilities of the signal's target. California ground squirrels (Spermophilus beecheyi) add an infrared component to their snake-directed tail-flagging signals when confronting infrared-sensitive rattlesnakes (Crotalus oreganus), but tail flag without augmenting infrared emission when confronting infrared-insensitive gopher snakes (Pituophis melanoleucus). Experimental playbacks with a biorobotic squirrel model reveal this signal's communicative function. When the infrared component was added to the tail flagging display of the robotic models, rattlesnakes exhibited a greater shift from predatory to defensive behavior than during control trials in which tail flagging included no infrared component. These findings provide exceptionally strong support for the hypothesis that the sensory systems of signal targets should, in general, channel the evolution of signal structure. Furthermore, the discovery of previously undescribed signaling modalities such as infrared radiation should encourage us to overcome our own human-centered sensory biases and more fully examine the form and diversity of signals in the repertoires of many animal species.

  5. Mesoamerican tree squirrels evolution (Rodentia: Sciuridae): a molecular phylogenetic analysis.

    Science.gov (United States)

    Villalobos, Federico; Gutierrez-Espeleta, Gustavo

    2014-06-01

    The tribe Sciurini comprehends the genera Sciurus, Syntheosiurus, Microsciurus, Tamiasciurus and Rheinthrosciurus. The phylogenetic relationships within Sciurus have been only partially done, and the relationship between Mesoamerican species remains unsolved. The phylogenetic relationships of the Mesoamerican tree squirrels were examined using molecular data. Sequence data publicly available (12S, 16S, CYTB mitochondrial genes and IRBP nuclear gene) and cytochrome B gene sequences of four previously not sampled Mesoamerican Sciurus species were analyzed under a Bayesian multispecies coalescence model. Phylogenetic analysis of the multilocus data set showed the neotropical tree squirrels as a monophyletic clade. The genus Sciurus was paraphyletic due to the inclusion of Microsciurus species (M. alfari and M. flaviventer). The South American species S. aestuans and S. stramineus showed a sister taxa relationship. Single locus analysis based on the most compact and complete data set (i.e. CYTB gene sequences), supported the monophyly of the South American species and recovered a Mesoamerican clade including S. aureogaster, S. granatensis and S. variegatoides. These results corroborated previous findings based on cladistic analysis of cranial and post-cranial characters. Our data support a close relationship between Mesoamerican Sciurus species and a sister relationship with South American species, and corroborates previous findings in relation to the polyphyly of Microsciurus and Syntheosciurus paraphyly.

  6. Increased Na+/Ca2+ exchanger activity promotes resistance to excitotoxicity in cortical neurons of the ground squirrel (a Hibernator.

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    Juan-Juan Zhao

    Full Text Available Ground squirrel, a hibernating mammalian species, is more resistant to ischemic brain stress than rat. Gaining insight into the adaptive mechanisms of ground squirrels may help us design treatment strategies to reduce brain damage in patients suffering ischemic stroke. To understand the anti-stress mechanisms in ground squirrel neurons, we studied glutamate toxicity in primary cultured neurons of the Daurian ground squirrel (Spermophilus dauricus. At the neuronal level, for the first time, we found that ground squirrel was more resistant to glutamate excitotoxicity than rat. Mechanistically, ground squirrel neurons displayed a similar calcium influx to the rat neurons in response to glutamate or N-methyl-D-aspartate (NMDA perfusion. However, the rate of calcium removal in ground squirrel neurons was markedly faster than in rat neurons. This allows ground squirrel neurons to maintain lower level of intracellular calcium concentration ([Ca2+]i upon glutamate insult. Moreover, we found that Na+/Ca2+ exchanger (NCX activity was higher in ground squirrel neurons than in rat neurons. We also proved that overexpression of ground squirrel NCX2, rather than NCX1 or NCX3, in rat neurons promoted neuron survival against glutamate toxicity. Taken together, our results indicate that ground squirrel neurons are better at maintaining calcium homeostasis than rat neurons and this is likely achieved through the activity of ground squirrel NCX2. Our findings not only reveal an adaptive mechanism of mammalian hibernators at the cellular level, but also suggest that NCX2 of ground squirrel may have therapeutic value for suppressing brain ischemic damage.

  7. Increased Na+/Ca2+ Exchanger Activity Promotes Resistance to Excitotoxicity in Cortical Neurons of the Ground Squirrel (a Hibernator)

    Science.gov (United States)

    Zhao, Juan-Juan; Gao, Shan; Jing, Jun-Zhan; Zhu, Ming-Yue; Zhou, Chen; Chai, Zhen

    2014-01-01

    Ground squirrel, a hibernating mammalian species, is more resistant to ischemic brain stress than rat. Gaining insight into the adaptive mechanisms of ground squirrels may help us design treatment strategies to reduce brain damage in patients suffering ischemic stroke. To understand the anti-stress mechanisms in ground squirrel neurons, we studied glutamate toxicity in primary cultured neurons of the Daurian ground squirrel (Spermophilus dauricus). At the neuronal level, for the first time, we found that ground squirrel was more resistant to glutamate excitotoxicity than rat. Mechanistically, ground squirrel neurons displayed a similar calcium influx to the rat neurons in response to glutamate or N-methyl-D-aspartate (NMDA) perfusion. However, the rate of calcium removal in ground squirrel neurons was markedly faster than in rat neurons. This allows ground squirrel neurons to maintain lower level of intracellular calcium concentration ([Ca2+]i) upon glutamate insult. Moreover, we found that Na+/Ca2+ exchanger (NCX) activity was higher in ground squirrel neurons than in rat neurons. We also proved that overexpression of ground squirrel NCX2, rather than NCX1 or NCX3, in rat neurons promoted neuron survival against glutamate toxicity. Taken together, our results indicate that ground squirrel neurons are better at maintaining calcium homeostasis than rat neurons and this is likely achieved through the activity of ground squirrel NCX2. Our findings not only reveal an adaptive mechanism of mammalian hibernators at the cellular level, but also suggest that NCX2 of ground squirrel may have therapeutic value for suppressing brain ischemic damage. PMID:25415196

  8. Fly ash carbon passivation

    Science.gov (United States)

    La Count, Robert B; Baltrus, John P; Kern, Douglas G

    2013-05-14

    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 of 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.

  9. Status and conservation of the red squirrel (Sciurus vulgaris in Portugal

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    Maria da Luz Mathias

    1998-12-01

    Full Text Available Abstract The historical and recent status and distribution of the red squirrel (Sciurus vulgaris in Portugal are analysed using published data, preserved material and unpublished information. In the past the red squirrel occupied the whole of Portugal, but died out towards the end of the 16th century. Now, however, red squirrels have moved back in from Spain and recolonised forests in the north of the country. An important factor limiting the distribution of squirrels in the past was the availability of suitable habitat which provide shelter and food, such as conifer woods. Hunting pressure may also have affected numbers. In Portugal the conservation status of S. vulgaris is Rare.

  10. Red squirrels in the British Isles are infected with leprosy bacilli.

    Science.gov (United States)

    Avanzi, Charlotte; Del-Pozo, Jorge; Benjak, Andrej; Stevenson, Karen; Simpson, Victor R; Busso, Philippe; McLuckie, Joyce; Loiseau, Chloé; Lawton, Colin; Schoening, Janne; Shaw, Darren J; Piton, Jérémie; Vera-Cabrera, Lucio; Velarde-Felix, Jesùs S; McDermott, Fergal; Gordon, Stephen V; Cole, Stewart T; Meredith, Anna L

    2016-11-11

    Leprosy, caused by infection with Mycobacterium leprae or the recently discovered Mycobacterium lepromatosis, was once endemic in humans in the British Isles. Red squirrels in Great Britain (Sciurus vulgaris) have increasingly been observed with leprosy-like lesions on the head and limbs. Using genomics, histopathology, and serology, we found M. lepromatosis in squirrels from England, Ireland, and Scotland, and M. leprae in squirrels from Brownsea Island, England. Infection was detected in overtly diseased and seemingly healthy animals. Phylogenetic comparisons of British and Irish M. lepromatosis with two Mexican strains from humans show that they diverged from a common ancestor around 27,000 years ago, whereas the M. leprae strain is closest to one that circulated in Medieval England. Red squirrels are thus a reservoir for leprosy in the British Isles. Copyright © 2016, American Association for the Advancement of Science.

  11. Behavioral sleep in captive owl monkey (Aotus azarae) and squirrel monkey (Saimiri boliviensis).

    Science.gov (United States)

    Sri Kantha, Sachi; Suzuki, Juri; Hirai, Yuriko; Hirai, Hirohisa

    2009-01-01

    The objective of this study was to test the hypothesis that activity-behavioral sleep parameters differ between nocturnallyactive owl monkeys and diurnally-active squirrel monkeys which are sympatric and of Bolivian origin. The total sleep time (TST) and sleep episode length (SEL) of 7 adult owl monkey siblings and 4 adult squirrel monkeys were quantitated by actigraphy for 7 days under captive conditions. The higher TST/24 h values and longer SEL/12 h quiescent phase quantitated for owl monkeys in comparison to that of squirrel monkeys clearly indicate that the behavioral sleep is markedly different between these two groups, though they are sympatric in wild. Significant differences noted in the sleep architecture between squirrel monkeys and owl monkeys can be attributed to the influences in the selected sleep niche, threat perception from predators, and disturbances from natural elements (especially rain) in the natural habitat.

  12. Analysis of Delmarva Fox Squirrel Benchmark Population Data 1991 through 1998

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes Delmarva fox squirrel population performance between January 1991 and May 1998 on seven benchmark study sites: Blackwater National Wildlife...

  13. Final Critical Habitat for the Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis) occur based on the...

  14. Delmarva Fox Squirrel Management at Blackwater National Wildlife Refuge 1984-1994

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The recovery plan for Demarva Fox Squirrel on Chesapeake Marshlands Complex discusses the current status of the species, habitat requirements and limiting factors,...

  15. Movements, Site Fidelity and Survival of Delmarva Fox Squirrels Following Translocation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The recovery plan for squirrel on Ohio River Islands discusses the current status of the species, habitat requirements and limiting factors, recovery objectives and...

  16. Delmarva Fox Squirrel Study Blackwater National Wildlife Refuge Report #5 1991

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The recovery plan for Demarva Fox Squirrel on Chesapeake Marshlands Complex discusses the current status of the species, habitat requirements and limiting factors,...

  17. Delmarva Peninsula Fox Squirrel Study Egypt Road Block November & December 1982 March 1983

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The recovery plan for Demarva Fox Squirrel on Chesapeake Marshlands Complex discusses the current status of the species, habitat requirements and limiting factors,...

  18. Final Critical Habitat for the Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis) occur based on the...

  19. Delmarva Fox Squirrel Study Blackwater National Wildlife Refuge Report #2 1976

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The recovery plan for Demarva Fox Squirrel on Chesapeake Marshlands Complex discusses the current status of the species, habitat requirements and limiting factors,...

  20. Delmarva Fox Squirrel Study Blackwater National Wildlife Refuge Report #3 1980

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The recovery plan for Demarva Fox Squirrel on Chesapeake Marshlands Complex discusses the current status of the species, habitat requirements and limiting factors,...

  1. Ground squirrel shooting and potential lead exposure in breeding avian scavengers

    Science.gov (United States)

    Herring, Garth; Eagles-Smith, Collin A.; Wagner, Mason T.

    2016-01-01

    Recreational ground squirrel shooting is a popular activity throughout the western United States and serves as a tool for managing ground squirrel populations in agricultural regions. Belding’s ground squirrels (Spermophilus beldingi) are routinely shot in California, Nevada, and Oregon across habitats that overlap with breeding avian scavengers. Ground squirrels shot with lead (Pb)-based bullets may pose a risk to avian scavengers if they consume carcasses containing Pb fragments. To assess the potential risk to breeding avian scavengers we developed a model to estimate the number, mass, and distribution of Pb fragments in shot ground squirrels using radiographic images. Eighty percent of shot carcasses contained detectible Pb fragments with an average of 38.6 mg of Pb fragments. Seven percent of all carcasses contained Pb fragment masses exceeding a lethal dose for a model raptor nestling (e.g. American kestrel Falco sparverius). Bullet type did not influence the number of fragments in shot ground squirrels, but did influence the mass of fragments retained. Belding’s ground squirrels shot with .17 Super Mag and unknown ammunition types contained over 28 and 17 times more mass of Pb fragments than those shot with .22 solid and .22 hollow point bullets, respectively. Ground squirrel body mass was positively correlated with both the number and mass of Pb fragments in carcasses, increasing on average by 76% and 56% respectively across the range of carcass masses. Although the mass of Pb retained in ground squirrel carcasses was small relative to the original bullet mass, avian scavenger nestlings that frequently consume shot ground squirrels may be at risk for Pb-induced effects (e.g., physiology, growth, or survival). Using modeling efforts we found that if nestling golden eagles (Aquila chrysaetos), red-tailed hawks (Buteo jamaicensis), and Swainson’s hawks (B. swainsoni) consumed shot ground squirrels proportionately to the nestling’s mass, energy needs

  2. Headcount 2010: the multiplication of the grey squirrel populations introduced to Italy

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    Adriano Martinoli

    2011-02-01

    Full Text Available The introduction of non-native animal species is an important cause of loss of biodiversity, for this reason their population control has received a lot of attention in the scientific literature. While the number of introduced species of many taxa is constantly growing, the eradication of new populations (“a posteriori” action and the regulation of the trade of live animals and plants (“a priori” strategies is proceeding slowly. Tree squirrels as a taxon and grey squirrels (Sciurus carolinensis in particular are among the most successful invasive alien species. Here we present the current situation (October 2010 of the grey squirrel in Italy. The grey squirrel was first reported in Piedmont in an area around the Stupinigi forests in 1948. Subsequent major introductions were reported in Genova-Nervi (1966 and the Ticino Valley Regional Park in Lombardy (1999. In 2010, there were 24 areas with a (meta population or nucleus of grey squirrels: 23 of these were in the three regions most affected by the invasive species Piedmont, Lombardy and Liguria. The number of known areas with grey squirrel presence has strongly increased in the last years. With the exception of the Genova-Nervi population, there is a lack of detailed knowledge on grey squirrel distribution and population size in areas where animals are now known or believed to be present. We underline the necessity to introduce immediately a ban on grey squirrel trade and, preferably, to all invasive species of the Sciuridae family, and to start immediate control or eradication actions.

  3. Will Arctic ground squirrels impede or accelerate climate-induced vegetation changes to the Arctic tundra?

    Science.gov (United States)

    Dalton, J.; Flower, C. E.; Brown, J.; Gonzalez-Meler, M. A.; Whelan, C.

    2014-12-01

    Considerable attention has been given to the climate feedbacks associated with predicted vegetation shifts in the Arctic tundra in response to global environmental change. However, little is known regarding the extent to which consumers can facilitate or respond to shrub expansion. Arctic ground squirrels, the largest and most northern ground squirrel, are abundant and widespread throughout the North American tundra. Their broad diet of seeds, flowers, herbage, bird's eggs and meat speaks to the need to breed, feed, and fatten in a span of some 12-16 weeks that separate their 8-9 month bouts of hibernation with the potential consequence to impact ecosystem dynamics. Therefore Arctic ground squirrels are a good candidate to evaluate whether consumers are mere responders (bottom-up effects) or drivers (top-down) of the observed and predicted vegetation changes. As a start towards this question, we measured the foraging intensity (giving-up densities) of Arctic ground squirrels in experimental food patches within which the squirrels experience diminishing returns as they seek the raisins and peanuts that we provided at the Toolik Lake field station in northern Alaska. If the squirrels show their highest feeding intensity in the shrubs, they may impede vegetation shifts by slowing the establishment and expansion of shrubs in the tundra. Conversely, if they show their lowest feeding intensity within shrub dominated areas, they may accelerate vegetation shifts. We found neither. Feeding intensity varied most among transects and times of day, and least along a tundra-to-shrub vegetation gradient. This suggests that the impacts of squirrels will be heterogeneous - in places responders and in others drivers. We should not be surprised then to see patches of accelerated and impeded vegetation changes in the tundra ecosystem. Some of these patterns may be predictable from the foraging behavior of Arctic ground squirrels.

  4. Dissecting the mechanisms of squirrel monkey (Saimiri boliviensis) social learning.

    Science.gov (United States)

    Hopper, Lm; Holmes, An; Williams, LE; Brosnan, Sf

    2013-01-01

    Although the social learning abilities of monkeys have been well documented, this research has only focused on a few species. Furthermore, of those that also incorporated dissections of social learning mechanisms, the majority studied either capuchins (Cebus apella) or marmosets (Callithrix jacchus). To gain a broader understanding of how monkeys gain new skills, we tested squirrel monkeys (Saimiri boliviensis) which have never been studied in tests of social learning mechanisms. To determine whether S. boliviensis can socially learn, we ran "open diffusion" tests with monkeys housed in two social groups (N = 23). Over the course of 10 20-min sessions, the monkeys in each group observed a trained group member retrieving a mealworm from a bidirectional task (the "Slide-box"). Two thirds (67%) of these monkeys both learned how to operate the Slide-box and they also moved the door significantly more times in the direction modeled by the trained demonstrator than the alternative direction. To tease apart the underlying social learning mechanisms we ran a series of three control conditions with 35 squirrel monkeys that had no previous experience with the Slide-box. The first replicated the experimental open diffusion sessions but without the inclusion of a trained model, the second was a no-information control with dyads of monkeys, and the third was a 'ghost' display shown to individual monkeys. The first two controls tested for the importance of social support (mere presence effect) and the ghost display showed the affordances of the task to the monkeys. The monkeys showed a certain level of success in the group control (54% of subjects solved the task on one or more occasions) and paired controls (28% were successful) but none were successful in the ghost control. We propose that the squirrel monkeys' learning, observed in the experimental open diffusion tests, can be best described by a combination of social learning mechanisms in concert; in this case, those

  5. Dissecting the mechanisms of squirrel monkey (Saimiri boliviensis social learning

    Directory of Open Access Journals (Sweden)

    LM Hopper

    2013-02-01

    Full Text Available Although the social learning abilities of monkeys have been well documented, this research has only focused on a few species. Furthermore, of those that also incorporated dissections of social learning mechanisms, the majority studied either capuchins (Cebus apella or marmosets (Callithrix jacchus. To gain a broader understanding of how monkeys gain new skills, we tested squirrel monkeys (Saimiri boliviensis which have never been studied in tests of social learning mechanisms. To determine whether S. boliviensis can socially learn, we ran “open diffusion” tests with monkeys housed in two social groups (N = 23. Over the course of 10 20-min sessions, the monkeys in each group observed a trained group member retrieving a mealworm from a bidirectional task (the “Slide-box”. Two thirds (67% of these monkeys both learned how to operate the Slide-box and they also moved the door significantly more times in the direction modeled by the trained demonstrator than the alternative direction. To tease apart the underlying social learning mechanisms we ran a series of three control conditions with 35 squirrel monkeys that had no previous experience with the Slide-box. The first replicated the experimental open diffusion sessions but without the inclusion of a trained model, the second was a no-information control with dyads of monkeys, and the third was a ‘ghost’ display shown to individual monkeys. The first two controls tested for the importance of social support (mere presence effect and the ghost display showed the affordances of the task to the monkeys. The monkeys showed a certain level of success in the group control (54% of subjects solved the task on one or more occasions and paired controls (28% were successful but none were successful in the ghost control. We propose that the squirrel monkeys’ learning, observed in the experimental open diffusion tests, can be best described by a combination of social learning mechanisms in concert

  6. Formation Flying Concept Issues

    Directory of Open Access Journals (Sweden)

    M. V. Palkin

    2015-01-01

    Full Text Available The term “formation flying” implies coordinated movement of at least two satellites on coplanar and non-coplanar orbits with a maximum distance between them being much less than the length of the orbit. Peculiarities of formation flying concept also include:- automatic coordination of satellites;- sub-group specialization of formation flying satellites;- equipment and data exchange technology unification in each specialized group or subgroup.Formation flying satellites can be classified according to the configuration stability level (order (array, cluster («swarm», intergroup specialization rules («central satellite», «leader», «slave», manoeuvrability («active» and «passive» satellites.Tasks of formation flying include:- experiments with payload, distributed in formation flying satellites;- various near-earth space and earth-surface research;- super-sized aperture antenna development;- land-based telescope calibration;- «space advertisement» (earth-surface observable satellite compositions of a logotype, word, etc.;- orbital satellite maintenance, etc.Main issues of formation flying satellite system design are:- development of an autonomous satellite group manoeuvring technology;- providing a sufficient characteristic velocity of formation flying satellites;- ballistic and navigation maintenance for satellite formation flying;- technical and economic assessment of formation flying orbital delivery and deployment;- standardization, unification, miniaturization and integration of equipment;- intergroup and intersatellite function redistribution.

  7. Ca2+ cycling in heart cells from ground squirrels: adaptive strategies for intracellular Ca2+ homeostasis.

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    Xiao-Chen Li

    Full Text Available Heart tissues from hibernating mammals, such as ground squirrels, are able to endure hypothermia, hypoxia and other extreme insulting factors that are fatal for human and nonhibernating mammals. This study was designed to understand adaptive mechanisms involved in intracellular Ca(2+ homeostasis in cardiomyocytes from the mammalian hibernator, ground squirrel, compared to rat. Electrophysiological and confocal imaging experiments showed that the voltage-dependence of L-type Ca(2+ current (I(Ca was shifted to higher potentials in ventricular myocytes from ground squirrels vs. rats. The elevated threshold of I(Ca did not compromise the Ca(2+-induced Ca(2+ release, because a higher depolarization rate and a longer duration of action potential compensated the voltage shift of I(Ca. Both the caffeine-sensitive and caffeine-resistant components of cytosolic Ca(2+ removal were more rapid in ground squirrels. Ca(2+ sparks in ground squirrels exhibited larger amplitude/size and much lower frequency than in rats. Due to the high I(Ca threshold, low SR Ca(2+ leak and rapid cytosolic Ca(2+ clearance, heart cells from ground squirrels exhibited better capability in maintaining intracellular Ca(2+ homeostasis than those from rats and other nonhibernating mammals. These findings not only reveal adaptive mechanisms of hibernation, but also provide novel strategies against Ca(2+ overload-related heart diseases.

  8. Assessing the geographic origin of the invasive grey squirrel using DNA sequencing: Implications for management strategies

    Directory of Open Access Journals (Sweden)

    Claire D. Stevenson-Holt

    2015-01-01

    Full Text Available The invasive grey squirrel Sciurus carolinensis has become a major pest species causing negative effects to forestry and biodiversity. This study aims to assess the origin of grey squirrel within Cumbria using phylogeographic analysis to aid in management and control. The work reported analysed mitochondrial DNA sequences in the D-Loop gene of 73 grey squirrel individuals from multiple locations in the UK. The results indicate that individuals in north Cumbria are derived from individuals from Scotland and North East England. Other individuals in north Cumbria share a unique haplotype with south Cumbria and Lancashire suggesting a southerly origin and movement around or over the Cumbrian Mountain range which is thought of as a barrier to movements. The assessment of invasive species geographical origin and the identification of potential wildlife transit corridors through natural barriers are becoming more important as species shift range in response to environmental and ecological changes. With the grey squirrel population expansion also occurring in Italy, the European red squirrel may become threatened across its entire range. It is crucial to understand the population origins of the invasive grey squirrel and landscape usage to successfully manage the incursion routes and control the population.

  9. FLOTAC for diagnosis of endo-parasites in pet squirrels in southern Italy.

    Science.gov (United States)

    d'Ovidio, D; Rinaldi, L; Ianniello, D; Donnelly, T M; Pepe, P; Capasso, M; Cringoli, G

    2014-02-24

    The present study investigated the occurrence of endoparasites in pet squirrels in southern Italy. Fresh fecal samples were collected from 50 asymptomatic pet squirrels belonging to five different species (Callosciurus finlaysonii, n=6, C. prevosti, n=6; Tamias striatus, n=26, T. sibiricus, n=10; Sciurus carolinensis, n=2) housed both in pet shops and/or in private residences. All fecal samples were processed using the FLOTAC pellet technique to identify and count helminth eggs/larvae and protozoan cysts/oocysts. In addition, to detect Cryptosporidium spp. and Giardia spp. the samples were analyzed by the Remel Xpect(®) immunoassay. Helminth eggs were detected in 9 out of 50 squirrels. Specifically, eggs of Dicrocoelium dendriticum were found in 5 squirrels (C. finlaysonii, n=2; C. prevosti, n=2; T. striatus, n=1); eggs of the pinworm Syphacia spp. in 3 squirrels (C. prevosti, n=2; T. striatus, n=1); and eggs of gastrointestinal nematoda (Nippostrongylus-like) were found in 1 subject (C. prevosti). Finally, two squirrels (C. prevosti) had multiple parasitic infections with D. dendriticum and Capillaria hepatica, and with D. dendriticum and Strongyloides spp., respectively. None of the samples were positive for Cryptosporidium spp. or Giardia spp. or any other protozoa (e.g. Eimeria). To the authors' knowledge, this is the first report of a D. dendriticum natural infection in pet rodents.

  10. Competition between Eurasian red and introduced Eastern grey squirrels: the energetic significance of body-mass differences.

    OpenAIRE

    Bryce, J. M.; Speakman, J.R.; Johnson, P J; Macdonald, D W

    2001-01-01

    Daily energy expenditure (DEE) was measured in sympatric populations of red and grey squirrels using the doubly labelled water technique. Grey squirrels had significantly higher DEEs than red squirrels. However, the difference between the species was not separable from the effects of body mass on DEE. The DEEs of both species were in accordance with published allometric predictions incorporating body mass and ambient temperature. The differences in energetic requirements and social dominance,...

  11. Vocalization-correlated respiratory movements in the squirrel monkey.

    Science.gov (United States)

    Häusler, U

    2000-10-01

    Respiratory abdominal movements associated with vocalization were recorded in awake squirrel monkeys. Several call types, such as peeping, trilling, cackling, and err-chucks, were accompanied by large vocalization-correlated respiratory movements (VCRM) that started before vocalization. During purring, in contrast, only small VCRM were recorded that started later after vocal onset. VCRM during trill calls, a vocalization type with repetitive frequency modulation, showed a modulation in the rhythm of the frequency changes. A correlation with amplitude modulation was also present, but more variable. As high frequencies need a higher lung pressure for production than low frequencies, the modulation of VCRM seems to serve to optimize the lung pressure in relation to the vocalization frequency. The modulation, furthermore, may act as a mechanism to produce different trill variants. During err-chucks and staccato peeps, which show a large amplitude modulation, a nonmodulated VCRM occurred. This indicates the existence of a laryngeal amplitude-controlling mechanism that is independent from respiration.

  12. Outbreak of pasteurellosis in captive Bolivian squirrel monkeys (Saimiri boliviensis)

    Science.gov (United States)

    YOSHINO, Mizuki; SASAKI, Jun; KURAMOCHI, Konomi; IKEZAWA, Mitsutaka; MUKAIZAWA, Natsuko; GORYO, Masanobu

    2017-01-01

    In September 2012, five Bolivian squirrel monkeys housed in a zoological park died within sequential several days without obvious clinical signs. In a necrospy, one monkey presented swelling of the kidney with multifocal white nodules in the parenchyma, and other two had pulmonary congestion. Histopathologically, multifocal bacterial colonies of gram-negative coccobacillus were found in the sinusoid of the liver in all monkeys examined (Nos.1−4). Additionally, purulent pyelonephritis, pneumonia and disseminated small bacterial colonies in blood vessels were observed. Immunohistochemically, the bacterial colonies from two monkeys were positive for P. multocida capsular serotype D. Based on these findings, these monkeys were diagnosed as septicemia caused by acute P. multocida infection. PMID:28190821

  13. [Phylogeny of genus Spermophilus and position of Alashan ground squirrel (Spermophilus alashanicus, Buchner, 1888) on phylogenetic tree of Paleartic short-tailed ground squirrels].

    Science.gov (United States)

    Kapustina, S Yu; Brandler, O V; Adiya, Ya

    2015-01-01

    Phylogenetic relationships within a group of Paleartic short tailed ground squirrels (Spermophilus), recently defined as genus, are not sufficiently clear and need a critical revision. Interspecies hybridization, found in Eurasian Spermophilus, can affect the results of reconstruction of molecular phylogeny. Alashan ground squirrel position on the phylogenetic tree needs clarification. We analyzed eight nucleotide sequences of cytb gene of S. alashanicus and 127 sequences of other Spermophilus species form GenBank. S.alashanicus and S. dauricus close phylogenetic relationship, and their affinity to ancestral forms of the group are revealed. Monophyly of Colobotis subgenus was confirmed. Paraphyly of eastern and western forms of S. relictus was shown.

  14. Ever Fly a Tetrahedron?

    Science.gov (United States)

    King, Kenneth

    2004-01-01

    Few things capture the spirit of spring like flying a kite. Watching a kite dance and sail across a cloud spotted sky is not only a visually appealing experience it also provides a foundation for studies in science and mathematics. Put simply, a kite is an airfoil surface that flies when the forces of lift and thrust are greater than the forces of…

  15. A review of the competitive effects of alien grey squirrels on behaviour, activity and habitat use of red squirrels in mixed, deciduous woodland in Italy

    Directory of Open Access Journals (Sweden)

    Luc Wauters

    2005-06-01

    Full Text Available Abstract The introduction of alien species can cause competitive exclusion of ecologically similar native species when there is no niche differentiation between them. Such invasive species can constitute a serious threat to biodiversity in the region where they have been introduced, causing extinction or decline of native species through competition. A well-documented case is widescale replacement of native Eurasian red squirrel (Sciurus vulgaris by introduced eastern grey squirrel (Sciurus carolinensis on the British Isles and parts of northern Italy. Rapid increase of grey squirrel's distribution range, coincided with a dramatic decline of the native red squirrel's range, and grey squirrels have now replaced red squirrels over much of Britain and in fragmented landscapes in Piedmont, northern Italy. In this review, we consider the evidence that has been obtained from studies on competitive effects of grey squirrels on activity, habitat use, foraging behaviour and food choice of individual red squirrels in broadleaf woodlands in North-west Italy. In these habitats, there is no evidence for niche partitioning between red and grey squirrels in any of the niche parameters examined, suggesting that red squirrels are unable to adapt to avoid competition with the congener when resources become limiting. Interspecific competition seems to occur mainly for food resources that affect fitness of squirrels at crucial periods of the year, such as cached tree seeds in winter and spring. Also, the greater use of acorns by grey squirrels gives the invasive species an advantage over red squirrels in mixed deciduous woods, especially with a preponderance of oaks. This is supported by studies in Britain and Italy that show that co-existence of the two species in mixed deciduous woodlands is of short duration (e.g. less than 3-5 years with grey squirrels advantaged in resource exploitation competition, resulting in the local

  16. GENERAL ACTIVITY AND PROTECTIVE BEHAVIOUR OF THE EUROPEAN GROUND SQUIRREL (SPERMOPHILUS CITELLUS IN CAPTIVITY

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    Sandra Franova

    2013-09-01

    Full Text Available We decided to focus our research on two of the basic forms of ground squirrel s behaviour in the semi natural conditions of zoological gardens general activity and protective behavior. Our main goal was to perform a complex analysis of the ground squirrel s behaviour living in captivity and to compare the various categories of behaviour on a set timeline. We performed our research throughout the span of two years 2011 2012, during which we observed two separate ground squirrel colonies A, B. We took our compiled information and subjected these to a thorough statistical analysis and main tools of comparison. Based on a long term observation and analysis of the results, we were able to gather very detailed information about the two categories of the ground squirrel s behavior as well as the various periods on the timeline, which were worked into the ethogram of the ground squirrels living in captivity. The results from 2011 confirmed that the behavior of the ground squirrel bred in captivity both observed categories in the same way as was observed in the wild reaches two peaks with raised frequencies in manifestation of given behavior, mostly in the daily time periods, the first from 9am to 11am and the second from 2.30pm to 5pm. We also noted a change in 2012, when there was a reconstruction nearby the aviaries. These reconstructive activities influenced the behavior significant decrease of activity of the ground squirrels in the presence of the assigned workers approximately until 3pm, from which time also in connection with the lessening of the worker s presence the ground squirrels activity in their aviaries begun to rapidly rise, which held on until 5pm. The peak of protective behavior in 2012 has reached higher levels than the peak in 2011, which we attribute to their vigilance after the previous presence of people. Our results may serve as a basis for improvement of the life conditions of the ground squirrels bred in captivity as well as

  17. Rock squirrel (Spermophilus variegatus) blood sera affects proteolytic and hemolytic activities of rattlesnake venoms.

    Science.gov (United States)

    Biardi, James E; Coss, Richard G

    2011-02-01

    Rock squirrels (Spermophilus variegatus) from two sites in south central New Mexico, where prairie (Crotalus viridis viridis) and western diamondback (Crotalus atrox) rattlesnakes are common predators, were assayed for inhibition of rattlesnake venom digestive and hemostatic activities. At statistically significant levels rock squirrel blood sera reduced the metalloprotease and hemolytic activity of venoms from C. v. viridis and C. atrox more than venom from an allopatric snake species, the northern Pacific rattlesnake (Crotalus oreganus). In contrast, general proteolytic activity of venom from C. oreganus was inhibited more by S. variegatus serum defenses than activity of venom from sympatric snakes. For all three venoms, incubation with squirrel sera increased the level of fibrinolysis over venom-only treatments. These results suggest that rock squirrels (S. variegatus) can defend against metalloproteases and other proteases after envenomation from at least two of five rattlesnake predators they might encounter. However, there were statistically significant differences between general proteolytic activity and fibrinolytic activity of C. v. viridis and C. atrox venom, suggesting that rock squirrels might be differentially vulnerable to these two predators. The hypothesis that prey resistance influences snake venom evolution in a predator-prey arms race is given further support by the previously cryptic variation in venoms detected when assayed against prey defenses. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Striatal dopamine D2/3 receptor regulation by stress inoculation in squirrel monkeys

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    Alex G. Lee

    2016-06-01

    Full Text Available Intermittent mildly stressful situations provide opportunities to learn, practice, and improve coping in a process called stress inoculation. Stress inoculation also enhances cognitive control and response inhibition of impulsive motivated behavior. Cognitive control and motivation have been linked to striatal dopamine D2 and/or D3 receptors (DRD2/3 in rodents, monkeys, and humans. Here, we study squirrel monkeys randomized early in life to stress inoculation with or without maternal companionship and a no-stress control treatment condition. Striatal DRD2/3 availability in adulthood was measured in vivo by [11C]raclopride binding using positron emission tomography (PET. DRD2/3 availability was greater in caudate and putamen compared to ventral striatum as reported in PET studies of humans and other non-human primates. DRD2/3 availability in ventral striatum was also consistently greater in stress inoculated squirrel monkeys compared to no-stress controls. Squirrel monkeys exposed to stress inoculation in the presence of their mother did not differ from squirrel monkeys exposed to stress inoculation without maternal companionship. Similar effects in different social contexts extend the generality of our findings and together suggest that stress inoculation increases striatal DRD2/3 availability as a correlate of cognitive control in squirrel monkeys.

  19. The hibernating 13-lined ground squirrel as a model organism for potential cold storage of platelets.

    Science.gov (United States)

    Cooper, Scott T; Richters, Karl E; Melin, Travis E; Liu, Zhi-jian; Hordyk, Peter J; Benrud, Ryan R; Geiser, Lauren R; Cash, Steve E; Simon Shelley, C; Howard, David R; Ereth, Mark H; Sola-Visner, Martha C

    2012-05-15

    Hibernating mammals have developed many physiological adaptations to extreme environments. During hibernation, 13-lined ground squirrels (Ictidomys tridecemlineatus) must suppress hemostasis to survive prolonged body temperatures of 4-8°C and 3-5 heartbeats per minute without forming lethal clots. Upon arousal in the spring, these ground squirrels must be able to quickly restore normal clotting activity to avoid bleeding. Here we show that ground squirrel platelets stored in vivo at 4-8°C were released back into the blood within 2 h of arousal in the spring with a body temperature of 37°C but were not rapidly cleared from circulation. These released platelets were capable of forming stable clots and remained in circulation for at least 2 days before newly synthesized platelets were detected. Transfusion of autologous platelets stored at 4°C or 37°C showed the same clearance rates in ground squirrels, whereas rat platelets stored in the cold had a 140-fold increase in clearance rate. Our results demonstrate that ground squirrel platelets appear to be resistant to the platelet cold storage lesions observed in other mammals, allowing prolonged storage in cold stasis and preventing rapid clearance upon spring arousal. Elucidating these adaptations could lead to the development of methods to store human platelets in the cold, extending their shelf life.

  20. Fox squirrels match food assessment and cache effort to value and scarcity.

    Directory of Open Access Journals (Sweden)

    Mikel M Delgado

    Full Text Available Scatter hoarders must allocate time to assess items for caching, and to carry and bury each cache. Such decisions should be driven by economic variables, such as the value of the individual food items, the scarcity of these items, competition for food items and risk of pilferage by conspecifics. The fox squirrel, an obligate scatter-hoarder, assesses cacheable food items using two overt movements, head flicks and paw manipulations. These behaviors allow an examination of squirrel decision processes when storing food for winter survival. We measured wild squirrels' time allocations and frequencies of assessment and investment behaviors during periods of food scarcity (summer and abundance (fall, giving the squirrels a series of 15 items (alternating five hazelnuts and five peanuts. Assessment and investment per cache increased when resource value was higher (hazelnuts or resources were scarcer (summer, but decreased as scarcity declined (end of sessions. This is the first study to show that assessment behaviors change in response to factors that indicate daily and seasonal resource abundance, and that these factors may interact in complex ways to affect food storing decisions. Food-storing tree squirrels may be a useful and important model species to understand the complex economic decisions made under natural conditions.

  1. Flying and Your Child's Ears

    Science.gov (United States)

    ... Media Flying and Your Child's Ears KidsHealth > For Parents > Flying and Your Child's Ears Print A A A What's in this article? Flying's Effects on Ears Tips for Easing Ear Pain en español Como cuidar los oídos de su hijo(a) cuando vuele en avión Flying's Effects on ...

  2. Flying in North America

    Directory of Open Access Journals (Sweden)

    Jaromír Procházka

    2013-01-01

    Full Text Available Flying all over the world is very challenging and demanding. Although ICAO is covering every specific detail by rules, there are some personal experiences which cannot be substituted. Some of them are point out in the article.

  3. Density of red squirrels and their use of non-native tree species in the Rogów Arboretum

    Directory of Open Access Journals (Sweden)

    Krauze-Gryz Dagny

    2016-03-01

    Full Text Available The aim of the study was to compare the densities of red squirrel (Sciurus vulgaris in the arboretum and a neighbouring forest and to investigate which tree species the squirrels used. The study was conducted in the area of the Rogów Arboretum (53.76 ha and the so-called Zimna Woda and Wilczy Dół forest complexes (altogether 536 ha, all being part of an Experimental Forest Station in Rogów. The density of squirrels in the arboretum and the neighbouring forest was estimated and compared by means of snow tracks on transect routes. Changes in the abundance of squirrels throughout one year as well as their behaviour were determined on the basis of direct observations along transects running through the arboretum. More than half of the area of the arboretum was searched in order to record feeding signs of squirrels. Additionally, trees with bark stripping were recorded.

  4. The Fly Printer - Extended

    DEFF Research Database (Denmark)

    Beloff, Laura; Klaus, Malena

    2016-01-01

    Artist talk / Work-in-progress What is the purpose of a machine or an artifact, like the Fly Printer, that is dislocated, that produces images that have no meaning, no instrumentality, that depict nothing in the world? The biological and the cultural are reunited in this apparatus as a possibilit...... the results. The extended version of the Fly Printer containing the technological perception and DNNs is a collaboration between Laura Beloff and Malene Theres Klaus...

  5. Larva migrans in squirrel monkeys experimentally infected with Baylisascaris potosis.

    Science.gov (United States)

    Tokiwa, Toshihiro; Tsugo, Kosuke; Nakamura, Shohei; Taira, Kensuke; Une, Yumi

    2015-10-01

    Roundworms of the genus Baylisascaris are natural parasites primarily of wild carnivores, and they can occasionally cause infection in humans and animals. Infection results in visceral larva migrans and/or neural larva migrans, which can be severe or fatal in some animals. Recently, Baylisascaris nematodes isolated from kinkajous (Potos flavus) and previously referred to as Baylisascaris procyonis were renamed as Baylisascaris potosis; however, data regarding the pathogenicity of B. potosis towards animals and humans are lacking. In the present study, we experimentally infected squirrel monkeys (Saimiri sciureus) with B. potosis to determine the suitability of the monkey as a primate model. We used embryonated eggs of B. potosis at two different doses (10,000 eggs and 100,000 eggs) and examined the animals at 30 days post-infection. Histopathological examination showed the presence of B. potosis larvae and infiltration of inflammatory cells around a central B. potosis larvae in the brain, intestines, and liver. Nevertheless, the monkeys showed no clinical signs associated with infection. Parasitological examination revealed the presence of B. potosis larvae in the intestines, liver, lung, muscles, brain, kidney, and diaphragm. Our findings extend the range of species that are susceptible to B. potosis and provide evidence for the zoonotic potential of larva migrans in high dose infections.

  6. Immunological sex differences in socially promiscuous African ground squirrels.

    Directory of Open Access Journals (Sweden)

    Mary Beth Manjerovic

    Full Text Available Differences in how males and females respond to foreign antigens are common across taxa. Such sexual differences in the immune system are predicted to be greater in species with high promiscuity and sociality as these factors increase the likelihood of disease transmission. Intense sperm competition is thought to further this sexual dichotomy as increased investment in spermatogenesis likely incurs additional immunological costs. Xerus inauris, a ground squirrel found throughout southern Africa, is extremely social and promiscuous with one of the highest male reproductive investments among rodents. These life-history attributes suggest males and females should demonstrate a large dichotomy in immunity. Contrary to our prediction, we found no difference in spleen mass between the sexes. However, we did find significant biases in leukocyte types and red blood cell counts, possibly reflecting responses to parasite types. Among males, we predicted greater investments in spermatogenesis would result in reduced immunological investments. We found a negative association between testes and spleen size and a positive relationship between testes and number of lice suggesting trade-offs in reproductive investment possibly due to the costs associated with spermatogenesis and immunity. We suggest when measuring sexual differences in immunity it is important to consider the effects of reproductive pressures, parasite types, and life history costs.

  7. Parasite removal improves reproductive success of female North American red squirrels (Tamiasciurus hudsonicus.

    Directory of Open Access Journals (Sweden)

    Jesse E H Patterson

    Full Text Available In order to evaluate potential reproductive costs associated with parasitism, we experimentally removed ectoparasites from reproductive female North American red squirrels (Tamiasciurus hudsonicus. Body mass and overwinter survival of mothers, days to juvenile emergence, juvenile survival from birth to emergence, and body mass of juveniles at emergence were all compared to those of untreated (control animals. Ectoparasite removal did not affect the body mass of mothers throughout the lactation period and overwinter survival of mothers did not differ between treatments and controls. Likewise, there was no effect of treatment on the number of days to juvenile emergence. However, treated mothers raised offspring that were significantly heavier (11% than controls at emergence. Juveniles from treated mothers were also 24% more likely to survive from birth to emergence. Our results indicate that ectoparasites impose costs on the reproductive success of female red squirrels and that ectoparasites have the potential to influence red squirrel life-histories and population dynamics.

  8. Natural infection of the ground squirrel (Spermophilus spp. with Echinococcus granulosus in China.

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    Yu Rong Yang

    Full Text Available BACKGROUND: Echinococcus granulosus is usually transmitted between canid definitive hosts and ungulate intermediate hosts. METHODOLOGY/PRINCIPAL FINDINGS: Lesions found in the livers of ground squirrels, Spermophilus dauricus/alashanicus, trapped in Ningxia Hui Autonomous Region, an area in China co-endemic for both E. granulosus and E. multilocularis, were subjected to molecular genotyping for Echinococcus spp. DNA. One of the lesions was shown to be caused by E. granulosus and subsequently by histology to contain viable protoscoleces. CONCLUSIONS/SIGNIFICANCE: This is the first report of a natural infection of the ground squirrel with E. granulosus. This does not provide definitive proof of a cycle involving ground squirrels and dogs or foxes, but it is clear that there is active E. granulosus transmission occurring in this area, despite a recent past decline in the dog population in southern Ningxia.

  9. A brain MRI atlas of the common squirrel monkey, Saimiri sciureus

    Science.gov (United States)

    Gao, Yurui; Schilling, Kurt G.; Khare, Shweta P.; Panda, Swetasudha; Choe, Ann S.; Stepniewska, Iwona; Li, Xia; Ding, Zhoahua; Anderson, Adam; Landman, Bennett A.

    2014-03-01

    The common squirrel monkey, Saimiri sciureus, is a New World monkey with functional and microstructural organization of central nervous system similar to that of humans. It is one of the most commonly used South American primates in biomedical research. Unlike its Old World macaque cousins, no digital atlases have described the organization of the squirrel monkey brain. Here, we present a multi-modal magnetic resonance imaging (MRI) atlas constructed from the brain of an adult female squirrel monkey. In vivo MRI acquisitions include high resolution T2 structural imaging and low resolution diffusion tensor imaging. Ex vivo MRI acquisitions include high resolution T2 structural imaging and high resolution diffusion tensor imaging. Cortical regions were manually annotated on the co-registered volumes based on published histological sections.

  10. A brain MRI atlas of the common squirrel monkey, Saimiri sciureus.

    Science.gov (United States)

    Gao, Yurui; Khare, Shweta P; Panda, Swetasudha; Choe, Ann S; Stepniewska, Iwona; Li, Xia; Ding, Zhoahua; Anderson, Adam; Landman, Bennett A

    2014-03-13

    The common squirrel monkey, Saimiri sciureus, is a New World monkey with functional and microstructural organization of central nervous system similar to that of humans. It is one of the most commonly used South American primates in biomedical research. Unlike its Old World macaque cousins, no digital atlases have described the organization of the squirrel monkey brain. Here, we present a multi-modal magnetic resonance imaging (MRI) atlas constructed from the brain of an adult female squirrel monkey. In vivo MRI acquisitions include T2 structural imaging and diffusion tensor imaging. Ex vivo MRI acquisitions include T2 structural imaging and diffusion tensor imaging. Cortical regions were manually annotated on the co-registered volumes based on published histological sections.

  11. Touch screen assays of behavioural flexibility and error characteristics in Eastern grey squirrels (Sciurus carolinensis).

    Science.gov (United States)

    Chow, Pizza Ka Yee; Leaver, Lisa A; Wang, Ming; Lea, Stephen E G

    2017-01-27

    Behavioural flexibility allows animals to adjust their behaviours according to changing environmental demands. Such flexibility is frequently assessed by the discrimination-reversal learning task. We examined grey squirrels' behavioural flexibility, using a simultaneous colour discrimination-reversal learning task on a touch screen. Squirrels were trained to select their non-preferred colour in the discrimination phase, and their preferred colour was rewarded in a subsequent reversal phase. We used error rates to divide learning in each phase into three stages (perseveration, chance level and 'learned') and examined response inhibition and head-switching during each stage. We found consistent behavioural patterns were associated with each learning stage: in the perseveration stage, at the beginning of each training phase, squirrels showed comparable response latencies to correct and incorrect stimuli, along with a low level of head-switching. They quickly overcame perseveration, typically in one to three training blocks. In the chance-level stage, response latencies to both stimuli were low, but during initial discrimination squirrels showed more head-switches than in the previous stage. This suggests that squirrels were learning the current reward contingency by responding rapidly to a stimulus, but with increased attention to both stimuli. In the learned stage, response latencies to the correct stimulus and the number of head-switches were at their highest, whereas incorrect response latencies were at their lowest, and differed significantly from correct response latencies. These results suggest increased response inhibition and attention allowed the squirrels to minimise errors. They also suggest that errors in the 'learned' stage were related to impulsive emission of the pre-potent or previously learned responses.

  12. Excretory Urography by Subcutaneous Injection of Iodixanol in Persian Squirrel (Sciurus Anomalous

    Directory of Open Access Journals (Sweden)

    A. Veshkini, M. Tavana*, I. Sohrabi Haghdost1, M. Nasroulahzadeh Masouleh and S Habib Savojbolaghi

    2011-01-01

    Full Text Available There are many indications for excretory urography in humans and animals. Intravenous urography (IVU is the most practical method about other urography techniques are used because of difficulties for finding veins in IVU, due to small size of the patients. This study was performed to evaluate the feasibility of subcutaneous injection of iodixanol in providing a safe and diagnostic urogram in Persian squirrel. Twelve clinically healthy adult Persian squirrels were prepared and kept for two weeks prior to study. Blood tests were performed 7 days prior to the study. After eighteen hour fasting, animals were sedated by using xylazine/diazepam cocktail (xylazine 5mg/kg, diazepam 30mg/kg. Lateral and ventrodorsal control radiographs were taken. Thirteen hundred and 1800 mg iodine per kilogram body weight of iodixanol was injected subcutaneously over shoulder area in Persian squirrels (each dose for six Persian squirrels. Lateral and ventrodorsal radiographs were taken every 5 minutes until the pyelogram was finished. Blood tests were performed 5 days after the study. Histopathologic samples were taken from skin, kidneys, ureters and urinary bladder. The kidneys of squirrels were bean-shaped and their size was approximately 1.7×0.8 cm in ventrodorsal view for both kidneys. Subcutaneous injection of iodixanol was successful to show pyelogram, uretrogram and cystogram but it was unsuccessful in showing nephrogram without pyelogram except in one case (8.33%. Good pictures of nephrograms, calices and the ureters were obtained approximately 70 min after injection. There were no abnormal clinical signs after one week of experiment. There were no abnormal blood chemistry and hematological changes. Urinary system and skin microscopic examinations were normal. It is concluded that subcutaneous urography is an effective and reliable method for urography studies in squirrel except for nephrogram. More investigations are needed to study reasons for the lack of

  13. Macroparasite community of the Eurasian red squirrel (Sciurus vulgaris): poor species richness and diversity.

    Science.gov (United States)

    Romeo, Claudia; Pisanu, Benoît; Ferrari, Nicola; Basset, Franck; Tillon, Laurent; Wauters, Lucas A; Martinoli, Adriano; Saino, Nicola; Chapuis, Jean-Louis

    2013-10-01

    The Eurasian red squirrel (Sciurus vulgaris) is the only naturally occurring tree squirrel throughout its range. We aim at improving current knowledge on its macroparasite fauna, expecting that it will have a poor parasite diversity because in species that have no sympatric congeners parasite richness should be lower than in hosts sharing their range with several closely related species, where host-switching events and lateral transmission are promoted. We examined gastro-intestinal helminth and ectoparasite communities (excluding mites) of, respectively, 147 and 311 red squirrel roadkills collected in four biogeographic regions in Italy and France. As expected, the macroparasite fauna was poor: we found five species of nematodes and some unidentified cestodes, three fleas, two sucking lice and two hard ticks. The helminth community was dominated by a single species, the oxyurid Trypanoxyuris (Rodentoxyuris) sciuri (prevalence, 87%; mean abundance, 373 ± 65 worms/host). Its abundance varied among seasons and biogeographic regions and increased with body mass in male hosts while decreased in females. The most prevalent ectoparasites were the flea Ceratophyllus (Monopsyllus) sciurorum (28%), whose presence was affected by season, and the generalist tick Ixodes (Ixodes) ricinus that was found only in France (34%). All the other helminths and arthropod species were rare, with prevalence below 10%. However, the first record of Strongyloides robustus, a common nematode of North American Eastern grey squirrels (S. carolinensis), in two red squirrels living in areas where this alien species co-inhabits, deserves further attention, since low parasite richness could result in native red squirrels being particularly vulnerable to parasite spillover.

