Sample records for saltator linnaeus osteichthyes

  1. Giant saltation on Mars

    PubMed Central

    Almeida, Murilo P.; Parteli, Eric J. R.; Andrade, José S.; Herrmann, Hans J.

    2008-01-01

    Saltation, the motion of sand grains in a sequence of ballistic trajectories close to the ground, is a major factor for surface erosion, dune formation, and triggering of dust storms on Mars. Although this mode of sand transport has been matter of research for decades through both simulations and wind tunnel experiments under Earth and Mars conditions, it has not been possible to provide accurate measurements of particle trajectories in fully developed turbulent flow. Here we calculate the motion of saltating grains by directly solving the turbulent wind field and its interaction with the particles. Our calculations show that the minimal wind velocity required to sustain saltation on Mars may be surprisingly lower than the aerodynamic minimal threshold measurable in wind tunnels. Indeed, Mars grains saltate in 100 times higher and longer trajectories and reach 5-10 times higher velocities than Earth grains do. On the basis of our results, we arrive at general expressions that can be applied to calculate the length and height of saltation trajectories and the flux of grains in saltation under various physical conditions, when the wind velocity is close to the minimal threshold for saltation. PMID:18443302

  2. Wind-invariant saltation heights imply linear scaling of aeolian saltation flux with shear stress.

    PubMed

    Martin, Raleigh L; Kok, Jasper F

    2017-06-01

    Wind-driven sand transport generates atmospheric dust, forms dunes, and sculpts landscapes. However, it remains unclear how the flux of particles in aeolian saltation-the wind-driven transport of sand in hopping trajectories-scales with wind speed, largely because models do not agree on how particle speeds and trajectories change with wind shear velocity. We present comprehensive measurements, from three new field sites and three published studies, showing that characteristic saltation layer heights remain approximately constant with shear velocity, in agreement with recent wind tunnel studies. These results support the assumption of constant particle speeds in recent models predicting linear scaling of saltation flux with shear stress. In contrast, our results refute widely used older models that assume that particle speed increases with shear velocity, thereby predicting nonlinear 3/2 stress-flux scaling. This conclusion is further supported by direct field measurements of saltation flux versus shear stress. Our results thus argue for adoption of linear saltation flux laws and constant saltation trajectories for modeling saltation-driven aeolian processes on Earth, Mars, and other planetary surfaces.

  3. Wind-invariant saltation heights imply linear scaling of aeolian saltation flux with shear stress

    PubMed Central

    Martin, Raleigh L.; Kok, Jasper F.

    2017-01-01

    Wind-driven sand transport generates atmospheric dust, forms dunes, and sculpts landscapes. However, it remains unclear how the flux of particles in aeolian saltation—the wind-driven transport of sand in hopping trajectories—scales with wind speed, largely because models do not agree on how particle speeds and trajectories change with wind shear velocity. We present comprehensive measurements, from three new field sites and three published studies, showing that characteristic saltation layer heights remain approximately constant with shear velocity, in agreement with recent wind tunnel studies. These results support the assumption of constant particle speeds in recent models predicting linear scaling of saltation flux with shear stress. In contrast, our results refute widely used older models that assume that particle speed increases with shear velocity, thereby predicting nonlinear 3/2 stress-flux scaling. This conclusion is further supported by direct field measurements of saltation flux versus shear stress. Our results thus argue for adoption of linear saltation flux laws and constant saltation trajectories for modeling saltation-driven aeolian processes on Earth, Mars, and other planetary surfaces. PMID:28630907

  4. Measuring high spatiotemporal variability in saltation intensity using a low-cost Saltation Detection System: Wind tunnel and field experiments

    NASA Astrophysics Data System (ADS)

    de Winter, W.; van Dam, D. B.; Delbecque, N.; Verdoodt, A.; Ruessink, B. G.; Sterk, G.

    2018-04-01

    The commonly observed over prediction of aeolian saltation transport on sandy beaches is, at least in part, caused by saltation intermittency. To study small-scale saltation processes, high frequency saltation sensors are required on a high spatial resolution. Therefore, we developed a low-cost Saltation Detection System (SalDecS) with the aim to measure saltation intensity at a frequency of 10 Hz and with a spatial resolution of 0.10 m in wind-normal direction. Linearity and equal sensitivity of the saltation sensors were investigated during wind tunnel and field experiments. Wind tunnel experiments with a set of 7 SalDec sensors revealed that the variability of sensor sensitivity is at maximum 9% during relatively low saltation intensities. During more intense saltation the variability of sensor sensitivity decreases. A sigmoidal fit describes the relation between mass flux and sensor output measured during 5 different wind conditions. This indicates an increasing importance of sensor saturation with increasing mass flux. We developed a theoretical model to simulate and describe the effect of grain size, grain velocity and saltation intensity on sensor saturation. Time-averaged field measurements revealed sensitivity equality for 85 out of a set of 89 horizontally deployed SalDec sensors. On these larger timescales (hours) saltation variability imposed by morphological features, such as sand strips, can be recognized. We conclude that the SalDecS can be used to measure small-scale spatiotemporal variabilities of saltation intensity to investigate saltation characteristics related to wind turbulence.

  5. EXPRESSING SUPPLY LIMITATION IN SAND SALTATION

    EPA Science Inventory

    Saltation-driven sandblasting is the most effective producer of windblown dust. Modeling of wind-blown dust emissions requires an efficient parameterization of sand flux in the saltating mode. According to the theory of P. R. Owen the horizontal mass flux of saltating uniform p...

  6. Saltation of Non-Spherical Sand Particles

    PubMed Central

    Wang, Zhengshi; Ren, Shan; Huang, Ning

    2014-01-01

    Saltation is an important geological process and the primary source of atmospheric mineral dust aerosols. Unfortunately, no studies to date have been able to precisely reproduce the saltation process because of the simplified theoretical models used. For example, sand particles in most of the existing wind sand movement models are considered to be spherical, the effects of the sand shape on the structure of the wind sand flow are rarely studied, and the effect of mid-air collision is usually neglected. In fact, sand grains are rarely round in natural environments. In this paper, we first analyzed the drag coefficients, drag forces, and starting friction wind speeds of sand grains with different shapes in the saltation process, then established a sand saltation model that considers the coupling effect between wind and the sand grains, the effect of the mid-air collision of sand grains, and the effect of the sand grain shape. Based on this model, the saltation process and sand transport rate of non-spherical sand particles were simulated. The results show that the sand shape has a significant impact on the saltation process; for the same wind speed, the sand transport rates varied for different shapes of sand grains by as much as several-fold. Therefore, sand shape is one of the important factors affecting wind-sand movement. PMID:25170614

  7. Exploring Auditory Saltation Using the "Reduced-Rabbit" Paradigm

    ERIC Educational Resources Information Center

    Getzmann, Stephan

    2009-01-01

    Sensory saltation is a spatiotemporal illusion in which the judged positions of stimuli are shifted toward subsequent stimuli that follow closely in time. So far, studies on saltation in the auditory domain have usually employed subjective rating techniques, making it difficult to exactly quantify the extent of saltation. In this study, temporal…

  8. Aeolian saltation on Mars at low wind speeds

    NASA Astrophysics Data System (ADS)

    Sullivan, R.; Kok, J. F.

    2017-10-01

    Laboratory experiments indicate that the fluid threshold friction speed, u*tf, required to initiate fully developed aeolian saltation is much higher on Mars than on Earth. A discrepancy exists between Mars climate models that do not predict winds this strong and observations that sand-sized particles are indeed moving. This paper describes how wind friction speeds well below u*tf, but above the impact threshold, u*ti, required to sustain saltation, can initiate sustained saltation on Mars, but at relatively low flux. Numerical experiments indicate that a sand grain on Mars mobilized sporadically between u*ti and u*tf will develop, over fetch lengths longer than generally available within low-pressure wind tunnels, trajectories capable of splashing grains that propagate saltation and collectively form a cluster of saltating grains that migrate downwind together. The passage of a saltation cluster should leave behind a narrow zone of affected surface grains. The cumulative effect of many clusters represents a low-flux phenomenon that should produce slow changes to aeolian bedforms over periods in which winds remain close to u*ti and never or rarely reach u*tf. Field evidence from small impact ripples along rover traverses is consistent with effects of saltation at these low friction speeds, without obvious evidence for events ≥u*tf. The potential utility of this grain mobility process is that it can operate entirely at more common winds well below u*tf and so help explain widespread sand movements observed on Mars wherever evidence might be mostly absent for u*tf being exceeded.

  9. Estimation of saltation emission in the Kubuqi Desert, North China.

    PubMed

    Du, Heqiang; Xue, Xian; Wang, Tao

    2014-05-01

    The Kubuqi Desert suffered more severe wind erosion hazard. Every year, a mass of aeolian sand was blown in the Ten Tributaries that are tributaries of the Yellow River. To estimate the quantity of aeolian sediment blown into the Ten Tributaries from the Kubuqi Desert, it is necessary to simulate the saltation processes of the Kubuqi Desert. A saltation submodel of the IWEMS (Integrated Wind-Erosion Modeling System) and its accompanying RS (Remote Sensing) and GIS (Geographic Information System) methods were used to model saltation emissions in the Kubuqi Desert. To calibrate the saltation submodel, frontal area of vegetation, soil moisture, wind velocity and saltation sediment were observed synchronously on several points in 2011 and 2012. In this study, a model namely BEACH (Bridge Event And Continuous Hydrological) was introduced to simulate the daily soil moisture. Using the surface parameters (frontal area of vegetation and soil moisture) along with the observed wind velocities and saltation sediments for the observed points, the saltation model was calibrated and validated. To reduce the simulate error, a subdaily wind velocity program, WINDGEN was introduced in this model to simulate the hourly wind velocity of the Kubuqi Desert. By incorporating simulated hourly wind velocity, and model variables, the saltation emission of the Kubuqi Desert was modeled. The model results show that the total sediment flow rate was 1-30.99 tons/m over the last 10years (2001-2010). The saltation emission mainly occurs in the north central part of the Kubuqi Desert in winter and spring. Integrating the wind directions, the quantity of the aeolian sediment that deposits in the Ten Tributaries was estimated. Compared with the observed data by the local government and hydrometric stations, our estimation is reasonable. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. High-frequency measurements of aeolian saltation flux: Field-based methodology and applications

    NASA Astrophysics Data System (ADS)

    Martin, Raleigh L.; Kok, Jasper F.; Hugenholtz, Chris H.; Barchyn, Thomas E.; Chamecki, Marcelo; Ellis, Jean T.

    2018-02-01

    Aeolian transport of sand and dust is driven by turbulent winds that fluctuate over a broad range of temporal and spatial scales. However, commonly used aeolian transport models do not explicitly account for such fluctuations, likely contributing to substantial discrepancies between models and measurements. Underlying this problem is the absence of accurate sand flux measurements at the short time scales at which wind speed fluctuates. Here, we draw on extensive field measurements of aeolian saltation to develop a methodology for generating high-frequency (up to 25 Hz) time series of total (vertically-integrated) saltation flux, namely by calibrating high-frequency (HF) particle counts to low-frequency (LF) flux measurements. The methodology follows four steps: (1) fit exponential curves to vertical profiles of saltation flux from LF saltation traps, (2) determine empirical calibration factors through comparison of LF exponential fits to HF number counts over concurrent time intervals, (3) apply these calibration factors to subsamples of the saltation count time series to obtain HF height-specific saltation fluxes, and (4) aggregate the calibrated HF height-specific saltation fluxes into estimates of total saltation fluxes. When coupled to high-frequency measurements of wind velocity, this methodology offers new opportunities for understanding how aeolian saltation dynamics respond to variability in driving winds over time scales from tens of milliseconds to days.

  11. Surprises from the field: Novel aspects of aeolian saltation observed under natural turbulence

    NASA Astrophysics Data System (ADS)

    Martin, R. L.; Kok, J. F.; Chamecki, M.

    2015-12-01

    The mass flux of aeolian (wind-blown) sediment transport - critical for understanding earth and planetary geomorphology, dust generation, and soil stability - is difficult to predict. Recent work suggests that competing models for saltation (the characteristic hopping of aeolian sediment) fail because they do not adequately account for wind turbulence. To address this issue, we performed field deployments measuring high-frequency co-variations of aeolian saltation and near-surface winds at multiple sites under a range of conditions. Our observations yield several novel findings not currently captured by saltation models: (1) Saltation flux displays no significant lag relative to horizontal wind velocity; (2) Characteristic height of the saltation layer remains constant with changes in shear velocity; and (3) During saltation, the vertical profile of mean horizontal wind velocity is steeper than expected from the Reynolds stress. We examine how the interactions between saltation and turbulence in field settings could explain some of these surprising observations.

  12. Pathological and molecular characterization of systemic isosporosis (atoxoplasmosis) in captive green-winged saltator (Saltator similis).

    PubMed

    Oliveira, Ayisa Rodrigues de; Souza, Tayse Domingues de; Mol, Juliana P S; Flecher, Mayra Cunha; Hiura, Emy; Santos, Renato Lima

    2018-05-15

    Systemic isosporosis, also called atoxoplasmosis or visceral coccidiosis, is a disease that affects birds in general. Pathogenesis of systemic isosporosis and its etiologic agent have not been well characterized, but taxonomically Atoxoplasma is currently considered a junior objective synonym of Isospora. The present report aimed to describe pathological and molecular findings of systemic isosporosis in captive green-winged saltators (Saltator similis) from the State of Espírito Santo, Brazil. In a commercial breeding facility eleven birds with two to nine months of age died from 2015 to 2016. These birds developed nonspecific clinical signs, including bristly feathers, hyporexia, loss of weight, and apathy. Two birds were necropsied, and grossly there were hepatomegaly, splenomegaly, necrosis of lymphoid follicles, hepatic necrosis, and severe enteritis. Merozoites were observed in the heart, small intestine, proventriculus, brain, liver, spleen, and kidneys. 23 S RNA PCR amplicons from DNA extracted from the liver and the intestinal contents had 99% identity with Atoxoplasma sp., whereas amplicons of mitochondrial cytochrome c oxidase subunit 1 ha d 97% identity with Isospora greineri. In conclusion, this report indicates that systemic isosporosis in green-winged saltator is a disease that affects the spleen, liver, and small intestine, with high mortality for young birds, resulting in significant loses to commercial breeding facilities. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Trajectories of saltating sand particles behind a porous fence

    NASA Astrophysics Data System (ADS)

    Zhang, Ning; Lee, Sang Joon; Chen, Ting-Guo

    2015-01-01

    Trajectories of aeolian sand particles behind a porous wind fence embedded in a simulated atmospheric boundary layer were visualized experimentally, to investigate the shelter effect of the fence on sand saltation. Two sand samples, one collected from a beach (d = 250 μm) and the other from a desert (d = 100 μm), were tested in comparison with the previous studies of a 'no-fence' case. A wind fence (ε = 38.5%) was installed on a flat sand bed filled with each sand sample. A high-speed photography technique and the particle tracking velocimetry (PTV) method were employed to reconstruct the trajectories of particles saltating behind the fence. The collision processes of these sand particles were analyzed, momentum and kinetic energy transfer between saltating particles and ground surface were also investigated. In the wake region, probability density distributions of the impact velocities agree well with the pattern of no-fence case, and can be explained by a log-normal law. The horizontal component of impact velocity for the beach sand is decreased by about 54%, and about 76% for the desert sand. Vertical restitution coefficients of bouncing particles are smaller than 1.0 due to the presence of the wind fence. The saltating particles lose a large proportion of their energy during the collision process. These results illustrate that the porous wind fence effectively abates the further evolution of saltating sand particles.

  14. Explicit Two-Phase Modeling of the Initiation of Saltation over Heterogeneous Sand Beds

    NASA Astrophysics Data System (ADS)

    Turney, F. A.; Kok, J. F.; Martin, R. L.; Burr, D. M.; Bridges, N.; Ortiz, C. P.; Smith, J. K.; Emery, J. P.; Van Lew, J. T.

    2016-12-01

    The initiation of aeolian sediment transport is key in understanding the geomorphology of arid landscapes and emission of mineral dust into the atmosphere. Despite its importance, the process of saltation initiation remains poorly understood, and current models are highly simplified. Previous models of the initiation of aeolian saltation have assumed the particle bed to be monodisperse and homogeneous in arrangement, ignoring the distribution of particle thresholds created by different bed geometries and particle sizes. In addition, mean wind speeds are often used in place of a turbulent wind field, ignoring the distribution of wind velocities at the particle level. Furthermore, the transition from static bed to steady state saltation is often modeled as resulting directly from fluid lifting, while in reality particles need to hop and roll along the surface before attaining enough height and momentum to initiate the cascade of particle splashes that characterizes saltation. We simulate the initiation of saltation with a coupled two-phase CFD-DEM model that overcomes the shortcomings of previous models by explicitly modeling particle-particle and particle-fluid interactions at the particle scale. We constrain our model against particle trajectories taken from high speed video of initiation at the Titan Wind Tunnel at NASA Ames. Results give us insight into the probability that saltation will be initiated, given stochastic variations in bed properties and wind velocity.

  15. Wind driven saltation: a hitherto overlooked challenge for life on Mars

    NASA Astrophysics Data System (ADS)

    Bak, Ebbe; Goul, Michael; Rasmussen, Martin; Moeller, Ralf; Nørnberg, Per; Knak Jensen, Svend; Finster, Kai

    2017-04-01

    The Martian surface is a hostile environment characterized by low water availability, low atmospheric pressure and high UV and ionizing radiation. Furthermore, wind-driven saltation leads to abrasion of silicates with a production of reactive surface sites and, through triboelectric charging, a release of electrical discharges with a concomitant production of reactive oxygen species. While the effects of low water availability, low pressure and radiation have been extensively studied in relation to the habitability of the Martian surface and the preservation of organic biosignatures, the effects of wind-driven saltation have hitherto been ignored. In this study, we have investigated the effect of exposing bacteria to wind-abraded silicates and directly to wind-driven saltation on Mars in controlled laboratory simulation experiments. Wind-driven saltation was simulated by tumbling mineral samples in a Mars-like atmosphere in sealed quartz ampoules. The effects on bacterial survival and structure were evaluated by colony forming unit counts in combination with scanning electron microscopy, quantitative polymerase chain reaction and life/dead-staining with flow cytometry. The viability of vegetative cells of P. putida, B. subtilis and D. radiodurans in aqueous suspensions was reduced by more than 99% by exposure to abraded basalt, while the viability of B. subtilis endospores was unaffected. B. subtilis mutants lacking different spore components were likewise highly resistant to the exposure to abraded basalt, which indicates that the resistance of spores is not associated with any specific spore component. We found a significant but reduced effect of abraded quartz and we suggest that the stress effect of abraded silicates is induced by a production of reactive oxygen species and hydroxyl radicals produced by Fenton-like reactions in the presence of transition metals. Direct exposure to simulated saltation had a dramatic effect on both D. radiodurans cells and B

  16. Higher-than-predicted saltation threshold wind speeds on Titan.

    PubMed

    Burr, Devon M; Bridges, Nathan T; Marshall, John R; Smith, James K; White, Bruce R; Emery, Joshua P

    2015-01-01

    Titan, the largest satellite of Saturn, exhibits extensive aeolian, that is, wind-formed, dunes, features previously identified exclusively on Earth, Mars and Venus. Wind tunnel data collected under ambient and planetary-analogue conditions inform our models of aeolian processes on the terrestrial planets. However, the accuracy of these widely used formulations in predicting the threshold wind speeds required to move sand by saltation, or by short bounces, has not been tested under conditions relevant for non-terrestrial planets. Here we derive saltation threshold wind speeds under the thick-atmosphere, low-gravity and low-sediment-density conditions on Titan, using a high-pressure wind tunnel refurbished to simulate the appropriate kinematic viscosity for the near-surface atmosphere of Titan. The experimentally derived saltation threshold wind speeds are higher than those predicted by models based on terrestrial-analogue experiments, indicating the limitations of these models for such extreme conditions. The models can be reconciled with the experimental results by inclusion of the extremely low ratio of particle density to fluid density on Titan. Whereas the density ratio term enables accurate modelling of aeolian entrainment in thick atmospheres, such as those inferred for some extrasolar planets, our results also indicate that for environments with high density ratios, such as in jets on icy satellites or in tenuous atmospheres or exospheres, the correction for low-density-ratio conditions is not required.

  17. Spatiotemporal Integration in Somatosensory Perception: Effects of Sensory Saltation on Pointing at Perceived Positions on the Body Surface

    PubMed Central

    Trojan, Jörg; Stolle, Annette M.; Carl, Antonija Mršić; Kleinböhl, Dieter; Tan, Hong Z.; Hölzl, Rupert

    2010-01-01

    In the past, sensory saltation phenomena (Geldard and Sherrick, 1972) have been used repeatedly to analyze the spatiotemporal integration capacity of somatosensory and other sensory mechanisms by means of their psychophysical characteristic. The core phenomenon consists in a systematic mislocalization of one tactile stimulus (the attractee) toward another successive tactile stimulus (the attractant) presented at another location, increasing with shorter intervals. In a series of four experiments, sensory saltation characteristics were studied at the forearm and the abdomen. Participants reported the perceived positions of attractees, attractants, and reference stimuli by pointing. In general, saltation characteristics compared well to those reported in previous studies, but we were able to gain several new insights regarding this phenomenon: (a) the attractee–attractant interval did not exclusively affect the perceived attractee position, but also the perceived attractant position; (b) saltation characteristics were very similar at different body sites and orientations, but did show differences suggesting anisotropy (direction-dependency) in the underlying integration processes; (c) sensory saltation could be elicited with stimulation patterns crossing the body midline on the abdomen. In addition to the saltation-specific results, our experiments demonstrate that pointing reports of perceived positions on the body surface generally show pronounced systematic biases compared to veridical positions, moderate intraindividual consistency, and a high degree of inter-individual variability. Finally, we address methodological and terminological controversies concerning the sensory saltation paradigm and discuss its possible neurophysiological basis. PMID:21833262

  18. Validation of SWEEP for creep, saltation, and suspension in a desert-oasis ecotone

    NASA Astrophysics Data System (ADS)

    Pi, H.; Sharratt, B.; Feng, G.; Lei, J.; Li, X.; Zheng, Z.

    2016-03-01

    Wind erosion in the desert-oasis ecotone can accelerate desertification, but little is known about the susceptibility of the ecotone to wind erosion in the Tarim Basin despite being a major source of windblown dust in China. The objective of this study was to test the performance of the Single-event Wind Erosion Evaluation Program (SWEEP) in simulating soil loss as creep, saltation, and suspension in a desert-oasis ecotone. Creep, saltation, and suspension were measured and simulated in a desert-oasis ecotone of the Tarim Basin during discrete periods of high winds in spring 2012 and 2013. The model appeared to adequately simulate total soil loss (ranged from 23 to 2272 g m-2 across sample periods) according to the high index of agreement (d = 0.76). The adequate agreement of the SWEEP in simulating total soil loss was due to the good performance of the model (d = 0.71) in simulating creep plus saltation. The SWEEP model, however, inadequately simulated suspension based upon a low d (⩽0.43). The slope estimates of the regression between simulated and measured suspension and difference of mean suggested that the SWEEP underestimated suspension. The adequate simulation of creep plus saltation thus provides reasonable estimates of total soil loss using SWEEP in a desert-oasis environment.

  19. Diet and gut microbiota of two supralittoral amphipods Orchestia montagui and Talitrus saltator living in different microhabitats

    NASA Astrophysics Data System (ADS)

    Abdelrhman, Khaled F. A.; Bacci, Giovanni; Nistri, Annamaria; Mengoni, Alessio; Ugolini, Alberto

    2017-10-01

    Talitrus saltator (Montagu) and Orchestia montagui Audouin live in different microhabitats of the same supralittoral belt. T. saltator can be found in the damp sand of beaches with scarce or absent wracked material near the water line. O. montagui is frequently found in the Posidonia banquettes or under wracked material, often in contact with the substrate. This study investigates the effect of diet on species-specific gut microbiota patterns in these talitrid species. Adults were collected and fed with artificial food (commercial fish food and pieces of blotting paper) for 51 days. Gut microbiota were analyzed at five time intervals (0 h, 24 h, 7, 23 and 51 days) by 16S rRNA gene metagenomic analysis and by estimating the relative abundance of cellulases (glycosyl hydrolase gene family 48, GHF48) gene copies. The gut microbiota of O. montagui was more affected than that of T. saltator by diet shift. Although the taxonomic profile of the gut microbiota varied with time in both species, with an increase of Protobacteria in O. montagui and of Actinobacteria and Bacteroidetes in T. saltator, genes involved in cellulose degradation (GHF48 family) showed a large-scale increase in O. montagui but not in T. saltator. We conclude that the diet variation has different influence on the composition of gut microbiota in the two talitrid species in accordance with their different alimentary habits: the more generalist T. saltator (detritivore, grazer, and scavenger) showed less changes in its gut microbiota composition than the more specialist O. montagui (detritivore and grazer), which strongly modified its gut microbiota composition by the captivity diet.

  20. Saltation thresholds and entrainment of fine particles at Earth and Martian pressures

    NASA Technical Reports Server (NTRS)

    Leach, Rodman; Greeley, Ronald; Pollack, James

    1989-01-01

    An open circuit wind tunnel designed to operate in a large vacuum chamber was built at NASA-Ames to investigate saltation threshold, flux, deflation rates, and other aeolian phenomena on the planet Mars. The vacuum chamber will operate at pressures as low as 4 mbar, and the tunnel operates at windspeeds as high as 150 m/sec. Either air or CO2 can be used as a working fluid. It was found that, to a first order approximation, the same dynamic pressure was required at Martian pressure to entrain or saltate particles as was required on Earth, although wind and particle speed are considerably higher at Martian pressure. A 2nd wind tunnel, designed to operate aboard the NASA KC-135 0-g aircraft to obtain information on the effect of gravity on saltation threshold and the interparticle force at 0-g, is also described and test data presented. Some of the experiments are summarized and various aspects of low pressure aeolian entrainment for particles 12 to 100 micron in diameter are discussed, some of them unique to low pressure testing and some common in Earth pressure particle transport testing. The facility, the modes of operation, and the materials used are described.

  1. Evidence of repeated and independent saltational evolution in a peculiar genus of sphinx moths (Proserpinus: Sphingidae).

    PubMed

    Rubinoff, Daniel; Le Roux, Johannes J

    2008-01-01

    Saltational evolution in which a particular lineage undergoes relatively rapid, significant, and unparalleled change as compared with its closest relatives is rarely invoked as an alternative model to the dominant paradigm of gradualistic evolution. Identifying saltational events is an important first-step in assessing the importance of this discontinuous model in generating evolutionary novelty. We offer evidence for three independent instances of saltational evolution in a charismatic moth genus with only eight species. Maximum parsimony, maximum likelihood and Bayesian search criteria offered congruent, well supported phylogenies based on 1,965 base pairs of DNA sequence using the mitochondrial gene cytochrome oxidase subunit I, and the nuclear genes elongation factor-1 alpha and wingless. Using a comparative methods approach, we examined three taxa exhibiting novelty in the form of Batesian mimicry, host plant shift, and dramatic physiological differences in light of the phylogenetic data. All three traits appear to have evolved relatively rapidly and independently in three different species of Proserpinus. Each saltational species exhibits a markedly different and discrete example of discontinuous trait evolution while remaining canalized for other typical traits shared by the rest of the genus. All three saltational taxa show insignificantly different levels of overall genetic change as compared with their congeners, implying that their divergence is targeted to particular traits and not genome-wide. Such rapid evolution of novel traits in individual species suggests that the pace of evolution can be quick, dramatic, and isolated--even on the species level. These results may be applicable to other groups in which specific taxa have generated pronounced evolutionary novelty. Genetic mechanisms and methods for assessing such relatively rapid changes are postulated.

  2. Evidence of Repeated and Independent Saltational Evolution in a Peculiar Genus of Sphinx Moths (Proserpinus: Sphingidae)

    PubMed Central

    Rubinoff, Daniel; Le Roux, Johannes J.

    2008-01-01

    Background Saltational evolution in which a particular lineage undergoes relatively rapid, significant, and unparalleled change as compared with its closest relatives is rarely invoked as an alternative model to the dominant paradigm of gradualistic evolution. Identifying saltational events is an important first-step in assessing the importance of this discontinuous model in generating evolutionary novelty. We offer evidence for three independent instances of saltational evolution in a charismatic moth genus with only eight species. Methodology/Principal Findings Maximum parsimony, maximum likelihood and Bayesian search criteria offered congruent, well supported phylogenies based on 1,965 base pairs of DNA sequence using the mitochondrial gene cytochrome oxidase subunit I, and the nuclear genes elongation factor-1 alpha and wingless. Using a comparative methods approach, we examined three taxa exhibiting novelty in the form of Batesian mimicry, host plant shift, and dramatic physiological differences in light of the phylogenetic data. All three traits appear to have evolved relatively rapidly and independently in three different species of Proserpinus. Each saltational species exhibits a markedly different and discrete example of discontinuous trait evolution while remaining canalized for other typical traits shared by the rest of the genus. All three saltational taxa show insignificantly different levels of overall genetic change as compared with their congeners, implying that their divergence is targeted to particular traits and not genome-wide. Conclusions/Significance Such rapid evolution of novel traits in individual species suggests that the pace of evolution can be quick, dramatic, and isolated—even on the species level. These results may be applicable to other groups in which specific taxa have generated pronounced evolutionary novelty. Genetic mechanisms and methods for assessing such relatively rapid changes are postulated. PMID:19107205

  3. Bad math in Linnaeus' Philosophia Botanica.

    PubMed

    Podani, János; Szilágyi, András

    2016-09-01

    In Philosophia Botanica (1751), Carolus Linnaeus (1707-1778) presented a calculation of the number of plant genera that may be distinguished based on his taxonomic concepts. In order to derive that number, he relied upon the organs of fructification, which represent the flower and the fruit, by selecting over 30 elements from them, and then assuming that each could vary by four dimensions. However, while Linnaeus was good in counting stamens and pistils, he and many of his followers who edited or translated Philosophia Botanica were less careful, basing their calculations of the number of possible genera on flawed assumptions, or even introducing basic arithmetic errors. Furthermore, although mathematics was quite advanced in the eighteenth century, the gap between combinatorial and botanical thinking was too deep, preventing Linnaeus to seek a reasonable solution to the problem he raised. The authors demonstrate this by a historical analysis of 15 editions of Philosophia Botanica, plus many references to it, and conclude that the desired number almost always appeared in error during the past 265 years. The German botanist J. G. Gleditsch (1714-1786) was the most successful with respect to Linnaeus' original intention. Elementary mathematics demonstrates that if Linnaeus' assumptions were taken seriously, then the possible number of genera would be astronomical. The practice he followed in Genera Plantarum (1754) shows, however, that the fructification dimensions served as a universal set for Linnaeus from which he chose only the relevant ones for describing a particular genus empirically. Based on the corrections and modifications implemented in reworked editions, we suggest an evolutionary network for the historical and modern versions or translations of Philosophia Botanica.

  4. Evidence for discrete solar and lunar orientation mechanisms in the beach amphipod, Talitrus saltator Montagu (Crustacea, Amphipoda)

    PubMed Central

    Ugolini, Alberto; Hoelters, Laura S.; Ciofini, Alice; Pasquali, Vittorio; Wilcockson, David C.

    2016-01-01

    Animals that use astronomical cues to orientate must make continuous adjustment to account for temporal changes in azimuth caused by Earth’s rotation. For example, the Monarch butterfly possesses a time-compensated sun compass dependent upon a circadian clock in the antennae. The amphipod Talitrus saltator possesses both a sun compass and a moon compass. We reasoned that the time-compensated compass mechanism that enables solar orientation of T. saltator is located in the antennae, as is the case for Monarch butterflies. We examined activity rhythms and orientation of sandhoppers with antennae surgically removed, or unilaterally occluded with black paint. Removing or painting the antennae did not affect daily activity rhythms or competence to orientate using the sun. However, when tested at night these animals were unable to orientate correctly to the moon. We subsequently measured circadian gene expression in the antennae and brain of T. saltator and show the clock genes period and cryptochrome 2 are rhythmically expressed in both tissues, reminiscent of other arthropods known to possess antennal clocks. Together, our behavioural and molecular data suggest that, T. saltator has anatomically discrete lunar and solar orientation apparatus; a sun compass, likely located in the brain and a moon compass in the antennae. PMID:27759059

  5. Evidence for discrete solar and lunar orientation mechanisms in the beach amphipod, Talitrus saltator Montagu (Crustacea, Amphipoda)

    NASA Astrophysics Data System (ADS)

    Ugolini, Alberto; Hoelters, Laura S.; Ciofini, Alice; Pasquali, Vittorio; Wilcockson, David C.

    2016-10-01

    Animals that use astronomical cues to orientate must make continuous adjustment to account for temporal changes in azimuth caused by Earth’s rotation. For example, the Monarch butterfly possesses a time-compensated sun compass dependent upon a circadian clock in the antennae. The amphipod Talitrus saltator possesses both a sun compass and a moon compass. We reasoned that the time-compensated compass mechanism that enables solar orientation of T. saltator is located in the antennae, as is the case for Monarch butterflies. We examined activity rhythms and orientation of sandhoppers with antennae surgically removed, or unilaterally occluded with black paint. Removing or painting the antennae did not affect daily activity rhythms or competence to orientate using the sun. However, when tested at night these animals were unable to orientate correctly to the moon. We subsequently measured circadian gene expression in the antennae and brain of T. saltator and show the clock genes period and cryptochrome 2 are rhythmically expressed in both tissues, reminiscent of other arthropods known to possess antennal clocks. Together, our behavioural and molecular data suggest that, T. saltator has anatomically discrete lunar and solar orientation apparatus; a sun compass, likely located in the brain and a moon compass in the antennae.

  6. Carl Linnaeus and the visual representation of nature.

    PubMed

    Charmantier, Isabelle

    2011-01-01

    The Swedish naturalist Carl Linnaeus (1707-1778) is reputed to have transformed botanical practice by shunning the process of illustrating plants and relying on the primacy of literary descriptions of plant specimens. Botanists and historians have long debated Linnaeus's capacities as a draftsman. While some of his detailed sketches of plants and insects reveal a sure hand, his more general drawings of landscapes and people seem ill-executed. The overwhelming consensus, based mostly on his Lapland diary (1732), is that Linnaeus could not draw. Little has been said, however, on the role of drawing and other visual representations in Linnaeus's daily work as seen in his other numerous manuscripts. These manuscripts, held mostly at the Linnean Society of London, are peppered with sketches, maps, tables, and diagrams. Reassessing these manuscripts, along with the printed works that also contain illustrations of plant species, shows that Linnaeus's thinking was profoundly visual and that he routinely used visual representational devices in his various publications. This paper aims to explore the full range of visual representations Linnaeus used through his working life, and to reevaluate the epistemological value of visualization in the making of natural knowledge. By analyzing Linnaeus's use of drawings, maps, tables, and diagrams, I will show that he did not, as has been asserted, reduce the discipline of botany to text, and that his visual thinking played a fundamental role in his construction of new systems of classification.

  7. Simulation of Effects of the Saffman Force and the Magnus Force on Sand Saltation in Turbulent Flow

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

    Zheng, Zhongquan C.; Zou, Xueyong; Yang, Xiaofan

    2011-12-11

    The effects of both the Saffman force and Magnus force on sand saltation are investigated. Turbulent flows in a channel and over a barchans dune are considered with sand particles injected into the flow. The results show that both of the forces increase the height and skipping distance of sand saltation, with the Magnus force giving more significant effect on the height. These forces can also increase the sand settling at the lee side of the barchans dune.

  8. Does the Auditory Saltation Stimulus Distinguish Dyslexic from Competently Reading Adults?

    ERIC Educational Resources Information Center

    Kidd, Joanna C.; Hogben, John H.

    2007-01-01

    Purpose: Where the auditory saltation illusion has been used as a measure of auditory temporal processing (ATP) in dyslexia, conflicting results have been apparent (cf. R. Hari & P. Kiesila, 1996; M. Kronbichler, F. Hutzler, & H. Wimmer, 2002). This study sought to re-examine these findings by investigating whether dyslexia is characterized by…

  9. Intrachromosomal rearrangements in two representatives of the genus Saltator (Thraupidae, Passeriformes) and the occurrence of heteromorphic Z chromosomes.

    PubMed

    dos Santos, Michelly da Silva; Kretschmer, Rafael; Silva, Fabio Augusto Oliveira; Ledesma, Mario Angel; O'Brien, Patricia C M; Ferguson-Smith, Malcolm A; Del Valle Garnero, Analía; de Oliveira, Edivaldo Herculano Corrêa; Gunski, Ricardo José

    2015-10-01

    Saltator is a genus within family Thraupidae, the second largest family of Passeriformes, with more than 370 species found exclusively in the New World. Despite this, only a few species have had their karyotypes analyzed, most of them only with conventional staining. The diploid number is close to 80, and chromosome morphology is similar to the usual avian karyotype. Recent studies using cross-species chromosome painting have shown that, although the chromosomal morphology and number are similar to many species of birds, Passeriformes exhibit a complex pattern of paracentric and pericentric inversions in the chromosome homologous to GGA1q in two different suborders, Oscines and Suboscines. Hence, considering the importance and species richness of Thraupidae, this study aims to analyze two species of genus Saltator, the golden-billed saltator (S. aurantiirostris) and the green-winged saltator (S. similis) by means of classical cytogenetics and cross-species chromosome painting using Gallus gallus and Leucopternis albicollis probes, and also 5S and 18S rDNA and telomeric sequences. The results show that the karyotypes of these species are similar to other species of Passeriformes. Interestingly, the Z chromosome appears heteromorphic in S. similis, varying in morphology from acrocentric to metacentric. 5S and 18S probes hybridize to one pair of microchromosomes each, and telomeric sequences produce signals only in the terminal regions of chromosomes. FISH results are very similar to the Passeriformes already analyzed by means of molecular cytogenetics (Turdus species and Elaenia spectabilis). However, the paracentric and pericentric inversions observed in Saltator are different from those detected in these species, an observation that helps to explain the probable sequence of rearrangements. As these rearrangements are found in both suborders of Passeriformes (Oscines and Suboscines), we propose that the fission of GGA1 and inversions in GGA1q have occurred very

  10. In the field: exploring nature with Carolus Linnaeus.

    PubMed

    Hodacs, Hanna

    2010-06-01

    Teaching his students the art of observing nature outdoors was central to the Swedish naturalist Carolus (Carl) Linnaeus (1707-1778). These exercises came to influence both their progress and his work. The open-air classroom was a stage where Linnaeus could demonstrate his skills and mobilize support. It was also a testing, training and recruitment ground: the students' field observations helped Linnaeus to develop his new scientific nomenclature, and it was in the field that students could train their observational skills and progress from novices to naturalists. Copyright 2009. Published by Elsevier Ltd.

  11. Saltation under Martian gravity and its influence on the global dust distribution

    NASA Astrophysics Data System (ADS)

    Musiolik, Grzegorz; Kruss, Maximilian; Demirci, Tunahan; Schrinski, Björn; Teiser, Jens; Daerden, Frank; Smith, Michael D.; Neary, Lori; Wurm, Gerhard

    2018-05-01

    Dust and sand motion are a common sight on Mars. Understanding the interaction of atmosphere and Martian soil is fundamental to describe the planet's weather, climate and surface morphology. We set up a wind tunnel to study the lift of a mixture between very fine sand and dust in a Mars simulant soil. The experiments were carried out under Martian gravity in a parabolic flight. The reduced gravity was provided by a centrifuge under external microgravity. The onset of saltation was measured for a fluid threshold shear velocity of 0.82 ± 0.04 m/s. This is considerably lower than found under Earth gravity. In addition to a reduction in weight, this low threshold can be attributed to gravity dependent cohesive forces within the sand bed, which drop by 2/3 under Martian gravity. The new threshold for saltation leads to a simulation of the annual dust cycle with a Mars GCM that is in agreement with observations.

  12. Strong feedbacks between hillslope sediment production and channel incision by saltation-abrasion

    NASA Astrophysics Data System (ADS)

    Lundbek Egholm, David; Faurschou Knudsen, Mads; Sandiford, Mike

    2013-04-01

    While it is well understood that rivers erode mountain ranges by incising the bedrock and by transporting sediments away from the ranges, the basic physical mechanisms that drive long-term bedrock erosion and control the lifespan of mountain ranges remain uncertain. A particularly challenging paradox is reconciling the dichotomy associated with the high incision rates observed in active mountain belts, and the long-term (108 years) preservation of significant topographic reliefs in inactive orogenic belts (e.g. von Blankenburg, 2005). We have performed three-dimensional computational experiments with a landscape evolution model that couples bedrock landslides and sediment flux-dependent river erosion by saltation-abrasion (Sklar & Dietrich, 2004). The coupled model experiments show strong feedbacks between the channel erosion and the hillslope delivery of sediments. The feedbacks point to hillslope sediment production rate as the main control on channel erosion rates where saltation-abrasion dominates over other fluvial erosion processes. Our models results thus highlight the importance of hillslope sediment production controlled by climate and tectonic activity for scaling erosion rates in fluvial systems. Because of variations in landslide frequency, the feedbacks make tectonic activity a primary driver of fluvial erosion and help clarifying the long-standing paradox associated with the persistence of significant relief in old orogenic belts, up to several hundred-million-years after tectonic activity has effectively ceased. References F. von Blankenburg. The control mechanisms of erosion and weathering at basin scale from cosmogenic nuclides in river sediment. Earth Planet. Sci. Lett. 237, 462-479 (2005). L. S. Sklar, W. E. Dietrich. A mechanistic model for river incision into bedrock by saltating bed load. Water Resour. Res. 40, W06301 (2004).

  13. Saltation movement of large spherical particles

    NASA Astrophysics Data System (ADS)

    Chara, Z.; Dolansky, J.; Kysela, B.

    2017-07-01

    The paper presents experimental and numerical investigations of the saltation motion of a large spherical particle in an open channel. The channel bottom was roughed by one layer of glass rods of diameter 6 mm. The plastic spheres of diameter 25.7 mm and density 1160 kgm-3 were fed into the water channel and theirs positions were viewed by a digital camera. Two light sheets were placed above and under the channel, so the flow was simultaneously lighted from the top and the bottom. Only particles centers of which moved through the light sheets were recorded. Using a 2D PIV method the trajectories of the spheres and the velocity maps of the channel flow were analyzed. The Lattice-Boldzmann Method (LBM) was used to simulate the particle motion.

  14. Identification and temporal expression of putative circadian clock transcripts in the amphipod crustacean Talitrus saltator

    PubMed Central

    O’Grady, Joseph F.; Hoelters, Laura S.; Swain, Martin T.

    2016-01-01

    Background Talitrus saltator is an amphipod crustacean that inhabits the supralittoral zone on sandy beaches in the Northeast Atlantic and Mediterranean. T. saltator exhibits endogenous locomotor activity rhythms and time-compensated sun and moon orientation, both of which necessitate at least one chronometric mechanism. Whilst their behaviour is well studied, currently there are no descriptions of the underlying molecular components of a biological clock in this animal, and very few in other crustacean species. Methods We harvested brain tissue from animals expressing robust circadian activity rhythms and used homology cloning and Illumina RNAseq approaches to sequence and identify the core circadian clock and clock-related genes in these samples. We assessed the temporal expression of these genes in time-course samples from rhythmic animals using RNAseq. Results We identified a comprehensive suite of circadian clock gene homologues in T. saltator including the ‘core’ clock genes period (Talper), cryptochrome 2 (Talcry2), timeless (Taltim), clock (Talclk), and bmal1 (Talbmal1). In addition we describe the sequence and putative structures of 23 clock-associated genes including two unusual, extended isoforms of pigment dispersing hormone (Talpdh). We examined time-course RNAseq expression data, derived from tissues harvested from behaviourally rhythmic animals, to reveal rhythmic expression of these genes with approximately circadian period in Talper and Talbmal1. Of the clock-related genes, casein kinase IIβ (TalckIIβ), ebony (Talebony), jetlag (Taljetlag), pigment dispensing hormone (Talpdh), protein phosphatase 1 (Talpp1), shaggy (Talshaggy), sirt1 (Talsirt1), sirt7 (Talsirt7) and supernumerary limbs (Talslimb) show temporal changes in expression. Discussion We report the sequences of principle genes that comprise the circadian clock of T. saltator and highlight the conserved structural and functional domains of their deduced cognate proteins. Our

  15. Incident angle of saltating particles in wind-blown sand.

    PubMed

    Fu, Lin-Tao; Bo, Tian-Li; Gu, Hai-Hua; Zheng, Xiao-Jing

    2013-01-01

    Incident angle of saltating particles plays a very important role in aeolian events. In this paper, the incident angles of sand particles near the sand bed were measured in wind tunnel. It reveals that the incident angles range widely from 0° to 180° and thereby the means of angles are larger than published data. Surprisingly, it is found the proportion that angles of 5°-15° occupy is far below previous reports. The measuring height is probably the most important reason for the measurement differences between this study and previous investigations.

  16. Linnaeus in Uppsala, Sweden.

    ERIC Educational Resources Information Center

    Cohen, Paul; Cohen, Brenda

    1997-01-01

    Presents a brief life history of Carl Linnaeus, a professor of medicine and botany in Uppsala, Sweden. Highlights his work in developing a classification system for plants and animals, and his botanical lectures and demonstrations. (JRH)

  17. Incident Angle of Saltating Particles in Wind-Blown Sand

    PubMed Central

    Fu, Lin-Tao; Bo, Tian-Li; Gu, Hai-Hua; Zheng, Xiao-Jing

    2013-01-01

    Incident angle of saltating particles plays a very important role in aeolian events. In this paper, the incident angles of sand particles near the sand bed were measured in wind tunnel. It reveals that the incident angles range widely from 0° to 180° and thereby the means of angles are larger than published data. Surprisingly, it is found the proportion that angles of 5°–15° occupy is far below previous reports. The measuring height is probably the most important reason for the measurement differences between this study and previous investigations. PMID:23874470

  18. Threshold Velocity for Saltation Activity in the Taklimakan Desert

    NASA Astrophysics Data System (ADS)

    Yang, Xinghua; He, Qing; Matimin, Ali; Yang, Fan; Huo, Wen; Liu, Xinchun; Zhao, Tianliang; Shen, Shuanghe

    2017-12-01

    The threshold velocity is an indicator of a soil's susceptibility to saltation activity and is also an important parameter in dust emission models. In this study, the saltation activity, atmospheric conditions, and soil conditions were measured from 1 August 2008 to 31 July 2009 in the Taklimakan Desert, China. the threshold velocity was estimated using the Gaussian time fraction equivalence method. At 2 m height, the 1-min averaged threshold velocity varied between 3.5 and 10.9 m/s, with a mean of 5.9 m/s. Threshold velocities varying between 4.5 and 7.5 m/s accounted for about 91.4% of all measurements. The average threshold velocity displayed clear seasonal variations in the following sequence: winter (5.1 m/s) < autumn (5.8 m/s) < spring (6.1 m/s) < summer (6.5 m/s). A regression equation of threshold velocity was established based on the relations between daily mean threshold velocity and air temperature, specific humidity, and soil volumetric moisture content. High or moderate positive correlations were found between threshold velocity and air temperature, specific humidity, and soil volumetric moisture content (air temperature r = 0.75; specific humidity r = 0.59; and soil volumetric moisture content r = 0.55; sample size = 251). In the study area, the observed horizontal dust flux was 4198.0 kg/m during the whole period of observation, while the horizontal dust flux calculated using the threshold velocity from the regression equation was 4675.6 kg/m. The correlation coefficient between the calculated result and the observations was 0.91. These results indicate that atmospheric and soil conditions should not be neglected in parameterization schemes for threshold velocity.

  19. Potential Use of BEST® Sediment Trap in Splash - Saltation Transport Process by Simultaneous Wind and Rain Tests

    PubMed Central

    Basaran, Mustafa; Uzun, Oguzhan; Cornelis, Wim; Gabriels, Donald; Erpul, Gunay

    2016-01-01

    The research on wind-driven rain (WDR) transport process of the splash-saltation has increased over the last twenty years as wind tunnel experimental studies provide new insights into the mechanisms of simultaneous wind and rain (WDR) transport. The present study was conducted to investigate the efficiency of the BEST® sediment traps in catching the sand particles transported through the splash-saltation process under WDR conditions. Experiments were conducted in a wind tunnel rainfall simulator facility with water sprayed through sprinkler nozzles and free-flowing wind at different velocities to simulate the WDR conditions. Not only for vertical sediment distribution, but a series of experimental tests for horizontal distribution of sediments was also performed using BEST® collectors to obtain the actual total sediment mass flow by the splash-saltation in the center of the wind tunnel test section. Total mass transport (kg m-2) were estimated by analytically integrating the exponential functional relationship using the measured sediment amounts at the set trap heights for every run. Results revealed the integrated efficiency of the BEST® traps at 6, 9, 12 and 15 m s-1 wind velocities under 55.8, 50.5, 55.0 and 50.5 mm h-1 rain intensities were, respectively, 83, 106, 105, and 102%. Results as well showed that the efficiencies of BEST® did not change much as compared with those under rainless wind condition. PMID:27898716

  20. Potential Use of BEST® Sediment Trap in Splash - Saltation Transport Process by Simultaneous Wind and Rain Tests.

    PubMed

    Basaran, Mustafa; Uzun, Oguzhan; Cornelis, Wim; Gabriels, Donald; Erpul, Gunay

    2016-01-01

    The research on wind-driven rain (WDR) transport process of the splash-saltation has increased over the last twenty years as wind tunnel experimental studies provide new insights into the mechanisms of simultaneous wind and rain (WDR) transport. The present study was conducted to investigate the efficiency of the BEST® sediment traps in catching the sand particles transported through the splash-saltation process under WDR conditions. Experiments were conducted in a wind tunnel rainfall simulator facility with water sprayed through sprinkler nozzles and free-flowing wind at different velocities to simulate the WDR conditions. Not only for vertical sediment distribution, but a series of experimental tests for horizontal distribution of sediments was also performed using BEST® collectors to obtain the actual total sediment mass flow by the splash-saltation in the center of the wind tunnel test section. Total mass transport (kg m-2) were estimated by analytically integrating the exponential functional relationship using the measured sediment amounts at the set trap heights for every run. Results revealed the integrated efficiency of the BEST® traps at 6, 9, 12 and 15 m s-1 wind velocities under 55.8, 50.5, 55.0 and 50.5 mm h-1 rain intensities were, respectively, 83, 106, 105, and 102%. Results as well showed that the efficiencies of BEST® did not change much as compared with those under rainless wind condition.

  1. Carl Linnaeus: pictures and propaganda.

    PubMed

    Fara, Patricia

    2003-03-01

    How do scientists become famous? Carl Linnaeus was an expert at self-promotion who used portraits to gain patronage and consolidate his reputation. His sexualized classification system was hugely controversial, yet his successors celebrated him as a great hero of botany.

  2. Aeolian Erosion on Mars - a New Threshold for Saltation

    NASA Astrophysics Data System (ADS)

    Teiser, J.; Musiolik, G.; Kruss, M.; Demirci, T.; Schrinski, B.; Daerden, F.; Smith, M. D.; Neary, L.; Wurm, G.

    2017-12-01

    The Martian atmosphere shows a large variety of dust activity, ranging from local dust devils to global dust storms. Also, sand motion has been observed in form of moving dunes. The dust entrainment into the Martian atmosphere is not well understood due to the small atmospheric pressure of only a few mbar. Laboratory experiments on Earth and numerical models were developed to understand these processes leading to dust lifting and saltation. Experiments so far suggested that large wind velocities are needed to reach the threshold shear velocity and to entrain dust into the atmosphere. In global circulation models this threshold shear velocity is typically reduced artificially to reproduce the observed dust activity. Although preceding experiments were designed to simulate Martian conditions, no experiment so far could scale all parameters to Martian conditions, as either the atmospheric or the gravitational conditions were not scaled. In this work, a first experimental study of saltation under Martian conditions is presented. Martian gravity is reached by a centrifuge on a parabolic flight, while pressure (6 mbar) and atmospheric composition (95% CO2, 5% air) are adjusted to Martian levels. A sample of JSC 1A (grain sizes from 10 - 100 µm) was used to simulate Martian regolith. The experiments showed that the reduced gravity (0.38 g) not only affects the weight of the dust particles, but also influences the packing density within the soil and therefore also the cohesive forces. The measured threshold shear velocity of 0.82 m/s is significantly lower than the measured value for 1 g in ground experiments (1.01 m/s). Feeding the measured value into a Global Circulation Model showed that no artificial reduction of the threshold shear velocity might be needed to reproduce the global dust distribution in the Martian atmosphere.

  3. Linnaeus' study of Swedish swidden cultivation: Pioneering ethnographic work on the 'economy of nature'.

    PubMed

    Dove, Michael R

    2015-04-01

    Carl Linnaeus' work on the 'economy of nature' was a major early development in what became the modern field of ecology. This analysis suggests that a key subject of this work that has been ignored or misunderstood for 250 years is the rural livelihoods, especially swidden (or slash-and-burn) agriculture, which Linnaeus studied during his expeditions through rural Sweden. Rereading his reports in the light of modern work on swiddens, political ecology, and the history of science affords a new appreciation of Linnaeus' insights into traditional systems of resource exploitation. The logic of nutrient cycling in swidden agriculture and its utilization of natural dynamics to serve human ends exemplify the principles of the 'economy of nature', and gave Linnaeus a philosophical basis for understanding and defending this system of agriculture as well as other rural resource use systems in Sweden. This analysis sheds new light on Linnaeus' ethnographic work, his view of folk environmental knowledge, and his often derided identification with Sweden's ethnic peoples.

  4. Amyloplast sedimentation and organelle saltation in living corn columella cells

    NASA Technical Reports Server (NTRS)

    Sack, F. D.; Suyemoto, M. M.; Leopold, A. C.

    1986-01-01

    Amyloplast sedimentation during gravistimulation and organelle movements was studied in living central rootcap cells of Zea mays L. cv. Merit. Cells from sectioned roots were viewed with a horizontally-mounted videomicroscope. The kinetics of gravity-induced amyloplast sedimentation were comparable to those calculated from experiments using fixed material. Individual amyloplasts fell at an average velocity of 5.5 micrometers min-1; the maximal velocity of fall measured was 18.0 micrometers min-1. Amyloplasts often rotated, sometimes rose in the cytoplasm, and occasionally underwent sudden rapid movements as fast as 58 micrometers min-1. Saltations of other organelles were frequently observed. This appears to be the first report of cytoplasmic streaming in the presumptive statocytes of roots.

  5. Linnaeus' herbarium cabinet: a piece of furniture and its function.

    PubMed

    Müller-Wille, Staffan

    2006-06-01

    The Swedish 18th-century naturalist Carolus (Carl) Linnaeus is habitually credited with laying the foundations of modern taxonomy through the invention of binominal nomenclature. However, another innovation of Linnaeus' has largely gone unnoticed. He seems to have been one of the first botanists to leave his herbarium unbound, keeping the sheets of dried plants separate and stacking them in a purpose built-cabinet. Understanding the significance of this seemingly mundane and simple invention opens a window onto the profound changes that natural history underwent in the 18th century.

  6. Seasonal variation in the free-running period in two Talitrus saltator populations from Italian beaches differing in morphodynamics and human disturbance

    NASA Astrophysics Data System (ADS)

    Nardi, M.; Morgan, E.; Scapini, F.

    2003-10-01

    The sandhopper Talitrus saltator Montagu (Amphipoda) is a widespread species adapted to different changing environmental conditions and which typically shows a clear circadian rhythm of locomotor activity. The populations from two beaches on the western Italian coast differing in coastline dynamics (eroded versus dynamically stable) and human disturbance (inside a natural park versus freely used and cleaned for leisure) were studied to highlight intrapopulation variation in the endogenous locomotor rhythm. The activity of adult sandhoppers was studied under constant laboratory conditions within individual recording chambers. Variation of the free-running period was analysed at individual level within each population. Greater variability was found than previously reported for the circadian rhythm period of T. saltator, and seasonal variation was shown for the first time. Differences in the level of variation were correlated with coastline dynamics.

  7. The behavioural ecology of two sympatric talitrid species, Talitrus saltator (Montagu) and Orchestia gammarellus (Pallas) on a Tyrrhenian sandy beach dune system

    NASA Astrophysics Data System (ADS)

    Colombini, Isabella; Fallaci, Mario; Gagnarli, Elena; Rossano, Claudia; Scapini, Felicita; Chelazzi, Lorenzo

    2013-01-01

    The behavioural ecology of a sub-population of Talitrus saltator living on the sandy shore of the Maremma Regional Park (Italy) was compared with that of Orchestia gammarellus inhabiting the retrodunal dune slack area. Monthly monitoring over a year determined the mean distribution patterns, their changes and whether these overlapped. Standard pitfall traps were placed along transects across the beach-dune-dune slack area. Experiments analysed the diel activity rhythms during spring and the activity patterns of the different age classes and the two sexes were compared within and between species. Local environmental conditions were registered with a microclimatic station. During May and September, plant hummocks were monitored to see whether surface movements of O. gammarellus could be restricted to certain periods of the year and to estimate densities within the vegetation. The plant biomass and moisture conditions within the hummocks were also recorded and substratum samples were collected at the base of the shrubs for laboratory analysis. To test for visual cues, orientation experiments with and without landscape view were carried out on the beach during morning and afternoon hours and contemporaneously for each species. Experiments to test the diel variation of scototaxis to a black shape were also performed over a 24 h period of time under controlled conditions. There was a spatial partitioning of the two species, with T. saltator moving along a sea-land axis according to diel and seasonal changes and with some individuals reaching the back of the dune in particular environmental conditions. No spatial overlap with the zonation patterns of O. gammarellus was observed, which was restricted to the dune slack area. Nocturnal surface activity was observed for both species with juveniles peaking at dawn and with O. gammarellus being strictly more nocturnal than T. saltator. Orientation experiments showed a higher ability of T. saltator to orient towards the

  8. An experimental study of the dynamics of saltation within a three-dimensional framework

    NASA Astrophysics Data System (ADS)

    O'Brien, Patrick; McKenna Neuman, Cheryl

    2018-04-01

    Our understanding of aeolian sand transport via saltation lacks an experimental determination of the particle borne kinetic energy partitioned into 3 dimensions relative to the mean flow direction. This in turn creates a disconnect between global wind erosion estimates and particle scale processes. The present study seeks to address this deficiency through an extended analysis of data obtained from a series of particle tracking velocimetry experiments conducted in a boundary layer wind tunnel under transport limited conditions. Particle image diameter, as it appeared within each camera frame, was extensively calibrated against that obtained by sieving, and the ballistic trajectories detected were disassembled into discrete particle image pairs whose distribution and dynamics were then examined in vertical profile with sub-millimeter resolution. The vertical profile of the wind aligned particle transport rate was found to follow a power relation within 10 mm of the bed surface. The exponent of this power function changes with increasing spanwise angle (θ) to produce a family of curves representing particle diffusion in 3 dimensions. Particle mass was found to increase with θ, and the distribution of the total particle kinetic energy was found to be very similar to that for the particle concentration. The spanwise component of the kinetic energy of a saltating particle peaks at θ = 45°, with the stream-aligned component an order of magnitude higher in value. Low energy, splashed particles near the bed account for a majority of the kinetic energy distributed throughout the particle cloud, regardless of their orientation.

  9. Feature saltation and the evolution of mimicry.

    PubMed

    Gamberale-Stille, Gabriella; Balogh, Alexandra C V; Tullberg, Birgitta S; Leimar, Olof

    2012-03-01

    In Batesian mimicry, a harmless prey species imitates the warning coloration of an unpalatable model species. A traditional suggestion is that mimicry evolves in a two-step process, in which a large mutation first achieves approximate similarity to the model, after which smaller changes improve the likeness. However, it is not known which aspects of predator psychology cause the initial mutant to be perceived by predators as being similar to the model, leaving open the question of how the crucial first step of mimicry evolution occurs. Using theoretical evolutionary simulations and reconstruction of examples of mimicry evolution, we show that the evolution of Batesian mimicry can be initiated by a mutation that causes prey to acquire a trait that is used by predators as a feature to categorize potential prey as unsuitable. The theory that species gain entry to mimicry through feature saltation allows us to formulate scenarios of the sequence of events during mimicry evolution and to reconstruct an initial mimetic appearance for important examples of Batesian mimicry. Because feature-based categorization by predators entails a qualitative distinction between nonmimics and passable mimics, the theory can explain the occurrence of imperfect mimicry. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

  10. Field Calibration of the Saltation-Abrasion Model Using Measurements of the Energy Delivered to the Channel Bed

    NASA Astrophysics Data System (ADS)

    Turowski, J. M.; Wyss, C. R.; Beer, A. R.

    2014-12-01

    The saltation-abrasion model (SAM) is one of the highest-developed process models for fluvial bedrock erosion, describing bedrock erosion due to the impact of saltating bedload particles. The fundamental assumption in the model is a proportionality of the erosion rate and the energy delivered to the channel bed by these impacts. So far, the SAM has been calibrated on laboratory data, but field tests are rare. Here, we exploit the availability of high-quality field data at the Erlenbach bedload observatory to test and calibrate the SAM. The Erlenbach is a small, steep stream in the Swiss Prealps that hosts a well-instrumented observatory for bedload transport and erosion. Bedload samples can be taken during floods with automatic basket samplers and bedload transport rates are measured continuously with Swiss plate geophones, a surrogate method for bedload monitoring. The geophone plates can also be used to measure the energy transferred to the bed by passingbedload. Thus, we can calibrate the SAM by exploiting independent data on particle impacts, the energy they transfer to the bed, and bedload samples including grain size distributions. We find that the dimensionless pre-factor to the model is dependent on grain size. Predictions of bedrock erosion can be compared to spatial erosion data obtained from successive scans of bedrock slabs installed in the channel bed immediately upstream of the plate geophones.

  11. A Non-Proteinaceious Toxin from the Venomous Spines of the Lionfish Pterois Volitans (Linnaeus)

    DTIC Science & Technology

    1985-01-01

    Spines of the Lionfish Pterois Volitans (Linnaeus) 6. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(a) S. CONTRACT OR GRANT NUMBER(&) Nair, M.S.R. Cheung, P...and Identify by block number) Tinon Lionfish , Non-Proteinaceous Toxin, Ichthyotoxin 20. A9ST’ACT ? ( mt.e ,vmM N , mid ify by block nusmber) "!;The...COMMUNICATIONS A NON-PROTEINACEOUS TOXIN FROM THE VENOMOUS SPINES OF THE LIONFISH PTEROIS VOLITANS (LINNAEUS) 2 20 M. S. R. NAIR,’ PAUL CHEUNG, INA

  12. LINNAEUS: BOOSTING NEAR EARTH ASTEROID CHARACTERIZATION RATES

    NASA Astrophysics Data System (ADS)

    Elvis, Martin; Beeson, C.; Galache, J.; DeMeo, F.; Evans, I.; Evans, J.; Konidaris, N.; Najita, J.; Allen, L.; Christensen, E.; Spahr, T.

    2013-10-01

    Near Earth objects (NEOs) are being discovered at a rate of about 1000 per year, and this rate is set to double by 2015. However, the physical characterization of NEOs is only ~100 per year for each type of follow-up observation. We have proposed the LINNAEUS program to NASA to raise the characterization rate of NEOs to the rate of their discovery. This rate matching is necessary as any given NEO is only available for a relatively short time (days to weeks), and they are usually fainter on subsequent apparitions. Hence follow-up observations must be initiated rapidly, without time to cherry-pick the optimum objects. LINNAEUS concentrates on NEO composition. Optical spectra, preferably extending into the near-infrared, provide compositions that can distinguish major compositional classes of NEOs with reasonable confidence (Bus and Binzel 2002, DeMeo et al. 2009). Armed with a taxonomic type the albedo, pV, of an NEO is better constrained, leading to more accurate sizes and masses. Time-resolved spectroscopy can give indications of period, axial ratio and surface homogeneity. A reasonable program of spectroscopy could keep pace with the NEO discovery rate. A ground-based telescope can observe faint NEOs about 210 nights a year, due to time lost due to weather, bright time, and equipment downtime (e.g. Gemini), for a total of ~2000 hours/year. At 1 hour per NEO spectrum, a well-run, dedicated, telescope could obtain almost 2000 spectra per year, about the rate required. If near-IR spectra are required then a 4 m or larger telescope is necessary to reach 20. However, if the Bus-Binzel taxomonmy suffices then only optical spectra are needed and a 2 meter class telescope is sufficient. LINNAEUS would use 50% of the KPNO 2.1 m telescope with an IFU spectrometer, the SED-machine (Ben-Ami et al. 2013), to obtain time-resolved optical spectra of 1200-2000 NEOs/year, or 4200-7000 in 3.5 years observing in an NEOO program. Robust pipeline analysis will release taxonomic types

  13. Longitudinal data for interdisciplinary ageing research. Design of the Linnaeus Database.

    PubMed

    Malmberg, Gunnar; Nilsson, Lars-Göran; Weinehall, Lars

    2010-11-01

    To allow for interdisciplinary research on the relations between socioeconomic conditions and health in the ageing population, a new anonymized longitudinal database - the Linnaeus Database - has been developed at the Centre for Population Studies at Umeå University. This paper presents the database and its research potential. Using the Swedish personal numbers the researchers have, in collaboration with Statistics Sweden and the National Board for Health and Welfare, linked individual records from Swedish register data on death causes, hospitalization and various socioeconomic conditions with two databases - Betula and VIP (Västerbottens Intervention Programme) - previously developed by the researchers at Umeå University. Whereas Betula includes rich information about e.g. cognitive functions, VIP contains information about e.g. lifestyle and health indicators. The Linnaeus Database includes annually updated socioeconomic information from Statistics Sweden registers for all registered residents of Sweden for the period 1990 to 2006, in total 12,066,478. The information from the Betula includes 4,500 participants from the city of Umeå and VIP includes data for almost 90,000 participants. Both datasets include cross-sectional as well as longitudinal information. Due to the coverage and rich information, the Linnaeus Database allows for a variety of longitudinal studies on the relations between, for instance, socioeconomic conditions, health, lifestyle, cognition, family networks, migration and working conditions in ageing cohorts. By joining various datasets developed in different disciplinary traditions new possibilities for interdisciplinary research on ageing emerge.

  14. Trajectories and energy transfer of saltating particles onto rock surfaces : application to abrasion and ventifact formation on Earth and Mars

    NASA Technical Reports Server (NTRS)

    Bridges, Nathan T.; Phoreman, James; White, Bruce R.; Greeley, Ronald; Eddlemon, Eric E.; Wilson, Gregory R.; Meyer, Christine J.

    2005-01-01

    The interaction between saltating sand grains and rock surfaces is assessed to gauge relative abrasion potential as a function of rock shape, wind speed, grain size, and planetary environment. Many kinetic energy height profiles for impacts exhibit a distinctive increase, or kink, a few centimeters above the surface, consistent with previous field, wind tunnel, and theoretical investigations. The height of the kink observed in natural and wind tunnel settings is greater than predictions by a factor of 2 or more, probably because of enhanced bouncing off hard ground surfaces. Rebounded grains increase the effective flux and relative kinetic energy for intermediate slope angles. Whether abrasion occurs, as opposed to simple grain impact with little or no mass lost from the rock, depends on whether the grain kinetic energy (EG) exceeds a critical value (EC), as well as the flux of grains with energies above EC. The magnitude of abrasion and the shape change of the rock over time depends on this flux and the value of EG > EC. Considering the potential range of particle sizes and wind speeds, the predicted kinetic energies of saltating sand hitting rocks overlap on Earth and Mars. However, when limited to the most likely grain sizes and threshold conditions, our results agree with previous work and show that kinetic energies are about an order of magnitude greater on Mars.

  15. Natural history and information overload: The case of Linnaeus

    PubMed Central

    Müller-Wille, Staffan; Charmantier, Isabelle

    2012-01-01

    Natural History can be seen as a discipline paradigmatically engaged in ‘data-driven research.’ Historians of early modern science have begun to emphasize its crucial role in the Scientific Revolution, and some observers of present day genomics see it as engaged in a return to natural history practices. A key concept that was developed to understand the dynamics of early modern natural history is that of ‘information overload.’ Taxonomic systems, rules of nomenclature, and technical terminologies were developed in botany and zoology to catch up with the ever increasing amount of information on hitherto unknown plant and animal species. In our contribution, we want to expand on this concept. After all, the same people who complain about information overload are usually the ones who contribute to it most significantly. In order to understand this complex relationship, we will turn to the annotation practices of the Swedish naturalist Carl Linnaeus (1707–1778). The very tools that Linnaeus developed to contain and reduce information overload, as we aim to demonstrate, facilitated a veritable information explosion that led to the emergence of a new research object in botany: the so-called ‘natural’ system. PMID:22326068

  16. Linnaeus' restless system: translation as textual engineering in eighteenth-century botany.

    PubMed

    Dietz, Bettina

    2016-04-01

    In this essay, translations of Linnaeus' Systema naturae into various European languages will be placed into the context of successively expanded editions of Linnaeus' writings. The ambition and intention of most translators was not only to make the Systema naturae accessible for practical botanical use by a wider readership, but also to supplement and correct it, and thus to shape it. By recruiting more users, translations made a significant contribution to keeping the Systema up to date and thus maintaining its practical value for decades. The need to incorporate countless additions and corrections into an existing text, to document their provenance, to identify inconsistencies, and to refer to relevant observations, descriptions, and illustrations in the botanical literature all helped to develop and refine techniques of textual montage. This form of textual engineering, becoming increasingly complex with each translation cycle, shaped the external appearance of new editions of the Systema, and reflected the modular architecture of a botanical system designed for expansion.

  17. Antibiotic Action of Solanum incanum Linnaeus

    PubMed Central

    Beaman-Mbaya, V.; Muhammed, S. I.

    1976-01-01

    The fruits of Solanum incanum Linnaeus are extensively used in Kenya for the treatment of cutaneous mycotic infections and other pathological conditions. The therapeutic activity of the berries has been attributed to their content of solanine and related glycoalkaloids, which are saponins and cytostatic poisons. In the present study, however, a simpler more potent antimicrobial substance with a phosphorylated structure similar to the purine adenine was isolated from the berries. The crystals of this compound were effective inhibitors of the growth of gram-positive and -negative bacteria, yeasts, dermatophytes, and some pathogens of agricultural produce. High concentrations of the substance caused hemolysis of erythrocytes. Images PMID:945715

  18. Eighteenth century classification of mental illness: Linnaeus, de Sauvages, Vogel, and Cullen.

    PubMed

    Munsche, Heather; Whitaker, Harry A

    2012-12-01

    Classification was an important aspect of the 17th and 18th century development of Western science, epitomized by Linnaeus's 1735 Systema Naturae (Nature's System), in which he divided each kingdom of nature into classes, orders, and species. Linnaeus, a physician in addition to being a renowned taxonomist, endeavored to classify all known human diseases, largely on the basis of symptoms, in his 1759 Genera Morborum (Varieties of Diseases). We focus on his classification of mental disorders, a large subset of the Genera Morborum. We compare and contrast the Linnaean system with François Boissier de Sauvages's 1772 Nosologie méthodique (A Systematic Nosology) and Rudolph Augustin Vogel's 1764 Generum Morborum (Varieties of Diseases). We consider the impact of these nosologies on William Cullen's (1769/1800) Nosology, a popular system of disease classification that persisted through much of the 19th century.

  19. Trophic ecomorphology of Siluriformes (Pisces, Osteichthyes) from a tropical stream.

    PubMed

    Pagotto, J P A; Goulart, E; Oliveira, E F; Yamamura, C B

    2011-05-01

    The present study analysed the relationship between morphology and trophic structure of Siluriformes (Pisces, Osteichthyes) from the Caracu Stream (22º 45' S and 53º 15' W), a tributary of the Paraná River (Brazil). Sampling was carried out at three sites using electrofishing, and two species of Loricariidae and four of Heptapteridae were obtained. A cluster analysis revealed the presence of three trophic guilds (detritivores, insectivores and omnivores). Principal components analysis demonstrated the segregation of two ecomorphotypes: at one extreme there were the detritivores (Loricariidae) with morphological structures that are fundamental in allowing them to fix themselves to substrates characterised by rushing torrents, thus permitting them to graze on the detritus and organic materials encrusted on the substrate; at the other extreme of the gradient there were the insectivores and omnivores (Heptapteridae), with morphological characteristics that promote superior performance in the exploitation of structurally complex habitats with low current velocity, colonised by insects and plants. Canonical discriminant analysis revealed an ecomorphological divergence between insectivores, which have morphological structures that permit them to capture prey in small spaces among rocks, and omnivores, which have a more compressed body and tend to explore food items deposited in marginal backwater zones. Mantel tests showed that trophic structure was significantly related to the body shape of a species, independently of the phylogenetic history, indicating that, in this case, there was an ecomorphotype for each trophic guild. Therefore, the present study demonstrated that the Siluriformes of the Caracu Stream were ecomorphologically structured and that morphology can be applied as an additional tool in predicting the trophic structure of this group.

  20. A chromosomal analysis of Nepa cinerea Linnaeus, 1758 and Ranatra linearis (Linnaeus, 1758) (Heteroptera, Nepidae)

    PubMed Central

    Angus, Robert B.; Jeangirard, Constance; Stoianova, Desislava; Grozeva, Snejana; Kuznetsova, Valentina G.

    2017-01-01

    Abstract An account is given of the karyotypes and male meiosis of the Water Scorpion Nepa cinerea Linnaeus, 1758 and the Water Stick Insect Ranatra linearis (Linnaeus, 1758) (Heteroptera, Nepomorpha, Nepidae). A number of different approaches and techniques were tried: the employment of both male and female gonads and mid-guts as the sources of chromosomes, squash and air-drying methods for chromosome preparations, C-banding and fluorescence in situ hybridization (FISH) for chromosome study. We found that N. cinerea had a karyotype comprising 14 pairs of autosomes and a multiple sex chromosome system, which is X1X2X3X4Y (♂) / X1X1X2X2X3X3X4X4 (♀), whereas R. linearis had a karyotype comprising 19 pairs of autosomes and a multiple sex chromosome system X1X2X3X4Y (♂) / X1X1X2X2X3X3X4X4 (♀). In both N. cinerea and R. linearis, the autosomes formed chiasmate bivalents in spermatogenesis, and the sex chromosome univalents divided during the first meiotic division and segregated during the second one suggesting thus a post-reductional type of behaviour. These results confirm and amplify those of Steopoe (1925, 1927, 1931, 1932) but are inconsistent with those of other researchers. C-banding appeared helpful in pairing up the autosomes for karyotype assembly; however in R. linearis the chromosomes were much more uniform in size and general appearance than in N. cinerea. FISH for 18S ribosomal DNA (major rDNA) revealed hybridization signals on two of the five sex chromosomes in N. cinerea. In R. linearis, rDNA location was less obvious than in N. cinerea; however it is suggested to be similar. We have detected the presence of the canonical “insect” (TTAGG)n telomeric repeat in chromosomes of these species. This is the first application of C-banding and FISH in the family Nepidae. PMID:29114353

  1. Regional and temporal changes in epizoobiontic bryozoan-communities of Flustra foliacea (Linnaeus, 1758) and implications for North Sea ecology

    NASA Astrophysics Data System (ADS)

    Bitschofsky, F.; Forster, S.; Scholz, J.

    2011-02-01

    Until recently, bryozoans have not been used as indicators for changes in bottom communities or climate control in the North Sea Basin, despite a 200-year history of bryozoan collecting. The epizoobiontic bryozoan fauna of Flustra foliacea (Linnaeus, 1758) was analysed on 51 sample stations kept in four German museums. The samples cover the entire North Sea and different time periods (1776-2008, mainly the period of 1904/1905 compared to 1980-87). Cluster analysis shows a differentiation into a northern and a southern North Sea assemblage. The northern assemblage is characterized by Amphiblestrum flemingii (Busk, 1854), Callopora dumerilii (Audouin, 1826) and Tricellaria ternata (Ellis & Solander, 1786), while the southern North Sea is characterized by Electra pilosa (Linnaeus, 1767), Crisia eburnea (Linnaeus, 1758) and Plagioecia patina (Lamarck, 1816). Spatial separation approximately follows the 50 m depth contour. The temporal distribution patterns of bryozoans are discussed in terms of NAO (North Atlantic Oscillation) and temperature variations.

  2. Dynamic characteristics of motor-gear system under load saltations and voltage transients

    NASA Astrophysics Data System (ADS)

    Bai, Wenyu; Qin, Datong; Wang, Yawen; Lim, Teik C.

    2018-02-01

    In this paper, a dynamic model of a motor-gear system is proposed. The model combines a nonlinear permeance network model (PNM) of a squirrel-cage induction motor and a coupled lateral-torsional dynamic model of a planetary geared rotor system. The external excitations including voltage transients and load saltations, as well as the internal excitations such as spatial effects, magnetic circuits topology and material nonlinearity in the motor, and time-varying mesh stiffness and damping in the planetary gear system are considered in the proposed model. Then, the simulation results are compared with those predicted by the electromechanical model containing a dynamic motor model with constant inductances. The comparison showed that the electromechanical system model with the PNM motor model yields more reasonable results than the electromechanical system model with the lumped-parameter electric machine. It is observed that electromechanical coupling effect can induce additional and severe gear vibrations. In addition, the external conditions, especially the voltage transients, will dramatically affect the dynamic characteristics of the electromechanical system. Finally, some suggestions are offered based on this analysis for improving the performance and reliability of the electromechanical system.

  3. Occurrence of the Leech, Pontobdella muricata Linnaeus, on Elasmobranch Species in the Northern and Central Adriatic Sea.

    PubMed

    Bolognini, Luca; Leoni, Simone; Polidori, Piero; Grati, Fabio; Scarcella, Giuseppe; Pellini, Giulio; Domenichetti, Filippo; Ferrà, Carmen; Fabi, Gianna

    2016-12-01

    This study provides a parasitological analysis of the elasmobranch species caught in the northern and central Adriatic Sea. Sixty-two marine leeches were recorded on 747 individuals of Raja clavata Linnaeus, 1758 (thornback ray), Myliobatis aquila Linnaeus, 1758 (common eagle ray), and Torpedo marmorata Risso, 1810 (marbled torpedo ray) caught in 56 hauls over a 5 yr period. All leeches were identified as Pontobdella muricata, which is a typical ectoparasite of benthic elasmobranchs. The prevalence of infection ranged from 7.11% on R. clavata to 12.00% on M. aquila. The intensity of infection, the preferential sites of attachment to the host, and the periodicity of infection were evaluated.

  4. The effect of wet-dry weathering on the rate of bedrock river channel erosion by saltating gravel

    USGS Publications Warehouse

    Inoue, Takuya; Yamaguchi, Satomi; Nelson, Jonathan M.

    2017-01-01

    Previous work has shown that the bedrock erosion rate E because of collisions of saltating bedload can be expressed by E = βqb(1-Pc), where qb is the sediment transport rate, Pc is the extent of alluvial cover, and β is the abrasion coefficient. However, the dependence of the abrasion coefficient on the physical characteristics of the bedrock material is poorly known, and in particular, the effects of wet-dry weathering on the saltation-abrasion bedrock incision has not been specifically characterized. Observation suggests that the typical wet-dry cycling of exposed bedrock in river beds gives rise to cracks and voids that are likely to alter the incision rate of the material when subjected to impacts of moving sediment. In this study, flume experiments are performed to develop an understanding of how wet-dry cycling affects the rock tensile strength and the bedrock erosion rate. To represent the physical effects of weathering, boring cores taken from natural bedrock channel are exposed to artificial wet-dry cycles. The experimental results suggest the following: (1) the abrasion coefficient for fresh bedrock is estimated by β = 1.0 × 10− 4σT− 2(d/ksb)0.5, where σT is the tensile strength, d is the diameter of colliding gravel, and ksb is the hydraulic roughness height of bedrock; (2) the tensile strength of the bedrock decreases exponentially as a result of repeated wet-dry cycles, σT/σT0 = exp (-CTNWa0/σT0), where σT0 is the initial tensile strength, Wa0 is the initial normalized rate of water absorption., N is the number of wet-dry cycles, and CT is a constant; (3) the erosion rate of fresh bedrock depends on the inverse of the square of tensile strength, but the erosion rate of weathered bedrock depends on the − 1.5 power of tensile strength.

  5. Ichthyouris voltagrandensis n.sp. (Nematoda: Pharyngodonidae) from Myleus tiete Eigenmann & Norris, 1900 (Osteichthyes: Characidae) in the Volta Grande Reservoir, MG, Brazil.

    PubMed

    Martins, M L; Yoshitoshi, E R; Umekita, H

    2001-05-01

    The present work studied helminth parasites of "pacu-manteiga", Myleus tiete (Osteichthyes: Characidae) from Volta Grande Reservoir, MG, Brazil. Fishes with 142.6 +/- 24.7 g weight and 17.3 +/- 1.0 cm total length were collected. Five out six analysed fish (prevalence 83.3%) were parasitized in the intestine with an average of 535.6 +/- 334.6 oxyurid nematodes per fish. The helminth was identified as Ichthyouris voltagrandensis n.sp. (Nematoda: Pharyngodonidae). It differs from I. brasiliensis (Moravec et al., 1992a) by the absence of lateral alae, higher measures of tail and caudal alae of males, esophageal isthmus length, distance of excretory pore from anterior end and spicule length. In addition, eggs were provided by two long filaments in just one pole and by the first time the authors observed flagellate spermatozoa from dissected males. The authors exposes comparative table of measures of the five described species of the genus Ichthyouris.

  6. Two new gonad-infecting species of Philometra Costa, 1845 (Nematoda: Philometridae) from Trachinus spp. (Osteichthyes: Trachinidae) in the Gulf of Hammamet, Tunisia.

    PubMed

    Ghanmi, Nessrine; González-Solís, David; Gargouri, Lamia

    2018-03-01

    Based on light and scanning electron microscopical studies, two new gonad-infecting species of Philometra Costa, 1845, P. draco n. sp. and P. radiata n. sp. (Nematoda: Philometridae), are described from the marine perciform fishes Trachinus draco (Linnaeus) and T. radiatus (Linnaeus) (both Trachinidae), respectively, in the Gulf of Hammamet, off the northeastern coast of Tunisia. Philometra draco n. sp. and P. radiata n. sp. can be separated from other gonad-infecting species of this genus by the structures associated to the gubernaculum (e.g. dorsal protuberance, smooth field separating the dorsolateral longitudinal parts), as well as by the length of the body, spicules and gubernaculum. Philometra radiata n. sp. can be distinguished from P. draco n. sp. in having the dorsal side of the gubernaculum distal end provided with a median longitudinal smooth field demarcated by two dorsolateral lamellate parts. These two new species are the first philometrid species described from fishes of the family Trachinidae.

  7. Seawater Ca2+ concentration influences solar orientation in Talitrus saltator (Crustacea, Amphipoda).

    PubMed

    Ugolini, Alberto; Ungherese, Giuseppe; Mercatelli, Luca; Saer, Doumett; Lepri, Luciano

    2009-03-01

    The role of salinity in the ecophysiology of many intertidal invertebrates has been extensively investigated. Calcium (Ca(2+)), magnesium (Mg(2+)), potassium (K(+)) and sodium (Na(+)) are the major constituents of seawater and it has been demonstrated that sandhoppers tested under the sun in diluted seawater (3.5 per thousand) head seaward, instead of going landward as expected. Therefore, the variation in seawater salinity (from 35 per thousand to 3.5 per thousand) influences their directional choice. This paper investigates the contribution of different cations to the sea-land directional choice of Talitrus saltator (Crustacea, Amphipoda) by the sun compass orientation mechanism. Results of releases carried out in basic seawater selectively deprived of Ca(2+), Mg(2+) or K(+) and containing the same concentration of Na(+) indicate that only the reduction in Ca(2+) concentration affects the capacity of solar orientation. The pH does not influence the directional choice of sandhoppers and nor do small variations in salinity in the range 32-39 per thousand. Moreover, the clear photopositive tendency registered in experiments of phototaxis in Ca(2+)-deprived seawater indicates that the absence of Ca(2+) does not affect the normal functioning of the visual cells. Therefore, our results show that Ca(2+) seawater concentration is important for the correct functioning of one of the principal mechanisms of orientation in supralittoral amphipods and it could affect their survival in the field.

  8. Carl Linnaeus, Erasmus Darwin and Anna Seward: Botanical Poetry and Female Education

    NASA Astrophysics Data System (ADS)

    George, Sam

    2014-03-01

    This article will explore the intersection between `literature' and `science' in one key area, the botanical poem with scientific notes. It reveals significant aspects of the way knowledge was gendered in the Enlightenment, which is relevant to the present-day education of girls in science. It aims to illustrate how members of the Lichfield Botanical Society (headed by Erasmus Darwin) became implicated in debates around the education of women in Linnaean botany. The Society's translations from Linnaeus inspired a new genre of women's educational writing, the botanical poem with scientific notes, which emerged at this time. It focuses in particular on a poem by Anna Seward and argues that significant problems regarding the representation of the Linnaean sexual system of botany are found in such works and that women in the culture of botany struggled to give voice to a subject which was judged improper for female education. The story of this unique poem and the surrounding controversies can teach us much about how gender impacted upon women's scientific writing in eighteenth century Britain, and how it shaped the language and terminology of botany in works for female education. In particular, it demonstrates how the sexuality of plants uncovered by Linnaeus is a paradigmatic illustration of how societal forces can simultaneously both constrict and stimulate women's involvement in science. Despite the vast changes to women's access in scientific knowledge of the present day, this `fair sexing' of botany illustrates the struggle that women have undergone to give voice to their botanical knowledge.

  9. Refinement of the karyological aspects of Psidium guineense (Swartz, 1788): a comparison with Psidium guajava (Linnaeus, 1753)

    PubMed Central

    Marques, Anelise Machado; Tuler, Amélia Carlos; Carvalho, Carlos Roberto; Carrijo, Tatiana Tavares; Ferreira, Marcia Flores da Silva; Clarindo, Wellington Ronildo

    2016-01-01

    Abstract Euploidy plays an important role in the evolution and diversification of Psidium Linnaeus, 1753. However, few data about the nuclear DNA content, chromosome characterization (morphometry and class) and molecular markers have been reported for this genus. In this context, the present study aims to shed light on the genome of Psidium guineense Swartz, 1788, comparing it with Psidium guajava Linnaeus, 1753. Using flow cytometry, the nuclear 2C value of Psidium guineense was 2C = 1.85 picograms (pg), and the karyotype showed 2n = 4x = 44 chromosomes. Thus, Psidium guineense has four chromosome sets, in accordance with the basic chromosome number of Psidium (x = 11). In addition, karyomorphometric analysis revealed morphologically identical chromosome groups in the karyotype of Psidium guineense. The high transferability of microsatellites (98.6%) further corroborates with phylogenetic relationship between Psidium guajava and Psidium guineense. Based on the data regarding nuclear genome size, karyotype morphometry and molecular markers of Psidium guineense and Psidium guajava (2C = 0.95 pg, 2n = 2x = 22 chromosomes), Psidium guineense is a tetraploid species. These data reveal the role of euploidy in the diversification of the genus Psidium. PMID:27186342

  10. Genome-wide and caste-specific DNA methylomes of the ants Camponotus floridanus and Harpegnathos saltator

    PubMed Central

    Bonasio, Roberto; Li, Qiye; Lian, Jinmin; Mutti, Navdeep S.; Jin, Lijun; Zhao, Hongmei; Zhang, Pei; Wen, Ping; Xiang, Hui; Ding, Yun; Jin, Zonghui; Shen, Steven S.; Wang, Zongji; Wang, Wen; Wang, Jun; Berger, Shelley L.; Liebig, Jürgen; Zhang, Guojie; Reinberg, Danny

    2012-01-01

    SUMMARY Background Ant societies comprise individuals belonging to different castes characterized by specialized morphologies and behaviors. Because ant embryos can follow different developmental trajectories, epigenetic mechanisms must play a role in caste determination. Ants have a full set of DNA methyltransferase and their genomes contain methylcytosine. To determine the relationship between DNA methylation and phenotypic plasticity in ants, we obtained and compared the genome-wide methylomes of different castes and developmental stages of Camponotus floridanus and Harpegnathos saltator. Results In the ant genomes, methylcytosines are found both in CpG and non-CpG contexts and are strongly enriched at exons of active genes. Changes in exonic DNA methylation correlate with alternative splicing events such as exon skipping and alternative splice site selection. Several genes exhibit caste-specific and developmental changes in DNA methylation that are conserved between the two species, including genes involved in reproduction, telomere maintenance, and noncoding RNA metabolism. Several loci are methylated and expressed monoallelically, and in some cases the choice of methylated allele depends on the caste. Conclusions These first ant methylomes and their intra- and inter-species comparison reveal an exonic methylation pattern that points to a connection between DNA methylation and splicing. The presence of monoallelic DNA methylation and the methylation of non-CpG sites in all samples suggest roles in genome regulation in these social insects, including the intriguing possibility of parental or caste-specific genomic imprinting. PMID:22885060

  11. Analysis of the blackening of green pepper (Piper nigrum Linnaeus) berries.

    PubMed

    Gu, Fenglin; Tan, Lehe; Wu, Huasong; Fang, Yiming; Wang, Qinghuang

    2013-06-01

    This paper investigates polyphenol oxidase (PPO) activity, reduced weight percentage after sun drying, and the changes in colour and appearance of green pepper (Piper nigrum Linnaeus) berries after blanching and sun drying. The results show that the degree of reduced weight percentage and browning in green pepper berries after blanching for 10 min is greater at 100°C than at 90 and 80°C. Moreover, the samples blanched at 100°C for 10 min had the fastest water loss, but the lowest PPO activity. Thus, the PPO enzymatic oxidation of polyphenols might not be the only reason for the browning of green pepper berries. This result is significantly different from that of Variyar, Pendharkar, Banerjeea, and Bandyopadhyay (1988) and therefore deserves further study. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Behaviour of Talitrus saltator (Crustacea: Amphipoda) on a rehabilitated sandy beach on the European Atlantic Coast (Portugal)

    NASA Astrophysics Data System (ADS)

    Bessa, Filipa; Rossano, Claudia; Nourisson, Delphine; Gambineri, Simone; Marques, João Carlos; Scapini, Felicita

    2013-01-01

    Environmental and human controls are widely accepted as the main structuring forces of the macrofauna communities on sandy beaches. A population of the talitrid amphipod Talitrus saltator (Montagu, 1808) was investigated on an exposed sandy beach on the Atlantic coast of Portugal (Leirosa beach) to estimate orientation capabilities and endogenous rhythms in conditions of recent changes in the landscape (artificial reconstruction of the foredune) and beach morphodynamics (stabilization against erosion from the sea). We tested sun orientation of talitrids on the beach and recorded their locomotor activity rhythms under constant conditions in the laboratory. The orientation data were analysed with circular statistics and multiple regression models adapted to angular distributions, to highlight the main factors and variables influencing the variation of orientation. The talitrids used the sun compass, visual cues (landscape and sun visibility) to orient and the precision of orientation varied according to the tidal regime (rising or ebbing tides). A well-defined free-running rhythm (circadian with in addition a bimodal rhythmicity, likely tidal) was highlighted in this population. This showed a stable behavioural adaptation on a beach that has experienced a process of artificial stabilization of the dune through nourishment actions over a decade. Monitoring the conditions of such dynamic environments and the resilience capacity of the inhabiting macroinfauna is a main challenge for sandy beach ecologists.

  13. First report of natural infection of least weasel (Mustela nivalis Linnaeus, 1776) with Leishmania major in Tunisia.

    PubMed

    Ghawar, Wissem; Snoussi, Mohamed Ali; Hamida, Nabil Bel Haj; Boukthir, Aïcha; Yazidi, Rihab; Chaâbane, Sana; Chemkhi, Jomâa; Zâatour, Amor; Salah, Afif Ben

    2011-11-01

    Zoonotic cutaneous leishmaniasis, caused by Leishmania major (L. major), is endemic in Tunisia. Several rodents have been identified as reservoir hosts of parasites. This study reports, for the first time, the natural infection with L. major zymodeme MON-25 in a specimen of least weasel: Mustela nivalis Linnaeus, 1776 (M. nivalis) collected in Sidi Bouzid. This finding justifies further research on larger samples of this animal to verify its role as a potential reservoir host for cutaneous leishmaniasis in Tunisia.

  14. Orchid biology: from Linnaeus via Darwin to the 21st century

    PubMed Central

    Fay, Michael F.; Chase, Mark W.

    2009-01-01

    Orchidaceae are the largest family of flowering plants, with at least 24 000 species, and perhaps better than any other family of flowering plants, orchids represent the extreme specializations that are possible. As a result, they have long fascinated luminaries of the botanical world including Linnaeus and Darwin, but the size of the family has historically been an impediment to their study. Specifically, the lack of detailed information about relationships within the family made it difficult to formulate explicit evolutionary hypotheses for such a large group, but the advent of molecular systematics has revolutionized our understanding of the orchids. Their complex life histories make orchids particularly vulnerable to environmental change, and as result many are now threatened with extinction. In this Special Issue we present a series of 20 papers on orchid biology ranging from phylogenetics, floral evolutionary development, taxonomy, mycorrhizal associations, pollination biology, population genetics and conservation. PMID:19654223

  15. Epidemiological and molecular data on heterophyid trematode metacercariae found in the muscle of grey mullets (Osteichthyes: Mugilidae) from Sardinia (western Mediterranean Sea).

    PubMed

    Masala, Simonetta; Piras, Maria Cristina; Sanna, Daria; Chai, Jong-Yil; Jung, Bong-Kwang; Sohn, Woon-Mok; Garippa, Giovanni; Merella, Paolo

    2016-09-01

    This study is a contribution to the molecular taxonomy and epidemiology of heterophyid (Trematoda: Heterophyidae) metacercariae found in the muscle of Mugilidae (Osteichthyes) from Sardinia (western Mediterranean Sea). Sixty specimens of mugilids (13 Chelon labrosus, 18 Liza aurata, 6 Liza ramada, 8 Liza saliens, 15 Mugil cephalus) were examined and 17,899 metacercariae isolated in 95 % of the hosts. Four types of metacercariae were identified: Heterophyes sp. (n = 14,113), Heterophyes sp. -small (1225), Stictodora sp. (1606), and Ascocotyle (Phagicola) sp. (955). The experimental infection of a hamster with Heterophyes sp. metacercariae produced six adults identified as Heterophyes heterophyes and two as Heterophyes cf. nocens. The morphology of Heterophyes sp. -small metacercariae matched with that of Heterophyes dispar. The sequence analysis of the ITS2 and 28S portions of rDNA confirmed the morphological identification of metacercariae, showing four clusters. All adults grouped together with the Heterophyes sp. metacercariae, whereas adults of Heterophyes nocens from Korea clustered separately, showing that this species is distinguished from H. heterophyes, and suggesting caution in the exclusive use of the number of rodlets of the genital sucker to separate the two species. The presence of metacercariae was high in all hosts; the highest prevalence is of Heterophyes sp. (prevalence ≥78 %; mean intensity ≥135 metacercariae/100 g muscle), and the most heavily infected host is M. cephalus (prevalence = 100 %; mean intensity = 841 metacercariae/100 g muscle).

  16. Larva and pupa of Megatoma (s. str.) undata (Linnaeus, 1758) with remarks on biology and economic importance (Coleoptera, Dermestidae).

    PubMed

    Kadej, Marcin

    2017-01-01

    An updated description of the final larval instar and pupa of Megatoma (s. str.) undata (Linnaeus, 1758) (Coleoptera: Dermestidae) is presented. Several morphological characteristics of M. undata larvae are documented and discussed: antenna, epipharynx, mandibula, maxilla, ligula with labial palpi, hastisetae, terga, and condition of the antecostal suture. The paper is fully illustrated and includes some important additions to extend notes on this species available in the references. Summarised data about biology, economic importance, and distribution of M. undata are also provided.

  17. Larva and pupa of Megatoma (s. str.) undata (Linnaeus, 1758) with remarks on biology and economic importance (Coleoptera, Dermestidae)

    PubMed Central

    Kadej, Marcin

    2017-01-01

    Abstract An updated description of the final larval instar and pupa of Megatoma (s. str.) undata (Linnaeus, 1758) (Coleoptera: Dermestidae) is presented. Several morphological characteristics of M. undata larvae are documented and discussed: antenna, epipharynx, mandibula, maxilla, ligula with labial palpi, hastisetae, terga, and condition of the antecostal suture. The paper is fully illustrated and includes some important additions to extend notes on this species available in the references. Summarised data about biology, economic importance, and distribution of M. undata are also provided. PMID:29134022

  18. Aeolian snow transport from wind tunnel experiments

    NASA Astrophysics Data System (ADS)

    Paterna, E.; Crivelli, P.; Lehning, M.

    2016-12-01

    Aeolian snow transport has a significant impact on snow redistribution in mountains, prairies as well as on glaciers, ice shelves, and sea ice. In all these environments, the local mass balance is highly influenced by Aeolian snow transport. The dynamics of snow saltation has a high impact on the land surface processes shaping these regions. More specifically, the observed high intermittency of saltation fluxes poses a problem for saltation models and needs to be better understood. We therefore aimed at unveiling the mechanisms underlying snow saltation at different saltation strengths and its coupling with the turbulent fluctuations of the wind. We conducted wind tunnel measurements of the momentum and mass-fluxes during snow saltation. For the mass-flux measurements we employed a shadowgraphy system which acquires images of the snow particle's shadows at high spatial and temporal resolution. The size and displacement of the particles are then determined by means of image analysis and Particle Tracking Velocimetry (PTV), allowing to estimate both snow mass-flux and flow velocity. Our controlled wind tunnel experiments revealed the existence of two regimes of saltation. In a turbulence-dependent regime occurring during weak saltation activity, we observed a strong coupling between snow transport and turbulent flow. Conversely during stronger saltation activity a turbulence-independent regime emerges, where the saltation develops its own length scale and it efficiently decouples from the wind fluctuations. We argue that different entrainment mechanisms could explain the existence of the two different saltation regimes as well as the observed high level of mass-flux intermittency.

  19. The discovery of Caligus temnodontis Brian, 1924 (Copepoda: Caligidae) from the bluefish Pomatomus saltatrix (Linnaeus) in the eastern Mediterranean Sea.

    PubMed

    Ozak, Argun A; El-Rashidy, Hoda H; Demirkale, Ibrahim; Boxshall, Geoff A

    2010-07-01

    The temnodontis variety of Caligus mauritanicus Brian, 1924 described by Brian (1924) is a valid species known only from a single host species, Pomatomus saltatrix (Linnaeus). New material of this species has been examined from the same host fish caught from Abuqir Bay, Alexandria (Egypt), from Iskenderun Bay (Turkey) and from off the coast of South Africa. Using this material, C. temnodontis Brian, 1924 is redescribed and compared with related species. It is most closely related to the Indo-Pacific species C. pagrosomi Yamaguti, 1939.

  20. First report of the genus Tettigonia Linnaeus (Orthoptera: Tettigoniidae: Tettigoniinae) and record of Tettigonia caudata caudata (Charpentier, 1842) from India.

    PubMed

    Nagar, Rajendra; Swaminathan, R

    2017-04-28

    The genus Tettigonia Linnaeus (Tettigoniidae; Tettigoniinae) with the type species, Gryllus (Tettigonia) viridissima Linnaeus, 1758 belongs to the tribe Tettigoniini, which is represented by 15 genera and 27 species worldwide (Cigliano et al., 2017). According to the annotated checklist, the subfamily Tettigoniinae includes the only tribe Platycleidini Brunner von Wattenwyl, 1893 with 2 genera and 3 species as reported from India by Shishodia et al. (2010). In a review of Orthoptera from the Eastern Palearctic region, the genus Tettigonia Linnaeus was reported by Storozhenko (1994); additionally, some new species of Tettigonia have been described by Ogawa (2003), Greenwalt and Rust (2014), Chobanov et al. (2014), Sultan et al. (2015) and Storozhenko et al. (2015). The sub-family Tettigoniinae is represented by many species endemic to the Asian part of the Palearctic region. In 1971, Kaltenbach studied the Decticinae of the Palearctic, a subfamily now considered part of Tettigoniinae, comprising 65 genera with 407 species; later, Rentz and Colless (1990) estimated 500 species for Tettigoniinae. Further, Rentz (1985) clarified that these species do not occur in tropical rainforests, but are found in grassland and mixed heath habitats. The shape of pronotum, with a distinct angulated shoulder incision, with the clarities and locations of its transversal sulci, and its short, compressed and depressed structure happens to be a common character for the members of the tribe Tettigoniini. The type genus Tettigonia is long winged; however, considerable variability in the wing length has been reported. Nevertheless, the short tegmina reaching to the end of hind knee is a character often used to separate T. caudata and T. viridissima from T. cantans and T. hispina (Haz, 1969).

  1. Wind sorting affects differently the organo-mineral composition of saltating and particulate materials in contrasting texture agricultural soils

    NASA Astrophysics Data System (ADS)

    Iturri, Laura Antonela; Funk, Roger; Leue, Martin; Sommer, Michael; Buschiazzo, Daniel Eduardo

    2017-10-01

    There is little information about the mineral and organic composition of sediments eroded by wind at different heights. Because of that, wind tunnel simulations were performed on four agricultural loess soils of different granulometry and their saltating materials collected at different heights. The particulate matter with an aerodynamic diameter mainly smaller than 10 μm (PM10) of these soils was obtained separately by a laboratory method. Results indicated that the granulometric composition of sediments collected at different heights was more homogeneous in fine- than in sandy-textured soils, which were more affected by sorting effects during wind erosion. This agrees with the preferential transport of quartz at low heights and of clay minerals at greater heights. SOC contents increased with height, but the composition of the organic materials was different: stable carboxylic acids, aldehydes, amides and aromatics were preferentially transported close to the ground because their were found in larger aggregates, while plant debris and polysaccharides, carbohydrates and derivatives of microbial origin from organic matter dominated at greater heights for all soil types. The amount of SOC in the PM10 fraction was higher when it was emitted from sandy than from fine textured soils. Because of the sorting process produced by wind erosion, the stable organic matter compounds will be transported at low heights and local scales, modifying soil fertility due to nutrient exportation, while less stable organic compounds will be part of the suspension losses, which are known to affect some processes at regional- or global scale.

  2. Redescription of immature stages of central European fireflies, Part 1: Lampyris noctiluca (Linnaeus, 1758) larva, pupa and notes on its biology (Coleoptera: Lampyridae: Lampyrinae).

    PubMed

    Novák, Martin

    2017-03-28

    The mature larva of Lampyris noctiluca (Linnaeus, 1758) is redescribed and illustrated in detail, including scanning electron microscope images. Male and female pupae are briefly described, including notes on behaviour as well as light production of the immature stages. Observed structures, life cycle and behaviour of larvae and pupae are discussed.

  3. Impact of elevated levels of atmospheric CO2 and herbivory on flavonoids of soybean (Glycine max Linnaeus).

    PubMed

    O'Neill, Bridget F; Zangerl, Arthur R; Dermody, Orla; Bilgin, Damla D; Casteel, Clare L; Zavala, Jorge A; DeLucia, Evan H; Berenbaum, May R

    2010-01-01

    Atmospheric levels of carbon dioxide (CO2) have been increasing steadily over the last century. Plants grown under elevated CO2 conditions experience physiological changes, particularly in phytochemical content, that can influence their suitability as food for insects. Flavonoids are important plant defense compounds and antioxidants that can have a large effect on leaf palatability and herbivore longevity. In this study, flavonoid content was examined in foliage of soybean (Glycine max Linnaeus) grown under ambient and elevated levels of CO2 and subjected to damage by herbivores in three feeding guilds: leaf skeletonizer (Popillia japonica Newman), leaf chewer (Vanessa cardui Linnaeus), and phloem feeder (Aphis glycines Matsumura). Flavonoid content also was examined in foliage of soybean grown under ambient and elevated levels of O3 and subjected to damage by the leaf skeletonizer P. japonica. The presence of the isoflavones genistein and daidzein and the flavonols quercetin and kaempferol was confirmed in all plants examined, as were their glycosides. All compounds significantly increased in concentration as the growing season progressed. Concentrations of quercetin glycosides were higher in plants grown under elevated levels of CO2. The majority of compounds in foliage were induced in response to leaf skeletonization damage but remained unchanged in response to non-skeletonizing feeding or phloem-feeding. Most compounds increased in concentration in plants grown under elevated levels of O3. Insects feeding on G. max foliage growing under elevated levels of CO2 may derive additional antioxidant benefits from their host plants as a consequence of the change in ratios of flavonoid classes. This nutritional benefit could lead to increased herbivore longevity and increased damage to soybean (and perhaps other crop plants) in the future.

  4. Molecular studies with Aedes (Stegomyia) aegypti (Linnaeus, 1762), mosquito transmitting the dengue virus.

    PubMed

    Pereira, Luciana Patrícia Lima Alves; Brito, Maria Cristiane Aranha; Araruna, Felipe Bastos; de Andrade, Marcelo Souza; Moraes, Denise Fernandes Coutinho; Borges, Antônio Carlos Romão; do Rêgo Barros Pires Leal, Emygdia Rosa

    2017-08-01

    Dengue is an infectious viral disease, which can present a wide clinical picture, ranging from oligo or asymptomatic forms, to bleeding and shock, and can progress to death. The disease problem has increased in recent years, especially in urban and suburban areas of tropical and subtropical regions. There are five dengue viruses, called serotypes (DEN-1, DEN-2, DEN-3, DEN-4, and DEN-5), which belong to the Flaviviridae family and are transmitted to humans through infected mosquito bites, with the main vector the Aedes aegypti mosquito (Linnaeus, 1762). Studies performed with Ae. aegypti, aimed at their identification and analysis of their population structure, are fundamental to improve understanding of the epidemiology of dengue, as well for the definition of strategic actions that reduce the transmission of this disease. Therefore, considering the importance of such research to the development of programs to combat dengue, the present review considers the techniques used for the molecular identification, and evaluation of the genetic variability of Ae. aegypti.

  5. Structural and Immunological Activity Characterization of a Polysaccharide Isolated from Meretrix meretrix Linnaeus

    PubMed Central

    Li, Li; Li, Heng; Qian, Jianying; He, Yongfeng; Zheng, Jialin; Lu, Zhenming; Xu, Zhenghong; Shi, Jinsong

    2015-01-01

    Polysaccharides from marine clams perform various biological activities, whereas information on structure is scarce. Here, a water-soluble polysaccharide MMPX-B2 was isolated from Meretrix meretrix Linnaeus. The proposed structure was deduced through characterization and its immunological activity was investigated. MMPX-B2 consisted of d-glucose and d-galctose residues at a molar ratio of 3.51:1.00. The average molecular weight of MMPX-B2 was 510 kDa. This polysaccharide possessed a main chain of (1→4)-linked-α-d-glucopyranosyl residues, partially substituted at the C-6 position by a few terminal β-d-galactose residues or branched chains consisting of (1→3)-linked β-d-galactose residues. Preliminary immunological tests in vitro showed that MMPX-B2 could stimulate the murine macrophages to release various cytokines, and the structure-activity relationship was then established. The present study demonstrated the potential immunological activity of MMPX-B2, and provided references for studying the active ingredients in M. meretrix. PMID:26729136

  6. Metabolic plasticity of nitrogen assimilation by Porphyra umbilicalis (Linnaeus) Kützing

    NASA Astrophysics Data System (ADS)

    Kim, Jang K.; Kraemer, George P.; Yarish, Charles

    2012-12-01

    The physical stresses associated with emersion have long been considered major factors determining the vertical zonation of intertidal seaweeds. We examined Porphyra umbilicalis (Linnaeus) Kützing thalli from the vertical extremes in elevation of an intertidal population ( i.e. upper and lower intertidal zones) to determine whether Porphyra thalli acclimate to different vertical elevations on the shore with different patterns of nitrate uptake and nitrate reductase (NR) and glutamine synthetase (GS) activities in response to different degrees of emersion stress. We found that the nitrate uptake and NR recovery in the emersed tissues took longer in lower intertidal sub-population than in upper intertidal sub-population; and GS activity was also significantly affected by emersion and, interestingly, such an activity was enhanced by emersion of thalli from both upper and lower intertidal zones. These results suggested that intra-population variability in post-emersion recovery of physiological functions such as nutrient uptake and NR activity enables local adaptation and contributes to the wide vertical distribution of P. umbilicalis. The high GS activity during periodic emersion stress may be a protective mechanism enabling P. umbilicalis to assimilate nitrogen quickly when it again becomes available, and may also be an evidence of photorespiration during emersion.

  7. Microsatellite loci discovery from next-generation sequencing data and loci characterization in the epizoic barnacle Chelonibia testudinaria (Linnaeus, 1758)

    PubMed Central

    Zardus, John D.; Wares, John P.

    2016-01-01

    Microsatellite markers remain an important tool for ecological and evolutionary research, but are unavailable for many non-model organisms. One such organism with rare ecological and evolutionary features is the epizoic barnacle Chelonibia testudinaria (Linnaeus, 1758). Chelonibia testudinaria appears to be a host generalist, and has an unusual sexual system, androdioecy. Genetic studies on host specificity and mating behavior are impeded by the lack of fine-scale, highly variable markers, such as microsatellite markers. In the present study, we discovered thousands of new microsatellite loci from next-generation sequencing data, and characterized 12 loci thoroughly. We conclude that 11 of these loci will be useful markers in future ecological and evolutionary studies on C. testudinaria. PMID:27231653

  8. Homage to Linnaeus: How many parasites? How many hosts?

    USGS Publications Warehouse

    Dobson, Andy; Lafferty, Kevin D.; Kuris, Armand M.; Hechinger, Ryan F.; Jetz, Walter

    2008-01-01

    Estimates of the total number of species that inhabit the Earth have increased significantly since Linnaeus's initial catalog of 20,000 species. The best recent estimates suggest that there are ≈6 million species. More emphasis has been placed on counts of free-living species than on parasitic species. We rectify this by quantifying the numbers and proportion of parasitic species. We estimate that there are between 75,000 and 300,000 helminth species parasitizing the vertebrates. We have no credible way of estimating how many parasitic protozoa, fungi, bacteria, and viruses exist. We estimate that between 3% and 5% of parasitic helminths are threatened with extinction in the next 50 to 100 years. Because patterns of parasite diversity do not clearly map onto patterns of host diversity, we can make very little prediction about geographical patterns of threat to parasites. If the threats reflect those experienced by avian hosts, then we expect climate change to be a major threat to the relatively small proportion of parasite diversity that lives in the polar and temperate regions, whereas habitat destruction will be the major threat to tropical parasite diversity. Recent studies of food webs suggest that ≈75% of the links in food webs involve a parasitic species; these links are vital for regulation of host abundance and potentially for reducing the impact of toxic pollutants. This implies that parasite extinctions may have unforeseen costs that impact the health and abundance of a large number of free-living species.

  9. Regional assessment of PAHs contamination in SE Brazil using brown mussels (Perna perna Linnaeus 1758).

    PubMed

    Yoshimine, Renato V; Carreira, Renato S; Scofield, Arthur L; Wagener, Angela L R

    2012-11-01

    Cultured and native brown mussels (Perna perna Linnaeus 1758) were used to evaluate the contamination by PAHs in the SE Brazilian coastal zone. Mean concentrations of total PAH (38 parental and alkylated compounds) and cluster analysis revealed that: (i) mussel farms (32.7-70.1 ng g(-1)) are located in uncontaminated areas; (ii) coastal rockyshore areas (89.7 ± 25.8 ng g(-1)) have low level of contamination; and (iii) the Guanabara Bay (760.9 ± 456.3 ng g(-1)) is chronically contaminated by hydrocarbons, which is consistent with previous results. PAH profiles and diagnostic ratios suggested mixed petrogenic and pyrolitic sources for group (ii) and petrogenic sources for group (iii). The levels of PAH in the cultured and native mussels are below threshold values for safe food, even in Guanabara Bay, and thus in such cases other contaminants and pathogens should be considered in order to evaluate the quality of shellfish for human consumption. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Update on geographic spread of invasive lionfishes (Pterois volitans [Linnaeus, 1758] and P. miles [Bennett, 1828]) in the Western North Atlantic Ocean, Caribbean Sea and Gulf of Mexico

    USGS Publications Warehouse

    Schofield, Pamela J.

    2010-01-01

    The Indo-Pacific lionfishes (Pterois volitans [Linnaeus, 1758] and P. miles [Bennett, 1828]: Family Scorpaenidae) are the first nonnative marine fishes to establish in the Western North Atlantic/Caribbean region. The chronology of the invasion was reported last year (Schofield 2009) using records from the US Geological Survey's Nonindigenous Aquatic Species database. This article provides an update of lionfish geographic spread (as of October 2010) and predictions of future range.

  11. Difference in the wind speeds required for initiation versus continuation of sand transport on mars: implications for dunes and dust storms.

    PubMed

    Kok, Jasper F

    2010-02-19

    Much of the surface of Mars is covered by dunes, ripples, and other features formed by the blowing of sand by wind, known as saltation. In addition, saltation loads the atmosphere with dust aerosols, which dominate the Martian climate. We show here that saltation can be maintained on Mars by wind speeds an order of magnitude less than required to initiate it. We further show that this hysteresis effect causes saltation to occur for much lower wind speeds than previously thought. These findings have important implications for the formation of dust storms, sand dunes, and ripples on Mars.

  12. Intestinal helminths of the white stork (Ciconia ciconia Linnaeus 1758) from an inter-route site in Turkey.

    PubMed

    Girisgin, Ahmet Onur; Birlik, Sezen; Senlik, Bayram; Yildirimhan, Hikmet Sami

    2017-06-01

    In Turkey, a study was conducted during the years 2009-2015 to detect the gastrointestinal helminth species of 18 white storks (Ciconia ciconia Linnaeus, 1758 (Aves: Ciconiiformes) sampled from aquatic or swamp areas of Bursa Province, one of the inter-route sites where storks intensely stay. The results of postmortem examination revealed that 17 (94.44%) white storks harboured one or more helminth species. Eight species of helminths were detected at the following prevalence rates: Dictymetra discoidea (38.88%), Chaunocephalus ferox (37.50%), Schistocephalus solidus (27.77%), Stephanoprora (Monilifer) spinulosa (18.75%), Echinoparyphium sp. (12.50%), Tylodelphys excavata (6.25%), T. clavata (6.25%), and Syncuaria ciconiae (6.25%). This study is the first report on the presence of all the above species except T. excavata from white storks in Turkey. Stephanoprora (M.) spinulosa was found in Ciconiiform birds for the first time in this study.

  13. Microchromosome polymorphism in the sand lizard, Lacerta agilis Linnaeus, 1758 (Reptilia, Squamata)

    PubMed Central

    Lisachov, Artem P.; Borodin, Pavel M.

    2016-01-01

    Abstract Most true lizards (Lacertidae) share a conservative karyotype, consisting of 18 pairs of macrochromosomes and one microchromosome pair. Homeologues of the microchromosome are present in other squamates and even in chickens. No structural autosomal microchromosome polymorphisms have been described previously in lizards. We found homozygous and heterozygous carriers of a microchromosome variant in a Siberian population of the sand lizard, Lacerta agilis Linnaeus, 1758. The variant microchromosome was almost twice as long as the standard one. In heterozygotes at pachytene, the microchromosomes firstly pair in proximal regions and the central part of the longer axial element undergoes foldback synapsis, then its distal region pairs with the distal region of the standard partner. At metaphase-I, the heteromorphic microchromosome bivalents have a proximal chiasma. The content of the additional segment was Ag-NOR, C-like DAPI, CMA3 negative. FISH with telomere PNA probe did not detect interstitial (TTAGGG)n sequences in the heteromorphic and any other bivalents. Both homo- and heterozygous carriers were phenotypically normal. The presence of homozygotes shows that heterozygotes are fertile. Reduction in the number of microchromosomes is a clear trend in squamate evolution, as a result of microchromosomes fusing together or with macrochromosomes. Our findings indicate that gaining additional DNA may lead to a transformation of microchromosomes into small macrochromosomes without fusion. PMID:27830048

  14. Extensive fragmentation of the X chromosome in the bed bug Cimex lectularius Linnaeus, 1758 (Heteroptera, Cimicidae): a survey across Europe

    PubMed Central

    Sadílek, David; Šťáhlavský, František; Vilímová, Jitka; Zima, Jan

    2013-01-01

    Abstract Variation in the number of chromosomes was revealed in 61 samples of Cimex lectularius Linnaeus, 1758 from the Czech Republic and other European countries, hosted on Myotis Kaup, 1829 (4) and Homo sapiens Linnaeus, 1758 (57). The karyotype of all the specimens of Cimex lectularius analysed contained 26 autosomes and a varying number of the sex chromosomes. The number of sex chromosomes showed extensive variation, and up to 20 fragments were recorded. Altogether, 12 distinct karyotypes were distinguished. The male karyotypes consisted of 29, 30, 31, 32, 33, 34, 35, 36, 37, 40, 42 and 47 chromosomes. The females usually exhibited the number of chromosomes which was complementary to the number established in the males from the same sample. However, 11 polymorphic samples were revealed in which the karyotypes of females and males were not complementary each other. The complement with 2n = 26+X1X2Y was found in 44% of the specimens and 57,4% samples of bed bugs studied. The karyotypes with higher chromosome numbers as well as individuals with chromosomal mosaics were usually found within the samples exhibiting particularly extensive variation between individuals, and such complements were not found within samples contaning a few or single specimen. The occurrence of chromosomal mosaics with the karyotype constitution varying between cells of single individual was observed in five specimens (4.3%) from five samples. We assume that polymorphism caused by fragmentation of the X chromosome may result in meiotic problems and non-disjunction can produce unbalanced gametes and result in lowered fitness of individuals carrying higher numbers of the X chromosome fragments. This effect should be apparently enhanced with the increasing number of the fragments and this may be the reason for the observed distribution pattern of individual karyotypes in the studied samples and the rarity of individuals with extremely high chromosome numbers. The assumed lowering of the

  15. The relationship between concentration of clorophyll-a with skipjack (Katsuwonus pelamis, Linnaeus 1758) production at West Sumatera waters, Indonesia

    NASA Astrophysics Data System (ADS)

    Usman; Ersti Yulika Sari, T.; Syaifuddin; Audina

    2017-01-01

    The regression and correlation technic was uses to evaluated the contribution of chlorophyll-a concentration on variation of longline skipjack tuna production. An analysis was performed by placing Chlorophyll-a as predictor and Skipjack (Katsuwonus pelamis, Linnaeus 1758) production as dependent variable, using Chlorophyll-a derived from NPP VIIRS, and CPUE derived from longline fisherman log books for the year of 2013. Chlorophyll-a distribution which derived from NPP VIIRS between 0.13-0.26 mg/m3 whereas maximum CPUE as much as 0,1875 kg/trip in April. The regression equation obtained was CPUE = -1.12 + 11.5 Chl-a. Correlation between chlorophyll-a and CPUE have moderate relationship (r=0.51). From regression equation for those variables showed that the variation of chlorophyll-a had affected about 26% on variation of CPUE, only.

  16. The gold tegu, Tupinambis teguixin (Linnaeus, 1758) sensu lato (Squamata: Teiidae): evidence for an established population in Florida

    USGS Publications Warehouse

    Edwards, Jake R.; Ketterlin, Jennifer K.; Rochford, Michael R.; Irwin, Rodney; Krysko, Kenneth L.; Duquesnel, James G.; Mazzotti, Frank J.; Reed, Robert

    2017-01-01

    Gold tegus, Tupinambis teguixin (Linnaeus, 1758), are generalist predators from South America and are ecologically similar to Argentine black and white tegus (Salvator merianae), a successful invader in Florida. We trapped gold tegus in Broward and Miami-Dade counties, Florida, USA. In Miami-Dade County, collection occurred from 2008 through 2016. We combined new trapping records with previous literature records. Ten gold tegus of both sexes and multiple size classes over a nine year period indicate a reproducing population in Miami-Dade County. Tupinambis teguixin is the sixth established non-native teiid species in Florida. Additionally, we report Tupinambis teguixin from Sarasota and Lee counties, Florida, USA. Determining population status in those counties requires further study. It is critical to differentiate this species fromSalvator merianae during removal efforts. The possibility of eradicating Tupinambis teguixin exists if proper identification enables reliable monitoring of the populations.

  17. Effects of feeding, digestion and fasting on the respiration and swimming capability of juvenile sterlet sturgeon (Acipenser ruthenus, Linnaeus 1758).

    PubMed

    Cai, Lu; Johnson, David; Fang, Min; Mandal, Prashant; Tu, Zhiying; Huang, Yingping

    2017-02-01

    The objective of this study is to provide information on changes in swimming capability and respiration of the sterlet sturgeon (Acipenser ruthenus, Linnaeus 1758) caused by different levels of fasting. Before testing, the four groups of sturgeon (body length: 12.1-15.4 cm, body mass: 10.0-20.2 g) fasted for 6 h, 2 days, 1 and 2 weeks, respectively. Swimming tests were then performed to measure critical swimming speed and oxygen consumption at 20 ± 0.5 °C. Results show: (1) Fasting times shorter than 2 days has little effect on swimming capability, but it decreases significantly when the fasting time is longer than a week. (2) After 2 weeks of fasting, swimming efficiency is significantly reduced. (3) Anaerobic capacity increases when digestion nears completion.

  18. Accumulation of perfluorinated compounds in captive Bengal tigers (Panthera tigris tigris) and African lions (Panthera leo Linnaeus) in China.

    PubMed

    Li, Xuemei; Yeung, Leo Wai Yin; Taniyasu, Sachi; Lam, Paul K S; Yamashita, Nobuyoshi; Xu, Muqi; Dai, Jiayin

    2008-11-01

    The accumulation of perfluorinated compounds (PFCs) in the sera of captive wildlife species Bengal tigers (Panthera tigris tigris) and African lions (Panthera leo Linnaeus) from Harbin Wildlife Park, Heilongjiang Province, in China were analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Perfluorooctanesulfonate (PFOS) was the predominant contaminant with a mean serum concentration of 1.18 ng mL(-1) in tigers and 2.69 ng mL(-1) in lions. Perfluorononanoic acid (PFNA) was the second most prevalent contaminant in both species. The composition profiles of the tested PFCs differed between tigers and lions, and the percentages of perfluorooctanoic acid (PFOA) were greater in lions than in tigers, indicating different exposures and/or metabolic capabilities between the two species. Assessments of the risk of PFC contamination to the two species were obtained by comparing measured concentrations to points of departure or toxicity reference values (TRVs). Results suggest no risk of PFOS exposure or toxicity for the two species.

  19. First isolation and RFLP genotyping of Toxoplasma gondii from crab-eating fox (Cerdocyon thous-Linnaeus, 1766).

    PubMed

    de Almeida, Jonatas Campos; de Melo, Renata Pimentel Bandeira; de Morais Pedrosa, Camila; da Silva Santos, Marcelo; de Barros, Luiz Daniel; Garcia, João Luis; Porto, Wagnner José Nascimento; Mota, Rinaldo Aparecido

    2017-05-01

    Wild animals may play an important role in the transmission and maintenance of Toxoplasma gondii in the environment. The purpose of the present study was to isolate and genotype T. gondii from a free-ranging crab-eating fox (Cerdocyon thous-Linnaeus, 1766). A crab-eating fox in critical health condition was attended in a veterinary hospital in Recife, Pernambuco State, Brazil. The animal died despite emergency treatment. The brain was collected aseptically and destined for mouse bioassay. One isolate of T. gondii was obtained, and Polymerase Chain Reaction - Restriction Fragment Length Polymorphism (PCR-RFLP) was used to assess genetic variability at 11 markers (SAG1, SAG2, altSAG2, SAG3, BTUB, GRA6, c228, c292, L358, PK1 and APICO). A murine model was used to assess the virulence of the isolate. Using the PCR-RFLP, genotype ToxoDB #13 was identified, which is considered an atypical strain. The isolate was classified as avirulent in the murine model. This is the first study to report T. gondii infection in the crab-eating fox. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Metallothionein in Hermetia illucens (Linnaeus, 1758) larvae (Diptera: Stratiomyidae), a potential biomarker for organic waste system.

    PubMed

    Wang, Xiaoyun; Gao, Qiao; Liu, Xinhui; Wang, Xiao-Ping; Lei, Chaoliang; Sayed, Waheed A A; Zhu, Fen

    2018-02-01

    Black soldier fly, Hermetia illucens (Linnaeus, 1758), is an important economic fly as its larvae can be used for recycling organic waste, such as food waste and manure. H. illucens larvae (BSFL) could uptake Cd from substrates and accumulate it inside bodies, which need to be monitored during waste treatment. Metallothionein (MT) usually serve as biomarker because of its role in metal homeostasis, detoxification, and dose response of heavy metals. Therefore, a MT gene was cloned from H. illucens (HIMT) that encoded 40 amino acids with typical cysteine rich features, which had a high sequence identity with other insect MTs. The expression of HIMT and total MT protein was measured in BSFL fed by meals spiked with gradient dose of Cd (0, 5, 50, 500 mg/kg) for 24, 48, 72, and 96 h, respectively. Dose-associated response of HIMT and total MT were found and the possible correlative range of Cd was from 5 to 50 mg/kg. The expression of HIMT might be a potential biomarker for monitoring Cd contamination by H. illucens in terrestrial organic matters, which might further apply in waste transformation system.