  14. Thermal analysis of Double Stator Switched Reluctance Machine (DSSRM with and without a squirrel cage rotor

    Directory of Open Access Journals (Sweden)

    Abbasian Mohammadali

    2017-03-01

    Full Text Available Double Stator Switched Reluctance Machine (DSSRM is a novel switched reluctance machine with limited information about its heat distribution and dissipation. This paper presents a two dimensional (2-D thermal analysis of Double Stator Switched Reluctance Machine (DSSRM to observe actual heat distribution in the parts of the machine, using Finite Element Method (FEM. Two topologies for the rotor of DSSRM are considered, Non-Squirrel Cage Double Stator Switched Reluctance Machine (NSC-DSSRM and Squirrel Cage Double Stator Switched Reluctance Machine (SC-DSSRM. The heat distribution of these two topologies is analyzed, using Computational Fluid Dynamics (CFD. Finally the results are presented and compared.

  15. Projections from the 'cingular' vocalization area in the squirrel monkey.

    Science.gov (United States)

    Müller-Preuss, P; Jürgens, U

    1976-02-13

    In 5 squirrel monkeys the anatomical projections from the 'cingular' vocalization area were studied by the autoradiographic tracing technique. The 'cingular' vocalization area lies around the sulcus cinguli at the level of the genu of the corpus callosum; its electrical stimulation yields purring and cackling calls. The following efferent connections were found: corticocortical fibers could be traced into the orbital cortex (areas 10 and 11), dorsomedial frontal cortex (areas 9, 8 and 6), limbic cortex (areas 25, 24 and 23), Broca's area (area 44), frontal operculum (area 50), insula (areas 13 and 14), and auditory association cortex (area 22). Subcortical terminal fields within the telencephalon were found in the nucleus caudatus, putamen, claustrum, globus pallidus, olfactory tubercle, preoptic region and nucleus centralis and basolateralis amygdalae. Fibers reached most of these structures along different trajectories. In the diencephalon terminal fields lay in the dorsal hypothalamus, the subthalamus, lateral habenular nucleus, and the following thalamic nuclei: nucleus reticularis, ventralis anterior, centralis medialis, centralis superior lateralis, centralis inferior, submedius, medialis dorsalis and centrum medianum. In the midbrain, the periaqueductal gray was the only projection area, extending into the parabrachial nuclei at the pontomesencephalic transition. The most caudal terminal field was found in the medial pontine gray. No terminals were detected in the nucleus ambiguus, nucleus n. hypoglossi or in any other cranial motor nucleus involved in phonation processes. A comparison of this projection system with the whole of structures producing vocalization when electrically stimulated yielded only partial overlap. Not all vocalization areas lie within the 'cingular' projection system, and inversely, not the whole projection system yielded vocalization. Overlap took place in the anterior limbic cortex, preoptic region, central amygdaloid nucleus

  16. ANALYSIS OF FLYING BIKE

    OpenAIRE

    Momin Irfan Ali Nasir Husain *1, Shah mohd. Rafique rahmatullah *2, Naumanulhaq Barkatullah Shaikh *3, Khatib Mohd. Azimuddin Najimuddin *4, Ansari Mohammad Naasir Shamsudduha *5, Ansari Mohammad Parvez Abdul Qayyum*6, Momin Mohammad Rayyan Mohammad Shakeel*7, Ansari Peer Mohammed Munna *8, Prof. Mohd. Musharraf Aamir

    2016-01-01

    Flying Bike vertical take-off and landing (VTOL) type machine which also follows Newton’s third law. It is thought of as a conventional type of aircraft with special features added to enable it to rise vertically during take-off and to land from a vertical descent.  It flies with two propellers located at front and back side. These propellers are having hovering abilities. The vehicle is controlled by tilting the propellers by using lever mechanism. Rotation is carried out by diffe...

  17. Temperature adaptation of active sodium-potassium transport and of passive permeability in erythrocytes of ground squirrels.

    Science.gov (United States)

    Kimzey, S. L.; Willis, J. S.

    1971-01-01

    Unidirectional active and passive fluxes of K-42 and Na-24 were measured in red blood cells of ground squirrels (hibernators) and guinea pigs (nonhibernators). As the temperature was lowered, ?active' (ouabain-sensitive) K influx and Na efflux were more considerably diminished in guinea pig cells than in those of ground squirrels. The fraction of total K influx which is ouabain-sensitive in red blood cells of ground squirrels was virtually constant at all temperatures, whereas it decreased abruptly in guinea pig cells as temperature was lowered.

  18. A monograph of the African Squirrels, with an enumeration of the specimens in the Leyden Museum

    NARCIS (Netherlands)

    Jentink, F.A.

    1882-01-01

    The African Squirrels have never been monographically studied, although a large number of more or less important descriptions of different species have been given, which are to be found in different periodicals. The late Temminck in his »Esquisses zoologiques sur la côte de Guiné. 1853” was the firs

  19. Conservatism and adaptability during squirrel radiation: What is mandible shape telling us?

    NARCIS (Netherlands)

    Casanovas-Vilar, I.; van Dam, Jan

    2013-01-01

    Both functional adaptation and phylogeny shape the morphology of taxa within clades. Herein we explore these two factors in an integrated way by analyzing shape and size variation in the mandible of extant squirrels using landmark-based geometric morphometrics in combination with a comparative phylo

  20. Warming up for sleep? - ground squirrels sleep during arousals from hibernation

    NARCIS (Netherlands)

    Daan, Serge; Barnes, Brian M.; Strijkstra, Arjen M.

    1991-01-01

    Hypothermia during mammalian hibernation is periodically interrupted by arousals to euthermy, the function of which is unknown. We report that arctic ground squirrels (Spermophilus parryii) consistently sleep during these arousals, and that their EEG shows the decrease in slow wave activity (δ power

  1. Seasonal variation in daily activity patterns of free-ranging European ground squirrels (Spermophilus citellus)

    NARCIS (Netherlands)

    Everts, LG; Strijkstra, AM; Hut, RA; Hoffmann, IE; Millesi, E

    2004-01-01

    Daily aboveground activity of European ground squirrels (Spermophilus citellus) in their natural habitat was recorded with a visual scanning procedure during the active seasons of 1992 and 1993. Activity patterns were analyzed with respect to time of year and to the animal's reproductive state. Abov

  2. Body weights in grey and red squirrels: do seasonal weight increases occur in conifer woodland?

    NARCIS (Netherlands)

    Lurz, P.W.W.; Lloyd, A.J.

    2000-01-01

    Seasonal body weight changes were investigated in red and grey squirrels in spruce-dominated conifer plantations in the north of England. Annual seed food availability, particularly in the spruce plantations, varies markedly and is characterized by years with large cone crops (‘mast crops’) followed

  3. WARMING UP FOR SLEEP - GROUND-SQUIRRELS SLEEP DURING AROUSALS FROM HIBERNATION

    NARCIS (Netherlands)

    DAAN, S; BARNES, BM; STRIJKSTRA, AM

    1991-01-01

    Hypothermia during mammalian hibernation is periodically interrupted by arousals to euthermy, the function of which is unknown. We report that arctic ground squirrels (Spermophilus parryii) consistently sleep during these arousals, and that their EEG shows the decrease in slow wave activity (delta-p

  4. Population dynamics of european ground squirrels (Spermophilus citellus) in a suburban area

    NARCIS (Netherlands)

    Hoffmann, IE; Millesi, E; Everts, LG; Dittami, JP

    2003-01-01

    We monitored European ground squirrels (Spermophilus citellus) in a recreation area near Vienna, Austria, over a 7-year period to follow their population dynamics. Data were obtained by mark-recapture and daily checklists in an attempt to track the fates of individuals present in a defined area. Abu

  5. Natural entrainment without dawn and dusk : The case of the European ground squirrel (Spermophilus citellus)

    NARCIS (Netherlands)

    Hut, RA; van Oort, BEH; Daan, S; Oort, Bob E.H. van

    Observational data collected in the field and in enclosures show that diurnal, burrow-dwelling European ground squirrels (Spermophilus citellus) never were above ground during twilight at dawn or at dusk. The animals emerged on average 4.02 h (SD = 0.45) after civil twilight at dawn and retreated in

  6. Natural entrainment without dawn and dusk : The case of the European ground squirrel (Spermophilus citellus)

    NARCIS (Netherlands)

    Hut, RA; van Oort, BEH; Daan, S; Oort, Bob E.H. van

    1999-01-01

    Observational data collected in the field and in enclosures show that diurnal, burrow-dwelling European ground squirrels (Spermophilus citellus) never were above ground during twilight at dawn or at dusk. The animals emerged on average 4.02 h (SD = 0.45) after civil twilight at dawn and retreated in

  7. Critical steps to ensure the successful reintroduction of the Eurasian red squirrel

    Directory of Open Access Journals (Sweden)

    Vieira, B. P

    2015-04-01

    Full Text Available Wildlife reintroduction strategies aim to establish viable long–term populations, promote conservation awareness and provide economic benefits for local communities. In Portugal, the Eurasian red squirrel (Sciurus vulgaris became extinct in the 16th century and was reintroduced in urban parks in the 1990s, mainly for aesthetic and leisure purposes. We evaluated the success of this reintroduction in two urban parks and here described the critical steps. We assessed habitat use, population density and abundance, and management steps carried out during reintroduction projects. Reintroductions have been successful to some extent given squirrels are present 20 years after release. However, populations in both parks are declining due to the lack of active management and poor quality habitat. Successful reintroduction of Eurasian red squirrel in areas without competition of alien tree squirrels involves three critical main stages. The pre–project stage includes studies on habitat quality, genetic proximity between donors and closest wild population, and health of donor stocks. In the release stage, the number of individuals released will depend on resource variability, and the hard release technique is an effective and economically viable method. Post–release activities should evaluate adaptation, mitigate mortality, monitor the need for supplementary feeding, provide veterinary support, and promote public awareness and education.

  8. Evaluation of third-party reciprocity by squirrel monkeys (Saimiri sciureus) and the question of mechanisms.

    Science.gov (United States)

    Anderson, James R; Bucher, Benoit; Kuroshima, Hika; Fujita, Kazuo

    2016-07-01

    Social evaluation during third-party interactions emerges early in human ontogeny, and it has been shown in adult capuchin monkeys who witness violations of reciprocity in object exchanges: Monkeys were less inclined to accept food from humans who refused to reciprocate with another human. A recent study reporting similar evidence in marmoset monkeys raised the possibility that such evaluations might be based on species' inherent cooperativeness. We tested a species not renowned for cooperativeness-squirrel monkeys-using the procedure used with marmosets and found a similar result. This finding rules out any crucial role for cooperative tendencies in monkeys' responses to unfair exchanges. We then tested squirrel monkeys using procedures more similar to those used in the original study with capuchins. Squirrel monkeys again accepted food less frequently from non-reciprocators, but unlike capuchins, they also strongly preferred reciprocators. We conclude that neither squirrel monkeys nor marmoset monkeys engaged in emotional bookkeeping of the type that probably underlies social evaluation in capuchin monkeys; instead, they employed one or more simple behavioral rules. Further comparative studies are required to clarify the mechanisms underlying social evaluation processes across species.

  9. Experimental Infection of Richardson's Ground Squirrels (Spermophilus richardsonii) with Attenuated and Virulent Strains of Brucella abortus

    Science.gov (United States)

    Exposure of non-target species to wildlife vaccines is an important concern when evaluating a candidate vaccine for use in the field. A previous investigation of the safety of Brucella abortus strain RB51 (sRB51) in various non-target species suggested that Richardson’s ground squirrels (Spermophil...

  10. Analysis of Efficiency Characteristics of Squirrel-Cage Induction Motor Loaded With Water System Pump

    Directory of Open Access Journals (Sweden)

    Zbigniew Lukasik

    2007-01-01

    Full Text Available The article presents a method of calculating efficiency of squirrel-cage induction motor. This efficiency depends on frequency of the voltage supplied to the motor and on electrical power. Results of laboratory testing of the motor's efficiency are presented.

  11. Acorn Caching in Tree Squirrels: Teaching Hypothesis Testing in the Park

    Science.gov (United States)

    McEuen, Amy B.; Steele, Michael A.

    2012-01-01

    We developed an exercise for a university-level ecology class that teaches hypothesis testing by examining acorn preferences and caching behavior of tree squirrels (Sciurus spp.). This exercise is easily modified to teach concepts of behavioral ecology for earlier grades, particularly high school, and provides students with a theoretical basis for…

  12. Molecular epidemiology of Bartonella species isolated from ground squirrels and other rodents in northern California.

    Science.gov (United States)

    Ziedins, A C; Chomel, B B; Kasten, R W; Kjemtrup, A M; Chang, C-C

    2016-07-01

    Bartonella spp. are endemic in wild rodents in many parts of the world. A study conducted in two northern California counties (Sonoma and Yolo) sampling California ground squirrels (Otospermophilus beecheyi) and four other rodent species (Peromyscus maniculatus, P. boylii, P. truei and Neotoma fuscipes) led to the isolation of small Gram-negative bacilli which were identified as Bartonella spp. based on colony morphology, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and partial gene sequencing. Overall, Bartonella spp. were isolated from the blood of 71% (32/45) of the ground squirrels and one third (22/66) of the other rodents. PCR-RFLP analysis of the gltA and 16S rRNA genes yielded seven unique profiles, four for the ground squirrels and three for the other rodents. Isolates from each PCR-RFLP profiles were submitted for partial sequencing. Ground squirrel isolates were most closely related to B. washoensis, whereas the other rodent isolates were closest to B. vinsonii subsp. vinsonii and B. vinsonii subsp. arupensis. Two of these three species or subspecies are known zoonotic agents.

  13. Responses of squirrel monkeys to seasonal changes in food availability in an eastern Amazonian forest.

    Science.gov (United States)

    Stone, Anita I

    2007-02-01

    Tropical forests are characterized by marked temporal and spatial variation in productivity, and many primates face foraging problems associated with seasonal shifts in fruit availability. In this study, I examined seasonal changes in diet and foraging behaviors of two groups of squirrel monkeys (Saimiri sciureus), studied for 12 months in Eastern Brazilian Amazonia, an area characterized by seasonal rainfall. Squirrel monkeys were primarily insectivorous (79% of feeding and foraging time), with fruit consumption highest during the rainy season. Although monkeys fed from 68 plant species, fruit of Attalea maripa palms accounted for 28% of annual fruit-feeding records. Dietary shifts in the dry season were correlated with a decline in ripe A. maripa fruits. Despite pronounced seasonal variation in rainfall and fruit abundance, foraging efficiency, travel time, and distance traveled remained stable between seasons. Instead, squirrel monkeys at this Eastern Amazonian site primarily dealt with the seasonal decline in fruit by showing dietary flexibility. Consumption of insects, flowers, and exudates increased during the dry season. In particular, their foraging behavior at this time strongly resembled that of tamarins (Saguinus sp.) and consisted of heavy use of seed-pod exudates and specialized foraging on large-bodied orthopterans near the forest floor. Comparisons with squirrel monkeys at other locations indicate that, across their geographic range, Saimiri use a variety of behavioral tactics during reduced periods of fruit availability.

  14. Kite-Flying Fun

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    China’s kite capital welcomes flying enthusiasts from across the world to its annual carnival Tens of thousands of kite enthusiast from all over the world gathered under the growing swarm of brightly colored kites. Some of the floating and billowing forms had been fashioned into

  15. Hydration of fly ash cement

    Energy Technology Data Exchange (ETDEWEB)

    Etsuo Sakai; Shigeyoshi Miyahara; Shigenari Ohsawa; Seung-Heun Lee; Masaki Daimon [Tokyo Institute of Technology, Tokyo (Japan). Department of Metallurgy and Ceramics Science, Graduate School of Science and Engineering

    2005-06-01

    It is necessary to establish the material design system for the utilization of large amounts of fly ash as blended cement instead of disposing of it as a waste. Cement blended with fly ash is also required as a countermeasure to reduce the amount of CO{sub 2} generation. In this study, the influences of the glass content and the basicity of glass phase on the hydration of fly ash cement were clarified and hydration over a long curing time was characterized. Two kinds of fly ash with different glass content, one with 38.2% and another with 76.6%, were used. The hydration ratio of fly ash was increased by increasing the glass content in fly ash in the specimens cured for 270 days. When the glass content of fly ash is low, the basicity of glass phase tends to decrease. Reactivity of fly ash is controlled by the basicity of the glass phase in fly ash during a period from 28 to 270 days. However, at an age of 360 days, the reaction ratios of fly ash show almost identical values with different glass contents. Fly ash also affected the hydration of cement clinker minerals in fly ash cement. While the hydration of alite was accelerated, that of belite was retarded at a late stage.

  16. Pattern of maternal circulating CRH in laboratory-housed squirrel and owl monkeys.

    Science.gov (United States)

    Power, M L; Williams, L E; Gibson, S V; Schulkin, J; Helfers, J; Zorrilla, E P

    2010-11-01

    The anthropoid primate placenta appears to be unique in producing corticotropin-releasing hormone (CRH). Placental CRH is involved in an endocrine circuit key to the production of estrogens during pregnancy. CRH induces cortisol production by the maternal and fetal adrenal glands, leading to further placental CRH production. CRH also stimulates the fetal adrenal glands to produce dehydroepiandrostendione sulfate (DHEAS), which the placenta converts into estrogens. There are at least two patterns of maternal circulating CRH across gestation among anthropoids. Monkeys examined to date (Papio and Callithrix) have an early-to-mid gestational peak of circulating CRH, followed by a steady decline to a plateau level, with a possible rise near parturition. In contrast, humans and great apes have an exponential rise in circulating CRH peaking at parturition. To further document and compare patterns of maternal circulating CRH in anthropoid primates, we collected monthly blood samples from 14 squirrel monkeys (Saimiri boliviensis) and ten owl monkeys (Aotus nancymaae) during pregnancy. CRH immunoreactivity was measured from extracted plasma by using solid-phase radioimmunoassay. Both squirrel and owl monkeys displayed a mid-gestational peak in circulating CRH: days 45-65 of the 152-day gestation for squirrel monkeys (mean±SEM CRH=2,694±276 pg/ml) and days 60-80 of the 133-day gestation for owl monkeys (9,871±974 pg/ml). In squirrel monkeys, circulating CRH declined to 36% of mean peak value by 2 weeks before parturition and then appeared to increase; the best model for circulating CRH over gestation in squirrel monkeys was a cubic function, similar to previous results for baboons and marmosets. In owl monkeys, circulating CRH appeared to reach plateau with no subsequent significant decline approaching parturition, although a cubic function was the best fit. This study provides additional evidence for a mid-gestational peak of maternal circulating CRH in ancestral

  17. Evidence that a Highway Reduces Apparent Survival Rates of Squirrel Gliders

    Directory of Open Access Journals (Sweden)

    Sarah C. McCall

    2010-09-01

    Full Text Available Roads and traffic are prominent components of most landscapes throughout the world, and their negative effects on the natural environment can extend for hundreds or thousands of meters beyond the road. These effects include mortality of wildlife due to collisions with vehicles, pollution of soil and air, modification of wildlife behavior in response to noise, creation of barriers to wildlife movement, and establishment of dispersal conduits for some plant and animal species. In southeast Australia, much of the remaining habitat for the squirrel glider, Petaurus norfolcensis, is located in narrow strips of Eucalyptus woodland that is adjacent to roads and streams, as well as in small patches of woodland vegetation that is farther from roads. We evaluated the effect of traffic volume on squirrel gliders by estimating apparent annual survival rates of adults along the Hume Freeway and nearby low-traffic-volume roads. We surveyed populations of squirrel gliders by trapping them over 2.5 years, and combined these data with prior information on apparent survival rates in populations located away from freeways to model the ratio of apparent annual survival rates in both site types. The apparent annual survival rate of adult squirrel gliders living along the Hume Freeway was estimated to be approximately 60% lower than for squirrel gliders living near local roads. The cause of the reduced apparent survival rate may be due to higher rates of mortality and/or higher emigration rates adjacent to the Hume Freeway compared with populations near smaller country roads. Management options for population persistence will be influenced by which of these factors is the primary cause of a reduced apparent survival rate.

  18. A. Hepatica in European ground squirrel (Citellus Citellus compared to other experimental animals

    Directory of Open Access Journals (Sweden)

    Blagojević Miloš

    2016-01-01

    Full Text Available European ground squirrel is the only representative of its genus in Serbia. It is used as experimental animal in microbioogy, parasitology, pharmacology and immunology. The objective of this work was to investigate a part of cardiovascular system of ground squirrel so in that way to contribute to a better knowledge of this animal body structure and accordingly to comparative anatomy in general. The investigation included 6 ground squirrels, of both gender, body weight 200-300 grams. For obtaining the liver arterial vascularization, after exsanguination of the animal, contrast mass of gelatin coloured with tempera was injected into abdominal aorta (Aorta abdominalis. After injecting, the blood vessels were prepared and photographed. In ground squirrel A. celiaca is odd, larger vessel that exits the abdominal aorta. It is divided into three branches: A. lienalis, A. gastrica sinistra and A. hepatica. A. hepatica is divided into A. hepatica propria and A. gastroduodenalis. A. hepatica propria further gives A. cystica, Rami cardiaci and small branches for Lnn. portales. A. gastroduodenalis is divided into A. pancreaticoduodenalis and A. gastroepiploica dextra. A. celiaca in nutria and rat is an odd artery, divided into A. lienalis, A. gastrica sinistra and A. hepatica. In rabbits, celiac artery (A. celiaca is divided into A. lienalis and short trunk from which A. gastrica sinistra and A. Hepatica emerge. A. celiaca in golden hamster does not exist in the form of tripus coeliacus (A. lienalis, A. gastrica sinistra and A. hepatica, but from A. celiaca it is firstly separated A. hepatica, and then short trunk from which A. gastrica sinistra and A. Lienalis emerge. In guinea-pig, from abdominal aorta a joint tree branches off into A. celiaca and A. mesenterica cranialis (Truncus celiacomesentericus. Based on the above mentioned results, it can be concluded that A. celiaca in European ground squirrel, nutria and rat branches from abdominal aorta as a

  19. Characterization of Monkeypox virus infection in African rope squirrels (Funisciurus sp.)

    Science.gov (United States)

    Falendysz, Elizabeth; Lopera, Juan G.; Doty, Jeffrey B.; Nakazawa, Yoshinori J.; Crill, Colleen; Lorenzsonn, Faye; Kalemba, Lem's N.; Ronderos, Monica; Meija, Andres; Malekani, Jean M.; Karem, Kevin L.; Caroll, Darrin; Osorio, Jorge E.; Rocke, Tonie E.

    2017-01-01

    Monkeypox (MPX) is a zoonotic disease endemic in Central and West Africa and is caused by Monkeypox virus (MPXV), the most virulent Orthopoxvirus affecting humans since the eradication of Variola virus (VARV). Many aspects of the MPXV transmission cycle, including the natural host of the virus, remain unknown. African rope squirrels (Funisciurus spp.) are considered potential reservoirs of MPXV, as serosurveillance data in Central Africa has confirmed the circulation of the virus in these rodent species [1,2]. In order to understand the tissue tropism and clinical signs associated with infection with MPXV in these species, wild-caught rope squirrels were experimentally infected via intranasal and intradermal exposure with a recombinant MPXV strain from Central Africa engineered to express the luciferase gene. After infection, we monitored viral replication and shedding via in vivo bioluminescent imaging, viral culture and real time PCR. MPXV infection in African rope squirrels caused mortality and moderate to severe morbidity, with clinical signs including pox lesions in the skin, eyes, mouth and nose, dyspnea, and profuse nasal discharge. Both intranasal and intradermal exposures induced high levels of viremia, fast systemic spread, and long periods of viral shedding. Shedding and luminescence peaked at day 6 post infection and was still detectable after 15 days. Interestingly, one sentinel animal, housed in the same room but in a separate cage, also developed severe MPX disease and was euthanized. This study indicates that MPXV causes significant pathology in African rope squirrels and infected rope squirrels shed large quantities of virus, supporting their role as a potential source of MPXV transmission to humans and other animals in endemic MPX regions.

  20. An annotated checklist of the horse flies, deer flies, and yellow flies (Diptera: Tabanidae) of Florida

    Science.gov (United States)

    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...

  1. Recording of calcium transient and analysis of calcium removal mechanisms in cardiac myocytes from rats and ground squirrels

    Institute of Scientific and Technical Information of China (English)

    王世强; 周曾铨; 钱洪

    2000-01-01

    With confocal microscopy, we recorded calcium transients and analyzed calcium removal rate at different temperatures in cardiac myocytes from the rat, a non-hibernator, and the ground squirrel, a hibernator. The results showed a remarkable increase of the diastolic level of calcium transients in the rat but no detectable change in the ground squirrel. Calcium transient of the ground squirrel, compared with that of the rat at the same temperature, had a shorter duration and showed a faster calcium removal. As indicated by the pharmacological effect of cyclopiazonic acid, calcium uptake by sarcoplasmic reticulum (SR) was the major mechanism of calcium removal, and was faster in the ground squirrel than in the rat. Our results confirmed the essential role of SR in hypothermia-tolerant adaptation, and negated the importance of Na-Ca exchange. We postulated the possibility to improve hypothermia-tolerance of the cardiac tissue of non-hibernating mammals.

  2. Note on breeding and parental care behaviours of albino Hoary-bellied Squirrel Callosciurus pygerythrus (Rodentia: Sciuridae in Sibsagar District of Assam, India

    Directory of Open Access Journals (Sweden)

    G. Kalita

    2009-06-01

    Full Text Available A few individuals of albino Horay-bellied Squirrels along with normal gray individuals of Callosciurus pygerythrus have been observed in Sibsagar district of Assam, India. One albino female was studied in captivity. This paper presents our observations on the breeding behaviour and the parental care exhibited by the albino squirrel in captivity. The squirrel bred twice in captivity with a normal male of the same species. In both the periods, a single male baby with normal coat colour developed. Oral dose of vitamin E has been found helpful in the breeding of the studied squirrel species. The mother squirrel exhibited parental care by carrying her baby using her mouth, to a safer place during danger. However, the observed phenomenon is unlike that of the cat species. Some of the habitat ecology and feeding habits of the albino squirrels have also been studied, both in natural and in captive conditions.

  3. The even darker side of the eastern gray squirrel (Sciurus carolinensis): a review of global introductions, invasion biology, and pest management strategies

    OpenAIRE

    McAlpine, D. F.; Thompson, C W; Williams, G. R.; Koprowski, J. L.; Lurz, P.W.W.; Bertolino, S.; Huynh, H. M.

    2011-01-01

    The eastern gray squirrel, Sciurus carolinensis, is one of the world’s most recognized sciurids and a highly successful human commensal. Historically restricted to eastern North America, gray squirrel populations are now established in Italy, U.K., South Africa, and Australia, and squirrels continue to expand their geographic range globally. Successful introductions of S. carolinensis often result in significant negative impacts on native ecosystem integrity. As a result, countries have devis...

  4. Flying Saucer? Aliens?

    Science.gov (United States)

    1961-01-01

    No, it's not a flying saucer, it is the domed top to a 70 foot long vacuum tank at the Lewis Research Center's Electric Propulsion Laboratory, Cleveland, Ohio. The three technicians shown here in protective clothing had just emerged from within the tank where they had been cleaning in the toxic mercury atmosphere, left after ion engine testing in the tank. Lewis has since been renamed the John H. Glenn Research Center.

  5. Consequences of artic ground squirrels on soil carbon loss from Siberian tundra

    Science.gov (United States)

    Golden, N. A.; Natali, S.; Zimov, N.

    2014-12-01

    A large pool of organic carbon (C) has been accumulating in the Arctic for thousands of years. Much of this C has been frozen in permafrost and unavailable for microbial decomposition. As the climate warms and permafrost thaws, the fate of this large C pool will be driven not only by climatic conditions, but also by ecosystem changes brought about by arctic animal populations. In this project we studied arctic ground squirrels (Spermophilus parryii), which are widely-distributed throughout the Arctic. These social mammals create subterranean burrows that mix soil layers, increase aeration, alter soil moisture and temperature, and redistribute soil nutrients, all of which may impact microbial decomposition. We examined the effects of arctic ground squirrel activity on soil C mineralization in dry heath tundra underlain by continuous permafrost in the Kolyma River watershed in northeast Siberia, Russia. Vegetation cover was greatly reduced on the ground squirrel burrows (80% of ground un-vegetated), compared to undisturbed sites (35% of ground un-vegetated). Soils from ground squirrel burrows were also significantly dryer and warmer. To examine effects of ground squirrel activity on microbial respiration, we conducted an 8-day incubation of soil fromburrows and from adjacent undisturbed tundra. In addition, we assessed the impact of nutrient addition by including treatments with low and high levels of nitrogen addition. Microbial respiration (per gram soil) was three-fold higher in incubated soils from the undisturbed sites compared to soils collected from the burrows. The lower rates of respiration from the disturbed soils may have been a result of lower carbon quality or low soil moisture. High nitrogen addition significantly increased respiration in the undisturbed soils, but not in the disturbed burrow soils, which suggests that microbial respiration in the burrow soils was not primarily limited by nitrogen. These results demonstrate the importance of wildlife

  6. No safety in the trees: Local and species-level adaptation of an arboreal squirrel to the venom of sympatric rattlesnakes.

    Science.gov (United States)

    Pomento, Abby M; Perry, Blair W; Denton, Robert D; Gibbs, H Lisle; Holding, Matthew L

    2016-08-01

    Within some species, squirrels respond to variable selection from venomous snake predators by showing population-level variation in resistance, while between species, some rattlesnakes possess venom that is more effective at overcoming venom resistance in different species of squirrels. A functional evaluation of resistance variation to venom within and between species of squirrels and snakes can link resistance variation to its evolutionary causes across these different evolutionary scales. To do this, we compared the effectiveness of squirrel sera in inhibiting rattlesnake (Crotalus spp.) venom metalloproteinase activity between populations and between species to test for a response to local variation in selection from a single rattlesnake predator and for specialization of two resistant squirrel species to each of their distinct sympatric snake predators. We found that Timber Rattlesnake (Crotalus horridus) venom inhibition by Eastern gray squirrels (Sciurus carolinensis) is higher at a site where the rattlesnakes are present, which suggests selection may maintain venom resistance in populations separated by short distances. Next, we performed a reciprocal cross of venoms and sera from two rattlesnake and two squirrel species. This showed that squirrel resistance is lower when tested against venom from allopatric compared to sympatric rattlesnake species, demonstrating that squirrel inhibitors are specialized to sympatric venom and suggesting a tradeoff in terms of specialization to the venom of a specific species of rattlesnake predator. This pattern can be explained if inhibitors must recognize venom proteins and resistance evolution tracks venom evolution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Suspension of mitotic activity in dentate gyrus of the hibernating ground squirrel.

    Science.gov (United States)

    Popov, Victor I; Kraev, Igor V; Ignat'ev, Dmitri A; Stewart, Michael G

    2011-01-01

    Neurogenesis occurs in the adult mammalian hippocampus, a region of the brain important for learning and memory. Hibernation in Siberian ground squirrels provides a natural model to study mitosis as the rapid fall in body temperature in 24 h (from 35-36°C to +4-6°C) permits accumulation of mitotic cells at different stages of the cell cycle. Histological methods used to study adult neurogenesis are limited largely to fixed tissue, and the mitotic state elucidated depends on the specific phase of mitosis at the time of day. However, using an immunohistochemical study of doublecortin (DCX) and BrdU-labelled neurons, we demonstrate that the dentate gyrus of the ground squirrel hippocampus contains a population of immature cells which appear to possess mitotic activity. Our data suggest that doublecortin-labelled immature cells exist in a mitotic state and may represent a renewable pool for generation of new neurons within the dentate gyrus.

  8. Molecular characterization of the first polyomavirus from a New World primate: squirrel monkey polyomavirus.

    Science.gov (United States)

    Verschoor, Ernst J; Groenewoud, Marlous J; Fagrouch, Zahra; Kewalapat, Aruna; van Gessel, Sabine; Kik, Marja J L; Heeney, Jonathan L

    2008-01-01

    DNA samples from a variety of New World monkeys were screened by using a broad-spectrum PCR targeting the VP1 gene of polyomaviruses. This resulted in the characterization of the first polyomavirus from a New World primate. This virus naturally infects squirrel monkeys (Saimiri sp.) and is provisionally named squirrel monkey polyomavirus (SquiPyV). The complete genome of SquiPyV is 5,075 bp in length, and encodes the small T and large T antigens and the three structural proteins VP1, VP2 and VP3. Interestingly, the late region also encodes a putative agnoprotein, a feature that it shares with other polyomaviruses from humans, baboons and African green monkeys. Comparison with other polyomaviruses revealed limited sequence similarity to any other polyomavirus, and phylogenetic analysis of the VP1 gene confirmed its uniqueness.

  9. Cryptosporidium rubeyi n. sp. (Apicomplexa: Cryptosporidiidae in multiple Spermophilus ground squirrel species

    Directory of Open Access Journals (Sweden)

    Xunde Li

    2015-12-01

    Full Text Available Previously we reported the unique Cryptosporidium sp. “c” genotype (e.g., Sbey03c, Sbey05c, Sbld05c, Sltl05c from three species of Spermophilus ground squirrel (Spermophilus beecheyi, Spermophilus beldingi, Spermophilus lateralis located throughout California, USA. This follow-up work characterizes the morphology and animal infectivity of this novel genotype as the final step in proposing it as a new species of Cryptosporidium. Analysis of sequences of 18S rRNA, actin, and HSP70 genes of additional Cryptosporidium isolates from recently sampled California ground squirrels (S. beecheyi confirms the presence of the unique Sbey-c genotype in S. beecheyi. Phylogenetic and BLAST analysis indicates that the c-genotype in Spermophilus ground squirrels is distinct from Cryptosporidium species/genotypes from other host species currently available in GenBank. We propose to name this c-genotype found in Spermophilus ground squirrels as Cryptosporidium rubeyi n. sp. The mean size of C. rubeyi n. sp. oocysts is 4.67 (4.4–5.0 μm × 4.34 (4.0–5.0 μm, with a length/width index of 1.08 (n = 220. Oocysts of C. rubeyi n. sp. are not infectious to neonatal BALB/c mice and Holstein calves. GenBank accession numbers for C. rubeyi n. sp. are DQ295012, AY462233, and KM010224 for the 18S rRNA gene, KM010227 for the actin gene, and KM010229 for the HSP70 gene.

  10. Vascularization of the kidney of the ground squirrel (Citellus citellus in comparison with other experimental animals

    Directory of Open Access Journals (Sweden)

    Blagojević Miloš

    2015-01-01

    Full Text Available Ground squirrel is the only representative of its genus in our country. As experimental animal is used in microbiology, parasitology, immunology and pharmacology. The aim of this study was to examine a part of ground squirrel cardiovascular system and thus help better understanding of anatomy of the body of this specific animal as well as to contribute to comparative anatomy. The studies were perfomed on six ground squirrels, both sexes, weight between 200- 300 g. In order to obtain the arterial vascularization of the kidney, contrast mass gelatin stained with painting tempera was injected into the abdominal aorta after bleeding out. After the injection, blood vessels were prepared and photographed. Corosive preparations of the vein blood vessels of the kidneys were obtained by injection of Byocril into the right azygos vein after bleeding out. After injection, the preparations were placed into 5% NaOH for 96 hours or 10% NaOH for 48 hours. After that the preparations were rinsed with hot water and photographed. A. renalis dextra arises from the lateral wall of the abdominal aorta, 3-4 mm caudal to A. mesenterica cranialis. In most cases, this vessel divides into two or three branches before entering the hilus of the right kidney. A. renalis sinistra arises from the lateral wall of the abdominal aorta, 7-9 mm caudal to the right renal artery. Often, instead of one left renal artery, there are two, rarely three. Based on the results of our study, we concluded that in ground squirrel there is one A. renalis dextra and often two, rarely three Aa. renales sinistrae. In renal venous vascularization, both right and left renal vein are involved. Before entering the kidney, both of them divide into cranial and caudal branch, undergoing renal hilus, enter the renal sinus and continues to branch out into smaller branches.

  11. Persistent maternal effects on juvenile survival in North American red squirrels

    OpenAIRE

    Kerr, Tricia D; Boutin, Stan; Jalene M. LaMontagne; McAdam, Andrew G; Humphries, Murray M.

    2007-01-01

    Maternal effects can have lasting fitness consequences for offspring, but these effects are often difficult to disentangle from associated responses in offspring traits. We studied persistent maternal effects on offspring survival in North American red squirrels (Tamiasciurus hudsonicus) by manipulating maternal nutrition without altering the post-emergent nutritional environment experienced by offspring. This was accomplished by providing supplemental food to reproductive females over winter...

  12. Mapping and monitoring Mount Graham red squirrel habitat with Lidar and Landsat imagery

    Science.gov (United States)

    Hatten, James R.

    2014-01-01

    The Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis) is an endemic subspecies located in the Pinaleño Mountains of southeast Arizona. Living in a conifer forest on a sky-island surrounded by desert, the Mount Graham red squirrel is one of the rarest mammals in North America. Over the last two decades, drought, insect infestations, and fire destroyed much of its habitat. A federal recovery team is working on a plan to recover the squirrel and detailed information is necessary on its habitat requirements and population dynamics. Toward that goal I developed and compared three probabilistic models of Mount Graham red squirrel habitat with a geographic information system and logistic regression. Each model contained the same topographic variables (slope, aspect, elevation), but the Landsat model contained a greenness variable (Normalized Difference Vegetation Index) extracted from Landsat, the Lidar model contained three forest-inventory variables extracted from lidar, while the Hybrid model contained Landsat and lidar variables. The Hybrid model produced the best habitat classification accuracy, followed by the Landsat and Lidar models, respectively. Landsat-derived forest greenness was the best predictor of habitat, followed by topographic (elevation, slope, aspect) and lidar (tree height, canopy bulk density, and live basal area) variables, respectively. The Landsat model's probabilities were significantly correlated with all 12 lidar variables, indicating its utility for habitat mapping. While the Hybrid model produced the best classification results, only the Landsat model was suitable for creating a habitat time series or habitat–population function between 1986 and 2013. The techniques I highlight should prove valuable in the development of Landsat- or lidar-based habitat models range wide.

  13. Leptin regulates energy intake but fails to facilitate hibernation in fattening Daurian ground squirrels (Spermophilus dauricus).

    Science.gov (United States)

    Xing, Xin; Tang, Gang-Bin; Sun, Ming-Yue; Yu, Chao; Song, Shi-Yi; Liu, Xin-Yu; Yang, Ming; Wang, De-Hua

    2016-04-01

    Body fat storage before hibernation affects the timing of immergence in Daurian ground squirrels (Spermophilus dauricus). Leptin is an adipose signal and plays vital role in energy homeostasis mainly by action in brain. To test the hypothesis that leptin plays a role in facilitating the process of hibernation, squirrels were administrated with recombinant murine leptin (1μg/day) through intracerebroventricular (ICV) injection for 12 days during fattening. From day 7 to 12, animals were moved into a cold room (5±1°C) with constant darkness which functioned as hibernaculum. Energy intake, body mass and core body temperature (Tb) were continuously monitored throughout the course of experiment. Resting metabolic rate (RMR) was measured under both warm and cold conditions. At the end of leptin administration, we measured the serum concentration of hormones related to energy regulation, mRNA expression of hypothalamic neuropeptides and uncoupling protein 1 (UCP1) levels in brown adipose tissue (BAT). Our results showed that during leptin administration, the cumulative food intake and increase of body mass were suppressed while Tb and RMR were unaltered. The proportion of torpid squirrels was not different between two groups. At the end of leptin administration, the expressions of hypothalamic neuropeptide Y and agouti gene-related protein were suppressed. There were no differences in UCP1 mRNA expression or protein content in BAT between groups. Our data suggest that leptin can affect energy intake via hypothalamic neuropeptides, but is not involved in the initiation of hibernation in fattening Daurian ground squirrels.

  14. Dielectric properties of fly ash

    Indian Academy of Sciences (India)

    S C Raghavendra; R L Raibagkar; A B Kulkarni

    2002-02-01

    This paper reports the dielectric properties of fly ash. The dielectric measurements were performed as a function of frequency and temperature. The sample of fly ash shows almost similar behaviour in the frequency and temperature range studied. The large value of dielectric constant in the typical frequency range is because of orientation polarization and tight binding force between the ions or atoms in the fly ash. The sample of fly ash is of great scientific and technological interest because of its high value of dielectric constant (104).

  15. Conservatism and adaptability during squirrel radiation: what is mandible shape telling us?

    Directory of Open Access Journals (Sweden)

    Isaac Casanovas-Vilar

    Full Text Available Both functional adaptation and phylogeny shape the morphology of taxa within clades. Herein we explore these two factors in an integrated way by analyzing shape and size variation in the mandible of extant squirrels using landmark-based geometric morphometrics in combination with a comparative phylogenetic analysis. Dietary specialization and locomotion were found to be reliable predictors of mandible shape, with the prediction by locomotion probably reflecting the underlying diet. In addition a weak but significant allometric effect could be demonstrated. Our results found a strong phylogenetic signal in the family as a whole as well as in the main clades, which is in agreement with the general notion of squirrels being a conservative group. This fact does not preclude functional explanations for mandible shape, but rather indicates that ancient adaptations kept a prominent role, with most genera having diverged little from their ancestral clade morphologies. Nevertheless, certain groups have evolved conspicuous adaptations that allow them to specialize on unique dietary resources. Such adaptations mostly occurred in the Callosciurinae and probably reflect their radiation into the numerous ecological niches of the tropical and subtropical forests of Southeastern Asia. Our dietary reconstruction for the oldest known fossil squirrels (Eocene, 36 million years ago show a specialization on nuts and seeds, implying that the development from protrogomorphous to sciuromorphous skulls was not necessarily related to a change in diet.

  16. An Experimental Test of Competition among Mice, Chipmunks, and Squirrels in Deciduous Forest Fragments.

    Directory of Open Access Journals (Sweden)

    Jesse L Brunner

    Full Text Available Mixed hardwood forests of the northeast United States support a guild of granivorous/omnivorous rodents including gray squirrels (Sciurus carolinensis, eastern chipmunks (Tamias striatus, and white-footed mice (Peromyscus leucopus. These species coincide geographically, co-occur locally, and consume similar food resources. Despite their idiosyncratic responses to landscape and patch variables, patch occupancy models suggest that competition may influence their respective distributions and abundances, and accordingly their influence on the rest of the forest community. Experimental studies, however, are wanting. We present the result of a large-scale experiment in which we removed white-footed mice or gray squirrels from small, isolated forest fragments in Dutchess County, New York, and added these mammals to other fragments in order to alter the abundance of these two species. We then used mark-recapture analyses to quantify the population-level and individual-level effects on resident mice, squirrels, and chipmunks. Overall, we found little evidence of competition. There were essentially no within-season numerical responses to changes in the abundance of putative competitors. Moreover, while individual-level responses (apparent survival and capture probability did vary with competitor densities in some models, these effects were often better explained by site-specific parameters and were restricted to few of the 19 sites we studied. With only weak or nonexistent competition among these three common rodent species, we expect their patterns of habitat occupancy and population dynamics to be largely independent of one another.

  17. Seasonal restructuring of the ground squirrel gut microbiota over the annual hibernation cycle.

    Science.gov (United States)

    Carey, Hannah V; Walters, William A; Knight, Rob

    2013-01-01

    Many hibernating mammals suspend food intake during winter, relying solely on stored lipids to fuel metabolism. Winter fasting in these species eliminates a major source of degradable substrates to support growth of gut microbes, which may affect microbial community structure and host-microbial interactions. We explored the effect of the annual hibernation cycle on gut microbiotas using deep sequencing of 16S rRNA genes from ground squirrel cecal contents. Squirrel microbiotas were dominated by members of the phyla Bacteroidetes, Firmicutes, and Verrucomicrobia. UniFrac analysis showed that microbiotas clustered strongly by season, and maternal influences, diet history, host age, and host body temperature had minimal effects. Phylogenetic diversity and numbers of operational taxonomic units were lowest in late winter and highest in the spring after a 2-wk period of refeeding. Hibernation increased relative abundance of Bacteroidetes and Verrucomicrobia, phyla that contain species capable of surviving on host-derived substrates such as mucins, and reduced relative abundance of Firmicutes, many of which prefer dietary polysaccharides. Hibernation reduced cecal short-chain fatty acid and ammonia concentrations, and increased and decreased concentrations of acetate and butyrate, respectively. These results indicate that the ground squirrel microbiota is restructured each year in a manner that reflects differences in microbial preferences for dietary vs. host-derived substrates, and thus the competitive abilities of different taxa to survive in the altered environment in the hibernator gut.

  18. Dietary fat unsaturation enhances drug metabolism in cebus but not in squirrel monkeys.

    Science.gov (United States)

    Meydani, M; Blumberg, J B; Hayes, K C

    1985-05-01

    Antipyrine disappearance and sleeping time following barbiturate anesthesia were assessed to evaluate the effects of dietary corn oil and coconut oil on the drug-metabolizing enzyme systems (DMES) in cebus (Cebus albifrons) and squirrel (Saimiri sciureus) monkeys. Plasma antipyrine clearance (half-life) was measured in both species before and after induction of DMES by i.v. injection of barbiturates on two consecutive days. Sleeping time was measured after administration of either pentobarbital or hexobarbital and proved to be the most demonstrable measure of diet-drug interaction. In neither cebus nor squirrel monkeys was antipyrine half-life significantly affected by dietary fat. Sleeping time for the coconut oil-fed squirrel monkeys was shorter than for those fed corn oil, whereas corn oil-fed cebus awoke sooner than the coconut oil-fed cebus. Thus, barbiturate but not antipyrine metabolism in monkeys can be influenced by dietary fat unsaturation, and the effect appears to be species dependent. Genetic differences in phospholipid metabolism are thought to underlie this difference.

  19. The adaptive function of masturbation in a promiscuous African ground squirrel.

    Directory of Open Access Journals (Sweden)

    Jane M Waterman

    Full Text Available BACKGROUND: Studies of animal mating systems increasingly emphasize female multiple mating and cryptic sexual selection, particularly sperm competition. Males under intense sperm competition may manipulate sperm quantity and quality through masturbation, which could waste sperm and decrease fertility. I examined the factors influencing masturbation by male Cape ground squirrels (Xerus inauris in light of a number of functional hypotheses. METHODOLOGY: Observational data on a marked population of squirrels were collected in east-central Namibia using scan and all-occurrences sampling. FINDINGS: Masturbation was far more frequent on days of female oestrus and mostly occurred after copulation. Masturbation rates were higher in dominant males, which copulate more, than in subordinates and increased with number of mates a female accepts. CONCLUSIONS: These results suggest that masturbation in this species was not a response to sperm competition nor a sexual outlet by subordinates that did not copulate. Instead masturbation could function as a form of genital grooming. Female Cape ground squirrels mate with up to 10 males in a 3-hr oestrus, and by masturbating after copulation males could reduce the chance of infection. Sexually transmitted infections (STIs can profoundly affect fertility, and their consequences for mating strategies need to be examined more fully.

  20. The ontogeny of kin-recognition mechanisms in Belding's ground squirrels.

    Science.gov (United States)

    Mateo, Jill M

    2017-05-01

    Despite extensive research on the functions and mechanisms of kin recognition, little is known about developmental changes in the abilities mediating such recognition. Belding's ground squirrels, Urocitellus beldingi, use at least two mechanisms of kin recognition in nepotistic contexts: familiarity and phenotype matching. Because recognition templates develop from early associations with familiar kin (and/or with self), familiarity-based recognition should precede phenotype-matching recognition even though one template is thought to be used for both mechanisms. I used a cross-fostering design to produce individuals that differed in relatedness and familiarity. Two pups (one female and one male) were exchanged reciprocally between two litters within 48-h of birth. Every five days, from 15 to 30-d of age, young were exposed to bedding and oral-gland odors from their familiar foster mother and an unfamiliar unrelated female (familiarity test) and from their unfamiliar genetic mother and another unfamiliar unrelated female (phenotype-matching test). As expected, discrimination of odors based on familiarity was evident at all ages tested, whereas discrimination based on relatedness was not evident until 30-d. My results provide a first estimate for when phenotype-matching mechanisms are used by young Belding's ground squirrels, and thus when they can recognize unfamiliar kin such as older sisters or grandmothers. Belding's ground squirrels are the first species for which the development of the production, perception and action components is well understood.

  1. Kin effects on energy allocation in group-living ground squirrels.

    Science.gov (United States)

    Viblanc, Vincent A; Saraux, Claire; Murie, Jan O; Dobson, F Stephen

    2016-09-01

    The social environment has potent effects on individual phenotype and fitness in group-living species. We asked whether the presence of kin might act on energy allocation, a central aspect of life-history variation. Using a 22-year data set on reproductive and somatic allocations in Columbian ground squirrels (Urocitellus columbianus), we tested the effects of co-breeding and non-breeding kin on the fitness and energy allocation balance between reproduction and personal body condition of individual females. Greater numbers of co-breeding kin had a positive effect on the number of offspring weaned, through the mechanism of altering energy allocation patterns. On average, females with higher numbers of co-breeding kin did not increase energy income but biased energy allocation towards reproduction. Co-breeding female kin ground squirrels maintain close nest burrows, likely providing a social buffer against territorial invasions from non-kin ground squirrels. Lower aggressiveness, lower risks of infanticide from female kin and greater protection of territorial boundaries may allow individual females to derive net fitness benefits via their energy allocation strategies. We demonstrated the importance of kin effects on a fundamental life-history trade-off.

  2. Host-pathogen dynamics of squirrelpox virus infection in red squirrels (Sciurus vulgaris).

    Science.gov (United States)

    Fiegna, C; Dagleish, M P; Coulter, L; Milne, E; Meredith, A; Finlayson, J; Di Nardo, A; McInnes, C J

    2016-01-01

    To improve our understanding of squirrelpox virus (SQPV) infection in the susceptible host, three red squirrels were challenged with wild-type SQPV via scarification of the hind-limb skin. All squirrels seroconverted to the infection by the end of the experiment (17 days post-challenge). Challenged animals suffered disease characterised by the development of multiple skin and oral lesions with rapid progression of skin lesions at the infection site by day 10 post-challenge. No internal pathological changes were found at post-mortem examination. A novel SQPV Taqman(®) Real-time PCR detected viral DNA from multiple organs, with the largest amounts consistently associated with the primary and secondary skin and oral lesions where viral replication was most likely occurring. Immunohistochemistry clearly detected viral antigen in the stratified squamous epithelium of the epidermis, tongue and the oropharyngeal mucosa-associated lymphoid tissue and was consistently associated with histological changes resulting from viral replication. The lack of internal pathological changes and the detection of relatively low levels of viral DNA when compared with primary and secondary skin lesions argue against systemic disease, although systemic spread of the virus cannot be ruled out. This study allowed a comprehensive investigation of the clinical manifestation and progression of SQPV infection with a quantitative and qualitative analysis of virus dissemination and shedding. These findings suggest two separate routes of SQPV transmission under natural conditions, with both skin and saliva playing key roles in infected red squirrels.

  3. Red squirrels from south–east Iberia: low genetic diversity at the southernmost species distribution limit

    Directory of Open Access Journals (Sweden)

    Lucas, J. M.

    2015-05-01

    Full Text Available South–east Iberia is the southernmost limit of this species in Europe. Squirrels in the region mainly inhabit coniferous forests of Pinus. In this study, we analyzed the pattern of mitochondrial genetic variation of southern Iberian red squirrels. Fragments of two mitochondrial genes, a 350–base pair of the displacement loop (D–loop and a 359–bp of the cytochrome b (Cytb, were sequenced using samples collected from 88 road–kill squirrels. The genetic variation was low, possibly explained by a recent bottleneck due to historical over–exploitation of forest resources. Habitat loss and fragmentation caused by deforestation and geographic isolation may explain the strong genetic subdivision between the study regions. Six new haplotypes for the D–loop and two new haplotypes for the Cytb fragments are described. A Cytb haplotype of south–east Iberia was found to be present in Albania and Japan, suggesting local extinction of this haplotype in intermediate areas. No significant clustering was found for the south–east of Spain or for the other European populations (except Calabria in the phylogenetic analysis.

  4. Flying over decades

    Science.gov (United States)

    Hoeller, Judith; Issler, Mena; Imamoglu, Atac

    Levy flights haven been extensively used in the past three decades to describe non-Brownian motion of particles. In this presentation I give an overview on how Levy flights have been used across several disciplines, ranging from biology to finance to physics. In our publication we describe how a single electron spin 'flies' when captured in quantum dot using the central spin model. At last I motivate the use of Levy flights for the description of anomalous diffusion in modern experiments, concretely to describe the lifetimes of quasi-particles in Josephson junctions. Finished PhD at ETH in Spring 2015.