  1. Ontogenetic development of digestive functionality in golden pompano Trachinotus ovatus (Linnaeus 1758).

    PubMed

    Ma, Zhenhua; Guo, Huayang; Zheng, Panlong; Wang, Long; Jiang, Shigui; Qin, Jian G; Zhang, Dianchang

    2014-08-01

    Ontogenetic development of the digestive system in golden pompano (Trachinotus ovatus, Linnaeus 1758) larvae was histologically and enzymatically studied from hatch to 32 day post-hatch (DPH). The development of digestive system in golden pompano can be divided into three phases: phase I starting from hatching and ending at the onset of exogenous feeding; phase II starting from first feeding (3 DPH) and finishing at the formation of gastric glands; and phase III starting from the appearance of gastric glands on 15 DPH and continuing onward. The specific activities of trypsin, amylase, and lipase increased sharply from the onset of first feeding to 5-7 DPH, followed by irregular fluctuations. Toward the end of this study, the specific activities of trypsin and amylase showed a declining trend, while the lipase activity remained at similar levels as it was at 5 DPH. The specific activity of pepsin was first detected on 15 DPH and increased with fish age. The dynamics of digestive enzymes corresponded to the structural development of the digestive system. The enzyme activities tend to be stable after the formation of the gastric glands in fish stomach on 15 DPH. The composition of digestive enzymes in larval pompano indicates that fish are able to digest protein, lipid and carbohydrate at early developmental stages. Weaning of larval pompano is recommended from 15 DPH onward. Results of the present study lead to a better understanding of the ontogeny of golden pompano during the larval stage and provide a guide to feeding and weaning of this economically important fish in hatcheries.

  2. Castosyringophilus meropis sp. n. (Acariformes: Syringophilidae) - a new quill mite species parasitising the world population of Merops apiaster Linnaeus (Coraciiformes: Meropidae).

    PubMed

    Skoracki, Maciej; Hromada, Martin; Sikora, Bozena

    2017-07-26

    A new species, Castosyringophilus meropis sp. n., found in quills of feathers of the European bee-eater Merops apiaster Linnaeus (Coraciiformes: Meropidae) is described. This new species is close to C. claravis Skoracki et Glowska, 2008 and differs, in females, by the presence apunctate coxal fields (vs sparsely punctate in C. claravis) and by the lengths of setae d1 145-180 µm, f2 170-185 µm and ag3 190-215 µm (vs d1 200-220 µm, f2 230-250 µm and ag3 150-170 µm). We present a vast mite material collected from bee-eaters originated from different localities in Europe, Asia and Africa, both breeding and wintering grounds of this bird. It indicates that the whole world population of the European bee-eater is parasitised by this quill mite species.

  3. Preparation of purified fractions for polysaccharides from Monetaria moneta Linnaeus and comparison their characteristics and antioxidant activities.

    PubMed

    Yuan, Jun; Chen, Shuxian; Wang, Liping; Xu, Tingting; Shi, Xu; Jing, Yi; Zhang, Haijiang; Huang, Yange; Xu, Ying; Li, Dong; Chen, Xing; Chen, Jianhui; Xiong, Qingping

    2018-03-01

    The aim of this paper was to prepare purified fractions of polysaccharides from Monetaria moneta Linnaeus and further compare their characteristics and antioxidant activities. Firstly, three novel purified fractions, named MM-P1, MM-P2 and MM-P3, were successfully prepared by a DEAE-Sepharose fast-flow column. Then, their characteristics were compared using chemical testing, FT-IR, GC and HPGPC. The results suggested that MM-P3 had higher molecular weights than MM-P1 and MM-P2. MM-P1 was consisted of glucose, MM-P2 was consisted of glucose and xylose, and MM-P3 was comprised of glucose, xylose and mannose. Differed from MM-P1 and MM-P2, MM-P3 had sulfuric radical and uronic acid groups. Finally, their antioxidant activities were also compared. We found that MM-P3 exhibited better antioxidant bioactivities than MM-P1 and MM-P2. The data demonstrated that three purified fractions derived from different adsorption capacity of DEAE-Sepharose fast-flow column possessed different structural characteristics and antioxidant activity. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Karyotype characterization and comparison of three hexaploid species of Bromus Linnaeus, 1753 (Poaceae)

    PubMed Central

    Artico, Leonardo Luís; Mazzocato, Ana Cristina; Ferreira, Juliano Lino; Carvalho, Carlos Roberto; Clarindo, Wellington Ronildo

    2017-01-01

    Abstract Chromosome morphometry and nuclear DNA content are useful data for cytotaxonomy and to understand the evolutionary history of different taxa. For the genus Bromus Linnaeus, 1753, distinct ploidy levels have been reported, occurring from diploid to duodecaploid species. The geographic distribution of Bromus species has been correlated with chromosome number and ploidy level. In this study, the aims were to determine the nuclear genome size and characterize the karyotype of the South American Bromus species: Bromus auleticus Trinius ex Nees, 1829, Bromus brachyanthera Döll, 1878 and Bromus catharticus Vahl, 1791. The mean nuclear 2C value ranged from 2C = 12.64 pg for B. catharticus to 2C = 17.92 pg for B. auleticus, meaning a maximum variation of 2C = 5.28 pg, equivalent to 41.70%. Despite this significant difference in 2C value, the three species exhibit the same chromosome number, 2n = 6x = 42, which confirms their hexaploid origin. Corroborating the genome size, the chromosome morphometry (total, short- and long-arm length) and, consequently, the class differed among the karyotypes of the species. Based on the first karyograms for these Bromus species, some morphologically similar and several distinct chromosome pairs were found. Therefore, the karyotype characterization confirmed the hexaploid origin of the studied Bromus species, which differ in relation to the karyogram and the nuclear 2C value. Considering this, cytogenetics and flow cytometry can be used to discriminate Bromus species, contributing to taxonomy and systematic studies and providing information on the evolutionary history of this taxa. PMID:28919960

  5. Karyotype characterization and comparison of three hexaploid species of Bromus Linnaeus, 1753 (Poaceae).

    PubMed

    Artico, Leonardo Luís; Mazzocato, Ana Cristina; Ferreira, Juliano Lino; Carvalho, Carlos Roberto; Clarindo, Wellington Ronildo

    2017-01-01

    Chromosome morphometry and nuclear DNA content are useful data for cytotaxonomy and to understand the evolutionary history of different taxa. For the genus Bromus Linnaeus, 1753, distinct ploidy levels have been reported, occurring from diploid to duodecaploid species. The geographic distribution of Bromus species has been correlated with chromosome number and ploidy level. In this study, the aims were to determine the nuclear genome size and characterize the karyotype of the South American Bromus species: Bromus auleticus Trinius ex Nees, 1829, Bromus brachyanthera Döll, 1878 and Bromus catharticus Vahl, 1791. The mean nuclear 2C value ranged from 2C = 12.64 pg for B. catharticus to 2C = 17.92 pg for B. auleticus , meaning a maximum variation of 2C = 5.28 pg, equivalent to 41.70%. Despite this significant difference in 2C value, the three species exhibit the same chromosome number, 2n = 6x = 42, which confirms their hexaploid origin. Corroborating the genome size, the chromosome morphometry (total, short- and long-arm length) and, consequently, the class differed among the karyotypes of the species. Based on the first karyograms for these Bromus species, some morphologically similar and several distinct chromosome pairs were found. Therefore, the karyotype characterization confirmed the hexaploid origin of the studied Bromus species, which differ in relation to the karyogram and the nuclear 2C value. Considering this, cytogenetics and flow cytometry can be used to discriminate Bromus species, contributing to taxonomy and systematic studies and providing information on the evolutionary history of this taxa.

  6. On the morphology of the worker immatures of the leafcutter ant Atta sexdens Linnaeus (Hymenoptera: Formicidae).

    PubMed

    Solis, Daniel Russ; Fox, Eduardo Gonçalves Paterson; Ceccato, Marcela; Reiss, Itamar Cristina; Décio, Pâmela; Lorenzon, Natalia; Da Silva, Natiele Gonçalves; Bueno, Odair Correa

    2012-08-01

    Leafcutter ants of the genus Atta Fabricius are serious agricultural pests. Morphological studies of immature stages within this group are few, and the data provided for species of considerable importance are usually incomplete. In this study, the immatures of Atta sexdens Linnaeus are described and compared using light and scanning electron microscopy. Only specimens from founding stage colonies (i.e., lacking adult workers) were used. The existence of four larval instars was estimated by a frequency plot of maximum head widths, and the larvae of different instars differed from each other mainly by their bodily dimensions. Worker larvae belonged to two distinct morphological castes: (1) gardeners and nurses and (2) within-nest generalists. The worker larvae described in this study differed from a previous description of the same species by the following traits: the existence of a genal lobe, the number of clypeal hairs, the presence of two hairs on the ninth abdominal somite, the presence of hairs on the anterior surface of the labrum, and the shape of the maxillary palpus. This study provides a comparative analysis of immature stages of A. sexdens that may be relevant to future morphological and biological studies of the Attini. Copyright © 2012 Wiley Periodicals, Inc.

  7. The Mediterranean stony coral Cladocora caespitosa (Linnaeus, 1767) as habitat provider for molluscs: colony size effect

    NASA Astrophysics Data System (ADS)

    Pitacco, Valentina; Crocetta, Fabio; Orlando-Bonaca, Martina; Mavrič, Borut; Lipej, Lovrenc

    2017-11-01

    The stony coral Cladocora caespitosa (Linnaeus, 1767) is an important Mediterranean habitat builder, whose survival is now being threatened by human activities and possibly natural events such as mass mortality and bleaching. We characterized the mollusc assemblage associated with colonies in the Gulf of Trieste (northern Adriatic Sea) and then tested whether the number of mollusc species increases in relation with colony size, following a Species-Area Relationship (SAR) model. At least 62 taxa were found in association with coral colonies, with bivalves constituting the dominant group. More than half of the 3034 specimens encountered were juveniles. Mollusc taxa richness increased with increasing C. caespitosa colony size according to the power-function model, whilst the analyses of trophic and functional groups supports the hypothesis of at least two factors underlying SAR (area per se and habitat diversity). Our results confirmed the importance of C. caespitosa for benthic communities, indicating that larger colonies support higher biodiversity, and suggesting that C. caespitosa is the most important habit builder among Mediterranean cnidarians, having also an influential function as a natural nursery ground. These results underline the necessity of new investigations aimed at filling gaps in our knowledge and planning new measures to protect the species.

  8. The morphology and histology of the male reproductive system in Dolycoris baccarum Linnaeus 1758 (Heteroptera: Pentatomidae)--light and scanning electron micoscope studies.

    PubMed

    Özyurt, Nurcan; Candan, Selami; Suludere, Zekiye

    2013-01-01

    The male reproductive system of Dolycoris baccarum (Linnaeus 1758) is studied morphologically and histologically using both light and scanning electron microscopes (SEM). The reproductive system of the male D. baccarum consists of a pair of testis, a pair of vas deferens, a pair of seminal vesicles, accessory glands (mesadenia, ectadenia), a bulbus ejaculatorius, a pair of ectodermal sacs, and a ductus ejaculatorius. The number of testicular follicles varies from four to six. The testicular follicles have three different development zones (growth zone, maturation zone, differentiation zone). The testes are connected to the seminal vesicles by the vas deferens. Vas deferens and seminal vesicles, which are fine-long and cylindrical. The seminal vesicle is connected with bulbus ejaculatorius which is balloon-shaped and surrounded with accessory glands. The bulbus ejaculatorius is continuous with ductus ejaculatorius which connected to the aedeagus. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Structural and ultrastructural features of the agouti tongue (Dasyprocta aguti Linnaeus, 1766)

    PubMed Central

    Ciena, Adriano Polican; Bolina, Cristina de Sousa; de Almeida, Sonia Regina Yokomizo; Rici, Rose Eli Grassi; de Oliveira, Moacir Franco; da da Silva, Marcelo Cavenaghi Pereira; Miglino, Maria Angélica; Watanabe, Ii-sei

    2013-01-01

    The agouti (Dasyprocta aguti Linnaeus, 1766) is a wild rodent belonging to the family Dasyproctidae that is found throughout Brazil and feeds on fruits and seeds. The aim of the present study was to describe the following features of the tongue of agouti: its morphological structures, the three-dimensional characteristics of the lingual papillae surface, the connective tissue cores (CTCs) and the epithelial cell ultrastructure. Four types of papillae were observed on the dorsal surface of the tongue with a triangular shape: filiform, fungiform, foliate and vallate. Filiform papillae were distributed throughout the tongue surface, and removal of the epithelial surface revealed conical CTCs and multifilaments. Fungiform papillae were observed in the rostral and middle regions, whereas foliate papillae developed in pairs on the lateral margin of the caudal region. Removal of the epithelium in these regions revealed CTCs with parallel laminar conformation. Vallate papillae were arranged in a V-shape in the caudal region, and their CTCs ranged in shape from elongate to ovoid. The ultrastructural components of the dorsal epithelium were the basal, spinous, granular and keratinised layers. A broad area with cytoplasmic projections was identified in the interface region between the lamina propria and the basal layer. Flattened cells with intermediate filaments were observed in the transitional region between spinous and granular layers. The keratinised layer was composed of superimposed epithelial cells where desmosomes and cell-surface microridges were observed. These structural features, including the three-dimensional aspects of the lingual papillae, the CTCs and the epithelial ultrastructure, indicate that when compared with other animals, particularly other rodent species, the morphological features of the tongue of agouti are relatively well developed, especially regarding foliate and vallate papillae. PMID:23701183

  10. Optimal-rearing density for head-starting green turtles (Chelonia mydas Linnaeus, 1758).

    PubMed

    Kanghae, Hirun; Thongprajukaew, Karun; Jatupornpitukchat, Sasiporn; Kittiwattanawong, Kongkiat

    2016-09-01

    While ex situ conservation programs of juvenile green turtles (Chelonia mydas Linnaeus, 1758), before release to natural habitats, have been conducted in several countries, the optimal-stocking density for husbandry has not yet been reported. The optimization of stocking density was the main purpose of this study. The 15-day-old post-hatching turtles (29.30 ± 0.05 g body weight) were reared in round fiberglass tanks at various stocking densities including 20 turtles/m 3 (20TM), 40 turtles/m 3 (40TM), 60 turtles/m 3 (60TM), and 80 turtles/m 3 (80TM), over an 8-week trial. Water quality, survival, growth performance, feed utilization, aggressive behavior, fecal digestive enzymes, and hematological parameters were compared between the treatments, and were used as indicators of a successful captive rearing program. The water quality across the four treatments was in the standard range, but a high-stocking density reduced the quality significantly. No mortality was observed in any treatment group. Superior growth and feed utilization were only observed with the 40TM treatment, relative to the others (P < 0.05). The turtles in this group had no aggressive behavior, as indicated by observing hind limb biting. This treatment manipulated the level of proteolytic activity of pepsin and trypsin in response to density stressor, but not amylase, lipase, and chymotrypsin. The 40TM treatment also maintained the hematological characteristics, indicating no negative effects on health status. Overall, the findings indicate that the captivity program of post-hatching turtles at 40 turtles/m 3 is the preferred option in their head-started propagation, as well as in public displays in zoos or aquaria. Zoo Biol. 35:454-461, 2016. © Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

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

    Pähtz, Thomas, E-mail: 0012136@zju.edu.cn; State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, 310012 Hangzhou; Durán, Orencio

    Here, we compare two extreme regimes of non-suspended fluid-mediated particle transport, transport in light and heavy fluids (“saltation” and “bedload,” respectively), regarding their particle fluctuation energy balance. From direct numerical simulations, we surprisingly find that the ratio between collisional and fluid drag dissipation of fluctuation energy is significantly larger in saltation than in bedload, even though the contribution of interparticle collisions to transport of momentum and energy is much smaller in saltation due to the low concentration of particles in the transport layer. We conclude that the much higher frequency of high-energy particle-bed impacts (“splash”) in saltation is the causemore » for this counter-intuitive behavior. Moreover, from a comparison of these simulations to particle tracking velocimetry measurements which we performed in a wind tunnel under steady transport of fine and coarse sand, we find that turbulent fluctuations of the flow produce particle fluctuation energy at an unexpectedly high rate in saltation even under conditions for which the effects of turbulence are usually believed to be small.« less

  12. Large-scale variability of wind erosion mass flux rates at Owens Lake 1. Vertical profiles of horizontal mass fluxes of wind-eroded particles with diameter greater than 50 μm

    USGS Publications Warehouse

    Gillette, Dale A.; Fryrear, D.W.; Xiao, Jing Bing; Stockton, Paul; Ono, Duane; Helm, Paula J.; Gill, Thomas E; Ley, Trevor

    1997-01-01

    A field experiment at Owens (dry) Lake, California, tested whether and how the relative profiles of airborne horizontal mass fluxes for >50-μm wind-eroded particles changed with friction velocity. The horizontal mass flux at almost all measured heights increased proportionally to the cube of friction velocity above an apparent threshold friction velocity for all sediment tested and increased with height except at one coarse-sand site where the relative horizontal mass flux profile did not change with friction velocity. Size distributions for long-time-averaged horizontal mass flux samples showed a saltation layer from the surface to a height between 30 and 50 cm, above which suspended particles dominate. Measurements from a large dust source area on a line parallel to the wind showed that even though the saltation flux reached equilibrium ∼650 m downwind of the starting point of erosion, weakly suspended particles were still input into the atmosphere 1567 m downwind of the starting point; thus the saltating fraction of the total mass flux decreased after 650 m. The scale length difference and ratio of 70/30 suspended mass flux to saltation mass flux at the farthest down wind sampling site confirm that suspended particles are very important for mass budgets in large source areas and that saltation mass flux can be a variable fraction of total horizontal mass flux for soils with a substantial fraction of <100-μm particles.

  13. Determination of oral bioavailability of curcuminoid dispersions and nanoemulsions prepared from Curcuma longa Linnaeus.

    PubMed

    Lu, Pei Shan; Inbaraj, Baskaran Stephen; Chen, Bing Huei

    2018-01-01

    Curcuminoid from Curcuma longa Linnaeus has been demonstrated to be effective in anti-cancer and anti-inflammation. The objectives of the present study were to prepare curcuminoid dispersion and nanoemulsion from C. longa and determine their oral bioavailabilities in rats. After curcuminoid extraction using 99.5% ethanol, bisdemethoxycurcumin (BDMC), demethoxycurcumin (DMC) and curcumin were separated within 10 min by high-performance liquid chromatography using an Eclipse XDB-C18 column (Agilent, Palo Alto, CA, USA) and a gradient mobile phase of 0.1% aqueous formic acid and acetonitrile, with a flow rate of 1 mL min -1 , column temperature of 35 °C and detection wavelength of 425 nm. Curcuminoid nanoemulsion at a particle size of 12.1 nm and encapsulation efficiency 98.8% was prepared using lecithin, Tween 80 and water. A pharmacokinetic study in rats revealed that the parameters including T max , C max , t 1/2 and the area under the curve were higher for curcuminoid nanoemulsions than for curcuminoid dispersion at the same dose employed for gavage administration, whereas, for intravenous injection, an opposite trend was shown. The oral bioavailabilities of BDMC, DMC, curcumin and total curcuminoids in nanoemulsion and dispersion were 34.39 and 4.65%, 39.93 and 5.49%, 47.82 and 9.38%, and 46 and 8.7%, respectively. The results of the present study demonstrate a higher oral bioavailability after incorporation of curcuminoid into nanoemulsion, facilitating its application as a botanic drug. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  14. 7 CFR 361.6 - Noxious weed seeds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... & Levier Hydrilla verticillata (Linnaeus f.) Royle Hygrophila polysperma T. Anderson Imperata brasiliensis Trinius Imperata cylindrica (Linnaeus) Palisot de Beauvois Inula britannica Linnaeus Ipomoea aquatica...

  15. 7 CFR 361.6 - Noxious weed seeds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... & Levier Hydrilla verticillata (Linnaeus f.) Royle Hygrophila polysperma T. Anderson Imperata brasiliensis Trinius Imperata cylindrica (Linnaeus) Palisot de Beauvois Inula britannica Linnaeus Ipomoea aquatica...

  16. 7 CFR 361.6 - Noxious weed seeds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... & Levier Hydrilla verticillata (Linnaeus f.) Royle Hygrophila polysperma T. Anderson Imperata brasiliensis Trinius Imperata cylindrica (Linnaeus) Palisot de Beauvois Inula britannica Linnaeus Ipomoea aquatica...

  17. Collection and collation: theory and practice of Linnaean botany.

    PubMed

    Müller-Wille, Staffan

    2007-09-01

    Historians and philosophers of science have interpreted the taxonomic theory of Carl Linnaeus (1707-1778) as an 'essentialist', 'Aristotelian', or even 'scholastic' one. This interpretation is flatly contradicted by what Linnaeus himself had to say about taxonomy in Systema naturae (1735), Fundamenta botanica (1736) and Genera plantarum (1737). This paper straightens out some of the more basic misinterpretations by showing that: (1) Linnaeus's species concept took account of reproductive relations among organisms and was therefore not metaphysical, but biological; (2) Linnaeus did not favour classification by logical division, but criticized it for necessarily failing to represent what he called 'natural' genera; (3) Linnaeus's definitions of 'natural' genera and species were not essentialist, but descriptive and polytypic; (4) Linnaeus's method in establishing 'natural' definitions was not deductive, but consisted in an inductive, bottom-up procedure of comparing concrete specimens. The conclusion will discuss the fragmentary and provisional nature of Linnaeus's 'natural method'. I will argue in particular that Linnaeus opted for inductive strategies not on abstract epistemological grounds, but in order to confer stability and continuity to the explorative practices of contemporary natural history.

  18. Emergent properties of gene evolution: Species as attractors in phenotypic space

    NASA Astrophysics Data System (ADS)

    Reuveni, Eli; Giuliani, Alessandro

    2012-02-01

    The question how the observed discrete character of the phenotype emerges from a continuous genetic distance metrics is the core argument of two contrasted evolutionary theories: punctuated equilibrium (stable evolution scattered with saltations in the phenotype) and phyletic gradualism (smooth and linear evolution of the phenotype). Identifying phenotypic saltation on the molecular levels is critical to support the first model of evolution. We have used DNA sequences of ∼1300 genes from 6 isolated populations of the budding yeast Saccharomyces cerevisiae. We demonstrate that while the equivalent measure of the genetic distance show a continuum between lineage distance with no evidence of discrete states, the phenotypic space illustrates only two (discrete) possible states that can be associated with a saltation of the species phenotype. The fact that such saltation spans large fraction of the genome and follows by continuous genetic distance is a proof of the concept that the genotype-phenotype relation is not univocal and may have severe implication when looking for disease related genes and mutations. We used this finding with analogy to attractor-like dynamics and show that punctuated equilibrium could be explained in the framework of non-linear dynamics systems.

  19. Antibacterial activity of GUAVA, Psidium guajava Linnaeus, leaf extracts on diarrhea-causing enteric bacteria isolated from Seabob shrimp, Xiphopenaeus kroyeri (Heller).

    PubMed

    Gonçalves, Flávia A; Andrade Neto, Manoel; Bezerra, José N S; Macrae, Andrew; Sousa, Oscarina Viana de; Fonteles-Filho, Antonio A; Vieira, Regine H S F

    2008-01-01

    Guava leaf tea of Psidium guajava Linnaeus is commonly used as a medicine against gastroenteritis and child diarrhea by those who cannot afford or do not have access to antibiotics. This study screened the antimicrobial effect of essential oils and methanol, hexane, ethyl acetate extracts from guava leaves. The extracts were tested against diarrhea-causing bacteria: Staphylococcus aureus, Salmonella spp. and Escherichia coli. Strains that were screened included isolates from seabob shrimp, Xiphopenaeus kroyeri (Heller) and laboratory-type strains. Of the bacteria tested, Staphylococcus aureus strains were most inhibited by the extracts. The methanol extract showed greatest bacterial inhibition. No statistically significant differences were observed between the tested extract concentrations and their effect. The essential oil extract showed inhibitory activity against S. aureus and Salmonella spp. The strains isolated from the shrimp showed some resistance to commercially available antibiotics. These data support the use of guava leaf-made medicines in diarrhea cases where access to commercial antibiotics is restricted. In conclusion, guava leaf extracts and essential oil are very active against S. aureus, thus making up important potential sources of new antimicrobial compounds.

  20. Circulating Hemocytes from Larvae of the Japanese Rhinoceros Beetle Allomyrina dichotoma (Linnaeus) (Coleoptera: Scarabaeidae) and the Cellular Immune Response to Microorganisms.

    PubMed

    Hwang, Sejung; Bang, Kyeongrin; Lee, Jiae; Cho, Saeyoull

    2015-01-01

    Hemocytes of the last larva of the Japanese rhinoceros beetle A. dichotoma (Linnaeus) (Coleoptera: Scarabaeidae) were classified as granulocytes, plasmatocytes, oenocytoids, spherulocytes, prohemocytes, and adipohemocytes. Among these cell types, only the granulocytes became immunologically activated with obvious morphological changes, displaying large amoeba-like, lobopodia-like, and fan-like structures. In addition, their cytoplasmic granules became larger and greatly increased in number. To explore whether these granules could be immunologically generated as phagosomes, total hemocytes were stained with LysoTracker. Greater than 90% of the granulocytes retained the LysoTracker dye at 4 h post-bacterial infection. In flow cytometry analysis, the red fluorescent signal was highly increased at 4 h post-bacterial infection (60.36%) compared to controls (5.08%), as was confirmed by fluorescent microscopy. After 12 h post-infection, these signals returned to basal levels. The uptake of pathogens by granulocytes rapidly triggered the translocation of the microtubule-associated protein 1 light chain 3 alpha (LC3) to the phagosome, which may result in enhanced pathogen killing.

  1. Circulating Hemocytes from Larvae of the Japanese Rhinoceros Beetle Allomyrina dichotoma (Linnaeus) (Coleoptera: Scarabaeidae) and the Cellular Immune Response to Microorganisms

    PubMed Central

    Hwang, Sejung; Bang, Kyeongrin; Lee, Jiae; Cho, Saeyoull

    2015-01-01

    Hemocytes of the last larva of the Japanese rhinoceros beetle A. dichotoma (Linnaeus) (Coleoptera: Scarabaeidae) were classified as granulocytes, plasmatocytes, oenocytoids, spherulocytes, prohemocytes, and adipohemocytes. Among these cell types, only the granulocytes became immunologically activated with obvious morphological changes, displaying large amoeba-like, lobopodia-like, and fan-like structures. In addition, their cytoplasmic granules became larger and greatly increased in number. To explore whether these granules could be immunologically generated as phagosomes, total hemocytes were stained with LysoTracker. Greater than 90% of the granulocytes retained the LysoTracker dye at 4 h post-bacterial infection. In flow cytometry analysis, the red fluorescent signal was highly increased at 4 h post-bacterial infection (60.36%) compared to controls (5.08%), as was confirmed by fluorescent microscopy. After 12 h post-infection, these signals returned to basal levels. The uptake of pathogens by granulocytes rapidly triggered the translocation of the microtubule-associated protein 1 light chain 3 alpha (LC3) to the phagosome, which may result in enhanced pathogen killing. PMID:26030396

  2. Interactions of 2,4,6-trinitrotoluene (TNT) with xenobiotic biotransformation system in European eel Anguilla anguilla (Linnaeus, 1758).

    PubMed

    Della Torre, Camilla; Corsi, Ilaria; Arukwe, Augustine; Valoti, Massimo; Focardi, Silvano

    2008-11-01

    The aim of the present study was to investigate the interaction of 2,4,6-trinitrotoluene (TNT) with liver biotransformation enzymes in European eel Anguilla anguilla (Linnaeus, 1758). Eels were exposed to 0.5, 1 and 2.5mg/l nominal concentrations of TNT for 6 and 24h. Modulation of CYP1A1, UDPGT and GST genes was investigated by real-time PCR. Total CYP450 content, NADPH cytochrome c reductase activity, CYP1A and CYP2B-like activities, such as EROD, MROD and BROD, as well as GST and UDPGT activities, were measured by biochemical assays. An in vitro study was performed on EROD in order to evaluate catalytic modulation by TNT. No modulation of the CYP1A1 gene or protein was observed in TNT-exposed eels. On the other hand, a significant decline of EROD and MROD activities was observed in vivo. An increase in NADPH cyt c reductase, and phase II enzymes (UDPGT and GST) were observed at both gene expression and activity levels. The overall results indicated that TNT is a potential competitive inhibitor of CYP1A activities. A TNT metabolic pathway involving NADPH cyt c reductase and phase II enzymes is also suggested.

  3. Insecticidal activity of garlic essential oil and their constituents against the mealworm beetle, Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae).

    PubMed

    Plata-Rueda, Angelica; Martínez, Luis Carlos; Santos, Marcelo Henrique Dos; Fernandes, Flávio Lemes; Wilcken, Carlos Frederico; Soares, Marcus Alvarenga; Serrão, José Eduardo; Zanuncio, José Cola

    2017-04-20

    This study evaluated the insecticidal activity of garlic, Allium sativum Linnaeus (Amaryllidaceae) essential oil and their principal constituents on Tenebrio molitor. Garlic essential oil, diallyl disulfide, and diallyl sulfide oil were used to compare the lethal and repellent effects on larvae, pupae and adults of T. molitor. Six concentrations of garlic essential oil and their principal constituents were topically applied onto larvae, pupae and adults of this insect. Repellent effect and respiration rate of each constituent was evaluated. The chemical composition of garlic essential oil was also determined and primary compounds were dimethyl trisulfide (19.86%), diallyl disulfide (18.62%), diallyl sulfide (12.67%), diallyl tetrasulfide (11.34%), and 3-vinyl-[4H]-1,2-dithiin (10.11%). Garlic essential oil was toxic to T. molitor larva, followed by pupa and adult. In toxic compounds, diallyl disulfide was the most toxic than diallyl sulfide for pupa > larva > adult respectively and showing lethal effects at different time points. Garlic essential oil, diallyl disulfide and diallyl sulfide induced symptoms of intoxication and necrosis in larva, pupa, and adult of T. molitor between 20-40 h after exposure. Garlic essential oil and their compounds caused lethal and sublethal effects on T. molitor and, therefore, have the potential for pest control.

  4. Insecticidal activity of garlic essential oil and their constituents against the mealworm beetle, Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae)

    PubMed Central

    Plata-Rueda, Angelica; Martínez, Luis Carlos; Santos, Marcelo Henrique Dos; Fernandes, Flávio Lemes; Wilcken, Carlos Frederico; Soares, Marcus Alvarenga; Serrão, José Eduardo; Zanuncio, José Cola

    2017-01-01

    This study evaluated the insecticidal activity of garlic, Allium sativum Linnaeus (Amaryllidaceae) essential oil and their principal constituents on Tenebrio molitor. Garlic essential oil, diallyl disulfide, and diallyl sulfide oil were used to compare the lethal and repellent effects on larvae, pupae and adults of T. molitor. Six concentrations of garlic essential oil and their principal constituents were topically applied onto larvae, pupae and adults of this insect. Repellent effect and respiration rate of each constituent was evaluated. The chemical composition of garlic essential oil was also determined and primary compounds were dimethyl trisulfide (19.86%), diallyl disulfide (18.62%), diallyl sulfide (12.67%), diallyl tetrasulfide (11.34%), and 3-vinyl-[4H]-1,2-dithiin (10.11%). Garlic essential oil was toxic to T. molitor larva, followed by pupa and adult. In toxic compounds, diallyl disulfide was the most toxic than diallyl sulfide for pupa > larva > adult respectively and showing lethal effects at different time points. Garlic essential oil, diallyl disulfide and diallyl sulfide induced symptoms of intoxication and necrosis in larva, pupa, and adult of T. molitor between 20–40 h after exposure. Garlic essential oil and their compounds caused lethal and sublethal effects on T. molitor and, therefore, have the potential for pest control. PMID:28425475

  5. The effect of adsorbed liquid and material density on saltation threshold: Insight from laboratory and wind tunnel experiments

    NASA Astrophysics Data System (ADS)

    Yu, Xinting; Hörst, Sarah M.; He, Chao; Bridges, Nathan T.; Burr, Devon M.; Sebree, Joshua A.; Smith, James K.

    2017-11-01

    Saltation threshold, the minimum wind speed for sediment transport, is a fundamental parameter in aeolian processes. Measuring this threshold using boundary layer wind tunnels, in which particles are mobilized by flowing air, for a subset of different planetary conditions can inform our understanding of physical processes of sediment transport. The presence of liquid, such as water on Earth or methane on Titan, may affect the threshold values to a great extent. Sediment density is also crucial for determining threshold values. Here we provide quantitative data on density and water content of common wind tunnel materials (including chromite, basalt, quartz sand, beach sand, glass beads, gas chromatograph packing materials, walnut shells, iced tea powder, activated charcoal, instant coffee, and glass bubbles) that have been used to study conditions on Earth, Titan, Mars, and Venus. The measured density values for low density materials are higher compared to literature values (e.g., ∼30% for walnut shells), whereas for the high density materials, there is no such discrepancy. We also find that low density materials have much higher water content and longer atmospheric equilibration timescales compared to high density sediments. We used thermogravimetric analysis (TGA) to quantify surface and internal water and found that over 80% of the total water content is surface water for low density materials. In the Titan Wind Tunnel (TWT), where Reynolds number conditions similar to those on Titan can be achieved, we performed threshold experiments with the standard walnut shells (125-150 μm, 7.2% water by mass) and dried walnut shells, in which the water content was reduced to 1.7%. The threshold results for the two scenarios are almost the same, which indicates that humidity had a negligible effect on threshold for walnut shells in this experimental regime. When the water content is lower than 11.0%, the interparticle forces are dominated by adsorption forces, whereas at

  6. The mitochondrial phylogeny of an ancient lineage of ray-finned fishes (Polypteridae) with implications for the evolution of body elongation, pelvic fin loss, and craniofacial morphology in Osteichthyes

    PubMed Central

    2010-01-01

    future comparative evolutionary, physiological, ecological, and genetic analyses. Indeed, ancestral reconstruction and geometric morphometric analyses revealed that the patterns of morphological evolution in Polypteridae are similar to those seen in other osteichthyans, thus implying the underlying genetic and developmental mechanisms responsible for those patterns were established early in the evolutionary history of Osteichthyes. We propose developmental and genetic mechanisms to be tested under the light of this new phylogenetic framework. PMID:20100320

  7. Revision of Metahaliotrema Yamaguti, 1953 (Monogenoidea: Dactylogyridae), with new and previously described species from the spotted scat Scatophagus argus (Linnaeus) (Perciformes: Scatophagidae) in Vietnam.

    PubMed

    Kritsky, Delane C; Nguyen, Ha Van; Ha, Ngo Duy; Heckmann, Richard A

    2016-05-01

    An emended diagnosis of Metahaliotrema Yamaguti, 1953 (Monogenoidea: Dactylogyridae) is provided based on specimens of six species collected from the spotted scat Scatophagus argus (Linnaeus) (Scatophagidae) in Vietnam: M. scatophagi Yamaguti, 1953 (type-species); M. cf. yamagutii Mizelle & Price, 1964; M. mizellei Venkatanarasaiah, 1981; M. kulkarnii Venkatanarasaiah, 1981; M. ypsilocleithrum n. sp.; and M. similis n. sp. Methaliotrema filamentosum Venkatanarasaiah, 1981 from the whipfin silver-biddy Gerres filamentosus Cuvier (Gerreidae) is included as the only other valid member of the genus. Metahaliotrema arii Yamaguti, 1953 from an ariid catfish is considered incertae sedis within the Dactylogyridae; and Metahaliotrema srivastavai Singh & Agarwal, 1994 from a bagrid catfish is transferred to Chauhanellus Bychowsky & Nagibina, 1969 as Chauhanellus srivastavai (Singh & Agarwal, 1994) n. comb. Metahaliotrema geminatohamula Pan, Ding & Zhang, 1995 from spotted scat in China is determined to be a junior subjective synonym of M. scatophagi. The two new species and M. scatophagi, M. mizellei, and M. kulkarnii are described or redescribed based on specimens from Vietnam.

  8. Temperature induced variation in oxygen consumption of juvenile and adult stage of the dog conch Laevistrombus canarium (Linnaeus 1758)

    NASA Astrophysics Data System (ADS)

    Hassan, Wan Nurul Husna Wan; Amin, S. M. Nurul; Ghaffar, Mazlan Abd; Cob, Zaidi Che

    2015-09-01

    Laevistrombus canarium Linnaeus, 1758 is one of the important edible sea snail within the western Johor Straits, Malaysia. In this study, the impact of temperature on oxygen consumption (MO2) of L. canarium based on their ontogenetic changes (juvenile and adult) was measured in the laboratory condition at 22.0, 26.0, 30.0 and 34.0°C. Measurement of MO2 were taken every 1 s for 60 min on 4.20 - 34.00 g dog conch using respirometry chamber. All experiments were carried out in static conditions in five replicates with one snail per chambers. The results of oxygen consumption showed that juvenile dog conch respired at the rate of 0.163 ml h-1 and adult respired at the rate of 0.119 ml h-1. Consequently, the oxygen consumption in juvenile and adult dog conch was expressed as a total energy spends. The results indicates that total energy spend for oxygen consumed (ml h-1) of L. canarium at different temperature regimes (22.0 to 34.0°C) slightly increased over time period (0.63 ± 0.12 to 3.24 ± 0.05 J h-1) respectively. This finding of the present study suggested L. canarium is well adapted for life in high temperature environment.

  9. Behavioural adaptations of two sympatric sandhoppers living on a mesotidal European Atlantic sandy beach

    NASA Astrophysics Data System (ADS)

    Bessa, Filipa; Marques, João Carlos; Scapini, Felicita

    2014-06-01

    Behavioural adaptations of supralittoral species on sandy beaches are expressed as responses to environmental changes and constitute a key factor in their survival and evolution. Two sympatric talitrid amphipods (Talitrus saltator and Britorchestia brito) from a mesotidal exposed sandy beach on the European Atlantic coast (Portugal) were compared as regards orientation and littoral zonation patterns under natural conditions. Orientation experiments were carried out during spring and summer 2011 and 2012 at Quiaios beach, a highly dynamic exposed sandy beach. Multiple regression models were fitted to the angular data and the environmental effects on orientation were investigated for each species. Both talitrids were shown to be well orientated towards the shoreline and finely adapted to the mesotidal environment but a different use of local cues and climatic features between the two species was apparent. T. saltator showed a lower precision in the orientation performance (with a bimodal distribution sea- and land-wards), with less dependence on the sun cues and higher dependence on climatic features. In addition, the zonation of T. saltator was across the land-sea axis during both seasons. For B. brito the landscape vision, sun visibility and the tidal range enhanced the orientation to the shoreline. On this mesotidal Atlantic beach, T. saltator appeared to have a more flexible orientation with respect to B. brito, which appeared to be more dependent on the conditions offered by the intertidal zone, a behaviour confirmed by its restricted zonation below the high tide mark. Consequently, T. saltator showed a more flexible behaviour that may be considered an important evolutionary adaptation to dynamic and mesotidal sandy beaches.

  10. Reduction in soil aggregation in response to dust emission processes

    NASA Astrophysics Data System (ADS)

    Swet, Nitzan; Katra, Itzhak

    2016-09-01

    Dust emission by aeolian (wind) soil erosion depends on the topsoil properties of the source area, especially on the nature of the aggregates where most dust particles are held. Although the key role of soil aggregates in dust emission, the response of soil aggregation to aeolian processes and its implications for dust emission remain unknown. This study focuses on aggregate size distribution (ASD) analyses before and after in-situ aeolian experiments in semiarid loess soils that are associated with dust emission. Wind tunnel simulations show that particulate matter (PM) emission and saltation rates depend on the initial ASD and shear velocity. Under all initial ASD conditions, the content of saltator-sized aggregates (63-250 μm) increased by 10-34% due to erosion of macro-aggregates (> 500 μm), resulting in a higher size ratio (SR) between the saltators and macro-aggregates following the aeolian erosion. The results revealed that the saltator production increases significantly for soils that are subjected to short-term (anthropogenic) disturbance of the topsoil. The findings highlight a decrease in soil aggregation for all initial ASD's in response to aeolian erosion, and consequently its influence on the dust emission potential. Changes in ASD should be considered as a key parameter in dust emission models of complex surfaces.

  11. Trace Metals in Noah's Ark Shells (Arca noae Linnaeus, 1758): Impact of Tourist Season and Human Health Risk.

    PubMed

    Ivanković, Dušica; Erk, Marijana; Župan, Ivan; Čulin, Jelena; Dragun, Zrinka; Bačić, Niko; Cindrić, Ana-Marija

    2016-10-01

    Commercially important bivalve Noah's Ark shell (Arca noae Linnaeus, 1758) represents a high-quality seafood product, but the data on levels of metal contaminants that could pose a human health risk and also on some essential elements that are important for health protection are lacking. This study examined the concentrations of Cd, Pb, Cr, Ni, Cu, Co, and Zn in the soft tissue of A. noae from harvesting area in the central Adriatic Sea, to survey whether heavy metals are within the acceptable limits for public health and whether tourism could have an impact on them. The concentrations of analysed metals varied for Cd: 0.15-0.74, Pb: 0.06-0.26, Cr: 0.11-0.34, Ni: 0.09-0.22, Cu: 0.65-1.95, Co: 0.04-0.09, and Zn: 18.3-74.7 mg/kg wet weight. These levels were lower than the permissible limits for safe consummation of seafood, and only for Cd, some precautions should be taken into account if older shellfish were consumed. Increase of Cd, Cr, and Cu in shell tissue was observed during the tourist season at the site closest to the marine traffic routes, indicating that metal levels in shellfish tissue should be monitored especially carefully during the peak tourist season to prevent eventual toxic effects due to increased intake of metals, specifically of Cd.

  12. Elemental profiling of Noah's Ark shell (Arca noae, Linnaeus, 1758) by plasma optical spectrometry and chemometric tools.

    PubMed

    Kobelja, Kristina; Nemet, Ivan; Župan, Ivan; Čulin, Jelena; Rončević, Sanda

    2016-12-01

    Determination of metal content in biominerals provides essential information with respect to relations between biomineralization processes and environmental status. Mussels are species that have a great potential as bio-marker species and therefore, they are in the focus of numerous biomineralization and ecological studies. In this study, elemental profile of mussel shell of Noah's Ark (Arca noe, Linnaeus, 1758), which inhabit eastern Adriatic Sea was obtained by determination of seventeen elements content using inductively coupled plasma optical emission spectrometry (ICP-OES). Shell samples were collected from marine protected area and from marine shipping route in eastern Adriatic Sea. The accuracy of applied analytical procedure based on microwave decomposition of shell samples was tested by use of reference materials of limestone and by matrix-matched standards. By aid of chemometric methods, the elemental profile along with variability of elements content of shell was obtained. The impact of different environment on elements content was established by use of multivariate statistical PCA method. Discernment between two groups of samples was manifested. Among results of main, minor and trace elements content, the last one which denoted to Cd, Co, Cu, Pb, and Mn was expressed as principal distinctive feature of shell samples collected from different sampling sites. Elemental profiling of mussel shell Noah's Ark provides novel insight in species status as well as in environmental status on the observed locations. Copyright © 2016 Elsevier GmbH. All rights reserved.

  13. Geographic extent and chronology of the invasion of non-native lionfish (Pterois volitans [Linnaeus 1758] and P. miles [Bennett 1828]) in the Western North Atlantic and Caribbean Sea

    USGS Publications Warehouse

    Schofield, Pamela J.

    2009-01-01

    The Indo-Pacific lionfishes (Pterois volitans [Linnaeus 1758] and P. miles [Bennett 1828]: Family Scorpaenidae) are the first non-native marine fishes to establish in the Western North Atlantic. The chronology of the invasion is reported here using records from the US Geological Survey's Nonindigenous Aquatic Species database. Currently, lionfish are established off the Atlantic coast of the USA from the Florida Keys to Cape Hatteras (North Carolina), the Great Antilles, Bermuda, Bahamas, Cayman Islands and Turks and Caicos. The species have been reported from only one island in the Lesser Antilles (St. Croix), but it is not yet established there. Lionfish are established in Mexico, Honduras and Costa Rica. Reports have come from the Gulf of Mexico (Florida), Belize, Panama and Colombia; although lionfish are not considered established in these localities at this time (August 2009), invasion is likely imminent.

  14. Microdunes and other aeolian bedforms on Venus - Wind Tunnel simulations

    NASA Technical Reports Server (NTRS)

    Greeley, R.; Marshall, J. R.; Leach, R. N.

    1984-01-01

    The development of aeolian bedforms in the simulated Venusian environment has been experimentally studied in the Venus Wind Tunnel. It is found that the development of specific bedforms, including ripples, dunes, and 'waves', as well as their geometry, are controlled by a combination of factors including particle size, wind speed, and atmospheric density. Microdunes are formed which are analogous to full-size terrestrial dunes and are characterized by the development of slip faces, internal cross-bedding, a low ratio of saltation path length to dune length, and a lack of particle-size sorting. They begin to develop at wind speeds just above saltation threshold and evolve into waves at higher velocities. At wind speeds of about 1.5 m/sec and higher, the bed is flat and featureless. This evolution is explained by a model based on the interaction of alternating zones of erosion and deposition and particle saltation distances.

  15. Microdunes and Other Aeolian Bedforms on Venus: Wind Tunnel Simulations

    NASA Technical Reports Server (NTRS)

    Greeley, R.; Marshall, J. R.; Leach, R. N.

    1985-01-01

    The development of aeolian bedforms in the simulated Venusian environment has been experimentally studied in the Venus Wind tunnel. It is found that the development of specific bedforms, including ripples, dunes, and waves, as well as their geometry, are controlled by a combination of factors including particle size, wind speed, and atmospheric density. Microdunes are formed which are analogous to full-size terrestrial dunes and are characterized by the development of slip faces, internal cross-bedding, a low ratio of saltation path length to dune length, and a lack of particle-size sorting. They begin to develop at wind speeds just above saltation threshold and evolve into waves at higher velocities. At wind speeds of about 1.5 m/sec and higher, the bed is flat and featureless. This evolution is explained by a model based on the interaction of alternating zones of erosion and deposition and particle saltation distances.

  16. Aeolian sand transport and aeolian deposits on Venus: A review

    NASA Astrophysics Data System (ADS)

    Kreslavsly, Mikhail A.; Bondarenko, Nataliya V.

    2017-06-01

    We review the current state of knowledge about aeolian sand transport and aeolian bedforms on planet Venus. This knowledge is limited by lack of observational data. Among the four planetary bodies of the Solar System with sufficient atmospheres in contact with solid surfaces, Venus has the densest atmosphere; the conditions there are transitional between those for terrestrial subaerial and subaqueous transport. The dense atmosphere causes low saltation threshold and short characteristic saltation length, and short scale length of the incipient dunes. A few lines of evidence indicate that the typical wind speeds exceed the saltation threshold; therefore, sand transport would be pervasive, if sand capable of saltation is available. Sand production on Venus is probably much slower than on the Earth; the major terrestrial sand sinks are also absent, however, lithification of sand through sintering is expected to be effective under Venus' conditions. Active transport is not detectable with the data available. Aeolian bedforms (transverse dunes) resolved in the currently available radar images occupy a tiny area on the planet; however, indirect observations suggest that small-scale unresolved aeolian bedforms are ubiquitous. Aeolian transport is probably limited by sand lithification causing shortage of saltation-capable material. Large impact events likely cause regional short-term spikes in aeolian transport by supplying a large amount of sand-size particles, as well as disintegration and activation of older indurated sand deposits. The data available are insufficient to understand whether the global aeolian sand transport occurs or not. More robust knowledge about aeolian transport on Venus is essential for future scientific exploration of the planet, in particular, for implementation and interpretation of geochemical studies of surface materials. High-resolution orbital radar imaging with local to regional coverage and desirable interferometric capabilities is the

  17. On mysterious occurrence of butterflies in the genus Delias at Jinmen Islands, with clarification on the nomenclature of D. pasithoe (Linnaeus, 1767) and D. acalis (Godart, 1819) in southern China.

    PubMed

    Hsu, Yu-Feng; Huang, Hang-Chi; Lu, Chen-Chih

    2017-06-11

    In recent years, a considerable number of pierid butterflies of the genus Delias have been found from Jinmen Islands, where no available hostplants grow, rendering a proof of cross sea water migration of these butterflies. It is suggested here that these butterflies come from nearby continent of eastern China, visiting the islands for nectar acquisition in seasons when nectar is in short supply because they mostly show up in autumn months. Samples obtained during the survey contained two species, namely Delias pasithoe (Linnaeus, 1767) and Delias acalis (Godart, 1819). Subspecific names applied to both species in eastern China appear to involve nomenclatural problems, with erroneous usage in recent literature.

  18. Repellency and Larvicidal Activity of Essential oils from Xylopia laevigata, Xylopia frutescens, Lippia pedunculosa, and Their Individual Compounds against Aedes aegypti Linnaeus.

    PubMed

    Nascimento, A M D; Maia, T D S; Soares, T E S; Menezes, L R A; Scher, R; Costa, E V; Cavalcanti, S C H; La Corte, R

    2017-04-01

    In order to find new alternatives for vector control and personal protection, we evaluated the larvicidal and repellent activity of essentials oils from plants found in the Northeast of Brazil against Aedes aegypti Linnaeus mosquitoes. The plants tested include Xylopia laevigata, Xylopia frutescens, and Lippia pedunculosa and their major compounds, piperitenone oxide, and (R)-limonene. The essential oil of L. pedunculosa and its major volatile compounds were shown to be toxic for Ae. aegypti larvae with a LC 50 lower than 60 ppm. The essential oil of plants from the Xylopia genus, on the other hand, showed no activity against Ae. aegypti, proving to be toxic to mosquito larvae only when concentrations were higher than 1000 ppm. All plants tested provided some degree of protection against mosquitoes landing, but only the essential oil of L. pedunculosa and the volatile compound piperitenone oxide suppressed 100% of mosquitoes landing on human skin, in concentrations lower than 1%. Among the plants studied, the essential oil of L. pedunculosa and its volatiles compounds have shown the potential for the development of safe alternative for mosquito larvae control and protection against Ae. aegypti mosquito bites.

  19. Threshold for sand mobility on Mars calibrated from seasonal variations of sand flux.

    PubMed

    Ayoub, F; Avouac, J-P; Newman, C E; Richardson, M I; Lucas, A; Leprince, S; Bridges, N T

    2014-09-30

    Coupling between surface winds and saltation is a fundamental factor governing geological activity and climate on Mars. Saltation of sand is crucial for both erosion of the surface and dust lifting into the atmosphere. Wind tunnel experiments along with measurements from surface meteorology stations and modelling of wind speeds suggest that winds should only rarely move sand on Mars. However, evidence for currently active dune migration has recently accumulated. Crucially, the frequency of sand-moving events and the implied threshold wind stresses for saltation have remained unknown. Here we present detailed measurements of Nili Patera dune field based on High Resolution Imaging Science Experiment images, demonstrating that sand motion occurs daily throughout much of the year and that the resulting sand flux is strongly seasonal. Analysis of the seasonal sand flux variation suggests an effective threshold for sand motion for application to large-scale model wind fields (1-100 km scale) of τ(s)=0.01±0.0015 N m(-2).

  20. Influence of levamisole and Freund's adjuvant on mouse immunisation with antigens of adults of the liver fluke Fasciola hepatica Linnaeus, 1758.

    PubMed

    Gutierrez-Sanchez, Maria de Los Angeles; Luna-Herrera, Julieta; Trejo-Castro, Lauro; Montenegro-Cristino, Natividad; Almanza-Gonzalez, Alfredo; Escobar-Gutierrez, Alejandro; de la Rosa-Arana, Jorge Luis

    2015-08-28

    We have studied the influence of both levamisole (AL) and Freund's adjuvant (AF) on the immunisation of mice with the secretory antigens of adults of the liver fluke Fasciola hepatica Linnaeus, 1758. Total IgG antibodies were detected in all groups where the F. hepatica antigen was administered, been levels of IgG1 increased respect to IgG2a antibodies. During immunisation, IL-4 and IFN-γ were only detected in AL and AF groups, but after infection, IL-4 boosted in all groups. IFN-γ increased two fold in AF and AL groups compared to the saline solution (AS) group. Worm recovering was of 32-35% in groups administered without antigen whereas in AS, AL and AF groups recovering was of 25%, 12% and 8%, respectively. Macroscopical lesions in the liver were scarce in AL and AF groups. Our data suggest that immunisation of mice with antigens of F. hepatica enhances the immune response avoiding both liver damage and worm establishment after challenge infection. The murine model of fasciolosis has appeared to be useful to elucidate the mechanism by which the parasite modulates immune responses toward a Th2 type but also the development of Th1 type-inducing vaccines.

  1. Fresh and Dry Mass Estimates of Hermetia illucens (Linnaeus, 1758) (Diptera: Stratiomyidae) Larvae Associated with Swine Decomposition in Urban Area of Central Amazonia.

    PubMed

    Barros, L M; Martins, R T; Ferreira-Keppler, R L; Gutjahr, A L N

    2017-08-04

    Information on biomass is substantial for calculating growth rates and may be employed in the medicolegal and economic importance of Hermetia illucens (Linnaeus, 1758). Although biomass is essential to understanding many ecological processes, it is not easily measured. Biomass may be determined by directly weighing or indirectly through regression models of fresh/dry mass versus body dimensions. In this study, we evaluated the association between morphometry and fresh/dry mass of immature H. illucens using linear, exponential, and power regression models. We measured width and length of the cephalic capsule, overall body length, and width of the largest abdominal segment of 280 larvae. Overall body length and width of the largest abdominal segment were the best predictors for biomass. Exponential models best fitted body dimensions and biomass (both fresh and dry), followed by power and linear models. In all models, fresh and dry biomass were strongly correlated (>75%). Values estimated by the models did not differ from observed ones, and prediction power varied from 27 to 79%. Accordingly, the correspondence between biomass and body dimensions should facilitate and motivate the development of applied studies involving H. illucens in the Amazon region.

  2. Species Profiles: Life Histories and Environmental Requirements of Coastal Vertebrates and Invertebrates Pacific Ocean Region. Report 3. Amphidromous Macrofauna of Hawaiian Island Streams

    DTIC Science & Technology

    1990-08-01

    history pat- Chordata, Class Osteichthyes; Mol- terns occur in many areas of partic- lusca, Class Gastropoda ; and ular concern to agencies of the Arthropoda...Endemic (Randall, 1840) Phylum Mollusca Class Gastropoda Order Pulmonata Neritina granosa hihiwai Endemic Sowerby, 1825 wi Neritina vespertina hapawai...pp. Thesis. Zoology Department, 24 Haynes, A. 1988. Notes on the Park Resources Studies Unit, stream neritids ( Gastropoda ; Department of Botany

  3. Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (South Florida). WHITE MULLET.

    DTIC Science & Technology

    1985-05-01

    of the head Class ............ .Osteichthyes length. Order .... .......... Perciformes - Family .... ........... Mugilidae REASON FOR INCLUSION IN...SERIES Geographic range: Atlantic and East- The white mullet, the second most ern Pacific; in the Western Atlantic common species of the family Mugilidae ...del ciclo de Rep. 55(34):1-15. vida de MugiI curema Valenciennes in Cuviere- Valenciennes, 1836 Moore, R. H. 1973. Energetic re- ilisces: Mugilidae

  4. Infant head circumference growth is saltatory and coupled to length growth.

    PubMed

    Lampl, Michelle; Johnson, Michael L

    2011-05-01

    Rapid growth rates of head circumference and body size during infancy have been reported to predict developmental pathologies that emerge during childhood. This study investigated whether growth in head circumference was concordant with growth in body length. Forty infants (16 males) were followed between the ages of 2 days and 21 months for durations ranging from 4 to 21 months (2616 measurements). Longitudinal anthropometric measurements were assessed weekly (n=12), semi-weekly (n=24) and daily (n=4) during home visits. Individual head circumference growth was investigated for the presence of saltatory patterns. Coincident analysis tested the null hypothesis that head growth was randomly coupled to length growth. Head circumference growth during infancy is saltatory (p<0.05), characterized by median increments of 0.20 cm (95% confidence interval, 0.10-0.30 cm) in 24-h, separated by intervals of no growth ranging from 1 to 21 days. Daily assessments identified that head growth saltations were coupled to length growth saltations within a median time frame of 2 days (interquartile 0-4, range 1-8 days). Assessed at semi-weekly and weekly intervals, an average 82% (SD 0.13) of head growth saltations was non-randomly concordant with length growth (p≤0.006). Normal infant head circumference grows by intermittent, episodic saltations that are temporally coupled to growth in total body length by a process of integrated physiology that remains to be described. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Molecular confirmation of Trichomonas gallinae and other parabasalids from Brazil using the 5.8S and ITS-1 rRNA regions.

    PubMed

    Ecco, Roselene; Preis, Ingred S; Vilela, Daniel A R; Luppi, Marcela M; Malta, Marcelo C C; Beckstead, Robert B; Stimmelmayr, Raphaela; Stimmelmayer, Raphaela; Gerhold, Richard W

    2012-11-23

    Clinical, gross, and histopathology lesions and molecular characterization of Trichomonas spp. infection were described in two striped owls (Asio (Rhinoptynx) clamator), one American kestrel (Falco sparverius), two green-winged saltators (Saltator similis), and in a toco toucan (Ramphastos toco) from Brazil. These birds presented clinical signs including emaciation, ruffled feathers, abundant salivation and open mouth breathing presumably due to abundant caseous material. Gross lesions were characterized by multifocal yellow friable plaques on the surface of the tongue, pharynx and/or caseous masses partially occluding the laryngeal entrance. In the owls, the caseous material extended into the mandibular muscles and invaded the sinuses of the skull. Histopathologically, marked necrotic and inflammatory lesions were associated with numerous round to oval, pale eosinophilic structures (6-10μm) with basophilic nuclei, consistent with trichomonads. Organisms similar to those described above also were found in the liver of the two green-winged saltators. To the authors' knowledge, this is the first report of trichomonosis in a striped owl and a toco toucan. Sequence analysis of the Trichomonas spp. internal transcribed spacer 1 (ITS-1) region and partial 5.8S of the ribosomal RNA (rRNA) disclosed significant genetic diversity. Two sequences had 100% identity to Trichomonas gallinae, whereas two sequences had a 99% and 92% identity to a Trichomonas vaginalis-like sequence, respectively. One sequence (green-winged saltator 502-08) had a 100% identity to a newly recognized genus Simplicomonas. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. An improved numerical model suggests potential differences of wind-blown sand between on Earth and Mars

    NASA Astrophysics Data System (ADS)

    Bo, T. L.; Fu, L. T.; Liu, L.; Zheng, X. J.

    2017-06-01

    The studies on wind-blown sand are crucial for understanding the change of climate and landscape on Mars. However, the disadvantages of the saltation models may result in unreliable predictions. In this paper, the saltation model has been improved from two main aspects, the aerodynamic surface roughness and the lift-off parameters. The aerodynamic surface roughness is expressed as function of particle size, wind strength, air density, and air dynamic viscosity. The lift-off parameters are improved through including the dependence of restitution coefficient on incident parameters and the correlation between saltating speed and angle. The improved model proved to be capable of reproducing the observed data well in both stable stage and evolution process. The modeling of wind-blown sand is promoted by all improved aspects, and the dependence of restitution coefficient on incident parameters could not be ignored. The constant restitution coefficient and uncorrelated lift-off parameter distributions would lead to both the overestimation of the sand transport rate and apparent surface roughness and the delay of evolution process. The distribution of lift-off speed and the evolution of lift-off parameters on Mars are found to be different from those on Earth. This may thus suggest that it is inappropriate to predict the evolution of wind-blown sand by using the lift-off velocity obtained in steady state saltation. And it also may be problematic to predict the wind-blown sand on Mars through applying the lift-off velocity obtained upon terrestrial conditions directly.

  7. Variation in Aedes aegypti (Linnaeus) (Diptera, Culicidae) infestation in artificial containers in Caxias, state of Maranhão, Brazil.

    PubMed

    Soares-da-Silva, Joelma; Ibiapina, Sebastiana Silva; Bezerra, Juliana Maria Trindade; Tadei, Wanderli Pedro; Pinheiro, Valéria Cristina Soares

    2012-01-01

    Dengue is a serious public health problem worldwide, with cases reported annually in tropical and subtropical regions. Aedes aegypti (Linnaeus, 1762), the main vector of dengue, is a domiciliary species with high dispersal and survival capacities and can use various artificial containers as breeding sites. We assessed potential container breeding sites of A. aegypti in the municipality of Caxias, Maranhão, Brazil. In the initial phase, we analyzed 900 properties in 3 neighborhoods during the dry and rainy seasons (August-October 2005 and February-April 2006, respectively). During the second sampling period, September 2006-August 2007, we used 5 assessment cycles for 300 properties in a single neighborhood. During the dry and rainy seasons, water-storage containers comprised 55.7% (n = 1,970) and 48.5% (n = 1,836) of the total containers inspected, and showed the highest productivity of immature A. aegypti; we found 23.7 and 106.1 individuals/container, respectively, in peridomicile sites. In intradomicile sites, water-storage containers were also the most important breeding sites with 86.4% (n = 973) and 85.6% (n = 900) of all containers and a mean of 7.9 and 108.3 individuals/container in the dry and rainy seaso-October 2006 (1,342). The highest number of positives (70) was recorded in May, mostly (94%) in storage containers. Storage containers are the principal and most productive A. aegypti breeding sites and are a major contributing factor to the maintenance of this vector in Caxias.

  8. Modeling suitable habitat of invasive red lionfish Pterois volitans (Linnaeus, 1758) in North and South America’s coastal waters

    USGS Publications Warehouse

    Evangelista, Paul H.; Young, Nicholas E.; Schofield, Pamela J.; Jarnevich, Catherine S.

    2016-01-01

    We used two common correlative species-distribution models to predict suitable habitat of invasive red lionfish Pterois volitans (Linnaeus, 1758) in the western Atlantic and eastern Pacific Oceans. The Generalized Linear Model (GLM) and the Maximum Entropy (Maxent) model were applied using the Software for Assisted Habitat Modeling. We compared models developed using native occurrences, using non-native occurrences, and using both native and non-native occurrences. Models were trained using occurrence data collected before 2010 and evaluated with occurrence data collected from the invaded range during or after 2010. We considered a total of 22 marine environmental variables. Models built with non-native only or both native and non-native occurrence data outperformed those that used only native occurrences. Evaluation metrics based on the independent test data were highest for models that used both native and non-native occurrences. Bathymetry was the strongest environmental predictor for all models and showed increasing suitability as ocean floor depth decreased, with salinity ranking the second strongest predictor for models that used native and both native and non-native occurrences, indicating low habitat suitability for salinities <30. Our model results also suggest that red lionfish could continue to invade southern latitudes in the western Atlantic Ocean and may establish localized populations in the eastern Pacific Ocean. We reiterate the importance in the choice of the training data source (native, non-native, or native/non-native) used to develop correlative species distribution models for invasive species.