  5. Vision in flying insects.

    Science.gov (United States)

    Egelhaaf, Martin; Kern, Roland

    2002-12-01

    Vision guides flight behaviour in numerous insects. Despite their small brain, insects easily outperform current man-made autonomous vehicles in many respects. Examples are the virtuosic chasing manoeuvres male flies perform as part of their mating behaviour and the ability of bees to assess, on the basis of visual motion cues, the distance travelled in a novel environment. Analyses at both the behavioural and neuronal levels are beginning to unveil reasons for such extraordinary capabilities of insects. One recipe for their success is the adaptation of visual information processing to the specific requirements of the behavioural tasks and to the specific spatiotemporal properties of the natural input.

  6. Fly ash quality and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Barta, L.E.; Lachner, L.; Wenzel, G.B. [Inst. for Energy, Budapest (Hungary); Beer, M.J. [Massachusetts Inst. of Technology, Cambridge, MA (United States)

    1995-12-01

    The quality of fly ash is of considerable importance to fly ash utilizers. The fly ash puzzolanic activity is one of the most important properties that determines the role of fly ash as a binding agent in the cementing process. The puzzolanic activity, however is a function of fly ash particle size and chemical composition. These parameters are closely related to the process of fly ash formation in pulverized coal fired furnaces. In turn, it is essential to understand the transformation of mineral matter during coal combustion. Due to the particle-to-particle variation of coal properties and the random coalescence of mineral particles, the properties of fly ash particles e.g. size, SiO{sub 2} content, viscosity can change considerably from particle to particle. These variations can be described by the use of the probability theory. Since the mean values of these randomly changing parameters are not sufficient to describe the behavior of individual fly ash particles during the formation of concrete, therefore it is necessary to investigate the distribution of these variables. Examples of these variations were examined by the Computer Controlled Scanning Electron Microscopy (CCSEM) for particle size and chemical composition for Texas lignite and Eagel Butte mineral matter and fly ash. The effect of combustion on the variations of these properties for both the fly ash and mineral matter were studied by using a laminar flow reactor. It is shown in our paper, that there are significant variations (about 40-50% around the mean values) of the above-listed properties for both coal samples. By comparing the particle size and chemical composition distributions of the mineral matter and fly ash, it was possible to conclude that for the Texas lignite mineral matter, the combustion did not effect significantly the distribution of these properties, however, for the Eagel Butte coal the combustion had a major impact on these mineral matter parameters.

  7. Physics of flying

    Science.gov (United States)

    Vetrone, Jim

    2015-05-01

    Column editor's note: As the school year comes to a close, it is important to start thinking about next year. One area that you want to consider is field trips. Many institutions require that teachers plan for a field trip well in advance. Keeping that in mind, I asked Jim Vetrone to write an article about the fantastic field trip he takes his AP Physics students on. I had the awesome opportunity to attend a professional development day that Jim arranged at iFLY in the Chicago suburbs. The experience of "flying" in a wind tunnel was fabulous. Equally fun was watching the other physics teachers come up with experiments to have the professional "flyers" perform in the tube. I could envision my students being similarly excited about the experience and about the development of their own experiments. After I returned to school, I immediately began the process of trying to get this field trip approved for the 2015-16 school year. I suggest that you start your process as well if you hope to try a new field trip next year. The key to getting the approval, in my experience, is submitting a proposal early that includes supporting documentation from sources. Often I use NGSS or state standards as justifications for my field trips. I have also quoted College Board expectations for AP Physics 1 and 2 in my documents when requesting an unusual field trip.quote>

  8. The application of the European strategy on invasive alien species: an example with introduced squirrels

    Directory of Open Access Journals (Sweden)

    Sandro Bertolino

    2005-06-01

    Full Text Available Abstract We assessed the cases of squirrel species already introduced into Italy inside the framework proposed by the European strategy on invasive alien species. We collected information on 9 introductions that originated 8 populations: 3 of grey squirrels (Sciurus carolinensis, 2 of Finlayson's squirrels (Callosciurus finlaysonii, and 3 of Siberian chip-munks (Eutamias sibiricus. Food opportunism and high reproductive rate may explain the high success rate in establishing new populations, even with a low propagule pressure. A negative impact on the red squirrel (Sciurus vulgaris and damage to forestry and manufactures have been recorded in the areas of introduction. Accordingly to the European strategy, Italy is called to build-up a rapid response system in order to avoid further releases of alien squirrels in the wild. Meanwhile these species must be considered as a priority for trade restriction. Considering the risks posed to biodiversity and human activities, Italy must adopt a precautionary principle, removing small nuclei of introduced species before they spread in large areas. Riassunto Applicazione della strategia europea sulle specie non indigene: un esempio con gli scoiattoli introdotti Come esempio di applicazione della strategia europea sulle specie invasive introdotte, abbiamo analizzato la situazione degli scoiattoli introdotti in Italia. Su 9 introduzioni registrate, in 8 casi si sono formate popolazioni naturalizzate: 3 di scoiattolo grigio (Sciurus carolinensis, 2 di scoiattolo di Finlayson (Callosciurus finlaysonii e 3 di tamia siberiano (Eutamias sibiricus. L'alto successo delle introduzioni, anche a partire da pochi animali rilasciati, è probabilmente legato all'opportunismo alimentare delle specie considerate e al loro elevato tasso riproduttivo. Al momento, nelle aree di introduzione sono segnalati fenomeni

  9. Refractive Index of Fly Rhabdomeres

    NARCIS (Netherlands)

    Stavenga, D.G.

    1974-01-01

    The refractive index reported previously for the rhabdomeres of flies (1.349) has been corrected for waveguide effects. The presented correction method has yielded n1 = 1.365 ± 0.006. It is argued that an acceptable estimate for the refractive index of the inhomogeneous surroundings of fly

  10. You can hide but you can't run: apparent competition, predator responses and the decline of Arctic ground squirrels in boreal forests of the southwest Yukon.

    Science.gov (United States)

    Werner, Jeffery R; Gillis, Elizabeth A; Boonstra, Rudy; Krebs, Charles J

    2016-01-01

    Throughout much of North America's boreal forest, the cyclical fluctuations of snowshoe hare populations (Lepus americanus) may cause other herbivores to become entrained in similar cycles. Alternating apparent competition via prey switching followed by positive indirect effects are the mechanisms behind this interaction. Our purpose is to document a change in the role of indirect interactions between sympatric populations of hares and arctic ground squirrels (Urocitellus parryii plesius), and to emphasize the influence of predation for controlling ground squirrel numbers. We used mark-recapture to estimate the population densities of both species over a 25-year period that covered two snowshoe hare cycles. We analysed the strength of association between snowshoe hare and ground squirrel numbers, and the changes to the seasonal and annual population growth rates of ground squirrels over time. A hyperbolic curve best describes the per capita rate of increase of ground squirrels relative to their population size, with a single stable equilibrium and a lower critical threshold below which populations drift to extinction. The crossing of this unstable boundary resulted in the subsequent uncoupling of ground squirrel and hare populations following the decline phase of their cycles in 1998. The implications are that this sustained Type II predator response led to the local extinction of ground squirrels. When few individuals are left in a colony, arctic ground squirrels may also have exhibited an Allee effect caused by the disruption of social signalling of approaching predators.

  11. You can hide but you can’t run: apparent competition, predator responses and the decline of Arctic ground squirrels in boreal forests of the southwest Yukon

    Science.gov (United States)

    Gillis, Elizabeth A.; Boonstra, Rudy; Krebs, Charles J.

    2016-01-01

    Throughout much of North America’s boreal forest, the cyclical fluctuations of snowshoe hare populations (Lepus americanus) may cause other herbivores to become entrained in similar cycles. Alternating apparent competition via prey switching followed by positive indirect effects are the mechanisms behind this interaction. Our purpose is to document a change in the role of indirect interactions between sympatric populations of hares and arctic ground squirrels (Urocitellus parryii plesius), and to emphasize the influence of predation for controlling ground squirrel numbers. We used mark-recapture to estimate the population densities of both species over a 25-year period that covered two snowshoe hare cycles. We analysed the strength of association between snowshoe hare and ground squirrel numbers, and the changes to the seasonal and annual population growth rates of ground squirrels over time. A hyperbolic curve best describes the per capita rate of increase of ground squirrels relative to their population size, with a single stable equilibrium and a lower critical threshold below which populations drift to extinction. The crossing of this unstable boundary resulted in the subsequent uncoupling of ground squirrel and hare populations following the decline phase of their cycles in 1998. The implications are that this sustained Type II predator response led to the local extinction of ground squirrels. When few individuals are left in a colony, arctic ground squirrels may also have exhibited an Allee effect caused by the disruption of social signalling of approaching predators. PMID:27635312

  12. You can hide but you can’t run: apparent competition, predator responses and the decline of Arctic ground squirrels in boreal forests of the southwest Yukon

    Directory of Open Access Journals (Sweden)

    Jeffery R. Werner

    2016-08-01

    Full Text Available Throughout much of North America’s boreal forest, the cyclical fluctuations of snowshoe hare populations (Lepus americanus may cause other herbivores to become entrained in similar cycles. Alternating apparent competition via prey switching followed by positive indirect effects are the mechanisms behind this interaction. Our purpose is to document a change in the role of indirect interactions between sympatric populations of hares and arctic ground squirrels (Urocitellus parryii plesius, and to emphasize the influence of predation for controlling ground squirrel numbers. We used mark-recapture to estimate the population densities of both species over a 25-year period that covered two snowshoe hare cycles. We analysed the strength of association between snowshoe hare and ground squirrel numbers, and the changes to the seasonal and annual population growth rates of ground squirrels over time. A hyperbolic curve best describes the per capita rate of increase of ground squirrels relative to their population size, with a single stable equilibrium and a lower critical threshold below which populations drift to extinction. The crossing of this unstable boundary resulted in the subsequent uncoupling of ground squirrel and hare populations following the decline phase of their cycles in 1998. The implications are that this sustained Type II predator response led to the local extinction of ground squirrels. When few individuals are left in a colony, arctic ground squirrels may also have exhibited an Allee effect caused by the disruption of social signalling of approaching predators.

  13. Use of LiDAR in the conservation management of the endangered red squirrel (Sciurus vulgaris L.)

    Science.gov (United States)

    Flaherty, Silvia; Lurz, Peter W. W.; Patenaude, Genevieve

    2014-01-01

    LiDAR remote sensing allows the direct retrieval of vegetation structure parameters and has been widely used to assess habitat quality for various species. The aim of this study is to test whether LiDAR can help in providing estimates of habitat suitability over larger scales and inform conservation management planning in stronghold areas of an endangered forest mammal, the red squirrel (Sciurus vulgaris L.). The Eurasian red squirrel is endangered in the UK and under strict legal protection. Hence, long-term habitat management is a key goal of the UK conservation strategy. This involves understanding habitat preferences of the species. In a previous study, we demonstrated the importance of forest structure for red squirrels' habitat preference. We used a general linear model (GLM) to relate the distribution and abundance of squirrel feeding signs to mean canopy closure, mean tree height, and the total number of trees at the plot level. However, this analysis was limited to a few sample areas. In the current study, we implement the GLM using LiDAR-derived explanatory variables in Abernethy Forest. Results suggest that when forest structure is considered, only 27% of the total forest area is highly suitable for red squirrel. Implications for management are discussed.

  14. Shape optimization of 3D curved slots and its application to the squirrel-cage elastic support design

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The squirrel-cage elastic support is one of the most important components of an aero-engine rotor system.A proper structural design will favor the static and dynamic performances of the system.In view of the deficiency of the current shape optimization techniques,a new mapping approach is proposed to define shape design variables based on the parametric equations of 3D curves and surfaces.It is then applied for the slot shape optimization of a squirrel-cage elastic support.To this end,an automatic design procedure that integrates the Genetic Algorithm (GA) is developed to solve the problem.Two typical examples with different shape constraints are considered.Numerical results provide reasonable optimum designs for the improvement of stiffness and strength of the squirrel-cage elastic support.

  15. Determination of an optimal dose of medetomidine-ketamine-buprenorphine for anaesthesia in the Cape ground squirrel (Xerus inauris

    Directory of Open Access Journals (Sweden)

    K. E. Joubert

    2011-04-01

    Full Text Available The optimal dose of medetomidine-ketamine-buprenorphine was determined in 25 Cape ground squirrels (Xerus inauris undergoing surgical implantation of a temperature logger into the abdominal cavity. At the end of anaesthesia, the squirrels were given atipamezole intramuscularly to reverse the effects of medetomidine. The mean dose of medetomidine was 67.6±9.2 μg/kg, ketamine 13.6±1.9 mg/kg and buprenorphine 0.5±0.06 μg/kg. Induction time was 3.1 ± 1.4 min. This produced surgical anaesthesia for 21± 4.2 min. Atipamezole 232±92 μg/kg produced a rapid recovery. Squirrels were sternally recumbent in 3.5 ± 2.2 min.

  16. An experimental study investigating the ability of volunteers to identify squirrel species from tail–hair samples

    Directory of Open Access Journals (Sweden)

    Shearer, L.

    2014-12-01

    Full Text Available Hair–tubes, collecting nape hairs, are widely used for establishing the presence of red (Sciurus vulgaris and grey (Sciurus carolinensis squirrels. However it is time–consuming and prone to identification errors. An alternative is to collect tail hairs from sticky pads on baited poles. However, there is no evidence concerning identification accuracy of tail hairs. This study reports an experiment in which subjects underwent a short training session before identifying hair samples from four species. There was a 96.5% correct identification rate for grey squirrel hairs, and 77.5% for red squirrels, which suggests that tail hairs collection may provide a quick, easy and accurate method of identification for both species.

  17. Catenotaenia dendritica (Cestoda: Catenotaeniidae) and Three Ectoparasite Species in the Red Squirrel, Sciurus vulgaris, from Cheongju, Korea.

    Science.gov (United States)

    Choe, Seongjun; Lee, Dongmin; Park, Hansol; Jeon, Hyeong-Kyu; Lee, Youngsun; Na, Ki-Jeong; Lee, In-Yong; Eom, Keeseon S

    2016-08-01

    Parasites are recorded from the red squirrel, Sciurus vulgaris, from Cheongju, the Republic of Korea. A total of 5 road-killed squirrels were thoroughly examined for internal and external parasites from November 2011 to May 2014. Total 4 parasite species, including 1 tapeworm and 3 ectoparasite species were recovered. They were morphologically identified as Catenotaenia dendritica (Cestoda: Catenotaeniidae), Hirstionyssus sciurinus, Leptotrombidium pallidum, and Ceratophyllus (Monopsyllus) indages. Among them, C. dendritica and H. sciurinus are recorded for the first time in the Korean parasite fauna. In addition, the possibility that the red squirrel could act as a reservoir host for a zoonotic disease like tsutsugamushi disease with L. pallidum as its vector has been raised.

  18. Yersiniosis caused by Yersinia pseudotuberculosis in captive toucans (Ramphastidae) and a Japanese squirrel (Sciurus lis) in zoological gardens in Japan.

    Science.gov (United States)

    Nakamura, Shin-ichi; Hayashidani, Hideki; Sotohira, Yukari; Une, Yumi

    2016-02-01

    Two captive Keel-billed toucans and a Chestnut-mandibled toucan in another zoological garden died suddenly without any pre-existing symptoms, and three months later, a Japanese squirrel died of diarrhea. All these animals showed necrotic enteritis and multifocal necrosis in the liver and spleen with Gram negative bacilli. The bacilli showed strong positive immunolabeling for Yersinia pseudotuberculosis O4 in the Keel-billed toucans, Y. pseudotuberculosis O2 in the Chestnut-mandibled toucan and Y. pseudotuberculosis O1 in the Japanese squirrel, while Y. pseudotuberculosis 4b, 2b and 1b were respectively isolated from the lesions. To our knowledge, this might be the first reported case of fatal yersiniosis in a Japanese squirrel in the world as well as in toucans in Japan.

  19. Effects of low temperature on breathing pattern and ventilatory responses during hibernation in the golden-mantled ground squirrel.

    Science.gov (United States)

    Webb, Cheryl L; Milsom, William K

    2017-07-01

    During entrance into hibernation in golden-mantled ground squirrels (Callospermophilus lateralis), ventilation decreases as metabolic rate and body temperature fall. Two patterns of respiration occur during deep hibernation. At 7 °C body temperature (T b ), a breathing pattern characterized by episodes of multiple breaths (20.6 ± 1.9 breaths/episode) separated by long apneas or nonventilatory periods (T nvp ) (mean = 11.1 ± 1.2 min) occurs, while at 4 °C T b , a pattern in which breaths are evenly distributed and separated by a relatively short T nvp (0.5 ± 0.05 min) occurs. Squirrels exhibiting each pattern have similar metabolic rates and levels of total ventilation (0.2 and 0.23 ml O2/hr/kg and 0.11 and 0.16 ml air/min/kg, respectively). Squirrels at 7 °C T b exhibit a significant hypoxic ventilatory response, while squirrels at 4 °C T b do not respond to hypoxia at any level of O2 tested. Squirrels at both temperatures exhibit a significant hypercapnic ventilatory response, but the response is significantly reduced in the 4 °C T b squirrels. Carotid body denervation has little effect on the breathing patterns or on the hypercapnic ventilatory responses. It does reduce the magnitude and threshold for the hypoxic ventilatory response. Taken together the data suggest that (1) the fundamental rhythm generator remains functional at low temperatures; (2) the hypercapnic ventilatory response arises from central chemoreceptors that remain functional at very low temperatures; (3) the hypoxic ventilatory response arises from both carotid body and aortic chemoreceptors that are silenced at lower temperatures; and (4) there is a strong correlation between breathing pattern and chemosensitivity.

  20. Roll Control in Fruit Flies

    CERN Document Server

    Beatus, Tsevi; Cohen, Itai

    2014-01-01

    Due to aerodynamic instabilities, stabilizing flapping flight requires ever-present fast corrective actions. Here we investigate how flies control body roll angle, their most susceptible degree of freedom. We glue a magnet to each fly, apply a short magnetic pulse that rolls it in mid-air, and film the corrective maneuver. Flies correct perturbations of up to $100^{\\circ}$ within $30\\pm7\\mathrm{ms}$ by applying a stroke-amplitude asymmetry that is well described by a linear PI controller. The response latency is $\\sim5\\mathrm{ms}$, making the roll correction reflex one of the fastest in the animal kingdom.

  1. Living on the edge: Space use of Eurasian red squirrels in marginal high-elevation habitat

    Science.gov (United States)

    Romeo, Claudia; Wauters, Lucas A.; Preatoni, Damiano; Tosi, Guido; Martinoli, Adriano

    2010-11-01

    In marginal habitats located at the edge of a species' range, environmental conditions are frequently extreme and individuals may be subject to different selective pressures compared to central populations. These so-called edge or marginal populations tend to have lower densities and reproductive rates than populations located in more suitable habitats, but little is known about local adaptations in spacing behavior. We studied space use and social organization in a population of Eurasian red squirrels ( Sciurus vulgaris) in a high-elevation marginal habitat of dwarf mountain pine ( Pinus mugo) and compared it with spacing patterns in high-quality Scots pine ( Pinus sylvestris) forest at lower-elevation. Home ranges and core areas were larger in the marginal habitat. In both habitats, males used larger home ranges than females, but sex differences in core area size were significant only in the edge population. Patterns of core area overlap were similar in both habitats with intra-sexual territoriality among adult females and higher degrees of inter-sexual overlap, typical for the species throughout its range. However, low densities in the edge population resulted in higher female by males overlap in spring-summer, suggesting males increased home ranges and core areas during mating season to augment access to estrus females. Thus, in the marginal habitat, with low food abundance and low population densities, linked with extreme winter conditions, squirrels, especially males, used large home ranges. Finally, squirrels responded more strongly to variation in food availability (inverse relation between home range size and seed abundance), and even to fluctuations in density (inverse relation between core area size and density of animals of the same sex), in the marginal than in the high-quality habitat, suggesting high behavioral plasticity to respond to the ecological constraints in marginal habitats.

  2. Food availability and animal space use both determine cache density of Eurasian red squirrels.

    Directory of Open Access Journals (Sweden)

    Ke Rong

    Full Text Available Scatter hoarders are not able to defend their caches. A longer hoarding distance combined with lower cache density can reduce cache losses but increase the costs of hoarding and retrieving. Scatter hoarders arrange their cache density to achieve an optimal balance between hoarding costs and main cache losses. We conducted systematic cache sampling investigations to estimate the effects of food availability on cache patterns of Eurasian red squirrels (Sciurus vulgaris. This study was conducted over a five-year period at two sample plots in a Korean pine (Pinus koraiensis-dominated forest with contrasting seed production patterns. During these investigations, the locations of nest trees were treated as indicators of squirrel space use to explore how space use affected cache pattern. The squirrels selectively hoarded heavier pine seeds farther away from seed-bearing trees. The heaviest seeds were placed in caches around nest trees regardless of the nest tree location, and this placement was not in response to decreased food availability. The cache density declined with the hoarding distance. Cache density was lower at sites with lower seed production and during poor seed years. During seed mast years, the cache density around nest trees was higher and invariant. The pine seeds were dispersed over a larger distance when seed availability was lower. Our results suggest that 1 animal space use is an important factor that affects food hoarding distance and associated cache densities, 2 animals employ different hoarding strategies based on food availability, and 3 seed dispersal outside the original stand is stimulated in poor seed years.

  3. Investigation of anti-motion sickness drugs in the squirrel monkey

    Science.gov (United States)

    Cheung, B. S.; Money, K. E.; Kohl, R. L.; Kinter, L. B.

    1992-01-01

    Early attempts to develop an animal model for anti-motion sickness drugs, using dogs and cats; were unsuccessful. Dogs did not show a beneficial effect of scopolamine (probably the best single anti-motion sickness drug for humans thus far) and the findings in cats were not definitive. The authors have developed an animal model using the squirrel monkey (Saimiri sciureus) of the Bolivian phenotype. Unrestrained monkeys in a small lucite cage were tested in an apparatus that induces motion sickness by combining vertical oscillation and horizontal rotation in a visually unrestricted laboratory environment. Signs of motion sickness were scored using a rating scale. Ten susceptible monkeys (weighing 800-1000 g) were given a total of five tests each, to establish the baseline susceptibility level. Based on the anticholinergic activity of scopolamine, the sensitivity of squirrel monkey to scopolamine was investigated, and the appropriate dose of scopolamine for this species was determined. Then various anti-motion sickness preparations were administered in subsequent tests: 100 ug scopolamine per monkey; 140 ug dexedrine; 50 ug scopolamine plus 70 ug dexedrine; 100 ug scopolamine plus 140 ug dexedrine; 3 mg promethazine; 3 mg promethazine plus 3 mg ephedrine. All these preparations were significantly effective in preventing motion sickness in the monkeys. Ephedrine, by itself, which is marginally effective in humans, was ineffective in the monkeys at the doses tried (0.3-6.0 mg). The squirrel monkey appears to be a good animal model for antimotion sickness drugs. Peripherally acting antihistamines such as astemizole and terfenadine were found to be ineffective, whereas flunarizine, and an arginine vasopressin V1 antagonist, showed significant activity in preventing motion sickness.

  4. Integrating histology and MRI in the first digital brain of common squirrel monkey, Saimiri sciureus.

    Science.gov (United States)

    Sun, Peizhen; Parvathaneni, Prasanna; Schilling, Kurt G; Gao, Yurui; Janve, Vaibhav; Anderson, Adam; Landman, Bennett A

    2015-03-17

    This effort is a continuation of development of a digital brain atlas of the common squirrel monkey, Saimiri sciureus, a New World monkey with functional and microstructural organization of central nervous system similar to that of humans. Here, we present the integration of histology with multi-modal magnetic resonance imaging (MRI) atlas constructed from the brain of an adult female squirrel monkey. The central concept of this work is to use block face photography to establish an intermediate common space in coordinate system which preserves the high resolution in-plane resolution of histology while enabling 3-D correspondence with MRI. In vivo MRI acquisitions include high resolution T2 structural imaging (300 µm isotropic) and low resolution diffusion tensor imaging (600 um isotropic). Ex vivo MRI acquisitions include high resolution T2 structural imaging and high resolution diffusion tensor imaging (both 300 µm isotropic). Cortical regions were manually annotated on the co-registered volumes based on published histological sections in-plane. We describe mapping of histology and MRI based data of the common squirrel monkey and construction of a viewing tool that enable online viewing of these datasets. The previously descried atlas MRI is used for its deformation to provide accurate conformation to the MRI, thus adding information at the histological level to the MRI volume. This paper presents the mapping of single 2D image slice in block face as a proof of concept and this can be extended to map the atlas space in 3D coordinate system as part of the future work and can be loaded to an XNAT system for further use.

  5. Influence of experimental history on nicotine self-administration in squirrel monkeys.

    Science.gov (United States)

    Desai, Rajeev I; Sullivan, Katherine A; Kohut, Stephen J; Bergman, Jack

    2016-06-01

    Methods for establishing robust long-term self-administration of intravenous (i.v.) nicotine, the primary psychoactive agent in tobacco, are not well-established in laboratory animals. Here, we examine the use of a fading procedure to establish robust and consistent i.v. nicotine self-administration under second-order schedule conditions in squirrel monkeys. First, self-administration behavior was developed in two groups of male squirrel monkeys using a second-order fixed-interval 5-min schedule with fixed-ratio 5 units (FI 5-min (FR5: S)). Comparable performances were maintained by i.v. cocaine (0.032 mg/kg/injection (inj); group A, n = 3) and the combination of food delivery (20-30 % condensed milk) and 0.01 mg/kg/inj i.v. nicotine (group B, n = 3). Subsequently, the concentration of condensed milk was gradually reduced to zero in the second group and self-administration behavior was maintained by i.v. nicotine alone. Next, self-administration of a range of doses of i.v. nicotine (0.001-0.032 mg/kg/inj) and, in additional experiments, the minor tobacco alkaloid anatabine (0.01-0.18 mg/kg/inj) was studied in both groups. Results show that nicotine and anatabine had reinforcing effects in both groups. However, optimal doses of nicotine and anatabine maintained significantly higher rates of i.v. self-administration behavior in subjects trained with the fading procedure than in subjects provided with a history of cocaine-maintained responding. These results illustrate conditions under which robust i.v. nicotine self-administration can be established in squirrel monkeys and the influence of prior experimental history in the expression of reinforcing effects of nicotine and anatabine.

  6. Integrating histology and MRI in the first digital brain of common squirrel monkey, Saimiri sciureus

    Science.gov (United States)

    Sun, Peizhen; Parvathaneni, Prasanna; Schilling, Kurt G.; Gao, Yurui; Janve, Vaibhav; Anderson, Adam; Landman, Bennett A.

    2015-03-01

    This effort is a continuation of development of a digital brain atlas of the common squirrel monkey, Saimiri sciureus, a New World monkey with functional and microstructural organization of central nervous system similar to that of humans. Here, we present the integration of histology with multi-modal magnetic resonance imaging (MRI) atlas constructed from the brain of an adult female squirrel monkey. The central concept of this work is to use block face photography to establish an intermediate common space in coordinate system which preserves the high resolution in-plane resolution of histology while enabling 3-D correspondence with MRI. In vivo MRI acquisitions include high resolution T2 structural imaging (300 μm isotropic) and low resolution diffusion tensor imaging (600 um isotropic). Ex vivo MRI acquisitions include high resolution T2 structural imaging and high resolution diffusion tensor imaging (both 300 μm isotropic). Cortical regions were manually annotated on the co-registered volumes based on published histological sections in-plane. We describe mapping of histology and MRI based data of the common squirrel monkey and construction of a viewing tool that enable online viewing of these datasets. The previously descried atlas MRI is used for its deformation to provide accurate conformation to the MRI, thus adding information at the histological level to the MRI volume. This paper presents the mapping of single 2D image slice in block face as a proof of concept and this can be extended to map the atlas space in 3D coordinate system as part of the future work and can be loaded to an XNAT system for further use.

  7. Anatomy and Disorders of the Oral Cavity of Rat-like and Squirrel-like Rodents.

    Science.gov (United States)

    Mancinelli, Elisabetta; Capello, Vittorio

    2016-09-01

    The order Rodentia comprises more than 2000 species divided into 3 groups based on anatomic and functional differences of the masseter muscle. Myomorph and sciuromorph species have elodont incisors and anelodont cheek teeth, unlike hystrichomorph species which have full anelodont dentition. Diseases of incisors and cheek teeth of rat-like and squirrel-like rodents result in a wide variety of symptoms and clinical signs. Appropriate diagnostic testing and imaging techniques are required to obtain a definitive diagnosis, formulate a prognosis, and develop a treatment plan. A thorough review of elodontoma, odontoma, and pseudo-odontoma is provided, including treatment of pseudo-odontomas in prairie dogs.

  8. Effect of physical exercise prelabyrinthectomy on locomotor balance compensation in the squirrel monkey

    Science.gov (United States)

    Igarashi, M.; Ohashi, K.; Yoshihara, T.; MacDonald, S.

    1989-01-01

    This study examines the effectiveness of physical exercise, during a prepathology state, on locomotor balance compensation after subsequent unilateral labyrinthectomy in squirrel monkeys. An experimental group underwent 3 hr. of daily running exercise on a treadmill for 3 mo. prior to the surgery, whereas a control group was not exercised. Postoperatively, the locomotor balance function of both groups was tested for 3 mo. There was no significant difference in gait deviation counts in the acute phase of compensation. However, in the chronic compensation maintenance phase, the number of gait deviation counts was fewer in the exercise group, which showed significantly better performance stability.

  9. Diagnosis of Wind Energy System Faults Part I : Modeling of the Squirrel Cage Induction Generator

    Directory of Open Access Journals (Sweden)

    Lahcène Noureddine

    2015-08-01

    Full Text Available Generating electrical power from wind energy is becoming increasingly important throughout the world. This fast development has attracted many researchers and electrical engineers to work on this field. The authors develop a dynamic model of the squirrel cage induction generator exists usually on wind energy systems, for the diagnosis of broken rotor bars defects from an approach of magnetically coupled multiple circuits. The generalized model is established on the base of mathematical recurrences. The winding function theory is used for determining the rotor resistances and the inductances in the case of n- broken bars. Simulation results, in Part. II of this paper, confirm the validity of the proposed model.

  10. Jacqueline Yallop, Magpies, Squirrels & Thieves: How the Victorians Collected the World

    OpenAIRE

    Constanty-Roussillon, Laurence

    2013-01-01

    If you’ve never tracked down a ceramic pot of the Ming period that once belonged to a famous painter or experienced the thrill of rummaging through flea-market stalls just feeling that something might attract your desiring hand, beware: Jacqueline Yallop’s latest book, Magpies, Squirrels & Thieves: How the Victorians Collected the World might just be an eye-opener and turn you into one of those relentless collectors depicted in this fascinating book. As the author clearly states in the prefa...

  11. Managing the Fruit Fly Experiment.

    Science.gov (United States)

    Jeszenszky, Arleen W.

    1997-01-01

    Describes a sophisticated version of the fruit fly experiment for teaching concepts about genetics to biology students. Provides students with the opportunity to work with live animals over an extended period. (JRH)

  12. Quantitative proteomics on the fly

    NARCIS (Netherlands)

    Gouw, J.W.

    2009-01-01

    The development of multicellular organisms is characterized by complex processes that progressively transform essentially a single cell into a creature with complicated structures and highly specialized functions. The fruit fly Drosophila melanogaster provides an excellent model system to investigat

  13. Subtropical Fruit Fly Invasions into Temperate Fruit Fly Territory in California's San Joaquin Valley

    Science.gov (United States)

    Subtropical fruit fly species including peach fruit fly, Bactrocera zonata (Saunders); melon fly, B. cucurbitae (Coquillett); oriental fruit fly, B. dorsalis (Hendel); and Mediterranean fruit fly, Ceratitis capitata Weidemann, have been detected in the past decade in the San Joaquin Valley of Califo...

  14. Flying in Two Dimensions

    CERN Document Server

    Prakash, Manu

    2011-01-01

    Diversity and specialization of behavior in insects is unmatched. Insects hop, walk, run, jump, row, swim, glide and fly to propel themselves in a variety of environments. We have uncovered an unusual mode of propulsion of aerodynamic flight in two dimensions in Waterlilly Beetles \\emph{(Galerucella)}. The adult beetles, often found in water lilly ponds, propel themselves strictly in a two-dimensional plane on the surface of water via flapping wing flight. Here we analyze the aerodynamics of this peculiar flight mode with respect to forces exerted on the organism during flight. The complexity of 2-D flight is captured by accounting for additional forces beyond gravitational, thrust, lift and drag, exerted on the insect body in 3D flight. Understanding this constrained propulsion mode requires accounting for viscous drag, surface tension, buoyancy force, and capillary-wave drag. Moreover, dramatic differences exist in the magnitude of the resultant forces in 2D vs. 3D flight. Here, in this fluid dynamics video...

  15. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.

    1996-11-01

    Imatran Voima`s coal-fired power plants not only generate power and heat but also produce fly ash which is suitable raw material for recycling. This material for recycling is produced in the flue gas cleaning process. It is economical and, thanks to close quality control, is suitable for use as a raw material in the building materials industry, in asphalt production, and in earthworks. Structures made from fly ash are also safe from an environmental point of view. (orig.)

  16. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.

    1996-11-01

    Imatran Voima`s coal-fired power plants not only generate power and heat but also produce fly ash which is suitable raw material for recycling. This material for recycling is produced in the flue gas cleaning process. It is economical and, thanks to close quality control, is suitable for use as a raw material in the building materials industry, in asphalt production, and in earthworks. Structures made from fly ash are also safe from an environmental point of view. (orig.)

  17. Acoustic analysis of the alarm call of the Anatolian ground squirrel Spermophilus xanthoprymnus: a description and comparison with alarm calls of the Taurus S. taurensis and European S. citellus ground squirrels

    Science.gov (United States)

    Schneiderová, Irena; Policht, Richard

    2012-01-01

    The Anatolian ground squirrel Spermophilus xanthoprymnus like other ground-dwelling sciurids, emits alarm calls in the presence of predators. In this study, we provide a description of the acoustic structure of alarm call of this species and compare it to those of two closely related species, the Taurus ground squirrel Spermophilus taurensis and the European ground squirrel Spermophilus citellus. The alarm call of S. xanthoprymnus is a tonal sound mostly consisting of two different elements—the first element has low frequency modulation while the second element is highly frequency modulated. A similar basic structure can be found in the alarm calls of some other old world ground squirrel species of the genus Spermophilus, including S. taurensis and S. citellus. Despite this similarity, we found that these three species can be clearly distinguished on the basis of their alarm calls. Differences in the acoustic structure of S. xanthoprymnus and S. taurensis calls are especially remarkable, as these two species were considered to be conspecific until 2007. S. xanthoprymnus and S. taurensis were also demonstrated to have closer acoustic similarity, which is in contrast to results based on molecular data indicating that S. taurensis is most closely related to S. citellus.

  18. Suspension of Mitotic Activity in Dentate Gyrus of the Hibernating Ground Squirrel

    Directory of Open Access Journals (Sweden)

    Victor I. Popov

    2011-01-01

    Full Text Available Neurogenesis occurs in the adult mammalian hippocampus, a region of the brain important for learning and memory. Hibernation in Siberian ground squirrels provides a natural model to study mitosis as the rapid fall in body temperature in 24 h (from 35-36°C to +4–6°C permits accumulation of mitotic cells at different stages of the cell cycle. Histological methods used to study adult neurogenesis are limited largely to fixed tissue, and the mitotic state elucidated depends on the specific phase of mitosis at the time of day. However, using an immunohistochemical study of doublecortin (DCX and BrdU-labelled neurons, we demonstrate that the dentate gyrus of the ground squirrel hippocampus contains a population of immature cells which appear to possess mitotic activity. Our data suggest that doublecortin-labelled immature cells exist in a mitotic state and may represent a renewable pool for generation of new neurons within the dentate gyrus.

  19. Comparison of ponderosa pines as feed and nonfeed trees for abert squirrels.

    Science.gov (United States)

    Pederson, J C; Welch, B L

    1985-02-01

    Twigs from five ponderosa pine trees (Pinus ponderosa) used by Abert squirrels (Sciurus aberti) as feed trees and five nonfeed trees were collected every 45 days and their monoterpenoid and nutrient content determined. Thet tests (unpaired observations) detected no significant difference in the level of monoterpenoids in the outer bark of feed (0.77%) and nonfeed (0.75%) trees. The same was true for inner bark of feed (0.10%) and nonfeed (0.16%) trees. Monoterpenoid levels in outer bark (0.75%) were significantly higher than inner bark (0.13%). The inner bark is what is eaten by Abert squirrels. Protein and other nutrients did not differ significantly between feed and nonfeed trees. However, both outer and inner bark were easier to remove from the woody portion of the feed tree twigs than those twigs collected from nonfeed trees. Therefore, due to the lack of differences in monoterpenoid and nutrient content between feed and nonfeed trees, we attributed the use of certain trees for use as feed trees to the ease of peeling and separating outer from inner bark.

  20. Note on the Giant Woolly Gliding Squirrel Eupetaurus cinereus (Mammalia: Rodentia: Sciuridae in northern Pakistan

    Directory of Open Access Journals (Sweden)

    Jaffar Ud Din

    2015-07-01

    Full Text Available The Woolly Gliding Squirrel Eupetaurus cinereus is an extremely rare, localized, and endangered mammal and may constitute one of the endemic species of Pakistan. The species was rediscovered in northern Pakistan in the mid-1990s after a 70-year absence of records. All the previous information regarding this giant squirrel was limited to museum specimens, collected mostly from areas presently in northern Pakistan in the late 1800s. Sighting of the species is extremely challenging owing to its nocturnal behavior, low densities and the inhospitable terrain it is reported from. Here we report detailed information about the species collected during the rescue of a young male individual from Gilgit City followed by its successful release in its natural habitat. We report that the species is still facing human-induced threats and may disappear from the mountains of northern Pakistan if informed management measures are not taken. Moreover, the occurrence of the species outside its core distribution range, i.e., districts Gilgit and Diamer, still remains questionable; therefore, it is recommended that further in-depth research studies be undertaken to determine the status of the species across the entire reported range. 

  1. Foraging density for squirrel monkey Saimiri sciureus in two forests in Puerto Lopez - Colombia

    Directory of Open Access Journals (Sweden)

    Jorge Astwood R.

    2014-06-01

    Full Text Available Objective. Forest remnants were analyzed to determine the density of squirrel monkeys (Saimiri sciureus and the degree of alteration of the forest, by selecting areas for the conservation and maintenance of the species in natural environments. Materials and methods. Linear transects were conducted on two wooden fragments, “La Reforma” and “Campo Hermoso” farms (Puerto Lopez, Meta, Colombia, recording sightings of squirrel monkeys and identifying the tree species used by the primates. Results. The fragments studied correspond to trails at the edge of water bodies with low connectivity. Highest density values were observed on the second transect of La Reforma, a possible consequence of an overcrowding phenomenon due to the high degree of isolation of the fragment. The species preferentially used as refuge and food source were: Bellucia grossularioides, Eugenia jambos, Inga alba, Mauritia flexuosa, Pseudolmedia laevis and Rollinia edulis. Conclusions. The phenology of the plant species allows for a dynamic food supply, considering the constant availability of food for the primates. Therefore, despite the evident ecological problem of these forests, it is possible to use active restoration programs to strengthen the existing dynamics and balance the biogeochemical dynamics of the ecosystem, so that socioeconomic human activities are not in conflict with conservation efforts and vice versa.

  2. Note on the Giant Woolly Gliding Squirrel Eupetaurus cinereus (Mammalia: Rodentia: Sciuridae in northern Pakistan

    Directory of Open Access Journals (Sweden)

    Jaffar Ud Din

    2015-07-01

    Full Text Available The Woolly Gliding Squirrel Eupetaurus cinereus is an extremely rare, localized, and endangered mammal and may constitute one of the endemic species of Pakistan. The species was rediscovered in northern Pakistan in the mid-1990s after a 70-year absence of records. All the previous information regarding this giant squirrel was limited to museum specimens, collected mostly from areas presently in northern Pakistan in the late 1800s. Sighting of the species is extremely challenging owing to its nocturnal behavior, low densities and the inhospitable terrain it is reported from. Here we report detailed information about the species collected during the rescue of a young male individual from Gilgit City followed by its successful release in its natural habitat. We report that the species is still facing human-induced threats and may disappear from the mountains of northern Pakistan if informed management measures are not taken. Moreover, the occurrence of the species outside its core distribution range, i.e., districts Gilgit and Diamer, still remains questionable; therefore, it is recommended that further in-depth research studies be undertaken to determine the status of the species across the entire reported range. 

  3. Absolute, not relative brain size correlates with sociality in ground squirrels.

    Science.gov (United States)

    Matějů, Jan; Kratochvíl, Lukáš; Pavelková, Zuzana; Pavelková Řičánková, Věra; Vohralík, Vladimír; Němec, Pavel

    2016-03-30

    The social brain hypothesis (SBH) contends that cognitive demands associated with living in cohesive social groups favour the evolution of large brains. Although the correlation between relative brain size and sociality reported in various groups of birds and mammals provides broad empirical support for this hypothesis, it has never been tested in rodents, the largest mammalian order. Here, we test the predictions of the SBH in the ground squirrels from the tribe Marmotini. These rodents exhibit levels of sociality ranging from solitary and single-family female kin groups to egalitarian polygynous harems but feature similar ecologies and life-history traits. We found little support for the association between increase in sociality and increase in relative brain size. Thus, sociality does not drive the evolution of encephalization in this group of rodents, a finding inconsistent with the SBH. However, body mass and absolute brain size increase with sociality. These findings suggest that increased social complexity in the ground squirrels goes hand in hand with larger body mass and brain size, which are tightly coupled to each other.

  4. Community ecology and disease risk: lizards, squirrels, and the Lyme disease spirochete in California, USA.

    Science.gov (United States)

    Salkeld, Daniel J; Lane, Robert S

    2010-01-01

    Vector-borne zoonotic diseases are often maintained in complex transmission cycles involving multiple vertebrate hosts and their arthropod vectors. In the state of California, U.S.A., the spirochete Borrelia burgdorferi, which causes Lyme disease, is transmitted between vertebrate hosts by the western black-legged tick, Ixodes pacificus. Several mammalian species serve as reservoir hosts of the spirochete, but levels of tick infestation, reservoir competence, and Borrelia-infection prevalence vary widely among such hosts. Here, we model the host (lizards, Peromyscus mice, Californian meadow voles, dusky-footed wood rats, and western gray squirrels), vector, and pathogen community of oak woodlands in northwestern California to determine the relative importance of different tick hosts. Observed infection prevalence of B. burgdorferi in host-seeking I. pacificus nymphs was 1.8-5.3%, and our host-community model estimated an infection prevalence of 1.6-2.2%. The western gray squirrel (Sciurus griseus) was the only source of infected nymphs. Lizards, which are refractory to Borrelia infection, are important in feeding subadult ticks but reduce disease risk (nymphal infection prevalence). Species identity is therefore critical in understanding and determining the local disease ecology.

  5. Effect of Environmental Enrichment on Singly- and Group-Housed Squirrel Monkeys

    Science.gov (United States)

    Spring, Sarah E.; Clifford, James O.; Tomko, David L.; Hargens, Alan R. (Technical Monitor)

    1996-01-01

    Nonhuman primates display an interest in novel places, habituate to new situations, and spend most of their daily activity in the wild in large groups engaging in feeding behaviors. Captivity changes these behaviors, and disrupts normal social hierarchies. In captivity, animals may exhibit stereotypical behaviors which are thought to indicate decreased psychological well-being (PWB). If an animal's behaviors can be made to approach those seen in the wild, and stereotypical behaviors are minimal it is assumed that PWB is adequate. Environmental enrichment (EE) devices have been used to address the Animal Welfare Act's requirement that the PWB of captive nonhuman primates be considered. The purpose of the present study was to examine whether various EE devices improve the PWB of captive squirrel monkeys. The present study used behavioral observation to quantify the effectiveness of several EE devices in reducing stereotypical behaviors in squirrel monkeys housed singly or in groups. Results showed that the EE devices used did not affect the expression of normal or stereotypical behaviors, but that the type of housing did.

  6. Impaired skeletal muscle regeneration in the absence of fibrosis during hibernation in 13-lined ground squirrels.

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    Eva Andres-Mateos

    Full Text Available Skeletal muscle atrophy can occur as a consequence of immobilization and/or starvation in the majority of vertebrates studied. In contrast, hibernating mammals are protected against the loss of muscle mass despite long periods of inactivity and lack of food intake. Resident muscle-specific stem cells (satellite cells are known to be activated by muscle injury and their activation contributes to the regeneration of muscle, but whether satellite cells play a role in hibernation is unknown. In the hibernating 13-lined ground squirrel we show that muscles ablated of satellite cells were still protected against atrophy, demonstrating that satellite cells are not involved in the maintenance of skeletal muscle during hibernation. Additionally, hibernating skeletal muscle showed extremely slow regeneration in response to injury, due to repression of satellite cell activation and myoblast differentiation caused by a fine-tuned interplay of p21, myostatin, MAPK, and Wnt signaling pathways. Interestingly, despite long periods of inflammation and lack of efficient regeneration, injured skeletal muscle from hibernating animals did not develop fibrosis and was capable of complete recovery when animals emerged naturally from hibernation. We propose that hibernating squirrels represent a new model system that permits evaluation of impaired skeletal muscle remodeling in the absence of formation of tissue fibrosis.

  7. Advanced Model of Squirrel Cage Induction Machine for Broken Rotor Bars Fault Using Multi Indicators

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    Ilias Ouachtouk

    2016-01-01

    Full Text Available Squirrel cage induction machine are the most commonly used electrical drives, but like any other machine, they are vulnerable to faults. Among the widespread failures of the induction machine there are rotor faults. This paper focuses on the detection of broken rotor bars fault using multi-indicator. However, diagnostics of asynchronous machine rotor faults can be accomplished by analysing the anomalies of machine local variable such as torque, magnetic flux, stator current and neutral voltage signature analysis. The aim of this research is to summarize the existing models and to develop new models of squirrel cage induction motors with consideration of the neutral voltage and to study the effect of broken rotor bars on the different electrical quantities such as the park currents, torque, stator currents and neutral voltage. The performance of the model was assessed by comparing the simulation and experimental results. The obtained results show the effectiveness of the model, and allow detection and diagnosis of these defects.

  8. Diversification and gene flow in nascent lineages of island and mainland North American tree squirrels (Tamiasciurus).

    Science.gov (United States)

    Chavez, Andreas S; Maher, Sean P; Arbogast, Brian S; Kenagy, G J

    2014-04-01

    Pleistocene climate cycles and glaciations had profound impacts on taxon diversification in the Boreal Forest Biome. Using population genetic analyses with multilocus data, we examined diversification, isolation, and hybridization in two sibling species of tree squirrels (Tamiasciurus douglasii and Tamiasciurus hudsonicus) with special attention to the geographically and genetically enigmatic population of T. hudsonicus on Vancouver Island, Canada. The two species differentiated only about 500,000 years ago, in the Late Pleistocene. The island population is phylogenetically nested within T. hudsonicus according to our nuclear analysis but within T. douglasii according to mitochondrial DNA. This conflict is more likely due to historical hybridization than to incomplete lineage sorting, and it appears that bidirectional gene flow occurred between the island population and both species on the mainland. This interpretation of our genetic analyses is consistent with our bioclimatic modeling, which demonstrates that both species were able to occupy this region throughout the Late Pleistocene. The divergence of the island population 40,000 years ago suggests that tree squirrels persisted in a refugium on Vancouver Island at the last glacial maximum, 20,000 years ago. Our observations demonstrate how Pleistocene climate change and habitat shifts have created incipient divergence in the presence of gene flow. Sequence data have been archived in GenBank—accession numbers: KF882736–KF885216.

  9. Laryngeal biomechanics and vocal communication in the squirrel monkey (Saimiri boliviensis)

    Science.gov (United States)

    Brown, Charles H.; Alipour, Fariborz; Berry, David A.; Montequin, Douglas

    2003-04-01

    The larynges of eight squirrel monkeys were harvested, dissected, mounted on a pseudotracheal tube, and phonated using compressed air. Patterns of vocal fold oscillation were compared with sound spectrograms of calls recorded from monkeys in our colony. Four different regimes of vocal fold activation were identified. Regime 1 resembled typical human vowel production, with regular vocal-fold vibration, a prominent fundamental frequency, and an accompanying series of harmonic overtones. This regime is likely to give rise to squirrel monkey ``cackles,'' as well as a variety of other harmonically structured calls. In regime 2, the pattern of vibrations exhibited the presence of two or more unrelated frequencies (biphonation). This regime of glottal activity resembled the biphonation observed in many exemplars of ``twitter'' and ``kecker'' calls. The vocal folds oscillated continuously in regime 3, but produced glottal pulses whose amplitudes waxed and waned rhythmically. This phenomenon resulted in the percept of a series of discrete pulses, and may give rise to ``errs,'' ``churrs,'' and other calls composed of a rapid sequence of acoustic elements. In regime 4, the period of each oscillation was quasi-irregular. Shrieks and other broadband calls or call elements that lack an apparent fundamental frequency may be produced in this manner.

  10. Expression profiling and structural characterization of microRNAs in adipose tissues of hibernating ground squirrels.

    Science.gov (United States)

    Wu, Cheng-Wei; Biggar, Kyle K; Storey, Kenneth B

    2014-12-01

    MicroRNAs (miRNAs) are small non-coding RNAs that are important in regulating metabolic stress. In this study, we determined the expression and structural characteristics of 20 miRNAs in brown (BAT) and white adipose tissue (WAT) during torpor in thirteen-lined ground squirrels. Using a modified stem-loop technique, we found that during torpor, expression of six miRNAs including let-7a, let-7b, miR-107, miR-150, miR-222 and miR-31 was significantly downregulated in WAT (Pstructure-influenced changes in pre-miRNA processing efficiency in the squirrel. As well, the expression of miRNA processing enzyme Dicer remained unchanged in both tissues during torpor. Overall, our findings suggest that changes of miRNA expression in adipose tissues may be linked to distinct biological roles in WAT and BAT during hibernation and may involve the regulation of signaling cascades.

  11. Changes in calpains and calpastatin in the soleus muscle of Daurian ground squirrels during hibernation.

    Science.gov (United States)

    Yang, Chen-Xi; He, Yue; Gao, Yun-Fang; Wang, Hui-Ping; Goswami, Nandu

    2014-10-01

    We investigated changes in muscle mass, calpains, calpastatin and Z-disk ultrastructure in the soleus muscle (SOL) of Daurian ground squirrels (Spermophilus dauricus) after hibernation or hindlimb suspension to determine possible mechanisms by which muscle atrophy is prevented in hibernators. Squirrels (n=30) were divided into five groups: no hibernation group (PRE, n=6); hindlimb suspension group (HLS, n=6); two month hibernation group (HIB, n=6); two day group after 90±12 days of hibernation (POST, n=6); and forced exercise group (one time forced, moderate-intensity treadmill exercise) after arousal (FE, n=6). Activity and protein expression of calpains were determined by casein zymography and western blotting, and Z-disk ultrastructure was observed by transmission electron microscopy. The following results were found. Lower body mass and higher SOL muscle mass (mg) to total body mass (g) ratio were observed in HIB and POST; calpain-1 activity increased significantly by 176% (P=0.034) in HLS compared to the PRE group; no significant changes were observed in calpain-2 activity. Protein expression of calpain-1 and calpain-2 increased by 83% (P=0.041) and 208% (P=0.029) in HLS compared to the PRE group, respectively; calpastatin expression increased significantly by 180% (Pcalpain activity and consequently calpain-mediated protein degradation by highly elevated calpastatin protein expression levels may be an important mechanism for preventing muscle protein loss during hibernation and ensuring that Z-lines remained ultrastructurally intact.

  12. Caching in the presence of competitors: Are Cape ground squirrels (Xerus inauris) sensitive to audience attentiveness?

    Science.gov (United States)

    Samson, Jamie; Manser, Marta B

    2016-01-01

    When social animals cache food close to their burrow, the potential for an audience member to observe the event is significantly increased. As a consequence, in order to reduce theft it may be advantageous for animals to be sensitive to certain audience cues, such as whether they are attentive or not to the cache event. In this study, observations were made on three groups of Cape ground squirrels (Xerus inauris) in their natural habitat when they cached provisioned food items. When individuals cached within 10 m of conspecifics, we recorded the attentiveness (i.e. whether any audience members were orientated towards the cacher, had direct line of site and were not engaged in other activities) and identity of audience members. Overall, there was a preference to cache when audience members were inattentive rather than attentive. Additionally, we found rank effects related to cache avoidance whereby high-ranked individuals showed less avoidance to cache when audience members were attentive compared to medium- and low-ranked individuals. We suggest this audience sensitivity may have evolved in response to the difference in competitive ability amongst the ranks in how successful individuals are at winning foraging competitions. This study demonstrates that Cape ground squirrels have the ability to not only monitor the presence or absence of conspecifics but also discriminate individuals on the basis of their attentive state.

  13. Squirrel monkeys (Saimiri sciureus) infected with the agent of bovine spongiform encephalopathy develop tau pathology.

    Science.gov (United States)

    Piccardo, P; Cervenak, J; Yakovleva, O; Gregori, L; Pomeroy, K; Cook, A; Muhammad, F S; Seuberlich, T; Cervenakova, L; Asher, D M

    2012-07-01

    Squirrel monkeys (Saimiri sciureus) were infected experimentally with the agent of classical bovine spongiform encephalopathy (BSE). Two to four years later, six of the monkeys developed alterations in interactive behaviour and cognition and other neurological signs typical of transmissible spongiform encephalopathy (TSE). At necropsy examination, the brains from all of the monkeys showed pathological changes similar to those described in variant Creutzfeldt-Jakob disease (vCJD) of man, except that the squirrel monkey brains contained no PrP-amyloid plaques typical of that disease. Constant neuropathological features included spongiform degeneration, gliosis, deposition of abnormal prion protein (PrP(TSE)) and many deposits of abnormally phosphorylated tau protein (p-Tau) in several areas of the cerebrum and cerebellum. Western blots showed large amounts of proteinase K-resistant prion protein in the central nervous system. The striking absence of PrP plaques (prominent in brains of cynomolgus macaques [Macaca fascicularis] with experimentally-induced BSE and vCJD and in human patients with vCJD) reinforces the conclusion that the host plays a major role in determining the neuropathology of TSEs. Results of this study suggest that p-Tau, found in the brains of all BSE-infected monkeys, might play a role in the pathogenesis of TSEs. Whether p-Tau contributes to development of disease or appears as a secondary change late in the course of illness remains to be determined.

  14. Finite Element Analysis of Squirrel Cage Ball Bearingsfor Gas Turbine Engines

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    Benny George

    2007-03-01

    Full Text Available Squirrel cage ball bearings are used in recent aero engines to overcome the vibration andstability problems associated with rotor systems supported by conventional bearings. The criticaldesign feature of squirrel cage bearing is to provide flexible support to rotor system. The outerring of the bearing is configured such that it acts as a flexible bearing support, and hence, weightis minimised. The bearing is mounted directly on a rigid intermediate casing of a gas turbineengine. Finite element analysis helps to obtain a suitable geometry at the design stage. A 3-Dmodel of the bearing is created using IDEAS software. Finite element analysis using contactelement has been carried out for finding the deformation and stresses in the webs at variouslocations using ANSYS software. The deformations are compared with those of experimentalvalues for an axial load. The deformation in the webs is used to check the pressure balance inthe compressor and the load acting on the bearing. Finally, a procedure for doing the finiteelement analysis of ball bearings for combined axial and radial load is laid down.

  15. Cone consumption by southeastern fox squirrels: A potential basis for clonal preferences in a loblolly and slash pine seed orchard

    Science.gov (United States)

    Christopher Asaro; Susan C. Loeb; James L. Hanula

    2003-01-01

    Southeastern fox squirrels were observed feeding preferentially on seeds of certain clones of loblolly pine in a central Georgia seed orchard in the early 1990s and, similarly, on slash pine seed in an orchard in central Florida in the late 1990s. In each orchard, the degree of feeding preference and avoidance among selected clones was documented and quantified. We...

  16. Effects of GABA[subscript A] Modulators on the Repeated Acquisition of Response Sequences in Squirrel Monkeys

    Science.gov (United States)

    Campbell, Una C.; Winsauer, Peter J.; Stevenson, Michael W.; Moerschbaecher, Joseph M.

    2004-01-01

    The present study investigated the effects of positive and negative GABA[subscript A] modulators under three different baselines of repeated acquisition in squirrel monkeys in which the monkeys acquired a three-response sequence on three keys under a second-order fixed-ratio (FR) schedule of food reinforcement. In two of these baselines, the…

  17. Segregating the Effects of Seed Traits and Common Ancestry of Hardwood Trees on Eastern Gray Squirrel Foraging Decisions.

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    Mekala Sundaram

    Full Text Available The evolution of specific seed traits in scatter-hoarded tree species often has been attributed to granivore foraging behavior. However, the degree to which foraging investments and seed traits correlate with phylogenetic relationships among trees remains unexplored. We presented seeds of 23 different hardwood tree species (families Betulaceae, Fagaceae, Juglandaceae to eastern gray squirrels (Sciurus carolinensis, and measured the time and distance travelled by squirrels that consumed or cached each seed. We estimated 11 physical and chemical seed traits for each species, and the phylogenetic relationships between the 23 hardwood trees. Variance partitioning revealed that considerable variation in foraging investment was attributable to seed traits alone (27-73%, and combined effects of seed traits and phylogeny of hardwood trees (5-55%. A phylogenetic PCA (pPCA on seed traits and tree phylogeny resulted in 2 "global" axes of traits that were phylogenetically autocorrelated at the family and genus level and a third "local" axis in which traits were not phylogenetically autocorrelated. Collectively, these axes explained 30-76% of the variation in squirrel foraging investments. The first global pPCA axis, which produced large scores for seed species with thin shells, low lipid and high carbohydrate content, was negatively related to time to consume and cache seeds and travel distance to cache. The second global pPCA axis, which produced large scores for seeds with high protein, low tannin and low dormancy levels, was an important predictor of consumption time only. The local pPCA axis primarily reflected kernel mass. Although it explained only 12% of the variation in trait space and was not autocorrelated among phylogenetic clades, the local axis was related to all four squirrel foraging investments. Squirrel foraging behaviors are influenced by a combination of phylogenetically conserved and more evolutionarily labile seed traits that is

  18. Selective mobilization of saturated fatty acids in isolated adipocytes of hibernating 13-lined ground squirrels Ictidomys tridecemlineatus.

    Science.gov (United States)

    Price, Edwin R; Armstrong, Christopher; Guglielmo, Christopher G; Staples, James F

    2013-01-01

    Fatty acids are not mobilized from adipocyte triacylglycerols uniformly but rather some are preferentially mobilized while others are preferentially retained. In many vertebrate species, the pattern of differential mobilization is determined by the physical and chemical properties of each fatty acid. Fatty acids with shorter chains and more double bonds tend to be more readily mobilized than others, a pattern observed both in whole-animal studies and in isolated adipocytes. Several hibernating species seem to break this pattern, however, and retain 18:2ω6 (linoleic acid) while mobilizing saturated fatty acids such as 18:0. We sought to confirm this pattern in adipocytes of a hibernator, the 13-lined ground squirrel Ictidomys tridecemlineatus, and to investigate mobilization patterns for the first time at hibernation temperature. We isolated adipocytes from summer active and winter torpid squirrels and incubated them with 1 μM norepinephrine at 4°C (7 h) and 37°C (90 min). We measured the proportion of each fatty acid in the adipose tissue and in the buffer at the end of incubation. Patterns of mobilization were similar in both seasons and incubation temperatures. Saturated fatty acids (18:0 and 16:0) were highly mobilized relative to the average, while some unsaturated fatty acids (notably, 18:1ω9 and 18:2ω6) were retained. We conclude that hibernators have unique mechanisms at the level of adipose tissue that preferentially mobilize saturated fatty acids. Additionally, we found that adipocytes from hibernating squirrels produced more glycerol than those from summer squirrels (regardless of temperature), indicating a higher lipolytic capacity in hibernating squirrels.

  19. Fiber optics that fly

    Science.gov (United States)

    Wilcox, Michael J.; Thelen, Donald C., Jr.

    1996-11-01

    The need for autonomous systems to work under unanticipated conditions requires the use of smart sensors. High resolution systems develop tremendous computational loads. Inspiration from animal vision systems can guide us in developing preprocessing approaches implementable in real time with high resolution and deduced computational load. Given a high quality optical path and a 2D array of photodetectors, the resolution of a digital image is determined by the density of photodetectors sampling the image. In order to reconstruct an image, resolution is limited by the distance between adjacent detectors. However, animal eyes resolve images 10-100 times better than either the acceptance angle of a single photodetector or the center-to-center distance between neighboring photodetectors. A new model of the fly's visual system emulates this improved performance, offering a different approach to subpixel resolution. That an animal without a cortex is capable of this performance suggests that high level computation is not involved. The model takes advantage of a photoreceptor cell's internal structure for capturing light. This organelle is a waveguide. Neurocircuitry exploits the waveguide's optical nonlinearities, namely in the shoulder region of its gaussian sensitivity-profile, to extract high resolution information from the visual scene. The receptive fields of optically disparate inputs overlap in space. Photoreceptor input is continuous rather than discretely sampled. The output of the integrating module is a signal proportional to the position of the target within the detector array. For tracking a point source, resolution is 10 times better than the detector spacing. For locating absolute position and orientation of an edge, the model performs similarly. Analog processing is used throughout. Each element is an independent processor of local luminance. Information processing is in real time with continuous update. This processing principle will be reproduced in an

  20. Fly-in/Fly-out: Implications for Community Sustainability

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    Keith Storey

    2010-04-01

    Full Text Available “Fly-in/fly-out” is a form of work organization that has become the standard model for new mining, petroleum and other types of resource development in remote areas. In many places this “no town” model has replaced that of the “new town.” The work system has both beneficial and adverse implications for the sustainability of both existing communities near new resource developments and for the more distant communities from which workers are drawn. This paper explores these outcomes drawing upon examples from North America and Australia.

  1. Escherichia coli fliAZY operon.

    OpenAIRE

    Mytelka, D S; Chamberlin, M J

    1996-01-01

    We have cloned the Escherichia coli fliAZY operon, which contains the fliA gene (the alternative sigma factor sigma F) and two novel genes, fliZ and fliY. Transcriptional mapping of this operon shows two start sites, one of which is preceded by a canonical E sigma F-dependent consensus and is dependent on sigma F for expression in vivo and in vitro. We have overexpressed and purified sigma F and demonstrated that it can direct core polymerase to E sigma F-dependent promoters. FliZ and FliY ar...

  2. Present Status and Habitat Survey of the Delmarva Fox Squirrel (Sciurus niger cinereus) with a Discussion of Reasons For Its Decline.

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The recovery plan for Demarva Fox Squirrel on Chesapeake Marshlands Complex discusses the current status of the species, habitat requirements and limiting factors,...

  3. Photomonitoring of Delmarva Fox Squirrel (Sciurus niger cinereus, DFS) on the Prime Hook National Wildlife Refuge during the summer of 2008.

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The primary goal of this photomonitoring was to determine the status of the Prime Hook National Wildlife Refuge Delmarva Fox Squirrel population. The Photomonitor...

  4. Prime Hook National Wildlife Refuge Photo-Arrays of Delmarva Fox Squirrel (DFS) and Photomonitoring Summary for the Spring and Summer of 2011

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The primary goal of this photomonitoring effort was to determine the status of Prime Hook National Widlife Refuge (PHNWR) Delmarva Fox Squirrel (Sciurus niger...

  5. Dermatobia, the neotropical warble fly.

    Science.gov (United States)

    Sancho, E

    1988-09-01

    The neotropical warble fly, Dermatobia hominis (Fig. 1), has plagued neotropical America since preColombian times, and has become an economically important pest causing substantial losses to the meat, milk and leather industries from northern Mexico down to northern Argentina. Its life cycle (Box 1) is astonishingly complex, requiring another insect as a phoretic carrier of its eggs to the skin of its mammal hosts. Here Eugenio Sancho discusses factors that contribute to the current economic and public health importance of this myiasis-causing fly.

  6. Susceptibility of low-chill blueberry cultivars to Mediterranean fruit fly, oriental fruit fly, and melon fly (Diptera: Tephritidae).

    Science.gov (United States)

    Follett, Peter A; Zee, Francis T; Hamasaki, Randall T; Hummer, Kim; Nakamoto, Stuart T

    2011-04-01

    No-choice tests were conducted to determine whether fruit of southern highbush blueberry, Vaccinium corymbosum L., hybrids are hosts for three invasive tephritid fruit flies in Hawaii. Fruit of various blueberry cultivars was exposed to gravid female flies of Bactrocera dorsalis Hendel (oriental fruit fly), Ceratitis capitata (Wiedemann) (Mediterranean fruit fly), or Bactrocera cucurbitae Coquillet (melon fly) in screen cages outdoors for 6 h and then held on sand in the laboratory for 2 wk for pupal development and adult emergence. Each of the 15 blueberry cultivars tested were infested by oriental fruit fly and Mediterranean fruit fly, confirming that these fruit flies will oviposit on blueberry fruit and that blueberry is a suitable host for fly development. However, there was significant cultivar variation in susceptibility to fruit fly infestation. For oriental fruit fly, 'Sapphire' fruit produced an average of 1.42 puparia per g, twice as high as that of the next most susceptible cultivar 'Emerald' (0.70 puparia per g). 'Legacy', 'Biloxi', and 'Spring High' were least susceptible to infestation, producing only 0.20-0.25 oriental fruit fly puparia per g of fruit. For Mediterranean fruit fly, 'Blue Crisp' produced 0.50 puparia per g of fruit, whereas 'Sharpblue' produced only 0.03 puparia per g of fruit. Blueberry was a marginal host for melon fly. This information will aid in development of pest management recommendations for blueberry cultivars as planting of low-chill cultivars expands to areas with subtropical and tropical fruit flies. Planting of fruit fly resistant cultivars may result in lower infestation levels and less crop loss.

  7. Expression Profiling and Structural Characterization of MicroRNAs in Adipose Tissues of Hibernating Ground Squirrels

    Directory of Open Access Journals (Sweden)

    Cheng-Wei Wu

    2014-12-01

    Full Text Available MicroRNAs (miRNAs are small non-coding RNAs that are important in regulating metabolic stress. In this study, we determined the expression and structural characteristics of 20 miRNAs in brown (BAT and white adipose tissue (WAT during torpor in thirteen-lined ground squirrels. Using a modified stem-loop technique, we found that during torpor, expression of six miRNAs including let-7a, let-7b, miR-107, miR-150, miR-222 and miR-31 was significantly downregulated in WAT (P < 0.05, which was 16%–54% of euthermic non-torpid control squirrels, whereas expression of three miRNAs including miR-143, miR-200a and miR-519d was found to be upregulated by 1.32–2.34-fold. Similarly, expression of more miRNAs was downregulated in BAT during torpor. We detected reduced expression of 6 miRNAs including miR-103a, miR-107, miR-125b, miR-21, miR-221 and miR-31 (48%–70% of control, while only expression of miR-138 was significantly upregulated (2.91 ± 0.8-fold of the control, P < 0.05. Interestingly, miRNAs found to be downregulated in WAT during torpor were similar to those dysregulated in obese humans for increased adipogenesis, whereas miRNAs with altered expression in BAT during torpor were linked to mitochondrial β-oxidation. miRPath target prediction analysis showed that miRNAs downregulated in both WAT and BAT were associated with the regulation of mitogen-activated protein kinase (MAPK signaling, while the miRNAs upregulated in WAT were linked to transforming growth factor β (TGFβ signaling. Compared to mouse sequences, no unique nucleotide substitutions within the stem-loop region were discovered for the associated pre-miRNAs for the miRNAs used in this study, suggesting no structure-influenced changes in pre-miRNA processing efficiency in the squirrel. As well, the expression of miRNA processing enzyme Dicer remained unchanged in both tissues during torpor. Overall, our findings suggest that changes of miRNA expression in adipose tissues may

  8. Expression Profiling and Structural Characterization of MicroRNAs in Adipose Tissues of Hibernating Ground Squirrels

    Institute of Scientific and Technical Information of China (English)

    Cheng-Wei Wu; Kyle K. Biggar; Kenneth B. Storey

    2014-01-01

    MicroRNAs (miRNAs) are small non-coding RNAs that are important in regulating metabolic stress. In this study, we determined the expression and structural characteristics of 20 miRNAs in brown (BAT) and white adipose tissue (WAT) during torpor in thirteen-lined ground squirrels. Using a modified stem-loop technique, we found that during torpor, expression of six miRNAs including let-7a, let-7b, miR-107, miR-150, miR-222 and miR-31 was significantly downregulated in WAT (P < 0.05), which was 16%–54% of euthermic non-torpid control squirrels, whereas expression of three miRNAs including miR-143, miR-200a and miR-519d was found to be upregulated by 1.32–2.34-fold. Similarly, expression of more miRNAs was downregulated in BAT during torpor. We detected reduced expression of 6 miRNAs including miR-103a, miR- 107, miR-125b, miR-21, miR-221 and miR-31 (48%–70% of control), while only expression of miR-138 was significantly upregulated (2.91 ± 0.8-fold of the control, P <0.05). Interestingly, miRNAs found to be downregulated in WAT during torpor were similar to those dysregulated in obese humans for increased adipogenesis, whereas miRNAs with altered expression in BAT during torpor were linked to mitochondrial b-oxidation. miRPath target prediction analysis showed that miRNAs downregulated in both WAT and BAT were associated with the regulation of mitogen- activated protein kinase (MAPK) signaling, while the miRNAs upregulated in WAT were linked to transforming growth factor b (TGFb) signaling. Compared to mouse sequences, no unique nucleotide substitutions within the stem-loop region were discovered for the associated pre-miRNAs for the miRNAs used in this study, suggesting no structure-influenced changes in pre-miRNA processing efficiency in the squirrel. As well, the expression of miRNA processing enzyme Dicer remained unchanged in both tissues during torpor. Overall, our findings suggest that changes of miRNA expression in adipose tissues may be linked to

  9. Fruit Flies Help Human Sleep Research

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues Fruit Flies Help Human Sleep Research Past Issues / Summer 2007 ... courtesy of NIGMS Neuroscientist Chiara Cirelli uses experimental fruit flies to study sleep. Although it may be tough ...

  10. Molecular cloning of pituitary glycoprotein alpha-subunit and follicle stimulating hormone and chorionic gonadotropin beta-subunits from New World squirrel monkey and owl monkey.

    Science.gov (United States)

    Scammell, Jonathan G; Funkhouser, Jane D; Moyer, Felricia S; Gibson, Susan V; Willis, Donna L

    2008-02-01

    The goal of this study was to characterize the gonadotropins expressed in pituitary glands of the New World squirrel monkey (Saimiri sp.) and owl monkey (Aotus sp.). The various subunits were amplified from total RNA from squirrel monkey and owl monkey pituitary glands by reverse transcription-polymerase chain reaction and the deduced amino acid sequences compared to those of other species. Mature squirrel monkey and owl monkey glycoprotein hormone alpha-polypeptides (96 amino acids in length) were determined to be 80% homologous to the human sequence. The sequences of mature beta subunits of follicle stimulating hormone (FSHbeta) from squirrel monkey and owl monkey (111 amino acids in length) are 92% homologous to human FSHbeta. New World primate glycoprotein hormone alpha-polypeptides and FSHbeta subunits showed conservation of all cysteine residues and consensus N-linked glycosylation sites. Attempts to amplify the beta-subunit of luteinizing hormone from squirrel monkey and owl monkey pituitary glands were unsuccessful. Rather, the beta-subunit of chorionic gonadotropin (CG) was amplified from pituitaries of both New World primates. Squirrel monkey and owl monkey CGbeta are 143 and 144 amino acids in length and 77% homologous with human CGbeta. The greatest divergence is in the C terminus, where all four sites for O-linked glycosylation in human CGbeta, responsible for delayed metabolic clearance, are predicted to be absent in New World primate CGbetas. It is likely that CG secreted from pituitary of New World primates exhibits a relatively short half-life compared to human CG.

  11. The Spider and the Fly

    Science.gov (United States)

    Mellinger, Keith E.; Viglione, Raymond

    2012-01-01

    The Spider and the Fly puzzle, originally attributed to the great puzzler Henry Ernest Dudeney, and now over 100 years old, asks for the shortest path between two points on a particular square prism. We explore a generalization, find that the original solution only holds in certain cases, and suggest how this discovery might be used in the…

  12. Electrodialytic treatment of fly ash

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Pedersen, Anne Juul; Kirkelund, Gunvor Marie

    Heavy metals are removed from the fly ashes by an electrodialytic treatment with the aim of up-grading the ashes for reuse in stead of disposal in landfill.A great potential for upgrading of bio- and waste incineration ashes by electrodialytic treatment exists. In the future, the applicability...

  13. DURABILITY OF HARDENED FLY ASH PASTE

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The mechanical properties and durability ( mainly frost-resistance and carbonation resistance ) of fly ash-CaO-CaSO4 .2H2O hardened paste are studied. The relationship among durability of harden ed fly ash paste, the quantity and distribution of hydrates and the initial p aste texture of hardened fly ash paste is presented.

  14. Louse flies on birds of Baja California.

    Science.gov (United States)

    Tella, J L; Rodríguez-Estrella, R; Blanco, G

    2000-01-01

    Louse flies were collected from 401 birds of 32 species captured in autumn of 1996 in Baja California Sur (Mexico). Only one louse fly species (Microlynchia pusilla) was found. It occurred in four of the 164 common ground doves (Columbina passerina) collected. This is a new a host species for this louse fly.

  15. Flies and Campylobacter infection of broiler flocks

    DEFF Research Database (Denmark)

    Hald, Birthe; Skovgård, Henrik; Bang, Dang Duong

    2004-01-01

    A total of 8.2% of flies caught outside a broiler house in Denmark had the potential to transmit Campylobacter jejuni to chickens, and hundreds of flies per day passed through the ventilation system into the broiler house. Our study suggests that flies may be an important source of Campylobacter...

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

    OpenAIRE

    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 extrageni...

  17. Molecular characterization of major histocompatibility complex class 1 (MHC-I) from squirrel monkeys (Saimiri sciureus).

    Science.gov (United States)

    Pascalis, Hervé; Heraud, Jean-Michel; Fendel, Rolf; Lavergne, Anne; Kazanji, Mirdad

    2003-12-01

    Little is known about the major histocompatibility complex (MHC) class 1 in squirrel monkeys ( Saimiri sciureus). We cloned, sequenced and characterized two alleles and the cDNA of the coding region of MHC class 1 in these New World monkeys. Phylogenetic analyses showed that these sequences are related to HLA class 1 genes ( HLA-A and HLA-G). The structure and organization of one of the two identified clones was similar to that of a class 1 MHC gene ( HLA-A2). All the exon/intron splice acceptor/donor sites are conserved and their locations correspond to the HLA-A2 gene. The sequences of the newly described cDNAs reveal that they code for the characteristic class 1 MHC proteins, with all the features thought necessary for cell surface expression. Typical sequences for the leader peptide, alpha(1), alpha(2), alpha(3), transmembrane and cytoplasmic domains were found.

  18. Parameters estimation of squirrel-cage induction motors using ANN and ANFIS

    Directory of Open Access Journals (Sweden)

    Mehdi Ahmadi Jirdehi

    2016-03-01

    Full Text Available In the transient behavior analysis of a squirrel-cage induction motor, the parameters of the single-cage and double-cage models are studied. These parameters are usually hard to obtain. This paper presents two new methods to predict the induction motor parameters in the single-cage and double-cage models based on artificial neural network (ANN and adaptive neuro-fuzzy inference system (ANFIS. For this purpose, the experimental data (manufacturer data of 20 induction motors with the different power are used. The experimental data are including of the starting torque and current, maximum torque, full load sleep, efficiency, rated active power and reactive power. The obtained results from the proposed ANN and ANFIS models are compared with each other and with the experimental data, which show a good agreement between the predicted values and the experimental data. But the proposed ANFIS model is more accurate than the proposed ANN model.

  19. Energetic costs of the winter arboreal microclimate: The gray squirrel in a tree

    Science.gov (United States)

    Byman, D.; Hay, D. B.; Bakken, G. S.

    1988-06-01

    Heated taxidermic mounts of the gray squirrel were used to analyze the thermal environment of a small arboreal endotherm. Changes in the standard operative temperature ( T es) calculated from the temperatures of heated and unheated mounts agreed well with the power consumption ( M-E) of mounts on the ground and on the wind-ward side of a 48-cm diameter tree trunk. As wind speed ( u) rose and sky solar radiation ( Q r) decreased, the windward side of the tree trunk became an increasingly more stressful thermal environment than the leeward side of the trunk or the ground, producing M-E differences of more than 30%. Although the M-E of a ground mount and a limb mount 4 m in the air are dependent on Q ras well as u, the ratio of the two value of M-E is independent of Q r, poorly predicted by u and well predicted by u 1/2.

  20. Demography of a population collapse: the Northern Idaho ground squirrel (Spermophilus brunneus brunneus)

    Science.gov (United States)

    Sherman, P.W.; Runge, M.C.

    2002-01-01

    We studied the demography of a population of Northern Idaho ground squirrels (Spermophilus brunneus brunneus) in Adams Co., Idaho. The population was completely censused yearly from 1987 to 1999, during which time it declined from 272 to 10 animals. The finite population growth rate, based on a Leslie matrix model of average life-history parameters, was only 0.72 (i.e., significantly sensitive to proportional changes in juvenile female survival than to any other single life-history parameter. Comparisons with self-sustaining populations of closely related ground squirrel species revealed that juvenile survival and breeding rates of yearling females were anomalously low. We believe that the ultimate cause of the population's collapse was inadequacy of food resources, particularly seeds, due to drying of the habitat and changes in plant species composition, likely the result of fire suppression and grazing. No 'rescue' by immigration occurred, probably because S. b. brunneus seldom disperse long distances and fire suppression has allowed conifers to encroach on inhabited meadows, shrinking them and closing dispersal routes. The proximate cause of the population's collapse was mortality of older breeding females, which reduced the mean age of breeders. Younger females had lower average pregnancy rates and litter sizes. To place our results in context we developed a new, general classification of anthropogenic population declines, based on whether they are caused by changes in the means of the life-history parameters (blatant disturbances), their variances (inappropriate variations), or the correlations among them (evolutionary traps). Many S. b. brunneus populations have disappeared in recent years, apparently due to blatant disturbances, especially loss of habitat and changes in food-plant composition, resulting in inadequate prehibernation nutrition and starvation overwinter. In addition, our study population may have been caught in an evolutionary trap, because the

  1. Photocurrents of cone photoreceptors of the golden-mantled ground squirrel.

    Science.gov (United States)

    Kraft, T W

    1988-10-01

    1. Visual transduction in photoreceptors of the ground squirrel, Citellus lateralis, was studied by recording membrane current from individual cones in small pieces of retina. 2. Brief flashes of light produced transient reductions of the dark current; saturating response amplitudes were up to 67 pA. A flash strength of about 11,000 photons microns-2 at lambda max was required to give a half-saturating response. The stimulus-response relation was well fitted by an exponential saturation curve. Responses below 20% of maximum behaved linearly. 3. The response to a dim flash in most cells had a time to peak of 20-30 ms and resembled the impulse response of a series of five low-pass filters. 4. The variance of the dim-flash response amplitude put an upper limit of 80 fA on the size of the single photon response. Estimates based on the effective collecting area suggest the single photon response to be of the order of 10 fA. 5. Flash responses of squirrel cones usually lacked the undershoot observed in primate cones, although in about 1/3 of the cells a small undershoot developed during recording. 6. Background lights slightly shortened the time to peak of the flash response and reduced the integration time. 7. Spectral sensitivity measurements showed two classes of cones with peak sensitivities at about 520 and 435 nm. Rod sensitivity peaked near 500 nm. Spectral univariance was obeyed by all three classes of cells. 8. The shapes of the spectral sensitivity curves of the rod and both types of cones were similar to each other when plotted on a log wave number scale, but differed significantly from similar plots of monkey and human cone spectra. 9. The kinetics and sensitivity of flash responses of the blue- and green-sensitive cones were indistinguishable.

  2. Phylogeny of mitochondrial DNA clones in tassel-eared squirrels Sciurus aberti.

    Science.gov (United States)

    Wettstein, P J; Lager, P; Jin, L; States, J; Lamb, T; Chakraborty, R

    1994-12-01

    The tassel-eared squirrel, Sciurus aberti, includes six subspecies which occupy restrictive and apparently identical habitats in Ponderosa pine forests in the south-western United States and Mexico; the strict habitat requirement of this species is based on dietary requirements which are only fulfilled in these forests. To examine evolutionary relationships among certain subspecies of S. aberti, we obtained estimates of nucleotide diversity within subspecies as well as nucleotide divergence between subspecies using mitochondrial DNA (mtDNA) analysis. Restriction site polymorphisms were identified in samples of the four US subspecies: S. a. aberti (Abert), S. a. kaibabensis (Kaibab), S. a. ferreus (Ferreus), and S. a. chuscensis (Chuska) Fourteen mtDNA clones were resolved that were, with one exception, uniquely subspecific. Dendrograms constructed by neighbour-joining and maximum parsimony methods revealed two major assemblages: (1) an Abert/Kaibab group; and (2) a Ferreus/Chuska group. The Abert vs. Ferreus clones exhibited the greatest net nucleotide divergence, with a lineage separation estimate approximating 572,000 years ago assuming a nucleotide substitution rate of 7.15 x 10(-9)/year/site. Five out of ten Chuska squirrels shared a clone with one Abert sample; the relative sizes of these two populations and their respective ranges as well as their close proximity support the proposal for relatively recent intermixing of Abert and Chuska populations resulting in what appears to be Abert-->Chuska migration. Nucleotide diversity within subspecies ranked as Kaibab Kaibab, Ferreus and Aberti samples corresponds to the range size of the respective subspecies.

  3. Finite element modelling of squirrel, guinea pig and rat skulls: using geometric morphometrics to assess sensitivity.

    Science.gov (United States)

    Cox, P G; Fagan, M J; Rayfield, E J; Jeffery, N

    2011-12-01

    Rodents are defined by a uniquely specialized dentition and a highly complex arrangement of jaw-closing muscles. Finite element analysis (FEA) is an ideal technique to investigate the biomechanical implications of these specializations, but it is essential to understand fully the degree of influence of the different input parameters of the FE model to have confidence in the model's predictions. This study evaluates the sensitivity of FE models of rodent crania to elastic properties of the materials, loading direction, and the location and orientation of the models' constraints. Three FE models were constructed of squirrel, guinea pig and rat skulls. Each was loaded to simulate biting on the incisors, and the first and the third molars, with the angle of the incisal bite varied over a range of 45°. The Young's moduli of the bone and teeth components were varied between limits defined by findings from our own and previously published tests of material properties. Geometric morphometrics (GMM) was used to analyse the resulting skull deformations. Bone stiffness was found to have the strongest influence on the results in all three rodents, followed by bite position, and then bite angle and muscle orientation. Tooth material properties were shown to have little effect on the deformation of the skull. The effect of bite position varied between species, with the mesiodistal position of the biting tooth being most important in squirrels and guinea pigs, whereas bilateral vs. unilateral biting had the greatest influence in rats. A GMM analysis of isolated incisor deformations showed that, for all rodents, bite angle is the most important parameter, followed by elastic properties of the tooth. The results here elucidate which input parameters are most important when defining the FE models, but also provide interesting glimpses of the biomechanical differences between the three skulls, which will be fully explored in future publications. © 2011 The Authors. Journal of

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

    Science.gov (United States)

    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

  5. FliO regulation of FliP in the formation of the Salmonella enterica flagellum.

    Directory of Open Access Journals (Sweden)

    Clive S Barker

    2010-09-01

    Full Text Available 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.

  6. Aerodynamics of the Smallest Flying Insects

    CERN Document Server

    Miller, Laura A; Hedrick, Ty; Robinson, Alice; Santhanakrishnan, Arvind; Lowe, Audrey

    2011-01-01

    We present fluid dynamics videos of the flight of some of the smallest insects including the jewel wasp, \\textit{Ampulex compressa}, and thrips, \\textit{Thysanoptera} spp. The fruit fly, \\textit{Drosophila melanogaster}, is large in comparison to these insects. While the fruit fly flies at $Re \\approx 120$, the jewel wasp flies at $Re \\approx 60$, and thrips flies at $Re \\approx 10$. Differences in the general structures of the wakes generated by each species are observed. The differences in the wakes correspond to changes in the ratio of lift forces (vertical component) to drag forces (horizontal component) generated.

  7. Behavior and foraging technique of the Ingram's squirrel Guerlinguetus ingrami (Sciuridae: Rodentia in an Araucaria moist forest fragment

    Directory of Open Access Journals (Sweden)

    Calebe Pereira Mendes

    2014-06-01

    Full Text Available This work describes the foraging techniques, body positions and behavior of free-ranging Ingram's squirrel Guerlinguetus ingrami Thomas, 1901 in a region of the Araucaria moist forest, in the Atlantic Forest of southern Brazil. The animals were observed using the "all occurrence sampling" method with the aid of binoculars and a digital camcorder. All behaviors were described in diagrams and an ethogram. We recorded five basic body positions, 24 behaviors, two food choices, and three feeding strategies utilized to open fruits of Syagrus romanzoffiana (Cham., the main food source of Ingram's squirrels. We also observed a variance in the animals' stance, which is possibly influenced by predation risk, and discuss the causes of some behaviors.

  8. Binocular interactions underlying the classic optomotor responses of flying flies

    Directory of Open Access Journals (Sweden)

    Brian J Duistermars

    2012-02-01

    Full Text Available In response to imposed course deviations, the fast optomotor reactions of animals reduce motion blur and facilitate the maintenance of stable body posture. In flies, the monocular front-to-back (progressive and back-to-front (regressive visual motion components generated by horizontal rotation are selectively encoded, respectively, by homo and heterolateral motion sensitive circuits in the third optic ganglion, the lobula plate. To investigate the strength of such inter-ocular interactions and their role in compensatory sensory-motor transformations, we utilize a virtual reality flight simulator to record optomotor reactions by tethered flying flies in response to imposed binocular and monocular visual rotation. With stimulus parameters generating large contrast insensitive optomotor responses to binocular rotation, we find that responses to monocular progressive motion are larger than those to panoramic rotation but contrast sensitive. Conversely, responses to monocular regressive motion are slower than those to rotation and peak at the lowest tested contrast. Together our results suggest that contrast insensitive optomotor responses to binocular rotation result from the dynamic interplay of contralateral inhibitory as well as excitatory circuit interactions and serve to maintain a stable optomotor equilibrium across a range of visual contrasts.

  9. Influenza Alone and in Sequence with Pneumonia Due to ’Streptococcus pneumoniae’ in the Squirrel Monkey

    Science.gov (United States)

    1975-03-28

    rights reserved. . . . . t Influenza Alone and In Sequence with Pneumonia Due to-, Streptococcus pneumoniae in the Squirrel Monkey VI / !.llendt, G.G...rhesus drome of sequential respiratory infections. monkeys with the virus alone or in sequence with Streptococcus pneumoniae I1 l. Since that report...were also BC 0 0 observed in the glomeruli of the kidney. S 0 1027 S. pneumoniae-induced pathology. The results Streptococcus pneumoniae obtained in

  10. Phenotypic and functional characterization of lymphocytes from different age groups of Bolivian squirrel monkeys (Saimiri boliviensis boliviensis.

    Directory of Open Access Journals (Sweden)

    Pramod N Nehete

    Full Text Available Due to many physiological and genetic characteristic similarities to humans, squirrel monkeys provide an ideal animal model specifically for studying malaria, and transmissible spongiform encephalopathies (Creutzfeldt-Jacob disease. While squirrel monkeys three years and older are generally considered adult subjects suitable for use in medical research studies, little is known about the functional properties of lymphocytes in relation to the age of these animals, which could significantly impact the quality and quantity of innate and adaptive immune responses. In this study, we investigated differences in the phenotype and function of lymphocytes subsets of young (3-4 years, adult (8-10 years and aged (16-19 years squirrel monkeys. In general, animals in all three age groups exhibited comparable numbers of different lymphocyte subsets except for CD20+ B cells that were significantly lower in aged relative to young animals and T cells subsets expressing both CD4 and CD8 (double positive were significantly higher in aged relative to young animals. With increasing age, phenotypic differences in central and effector memory T cells subsets were observed, that were more pronounced for the CD8+ T cells. Despite equal proportions of CD3+ T cells among the three age groups, responses of peripheral blood mononuclear cells to T cell mitogens PHA and Con A showed lower IFN-γ producing cells in the aged group than that in the young group. Furthermore, aged animals showed significantly higher plasma levels of inflammatory cytokines IL-6, IFN-γ, TNF-α, IL-10 and IL-12. These findings suggest that while the squirrel monkeys in general share phenotypic and functional similarities of lymphocyte subsets with humans in relation to age, specific differences exist in immune function of lymphocytes between young and old animals that could potentially impact experimental outcomes for which the measurement of immunologic endpoints are critical.

  11. The song remains the same: Juvenile Richardson's ground squirrels do not respond differentially to mother's or colony member's alarm calls

    Institute of Scientific and Technical Information of China (English)

    James F.HARE; Kurtis J.WARKENTIN

    2012-01-01

    Alarm calls are emitted by Richardson's ground squirrels Urocitellus richardsonii in response to avian and terrestrial predators.Conspecifics detecting these calls respond with increased vigilance,promoting predator detection and evasion,but in doing so,lose time from foraging.That loss can be minimized if alarm call recipients discriminate among signalers,and weight their response accordingly.For juvenile ground squirrels,we predicted that the trade-off between foraging and vigilance could be optimized via selective response to alarm calls emitted by their own dam,and/or neighboring colony members over calls broadcast by less familiar conspecifics.Alarm calls of adult female Richardson's ground squirrels were elicited in the field using a predator model and recorded on digital audio tape.Free-living focal juveniles were subjected to playbacks of a call of their mother,and on a separate occasion a call from either another adult female from their own colony,or an adult female from another colony.Neither immediate postural responses and escape behavior,nor the duration of vigilance manifested by juveniles differed with exposure to alarm calls of the three adult female signaler types.Thus,juveniles did not respond preferentially to alarm calls emitted by their mothers or colony members,likely reflecting the high cost of ignoring alarm signals where receivers have had limited opportunity to establish past signaler reliability.

  12. A comparison of positive reinforcement training techniques in owl and squirrel monkeys: time required to train to reliability.

    Science.gov (United States)

    Rogge, Jessica; Sherenco, Katrina; Malling, Rachel; Thiele, Erica; Lambeth, Susan; Schapiro, Steve; Williams, Lawrence

    2013-01-01

    Positive reinforcement training (PRT) techniques enhance the psychological well being of nonhuman primates by increasing the animal's control over his or her environment and desensitizing the animal to stressful stimuli. However, the literature on PRT in neotropical primates is limited. Here PRT data from owl monkeys and squirrel monkeys are presented, including the length of time to train subjects to target, present hand, and present foot, important responses that can be used to aid in health inspection and treatment. A high percentage of the squirrel and owl monkeys were successfully trained on target and present hand. Present foot, a less natural response, was harder to train and maintain. Although squirrel monkeys did learn to target significantly faster than owl monkeys, the 2 genera did not differ on time to train on subsequent behavior. These data demonstrate that although owl monkeys may require slightly more time to acclimate to a PRT program, it is still possible to establish a PRT program with neotropical primates, and once animals have been introduced to the program, they can learn new responses in a relatively few short sessions.

  13. Polymorphism in Trypomastigotes of Trypanosoma (Megatrypanum minasense in the blood of experimentally infected squirrel monkey and marmosets

    Directory of Open Access Journals (Sweden)

    Mariangela Ziccardi

    1999-09-01

    Full Text Available Experimental infections by Trypanosoma (Megatrypanum minasense were performed in primates - Saimiri sciureus and Callithrix penicillata - with the objective of searching for morphological variations of the blood trypomastigotes with respect to hosts and time of infection. We carried out morphological and morphometric analysis of blood trypomastigotes. Illustrations are given. Both the squirrel monkey and marmoset became infected after the injection of blood trypomastigotes of T. minasense , although the parasitaemia were briefer in the squirrel monkey. The parasites detected in the later host were narrower and shorter than those found in the inoculated marmoset. In the marmoset, the blood stream parasites derived from culture metacyclic trypomastigotes were considerably smaller than those derived from the inoculation of infected blood. Stronger evidence of polymorphism was found when, at the same time of infection, the blood trypomastigotes found in squirrel monkey had smaller length, body width and the distance from posterior end of the body to the kinetoplast almost four times smaller than the parasite found in the marmoset. Therefore, conflicting results on morphology and morphometry of T. minasense obtained by previous investigators could be due to polymorphism.

  14. Practical Aspects of Broken Rotor Bars Detection in PWM Voltage-Source-Inverter-Fed Squirrel-Cage Induction Motors

    Directory of Open Access Journals (Sweden)

    Hong-yu Zhu

    2013-01-01

    Full Text Available Broken rotor bars fault detection in inverter-fed squirrel cage induction motors is still as difficult as the dynamics introduced by the control system or the dynamically changing excitation (stator frequency. This paper introduces a novel fault diagnosis techniques using motor current signature analysis (MCSA to solve the problems. Switching function concept and frequency modulation theory are firstly used to model fault current signal. The competency of the amplitude of the sideband components at frequencies (1±2sfs as indices for broken bars recognition is subsequently studied in the controlled motor via open-loop constant voltage/frequency control method. The proposed techniques are composed of five modules of anti-aliasing signal acquisition, optimal-slip-estimation based on torque-speed characteristic curve of squirrel cage motor with different load types, fault characteristic frequency determination, nonparametric spectrum estimation, and fault identification for achieving MCSA efficiently. Experimental and simulation results obtained on 3 kW three-phase squirrel-cage induction motors show that the model and the proposed techniques are effective and accurate.

  15. Sexual size dimorphism in ground squirrels (Rodentia: Sciuridae: Marmotini) does not correlate with body size and sociality.

    Science.gov (United States)

    Matějů, Jan; Kratochvíl, Lukáš

    2013-05-14

    Sexual size dimorphism (SSD) is a widespread phenomenon in animals including mammals. It has been demonstrated that across species, the direction and magnitude of sexual dimorphism in body size often corresponds to social systems. Moreover, many animal lineages conform to "Rensch's rule", which states that male-biased SSD increases with body size. We tested whether considerable differences in sociality and large variation in body size were connected with the evolution of SSD in the structural body size of ground squirrels, an otherwise ecologically relatively homogenous group of terrestrial rodents. We found the general trend of male-biased SSD in ground squirrels, however, male size increases nearly perfectly isometrically with female size among species and sociality does not explain departures from this relationship. Species with different sociality grades significantly differ in body size, with the most social species tending to be the largest. We suggest that lack of conformity with Rensch´s rule in ground squirrels may be attributed to their low variation in SSD, and briefly discuss three potential causes of small magnitude of SSD in the structural size in rodents: low selection on SSD in structural dimensions, ontogenetic and genetic constraints and the existence of ecological/selection factors preventing the evolution of extensive SSD.

  16. Geopolymer Mortar with Fly Ash

    Directory of Open Access Journals (Sweden)

    Saloma

    2016-01-01

    Full Text Available The cement industry accounts for about 7% of all CO2 emissions caused by humans. Therefore, it is necessary to find another material in order to support sustainable material. An alternative way is replacing cement material with alternative material as fly ash. Fly ash as binder need to be added alkaline activator in the form of sodium silicate (Na2SiO3 or potassium silicate (K2SiO3 and sodium hydroxide (NaOH or potassium hydroxide (KOH. The purpose of this research is to analyze the effect of activator liquid concentration on geopolymer mortar properties and to know the value of compressive strength. Molarity variation of NaOH are 8, 12, 14, and 16 M with ratio of Na2SiO3/NaOH = 1.0. Ratio of sand/fly ash = 2.75 and ratio of activator/fly ash = 0.8. The cube-shaped specimen 50 × 50 × 50 mm is cured by steam curing with a temperature of 60°C for 48 hours. The experimental result of fresh mortar reported that the molarity of NaOH affect the slump flow and setting time, higher of NaOH produces the smaller value of slump and the faster time of setting. The experimental of density results reported that the increase of specific gravity when the molarity of NaOH increased. The experimental results of the compressive strength are showed that the maximum compressive strength of geopolymer mortar 14 M is 10.06 MPa and the lowest compressive strength produced by geopolymer mortar 8 M is 3.95 MPa. Testing the compressive strength of geopolymer mortar 16 M produces compressive strength lower than 14 M geopolymer mortar is 9.16 MPa.

  17. "Fly me to the moon"

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ China's first lunar probe Chang'e-I, named after a mythical Chinese goddess who, according to legend, made her home on the moon, blasted off on 24 October from the Xichang Satellite Launch Center in the southwestern province of Sichuan. In addition to making the dream cherished by Chinese people to fly to the moon come true, it is the first step into China's ambitious threestage moon mission, marking a new milestone in the country's space exploration history.

  18. Notes on flying and dying.

    Science.gov (United States)

    Meyer, B C

    1983-07-01

    Focused on selected details in the lives and creative works of Samuel Johnson, Edgar Allan Poe, and Houdini, this paper explores a seeming antinomy between claustrophobic annihilation and aviation. At first glance the latter appears as an antidote to the threat of entrapment and death. On a deeper level the distinction fades as the impression arises that in the examples cited, flying may represent an unconscious expression of a wish for death and ultimate reunion.

  19. Identifying glass compositions in fly ash

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    Katherine eAughenbaugh

    2016-01-01

    Full Text Available In this study, four Class F fly ashes were studied with a scanning electron microscope; the glassy phases were identified and their compositions quantified using point compositional analysis with k-means clustering and multispectral image analysis. The results showed that while the bulk oxide contents of the fly ashes were different, the four fly ashes had somewhat similar glassy phase compositions. Aluminosilicate glasses (AS, calcium aluminosilicate glasses (CAS, a mixed glass, and, in one case, a high iron glass were identified in the fly ashes. Quartz and iron crystalline phases were identified in each fly ash as well. The compositions of the three main glasses identified, AS, CAS, and mixed glass, were relatively similar in each ash. The amounts of each glass were varied by fly ash, with the highest calcium fly ash containing the most of calcium-containing glass. Some of the glasses were identified as intermixed in individual particles, particularly the calcium-containing glasses. Finally, the smallest particles in the fly ashes, with the most surface area available to react in alkaline solution, such as when mixed with portland cement or in alkali-activated fly ash, were not different in composition than the large particles, with each of the glasses represented. The method used in the study may be applied to a fly ash of interest for use as a cementing material in order to understand its potential for reactivity.

  20. DNA analysis of a 30,000-year-old Urocitellus glacialis from northeastern Siberia reveals phylogenetic relationships between ancient and present-day arctic ground squirrels

    Science.gov (United States)

    Faerman, Marina; Bar-Gal, Gila Kahila; Boaretto, Elisabetta; Boeskorov, Gennady G.; Dokuchaev, Nikolai E.; Ermakov, Oleg A.; Golenishchev, Fedor N.; Gubin, Stanislav V.; Mintz, Eugenia; Simonov, Evgeniy; Surin, Vadim L.; Titov, Sergei V.; Zanina, Oksana G.; Formozov, Nikolai A.

    2017-01-01

    In contrast to the abundant fossil record of arctic ground squirrels, Urocitellus parryii, from eastern Beringia, only a limited number of fossils is known from its western part. In 1946, unnamed GULAG prisoners discovered a nest with three mummified carcasses of arctic ground squirrels in the permafrost sediments of the El’ga river, Yakutia, Russia, that were later attributed to a new species, Citellus (Urocitellus) glacialis Vinogr. To verify this assignment and to explore phylogenetic relationships between ancient and present-day arctic ground squirrels, we performed 14C dating and ancient DNA analyses of one of the El’ga mummies and four contemporaneous fossils from Duvanny Yar, northeastern Yakutia. Phylogenetic reconstructions, based on complete cytochrome b gene sequences of five Late Pleistocene arctic ground squirrels and those of modern U. parryii from 21 locations across western Beringia, provided no support for earlier proposals that ancient arctic ground squirrels from Siberia constitute a distinct species. In fact, we observed genetic continuity of the glacialis mitochondrial DNA lineage in modern U. parryii of the Kamchatka peninsula. When viewed in a broader geographic perspective, our findings provide new insights into the genetic history of U. parryii in Late Pleistocene Beringia. PMID:28205612

  1. Continuous infusion of propofol or intermittent bolus of tiletamine-zolazepam in squirrel monkeys (Saimiri sciureus).

    Science.gov (United States)

    Galante, Rafaela; Muniz, José A P C; Castro, Paulo H G; Gris, Vanessa N; Carvalho, Elizabeth R; Amora, Dorli S; Vilani, Ricardo G D'O C

    2014-09-01

    To investigate an infusion of propofol for anesthesia in comparison to tiletamine-zolazepam anesthesia, evaluating physiological variables and recovery in squirrel monkeys. Prospective non-blinded randomized study. Eight healthy squirrel monkeys (Saimiri sciureus), aged 3 years and weighing 0.340-0.695 kg. Premedication was intramuscular midazolam (0.5 mg) and meperidine (4 mg). Anesthesia was induced with intravenous (IV) propofol (4 mg kg(-1)  minute(-1) ) and maintained with propofol starting at 0.4 mg kg(-1)  minute(-1) (PRO, n = 4) or IV tiletamine-zolazepam (5 mg kg(-1) ) and maintained with supplementary doses of TZ (TZ, n = 4). Cardiopulmonary variables were measured continuously. Arterial blood gases and lactate concentration were measured at the end of anesthesia. Quality and times of recovery were determined. Repeatedly measured data for significant differences were tested between groups with t-test and within groups by anova. Median time for induction of anesthesia in PRO was 180 seconds. Mean maintenance infusion rate of propofol was 0.43 ± 0.05 mg kg(-1)  minute(-1) , varying during the 1 hour period. One monkey died after administration of TZ; others required 1, 4, or 8 supplemental doses. Cardiopulmonary variables were similar between groups, but hypotension was recorded. Recovery times to ventral recumbency in PRO (32 ± 17 minutes) and TZ (84 ± 11 minutes) and normal ambulation in PRO (58 ± 22 minutes) and TZ (358 ± 109minutes) were significantly different (p < 0.05). Recovery quality was superior in PRO, with less ataxia and fewer unsuccessful attempts to stand. Lactate concentration was not different between treatments. Cardiopulmonary variables were similar between protocols, aside from the higher incidence of hypotension in PRO, indicating that further studies with a larger number of animals are required. Compared to tiletamine-zolazepam, propofol anesthesia provided faster and superior anesthetic

  2. Possibilities of utilizing power plant fly ashes

    Directory of Open Access Journals (Sweden)

    Mezencevová Andrea

    2003-09-01

    Full Text Available The burning of fossil fuels in industrial power stations plays a significant role in the production of thermal and electrical energy. Modern thermal power plants are producing large amounts of solid waste, mainly fly ashes. The disposal of power plant waste is a large environmental problem at the present time. In this paper, possibilities of utilization of power plant fly ashes in industry, especially in civil engineering, are presented. The fly ash is a heterogeneous material with various physical, chemical and mineralogical properties, depending on the mineralogical composition of burned coal and on the used combustion technology. The utilization of fly ashes is determined of their properties. The fineness, specific surface area, particle shape, density, hardness, freeze-thaw resistance, etc. are decisive. The building trade is a branch of industry, which employs fly ash in large quantities for several decades.The best utilization of fluid fly ashes is mainly in the production of cement and concrete, due to the excellent pozzolanic and cementitious properties of this waste. In the concrete processing, the fly ash is utilized as a replacement of the fine aggregate (fine filler or a partial replacement for cement (active admixture. In addition to economic and ecological benefits, the use of fly ash in concrete improves its workability and durability, increases compressive and flexural strength, reduces segregation, bleeding, shrinkage, heat evolution and permeability and enhances sulfate resistance of concrete.The aim of current research is to search for new technologies for the fly ash utilization. The very interesting are biotechnological methods to recovery useful components of fly ashes and unconventional methods of modification of fly ash properties such as hydrothermal zeolitization and mechanochemical modification of its properties. Mechanochemistry deals with physico - chemical transformations and chemical reactions of solids induced by

  3. Revised irradiation doses to control melon fly, Mediterranean fruit fly, and oriental fruit fly (Diptera: Tephritidae) and a generic dose for tephritid fruit flies.