  9. 7 CFR 360.200 - Designation of noxious weeds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... mantegazzianum Sommier & Levier (giant hogweed) Imperata brasiliensis Trinius (Brazilian satintail) Imperata cylindrica (Linnaeus) Palisot de Beauvois (cogongrass) Inula britannica Linnaeus (British elecampane, British...

  10. 7 CFR 360.200 - Designation of noxious weeds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... mantegazzianum Sommier & Levier (giant hogweed) Imperata brasiliensis Trinius (Brazilian satintail) Imperata cylindrica (Linnaeus) Palisot de Beauvois (cogongrass) Inula britannica Linnaeus (British elecampane, British...

  11. 7 CFR 360.200 - Designation of noxious weeds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... mantegazzianum Sommier & Levier (giant hogweed) Imperata brasiliensis Trinius (Brazilian satintail) Imperata cylindrica (Linnaeus) Palisot de Beauvois (cogongrass) Inula britannica Linnaeus (British elecampane, British...

  12. Hypoosmotic stress in the mussel Perna perna (Linnaeus, 1758): Is ecological history a determinant for organismal responses?

    NASA Astrophysics Data System (ADS)

    Rola, Regina Coimbra; Souza, Marta Marques; Sandrini, Juliana Zomer

    2017-04-01

    Ecological history of organisms may be related to different responses and adaptations to stressors. This study aims to evaluate whether marine brown mussels (Perna perna Linnaeus, 1758) collected from sites with distinct histories of fluctuations in abiotic parameters, including salinity, respond differently to hypoosmotic stress. Mussels were collected at different sites (a marine site, with no history of salinity variation, and an estuarine site, with usual salinity variations) and exposed in laboratory for 14 days to hypoosmotic stress (salinities 25 and 20). It was observed that mussels collected at the marine site showed increased oxygen consumption (VO2), reduced haemolymph osmolality and concentrations of Na+, Cl-, and K+; increased levels of ninhydrin-positive substances in the haemolymph, and no changes in gill Na+/K+-ATPase activity, as expected for osmoconforming organisms. For animals collected at the estuarine site, except for VO2, this same pattern was only observed on day 1 of hypoosmotic stress. Unexpectedly, on days 4 and 14, VO2 decreased, the osmolality and ionic concentration returned to near baseline values, and mussels gill Na+/K+-ATPase activity increased at day 4. This long-term response detected for estuarine mussels is similar to that observed for osmoregulating organisms, which is very unexpected for marine bivalves. Despite being novel in the relevant literature, these results suggest that in some situations mussels could adopt osmoregulating behavior, such as increasing Na+/K+-ATPase activity and thereby probably reducing water circulating inside valves. In conclusion, these results indicate that ecological history, shown here by differences in organismal origin, influence physiological parameters of mussels in response to a stressful situation.

  13. A new turbulence-based model for sand transport

    NASA Astrophysics Data System (ADS)

    Mayaud, Jerome; Wiggs, Giles; Bailey, Richard

    2016-04-01

    Knowledge of the changing rate of sediment flux in space and time is essential for quantifying surface erosion and deposition in desert landscapes. While many aeolian studies have relied on time-averaged parameters such as wind velocity (U) and wind shear velocity (u*) to determine sediment flux, there is increasing evidence that high-frequency turbulence is an important driving force behind the entrainment and transport of sand. However, turbulence has yet to be incorporated into a functional sand transport model that can be used for predictive purposes. In this study we present a new transport model (the 'turbulence model') that accounts for high-frequency variations in the horizontal (u) and vertical (w) components of wind flow. The turbulence model is fitted to wind velocity and sediment transport data from a field experiment undertaken in Namibia's Skeleton Coast National Park, and its performance at three temporal resolutions (10 Hz, 1 Hz, 1 min) is compared to two existing models that rely on time-averaged wind velocity data (Radok, 1977; Dong et al., 2003). The validity of the three models is analysed under a variety of saltation conditions, using a 2-hour (1 Hz measurement resolution) dataset from the Skeleton Coast and a 5-hour (1 min measurement resolution) dataset from the southwestern Kalahari Desert. The turbulence model is shown to outperform the Radok and Dong models when predicting total saltation count over the three experimental periods. For all temporal resolutions presented in this study (10 Hz-10 min), the turbulence model predicted total saltation count to within at least 0.34%, whereas the Radok and Dong models over- or underestimated total count by up to 5.50% and 20.53% respectively. The strong performance of the turbulence model can be attributed to a lag in mass flux response built into its formulation, which can be adapted depending on the temporal resolution of investigation. This accounts for the inherent lag within the physical

  14. Shelter Index and a simple wind speed parameter to characterize vegetation control of sand transport threshold and Flu

    NASA Astrophysics Data System (ADS)

    Gillies, J. A.; Nield, J. M.; Nickling, W. G.; Furtak-Cole, E.

    2014-12-01

    Wind erosion and dust emissions occur in many dryland environments from a range of surfaces with different types and amounts of vegetation. Understanding how vegetation modulates these processes remains a research challenge. Here we present results from a study that examines the relationship between an index of shelter (SI=distance from a point to the nearest upwind vegetation/vegetation height) and particle threshold expressed as the ratio of wind speed measured at 0.45 times the mean plant height divided by the wind speed at 17 m when saltation commences, and saltation flux. The results are used to evaluate SI as a parameter to characterize the influence of vegetation on local winds and sediment transport conditions. Wind speed, wind direction, saltation activity and point saltation flux were measured at 35 locations in defined test areas (~13,000 m2) in two vegetation communities: mature streets of mesquite covered nebkhas and incipient nebkhas dominated by low mesquite plants. Measurement positions represent the most open areas, and hence those places most susceptible to wind erosion among the vegetation elements. Shelter index was calculated for each measurement position for each 10° wind direction bin using digital elevation models for each site acquired using terrestrial laser scanning. SI can show the susceptibility to wind erosion at different time scales, i.e., event, seasonal, or annual, but in a supply-limited system it can fail to define actual flux amounts due to a lack of knowledge of the distribution of sediment across the surface of interest with respect to the patterns of SI.

  15. Changes in the nesting populations of colonial waterbirds in Jamaica Bay Wildlife Refuge, New York, 1974-1998

    USGS Publications Warehouse

    Brown, K.M.; Tims, J.L.; Erwin, R.M.; Richmond, M.E.

    2001-01-01

    The Jamaica Bay Wildlife Refuge (JBWR) represents the largest protected area for over 300 species of migratory and resident birds on Long Island (LI), New York, and occupies a key position along the Atlantic flyway. We identified changes in nesting populations for 18 species of colonial waterbirds in JBWR and on LI, during 1974 - 1998, to provide a basis for future wildlife management decisions in JBWR and also at nearby John F. Kennedy International Airport. None of the populations was stable over the past 25 years in JBWR or on LI. Some populations in JBWR increased (Laughing Gull L. atricilla Linnaeus, Great Black-backed Gull L. marinus Linnaeus, Forster's Tern Sterna forsteri Nuttall) while others decreased (Herring Gull Larus argentatus Coues, Snowy Egret Egretta thula Molina), but only Cattle Egrets (Bubulcus ibis Linnaeus) have disappeared from the refuge. Common Tern (S. hitundo Linnaeus), Least Tern (S. antillarum Lesson), Roseate Tern (S. dougallii Montagu), Black Skimmer (Rynchops niger Linnaeus), Black-crowned Night Heron (Nycticorax nycticorax Linnaeus) and Great Egret (Ardea alba Linnaeus) populations all increased on LI over the sampling period although the Common Tern colonies in JBWR have been declining since 1986. The continued protection of the colony sites, particularly saltmarsh islands, in JBWR will be important to the conservation efforts of many colonial waterbird populations on Long Island. The JBWR colonies may serve as a source of emigrants to other Long Island colonies, and in some cases, act as a 'sink' for birds immigrating from New Jersey and elsewhere.

  16. Size-Selective Modes of Aeolian Transport on Earth and Mars

    NASA Astrophysics Data System (ADS)

    Swann, C.; Ewing, R. C.; Sherman, D. J.; McLean, C. J.

    2016-12-01

    Aeolian sand transport is a dominant driver of surface change and dust emission on Mars. Estimates of aeolian sand transport on Earth and Mars rely on terrestrial transport models that do not differentiate between transport modes (e.g., creep vs. saltation), which limits estimates of the critical threshold for transport and the total sand flux during a transport event. A gap remains in understanding how the different modes contribute to the total sand flux. Experiments conducted at the MARtian Surface WInd Tunnel separated modes of transport for uniform and mixed grain size surfaces at Earth and Martian atmospheric pressures. Crushed walnut shells with a density of 1.0 gm/cm3 were used. Experiments resolved grain size distributions for creeping and saltating grains over 3 uniform surfaces, U1, U2, and U3, with median grain sizes of 308 µm, 721 µm, and 1294 µm, and a mixed grain size surface, M1, with median grain sizes of 519 µm. A mesh trap located 5 cm above the test bed and a surface creep trap were deployed to capture particles moving as saltation and creep. Grains that entered the creep trap at angles ≥ 75° were categorized as moving in creep mode only. Only U1 and M1 surfaces captured enough surface creep at both Earth and Mars pressure for statistically significant grain size analysis. Our experiments show that size selective transport differs between Earth and Mars conditions. The median grain size of particles moving in creep for both uniform and mixed surfaces are larger under Earth conditions. (U1Earth = 385 µm vs. U1Mars = 355 µm; M1Earth = 762 vs. M1Mars = 697 µm ). However, particles moving in saltation were larger under Mars conditions (U1Earth = 282 µm; U1Mars = 309 µm; M1Earth = 347 µm; M1Mars = 454 µm ). Similar to terrestrial experiments, the median size of surface creep is larger than the median grain size of saltation. Median sizes of U1, U2, U3 at Mars conditions for creep was 355 µm, 774 µm and 1574 µm. Saltation at Mars

  17. Induction of gynogenetic and androgenetic haploid and doubled haploid development in the brown trout (Salmo trutta Linnaeus 1758).

    PubMed

    Michalik, O; Dobosz, S; Zalewski, T; Sapota, M; Ocalewicz, K

    2015-04-01

    Gynogenetic and androgenetic brown trout (Salmo trutta Linnaeus 1758) haploids (Hs) and doubled haploids (DHs) were produced in the present research. Haploid development was induced by radiation-induced genetic inactivation of spermatozoa (gynogenesis) or eggs (androgenesis) before insemination. To provide DHs, gynogenetic and androgenetic haploid zygotes were subjected to the high pressure shock to suppress the first mitotic cleavage. Among haploids, gynogenetic embryos were showing lower mortality when compared to the androgenetic embryos; however, most of them die before the first feeding stage. Gynogenetic doubled haploids provided in the course of the brown trout eggs activation performed by homologous and heterologous sperm (rainbow trout) were developing equally showing hatching rates of 14.76 ± 2.4% and 16.14 ± 2.90% and the survival rates at the first feeding stage of 10.48 ± 3.48% and 12.78 ± 2.18%, respectively. Significantly, lower survival rate was observed among androgenetic progenies from the diploid groups with only few specimens that survived to the first feeding stage. Cytogenetic survey showed that among embryos from the diploid variants of the research, only gynogenetic individuals possessed doubled sets of chromosomes. Thus, it is reasonable to assume that radiation employed for the genetic inactivation of the brown trout eggs misaligned mechanism responsible for the cell divisions and might have delayed or even arrested the first mitotic cleavage in the androgenetic brown trout zygotes. Moreover, protocol for the radiation-induced inactivation of the paternal and maternal genome should be adjusted as some of the cytogenetically surveyed gynogenetic and androgenetic embryos exhibited fragments of the irradiated chromosomes. © 2015 Blackwell Verlag GmbH.

  18. Morphological, molecular and developmental characterization of the thelastomatid nematode Thelastoma bulhoesi (de Magalhães, 1900) (Oxyuridomorpha: Thelastomatidae) parasite of Periplaneta americana (Linnaeus, 1758) (Blattodea: Blattidae) in Japan.

    PubMed

    Ozawa, Sota; Morffe, Jans; Vicente, Cláudia S L; Ikeda, Kenji; Shinya, Ryoji; Hasegawa, Koichi

    2016-03-01

    The American cockroach Periplaneta americana (Linnaeus, 1758) (Blattodea: Blattidae) has been spreading worldwide by commerce and has successfully adjusted to living with humans. There are many reports of thelastomatid parasitic nematode isolated from P. americana in many countries including USA, Canada, India, Argentina, Bulgaria, but not in Japan. We have investigated the parasitic nematodes in P. americana lab strain and field-captured individuals in Japan and found that Thelastoma bulhoesi (de Magalhães, 1900) (Oxyuridomorpha: Thelastomatidae) parasitizes with high infection rates. We described morphological, molecular, and developmental characters of the parasitic nematode because such information was missing despite it has been discovered more than one hundred years ago. We described morphometrics with DIC microscopy and fine structure of male and female adult with SEM observation. We also reveal the embryonic and postembryonic development of this nematode. This is the first report of a thelastomatid nematode isolated from American cockroach in Japan, and the data showed here is also very useful and fundamental for further analysis of the cockroach and parasite relations.

  19. Effects of supplemental coated or crystalline methionine in low-fishmeal diet on the growth performance and body composition of juvenile cobia Rachycentron canadum (Linnaeus)

    NASA Astrophysics Data System (ADS)

    Chi, Shuyan; Tan, Beiping; Dong, Xiaohui; Yang, Qihui; Liu, Hongyu

    2014-11-01

    We evaluated the effects of supplemental coated and crystalline methionine (Met) on the growth performance and feed utilization of juvenile cobia ( Rachycentron canadum Linnaeus) in a 60-d feeding trial. Fish groups were fed one of six isonitrogenous and isolipidic diets: 1) fishmeal control; 2) un-supplemented experimental (low-fish-meal diet deficient in Met); or 3) one of four Met diets supplemented with crystalline L-Met, cellulose-acetate-phthalate coated L-Met, acrylic-resin coated L-Met, or tripalmitin-polyvinyl alcohol coated L-Met. The test diets were fed to triplicate groups of cobia (initial body weight 5.40±0.07 g) twice a day. The weight gain and specific growth rate of the fish fed the RES diet were highest among the Met-supplemented groups and were 23.64% and 7.99%, respectively, higher than those of the fish fed with the un-supplemented experimental diet ( P<0.05). The protein efficiency ratio of the fish fed the MET diet was significantly higher than that of the fish fed the un-supplemented experimental diet and the fish in the other methionine supplementation groups ( P<0.05). Our results suggest that supplementation of crystalline Met in low-fish-meal diets promotes the growth performance of juvenile cobia.

  20. Aeolian Sand Transport with Collisional Suspension

    NASA Technical Reports Server (NTRS)

    Jenkins, James T.; Pasini, Jose Miguel; Valance, Alexandre

    2004-01-01

    Aeolian transport is an important mechanism for the transport of sand on Earth and on Mars. Dust and sand storms are common occurrences on Mars and windblown sand is responsible for many of the observed surface features, such as dune fields. A better understanding of Aeolian transport could also lead to improvements in pneumatic conveying of materials to be mined for life support on the surface of the Moon and Mars. The usual view of aeolian sand transport is that for mild winds, saltation is the dominant mechanism, with particles in the bed being dislodged by the impact of other saltating particles, but without in-flight collisions. As the wind becomes stronger, turbulent suspension keeps the particles in the air, allowing much longer trajectories, with the corresponding increase in transport rate. We show here that an important regime exists between these two extremes: for strong winds, but before turbulent suspension becomes dominant, there is a regime in which in-flight collisions dominate over turbulence as a suspension mechanism, yielding transport rates much higher than those for saltation. The theory presented is based on granular kinetic theory, and includes both turbulent suspension and particle-particle collisions. The wind strengths for which the calculated transport rates are relevant are beyond the published strengths of current wind tunnel experiments, so these theoretical results are an invitation to do experiments in the strong-wind regime. In order to make a connection between the regime of saltation and the regime of collisional suspension, it is necessary to better understand the interaction between the bed and the particles that collide with it. This interaction depends on the agitation of the particles of the bed. In mild winds, collisions with the bed are relatively infrequent and the local disturbance associated with a collision can relax before the next nearby collision. However, as the wind speed increases, collision become more frequent

  1. Interannual Variability of Martian Global Dust Storms: Simulations with a Low-Order Model of the General Circulation

    NASA Technical Reports Server (NTRS)

    Pankine, A. A.; Ingersoll, Andrew P.

    2002-01-01

    We present simulations of the interannual variability of martian global dust storms (GDSs) with a simplified low-order model (LOM) of the general circulation. The simplified model allows one to conduct computationally fast long-term simulations of the martian climate system. The LOM is constructed by Galerkin projection of a 2D (zonally averaged) general circulation model (GCM) onto a truncated set of basis functions. The resulting LOM consists of 12 coupled nonlinear ordinary differential equations describing atmospheric dynamics and dust transport within the Hadley cell. The forcing of the model is described by simplified physics based on Newtonian cooling and Rayleigh friction. The atmosphere and surface are coupled: atmospheric heating depends on the dustiness of the atmosphere, and the surface dust source depends on the strength of the atmospheric winds. Parameters of the model are tuned to fit the output of the NASA AMES GCM and the fit is generally very good. Interannual variability of GDSs is possible in the IBM, but only when stochastic forcing is added to the model. The stochastic forcing could be provided by transient weather systems or some surface process such as redistribution of the sand particles in storm generating zones on the surface. The results are sensitive to the value of the saltation threshold, which hints at a possible feedback between saltation threshold and dust storm activity. According to this hypothesis, erodable material builds up its a result of a local process, whose effect is to lower the saltation threshold until a GDS occurs. The saltation threshold adjusts its value so that dust storms are barely able to occur.

  2. Periodic Trajectories in Aeolian Sand Transport

    NASA Astrophysics Data System (ADS)

    Valance, A.; Jenkins, J. T.

    2014-12-01

    Saltation is the primary mode of aeolian sand transport and refers to the hoping motion of grains over the bed [1]. We develop a simple model for steady, uniform transport in aeolian saltation over a horizontal bed that is based on the computation of periodic particle trajectories in a turbulent shearing flow [2]. The wind and the particles interact through drag, and the particles collide with the bed. We consider collisions with a rigid, bumpy bed, from which the particles rebound, and an erodible particle bed, for which a collision involves both rebound and particle ejection. The difference in the nature of the collisions results in qualitative differences in the nature of the solutions for the periodic trajectories and, in particular, to differences in the dependence of the particle flow rate on the strength of the turbulent shearing. We also discuss the pertinence of this model to describe bedload transport in water. References:[1] R. A. Bagnold, « The physics of blown sand and desert dunes » , Methuen, New York (1941).[2] J.T Jenkins and A. Valance. Periodic trajectories in Aeolian saltation transport. Physics of Fluids, 2014, 26, pp. 073301

  3. Methods for Assessing the Impact of Fog Oil Smoke on Availability, Palatability, & Food Quality of Relevant Life Stages of Insects for Threatened and Endangered Species

    DTIC Science & Technology

    2007-04-09

    wood roach (Parcoblatta uhleriana [ Saussure ]), mosquito (Culex sp.), ant (Camponotus pennsylvanicus [DeGeer]), and beetle (Tenebrio molitor Linnaeus...wood roach (Parcoblatta uhleriana [ Saussure ]), beetle (Tenebrio molitor linnaeus), mosquito (Culex sp), and ant (Camponotus pennsylvanicus [De Geer

  4. Wind erosion in semiarid landscapes: Predictive models and remote sensing methods for the influence of vegetation

    NASA Technical Reports Server (NTRS)

    Musick, H. Brad; Truman, C. Randall; Trujillo, Steven M.

    1992-01-01

    Wind erosion in semi-arid regions is a significant problem for which the sheltering effect of rangeland vegetation is poorly understood. Individual plants may be considered as porous roughness elements which absorb or redistribute the wind's momentum. The saltation threshold is the minimum wind velocity at which soil movement begins. The dependence of the saltation threshold on geometrical parameters of a uniform roughness array was studied in a wind tunnel. Both solid and porous elements were used to determine relationships between canopy structure and the threshold velocity for soil transport. The development of a predictive relation for the influence of vegetation canopy structure on wind erosion of soil is discussed.

  5. Pelopscreadium aegyptense n. gen., n. sp. and Pelopscreadium spongiosum (Bray & Cribb, 1998) n. comb., (Digenea: Lepocreadiidae), each from disjunct populations of the Yellow boxfish, Ostracion cubicus Linnaeus (Ostraciidae).

    PubMed

    Dronen, Norman O; Blend, Charles K; Khalifa, Refaat M A; Mohamadain, Hoda S; Karar, Yasser F M

    2016-06-24

    Bianium spongiosum Bray & Cribb, 1998 (Lepocreadiidae), described from the yellow boxfish, Ostracion cubicus Linnaeus (Ostraciidae), off Lizard Island, Queensland, Australia, possesses a combination of the following three morphological features which distinguishes it from all the other species currently assigned to the genus: (1) large internal patches of large cells forming sponge-like pads we have termed "pelops"("pelop" sing.) laterally in the forebody extending from near the anterior extremity to about the level of the intestinal bifurcation rather than possessing a scoop; (2) ceca that reach to near the posterior extremity where they end blindly without ani; and (3) a vitellarium which is present laterally but not dorsal to the ceca. Based on this we propose the erection of Pelopscreadium n. gen. (Lepocreadiidae) with the assignment of B. spongiosum to this new genus as the type-species, Pelopscreadium spongiosum (Bray & Cribb, 1998) n. comb. Pelopscreadium aegyptense n. sp., also from the yellow boxfish but from the Red Sea off Sharm El-Naga, Egypt, is described as the second member of the new genus because it shares these three characteristics with P. spongiosum.

  6. Environmental influences on the Indo–Pacific octocoral Isis hippuris Linnaeus 1758 (Alcyonacea: Isididae): genetic fixation or phenotypic plasticity?

    PubMed Central

    Pochon, Xavier; Watling, Les

    2015-01-01

    As conspicuous modular components of benthic marine habitats, gorgonian (sea fan) octocorals have perplexed taxonomists for centuries through their shear diversity, particularly throughout the Indo–Pacific. Phenotypic incongruence within and between seemingly unitary lineages across contrasting environments can provide the raw material to investigate processes of disruptive selection. Two distinct phenotypes of the Isidid Isis hippuris Linnaeus, 1758 partition between differing reef environments: long-branched bushy colonies on degraded reefs, and short-branched multi/planar colonies on healthy reefs within the Wakatobi Marine National Park (WMNP), Indonesia. Multivariate analyses reveal phenotypic traits between morphotypes were likely integrated primarily at the colony level with increased polyp density and consistently smaller sclerite dimensions at the degraded site. Sediment load and turbidity, hence light availability, primarily influenced phenotypic differences between the two sites. This distinct morphological dissimilarity between the two sites is a reliable indicator of reef health; selection primarily acting on colony morphology, porosity through branching structure, as well as sclerite diversity and size. ITS2 sequence and predicted RNA secondary structure further revealed intraspecific variation between I. hippuris morphotypes relative to such environments (ΦST = 0.7683, P < 0.001). This evidence suggests—but does not confirm—that I. hippuris morphotypes within the WMNP are two separate species; however, to what extent and taxonomic assignment requires further investigation across its full geographic distribution. Incongruence between colonies present in the WMNP with tenuously described Isis alternatives (Isis reticulata Nutting, 1910, Isis minorbrachyblasta Zou, Huang & Wang, 1991), questions the validity of such assignments. Furthermore, phylogenetic analyses confirm early taxonomic suggestion that the characteristic jointed axis of the

  7. Environmental influences on the Indo-Pacific octocoral Isis hippuris Linnaeus 1758 (Alcyonacea: Isididae): genetic fixation or phenotypic plasticity?

    PubMed

    Rowley, Sonia J; Pochon, Xavier; Watling, Les

    2015-01-01

    As conspicuous modular components of benthic marine habitats, gorgonian (sea fan) octocorals have perplexed taxonomists for centuries through their shear diversity, particularly throughout the Indo-Pacific. Phenotypic incongruence within and between seemingly unitary lineages across contrasting environments can provide the raw material to investigate processes of disruptive selection. Two distinct phenotypes of the Isidid Isis hippurisLinnaeus, 1758 partition between differing reef environments: long-branched bushy colonies on degraded reefs, and short-branched multi/planar colonies on healthy reefs within the Wakatobi Marine National Park (WMNP), Indonesia. Multivariate analyses reveal phenotypic traits between morphotypes were likely integrated primarily at the colony level with increased polyp density and consistently smaller sclerite dimensions at the degraded site. Sediment load and turbidity, hence light availability, primarily influenced phenotypic differences between the two sites. This distinct morphological dissimilarity between the two sites is a reliable indicator of reef health; selection primarily acting on colony morphology, porosity through branching structure, as well as sclerite diversity and size. ITS2 sequence and predicted RNA secondary structure further revealed intraspecific variation between I. hippuris morphotypes relative to such environments (ΦST = 0.7683, P < 0.001). This evidence suggests-but does not confirm-that I. hippuris morphotypes within the WMNP are two separate species; however, to what extent and taxonomic assignment requires further investigation across its full geographic distribution. Incongruence between colonies present in the WMNP with tenuously described Isis alternatives (Isis reticulataNutting, 1910, Isis minorbrachyblastaZou, Huang & Wang, 1991), questions the validity of such assignments. Furthermore, phylogenetic analyses confirm early taxonomic suggestion that the characteristic jointed axis of the Isididae is in

  8. Anthelmintic efficacy of pumpkin seed (Cucurbita pepo Linnaeus, 1753) on ostrich gastrointestinal nematodes in a semiarid region of Paraíba State, Brazil.

    PubMed

    Feitosa, Thais Ferreira; Vilela, Vinícius Longo Ribeiro; Athayde, Ana Célia Rodrigues; Braga, Fábio Ribeiro; Dantas, Elaine Silva; Vieira, Vanessa Diniz; de Melo, Lídio Ricardo Bezerra

    2013-01-01

    The aim of this study was to verify the in vivo effectiveness of pumpkin seed (Curcubita pepo Linnaeus, 1753) in naturally infected ostriches in the Cariri zone, semiarid region of Paraíba State, Brazil. Forty-eight ostriches were used, African Black breed, of 14 to 36 months old, naturally infected by gastrointestinal nematodes. These animals were divided into four groups of 12 ostriches. Group 1 consists of animals treated with 0.5 g/kg live weight (l. w.) of pumpkin seed meal; group 2 received 1 g/kg l. w. of pumpkin seed meal; group 3 was treated with Albendazole 5 %, at the dosage of 1 mL/10 kg l. w.; and Group 4 was the control group and do not received treatment. Groups 1 and 2 received the treatment for three consecutive days, orally, at intervals of 7 days, totaling nine administrations. The Albendazole 5 % was administered one time, at the beginning of the experiment, according to the manufacturer's recommendations. The groups treated with pumpkin seed showed a significant decrease in egg counts per gram of feces (EPG), wherein group 2 (1 g/kg l. w.) was the most effective. The control and drug groups showed no reduction in EPG. The results of the present study demonstrate that the administration of pumpkin seed was effective in controlling gastrointestinal helminths in naturally infected ostriches.

  9. Computer Modeling of Sand Transport on Mars Using a Compart-Mentalized Fluids Algorithm (CFA)

    NASA Technical Reports Server (NTRS)

    Marshall, J.; Stratton, D.

    1999-01-01

    It has been postulated that aeolian transport on Mars may be significantly different from that on Earth. From laboratory experiments simulating martian grain transport [2], it has been observed that (saltating) grains striking the bed can cause hundreds of secondary reptation trajectories when impact occurs at speeds postulated for Mars. Some of the ballistically induced trajectories "die ouf' and effectively join the ranks on the creep population that is merely nudged along by impact. Many of the induced reptation trajectories, however, are sufficiently high for the grains to become part of the saltation load (it is irrelevant to the boundary layer how a grain attained its initial lift force). When these grains, in turn, strike the surface, they too are capable of inducing more reptating grains. This cascading effect has been discussed in connection with terrestrial aeolian transport in an attempt to dispel the notion that sand motion is divisible only into creep and saltation loads. On Earth, only a few grains are splashed by impact. On Mars, it may be hundreds. We developed a computer model to address this phenomenon because there are some important ramifications: First, this ratio may mean that martian aeolian transport is dominated by reptation flux rather than saltation. On Earth, the flux would be a roughly balanced mixture between reptation/creep and saltation. On Venus, there would be no transport other than by saltation. In other words, an understanding of planetary aeolian processes may not be necessarily understood by extrapolating from the "Earth case", with only gravity and atmospheric density/viscosity being considered as variables. Second, the reptation flux on Mars may be self sustaining, so that little input is required by the wind once transport has been initiated. The number of grains saturating the boundary layer near the bed may mean that average grain speed on Mars might conceivably be less than that on Earth. This would say much for models

  10. The decapod fauna (Axiidea, Anomura, Brachyura) from the Late Pleistocene of Trumbacà, Reggio Calabria (Calabria, southern Italy).

    PubMed

    Garassino, Alessandro; Pasini, Giovanni; De Angeli, Antonio; Hyžný, Matúš

    We report a rich faunal assemblage from the Tyrrhenian (Late Pleistocene) of Trumbacà, located in the southern area of Reggio Calabria (Calabria, southern Italy). The only brachyuran reported to date from this locality is Ranilia constricta (A. Milne Edwards, 1880) by Vazzana (2008). The studied specimens have been assigned, as follows: ? Corallianassa sp., Dardanus arrosor (Herbst, 1796), Dardanus substriatus (A. Milne Edwards, 1861), Paguristes cf. P. syrtensis de Saint Laurent 1970, Anapagurus sp., Ranilia constricta (A. Milne Edwards, 1880), Ranina propinqua Ristori, 1891, Ebalia cf. E. deshayesi Lucas, 1846, Ilia nucleus (Linnaeus, 1758), Medorippe lanata (Linnaeus, 1767), Calappa granulata (Linnaeus, 1758), Pisa armata (Latreille, 1803), Derilambrus cf. D. angulifrons (Latreille, 1825), Atelecyclus undecimdentatus (Herbst, 1783), Carcinus sp., Pilumnus hirtellus (Linnaeus, 1761), and Xantho cf. X. incisus (Leach, 1814). The studied assemblage enlarges our knowledge on the evolution of the Mediterranean decapod faunas.

  11. Vessel noise pollution as a human threat to fish: assessment of the stress response in gilthead sea bream (Sparus aurata, Linnaeus 1758).

    PubMed

    Celi, Monica; Filiciotto, Francesco; Maricchiolo, Giulia; Genovese, Lucrezia; Quinci, Enza Maria; Maccarrone, Vincenzo; Mazzola, Salvatore; Vazzana, Mirella; Buscaino, Giuseppa

    2016-04-01

    This study examined the effects of boat noise pollution on the stress indices of gilthead sea bream (Sparus aurata, Linnaeus 1758). To assess the stress response in these fish, biometric values and plasma parameters such as ACTH, cortisol, glucose, lactate, haematocrit, Hsp70, total protein, cholesterol, triglycerides and osmolarity were analysed. After acclimatization of the animals, the experiment was carried out in a tank fitted with underwater speakers where the fish were exposed to sound treatments (in duplicate) consisting of: 10 days of no sound (control treatment; the animals were only exposed to the experimental tank's background noise) and 10 days of noise derived from original recordings of motor boats, including recreational boats, hydrofoil, fishing boat and ferry boat (vessel noise treatment). The exposure to noise produced significant variations in almost all the plasma parameters assessed, but no differences were observed in weights and fork lengths. A PERMANOVA analysis highlighted significantly increased values (p < 0.05) of ACTH, cortisol, glucose, lactate, haematocrit, Hsp70, cholesterol, triglycerides and osmolarity in the fish exposed to vessel noise for 10 days. This study clearly highlights that anthropogenic noise negatively affects fish, and they are valuable targets for detailed investigations into the effects of this global pollutant. Finally, these experimental studies could represent part of the science that is able to improve the quality of the policies related to management plans for maritime spaces (Marine Strategy Framework Directive 56/2008 CE) that are aimed at stemming this pollutant phenomenon.

  12. Unique Extracellular Matrix Heparan Sulfate from the Bivalve Nodipecten nodosus (Linnaeus, 1758) Safely Inhibits Arterial Thrombosis after Photochemically Induced Endothelial Lesion*

    PubMed Central

    Gomes, Angélica M.; Kozlowski, Eliene O.; Pomin, Vitor H.; de Barros, Cintia Monteiro; Zaganeli, José L.; Pavão, Mauro S. G.

    2010-01-01

    Heparin-like glycans with diverse disaccharide composition and high anticoagulant activity have been described in several families of marine mollusks. The present work focused on the structural characterization of a new heparan sulfate (HS)-like polymer isolated from the mollusk Nodipecten nodosus (Linnaeus, 1758) and on its anticoagulant and antithrombotic properties. Total glycans were extracted from the mollusk and fractionated by ethanol precipitation. The main component (>90%) was identified as HS-like glycosaminoglycan, representing ∼4.6 mg g−1 of dry tissue. The mollusk HS resists degradation with heparinase I but is cleaved by nitrous acid. Analysis of the mollusk glycan by one-dimensional 1H, two-dimensional correlated spectroscopy, and heteronuclear single quantum coherence nuclear magnetic resonance revealed characteristic signals of glucuronic acid and glucosamine residues. Signals corresponding to anomeric protons of nonsulfated, 3- or 2-sulfated glucuronic acid as well as N-sulfated and/or 6-sulfated glucosamine were also observed. The mollusk HS has an anticoagulant activity of 36 IU mg−1, 5-fold lower than porcine heparin (180 IU mg−1), as measured by the activated partial thromboplastin time assay. It also inhibits factor Xa (IC50 = 0.835 μg ml−1) and thrombin (IC50 = 9.3 μg ml−1) in the presence of antithrombin. In vivo assays demonstrated that at the dose of 1 mg kg−1, the mollusk HS inhibited thrombus growth in photochemically injured arteries. No bleeding effect, factor XIIa-mediated kallikrein activity, or toxic effect on fibroblast cells was induced by the invertebrate HS at the antithrombotic dose. PMID:20053999

  13. Effects of 200 Gy 60Co-γ Radiation on the Regulation of Antioxidant Enzymes, Hsp70 Genes, and Serum Molecules of Plutella xylostella (Linnaeus).

    PubMed

    Li, Xiaoxue; Luo, Lingyan; Karthi, Sengodan; Zhang, Ke; Luo, Jianjun; Hu, Qiongbo; Weng, Qunfang

    2018-04-26

    The diamondback moth, Plutella xylostella (Linnaeus), is one of the notorious pests causing substantial loses to many cruciferous vegetables across the nations. The effects of 60 Co-γ radiation on physiology of P. xylostella were investigated and the results displayed that 200 Gy irradiation significantly alters the antioxidant enzyme regulation in six-day-old male pupae of P. xylostella . First, in our research, we detected Oxidase system and stress response mechanism of irradiated pupae, the results displayed that 200 Gy irradiation significantly alters the antioxidant enzyme regulation in six-day-old male pupae of P. xylostella . The levels of superoxide dismutase (SOD) and catalase (CAT) were increased significantly in contrast the level of peroxidase (POD) and glutathione S-transferase (GST) were decreased in 12⁻24 h post-treatment. The heat shock proteins (Hsps) gene expression level was significant increasing, maximum > 2-folds upregulation of genes were observed in peak. However, they also had a trend of gradual recovery with development. Second, we detected the testis lactate dehydrogenase (LDH) and acid phosphatase (ACP) activity found that in male adults testis they increased significantly than control during its development. Thus the present research investigation highlights that the 60 Co-γ radiation treatments alters the physiological development of diamondback moth. The results showed that 200 Gy dosage resulted in stress damage to the body and reproductive system of the diamondback moth.

  14. The decapod fauna (Axiidea, Anomura, Brachyura) from the Late Pleistocene of Trumbacà, Reggio Calabria (Calabria, southern Italy)

    PubMed Central

    Garassino, Alessandro; Pasini, Giovanni; De Angeli, Antonio; Hyžný, Matúš

    2015-01-01

    We report a rich faunal assemblage from the Tyrrhenian (Late Pleistocene) of Trumbacà, located in the southern area of Reggio Calabria (Calabria, southern Italy). The only brachyuran reported to date from this locality is Ranilia constricta (A. Milne Edwards, 1880) by Vazzana (2008). The studied specimens have been assigned, as follows: ?Corallianassa sp., Dardanus arrosor (Herbst, 1796), Dardanus substriatus (A. Milne Edwards, 1861), Paguristes cf. P. syrtensis de Saint Laurent 1970, Anapagurus sp., Ranilia constricta (A. Milne Edwards, 1880), Ranina propinqua Ristori, 1891, Ebalia cf. E. deshayesi Lucas, 1846, Ilia nucleus (Linnaeus, 1758), Medorippe lanata (Linnaeus, 1767), Calappa granulata (Linnaeus, 1758), Pisa armata (Latreille, 1803), Derilambrus cf. D. angulifrons (Latreille, 1825), Atelecyclus undecimdentatus (Herbst, 1783), Carcinus sp., Pilumnus hirtellus (Linnaeus, 1761), and Xantho cf. X. incisus (Leach, 1814). The studied assemblage enlarges our knowledge on the evolution of the Mediterranean decapod faunas. PMID:26689358

  15. Inhibition of lung cancer cells A549 and H460 by curcuminoid extracts and nanoemulsions prepared from Curcuma longa Linnaeus.

    PubMed

    Chang, Hong-Bin; Chen, Bing-Huei

    2015-01-01

    The objectives of this study were to explore the inhibition mechanism of lung cancer cells A549 and H460 by curcuminoid extracts and nanoemulsions prepared from Curcuma longa Linnaeus. In addition, human bronchus epithelial cell line BEAS-2B (normal cell) was selected for comparison. A high-performance liquid chromatography (HPLC) method was developed to separate and quantify the various curcuminoids in C. longa extract, including curcumin (1,714.5 μg/mL), demethoxycurcumin (1,147.4 μg/mL), and bisdemethoxycurcumin (190.2 μg/mL). A high-stability nanoemulsion composed of Tween 80, water, and curcuminoid extract was prepared, with mean particle size being 12.6 nm. The cell cycle was retarded at G2/M for both the curcuminoid extract and nanoemulsion treatments; however, the inhibition pathway may be different. H460 cells were more susceptible to apoptosis than A549 cells for both curcuminoid extract and nanoemulsion treatments. Growth of BEAS-2B remained unaffected for both the curcuminoid extract and nanoemulsion treatments, with a concentration range from 1 to 4 μg/mL. Also, the activities of caspase-3, caspase-8, and caspase-9 followed a dose-dependent increase for both A549 and H460 cells for both the treatments, accompanied by a dose-dependent increase in cytochrome C expression and a dose-dependent decrease in CDK1 expression. Interestingly, a dose-dependent increase in cyclin B expression was shown for A549 cells for both the treatments, while a reversed trend was found for H460 cells. Both mitochondria and death receptor pathways may be responsible for apoptosis of both A549 and H460 cells.

  16. Pre-soaking of the feed pellets: a trick for successful feed utilization in juvenile green turtles (Chelonia mydas Linnaeus, 1758).

    PubMed

    Kanghae, H; Thongprajukaew, K; Phromkunthong, W; Plangsri, S; Jatupornpitukchat, S; Kittiwattanawong, K

    2017-04-01

    Pre-soaking of the feed pellets in water can improve feed utilization in juvenile green turtles (Chelonia mydas Linnaeus, 1758), but the pre-soaking has not previously been optimized. This study aimed to optimize the water amount used for pre-soaking the pellets. The experiments followed a completely randomized design with three replications of each dietary treatment group. Initially 10-day-old green turtles (20-22 g body weight) were treated in an indoor aquaculture system for 3 months. The dietary treatment pellets were pre-soaked with 0.3, 0.5 or 0.7 (v/w) relative amounts of water that are here termed soaking ratios. At the end of experiment, there were no significant differences in survival (96% on average) and growth (average body weight 75.34 g and specific growth rate 2%/day, on average) of turtles in three dietary treatments (p > 0.05). Feed utilization was the best in turtles fed with 0.7 pre-soaked ratio, as indicated by significant reductions (p < 0.05) in the feeding rate (7.44% body weight/day) and the feed conversion ratio (1.12 g feed/g gain). Digestion was also improved by the induction of faecal digestive enzymes as well as the faecal thermal properties. The rapid growth did not negatively affect the general haematological parameters of reared turtles. These findings indicate that the pre-soaking of feed pellets at the optimal soaking ratio (1:0.7 w/v of pellet to water) can contribute through improved feed utilization of green turtles. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  17. The formulation of the essential oil of Piper aduncum Linnaeus (Piperales: Piperaceae) increases its efficacy as an insect repellent.

    PubMed

    Mamood, S N H; Hidayatulfathi, O; Budin, S B; Ahmad Rohi, G; Zulfakar, M H

    2017-02-01

    The essential oil (EO) of Piper aduncum Linnaeus, known as 'sireh lada' to locals Malaysian, has the potential to be used as an alternative to synthetic insect repellents such as N,N-diethyl-meta-toluamide. However, the EO's efficacy as a repellent decreases after application due to the high volatility of its active ingredients. A number of studies have showed that optimizing the formulation of plant-based EOs can improve their efficacy as repellents. The present study sought to evaluate the effectiveness of 10% P. aduncum EO in ethanol and in three different semisolid formulations: ointment, cream and gel. These formulations were tested on Aedes aegypti under laboratory conditions. Each formulation was applied to the subject's hands, which were then inserted into a cage containing 25 nulliparous A. aegypti. The number of mosquitoes landing on or biting each subject's hand was recorded, and the repellency percentage, landing/biting percentage and protection time for each of the formulations were compared. There were no statistically significant differences between the semisolid EO formulations with regards to the repellency percentage and the landing/biting percentage at 4 h post-application. All three semisolid EO formulations were able to repel >65% of the A. aegypti at 4 h post-application. The EO ointment formulation provided a protection time (182.5 ± 16.01 min) that was statistically significantly longer than that associated with the EO gel formulation (97.5 ± 14.93 min). Meanwhile, the EO cream formulation provided a protection time of 162.5 ± 6.29 min. As the EO cream and ointment formulations displayed better repellent properties than the EO gel formulation, they appear to be the most promising P. aduncum EO formulations to be developed and commercialized as alternatives to synthetic repellents.

  18. Specialized odorant receptors in social insects that detect cuticular hydrocarbon cues and candidate pheromones.

    PubMed

    Pask, Gregory M; Slone, Jesse D; Millar, Jocelyn G; Das, Prithwiraj; Moreira, Jardel A; Zhou, Xiaofan; Bello, Jan; Berger, Shelley L; Bonasio, Roberto; Desplan, Claude; Reinberg, Danny; Liebig, Jürgen; Zwiebel, Laurence J; Ray, Anandasankar

    2017-08-17

    Eusocial insects use cuticular hydrocarbons as components of pheromones that mediate social behaviours, such as caste and nestmate recognition, and regulation of reproduction. In ants such as Harpegnathos saltator, the queen produces a pheromone which suppresses the development of workers' ovaries and if she is removed, workers can transition to a reproductive state known as gamergate. Here we functionally characterize a subfamily of odorant receptors (Ors) with a nine-exon gene structure that have undergone a massive expansion in ants and other eusocial insects. We deorphanize 22 representative members and find they can detect cuticular hydrocarbons from different ant castes, with one (HsOr263) that responds strongly to gamergate extract and a candidate queen pheromone component. After systematic testing with a diverse panel of hydrocarbons, we find that most Harpegnathos saltator Ors are narrowly tuned, suggesting that several receptors must contribute to detection and discrimination of different cuticular hydrocarbons important in mediating eusocial behaviour.Cuticular hydrocarbons (CHC) mediate the interactions between individuals in eusocial insects, but the sensory receptors for CHCs are unclear. Here the authors show that in ants such as H. saltator, the 9-exon subfamily of odorant receptors (HsOrs) responds to CHCs, and ectopic expression of HsOrs in Drosophila neurons imparts responsiveness to CHCs.

  19. Meadow katydids (Orthoptera: Tettigoniidae: Conocephalini) from the Central-West Region of Brazil: Morphological, bioacoustic and cytogenetic study.

    PubMed

    Chamorro-Rengifo, Juliana; Silva, Bruno cansanÇÃo; Olivier, Renan da Silva; Braun, Holger; Araujo, Douglas

    2018-03-04

    Three species of Conocephalus and two of Euxiphidion from several localities of the Central-West Region of Brazil were studied. Conocephalus goianus Piza, 1977, C. saltator (Saussure, 1859) and C. versicolor (Redtenbacher, 1891) are recorded for the first time from Mato Grosso do Sul, one new species Euxiphidion veroni sp. nov. is described, and a new combination, Euxiphidion caizanum comb. nov. is proposed. The calling songs of C. saltator, C. versicolor, and E. veroni sp. nov. are described. All these three species call very continuously, also in the daytime. The three species of Conocepha-lus have mitotic metaphases with 2n♂ = 33 = 32 + X and 2n♀ = 34 = 32 + XX. Euxiphidion caizanum comb. nov. and    E. veroni sp. nov. have 2n♂ = 31 = 30 + X and 2n♀ = 32 = 30 + XX. Most of the autosomes of C. saltator and C. versicolor are meta/submetacentric, differing from C. goianus that has seven biarmed and nine monoarmed autosomes. Both Euxiphidion species present mostly telo/subtelocentric autosomes. The X chromosome is metacentric, and the largest element of the karyotype in the five species. No interstitial telomeric site (ITS) was observed in mitotic metaphases submitted to telomeric fluorescent in situ hybridization. Ecological aspects of the studied species are discussed.

  20. The importance of pollen chemistry in evolutionary host shifts of bees

    PubMed Central

    Vanderplanck, Maryse; Vereecken, Nicolas J.; Grumiau, Laurent; Esposito, Fabiana; Lognay, Georges; Wattiez, Ruddy; Michez, Denis

    2017-01-01

    Although bee-plant associations are generally maintained through speciation processes, host shifts have occurred during evolution. Understanding shifts between both phylogenetically and morphologically unrelated plants (i.e., host-saltation) is especially important since they could have been key processes in the origin and radiation of bees. Probably far from being a random process, such host-saltation might be driven by hidden constraints associated with plant traits. We selected two clades of oligolectic bees (i.e., Colletes succinctus group and Melitta leporina group) foraging on co-flowering but unrelated host-plants to test this hypothesis. We analyzed floral scent, floral color and chemical composition of pollen from host and non-host plants of these two clades. We did not find evidence for host-plant evolution in the Melitta leporina group driven by one of the assayed floral traits. On the contrary, hosts of the C. succinctus group display similar primary nutritive content of pollen (i.e., amino acids and sterols) but not similar floral scent or color, suggesting that shared pollen chemistry probably mediates saltation in this clade. Our study revealed that constraints shaping floral associations are diverse and clearly depend on species life-history traits, but evidence suggests that pollen chemistry may act as a major floral filter and guide evolutionary host-shifts. PMID:28216663

  1. Unique Aeolian Transport Mechanisms on Mars: Respective Roles of Percussive and Repercussive Grain Populations in the Sediment Load

    NASA Technical Reports Server (NTRS)

    Marshall, John R.

    1999-01-01

    Experiments show that when sand-size grains impact a sediment surface with energy levels commensurate for Mars, small craters are formed by the ejection of several hundred grains from the bed. The experiments were conducted with a modified crossbow in which a sand-impelling sabot replaced the bolt-firing mechanism. Individual grains of sand could be fired at loose sand targets to observe ballistic effects unhindered by aerodynamic mobilization of the bed. Impact trajectories simulated the saltation process on dune surfaces. Impact craters were not elongated despite glancing (15 deg.) bed impact; the craters were very close to being circular. High-speed photography showed them to grow in both diameter and depth after the impactor had ricochetted from the crater site. The delayed response of the bed was "explosive" in nature, and created a miniature ejecta curtain spreading upward and outward for many centimeters for impact of 100-300 micron-diameter grains into similar material. This behavior is explained by deposition of elastic energy in the bed by the "percussive" grain. Impact creates a subsurface stress regime or "quasi-Boussinesq" compression field. Elastic recovery of the bed occurs by dilatancy; shear stresses suddenly convert the grains to open packing and they consequently become forcefully ejected from the site. Random jostling of the grains causes radial homogenization of stress vectors and a resulting circular crater. A stress model based on repercussive bed dilatancy and interparticle adhesive forces (for smaller grains) predicts, to first order, the observed crater volumes for various impact conditions. On earth, only a few grains are mobilized by a percussive saltating grain; some grains are "knudged" along the ground, and some are partly expelled on short trajectories. These motions constitute reptation transport. On Mars, saltation and reptation become indistinct: secondary or "repercussive" trajectories have sufficient vertical impulse to create a

  2. Unique Aeolian Transport Mechanisms on Mars: Respective Roles of Percussive and Repercussive Grain Populations in the Sediment Load

    NASA Technical Reports Server (NTRS)

    Marshall, John R.

    1999-01-01

    Experiments show that when sand-size grains impact a sediment surface with energy levels commensurate for Mars, small craters are formed by the ejection of several hundred grains from the bed. The experiments were conducted with a modified crossbow in which a sand-impelling sabot replaced the bolt-firing mechanism. Individual grains of sand could be fired at loose sand targets to observe ballistic effects unhindered by aerodynamic mobilization of the bed. Impact trajectories simulated the saltation process on dune surfaces. Impact craters were not elongated despite glancing (15 deg.) bed impact; the craters were very close to being circular. High-speed photography showed them to grow in both diameter and depth after the impactor had ricochetted from the crater site. The delayed response of the bed was "explosive" in nature, and created a miniature ejecta curtain spreading upward and outward for many centimeters for impact of 100-300 um-diameter grains into similar material. This behavior is explained by deposition of elastic energy in the bed by the "percussive" grain. Impact creates a subsurface stress regime or "quasi-Boussinesq" compression field. Elastic recovery of the bed occurs by dilatancy; shear stresses suddenly convert the grains to open packing and they consequently become forcefully ejected from the site. Random jostling of the grains causes radial homogenization of stress vectors and a resulting circular crater. A stress model based on repercussive bed dilatancy and interparticle adhesive forces (for smaller grains) predicts, to first order, the observed crater volumes for various impact conditions. On earth, only a few grains are mobilized by a percussive saltating grain; some grains are "knudged" along the ground, and some are partly expelled on short trajectories. These motions constitute reptation transport. On Mars, saltation and reptation become indistinct: secondary or "repercussive" trajectories have sufficient vertical impulse to create a

  3. Populations and home range relationships of the box turtle, Terrapene carolina (Linnaeus)

    USGS Publications Warehouse

    Stickel, L.F.

    1949-01-01

    A population study of Terrapene carolina (Linnaeus) was made at the Patuxent Research Refuge, Maryland, from 1944 to 1947. A thirty acre area in bottomland forest was selected for intensive study. Turtles were marked by filing notches in marginal scutes according to a code. Turtles make extensive use of brushy shelter during the day as well.as at night. Gully banks and woods openings are used for sunning. Nights are usually spent in a 'form,' constructed by the turtle in leaves, debris, or earth. A form may be used once or it may be used repeatedly by the same or different turtles. Weather conditions most favorable to turtle activity are high humidity, warm sunny days, and frequent rains. Periods of activity are alternated with periods of quiet, even in favorable weather. There is no evidence for territorialism. Ranges of turtles of all ages and both sexes overlap grossly. Turtles are frequently found near each other but no antagonistic behavior has been observed. Adult turtles occupy specific home ranges which they maintain from year to year. Turtles retained their ranges even though a flood that completely covered the study area. Maximum home range diameters were determined by measurements of the mapped ranges of individual turtles. There was no significant difference between sizes of male and female ranges: males 33O+ 26 feet, females 37O+29 feet. A trail-laying device was used in following travel routes for 456 turtle days. Normal movements within the home range are characterized by (1) turns, doublings, detours, and criss-crossing paths, (2) interspersion of fairly direct traverses of the home range, (3) frequently repeated travels over certain routes. Maximum limits of the home range are ordinarily reached within a few days or weeks, although some turtles cover only one portion of the range at a time. Some turtles have two home ranges. One of these turtles was followed with a trailer for 161 days in 1946 and 1947. Trips outside the home range are made by

  4. Absorbed Dose Rate Due to Intake of Natural Radionuclides by Tilapia Fish (Tilapia nilotica,Linnaeus, 1758) Estimated Near Uranium Mining at Caetité, Bahia, Brazil

    NASA Astrophysics Data System (ADS)

    Pereira, Wagner de S.; Kelecom, Alphonse; Py Júnior, Delcy de Azevedo

    2008-08-01

    The uranium mining at Caetité (Uranium Concentrate Unit—URA) is in its operational phase. Aiming to estimate the radiological environmental impact of the URA, a monitoring program is underway. In order to preserve the biota of the deleterious effects from radiation and to act in a pro-active way as expected from a licensing body, the present work aims to use an environmental protection methodology based on the calculation of absorbed dose rate in biota. Thus, selected target organism was the Tilapia fish (Tilapia nilotica, Linnaeus, 1758) and the radionuclides were: uranium (U-238), thorium (Th-232), radium (Ra-226 and Ra-228) and lead (Pb-210). As, in Brazil there are no radiation exposure limits adopted for biota the value proposed by the Department of Energy (DOE) of the United States of 3.5×103 μGy y-1 has been used. The derived absorbed dose rate calculated for Tilapia was 2.51×100 μGy y-1, that is less than 0.1% of the dose limit established by DOE. The critical radionuclide was Ra-226, with 56% of the absorbed dose rate, followed by U-238 with 34% and Th-232 with 9%. This value of 0.1% of the limit allows to state that, in the operational conditions analyzed, natural radionuclides do not represent a radiological problem to biota.

  5. Assessment of heavy metal contamination in Hediste diversicolor (O.F. Müller, 1776), Mugil cephalus (Linnaeus, 1758), and surface sediments of Bafa Lake (Eastern Aegean).

    PubMed

    Aydin-Onen, S; Kucuksezgin, F; Kocak, F; Açik, S

    2015-06-01

    In the present study, the bioaccumulation of six heavy metals (Cd, Cr, Cu, Hg, Pb, and Zn) in Hediste (Nereis) diversicolor (O.F. Müller, 1776) and also in the muscle and liver of Mugil cephalus (Linnaeus, 1758) collected from seven stations in the Bafa Lake was investigated. Sediment samples were also collected in each site to assess heavy metal levels and to provide additional information on pollution of the lake. The mean concentrations of heavy metals in sediment, H. diversicolor, and muscle and liver of the fish were found to be in the magnitude of Cr>Pb>Zn>Cu>Cd>Hg, Zn>Cu>Cr>Pb>Hg>Cd, Zn>Cu>Pb>Cr >Hg>Cd, and Cu>Zn>Cr>Cd>Pb>Hg, respectively. Hg, Cu, and Zn in H. diversicolor and Hg and Zn in muscle and also Hg, Cd, Cu, and Zn in liver of fish accumulated in a higher degree than in sediment. There was no clear relationship between metal concentrations in sediments, polychaetes, and fish, except Cr. According to international criteria and Turkish regulations, Pb and Zn values in edible muscle of the fish collected from stations S6 and S5 exceeded the food safety limits, respectively. The results of this study suggest that these sentinel species can be considered as good anthropogenic biological indicators for heavy metal pollution along the Bafa Lake.

  6. Evaluation of architectural and histopathological biomarkers in the intestine of brown trout (Salmo trutta Linnaeus, 1758) challenged with environmental pollution.

    PubMed

    Barišić, Josip; Filipović Marijić, Vlatka; Mijošek, Tatjana; Čož-Rakovac, Rozelindra; Dragun, Zrinka; Krasnići, Nesrete; Ivanković, Dušica; Kružlicová, Dáša; Erk, Marijana

    2018-06-14

    In the present study novel histopathological approach, using fish intestine as a sensitive bioindicator organ of pollution impact in the freshwater ecosystem, was proposed. Histopathological alterations were compared between native brown trout (Salmo trutta Linnaeus, 1758) from the reference (Krka River spring) and pollution impacted location (influence of technological/municipal wastewaters and agricultural runoff near the Town of Knin) of the karst Krka River in Croatia. In brown trout from both locations, severe parasitic infestation with acanthocephalan species Dentitruncus trutae was found, enabling evaluation of acanthocephalan infestation histopathology, which indicated parasite tissue reaction in a form of inflammatory, necrotic and hyperplastic response that extended throughout lamina epithelialis mucosae, lamina propria, and lamina muscularis mucosae. New semi-quantitative histological approach was proposed in order to foresee alterations classified in three reaction patterns: control tissue appearance, moderate (progressive) tissue impairment and severe (regressive and inflammatory) tissue damage. The most frequent progressive alteration was hyperplasia of epithelium on the reference site, whereas the most frequent regressive alterations were atrophy and necrosis seen on the polluted site. Furthermore, histopathological approach was combined with micromorphological and macromorphological assessment as an additional indicator of pollution impact. Among 15 observed intestinal measures, two biomarkers of intestinal tissue damage were indicated as significant, height of supranuclear space (hSN) and number of mucous cells over 100 μm fold distance of intestinal mucosa (nM), which measures were significantly lower in fish from polluted area compared to the reference site. Obtained results indicated that combined histological and morphological approach on fish intestinal tissue might be used as a valuable biological tool for assessing pollution impact on

  7. Inhibition of lung cancer cells A549 and H460 by curcuminoid extracts and nanoemulsions prepared from Curcuma longa Linnaeus

    PubMed Central

    Chang, Hong-Bin; Chen, Bing-Huei

    2015-01-01

    The objectives of this study were to explore the inhibition mechanism of lung cancer cells A549 and H460 by curcuminoid extracts and nanoemulsions prepared from Curcuma longa Linnaeus. In addition, human bronchus epithelial cell line BEAS-2B (normal cell) was selected for comparison. A high-performance liquid chromatography (HPLC) method was developed to separate and quantify the various curcuminoids in C. longa extract, including curcumin (1,714.5 μg/mL), demethoxycurcumin (1,147.4 μg/mL), and bisdemethoxycurcumin (190.2 μg/mL). A high-stability nanoemulsion composed of Tween 80, water, and curcuminoid extract was prepared, with mean particle size being 12.6 nm. The cell cycle was retarded at G2/M for both the curcuminoid extract and nanoemulsion treatments; however, the inhibition pathway may be different. H460 cells were more susceptible to apoptosis than A549 cells for both curcuminoid extract and nanoemulsion treatments. Growth of BEAS-2B remained unaffected for both the curcuminoid extract and nanoemulsion treatments, with a concentration range from 1 to 4 μg/mL. Also, the activities of caspase-3, caspase-8, and caspase-9 followed a dose-dependent increase for both A549 and H460 cells for both the treatments, accompanied by a dose-dependent increase in cytochrome C expression and a dose-dependent decrease in CDK1 expression. Interestingly, a dose-dependent increase in cyclin B expression was shown for A549 cells for both the treatments, while a reversed trend was found for H460 cells. Both mitochondria and death receptor pathways may be responsible for apoptosis of both A549 and H460 cells. PMID:26345201

  8. Simplification of a dust emission scheme and comparison with data

    NASA Astrophysics Data System (ADS)

    Shao, Yaping

    2004-05-01

    A simplification of a dust emission scheme is proposed, which takes into account of saltation bombardment and aggregates disintegration. The statement of the scheme is that dust emission is proportional to streamwise saltation flux, but the proportionality depends on soil texture and soil plastic pressure p. For small p values (loose soils), dust emission rate is proportional to u*4 (u* is friction velocity) but not necessarily so in general. The dust emission predictions using the scheme are compared with several data sets published in the literature. The comparison enables the estimate of a model parameter and soil plastic pressure for various soils. While more data are needed for further verification, a general guideline for choosing model parameters is recommended.

  9. Absorbed Dose Rate Due to Intake of Natural Radionuclides by Tilapia Fish (Tilapia nilotica,Linnaeus, 1758) Estimated Near Uranium Mining at Caetite, Bahia, Brazil

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

    Pereira, Wagner de S; Universidade Federal Fluminense, Programa de Pos-graduacao em Biologia Marinha; Kelecom, Alphonse

    2008-08-07

    The uranium mining at Caetite (Uranium Concentrate Unit--URA) is in its operational phase. Aiming to estimate the radiological environmental impact of the URA, a monitoring program is underway. In order to preserve the biota of the deleterious effects from radiation and to act in a pro-active way as expected from a licensing body, the present work aims to use an environmental protection methodology based on the calculation of absorbed dose rate in biota. Thus, selected target organism was the Tilapia fish (Tilapia nilotica, Linnaeus, 1758) and the radionuclides were: uranium (U-238), thorium (Th-232), radium (Ra-226 and Ra-228) and lead (Pb-210).more » As, in Brazil there are no radiation exposure limits adopted for biota the value proposed by the Department of Energy (DOE) of the United States of 3.5x10{sup 3} {mu}Gy y{sup -1} has been used. The derived absorbed dose rate calculated for Tilapia was 2.51x10{sup 0} {mu}Gy y{sup -1}, that is less than 0.1% of the dose limit established by DOE. The critical radionuclide was Ra-226, with 56% of the absorbed dose rate, followed by U-238 with 34% and Th-232 with 9%. This value of 0.1% of the limit allows to state that, in the operational conditions analyzed, natural radionuclides do not represent a radiological problem to biota.« less

  10. [Spatial change of the grain-size of aeolian sediments in Qira oasis-desert ecotone, Northwest China].

    PubMed

    Lin, Yong Chong; Xu, Li Shuai

    2017-04-18

    In order to understand the environmental influence of oasis-desert ecotone to oasis ecological system, we comparatively analyzed the grain size characteristics of various aeolian sediments, including the sediments in oasis-desert ecotone, shelterbelt and the inside oasis and in Qira River valley. The results showed that the grain size characteristics (including grain-size distribution curve, grain size parameters, and content of different size classes) of sediments in the oasis-desert ecotone were consistent along the prevailing wind direction with a grain-size range of 0.3-200 μm and modal size of 67 μm. All of the sediments were good sorting and mainly composed of suspension components and saltation components, but not denatured saltation and creeping components (>200 μm). They were typically aeolian deposits being short-range transported. The grain sizes of sediments in oasis-desert ecotone were smaller than that in the material sources of Qira River valley and desert (0.3-800 μm), but very similar to those of the modern aeolian deposits in oasis-desert ecotone, shelterbelt and the inside oasis. The denatured saltation and creep components (>200 μm) were suppressed to transport into oasis-desert ecotone because of the high vegetation cover in oasis-desert ecotone. Therefore, like the shelterbelts, the oasis-desert ecotone could also block the invasion of desert. They safeguarded the oasis ecological environment together.

  11. Aeolian bedforms, yardangs, and indurated surfaces in the Tharsis Montes as seen by the HiRISE Camera: Evidence for dust aggregates

    USGS Publications Warehouse

    Bridges, N.T.; Banks, M.E.; Beyer, R.A.; Chuang, F.C.; Noe Dobrea, E.Z.; Herkenhoff, K. E.; Keszthelyi, L.P.; Fishbaugh, K.E.; McEwen, A.S.; Michaels, T.I.; Thomson, B.J.; Wray, J.J.

    2010-01-01

    HiRISE images of Mars with ground sampling down to 25 cm/pixel show that the dust-rich mantle covering the surfaces of the Tharsis Montes is organized into ridges whose form and distribution are consistent with formation by aeolian saltation. Other dusty areas near the volcanoes and elsewhere on the planet exhibit a similar morphology. The material composing these "reticulate" bedforms is constrained by their remote sensing properties and the threshold curve combined with the saltation/suspension boundary, both of which vary as a function of elevation (atmospheric pressure), particle size, and particle composition. Considering all of these factors, dust aggregates are the most likely material composing these bedforms. We propose that airfall dust on and near the volcanoes aggregates in situ over time, maybe due to electrostatic charging followed by cementation by salts. The aggregates eventually reach a particle size at which saltation is possible. Aggregates on the flanks are transported downslope by katabatic winds and form linear and "accordion" morphologies. Materials within the calderas and other depressions remain trapped and are subjected to multidirectional winds, forming an interlinked "honeycomb" texture. In many places on and near the volcanoes, light-toned, low thermal inertia yardangs and indurated surfaces are present. These may represent "duststone" formed when aggregates reach a particle size below the threshold curve, such that they become stabilized and subsequently undergo cementation. ?? 2009 Elsevier Inc.

  12. Normal yeast flora of the upper digestive tract of some wild columbids

    USGS Publications Warehouse

    Kocan, R.M.; Hasenclever, H.F.

    1972-01-01

    Seven species of pigeons and doves were cultured for yeasts in the upper digestive tract. The following list gives the isolation rate for each columbid species and the yeasts cultured from them: feral pigeon Columba Livia (Gmelin) 95% -Candida albicans (Robin) Berkhout, C. tropicalis (Castellani) Berkhout, C. krusei (Cast.) Berkhout, C. guilliermondii (Cast.) Langeron et Guerra, Torulopsis glabrata (Anderson) Lodder et De Vries, Saccharomyces telluris Van der Walt, and Geotrichum sp.; white-crowned pigeon (C. leucocephala Linnaeus) 56% -- S. telluris; mourning dove (Zenaidura rnacroura Linnaeus) 24% -- C. albicans, C. tropicalis, C. guilliermondii, and Geotrichurn sp.; passerine ground dove (Collumbigallina passerina Linnaeus) 20% -- C. parapsilosis (Ashford) Langeron et Talice, Kloeckera apiculata (Reess Emend. Klocker) Janke; zenaida dove (Zenaida aurita Temminck) 16% -- C. albicans, C. guilliermondii, and T. glabrata; one moustasche dove (Geotrygon mystacea Gosse) -- C. guillierrnondii; ringed turtle dove (Streptopelia rizoria Linnaeus) 14% -- C. albicans and Geotrichurn sp. No signs of disease could be seen in the 139 birds that were examined, and it was concluded that these yeasts comprise a part of the columbid's normal microbial flora.

  13. Return to Glacier Bay

    USGS Publications Warehouse

    Bodkin, James L.

    2003-01-01

    Seven species of pigeons and doves were cultured for yeasts in the upper digestive tract. The following list gives the isolation rate for each columbid species and the yeasts cultured from them: feral pigeon Columba Livia (Gmelin) 95% -Candida albicans (Robin) Berkhout, C. tropicalis (Castellani) Berkhout, C. krusei (Cast.) Berkhout, C. guilliermondii (Cast.) Langeron et Guerra, Torulopsis glabrata (Anderson) Lodder et De Vries, Saccharomyces telluris Van der Walt, and Geotrichum sp.; white-crowned pigeon (C. leucocephala Linnaeus) 56% -- S. telluris; mourning dove (Zenaidura rnacroura Linnaeus) 24% -- C. albicans, C. tropicalis, C. guilliermondii, and Geotrichurn sp.; passerine ground dove (Collumbigallina passerina Linnaeus) 20% -- C. parapsilosis (Ashford) Langeron et Talice, Kloeckera apiculata (Reess Emend. Klocker) Janke; zenaida dove (Zenaida aurita Temminck) 16% -- C. albicans, C. guilliermondii, and T. glabrata; one moustasche dove (Geotrygon mystacea Gosse) -- C. guillierrnondii; ringed turtle dove (Streptopelia rizoria Linnaeus) 14% -- C. albicans and Geotrichurn sp. No signs of disease could be seen in the 139 birds that were examined, and it was concluded that these yeasts comprise a part of the columbid's normal microbial flora.

  14. Larvicidal Potential of the Halogenated Sesquiterpene (+)-Obtusol, Isolated from the Alga Laurencia dendroidea J. Agardh (Ceramiales: Rhodomelaceae), against the Dengue Vector Mosquito Aedes aegypti (Linnaeus) (Diptera: Culicidae)

    PubMed Central

    Salvador-Neto, Orlando; Gomes, Simone Azevedo; Soares, Angélica Ribeiro; Machado, Fernanda Lacerda da Silva; Samuels, Richard Ian; Nunes da Fonseca, Rodrigo; Souza-Menezes, Jackson; Moraes, Jorge Luiz da Cunha; Campos, Eldo; Mury, Flávia Borges; Silva, José Roberto

    2016-01-01

    Dengue is considered a serious public health problem in many tropical regions of the world including Brazil. At the moment, there is no viable alternative to reduce dengue infections other than controlling the insect vector, Aedes aegypti Linnaeus. In the continuing search for new sources of chemicals targeted at vector control, natural products are a promising alternative to synthetic pesticides. In our work, we investigated the toxicity of a bioactive compound extracted from the red alga Laurencia dendroidea J. Agardh. The initial results demonstrated that crude extracts, at a concentration of 5 ppm, caused pronounced mortality of second instar A. aegypti larvae. Two molecules, identified as (−)-elatol and (+)-obtusol were subsequently isolated from crude extract and further evaluated. Assays with (−)-elatol showed moderate larvicidal activity, whereas (+)-obtusol presented higher toxic activity than (−)-elatol, with a LC50 value of 3.5 ppm. Histological analysis of the larvae exposed to (+)-obtusol revealed damage to the intestinal epithelium. Moreover, (+)-obtusol-treated larvae incubated with 2 µM CM-H2DCFDA showed the presence of reactive oxygen species, leading us to suggest that epithelial damage might be related to redox imbalance. These results demonstrate the potential of (+)-obtusol as a larvicide for use against A. aegypti and the possible mode of action of this compound. PMID:26821032

  15. True bugs (Hemiptera, Heteroptera) as psyllid predators (Hemiptera, Psylloidea)

    PubMed Central

    Jerinić-Prodanović, Dušanka; Protić, Ljiljana

    2013-01-01

    Abstract Data on natural enemies of psyllids are rare and can usually be found in papers about economically significant species. During an investigation of psyllid fauna in Serbia, natural enemies were investigated, too. True bugs were the most numerous among them. From 28 psyllid species, 21 species of true bugs from families Anthocoridae and Miridae were reared. Seven species of Anthocoridae were identified: Anthocoris amplicollis (Horváth, 1839), Anthocoris confusus Reuter, 1884, Anthocoris nemoralis (Fabricius, 1794), Anthocoris nemorum (Linnaeus, 1761), Orius majusculus Reuter, 1884, Orius minutus (Linnaeus, 1758) and Orius niger Wolff, 1811. The following 14 species of Miridae were identified: Atractotomus mali Meyer-Dür, 1843, Campylomma verbasci (Meyer-Dür, 1843), Deraeocoris flavilinea (A. Costa, 1862), Deraeocoris ruber (Linnaeus, 1758), Deraeocoris lutescens (Schilling, 1836), Heterocordylus genistae (Scopoli, 1763), Hypseloecus visci (Puton, 1888), Malacocoris chlorizans Panzer, 1794, Miris striatus (Linnaeus, 1758), Orthotylus marginalis Reuter, 1884, Psallus assimilis Stichel, 1956, Psallus quercus Kirschbaum, 1856, Psallus flavellus Stichel, 1933 and Pseudoloxops coccinea (Meyer-Dür, 1843). The aim of the research was to provide list of true bugs recorded as predators of psyllids in order to preserve their diversity and significance, especially on cultivated plants. PMID:24003311

  16. On the frequency response of a Wenglor particle-counting system for aeolian transport measurements

    NASA Astrophysics Data System (ADS)

    Bauer, Bernard O.; Davidson-Arnott, Robin G. D.; Hilton, Michael J.; Fraser, Douglas

    2018-06-01

    A commonly deployed particle-counting system for aeolian saltation flux, consisting of a Wenglor fork sensor and an Onset Hobo Pulse Input Adapter linked to an Onset Hobo Energy Logger Pro data logger, was tested for frequency response. The Wenglor fork sensor is an optical gate device that has very fast switching capacity that can accommodate the time of flight of saltating sand particles through the sensing volume with the exception of very fine sand or silt and very quickly moving particles. The Pulse Input Adapter, in contrast, imposes limitations on the frequency response of the system. The manufacturer of the pulse adapter specifies an upper limit of 120 Hz, although bench tests with an electronic pulse generator indicate that the frequency response of the Pulse Input Adapter, in isolation, is excellent up to 3000 Hz, with only small error (less than 1.6%) due to under-counting during data transfer intervals. A mechanical test of the integrated system (fork sensor, pulse input adapter, and data logger) demonstrates excellent performance up to about 700 Hz (less than 2% error), but significant under-counting above 1000 Hz for unknown reasons. This specific particle-counting system therefore has a frequency response that is well suited for investigation of the dynamics of aeolian saltation as typically encountered in most field conditions on coastal beaches with the exception of extreme wind events and very small particle sizes.

  17. A COMBINED MODELING AND MEASUREMENT TECHNIQUE FOR ESTIMATING WIND-BLOWN DUST EMISSIONS AT OWENS (DRY) LAKE, CA

    EPA Science Inventory

    A refined method of modeling atmospheric dust concentrations due to wind erosion was developed using real-time saltation flux measurements and ambient dust monitoring data at Owens Lake, California. This modeling method may have practical applications for modeling the atmospheric...

  18. A taxonomic review of the centipede genus Scolopendra Linnaeus, 1758 (Scolopendromorpha, Scolopendridae) in mainland Southeast Asia, with description of a new species from Laos

    PubMed Central

    Siriwut, Warut; Edgecombe, Gregory D.; Sutcharit, Chirasak; Tongkerd, Piyoros; Panha, Somsak

    2016-01-01

    Abstract The centipede genus Scolopendra in mainland Southeast Asia is reviewed taxonomically based on morphological characters, informed by a molecular phylogenetic analysis using sequences from three mitochondrial and nuclear genes (COI, 16S rRNA and 28S rRNA). Eight nominal species of Scolopendra, namely Scolopendra morsitans Linnaeus, 1758, Scolopendra subspinipes Leach, 1816, Scolopendra dehaani Brandt, 1840, Scolopendra multidens Newport, 1844, Scolopendra calcarata Porat, 1876, Scolopendra japonica Koch, 1878, Scolopendra pinguis Pocock, 1891, and Scolopendra dawydoffi Kronmüller, 2012, are redescribed together with some revision of type materials. Geographical variation in each species has been compiled with reference to samples that span their distribution ranges in Southeast Asia and some parts of neighbouring areas such as East Asia, the Indian Ocean, and Africa. Comparative study of traditional taxonomic characters from external morphology provides further information to distinguish some closely related species. Scolopendra cataracta Siriwut, Edgecombe & Panha, sp. n., is described from the southern part of Laos, with additional records in Thailand and Vietnam. The phylogenetic framework for Southeast Asian Scolopendra recognizes Scolopendra calcarata + Scolopendra pinguis, Scolopendra morsitans, and a Scolopendra subspinipes group that unites the other six species as the main clades. Within the Scolopendra subspinipes group, two monophyletic groups can be distinguished by having either slender or short, thick ultimate leg prefemora and different numbers of apical spines on the coxopleuron. Scolopendra arborea Lewis, 1982, is placed in subjective synonymy with Scolopendra dehaani. A survey of external morphology of the genital segments confirms its potential for improving species identification in Scolopendra. Some observations on biology and behaviour are recorded based on field surveys in this area. PMID:27408540

  19. Soil property effects on wind erosion of organic soils

    NASA Astrophysics Data System (ADS)

    Zobeck, Ted M.; Baddock, Matthew; Scott Van Pelt, R.; Tatarko, John; Acosta-Martinez, Veronica

    2013-09-01

    Histosols (also known as organic soils, mucks, or peats) are soils that are dominated by organic matter (OM > 20%) in half or more of the upper 80 cm. Forty two states have a total of 21 million ha of Histosols in the United States. These soils, when intensively cropped, are subject to wind erosion resulting in loss of crop productivity and degradation of soil, air, and water quality. Estimating wind erosion on Histosols has been determined by USDA-Natural Resources Conservation Service (NRCS) as a critical need for the Wind Erosion Prediction System (WEPS) model. WEPS has been developed to simulate wind erosion on agricultural land in the US, including soils with organic soil material surfaces. However, additional field measurements are needed to understand how soil properties vary among organic soils and to calibrate and validate estimates of wind erosion of organic soils using WEPS. Soil properties and sediment flux were measured in six soils with high organic contents located in Michigan and Florida, USA. Soil properties observed included organic matter content, particle density, dry mechanical stability, dry clod stability, wind erodible material, and geometric mean diameter of the surface aggregate distribution. A field portable wind tunnel was used to generate suspended sediment and dust from agricultural surfaces for soils ranging from 17% to 67% organic matter. The soils were tilled and rolled to provide a consolidated, friable surface. Dust emissions and saltation were measured using an isokinetic vertical slot sampler aspirated by a regulated suction source. Suspended dust was sampled using a Grimm optical particle size analyzer. Particle density of the saltation-sized material (>106 μm) was inversely related to OM content and varied from 2.41 g cm-3 for the soil with the lowest OM content to 1.61 g cm-3 for the soil with highest OM content. Wind erodible material and the geometric mean diameter of the surface soil were inversely related to dry clod

  20. New data on Neodiplostomum americanum Chandler and Rausch, 1947 (Digenea: Diplostomidae), in the Great Horned Owl Bubo virginianus Gmelin, 1788 and the Eastern Screech Owl Megascops asio Linnaeus, 1758 in Mississippi, USA.

    PubMed

    Woodyard, Ethan T; Rosser, Thomas G; Griffin, Matt J

    2017-08-01

    Neodiplostomum americanum Chandler and Rausch, 1947 has been reported from six species of owls in North America. At present, there are no molecular data for this species and gene sequence data from Neodiplostomum Railliet, 1919 are limited. A freshly deceased specimen of the Great Horned Owl Bubo virginianus Gmelin, 1788 and a freshly deceased specimen of the Eastern Screech Owl Megascops asio Linnaeus, 1758 were collected in Oktibbeha County, Mississippi in 2014 and 2016, respectively. Neodiplostomum americanum were recovered from both hosts. Herein, updated morphological descriptions are supplemented with gene sequence data from conserved (18S, ITS1-5.8S, ITS2, and 28S rRNA) and fast-evolving (cytochrome c oxidase subunit 1 mtDNA) regions. Preliminary phylogenetic analysis of the genus based on cytochrome c oxidase subunit 1 gene sequence data supports the placement of N. americanum within a discrete phylogroup of the family Diplostomidae. The life history of N. americanum is unknown and currently limited to the description of the adult stage in avian hosts. The molecular data generated in this study offer insight into the phylogenetic placement of N. americanum within the Diplostomatidae and will aid in identifying different life stages in putative intermediate hosts.

  1. Deducing dust emission mechanisms from field measurements

    USDA-ARS?s Scientific Manuscript database

    Field observations are needed to both develop and test theories on dust emission for use in global modeling systems. The mechanism of dust emission (aerodynamic entrainment, saltation bombardment, aggregate disintegration) and the amount and particle-size distribution of emitted dust may vary under ...

  2. Biodegradation of polystyrene wastes in yellow mealworms (larvae of Tenebrio molitor Linnaeus): Factors affecting biodegradation rates and the ability of polystyrene-fed larvae to complete their life cycle.

    PubMed

    Yang, Shan-Shan; Brandon, Anja Malawi; Andrew Flanagan, James Christopher; Yang, Jun; Ning, Daliang; Cai, Shen-Yang; Fan, Han-Qing; Wang, Zhi-Yue; Ren, Jie; Benbow, Eric; Ren, Nan-Qi; Waymouth, Robert M; Zhou, Jizhong; Criddle, Craig S; Wu, Wei-Min

    2018-01-01

    Commercial production of polystyrene (PS) -a persistent plastic that is not biodegradable at appreciable rates in most environments-has led to its accumulation as a major contaminant of land, rivers, lakes, and oceans. Recently, however, an environment was identified in which PS is susceptible to rapid biodegradation: the larval gut of Tenebrio molitor Linnaeus (yellow mealworms). In this study, we evaluate PS degradation capabilities of a previously untested strain of T. molitor and assess its survival and PS biodegradation rates for a range of conditions (two simulated food wastes, three temperatures, seven PS waste types). For larvae fed PS alone, the %PS removed in the short (12-15 h) residence time of the mealworm gut gradually increased for 2-3 weeks then stabilized at values up to 65%. Thirty two-day survival rates were >85% versus 54% for unfed larvae. For mealworms fed ∼10% w/w PS and ∼90% bran, an agricultural byproduct, rates of PS degradation at 25 °C nearly doubled compared to mealworms fed PS alone. Polymer residues in the frass showed evidence of partial depolymerization and oxidation. All of the tested PS wastes degraded, with the less dense foams degrading most rapidly. Mealworms fed bran and PS completed all life cycle stages (larvae, pupae, beetles, egg), and the second generation had favorable PS degradation, opening the door for selective breeding. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Evaporative sodium salt crust development and its wind tunnel derived transport dynamics under variable climatic conditions

    NASA Astrophysics Data System (ADS)

    Nield, Joanna M.; McKenna Neuman, Cheryl; O'Brien, Patrick; Bryant, Robert G.; Wiggs, Giles F. S.

    2016-12-01

    Playas (or ephemeral lakes) can be significant sources of dust, but they are typically covered by salt crusts of variable mineralogy and these introduce uncertainty into dust emission predictions. Despite the importance of crust mineralogy to emission potential, little is known about (i) the effect of short-term changes in temperature and relative humidity on the erodibility of these crusts, and (ii) the influence of crust degradation and mineralogy on wind speed threshold for dust emission. Our understanding of systems where emission is not driven by impacts from saltators is particularly poor. This paper describes a wind tunnel study in which dust emission in the absence of saltating particles was measured for a suite of climatic conditions and salt crust types commonly found on Sua Pan, Botswana. The crusts were found to be non-emissive under climate conditions characteristic of dawn and early morning, as compared to hot and dry daytime conditions when the wind speed threshold for dust emission appears to be highly variable, depending upon salt crust physicochemistry. Significantly, sodium sulphate rich crusts were found to be more emissive than crusts formed from sodium chloride, while degraded versions of both crusts had a lower emission threshold than fresh, continuous crusts. The results from this study are in agreement with in-situ field measurements and confirm that dust emission from salt crusted surfaces can occur without saltation, although the vertical fluxes are orders of magnitude lower (∼10 μg/m/s) than for aeolian systems where entrainment is driven by particle impact.

  4. A new depositional model for sand-rich loess on the Buckley Flats outwash plain, northwestern Lower Michigan

    NASA Astrophysics Data System (ADS)

    Nyland, Kelsey E.; Schaetzl, Randall J.; Ignatov, Anthony; Miller, Bradley A.

    2018-04-01

    Loess was first studied in Michigan on the Buckley Flats, where outwash, overlain by ≈70 cm of loamy sediment, was originally interpreted as loess mixed with underlying sands. This paper re-evaluates this landscape through a spatial analysis of data from auger samples and soil pits. To better estimate the loamy sediment's initial textures, we utilized "filtered" laser diffraction data, which remove much of the coarser sand data. Textures of filtered silt data for the loamy sediment are similar to loess. The siltiest soils are found in the low-relief, central part of the Flats. Spatial analyses revealed that many silt fractions are nearly uniformly distributed, suggesting that the loess was not derived from a single source. The previous depositional model for the loamy mantle relied on loessfall followed by pedoturbation, but does not explain (1) the variation in sand contents across the Flats, or (2) the abrupt contact below the loamy mantle. This contact suggests that the outwash was frozen when the sediments above were deposited. Deep gullies at the western margins of the Flats were likely cut as permafrost facilitated runoff. Our new model for the origin of the loamy mantle suggests that the sands on the uplands were generated from eroding gullies and saltated onto the uplands along with loess that fell more widely. Sands saltating to the west of the Flats may have entrained some silts, facilitating loessfall downwind. At most sites, the loamy mantle gets increasingly silty near the surface, suggesting that saltation ended before loess deposition.

  5. Can dust emission mechanisms be determined from field measurements?

    USDA-ARS?s Scientific Manuscript database

    Field observations are needed to develop and test theories on dust emission for use in dust modeling systems. The dust emission mechanism (aerodynamic entrainment, saltation bombardment, aggregate disintegration) as well as the amount and particle-size distribution of emitted dust may vary under sed...

  6. Disentangling dust emission mechanisms – a field study

    USDA-ARS?s Scientific Manuscript database

    Field observations are needed to both develop and test theories on dust emission for use in global modeling systems. The dust emission mechanism (aerodynamic entrainment, saltation bombardment, aggregate disintegration) as well as the amount and particle-size distribution of emitted dust may vary un...

  7. Morphological diversity of microstructures occurring in selected recent bivalve shells and their ecological implications

    NASA Astrophysics Data System (ADS)

    Brom, Krzysztof Roman; Szopa, Krzysztof

    2016-12-01

    Environmental adaptation of molluscs during evolution has led to form biomineral exoskeleton - shell. The main compound of their shells is calcium carbonate, which is represented by calcite and/or aragonite. The mineral part, together with the biopolymer matrix, forms many types of microstructures, which are differ in texture. Different types of internal shell microstructures are characteristic for some bivalve groups. Studied bivalve species (freshwater species - duck mussel (Anodonta anatina Linnaeus, 1758) and marine species - common cockle (Cerastoderma edule Linnaeus, 1758), lyrate Asiatic hard clam (Meretrix lyrata Sowerby II, 1851) and blue mussel (Mytilus edulis Linnaeus, 1758)) from different locations and environmental conditions, show that the internal shell microstructure with the shell morphology and thickness have critical impact to the ability to survive in changing environment and also to the probability of surviving predator attack. Moreover, more detailed studies on molluscan structures might be responsible for create mechanically resistant nanomaterials.

  8. Karyotypic diversity in four species of the genus Gymnotus Linnaeus, 1758 (Teleostei, Gymnotiformes, Gymnotidae): physical mapping of ribosomal genes and telomeric sequences

    PubMed Central

    Scacchetti, Priscilla Cardim; Pansonato-Alves, José Carlos; Utsunomia, Ricardo; Oliveira, Claudio; Foresti, Fausto

    2011-01-01

    Abstract Conventional (Giemsa, C-Banding, Ag-NORs, CMA3) and molecular (5S rDNA, 18S rDNA, telomeric sequences) cytogenetic studies were carried out in specimens of ten distinct fish populations of the genus Gymnotus (Gymnotus sylvius Albert and Fernandes-Matioli, 1999, Gymnotus inaequilabiatus Valenciennes, 1839, Gymnotus pantherinus Steindachner, 1908, and G. cf. carapo Linnaeus, 1758) from different Brazilian hydrographic basins. Gymnotus sylvius presented a diploid number of 40 chromosomes (22m+12sm+6st), Gymnotus pantherinus presented 52 chromosomes (32m+18sm+2st), while Gymnotus inaequilabiatus (42m+10sm+2a)and Gymnotus cf. carapo (38m+12sm+4st) presented 54 chromosomes. The C-banding technique revealed centromeric marks in all chromosomes of all species. Besides that, conspicuous blocks of heterochromatin were found interstitially on the chromosomes of Gymnotus inaequilabiatus, Gymnotus cf. carapo,and Gymnotus pantherinus. All four species showed single nucleolus organizing regions confirmed by results obtained through Ag-NORs and FISH experiments using 18S rDNA probes, which showed the NORs localized on the first chromosome pair in Gymnotus inaequilabiatus, Gymnotus cf. carapo,and Gymnotus pantherinus, and on pair 2 in Gymnotus sylvius. CMA3 staining revealed additional unrelated NORs marks in Gymnotus sylvius and Gymnotus pantherinus. The 5S rDNA probes revealed signals on one pair in Gymnotus sylvius and two pairs in Gymnotus pantherinus; Gymnotus inaequilabiatus had about seventeen pairs marked, and Gymnotus cf. carapo had about fifteen pairs marked. It is considered that the high amount of heterochromatin identified in the chromosomes of Gymnotus inaequilabiatus and Gymnotus cf. carapo could have facilitated the dispersion of 5S rDNA in these species. Interstitial signals were detected on the first metacentric pair of Gymnotus sylvius by telomeric probes (TTAGGG)n indicating the possible occurrence of chromosomal fusions in this species. The present

  9. Devonian (Emsian-Eifelian) fish from the Lower Bokkeveld Group (Ceres Subgroup), South Africa

    NASA Astrophysics Data System (ADS)

    Anderson, M. E.; Almond, J. E.; Evans, F. J.; Long, J. A.

    1999-07-01

    Four major groups of fish are represented by fragmentary remains from South Africa's Lower Bokkeveld Group of Early to Middle Devonian age: the Acanthodii, Chondrichthyes, Placodermi and Osteichthyes. These represent the oldest known occurrences of these groups in southern Africa, as well as an important addition to the very meagre record of earlier Devonian fish from the Malvinokaffric Province of southwestern Gondwana. Bokkeveld fish material comes from the Gydo (Late Emsian) and Tra Tra (Middle Eifelian) Formations of the Western Cape and Eastern Cape Provinces. The cosmopolitan marine acanthodian Machæracanthus is represented only by isolated fin spines which may belong to two different species on the basis of their external ornamentation, cross-sectional outline and internal histology. The elasmobranchs are represented by four elements: (1) a flattened chondrocranium which bears affinity to the Late Devonian-Carboniferous symmoriid (protacrodont) 'cladodont' sharks. It is probably the earliest known (Emsian) shark chondrocranium; (2) an isolated, primitive scapulocoracoid with a very short coracoidal ridge; (3) ankylosed and isolated radials, interpreted as parts of pterygial plates of a paired fin of an unknown chondrichthyan bearing affinity to the Middle Devonian Zamponiopteron from Bolivia; and (4) isolated barlike structures, perhaps gill arch or a jaw elements, thought to be from the same taxon as (3). The placoderms are represented by an incomplete trunk armour and fragmentary, finely ornamented plates of a primitive antiarch. The Osteichthyes are represented by a single large scale of an unidentified dipnoan from the Eifelian of the Cedarberg range, as well as a probable sarcopterygian dermal plate from the Emsian of the Prince Albert area. These are among the earliest sarcopterygian remains recorded from the Malvinokaffric Province.

  10. Juvenile bottlenecks and salinity shape grey mullet assemblages in Mediterranean estuaries

    NASA Astrophysics Data System (ADS)

    Cardona, Luis; Hereu, Bernat; Torras, Xavier

    2008-05-01

    Previous research has suggested that competitive bottlenecks may exist for the Mediterranean grey mullets (Osteichthyes, Mugilidae) at the fry stage with the exotic Cyprinus carpio (Osteichthyes, Cyprinidae) playing a central role. As a consequence, the structure of grey mullet assemblages at later stages is thought to reflect previous competition as well as differences in osmoregulatory skills. This paper tests that hypothesis by examining four predictions about the relative abundance of five grey mullet species in 42 Western Mediterranean estuary sites from three areas (Aiguamolls de l'Empordà, Ebro Delta and Minorca) differing in the salinity level and occurrence of C. carpio. Field data confirmed the predictions as: (1) Liza aurata and Mugil cephalus were scarce everywhere and never dominated the assemblage; (2) Liza saliens dominated the assemblage where the salinity level was higher than 13; (3) Liza ramado always dominated the assemblage where the salinity level was lower than 13 and C. carpio was present; and (4) Chelon labrosus dominated the assemblage only where the salinity level was lower than 13 and C. carpio was absent. The catch per unit effort of C. labrosus of any size was smaller in the presence of C. carpio than where it had not been introduced, which is in agreement with the juvenile competitive bottleneck hypothesis. Discriminant analysis confirmed that the assemblage structure was linked to the salinity level and the occurrence of C. carpio for both early juveniles and late juveniles as well as adults. The data reported here reveal that the structure of grey mullet assemblages inhabiting Mediterranean estuaries is determined by salinity and competitive interactions at the fry stage.

  11. Grain transport mechanics in shallow flow

    USDA-ARS?s Scientific Manuscript database

    A physical model based on continuum multiphase flow is described to represent saltating transport of grains in shallow overland flows. The two-phase continuum flow of water and sediment considers coupled St.Venant type equations. The interactive cumulative effect of grains is incorporated by a dispe...

  12. Grain transport mechanics in shallow overland flow

    USDA-ARS?s Scientific Manuscript database

    A physical model based on continuum multiphase flow is described to represent saltating transport of grains in shallow overland flow. The two phase continuum flow of water and sediment considers coupled St.Venant type equations. The interactive cumulative effect of grains is incorporated by a disper...

  13. Erosion

    USDA-ARS?s Scientific Manuscript database

    Erosion is the detachment of soil particles and transportation to another location. Wind erosion occurs when wind speed exceeds a critical threshold level, and loose soil particles or soil particles removed by abrasion then move in one of three ways: creep, saltation, and suspension. Erosion by wate...

  14. Threshold wind velocity dynamics as a driver of aeolian sediment mas flux

    USDA-ARS?s Scientific Manuscript database

    Horizontal (saltation) mass flux is a key driver of aeolian dust emission. Estimates of the horizontal mass flux underpin assessments of the global dust budget and influence our understanding of the dust cycle and its interactions. Current equations for predicting horizontal mass flux are based on l...

  15. A preliminary assessment of the Titan planetary boundary layer

    NASA Technical Reports Server (NTRS)

    Allison, Michael

    1992-01-01

    Results of a preliminary assessment of the characteristic features of the Titan planetary boundary are addressed. These were derived from the combined application of a patched Ekman surface layer model and Rossby number similarity theory. Both these models together with Obukhov scaling, surface speed limits and saltation are discussed. A characteristic Akman depth of approximately 0.7 km is anticipated, with an eddy viscosity approximately equal to 1000 sq cm/s, an associated friction velocity approximately 0.01 m/s, and a surface wind typically smaller than 0.6 m/s. Actual values of these parameters probably vary by as much as a factor of two or three, in response to local temporal variations in surface roughness and stability. The saltation threshold for the windblown injection of approximately 50 micrometer particulates into the atmosphere is less than twice the nominal friction velocity, suggesting that dusty breezes might be an occassional feature of the Titan meteorology.

  16. [Alcoholism-a study by Carl von Linnes in "Nemesis Divina"].

    PubMed

    Ojesjö, Leif

    2007-01-01

    Linnaeus' (1707- 1778) anecdotes in Nemesis Divina and stories from the Lundby Study were taken as a starting point for this essay an about the fate of heavy ("gluttonous") drinkers. The narratives are real enough, even if their meanings are interpreted as highly metaphorical. It is argued that through Linnaeus thinking on diet, alcohol, excessive appetites and God's revenge, today's secular awareness of risk behavior and unhealthy life styles may be expanded. Hence, new insights can grow from different perspectives on complicated problems.

  17. [The specificity of blastocysts (Rhizopoda: Lobosea)].

    PubMed

    Belova, L M; Krylov, M V

    1994-01-01

    The analysis of specificity of blastocysts was based on the data on host association and on experimental data. In experiments we failed to infect the geese (Anser anser) with Blastocystis galli taken from the fowl (Gallus gallus) and also failed to infect the fowl with B. suis taken from the pigs (Sus scrofa domestica). Experimental data and field observations of blastocysts distribution among different groups of hosts point out that the same species of blastocysts can not parasitize in hosts belonging to different classes and orders. The examination of 89 fish specimens belonging to 14 species of Osteichthyes taken from the Neman delta did not discover any blastocysts.

  18. First observations of histopathological effects of 2,4,6-trinitrotoluene (TNT) in gills of European eel Anguilla anguilla (Linnaeus, 1758): histopathological effects of 2,4,6-trinitrotoluene in gills of European eel.

    PubMed

    Sensini, Cristiana; Della Torre, Camilla; Corsi, Ilaria; Focardi, Silvano

    2008-12-01

    The aim of the present study was to investigate the effects on gill morphology of the explosive 2,4,6-trinitrotoluene (TNT) in a model fish, the European eel, Anguilla anguilla (Linnaeus, 1758) to assess potential detrimental effects in marine fish due to its presence in dumping areas. Juvenile specimens of A. anguilla were exposed in vivo for 6 and 24 h to 0.5, 1 and 2.5 mg/l nominal concentrations of TNT using dimethyl sulfoxide (0.1 per thousand) as solvent carrier. Histological analysis of gills indicated that TNT induced several structural lesions. After 6h of exposure at 0.5 and 1 mg/l TNT, oedema of some secondary lamellae was evident: this change at the highest dose of 2.5 mg/l led to epithelial lifting and detachment from the endothelium and rupture of the branchial membrane and vascular congestion. After 24 h at 0.5 mg/l, increased oedema in secondary lamellae, extensive epithelial detachment and vascular congestion and dilation of lamellar capillaries and pooling of blood at 1 mg/l were observed. At 2.5 mg/l, epithelial hyperplasia, fusion of adjacent lamellae, obliteration of interlamellar spaces by means of tight junctions were also observed. Moreover, chloride cells proliferated along secondary lamellae, and mucus hypersecretion was evident. The overall results clearly indicate that gills are sensitive targets of TNT.

  19. Preliminary results of dust emission data from Yellow Lake Playa, West Texas, USA

    USDA-ARS?s Scientific Manuscript database

    We investigated the relationship between groundwater and dust emission rates at Yellow Lake, a saline “wet” playa in West Texas with a long history of wind erosion. Deflation of the playa surface has generated lunettes composed of silt-clay aggregates and gypsum. Saltation sensors indicate that most...

  20. Bone morphology of the hind limbs in two caviomorph rodents.

    PubMed

    de Araújo, F A P; Sesoko, N F; Rahal, S C; Teixeira, C R; Müller, T R; Machado, M R F

    2013-04-01

    In order to evaluate the hind limbs of caviomorph rodents a descriptive analysis of the Cuniculus paca (Linnaeus, 1766) and Hydrochoerus hydrochaeris (Linnaeus, 1766) was performed using anatomical specimens, radiography, computed tomography (CT) and full-coloured prototype models to generate bone anatomy data. The appendicular skeleton of the two largest rodents of Neotropical America was compared with the previously reported anatomical features of Rattus norvegicus (Berkenhout, 1769) and domestic Cavia porcellus (Linnaeus, 1758). The structures were analyzed macroscopically and particular findings of each species reported. Features including the presence of articular fibular projection and lunulae were observed in the stifle joint of all rodents. Imaging aided in anatomical description and, specifically in the identification of bone structures in Cuniculus paca and Hydrochoerus hydrochaeris. The imaging findings were correlated with the anatomical structures observed. The data may be used in future studies comparing these animals to other rodents and mammalian species. © 2012 Blackwell Verlag GmbH.

  1. Talitrid amphipods (Crustacea) as biomonitors for copper and zinc

    NASA Astrophysics Data System (ADS)

    Rainbow, P. S.; Moore, P. G.; Watson, D.

    1989-06-01

    Data are presented on the copper and zinc concentrations of four talitrid amphipod species (standard dry weight 10 mg), i.e. Orchestia gammarellus (Pallas), O. mediterranea Costa, Talitrus saltator Montagu and Talorchestia deshayesii (Audouin), from 31 sites in S.W. Scotland, N. Wales and S.W. England. More limited data are also presented for cadmium in O. gammarellus (three sites) and T. deshayesii (one site). In S.W. Scotland, copper concentrations were raised significantly in O. gammarellus from Whithorn and Auchencairn (Solway) and Loch Long and Holy Loch (Clyde). In S.W. England, copper concentrations were highest at Restronguet Creek, Torpoint and Gannel (Cornwall). Samples of O. gammarellus from Islay (inner Hebrides) taken adjacent to the effluent outfalls of local whisky distilleries fell into two groups based on copper concentrations (presumably derived from copper stills), the higher copper levels deriving from the more productive distilleries. High copper levels were found in T. saltator and Tal. deshayesii from Dulas Bay (Wales). Zinc levels in O. gammarellus were high in Holy Loch and Auchencairn (Scotland), Gannel and Torpoint (England) but extremely elevated (as was Zn in O. mediterranea) at Restronguet Creek. Zinc was also high in T. saltator from Dulas Bay (Wales), but not in Tal. deshayesii. Cadmium levels in O. gammarellus from Kilve (Bristol Channel) were much raised. These differences (a) conform with expectations of elevated bioavailability of these metals from well researched areas (S.W. England & N. Wales), and (b) identify hitherto unappreciated areas of enrichment in S.W. Scotland. Orchestia gammarellus is put forward as a suitable biomonitor for copper and zinc in British coastal waters.

  2. Dust Emissions from Undisturbed and Disturbed, Crusted Playa Surfaces: Cattle Trampling Effect

    NASA Astrophysics Data System (ADS)

    Zobeck, T. M.; Baddock, M. C.; van Pelt, R.; Fredrickson, E. L.

    2009-12-01

    Dry playa lake beds can be a significant source of fine dust emissions during high wind events in arid and semiarid landscapes. The physical and chemical properties of the playa surface control the amount and properties of the dust emitted. In this study, we use a field wind tunnel to quantify the dust emissions from a bare, fine-textured playa surface located in the Chihuahua Desert at the Jornada Experimental Range, near Las Cruces, New Mexico, USA. We tested natural, undisturbed crusted surfaces and surfaces that had been subjected to two levels of domestic animal disturbance. The animal disturbance was provided by trampling produced from one and ten passes along the length of the wind tunnel by a 630 kg Angus-Hereford cross cow. The trampling broke the durable crust and created loose erodible material. Each treatment (natural crust, one pass, and ten passes) was replicated three times. A push-type wind tunnel with a 6 m long, 0.5 m wide, and 1 m high test section was used to generate dust emissions under controlled conditions. Clean medium sand was dropped onto the playa surface to act as an abrader material. The tunnel wind speed was equivalent to 15 m/s at a height of 2 m over a smooth soil surface. The tunnel was initially run for ten minutes, with no abrader added. A second 30 minute run was subsequently sampled as abrader was added to the wind stream. Dust and saltating material were collected using an isokinetic slot sampler at the end of the tunnel. Total airborne dust was collected on two 25 cm x 20 cm glass fiber filters (GFF) and measured using a GRIMM particle monitor every 6 sec throughout each test run. Disturbance by trampling generated increased saltating material and airborne dust. The amount of saltating material measured during the initial (no abrader added) run was approximately 70% greater and 5.8 times the amount of saltating material measured on the one pass and ten pass plots, respectively, compared with that observed on the undisturbed

  3. Detection of carboxylesterase and esterase activity in culturable gut bacterial flora isolated from diamondback moth, Plutella xylostella (Linnaeus), from India and its possible role in indoxacarb degradation.

    PubMed

    Ramya, Shanivarsanthe Leelesh; Venkatesan, Thiruvengadam; Srinivasa Murthy, Kottilingam; Jalali, Sushil Kumar; Verghese, Abraham

    2016-01-01

    Diamondback moth (DBM), Plutella xylostella (Linnaeus), is a notorious pest of brassica crops worldwide and is resistant to all groups of insecticides. The insect system harbors diverse groups of microbiota, which in turn helps in enzymatic degradation of xenobiotic-like insecticides. The present study aimed to determine the diversity of gut microflora in DBM, quantify esterase activity and elucidate their possible role in degradation of indoxacarb. We screened 11 geographic populations of DBM in India and analyzed them for bacterial diversity. The culturable gut bacterial flora underwent molecular characterization with 16S rRNA. We obtained 25 bacterial isolates from larvae (n=13) and adults (n=12) of DBM. In larval gut isolates, gammaproteobacteria was the most abundant (76%), followed by bacilli (15.4%). Molecular characterization placed adult gut bacterial strains into three major classes based on abundance: gammaproteobacteria (66%), bacilli (16.7%) and flavobacteria (16.7%). Esterase activity from 19 gut bacterial isolates ranged from 0.072 to 2.32μmol/min/mg protein. Esterase bands were observed in 15 bacterial strains and the banding pattern differed in Bacillus cereus - KC985225 and Pantoea agglomerans - KC985229. The bands were characterized as carboxylesterase with profenofos used as an inhibitor. Minimal media study showed that B. cereus degraded indoxacarb up to 20%, so it could use indoxacarb for metabolism and growth. Furthermore, esterase activity was greater with minimal media than control media: 1.87 versus 0.26μmol/min/mg protein. Apart from the insect esterases, bacterial carboxylesterase may aid in the degradation of insecticides in DBM. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  4. Populations and home range relationships of the box turtle, Terrapene c. carolina (Linnaeus)

    USGS Publications Warehouse

    Stickel, L.F.

    1950-01-01

    SUMMARY: A population study of the box turtle (Terrapene c. carolina Linnaeus) was made during the years 1944 to 1947 at the Patuxent Research Refuge, Maryland. A thirty acre area in well drained bottomland forest on the flood plain of the Patuxent River was selected for intensive study. Similarly forested land extended in all directions from the study plot. Markers were established at eighty-three foot intervals over the study plot for reference in recording locality data. Individuals were marked by filing notches in the marginal scutes according to a code system. There were 2109 collections of study area turtles. Records of collecting sites and turtle behavior showed that in the bottomlands habitat cover is utilized extensively during the day as well as at night. Turtles not actively moving about are almost always found in or around brush piles, heaps of debris, and tangles of vines and briars. Gully banks and woods openings are used for sunning. Turtles are occasionally found in the mud or water of the gullies. The commonest type of night retreat is a cavity constructed by the turtle in leaves, debris, or earth. These cavities, termed 'forms,' may be used only once, but are sometimes used repeatedly, often at intervals of several days or more. Different turtles sometimes use the same form on successive nights. Weather conditions most favorable to turtle activity are high humidity, warm sunny days, and frequent rains. The most unfavorable influences are low temperatures and drought. On most summer days there are some active turtles but individual turtles are not active every day. Periods of activity are alternated with periods of quiet even in favorable weather. This behavior is most pronounced in early spring and late fall when inactive days are often more numerous than active ones. Adult turtles occupy specific home ranges which they maintain from year to year. The turtles living in the study plot retained their ranges even through a flood that completely

  5. Total and cytosolic concentrations of twenty metals/metalloids in the liver of brown trout Salmo trutta (Linnaeus, 1758) from the karstic Croatian river Krka.

    PubMed

    Dragun, Zrinka; Filipović Marijić, Vlatka; Krasnići, Nesrete; Ivanković, Dušica; Valić, Damir; Žunić, Jakov; Kapetanović, Damir; Smrzlić, Irena Vardić; Redžović, Zuzana; Grgić, Ivana; Erk, Marijana

    2018-01-01

    Total and cytosolic concentrations of twenty metals/metalloids in the liver of brown trout Salmo trutta (Linnaeus, 1758) were studied in the period from April 2015 to May 2016 at two sampling sites on Croatian river Krka, to establish if river water contamination with metals/metalloids downstream of Knin town has influenced metal bioaccumulation in S. trutta liver. Differences were observed between two sites, with higher concentrations of several elements (Ag, As, Ca, Co, Na, Se, Sr, V) found downstream of Knin town, whereas few others (Cd, Cs, Mo, Tl) were, unexpectedly, increased at the Krka River spring. However, total metal/metalloid concentrations in the liver of S. trutta from both sites of the Krka River were still mainly below previously reported levels for pristine freshwaters worldwide. The analysis of seasonal changes of metal/metalloid concentrations in S. trutta liver and their association with fish sex and size mostly indicated their independence of fish physiology, making them good indicators of water contamination and exposure level. Metal/metalloid concentrations in the metabolically available hepatic cytosolic fractions reported in this study are the first data of that kind for S. trutta liver, and the majority of analyzed elements were present in the cytosol in the quantity higher than 50% of their total concentrations, thus indicating their possible availability for toxic effects. However, the special attention should be directed to As, Cd, Cs, and Tl, which under the conditions of increased exposure tended to accumulate more within the cytosol. Although metal/metalloid concentrations in S. trutta liver were still rather low, monitoring of the Krka River water quality and of the health status of its biota is essential due to a trend of higher metal/metalloid bioaccumulation downstream of Knin town, especially taking into consideration the proximity of National Park Krka and the need for its conservation. Copyright © 2017 Elsevier Inc. All

  6. Aeolian transport of biota with dust: A wind tunnel experiment

    NASA Astrophysics Data System (ADS)

    Rivas, J. A., Jr.; Gill, T. E.; Van Pelt, R. S.; Walsh, E.

    2015-12-01

    Ephemeral wetlands are ideal sources for dust emission, as well as repositories for dormant stages of aquatic invertebrates. An important component of invertebrate dispersal and colonization to new areas is the ability to be entrained into the atmosphere. Aquatic invertebrate eggs fall within the size of dust and sand grains (30-600μm), are less dense and aerodynamically shaped. We have shown previously that aquatic invertebrates can be dispersed long distances in dust storms but the extent of transport of taxa based on diapausing egg size/morphology has not been investigated. Here, we control the wind erosion process in a wind tunnel to test entrainment of diapausing stages of brine shrimp, clam shrimp, tadpole shrimp, fairy shrimp, Daphnia, and the rotifers Brachionus plicatilis and B. calyciflorus into the air by saltation. Diapausing eggs were mixed with sterilized wind-erodible soil. The soil/egg mixture was moistened with distilled water and air dried to form a crust. Dust was generated in a wind tunnel by releasing sand grains that act as saltator material similar to wind-entrained natural sands. Maximum wind velocity was 10m/s and entrained particles were sampled through an isokinetic horizontal intake opening. Aeolian sediment was collected from three points in the system; transfer section for coarse sediment, the pan subtending a settling chamber for finer saltation-sized sediment, and two paper filters for suspension-sized sediment. Samples were then passed through 250 and 350 μm sieves to remove abrader sand and rehydrated with various sterile media depending on the type of organism. We retrieved viable brine, fairy, and tadpole shrimp, ostracods, Daphnia, and diapausing eggs of the rotifers after hydration. This experiment demonstrates that resting stages of many invertebrates can be wind-eroded due to size and egg morphology and remain viable under controlled conditions mimicking dust emission.

  7. Analysis of wind-blown sand movement over transverse dunes.

    PubMed

    Jiang, Hong; Huang, Ning; Zhu, Yuanjian

    2014-12-01

    Wind-blown sand movement often occurs in a very complicated desert environment where sand dunes and ripples are the basic forms. However, most current studies on the theoretic and numerical models of wind-blown sand movement only consider ideal conditions such as steady wind velocity, flat sand surface, etc. In fact, the windward slope gradient plays a great role in the lift-off and sand particle saltation. In this paper, we propose a numerical model for the coupling effect between wind flow and saltating sand particles to simulate wind-blown sand movement over the slope surface and use the SIMPLE algorithm to calculate wind flow and simulate sands transport by tracking sand particle trajectories. We furthermore compare the result of numerical simulation with wind tunnel experiments. These results prove that sand particles have obvious effect on wind flow, especially that over the leeward slope. This study is a preliminary study on windblown sand movement in a complex terrain, and is of significance in the control of dust storms and land desertification.

  8. Analysis of Wind-blown Sand Movement over Transverse Dunes

    PubMed Central

    Jiang, Hong; Huang, Ning; Zhu, Yuanjian

    2014-01-01

    Wind-blown sand movement often occurs in a very complicated desert environment where sand dunes and ripples are the basic forms. However, most current studies on the theoretic and numerical models of wind-blown sand movement only consider ideal conditions such as steady wind velocity, flat sand surface, etc. In fact, the windward slope gradient plays a great role in the lift-off and sand particle saltation. In this paper, we propose a numerical model for the coupling effect between wind flow and saltating sand particles to simulate wind-blown sand movement over the slope surface and use the SIMPLE algorithm to calculate wind flow and simulate sands transport by tracking sand particle trajectories. We furthermore compare the result of numerical simulation with wind tunnel experiments. These results prove that sand particles have obvious effect on wind flow, especially that over the leeward slope. This study is a preliminary study on windblown sand movement in a complex terrain, and is of significance in the control of dust storms and land desertification. PMID:25434372

  9. Clinostomum complanatum and Clinostomum marginatum (Rudolphi, 1819) (Digenea: Clinostomidae) are separate species based on differences in ribosomal DNA.

    PubMed

    Dzikowski, R; Levy, M G; Poore, M F; Flowers, J R; Paperna, I

    2004-04-01

    Infections by metacercariae of Clinostomum (Leidy, 1856) species adversely affect aquacultured fish and are potentially transmissible to humans. Molecular methodologies are efficient tools, which enable diagnosis of all life-history stages of trematodes in their diverse hosts. The small subunit of ribosomal DNA genes of adults of the Old World Clinostomum complanatum (Rudolphi, 1819) and the New World Clinostomum marginatum (Rudolphi, 1819), obtained from a little egret Egretta garzetta (Linnaeus, 1766) and the great blue heron Ardea herodias (Linnaeus, 1758), respectively, were amplified, sequenced, and aligned. The resulting alignment was used to develop a genetic assay to differentiate between these species.

  10. In silico reconstitution of Listeria propulsion exhibits nano-saltation.

    PubMed

    Alberts, Jonathan B; Odell, Garrett M

    2004-12-01

    To understand how the actin-polymerization-mediated movements in cells emerge from myriad individual protein-protein interactions, we developed a computational model of Listeria monocytogenes propulsion that explicitly simulates a large number of monomer-scale biochemical and mechanical interactions. The literature on actin networks and L. monocytogenes motility provides the foundation for a realistic mathematical/computer simulation, because most of the key rate constants governing actin network dynamics have been measured. We use a cluster of 80 Linux processors and our own suite of simulation and analysis software to characterize salient features of bacterial motion. Our "in silico reconstitution" produces qualitatively realistic bacterial motion with regard to speed and persistence of motion and actin tail morphology. The model also produces smaller scale emergent behavior; we demonstrate how the observed nano-saltatory motion of L. monocytogenes,in which runs punctuate pauses, can emerge from a cooperative binding and breaking of attachments between actin filaments and the bacterium. We describe our modeling methodology in detail, as it is likely to be useful for understanding any subcellular system in which the dynamics of many simple interactions lead to complex emergent behavior, e.g., lamellipodia and filopodia extension, cellular organization, and cytokinesis.

  11. Animal and human rabies in Mongolia.

    PubMed

    Odontsetseg, N; Uuganbayar, D; Tserendorj, Sh; Adiyasuren, Z

    2009-12-01

    The prevalence of animal rabies differs in each area of Mongolia. Wolves (Canis lupus Linnaeus, 1758), foxes ( Vulpes vulpes Linnaeus, 1758), corsac foxes (Vulpes corsac Linnaeus, 1768) and manuls (Felis manul Pallas, 1778) are considered to be the infective wild animals in natural foci. Amongst livestock, cattle have had the most rabies cases, followed by camels, sheep, goats and horses. The peak prevalence of animal rabies occurred in the 1970s. Dundgovi Province had the highest incidence during that period. The number of rabies cases in animals decreased during the 1980s. This may have been due to a decrease in the number of wild reservoir animals and the improvement of appropriate veterinary measures. In recent years, animal rabies has prevailed in the Khangai and western provinces. The infection source of most human rabies cases is the dog. In order to minimise the incidence of human rabies, canine vaccination programmes need to be improved. This paper describes the epizootiology and epidemiology of animal and human rabies in Mongolia. It describes rabies control programmes, including diagnosis, conducted in Mongolia in an effort to control the disease.

  12. New tick records in Rondônia, Western Brazilian Amazon.

    PubMed

    Labruna, Marcelo Bahia; Barbieri, Fábio Silva; Martins, Thiago Fernandes; Brito, Luciana Gatto; Ribeiro, Francisco Dimas Sales

    2010-01-01

    In the present study, we provide new tick records from Vilhena Municipality, in the Southeast of the State of Rondônia, Northern Brazil. Ticks collected from a capybara, Hydrochoerus hydrochaeris (Linnaeus), were identified as Amblyomma romitii Tonelli-Rondelli (1 female), and Amblyomma sp. (1 larva). Ticks collected from a harpy eagle, Harpia harpyja (Linnaeus), were identified as Amblyomma cajennense (Fabricius) (16 nymphs) and Haemaphysalis juxtakochi Cooley (1 nymph). Ticks collected from a yellow-footed tortoise, Chelonoidis denticulada (Linnaeus), were identified as Amblyomma rotundatum Koch (10 females, 2 nymphs), and Amblyomma sp. (2 larvae). The present record of A. romitii is the first in the State of Rondônia, and represents the southernmost record for this tick species, indicating that its distribution area is much larger than currently recognized. Although both A. cajennense and H. juxtakochi have been reported parasitizing various bird species, we provide the first tick records on a harpy eagle. A. rotundatum is widespread in the State of Rondônia, and has been previously reported on the yellow-footed tortoise. The present records increase the tick fauna of Rondônia to 26 species.

  13. 7 CFR 360.200 - Designation of noxious weeds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... mantegazzianum Sommier & Levier (giant hogweed) Homeria spp. Imperata brasiliensis Trinius (Brazilian satintail) Imperata cylindrica (Linnaeus) Raeuschel (cogongrass) Ischaemum rugosum Salisbury (murainograss) Leptochloa...

  14. Biochemistry of fish stomach chitinase.

    PubMed

    Ikeda, Mana; Kakizaki, Hiromi; Matsumiya, Masahiro

    2017-11-01

    Fish are reported to exhibit chitinase activity in the stomach. Analyses of fish stomach chitinases have shown that these enzymes have the physiological function of degrading chitinous substances ingested as diets. Osteichthyes, a group that includes most of the fishes, have several chitinases in their stomachs. From a phylogenetic analysis of the chitinases of vertebrates, these particular molecules were classified into a fish-specific group and have different substrate specificities, suggesting that they can degrade ingested chitinous substances efficiently. On the other hand, it has been suggested that coelacanth (Sarcopterygii) and shark (Chondrichthyes) have a single chitinase enzyme in their stomachs, which shows multiple functions. This review focuses on recent research on the biochemistry of fish stomach chitinases. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. No evidence of interference competition among the invasive feral pig and two native peccary species in a Neotropical wetland

    USGS Publications Warehouse

    Oliveira-Santos, Luiz G. R.; Dorazio, Robert M.; Tomas, Walfrido M.; Mourao, Guilherme; Fernandez, Fernando A.S.

    2011-01-01

    In South America, the invasive feral pig (Sus scrofa Linnaeus) has become established in Argentina, Uruguay, Paraguay and in a wide range within Brazil, along the southern half of the Atlantic Forest, in the cerrado (savanna) and in the Pantanal wetland. The geographical ranges of the two most common South American native peccary (Tayassu pecari Link and Pecari tajacu Linnaeus) overlap almost entirely, and the feral pig now co-occurs with them in several areas. Because feral pig, white-lipped and collared peccary are considered ecological equivalents, there has been much speculation about possible competitive interactions among them (Desbiez et al. 2009, Sicuro & Oliveira 2002).

  16. Dasypodidae Borner, 1919 (Insecta, Hymenoptera): Proposed emendation of spelling to Dasypodaidae, so removing the homonymy with Dasypodidae Gray, 1821 (Mammalia, Xenarthra)

    USGS Publications Warehouse

    Alexander, B.A.; Michener, C.D.; Gardner, A.L.

    1998-01-01

    The family-group name DASYPODIDAE Borner, 1919 (Insecta, Hymenoptera) is a junior homonym Of DASYPODIDAE Gray, 1821 (Mammalia, Xenarthra). It is proposed that the homonymy between the two names, which relate to short-tongued bees and armadillos respectively, should be removed by emending the stem of the generic name Dasypoda Latreille, 1802, on which the insect familygroup name is based, to give DASYPODAIDAE, while leaving the mammalian name (based on Dasypus Linnaeus, 1758) unchanged. Dasypus novemcinctus Linnaeus, 1758, the type species of Dasypus, has a wide distribution in the southern United States, Central and South America. The genus Dasypoda ranges throughout most of the Palearctic region.

  17. Measurements of the Coefficient of Restitution of Quartz Sand on Basalt: Implications for Abrasion Rates on Earth and Mars

    NASA Technical Reports Server (NTRS)

    Banks, M.; Bridges, N. T.; Benzit, M.

    2005-01-01

    Knowledge of the rates at which rocks abrade from the impact of saltating sand provides important input into estimating the age and degree of modification of arid surfaces on Earth and Mars. Previous work has relied on measuring mass loss rates in the field and the laboratory. The susceptibility of rocks and other natural materials has been quantified on a relative scale from laboratory studies.

  18. Production of reactive oxygen species from abraded silicates. Implications for the reactivity of the Martian soil

    NASA Astrophysics Data System (ADS)

    Bak, Ebbe N.; Zafirov, Kaloyan; Merrison, Jonathan P.; Jensen, Svend J. Knak; Nørnberg, Per; Gunnlaugsson, Haraldur P.; Finster, Kai

    2017-09-01

    The results of the Labeled Release and the Gas Exchange experiments conducted on Mars by the Viking Landers show that compounds in the Martian soil can cause oxidation of organics and a release of oxygen in the presence of water. Several sources have been proposed for the oxidizing compounds, but none has been validated in situ and the cause of the observed oxidation has not been resolved. In this study, laboratory simulations of saltation were conducted to examine if and under which conditions wind abrasion of silicates, a process that is common on the Martian surface, can give rise to oxidants in the form of hydrogen peroxide (H2O2) and hydroxyl radicals (ṡOH). We found that silicate samples abraded in simulated Martian atmospheres gave rise to a significant production of H2O2 and ṡOH upon contact with water. Our experiments demonstrated that abraded silicates could lead to a production of H2O2 facilitated by atmospheric O2 and inhibited by carbon dioxide. Furthermore, during simulated saltation the silicate particles became triboelectrically charged and at pressures similar to the Martian surface pressure we observed glow discharges. Electrical discharges can cause dissociation of CO2 and through subsequent reactions lead to a production of H2O2. These results indicate that the reactions linked to electrical discharges are the dominant source of H2O2 during saltation of silicates in a simulated Martian atmosphere, given the low pressure and the relatively high concentration of CO2. Our experiments provide evidence that wind driven abrasion could enhance the reactivity of the Martian soil and thereby could have contributed to the oxidation of organic compounds and the O2 release observed in the Labeled Release and the Gas Exchange experiments. Furthermore, the release of H2O2 and ṡOH from abraded silicates could have a negative effect on the persistence of organic compounds in the Martian soil and the habitability of the Martian surface.

  19. Development of mandibular, hyoid and hypobranchial muscles in the zebrafish: homologies and evolution of these muscles within bony fishes and tetrapods

    PubMed Central

    Diogo, Rui; Hinits, Yaniv; Hughes, Simon M

    2008-01-01

    Background During vertebrate head evolution, muscle changes accompanied radical modification of the skeleton. Recent studies have suggested that muscles and their innervation evolve less rapidly than cartilage. The freshwater teleostean zebrafish (Danio rerio) is the most studied actinopterygian model organism, and is sometimes taken to represent osteichthyans as a whole, which include bony fishes and tetrapods. Most work concerning zebrafish cranial muscles has focused on larval stages. We set out to describe the later development of zebrafish head muscles and compare muscle homologies across the Osteichthyes. Results We describe one new muscle and show that the number of mandibular, hyoid and hypobranchial muscles found in four day-old zebrafish larvae is similar to that found in the adult. However, the overall configuration and/or the number of divisions of these muscles change during development. For example, the undivided adductor mandibulae of early larvae gives rise to the adductor mandibulae sections A0, A1-OST, A2 and Aω, and the protractor hyoideus becomes divided into dorsal and ventral portions in adults. There is not always a correspondence between the ontogeny of these muscles in the zebrafish and their evolution within the Osteichthyes. All of the 13 mandibular, hyoid and hypobranchial muscles present in the adult zebrafish are found in at least some other living teleosts, and all except the protractor hyoideus are found in at least some extant non-teleost actinopterygians. Of these muscles, about a quarter (intermandibularis anterior, adductor mandibulae, sternohyoideus) are found in at least some living tetrapods, and a further quarter (levator arcus palatini, adductor arcus palatini, adductor operculi) in at least some extant sarcopterygian fish. Conclusion Although the zebrafish occupies a rather derived phylogenetic position within actinopterygians and even within teleosts, with respect to the mandibular, hyoid and hypobranchial muscles it

  20. Isolation and cross-familial amplification of 41 microsatellites for the brook charr (Salvelinus fontinalis)

    USGS Publications Warehouse

    Perry, G.M.L.; King, T.L.; St. -Cyr, J.; Valcourt, M.; Bernatchez, L.

    2005-01-01

    The brook charr (Salvelinus fontinalis; Osteichthyes: Salmonidae) is a phenotypically diverse fish species inhabiting much of North America. But relatively few genetic diagnostic resources are available for this fish species. We isolated 41 microsatellites from S. fontinalis polymorphic in one or more species of salmonid fish. Thirty-seven were polymorphic in brook charr, 15 in the congener Arctic charr (Salvelinus alpinus) and 14 in the lake charr (Salvelinus namaycush). Polymorphism was also relatively high in Oncorhynchus, where 21 loci were polymorphic in rainbow trout (Oncorhynchus mykiss) and 16 in cutthroat trout (Oncorhynchus clarkii) but only seven and four microsatellite loci were polymorphic in the more distantly related lake whitefish (Coregonus clupeaformis) and Atlantic salmon (Salmo salar), respectively. One duplicated locus (Sfo228Lav) was polymorphic at both duplicates in S. fontinalis. ?? 2005 Blackwell Publishing Ltd.

  1. Immunogenic activity of the fish tapeworm Pterobothrium heteracanthum (Trypanorhyncha: Pterobothriidae) in BALB/c mice.

    PubMed

    Mattos, D P B G; Verícimo, M A; Lopes, L M S; São Clemente, S C

    2015-03-01

    The aim of this study was to verify the immunogenicity of Pterobothrium heteracanthum (Cestoda: Trypanorhyncha) crude protein extract (PH-CPE) in BALB/c mice. The parasites were obtained from Micropogonias furnieri (Osteichthyes: Sciaenidae). Groups of six mice were each immunized with 10, 50 or 100 μg of PH-CPE, on days 0 and 35. Both specific IgG and IgE responses were developed after immunization. The immunoblot assay revealed that specific IgG recognizes PH-CPE proteins with two molecular weight ranges, 60-75 and 30-40 kDa, and that IgE recognizes larger proteins over 120 kDa. This appears to be the first report on the immunogenicity of metacestodes within the Pterobothriidae and that PH-CPE is a potential inducer of a specific IgE response.