    Science.gov (United States)

    Follett, Peter A; Armstrong, John W

    2004-08-01

    Currently approved irradiation quarantine treatment doses for Bactrocera cucurbitae (Coquillet), melon fly; Ceratitis capitata (Wiedemann), Mediterranean fruit fly; and Bactrocera dorsalis (Hendel), oriental fruit fly, infesting fruits and vegetables for export from Hawaii to the continental United States are 210, 225, and 250 Gy, respectively. Irradiation studies were initiated to determine whether these doses could be reduced to lower treatment costs, minimize any adverse effects on quality, and support a proposed generic irradiation dose of 150 Gy for fruit flies. Dose-response tests were conducted with late third instars of wild and laboratory strains of the three fruit fly species, both in diet and in fruit. After x-ray irradiation treatment, data were taken on adult emergence, and adult female fecundity and fertility. Melon fly was the most tolerant of the three species to irradiation, and oriental fruit fly was more tolerant than Mediterranean fruit fly. Laboratory and wild strains of each species were equally tolerant of irradiation, and larvae were more tolerant when irradiated in fruit compared with artificial diet. An irradiation dose of 150 Gy applied to 93,666 melon fly late third instars in papayas resulted in no survival to the adult stage, indicating that this dose is sufficient to provide quarantine security. Irradiation doses of 100 and 125 Gy applied to 31,920 Mediterranean fruit fly and 55,743 oriental fruit fly late third instars, respectively, also resulted in no survival to the adult stage. Results support a proposed generic irradiation quarantine treatment dose of 150 Gy for all tephritid fruit flies.

  4. Flying qualities criteria and flight control design

    Science.gov (United States)

    Berry, D. T.

    1981-01-01

    Despite the application of sophisticated design methodology, newly introduced aircraft continue to suffer from basic flying qualities deficiencies. Two recent meetings, the DOD/NASA Workshop on Highly Augmented Aircraft Criteria and the NASA Dryden Flight Research Center/Air Force Flight Test Center/AIAA Pilot Induced Oscillation Workshop, addressed this problem. An overview of these meetings is provided from the point of view of the relationship between flying qualities criteria and flight control system design. Among the items discussed are flying qualities criteria development, the role of simulation, and communication between flying qualities specialists and control system designers.

  5. Use Of Fly Iarvae In Space Agriculture

    Science.gov (United States)

    Katayama, Naomi; Mitsuhashi, Jun; Hachiya, Natumi; Miyashita, Sachiko; Hotta, Atuko

    The concept of space agriculture is full use of biological and ecological components ot drive materials recycle loop. In an ecological system, producers, consumers and decomposers are its member. At limited resources acailable for space agriculture, full use of members' function is required to avoid food shortage and catastrophe.Fly is categrized to a decomposer at its eating excreta and rotten materials. However, is it could be edible, certainly it is eaten in several food culture of the world, it functions as a converter of inedible biomass ot edible substance. This conversion enhances the efficiency of usage of resource that will be attributed to space agriculture. In this context, we examine the value of melon fly, Dacus cucurbitae, as a candidate fly species ofr human food. Nutrients in 100g of melon fly larvae were protein 12g, lipid 4.6g Fe 4.74mg, Ca 275mg, Zn 6.37mg, Mn 4.00mg. Amino acids compositon in 100g of larvae was glutamic acid 1.43g and aspartic acid 1.12g. Because of high contents of these amino acids taste of fly larva might be good. Life time of adult melon fly is one to two month, and lays more than 1,000 eggs in total during the life. Larvae hatch after one to two days, and metamorphose after 8 to 15 days to pupae. Srxual maturity is reached after 22 days the earliest from it egg. Sixteen generations could be succeeded in a year for melon fly at maximum. The rate of proliferation of fly is quite high compared to silkworm that can have 8.7 generations per year. The wide food habit of fly, compared to mulberry leaf for silkworm, is another advantage to choose fly for entomophage. Rearing technology of melon fly is well established, since large scaled production of sterile male fly has been conducted in order ot exterminate melon fly in the field. Feeding substance for melon fly larvae in production line is a mixture of wheat, bran, raw sugar, olara, beer yeast, tissue paper, and additive chemicals. A 1 kg of feed substance can be converted to

  6. What the fly's nose tells the fly's brain.

    Science.gov (United States)

    Stevens, Charles F

    2015-07-28

    The fly olfactory system has a three-layer architecture: The fly's olfactory receptor neurons send odor information to the first layer (the encoder) where this information is formatted as combinatorial odor code, one which is maximally informative, with the most informative neurons firing fastest. This first layer then sends the encoded odor information to the second layer (decoder), which consists of about 2,000 neurons that receive the odor information and "break" the code. For each odor, the amplitude of the synaptic odor input to the 2,000 second-layer neurons is approximately normally distributed across the population, which means that only a very small fraction of neurons receive a large input. Each odor, however, activates its own population of large-input neurons and so a small subset of the 2,000 neurons serves as a unique tag for the odor. Strong inhibition prevents most of the second-stage neurons from firing spikes, and therefore spikes from only the small population of large-input neurons is relayed to the third stage. This selected population provides the third stage (the user) with an odor label that can be used to direct behavior based on what odor is present.

  7. Characteristics of spanish fly ashes

    Directory of Open Access Journals (Sweden)

    de Luxán, M. P.

    1988-03-01

    Full Text Available The purpose of this study is the characterization of fly ashes produced by Spanish thermoelectric power plants, according to sampling taken in 1981 and 1982. The study takes in the following characteristics: physical characteristics (size distribution of particles, ...; chemical ones (chemical analysis...; and mineralogical ones (application of instrumental techniques of X-ray diffraction and infrared absorption spectroscopy. From a general point of view, it can be said that the samples of Spanish fly ashes are similar to those produced in other countries. The results obtained are a contribution to the knowledge of Spanish fly ashes and form part of the antecedents of investigations carried out in subsequent years.

    Este trabajo tiene por objeto la caracterización de las cenizas volantes producidas en las Centrales Termoeléctricas españolas, según un muestreo realizado entre 1981 y 1982. El estudio comprende las siguientes características: físicas (distribución del tamaño de partículas,...; químicas (análisis químico, …; y mineralógicas (aplicación de las técnicas instrumentales de difracción de rayos X y espectroscopía de absorción infrarroja. Desde un punto de vista general, se puede afirmar que las muestras de ceniza volante estudiadas son semejantes a las producidas en otros países. Los resultados obtenidos son una aportación al conocimiento de las cenizas volantes españolas y forman parte de los antecedentes de las investigaciones llevadas a cabo en años posteriores.

  8. Phylogenetic analysis of skull shape evolution in marmotine squirrels using landmarks and thin-plate splines

    Directory of Open Access Journals (Sweden)

    Donald Swiderski

    2000-06-01

    Full Text Available Abstract Several studies have shown that the recently developed techniques of geometric morphometrics are extremely powerful descriptive tools. And yet, one potential use of the resulting descriptions, phylogenetic analysis, has generally been neglected. This neglect is understandable because prominent systematists as well as prominent morphometricians have objected to the use of morphometric data in phylogenetic systematics. We agree that some methods of morphometric analysis produce results that cannot be used in phylogenetic systematics, and that some methods of incorporating morphometric results into statements about character transformation are not appropriate. However, we do not agree that these objections to specific techniques support a blanket rejection of the use of morphometric data in systematic studies. In this paper, we review the principles of phylogenetic systematics and show that they are equally applicable to qualitative descriptions of triangles and to quantitative descriptions (shape coordinates of the apex of those same shapes. Then we show how these principles would he applied to complex shapes like skulls of marmotine squirrels, and that the resulting analysis leads to legitimate hypotheses about marmotine phylogeny and the evolution of skull shape in these animals.

  9. Inverted-U shape relationship between cortisol and learning in ground squirrels.

    Science.gov (United States)

    Mateo, Jill M

    2008-05-01

    Adrenal hormones regulate glucose levels, responses to unpredictable stressors and modulate cognition. Glucocorticoids can have an inverted-U shape relationship with cognition, as very low or high levels impair, whereas moderate elevations facilitate, acquisition and retention of memories. To date these relationships have been tested with humans and rodents in laboratory settings rather than with wild animals in biologically relevant contexts. This study examined whether the elevated cortisol observed in juvenile Belding's ground squirrels (Spermophilus beldingi) at natal emergence might promote both acquisition of adaptive responses to this species' two alarm calls warning of predators and memory of the spatial configuration of mothers' territories. Both experimentally increased and decreased basal cortisol levels interfere with acquisition and retention of an association between a warning call and the appropriate response compared with naturally occurring moderately elevated cortisol. Further, decreased cortisol impairs learning of a novel, complex spatial maze. Thus in the field the brief elevation of cortisol at emergence might facilitate acquisition of spatial memory of a three-dimensional environment and responses to alarm calls during a sensitive period of learning. This novel demonstration of the inverted-U shape function in a wild animal suggests that natural selection has favored a hormonal profile facilitating rapid acquisition of important survival behaviors.

  10. Cognitive correlates of white matter growth and stress hormones in female squirrel monkey adults.

    Science.gov (United States)

    Lyons, David M; Yang, Chou; Eliez, Stephan; Reiss, Allan L; Schatzberg, Alan F

    2004-04-07

    Neurobiological studies of stress and cognitive aging seldom consider white matter despite indications that complex brain processes depend on networks and white matter interconnections. Frontal and temporal lobe white matter volumes increase throughout midlife adulthood in humans, and this aspect of aging is thought to enhance distributed brain functions. Here, we examine spatial learning and memory, neuroendocrine responses to psychological stress, and regional volumes of gray and white matter determined by magnetic resonance imaging in 31 female squirrel monkeys between the ages of 5 and 17 years. This period of lifespan development corresponds to the years 18-60 in humans. Older adults responded to stress with greater increases in plasma levels of adrenocorticotropic hormone and modest reductions in glucocorticoid feedback sensitivity relative to young adults. Learning and memory did not differ with age during the initial cognitive test sessions, but older adults more often failed to inhibit the initial learned response after subsequent spatial reversals. Impaired cognitive response inhibition correlated with the expansion of white matter volume statistically controlling for age, stress hormones, gray matter, and CSF volumes. These results indicate that instead of enhancing cognitive control during midlife adulthood, white matter volume expansion contributes to aspects of cognitive decline. Cellular and molecular research combined with brain imaging is needed to determine the basis of white matter growth in adults, elucidate its functions during lifespan development, and provide potential new targets for therapies aimed at maintaining in humans cognitive vitality with aging.

  11. Cooling and freezing of sperm from captive, free-living and endangered squirrel monkey species.

    Science.gov (United States)

    Oliveira, Karol G; Santos, Regiane R; Leão, Danuza L; Brito, Adriel B; Lima, Julianne S; Sampaio, Wlaísa V; Domingues, Sheyla F S

    2016-06-01

    Germoplasm banking is an important tool for the preservation of genetic material from Neotropical primates in captivity, and from free living species, especially the endangered ones like Saimiri vanzolinii (Black-headed squirrel monkey), a primate with a low incidence area (870 km(2) of floodplains) in the southern part of the Mamirauá Sustainable Development Reserve, Brazil. Therefore, in the present study we aimed to develop a sperm cryopreservation protocol comparing sperm cooling in presence (T1) and absence (T2) of egg yolk, and to test freezing protocols to preserve semen from captive (Saimiri collinsi), and free-living (Saimiri vanzolinii, Saimiri cassiquiarensis and Saimiri macrodon) New World primates. Cooling preserved sperm of S. collinsi in all evaluated microscopic parameters, except for sperm motility. No differences were observed among the treatments, indicating that semen of this species can be cooled without egg yolk. Freezing did not affect sperm quality of S. collinsi, except plasma membrane integrity that was negatively affected. Generally, a good maintenance rate was observed between cooling and thawing of semen for the four species, showing the positive translational application of protocols from S. collinsi to the free-living species. Developed freezing protocol proved to be useful for sperm cryopreservation of S. collinsi and in field conditions.

  12. The geographic selection mosaic for ponderosa pine and crossbills: a tale of two squirrels.

    Science.gov (United States)

    Parchman, Thomas L; Benkman, Craig W

    2008-02-01

    Recent research demonstrates how the occurrence of a preemptive competitor (Tamiasciurus) gives rise to a geographic mosaic of coevolution for crossbills (Loxia) and conifers. We extend these studies by examining ponderosa pine (Pinus ponderosa), which produces more variable annual seed crops than the conifers in previous studies and often cooccurs with tree squirrels in the genus Sciurus that are less specialized than Tamiasciurus on conifer seed. We found no evidence of seed defenses evolving in response to selection exerted by S. aberti, which was apparently overwhelmed by selection resulting from inner bark feeding that caused many developing cones to be destroyed. In the absence of S. aberti, defenses directed at crossbills increased, favoring larger-billed crossbills and causing stronger reciprocal selection between crossbills and ponderosa pine. However, crossbill nomadism in response to cone crop fluctuations prevents localized reciprocal adaptation by crossbills. In contrast, evolution in response to S. griseus has incidentally defended cones against crossbills, limiting the geographic range of the interaction between crossbills and ponderosa pine. Our results suggest that annual resource variation does not prevent competitors from shaping selection mosaics, although such fluctuations likely prevent fine-scale geographic differentiation in predators that are nomadic in response to resource variability.

  13. Food supplements modulate changes in leucocyte numbers in breeding male ground squirrels.

    Science.gov (United States)

    Bachman, Gwendolyn C

    2003-07-01

    Immunosuppression may be an important cost of reproduction in breeding males. It can result from elevated levels of testosterone or stress hormones and may serve to lower the energetic cost of maintaining immune function at a time of high demand. This suggests that greater access to energy resources could reduce immunosuppression as a cost of reproduction, minimizing the trade-off between energetic investment in current reproductive effort and survival. I examined the impact of food availability on immune function by provisioning male Belding's ground squirrels in the field from the time they emerged from hibernation to the start of breeding. Temporal changes in immune status, measured by leucocyte counts, differed between provisioned males and un-provisioned controls. Provisioning advanced the increase in lymphocytes and neutrophils from after breeding to before. At the start of breeding, the leucocyte count was three times greater in provisioned males than in controls and was still nearly twice as great at the end of breeding. Control males increased all leucocyte numbers after breeding. This experiment demonstrates that variation in food intake can lead to individual variation in the extent of immunosuppression during breeding and therefore that reduced immune function may not be an obligatory cost of reproduction.

  14. Increasing length of wakefulness and modulation of hypocretin-1 in the wake-consolidated squirrel monkey.

    Science.gov (United States)

    Zeitzer, Jamie M; Buckmaster, Christine L; Lyons, David M; Mignot, Emmanuel

    2007-10-01

    The neuropeptides hypocretins (orexins), the loss of which results in the sleep disorder narcolepsy, are hypothesized to be involved in the consolidation of wakefulness and have been proposed to be part of the circadian-driven alertness signal. To elucidate the role of hypocretins in the consolidation of human wakefulness we examined the effect of wake extension on hypocretin-1 in squirrel monkeys, primates that consolidate wakefulness during the daytime as do humans. Wake was extended up to 7 h with hypocretin-1, cortisol, ghrelin, leptin, locomotion, and feeding, all being assayed. Hypocretin-1 (P sleep deprivation, while ghrelin (P = 0.79) and leptin (P = 1.00) did not change with sleep deprivation. Using cross-correlation and multivariate modeling of these potential covariates along with homeostatic pressure (a measure of time awake/asleep), we found that time of day and homeostatic pressure together explained 44% of the variance in the hypocretin-1 data (P sleep pressure. Concomitants of wakefulness that affect hypocretin-1 in polyphasic species, such as locomotion, food intake, and food deprivation, likely have a more minor role in monophasic species, such as humans.

  15. Neuronal Control of Mammalian Vocalization, with Special Reference to the Squirrel Monkey

    Science.gov (United States)

    Jürgens, Uwe

    Squirrel monkey vocalization can be considered as a suitable model for the study in humans of the neurobiological basis of nonverbal emotional vocal utterances, such as laughing, crying, and groaning. Evaluation of electrical and chemical brain stimulation data, lesioning studies, single-neurone recordings, and neuroanatomical tracing work leads to the following conclusions: The periaqueductal gray and laterally bordering tegmentum of the midbrain represent a crucial area for the production of vocalization. This area collects the various vocalization-triggering stimuli, such as auditory, visual, and somatosensory input from diverse sensory-processing structures, motivation-controlling input from some limbic structures, and volitional impulses from the anterior cingulate cortex. Destruction of this area causes mutism. It is still under dispute whether the periaqueductal region harbors the vocal pattern generator or merely couples vocalization-triggering information to motor-coordinating structures further downward in the brainstem. The periaqueductal region is connected with the phonatory motoneuron pools indirectly via one or several interneurons. The nucleus retroambiguus represents a crucial relay station for the laryngeal and expiratory component of vocalization. The articulatory component reaches the orofacial motoneuron pools via the parvocellular reticular formation. Essential proprioceptive feedback from the larynx and lungs enter the vocal-controlling network via the solitary tract nucleus.

  16. Morphological Features of Trypanosomes from Squirrel Monkeys from the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Mariangela Ziccardi

    1998-01-01

    Full Text Available A morphometric analysis of blood trypomastigotes identified as Trypanosoma minasense, T. saimirii, and T. rangeli harbored by squirrel monkeys from the Brazilian Amazon was performed. Additionally, morphological and biological comparative analyses were conducted of T. saimirii-like and T. rangeli development forms from haemoculture and xenodiagnosis. Illustrations are given of blood trypomastigotes as well as of developing flagellates in triatomine and axenic culture. Mean values of blood trypomastigotes of T. saimirii differ statistically from those of T. rangeli in only two out of ten morphological characters measured, and ranges overlapped. The developing forms of T. saimrii-like parasites were essentially identical in both xenodiagnosis and haemoculture to those of T. rangeli. Trypanosomes confirmed as T. rangeli were transmitted to mice by the bites of the great majority of triatomines that fed on T. saimirii-like infected monkeys. We conclude that, based on morphology and on the development in triatomine bugs and haemoculture, T. saimirii should not be considered a distinct species. We therefore propose T. saimirii to be a junior synonym of T. rangeli

  17. Hippocampal neurogenesis in food-storing red squirrels: the impact of age and spatial behavior.

    Science.gov (United States)

    Johnson, K M; Boonstra, R; Wojtowicz, J M

    2010-08-01

    The adaptive significance of adult hippocampal neurogenesis remains unknown. In the laboratory, it is influenced by a variety of environmental and physiological stimuli. In the wild, it may be influenced by the reliance on spatial memory and by environmental stressors. The one common denominator in both settings is that neurogenesis declines markedly with age. Red squirrels are long-lived rodents that store food (thousands of tree cones) to permit survival under harsh winter conditions. We compared a population from the eastern North America that stores its cones singly or in small clusters with one from the west that stores its cones in large stockpiles. The reliance on spatial memory should be much greater in the east than the west, and should not decline with age, as cone storage and recovery is a yearly necessity. We found no difference between the populations in the density of young neurons and both populations showed the same decline with age. Thus, we reject the spatial memory hypothesis for adult neurogenesis in mammals in its original form. Instead, our evidence is consistent with the neurogenic reserve hypothesis in which neuronal cell production early in life leads to enhanced hippocampal function later in life according to environmental demand but without requirement for ongoing cell production as a function of site- and species-specific needs. A more general interpretation of the data leads us to consider a possible role of neurogenesis in novel, flexible episodic memories.

  18. Light masking of circadian rhythms of heat production, heat loss, and body temperature in squirrel monkeys

    Science.gov (United States)

    Robinson, E. L.; Fuller, C. A.

    1999-01-01

    Whole body heat production (HP) and heat loss (HL) were examined to determine their relative contributions to light masking of the circadian rhythm in body temperature (Tb). Squirrel monkey metabolism (n = 6) was monitored by both indirect and direct calorimetry, with telemetered measurement of body temperature and activity. Feeding was also measured. Responses to an entraining light-dark (LD) cycle (LD 12:12) and a masking LD cycle (LD 2:2) were compared. HP and HL contributed to both the daily rhythm and the masking changes in Tb. All variables showed phase-dependent masking responses. Masking transients at L or D transitions were generally greater during subjective day; however, L masking resulted in sustained elevation of Tb, HP, and HL during subjective night. Parallel, apparently compensatory, changes of HL and HP suggest action by both the circadian timing system and light masking on Tb set point. Furthermore, transient HL increases during subjective night suggest that gain change may supplement set point regulation of Tb.

  19. Growth and differentiation of adult hippocampal arctic ground squirrel neural stem cells.

    Science.gov (United States)

    Drew, Kelly L; McGee, Rebecca C; Wells, Matthew S; Kelleher-Andersson, Judith A

    2011-01-07

    Arctic ground squirrels (Urocitellus parryii, AGS) are unique in their ability to hibernate with a core body temperature near or below freezing. These animals also resist ischemic injury to the brain in vivo and oxygen-glucose deprivation in vitro. These unique qualities provided the impetus to isolate AGS neurons to examine inherent neuronal characteristics that could account for the capacity of AGS neurons to resist injury and cell death caused by ischemia and extremely cold temperatures. Identifying proteins or gene targets that allow for the distinctive properties of these cells could aid in the discovery of effective therapies for a number of ischemic indications and for the study of cold tolerance. Adult AGS hippocampus contains neural stem cells that continue to proliferate, allowing for easy expansion of these stem cells in culture. We describe here methods by which researchers can utilize these stem cells and differentiated neurons for any number of purposes. By closely following these steps the AGS neural stem cells can be expanded through two passages or more and then differentiated to a culture high in TUJ1-positive neurons (~50%) without utilizing toxic chemicals to minimize the number of dividing cells. Ischemia induces neurogenesis and neurogenesis which proceeds via MEK/ERK and PI3K/Akt survival signaling pathways contributes to ischemia resistance in vivo and in vitro (Kelleher-Anderson, Drew et al., in preparation). Further characterization of these unique neural cells can advance on many fronts, using some or all of these methods.

  20. Susceptibility of low-chill blueberry cultivars to oriental fruit fly, mediterranean fruit fly, and melon fly (Diptera: Tephritidae)

    Science.gov (United States)

    Forced infestation studies were conducted to determine if fruits of southern highbush blueberries (Vaccinium corymbosum L. hybrids) are hosts for three invasive tephritid fruit flies. Fruits of 17 blueberry cultivars were exposed to gravid female flies of Bactrocera dorsalis (Hendel) (oriental frui...

  1. Home-range use patterns and movements of the Siberian flying squirrel in urban forests: Effects of habitat composition and connectivity

    NARCIS (Netherlands)

    Mäkeläinen, Sanna; Knegt, de H.J.; Ovaskainen, Otso; Hanski, Ilpo K.

    2016-01-01

    Urbanization causes modification, fragmentation and loss of native habitats. Such landscape changes threaten many arboreal and gliding mammals by limiting their movements through treeless parts of a landscape and by making the landscape surrounding suitable habitat patches more inhospitable. Here, w

  2. Self hardening property of Botswana fly ash | Sahu | Botswana ...

    African Journals Online (AJOL)

    Self hardening property of Botswana fly ash. ... In the present investigation, an effort has been made to study the self hardening property of Botswana fly ash by ... This will encourage the use of fly ash economically as a construction material.

  3. Analysis of Three-Phase Squirrel-Cage Asynchronous Motor Vibration Fault%笼型三相异步电机振动故障解析

    Institute of Scientific and Technical Information of China (English)

    王强; 陈金刚

    2013-01-01

    介绍笼型三相异步电机的振动测量和振动超标造成的危害.从机械和电磁两方面阐述笼型三相异步电机的振动故障表现和修理预防措施.%The vibration measurement and vibration exceeding the standard hazards of squirrel-cage three-phase asynchronous motor were introduced.The vibration fault performances and repair prevention measures of three-phase squirrel-cage motor were elaborated from the mechanical and electromagnetic aspects.

  4. An invasive mammal (the gray squirrel, Sciurus carolinensis) commonly hosts diverse and atypical genotypes of the zoonotic pathogen Borrelia burgdorferi sensu lato

    DEFF Research Database (Denmark)

    Millins, Caroline; Magierecka, Agnieszka; Gilbert, Lucy;

    2015-01-01

    Invasive vertebrate species can act as hosts for endemic pathogens and may alter pathogen community composition and dynamics. For the zoonotic pathogen Borrelia burgdorferi sensu lato, the agent of Lyme borreliosis, recent work shows invasive rodent species can be of high epidemiological importance...... in squirrels infested with ticks. Invasive grey squirrels appear to become infected with locally circulating strains of B. burgdorferi s.l., further studies are required to determine their role in community disease dynamics. Our findings highlight that the role of introduced host species in B. burgdorferi s...

  5. A fly larva (Syrphidae: Ocyptamus that preys on adult flies

    Directory of Open Access Journals (Sweden)

    Onanchi Ureña

    2010-12-01

    Full Text Available Predatory syrphid larvae feed on relatively immobile prey, but here we report the first case (as far as we are aware of obligatory predation on very mobile prey. Larvae of an undescribed species of Ocyptamus (Diptera: Syrphidae were found in whitefly (Hemiptera: Aleyrodidae aggregations on the undersides of citrus leaves. However, instead of preying on the whitefly nymphs (as would be expected, the larvae preyed on adult flies (Diptera that were attracted to the honeydew. In the laboratory, larvae captured significantly more flies on whitefly infested leaves than on washed leaves, and generally abandoned leaves that lacked whiteflies. Most cases of successful prey capture involved flies that probed the anterior part of the larva’s body with its proboscis (as if it were honeydew. The syrphid larva lashed out at the fly and entangled it in sticky oral secretion. The prey did not recover when they were removed from the larva, suggesting that this new predatory species also employs venom to subdue its prey. Although the larvae consumed some honeydew, they were unable to complete their development on this diet. Two parasitoids were reared from Ocyptamus puparia, Proaspicera sp. (Hymenoptera: Figitidae and Paracarotomus sp. (Hymenoptera: Pteromalidae, both of which are endoparasitic koinobionts. Rev. Biol. Trop. 58 (4: 1157-1163. Epub 2010 December 01.Las larvas depredadoras de Syrphidae se alimentan de presas relativamente inmóviles, pero aquí reportamos el primer caso (hasta ahora conocido de la depredación obligatoria en presas muy móviles. Se encontraron las larvas de una especie no descrita de Ocyptamus (Diptera: Syrphidae juntas con ninfas de mosca blanca (Hemiptera: Aleyrodidae en el envés de las hojas de cítricos. Sin embargo, en vez de alimentarse de las ninfas de mosca blanca (como debería esperarse, las larvas se alimentaron de moscas adultas (Diptera que fueron atraídas a las excreciones azucaradas de la mosca blanca. En el

  6. Requirements for satisfactory flying qualities of airplanes

    Science.gov (United States)

    Gilruth, R R

    1943-01-01

    Report discusses the results of an analysis of available data to determine what measured characteristics are significant in defining satisfactory flying qualities, what characteristics are reasonable to require of an airplane, and what influence the various design features have on the observed flying qualities.

  7. MODAL CONTROL OF PILOTLESS FLYING MACHINE

    Directory of Open Access Journals (Sweden)

    V. A. Antanevich

    2010-01-01

    Full Text Available The paper considers a problem on synthesis of lateral movement control algorithms in a pilotless flying machine which is made on the basis of a modal control method providing a required root arrangement of a characteristic closed control system polynom. Results of the modeling at stabilization of a lateral pilotless flying machine co-ordinate are presented in the paper.

  8. Flying Probe Tester: Architecture, Principle and Implementation

    Institute of Scientific and Technical Information of China (English)

    Fu,Xu; Fang,Kangling; Chen,Guoqing

    2005-01-01

    This paper introduces the flying probe tester, which is a testing device for PCB. The architecture and principle of flying probe tester are firstly introduced. Then the implementation of hardware and software is illuminated briefly. Finally, the optimizing method for the probe's moving path is researched based on the traveling salesman problem.

  9. Low back pain and low level flying

    NARCIS (Netherlands)

    J.C.F.M. Aghina

    1989-01-01

    textabstractLow level flying is a very good tactical possibility to carry out a mission unseen by a hostile radarsystem. Nowadays, Western Europe in general and the Federal Republic of Germany in particular, decreased . the permissions to low level flying in assigned regions. That's why the

  10. Testing for Mutagens Using Fruit Flies.

    Science.gov (United States)

    Liebl, Eric C.

    1998-01-01

    Describes a laboratory employed in undergraduate teaching that uses fruit flies to test student-selected compounds for their ability to cause mutations. Requires no prior experience with fruit flies, incorporates a student design component, and employs both rigorous controls and statistical analyses. (DDR)

  11. Catch Composition of Tsetse Flies (Glossina: Glossinidae

    Directory of Open Access Journals (Sweden)

    K. E. Okoh

    2011-01-01

    Full Text Available Problem statement: A study to determine the composition of tsetse flies species was conducted between January and December, 2007 in Kamuku National Park, Nigeria, using Biconical and Nitse traps. Tsetse flies were trapped along gallery forest in five streams for two trapping days and were collected daily. Approach: All tsetse flies caught were identified to species level, sexed, separated into teneral and non-teneral, hunger staged and Mean Hunger Stage computed. Fly density were calculated, the age structure examined using wing fray techniques for males and ovarian technique for females; the reproductive status of female flies were assessed. Two species of tsetse flies (Glossina palpalis palpalis robineau-desvoidy and Glossina tachinoides Westwood were caught in total of five hundred and two (502 flies. Out of these, 309(61.6% Glossina tachinoides and 193(38.4% G. palpalis were caught. Male catches (309, 61.6% were significantly (P Results: The estimated mean age for males was 11 days and females were 8 days. The insemination rate of 93.8% generally was high, G. tachinoides recorded 95.5% more than G. palpalis of 91.6%. Whereas parity rate (25.8% was low; G. palpalis was 37.4% while G. tachinoides parity rate is 17.2%. Conclusion: The study shows that two species of tsetse flies abound in the park although at low densities their presence may bear semblance to Trypanosomiasis and its impact to ecotourism.

  12. Physicochemical characterization of Spanish fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Querol, X.; Umana, J.C.; Alastuey, A.; Bertrana, C.; Lopez-Soler, A.; Plana, F.

    1999-12-01

    This article summarizes the results obtained from the physical, chemical, and mineralogical characterization of 14 fly ash samples. Major features that influence the utilization of each fly ash for zeolite synthesis are evidenced, and several fly ash types were selected as potential high-quality starting material for zeolite synthesis and ceramic applications. The main parameters influencing this selection were relatively small grain size; high Al and Si contents; high glass content; low CaO, S, and Fe contents; and relatively low heavy metal concentration. The Compostilla and Cou He fly ashes have high potential applications because of the low content of major impurities (such as Ca, Fe, and S) and the low content of soluble hazardous elements. The Espiel, Escucha, Los Barrios, As Pontes, Soto de Ribera, Meirama, Narcea, and Teruel fly ashes have important application potential, but this potential is slightly limited by the intermediate content of nonreactive impurities, such as Fe and Ca. The La Robla fly ash is of moderate interest, since the relatively high Ca and Fe oxide contents may reduce its potential applications. Finally, the Puertollano fly ash also has limited application because of the very high concentration of some heavy metals such as As, Cd, Ge, Hg, Pb, and Zn. From a mineralogical point of view, the Compostilla, Espiel, and Soto de Ribera fly ashes show the highest aluminum-silicate glass content and, consequently, the highest industrial application potential.

  13. Physiochemical characterization of Spanish fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Querol, X.; Umana, J.C.; Alastuey, A.; Bertrana, C.; Lopez Soler, A.; Plana, F.

    1999-12-01

    This article summarizes the results obtained from the physical, chemical, and mineralogical characterization of 14 fly ash samples. Major features that influence the utilization of each fly ash for zeolite synthesis are evidenced, and several fly ash types were selected as potential high-quality starting material for zeolite synthesis and ceramic applications. The main parameters influencing this selection were relatively small grain size; high Al and Si contents; high glass content; low CaO, S, and Fe contents; and relatively low heavy metal concentration. The Compostilla and Dou He fly ashes have high potential applications because of the low content of major impurities (such as Ca, Fe, and S) and the low content of soluble hazardous elements. The Espiel, Escucha, Los Barrios, As Pontes, Soto de Ribera, Meirama, Narcea, and Teruel fly ashes have important application potential, but this potential is slightly limited by the intermediate content of nonreactive impurities, such as Fe and Ca. The La Robla fly ash is of moderate interest, since the relatively high Ca and Fe oxide contents may reduce its potential applications. Finally, the Puertollano fly ash also has limited application because of the very high concentration of some heavy metals such as As, Cd, Ge, Hg, Pb, and Zn. From a mineralogical point of view, the Compostilla, Espiel, and Soto de Ribera fly ashes show the highest aluminum-silicate glass content and, consequently, the highest industrial application potential. (author)

  14. Low back pain and low level flying

    NARCIS (Netherlands)

    J.C.F.M. Aghina

    1989-01-01

    textabstractLow level flying is a very good tactical possibility to carry out a mission unseen by a hostile radarsystem. Nowadays, Western Europe in general and the Federal Republic of Germany in particular, decreased . the permissions to low level flying in assigned regions. That's why the Royal Ne

  15. Construction procedures using self hardening fly ash

    Science.gov (United States)

    Thornton, S. I.; Parker, D. G.

    1980-07-01

    Fly ash produced in Arkansas from burning Wyoming low sulfur coal is self-hardening and can be effective as a soil stabilizing agent for clays and sands. The strength of soil-self hardening fly ash develops rapidly when compacted immediately after mixing. Seven day unconfined compressive strengths up to 1800 psi were obtained from 20% fly ash and 80% sand mixtures. A time delay between mixing the fly ash with the soil and compaction of the mixture reduced the strength. With two hours delay, over a third of the strength was lost and with four hours delay, the loss was over half. Gypsum and some commercial concrete retarders were effective in reducing the detrimental effect of delayed compaction. Adequate mixing of the soil and fly ash and rapid compaction of the mixtures were found to be important parameters in field construction of stabilized bases.

  16. Nectin-4 Interactions Govern Measles Virus Virulence in a New Model of Pathogenesis, the Squirrel Monkey (Saimiri sciureus).

    Science.gov (United States)

    Delpeut, Sébastien; Sawatsky, Bevan; Wong, Xiao-Xiang; Frenzke, Marie; Cattaneo, Roberto; von Messling, Veronika

    2017-06-01

    In addition to humans, only certain nonhuman primates are naturally susceptible to measles virus (MeV) infection. Disease severity is species dependent, ranging from mild to moderate for macaques to severe and even lethal for certain New World monkey species. To investigate if squirrel monkeys (Saimiri sciureus), which are reported to develop a course of disease similar to humans, may be better suited than macaques for the identification of virulence determinants or the evaluation of therapeutics, we infected them with a green fluorescent protein-expressing MeV. Compared to cynomolgus macaques (Macaca fascicularis) infected with the same virus, the squirrel monkeys developed more-severe immunosuppression, higher viral load, and a broader range of clinical signs typical for measles. In contrast, infection with an MeV unable to interact with the epithelial receptor nectin-4, while causing immunosuppression, resulted in only a mild and transient rash and a short-lived elevation of the body temperature. Similar titers of the wild-type and nectin-4-blind MeV were detected in peripheral blood mononuclear cells and lymph node homogenates, but only the wild-type virus was found in tracheal lavage fluids and urine. Thus, our study demonstrates the importance of MeV interactions with nectin-4 for clinical disease in the new and better-performing S. sciureus model of measles pathogenesis.IMPORTANCE The characterization of mechanisms underlying measles virus clinical disease has been hampered by the lack of an animal model that reproduces the course of disease seen in human patients. Here, we report that infection of squirrel monkeys (Saimiri sciureus) fulfills these requirements. Comparative infection with wild-type and epithelial cell receptor-blind viruses demonstrated the importance of epithelial cell infection for clinical disease, highlighting the spread to epithelia as an attractive target for therapeutic strategies. Copyright © 2017 American Society for Microbiology.

  17. Do black-furred animals compensate for high solar absorption with smaller hairs? A test with a polymorphic squirrel species

    Directory of Open Access Journals (Sweden)

    Melanie A. FRATTO, Andrew K. DAVIS

    2011-12-01

    Full Text Available In polymorphic mammalian species that display multiple color forms, those with dark, or melanic pelage would be prone to overheating, especially if they live in warm climates, because their fur absorbs solar energy at a higher rate. However, experimental studies indicate that certain physical properties of fur of dark individuals appear to prevent, or minimize heat stress, although it is not clear what properties do so. Here, we tested the possibility that black-furred individuals simply have shorter or thinner hair fibers, which would create a lighter (in terms of weight coat or one that allows greater air flow for evaporative coo- ling. We examined museum specimens of eastern fox squirrels Sciurus niger, a species native to the United States and one that displays brown, grey or all-black pelage color, and used image analysis procedures to quantify hairs from the dorsal surface and tail. From examination of 43 specimens (19 brown, 9 black and 15 grey, and 1,720 hairs, we found no significant difference in hair lengths across color morphs, but significant differences in hair fiber widths. Black squirrels had thinner body hairs than other forms (7% thinner, but thicker tail hairs (9% thicker than the others. Given that the dorsal surface would be directly exposed to solar radiation, we interpret this to be an adaptation to prevent heat stress during the day. The thicker tail hairs may be an adaptation for nighttime thermoregulation, since squirrels sleep with their tails wrapped around their bodies. These results add to a growing literature body of the functional significance of mammalian pelage [Current Zoology 57 (6: 731–736, 2011].

  18. Cytoskeletal regulation dominates temperature-sensitive proteomic changes of hibernation in forebrain of 13-lined ground squirrels.

    Directory of Open Access Journals (Sweden)

    Allyson G Hindle

    Full Text Available 13-lined ground squirrels, Ictidomys tridecemlineatus, are obligate hibernators that transition annually between summer homeothermy and winter heterothermy - wherein they exploit episodic torpor bouts. Despite cerebral ischemia during torpor and rapid reperfusion during arousal, hibernator brains resist damage and the animals emerge neurologically intact each spring. We hypothesized that protein changes in the brain underlie winter neuroprotection. To identify candidate proteins, we applied a sensitive 2D gel electrophoresis method to quantify protein differences among forebrain extracts prepared from ground squirrels in two summer, four winter and fall transition states. Proteins that differed among groups were identified using LC-MS/MS. Only 84 protein spots varied significantly among the defined states of hibernation. Protein changes in the forebrain proteome fell largely into two reciprocal patterns with a strong body temperature dependence. The importance of body temperature was tested in animals from the fall; these fall animals use torpor sporadically with body temperatures mirroring ambient temperatures between 4 and 21°C as they navigate the transition between summer homeothermy and winter heterothermy. Unlike cold-torpid fall ground squirrels, warm-torpid individuals strongly resembled the homeotherms, indicating that the changes observed in torpid hibernators are defined by body temperature, not torpor per se. Metabolic enzymes were largely unchanged despite varied metabolic activity across annual and torpor-arousal cycles. Instead, the majority of the observed changes were cytoskeletal proteins and their regulators. While cytoskeletal structural proteins tended to differ seasonally, i.e., between summer homeothermy and winter heterothermy, their regulatory proteins were more strongly affected by body temperature. Changes in the abundance of various isoforms of the microtubule assembly and disassembly regulatory proteins

  19. Do black-furred animals compensate for high solar absorption with smaller hairs? A test with a polymorphic squirrel species

    Institute of Scientific and Technical Information of China (English)

    Melanie A. FRATTO; Andrew K. DAVIS

    2011-01-01

    In polymorphic mammalian species that display multiple color forms,those with dark,or melanic pelage would be prone to overheating,especially if they live in warm climates,because their fur absorbs solar energy at a higher rate.However,experimental studies indicate that certain physical properties of fur of dark individuals appear to prevent,or minimize heat stress,although it is not clear what properties do so.Here,we tested the possibility that black-furred individuals simply have shorter or thinner hair fibers,which would create a lighter (in terms of weight) coat or one that allows greater air flow for evaporative cooling.We examined museum specimens of eastern fox squirrels Sciurus niger,a species native to the United States and one that displays brown,grey or all-black pelage color,and used image analysis procedures to quantify hairs from the dorsal surface and tail.From examination of 43 specimens (19 brown,9 black and 15 grey),and 1,720 hairs,we found no significant difference in hair lengths across color morphs,but significant differences in hair fiber widths.Black squirrels had thinner body hairs than other forms (7% thinner),but thicker tail hairs (9% thicker) than the others.Given that the dorsal surface would be directly exposed to solar radiation,we interpret this to be an adaptation to prevent heat stress during the day.The thicker tail hairs may be an adaptation for nighttime thermoregulation,since squirrels sleep with their tails wrapped around their bodies.These results add to a growing literature body of the functional significance of mammalian pelage [Current Zoology 57 (6):731-736,2011].

  20. Distribution of neprilysin and deposit patterns of Abeta subtypes in the brains of aged squirrel monkeys (Saimiri sciureus).

    Science.gov (United States)

    Chambers, James K; Kuribayashi, Hiroyuki; Ikeda, Shu-Ichi; Une, Yumi

    2010-06-01

    Beta-amyloid (Abeta) is deposited in the parenchyma and blood vessel walls of the senescent brain, and forms lesions termed senile plaques (SPs) and cerebral amyloid angiopathy (CAA). Since in Alzheimer's disease (AD) excessive Abeta is linked to cognitive deterioration, the mechanisms of degradation and clearance of Abeta are now being researched for use in AD therapy. We conducted an immunohistochemical study of the patterns of deposition of two Abeta subtypes (Abeta40 and Abeta42) and the distribution of the Abeta degrading enzyme neprilysin (NEP) in the brains of aged squirrel monkeys, a species known to develop CAA and SPs. Abeta deposits were observed mainly in the cerebral cortex of five older monkeys, and were absent in monkeys under 12 years of age. NEP expression was observed in the caudate nucleus, putamen, globus pallidus, substantia nigra and the molecular layer of the dentate gyrus, and thus exhibited a distribution complementary to those of CAA and SPs in cerebral cortex and hippocampus. It is known that CAA is more prominent than SPs in squirrel monkey brains. However, we confirmed that Abeta40 is deposited predominantly in the arterioles of the meninges and penetrates vertically into the cerebral cortex, whereas Abeta42 is deposited predominantly in the capillaries of the cerebral cortex. These distinct patterns of deposition of Abeta subtypes are likely related to the difference in biochemical character of these two subtypes. We have demonstrated for the first time the distribution of NEP in the brain of a non-human primate, the squirrel monkey, which appears useful for research on AD treatment.

  1. TrackFly: virtual reality for a behavioral system analysis in free-flying fruit flies.

    Science.gov (United States)

    Fry, Steven N; Rohrseitz, Nicola; Straw, Andrew D; Dickinson, Michael H

    2008-06-15

    Modern neuroscience and the interest in biomimetic control design demand increasingly sophisticated experimental techniques that can be applied in freely moving animals under realistic behavioral conditions. To explore sensorimotor flight control mechanisms in free-flying fruit flies (Drosophila melanogaster), we equipped a wind tunnel with a Virtual Reality (VR) display system based on standard digital hardware and a 3D path tracking system. We demonstrate the experimental power of this approach by example of a 'one-parameter open loop' testing paradigm. It provided (1) a straightforward measure of transient responses in presence of open loop visual stimulation; (2) high data throughput and standardized measurement conditions from process automation; and (3) simplified data analysis due to well-defined testing conditions. Being based on standard hardware and software techniques, our methods provide an affordable, easy to replicate and general solution for a broad range of behavioral applications in freely moving animals. Particular relevance for advanced behavioral research tools originates from the need to perform detailed behavioral analyses in genetically modified organisms and animal models for disease research.

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

    National Research Council Canada - National Science Library

    Song Chang; Z. Jane Wang

    2014-01-01

    .... 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...

  3. Biomass fly ash in concrete: SEM, EDX and ESEM analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shuangzhen Wang; Larry Baxter; Fernando Fonseca [Brigham Young University, Provo, UT (USA). Department of Chemical Engineering

    2008-03-15

    This document summarizes microscopy study of concrete prepared from cement and fly ash (25% fly ash and 75% cement by weight), which covers coal fly ash and biomass fly ash. All the fly ash concrete has the statistical equal strength from one day to one year after mix. Scanning electron microscopy (SEM), Energy dispersive X-ray (EDX) and environmental scanning electron microscopy (ESEM) analysis show that both coal and biomass fly ash particles undergo significant changes of morphology and chemical compositions in concrete due to pozzolanic reaction, although biomass fly ash differs substantially from coal fly ash in its fuel resources. 8 refs., 17 figs., 1 tab.

  4. Electrodialytic removal of heavy metals from fly ashes

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul

    2002-01-01

    The aim of the Ph.D. work was to develop the electrodialytic remediation method for removal of heavy metals from fly ashes. The work was focused on two types of fly ashes: fly ashes from wood combustion and fly ashes from municipal solid waste incineration.......The aim of the Ph.D. work was to develop the electrodialytic remediation method for removal of heavy metals from fly ashes. The work was focused on two types of fly ashes: fly ashes from wood combustion and fly ashes from municipal solid waste incineration....

  5. Sexual dimorphism in the squirrel monkey, Saimiri sciureus (Linnaeus, 1758) and Saimiri ustus (I. Geoffroy, 1844) (Primates, Cebidae).

    Science.gov (United States)

    Goldschmidt, B; Mota-Marinho, A; Araújo-Lopes, C; Brück-Gonçalves, M A; Matos-Fasano, D; Ribeiro-Andrade, M C; Ferreira-Nascimento, L W; Simmer-Bravin, J; Monnerat-Nogueira, D

    2009-02-01

    Causes and implications of sexual dimorphism have been studied in several different primates using a variety of morphological characters such as body weight, canine length, coat color and ornamentation. Here we describe a peculiar coat color characteristic in the squirrel monkey that is present only in adult females over five years old and which increases with age. Neither males nor young animals manifest this phenomenon, which is characterized by a spot of black hairs located anteriorly to the external ear (pinna). This characteristic could be used to discriminate adult females of Saimiri sciureus in the wild without the need of capture techniques.

  6. Avrocar: a real flying saucer

    CERN Document Server

    Fedrigo, Desire Francine G; Gobato, Alekssander

    2015-01-01

    One of the most unusual military aircraft programs V / STOL was the Avro VZ-9 "Avrocar". Designed to be a real flying saucer, the Avrocar was one of the few V / STOL to be developed in complete secrecy. Despite significant changes in the design, during flight tests, the Avrocar was unable to achieve its objectives, and the program was eventually canceled after an expenditure of 10 million US dollars between 1954 and 1961. But the concept of a lift fan, driven by a turbojet engine is not dead, and lives today as a key component of Lockheed X-35 Joint Strike Fighter contender. Was held in a data research and information related to Avrocar project carried out during the Second World War, which was directly linked to advances in aircraft that were built after it, and correlate them with the turbo fan engines used today.

  7. Trapping tsetse flies on water

    Directory of Open Access Journals (Sweden)

    Laveissière C.

    2011-05-01

    Full Text Available Riverine tsetse flies such as Glossina palpalis gambiensis and G. tachinoides are the vectors of human and animal trypanosomoses in West Africa. Despite intimate links between tsetse and water, to our knowledge there has never been any attempt to design trapping devices that would catch tsetse on water. In mangrove (Guinea one challenging issue is the tide, because height above the ground for a trap is a key factor affecting tsetse catches. The trap was mounted on the remains of an old wooden dugout, and attached with rope to nearby branches, thereby allowing it to rise and fall with the tide. Catches showed a very high density of 93.9 flies/”water-trap”/day, which was significantly higher (p < 0.05 than all the catches from other habitats where the classical trap had been used. In savannah, on the Comoe river of South Burkina Faso, the biconical trap was mounted on a small wooden raft anchored to a stone, and catches were compared with the classical biconical trap put on the shores. G. p. gambiensis and G. tachinoides densities were not significantly different from those from the classical biconical one. The adaptations described here have allowed to efficiently catch tsetse on the water, which to our knowledge is reported here for the first time. This represents a great progress and opens new opportunities to undertake studies on the vectors of trypanosomoses in mangrove areas of Guinea, which are currently the areas showing the highest prevalences of sleeping sickness in West Africa. It also has huge potential for tsetse control using insecticide impregnated traps in savannah areas where traps become less efficient in rainy season. The Guinean National control programme has already expressed its willingness to use such modified traps in its control campaigns in Guinea, as has the national PATTEC programme in Burkina Faso during rainy season.

  8. Testicular and serum testosterone variations in squirrel monkeys during seasonal cyclicity.

    Science.gov (United States)

    Pasqualini, T; Colillas, O; Rivarola, M A

    1986-01-01

    The seasonal testicular maturation of squirrel monkeys (Saimiri sciureus) was used as a model of maturational hormonal regulation of the testis. Testicular testosterone and serum testosterone concentrations were determined during the circannual variations of body weight and testicular volume. These data have been correlated with changes in the germinal epithelium. According to individual weight curves and time of the year, the monkeys were divided into five groups: group A1, maximal weight, April-May; A2, July; A3, November; A4, minimal weight, February-March; and A5, March-April. Variations in testicular volume followed very closely variations in body weight. Sexual activity started at A1 and persisted in A2. A marked drop in the mean width of the germinal epithelium and the diameters of the seminiferous tubules was observed in A3, followed by a recovery during A4 and A5. Testicular testosterone showed two annual elevations. The first peak, 3.91 +/- 0.31 micrograms/g (mean +/- SE), coincided with the serum testosterone peak when body weight and testicular volume were high and the trophic response of the germinal epithelium was complete. The second peak reached levels of 5.21 +/- 1.48 micrograms/g and was observed before the reinitiation of spermatogenesis. This was accompanied by a moderate increase in serum testosterone. The second peak of testicular testosterone, which has been reported to occur in the rat and in humans, might represent a local androgen need for initiation of spermatogenesis, while the first peak might represent the androgen need for full stimulation of spermatogenesis.

  9. Distribution and ultrastructural features of the serotonin innervation in rat and squirrel monkey subthalamic nucleus.

    Science.gov (United States)

    Parent, Martin; Wallman, Marie-Josée; Descarries, Laurent

    2010-04-01

    The main purpose of this light and electron microscopic immunocytochemical study was to characterize and compare the serotonin (5-HT) innervation of the subthalamic nucleus (STN) in rats and squirrel monkeys (Saimiri sciureus) following labeling with an antibody against the 5-HT transporter (SERT). Unbiased counts of SERT+ axon varicosities revealed an average density of 5-HT innervation higher in monkeys (1.52 x 10(6) varicosities/mm3) than rats (1.17 x 10(6)), particularly in the anterior half of the nucleus (1.70 x 10(6)). As measured by electron microscopy, SERT+ axon varicosity profiles in the STN of both species were smaller than unlabeled profiles. The number of SERT+ profiles displaying a synaptic junction indicated that, in both rat and monkey STN, approximately half of 5-HT axon varicosities were asynaptic. In monkeys, all synaptic junctions made by SERT+ varicosities were asymmetrical, as opposed to only 77% in rats. Despite the higher density of 5-HT innervation in the anterior half of monkey STN, the ultrastructural features of its SERT+ varicosities, including synaptic incidence, did not significantly differ from those in its posterior half. These findings suggest that, throughout the rat and monkey STN, 5-HT afferents may exert their influence via both synaptic delivery and diffusion of 5-HT, and that an ambient level of 5-HT maintained in STN by these two modes of transmission might also modulate neuronal activity and influence motor behavior. A better understanding of the factors governing the complex interplay between these signaling processes would greatly improve our knowledge of the physiopathology of the STN.