  2. Information visualization courses for students with a computer science background.

    PubMed

    Kerren, Andreas

    2013-01-01

    Linnaeus University offers two master's courses in information visualization for computer science students with programming experience. This article briefly describes the syllabi, exercises, and practices developed for these courses.

  3. New Titan Saltation Threshold Experiments: Investigating Current and Past Climates

    NASA Astrophysics Data System (ADS)

    Bridges, N.; Burr, D. M.; Marshall, J.; Smith, J. K.; Emery, J. P.; Horst, S. M.; Nield, E.; Yu, X.

    2015-12-01

    Titan exhibits aeolian sand dunes that cover ~20% of its surface, attesting to significant sediment transport by the wind. Recent experiments in the Titan Wind Tunnel (TWT) at NASA Ames Research Center [1,2] found that the threshold friction speed needed to detach Titanian "sand" is about 50% higher than previous estimates based on theory alone [3], a result that might be explained by the low ratio of particle to fluid density on the body [1]. Following the successful completion of the initial Titan threshold tests, we are conducting new experiments that expand the pressure range above and below current Titan values. The basic experimental techniques are described in [1], with minor updates to the instrumentation as described in [2]. To reproduce the kinematic viscosity and particle friction Reynolds number equivalent to that expected for Titan's nitrogen atmosphere at 1.4 bars and 94 K requires that TWT be pressurized to 12.5 bars for air at 293K. In addition to running experiments at this pressure to reproduce previous results [1] and investigate low density (high density ratio) materials, TWT pressures of 3 and 8 bars are in the experimental matrix to understand threshold under past Titan conditions when the atmospheric pressure may have been lower [4]. Higher pressures, at 15 and 20 bars in TWT, are also being run to understand the putative effects of low density ratio conditions. Our experimental matrix for this follow-on work uses some of the same materials as previously used, including walnut shells, basalt, quartz, glass spheres, and various low density materials to better simulate the gravity-equivalent weight of Titan sand. For these experiments, the TWT is now equipped with a new high pressure Tavis transducer with sufficient sensitivity to measure freestream speeds of less than 0.5 m s-1 at 12.5 bars. New techniques include video documentation of the experiments. We are also investigating methods of measuring humidity of the wind tunnel environment and electrostatic forces to assess their effect on threshold. [1] Burr, D.M. et al. [2015], Nature, 517, 60-67. [2] Burr, D.M. et al. [2015], Aeolian Res., in press [3] Iversen, J.D. and B.R. White (1982), Sedimentology, 29, 111-119. [4] Charnay, B. et al. [2014], Icarus, 241, 269-279.

  4. Bedload and Total Load Sediment Transport Equations for Rough Open-Channel Flow

    NASA Astrophysics Data System (ADS)

    Abrahams, A. D.; Gao, P.

    2001-12-01

    The total sediment load transported by an open-channel flow may be divided into bedload and suspended load. Bedload transport occurs by saltation at low shear stress and by sheetflow at high shear stress. Dimensional analysis is used to identify the dimensionless variables that control the transport rate of noncohesive sediments over a plane bed, and regression analysis is employed to isolate the significant variables and determine the values of the coefficients. In the general bedload transport equation (i.e. for saltation and sheetflow) the dimensionless bedload transport rate is a function of the dimensionless shear stress, the friction factor, and an efficiency coefficient. For sheetflow the last term approaches 1, so that the bedload transport rate becomes a function of just the dimensionless shear stress and the friction factor. The dimensional analysis indicates that the dimensionless total load transport rate is a function of the dimensionless bedload transport rate and the dimensionless settling velocity of the sediment. Predicted values of the transport rates are graphed against the computed values of these variables for 505 flume experiments reported in the literature. These graphs indicate that the equations developed in this study give good unbiased predictions of both the bedload transport rate and total load transport rate over a wide range of conditions.

  5. Three-dimensional simulation of the motion of a single particle under a simulated turbulent velocity field

    NASA Astrophysics Data System (ADS)

    Moreno-Casas, P. A.; Bombardelli, F. A.

    2015-12-01

    A 3D Lagrangian particle tracking model is coupled to a 3D channel velocity field to simulate the saltation motion of a single sediment particle moving in saltation mode. The turbulent field is a high-resolution three dimensional velocity field that reproduces a by-pass transition to turbulence on a flat plate due to free-stream turbulence passing above de plate. In order to reduce computational costs, a decoupled approached is used, i.e., the turbulent flow is simulated independently from the tracking model, and then used to feed the 3D Lagrangian particle model. The simulations are carried using the point-particle approach. The particle tracking model contains three sub-models, namely, particle free-flight, a post-collision velocity and bed representation sub-models. The free-flight sub-model considers the action of the following forces: submerged weight, non-linear drag, lift, virtual mass, Magnus and Basset forces. The model also includes the effect of particle angular velocity. The post-collision velocities are obtained by applying conservation of angular and linear momentum. The complete model was validated with experimental results from literature within the sand range. Results for particle velocity time series and distribution of particle turbulent intensities are presented.

  6. On Release of Microbe-Laden Particles from Mars Landers

    NASA Technical Reports Server (NTRS)

    Bellan, Josette; Harstad, Kenneth

    2006-01-01

    A paper presents a study in which rates of release of small particles from Mars lander spacecraft into the Martian atmosphere were estimated from first principles. Because such particles can consist of, or be laden with, terrestrial microbes, the study was undertaken to understand their potential for biological contamination of Mars. The study included taking account of forces and energies involved in adhesion of particles and of three mechanisms of dislodgement of particles from the surface of a Mars lander: wind shear, wind-driven impingement of suspended dust, and impingement of wind-driven local saltating sand particles. Wind shear was determined to be effective in dislodging only particles larger than about 10 microns and would probably be of limited interest because such large particles could be removed by pre-flight cleaning of the spacecraft, and their number on the launched spacecraft would thus be relatively small. Dislodgement by wind-driven dust was found to be characterized by an adhesion half-life of the order of 10,000 years judged to be too long to be of concern. Dislodgement by saltating sand particles, including skirts of dust devils, was found to be of potential importance, depending on the sizes of the spacecraft-attached particles and characteristics of both Mars sand-particle and spacecraft surfaces.

  7. Simulation model of erosion and deposition on a barchan dune

    NASA Technical Reports Server (NTRS)

    Howard, A. D.; Morton, J. B.; Gal-El-hak, M.; Pierce, D. B.

    1977-01-01

    Erosion and deposition over a barchan dune near the Salton Sea, California, are modeled by bookkeeping the quantity of sand in saltation following streamlines of transport. Field observations of near surface wind velocity and direction plus supplemental measurements of the velocity distribution over a scale model of the dune are combined as input to Bagnold type sand transport formulas corrected for slope effects. A unidirectional wind is assumed. The resulting patterns of erosion and deposition compare closely with those observed in the field and those predicted by the assumption of equilibrium (downwind translation of the dune without change in size or geometry). Discrepancies between the simulated results and the observed or predicted erosional patterns appear to be largely due to natural fluctuations in the wind direction. The shape of barchan dunes is a function of grain size, velocity, degree of saturation of the oncoming flow, and the variability in the direction of the oncoming wind. The size of the barchans may be controlled by natural atmospheric scales, by the age of the dunes, or by the upwind roughness. The upwind roughness can be controlled by fixed elements or by sand in the saltation. In the latter case, dune scale is determined by grain size and wind velocity.

  8. An olfactory shift is associated with male perfume differentiation and species divergence in orchid bees.

    PubMed

    Eltz, Thomas; Zimmermann, Yvonne; Pfeiffer, Carolin; Pech, Jorge Ramirez; Twele, Robert; Francke, Wittko; Quezada-Euan, J Javier G; Lunau, Klaus

    2008-12-09

    Saltational changes may underlie the diversification of pheromone communication systems in insects, which are normally under stabilizing selection favoring high specificity in signals and signal perception. In orchid bees (Euglossini), the production of male signals depends on the sense of smell: males collect complex blends of volatiles (perfumes) from their environment, which are later emitted as pheromone analogs at mating sites. We analyzed the behavioral and antennal response to perfume components in two male morphotypes of Euglossa cf. viridissima from Mexico, which differ in the number of mandibular teeth. Tridentate males collected 2-hydroxy-6-nona-1,3-dienyl-benzaldehyde (HNDB) as the dominant component of their perfume. In bidentate males, blends were broadly similar but lacked HNDB. Population genetic analysis revealed that tri- and bidentate males belong to two reproductively isolated lineages. Electroantennogram tests (EAG and GC-EAD) showed substantially lower antennal responses to HNDB in bidentate versus tridentate males, revealing for the first time a mechanism by which closely related species acquire different chemical compounds from their habitat. The component-specific differences in perfume perception and collection in males of two sibling species are in agreement with a saltational, olfaction-driven mode of signal perfume evolution. However, the response of females to the diverged signals remains unknown.

  9. Field sampling of loose erodible material: A new method to consider the full particle-size range

    NASA Astrophysics Data System (ADS)

    Klose, Martina; Gill, Thomas E.

    2017-04-01

    The aerodynamic entrainment of sand and dust is determined by the atmospheric forces exerted onto the soil surface and by the soil-surface condition. If aerodynamic forces are strong enough to generate sand and dust lifting, the entrained sediment amount still critically depends on the supply of loose particles readily available for lifting. This loose erodible material (LEM) is sometimes defined as the thin layer of loose particles on top of a crusted surface. Here, we more generally define LEM as loose particles or particle aggregates available for entrainment, which may or may not overlay a soil crust. Field sampling of LEM is difficult and only few attempts have been made. Motivated by saltation as the most efficient process to generate dust emission, methods have focused on capturing LEM in the sand-size range or on determining the potential of a soil surface to be eroded by aerodynamic forces and particle impacts. Here, our focus is to capture the full particle-size distribution of LEM in situ, including the dust and sand-size range, to investigate the potential and likelihood of dust emission mechanisms (aerodynamic entrainment, saltation bombardment, aggregate disintegration) to occur. A new vacuum method is introduced and its capability to sample LEM without significant alteration of the LEM particle-size distribution is investigated.

  10. Pterobothrium crassicolle parasitizing Paralichthys orbignyanus (Osteichthyes, Paralichthyidae) in Brazil.

    PubMed

    Felizardo, Nilza N; Knoff, Marcelo; Diniz, Jessica B; Torres, Eduardo J L; Calixto, Flávia A A; Clemente, Sérgio C São

    2018-01-01

    From September 2014 to November 2015, 30 Paralichthys orbignyanus specimens were obtained from Sepetiba Bay in the municipality of Rio de Janeiro, State of Rio de Janeiro, Brazil. The fishes were necropsied and cestode larvae were recovered from the abdominal cavity, mesentery, and serosas of the stomach, intestine, spleen, liver, kidney and gonads. Nineteen fish were parasitized by a total of 90 trypanorhynch plerocerci. Based on morphological characters, these were identified as Pterobothrium crassicolle. The parasitism indices for P. crassicolle on P. orbignyanus, were 63.3% for prevalence, 4.7 for mean intensity, 3 for mean abundance and 1 to 18 for range of infection. These parasites were studied due to their importance during fish sanitary inspection, if one considers the harm that the repulsive aspect of infected fish may cause to consumers. This is the first record of P. crassicolle plerocerci parasitizing P. orbignyanus.

  11. 7 CFR 301.45 - Notice of quarantine; restriction on interstate movement of specified regulated articles.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... prevent the spread of the gypsy moth, Lymantria dispar (Linnaeus), a dangerous insect injurious to forests and shade trees and not theretofore widely prevalent or distributed within or throughout the United...

  12. 7 CFR 301.45 - Notice of quarantine; restriction on interstate movement of specified regulated articles.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... prevent the spread of the gypsy moth, Lymantria dispar (Linnaeus), a dangerous insect injurious to forests and shade trees and not theretofore widely prevalent or distributed within or throughout the United...

  13. 7 CFR 301.45 - Notice of quarantine; restriction on interstate movement of specified regulated articles.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... prevent the spread of the gypsy moth, Lymantria dispar (Linnaeus), a dangerous insect injurious to forests and shade trees and not theretofore widely prevalent or distributed within or throughout the United...

  14. 7 CFR 301.45 - Notice of quarantine; restriction on interstate movement of specified regulated articles.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... prevent the spread of the gypsy moth, Lymantria dispar (Linnaeus), a dangerous insect injurious to forests and shade trees and not theretofore widely prevalent or distributed within or throughout the United...

  15. 7 CFR 301.45 - Notice of quarantine; restriction on interstate movement of specified regulated articles.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... prevent the spread of the gypsy moth, Lymantria dispar (Linnaeus), a dangerous insect injurious to forests and shade trees and not theretofore widely prevalent or distributed within or throughout the United...

  16. LADEE Search for a Dust Exosphere: A Historical Perspective

    NASA Technical Reports Server (NTRS)

    Glenar, D. A.; Stubbs, T. J.; Elphic, R.

    2014-01-01

    The LADEE search for exospheric dust is strongly motivated by putative detections of forward-scattered sunlight from exospheric dust grains which were observed during the Apollo era. This dust population, if it exists, has been associated with charging and transport of dust near the terminators. It is likely that the concentration of these dust grains is governed by a saltation mechanism originated by micrometeoroid impacts, which are the source of the more tenuous ejecta cloud.

  17. Oviposition Deterrent and Larvicidal and Pupaecidal Activity of Seven Essential Oils and their Major Components against Culex quinquefasciatus Say (Diptera: Culicidae): Synergism–antagonism Effects

    PubMed Central

    Andrade-Ochoa, Sergio; Sánchez-Aldana, Daniela; Chacón-Vargas, Karla Fabiola; Rivera-Chavira, Blanca E.; Camacho, Alejandro D.; Nogueda-Torres, Benjamín

    2018-01-01

    The larvicidal activity of essential oils cinnamon (Cinnamomum verum J. Presl), Mexican lime (Citrus aurantifolia Swingle) cumin (Cuminum cyminum Linnaeus), clove (Syzygium aromaticum (L.) Merr. & L.M.Perry), laurel (Laurus nobilis Linnaeus), Mexican oregano (Lippia berlandieri Schauer) and anise (Pimpinella anisum Linnaeus)) and their major components are tested against larvae and pupae of Culex quinquefasciatus Say. Third instar larvae and pupae are used for determination of lethality and mortality. Essential oils with more than 90% mortality after a 30-min treatment are evaluated at different time intervals. Of the essential oils tested, anise and Mexican oregano are effective against larvae, with a median lethal concentration (LC50) of 4.7 and 6.5 µg/mL, respectively. Anise essential oil and t-anethole are effective against pupae, with LC50 values of 102 and 48.7 µg/mL, respectively. Oregano essential oil and carvacrol also have relevant activities. A kinetic analysis of the larvicidal activity, the oviposition deterrent effect and assays of the effects of the binary mixtures of chemical components are undertaken. Results show that anethole has synergistic effects with other constituents. This same effect is observed for carvacrol and thymol. Limonene shows antagonistic effect with β-pinene. The high larvicidal and pupaecidal activities of essential oils and its components demonstrate that they can be potential substitutes for chemical compounds used in mosquitoes control programs. PMID:29443951

  18. 77 FR 53236 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-31

    ... 154-Botany Bay to conduct a review of their management plans. The Antarctic Support Contract (ASC..., ASPA 137-Northwest White Island, ASPA 138-Linnaeus Terrace, and, ASPA 154-Botany Bay. Dates August 15...

  19. Effects of highway runoff on streamflow and water quality in the Sevenmile Creek basin, a rural area in the Piedmont Province of North Carolina, July 1981 to July 1982

    USGS Publications Warehouse

    Harned, Douglas

    1988-01-01

    cadmium concentrations frequently exceeded the maximum levels recommended by the EPA for drinking water. The highway is a source of contaminants to surrounding areas. Particulate and metal loads in dustfall and chemical-constituent concentrations in soils decrease exponentially with distance from the highway. The highest concentrations of contaminants were found on the downwind side. Increased concentrations of metals (cadmium, chromium, iron, lead, nickel, and zinc) in rainfall were observed in samples collected near the highway and in samples collected approximately one-half mile away. Material loading due to dustfall was greater than loading due to rainfall. Loading due to saltated particles, those heavier particles bounced along the highway surface, was higher than loading due to dustfall. Saltation loads were greatest during the winter months because of highway deicing and sanding, which supplied an estimated two-thirds of the saltated materials. The remaining one-third of the saltated load came primarily from the deposition of particles from vehicles. Some of the greatest constituent concentrations were measured in the soil water sampled from the lysimeters located adjacent to the highway.

  20. Status of the new genera in Gistel’s “Die Insecten-Doubletten aus der Sammlung des Herrn Grafen Rudolph von Jenison Walworth” issued in 1834

    PubMed Central

    Bousquet, Yves; Bouchard, Patrice

    2017-01-01

    proposed: Ocys [Aleochara nigra Gravenhorst, 1802; Staphylinidae], Hydatobia [Staphylinus impressus Olivier, 1795; Staphylinidae], Hedonius [Elater noctilucus Linnaeus, 1758; Elateridae], Charmionus [Elater porcatus Linnaeus, 1767; Elateridae], Epaphius [Dasytes variegatus Germar, 1823; Melyridae], Geophilus [Scarabeus asper Fabricius, 1775; Scarabaeidae], Atrimedeus [Scarabaeus punctatus Villers, 1789; Scarabaeidae], Polycarmes [Melolontha villosa Fabricius, 1781; Scarabaeidae], Cecrops [Tenebrio gigas Linnaeus, 1763; Tenebrionidae], Pythonissus [Helops morio Fabricius, 1777; Tenebrionidae], Ceratades [Cerambyx sutor Linnaeus, 1758; Cerambycidae]. The following genus-group names are declared nomina oblita [nomina protecta in square brackets]: Berecyntha [Aulacochilus Chevrolat, 1836; Erotylidae], Ceraunus [Golofa Hope, 1837; Scarabaeidae], Atrimedeus [Pentodon Hope, 1837; Scarabaeidae], Eupalus [Temnorhynchus Hope, 1837; Scarabaeidae], Pelops [Prionychus Solier, 1835; Tenebrionidae]. PMID:29134025

  1. 11. Photocopy of 1906 photograph. Glass negative in Paul A. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Photocopy of 1906 photograph. Glass negative in Paul A. Kohl's office, Missouri Botanical Garden. CLOSE VIEW OF LINNAEUS BUST - Missouri Botanical Garden, Linnaean House, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

  2. Demodex lutrae n. sp. (Acari) in European otter Lutra lutra (Carnivora: Mustelidae) with data from other demodecid mites in carnivores.

    PubMed

    Izdebska, Joanna N; Rolbiecki, Leszek

    2014-12-01

    This article describes morphological characteristics and occurrence of Demodex lutrae n. sp., which was found on European otter Lutra lutra (Linnaeus, 1758) in Poland. The new species was found in hairy regions of otter skin, mainly in the head area. With respect to morphological features, D. lutrae is most similar to D. canis (Leydig, 1859) from the domestic dog Canis familiaris Linnaeus, 1758. The new species is a medium-sized demodecid mite (adult stages average 200 μm in length); characteristic features of these mites are hammer-shaped supracoxal spines (setae elc.p) on dorsal side of gnathosoma and palps with 3 conical spines. Demodex lutrae is the first representative of the family Demodecidae described in a host from the subfamily Lutrinae. This paper also contains a checklist of demodecid mites known from carnivores.

  3. The effect of dust lifting process on the electrical properties of the atmosphere

    NASA Astrophysics Data System (ADS)

    Esposito, Francesca; Molinaro, Roberto; Ionut Popa, Ciprian; Molfese, Cesare; Cozzolino, Fabio; Marty, Laurent; Taj-Eddine, Kamal; Di Achille, Gaetano; Silvestro, Simone; Ori, Gian Gabriele

    2015-04-01

    Airborne dust and aerosol particles affect climate by absorbing and scattering thermal and solar radiation and acting as condensation nuclei for the formation of clouds. So, they strongly influence the atmospheric thermal structure, balance and circulation. On Earth and Mars, this 'climate forcing' is one of the most uncertain processes in climate change predictions. Wind-driven blowing of sand and dust is also responsible for shaping planetary surfaces through the formation of sand dunes and ripples, the erosion of rocks, and the creation and transport of soil particles. These processes are not confined to Earth, but occur also on Mars, Venus and Titan. It is clear that the knowledge of the atmospheric dust properties and the mechanisms of dust settling and raising into the atmosphere are important to understand planetary climate and surface evolution. On Mars the physical processes responsible for dust injection into the atmosphere are still poorly understood, but they likely involve saltation as on Earth. Saltation is a process where large sand grains are forced by the wind to move in ballistic trajectories on the soil surface. During these hops they hit dust particles, that are well bound to the soil due to interparticle cohesive forces, thus transferring to them the momentum necessary to be entrained into the atmosphere. Recently, it has been shown that this process is also responsible to generate strong electric fields in the atmosphere up to 100-150 kV/m. This enhanced electric force acts as a feedback in the dust lifting process, lowering the threshold of the wind friction velocity u* necessary to initiate sand saltation. It is an important aspect of dust lifting process that need to be well characterized and modeled. Even if literature reports several measurements of E-fields in dust devils events, very few reports deal with atmospheric electric properties during dust storms or isolated gusts. We present here preliminary results of an intense field test

  4. Effect of the particle to fluid density ratio on bedform development: An application of PTV

    NASA Astrophysics Data System (ADS)

    McKenna Neuman, C. L.; Gordon, M. D.

    2009-05-01

    The particle to fluid density ratio plays a key role in sediment transport and strongly governs the relative importance of the transport mode. In aeolian systems, this ratio is three orders of magnitude larger than for the transport of sedimentary particles in water, such that saltation is the dominant mode for diameters (250 microns) commonly found in ripples and dunes. The partitioning of fluid momentum to saltators, and therefore to the surface upon impact, is extremely important to the entrainment of sediment, the maintenance of transport, and the scaling of aeolian bedforms. This paper demonstrates the use of Particle Tracking Velocimetry in measuring the partitioning of momentum associated with particle collisions on beds of quartz sand (2630 kg m-3) typical of aeolian dunes, and acrylic particles (1210 kg m-3) similar to blowing snow (920 kg m-3). The experiments were carried out in the boundary layer wind tunnel at Trent University on full beds that were 13.8 m in length and 0.71 m in width. In the majority of experiments, the wind speeds were either at or just above the threshold for saltation so that we could distinguish discrete particle trajectories. Surface ripples formed in the majority of experiments and passed through the camera's field of view so that the height, length and rate of migration could be measured in relation to the distributions of particle impact speed and angle, as well as those for the number, speed and angle of the particles ejected. Although similar in height, the ripples comprised of acrylic particles were 2 to 4 times longer, much more asymmetric, and migrated significantly faster than those in sand. The particle impact and ejection speeds were very similar, although the sand particles approached and left the bed at substantially larger angles than observed for the lighter acrylic particles of similar diameter. In a separate experiment, glass beads were flung onto each bed material at 4 ms-1 in still air. It was discovered that

  5. 10. Photocopy of January 10, 1906 photograph. Glass negative in ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Photocopy of January 10, 1906 photograph. Glass negative in Paul A. Kohl's office, Missouri Botanical Garden. BUST OF LINNAEUS OVER SOUTH ENTRANCE - Missouri Botanical Garden, Linnaean House, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

  6. The melliferous potential of forest and meadow plant communities on Mount Tara (Serbia).

    PubMed

    Jarić, Snežana; Mačukanović-Jocić, Marina; Mitrović, Miroslava; Pavlović, Pavle

    2013-08-01

    The apiflora of 34 forest and meadow plant communities in Tara National Park was studied with the aim of assessing their melliferous potential and their contribution to bee pasture during the vegetation period. The melliferous plants were analyzed individually from the aspect of their flowering phenology, abundance, and the intensity of nectar and pollen production, as well as the production of honeydew. The melliferous potential of each investigated plant community was theoretically assessed on the basis of the coenotic coefficient of melliferousness incorporating a phytocoenotic analysis, the coenotic coefficients of nectar and pollen production, and the percentage of melliferous species in relation to the total number of species that characterize the association. The highest percentage of the melliferous species was noted in the meadow association Petasitetum hybridi (70%) and the forest association Piceetum-Abietis serpentinicum (63.6%). The highest values of the coenotic coefficient of melliferousness were established for the forest association Querco-Carpinetum iliricum, and the meadow association Rhinantho-Cynosuretum cristati. Trees notable for their honeydew production in good quantities were Pinus nigra Arnold, Picea sp. Fagus sylvatica Linnaeus, Populus tremula Linnaeus, and Quercus cerris Linnaeus. Because, the vegetation in the study area is forest dominated, forest bee pasture including early flowering herbaceous and woody plants, is of the greatest significance for the honey bee, both in the early spring because of pollen and nectar production, and in the autumn as a source of honeydew.

  7. "A great complication of circumstances"--Darwin and the economy of nature.

    PubMed

    Pearce, Trevor

    2010-01-01

    In 1749, Linnaeus presided over the dissertation "Oeconomia Naturae," which argued that each creature plays an important and particular role in nature's economy. This phrase should be familiar to readers of Darwin, for he claims in the Origin that "all organic beings are striving, it may be said, to seize on each place in the economy of nature." Many scholars have discussed the influence of political economy on Darwin's ideas. In this paper, I take a different tack, showing that Darwin's idea of an economy of nature stemmed from the views of earlier naturalists like Linnaeus and Lyell. I argue, in the first section of the paper, that Linnaeus' idea of oeconomia naturae is derived from the idea of the animal economy, and that his idea of politia naturae is an extension of the idea of a politia civitatis. In the second part, I explore the use of the concept of stations in the work of De Candolle and Lyell - the precursor to Darwin's concept of places. I show in the third part of the paper that the idea of places in an economy of nature is employed by Darwin at many key points in his thinking: his discussion of the Galapagos birds, his reading of Malthus, etc. Finally, in the last section, I demonstrate that the idea of a place in nature's economy is essential to Darwin's account of divergence. To tell his famous story of divergence and adaptation, Darwin needed the economy of nature.

  8. Linnaean sources and concepts of orchids.

    PubMed

    Jarvis, Charlie; Cribb, Phillip

    2009-08-01

    Linnaeus developed a robust system for naming plants and a useful, if mechanical, system for classifying them. His binomial nomenclature proved the catalyst for the rapid development of our knowledge of orchids, with his work on the family dating back to 1737 in the first edition of his Genera Plantarum. His first work devoted to orchids, indeed the first monograph of the family, was published in 1740 and formed the basis for his account in Species Plantarum, published in 1753, in which he gave a binomial name to each species. Given the overwhelming number of orchids, he included surprisingly few - only 62 mostly European species - in Species Plantarum, his seminal work on the plants of the world. This reflects the European origin of modern botany and the concentration of extra-European exploration on other matters, such as conquest, gold and useful plants. Nevertheless, the scope of Linnaeus' work is broad, including plants from as far afield as India, Japan, China and the Philippines to the east, and eastern Canada, the West Indies and northern South America to the west. In his later publications he described and named a further 45 orchids, mostly from Europe, South Africa and the tropical Americas. The philosophical basis of Linnaeus' work on orchids is discussed and his contribution to our knowledge of the family assessed. His generic and species concepts are considered in the light of current systematic ideas, but his adoption of binomial nomenclature for all plants is his lasting legacy.

  9. Phenomena of drag reduction on saltating sediment in shallow, supercritical flows

    USDA-ARS?s Scientific Manuscript database

    ABSTRACT: When a group of objects move through a fluid, it often exhibits coordinated behavior in which bodies in the wake of a leader generally experience reduced drag. Locomotion provides well known examples including the maneuvering and clustering of racing automobiles and bicyclists and queuing...

  10. Aeolian processes aboard a space station: Saltation and particle trajectory analysis

    NASA Technical Reports Server (NTRS)

    White, B. R.; Greeley, R.; Iversen, J. D.; Leach, R. N.

    1986-01-01

    The Carousel wind tunnel (CWT) proposed to study aeolian processes aboard a space station consists of two concentric rotating drums. The space between the two drums comprises the wind tunnel test section. Differential rates of rotation of the two drums would provide a wind velocity with respect to either drum surface. Preliminary results of measured velocity profiles made in a CWT prototype indicate that the wall bounded boundary layer profiles are suitable to simulate flat plate turbulent boundary layer flow. The two dimensional flat plate Cartesian coordinate equations of motion of a particle moving through the air are explained. In order to assess the suitability of CWT in the analysis of the trajectories of windblown particles, a series of calculations were conducted comparing cases for gravity with those of zero gravity. Results from the calculations demonstrate that a wind tunnel of the carousel design could be fabricted to operate in a space station environment and that experiments could be conducted which would yield significant results contributing to the understanding of the physics of particle dynamics.

  11. Aeolian processes aboard a Space Station: Saltation and particle trajectory analysis

    NASA Technical Reports Server (NTRS)

    White, Bruce R.; Greeley, Ronald; Iversen, James D.; Leach, R. N.

    1987-01-01

    The Carousel Wind Tunnel (CWT) proposed to study aeolian processes aboard a Space Station consists of two concentric rotating drums. The space between the two drums comprises the wind tunnel section. Differential rates of rotation of the two drums would provide a wind velocity with respect to either drum surface. Preliminary results of measured velocity profiles made in a CWT prototype indicate that the wall bounded boundary layer profiles are suitable to simuate flat plate turbulent boundary layer flow. The two dimensional flate plate Cartesian coordinate equations of motion of a particle moving through the air are explained. In order to assess the suitability of CWT in the analysis of the trajectories of windblown particles, a series of calculations were conducted comparing cases for gravity with those of zero gravity. Results from the calculations demonstrate that a wind tunnel of the carousel design could be fabricated to operate in a space station environment and that experiments could be conducted which would yield significant results contributing to the understanding of the physics of particle dynamics.

  12. Wingnut (Juglandaceae) as a new generic host for Pityophthorus juglandis (Coleoptera: Curculionidae) and the thousand cankers disease pathogen, Geosmithia morbida (Ascomycota: Hypocreales)

    Treesearch

    Stacy M. Hishinuma; Paul L. Dallara; Mohammad A. Yaghmour; Marcelo M. Zerillo; Corwin M. Parker; Tatiana V. Roubtsova; Tivonne L. Nguyen; Ned A. Tisserat; Richard M. Bostock; Mary L. Flint; Steven J. Seybold

    2016-01-01

    The walnut twig beetle (WTB), Pityophthorus juglandis Blackman (Coleoptera: Curculionidae), vectors a fungus, Geosmithia morbida Kolarík, Freeland, Utley, and Tisserat (Ascomycota: Hypocreales), which colonises and kills the phloem of walnut and butternut trees, Juglans Linnaeus (Juglandaceae). Over the...

  13. A new species of Niditinea (Tineidae: Tineinae) with a preference for bird nests and the known larval habitats of the species in the United States

    USDA-ARS?s Scientific Manuscript database

    We describe and illustrate Niditinea sabroskyi new species, a species mostly associated with bird nests. We provide diagnostic information to distinguish the new species from the other two species occurring in the United States, Niditinea fuscella (Linnaeus, 1758) and Niditinea orleansella (Chambers...

  14. Gardens of paradise.

    PubMed

    Müller-Wille, S

    2001-06-01

    Two hundred and fifty years ago, the Swedish naturalist Carolus Linnaeus (1707-1778) published his Philosophia botanica. This textbook in botanical science was widely read well into the 19th century. Today it is remembered mainly for two things: the introduction of binomial nomenclature and the formulation of a fixist and creationist species concept. While the former achievement is seen as a practical tool, still applicable for purposes of identification and information retrieval, the latter is usually deemed to have been one of the main obstacles to scientific progress in biology. That both achievements were not independent of each other, but interlocked theoretically and grounded in a specific scientific practice still thriving today--the collection of plant specimens in botanical gardens--is usually overlooked. The following article tries to uncover these connections and to demonstrate the significance that Linnaeus' achievements had for modern biology.

  15. Bute's "Botanical tables": dictated by nature.

    PubMed

    Lazarus, Maureen H; Pardoe, Heather S

    2009-10-01

    In the final years of his life, after a long and turbulent political career, John Stuart, third Earl of Bute, was at last free to indulge in one of his passions: botany. The publication of Linnaeus's "Systema naturae" in 1735 threw the botanical world into disarray and academic argument raged throughout Europe. The production of the "Botanical tables" (1785) was an ambitious project to explain Bute's individual view of Linnaeus's system of taxonomy and was particularly composed for the "Fair Sex". Twelve volumes were published privately and presented to family, royalty and botanical colleagues across Europe. The "Botanical tables" were illustrated by the renowned botanical artist, John Miller. The illustrations are both aesthetically pleasing and scientifically correct. In this paper we consider the circumstances of the production of the "Botanical tables" and explore how the original sets of this publication and original material have been dispersed.

  16. Comparative cytogenetics of some marsupial species (Didelphimorphia, Didelphidae) from the Amazon basin

    PubMed Central

    Silva, Carlos Eduardo Faresin e; de Andrade, Rodrigo Amaral; de Souza, Érica Martinha Silva; Eler, Eduardo Schmidt; da Silva, Maria Nazareth Ferreira; Feldberg, Eliana

    2017-01-01

    Abstract We investigated the karyotype of 18 didelphid species captured at 13 localities in the Brazilian Amazon, after conventional staining, C-banding, Ag-NOR and fluorescent in situ hybridization (FISH) using the 18S rDNA probe. Variations were found in the X chromosome, heterochromatin distribution and the 18S rDNA sequence. The main variation observed was in the position of the centromere in the X chromosome of Caluromys philander Linnaeus, 1758 and Marmosa murina Linnaeus, 1758. For both species, the X chromosome showed a geographical segregation in the pattern of variation between eastern and western Brazil, with a possible contact area in the central Amazon. C-banding on the X chromosome revealed two patterns for the species of Marmosops Matschie, 1916, apparently without geographic or specific relationships. The nucleolus organizer region (NOR) of all species was confirmed with the 18S rDNA probe, except on the Y chromosome of Monodelphis touan Shaw, 1800. The distribution of this marker varied only in the genus Marmosa Gray, 1821 [M. murina Thomas, 1905 and M. demerarae Thomas, 1905]. Considering that simple NORs are seen as a plesiomorphic character, we conclude that the species Marmosa spp. and Didelphis marsupialis Linnaeus, 1758 evolved independently to the multiple condition. By increasing the sample, using chromosomal banding, and FISH, we verified that marsupials present intra- and interspecific chromosomal variations, which suggests the occurrence of frequent chromosomal rearrangements in the evolution of this group. This observation contrasts with the chromosomal conservatism expected for didelphids. PMID:29114362

  17. Bioinformatical and in vitro approaches to essential oil-induced matrix metalloproteinase inhibition.

    PubMed

    Zeidán-Chuliá, Fares; Rybarczyk-Filho, José L; Gursoy, Mervi; Könönen, Eija; Uitto, Veli-Jukka; Gursoy, Orhan V; Cakmakci, Lutfu; Moreira, José C F; Gursoy, Ulvi K

    2012-06-01

    Essential oils carry diverse antimicrobial and anti-enzymatic properties. Matrix metalloproteinase (MMP) inhibition characteristics of Salvia fruticosa Miller (Labiatae), Myrtus communis Linnaeus (Myrtaceae), Juniperus communis Linnaeus (Cupressaceae), and Lavandula stoechas Linnaeus (Labiatae) essential oils were evaluated. Chemical compositions of the essential oils were analyzed by gas chromatography-mass spectrometry (GC-MS). Bioinformatical database analysis was performed by STRING 9.0 and STITCH 2.0 databases, and ViaComplex software. Antibacterial activity of essential oils against periodontopathogens was tested by the disc diffusion assay and the agar dilution method. Cellular proliferation and cytotoxicity were determined by commercial kits. MMP-2 and MMP-9 activities were measured by zymography. Bioinformatical database analyses, under a score of 0.4 (medium) and a prior correction of 0.0, gave rise to a model of protein (MMPs and tissue inhibitors of metalloproteinases) vs. chemical (essential oil components) interaction network; where MMPs and essential oil components interconnected through interaction with hydroxyl radicals, molecular oxygen, and hydrogen peroxide. Components from L. stoechas potentially displayed a higher grade of interaction with MMP-2 and -9. Although antibacterial and growth inhibitory effects of essential oils on the tested periodontopathogens were limited, all of them inhibited MMP-2 in vitro at concentrations of 1 and 5 µL/mL. Moreover, same concentrations of M. communis and L. stoechas also inhibited MMP-9. MMP-inhibiting concentrations of essential oils were not cytotoxic against keratinocytes. We propose essential oils of being useful therapeutic agents as MMP inhibitors through a mechanism possibly based on their antioxidant potential.

  18. Linnaean sources and concepts of orchids

    PubMed Central

    Jarvis, Charlie; Cribb, Phillip

    2009-01-01

    Background Linnaeus developed a robust system for naming plants and a useful, if mechanical, system for classifying them. His binomial nomenclature proved the catalyst for the rapid development of our knowledge of orchids, with his work on the family dating back to 1737 in the first edition of his Genera Plantarum. His first work devoted to orchids, indeed the first monograph of the family, was published in 1740 and formed the basis for his account in Species Plantarum, published in 1753, in which he gave a binomial name to each species. Given the overwhelming number of orchids, he included surprisingly few – only 62 mostly European species – in Species Plantarum, his seminal work on the plants of the world. This reflects the European origin of modern botany and the concentration of extra-European exploration on other matters, such as conquest, gold and useful plants. Nevertheless, the scope of Linnaeus' work is broad, including plants from as far afield as India, Japan, China and the Philippines to the east, and eastern Canada, the West Indies and northern South America to the west. In his later publications he described and named a further 45 orchids, mostly from Europe, South Africa and the tropical Americas. Scope The philosophical basis of Linnaeus' work on orchids is discussed and his contribution to our knowledge of the family assessed. His generic and species concepts are considered in the light of current systematic ideas, but his adoption of binomial nomenclature for all plants is his lasting legacy. PMID:19182221

  19. The Enigmatic Longevity of Granular Materials on Mars: The Case for Geologically Episodic Dune Formation

    NASA Technical Reports Server (NTRS)

    Marshall, J.

    1999-01-01

    considerations of material strength versus mechanical work applied to the material, comminution to sub-sand size would be inevitable. Another semi-analytical approach might be taken by considering that the archetypal aeolian sand surface texture is an irregularly pitted ("frosted") surface composed of chipping hollows approximately 10 microns in diameter, 5 microns deep. Their volume = about 250 cubic microns, or about 1/25000 of the volume of a 100 micron diameter dune grain. Because a saltating grain always strikes another grain, then two surfaces are impacted. Thus each grain undergoes two impacts for every one saltation leap, when the impact statistics are considered for a closed dune system (it can be calculated that a grain can never undergo <1 impact, and never >2 per saltation leap). Hence, if we conservatively assume that there is damage to a grain each time it bounces, but with the minimum damage of only 2 microscopic craters per impact, then approximately 12,500 impacts are required to completely eliminate the grain. Of course, it would require only a fraction of this amount to reduce the grain to below sand size. A grain will make only several tens of saltation leaps on the stoss side of a dune before becoming buried on the lee slope. The dune then has to move its full length before the grain is exhumed again for abrasion. Even with this hiatus in transport, it is easy to see that terrestrial dunes need resupplying with sand in order to survive. In recent theoretical work it has been shown that martian aeolian transport may be initiated with high-speed grains, but this converts to a lower energy dynamic transport equilibrium in which a reptation population dominates grain transport (on Earth, at least half of the flux is by reptation and creep). On Mars, therefore, average grain speeds may be lower than those on Earth, or at least comparable. This would permit greater longevity for martian sands, but it would not go far enough to solve the survival problem. It may

  20. Response of reproductive traits and longevity of beet webworm to temperature, and implications for migration

    USDA-ARS?s Scientific Manuscript database

    Beet webworm, Loxostege sticticalis (Linnaeus) (Lepidoptera: Pyralidae), is a facultative long-distance migratory insect pest of crops in many regions between latitudes 36-55°N. Reproductive performance of L. sticticalis is very sensitive to thermal conditions, such that outbreaks of larvae are clos...

  1. American vascular plants published in Loefling’s Iter Hispanicum (1758) and its German translation(1766)

    USDA-ARS?s Scientific Manuscript database

    Loefling’s Iter Hispanicum (1758) and its subsequent translations, editions, issues, and facsimiles are analyzed for their impact on the nomenclature of American vascular plants. The book, edited by Linnaeus and posthumously published, contains descriptions of plants found in Venezuela (as well as i...

  2. Rocky Mountain Arsenal, Offpost Contamination Assessment, Technical Plan A003 (Revision A).

    DTIC Science & Technology

    1985-08-16

    Home Range Relationships of the Box Turtle , Terrapene c. carolina (Linnaeus). Ecol. Monogr. 20(4):351-378. Thorne, D.S. 1979. Biological Monitoring of...is maintained on the minicomputer. Monthly, the analyst will dismantle, clean, and rdassemble the torch and nebulizer to prevent serious sensitivity

  3. Rocky Mountain Arsenal Offpost Contamination Assessment. Technical Plan A003.

    DTIC Science & Technology

    1984-11-09

    Stickel, L.F. 1950. Populations and Home Range Relationships of the Box Turtle , Terrapene c. carolina (Linnaeus). Ecol. Monogr. 20(4):351-378. Thorne...maintained on the minicomputer. 3 Periodically, the analyst will dismantle, clean, and reassemble the torch and nebulizer to prevent serious sensitivity

  4. Evaluating bee (Hymenoptera: Apoidea) diversity using malaise traps in coffee landscapes of Costa Rica

    USDA-ARS?s Scientific Manuscript database

    Even though Arabica coffee (Coffea arabica Linnaeus, Rubiaceae) can self-pollinate, bees are important pollinators, without which there is lower fruit quality and yield. We studied bee diversity in coffee agroecosystems in Costa Rica during two coffee flowering seasons (2005 and 2006). Malaise traps...

  5. Characterization of Tolypocladium cylindrosporum (Hypocreales: Ophiocordycipitacea) and its impact against Aedes aegypti and Aedes albopictus eggs at low temperature

    USDA-ARS?s Scientific Manuscript database

    We examined the growth characteristics of Tolypocladium cylindrosporum IBT 41712 and its potential to infect eggs of Aedes aegypti Linnaeus and Aedes albopictus (Skuse) mosquitoes at low temperature (15 deg C). When grown on sabouraud dextrose agar supplemented with yeast extract, IBT 41712 formed w...

  6. Medical Surveillance Monthly Report (MSMR). Volume 19, Number 9, September 2012

    DTIC Science & Technology

    2012-09-01

    fever, headache, muscle aches, rash, abdominal pain, nau- sea, vomiting, and diarrhea . In severe cases, WNV infections can cause brain in# amma...Linnaeus, the northern house mosquito, are distributed across the United States and can transmit WNV, St. Louis encephalitis and dog heartworm (Figures

  7. Community composition and structure had no effect on forest susceptibility to invasion by the emerald ash borer (Coleoptera: Buprestidae)

    Treesearch

    Annemarie Smith; Daniel A. Herms; Robert P. Long; Kamal J.K. Gandhi

    2015-01-01

    Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a non-native, wood-boring beetle that has caused widespread mortality of ash (Fraxinus Linnaeus (Oleaceae)) in eastern North America. During 2004-2007, we determined whether forest community composition and structure of black (F. nigra...

  8. Sand transportation and reverse patterns over leeward face of sand dune

    NASA Astrophysics Data System (ADS)

    Jiang, Hong; Dun, Hongchao; Tong, Ding; Huang, Ning

    2017-04-01

    Sand saltation has complex interactions with turbulent flow and dune form. Most models of wind-blown sand consider ideal circumstances such as steady wind velocity and a flat surface, and the bulk of data on wind flow and sand transport over an individual dune has focused mostly on the influence of dune shape or inter-dune space on the wind flow, neglecting the effect of morphology on sand saltation, particularly airflow and sand transportation over the leeward slope. Wind flow structures over the leeward slope of sand dunes have a fundamental influence on the organization of sand dunes. In order to understand sand dune dynamics, lee face airflow and sediment transportation should be paid more attention. Previous field observations could not measure turbulent flow structure well because of the limited observation points and the influence of experiment structure on wind field. In addition, the reverse sand particles over leeward face could not be collected by sand trap in field. Numerous field observations could not measure turbulent flow structure because of the limited observation points and the influence of experimental structures on the wind field. In addition, the reverse transport of sand particles over leeward face could not be collected by sand traps in field. Therefore, this paper aims to investigate the turbulent flow structure and sand transport pattern over the leeward slope. A numerical model of sand saltation over slope terrain is constructed, which also considers the coupling effects between air flow and sand particles. The large eddy simulation method is used to model turbulent flow. Sand transport is simulated by tracking the trajectory of each sand particle. The results show that terrain significantly alters the turbulent air flow structure and wind-blown sand movement, especially over the leeward slope. Here, mass flux increases initially and then decreases with height in the reversed flow region in the direction of wind flow, and the mass flux

  9. Dust devil characteristics and associated dust entrainment based on large-eddy simulations

    NASA Astrophysics Data System (ADS)

    Klose, Martina; Kwidzinski, Nick; Shao, Yaping

    2015-04-01

    The characteristics of dust devils, such as occurrence frequency, lifetime, size, and intensity, are usually inferred from in situ field measurements and remote sensing. Numerical models, e.g. large-eddy simulation (LES) models, have also been established as a tool to investigate dust devils and their structures. However, most LES models do not contain a dust module. Here, we present results from simulations using the WRF-LES model coupled to the convective turbulent dust emission (CTDE) scheme of Klose et al. (2014). The scheme describes the stochastic process of aerodynamic dust entrainment in the absence of saltation. It therefore allows for dust emission even below the threshold friction velocity for saltation. Numerical experiments have been conducted for different atmospheric stability and background wind conditions at 10 m horizontal resolution. A dust devil tracking algorithm is used to identify dust devils in the simulation results. The detected dust devils are statistically analyzed with regard to e.g. radius, pressure drop, lifetime, and turbulent wind speeds. An additional simulation with higher horizontal resolution (2 m) is conducted for conditions, which are especially favorable for dust devil development, i.e. unstable atmospheric stratification and weak mean winds. The higher resolution enables the identification of smaller dust devils and a more detailed structure analysis. Dust emission fluxes, dust concentrations, and dust mass budgets are calculated from the simulations. The results are compared to field observations reported in literature.

  10. Grain size statistics and depositional pattern of the Ecca Group sandstones, Karoo Supergroup in the Eastern Cape Province, South Africa

    NASA Astrophysics Data System (ADS)

    Baiyegunhi, Christopher; Liu, Kuiwu; Gwavava, Oswald

    2017-11-01

    Grain size analysis is a vital sedimentological tool used to unravel the hydrodynamic conditions, mode of transportation and deposition of detrital sediments. In this study, detailed grain-size analysis was carried out on thirty-five sandstone samples from the Ecca Group in the Eastern Cape Province of South Africa. Grain-size statistical parameters, bivariate analysis, linear discriminate functions, Passega diagrams and log-probability curves were used to reveal the depositional processes, sedimentation mechanisms, hydrodynamic energy conditions and to discriminate different depositional environments. The grain-size parameters show that most of the sandstones are very fine to fine grained, moderately well sorted, mostly near-symmetrical and mesokurtic in nature. The abundance of very fine to fine grained sandstones indicate the dominance of low energy environment. The bivariate plots show that the samples are mostly grouped, except for the Prince Albert samples that show scattered trend, which is due to the either mixture of two modes in equal proportion in bimodal sediments or good sorting in unimodal sediments. The linear discriminant function analysis is dominantly indicative of turbidity current deposits under shallow marine environments for samples from the Prince Albert, Collingham and Ripon Formations, while those samples from the Fort Brown Formation are lacustrine or deltaic deposits. The C-M plots indicated that the sediments were deposited mainly by suspension and saltation, and graded suspension. Visher diagrams show that saltation is the major process of transportation, followed by suspension.

  11. Temporal and spatial variability of aeolian sand transport: Implications for field measurements

    NASA Astrophysics Data System (ADS)

    Ellis, Jean T.; Sherman, Douglas J.; Farrell, Eugene J.; Li, Bailiang

    2012-01-01

    Horizontal variability is often cited as one source of disparity between observed and predicted rates of aeolian mass flux, but few studies have quantified the magnitude of this variability. Two field projects were conducted to evaluate meter-scale spatial and temporal in the saltation field. In Shoalhaven Heads, NSW, Australia a horizontal array of passive-style sand traps were deployed on a beach for 600 or 1200 s across a horizontal span of 0.80 m. In Jericoacoara, Brazil, traps spanning 4 m were deployed for 180 and 240 s. Five saltation sensors (miniphones) spaced 1 m apart were also deployed at Jericoacoara. Spatial variation in aeolian transport rates over small spatial and short temporal scales was substantial. The measured transport rates ( Q) obtained from the passive traps ranged from 0.70 to 32.63 g/m/s. When considering all traps, the coefficient of variation ( CoV) values ranged from 16.6% to 67.8%, and minimum and maximum range of variation coefficient ( RVC) values were 106.1% to 152.5% and 75.1% to 90.8%, respectively. The miniphone Q and CoV averaged 47.1% and 4.1% for the 1260 s data series, which was subsequently sub-sampled at 60-630 s intervals to simulate shorter deployment times. A statistically significant ( p < 0.002), inverselinear relationship was found between sample duration and CoV and between Q and CoV, the latter relationship also considering data from previous studies.

  12. Rocky Mountain Arsenal Offpost Contamination Assessment Technical Plan A003.

    DTIC Science & Technology

    1984-11-09

    Relationships of the Box3 Turtle , Terrapene c. carolina (Linnaeus). Ecol. Monogr. 20(4):351-378. Thorne, D.S. 1979. Biological Monitoring of Pesticides, Heavy...analyst will dismantle, clean, and reassemble the torch and nebulizer to prevent serious sensitivity problems. Calibration with selected standards will be

  13. Natural enemies of emerald ash borer (Coleoptera: Buprestidae) in northeast China, with notes on two species of parasitic Coleoptera

    Treesearch

    Xiao-Yi Wang; Liang-Ming Cao; Zhong-Qi Yang; Jian J. Duan; Juli R. Gould; Leah S. Bauer

    2016-01-01

    To investigate natural enemies of emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), in northeastern China, we conducted field surveys of ash (Fraxinus Linnaeus (Oleaceae)) trees in semi-natural forests and plantations at variable EAB densities from 2008 to 2013. Our surveys revealed a complex of...

  14. Allantoinase in lake trout (Salvelinus namaycush): In vitro effects of PCBs, DDT and metals

    USGS Publications Warehouse

    Passino, Dora R. May; Cotant, Carol A.

    1979-01-01

    1. Allantoinase, an enzyme in the purine-urea cycle, was found in livers of Salvelinus namaycush (Osteichthyes: Salmoniformes).2. The enzyme was active from pH 6.6 to 8.2 at 37°C and from pH 7.4 to 9.0 at 10°C and had an Arrhenius energy was activation of 11.0 kcal/mol and a temperature quotient of 2.0. The Km of the enzyme homogenate was 8.4 mM allantoin.3. The concentrations of inorganic metals at which 50% inhibition occurred during in vitro exposure were 6.0 mg/l Cu2+, 6.7 mg/l Cd2+, 34 mg/l Hg2+ and 52 mg/l Pb2+. The in vitro sensitivity to PCBs, DDT and DDE and kinetics in the presence of metals were determined.4. Allantoinase activity was negatively correlated with body length for fish from Lake Michigan but not from Lake Superior or the laboratory.

  15. Does iron inhibit cryptoendolithic microbial communities?

    NASA Technical Reports Server (NTRS)

    Johnston, C. G.; Vestal, J. R.; Friedmann, E. I. (Principal Investigator)

    1988-01-01

    Photosynthetic activity of three cryptoendolithic microbial communities was studied under controlled conditions in the laboratory. In two of these communities, the dominant organisms were lichens, collected from Linnaeus Terrace and from Battleship Promontory. The third community, dominated by cyanobacteria, was collected from Battleship Promontory. Both sites are in the ice-free valleys of southern Victoria Land. Previous efforts have shown how physical conditions can influence metabolic activity in endolithic communities (Kappen and Friedmann 1983; Kappen, Friedmann, and Garty 1981; Vestal, Federle, and Friedmann 1984). Biological activity can also be strongly influenced by the chemical environment. Inorganic nutrients such as nitrate, ammonia, and phosphate are often limiting factors, so their effects on photosynthetic carbon-14 bicarbonate incorporation were investigated. Iron and manganese are two metals present in Linnaeus Terrace and Battleship Promontory sandstones, and their effects on photosynthesis were also studied. The results may add to our understanding of biogeochemical interactions within this unique microbial community.

  16. Conflict resolution of grammar and gender for avian species-group names under Article 31.2.2 of the ICZN Code: is gender agreement worth it?

    PubMed

    Schodde, Richard; Bock, Walter

    2016-06-22

    We analyze recent nomenclatural treatment of selected avian species-group names that may be either adjective and variable or noun and invariable. In 27 such names, we found that 14 previously identified as adjectives are nouns under Article 31.2.2 of the International Code of Zoological Nomenclature. Five of them may require correction in current checklists; they are bresilius in Ramphocelus bresilius (Linnaeus, 1766) to bresilia, germana in Amblyornis macgregoriae germana Rothschild, 1910 to germanus, argentinus in Muscisaxicola cinereus argentinus Hellmayr, 1932 to argentina, martinicus in Porphyrio martinicus (Linnaeus, 1766) to martinica, and moluccus in Threskiornis moluccus (Cuvier, 1829) to molucca. Mindful of the compounding effect of species-genus recombination from taxonomic revision, we reach the conclusion, not new, that the requirement for gender agreement in species-group names is the single biggest cause of nomenclatural instability in zoology. To resolve it, we support replacing gender agreement by original spellings for species-group names.

  17. Nematodes parasitizing Trachurus trachurus (L.) and Boops boops (L.) from Algeria.

    PubMed

    Ichalal, Keltoum; Ramdane, Zouhir; Ider, Djamila; Kacher, Mohammed; Iguerouada, Mokrane; Trilles, Jean-Paul; Courcot, Luci; Amara, Rachid

    2015-11-01

    A total of 455 Boops boops (Linnaeus, 1758) and 953 Trachurus trachurus Linnaeus, 1758 from the east coast of Algeria were examined for their parasitic Nematoda. Two hundred ninety-five specimens of larval stages L3 and L4 were collected from the peritoneal cavity of these two examined fishes. Photonic and scanning electronic microscopy (SEM) studies were performed on these larvae specimens in order to characterize their morphology. Two different species of Nematoda (Anisikidae) were identified: Anisakis simplex (Rudolphi, 1809) and Hysterothylacium aduncum (Rudolphi, 1802). These two parasitic species were reported for the first time on T. trachurus and B. boops from the eastern coast of Algeria. These parasites were attached on different organs in the abdominal cavity (particularly on ovaries and testes). The infestation rate changed according to the month and the host size. The parasitism did not show a significant negative impact on the condition of the examined fishes.

  18. Behavior of Windblown Sand on Mars: Results from Single-Particle Experiments

    NASA Technical Reports Server (NTRS)

    Marshall, J. R.; Borucki, J.; Sagan, C.

    1999-01-01

    Experiments are investigating the behavior of individual sand grains in the high-energy martian aeolian regime. Energy partitioning during impact of a saltating grain determines grain longevity, but it also influences the way in which the bed becomes mobilized by reptation. When single grains of sand are fired into loose beds, the bed can absorb up to 90% of the impact energy by momentum transfer to other grains; it has been discovered that the impacting grains cause circular craters even at low impact angles. Hundreds of grains can be splashed by a single high-velocity (100 m/s) impact causing more bed disturbance through reptation than previously thought. The research is supported by NASA's PG&G Program. Because the martian aeolian environment in both high energy and of long duration, the most mobile fractions of windblown sand should have eradicated themselves by attrition, unless sand supply has kept pace with destruction. It is therefore important to understand the rate of grain attrition in order to make sense of the existence of vast dune fields on Mars. Attrition, has been addressed in other studies, but precise data for a single saltating grain striking a loose bed of sand have not been acquired -- the quintessential case to be understood for dunes on Mars. To acquire these data, we are employing a compound crossbow which has the bolt-firing mechanism replaced with a pneumatically-automated sabot system. The sabot can launch individual grains of sand of any size between several millimeters and about 50 microns, at velocities up to 100m/s. This is around the maximum velocity expected for saltating grains on Mars. The sabot sled is equipped with photoelectric sensors for measuring shot velocity. Baffling of the grain's exit orifice has enabled projection of single grains without significant aerodynamic effects from the sabot. Grains are fired into loose beds of sand at about 15 degrees from the horizontal (typical saltation trajectory at impact) while being

  19. Behavior of Windblown Sand on Mars: Results from Single-Particle Experiments

    NASA Astrophysics Data System (ADS)

    Marshall, J. R.; Borucki, J.; Sagan, C.

    1999-09-01

    Experiments are investigating the behavior of individual sand grains in the high-energy martian aeolian regime. Energy partitioning during impact of a saltating grain determines grain longevity, but it also influences the way in which the bed becomes mobilized by reptation. When single grains of sand are fired into loose beds, the bed can absorb up to 90% of the impact energy by momentum transfer to other grains; it has been discovered that the impacting grains cause circular craters even at low impact angles. Hundreds of grains can be splashed by a single high-velocity (100 m/s) impact causing more bed disturbance through reptation than previously thought. The research is supported by NASA's PG&G Program. Because the martian aeolian environment in both high energy and of long duration, the most mobile fractions of windblown sand should have eradicated themselves by attrition, unless sand supply has kept pace with destruction. It is therefore important to understand the rate of grain attrition in order to make sense of the existence of vast dune fields on Mars. Attrition, has been addressed in other studies, but precise data for a single saltating grain striking a loose bed of sand have not been acquired -- the quintessential case to be understood for dunes on Mars. To acquire these data, we are employing a compound crossbow which has the bolt-firing mechanism replaced with a pneumatically-automated sabot system. The sabot can launch individual grains of sand of any size between several millimeters and about 50 microns, at velocities up to 100m/s. This is around the maximum velocity expected for saltating grains on Mars. The sabot sled is equipped with photoelectric sensors for measuring shot velocity. Baffling of the grain's exit orifice has enabled projection of single grains without significant aerodynamic effects from the sabot. Grains are fired into loose beds of sand at about 15 degrees from the horizontal (typical saltation trajectory at impact) while being

  20. Progress in the classical biological control of Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) in North America

    Treesearch

    Leah S. Bauer; Jian J. Duan; Juli R. Gould; Roy. Van Driesche

    2015-01-01

    First detected in North America in 2002, the emerald ash borer (EAB) (Agrilus planipennis Fairmaire; Coleoptera: Buprestidae), an invasive phloem-feeding beetle from Asia, has killed tens of millions of ash (Fraxinus Linnaeus; Oleaceae) trees. Although few parasitoids attack EAB in North America, three parasitoid species were found...

  1. Impact of Tolypocladium cylindrosporum (Hypocreales: Ophiocordycipitaceae) on eggs of Aedes aegypti and Aedes albopictus at low temperature

    USDA-ARS?s Scientific Manuscript database

    We examined the potential of Tolypocladium cylindrosporum IBT 41712 to infect eggs of Aedes aegypti Linnaeus and Aedes albopictus (Skuse) mosquitoes at low temperature (15 deg C). To determine the optimum temperature for the fungus, we cultured the fungus at eight temperatures (4, 12, 15, 21, 28, 33...

  2. New records of Caligidae (Copepoda, Siphonostomatoida) from the Philippines.

    PubMed

    Maran, Balu Alagar Venmathi; Cruz-Lacierda, Erlinda R; Ohtsuka, Susumu; Nagasawa, Kazuya

    2016-10-11

    Parasitic copepods, especially sea lice (Caligidae) are causing economic problems in both aquaculture and to wild fishes around the world, but their study in at least some of the southeastern Asian countries, is still scanty. Here we provide new information on the distribution of 11 known species of parasitic copepods collected from 11 marine fish hosts from Iloilo, central part of the Philippines. Two species of the genus Anuretes Heller, 1865 and nine species of the genus Caligus Müller, 1785 were found to infest these hosts, i.e. Anuretes branchialis Rangnekar, 1953 from Platax orbicularis (Forsskål, 1775); A. plectorhynchi Yamaguti, 1936 from P. orbicularis and Plectorhinchus pictus (Tortonese, 1936); Caligus absens Ho, Lin et Chen, 2000 from Priacanthus macracanthus Cuvier in Cuvier & Valenciennes, 1829; C. asymmetricus Kabata, 1965 and C. coryphaenae (Steenstrup & Lütken, 1861) from Auxis thazard (Lacepède, 1800); C. bonito Wilson, 1905 from Coryphaena hippurus Linnaeus, 1758; C. cordyla Pillai, 1963 from Megalaspis cordyla (Linnaeus, 1758); C. cornutus Heegaard, 1962 from Sphyraena jello Cuvier in Cuvier & Valenciennes, 1829; C. epinepheli Yamaguti, 1936 from Scomberoides commersonnianus Lacepède, 1801; C. kanagurta Pillai, 1961 from Decapterus kurroides Bleeker, 1855, D. macarellus (Cuvier in Cuvier & Valenciennes, 1833) and C. hippurus; and C. rotundigenitalis Yü, 1933 from Scatophagus argus (Linnaeus, 1766). Attachment sites included the gill filaments and the body surface. Prevalence and mean intensity of caligids are provided in addition to an update on the checklist of caligids of the Philippines. Although reports on caligids in the Philippines are few, the published records indicate that sea lice are widely distributed throughout the archipelago.

  3. The Cultural Evolution of Democracy: Saltational Changes in A Political Regime Landscape

    PubMed Central

    Lindenfors, Patrik; Jansson, Fredrik; Sandberg, Mikael

    2011-01-01

    Transitions to democracy are most often considered the outcome of historical modernization processes. Socio-economic changes, such as increases in per capita GNP, education levels, urbanization and communication, have traditionally been found to be correlates or ‘requisites’ of democratic reform. However, transition times and the number of reform steps have not been studied comprehensively. Here we show that historically, transitions to democracy have mainly occurred through rapid leaps rather than slow and incremental transition steps, with a median time from autocracy to democracy of 2.4 years, and overnight in the reverse direction. Our results show that autocracy and democracy have acted as peaks in an evolutionary landscape of possible modes of institutional arrangements. Only scarcely have there been slow incremental transitions. We discuss our results in relation to the application of phylogenetic comparative methods in cultural evolution and point out that the evolving unit in this system is the institutional arrangement, not the individual country which is instead better regarded as the ‘host’ for the political system. PMID:22140565

  4. Atmospheric stability and diurnal patterns of aeolian saltation on the Llano Estacado

    USDA-ARS?s Scientific Manuscript database

    Aeolian transport is driven by aerodynamic surface stress imposed by turbulent winds in the Earth’s atmospheric boundary layer (ABL). ABL regime is influenced by stratification, which can either enhance or suppress production of turbulence by shear associated with the vertical gradient of streamwise...

  5. The cultural evolution of democracy: saltational changes in a political regime landscape.

    PubMed

    Lindenfors, Patrik; Jansson, Fredrik; Sandberg, Mikael

    2011-01-01

    Transitions to democracy are most often considered the outcome of historical modernization processes. Socio-economic changes, such as increases in per capita GNP, education levels, urbanization and communication, have traditionally been found to be correlates or 'requisites' of democratic reform. However, transition times and the number of reform steps have not been studied comprehensively. Here we show that historically, transitions to democracy have mainly occurred through rapid leaps rather than slow and incremental transition steps, with a median time from autocracy to democracy of 2.4 years, and overnight in the reverse direction. Our results show that autocracy and democracy have acted as peaks in an evolutionary landscape of possible modes of institutional arrangements. Only scarcely have there been slow incremental transitions. We discuss our results in relation to the application of phylogenetic comparative methods in cultural evolution and point out that the evolving unit in this system is the institutional arrangement, not the individual country which is instead better regarded as the 'host' for the political system.

  6. Warble? What’s a Warble? A recap of the human bot fly, Dermatobia hominis (L. Jr. 1781)

    USDA-ARS?s Scientific Manuscript database

    The human bot fly, Dermatobia hominis (Linnaeus Jr., 1781) is a major pest of livestock in Mexico, Central and South America. Myiasis caused by the larvae result in economic losses due to hide damage and reductions in weight gain and milk production. They have a broad host range which includes wildl...

  7. Hybrid weeds! Agent biotypes!: Montana's ever-evolving toadflax biological control soap opera

    Treesearch

    S. E. Sing; D. K. Weaver; S. M. Ward; J. Milan; C. L. Jorgensen; R. A. Progar; A. Gassmann; I. Tooevski

    2013-01-01

    An exotic toadflax stem mining weevil conventionally identified as Mecinus janthinus Germar has become widely established on Dalmatian toadflax [Linaria dalmatica (Linnaeus) Miller] in western North America, although agent density and control efficacy are highly variable across release sites (De Clerck-Floate & Miller, 2002; McClay & Hughes, 2007; Van Hezewijk...

  8. [Structure and ultrastructure of the ovary of Cichlasoma urophthalmus (Osteichthyes: Cichlidae)].

    PubMed

    Viedma, Rubí; Franco, Jonathan; Bedia, Carlos; Guedea Fernández, Guadalupe; Villa Zevallos, Héctor Barrera; Barrera Escorcia, Héctor

    2011-06-01

    The study of the normal development, differentiation, structure and function of various components of developing follicles in the ovaries of numerous fish species have been a consistent focus of comparative reproduction. The structural and ultrastructural features of gonads from Cichlasoma urophthalmus have received scarce attention. In this work, we realized a descriptive study of female gonads of Cichlasoma urophthalmus. A total of 40 samples were collected in the Veracruz Alvarado Lagoon, Mexico in 2007-2008 period including the windy, dry and rainy seasons. Female gonads were extracted and a portion was fixed in 4% formaldehyde for treatment for routine histology hematoxylin and eosin (HE) and another part was processed for transmission electron microscopy (TEM). The gonads were fixed in 3% glutaraldehyde and 2% osmium tetroxide, followed by dehydrated in ethanol 50%, 70%, 80%, 95% and 100% for inclusion in Epon, thin sections were then prepared and were contrasted with lead citrate and uranyl acetate. The process of oocyte development can be divided into five distinct stages (formation of oocytes from oogonia, primary growth, lipid stage, vitellogenesis and maturation). In this work, we found that the primary growth stage is characterized by intense RNA synthesis and the differentiation of the vitelline envelope. Secondary growth starts with the accumulation of lipid droplets in the oocyte cytoplasm (lipid stage), which is then followed by massive uptake and processing of proteins into yolk platelets (vitellogenic stage). During the maturation stage, the lipid inclusions coalesce into a single oil droplet, and hydrolysis of the yolk platelets leads to the formation of a homogeneous mass of fluid yolk in mature eggs. In conclusion, further studies should elucidate structure and ultrastructural changes in the ovarian follicular components, in C. urophthalmus during different stages of oocyte growth.

  9. Wind speed and sediment transport recovery in the lee of a vegetated and denuded nebkha within a nebkha dune field

    NASA Astrophysics Data System (ADS)

    Gillies, John A.; Nield, Joanna M.; Nickling, William G.

    2014-03-01

    Field observations of scaled wind speed and sand transport recovery in the lee of a nebka within a field of nebkhas and then subsequently for the nebkha denuded of its vegetation cover were collected. The measurements of wind speed at 0.4 times the element height indicate that for both conditions wind speed recovery in the lee is exponential. The porous vegetation cover influences the rate of this recovery being more gradual for the vegetated form. The return to equilibrium wind speed occurs in both cases at approximately eight element heights. For either case the recovery of shear stress and the return to a constant value occurs much closer to the bluff body form than has been described for porous fences. The recovery of sand transport in the lee appears to be more rapid for the un-vegetated condition, which corresponds to the observed faster rate of wind speed increase. The observations did not show a continual increase in saltation flux with increasing downwind distance due to the increasing shear stress downwind and the increase that may be expected due to the fetch effect. The change in saltation flux with downwind distance was controlled by the sediment supply, which diminished with downwind distance. The interaction of a changing shear stress and the zone of influence created by the wind as it interacts with the roughness dimensions, along with the distribution of sediment available for transport bring increased complexity to modeling sand flux for this type of environment over different temporal scales.

  10. Aeolian transport in the field: A comparison of the effects of different surface treatments

    NASA Astrophysics Data System (ADS)

    Dong, Zhibao; Lv, Ping; Zhang, Zhengcai; Qian, Guangqiang; Luo, Wanyin

    2012-05-01

    Aeolian transport represents the result of wind-surface interactions, and therefore depends strongly on variations in the characteristics of the sediment surface. We conducted field observations of aeolian transport of typical dune sand in three 80 m × 80 m plots with different surface treatments: gravel-covered sand, enclosed shifting sand, and open (unprotected) shifting sand. The study was performed at the Shapotou Aeolian Experiment Site in the southeastern part of China's Tengger Desert to compare the effects of these different surface treatments on aeolian transport. To do so, we analyzed the flux density profiles and transport rates above each surface. The flux density profiles for all three treatments followed the exponential decay law that was proposed by most previous researchers to describe the saltation flux density profiles. Coefficients of the exponential decay function were defined as a function of the surface and the wind velocity. The enclosed and open plots with shifting sand had similar flux density profiles, but the flux density above gravel-covered plots showed that transport decayed more slowly with increasing height, producing flux density profiles with a higher average saltation height. The transport rate above the three treatment plots tended to increase proportionally with the cube of the mean wind velocity and with the maximum wind velocity during the observation period, but was more strongly correlated with the square of drift potential. Transport rates above the plot with open shifting sand were greater than those above the plots with enclosed shifting sand and the gravel-covered plot.

  11. Aeolian nutrient fluxes following wildfire in sagebrush steppe: Implications for soil carbon storage

    USGS Publications Warehouse

    Hasselquist, N.J.; Germino, M.J.; Sankey, J.B.; Ingram, L.J.; Glenn, N.F.

    2011-01-01

    Pulses of aeolian transport following fire can profoundly affect the biogeochemical cycling of nutrients in semi-arid and arid ecosystems. Our objective was to determine horizontal nutrient fluxes occurring in the saltation zone during an episodic pulse of aeolian transport that occurred following a wildfire in a semi-arid sagebrush steppe ecosystem in southern Idaho, USA. We also examined how temporal trends in nutrient fluxes were affected by changes in particle sizes of eroded mass as well as nutrient concentrations associated with different particle size classes. In the burned area, total carbon (C) and nitrogen (N) fluxes were as high as 235 g C m????'1 d????'1 and 19 g N m????'1 d????'1 during the first few months following fire, whereas C and N fluxes were negligible in an adjacent unburned area throughout the study. Temporal variation in C and N fluxes following fire was largely attributable to the redistribution of saltation-sized particles. Total N and organic C concentrations in the soil surface were significantly lower in the burned relative to the unburned area one year after fire. Our results show how an episodic pulse of aeolian transport following fire can affect the spatial distribution of soil C and N, which, in turn, can have important implications for soil C storage. These findings demonstrate how an ecological disturbance can exacerbate a geomorphic process and highlight the need for further research to better understand the role aeolian transport plays in the biogeochemical cycling of C and N in recently burned landscapes. ?? Author(s) 2011. CC Attribution 3.0 License.

  12. Dunes as New Evidence of Recently Active Surface Processes on Pluto

    NASA Astrophysics Data System (ADS)

    Radebaugh, Jani; Telfer, Matthew; Parteli, Eric; Beyer, Ross A.; Bertrand, Tanguy; Forget, Francois; Nimmo, Francis; Grundy, William M.; Moore, Jeffrey M.; Stern, S. Alan; New Horizons Team

    2017-10-01

    The surface of Pluto contains hundreds of aligned, regularly spaced features best described as transverse dunes (Telfer et al. in review). They are spaced by 500-700 meters, are several tens of kilometers long, and are subparallel and with a slightly undulatory planform, as seen by the New Horizons LORRI instrument. Their crests are orthogonal to wind streaks seen nearby, and therefore to the assumed regional winds. They sit atop the nitrogen-rich informally named Sputnik Planitia continental glacier at the base of the informally named Al-Idrisi Montes and appear from New Horizons MVIC data to have a composition enriched in methane. Their presence requires there to be particles that can be saltated as well as wind. The particles, or “sands”, are likely composed of relatively hard methane ice, possibly derived from the methane snow seen to blanket the mountain summits. While Pluto’s nitrogen-rich atmosphere fluctuates in density, perhaps dramatically, current modelled conditions allow for winds that are required to saltate the ice sands (<~10 m/s). These features are relatively fresh in appearance, especially in comparison with features farther south that have severe sublimation erosion textures and deformation from glacier flow. Furthermore, they lie atop convection cell margins of Sputnik Planitia, which overturns at rates of ~500 ka. This indicates the dune-like landforms of Pluto are relatively young. This has implications for the surface activity of other large Kuiper Belt Objects and the interaction between limited solar heating and the exotic properties of their surfaces and atmospheres.

  13. Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

    NASA Astrophysics Data System (ADS)

    Tegen, I.; Heinold, B.; Todd, M.; Helmert, J.; Washington, R.; Dubovik, O.

    2006-05-01

    We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx) that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust production occurs via self-abrasion of saltating diatomite flakes in the Bodélé, the emission model based on the assumption of dust production by saltation and using observed surface wind speeds as input parameters reproduces observed dust optical thicknesses well. Although the peak wind speeds in the regional model underestimate the highest wind speeds occurring on 10-12 March 2005, the spatio-temporal evolution of the dust cloud can be reasonably well reproduced by this model. Dust aerosol interacts with solar and thermal radiation in the regional model; it is responsible for a decrease in maximum daytime temperatures by about 5 K at the beginning the dust storm on 10 March 2005. This direct radiative effect of dust aerosol accounts for about half of the measured temperature decrease compared to conditions on 8 March. Results from a global dust model suggest that the dust from the Bodélé is an important contributor to dust crossing the African Savannah region towards the Gulf of Guinea and the equatorial Atlantic, where it can contribute up to 40% to the dust optical thickness.

  14. Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

    NASA Astrophysics Data System (ADS)

    Tegen, I.; Heinold, B.; Todd, M.; Helmert, J.; Washington, R.; Dubovik, O.

    2006-09-01

    We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx) that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust production occurs via self-abrasion of saltating diatomite flakes in the Bodélé, the emission model based on the assumption of dust production by saltation and using observed surface wind speeds as input parameters reproduces observed dust optical thicknesses well. Although the peak wind speeds in the regional model underestimate the highest wind speeds occurring on 10-12 March 2005, the spatio-temporal evolution of the dust cloud can be reasonably well reproduced by this model. Dust aerosol interacts with solar and thermal radiation in the regional model; it is responsible for a decrease in maximum daytime temperatures by about 5 K at the beginning the dust storm on 10 March 2005. This direct radiative effect of dust aerosol accounts for about half of the measured temperature decrease compared to conditions on 8 March. Results from a global dust model suggest that the dust from the Bodélé is an important contributor to dust crossing the African Savannah region towards the Gulf of Guinea and the equatorial Atlantic, where it can contribute up to 40% to the dust optical thickness.

  15. Dark material in the polar layered deposits and dunes on Mars

    NASA Astrophysics Data System (ADS)

    Herkenhoff, Ken E.; Vasavada, Ashwin R.

    1999-07-01

    Viking infrared thermal mapping and bistatic radar data suggest that the bulk density of the north polar erg material is much lower than that of the average Martian surface or of dark dunes at lower latitudes. We have derived a thermal inertia of 245-280Jm-2s-1/2K-1(5.9-6.7×10-3calcm-2s-1/2K-1) for the Proctor dune field and 25-150Jm-2s-1/2K-1(0.6-3.6×10-3calcm-2s-1/2K-1) for the north polar erg. The uniqueness of the thermophysical properties of the north polar erg material may be due to a unique polar process that has created them. The visible and near-infrared spectral reflectance of the erg suggests that the dark material may be composed of basalt or ferrous clays. These data are consistent with the dark material being composed of basaltic ash or filamentary sublimate residue (FSR) particles derived from erosion of the layered deposits. Dark dust may be preferentially concentrated at the surface of the layered deposits by the formation of FSR particles upon sublimation of water ice. Further weathering and erosion of these areas of exposed layered deposits may form the dark, saltating material that is found in both polar regions. Dark FSR particles may saltate for great distances before eventually breaking down into dust grains, re-mixing with the global dust reservoir, and being recycled into the polar layered deposits via atmospheric suspension.

  16. Velocity of motion across the skin influences perception of tactile location

    PubMed Central

    Nguyen, Elizabeth H. L.; Taylor, Janet L.; Brooks, Jack

    2015-01-01

    We investigated the influence of motion context on tactile localization, using a paradigm similar to the cutaneous rabbit or sensory saltation (Geldard FA, Sherrick CE. Science 178: 178–179, 1972). In one of its forms, the rabbit stimulus consists of a tap in one location quickly followed by another tap elsewhere, creating the illusion that the two taps are near each other. Instead of taps, we used position of a halted brush and instead of distance judgment, localization responses. The brush moved across the skin of the left forearm, creating a clear motion signal before and after a rabbitlike leap of 10 cm (at 100 cm/s). Three before-and-after velocities (7.5, 15, or 30 cm/s) were used. Participants (n = 13) pointed with their right arm at the felt location of the brush when it halted either 1 cm before or after the leap. These stops were 12 cm apart, but distances computed from localization responses were only 5.4, 6.5, and 7.5 cm for the three velocities, respectively (F[2,11] = 15.19, P = 0.001). Thus the leap resulted in compressive position shift, as described previously for sensory saltation, but modulated by motion velocity before the leap: the slower the motion, the greater the shift opposite to motion direction. No gap in stimulation was perceived. We propose that velocity extrapolation causes the position shift: extrapolated motion does not have enough time to bridge the real spatial gap and thus assigns a closer location to the skin on the opposite side of the gap. PMID:26609112

  17. Dark material in the polar layered deposits and dunes on Mars

    USGS Publications Warehouse

    Herkenhoff, K. E.; Vasavada, A.R.

    1999-01-01

    Viking infrared thermal mapping and bistatic radar data suggest that the bulk density of the north polar erg material is much lower than that of the average Martian surface or of dark dunes at lower latitudes. We have derived a thermal inertia of 245-280 J m-2 s-1/2 K-1 (5.9-6.7 ?? 10-3 cal cm-2 s-1/2 K-1) for the Proctor dune field and 25-150 J m-2 s-1/2 K-1 (0.6-3.6 ?? 10-3 cal cm-2 s-1/2 K-1) for the north polar erg. The uniqueness of the thermophysical properties of the north polar erg material may be due to a unique polar process that has created them. The visible and near-infrared spectral reflectance of the erg suggests that the dark material may be composed of basalt or ferrous clays. These data are consistent with the dark material being composed of basaltic ash or filamentary sublimate residue (FSR) particles derived from erosion of the layered deposits. Dark dust may be preferentially concentrated at the surface of the layered deposits by the formation of FSR particles upon sublimation of water ice. Further weathering and erosion of these areas of exposed layered deposits may form the dark, saltating material that is found in both polar regions. Dark FSR particles may saltate for great distances before eventually breaking down into dust grains, re-mixing with the global dust reservoir, and being recycled into the polar layered deposits via atmospheric suspension. Copyright 1999 by the American Geophysical Union.

  18. Comment on "Minimal size of a barchan dune".

    PubMed

    Andreotti, B; Claudin, P

    2007-12-01

    It is now an accepted fact that the size at which dunes form from a flat sand bed as well as their "minimal size" scales on the flux saturation length. This length is by definition the relaxation length of the slowest mode toward equilibrium transport. The model presented by Parteli, Durán, and Herrmann [Phys. Rev. E 75, 011301 (2007)] predicts that the saturation length decreases to zero as the inverse of the wind shear stress far from the threshold. We first show that their model is not self-consistent: even under large wind, the relaxation rate is limited by grain inertia and thus cannot decrease to zero. A key argument presented by these authors comes from the discussion of the typical dune wavelength on Mars (650 m) on the basis of which they refute the scaling of the dune size with the drag length evidenced by Claudin and Andreotti [Earth Planet. Sci. Lett. 252, 30 (2006)]. They instead propose that Martian dunes, composed of large grains (500 microm), were formed in the past under very strong winds. We emphasize that this saltating grain size, estimated from thermal diffusion measurements, is far from straightforward. Moreover, the microscopic photographs taken by the rovers on Martian Aeolian bedforms show a grain size of 87+/-25 microm together with hematite spherules at millimeter scale. As those so-called "blueberries" cannot be entrained more frequently than a few hours per century, we conclude that the saltating grains on Mars are the small ones, which gives a second strong argument against the model of Parteli.

  19. Applying the Scientific Method & Phylogenetics to Understand the Transition from Kingdoms to Domains: Does One Plus One Equal Five, Six, or Three?

    ERIC Educational Resources Information Center

    Davis, Sandra L.

    2012-01-01

    The progression of the taxonomic organization of life from Linnaeus's original two kingdoms to the traditional five-kingdom system to today's widely accepted three-domain system is explored in a group-learning activity. Working with a set of organisms, students organize them into each system. Discussion after each step focuses on viewing…

  20. Alternate hosts of Blepharipa pratensis (Meigen)

    Treesearch

    Paul A. Godwin; Thomas M. Odell

    1977-01-01

    A current tactic for biological control of the gypsy moth, Lymantria dispar Linnaeus, is to release its parasites in forests susceptible to gypsy moth damage before the gypsy moth arrives. The basic assumption in these anticipatory releases is that the parasites can find and utilize native insects as hosts in the interim. Blepharipa...

  1. Sediment-transport (wind) experiments in zero-gravity

    NASA Technical Reports Server (NTRS)

    Iverson, J.; Gillette, D.; Greeley, R.; Lee, J.; Mackinnon, I.; Marshall, J.; Nickling, W.; Werner, B.; White, B.; Williams, S.

    1986-01-01

    The carousel wind tunnel (CWT) can be a significant tool for the determination of the nature and magnitude of interparticlar forces at threshold of motion. By altering particle and drum surface electrical properties and/or by applying electric potential difference across the inner and outer drums, it should be possible to separate electrostatic effects from other forces of cohesion. Besides particle trajectory and bedform analyses, suggestions for research include particle aggregation in zero and subgravity environments, effect of suspension-saltation ratio on soil abrasion, and the effects of shear and shearfree turbulence on particle aggregation as applied to evolution of solar nebula.

  2. Plant Collections Online: Using Digital Herbaria in Biology Teaching

    ERIC Educational Resources Information Center

    Flannery, Maura C.

    2013-01-01

    Herbaria are collections of preserved plants specimens, some of which date back to the 16th century. They are essential to botanical research, especially in systematics. They can also be important historical documents. The collections of Lewis and Clark, Carolus Linnaeus, and Charles Darwin, to name a few, are primary sources for the study of…

  3. The mites associated with Ips typographus in Sweden

    Treesearch

    John C. Moser; Hubertus H. Eidmann; Jan R. Regnander

    1989-01-01

    Twenty-four species of mites were found associated with Ips typographus (Linnaeus) collected from pherommone traps in Sweden, bringing to 38 the total recorded for this scolytid. Because three of the species are parasites, it may be possible to use them in biological control of I. typographus. Couplets from an earlier key to these...

  4. Wolf survival and population trend using non-invasive capture-recapture techniques in the Western Alps

    Treesearch

    Francesca Marucco; Daniel H. Pletscher; Luigi Boitani; Michael K. Schwartz; Kristy L. Pilgrim; Jean-Dominique Lebreton

    2009-01-01

    Population abundance and related parameters need to be assessed to implement effective wildlife management. These essential parameters are often very hard to obtain for rare, wide-ranging and elusive species, particularly those listed as endangered or threatened (IUCN 2001). In Italy, wolves Canis lupus Linnaeus 1758, now a fully protected species in Western Europe,...

  5. Case 3058. Arctocephalus F. Cuvier, 1826 and Callorhinus Gray, 1859 (Mammalia, Pinnipedia): proposed conservation by the designation of Phoca pusilla Schreber, [1775] as the type species of Arctocephalus; and Otaria Peron, 1816 and Eumetopias Gill, 1866: proposed conservation by the designation of Phoca leonina Molina, 1782 as the type species of Otaria

    USGS Publications Warehouse

    Gardner, A.L.; Robbins, C.B.

    1999-01-01

    The purpose of this application is to conserve the accustomed understanding and usage of the fur seal name Arctocephalus F. Cuvier, 1826 by the designation of Phoca pusilia Schreber, [1775] as the type species, thus conserving also the name Callorhinus Gray, 1859. At present Phoca ursina Linnaeus, 1758 is the valid type species of both Arctocephalus and Callorhinus. The name Arctocephalus relates to a genus of some seven fur seals from the southern hemisphere, while Callorhinus is used for the single species C. ursinus (Linnaeus) from the northern hemisphere. It is also proposed that the universal understanding of the names Otaria Peron, 1816 and Eumetopias Gill, 1866 should be conserved for the southern and northern sea lions respectively by designating Phoca leonina Molina, 1782 (for which the valid specific name is P. byronia de Blainville, 1820) as the type species of Otaria. At present Phoca jubata Schreber, [1776] is the type species of Otaria and the name Otaria is a senior subjective synonym of Eumetopias. The four genera Arctocephalus, Callorhinus, Otaria and Eumetopias are all placed in the family OTARIIDAE Gray, 1825.

  6. Morphology and identification of the mature larvae of several species of the genus Otiorhynchus (Coleoptera, Curculionidae, Entiminae) from Central Europe with an update of the life history traits.

    PubMed

    Gosik, Rafał; Sprick, Peter; Skuhrovec, Jiří; Deruś, Magdalena; Hommes, Martin

    2016-05-05

    The mature larvae of 14 Otiorhynchus taxa are described: O. (Otiorhynchus) armadillo (Rossi, 1792), O. (Nehrodistus) armatus Boheman, 1846, O. (Otiorhynchus) aurifer Boheman, 1843, O. (Pocodalemes) crataegi Germar, 1824, Otiorhynchus (Arammichnus) indefinitus Reitter, 1912 (syn. O. dieckmanni Magnano, 1979), O. (Choilisanus) raucus (Fa-bricius, 1777) and 3 taxa of the O. (Otiorhynchus) tenebricosus complex (Herbst, 1784), O. (Otiorhynchus) clavipes (Bonsdorff, 1785), O. (Otiorhynchus) fuscipes (Olivier, 1807) and O. (Otiorhynchus) lugdunensis Boheman, 1843, are described and illustrated for the first time. The larvae of (Otiorhynchus) meridionalis Gyllenhal, 1834, O. (Pendragon) ovatus (Linnaeus, 1758), O. (Zustalestus) rugosostriatus (Goeze, 1777), O. (Metopiorrhynchus) singularis (Linnaeus, 1767), and O. (Dorymerus) sulcatus (Fabricius, 1775) are redescribed and illustrated, and new characters are added. Important characters of the mature larvae (e.g. chaetotaxy, shape of head and body) are explained in detail and illustrated. A key to the identification of the mature larvae of 19 Otiorhynchus taxa is provided. Breeding and collecting data of the larvae are given, and the study is completed by a current overview on the life histories of all treated species.

  7. Pine Bluff Arsenal Fish Survey.

    DTIC Science & Technology

    2000-03-01

    6). Sites Collected: 39 Bowfins (Amiidae) Amia calva Linnaeus - Bowfin The bowfin is a primitive member of the monotypic family Amiidae, an...spotted gar (Lepisosteus oculatus), longnose gar (Lepisosteus osseus), bowfin ( Amia calva ), goldeye (Hiodon alosoides), goldfish (Carassius auratus...included the spotted gar (Lepisosteus oculatus),longnose gar (Lepisosteus osseus), bowfin ( Amia calva ), gizzard shad (Dorosoma cepedianum), threadfin

  8. Bugs' bugs

    Treesearch

    May R. Berenbaum; Thomas Eisner

    2008-01-01

    Although scientific progress leads to constant reevaluation and revision of concepts and ideas, one observation that has remained robust in the face of accumulating evidence across the centuries is that there are a lot of insects in the world. In 1758, in his profoundly influential book Systema Naturae, Carolus Linnaeus (1) described all animal species known at the...

  9. Lueheia inscripta (Westrumb, 1821) (Acanthocephala: Plagiorhynchidae) in anurans (Leptodactylidae: Bufonidae) from Mexico.

    PubMed

    Salgado-Maldonado, G; Caspeta-Mandujano, J M

    2010-06-01

    Juveniles of Lueheia inscripta (Westrumb, 1821 Travassos, 1919 (Acanthocephala: Plagiorhynchidae), an acanthocephalan with six lemnisci, are reported and described from mesenteries of frogs Leptodactylus fragilis Brochi, 1877 and a toad Bufo marinus (Linnaeus, 1758) from Morelos state, Mexico. These are new host records extending the known geographical distribution of this species from Brazil and Puerto Rico to Mexico.

  10. [Digenea of Haliaeetus albicilla (Linnaeus, 1758) and Pandion haliaetus (Linnaeus, 1758) from middle and north-western Poland].

    PubMed

    Kalisińska, Elzbieta; Rzad, Izabella; Sitko, Jilji; Kavetska, Katarzyna M; Królaczyk, Katarzyna; Budis, Halina

    2008-01-01

    In 2003-2008 eight white-tailed eagles and two ospreys from middle and north-western Poland were examined for the presence of parasites. Nine birds were infected with 5 digenean species: Conodiplostomum perlatum, Paracoenogonimus ovatus, Strigeafalconis, Metorchis crassiusculus and Nematostrigea serpens. M. crassiusculus was found for the first time in an eagle from Poland.

  11. Validation of SWEEP for creep, saltation, and suspension in a desert-oasis ecotone

    USDA-ARS?s Scientific Manuscript database

    Wind erosion in the desert-oasis ecotone can accelerate desertification and thus impacts oasis ecological security. Little is known about the susceptibility of the desert-oasis ecotone to wind erosion in the Tarim Basin even though the ecotone is a major source of windblown dust in China. The object...

  12. Velocity of motion across the skin influences perception of tactile location.

    PubMed

    Nguyen, Elizabeth H L; Taylor, Janet L; Brooks, Jack; Seizova-Cajic, Tatjana

    2016-02-01

    We investigated the influence of motion context on tactile localization, using a paradigm similar to the cutaneous rabbit or sensory saltation (Geldard FA, Sherrick CE. Science 178: 178-179, 1972). In one of its forms, the rabbit stimulus consists of a tap in one location quickly followed by another tap elsewhere, creating the illusion that the two taps are near each other. Instead of taps, we used position of a halted brush and instead of distance judgment, localization responses. The brush moved across the skin of the left forearm, creating a clear motion signal before and after a rabbitlike leap of 10 cm (at 100 cm/s). Three before-and-after velocities (7.5, 15, or 30 cm/s) were used. Participants (n = 13) pointed with their right arm at the felt location of the brush when it halted either 1 cm before or after the leap. These stops were 12 cm apart, but distances computed from localization responses were only 5.4, 6.5, and 7.5 cm for the three velocities, respectively (F[2,11] = 15.19, P = 0.001). Thus the leap resulted in compressive position shift, as described previously for sensory saltation, but modulated by motion velocity before the leap: the slower the motion, the greater the shift opposite to motion direction. No gap in stimulation was perceived. We propose that velocity extrapolation causes the position shift: extrapolated motion does not have enough time to bridge the real spatial gap and thus assigns a closer location to the skin on the opposite side of the gap. Copyright © 2016 the American Physiological Society.

  13. Comment on ``Minimal size of a barchan dune''

    NASA Astrophysics Data System (ADS)

    Andreotti, B.; Claudin, P.

    2007-12-01

    It is now an accepted fact that the size at which dunes form from a flat sand bed as well as their “minimal size” scales on the flux saturation length. This length is by definition the relaxation length of the slowest mode toward equilibrium transport. The model presented by Parteli, Durán, and Herrmann [Phys. Rev. E 75, 011301 (2007)] predicts that the saturation length decreases to zero as the inverse of the wind shear stress far from the threshold. We first show that their model is not self-consistent: even under large wind, the relaxation rate is limited by grain inertia and thus cannot decrease to zero. A key argument presented by these authors comes from the discussion of the typical dune wavelength on Mars (650 m) on the basis of which they refute the scaling of the dune size with the drag length evidenced by Claudin and Andreotti [Earth Planet. Sci. Lett. 252, 30 (2006)]. They instead propose that Martian dunes, composed of large grains (500μm) , were formed in the past under very strong winds. We emphasize that this saltating grain size, estimated from thermal diffusion measurements, is far from straightforward. Moreover, the microscopic photographs taken by the rovers on Martian Aeolian bedforms show a grain size of 87±25μm together with hematite spherules at millimeter scale. As those so-called “blueberries” cannot be entrained more frequently than a few hours per century, we conclude that the saltating grains on Mars are the small ones, which gives a second strong argument against the model of Parteli

  14. Reply to ``Comment on `Minimal size of a barchan dune' ''

    NASA Astrophysics Data System (ADS)

    Parteli, E. J. R.; Durán, O.; Herrmann, H. J.

    2007-12-01

    We reply to the preceding comment by Andreotti and Claudin [Phys. Rev. E 76, 063301 (2007)] on our paper [Phys. Rev. E 75, 011301 (2007)]. We show that the equations of the dune model used in our calculations are self-consistent and effectively lead to a dependence of the minimal dune size on the wind speed through the saturation length. Furthermore, we show that Meridiani Planum ripples are probably not a good reference to estimate the grain size of Martian dune sands: the soil in the ripple troughs at the landing site is covered with nonerodible elements (“blueberries”), which increase the minimal threshold for saltation by a factor of 2.0. We conclude that, in the absence of large fragments as the ones found at the landing site, basaltic grains of diameter d=500±100μm that compose the large, typical dark Martian dunes [K. S. Edgett and P. R. Christensen, J. Geophys. Res. 96, 22765 (1991)] probably saltate during the strongest storms on Mars. We also show that the wind friction speed u∗≈3.0m/s that we found from the calculations of Martian dunes is within the values of maximum wind speeds that occur during Martian storms a few times a decade [R. E. Arvidson , Science 222, 463 (1983); H. J. Moore, J. Geophys. Res. 90, 163 (1985); R. Sullivan , Nature (London) 436, 58 (2005); D. J. Jerolmack , J. Geophys. Res. 111, E12S02 (2006)]. In this manner, the dune model predicts that Martian dunes can be formed under present Martian conditions, with no need to assume other conditions of wind and atmosphere that could have prevailed in the past.

  15. Wind tunnel experiments: influence of erosion and deposition on wind-packing of new snow

    NASA Astrophysics Data System (ADS)

    Sommer, Christian G.; Lehning, Michael; Fierz, Charles

    2018-01-01

    Wind sometimes creates a hard, wind-packed layer at the surface of a snowpack. The formation of such wind crusts was observed during wind tunnel experiments with combined SnowMicroPen and Microsoft Kinect sensors. The former provides the hardness of new and wind-packed snow and the latter spatial snow depth data in the test section. Previous experiments showed that saltation is necessary but not sufficient for wind-packing. The combination of hardness and snow depth data now allows to study the case with saltation in more detail. The Kinect data requires complex processing but with the appropriate corrections, snow depth changes can be measured with an accuracy of about 1 mm. The Kinect is therefore well suited to quantify erosion and deposition. We found that no hardening occurred during erosion and that a wind crust may or may not form when snow is deposited. Deposition is more efficient at hardening snow in wind-exposed than in wind-sheltered areas. The snow hardness increased more on the windward side of artificial obstacles placed in the wind tunnel. Similarly, the snow was harder in positions with a low Sx parameter. Sx describes how wind-sheltered (high Sx) or wind-exposed (low Sx) a position is and was calculated based on the Kinect data. The correlation between Sx and snow hardness was -0.63. We also found a negative correlation of -0.4 between the snow hardness and the deposition rate. Slowly deposited snow is harder than a rapidly growing accumulation. Sx and the deposition rate together explain about half of the observed variability of snow hardness.

  16. Aeolian sand transport over complex intertidal bar-trough beach topography

    NASA Astrophysics Data System (ADS)

    Anthony, Edward J.; Ruz, Marie-Hélène; Vanhée, Stéphane

    2009-04-01

    Aeolian sand transport on macrotidal beaches with complex intertidal bar-trough topography (ridge-and-runnel beaches) was assessed from experiments in northern France that involved measurements of wind speed, saltation, surface moisture contents, and rates of sand trapping across surveyed portions of the upper beach profile. Beaches exhibiting intertidal bars and troughs are much more complex, topographically, than simple reflective or dissipative beaches. Furthermore, the intertidal bar-trough morphology commonly exhibits strong cross-shore variations in the moisture contents of the beach surface and in patterns of bedform development. The results of four 30-minute experiments, conducted along topographically surveyed portions of the upper beach-dune toe profile, show that troughs act as extremely efficient sand interceptors, because of their permanently saturated state, which also inhibits sand mobilisation. Troughs, thus, limit or segment the dry fetch during conditions of intermittent saltation. Flow lines, inferred from the wind profiles, suggest that complex interactions at the boundary layer are generated by the bar-trough topography. Troughs systematically appear to be characterised by air expansion, while bar faces generate ramp wind acceleration for onshore winds, and sometimes immediate downwind deceleration for offshore winds. These effects may also contribute to cross-shore variations in the rates of sand trapping. Finally, a simple conceptual model of effective fetch development, integrating the effects of the spring-neap tidal range and of gross bar-trough morphological variability over time, is proposed for bar-trough beaches. The model highlights the key theme of fetch segmentation induced by cross-shore differentiation in the moisture contents of the beach surface hinged on the complex topography of multiple bars and troughs.

  17. Effect of roughness formulation on the performance of a coupled wave, hydrodynamic, and sediment transport model

    USGS Publications Warehouse

    Ganju, Neil K.; Sherwood, Christopher R.

    2010-01-01

    A variety of algorithms are available for parameterizing the hydrodynamic bottom roughness associated with grain size, saltation, bedforms, and wave–current interaction in coastal ocean models. These parameterizations give rise to spatially and temporally variable bottom-drag coefficients that ostensibly provide better representations of physical processes than uniform and constant coefficients. However, few studies have been performed to determine whether improved representation of these variable bottom roughness components translates into measurable improvements in model skill. We test the hypothesis that improved representation of variable bottom roughness improves performance with respect to near-bed circulation, bottom stresses, or turbulence dissipation. The inner shelf south of Martha’s Vineyard, Massachusetts, is the site of sorted grain-size features which exhibit sharp alongshore variations in grain size and ripple geometry over gentle bathymetric relief; this area provides a suitable testing ground for roughness parameterizations. We first establish the skill of a nested regional model for currents, waves, stresses, and turbulent quantities using a uniform and constant roughness; we then gauge model skill with various parameterization of roughness, which account for the influence of the wave-boundary layer, grain size, saltation, and rippled bedforms. We find that commonly used representations of ripple-induced roughness, when combined with a wave–current interaction routine, do not significantly improve skill for circulation, and significantly decrease skill with respect to stresses and turbulence dissipation. Ripple orientation with respect to dominant currents and ripple shape may be responsible for complicating a straightforward estimate of the roughness contribution from ripples. In addition, sediment-induced stratification may be responsible for lower stresses than predicted by the wave–current interaction model.

  18. Neural Models of Spatial Orientation in Novel Environments

    DTIC Science & Technology

    1994-01-01

    tool use, the problem of self-organizing body -centered spatial representations for movement planning and spatial orientation, and the problem of...meeting of the American Association for the Advancement of Science, Boston, February, 1993. 23. Grossberg, S., annual Linnaeus Lecture, Uppsala...Congress on Neural Networks entitled --A self-organizing neural network for learning a body -centered invariant representa- tion of 3-D target

  19. Selection of active strains of the gypsy moth nuclearpolyhedrosis virus

    Treesearch

    M. Shapiro; E. Dougherty

    1985-01-01

    The gypsy moth Lymantria dispar (Linnaeus) has grown in economic importance as an insect pest over the past 75 years. From a localized infestation of a small geographical area of New England, the gypsy moth has spread to such an extent that is now found over much of the United States. Control measures are varied, but effective biological control is...

  20. Recent Aeolian Dune Change on Mars

    NASA Technical Reports Server (NTRS)

    Bourke, M. C.; Edgett, K. S.; Cantor, B. A.

    2007-01-01

    Previous comparisons of Martian aeolian dunes in satellite images have not detected any change in dune form or position. Here, we show dome dunes in the north polar region that shrank and then disappeared over a period of 3.04 Mars years (5.7 Earth years), while larger, neighboring dunes showed no erosion or movement. The removal of sand from these dunes indicates that not only is the threshold wind speed for saltation exceeded under present conditions on Mars, but that any sand that is available for transport is likely to be moved. Dunes that show no evidence of change could be crusted, indurated. or subject to infrequent episodes of movement.

  1. The physics of wind-blown sand and dust

    NASA Astrophysics Data System (ADS)

    Kok, Jasper F.; Parteli, Eric J. R.; Michaels, Timothy I.; Karam, Diana Bou

    2012-10-01

    The transport of sand and dust by wind is a potent erosional force, creates sand dunes and ripples, and loads the atmosphere with suspended dust aerosols. This paper presents an extensive review of the physics of wind-blown sand and dust on Earth and Mars. Specifically, we review the physics of aeolian saltation, the formation and development of sand dunes and ripples, the physics of dust aerosol emission, the weather phenomena that trigger dust storms, and the lifting of dust by dust devils and other small-scale vortices. We also discuss the physics of wind-blown sand and dune formation on Venus and Titan.

  2. The physics of wind-blown sand and dust.

    PubMed

    Kok, Jasper F; Parteli, Eric J R; Michaels, Timothy I; Karam, Diana Bou

    2012-10-01

    The transport of sand and dust by wind is a potent erosional force, creates sand dunes and ripples, and loads the atmosphere with suspended dust aerosols. This paper presents an extensive review of the physics of wind-blown sand and dust on Earth and Mars. Specifically, we review the physics of aeolian saltation, the formation and development of sand dunes and ripples, the physics of dust aerosol emission, the weather phenomena that trigger dust storms, and the lifting of dust by dust devils and other small-scale vortices. We also discuss the physics of wind-blown sand and dune formation on Venus and Titan.

  3. Soils of eagle crater and Meridiani Planum at the opportunity Rover landing site

    USGS Publications Warehouse

    Soderblom, L.A.; Anderson, R.C.; Arvidson, R. E.; Bell, J.F.; Cabrol, N.A.; Calvin, W.; Christensen, P.R.; Clark, B. C.; Economou, T.; Ehlmann, B.L.; Farrand, W. H.; Fike, D.; Gellert, Ralf; Glotch, T.D.; Golombek, M.P.; Greeley, R.; Grotzinger, J.P.; Herkenhoff, K. E.; Jerolmack, D.J.; Johnson, J. R.; Jolliff, B.; Klingelhofer, C.; Knoll, A.H.; Learner, Z.A.; Li, R.; Malin, M.C.; McLennan, S.M.; McSween, H.Y.; Ming, D. W.; Morris, R.V.; Rice, J. W.; Richter, L.; Rieder, R.; Rodionov, D.; Schroder, C.; Seelos, F.P.; Soderblom, J.M.; Squyres, S. W.; Sullivan, R.; Watters, W.A.; Weitz, C.M.; Wyatt, M.B.; Yen, A.; Zipfel, J.

    2004-01-01

    The soils at the Opportunity site are fine-grained basaltic sands mixed with dust and sulfate-rich outcrop debris. Hematite is concentrated in spherules eroded from the strata. Ongoing saltation exhumes the spherules and their fragments, concentrating them at the surface. Spherules emerge from soils coated, perhaps from subsurface cementation, by salts. Two types of vesicular clasts may represent basaltic sand sources. Eolian ripples, armored by well-sorted hematite-rich grains, pervade Meridiani Planum. The thickness of the soil on the plain is estimated to be about a meter. The flatness and thin cover suggest that the plain may represent the original sedimentary surface.

  4. The Biology and Control of the Greater Wax Moth, Galleria mellonella.

    PubMed

    Kwadha, Charles A; Ong'amo, George O; Ndegwa, Paul N; Raina, Suresh K; Fombong, Ayuka T

    2017-06-09

    The greater wax moth, Galleria mellonella Linnaeus , is a ubiquitous pest of the honeybee, Apis mellifera Linnaeus, and Apis cerana Fabricius . The greater wax moth larvae burrow into the edge of unsealed cells with pollen, bee brood, and honey through to the midrib of honeybee comb. Burrowing larvae leave behind masses of webs which causes galleriasis and later absconding of colonies. The damage caused by G. mellonella larvae is severe in tropical and sub-tropical regions, and is believed to be one of the contributing factors to the decline in both feral and wild honeybee populations. Previously, the pest was considered a nuisance in honeybee colonies, therefore, most studies have focused on the pest as a model for in vivo studies of toxicology and pathogenicity. It is currently widespread, especially in Africa, and the potential of transmitting honeybee viruses has raised legitimate concern, thus, there is need for more studies to find sustainable integrated management strategies. However, our knowledge of this pest is limited. This review provides an overview of the current knowledge on the biology, distribution, economic damage, and management options. In addition, we provide prospects that need consideration for better understanding and management of the pest.

  5. Phlorotannin Extracts from Fucales Characterized by HPLC-DAD-ESI-MSn: Approaches to Hyaluronidase Inhibitory Capacity and Antioxidant Properties

    PubMed Central

    Ferreres, Federico; Lopes, Graciliana; Gil-Izquierdo, Angel; Andrade, Paula B.; Sousa, Carla; Mouga, Teresa; Valentão, Patrícia

    2012-01-01

    Purified phlorotannin extracts from four brown seaweeds (Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira tamariscifolia (Hudson) Papenfuss, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus), were characterized by HPLC-DAD-ESI-MSn. Fucophloroethol, fucodiphloroethol, fucotriphloroethol, 7-phloroeckol, phlorofucofuroeckol and bieckol/dieckol were identified. The antioxidant activity and the hyaluronidase (HAase) inhibitory capacity exhibited by the extracts were also assessed. A correlation between the extracts activity and their chemical composition was established. F. spiralis, the species presenting higher molecular weight phlorotannins, generally displayed the strongest lipid peroxidation inhibitory activity (IC50 = 2.32 mg/mL dry weight) and the strongest HAase inhibitory capacity (IC50 = 0.73 mg/mL dry weight). As for superoxide radical scavenging, C. nodicaulis was the most efficient species (IC50 = 0.93 mg/mL dry weight), followed by F. spiralis (IC50 = 1.30 mg/mL dry weight). These results show that purified phlorotannin extracts have potent capabilities for preventing and slowing down the skin aging process, which is mainly associated with free radical damage and with the reduction of hyaluronic acid concentration, characteristic of the process. PMID:23222802

  6. Nom et lumière: enlightenment through nomenclature (the 1996 Kenneth F. Russell Memorial Lecture).

    PubMed

    Pearn, J

    1997-08-01

    The classification of living things is both an acknowledgement of biological relationships and an identification of their differences. When Linnaeus, in 1735, published Systema Naturae, he set in place a system of biological classification that saw its apogee in the invention of binomial nomenclature: the description of every living thing being embodied simply in two names, (i.e. a genus and the species within it). Linnaeus built on the work of scientific forebears, of whom Nehemiah Grew (1641-1712) was one of the most influential. Grew was a surgeon-physician whose passionate interest was plant anatomy; his work led to the discovery and documentation of sexual dimorphism in plants. Grew's life and works are a witness to that philosophy which views nature as a continuum, a broad holistic entity in which discoveries in one biological field have ramifications in other areas. Grew allowed his scientific curiosity full rein, manifested the courage to publish his work and possessed the self-discipline to stand by the audit of his peers. Modern biological research and contemporary clinical practice owes much to the enlightenment engendered by the classification and nomenclature that developed from his work.

  7. Natural hazards at the southern margin of the Central Anatolian Plateau (CAP) (southern Turkey): Tsunami evidence

    NASA Astrophysics Data System (ADS)

    Ogretmen, Nazik; Cosentino, Domenico; Gliozzi, Elsa; Cipollari, Paola; Radeff, Giuditta; Yıldırım, Cengiz

    2016-04-01

    In regions that are located in steep, orogenic plateau margins, such as the coastal area of the Central Anatolian Plateau (CAP) southern margin, natural hazard studies related to active tectonics and events that are triggered by active tectonics (e.g., earthquakes, landslides, tsunamis) are very essential in the context of preventing possible damages. This work herein, represents some evidence of the tsunami hazard along the coast between Aydıncık and Narlıkuyu, in southern Turkey. The work is based on a study on out-of-place beachrock-slab boulder acummulation in Aydıncık district, which were transported onshore by sliding process, and on out-of-place more rounded boulders that were transported by saltation process in Narlıkuyu and Yeşilovacık districts. The presence of intertidal organisms (e.g., lithophaga boring, balanids, oysters, etc.) encrusting the boulders of both localities shows that those boulders were carried onland from a marine environment. According to their dimensions and weight, in agreement with out-of-place boulders from areas surely affected by tsunamis, those out-of-place boulders here are interpreted as due to tsunami waves. The tsunamites in the Aydıncık area are located on beachrock slabs. They are platty and some of those blocks are embricated and oriented perpendicular to the shoreline (NE-SW direction). Those boulders have been interpreted as transported by sliding process, in relation with the coastal morphology and the boulder geometry, which means that to move those boulders the energy of the tsunami not necessarily should have been as high as in saltation or rolling transport processes. On the contrary, in Narlıkuyu and Yeşilovacık localities, the boulders are well-rounded and ellipsoidal shaped, suggesting that they were transported by rolling and/or saltation mode rather than by sliding. To carry onland the tsunami boulders observed in the Narlıkuyu and Yeşilovacık districts, which in the Yeşilovacık area they are

  8. A new species of Haliotis (Gastropoda) from São Tomé & Príncipe Islands, Gulf of Guinea, with comparisons to other Haliotis found in the Eastern Atlantic and Mediterranean.

    PubMed

    Owen, Buzz

    2014-07-16

    The Haliotidae from the Gulf of Guinea, West Africa are reviewed. The distribution of the mainland species Haliotis marmorata Linnaeus, 1758 is confirmed and compared to the insular species from the island nation of São Tomé and Príncipe which is described as Haliotis geigeri n. sp. Both species are illustrated and compared to the other known Haliotidae from the eastern Atlantic.

  9. Two new species of the genus Anthaxia (Anthaxia Eschscholtz 1829) from China, and notes on the related species (Coleoptera: Buprestidae: Anthaxiini).

    PubMed

    Bílý, Svatopluk

    2015-06-04

    Anthaxia (Anthaxia) kmoniceki sp. nov. and Anthaxia (Anthaxia) ungulata sp. nov. (China, Sichuan) both belonging to the A. (A.) nitidula Linnaeus, 1758 species-group are described, illustrated and compared with the most similar species. A short description of the male and new records of Anthaxia (A.) nitiduliformis Bílý, 1995 are given together with the notes on the bionomy of the species-group.

  10. Colaspis caligula, a new species found in association with Vitis vinifera (L.) crops in Argentina (Coleoptera: Chrysomelidae).

    PubMed

    Agrain, Federico A; Cabrera, Nora; Holgado, Miriam G; Vicchi, Franco R

    2016-09-05

    Some species of Colaspis Fabricius are well-known pests of several crops in Argentina. In this contribution, we describe a new species within this genus: Colaspis caligula n. sp., found in association with Vitis vinifera (Linnaeus) crops. We provide descriptions and illustrations of the mature larva, pupa and adult, as well as notes on its diagnostic characters, life cycle, and the damages produced to the plants.

  11. Karyotypes of some medium-sized Dytiscidae (Agabinae and Colymbetinae) (Coleoptera)

    PubMed Central

    Angus, Robert B.; Clery, Molly J.; Carter, Jodie C.; Wenczek, Daniel E.

    2013-01-01

    Abstract An account is given of the karyotypes of 29 species of medium sized Dytiscidae (Coleoptera). Of the 20 species of Agabus Leach, 1817, 18 have karyotypes comprising 21 pairs of autosomes and sex chromosomes which are either X0(♂) or XX (♀). These species are Agabus serricornis (Paykull, 1799), Agabus labiatus (Brahm, 1791), Agabus congener (Thunberg, 1794), Agabus lapponicus (Thomson, 1867), Agabus thomsoni (J. Sahlberg, 1871), Agabus confinis (Gyllenhal, 1808), Agabus sturmii (Gyllenhal, 1808), Agabus bipustulatus (Linnaeus, 1767), Agabus nevadensis Håkan Lindberg, 1939, Agabus wollastoni Sharp, 1882, Agabus melanarius Aubé, 1837, Agabus biguttatus (Olivier, 1795), Agabus binotatus Aubé, 1837, Agabus affinis (Paykull, 1798), Agabus unguicularis (Thomson, 1867), Agabus ramblae Millan & Ribera, 2001, Agabus conspersus (Marsham, 1802) and Agabus nebulosus (Forster, 1771). However two species, Agabus infuscatus Aubé, 1838 and Agabus adpressus Aubé, 1837, have developed a neo-XY system, with karyotypes comprising 21 pairs of autosomes and XY sex chromosomes (♂). No chromosomal differences have been detected between typical Agabus bipustulatus and Agabus bipustulatus var. solieri Aubé, 1837, nor have any been found between the three species of the Agabus bipustulatus complex (Agabus bipustulatus, Agabus nevadensis and Agabus wollastoni). The four species of Colymbetes Clairville, 1806, Colymbetes fuscus (Linnaeus, 1758), Colymbetes paykulli Erichson, 1837, Colymbetes piceus Klug, 1834 and Colymbetes striatus (Linnaeus, 1758) have karyotypes comprising 20 pairs of autosomes and sex chromosomes which are X0 (♂), XX (♀). Two of the species of Rhantus Dejean, 1833, Rhantus exsoletus (Forster, 1771) and Rhantus suturellus (Harris, 1828) have karyotypes comprising 20 pairs of autosomes and X0/XX sex chromosomes, but the other three species, Rhantus grapii (Gyllenhal, 1808), Rhantus frontalis (Marsham, 1802) and Rhantus suturalis (Macleay, 1825) have 22

  12. Assimilation efficiencies and turnover rates of trace elements in marine bivalves: A comparison of oysters, clams and mussels

    USGS Publications Warehouse

    Reinfelder, J.R.; Wang, W.-X.; Luoma, S. N.; Fisher, N.S.

    1997-01-01

    Assimilation efficiencies (AEs) and physiological turnover-rate constants (k) of six trace elements (Ag, Am, Cd, Co, Se, Zn) in four marine bivalves (Crassostrea virginica Gmelin,Macoma balthica Linnaeus, Mercenaria mercenaria Linnaeus, and Mytilus edulis Linnaeus) were measured in radiotracer-depuration experiments. Egestion rates of unassimilated elements were highest during the first 24 h of depuration and declined thereafter. Significant egestion of unassimilated Co, however, continued for up to 5 d in Macoma balthica,Mercenaria mercenaria and Mytilus edulis. With the exception of the extremely low values for110 mAg, 109Cd, and 65Zn in C. virginica, physiological turnover-rate constants (k) showed no general pattern of variation among elements, bivalve species or food types, and were relatively invariant. Values from  ≤0.001 to 0.1 d−1 were observed, but excluding those for Co, most values were  ≤0.04 d−1. In all four species, the AEs of Ag, Am, and Co were generally lower than those of Cd, Se, and Zn. The AEs of Ag, Cd, Se, and Zn in these bivalves are directly related to the proportion of each element in the cytoplasmic fraction of ingested phytoplankton, indicating that >80% of elements in a prey alga's cytoplasm was assimilated. C. virginica, Macoma balthica, and Mercenaria mercenaria assimilated ∼36% of the Ag and Cd associated with the non-cytoplasmic (membrane/organelle) fraction of ingested cells in addition to the cytoplasmic fraction. The ratio of AE:k, which is proportional to the consumer–prey trace-element bioaccumulation factor (concentration in consumer:concentration in prey) was generally greater for Cd, Se, and Zn than for Ag, Am, and Co. This ratio was lowest in Mytilus edulis, suggesting that this bivalve, the most widely employed organism in global biomonitoring, is relatively inefficient at accumulating important elements such as Ag, Cd, and Zn from ingested phytoplankton.

  13. Ordination of breeding birds in relation to environmental gradients in three southeastern United States floodplain forests

    USGS Publications Warehouse

    Wakeley, J.S.; Guilfoyle, M.P.; Antrobus, T.J.; Fischer, R.A.; Barrow, W.C.; Hamel, P.B.

    2007-01-01

    We used an ordination approach to identify factors important to the organization of breeding bird communities in three floodplains: Cache River, Arkansas (AR), Iatt Creek, Louisiana (LA), and the Coosawhatchie River, South Carolina (SC), USA. We used 5-min point counts to sample birds in each study area each spring from 1995 to 1998, and measured ground-surface elevations and a suite of other habitat variables to investigate bird distributions and community characteristics in relation to important environmental gradients. In both AR and SC, the average number of Neotropical migrant species detected was lowest in semipermanently flooded Nyssa aquatica Linnaeus habitats and greatest in the highest elevation floodplain zone. Melanerpes carolinus Linnaeus, Protonotaria citrea Boddaert, Quiscalus quiscula Linnaeus, and other species were more abundant in N. aquatica habitats, whereas Wilsonia citrina Boddaert, Oporornis formosus Wilson, Vireo griseus Boddaert, and others were more abundant in drier floodplain zones. In LA, there were no significant differences in community metrics or bird species abundances among forest types. Canonical correspondence analyses revealed that structural development of understory vegetation was the most important factor affecting bird distributions in all three study areas; however, potential causes of these structural gradients differed. In AR and SC, differences in habitat structure were related to the hydrologic gradient, as indexed by ground-surface elevation. In LA, structural variations were related mainly to the frequency of canopy gaps. Thus, bird communities in all three areas appeared to be organized primarily in response to repeated localized disturbance. Our results suggest that regular disturbance due to flooding plays an important role in structuring breeding bird communities in floodplains subject to prolonged inundation, whereas other agents of disturbance (e.g., canopy gaps) may be more important in headwater systems

  14. Connecting meteorology to surface transport in aeolian landscapes: Peering into the boundary layer with Doppler lidar

    NASA Astrophysics Data System (ADS)

    Gunn, A.; Jerolmack, D. J.; Edmonds, D. A.; Ewing, R. C.; Wanker, M.; David, S. R.

    2017-12-01

    Aolian sand dunes grow to 100s or 1000s of meters in wavelength by sand saltation, which also produces dust plumes that feed cloud formation and may spread around the world. The relations among sediment transport, landscape dynamics and wind are typically observed at the limiting ends of the relevant range: highly resolved and localized ground observations of turbulence and relevant fluxes; or regional and synoptic-scale meteorology and satellite imagery. Between the geostrophic winds aloft and shearing stress on the Earth's surface is the boundary layer, whose stability and structure determines how momentum is transferred and ultimately entrains sediment. Although the literature on atmospheric boundary layer flows is mature, this understanding is rarely applied to aeolian landscape dynamics. Moreover, there are few vertically and time-resolved datasets of atmospheric boundary layer flows in desert sand seas, where buoyancy effects are most pronounced. Here we employ a ground-based upward-looking doppler lidar to examine atmospheric boundary layer flow at the upwind margin of the White Sands (New Mexico) dune field, providing continuous 3D wind velocity data from the surface to 300-m aloft over 70 days of the characteristically windy spring season. Data show highly resolved daily cyles of convective instabilty due to daytime heating and stable stratification due to nightime cooling which act to enhance or depress, respectively, the surface wind stresses for a given free-stream velocity. Our data implicate convective instability in driving strong saltation and dust emission, because enhanced mixing flattens the vertical velocity profile (raising surface wind speed) while upward advection helps to deliver dust to the high atmosphere. We also find evidence for Ekman spiralling, with a magnitude that depends on atmospheric stability. This spiralling gives rise to a deflection in the direction between geostrophic and surface winds, that is significant for the

  15. Particle transport patterns of short-distance soil erosion by wind-driven rain, rain and wind

    NASA Astrophysics Data System (ADS)

    Marzen, Miriam; Iserloh, Thomas; de Lima, João L. M. P.; Ries, Johannes B.

    2015-04-01

    Short distance erosion of soil surface material is one of the big question marks in soil erosion studies. The exact measurement of short-distance transported soil particles, prior to the occurrence of overland flow, is a challenge to soil erosion science due to the particular requirements of the experimental setup and test procedure. To approach a quantification of amount and distance of each type of transport, we applied an especially developed multiple-gutter system installed inside the Trier Portable Wind and Rainfall Simulator (PWRS). We measured the amount and travel distance of soil particles detached and transported by raindrops (splash), wind-driven rain (splash-saltation and splash-drift) and wind (saltation). The test setup included three different erosion agents (rain/ wind-driven rain/ wind), two substrates (sandy/ loamy), three surface structures (grain roughness/ rills lengthwise/ rills transversal) and three slope angles (0°/+7°/-7°). The results present detailed transport patterns of the three erosion agents under the varying soil and surface conditions up to a distance of 1.6 m. Under the applied rain intensity and wind velocity, wind-driven rain splash generates the highest erosion. The erodibility and travel distance of the two substrates depend on the erosion agent. The total erosion is slightly higher for the slope angle -7° (downslope), but for wind-driven rain splash, the inclination is not a relevant factor. The effect of surface structures (rills) changes with traveling distance. The wind driven rain splash generates a much higher amount of erosion and a further travel distance of the particles due to the combined action of wind and rain. The wind-driven rain factor appears to be much more significant than the other factors. The study highlights the effects of different erosion agents and surface parameters on short-distance particle transport and the powerful impact of wind-driven rain on soil erosion.

  16. The sedimentology and dynamics of crater-affiliated wind streaks in western Arabia Terra, Mars and Patagonia, Argentina

    USGS Publications Warehouse

    Rodriguez, J.A.P.; Tanaka, K.L.; Yamamoto, A.; Berman, D.C.; Zimbelman, J.R.; Kargel, J.S.; Sasaki, S.; Jinguo, Y.; Miyamoto, H.

    2010-01-01

    Wind streaks comprise recent aeolian deposits that have been extensively documented on Venus, Earth and Mars. Martian wind streaks are among the most abundant surface features on the planet and commonly extend from the downwind margins of impact craters. Previous studies of wind streaks emerging from crater interior deposits suggested that the mode of emplacement was primarily related to the deposition of silt-sized particles as these settled from plumes. We have performed geologic investigations of two wind streaks clusters; one situated in western Arabia Terra, a region in the northern hemisphere of Mars, and another in an analogous terrestrial site located in southern Patagonia, Argentina, where occurrences of wind streaks emanate from playas within maar craters. In both these regions we have identified bedforms in sedimentary deposits on crater floors, along wind-facing interior crater margins, and along wind streaks. These observations indicate that these deposits contain sand-sized particles and that sediment migration has occurred via saltation from crater interior deposits to wind streaks. In Arabia Terra and in Patagonia wind streaks initiate from crater floors that contain lithic and evaporitic sedimentary deposits, suggesting that the composition of wind streak source materials has played an important role in development. Spatial and topographic analyses suggest that regional clustering of wind streaks in the studied regions directly correlates to the areal density of craters with interior deposits, the degree of proximity of these deposits, and the craters' rim-to-floor depths. In addition, some (but not all) wind streaks within the studied clusters have propagated at comparable yearly (Earth years) rates. Extensive saltation is inferred to have been involved in its propagation based on the studied terrestrial wind streak that shows ripples and dunes on its surface and the Martian counterpart changes orientation toward the downslope direction where it

  17. Behavior of Windblown Sand on Mars: Results From Single-Particle Experiments

    NASA Astrophysics Data System (ADS)

    Marshall, J. R.; Borucki, J.; Sagan, C.

    1996-03-01

    Experiments are investigating the behavior of individual sand grains in the high-energy martian aeolian regime. Energy partitioning during impact of a saltating grain determines grain longevity, but it also influences the way in which the bed becomes mobilized by reptation. When single grains of sand are fired into loose beds, the bed can absorb up to 90% of the impact energy by momentum transfer to other grains; it has been discovered that the impacting grains cause circular craters even at low impact angles. Hundreds of grains can be splashed by a single high-velocity (100 m/s) impact causing more bed disturbance through reptation than previously thought. The research is supported by NASA's PG & G Program.

  18. Turbulent flow structures and aeolian sediment transport over a barchan sand dune

    NASA Astrophysics Data System (ADS)

    Wiggs, G. F. S.; Weaver, C. M.

    2012-03-01

    The turbulent structure of airflow over a barchan sand dune is determined using quadrant analysis of wind velocity data derived from sonic anemometers. Results indicate an increased frequency of ejection and sweep events in the toe region of the dune, characteristic of the turbulent bursting process. In contrast, at the crest there was a significant increase in the occurrence of outward interactions. Combined with high frequency saltation data our analyses show that turbulent structures characterised by a positive streamwise fluctuating velocity (+u‧ sweeps at the toe and outward interactions at the crest) have a dominant influence on sand transport on the dune, together accounting for up to 83% and 95% of transporting events at the toe and crest respectively.