  10. Effects of modified chromophores on the spectral sensitivity of salamander, squirrel and macaque cones.

    Science.gov (United States)

    Makino, C L; Kraft, T W; Mathies, R A; Lugtenburg, J; Miley, M E; van der Steen, R; Baylor, D A

    1990-05-01

    1. Chemically modified retinal chromophores were used to investigate the mechanisms that produce the characteristic spectral absorptions of cone pigments. Spectral sensitivities of single cones from the salamander, squirrel and macaque retina were determined by electrical recording. The chromophore was then replaced by bleaching the pigment and regenerating it with a retinal analogue. 2. Exposing a bleached cone to 9-cis-retinal for a brief period (less than 20 min) caused its flash sensitivity to recover to about 0.2 of the pre-bleach value. Similar exposure to a locked 6-s-cis, 9-cis analogue gave a recovery to about 0.03 of the pre-bleach value. 3. Unlike the flash sensitivity, the saturating photocurrent amplitude often recovered completely after bleaching and regenerating the pigment. 4. When the 3-dehydroretinal chromophore in the salamander long-wavelength-sensitive (red) cone was replaced with 11-cis-retinal, shortening the conjugated chain in the chromophore, the spectral sensitivity underwent a blue shift of 67 nm. 5. Pigments containing the planar-locked 6-s-cis.9-cis-retinal analogue absorbed at substantially longer wavelength than those containing unmodified 9-cis-retinal. The opsin shift, a measure of the protein's ability to modify the chromophore's absorption was larger for the locked analogue than for 9-cis-retinal. This suggests that the native chromophore assumes a twisted 6-s-cis conformation in these pigments. 6. The spectral sensitivities of red and green macaque cones containing 9-cis-retinal or planar-locked 6-s-cis.9-cis-retinal retained the 30 nm separation characteristic of the native pigments. This suggests that the different absorptions of of the 6-7 carbon bond in the retinal chromophore.

  11. Differential adaptation of the linear and nonlinear components of the horizontal vestibuloocular reflex in squirrel monkeys

    Science.gov (United States)

    Clendaniel, Richard A.; Lasker, David M.; Minor, Lloyd B.; Shelhamer, M. J. (Principal Investigator)

    2002-01-01

    Previous work in squirrel monkeys has demonstrated the presence of linear and nonlinear components to the horizontal vestibuloocular reflex (VOR) evoked by high-acceleration rotations. The nonlinear component is seen as a rise in gain with increasing velocity of rotation at frequencies more than 2 Hz (a velocity-dependent gain enhancement). We have shown that there are greater changes in the nonlinear than linear component of the response after spectacle-induced adaptation. The present study was conducted to determine if the two components of the response share a common adaptive process. The gain of the VOR, in the dark, to sinusoidal stimuli at 4 Hz (peak velocities: 20-150 degrees /s) and 10 Hz (peak velocities: 20 and 100 degrees /s) was measured pre- and postadaptation. Adaptation was induced over 4 h with x0.45 minimizing spectacles. Sum-of-sines stimuli were used to induce adaptation, and the parameters of the stimuli were adjusted to invoke only the linear or both linear and nonlinear components of the response. Preadaptation, there was a velocity-dependent gain enhancement at 4 and 10 Hz. In postadaptation with the paradigms that only recruited the linear component, there was a decrease in gain and a persistent velocity-dependent gain enhancement (indicating adaptation of only the linear component). After adaptation with the paradigm designed to recruit both the linear and nonlinear components, there was a decrease in gain and no velocity-dependent gain enhancement (indicating adaptation of both components). There were comparable changes in the response to steps of acceleration. We interpret these results to indicate that separate processes drive the adaptation of the linear and nonlinear components of the response.

  12. Conflict behavior in the squirrel monkey: effects of chlordiazepoxide, diazepam and N-desmethyldiazepam.

    Science.gov (United States)

    Sepinwall, J; Grodsky, F S; Cook, L

    1978-01-01

    Dose-response profiles were determined for chlordiazepoxide, diazepam and N-desmethyldiazepam in a squirrel monkey punishment (conflict) procedure. The monkeys were trained to lever press under a food-maintained concurrent schedule consisting of an unpunished 6-minute variable interval (VI) schedule, and a 1.5-minute VI schedule, on which responses were punished intermittently (24 response variable ratio) with electric footshocks. The three benzodiazepines effectively increased responding that had been suppressed by punishment; they had inverted U-shaped dose-effect curves. The minimum effective doses for increasing punished responding were: diazepam less than or equal to 0.31 mg/kg p.o.; N-desmethyldiazepam = chlordiazepoxide = 0.62 mg/kg. As a model to assess potential antianxiety activity, this procedure possessed excellent sensitivity and reliability. The following observations were also made. 1) During initial training, as shock intensity was increased and punished responding became suppressed, some monkeys exhibited an increase in unpunished response rates. This may have represented "positive behavioral contrast," but response rate changes were associated with changes in the amount of time the monkeys allocated to each schedule. 2) At certain dose levels, all three compounds exerted antipunishment effects 24 hours after administration. 3) As was reported previously for rats, when the monkeys had no previous drug experience ("drug-naive") they were more sensitive to the depressant effects of the benzodiazepines. With repeated administration, there was a reduction in this sedation and a concomitant increase in the antipunishment effect. This phenomenon was dose- and animal-dependent.

  13. Modeling the vestibulo-ocular reflex of the squirrel monkey during eccentric rotation and roll tilt

    Science.gov (United States)

    Merfeld, D. M.; Paloski, W. H. (Principal Investigator)

    1995-01-01

    Model simulations of the squirrel monkey vestibulo-ocular reflex (VOR) are presented for two motion paradigms: constant velocity eccentric rotation and roll tilt about a naso-occipital axis. The model represents the implementation of three hypotheses: the "internal model" hypothesis, the "gravito-inertial force (GIF) resolution" hypothesis, and the "compensatory VOR" hypothesis. The internal model hypothesis is based on the idea that the nervous system knows the dynamics of the sensory systems and implements this knowledge as an internal dynamic model. The GIF resolution hypothesis is based on the idea that the nervous system knows that gravity minus linear acceleration equals GIF and implements this knowledge by resolving the otolith measurement of GIF into central estimates of gravity and linear acceleration, such that the central estimate of gravity minus the central estimate of acceleration equals the otolith measurement of GIF. The compensatory VOR hypothesis is based on the idea that the VOR compensates for the central estimates of angular velocity and linear velocity, which sum in a near-linear manner. During constant velocity eccentric rotation, the model correctly predicts that: (1) the peak horizontal response is greater while "facing-motion" than with "back-to-motion"; (2) the axis of eye rotation shifts toward alignment with GIF; and (3) a continuous vertical response, slow phase downward, exists prior to deceleration. The model also correctly predicts that a torsional response during the roll rotation is the only velocity response observed during roll rotations about a naso-occipital axis. The success of this model in predicting the observed experimental responses suggests that the model captures the essence of the complex sensory interactions engendered by eccentric rotation and roll tilt.

  14. Energetic costs of parasitism in the Cape ground squirrel Xerus inauris

    Science.gov (United States)

    Scantlebury, M; Waterman, J.M; Hillegass, M; Speakman, J.R; Bennett, N.C

    2007-01-01

    Parasites have been suggested to influence many aspects of host behaviour. Some of these effects may be mediated via their impact on host energy budgets. This impact may include effects on both energy intake and absorption as well as components of expenditure, including resting metabolic rate (RMR) and activity (e.g. grooming). Despite their potential importance, the energy costs of parasitism have seldom been directly quantified in a field setting. Here we pharmacologically treated female Cape ground squirrels (Xerus inauris) with anti-parasite drugs and measured the change in body composition, the daily energy expenditure (DEE) using doubly labelled water, the RMR by respirometry and the proportions of time spent looking for food, feeding, moving and grooming. Post-treatment animals gained an average 19 g of fat or approximately 25 kJ d−1. DEE averaged 382 kJ d−1 prior to and 375 kJ d−1 post treatment (p>0.05). RMR averaged 174 kJ d−1 prior to and 217 kJ d−1 post treatment (p<0.009). Post-treatment animals spent less time looking for food and grooming, but more time on feeding. A primary impact of infection by parasites could be suppression of feeding behaviour and, hence, total available energy resources. The significant elevation of RMR after treatment was unexpected. One explanation might be that parasites produce metabolic by-products that suppress RMR. Overall, these findings suggest that impacts of parasites on host energy budgets are complex and are not easily explained by simple effects such as stimulation of a costly immune response. There is currently no broadly generalizable framework available for predicting the energetic consequences of parasitic infection. PMID:17613450

  15. Treatment of fly ash for use in concrete

    Science.gov (United States)

    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.

  16. Treatment of fly ash for use in concrete

    Science.gov (United States)

    Boxley, Chett; Akash, Akash; Zhao, Qiang

    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.

  17. Treatment of fly ash for use in concrete

    Science.gov (United States)

    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.

  18. Sand Flies and Their Control Methods.

    Science.gov (United States)

    Çetin, Hüseyin; Özbel, Yusuf

    2017-06-01

    The main aim of managing arthropod vectors that carry the disease agents is interrupting the infection cycle. Therefore, the management of the disease implies that all precautions related to all elements (i.e., human, arthropod vector, and reservoir) in the infection cycle need to be taken. There are important points that need to be considered while dealing with sand flies (Diptera: Psychodidae: Phlebotominae), which in many regions worldwide, particularly in tropical and subtropical areas, are vectors of diseases such as leishmaniasis and sand fly fever and are the arthropods of the infection cycle. Because the larval control of the sand flies is very difficult and almost impossible, the management is mainly conducted for the adults. The most effective strategy for reducing both sand fly fever and leishmaniasis is managing sand flies, particularly in areas where humans are located. In this review, the morphology, biology, and taxonomy of sand flies; the integrated fighting and management methods such as insecticide-impregnated bed nets and use of curtains, zooprophylaxis, indoor and outdoor residual applications, larvicides, repellents, and insecticide-impregnated dog collars; and data regarding many issues such as insecticide resistance in sand flies have been emphasized on in the review.

  19. Fly ash-reinforced thermoplastic starch composites

    Energy Technology Data Exchange (ETDEWEB)

    Ma, X.F.; Yu, J.G.; Wang, N. [Tianjin University, Tianjin (China). School of Science

    2007-01-02

    As a by-product from the combustion of pulverized coal, fly ash was, respectively, used as the reinforcement for formamide and urea-plasticized thermoplastic starch (FUPTPS) and glycerol-plasticized thermoplastic starch (GPTPS). The introduction of fly ash improved tensile stress from 4.56 MPa to 7.78 MPa and Youngs modulus increased trebly from 26.8 MPa to 84.6 MPa for fly ash-reinforced FUPTPS (A-FUPTPS), while tensile stress increased from 4.55 MPa to 12.86 MPa and Youngs modulus increased six times from 76.4 MPa to 545 MPa for fly ash-reinforced GPTPS (A-GPTPS). X-ray diffractograms illustrated that fly ash destroyed the formation of starch ordered crystal structure, so both A-GPTPS and FUPTPS could resist the starch re-crystallization (retrogradation). Also fly ash improved water resistance of TPS. As shown by rheology, during the thermoplastic processing, the extruder screw speed effectively adjusted the flow behavior of A-FUPTPS, while the increasing of the processing temperature effectively ameliorated the flow behavior of A-GPTPS. However, superfluous ash contents (e.g., 20 wt%) worsened processing fluidity and resulted in the congregation of fly ash in FUPTPS matrix (tested by SEM) rather than in GPTPS matrix. This congregation decreased the mechanical properties and water resistance of the materials.

  20. Marijuana effects on simulated flying ability.

    Science.gov (United States)

    Janowsky, D S; Meacham, M P; Blaine, J D; Schoor, M; Bozzetti, L P

    1976-04-01

    The authors studied the effects of marijuana intoxication on the ability of 10 certified airplane pilots to operate a flight simulator. They used a randomized double-blind crossover design to compare the effect of active versus placebo marijuana. They found that all 10 pilots showed a significant decrease in measurements of flying performance 30 minutes after smoking active marijuana. For a group of 6 pilots tested sequentially for 6 hours, a nonsignificant decrease in flying performance continued for 2 hours after smoking the active drug. The authors conclude that the effects of marijuana on flying performance may represent a sensitive indicator of the drug's psychomotor effects.

  1. Up-regulation of Long Non-coding RNA TUG1 in Hibernating Thirteen-lined Ground Squirrels

    Directory of Open Access Journals (Sweden)

    Jacques J. Frigault

    2016-04-01

    Full Text Available Mammalian hibernation is associated with multiple physiological, biochemical, and molecular changes that allow animals to endure colder temperatures. We hypothesize that long non-coding RNAs (lncRNAs, a group of non-coding transcripts with diverse functions, are differentially expressed during hibernation. In this study, expression levels of lncRNAs H19 and TUG1 were assessed via qRT-PCR in liver, heart, and skeletal muscle tissues of the hibernating thirteen-lined ground squirrels (Ictidomys tridecemlineatus. TUG1 transcript levels were significantly elevated 1.94-fold in skeletal muscle of hibernating animals when compared with euthermic animals. Furthermore, transcript levels of HSF2 also increased 2.44-fold in the skeletal muscle in hibernating animals. HSF2 encodes a transcription factor that can be negatively regulated by TUG1 levels and that influences heat shock protein expression. Thus, these observations support the differential expression of the TUG1–HSF2 axis during hibernation. To our knowledge, this study provides the first evidence for differential expression of lncRNAs in torpid ground squirrels, adding lncRNAs as another group of transcripts modulated in this mammalian species during hibernation.

  2. Fluctuation of Brain Tissue Oxygen Partial Pressure: A Biochemical Landmark in the Arctic Ground Squirrel's Spontaneous Arousal

    Directory of Open Access Journals (Sweden)

    Yi L. Ma

    2011-01-01

    Full Text Available Hibernation in the Arctic ground Squirrel (AGS is a regulated, adaptive response to arctic environmental conditions. Problem statement: Regional brain Blood Flow (rCBF has been observed to increase dramatically during arousal in hibernators. However, the real time dynamic change in PtO2 during arousal has not been studied, we hypothesized that PtO2 is Interdependent of Tbrain and a key component in the arousal process. Approach: Simultaneous in vivo measurements of PtO2 and brain temperature (Tbrain in conjunction with oxygen consumption (V02 were conducted in the striatum of non-sedated, non-anesthetized Arctic ground squirrels during spontaneous arousal from hibernation. Results: A dramatic fluctuation of brain tissue oxygen partial pressure (PtO2 is associated with the complex phenomena of spontaneous arousal. In this study, we observed that: (1 a PtO2 elevation precedes changes in Tbrain and V02; (2 PtO2 changes do not correlate with changes in V02 during arousal and (3, endogenous O2 shift from O2 enriched blood to brain in hibernating AGS induces an arousal with the pharmaceutical chemical, efaproxiral (RSR-13. Conclusion: The four turning points of PtO2 appearing at different Tbrain during arousal suggest that changes in PtO2 are Tbrain interdependent and support the concept that arousal from hibernation is complex process invoking different feedbacks.

  3. Up-regulation of Long Non-coding RNA TUG1 in Hibernating Thirteen-lined Ground Squirrels

    Institute of Scientific and Technical Information of China (English)

    Jacques J. Frigault; Daneck Lang-Ouellette; Pier Morin Jr.

    2016-01-01

    Mammalian hibernation is associated with multiple physiological, biochemical, and molecular changes that allow animals to endure colder temperatures. We hypothesize that long non-coding RNAs (lncRNAs), a group of non-coding transcripts with diverse functions, are differ-entially expressed during hibernation. In this study, expression levels of lncRNAs H19 and TUG1 were assessed via qRT-PCR in liver, heart, and skeletal muscle tissues of the hibernating thirteen-lined ground squirrels (Ictidomys tridecemlineatus). TUG1 transcript levels were signifi-cantly elevated 1.94-fold in skeletal muscle of hibernating animals when compared with euthermic animals. Furthermore, transcript levels of HSF2 also increased 2.44-fold in the skeletal muscle in hibernating animals. HSF2 encodes a transcription factor that can be negatively regulated by TUG1 levels and that influences heat shock protein expression. Thus, these observations support the differential expression of the TUG1–HSF2 axis during hibernation. To our knowledge, this study provides the first evidence for differential expression of lncRNAs in torpid ground squirrels, adding lncRNAs as another group of transcripts modulated in this mammalian species during hibernation.

  4. Very low levels of direct additive genetic variance in fitness and fitness components in a red squirrel population.

    Science.gov (United States)

    McFarlane, S Eryn; Gorrell, Jamieson C; Coltman, David W; Humphries, Murray M; Boutin, Stan; McAdam, Andrew G

    2014-05-01

    A trait must genetically correlate with fitness in order to evolve in response to natural selection, but theory suggests that strong directional selection should erode additive genetic variance in fitness and limit future evolutionary potential. Balancing selection has been proposed as a mechanism that could maintain genetic variance if fitness components trade off with one another and has been invoked to account for empirical observations of higher levels of additive genetic variance in fitness components than would be expected from mutation-selection balance. Here, we used a long-term study of an individually marked population of North American red squirrels (Tamiasciurus hudsonicus) to look for evidence of (1) additive genetic variance in lifetime reproductive success and (2) fitness trade-offs between fitness components, such as male and female fitness or fitness in high- and low-resource environments. "Animal model" analyses of a multigenerational pedigree revealed modest maternal effects on fitness, but very low levels of additive genetic variance in lifetime reproductive success overall as well as fitness measures within each sex and environment. It therefore appears that there are very low levels of direct genetic variance in fitness and fitness components in red squirrels to facilitate contemporary adaptation in this population.

  5. Complementary Network-Based Approaches for Exploring Genetic Structure and Functional Connectivity in Two Vulnerable, Endemic Ground Squirrels

    Directory of Open Access Journals (Sweden)

    Victoria H. Zero

    2017-06-01

    Full Text Available The persistence of small populations is influenced by genetic structure and functional connectivity. We used two network-based approaches to understand the persistence of the northern Idaho ground squirrel (Urocitellus brunneus and the southern Idaho ground squirrel (U. endemicus, two congeners of conservation concern. These graph theoretic approaches are conventionally applied to social or transportation networks, but here are used to study population persistence and connectivity. Population graph analyses revealed that local extinction rapidly reduced connectivity for the southern species, while connectivity for the northern species could be maintained following local extinction. Results from gravity models complemented those of population graph analyses, and indicated that potential vegetation productivity and topography drove connectivity in the northern species. For the southern species, development (roads and small-scale topography reduced connectivity, while greater potential vegetation productivity increased connectivity. Taken together, the results of the two network-based methods (population graph analyses and gravity models suggest the need for increased conservation action for the southern species, and that management efforts have been effective at maintaining habitat quality throughout the current range of the northern species. To prevent further declines, we encourage the continuation of management efforts for the northern species, whereas conservation of the southern species requires active management and additional measures to curtail habitat fragmentation. Our combination of population graph analyses and gravity models can inform conservation strategies of other species exhibiting patchy distributions.

  6. Patterns of ectoparasitism in North American red squirrels (Tamiasciurus hudsonicus: Sex-biases, seasonality, age, and effects on male body condition

    Directory of Open Access Journals (Sweden)

    Jesse E.H. Patterson

    2015-12-01

    Full Text Available Within many species, males are often more heavily parasitised than females. Several hypotheses have been proposed to explain this phenomenon, including immunocompetence handicaps, sexual size dimorphism and behavioural differences. Here we set out to test the latter two hypotheses and make inferences about the former by assessing patterns of ectoparasitism across various life-history stages in a population of North American red squirrels (Tamiasciurus hudsonicus. We also conducted an ectoparasite removal experiment to investigate the effects of ectoparasites on male body condition. We found that males were more intensely parasitized than females, but only during the mating period. There was no difference in ectoparasite intensity between male and female juveniles at birth or at emergence, suggesting that ectoparasites do not exploit male red squirrels for longer-range natal dispersal. Male red squirrels in our population were slightly heavier than females, however we did not find any evidence that this dimorphism drives male-biased ectoparasitism. Finally, we could not detect an effect of ectoparasite removal on male body mass. Our results lend support to the hypothesis that ectoparasites exploit their male hosts for transmission and that male red squirrels are important for the transmission dynamics of ectoparasites in this population; however, the mechanisms (i.e., immunocompetence, testosterone are not known.

  7. Planning a red squirrel conservation area: using a spatially explicit population dynamics model to predict the impact of felling and forest design plans

    NARCIS (Netherlands)

    Lurz, P.W.W.; Geddes, N.; Lloyd, A.J.; Shirley, M.D.E.; Rushton, B.; Burlton, B.

    2003-01-01

    This paper describes the use of a spatially explicit population model (SEPM) to investigate the effects of different forest management strategies on a red squirrel conservation area. The study was based in woodland managed by Forest Enterprise, which manages 75 000 ha of woodlands in Northumberland,

  8. Flying Through Dust From Asteroids

    Science.gov (United States)

    Kohler, Susanna

    2016-11-01

    How can we tell what an asteroid is made of? Until now, weve relied on remote spectral observations, though NASAs recently launched OSIRIS-REx mission may soon change this by landing on an asteroid and returning with a sample.But what if we could learn more about the asteroids near Earth without needing to land on each one? It turns out that we can by flying through their dust.The aerogel dust collector of the Stardust mission. [NASA/JPL/Caltech]Ejected CluesWhen an airless body is impacted by the meteoroids prevalent throughout our solar system, ejecta from the body are flung into the space around it. In the case of small objects like asteroids, their gravitational pull is so weak that most of the ejected material escapes, forming a surrounding cloud of dust.By flying a spacecraft through this cloud, we could perform chemical analysis of the dust, thereby determining the asteroids composition. We could even capture some of the dust during a flyby (for example, by using an aerogel collector like in the Stardust mission) and bring it back home to analyze.So whats the best place to fly a dust-analyzing or -collecting spacecraft? To answer this, we need to know what the typical distribution of dust is around a near-Earth asteroid (NEA) a problem that scientists Jamey Szalay (Southwest Research Institute) and Mihly Hornyi (University of Colorado Boulder) address in a recent study.The colors show the density distribution for dust grains larger than 0.3 m around a body with a 10-km radius. The distribution is asymmetric, with higher densities on the apex side, shown here in the +y direction. [Szalay Hornyi 2016]Moon as a LaboratoryTo determine typical dust distributions around NEAs, Szalay and Hornyi first look at the distribution of dust around our own Moon, caused by the same barrage of meteorites wed expect to impact NEAs. The Moons dust cloud was measured in situ in 2013 and 2014 by the Lunar Dust Experiment (LDEX) on board the Lunar Atmosphere and Dust Environment

  9. Snowballing and flying under the radar

    DEFF Research Database (Denmark)

    Pötz, Katharina Anna; Hjortsø, Carsten Nico Portefée

    2013-01-01

    management and venture development paths. More specifically, flying under radar in terms of operating under lower institutional requirements, and slowly accumulating resources (snowballing) are major leveraging strategies. We integrate our results into a hypothesized framework for resource management in East...

  10. Tsetse fly microbiota: form and function

    Directory of Open Access Journals (Sweden)

    Jingwen eWang

    2013-10-01

    Full Text Available Tsetse flies are the primary vectors of African trypanosomes, which cause Human and Animal African trypanosomiasis in 36 countries in sub-Saharan Africa. These flies have also established symbiotic associations with bacterial and viral microorganisms. Laboratory-reared tsetse flies harbor up to four vertically transmitted organisms - obligate Wigglesworthia, commensal Sodalis, parasitic Wolbachia and Salivary Gland Hypertrophy Virus (SGHV. Field-captured tsetse can harbor these symbionts as well as environmentally acquired commensal bacteria. This microbial community influences several aspects of tsetse’s physiology, including nutrition, fecundity and vector competence. This review provides a detailed description of tsetse’s microbiome, and describes the physiology underlying host-microbe, and microbe-microbe, interactions that occur in this fly.

  11. Dynamic Optimization Algorithm for Flying Trajectory of a Free-flying Space Robot

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new method of dynamic optimization for the flying trajectory of a free-flying space robot based on its flying motion characteristics is presented. The continuous flying trajectory is broken into a number of segment and the control efforts and the duration of the segment are chosen as the optimization parameters. The objective function is made by using the weighted sum of the fuel used and the time spent, and the constraint equations are selected. Finally, the internal point punishment function method is adopted in the optimization program, and the results of computer simulation are given.

  12. Evaluation of Immunocontraception as a Publicly Acceptable Form of Vertebrate Pest Species Control: The Introduced Grey Squirrel in Britain as an Example

    Science.gov (United States)

    Barr, Julian J. F.; Lurz, Peter W. W.; Shirley, Mark D. F.; Rushton, Steve P.

    2002-09-01

    We sent out a targeted questionnaire to organizations and private individuals across the UK that have expressed an interest in squirrel management and conservation. Respondents were asked to evaluate shooting, trapping, poisoning and immunocontraception (IMC), according to their perceived efficacy, cost efficiency, and whether they were considered to be humane. The majority of both professionals and enthusiasts indicated support for grey squirrel control to help conserve red squirrels and to reduce economic damage to timber crops. Respondents' comparative evaluations of current forms of control showed that trapping is the most acceptable method. When IMC is compared with the other methods, it was considered to be more humane and acceptable. In contrast, poisoning was seen as humane or acceptable by the fewest respondents. Furthermore, poisoning elicited the greatest difference in opinion between the professional and enthusiast groups. This difference (34%) may be interpreted partly as concern over the type of death that results from poisoning and partly as due to the possibility of poisoning nontarget species. Our findings indicate a need for more public information regarding secondary poisoning hazards to other species and their predators. Interest and concern about squirrel control correlated with the overlap between contemporary areas of distribution of the two species. It is these areas where consultation and education programs about control methods should be targeted. This research indicates that there would be support for grey squirrel control using IMC from both lay and professional interest groups. It demonstrates the existence of a sound basis for constructive dialog that can lead to the design and implementation of acceptable and efficient control strategies.

  13. Effect of Fly Ash on the Electrical Conductivity of Concretes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The fly ash occasionally has high content of iron oxide and carbon that are good electrical conducting components. This paper investigates the effect of the fly ash used as mineral admixtures on the electrical conductivity of concretes. The electrical properties of concretes using 3 kinds of fly ash with different iron oxide contents have been studied. Experimental results show that at the same fly ash dosage the resistivity of concrete using fly ash with high content of iron oxide is slightly lower than that with low content of iron oxide. However, the concrete resistivity after 14d increases as fly ash dosage increases regardless of iron oxide content in fly ash.

  14. Relativistic Tennis Using Flying Mirror

    Science.gov (United States)

    Pirozhkov, A. S.; Kando, M.; Esirkepov, T. Zh.; Ma, J.; Fukuda, Y.; Chen, L.-M.; Daito, I.; Ogura, K.; Homma, T.; Hayashi, Y.; Kotaki, H.; Sagisaka, A.; Mori, M.; Koga, J. K.; Kawachi, T.; Daido, H.; Bulanov, S. V.; Kimura, T.; Kato, Y.; Tajima, T.

    2008-06-01

    Upon reflection from a relativistic mirror, the electromagnetic pulse frequency is upshifted and the duration is shortened by the factor proportional to the relativistic gamma-factor squared due to the double Doppler effect. We present the results of the proof-of-principle experiment for frequency upshifting of the laser pulse reflected from the relativistic "flying mirror", which is a wake wave near the breaking threshold created by a strong driver pulse propagating in underdense plasma. Experimentally, the wake wave is created by a 2 TW, 76 fs Ti:S laser pulse from the JLITE-X laser system in helium plasma with the electron density of ≈4-6×1019 cm-3. The reflected signal is observed with a grazing-incidence spectrograph in 24 shots. The wavelength of the reflected radiation ranges from 7 to 14 nm, the corresponding frequency upshifting factors are ˜55-115, and the gamma-factors are y = 4-6. The reflected signal contains at least 3×107 photons/sr. This effect can be used to generate coherent high-frequency ultrashort pulses that inherit temporal shape and polarization from the original (low-frequency) ones. Apart from this, the reflected radiation contains important information about the wake wave itself, e.g. location, size, phase velocity, etc.

  15. Biomass fly ash in concrete: Mixture proportioning and mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Shuangzhen Wang; Amber Miller; Emilio Llamazos; Fernando Fonseca; Larry Baxter [Brigham Young University, Provo, UT (USA). Department of Chemical Engineering

    2008-03-15

    ASTM C 618 prohibits use of biomass fly ashes in concrete. This document compares the properties of biomass fly ashes from cofired (herbaceous with coal), pure wood combustion and blended (pure wood fly ash blended with coal fly ash) to those of coal fly ash in concrete. The results illustrate that with 25% replacement (wt%) of cement by fly ash, the compressive strength (one day to one year) and the flexure strength (at 56th day curing) of cofired and blended biomass fly ash concrete is statistically equal to that of two coal fly ash concrete in this investigation (at 95% confidence interval). This implies that biomass fly ash with co-firing concentration within the concentration interest to commercial coal-biomass co-firing operations at power plants and blended biomass fly ash within a certain blending ratio should be considered in concrete. 37 refs., 10 figs., 2 tabs.

  16. My Friendship with the Flying Tigers

    Institute of Scientific and Technical Information of China (English)

    Jiang; Yingshan

    2015-01-01

    "I believe I owe a debt to the Chinese people...It’s so huge there’s no way I can pay it back."This is what Flying Tigers pilot Glen Beneda said to his family time and again.I have been working in the CPAFFC for over 10 years now,and my feelings for the Flying Tigers have deepened over time.I had heard of its

  17. Settling characteristics of some Indian fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Jain, M.K.; Sastry, B.S. [Indian Institute of Technology, Kharapur (India). Dept. of Mining Engineering

    2003-07-01

    The paper examines the aspects of the solid liquid separation (settling characteristics) of some of the fly ash obtained from coal-fired power plants in India. The application of a coagulating or flocculating agent (polymer) to improve the two properties as indicated is a typical industrial practice. The sources for this study comprise of fly ash, pond ash, and bottom ash and the settling characteristics are studied in conjunction with the flocculating agent polyacrylamide. 4 refs., 4 figs., 3 tabs.

  18. As and Se interactions with fly ashes

    Directory of Open Access Journals (Sweden)

    M. Díaz-Somoano

    2012-03-01

    Full Text Available Arsenic and selenium are toxic elements present incoal in trace concentrations that may be emitted tothe environment during coal conversion processes.However, it is possible to retain volatile arsenic andselenium compounds in the fly ashes originated bythe process, the proportions retained depending onthe characteristics of the ashes and processconditions. This work is focused on the capture ofthese elements in fly ashes in simulated coalcombustion and gasification atmospheres inlaboratory scale reactors.

  19. Wolbachia in Anastrepha fruit flies (Diptera: Tephritidae).

    Science.gov (United States)

    Coscrato, Virginia E; Braz, Antônio S K; P Perondini, André L; Selivon, Denise; Marino, Celso L

    2009-09-01

    Endosymbiotic bacteria of the genus Wolbachia are widespread among arthropods and cause a variety of reproductive abnormalities, such as cytoplasmic incompatibility, thelytokous parthenogenesis, male-killing, and host feminization. In this study, we used three sets of Wolbachia-specific primers (16S rDNA, ftsZ, and wsp) in conjunction with the polymerase chain reaction (PCR), cloning and sequencing to study the infection of fruit flies (Anastrepha spp. and Ceratitis capitata) by Wolbachia. The flies were collected at several localities in Brazil and at Guayaquil, Ecuador. All of the fruit flies studied were infected with Wolbachia supergroup A, in agreement with the high prevalence of this group in South America. Phylogenetic analysis showed that the wsp gene was the most sensitive gene for studying the relationships among Wolbachia strains. The Wolbachia sequences detected in these fruit flies were similar to those such as wMel reported for other fruit flies. These results show that the infection of Anastrepha fruit flies by Wolbachia is much more widespread than previously thought.

  20. 76 FR 26654 - Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist

    Science.gov (United States)

    2011-05-09

    ... Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist AGENCY: Animal and... from Mediterranean fruit fly quarantined areas in the United States with a certificate if the fruit is... quarantine regulations to remove trapping requirements for Mediterranean fruit fly for Hass avocados...

  1. Horizontal vestibuloocular reflex evoked by high-acceleration rotations in the squirrel monkey. I. Normal responses

    Science.gov (United States)

    Minor, L. B.; Lasker, D. M.; Backous, D. D.; Hullar, T. E.; Shelhamer, M. J. (Principal Investigator)

    1999-01-01

    The horizontal angular vestibuloocular reflex (VOR) evoked by high-frequency, high-acceleration rotations was studied in five squirrel monkeys with intact vestibular function. The VOR evoked by steps of acceleration in darkness (3,000 degrees /s(2) reaching a velocity of 150 degrees /s) began after a latency of 7.3 +/- 1.5 ms (mean +/- SD). Gain of the reflex during the acceleration was 14.2 +/- 5.2% greater than that measured once the plateau head velocity had been reached. A polynomial regression was used to analyze the trajectory of the responses to steps of acceleration. A better representation of the data was obtained from a polynomial that included a cubic term in contrast to an exclusively linear fit. For sinusoidal rotations of 0.5-15 Hz with a peak velocity of 20 degrees /s, the VOR gain measured 0.83 +/- 0.06 and did not vary across frequencies or animals. The phase of these responses was close to compensatory except at 15 Hz where a lag of 5.0 +/- 0.9 degrees was noted. The VOR gain did not vary with head velocity at 0.5 Hz but increased with velocity for rotations at frequencies of >/=4 Hz (0. 85 +/- 0.04 at 4 Hz, 20 degrees /s; 1.01 +/- 0.05 at 100 degrees /s, P < 0.0001). No responses to these rotations were noted in two animals that had undergone bilateral labyrinthectomy indicating that inertia of the eye had a negligible effect for these stimuli. We developed a mathematical model of VOR dynamics to account for these findings. The inputs to the reflex come from linear and nonlinear pathways. The linear pathway is responsible for the constant gain across frequencies at peak head velocity of 20 degrees /s and also for the phase lag at higher frequencies being less than that expected based on the reflex delay. The frequency- and velocity-dependent nonlinearity in VOR gain is accounted for by the dynamics of the nonlinear pathway. A transfer function that increases the gain of this pathway with frequency and a term related to the third power of head

  2. Arctic ground squirrel neuronal progenitor cells resist oxygen and glucose deprivation-induced death

    Science.gov (United States)

    Drew, Kelly L; Wells, Matthew; McGee, Rebecca; Ross, Austin P; Kelleher-Andersson, Judith

    2016-01-01

    AIM: To investigate the influence of ischemia/reperfusion on arctic ground squirrel (AGS) neuronal progenitor cells (NPCs), we subjected these cultured cells to oxygen and glucose deprivation. METHODS: AGS NPCs were expanded and differentiated into NPCs and as an ischemia vulnerable control, commercially available human NPCs (hNPCs) were seeded from thawed NPCs. NPCs, identified by expression of TUJ1 were seen at 14-21 d in vitro (DIV). Cultures were exposed to control conditions, hypoxia, oxygen and glucose deprivation or glucose deprivation alone or following return to normal conditions to model reperfusion. Cell viability and death were assessed from loss of ATP as well as from measures of alamarBlue® and lactate dehydrogenase in the media and from counts of TUJ1 positive cells using immunocytochemistry. Dividing cells were identified by expression of Ki67 and phenotyped by double labeling with GFAP, MAP2ab or TUJ1. RESULTS: We report that when cultured in NeuraLife™, AGS cells remain viable out to 21 DIV, continue to express TUJ1 and begin to express MAP2ab. Viability of hNPCs assessed by fluorescence alamarBlue (arbitrary units) depends on both glucose and oxygen availability [viability of hNPCs after 24 h oxygen glucose deprivation (OGD) with return of oxygen and glucose decreased from 48151 ± 4551 in control cultures to 43481 ± 2413 after OGD, P < 0.05]. By contrast, when AGS NPCs are exposed to the same OGD with reperfusion at 14 DIV, cell viability assessed by alamarBlue increased from 165305 ± 11719 in control cultures to 196054 ± 13977 after OGD. Likewise AGS NPCs recovered ATP (92766 ± 6089 in control and 92907 ± 4290 after modeled reperfusion; arbitrary luminescence units), and doubled in the ratio of TUJ1 expressing neurons to total dividing cells (0.11 ± 0.04 in control cultures vs 0.22 ± 0.2 after modeled reperfusion, P < 0.05). Maintaining AGS NPCs for a longer time in culture lowered resistance to injury, however, did not impair

  3. The vestibulo-ocular reflex of the squirrel monkey during eccentric rotation and roll tilt

    Science.gov (United States)

    Merfeld, D. M.; Young, L. R.

    1995-01-01

    The vestibulo-ocular reflexes (VOR) are determined not only by angular acceleration, but also by the presence of gravity and linear acceleration. This phenomenon was studied by measuring three-dimensional nystagmic eye movements, with implanted search coils, in six male squirrel monkeys during eccentric rotation. Monkeys were rotated in the dark at a constant velocity of 200 degrees/s (centrally or 79 cm off axis) with the axis of rotation always aligned with gravity and the spinal axis of the upright monkeys. The monkey's orientation (facing-motion or back-to-motion) had a dramatic influence on the VOR. These experiments show that: (a) the axis of eye rotation always shifted toward alignment with gravito-inertial force; (b) the peak value of horizontal slow phase eye velocity was greater with the monkey facing-motion than with back-to-motion; and (c) the time constant of horizontal eye movement decay was smaller with the monkey facing-motion than with back-to-motion. All of these findings were statistically significant and consistent across monkeys. In another set of tests, the same monkeys were rapidly tilted about their naso-occipital (roll) axis. Tilted orientations of 45 degrees and 90 degrees were maintained for 1 min. Other than a compensatory angular VOR during the angular rotation, no consistent eye velocity response was observed during or following the tilt for any of the six monkeys. The absence of any eye movement response following tilt weighs against the possibility that translational linear VOR responses are due to simple high-pass filtering of the otolith signals. The VOR response during eccentric rotation was divided into the more familiar angular VOR and linear VOR components. The angular component is known to depend upon semicircular canal dynamics and central influences. The linear component of the response decays rapidly with a mean duration of only 6.6 s, while the axis of eye rotation rapidly aligns (< 10 s) with gravito-inertial force. These

  4. Intrinsic Membrane Targeting of the Flagellar Export ATPase FliI: Interaction with Acidic Phospholipids and FliH

    OpenAIRE

    Auvray, Frédéric; Ozin, Amanda J.; Claret, Laurent; Hughes, Colin

    2002-01-01

    The specialised ATPase FliI is central to export of flagellar axial protein subunits during flagellum assembly. We establish the normal cellular location of FliI and its regulatory accessory protein FliH in motile Salmonella typhimurium, and ascertain the regions involved in FliH2/FliI heterotrimerisation. Both FliI and FliH localised to the cytoplasmic membrane in the presence and in the absence of proteins making up the flagellar export machinery and basal body. Membrane association was tig...

  5. Direct regulation of BCL-2 by FLI-1 is involved in the survival of FLI-1-transformed erythroblasts

    OpenAIRE

    Lesault, Isabelle; Tran Quang, Christine; Frampton, Jon; Ghysdael, Jacques

    2002-01-01

    Rearrangement of the FLI-1 locus with ensuing overexpression of FLI-1 is an early event in Friend murine leukemia virus-induced disease. When overexpressed in primary erythroblasts, FLI-1 blocks erythropoeitin (Epo)-induced terminal differentiation and inhibits apoptosis normally induced in response to Epo withdrawal. We show here that the survival-inducing property of FLI-1 is associated with increased transcription of BCL-2. We further show that FLI-1 binds BCL-2 promoter sequences in trans...

  6. Expression of defensin paralogs across house fly life history: insights into fly-microbe interactions

    Science.gov (United States)

    House flies have a life-long association with microbe-rich environments. Larvae directly ingest bacteria in decaying substrates utilizing them for nutritional purposes. Adult house flies ephemerally associate with microbes, ingesting them either by direct feeding or indirectly during grooming. The h...

  7. Oral and Topical Toxicity of Fipronil to Melon Fly and Oriental Fruit Fly (Diptera: Tephritidae)

    Science.gov (United States)

    BACKGROUND: The objective of this study was to develop basic oral and topical toxicity data for Fipronil in Solulys protein bait to wild melon fly, Bactrocera cucurbitae (Coquillett) and the oriental fruit fly, Bactrocera dorsalis (Hendel). RESULTS: For the oral study, both females and males were ...

  8. PROBA-3: Precise formation flying demonstration mission

    Science.gov (United States)

    Llorente, J. S.; Agenjo, A.; Carrascosa, C.; de Negueruela, C.; Mestreau-Garreau, A.; Cropp, A.; Santovincenzo, A.

    2013-01-01

    Formation Flying (FF) has generated a strong interest in many space applications, most of them involving a significant complexity for building for example on-board large "virtual structures or distributed observatories". The implementation of these complex formation flying missions with critical dependency on this new, advanced and critical formation technology requires a thorough verification of the system behaviour in order to provide enough guarantees for the target mission success. A significant number of conceptual or preliminary designs, analyses, simulations, and HW on-ground testing have been performed during the last years, but still the limitations of the ground verification determine that enough confidence of the behaviour of the formation flying mission will only be possible by demonstration in flight of the concept and the associated technologies. PROBA-3 is the mission under development at ESA for in-flight formation flying demonstration, dedicated to obtain that confidence and the necessary flight maturity level in the formation flying technologies for those future target missions. PROBA-3 will demonstrate technologies such as formation metrology sensors (from very coarse to highest accuracy), formation control and GNC, system operability, safety, etc. During the last years, PROBA-3 has evolved from the initial CDF study at ESA, to two parallel phase A studies, followed by a change in the industrial configuration for the Bridging step between A and B phases. Currently the SRR consolidation has been completed, and the project is in the middle of the phase B. After the phase A study SENER and GMV were responsible for the Formation Flying System, within a mission core team completed by OHB-Sweden, QinetiQ Space and CASA Espacio. In this paper an overview of the PROBA-3 mission is provided, with a more detailed description of the formation flying preliminary design and results.

  9. Validation of DTI tractography-based measures of primary motor area connectivity in the squirrel monkey brain.

    Directory of Open Access Journals (Sweden)

    Yurui Gao

    Full Text Available Diffusion tensor imaging (DTI tractography provides noninvasive measures of structural cortico-cortical connectivity of the brain. However, the agreement between DTI-tractography-based measures and histological 'ground truth' has not been quantified. In this study, we reconstructed the 3D density distribution maps (DDM of fibers labeled with an anatomical tracer, biotinylated dextran amine (BDA, as well as DTI tractography-derived streamlines connecting the primary motor (M1 cortex to other cortical regions in the squirrel monkey brain. We evaluated the agreement in M1-cortical connectivity between the fibers labeled in the brain tissue and DTI streamlines on a regional and voxel-by-voxel basis. We found that DTI tractography is capable of providing inter-regional connectivity comparable to the neuroanatomical connectivity, but is less reliable measuring voxel-to-voxel variations within regions.

  10. Validation of DTI tractography-based measures of primary motor area connectivity in the squirrel monkey brain.

    Science.gov (United States)

    Gao, Yurui; Choe, Ann S; Stepniewska, Iwona; Li, Xia; Avison, Malcolm J; Anderson, Adam W

    2013-01-01

    Diffusion tensor imaging (DTI) tractography provides noninvasive measures of structural cortico-cortical connectivity of the brain. However, the agreement between DTI-tractography-based measures and histological 'ground truth' has not been quantified. In this study, we reconstructed the 3D density distribution maps (DDM) of fibers labeled with an anatomical tracer, biotinylated dextran amine (BDA), as well as DTI tractography-derived streamlines connecting the primary motor (M1) cortex to other cortical regions in the squirrel monkey brain. We evaluated the agreement in M1-cortical connectivity between the fibers labeled in the brain tissue and DTI streamlines on a regional and voxel-by-voxel basis. We found that DTI tractography is capable of providing inter-regional connectivity comparable to the neuroanatomical connectivity, but is less reliable measuring voxel-to-voxel variations within regions.

  11. Temperature dependence of intracellular free calcium in cardiac myocytes from rat and ground squirrel measured by confocal microscopy

    Institute of Scientific and Technical Information of China (English)

    王世强; 周曾铨; 钱洪

    1999-01-01

    The temperature-dependence of infraeeliular free caleimn (Ca) was investigated in mdo-1 loaded ventricular myocytes from the ral, a non-hibernator, and from the ground squirrel, a hibernator. The dissociation constant of indo-l at different temperatures was calibrated both al pll-tat and at @-stat . and the result demonstrated that the @-stat ralibration should be prettrred . Analysis of the fluoreseent image showed a striking increase of Ca2 as well as spontaneous caleiuni waves in ral cells, indicating an overloaded cakuum. In contrast, cardiac myocytes of the ground sqnirraf were found to keep a constant (Ca2+) without caleium overload regardless of temperature variation. It is be-lieved that understanding of the mechanisms underlying the interccllular caleima homeostasis of hibrernators may lead to solutions of some medical questions .

  12. Sensor-less maximum power point tracking control for wind generation system with squirrel cage induction generator

    Energy Technology Data Exchange (ETDEWEB)

    Senjyu, Tomonobu; Ochi, Yasutaka; Kikunaga, Yasuaki; Tokudome, Motoki; Yona, Atsushi; Muhando, Endusa Billy; Urasaki, Naomitsu [Department of Electrical and Electronics Engineering, Faculty of Engineering, University of the Ryukyus, 1 Senbaru, Nishihara-cho, Nakagami, Okinawa 903-0213 (Japan); Funabashi, Toshihisa [Meidensha Corporation, ThinkPark Tower, 2-1-1, Ohsaki, Shinagawa-ku, Tokyo 141-6029 (Japan)

    2009-04-15

    This paper proposes a technique that determines the optimal windmill operation speed and the optimal rotor flux. Moreover, the position and speed sensor-less wind generation system using the electromotive voltage observer to estimate rotor position and full-order observer to estimate rotor speed and the windmill output torque are proposed. The position and speed sensor-less maximum power point of wind power generation system is controlled by using the above estimated values, optimized windmill operation speed for maximum output power and optimized rotor flux for minimum generator losses. The effectiveness of the position and speed sensor-less maximum power point tracking control for wind power generation system with squirrel cage induction generator is verified by simulations. The simulation results confirm that the proposed method can estimate the operation speed efficiently. (author)

  13. Characteristics of MSWI fly ash during vitrification

    Institute of Scientific and Technical Information of China (English)

    TIAN Shu-lei; WANG Qi; WANG Qun-hui; MA Hong-zhi

    2009-01-01

    The vitrification characteristics of municipal solid waste incinerator (MSWI) fly ash were investigated. Effects of temperature on the binding efficiency of heavy metals, the change of chemical compositions and the weight loss of fly ash in the range of 800 - 1350 ℃ were studied. Toxicity Characteristic Leaching Procedure (TCLP) of the United States was used to analyze the leaching characteristics of heavy metals in fly ash and molten slag. Results indicate that chemical compositions, the weight loss of fly ash and the binding efficiency of heavy metals in fly ash have a tremendous change in the range of 1150 - 1260 ℃. The percentage of CaO, SiO2and AI203 increases with the increasing temperature, whereas it is contrary for SO3 , K2O, Na20 and CI; especially when the temperature is 1260 ℃, the percentage of these four elements decreases sharply from 43.72%to 0. 71%. The weight loss occurs obviously in the range of 1150 - 1260 ℃. Heavy metals of Pb and Cd are almost vaporized above 1000 ℃. Cr is not volatile and its binding efficiency can reach 100% below 1000 ℃. Resuits of TCLP indicate that the heavy metal content of molten slag is beyond stipulated limit values.

  14. Social attraction mediated by fruit flies' microbiome.

    Science.gov (United States)

    Venu, Isvarya; Durisko, Zachary; Xu, Jianping; Dukas, Reuven

    2014-04-15

    Larval and adult fruit flies are attracted to volatiles emanating from food substrates that have been occupied by larvae. We tested whether such volatiles are emitted by the larval gut bacteria by conducting tests under bacteria-free (axenic) conditions. We also tested attraction to two bacteria species, Lactobacillus brevis, which we cultured from larvae in our lab, and L. plantarum, a common constituent of fruit flies' microbiome in other laboratory populations and in wild fruit flies. Neither larvae nor adults showed attraction to axenic food that had been occupied by axenic larvae, but both showed the previously reported attraction to standard food that had been occupied by larvae with an intact microbiome. Larvae also showed significant attraction to volatiles from axenic food and larvae to which we added only either L. brevis or L. plantarum, and volatiles from L. brevis reared on its optimal growth medium. Controlled learning experiments indicated that larvae experienced with both standard and axenic used food do not perceive either as superior, while focal larvae experienced with simulated used food, which contains burrows, perceive it as superior to unused food. Our results suggest that flies rely on microbiome-derived volatiles for long-distance attraction to suitable food patches. Under natural settings, fruits often contain harmful fungi and bacteria, and both L. brevis and L. plantarum produce compounds that suppress the growth of some antagonistic fungi and bacteria. The larval microbiome volatiles may therefore lead prospective fruit flies towards substrates with a hospitable microbial environment.

  15. Investigation of gliding flight by flying fish

    Science.gov (United States)

    Park, Hyungmin; Jeon, Woo-Pyung; Choi, Haecheon

    2006-11-01

    The most successful flight capability of fish is observed in the flying fish. Furthermore, despite the difference between two medium (air and water), the flying fish is well evolved to have an excellent gliding performance as well as fast swimming capability. In this study, flying fish's morphological adaptation to gliding flight is experimentally investigated using dry-mounted darkedged-wing flying fish, Cypselurus Hiraii. Specifically, we examine the effects of the pectoral and pelvic fins on the aerodynamic performance considering (i) both pectoral and pelvic fins, (ii) pectoral fins only, and (iii) body only with both fins folded. Varying the attack angle, we measure the lift, drag and pitching moment at the free-stream velocity of 12m/s for each case. Case (i) has higher lift-to-drag ratio (i.e. longer gliding distance) and more enhanced longitudinal static stability than case (ii). However, the lift coefficient is smaller for case (i) than for case (ii), indicating that the pelvic fins are not so beneficial for wing loading. The gliding performance of flying fish is compared with those of other fliers and is found to be similar to those of insects such as the butterfly and fruitfly.

  16. Opposing activity changes in AMP deaminase and AMP-activated protein kinase in the hibernating ground squirrel.

    Directory of Open Access Journals (Sweden)

    Miguel A Lanaspa

    Full Text Available Hibernating animals develop fatty liver when active in summertime and undergo a switch to a fat oxidation state in the winter. We hypothesized that this switch might be determined by AMP and the dominance of opposing effects: metabolism through AMP deaminase (AMPD2 (summer and activation of AMP-activated protein kinase (AMPK (winter. Liver samples were obtained from 13-lined ground squirrels at different times during the year, including summer and multiples stages of winter hibernation, and fat synthesis and β-fatty acid oxidation were evaluated. Changes in fat metabolism were correlated with changes in AMPD2 activity and intrahepatic uric acid (downstream product of AMPD2, as well as changes in AMPK and intrahepatic β-hydroxybutyrate (a marker of fat oxidation. Hepatic fat accumulation occurred during the summer with relatively increased enzymes associated with fat synthesis (FAS, ACL and ACC and decreased enoyl CoA hydratase (ECH1 and carnitine palmitoyltransferase 1A (CPT1A, rate limiting enzymes of fat oxidation. In summer, AMPD2 activity and intrahepatic uric acid levels were high and hepatic AMPK activity was low. In contrast, the active phosphorylated form of AMPK and β-hydroxybutyrate both increased during winter hibernation. Therefore, changes in AMPD2 and AMPK activity were paralleled with changes in fat synthesis and fat oxidation rates during the summer-winter cycle. These data illuminate the opposing forces of metabolism of AMP by AMPD2 and its availability to activate AMPK as a switch that governs fat metabolism in the liver of hibernating ground squirrel.

  17. Emergence of Cryptosporidium hominis Monkey Genotype II and Novel Subtype Family Ik in the Squirrel Monkey (Saimiri sciureus) in China.

    Science.gov (United States)

    Liu, Xuehan; Xie, Na; Li, Wei; Zhou, Ziyao; Zhong, Zhijun; Shen, Liuhong; Cao, Suizhong; Yu, Xingming; Hu, Yanchuan; Chen, Weigang; Peng, Gangneng

    2015-01-01

    A single Cryptosporidium isolate from a squirrel monkey with no clinical symptoms was obtained from a zoo in Ya'an city, China, and was genotyped by PCR amplification and DNA sequencing of the small-subunit ribosomal RNA (SSU rRNA), 70-kDa heat shock protein (HSP70), Cryptosporidium oocyst wall protein, and actin genes. This multilocus genetic characterization determined that the isolate was Cryptosporidium hominis, but carried 2, 10, and 6 nucleotide differences in the SSU rRNA, HSP70, and actin loci, respectively, which is comparable to the variations at these loci between C. hominis and the previously reported monkey genotype (2, 3, and 3 nucleotide differences). Phylogenetic studies, based on neighbor-joining and maximum likelihood methods, showed that the isolate identified in the current study had a distinctly discordant taxonomic status, distinct from known C. hominis and also from the monkey genotype, with respect to the three loci. Restriction fragment length polymorphisms of the SSU rRNA gene obtained from this study were similar to those of known C. hominis but clearly differentiated from the monkey genotype. Further subtyping was performed by sequence analysis of the gene encoding the 60-kDa glycoprotein (gp60). Maximum homology of only 88.3% to C. hominis subtype IdA10G4 was observed for the current isolate, and phylogenetic analysis demonstrated that this particular isolate belonged to a novel C. hominis subtype family, IkA7G4. This study is the first to report C. hominis infection in the squirrel monkey and, based on the observed genetic characteristics, confirms a new C. hominis genotype, monkey genotype II. Thus, these results provide novel insights into genotypic variation in C. hominis.

  18. Metabolic hormone FGF21 is induced in ground squirrels during hibernation but its overexpression is not sufficient to cause torpor.

    Directory of Open Access Journals (Sweden)

    Bethany T Nelson

    Full Text Available Hibernation is a natural adaptation that allows certain mammals to survive physiological extremes that are lethal to humans. Near freezing body temperatures, heart rates of 3-10 beats per minute, absence of food consumption, and depressed metabolism are characteristic of hibernation torpor bouts that are periodically interrupted by brief interbout arousals (IBAs. The molecular basis of torpor induction is unknown, however starved mice overexpressing the metabolic hormone fibroblast growth factor 21 (FGF21 promote fat utilization, reduce body temperature, and readily enter torpor-all hallmarks of mammalian hibernation. In this study we cloned FGF21 from the naturally hibernating thirteen-lined ground squirrel (Ictidomys tridecemlineatus and found that levels of FGF21 mRNA in liver and FGF21 protein in serum are elevated during hibernation torpor bouts and significantly elevated during IBAs compared to summer active animals. The effects of artificially elevating circulating FGF21 concentrations 50 to 100-fold via adenoviral-mediated overexpression were examined at three different times of the year. This is the first time that a transgenic approach has been used in a natural hibernator to examine mechanistic aspects of hibernation. Surgically implanted transmitters measured various metrics of the hibernation phenotype over a 7-day period including changes in motor activity, heart rate and core body temperature. In April fed-state animals, FGF21 overexpression decreased blood insulin and free fatty acid concentrations, effects similar to those seen in obese mice. However, elevated FGF21 concentrations did not cause torpor in these fed-state animals nor did they cause torpor or affect metabolic parameters in fasted-state animals in March/April, August or October. We conclude that FGF21 is strongly regulated during torpor and IBA but that its overexpression is not sufficient to cause torpor in naturally hibernating ground squirrels.

  19. Activity budget, diet, and use of space by two groups of squirrel monkeys (Saimiri sciureus) in eastern Amazonia.

    Science.gov (United States)

    Pinheiro, Tatyana; Ferrari, Stephen F; Lopes, Maria Aparecida

    2013-07-01

    Squirrel monkeys (Saimiri spp.) are widely distributed in the Amazon basin. This study describes the ecological and behavioral patterns of two social groups of S. sciureus in forests adjacent to the Tucuruí hydroelectric reservoir in eastern Amazonia, including range size, activity budgets, and composition of the diet. The groups were monitored at Base 4 (group B4) and Germoplasma Island (group GI). Quantitative behavioral data were collected using instantaneous scan sampling to record behavior, substrate use, and height. Home ranges were delimited using a GPS to determine group position after each 50 m of movement. Home ranges were 75.0 ha for group B4 (39 members) and 77.5 ha for group GI (32 members). The use of vertical strata was well defined, with a marked preference for the middle and lower levels of the canopy. The activity budgets of both groups were typical of those of other squirrel monkeys and were dominated by foraging (B4 = 48.7 %; GI = 49.6 %), moving (both groups 28.9 %), and feeding (B4 = 14.6 %; GI = 12.4 %). Resting was rare (B4 = 3.5 %; GI = 2.6 %) and less common than social behavior (B4 = 4.3 %; GI = 6.4 %). The diet of both groups was dominated by plant material (B4 = 70.7 % of feeding records; GI = 71.4 %), which is in contrast with the more insectivorous diets recorded for Saimiri at other sites. Group GI spent more time foraging during the dry season, whereas group B4 spent more time in the rainy season when the consumption of fruit increased (significantly, in the case of group GI). The less insectivorous diet of these groups may be due to a number of factors, including the unique habitat configuration at the site and reduced hydrological stress due to the proximity of the reservoir.

  20. FlyBase: improvements to the bibliography.

    Science.gov (United States)

    Marygold, Steven J; Leyland, Paul C; Seal, Ruth L; Goodman, Joshua L; Thurmond, Jim; Strelets, Victor B; Wilson, Robert J

    2013-01-01

    An accurate, comprehensive, non-redundant and up-to-date bibliography is a crucial component of any Model Organism Database (MOD). Principally, the bibliography provides a set of references that are specific to the field served by the MOD. Moreover, it serves as a backbone to which all curated biological data can be attributed. Here, we describe the organization and main features of the bibliography in FlyBase (flybase.org), the MOD for Drosophila melanogaster. We present an overview of the current content of the bibliography, the pipeline for identifying and adding new references, the presentation of data within Reference Reports and effective methods for searching and retrieving bibliographic data. We highlight recent improvements in these areas and describe the advantages of using the FlyBase bibliography over alternative literature resources. Although this article is focused on bibliographic data, many of the features and tools described are applicable to browsing and querying other datasets in FlyBase.

  1. Attracting the attention of a fly.

    Science.gov (United States)

    Sareen, Preeti; Wolf, Reinhard; Heisenberg, Martin

    2011-04-26

    Organisms with complex visual systems rarely respond to just the sum of all visual stimuli impinging on their eyes. Often, they restrict their responses to stimuli in a temporarily selected region of the visual field (selective visual attention). Here, we investigate visual attention in the fly Drosophila during tethered flight at a torque meter. Flies can actively shift their attention; however, their attention can be guided to a certain location by external cues. Using visual cues, we can direct the attention of the fly to one or the other of the two visual half-fields. The cue can precede the test stimulus by several seconds and may also be spatially separated from the test by at least 20° and yet attract attention. This kind of external guidance of attention is found only in the lower visual field.

  2. Pigments of fly agaric (Amanita muscaria).

    Science.gov (United States)

    Stintzing, Florian; Schliemann, Willibald

    2007-01-01

    The complex pigment pattern of fly agaric (Amanita muscaria) cap skins has been studied by LC-DAD and mass spectrometry. Among the betaxanthins the corresponding derivatives of serine, threonine, ethanolamine, alanine, Dopa, phenylalanine and tryptophan are reported for the first time to contribute to the pigment pattern of fly agarics. Betalamic acid, the chromophoric precursor of betaxanthins and betacyanins, muscaflavin and seco-dopas were also detected. Furthermore, the red-purple muscapurpurin and the red muscarubrin were tentatively assigned while further six betacyanin-like components could not be structurally allocated. Stability studies indicated a high susceptibility of pigment extracts to degradation which led to rapid colour loss thus rendering a complete characterization of betacyanin-like compounds impossible at present. Taking into account these difficulties the presented results may be a starting point for a comprehensive characterization of the pigment composition of fly agarics.

  3. Research on Partner-fly Infrared Decoys

    Institute of Scientific and Technical Information of China (English)

    HONG Yang; LI Yan-jun; WANG Qi

    2006-01-01

    With the rapid development of new generation of infrared-guided missiles, it is very difficult for the traditional point-source infrared decoys to confront them. Therefore it is important to research the jamming mechanism and tactical application of infrared decoys. Through the research on rocket-propelled infrared decoys, a movement model and a radiation pattern of partner-fly infrared decoy are established based on the jamming mechanism of infrared centroid effect, the aerodynamics principle as well as the aeronautical dynamics principle. A dynamic simulation seeking superiority is conducted for its firing range and direction, a tactical application method of partner-fly infrared decoy against infrared-guided missile is explored, and the technical conditions of partner-fly infrared decoys are determined.

  4. Discriminating fever behavior in house flies.

    Directory of Open Access Journals (Sweden)

    Robert D Anderson

    Full Text Available Fever has generally been shown to benefit infected hosts. However, fever temperatures also carry costs. While endotherms are able to limit fever costs physiologically, the means by which behavioral thermoregulators constrain these costs are less understood. Here we investigated the behavioral fever response of house flies (Musca domestica L. challenged with different doses of the fungal entomopathogen, Beauveria bassiana. Infected flies invoked a behavioral fever selecting the hottest temperature early in the day and then moving to cooler temperatures as the day progressed. In addition, flies infected with a higher dose of fungus exhibited more intense fever responses. These variable patterns of fever are consistent with the observation that higher fever temperatures had greater impact on fungal growth. The results demonstrate the capacity of insects to modulate the degree and duration of the fever response depending on the severity of the pathogen challenge and in so doing, balance the costs and benefits of fever.

  5. A Novel Method for Tracking Individuals of Fruit Fly Swarms Flying in a Laboratory Flight Arena.

    Science.gov (United States)

    Cheng, Xi En; Qian, Zhi-Ming; Wang, Shuo Hong; Jiang, Nan; Guo, Aike; Chen, Yan Qiu

    2015-01-01

    The growing interest in studying social behaviours of swarming fruit flies, Drosophila melanogaster, has heightened the need for developing tools that provide quantitative motion data. To achieve such a goal, multi-camera three-dimensional tracking technology is the key experimental gateway. We have developed a novel tracking system for tracking hundreds of fruit flies flying in a confined cubic flight arena. In addition to the proposed tracking algorithm, this work offers additional contributions in three aspects: body detection, orientation estimation, and data validation. To demonstrate the opportunities that the proposed system offers for generating high-throughput quantitative motion data, we conducted experiments on five experimental configurations. We also performed quantitative analysis on the kinematics and the spatial structure and the motion patterns of fruit fly swarms. We found that there exists an asymptotic distance between fruit flies in swarms as the population density increases. Further, we discovered the evidence for repulsive response when the distance between fruit flies approached the asymptotic distance. Overall, the proposed tracking system presents a powerful method for studying flight behaviours of fruit flies in a three-dimensional environment.

  6. A Novel Method for Tracking Individuals of Fruit Fly Swarms Flying in a Laboratory Flight Arena.

    Directory of Open Access Journals (Sweden)

    Xi En Cheng

    Full Text Available The growing interest in studying social behaviours of swarming fruit flies, Drosophila melanogaster, has heightened the need for developing tools that provide quantitative motion data. To achieve such a goal, multi-camera three-dimensional tracking technology is the key experimental gateway. We have developed a novel tracking system for tracking hundreds of fruit flies flying in a confined cubic flight arena. In addition to the proposed tracking algorithm, this work offers additional contributions in three aspects: body detection, orientation estimation, and data validation. To demonstrate the opportunities that the proposed system offers for generating high-throughput quantitative motion data, we conducted experiments on five experimental configurations. We also performed quantitative analysis on the kinematics and the spatial structure and the motion patterns of fruit fly swarms. We found that there exists an asymptotic distance between fruit flies in swarms as the population density increases. Further, we discovered the evidence for repulsive response when the distance between fruit flies approached the asymptotic distance. Overall, the proposed tracking system presents a powerful method for studying flight behaviours of fruit flies in a three-dimensional environment.

  7. Changeing of fly ash leachability after grinding

    Science.gov (United States)

    Lakatos, J.; Szabo, R.; Racz, A.; Banhidi, O.; Mucsi, G.

    2016-04-01

    Effect of grinding on the reactivity of fly ash used for geopolymer production was tested. Extraction technique using different alkaline and acidic solutions were used for detect the change of the solubility of elements due to the physical and mechano-chemical transformation of minerals in function of grinding time. Both the extraction with alkaline and acidic solution have detected improvement in solubility in function of grinding time. The enhancement in alkaline solution was approx. 100% in case of Si and Al. The acidic medium able to dissolve the fly ash higher manner than the alkaline, therefore the effect of grinding was found less pronounced.

  8. How mosquitoes fly in the rain

    Science.gov (United States)

    Dickerson, Andrew; Shankles, Peter; Madhavan, Nihar; Hu, David

    2011-11-01

    Mosquitoes thrive during rainfall and high humidity. If raindrops are 50 times heavier than mosquitoes, how do mosquitoes fly in the rain? In this combined experimental and theoretical study, we measure the impact force between a falling drop and a free-flying mosquito. High-speed videography of mosquitoes and custom-built mimics reveals a mosquito's low inertia renders it impervious to falling drops. Drops do not splash on mosquitoes, but simply push past them allowing a mosquito to continue on its flight path undeterred. We rationalize the force imparted using scaling relations based on the time of rebound between a falling drop and a free body of significantly less mass.

  9. Physical cleaning of high carbon fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Gray, McMahan L.; Champagne, Kenneth J.; Soong, Yee; Killmeyer, Richard P. [National Energy Technology Laboratory, US Department of Energy, P.O. Box 10940, Cochran Mills Roads, 15236 Pittsburgh, PA (United States); Maroto-Valer, M. Mercedes; Andresen, John M. [The Energy Institute, The Pennsylvania State University, 405 Academic Activities Building, 16802-2308 University Park, PA (United States); Ciocco, Michael V.; Zandhuis, Paul H. [Parson Project Services Inc, National Energy Technology Laboratory, P.O. Box 618, 15129 Library, Pittsburgh, PA (United States)

    2002-04-20

    An industrial fly ash sample was cleaned by three different processes, which were triboelectrostatic separation, ultrasonic column agglomeration, and column flotation. The unburned carbon concentrates were collected at purities ranging up to 62% at recoveries of 62%. In addition, optical microscopy studies were conducted on the final carbon concentrates to determine the carbon forms (inertinite, isotropic coke and anisotropic coke) collected from these various physical-cleaning processes. The effects of the various cleaning processes on the production of different carbon forms from high carbon fly ashes will be discussed.

  10. A FLYING WIRE SYSTEM IN THE AGS.

    Energy Technology Data Exchange (ETDEWEB)

    HUANG,H.; BUXTON,W.; MAHLER,G.; MARUSIC,A.; ROSER,T.; SMITH,G.; SYPHERS,M.; WILLIAMS,N.; WITKOVER,R.

    1999-03-29

    As the AGS prepares to serve as the injector for RHIC, monitoring and control of the beam transverse emittance become a major and important topic. Before the installation of the flying wire system, the emittance was measured with ionization profile monitors in the AGS, which require correction for space charge effects. It is desirable to have a second means of measuring profile that is less depend on intensity. A flying wire system has been installed in the AGS recently to perform this task. This paper discusses the hardware and software setup and the capabilities of the system.

  11. Green tree frog (Hyla cinerea) and ground squirrel (Xerospermophilus spilosoma) mortality attributed to inland brevetoxin transportation at Padre Island National Seashore, Texas, 2015

    Science.gov (United States)

    Buttke, Danielle E.; Walker, Alicia; Huang, I-Shuo; Flewelling, Leanne; Lankton, Julia S.; Ballmann, Anne E.; Clapp, Travis; Lindsay, James; Zimba, Paul V.

    2017-01-01

    On 16 September 2015, a red tide (Karenia brevis) bloom impacted coastal areas of Padre Island National Seashore Park. Two days later and about 0.9 km inland, 30–40 adult green tree frogs (Hyla cinerea) were found dead after displaying tremors, weakness, labored breathing, and other signs of neurologic impairment. A rainstorm, accompanied by high winds, rough surf, and high tides, which could have aerosolized brevetoxin, occurred on the morning of the mortality event. Frog carcasses were healthy but contained significant brevetoxin in tissues. Tissue brevetoxin was also found in two dead or dying spotted ground squirrels (Xerospermophilus spilosoma) and a coyote (Canis latrans). Rainwater collected from the location of the mortality event contained brevetoxin. Mortality of green tree frog and ground squirrel mortality has not been previously attributed to brevetoxin exposure and such mortality suggested that inland toxin transport, possibly through aerosols, rainfall, or insects, may have important implications for coastal species.

  12. [Influence of ionizing radiation on the condition of the protein-synthesizing system in ground squirrel brain neurons at different functional states].

    Science.gov (United States)

    Gordon, R Ia; Ignat'ev, D A; Mel'nikova, E V; Rogachevskaĭ, V V; Kraev, I V; Khutsian, S S

    2006-01-01

    It was shown by fluorescent and electron microscopy that the physiological state of ground squirrels subjected to ionizing radiation at different phases of the torpor-normothermia cycle plays a determining role in the alteration of the conditions of the protein-synthesizing system in neurons of hippocampus fields CA1 and CA3 and sensomotor area of the brain. In ground squirrels irradiated under normothermia, the neurons were less radioresistant and restored slower compared with torpor animal cells, the distinctions being most expressed in CA1 field neurons. The effect of irradiation was minimum during the entrance into torpor and maximum during arousal. It was supposed that the inhibition of protein synthesis in the latter case occurred at the elongation stage when heavy polyribosomes were formed in neuron cytoplasm.

  13. Immunoreactivities of androgen receptor, estrogen receptors, p450arom, p450c17 proteins in wild ground squirrels ovaries during the nonbreeding and breeding seasons

    Directory of Open Access Journals (Sweden)

    Li Xiaonan

    2012-09-01

    Full Text Available Abstract The aim of this study was to elucidate the regulatory role of androgen in the follicular development of wild female ground squirrels. Immunohistochemical staining of FSHR, LHR, P450c17, P450arom, androgen receptor (AR, estrogen receptors (ERa and ERb were executed in ovaries of female ground squirrels from both breeding and nonbreeding seasons. In addition, total ovarian proteins were extracted from the ovaries of squirrels from breeding and nonbreeding seasons, and Western blot analysis were performed in order to probe for FSHR, LHR, P450c17, P450arom, AR, ERa and ERb. The results of immunohistochemical staining and Western blotting of P450c17 showed that there was no significant difference between the breeding and nonbreeding seasons. It was found that granulosa cells expressed P450arom during the breeding season. In contrast, there was no positive staining of P450arom in the nonbreeding season. There was no significant difference in immunoreactivity of AR between the breeding and nonbreeding seasons. However, the immunoreactivities of ERa and ERb were both significantly reduced in the nonbreeding season compared to the breeding season. The positive stains of FSHR and LHR were found in the granulosa cells and theca cells of the ovaries of the breeding and nonbreeding seasons. In addition, the Western blotting results of FSHR and LHR showed a significant reduction in the nonbreeding season compared with the breeding season. These findings suggested that androgen might be predominantly converted into estrogen in order to regulate the follicular development via binding of estrogen receptors during the breeding season, whereas androgen might predominantly directly bind androgen receptor to regulate the follicular development during the nonbreeding season in the ovaries of wild female ground squirrels.

  14. 关于鼠笼硬质跳线制作工艺的探讨%On the Production Process of Squirrel Cage Hard Jumping Wire

    Institute of Scientific and Technical Information of China (English)

    谈朝霞

    2012-01-01

      阐述了引流跳线安装是架空输电线路附件安装的重要组成部分,跳线安装位置的准确性、美观性直接影响输电线路工程的施工工艺,鼠笼硬质跳线安装的关键主要从准备工作、钢管架安装、鼠笼箍架吊装、工艺控制等方面加以控制。探讨了输电线路工程架线施工中鼠笼硬跳线的安装方法,并对鼠笼硬跳线安装工艺的控制难点、要点进行了分析。%  The installation of drainage jumper wire is an important part of attachment installation in the process of transmission line stringing construction work. Accuracy and beauty of the position of jumping wire have direct influence on the construction process in the transmission line project. The installation of squirrel cage hard jumping wire is mainly controlled from the preparation,steel frame installation,hoisting of squirrel cage hoop frame,process control and etc. . This paper introduces the installation methods of squirrel cage hard jumping wire in the process of transmission line stringing construction,and also analyzes the control points in the installation of the squirrel cage hard jumping wires.

  15. Some aspects of the ecology of the Indian Giant Squirrel Ratufa indica (Erxleben, 1777 in the tropical forests of Mudumalai Wildlife Sanctuary, southern India and their conservation implications

    Directory of Open Access Journals (Sweden)

    N. Baskaran

    2011-07-01

    Full Text Available The Indian Giant Squirrel Ratufa indica, an endemic species to India, is widely distributed from the evergreen to moist and dry deciduous forests of Western and Eastern Ghats and the central Indian hills. We studied its population distribution, activity, feeding, ranging and nesting behaviour across three major habitats in the tropical forests of Mudumalai Wildlife Sanctuary, southern India, during 1998-2000 to manage the species effectively. Extensive survey of the three major habitats—tropical moist, dry deciduous and dry thorn—in the sanctuary shows that its distribution is continuous in moist and dry deciduous forests with good canopy contiguity and patchy along riverine areas in dry thorn and dry deciduous forests with sparse trees and broken canopy. Density estimates using 55 direct sightings from 199 km line transects show a mean of 2.9 (plus or minus 0.313 squirrels/km2. Daylight activity and feeding patterns assessed through 24,098 minutes of focal sampling reveal that animals feed and rest equal amounts of time. The diet constitutes seeds, bark, petioles, leaves and fruits from 25 plants, with Tectona grandis as the principal food source (41%. Its home range size varied from 0.8-1.7 ha with a mean of 1.3ha. Nesting characteristics assessed through 83 nests surveyed along 54km transects showed that the squirrel uses 15 of the 33 tree species found, with higher preference to Schleichera oleosa and Mangifera indica. Nest trees are significantly larger in height, gbh and canopy contiguity than nearest non-nest trees, which are attributed to better protection and escape from predators. Maintenance of diverse natural habitats and reduction in anthropogenic pressure are measures suggested for the conservation of giant squirrel populations in the study area.

  16. The expression of leptin, hypothalamic neuropeptides and UCP1 before, during and after fattening in the Daurian ground squirrel (Spermophilus dauricus).

    Science.gov (United States)

    Xing, Xin; Yang, Ming; Wang, De-Hua

    2015-06-01

    The Daurian ground squirrel (Spermophilus dauricus) accumulates large amounts of body fat during pre-hibernation fattening. Leptin, an adipose-derived hormone, plays important roles in energy balance and thermogenesis. We predicted that body fat accumulation would lead to the elevation of leptin concentration while its effect on satiety would be suppressed in hypothalamus during fattening. In addition, the uncoupling protein 1 (UCP1) in brown adipose tissue (BAT) would increase and correlated positively with leptin concentration before hibernation. Here, we measured serum leptin concentration and leptin mRNA in white adipose tissue (WAT), hypothalamic neuropeptides involved in energy regulation and UCP1 in BAT before, during and after fattening in squirrels. The fat mass gradually increased during fattening but serum leptin increased mainly in the late phase of fattening, which was consistent with leptin mRNA expression in WAT. During fattening, the mRNA of hypothalamic leptin receptor was up-regulated and correlated positively with serum leptin. Orexigenic neuropeptide Y mRNA increased by 67%; however agouti-related peptide remained unchanged before hibernation. There was no significant change in anorexigenic neuropeptide mRNA. No change in suppressor of cytokine signaling-3 and protein tyrosine phosphatase-1B was detected. UCP1 mRNA expression and protein content in BAT increased significantly after fattening. These changes were independent of environmental conditions and serum leptin concentration. Our results suggest that the dissociation of leptin production and adiposity during fattening may facilitate fat accumulation. No evidence of suppressed leptin signal was found in fattening squirrels. The UCP1 recruitment in post-fattening squirrels could occur without winter-like acclimation and increased leptin.

  17. Eco-friendly fly ash utilization: potential for land application

    Energy Technology Data Exchange (ETDEWEB)

    Malik, A.; Thapliyal, A. [Indian Institute of Technology Delhi, New Delhi (India)

    2009-07-01

    The increase in demand for power in domestic, agricultural, and industrial sectors has increased the pressure on coal combustion and aggravated the problem of fly ash generation/disposal. Consequently the research targeting effective utilization of fly ash has also gained momentum. Fly ash has proved to be an economical substitute for expensive adsorbents as well as a suitable raw material for brick manufacturing, zeolite synthesis, etc. Fly ash is a reservoir of essential minerals but is deficient in nitrogen and phosphorus. By amending fly ash with soil and/or various organic materials (sewage sludge, bioprocess materials) as well as microbial inoculants like mycorrhizae, enhanced plant growth can be realized. Based on the sound results of large scale studies, fly ash utilization has grown into prominent discipline supported by various internationally renowned organizations. This paper reviews attempts directed toward various utilization of fly ash, with an emphasis on land application of organic/microbial inoculants amended fly ash.

  18. Seasonal changes of androgen receptor, estrogen receptors and aromatase expression in the medial preoptic area of the wild male ground squirrels (Citellus dauricus Brandt

    Directory of Open Access Journals (Sweden)

    F. Zhang

    2016-05-01

    Full Text Available The wild ground squirrel is a typical seasonal breeder. In this study, using RT-PCR, western blot and immunohistochemistry, we investigated the mRNA and protein expressions of androgen receptor (AR, estrogen receptors α and β (ERα and ERβ and aromatase cytochrome P450 (P450arom in the medial preoptic area (MPOA of hypothalamus of the wild male ground squirrel during the breeding season (April, the non-breeding season (June and pre-hibernation (September. AR, ERα, ERβ and P450arom protein/mRNA were present in the MPOA of all seasons detected. The immunostaining of AR and ERα showed no significant changes in different periods, whereas ERβ and P450arom had higher immunoreactivities during the breeding season and pre-hibernation when compared to those of the non-breeding season. Consistently, both the protein and mRNA levels of P450arom and ERβ were higher in the MPOA of pre-hibernation and the breeding season than in the non-breeding season, whereas no significant difference amongst the three periods was observed for AR and ERα levels. These findings suggested that the MPOA of hypothalamus may be a direct target of androgen and estrogen. Androgen may play important regulatory roles through its receptor and/or the aromatized estrogen in the MPOA of hypothalamus of the wild male ground squirrels.

  19. A new site record of the Grizzled Giant Squirrel Ratufa macroura (Pennant, 1769 in the Hosur forest division, Eastern Ghats, India and its conservation significance

    Directory of Open Access Journals (Sweden)

    N. Baskaran

    2011-06-01

    Full Text Available The Grizzled Giant Squirrel is endemic to southern India and Sri Lanka. In India it is distributed in isolated populations with less than 500 mature individuals, restricted mostly to patchy riverine habitats. We have recorded the presence of this species (minimum 14 individuals across eight locations in Hosur forest division along the Cauvery riverine forest, north of earlier reported locations in the Eastern Ghats. The documentation of this species in the study area adds to our understanding of its distribution. These squirrels are canopy dwellers, hence discontinuous forest restricts their movement and dispersal. Measures including stop auctioning Tamarindus indica fruits on large scale for commercial purpose by Forest Department, restoration of habitat, maintenance of canopy continuity, reducing anthropogenic pressure and translocating squirrels from larger populations are suggested to enhance the long-term survival of this habitat specialist, which is on the brink of local extinction in the study area. We also suggest a comprehensive population assessment of the species to reevaluate its global status.

  20. Four Hour Temporal Relation of 5-HTP and L-DOPA Induces Inhibitory Responses in Recrudescing Gonad of Indian Palm Squirrel (Funambulus pennantii).

    Science.gov (United States)

    Jaiwal, Ranjana; Chaturvedi, C M

    2013-01-01

    Daily injections of L-dihydroxyphenylalanine (L-DOPA, dopamine precursor) given 4 h after 5-hydroxytryptophan (5-HTP, serotonin precursor) induced inhibitory responses in recrudescing gonad (in the first week of December) of Indian palm squirrel, a seasonally breeding subtropical animal. Other temporal relations (L-DOPA given at 0, 8, 12, 16, and 20 h after 5-HTP administration) did not show any effect on the recrudescing gonad. This inhibitory effect of 4 h was evident under short day length (6 : 18) group but was masked by the increasing day length of nature (NDL, late December onwards) and increased photoperiod of long day group (16 : 8). It is apparent that seasonal testicular recrudescence of Indian palm squirrel during short day length by 4 h relation of 5-HTP and L-DOPA is not a pharmacological effect but actually is an alteration of seasonality in this annually breeding mammal. It seems that endogenous mechanism controlling seasonal testicular recrudescence of Indian palm squirrel is reset by timed daily injections of these neurotransmitter drugs. It is suggested that in spite of different environmental factors (photoperiod, humidity, etc.) used by different species to time their annual reproduction, basic mechanism of seasonality appears to be the same, that is, the temporal synergism of neurotransmitter activity.

  1. Immunolocalization of NGF and its receptors in ovarian surface epithelium of the wild ground squirrel during the breeding and nonbreeding seasons.

    Science.gov (United States)

    Bao, L; Li, Q; Liu, Y; Li, B; Sheng, X; Han, Y; Weng, Q

    2014-05-09

    The ovarian surface epithelium (OSE) plays an important role in normal ovarian physiology. During each reproductive cycle, the OSE takes part in the cyclical ovulatory ruptures and repair. The aim of this study was to investigate the immunolocalization of nerve growth factor (NGF) and its receptors, tyrosine kinase A (TrkA) and p75, in the OSE cells of the wild ground squirrels during the breeding and nonbreeding seasons. There were marked variations in ovarian weight and size between the breeding and the nonbreeding seasons. Histologically, cuboidal cells and squamous cells were identified in the OSE of both seasons. Yet, stronger immunostaining of NGF, TrkA and p75 were observed in cuboidal cells and squamous cells in the breeding season as compared to the nonbreeding season. In addition, plasma gonadotropin concentrations were higher in the breeding season than in the nonbreeding season, suggesting that the expression patterns of NGF, TrkA and p75 in the OSE were correlated with changes in plasma gonadotropins. These findings suggested that NGF and its receptor TrkA and p75 may be involved in the regulation of seasonal changes in the OSE of wild ground squirrel.in the OSE of wild ground squirrel.

  2. Groundwater quality, age, and susceptibility and vulnerability to nitrate contamination with linkages to land use and groundwater flow, Upper Black Squirrel Creek Basin, Colorado, 2013

    Science.gov (United States)

    Wellman, Tristan P.; Rupert, Michael G.

    2016-03-03

    The Upper Black Squirrel Creek Basin is located about 25 kilometers east of Colorado Springs, Colorado. The primary aquifer is a productive section of unconsolidated deposits that overlies bedrock units of the Denver Basin and is a critical resource for local water needs, including irrigation, domestic, and commercial use. The primary aquifer also serves an important regional role by the export of water to nearby communities in the Colorado Springs area. Changes in land use and development over the last decade, which includes substantial growth of subdivisions in the Upper Black Squirrel Creek Basin, have led to uncertainty regarding the potential effects to water quality throughout the basin. In response, the U.S. Geological Survey, in cooperation with Cherokee Metropolitan District, El Paso County, Meridian Service Metropolitan District, Mountain View Electric Association, Upper Black Squirrel Creek Groundwater Management District, Woodmen Hills Metropolitan District, Colorado State Land Board, and Colorado Water Conservation Board, and the stakeholders represented in the Groundwater Quality Study Committee of El Paso County conducted an assessment of groundwater quality and groundwater age with an emphasis on characterizing nitrate in the groundwater.

  3. Lixiviation of fly ash. Uitloging van vliegas

    Energy Technology Data Exchange (ETDEWEB)

    Verhagen, L.

    1988-01-01

    The lixiviation of a number of elements (Na, K, Ca, Mg, V, As, Sb and Hg) from different fly ash products (fired and cement bounded products) is investigated. A theoretical description of diffusion from a fly ash product is given as well as a standard test to determine the lixiviation rate. Lixiviation can be interpreted as a diffusion process. Diffusion of an element X from a fly ash product can be described with the following parameters: the effective diffusion coefficient, the fraction that is available for lixiviation and the tortuosity of the product. The physical meaning of the determined tortuosity is not clear. The behavior of tracers in the product is compared with the behavior of the corresponding element. Often this behavior deviates, sometimes even considerably. From a comparison of fly ash products it appears that cement bounded products are better able to combine with arsenicum and antimony than fired products. None of the investigated products caused concentrations of micro-elements way above the stated norm. Improvement as for lixiviation behavior of the products seems to be possible, in particular for bricks. 8 refs., 17 tabs., 26 figs.

  4. Have tsetse flies disappeared from Brazzaville town?

    Directory of Open Access Journals (Sweden)

    Patrick Bitsindou

    2009-08-01

    Full Text Available Background: From 1980 to 1985, the zoological park of Brazzaville was the only tsetse resting site located in downtown which supplied others temporary sites. The last trapping survey carried out in this area in 1987 showed that there were no more tsetse flies. Knowing that areas free of tsetse used to be reinvaded many years later, we have carried out an entomological survey in the area with the aim to verify what has happened more than twenty years later; given that suitable environmental conditions for Glossina are still available. Methods: Sixteen pyramidal traps were set out at the edge of the forest, along paths and around animal’s cages and were examined twice a day, at 10 a.m. and 4 p.m. during four days. Results: No tsetse fly was captured. Using the formula previously described; the probability of capturing a tsetse fly is 0.002. Conclusion: The zoological park seems close to be free of tsetse flies. Long-lasting surveys within the town and around are required before stating a complete disappearance of tsetse in the town.

  5. Formation flying; an interview with Tobias Gutleb

    NARCIS (Netherlands)

    Gutleb, T.; Perenboom, T.

    2011-01-01

    One of last year's Desig Synthesis Exercise (DSE) groups dived into the concept of fuel saving by letting aircraft flying in formation. They took their project even a step further and applied for the National Aviation Prize, a contest which encourages innovation in aerospace applications. The prize

  6. Refractive index of the fly rhabdomere

    NARCIS (Netherlands)

    Beersma, D.G.M.; Hoenders, B.J.; Huiser, A.M.J.; Toorn, P. van

    1982-01-01

    The refractive index and the diameter of the fly rhabdomere were determined by comparing the experimental results derived from interference microscopy with the results of a theoretical study on the scattering of plane waves by a homogeneous, isotropic cylindrical dielectric rod. It was found that

  7. Multicopter Design Challenge: Design, Fly, and Learn

    Science.gov (United States)

    Sutton, Kevin G.; Busby, Joe R.; Kelly, Daniel P.

    2016-01-01

    A great deal of the nation's attention has turned to the sky as new technologies open the door for new opportunities with unmanned aerial vehicles (UAVs). UAVs are powered aerial vehicles that do not carry an operator, use aerodynamic forces to provide vehicle lift, and can fly autonomously or be piloted remotely. As people become accustomed to…

  8. A Coincidental Sound Track for "Time Flies"

    Science.gov (United States)

    Cardany, Audrey Berger

    2014-01-01

    Sound tracks serve a valuable purpose in film and video by helping tell a story, create a mood, and signal coming events. Holst's "Mars" from "The Planets" yields a coincidental soundtrack to Eric Rohmann's Caldecott-winning book, "Time Flies." This pairing provides opportunities for upper elementary and…

  9. Decision-making capacity of flies

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Fruit flies (Drosophila melanogaster) can make appropriate choices among alternative flight options based on the relative salience of competing visual cues, according to a recent study by a team under the leadership of GUO Aike from the CAS Institute of Neuroscience.

  10. Formation flying; an interview with Tobias Gutleb

    NARCIS (Netherlands)

    Gutleb, T.; Perenboom, T.

    2011-01-01

    One of last year's Desig Synthesis Exercise (DSE) groups dived into the concept of fuel saving by letting aircraft flying in formation. They took their project even a step further and applied for the National Aviation Prize, a contest which encourages innovation in aerospace applications. The prize

  11. Volunteer Flying Organizations: Law Enforcements Untapped Resource

    Science.gov (United States)

    2016-12-01

    volunteers took on many of the following duties to help enable CAP functions: clerical work , aircraft maintenance , refueling operations, first aid...Highway Patrol, Monterey County Aero Squadron, Lane County Sheriff’s Office, Civil Air Patrol, volunteer flying organizations, law enforcement...5 3. Civil Air Patrol’s Use in Law Enforcement .................................7 D. POTENTIAL EXPLANATIONS AND HYPOTHESES

  12. FLY ASH: AN ALTERNATIVE TO POWDERED ACTIVATED ...

    African Journals Online (AJOL)

    Preferred Customer

    Also, fly ash has been found to be an efficient adsorbent for water treatment in the removal of ... properties for the removal of metal ions and organics; the residual sludge produced is used in ... investigate the reuse of the adsorbent for better economy of the process. ..... Ogbomoso, Oyo State, Nigeria to complete this article.

  13. The fruit flies (Tephritidae) of Ontario

    Science.gov (United States)

    Thirteen species of Tephritidae are newly recorded from Ontario, and alternative format keys are provided to the 31 genera and 72 species of fruit fly now known from, or likely to occur, in the province. Standard dichotomous keys to genera, and simplified field keys to genera and species are provide...

  14. Heavy metals in MSW incineration fly ashes

    DEFF Research Database (Denmark)

    Ferreira, Celia; Ribeiro, Alexandra B.; Ottosen, Lisbeth M.

    2003-01-01

    Incineration is a common solution for dealing with the increasing amount of municipal solid waste (MSW). During the process, the heavy metals initially present in the waste go through several transformations, ending up in combustion products, such as fly ash. This article deals with some issues r...

  15. Unidentified Flying Objects, A Selected Bibliography.

    Science.gov (United States)

    Rodgers, Kay, Comp.

    This bibliography, intended for the general reader, provides selective coverage of the unidentified flying object (UFO) literature that has appeared since 1969. The coverage is limited to English language works, but does include translations and materials published abroad. Other bibliographies are listed, as are books, congressional and other…

  16. Calcium homeostasis in fly photoreceptor cells

    NARCIS (Netherlands)

    Oberwinkler, J

    2002-01-01

    In fly photoreceptor cells, two processes dominate the Ca2+ homeostasis: light-induced Ca2+ influx through members of the TRP family of ion channels, and Ca2+ extrusion by Na+/Ca2+ exchange.Ca2+ release from intracellular stores is quantitatively insignificant. Both, the light-activated channels and

  17. "Lord of the Flies". [Lesson Plan].

    Science.gov (United States)

    Discovery Communications, Inc., Bethesda, MD.

    Based on William Golding's novel "Lord of the Flies," this lesson plan presents activities designed to help students understand that, on a literal level, the novel deals with what happens to a group of boys stranded on an island; and that on a symbolic level, it investigates what happens to civilized people when the structures of civilization…

  18. On Optical Crosstalk between Fly Rhabdomeres

    NARCIS (Netherlands)

    Wijngaard, W.; Stavenga, D.G.

    1975-01-01

    In a fly retinula light may be transferred among the rhabdomeres. It is estimated that the light from a point source imaged on the axis of a rhabdomere may eventually be transferred completely to a neighbouring rhabdomere. However, the effect on the sensitivity of this latter rhabdomere will remain

  19. Measurement on Camber Deformation of Wings of Free-flying Dragonflies and Beating-flying Dragonflies

    Institute of Scientific and Technical Information of China (English)

    Deqiang Song; Lijiang Zeng

    2004-01-01

    The knowledge of wing orientation and deformation during flapping flight is necessary for a complete aerodynamic analysis, but to date those kinematic features have not been simultaneously quantified for free-flying insects. A projected comb-fringe (PCF) method has been developed for measuring spanwise camber changes on free-flying dragonflies and on beating-flying dragonflies through the course of a wingbeat, which bases on projecting a fringe pattern over the whole measurement area and then measuring the wing deformation from the distorted fringe pattern. Experimental results demonstrate substantial camber changes both along the wingspan and through the course of a wingbeat. The ratio of camber deformation to chord length for hind wing is up to 0.11 at 75% spanwise with a flapping angle of -0.66 degree for a free-flying dragonfly.

  20. Advanced control technology and airworthiness flying qualities requirements

    Science.gov (United States)

    Snyder, C. T.

    1976-01-01

    Flying quality requirements are specified in terms of the complete pilot-airframe-systems loop, the task, and the environment. Results from a study of flying qualities are reported. A review of the treatment of failure cases in various flying quality requirements is presented along with a description of the methods used and relevant lessons learned from recent Autoland certification programs.

  1. Caribbean Fruit Fly (Diptera: Tephritidae) and Small Fruit in Florida

    Science.gov (United States)

    Tephritid fruit flies are among the most important pests of fruits and vegetables worldwide. The Caribbean fruit fly, Anastrepha suspensa (Loew), is a tephritid pest that became established in Florida following introduction in 1965. Populations of this fruit fly also occur in Puerto Rico and Cuba, ...

  2. Pandora bullata (Entomophthorales) affecting calliphorid flies in Central Brazil

    Science.gov (United States)

    Fungi are where one finds them, and if one seeks fungal pathogens affecting flies, then a garbage dump may be an ideal place to find both persistent, abundant fly populations and their fungal pathogens. An obvious fungal epizootic affecting blue bottle flies, Chrysomyia megacephala (Diptera: Calliph...

  3. Flies remember the time of day.

    Science.gov (United States)

    Chouhan, Nitin S; Wolf, Reinhard; Helfrich-Förster, Charlotte; Heisenberg, Martin

    2015-06-15

    The circadian clock enables organisms to anticipate daily environmental cycles and drives corresponding changes in behavior [1, 2]. Such endogenous oscillators also enable animals to display time-specific memory [1, 3-5]. For instance, mice and honeybees associate the location of a stimulus (like food or mate) with a certain time of day (time-place learning) [6, 7]. However, the mechanism underlying time-related learning and memory is not known. In the present study, we investigate time-specific odor learning. We use a genetically tractable animal, the fly Drosophila melanogaster. Starved flies are trained in the morning and afternoon to associate distinct odors with sucrose reward. The training is repeated the next day, and their time-dependent odor preference is tested on the third day. Our results indicate that Drosophila can express appetitive memory at the relevant time of day if the two conditioning events are separated by more than 4 hr. Flies can form time-odor associations in constant darkness (DD) as well as in a daily light-dark (LD) cycle, but not when kept under constant light (LL) conditions. Circadian clock mutants, period(01) (per(01)) and clock(AR) (clk(AR)), learned to associate sucrose reward with a certain odor but were unable to form time-odor associations. Our findings show that flies can utilize temporal information as an additional cue in appetitive learning. Time-odor learning in flies depends on a per- and clk-dependent endogenous mechanism that is independent of environmental light cues.

  4. Pollen recovered from the exoskeleton of stable flies, Stomoxys calcitrans (L.) in Gainesville, Florida

    Science.gov (United States)

    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...

  5. Puncture resistance in 'Sharwil' avocado to oriental fruit fly and Mediterranean fruit fly (Diptera: Tephritidae) oviposition.

    Science.gov (United States)

    Follett, Peter A

    2009-06-01

    The physiological basis for host antibiosis or nonpreference to a quarantine pest is often not understood. Studies are needed on the mechanisms that impart resistance to better understand how resistance might fail. Experiments were conducted to examine the infestability of 'Sharwil' avocados by oriental fruit fly, Bactrocera dorsalis (Hendel), and Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), after harvest and to quantify the effect of avocado skin hardness on resistance to infestation by oriental fruit fly. Infestation rate increased with decreasing fruit firmness, but fruit were generally poor hosts. Fruit with a patch of skin removed produced more flies than intact fruit, suggesting that skin puncture resistance was an important deterrent to oviposition. This study showed that fruit can be infested within 1 d after harvest, suggesting that fruit should be transferred to fruit fly-proof containers as they are harvested to minimize the risk of attack. Although risk of infestation is negatively correlated with fruit firmness, even some hard fruit may become infested. Therefore, fruit firmness cannot be used alone as an indicator to ensure fruit fly-free 'Sharwil' avocados. Measuring fruit firmness may be a useful component of a multiple component systems approach as an additional safeguard to reduce risk of infestation.

  6. Effect of four commercial fungal formulations on mortality and sporulation of house flies (Musca domestica) and stable flies (Stomoxys calcitrans)

    Science.gov (United States)

    House flies (Musca domestica L.) and stable flies (Stomoxys calcitrans (L.)) (Diptera: Muscidae) are major pests of livestock. Biological control is an important tool in an integrated control framework. Increased mortality in filth flies has been documented with entomopathogenic fungi, and several s...

  7. Future fly ash marketing; Flugaschevermarktung in der Zukunft

    Energy Technology Data Exchange (ETDEWEB)

    Mauder, R.; Hugot, A. [Evonik Power Minerals GmbH, Dinslaken (Germany)

    2008-07-01

    It can be assumed that the fly ash production volumes will undergo a marked increase over the next few years. The conditions of fly ash production will improve as a result of modern and refurbished power plants, yielding a positive effect on the quality of fly ashes. Other vital parameters of future fly ash marketing are fly ash logistics and the infrastructure of power plants. Basically, economic utilisation of the increased production volumes is possible; however, new and long-term strategies are necessary. (orig.)

  8. 岩松鼠的食物贮藏行为%Food-hoarding behaviour of David's rock squirrel Sciurotamias davidianus

    Institute of Scientific and Technical Information of China (English)

    路纪琪; 张知彬

    2005-01-01

    Food storage is an important adaptation of some animal species to the temporal variation or unpredictable food supplies. David's rock squirrel Sciurotamias davidianus occurs in mountainous and hilly areas of north China. Food-hoarding behaviour of this species was unknown. We set up four semi-natural enclosures in the Donglingshan Mountain area near Beijing, and investigate the hoarding strategy of 12 David's rock squirrels and their response to perceived pilferage on seeds of walnuts Juglans regia and wild apricot Prunus armeniaca. The results show that: 1) David's rock squirrels hoarded food items in both larder and scatter patterns but more items were scatter hoarded; 2) when confronted by perceived pilferage on hoarded food, David's rock squirrels increased both larder hoarding and scattered hoarding; 3) none of the seeds of wild apricot and walnut were eaten at the feeder. David's rock squirrels consumed more seeds of wild apricot than that of walnuts outside nest boxes; 4) David's rock squirrels only scatter hoarded walnuts; and 5) seeds of walnuts were transported greater distances than that of wild apricot. The result suggests that David's rock squirrels might play different roles in natural regeneration of walnuts and wild apricots[Acta Zoologica Sinica 51(3):376-382,2005].%食物贮藏是许多动物对不可预见的食物供应变化的一种重要适应.岩松鼠(Sciurotamias davidianus)为中国特有物种,广泛分布于华北地区的山地和丘陵地带.作者在北京市东灵山地区建造半自然围栏(4 m×3 m× 1 m),以核桃(Juglans regia)和山杏(Prunus armeniaca)种子为备选食物,对岩松鼠(12只)的食物贮藏行为进行了研究.数据的统计分析采用SPSS for Windows进行.研究结果表明:1)岩松鼠表现出集中和分散两种食物贮藏方式,而分散贮藏是其偏好的贮藏方式;2) 当遇到贮藏食物被盗窃时,岩松鼠倾向于搬运更多的食物进行集中和分散贮藏;3)岩松鼠没有在食

  9. A light and electron microscopic study of the inferior olivary nucleus of the squirrel monkey, Saimiri sciureus.

    Science.gov (United States)

    Rutherford, J G; Gwyn, D G

    1980-01-01

    This study provides a description of the normal morphology of the inferior olive of the squirrel monkey, Saimiri sciureus, at the light and electron imcroscopic level. The cytoarchitecture of the inferior olive was maped from serial transverse sections stained with cresyl violet. In common with other mammals, the inferior olive of the squirrel monkey consists of three subdivisions. The medial accessory olive includes seven subnuclei. Both the dorsal and medial accessory olives extend through approximately 90% of the total length of the inferior olivary complex. The principal olive, consisting of a dorsal and ventral lamella continuous with one another laterally, extends through the rostral 55% of the inferior olive. It is somewhat less convoluted than the principal olive of the macaque (Bowman and Sladek, '73). In most other respects, the inferior olive of the two primates is quite similar. Two patterns of dendritic arborization are noted in Golgi preparations from the caudal principal and accessory olives. Dendrites streaming away from the soma, and dendrites curling around the soma in a "ball-like" pattern were observed in all three subdivisions of the inferior olive caudally. Simple spines are occasionally seen on the soma, and a few simple or club-shaped spines were noted on the proximal portion of the dendritic arborization. Spines are more numerous on distal portions of the dendritic tree, however, and include simple, filiform, club-shaped and occasionally complex, or racemous, spiny appendages. Viewed in the electron microscope, most inferior olivary neurons are seen to contain the typical organelles with the usual conformation and distribution. Rarely, a neuron with an indented nucleus and a thin rim of cytoplasm containing a paucity of organelles and a wispy endoplasmic reticulum is encountered. Axon terminals containing either clear round or clear pleomorphic vesicles are seen in all three olivary subdivisions. In a random survey of 706 axon terminals, 54

  10. Analysis list: FLI1 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available FLI1 Blood,Bone,Muscle + hg19 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/FLI1.1.tsv http:...//dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/FLI1.5.tsv http://dbarchive.biosciencedb...c.jp/kyushu-u/hg19/target/FLI1.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/FLI1.Blood.tsv,http:...//dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/FLI1.Bone.tsv,http://dbarchive....biosciencedbc.jp/kyushu-u/hg19/colo/FLI1.Muscle.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/Blood.gml,http:

  11. Experimental study on fly ash capture mercury in flue gas

    Institute of Scientific and Technical Information of China (English)

    Mercedes; DíAZ-SOMOANO; Patricia; ABAD-VALLE; M.Rosa; MARTíNEZ-TARAZONA

    2010-01-01

    Systematic experiments were conducted on a fixed-bed reactor to investigate the interaction between fly ash and mercury,the results implied that fly ash can capture mercury effectively.Among different fly ashes,the unburned carbon in the FA2 and FA3 fly ashes has the highest mercury capture capacity,up to 10.3 and 9.36 μg/g,respectively,which is close to that of commercial activated carbon.There is no obvious relationship between mercury content and carbon content or BET surface area of fly ash.Petrography classification standard was applied to distinguish fly ash carbon particles.Carbon content is not the only variable that controls mercury capture on fly ash,there are likely significant differences in the mercury capture capacities of the various carbon forms.Mercury capture capacity mainly depends on the content of anisotropy carbon particles with porous network structure.

  12. Soluble components of the flagellar export apparatus, FliI, FliJ, and FliH, do not deliver flagellin, the major filament protein, from the cytosol to the export gate.

    Science.gov (United States)

    Sajó, Ráchel; Liliom, Károly; Muskotál, Adél; Klein, Agnes; Závodszky, Péter; Vonderviszt, Ferenc; Dobó, József

    2014-11-01

    Flagella, the locomotion organelles of bacteria, extend from the cytoplasm to the cell exterior. External flagellar proteins are synthesized in the cytoplasm and exported by the flagellar type III secretion system. Soluble components of the flagellar export apparatus, FliI, FliH, and FliJ, have been implicated to carry late export substrates in complex with their cognate chaperones from the cytoplasm to the export gate. The importance of the soluble components in the delivery of the three minor late substrates FlgK, FlgL (hook-filament junction) and FliD (filament-cap) has been convincingly demonstrated, but their role in the transport of the major filament component flagellin (FliC) is still unclear. We have used continuous ATPase activity measurements and quartz crystal microbalance (QCM) studies to characterize interactions between the soluble export components and flagellin or the FliC:FliS substrate-chaperone complex. As controls, interactions between soluble export component pairs were characterized providing Kd values. FliC or FliC:FliS did not influence the ATPase activity of FliI alone or in complex with FliH and/or FliJ suggesting lack of interaction in solution. Immobilized FliI, FliH, or FliJ did not interact with FliC or FliC:FliS detected by QCM. The lack of interaction in the fluid phase between FliC or FliC:FliS and the soluble export components, in particular with the ATPase FliI, suggests that cells use different mechanisms for the export of late minor substrates, and the major substrate, FliC. It seems that the abundantly produced flagellin does not require the assistance of the soluble export components to efficiently reach the export gate. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Production of ceramics from coal fly ash

    Directory of Open Access Journals (Sweden)

    Angjusheva Biljana

    2012-01-01

    Full Text Available Dense ceramics are produced from fly ash from REK Bitola, Republic of Macedonia. Four types of fly ash from electro filters and one from the collected zone with particles < 0.063 mm were the subject of this research. Consolidation was achieved by pressing (P= 133 MPa and sintering (950, 1000, 1050 and 11000C and heating rates of 3 and 100/min. Densification was realized by liquid phase sintering and solid state reaction where diopside [Ca(Mg,Al(Si,Al2O6] was formed. Ceramics with optimal properties (porosity 2.96±0.5%, bending strength - 47.01±2 MPa, compressive strength - 170 ±5 MPa was produced at 1100ºC using the heating rate of 10ºC/min.

  14. Focus characteristics of long distance flying optics

    Institute of Scientific and Technical Information of China (English)

    程兆谷; 蒋金波; 李现勤; 许国良; 夏金安; W.M.Steen; G.Dearden

    2000-01-01

    The ABCD law for the complex parameter q of the TEM00 Gaussian beam is generally not valid for high-order modes. It can be used for the high-order modes or their superposition when the spot size w in the virtual part of the parameter q is substituted by the Rayleigh range ZR of a certain resonator. The focus characteristics of long distance flying optics are studied in this paper theoretically and experimentally for the TEMmn Gaussian beams between the two types of resonators without and with distortion. It is very important for the applications of the flying optical processing, the laser space craft and the spatial filter in the large laser project.

  15. CFD Analysis of UAV Flying Wing

    Directory of Open Access Journals (Sweden)

    Vasile PRISACARIU

    2016-09-01

    Full Text Available Numerical methods for solving equations describing the evolution of 3D fluid experienced a significant development closely related to the progress of information systems. Today, especially in the field of fluid mechanics, numerical simulations allow the study of gas-thermodynamic confirmed by experimental techniques in wind tunnel conditions and actual flight tests for modeling complex aircraft. The article shows a case of numerical analysis of the lifting surface on the UAV type flying wing.

  16. Metalimnobia crane flies (Diptera: Limoniidae) from Korea.

    Science.gov (United States)

    Podenas, Sigitas; Byun, Hye-Woo

    2016-06-30

    Korean species of the crane fly genus Metalimnobia Matsumura, 1911 (Diptera: Limoniidae), are taxonomically revised. Metalimnobia (Metalimnobia) channpayna new species, is described and figured, M. (M.) bifasciata (Schrank, 1781), M. (M.) quadrinotata (Meigen, 1818) and M. (M.) zetterstedti (Tjeder, 1968) are listed for the first time in Korea, new information for previously known species, M. (M.) quadrimaculata (Linnaeus, 1760) is added. Identification key for all Korean Metalimnobia species is given. Wings, male and female terminalia are illustrated for all species.

  17. Evil in Lord of the Flies

    Institute of Scientific and Technical Information of China (English)

    黄靓

    2008-01-01

    Lord of the Flies deals with the problem of the nature of human personality and the reflection of personality on society.Devils hidesomewhere dee in side of all people.Without morals,law and order it will eventually surface and come out.Evil it;the natural product of their con-sciousness.Simon understands,and this is the wisdom Golding treats with awe.that evil is"only us".

  18. Burn Injury Arise From Flying Balloon Toys

    OpenAIRE

    Yalcin Kulahci; Fatih Zor; Mehmet Bozkurt; Serdar Ozturk; Mustafa Sengezer

    2007-01-01

    Many of peoples are faced minor or major burn injuries in their life. Even the most widespread burn cause is flame injuries, too different burn cause pointed out in literature like Acetylen burns. The cases which imply in literature, mostly causes from explosion of high pressure acetylene tube, metal oxygene patch flame or carbide lamp using from cave explorers. An interesting acetylene burn cause in Turkey was publised by the authors. This cases was to come into being from flying toy balloon...

  19. Vision in Flies: Measuring the Attention Span.

    Science.gov (United States)

    Koenig, Sebastian; Wolf, Reinhard; Heisenberg, Martin

    2016-01-01

    A visual stimulus at a particular location of the visual field may elicit a behavior while at the same time equally salient stimuli in other parts do not. This property of visual systems is known as selective visual attention (SVA). The animal is said to have a focus of attention (FoA) which it has shifted to a particular location. Visual attention normally involves an attention span at the location to which the FoA has been shifted. Here the attention span is measured in Drosophila. The fly is tethered and hence has its eyes fixed in space. It can shift its FoA internally. This shift is revealed using two simultaneous test stimuli with characteristic responses at their particular locations. In tethered flight a wild type fly keeps its FoA at a certain location for up to 4s. Flies with a mutation in the radish gene, that has been suggested to be involved in attention-like mechanisms, display a reduced attention span of only 1s.

  20. Vision in Flies: Measuring the Attention Span.

    Directory of Open Access Journals (Sweden)

    Sebastian Koenig

    Full Text Available A visual stimulus at a particular location of the visual field may elicit a behavior while at the same time equally salient stimuli in other parts do not. This property of visual systems is known as selective visual attention (SVA. The animal is said to have a focus of attention (FoA which it has shifted to a particular location. Visual attention normally involves an attention span at the location to which the FoA has been shifted. Here the attention span is measured in Drosophila. The fly is tethered and hence has its eyes fixed in space. It can shift its FoA internally. This shift is revealed using two simultaneous test stimuli with characteristic responses at their particular locations. In tethered flight a wild type fly keeps its FoA at a certain location for up to 4s. Flies with a mutation in the radish gene, that has been suggested to be involved in attention-like mechanisms, display a reduced attention span of only 1s.

  1. Spacecraft formation flying: Dynamics, control and navigation

    Science.gov (United States)

    Alfriend, Kyle Terry; Vadali, Srinivas Rao; Gurfil, Pini; How, Jonathan; Breger, Louis S.

    2009-12-01

    Space agencies are now realizing that much of what has previously been achieved using hugely complex and costly single platform projects - large unmanned and manned satellites (including the present International Space Station) - can be replaced by a number of smaller satellites networked together. The key challenge of this approach, namely ensuring the proper formation flying of multiple craft, is the topic of this second volume in Elsevier's Astrodynamics Series, Spacecraft Formation Flying: Dynamics, control and navigation. In this unique text, authors Alfriend et al. provide a coherent discussion of spacecraft relative motion, both in the unperturbed and perturbed settings, explain the main control approaches for regulating relative satellite dynamics, using both impulsive and continuous maneuvers, and present the main constituents required for relative navigation. The early chapters provide a foundation upon which later discussions are built, making this a complete, standalone offering. Intended for graduate students, professors and academic researchers in the fields of aerospace and mechanical engineering, mathematics, astronomy and astrophysics, Spacecraft Formation Flying is a technical yet accessible, forward-thinking guide to this critical area of astrodynamics.

  2. Examining the nature of fear of flying.

    Science.gov (United States)

    Hawkins-Gilligan, Janice; Dygdon, Judith A; Conger, Anthony J

    2011-10-01

    The nature of fear of flying (FOF) is not well understood. It is commonly assumed to be a fear learned from flight-specific experiences. However, existing literature suggests that FOF is a manifestation of fears of other stimuli (e.g., heights) embedded in the flying situation, but not specific to it. This study compared the level of prediction of FOF attained from flight-specific conditioning experiences (specifically, classical conditioning experiences in direct, observational, and verbal modes) with the level of prediction attained from flight-embedded fears. There were 109 university students who completed the Flight Anxiety Situations Questionnaire (FAS) and the Fear Survey Schedule, Version III (FSS) as well as demographic and flying experience questionnaires built for this study. All FOF measures were highly predicted by at least one flight-embedded fear. Conversely, conditioning experiences predicted only four of five FOF measures and this prediction was not strong. In general, conditioning experiences did not behave as in previous studies of conditioning and fear. The results suggest that FOF is based more on several flight-embedded innate fears than on learned fears. The implications of these results for FOF emergence and prevention are discussed.

  3. Accurate Segmentation for Infrared Flying Bird Tracking

    Institute of Scientific and Technical Information of China (English)

    ZHENG Hong; HUANG Ying; LING Haibin; ZOU Qi; YANG Hao

    2016-01-01

    Bird strikes present a huge risk for air ve-hicles, especially since traditional airport bird surveillance is mainly dependent on inefficient human observation. For improving the effectiveness and efficiency of bird monitor-ing, computer vision techniques have been proposed to detect birds, determine bird flying trajectories, and pre-dict aircraft takeoff delays. Flying bird with a huge de-formation causes a great challenge to current tracking al-gorithms. We propose a segmentation based approach to enable tracking can adapt to the varying shape of bird. The approach works by segmenting object at a region of inter-est, where is determined by the object localization method and heuristic edge information. The segmentation is per-formed by Markov random field, which is trained by fore-ground and background mixture Gaussian models. Exper-iments demonstrate that the proposed approach provides the ability to handle large deformations and outperforms the m ost state-of-the-art tracker in the infrared flying bird tracking problem.

  4. Flying the Needles: Flight Deck Automation Erodes Fine-Motor Flying Skills Among Airline Pilots.

    Science.gov (United States)

    Haslbeck, Andreas; Hoermann, Hans-Juergen

    2016-06-01

    The aim of this study was to evaluate the influence of practice and training on fine-motor flying skills during a manual instrument landing system (ILS) approach. There is an ongoing debate that manual flying skills of long-haul crews suffer from a lack of flight practice due to conducting only a few flights per month and the intensive use of automation. However, objective evidence is rare. One hundred twenty-six randomly selected airline pilots had to perform a manual flight scenario with a raw data precision approach. Pilots were assigned to four equal groups according to their level of practice and training by fleet (short-haul, long-haul) and rank (first officer, captain). Average ILS deviation scores differed significantly in relation to the group assignments. The strongest predictor variable was fleet, indicating degraded performance among long-haul pilots. Manual flying skills are subject to erosion due to a lack of practice on long-haul fleets: All results support the conclusion that recent flight practice is a significantly stronger predictor for fine-motor flying performance than the time period since flight school or even the total or type-specific flight experience. Long-haul crews have to be supported in a timely manner by adequate training tailored to address manual skills or by operational provisions like mixed-fleet flying or more frequent transitions between short-haul and long-haul operation. © 2016, Human Factors and Ergonomics Society.

  5. FlyCap: Markerless Motion Capture Using Multiple Autonomous Flying Cameras.

    Science.gov (United States)

    Xu, Lan; Liu, Yebin; Cheng, Wei; Guo, Kaiwen; Zhou, Guyue; Dai, Qionghai; Fang, Lu

    2017-07-18

    Aiming at automatic, convenient and non-instrusive motion capture, this paper presents a new generation markerless motion capture technique, the FlyCap system, to capture surface motions of moving characters using multiple autonomous flying cameras (autonomous unmanned aerial vehicles(UAVs) each integrated with an RGBD video camera). During data capture, three cooperative flying cameras automatically track and follow the moving target who performs large-scale motions in a wide space. We propose a novel non-rigid surface registration method to track and fuse the depth of the three flying cameras for surface motion tracking of the moving target, and simultaneously calculate the pose of each flying camera. We leverage the using of visual-odometry information provided by the UAV platform, and formulate the surface tracking problem in a non-linear objective function that can be linearized and effectively minimized through a Gaussian-Newton method. Quantitative and qualitative experimental results demonstrate the plausible surface and motion reconstruction results.

  6. Milk matters: offspring survival in Columbian ground squirrels is affected by nutrient composition of mother’s milk

    Directory of Open Access Journals (Sweden)

    Amy eSkibiel

    2015-10-01

    Full Text Available Through maternal effects, information about environmental conditions experienced in the maternal generation can be transmitted to subsequent generations. Although maternal effects have been described and quantified in many mammalian species, the underlying causal links are often under-studied. The close association between mother and neonate during the extended period of lactation in mammals provides a unique opportunity for mothers to influence offspring phenotype through nutrient provisioning of milk. The purpose of this study was to examine sources of inter-individual variation in milk composition and impacts on offspring phenotype and survival. Variation in fat content, protein content, and energy density of mother’s milk was associated with timing of reproduction. Mothers with intermediate birthdates produced milk that was higher in fat and energy density, but lower in protein than females with early or late birthdates. In turn, the pattern of change in milk composition affected juvenile overwinter survival. The protein content of Columbian ground squirrel milk typically increases to peak lactation and then declines before weaning. Pups consuming milk that was lower in protein in early lactation but then relatively high in protein at peak and late lactation had a higher probability of survival overwinter. Our results indicate that the interplay between the timing of reproduction and lactation performance has consequences for maternal and offspring fitness.

  7. Effects of prenatal /sup 60/Co irradiation on postnatal neural, learning, and hormonal development of the squirrel monkey

    Energy Technology Data Exchange (ETDEWEB)

    Ordy, J.M.; Brizzee, K.R.; Dunlap, W.P.; Knight, C.

    1982-02-01

    The goals of this study were to examine the effects of 0, 50, and 100 rad of /sup 60/Co administered prenatally on postnatal development of neuromuscular coordination, visual discrimination learning, spontaneous light-dark stabilimeter activity, plasma cortisol, and somatometric growth rates of diurnal squirrel monkeys from birth to 90 days. In terms of accuracy, completeness, and time required for performance of reflexes and neuromuscular coordination, the performance of 50- and 100-rad offspring was less accurate and poorly coordinated and required more time for completion to that of controls. In visual orientation, discrimination, and reversal learning, the percentage correct responses of the 50- and 100-rad offspring were significantly lower than those of controls. Spontaneous light-dark stabilimeter activity of 50- and 100-rad offspring was significantly higher in the dark session than that of controls. Plasma cortisol was significantly higher in 100-rad infants than in controls. Comparisons of somatometric growth rates indicated that postnatal head circumference, crown-rump length, and to a lesser extent body weight increased at significantly slower rates in 50- and 100-rad offspring. These findings should provide essential information for formulating and carrying out multivariate behavioral, biochemical, and morphometric assessments of low-dose effects on the brain of primate offspring within demonstrable dose-response curves.

  8. Purification and properties of glyceraldehyde-3-phosphate dehydrogenase from the skeletal muscle of the hibernating ground squirrel, Ictidomys tridecemlineatus

    Directory of Open Access Journals (Sweden)

    Ryan A.V. Bell

    2014-10-01

    Full Text Available Glyceraldehyde-3-phosphate dehydrogenase (GAPDH from the skeletal muscle of euthermic and torpid Ictidomys tridecemlineatus was purified to electrophoretic homogeneity using a novel method involving Blue-agarose and Phenyl-agarose chromatography. Kinetic analysis of the enzymes isolated from the two conditions suggested the existence of two structurally distinct proteins, with GAPDH V max being 40–60% less for the enzyme from the torpid condition (in both glycolytic and gluconeogenic directions as compared to the euthermic enzyme form. Thermal denaturation, in part determined by differential scanning fluorimetry, revealed that purified GAPDH from the torpid animals was significantly more stable that the enzyme from the euthermic condition. Mass spectrometry combined with Western blot analyses of purified GAPDH indicate that the cellular GAPDH population is extensively modified, with posttranslational phosphorylation, acetylation and methylation being detected. Global reduction in GAPDH tyrosine phosphorylation during torpor as well as site specific alterations in methylation sites suggests that that the stable changes observed in kinetic and structural GAPDH properties may be due to posttranslational modification of this enzyme during torpor. Taken together, these results suggest a stable suppression of GAPDH (possibly by some reversible posttranslational modification during ground squirrel torpor, which likely contributes to the overall reduction in carbohydrate metabolism when these animals switch to lipid fuels during dormancy.

  9. Biochemical adaptations of mammalian hibernation: exploring squirrels as a perspective model for naturally induced reversible insulin resistance

    Energy Technology Data Exchange (ETDEWEB)

    Wu, C-W.; Biggar, K.K.; Storey, K.B. [Carleton University, Department of Biology, Institute of Biochemistry, Ottawa, ON (Canada)

    2013-01-28

    An important disease among human metabolic disorders is type 2 diabetes mellitus. This disorder involves multiple physiological defects that result from high blood glucose content and eventually lead to the onset of insulin resistance. The combination of insulin resistance, increased glucose production, and decreased insulin secretion creates a diabetic metabolic environment that leads to a lifetime of management. Appropriate models are critical for the success of research. As such, a unique model providing insight into the mechanisms of reversible insulin resistance is mammalian hibernation. Hibernators, such as ground squirrels and bats, are excellent examples of animals exhibiting reversible insulin resistance, for which a rapid increase in body weight is required prior to entry into dormancy. Hibernator studies have shown differential regulation of specific molecular pathways involved in reversible resistance to insulin. The present review focuses on this growing area of research and the molecular mechanisms that regulate glucose homeostasis, and explores the roles of the Akt signaling pathway during hibernation. Here, we propose a link between hibernation, a well-documented response to periods of environmental stress, and reversible insulin resistance, potentially facilitated by key alterations in the Akt signaling network, PPAR-γ/PGC-1α regulation, and non-coding RNA expression. Coincidentally, many of the same pathways are frequently found to be dysregulated during insulin resistance in human type 2 diabetes. Hence, the molecular networks that may regulate reversible insulin resistance in hibernating mammals represent a novel approach by providing insight into medical treatment of insulin resistance in humans.

  10. Sexual selection in the squirrel treefrog Hyla squirella: the role of multimodal cue assessment in female choice

    Science.gov (United States)

    Taylor, Ryan C.; Buchanan, Bryant W.; Doherty, Jessie L.

    2007-01-01

    Anuran amphibians have provided an excellent system for the study of animal communication and sexual selection. Studies of female mate choice in anurans, however, have focused almost exclusively on the role of auditory signals. In this study, we examined the effect of both auditory and visual cues on female choice in the squirrel treefrog. Our experiments used a two-choice protocol in which we varied male vocalization properties, visual cues, or both, to assess female preferences for the different cues. Females discriminated against high-frequency calls and expressed a strong preference for calls that contained more energy per unit time (faster call rate). Females expressed a preference for the visual stimulus of a model of a calling male when call properties at the two speakers were held the same. They also showed a significant attraction to a model possessing a relatively large lateral body stripe. These data indicate that visual cues do play a role in mate attraction in this nocturnal frog species. Furthermore, this study adds to a growing body of evidence that suggests that multimodal signals play an important role in sexual selection.

  11. A review on the utilization of fly ash

    Energy Technology Data Exchange (ETDEWEB)

    M. Ahmaruzzaman [National Institute of Technology Silchar, Silchar (India). Department of Chemistry

    2010-06-15

    Fly ash, generated during the combustion of coal for energy production, is an industrial by-product which is recognized as an environmental pollutant. Because of the environmental problems presented by the fly ash, considerable research has been undertaken on the subject worldwide. In this paper, the utilization of fly ash in construction, as a low-cost adsorbent for the removal of organic compounds, flue gas and metals, light weight aggregate, mine back fill, road sub-base, and zeolite synthesis is discussed. A considerable amount of research has been conducted using fly ash for adsorption of NOx, SOx, organic compounds, and mercury in air, dyes and other organic compounds in waters. It is found that fly ash is a promising adsorbent for the removal of various pollutants. The adsorption capacity of fly ash may be increased after chemical and physical activation. It was also found that fly ash has good potential for use in the construction industry. The conversion of fly ash into zeolites has many applications such as ion exchange, molecular sieves, and adsorbents. Converting fly ash into zeolites not only alleviates the disposal problem but also converts a waste material into a marketable commodity. Investigations also revealed that the unburned carbon component in fly ash plays an important role in its adsorption capacity. Future research in these areas is also discussed. 428 refs., 3 figs., 7 tabs.

  12. A review on the utilization of fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Ahmaruzzaman, M. [Department of Chemistry, National Institute of Technology Silchar, Silchar-788010, Assam (India)

    2010-06-15

    Fly ash, generated during the combustion of coal for energy production, is an industrial by-product which is recognized as an environmental pollutant. Because of the environmental problems presented by the fly ash, considerable research has been undertaken on the subject worldwide. In this paper, the utilization of fly ash in construction, as a low-cost adsorbent for the removal of organic compounds, flue gas and metals, light weight aggregate, mine back fill, road sub-base, and zeolite synthesis is discussed. A considerable amount of research has been conducted using fly ash for adsorption of NO{sub x}, SO{sub x}, organic compounds, and mercury in air, dyes and other organic compounds in waters. It is found that fly ash is a promising adsorbent for the removal of various pollutants. The adsorption capacity of fly ash may be increased after chemical and physical activation. It was also found that fly ash has good potential for use in the construction industry. The conversion of fly ash into zeolites has many applications such as ion exchange, molecular sieves, and adsorbents. Converting fly ash into zeolites not only alleviates the disposal problem but also converts a waste material into a marketable commodity. Investigations also revealed that the unburned carbon component in fly ash plays an important role in its adsorption capacity. Future research in these areas is also discussed. (author)

  13. House Fly (Musca domestica L.) Attraction to Insect Honeydew.

    Science.gov (United States)

    Hung, Kim Y; Michailides, Themis J; Millar, Jocelyn G; Wayadande, Astri; Gerry, Alec C

    2015-01-01

    House flies are of major concern as vectors of food-borne pathogens to food crops. House flies are common pests on cattle feedlots and dairies, where they develop in and feed on animal waste. By contacting animal waste, house flies can acquire human pathogenic bacteria such as Escherichia coli and Salmonella spp., in addition to other bacteria, viruses, or parasites that may infect humans and animals. The subsequent dispersal of house flies from animal facilities to nearby agricultural fields containing food crops may lead to pre-harvest food contamination with these pathogens. We hypothesized that odors from honeydew, the sugary excreta produced by sucking insects feeding on crops, or molds and fungi growing on honeydew, may attract house flies, thereby increasing the risk of food crop contamination. House fly attraction to honeydew-contaminated plant material was evaluated using a laboratory bioassay. House flies were attracted to the following plant-pest-honeydew combinations: citrus mealybug on squash fruit, pea aphid on faba bean plants, whitefly on navel orange and grapefruit leaves, and combined citrus mealybug and cottony cushion scale on mandarin orange leaves. House flies were not attracted to field-collected samples of lerp psyllids on eucalyptus plants or aphids on crepe myrtle leaves. Fungi associated with field-collected honeydews were isolated and identified for further study as possible emitters of volatiles attractive to house flies. Two fungal species, Aureobasidium pullulans and Cladosporium cladosporioides, were repeatedly isolated from field-collected honeydew samples. Both fungal species were grown in potato dextrose enrichment broth and house fly attraction to volatiles from these fungal cultures was evaluated. House flies were attracted to odors from A. pullulans cultures but not to those of C. cladosporioides. Identification of specific honeydew odors that are attractive to house flies could be valuable for the development of improved house

  14. House Fly (Musca domestica L. Attraction to Insect Honeydew.

    Directory of Open Access Journals (Sweden)

    Kim Y Hung

    Full Text Available House flies are of major concern as vectors of food-borne pathogens to food crops. House flies are common pests on cattle feedlots and dairies, where they develop in and feed on animal waste. By contacting animal waste, house flies can acquire human pathogenic bacteria such as Escherichia coli and Salmonella spp., in addition to other bacteria, viruses, or parasites that may infect humans and animals. The subsequent dispersal of house flies from animal facilities to nearby agricultural fields containing food crops may lead to pre-harvest food contamination with these pathogens. We hypothesized that odors from honeydew, the sugary excreta produced by sucking insects feeding on crops, or molds and fungi growing on honeydew, may attract house flies, thereby increasing the risk of food crop contamination. House fly attraction to honeydew-contaminated plant material was evaluated using a laboratory bioassay. House flies were attracted to the following plant-pest-honeydew combinations: citrus mealybug on squash fruit, pea aphid on faba bean plants, whitefly on navel orange and grapefruit leaves, and combined citrus mealybug and cottony cushion scale on mandarin orange leaves. House flies were not attracted to field-collected samples of lerp psyllids on eucalyptus plants or aphids on crepe myrtle leaves. Fungi associated with field-collected honeydews were isolated and identified for further study as possible emitters of volatiles attractive to house flies. Two fungal species, Aureobasidium pullulans and Cladosporium cladosporioides, were repeatedly isolated from field-collected honeydew samples. Both fungal species were grown in potato dextrose enrichment broth and house fly attraction to volatiles from these fungal cultures was evaluated. House flies were attracted to odors from A. pullulans cultures but not to those of C. cladosporioides. Identification of specific honeydew odors that are attractive to house flies could be valuable for the

  15. 围栏条件下岩松鼠对核桃的贮藏%Hoarding of walnuts by David's rock squirrels (Sciurotamias davidianus)within enclosure

    Institute of Scientific and Technical Information of China (English)

    路纪琪; 张知彬

    2007-01-01

    许多动物都能够贮藏食物以应对一定时期的食物短缺.岩松鼠是中国特有的一种啮齿动物,主要分布于华北山地和丘陵地区,对于其食物贮藏行为还了解不多.我们在北京东灵山地区建立了半自然围栏,在围栏一角设置一木质巢箱供其休息,在围栏中心设一食盘(给食处),就岩松鼠对核桃(已预先标记)的贮藏特征进行了观察.每只受试动物在实验开始前6 h断食,于13∶00左右,随机选择1只岩松鼠,将其放入围栏中适应2~3 h.随后,在给食处放置20枚已标记的核桃.于第二天同一时间进入围栏,检查并记录岩松鼠对核桃的处理情况,将埋藏、取食和剩余的核桃全部移出,另置20枚新的核桃,继续实验.第三天,重复上述检查和记录,将岩松鼠及被其处理的核桃全部移出,清理巢箱、整理围栏.随后放入第二只岩松鼠,重复上述实验过程,如遇恶劣气候,则实验顺延,直至实验结束.结果表明:岩松鼠兼具集中贮藏和分散贮藏两种食物贮藏方式,并且分散方式是其主要的食物贮藏方式;岩松鼠在围栏中选择一定的位置贮藏食物;文中还讨论了可能影响岩松鼠食物贮藏的因素.%A variety of animals store food to cope with temporally variable or unpredictable food supplies.We have little knowledge of the food hoarding behavior of David's rock squirrels (Sciurotamias davidianus), a species endemic to China and mainly distributed in the hilly temperate zone in northern China.We constructed semi-natural enclosures in the Donglingshan mountains area in which we investigated the squirrels' food hoarding behavior by providing them with tagged walnuts (Juglans regia).The results showed that David's rock squirrels exhibited both larder and scatter hoarding, and the latter seemed to be their preferred choice.Artificial pilferage of hoarded food items had no significant effect on the hoarding behavior of squirrels.Within the enclosures

  16. Use of insecticide-impregnated ear tags for the control of face flies and horn-flies on pastured cattle.

    Science.gov (United States)

    Williams, R E; Westby, E J; Hendrix, K S; Lemenager, R P

    1981-11-01

    Three studies were conducted to evaluate the effectiveness of insecticide-impregnated ear tags in controlling face flies, Musca autumnalis DeGeer, and horn flies, Haematobia irritans (Linn.), on pastured beef cattle. In one 16-week trial, polyvinyl chloride (PVC) ear tags treated with stirofos (Rabon) insecticide reduced horn fly numbers by 79% (P less than .05) and face fly numbers by 30% (P less than .05). Coumaphos (Co-Ral) insecticide dust bags used in a separate herd produced an 86% (P less than .05) reduction in horn flies and an 18% (P less than .05) reduction in face flies. In the second study, 5 and 10% permethrin (Atroban), PVC-treated ear tags in a one-piece design were tested. In this 11 week trial, horn fly control averaged 95% (P less than .05) with the 10% tag and 77% (P less than .05) with the 5% tag. Face fly control averaged 49% (P less than .05) for 8 weeks with the 10% permethrin tag. No significant face fly control was achieved with the 5% permethrin tag. In a herd treated with coumaphos dust bags, horn fly control averaged 93% (P less than .05) and face fly control averaged 34% (P less than .05). The third study tested 5 and 10% permethrin, PVC-treated ear tags in a two-piece design and two-piece 5% permethrin-treated ear tags in a polyurethane matrix. Fourteen-week horn fly control averaged 88% (P less than .05) with the 10% PVC-treated tag, 83% (P less than .05) with the 5% PVC-treated tag, 71% (P less than .05) with the 5% polyurethane-treated tag and 74% (P less than .05) with coumaphos dust bags. Face fly control averaged less than 50% (P greater than .05) throughout the trial with all treatments.

  17. FliH and FliI ensure efficient energy coupling of flagellar type III protein export in Salmonella.

    Science.gov (United States)

    Minamino, Tohru; Kinoshita, Miki; Inoue, Yumi; Morimoto, Yusuke V; Ihara, Kunio; Koya, Satomi; Hara, Noritaka; Nishioka, Noriko; Kojima, Seiji; Homma, Michio; Namba, Keiichi

    2016-06-01

    For construction of the bacterial flagellum, flagellar proteins are exported via its specific export apparatus from the cytoplasm to the distal end of the growing flagellar structure. The flagellar export apparatus consists of a transmembrane (TM) export gate complex and a cytoplasmic ATPase complex consisting of FliH, FliI, and FliJ. FlhA is a TM export gate protein and plays important roles in energy coupling of protein translocation. However, the energy coupling mechanism remains unknown. Here, we performed a cross-complementation assay to measure robustness of the energy transduction system of the export apparatus against genetic perturbations. Vibrio FlhA restored motility of a Salmonella ΔflhA mutant but not that of a ΔfliH-fliI flhB(P28T) ΔflhA mutant. The flgM mutations significantly increased flagellar gene expression levels, allowing Vibrio FlhA to exert its export activity in the ΔfliH-fliI flhB(P28T) ΔflhA mutant. Pull-down assays revealed that the binding affinities of Vibrio FlhA for FliJ and the FlgN-FlgK chaperone-substrate complex were much lower than those of Salmonella FlhA. These suggest that Vibrio FlhA requires the support of FliH and FliI to efficiently and properly interact with FliJ and the FlgN-FlgK complex. We propose that FliH and FliI ensure robust and efficient energy coupling of protein export during flagellar assembly.

  18. Environmental impact of using fly ash in concrete

    Energy Technology Data Exchange (ETDEWEB)

    1978-09-01

    An attempt was made to estimate the chemical composition of fly ash using the known chemical composition of coals from numerous regions of the country and the known behavior of elements in a limited number of coal and fly-ash samples. This technique assumes that each element in every piece of coal in the United States partitions itself into fly ash to the same extent and leaches from fly ash at the same rate. Using these limited data, enrichment factors were then calculated by dividing the composition in the fly ash by the composition in the corresponding coal samples. These enrichment factors were then applied to all of the coal samples for which chemical compositions were available to estimate the chemical composition of the fly ash.

  19. Analysis list: Fli1 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Fli1 Blood,Embryo + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Fli1....1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Fli1.5.tsv http://dbarchive.biosciencedbc.jp/kyu...shu-u/mm9/target/Fli1.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Fli1.Blood.tsv,http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Fli1.Embryo.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Blood.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Embryo.gml ...

  20. Fly ash of mineral coal as ceramic tiles raw material.

    Science.gov (United States)

    Zimmer, A; Bergmann, C P

    2007-01-01

    The aim of this work was to evaluate the use of mineral coal fly ash as a raw material in the production of ceramic tiles. The samples of fly ash came from Capivari de Baixo, a city situated in the Brazilian Federal State of Santa Catarina. The fly ash and the raw materials were characterized regarding their physical chemical properties, and, based on these results; batches containing fly ash and typical raw materials for ceramic tiles were prepared. The fly ash content in the batches varied between 20 and 80 wt%. Specimens were molded using a uniaxial hydraulic press and were fired. All batches containing ash up to 60 wt% present adequate properties to be classified as several kinds of products in the ISO 13006 standard () regarding its different absorption groups (pressed). The results obtained indicate that fly ash, when mixed with traditional raw materials, has the necessary requirements to be used as a raw material for production of ceramic tiles.

  1. A 3D high resolution ex vivo white matter atlas of the common squirrel monkey (saimiri sciureus) based on diffusion tensor imaging

    Science.gov (United States)

    Gao, Yurui; Parvathaneni, Prasanna; Schilling, Kurt G.; Wang, Feng; Stepniewska, Iwona; Xu, Zhoubing; Choe, Ann S.; Ding, Zhaohua; Gore, John C.; Chen, Li min; Landman, Bennett A.; Anderson, Adam W.

    2016-03-01

    Modern magnetic resonance imaging (MRI) brain atlases are high quality 3-D volumes with specific structures labeled in the volume. Atlases are essential in providing a common space for interpretation of results across studies, for anatomical education, and providing quantitative image-based navigation. Extensive work has been devoted to atlas construction for humans, macaque, and several non-primate species (e.g., rat). One notable gap in the literature is the common squirrel monkey - for which the primary published atlases date from the 1960's. The common squirrel monkey has been used extensively as surrogate for humans in biomedical studies, given its anatomical neuro-system similarities and practical considerations. This work describes the continued development of a multi-modal MRI atlas for the common squirrel monkey, for which a structural imaging space and gray matter parcels have been previously constructed. This study adds white matter tracts to the atlas. The new atlas includes 49 white matter (WM) tracts, defined using diffusion tensor imaging (DTI) in three animals and combines these data to define the anatomical locations of these tracks in a standardized coordinate system compatible with previous development. An anatomist reviewed the resulting tracts and the inter-animal reproducibility (i.e., the Dice index of each WM parcel across animals in common space) was assessed. The Dice indices range from 0.05 to 0.80 due to differences of local registration quality and the variation of WM tract position across individuals. However, the combined WM labels from the 3 animals represent the general locations of WM parcels, adding basic connectivity information to the atlas.

  2. Assessment of the stress response in Columbian ground squirrels: laboratory and field validation of an enzyme immunoassay for fecal cortisol metabolites.

    Science.gov (United States)

    Bosson, Curtis O; Palme, Rupert; Boonstra, Rudy

    2009-01-01

    Stress responses play a critical role in the ecology and demography of wild animals, and the analysis of fecal hormone metabolites is a powerful noninvasive method to assess the role of stress. We characterized the metabolites of injected radiolabeled cortisol in the urine and feces of Columbian ground squirrels and validated an enzyme immunoassay for measuring fecal cortisol metabolites (FCM) with a 5 alpha-3beta,11 beta-diol structure by stimulation and suppression of adrenocortical activity and by evaluation of the circadian pattern of FCM excretion. In addition, we also evaluated the impact of capture, handling, and acclimation to the laboratory on FCM. Cortisol is highly metabolized, with virtually none being excreted, and of the radiolabeled cortisol injected, 31% was recovered in urine and 6.5% in feces. The lag time between cortisol injection and its appearance in urine and feces was 4.5 +/- 0.82 (SE) h and 7.0 +/- 0.53 (SE) h, respectively. FCM levels varied over the day, reflecting circadian variation in endogenous cortisol. Dexamethasone decreased FCM levels by 33%, and ACTH increased them by 255%. Trapping and housing initially increased FCM levels and decreased body mass, but these reversed within 3-7 d, indicating acclimation. Finally, FCM levels were modestly repeatable over time (r=0.57) in wild, live trapped, nonbreeding animals, indicating that FCMs provide a measure of the squirrel's stress-axis state. This assay provides a robust noninvasive assessment of the stress response of the Columbian ground squirrel and will facilitate an integration of its life history and physiology.

  3. A 3D high resolution ex vivo white matter atlas of the common squirrel monkey (Saimiri sciureus) based on diffusion tensor imaging.

    Science.gov (United States)

    Gao, Yurui; Parvathaneni, Prasanna; Schilling, Kurt G; Wang, Feng; Stepniewska, Iwona; Xu, Zhoubing; Choe, Ann S; Ding, Zhaohua; Gore, John C; Chen, Li Min; Landman, Bennett A; Anderson, Adam W

    2016-02-27

    Modern magnetic resonance imaging (MRI) brain atlases are high quality 3-D volumes with specific structures labeled in the volume. Atlases are essential in providing a common space for interpretation of results across studies, for anatomical education, and providing quantitative image-based navigation. Extensive work has been devoted to atlas construction for humans, macaque, and several non-primate species (e.g., rat). One notable gap in the literature is the common squirrel monkey - for which the primary published atlases date from the 1960's. The common squirrel monkey has been used extensively as surrogate for humans in biomedical studies, given its anatomical neuro-system similarities and practical considerations. This work describes the continued development of a multi-modal MRI atlas for the common squirrel monkey, for which a structural imaging space and gray matter parcels have been previously constructed. This study adds white matter tracts to the atlas. The new atlas includes 49 white matter (WM) tracts, defined using diffusion tensor imaging (DTI) in three animals and combines these data to define the anatomical locations of these tracks in a standardized coordinate system compatible with previous development. An anatomist reviewed the resulting tracts and the inter-animal reproducibility (i.e., the Dice index of each WM parcel across animals in common space) was assessed. The Dice indices range from 0.05 to 0.80 due to differences of local registration quality and the variation of WM tract position across individuals. However, the combined WM labels from the 3 animals represent the general locations of WM parcels, adding basic connectivity information to the atlas.

  4. Functional differentiation of trailing and leading forelimbs during locomotion on the ground and on a horizontal branch in the European red squirrel (Sciurus vulgaris, Rodentia).

    Science.gov (United States)

    Schmidt, André

    2011-06-01

    Mammalian locomotion is characterized by the frequent use of in-phase gaits in which the footfalls of the left and right fore- or hindlimbs are unevenly spaced in time. Although previous studies have identified a functional differentiation between the first limb (trailing limb) and the second limb (leading limb) to touch the ground during terrestrial locomotion, the influence of a horizontal branch on limb function has never been explored. To determine the functional differences between trailing and leading forelimbs during locomotion on the ground and on a horizontal branch, X-ray motion analysis and force measurements were carried out in two European red squirrels (Sciurus vulgaris, Rodentia). The differences observed between trailing and leading forelimbs were minimal during terrestrial locomotion, where both limbs fulfill two functions and go through a shock-absorbing phase followed by a generating phase. During locomotion on a horizontal branch, European red squirrels reduce speed and all substrate reaction forces transmitted may be due to the reduction of vertical oscillation of the center of mass. Further adjustments during locomotion on a horizontal branch differ significantly between trailing and leading forelimbs and include limb flexion, lead intervals, limb protraction and vertical displacement of the scapular pivot. Consequently, trailing and leading forelimbs perform different functions. Trailing forelimbs function primarily as shock-absorbing elements, whereas leading forelimbs are characterized by a high level of stiffness. This functional differentiation indicates that European red squirrels 'test' the substrate for stability with the trailing forelimb, while the leading forelimb responds to or counteracts swinging or snapping branches. Copyright © 2011 Elsevier GmbH. All rights reserved.

  5. Fiber type distribution in the shoulder muscles of the tree shrew, the cotton-top tamarin, and the squirrel monkey related to shoulder movements and forelimb loading.

    Science.gov (United States)

    Schmidt, Manuela; Schilling, Nadja

    2007-04-01

    Muscle fiber type composition of intrinsic shoulder muscles was examined in tree shrews, cotton-top tamarins, and squirrel monkeys with respect to their shoulder kinematics and forelimb loading during locomotion. Enzyme- and immunohistochemical techniques were applied to differentiate muscle fiber types on serial cross-sections of the shoulder. In the majority of the shoulder muscles, the proportions of fatigue resistant slow-twitch fibers (SO) and fatigable fast-twitch fibers (FG) were inversely related to each other, whereas the percentage of intermediate FOG-fibers varied independently. A segregation of fatigue resistant SO-fibers into deep muscle regions is indicative of differential activation of histochemically distinct muscle regions in which deep regions stabilize the joint against gravitational loading. In all three species, this antigravity function was demonstrated for both the supraspinatus and the cranial subscapularis muscle, which prevent passive joint flexion during the support phase of the limb. The infraspinatus muscle showed a high content of SO-fibers in the primate species but not in the tree shrew, which demonstrates the "new" role of the infraspinatus muscle in joint stabilization related to the higher degree of humeral protraction in primates. In the tree shrew and the cotton-top tamarin, a greater proportion of the body weight is carried on the forelimb, but the squirrel monkey exhibits a weight shift to the hind limbs. The lower amount of forelimb loading is reflected by an overall lower proportion of fatigue resistant muscle fibers in the shoulder muscles of the squirrel monkey. Several muscles such as the deltoid no longer function as joint stabilizers and allow the humerus to move beyond the scapular plane. These differences among species demonstrate the high plasticity of the internal muscle architecture and physiology which is suggested to be the underlying reason for different muscle activity patterns in homologous muscles

  6. Eradicating the grey squirrel Sciurus carolinensis from urban areas: an innovative decision-making approach based on lessons learnt in Italy.

    Science.gov (United States)

    La Morgia, Valentina; Paoloni, Daniele; Genovesi, Piero

    2017-02-01

    Eradication of invasive alien species supports the recovery of native biodiversity. A new European Union Regulation introduces obligations to eradicate the most harmful invasive species. However, eradications of charismatic mammals may encounter strong opposition. Considering the case study of the eastern grey squirrel (Sciurus carolinensis Gmelin, 1788) in central Italy, we developed a structured decision-making technique based on a Bayesian decision network model and explicitly considering the plurality of environmental values of invasive species management to reduce potential social conflicts. The model identified priority areas for management activities. These areas corresponded to the core of the grey squirrel range, but they also included peripheral zones, where rapid eradication is fundamental to prevent the spread of squirrels. However, when the model was expanded to integrate the attitude of citizens towards the project, the intervention strategy slightly changed. In some areas, the citizens' support was limited, and this resulted in a reduced overall utility of intervention. The suggested approach extends the scientific basis for management decisions, evaluated in terms of technical efficiency, feasibility and social impact. Here, the Bayesian decision network model analysed the potential technical and social consequences of management actions, and it responded to the need for transparency in the decision-making process, but it can easily be extended to consider further issues that are common in many mammal eradication programmes. Owing to its flexibility and comprehensiveness, it provides an innovative example of how to plan rapid eradication or control activities, as required by the new EU Regulation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  7. Control of bloodsucking black fly (Simuliidae) populations in Lithuania

    OpenAIRE

    Bartninkaitė, Ilona; Bernotienė, Rasa; Pakalniškis, Saulius; Žygutienė, Milda

    2006-01-01

    The outbreak of bloodsucking black flies began in the 70s of the 20th century in the south-eastern part of Lithuania. By 1990, the biting activity of bloodsucking black flies increased and had become a serious problem. The bloodsucking insects caused losses of cattle and domestic birds and tormented holiday-makers in the Druskininkai health-resort. Biological larvicide based on Bacillus thuringiensis var. israelensis was used for bloodsucking black fly control in 1999–2005. The larvicide was ...

  8. A soil emergence trap for collections of phlebotomine sand flies

    Directory of Open Access Journals (Sweden)

    Casanova Cláudio

    2001-01-01

    Full Text Available The identification of breeding sites of sand flies is of great epidemiological interest. A soil emergence trap for investigating potential sand fly breeding sites is described. The trap was tested in two rural areas in the Mogi Guaçu River Valley where the American cutaneous leishmaniasis is an endemic disease. Seventy-three sand fly individuals of three species, Lutzomyia intermedia s. l., L. whitmani and L. pessoai, were collected on the forest floor and peridomicile.

  9. 主提升鼠笼式异步电动机变频改造%Frequency Transformation of Main Hoisting Squirrel-cage Asynchronous Motors

    Institute of Scientific and Technical Information of China (English)

    申昭

    2011-01-01

    主提升鼠笼式异步电动机变频调速系统的改造,其中以产生SPWM的HEF4752为控制核心,实现了鼠笼式异步电动机变频调速的闭环控制。%The transformation of the frequency controlling system of main hoisting squirrel-cage asynchronous motors realizes the closed-loop frequency control with the HEF4752 that produces SPWM as the core.

  10. Starting Phenomena and Temperature-rise under vvvf Supply of Three-Phase Squirrel-Cage ac Traction Motor of Electric Locomotive

    Science.gov (United States)

    Paul, R. N.; Arya, L. D.; Verma, H. K.

    2012-09-01

    In three-phase squirrel-cage ac traction motor, temperature-rise calculation during variable-voltage and variable-frequency starting is of vital importance and has to be predicted and critically examined. Under voltage source inverter supply with PWM, the generation of harmonics by inverter supply reduces the output during starting due to higher harmonic losses, thereby reducing the starting tractive effort in kN on locomotive wheel. Stator and rotor temperature-rises during starting have been determined for average acceleration torque in segmental zone (calculated from variable acceleration) which have been presented in the paper with both copper and aluminium alloy rotor bars.

  11. A Novel Scheme for Reduction of Torque Ripple in Direct Torque Control of Three Phase Squirrel Cage Induction Motor Using Seven Level Neutral Point Clamped Inverter

    Directory of Open Access Journals (Sweden)

    S. Priya

    2013-02-01

    Full Text Available Direct torque control of a 3 phase squirrel cage Induction motor though offers a good dynamic response and is free from dynamic coordinate transformation has a major disadvantage of producing rippled torque which degrades the performance of entire drive system. A scheme is proposed in this study which employs seven levels Neutral point clamped inverter which helps in alleviating the torque disturbances. The control scheme for the proposed method is described in this study and the simulation results are reported to demonstrate its effectiveness.

  12. Multiple interstitial ribosomal sites (NORs in the Brazilian squirrel Sciurus aestuans ingrami (Rodentia, Sciuridae with 2n = 40: an overview of Sciurus cytogenetics

    Directory of Open Access Journals (Sweden)

    Valéria Fagundes

    2003-01-01

    Full Text Available This is the first time the karyotype of the Brazilian squirrel Sciurusaestuans ingrami, with 2n = 40, is described. The karyotype of this species comprises 18 pairs of biarmed and one minute pair of acrocentric autosomes, a medium-sized submetacentric X and a medium-sized acrocentric Y. Four pairs have an interstitial secondary constriction, co-located with nucleolar organizer regions (NORs, identified by silver-staining technique and fluorescent in situ hybridization (FISH with ribosomal 18S/28S probes. The occurrence of multiple interstitial NORs is rare in rodents, and this is one of the few examples, identified by a molecular cytogenetics approach.

  13. A thermal and electrical dynamic mathematical model for squirrel cage induction motors; Modelamento matematico dinamico termico e eletrico de motores de inducao

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Ronaldo Martins de

    1996-01-01

    A thermal and electrical dynamic mathematical model for squirrel cage induction motors is presented. The electrical model is described by Park equation and the torque equation, while the thermal model is described by a system of four first order differential equations that represent the motor heat transfer process. The model presented can be used to determine thermal and electrical performance for any operation condition. However, it is suitable mainly for machines operating under continuously transient condition. The presented mathematical model also incorporate variation of rotor winding electrical parameters due to skin effect. (author)

  14. Adaptive Supervisory Engine for Autonomous Formation Flying GNC Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Autonomous multiple spacecraft formation flying represents a critical enabling technology for future space missions, including NASA's Space and Earth Science...

  15. Surface Modification of Fly Ash for Active Catalysis

    Directory of Open Access Journals (Sweden)

    Deepti Jain

    2013-01-01

    Full Text Available Fly ash based effective solid base catalyst (KF/Al2O3/fly ash473, KF/Al2O3/fly ash673, and KF/Al2O3/fly ash873 was synthesized by loading KF over chemically and thermally activated fly ash. The chemical activation was done by treating fly ash with aluminum nitrate via precipitation method followed by thermal activation at 650°C to increase the alumina content in fly ash. The increased alumina content was confirmed by SEM-EDX analysis. The alumina enriched fly ash was then loaded with KF (10 wt% and calcined at three different temperatures 473 K, 673 K and 873 K. The amount of loaded KF was monitored by XRD, FTIR spectroscopy, SEM-EDX, TEM and Flame Atomic Absorption Spectrophotometer. The catalytic activities of the catalysts were tested in the Claisen-Schmidt condensation of benzaldehyde and 4-methoxybenzaldehyde with 2′-hydroxyacetophenone to produce 2′-hydroxychalcone and 4-methoxy-2′-hydroxychalcone respectively. Higher conversion (83% of benzaldehyde and (89% of 4-methoxybenzaldehyde reveals that among these heterogeneous catalysts KF/Al2O3/fly ash673 is very active.

  16. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    DEFF Research Database (Denmark)

    Lima, A.T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2012-01-01

    the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even......Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through...

  17. Experimental Study on Volume for Fly Ash of Building Block

    Directory of Open Access Journals (Sweden)

    Ling Wang

    2013-04-01

    Full Text Available Fly ash is a waste substance from thermal power plants, steel mills, etc. That is found in abundance in the world. It has polluted the environment, wasting the cultivated land. This study introduces an experimental research on fly ash being reused effectively, the study introduces raw materials of fly ash brick, production process and product inspection, fly ash content could be amounted to 40%~75%. High doping fly ash bricks are manufactured, which selects wet fly ash from the power plants, adding aggregate with reasonable ratio and additives with reasonable dosage and do the experimental research on manufacture products for properties, production technology and selection about technology parameter of production equipment. Index of strength grade and freezing-thawing resisting etc and the high doping fly ash brick building which we are working on can achieve the national standard on building materials industry. Based on the tests, this achievement of research has a very wide practical prospect in using fly ash, industrial waste residue, environmental protection and reducing the cost of enterprises. The efficient reuse of fly ash from coal boiler and power plants has very vital significance of protecting the environment, benefiting descendants and developing of circular economy.

  18. The Cement Solidification of Municipal Solid Waste Incineration Fly Ash

    Institute of Scientific and Technical Information of China (English)

    HOU Haobo; HE Xinghua; ZHU Shujing; ZHANG Dajie

    2006-01-01

    The chemical composition, the content and the leachability of heavy metals in municipal solid waste incineration ( MSWI) fly ash were tested and analyzed. It is shown that the leachability of Pb and Cr exceeds the leaching toxicity standard, and so the MSWI fly ash is considered as hazardous waste and must be solidifled. The effect of solidifying the MSWI fly ash by cement was studied, and it is indicated that the heavy metals can be well immobilized if the mass fraction of the fly ash is appropriate. The heavy metals were immobilized within cement hydration products through either physical fixation, substitution, deposition or adsorption mechanisms.

  19. Creep Behaviour of Fly Ash-Based Geopolymer Concrete

    OpenAIRE

    2010-01-01

    Fly ash-based geopolymer concrete is manufactured using fly ash as its source material and does not use Portland cement at all. Beside fly ash, alkaline solution is also utilized to make geopolymer paste which binds the aggregates to form geopolymer concrete. This paper presents the study of creep behaviour of fly ash-based geopolymer concrete. Four series of specimens with various compressive strengths were prepared to study its creep behaviour for the duration of test up to one year. The te...

  20. Electrodialytic removal of Cd from biomass combustion fly ash suspensions

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor M.; Ottosen, Lisbeth M.; Damoe, Anne J.

    2013-01-01

    Due to relatively high concentrations of Cd, biomass combustion fly ashes often fail to meet Danish legislative requirements for recycling as fertilizer. In this study, the potential of using electrodialytic remediation for removal of Cd from four different biomass combustion fly ashes was invest......Due to relatively high concentrations of Cd, biomass combustion fly ashes often fail to meet Danish legislative requirements for recycling as fertilizer. In this study, the potential of using electrodialytic remediation for removal of Cd from four different biomass combustion fly ashes...