  19. First case of Trichodectes pinguis (Phthiraptera: Ischnocera: Trichodectidae) on a Bear (Ursus arctos) in Turkey.

    PubMed

    Dik, Bilal; Orunç Kılınç, Özlem

    2015-12-01

    This study was conducted to provide morphological characters of Trichodectes pinguis Burmeister, 1838 that was found on a European brown bear (Ursus arctos Linnaeus) that was found injured in the Van province, eastern Turkey. Three lice specimens were collected from the bear, and they were identified as T. pinguis. The morphological characteristics of this species were provided in this study. T. pinguis was reported for the first time in Turkey.

  20. Expression of Wnt signaling skeletal development genes in the cartilaginous fish, elephant shark (Callorhinchus milii).

    PubMed

    D'Souza, Damian G; Rana, Kesha; Milley, Kristi M; MacLean, Helen E; Zajac, Jeffrey D; Bell, Justin; Brenner, Sydney; Venkatesh, Byrappa; Richardson, Samantha J; Danks, Janine A

    2013-11-01

    Jawed vertebrates (Gnasthostomes) are broadly separated into cartilaginous fishes (Chondricthyes) and bony vertebrates (Osteichthyes). Cartilaginous fishes are divided into chimaeras (e.g. ratfish, rabbit fish and elephant shark) and elasmobranchs (e.g. sharks, rays and skates). Both cartilaginous fish and bony vertebrates are believed to have a common armoured bony ancestor (Class Placodermi), however cartilaginous fish are believed to have lost bone. This study has identified and investigated genes involved in skeletal development in vertebrates, in the cartilaginous fish, elephant shark (Callorhinchus milii). Ctnnb1 (β-catenin), Sfrp (secreted frizzled protein) and a single Sost or Sostdc1 gene (sclerostin or sclerostin domain-containing protein 1) were identified in the elephant shark genome and found to be expressed in a number of tissues, including cartilage. β-catenin was also localized in several elephant shark tissues. The expression of these genes, which belong to the Wnt/β-catenin pathway, is required for normal bone formation in mammals. These findings in the cartilaginous skeleton of elephant shark support the hypothesis that the common ancestor of cartilaginous fishes and bony vertebrates had the potential for making bone. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  1. Digenea parasites of Acestrorhynchus falcirostris (Osteichthyes, Acestrorhynchidae) in the state of Amazonas, Brazil.

    PubMed

    Fernandes, Berenice Maria Musco; Justo, Marcia Cristina Nascimento; Anjos, Camila Saraiva Dos; Malta, José Celso de Oliveira; Dumbo, José Chissiua

    2017-01-01

    This study presents the helminthofauna of digenean parasites of Acestrorhynchus falcirostris in the state of Amazonas (Brazil). Eight species belonging to four families were recovered: Metacercariae of Austrodiplostomum compactum (Diplostomidae) and Clinostomum marginatum (Clinostomidae) and mature specimens of Bellumcorpus majus, Prosorhynchoides carvajali, Rhipidocotyle santanaensis (Bucephalidae); Prosthenhystera obesa (Callodistomidae); Genarchella genarchella (Derogenidae) and Phyllodistomum spatula (Gorgoderidae). Examining specimens belonging to the genus Bellumcorpus collected from A. falcirostris, were observed a great variation in the size and shape of testes, which also could be observed in the type specimens of Bellumcorpus majus and B. schubarti. Considering the similar morphology and morphometric characteristics of both species, in this paper B. schubarti is considered synonym of B. majus. Acestrorhynchus falcirostris is a new host records for all these species of digenean, except to A. compactum and C. marginatum. Prosorhynchoides carvajali is referred for the first time in Brazil.

  2. Structure and Possible Functions of Constant-Frequency Calls in Ariopsis seemanni (Osteichthyes, Ariidae)

    PubMed Central

    Schmidtke, Daniel; Schulz, Jochen; Hartung, Jörg; Esser, Karl-Heinz

    2013-01-01

    In the 1970s, Tavolga conducted a series of experiments in which he found behavioral evidence that the vocalizations of the catfish species Ariopsis felis may play a role in a coarse form of echolocation. Based on his findings, he postulated a similar function for the calls of closely related catfish species. Here, we describe the physical characteristics of the predominant call-type of Ariopsis seemanni. In two behavioral experiments, we further explore whether A. seemanni uses these calls for acoustic obstacle detection by testing the hypothesis that the call-emission rate of individual fish should increase when subjects are confronted with novel objects, as it is known from other vertebrate species that use pulse-type signals to actively probe the environment. Audio-video monitoring of the fish under different obstacle conditions did not reveal a systematic increase in the number of emitted calls in the presence of novel objects or in dependence on the proximity between individual fish and different objects. These negative findings in combination with our current understanding of directional hearing in fishes (which is a prerequisite for acoustic obstacle detection) make it highly unlikely that A. seemanni uses its calls for acoustic obstacle detection. We argue that the calls are more likely to play a role in intra- or interspecific communication (e.g. in school formation or predator deterrence) and present results from a preliminary Y-maze experiment that are indicative for a positive phonotaxis of A. seemanni towards the calls of conspecifics. PMID:23741408

  3. Morphohistology of the Digestive Tract of the Damsel Fish Stegastes fuscus (Osteichthyes: Pomacentridae)

    PubMed Central

    Canan, Bhaskara; do Nascimento, Wallace Silva; da Silva, Naisandra Bezerra; Chellappa, Sathyabama

    2012-01-01

    This study investigated the morphohistology of the digestive tract and the mean intestinal coefficient of the damsel fish Stegastes fuscus captured from the tidal pools of Northeastern Brazil. The wall of the digestive tract of S. fuscus is composed of the tunica mucosa, tunica muscularis, and tunica serosa. The esophagus is short with sphincter and thick distensible wall with longitudinally folded mucosa. Mucous glands are predominant, and the muscular layer of the esophagus presented striated fibers all along its extension. The transition region close to the stomach shows plain and striated muscular fibers. Between the stomach and intestine, there are three pyloric caeca. The intestine is long and thin with four folds around the stomach. The anterior intestine presents folds similar to those of pyloric caeca. The estimated mean intestinal coefficient and characteristics of the digestive system of S. fuscus present morphological adequacy for both herbivorous and omnivorous feeding habits. PMID:22547996

  4. [Identification of antler powder components based on DNA barcoding technology].

    PubMed

    Jia, Jing; Shi, Lin-chun; Xu, Zhi-chao; Xin, Tian-yi; Song, Jing-yuan; Chen Shi, Lin

    2015-10-01

    In order to authenticate the components of antler powder in the market, DNA barcoding technology coupled with cloning method were used. Cytochrome c oxidase subunit I (COI) sequences were obtained according to the DNA barcoding standard operation procedure (SOP). For antler powder with possible mixed components, the cloning method was used to get each COI sequence. 65 COI sequences were successfully obtained from commercial antler powders via sequencing PCR products. The results indicates that only 38% of these samples were derived from Cervus nippon Temminck or Cervus elaphus Linnaeus which is recorded in the 2010 edition of "Chinese Pharmacopoeia", while 62% of them were derived from other species. Rangifer tarandus Linnaeus was the most frequent species among the adulterants. Further analysis showed that some samples collected from different regions, companies and prices, contained adulterants. Analysis of 36 COI sequences obtained by the cloning method showed that C. elaphus and C. nippon were main components. In addition, some samples were marked clearly as antler powder on the label, however, C. elaphus or R. tarandus were their main components. In summary, DNA barcoding can accurately and efficiently distinguish the exact content in the commercial antler powder, which provides a new technique to ensure clinical safety and improve quality control of Chinese traditional medicine

  5. Antioxidant Activity, Total Phenolics and Flavonoid Contents of some Edible Green Seaweeds from Northern Coasts of the Persian Gulf.

    PubMed

    Farasat, Massoumeh; Khavari-Nejad, Ramazan-Ali; Nabavi, Seyed Mohammad Bagher; Namjooyan, Foroogh

    2014-01-01

    The antioxidant activity, contents of total phenolics and flavonoids were quantified in the methanolic extracts of four Ulva species (Ulva clathrata (Roth) C.Agardh, Ulva linza Linnaeus, Ulva flexuosa Wulfen and Ulva intestinalis Linnaeus) grown at different parts of northern coasts of the Persian Gulf in south of Iran. The seaweeds were collected from Dayyer, Taheri and Northern Ouli coasts in April 2011. Methanolic extracts of the seaweeds were assessed for their antioxidant activity using DPPH radical scavenging assay and was performed in a microplate reader. All species exhibited a DPPH radical scavenging activity, and among the species, Ulva clathrata demonstrated greater antioxidant potential with a low IC50 (0.881 mg mL(-1)) in comparison with those of the other species. Also the highest phenolic content (5.080 mg GAE g(-1)) and flavonoid content (33.094 mg RE g(-1)) were observed in U.clathrata. Total phenolic and flavonoid contents showed positive correlations with the DPPH radical scavenging activity (p < 0.01) and negative correlations with IC50 (p < 0.01).The results suggest that these edible green seaweeds possess antioxidant potential which could be considered for future applications in medicine, dietary supplements ,cosmetics or food industries.

  6. The evolution of the animals: introduction to a Linnean tercentenary celebration.

    PubMed

    Telford, Maximilian J; Littlewood, D Timothy J

    2008-04-27

    Celebrating 300 years since the birth of Carl Linnaeus (1707-1778), a meeting was held in June 2007 to review recent progress made in understanding the origins and evolutionary radiation of the animals. The year 2008 celebrates the 250th anniversary of the publication of the 10th edition of Linnaeus' Systema Naturae, generally considered to be the starting point of zoological nomenclature. With subsequent advances in comparative taxonomic and systematic studies, Darwin's discovery of evolution by natural selection, the birth of phylogenetic systematics, and the wider interest in biodiversity, it is salutary to consider that many of the major advances in our understanding of animal evolution have been made in recent years. Phylogenetic systematics, drawing from evidence provided by genotype, phenotype and an understanding of the link between them through comparative embryological and evolutionary developmental studies, has provided a wide consensus of the major branching patterns of the tree of life. More importantly, the integrated approaches discussed in the 16 contributions to this volume highlight the identity and nature of problematic taxa, the missing data, errors in existing analytical procedures and the promise of a wealth of additional characters from genomes that need to be accumulated and assessed in providing a definitive Systema Naturae.

  7. A parvicapsulid (Myxozoa) infecting Sprattus sprattus and Clupea harengus (Clupeidae) in the Northeast Atlantic uses Hydroides norvegicus (Serpulidae) as invertebrate host.

    PubMed

    Køie, Marianne; Karlsbakk, Egil; Einen, Ann-Cathrine Bårdsgjtere; Nylund, Are

    2013-05-01

    A myxosporean producing actinospores of the tetractinomyxon type in Hydroides norvegicus Gunnerus (Serpulidae) in Denmark was identified as a member of the family Parvicapsulidae based on small-subunit ribosomal DNA (SSU rDNA) sequences. Myxosporean samples from various Danish and Norwegian marine fishes were examined with primers that detect the novel myxosporean. Sprattus sprattus (Linnaeus) and Clupea harengus Linnaeus (Teleostei, Clupeidae) were found to be infected. The sequences of this parvicapsulid from these hosts were consistently slightly different (0.8% divergence), but both these genotypes were found in H. norvegicus. Disporic trophozoites and minute spores of a novel myxosporean type were observed in the renal tubules of some of the hosts found infected through PCR. The spores appear most similar to those of species of Gadimyxa Køie, Karlsbakk et Nylund, 2007, but are much smaller. The actinospores of the tetractinomyxon type from H. norvegicus have been described previously. In GenBank, the SSU rDNA sequences of Parvicapsulidae gen. sp. show highest identity (82%) with Parvicapsula minibicornis Kent, Whitaker et Dawe, 1997 infecting salmonids (Oncorhynchus spp.) in fresh water in the western North America. A phylogenetic analysis places P. minibicornis and Parvicapsulidae gen. sp. in a sister clade to the other parvicapsulids (Parvicapsula spp. and Gadimyxa spp.).

  8. Cuticle hydrolysis in four medically important fly species by enzymes of the entomopathogenic fungus Conidiobolus coronatus.

    PubMed

    Boguś, M I; Włóka, E; Wrońska, A; Kaczmarek, A; Kazek, M; Zalewska, K; Ligęza-Żuber, M; Gołębiowski, M

    2017-03-01

    Entomopathogenic fungi infect insects via penetration through the cuticle, which varies remarkably in chemical composition across species and life stages. Fungal infection involves the production of enzymes that hydrolyse cuticular proteins, chitin and lipids. Host specificity is associated with fungus-cuticle interactions related to substrate utilization and resistance to host-specific inhibitors. The soil fungus Conidiobolus coronatus (Constantin) (Entomophthorales: Ancylistaceae) shows virulence against susceptible species. The larvae and pupae of Calliphora vicina (Robineau-Desvoidy) (Diptera: Calliphoridae), Calliphora vomitoria (Linnaeus), Lucilia sericata (Meigen) (Diptera: Calliphoridae) and Musca domestica (Linnaeus) (Diptera: Muscidae) are resistant, but adults exposed to C. coronatus quickly perish. Fungus was cultivated for 3 weeks in a minimal medium. Cell-free filtrate, for which activity of elastase, N-acetylglucosaminidase, chitobiosidase and lipase was determined, was used for in vitro hydrolysis of the cuticle from larvae, puparia and adults. Amounts of amino acids, N-glucosamine and fatty acids released were measured after 8 h of incubation. The effectiveness of fungal enzymes was correlated with concentrations of compounds detected in the cuticles of tested insects. Positive correlations suggest compounds used by the fungus as nutrients, whereas negative correlations may indicate compounds responsible for insect resistance. Adult deaths result from the ingestion of conidia or fungal excretions. © 2016 The Royal Entomological Society.

  9. The Biology and Control of the Greater Wax Moth, Galleria mellonella

    PubMed Central

    Kwadha, Charles A.; Ong’amo, George O.; Ndegwa, Paul N.; Raina, Suresh K.; Fombong, Ayuka T.

    2017-01-01

    The greater wax moth, Galleria mellonella Linnaeus, is a ubiquitous pest of the honeybee, Apis mellifera Linnaeus, and Apis cerana Fabricius. The greater wax moth larvae burrow into the edge of unsealed cells with pollen, bee brood, and honey through to the midrib of honeybee comb. Burrowing larvae leave behind masses of webs which causes galleriasis and later absconding of colonies. The damage caused by G. mellonella larvae is severe in tropical and sub-tropical regions, and is believed to be one of the contributing factors to the decline in both feral and wild honeybee populations. Previously, the pest was considered a nuisance in honeybee colonies, therefore, most studies have focused on the pest as a model for in vivo studies of toxicology and pathogenicity. It is currently widespread, especially in Africa, and the potential of transmitting honeybee viruses has raised legitimate concern, thus, there is need for more studies to find sustainable integrated management strategies. However, our knowledge of this pest is limited. This review provides an overview of the current knowledge on the biology, distribution, economic damage, and management options. In addition, we provide prospects that need consideration for better understanding and management of the pest. PMID:28598383

  10. A cascade of warming impacts brings bluefin tuna to Greenland waters.

    PubMed

    MacKenzie, Brian R; Payne, Mark R; Boje, Jesper; Høyer, Jacob L; Siegstad, Helle

    2014-08-01

    Rising ocean temperatures are causing marine fish species to shift spatial distributions and ranges, and are altering predator-prey dynamics in food webs. Most documented cases of species shifts so far involve relatively small species at lower trophic levels, and consider individual species in ecological isolation from others. Here, we show that a large highly migratory top predator fish species has entered a high latitude subpolar area beyond its usual range. Bluefin tuna, Thunnus thynnus Linnaeus 1758, were captured in waters east of Greenland (65°N) in August 2012 during exploratory fishing for Atlantic mackerel, Scomber scombrus Linnaeus 1758. The bluefin tuna were captured in a single net-haul in 9-11 °C water together with 6 tonnes of mackerel, which is a preferred prey species and itself a new immigrant to the area. Regional temperatures in August 2012 were historically high and contributed to a warming trend since 1985, when temperatures began to rise. The presence of bluefin tuna in this region is likely due to a combination of warm temperatures that are physiologically more tolerable and immigration of an important prey species to the region. We conclude that a cascade of climate change impacts is restructuring the food web in east Greenland waters. © 2014 John Wiley & Sons Ltd.

  11. Global assessment of molecularly identified Anisakis Dujardin, 1845 (Nematoda: Anisakidae) in their teleost intermediate hosts.

    PubMed

    Kuhn, Thomas; Hailer, Frank; Palm, Harry W; Klimpel, Sven

    2013-05-01

    Here, we present the ITS ribosomal DNA (rDNA) sequence data on 330 larvae of nematodes of the genus Anisakis Dujardin, 1845 collected from 26 different bony fish species from 21 sampling locations and different climatic zones. New host records are provided for Anisakis simplex (Rudolphi, 1809) sensu stricto (s.s.) and A. pegreffli Campana-Rouget et Biocca, 1955 from Anoplopoma fimbria (Pallas) (Santa Barbara, East Pacific), A. typica (Diesing, 1860) from Caesio cuning (Bloch), Lepturacanthus savala (Cuvier) and Katsuwonus pelamis (Linnaeus) (Indonesia, West Pacific), A. simplex s.s. from Cololabis saira (Brevoort) (Hawaii, Central Pacific), A. simplex C of Nascetti et al. (1986) from Sebastolobus alascanus Bean (Santa Barbara, East Pacific) and A. physeteris Baylis, 1923 from Synaphobranchus kaupii Johnson (Namibia, East Atlantic). Comparison with host records from 60 previous molecular studies of Anisakis species reveals the teleost host range so far recorded for the genus. Perciform (57 species) and gadiform (21) fishes were the most frequently infected orders, followed by pleuronectiforms (15) and scorpaeniforms (15). Most commonly infected fish families were Scombridae (12), Gadidae (10), Carangidae (8) and Clupeidae (7), with Merluccius merluccius (Linnaeus) alone harbouring eight Anisakis species. Different intermediate host compositions implicate differing life cycles for the so far molecularly identified Anisakis sibling species.

  12. Artificial propagation of the sea lamprey Petromyzon marinus

    USGS Publications Warehouse

    Lennon, Robert E.

    1955-01-01

    Observations on the gland products, gonads, and general characteristics of sexually mature sea lampreys, Petromyzon marinus (Linnaeus), from Lake Huron, and a need to obtain some information on very young larval lampreys, prompted an experiment on the stripping and hatching of eggs. Seventeen specimens were selected from a group of spawning migrants which had been trapped in the Ocqueoc River, Michigan, during June and held in live-cars in the lake until early August.

  13. Rock Abrasion and Ventifact Formation on Mars from Field Analog, Theoretical, and Experimental Studies

    NASA Technical Reports Server (NTRS)

    Bridges, N. T.; Laity, J. E.

    2001-01-01

    Rocks observed by the Viking Landers and Pathfinder Lander/Sojourner rover exhibit a suite of perplexing rock textures. Among these are pits, spongy textures, penetrative flutes, lineaments, crusts, and knobs Fluvial, impact, chemical alteration, and aeolian mechanisms have been proposed for many of these. In an effort to better understand the origin and characteristics of Martian rock textures, abraded rocks in the Mojave Desert and other regions have been studied. We find that most Martian rock textures, as opposed to just a few, bear close resemblance to terrestrial aeolian textures and can most easily be explained by wind, not other, processes. Flutes, grooves, and some pits on Mars are consistent with abrasion by saltating particles, as described previously. However, many other rock textures probably also have an aeolian origin. Sills at the base of rocks that generally lie at high elevations, such as Half Dome, are consistent with such features on Earth that are related to moats or soil ramps that shield the basal part of the rock from erosion. Crusts consisting of fluted fabrics, such as those on Stimpy and Chimp, are similar to fluted crusts on Earth that spall off over time. Knobby and lineated rocks are similar to terrestrial examples of heterogeneous rocks that differentially erode. The location of specific rock textures on Mars also gives insight into their origin. Many of the most diagnostic ventifacts found at the Pathfinder site are located on rocks that lie near the crests or the upper slopes of ridges. On Earth, the most active ventifact formation occurs on sloped or elevated topography, where windflow is accelerated and particle kinetic energy and flux are increased. Integrated 0 together, these observations point to significant aeolian 0 modification of rocks on Mars and cast doubt on whether many primary textures resulting from other processes are preserved. Experimental simulations of abrasion in the presence of abundant sand indicate that

  14. Molecular studies on larvae of Pseudoterranova parasite of Trichiurus lepturus Linnaeus, 1758 and Pomatomus saltatrix (Linnaeus, 1766) off Brazilian waters.

    PubMed

    Borges, Juliana N; Cunha, Luiz F G; Miranda, Daniele F; Monteiro-Neto, Cassiano; Santos, Cláudia P

    2015-12-01

    Pseudoterranova larvae parasitizing cutlassfish Trichiurus lepturus and bluefish Pomatomus saltatrix from Southwest Atlantic coast of Brazil were studied in this work by morphological, ultrastructural and molecular approaches. The genetic analysis were performed for the ITS2 intergenic region specific for Pseudoterranova decipiens, the partial 28S (LSU) of ribosomal DNA and the mtDNA cox-1 region. We obtained results for the 28S region and mtDNA cox-1 that was amplified using the polymerase chain reaction and sequenced to evaluate the phylogenetic relationships between sequences of this study and sequences from the GenBank. The morphological profile indicated that all the nine specimens collected from both fish were L3 larvae of Pseudoterranova sp. The genetic profile confirmed the generic level but due to the absence of similar sequences for adult parasites on GenBank for the regions amplifyied, it was not possible to identify them to the species level. The sequences obtained presented 89% of similarity with Pseudoterranova decipiens (28S sequences) and Contracaecum osculatum B (mtDNA cox-1). The low similarity allied to the fact that the amplification with the specific primer for P. decipiens didn't occur, lead us to conclude that our sequences don't belong to P. decipiens complex.

  15. Intermediate hosts of the trematode Collyriclum faba (Plagiochiida: Collyriclidae) identified by an integrated morphological and genetic approach.

    PubMed

    Heneberg, Petr; Faltýnková, Anna; Bizos, Jiří; Malá, Milena; Žiak, Juraj; Literák, Ivan

    2015-02-08

    The cutaneous monostome trematode Collyriclum faba (Bremser in Schmalz, 1831) is a bird parasite with a hitherto unknown life cycle and highly focal occurrence across the Holarctic and Neotropic ecozones. Representative specimens of benthic organisms were sampled at multiple sites and dates within the known foci of C. faba occurrence in Slovakia. A combined approach involving detailed morphological examination and sequencing of two independent DNA loci was used for their analysis. We elucidated the complete life cycle of C. faba, which we determined to include the aquatic gastropod mollusk Bythinella austriaca (Frauenfeld, 1857) as the first intermediate host, the mayflies of the family Heptageniidae, Ecdyonurus venosus (Fabricius, 1775) and Rhithrogena picteti Sowa, 1971 x iridina (Kolenati, 1839), as the second intermediate hosts, and birds (primarily but not exclusively passeriform birds) as the definitive hosts. Bythinella austriaca occurs focally in the springs of tributaries of the Danube in the Alpine-Carpathian region. The restricted distribution of B. austriaca explains the highly focal distribution of C. faba noticed previously in spite of the broad distribution of its second intermediate and definitive host species. Utilization of both larval and adult Ephemeroptera spp. as the second intermediate hosts explains the known spectrum of the definitive host species, with the highest prevalence in species feeding on larvae of Ephemeroptera, such as Cinclus cinclus (Linnaeus, 1758) and Motacilla cinerea Tunstall, 1771, or adults of Ephemeroptera, such as Sylvia atricapilla (Linnaeus, 1758) and Regulus regulus (Linnaeus, 1758). In this study, we also determine the prevalence and DNA sequences of other immature trematode specimens found in the examined benthic organisms (particularly the families Microphallidae, Troglotrematidae and Nanophyetidae and Euryhelmis zelleri Grabda-Kazubska, 1980, Heterophyidae), and describe cercariae of C. faba. We determined the

  16. The Genus Ixodes (Acari: Ixodidae) in Mexico: Adult Identification Keys, Diagnoses, Hosts, and Distribution (El genero Ixodes (Acari: Ixodidae) en Mexico: claves de identificacion para adultos, diagnosis, huespedes y distribucion)

    DTIC Science & Technology

    2010-01-01

    also from Estado de México (Hoffmann, 1969). Hosts in Mexico. Cricetidae and Hominidae ( Homo sapiens Linnaeus, 1758) (Mammalia) (Hoffmann, 1969...distribution El género Ixodes (Acari: Ixodidae) en México: claves de identifi cación para adultos, diagnosis, huéspedes y distribución Carmen Guzmán...postdoctoral scholarship under the Programa de Formación e Incorporación de Profesores de Carrera en Facultades y Escuelas para el Fortalecimiento de la

  17. Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates South Florida, Ladyfish and Tarpon

    DTIC Science & Technology

    1989-07-01

    Elops saurus England (but uncommon north of Cape Linnaeus (Robins et al. TW T Hatteras) to Rio de Janeiro , Brazil, Preferred common name... lagoons , and coastal habitats (Breder (1966) in the laboratory from Stage 1944; Dahlberg 1972; Gilmore et al. III larvae (18.1-22.7 mm SL; mean, 1981...Biological Report 82P1104)--’ T R EL.82.4. /c0.- July 1989. 0t Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes DT

  18. Whartonia (Fascutonia) natsumei (Acari: Trombiculidae): a new bat chigger collected from Plecotus auritus (Chiroptera: Vespertilionidae) in Japan, with host and distribution records of the genus Whartonia.

    PubMed

    Takahashi, Mamoru; Takahashi, Hisae; Kikuchi, Hirosato

    2006-03-01

    We describe and illustrate a new bat chigger, Whartonia (Fascutonia) natsumei Takahashi, Takahashi & Kikuchi n. sp., ex. Plecotus auritus (Linnaeus, 1758), from Japan, and summarize the host and distribution records of the chiggers of the genus Whartonia Ewing, 1944. With the description of a new species here, the number of Whartonia species increases to 40 composed of 22 species from Asia, 14 from North and South America in addition to Central America, and four from Africa.

  19. Cytogenetic analyses of five amazon lizard species of the subfamilies Teiinae and Tupinambinae and review of karyotyped diversity the family Teiidae.

    PubMed

    Carvalho, Natália Dayane Moura; Arias, Federico José; da Silva, Francijara Araújo; Schneider, Carlos Henrique; Gross, Maria Claudia

    2015-01-01

    Lizards of the family Teiidae (infraorder Scincomorpha) were formerly known as Macroteiidae. There are 13 species of such lizards in the Amazon, in the genera Ameiva (Meyer, 1795), Cnemidophorus (Wagler, 1830), Crocodilurus (Spix, 1825), Dracaena (Daudin, 1801), Kentropyx (Spix, 1825) and Tupinambis (Daudin, 1802). Cytogenetic studies of this group are restricted to karyotype macrostructure. Here we give a compilation of cytogenetic data of the family Teiidae, including classic and molecular cytogenetic analysis of Ameiva ameiva (Linnaeus, 1758), Cnemidophorus sp.1, Kentropyx calcarata (Spix, 1825), Kentropyx pelviceps (Cope, 1868) and Tupinambis teguixin (Linnaeus, 1758) collected in the state of Amazonas, Brazil. Ameiva ameiva, Kentropyx calcarata and Kentropyx pelviceps have 2n=50 chromosomes classified by a gradual series of acrocentric chromosomes. Cnemidophorus sp.1 has 2n=48 chromosomes with 2 biarmed chromosomes, 24 uniarmed chromosomes and 22 microchromosomes. Tupinambis teguixin has 2n=36 chromosomes, including 12 macrochromosomes and 24 microchromosomes. Constitutive heterochromatin was distributed in the centromeric and terminal regions in most chromosomes. The nucleolus organizer region was simple, varying in its position among the species, as evidenced both by AgNO3 impregnation and by hybridization with 18S rDNA probes. The data reveal a karyotype variation with respect to the diploid number, fundamental number and karyotype formula, which reinforces the importance of increasing chromosomal analyses in the Teiidae.

  20. Cytogenetic analyses of five amazon lizard species of the subfamilies Teiinae and Tupinambinae and review of karyotyped diversity the family Teiidae

    PubMed Central

    Carvalho, Natália Dayane Moura; Arias, Federico José; da Silva, Francijara Araújo; Schneider, Carlos Henrique; Gross, Maria Claudia

    2015-01-01

    Abstract Lizards of the family Teiidae (infraorder Scincomorpha) were formerly known as Macroteiidae. There are 13 species of such lizards in the Amazon, in the genera Ameiva (Meyer, 1795), Cnemidophorus (Wagler, 1830), Crocodilurus (Spix, 1825), Dracaena (Daudin, 1801), Kentropyx (Spix, 1825) and Tupinambis (Daudin, 1802). Cytogenetic studies of this group are restricted to karyotype macrostructure. Here we give a compilation of cytogenetic data of the family Teiidae, including classic and molecular cytogenetic analysis of Ameiva ameiva (Linnaeus, 1758), Cnemidophorus sp.1, Kentropyx calcarata (Spix, 1825), Kentropyx pelviceps (Cope, 1868) and Tupinambis teguixin (Linnaeus, 1758) collected in the state of Amazonas, Brazil. Ameiva ameiva, Kentropyx calcarata and Kentropyx pelviceps have 2n=50 chromosomes classified by a gradual series of acrocentric chromosomes. Cnemidophorus sp.1 has 2n=48 chromosomes with 2 biarmed chromosomes, 24 uniarmed chromosomes and 22 microchromosomes. Tupinambis teguixin has 2n=36 chromosomes, including 12 macrochromosomes and 24 microchromosomes. Constitutive heterochromatin was distributed in the centromeric and terminal regions in most chromosomes. The nucleolus organizer region was simple, varying in its position among the species, as evidenced both by AgNO3 impregnation and by hybridization with 18S rDNA probes. The data reveal a karyotype variation with respect to the diploid number, fundamental number and karyotype formula, which reinforces the importance of increasing chromosomal analyses in the Teiidae. PMID:26753079

  1. On merging Acer sections Rubra and Hyptiocarpa: Molecular and morphological evidence.

    PubMed

    Harris, A J; Chen, Yousheng; Olsen, Richard T; Lutz, Sue; Wen, Jun

    2017-01-01

    In this study, we expanded Acer sect. Rubra Pax to include A. sect. Hyptiocarpa Fang. Traditionally, section Rubra comprises two iconic species, Acer rubrum Linnaeus (red maple) and A. saccharinum Linnaeus (silver maple), of eastern North American forests as well as the rare Japanese montane species, A. pycnanthum K. Koch. Section Hyptiocarpa consists of A. laurinum Hasskarl and A. pinnatinervium Merrill, which occur in subtropical and tropical regions of southwestern China to southeast Asia. Here, we confirm prior phylogenetic results showing the close relationship between sects. Rubra and Hyptiocarpa , and we use scanning electron microscopy to demonstrate that leaves of species within these sections have similar arrangements of cuticular waxes, which account for the silvery color of their abaxial surfaces. We describe that the sections also share labile sex expression; inflorescences that range from compound racemose thyrses, to racemes or umbels and that may have undergone evolutionary reduction; and several features of their fruits, such as seed locules without keels, basal portion of wings straight, acute attachment angle between mericarps, and production of some mericarps that are seedless and partially developed at maturity. Our expansion of sect. Rubra to include sect. Hyptiocarpa better elucidates the biogeographic and evolutionary history of these species. Additionally, we show that A. laurinum and A. pinnatinervium have intergrading morphology and are probably synonymous, but we note that further studies are required to conclude their taxonomic status.

  2. A new Heraclides swallowtail (Lepidoptera, Papilionidae) from North America is recognized by the pattern on its neck

    PubMed Central

    Shiraiwa, Kojiro; Cong, Qian; Grishin, Nick V.

    2014-01-01

    Abstract Heraclides rumiko Shiraiwa & Grishin, sp. n. is described from southwestern United States, Mexico, and Central America (type locality: USA, Texas, Duval County). It is closely allied to Heraclides cresphontes (Cramer, 1777) and the two species are sympatric in central Texas. The new species is diagnosed by male genitalia and exhibits a nearly 3% difference from Heraclides cresphontes in the COI DNA barcode sequence of mitochondrial DNA. The two Heraclides species can usually be told apart by the shape and size of yellow spots on the neck, by the wing shape, and the details of wing patterns. “Western Giant Swallowtail” is proposed as the English name for Heraclides rumiko. To stabilize nomenclature, neotype for Papilio cresphontes Cramer, 1777, an eastern United States species, is designated from Brooklyn, New York, USA; and lectotype for Papilio thoas Linnaeus, 1771 is designated from Suriname. We sequenced DNA barcodes and ID tags of nearly 400 Papilionini specimens completing coverage of all Heraclides species. Comparative analyses of DNA barcodes, genitalia, and facies suggest that Heraclides oviedo (Gundlach, 1866), reinstated status, is a species-level taxon rather than a subspecies of Heraclides thoas (Linnaeus, 1771); and Heraclides pallas (G. Gray, [1853]), reinstated status, with its subspecies Heraclides Papilio bajaensis (J. Brown & Faulkner, 1992), comb. n., and Heraclides anchicayaensis Constantino, Le Crom & Salazar, 2002, stat. n., are not conspecific with Heraclides astyalus (Godart, 1819). PMID:25610342

  3. Cranial nerves in the Australian lungfish, Neoceratodus forsteri, and in fossil relatives (Osteichthyes: Dipnoi).

    PubMed

    Kemp, A

    2017-02-01

    Three systems, two sensory and one protective, are present in the skin of the living Australian lungfish, Neoceratodus forsteri, and in fossil lungfish, and the arrangement and innervation of the sense organs is peculiar to lungfish. Peripheral branches of nerves that innervate the sense organs are slender and unprotected, and form before any skeletal structures appear. When the olfactory capsule develops, it traps some of the anterior branches of cranial nerve V, which emerged from the chondrocranium from the lateral sphenotic foramen. Cranial nerve I innervates the olfactory organ enclosed within the olfactory capsule and cranial nerve II innervates the eye. Cranial nerve V innervates the sense organs of the snout and upper lip, and, in conjunction with nerve IX and X, the sense organs of the posterior and lateral head. Cranial nerve VII is primarily a motor nerve, and a single branch innervates sense organs in the mandible. There are no connections between nerves V and VII, although both emerge from the brain close to each other. The third associated system consists of lymphatic vessels covered by an extracellular matrix of collagen, mineralised as tubules in fossils. Innervation of the sensory organs is separate from the lymphatic system and from the tubule system of fossil lungfish. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. The Infrabranchial Musculature and Its Bearing on the Phylogeny of Percomorph Fishes (Osteichthyes: Teleostei)

    PubMed Central

    Datovo, Aléssio; de Pinna, Mário C. C.; Johnson, G. David

    2014-01-01

    The muscles serving the ventral portion of the gill arches ( = infrabranchial musculature) are poorly known in bony fishes. A comparative analysis of the infrabranchial muscles in the major percomorph lineages reveals a large amount of phylogenetically-relevant information. Characters derived from this anatomical system are identified and discussed in light of current hypotheses of phylogenetic relationships among percomorphs. New evidence supports a sister-group relationship between the Batrachoidiformes and Lophiiformes and between the Callionymoidei and Gobiesocoidei. Investigated data also corroborate the existence of two monophyletic groups, one including the Pristolepididae, Badidae, and Nandidae, and a second clade consisting of all non-amarsipid stromateiforms. New synapomorphies are proposed for the Atherinomorphae, Blenniiformes, Lophiiformes, Scombroidei (including Sphyraenidae), and Gobiiformes. Within the latter order, the Rhyacichthyidae and Odontobutidae are supported as the successive sister families of all remaining gobiiforms. The present analysis further confirms the validity of infrabranchial musculature characters previously proposed to support the grouping of the Mugiliformes with the Atherinomorphae and the monophyly of the Labriformes with the possible inclusion of the Pholidichthyiformes. Interestingly, most hypotheses of relationships supported by the infrabranchial musculature have been advanced by preceding anatomists on the basis of distinct data sources, but were never recovered in recent molecular phylogenies. These conflicts clearly indicate the current unsatisfactory resolution of the higher-level phylogeny of percomorphs. PMID:25310286

  5. Comparison of two different dust emission mechanisms over the Horqin Sandy Land area: Aerosols contribution and size distributions

    NASA Astrophysics Data System (ADS)

    Ju, Tingting; Li, Xiaolan; Zhang, Hongsheng; Cai, Xuhui; Song, Yu

    2018-03-01

    Dust aerosols (PM10) emission fluxes due to convective turbulent dust emissions (CTDE) and saltation-bombardment and/or aggregation-disintegration dust emissions (SADE) events were comparatively studied using the data obtained from the Naiman station over the Horqin Sandy Land area in Inner Mongolia, China from 2011 to 2015. The annual cumulative dust fluxes released by CTDE events was about one third of that by SADE events, with the order of 103∼104 μg m-2 s-1. The particle size distributions (PSDs) with diameter between 0.1 and 20 μm during CTDE and SADE events over the Horqin Sandy Land area were simulated based on the fragmentation theory, respectively. The results indicated that an improved equation based on fragmentation theory could be applied to describe the PSDs over the Horqin site which may be because the scale-invariant fragmentation theory mainly explains the PSDs of free dust particles on the surface, which differ from the PSDs of suspend airborne dust and the improved equation was more applicable to the PSDs of SADE events because the dust emission mechanism of SADE are saltation bombardment and aggregation disintegration. The number-related mean aerosol diameters (DN) barely varied under different friction velocity (u*) for SADE events, while the volume-related mean aerosol diameters (DV) changed distinctly with the change of u*. For CTDE events, the DN and DV had no obvious relationship with the change of u* because the dominating influence factor during CTDE event was thermal convection rather than u*. The mass-related PSDs usually exhibited a peak between 0.45 and 0.70 μm during SADE events, while for CTDE events there was a wide peak in the range of 0.10 0.70 μm. The results suggest that DN should be not be recommended as an individual parameter to describe the PSDs. The mass-related PSDs can effectively distinguish the SADE and CTDE events.

  6. Aerodynamic Surface Stress Intermittency and Conditionally Averaged Turbulence Statistics

    NASA Astrophysics Data System (ADS)

    Anderson, W.

    2015-12-01

    Aeolian erosion of dry, flat, semi-arid landscapes is induced (and sustained) by kinetic energy fluxes in the aloft atmospheric surface layer. During saltation -- the mechanism responsible for surface fluxes of dust and sediment -- briefly suspended sediment grains undergo a ballistic trajectory before impacting and `splashing' smaller-diameter (dust) particles vertically. Conceptual models typically indicate that sediment flux, q (via saltation or drift), scales with imposed aerodynamic (basal) stress raised to some exponent, n, where n > 1. Since basal stress (in fully rough, inertia-dominated flows) scales with the incoming velocity squared, u^2, it follows that q ~ u^2n (where u is some relevant component of the above flow field, u(x,t)). Thus, even small (turbulent) deviations of u from its time-averaged value may play an enormously important role in aeolian activity on flat, dry landscapes. The importance of this argument is further augmented given that turbulence in the atmospheric surface layer exhibits maximum Reynolds stresses in the fluid immediately above the landscape. In order to illustrate the importance of surface stress intermittency, we have used conditional averaging predicated on aerodynamic surface stress during large-eddy simulation of atmospheric boundary layer flow over a flat landscape with momentum roughness length appropriate for the Llano Estacado in west Texas (a flat agricultural region that is notorious for dust transport). By using data from a field campaign to measure diurnal variability of aeolian activity and prevailing winds on the Llano Estacado, we have retrieved the threshold friction velocity (which can be used to compute threshold surface stress under the geostrophic balance with the Monin-Obukhov similarity theory). This averaging procedure provides an ensemble-mean visualization of flow structures responsible for erosion `events'. Preliminary evidence indicates that surface stress peaks are associated with the passage of

  7. Spatio-temporal variability of several eco-precipitation indicators in China

    NASA Astrophysics Data System (ADS)

    Guo, B. B.; Zhang, J.; Wang, F.

    2016-12-01

    Climate change is expected to have large impacts on the eco-hydrological processes. Precipitation as one of the most important meteorological factors is a significant parameter in ecohydrology. Many studies and precipitation indexes focused on the long-term precipitation variability have been put forward. However, these former studies did not consider the vegetation response and these indexes could not reflect it efficiently. Eco-precipitation indicators reflecting the features and patterns of precipitations and serving as significant input parameters of eco-hydrological models are of paramount significance to the studies of these models. Therefore we proposed 4 important eco-precipitation indicators—Precipitation Variability Index (PVI), Precipitation Occurrence Rate (λ), Mean Precipitation Depth (1/θ) and Annual Precipitation (AP). The PVI index depicts the precipitation variability with a value of zero for perfectly uniform and increases as precipitation events become more sporadic. The λ, 1/θ and AP depict the precipitation frequency, intensity and annual amount, respectively. With large precipitation and vegetation discrepancies, China is selected as a study area. Firstly, these indicators are calculated separately with 55-years (1961-2015) daily precipitation time-series from 693 weather stations in China. Then, the temporal trend is analyzed through Mann-Kendall (MK) test and parametric t-test in annual time scale. Furthermore, the spatial distribution is analyzed through the spatial interpolation tools ANUsplin. The result shows that: (1) 1/θ increased significantly (4.59cm/10yr) while λ decreased significantly (1.54 days/10yr), which means there is an increasing trend of extreme precipitation events; (2)there is a significant downward trend of PVI, which means the rhythm of precipitation has a uniform and concentrated trend; (3) AP increased insignificantly (0.57mm/10yr); and (4)the MK test of these indicators shows that there is saltation of

  8. [Estimation of the effect derived from wind erosion of soil and dust emission in Tianjin suburbs on the central district based on WEPS model].

    PubMed

    Chen, Li; Han, Ting-Ting; Li, Tao; Ji, Ya-Qin; Bai, Zhi-Peng; Wang, Bin

    2012-07-01

    Due to the lack of a prediction model for current wind erosion in China and the slow development for such models, this study aims to predict the wind erosion of soil and the dust emission and develop a prediction model for wind erosion in Tianjin by investigating the structure, parameter systems and the relationships among the parameter systems of the prediction models for wind erosion in typical areas, using the U.S. wind erosion prediction system (WEPS) as reference. Based on the remote sensing technique and the test data, a parameter system was established for the prediction model of wind erosion and dust emission, and a model was developed that was suitable for the prediction of wind erosion and dust emission in Tianjin. Tianjin was divided into 11 080 blocks with a resolution of 1 x 1 km2, among which 7 778 dust emitting blocks were selected. The parameters of the blocks were localized, including longitude, latitude, elevation and direction, etc.. The database files of blocks were localized, including wind file, climate file, soil file and management file. The weps. run file was edited. Based on Microsoft Visualstudio 2008, secondary development was done using C + + language, and the dust fluxes of 7 778 blocks were estimated, including creep and saltation fluxes, suspension fluxes and PM10 fluxes. Based on the parameters of wind tunnel experiments in Inner Mongolia, the soil measurement data and climate data in suburbs of Tianjin, the wind erosion module, wind erosion fluxes, dust emission release modulus and dust release fluxes were calculated for the four seasons and the whole year in suburbs of Tianjin. In 2009, the total creep and saltation fluxes, suspension fluxes and PM10 fluxes in the suburbs of Tianjin were 2.54 x 10(6) t, 1.25 x 10(7) t and 9.04 x 10(5) t, respectively, among which, the parts pointing to the central district were 5.61 x 10(5) t, 2.89 x 10(6) t and 2.03 x 10(5) t, respectively.

  9. Ventifacts at the Pathfinder landing site

    USGS Publications Warehouse

    Bridges, N.T.; Greeley, R.; Haldemann, A.F.C.; Herkenhoff, K. E.; Kraft, M.; Parker, T.J.; Ward, A.W.

    1999-01-01

    About half of the rocks at the Mars Pathfinder Ares Vallis landing site appear to be ventifacts, rocks abraded by windborne particles. Comparable resolution images taken by the Imager for Mars Pathfinder (IMP) camera and the Viking landers show that ventifacts are more abundant at the Pathfinder site. The ventifacts occur in several forms, including rocks with faceted edges, finger-like projections, elongated pits, flutes, grooves, and possible rills. The trends of elongated pits, flutes, grooves, and rills cluster at ???280-330?? clockwise from north and generally dip 10-30?? away from their trend direction. These orientations are indicative of southeast to northwest winds and differ from the trend of wind tails at the landing site, the direction of local wind streaks, and predictions of the Global Circulation Model, all of which indicate northeast to southwest winds. The disparity between these data sets strongly suggests that local circulation patterns have changed since the abrasion of the ventifacted rocks. The greater number of ventifacts at the Pathfinder site compared to either of the Viking sites is most easily explained as being due to a larger supply of abrading particles, composed of either sand-sized grains or indurated dust aggregates, and higher surface roughness, which should increase the momentum of saltating grains. The Pathfinder ventifacts may have formed shortly after the deposition of outflow channel sediments nearly 2 Gry ago, when a large local supply of abrading particles should have been abundant and atmospheric conditions may have been more conducive to rock abrasion from saltating grains. Based on how ventifacts form on Earth, the several ventifact forms seen at the Pathfinder site and their presence on some rocks but not on others are probably due to local airflow conditions, original rock shape, exposure duration, rock movement, and to a lesser extent, rock lithology. The abundance of ventifacts at the Pathfinder site, together with

  10. The Genus Ixodes (Acari: Ixodidae) in Mexico: Adult Identification Keys, Diagnoses, Hosts, and Distribution

    DTIC Science & Technology

    2010-01-01

    Cricetidae and Hominidae ( Homo sapiens Linnaeus, 1758) (Mammalia) (Hoffmann, 1969). Note. The tick from Valle de Bravo, Estado de México, was...distribution El género Ixodes (Acari: Ixodidae) en México: claves de identifi cación para adultos, diagnosis, huéspedes y distribución Carmen Guzmán...Incorporación de Profesores de Carrera en Facultades y Escuelas para el Fortalecimiento de la Investigación (PROFIP). Tila María Pérez, Curator of CNAC

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

    PubMed

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

    2012-02-01

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

  12. A solar escalator on Mars: Self-lifting of dust layers by radiative heating

    NASA Astrophysics Data System (ADS)

    Daerden, F.; Whiteway, J. A.; Neary, L.; Komguem, L.; Lemmon, M. T.; Heavens, N. G.; Cantor, B. A.; Hébrard, E.; Smith, M. D.

    2015-09-01

    Dust layers detected in the atmosphere of Mars by the light detection and ranging (LIDAR) instrument on the Phoenix Mars mission are explained using an atmospheric general circulation model. The layers were traced back to observed dust storm activity near the edge of the north polar ice cap where simulated surface winds exceeded the threshold for dust lifting by saltation. Heating of the atmospheric dust by solar radiation caused buoyant instability and mixing across the top of the planetary boundary layer (PBL). Differential advection by wind shear created detached dust layers above the PBL that ascended due to radiative heating and arrived at the Phoenix site at heights corresponding to the LIDAR observations. The self-lifting of the dust layers is similar to the "solar escalator" mechanism for aerosol layers in the Earth's stratosphere.

  13. Aeolian Grain Evolution on Mars: Implications for Regolith Origins

    NASA Astrophysics Data System (ADS)

    Sullivan, R. J.; Cabrol, N. A.; Golombek, M.; Herkenhoff, K. E.; Landis, G.; Mer Athena Science Team

    2010-12-01

    Early wind tunnel experiments and the Viking Lander experience led to concepts of grain evolution and regolith development on Mars. Wind tunnel experiments showed that 100-150 μm grains are easiest to entrain on Mars, but at 10 times higher wind speeds than on Earth. Even if trajectory speeds of martian saltating grains achieve smaller fractions of entraining wind speeds than on Earth, kinetic energies of these grains would be much higher, with greater potential for damage to the grains during return collisions with the particle bed. On this basis Sagan et al. [1977] JGR 82, 28, 4430 proposed that aeolian grain evolution on Mars followed a “kamikaze” pattern in which an initially coarse grain, entrained only relatively rarely by the strongest winds, would be abraded by high kinetic energy impacts and migrate through successively smaller size-frequencies at an ever-increasing rate (as entrainment became easier and thus more likely) until the grain was essentially turned to dust. On this basis it was proposed that sand-sized grains might be relatively short-lived and perhaps rare on Mars. MER observations motivate adjustments to these concepts, with implications for origins of martian regolith reworked by wind. Along both MER traverses, on opposite sides of the planet, regolith is volumetrically dominated by very fine sand mixed with unresolved finer grains. Sorting probably is poor, based on weakly cohesive remolding by rover wheel cleats. The size-frequency of this material, even if not precisely known, is consistent with grains that have evolved by attrition to sizes smaller than the most easily-moved 100-150 μm interval, to where entrainment becomes more difficult due to the increasing relative importance of inter-particle surface forces. At these smaller sizes also, kinetic energies have been reduced proportionally by the cube of the particle radius, so grain-to-grain attrition is less effective for further evolution to even smaller grain sizes

  14. Pseudascarophis brasiliensis sp. nov. (Nematoda: Cystidicolidae) parasitic in the Bermuda chub Kyphosus sectatrix (Perciformes: Kyphosidae) from southeastern Brazil.

    PubMed

    Pereira, Felipe Bisaggio; Pereira, Aldenice de Nazaré; Timi, Juan Tomás; Luque, José Luis

    2013-06-01

    A new species of Pseudascarophis (Nematoda: Cystidicolidae) found in the stomach of Kyphosus sectatrix (Linnaeus) (Kyphosidae), off Rio de Janeiro, Brazil, is described. The new species can be differentiated from the other congeners by the presence of lateral alae, distinct but inconspicuous cephalic papillae at the anterior end, three pairs of precloacal and one pair of adcloacal papillae in males, egg morphology and morphometry of glandular oesophagus and spicules. Pseudascarophis tropica is transferred to Ascarophis as Ascarophis tropica (Solov'eva) comb. n. due to its ambiguous diagnosis.

  15. Late Pleistocene voles (Arvicolinae, Rodentia) from the Baranica Cave (Serbia)

    NASA Astrophysics Data System (ADS)

    Bogićević, Katarina; Nenadić, Draženko; Mihailović, Dušan

    2012-02-01

    Baranica is a cave system situated in the south-eastern part of Serbia, four kilometers south to Knjaževac, on the right bank of the Trgovi\\vski Timok. The investigations in Baranica were conducted from 1994 to 1997 by the Faculty of Philosophy from Belgrade and the National Museum of Knjaževac. Four geological layers of Quaternary age were recovered. The abundance of remains of both large and small mammals was noticed in the early phase of the research. In this paper, the remains of eight vole species are described: Arvicola terrestris (Linnaeus, 1758), Chionomys nivalis (Martins, 1842), Microtus (Microtus) arvalis (Pallas, 1778) and Microtus (Microtus) agrestis (Linnaeus, 1761), Microtus (Stenocranius) gregalis (Pallas, 1779), Microtus (Terricola) subterraneus (de Sélys-Longchamps, 1836), Clethrionomys glareolus (Schreber, 1780) and Lagurus lagurus (Pallas, 1773). Among them, steppe and open area inhabitants prevail. Based on the evolutionary level and dimensions of the Arvicola terrestris molars, as well as the overall characteristics of the fauna, it was concluded that the deposits were formed in the last glacial period of the Late Pleistocene. These conclusions are rather consistent with the absolute dating of large mammal bones (23.520 ± 110 B.P. for Layer 2 and 35.780 ± 320 B.P. for Layer 4).

  16. To attach or not to attach? The effect of carrier surface morphology and topography on attachment of phoretic deutonymphs of Uropoda orbicularis (Acari).

    PubMed

    Bajerlein, Daria; Adamski, Zbigniew; Kacalak, Wojciech; Tandecka, Katarzyna; Wiesner, Maciej; Jurga, Stefan

    2016-08-01

    Previous studies on preferences of phoretic deutonymphs of Uropodina for attachment sites have shown that they frequently select smooth and hydrophobic surfaces. The aim of our study was to provide the detailed morphological and topographical characteristics of beetle body surfaces to which deutonymphs frequently attach and to verify how the presence of setae and surface sculpture affects deutonymph attachment. The study was conducted on Uropoda orbicularis (Müller, 1776) and its common beetle carriers: Aphodius prodromus (Brahm, 1790), Aphodius fimetarius (Linnaeus, 1758), Onthophagus nuchicornis (Linnaeus, 1758) and Margarinotus carbonarius (Hoffmann, 1803). Morphology and topography of elytra, femora, propygidia and pygidia of beetles were analysed mainly using SEM methods supported with CLSM and AFM techniques. The hypothesis that deutonymphs may attach to surfaces covered with setae, if seta density is low enough not to disturb mite movement, was tested. The study revealed that deutonymphs attach to surfaces of various types as follows: (i) smooth, (ii) hairy, i.e., covered with setae, (iii) flat and (iv) sculptured. Smooth body parts and body parts covered with setae of low density were most frequently and intensively occupied with deutonymphs. Surfaces of high seta density were avoided by mites. Within elytra of Aphodius beetles, deutonymphs definitely preferred flat surfaces of elytral intervals. On the contrary, densely punctuated propygidium and pygidium in M. carbonarius were heavily infested with deutonymphs. We conclude that carrier surface morphology and topography are important for Uropodina deutonymph attachment, but these two factors cannot fully explain the observed relation.

  17. Population Structure, Movement Patterns, and Frequency of Multiple Matings in Tenodera sinensis (Mantodea: Mantidae).

    PubMed

    Christensen, Tyler; Brown, William D

    2018-04-14

    Models of the evolution of sexual cannibalism show that the frequency of male mating opportunities has significant impact on male choice and male risk aversion. In this study, we examined ecological components that should affect opportunities for multiple mating in wild populations of the Chinese mantid (Tenodera sinensis Saussure). While conducting mark-recapture studies of two field populations over the course of two seasons, along with Global Positioning System data on locations of individuals, we collected data on population densities, movement patterns, and individual ranges to estimate the overlap of adult males and female mantids. Our results show that local populations of mantids range from 89 to 161 individuals and occur at densities ranging from 10 to 39 mantids per 1,000 m2. Males move greater distances daily compared with females, giving males larger home range sizes. The ranges of male mantids overlapped with multiple females, thus offering the potential for multiple mating by males. We directly observed 11 encounters between male and female T. sinensis, including one multiple mating by an individual male. The overall mate encounter rate for males was 12.5%. We also provide additional observations of interspecific sexual attraction between T. sinensis and Mantis religiosa Linne (Mantodea: Mantidae). Mantids were most commonly found within the top 20% of two flowering plants, goldenrod (Solidago Linnaeus spp. (Asterales: Asteraceae)) and mugwort (Artemisia vulgaris Linnaeus (Asterales: Asteraceae)), which should place them in prime locations for capturing flying pollinators.

  18. To attach or not to attach? The effect of carrier surface morphology and topography on attachment of phoretic deutonymphs of Uropoda orbicularis (Acari)

    NASA Astrophysics Data System (ADS)

    Bajerlein, Daria; Adamski, Zbigniew; Kacalak, Wojciech; Tandecka, Katarzyna; Wiesner, Maciej; Jurga, Stefan

    2016-08-01

    Previous studies on preferences of phoretic deutonymphs of Uropodina for attachment sites have shown that they frequently select smooth and hydrophobic surfaces. The aim of our study was to provide the detailed morphological and topographical characteristics of beetle body surfaces to which deutonymphs frequently attach and to verify how the presence of setae and surface sculpture affects deutonymph attachment. The study was conducted on Uropoda orbicularis (Müller, 1776) and its common beetle carriers: Aphodius prodromus (Brahm, 1790), Aphodius fimetarius (Linnaeus, 1758), Onthophagus nuchicornis (Linnaeus, 1758) and Margarinotus carbonarius (Hoffmann, 1803). Morphology and topography of elytra, femora, propygidia and pygidia of beetles were analysed mainly using SEM methods supported with CLSM and AFM techniques. The hypothesis that deutonymphs may attach to surfaces covered with setae, if seta density is low enough not to disturb mite movement, was tested. The study revealed that deutonymphs attach to surfaces of various types as follows: (i) smooth, (ii) hairy, i.e., covered with setae, (iii) flat and (iv) sculptured. Smooth body parts and body parts covered with setae of low density were most frequently and intensively occupied with deutonymphs. Surfaces of high seta density were avoided by mites. Within elytra of Aphodius beetles, deutonymphs definitely preferred flat surfaces of elytral intervals. On the contrary, densely punctuated propygidium and pygidium in M. carbonarius were heavily infested with deutonymphs. We conclude that carrier surface morphology and topography are important for Uropodina deutonymph attachment, but these two factors cannot fully explain the observed relation.

  19. Pb and Cd bioaccumulations in the habitat and preys of red-crowned cranes (Grus japonensis) in Zhalong Wetland, Northeastern China.

    PubMed

    Luo, Jinming; Yin, Xiongrui; Ya, Yajie; Wang, Yongjie; Zang, Shuying; Zhou, Xia

    2013-12-01

    Pb and Cd concentrations in the habitat and preys of the red-crowned crane (i.e., reed rhizomes and three typical aquatic animal families (Perccottus glehni Dybowski, Carassius auratus Linnaeus, and Viviparidae)) were analyzed to examine the impact of these hazards on red-crowned cranes in northeastern China. Results indicated that Pb and Cd concentrations in the preys of the red-crowned cranes were elevated via food chain. Most of the detected Pb and Cd contents in the sediments were above the natural background level, ranging from 9.85 to 129.72 ppm and 1.23 to 10.63 ppm (dry weight), respectively. Cd geo-accumulation index at all sites were larger than 3, even reached 5.22, suggesting serious pollution in this region. Three common water animal families were detected to contain heavy metals, following the order of increasing concentrations: primary consumers (i.e., Viviparidae and Carassius auratus Linnaeus) < secondary consumers (i.e., Perccottus glehni Dybowski). Pb and Cd concentrations in the buffer zone are significantly higher than in the core area and being elevated in the food chain. The molten feathers of the red-crowned cranes showed the highest toxic metal concentrations of Pb (2.09 to 5.81 ppm) and Cd (1.42 to 3.06 ppm) compared with the feces produced by cranes and residual eggshell left by water fowls. Exceptionally high Pb and Cd concentrations in the cranes and their preys were thought to be associated with their habitat.

  20. Are Ascaris lumbricoides and Ascaris suum a single species?

    PubMed Central

    2012-01-01

    Since the original description and naming of Ascaris lumbricoides from humans by Linnaeus in 1758 and later of Ascaris suum from pigs by Goeze 1782, these species have been considered to be valid. Four hypotheses relative to the conspecificity or lack thereof (and thus origin of these species) are possible: 1) Ascaris lumbricoides (usually infecting humans) and Ascaris suum (recorded mostly from pigs) are both valid species, with the two species originating via a speciation event from a common ancestor sometime before the domestication of pigs by humans, or 2) Ascaris lumbricoides in humans is derived directly from the species A. suum found in pigs with A. suum then existing as a persistent ancestor after formation of A. lumbricoides, or 3) Ascaris suum is derived directly from A. lumbricoides with the persistent ancestor being A. lumbricoides and A. suum being the newly derived species, and finally, 4) Ascaris lumbricoides and A. suum are the same species, this hypothesis being supported by studies showing both low morphological and low genetic divergence at several genes. We present and discuss paleoparasitological and genetic evidence that complement new data to evaluate the origin and evolution of Ascaris spp. in humans and pigs, and the uniqueness of the species in both hosts. Finally, we conclude that Ascaris lumbricoides and A. suum are a single species and that the name A. lumbricoides Linnaeus 1758 has taxonomic priority; therefore A. suum Goeze 1782 should be considered a synonym of A. lumbricoides. PMID:22348306

  1. Encystment of parasitic freshwater pearl mussel (Margaritifera margaritifera) larvae coincides with increased metabolic rate and haematocrit in juvenile brown trout (Salmo trutta).

    PubMed

    Filipsson, Karl; Brijs, Jeroen; Näslund, Joacim; Wengström, Niklas; Adamsson, Marie; Závorka, Libor; Österling, E Martin; Höjesjö, Johan

    2017-04-01

    Gill parasites on fish are likely to negatively influence their host by inhibiting respiration, oxygen transport capacity and overall fitness. The glochidia larvae of the endangered freshwater pearl mussel (FPM, Margaritifera margaritifera (Linnaeus, 1758)) are obligate parasites on the gills of juvenile salmonid fish. We investigated the effects of FPM glochidia encystment on the metabolism and haematology of brown trout (Salmo trutta Linnaeus, 1758). Specifically, we measured whole-animal oxygen uptake rates at rest and following an exhaustive exercise protocol using intermittent flow-through respirometry, as well as haematocrit, in infested and uninfested trout. Glochidia encystment significantly affected whole-animal metabolic rate, as infested trout exhibited higher standard and maximum metabolic rates. Furthermore, glochidia-infested trout also had elevated levels of haematocrit. The combination of an increased metabolism and haematocrit in infested fish indicates that glochidia encystment has a physiological effect on the trout, perhaps as a compensatory response to the potential respiratory stress caused by the glochidia. When relating glochidia load to metabolism and haematocrit, fish with low numbers of encysted glochidia were the ones with particularly elevated metabolism and haematocrit. Standard metabolic rate decreased with substantial glochidia loads towards levels similar to those of uninfested fish. This suggests that initial effects visible at low levels of encystment may be countered by additional physiological effects at high loads, e.g. potential changes in energy utilization, and also that high numbers of glochidia may restrict oxygen uptake by the gills.

  2. On merging Acer sections Rubra and Hyptiocarpa: Molecular and morphological evidence

    PubMed Central

    Harris, AJ; Chen, Yousheng; Olsen, Richard T.; Lutz, Sue; Wen, Jun

    2017-01-01

    Abstract In this study, we expanded Acer sect. Rubra Pax to include A. sect. Hyptiocarpa Fang. Traditionally, section Rubra comprises two iconic species, Acer rubrum Linnaeus (red maple) and A. saccharinum Linnaeus (silver maple), of eastern North American forests as well as the rare Japanese montane species, A. pycnanthum K. Koch. Section Hyptiocarpa consists of A. laurinum Hasskarl and A. pinnatinervium Merrill, which occur in subtropical and tropical regions of southwestern China to southeast Asia. Here, we confirm prior phylogenetic results showing the close relationship between sects. Rubra and Hyptiocarpa, and we use scanning electron microscopy to demonstrate that leaves of species within these sections have similar arrangements of cuticular waxes, which account for the silvery color of their abaxial surfaces. We describe that the sections also share labile sex expression; inflorescences that range from compound racemose thyrses, to racemes or umbels and that may have undergone evolutionary reduction; and several features of their fruits, such as seed locules without keels, basal portion of wings straight, acute attachment angle between mericarps, and production of some mericarps that are seedless and partially developed at maturity. Our expansion of sect. Rubra to include sect. Hyptiocarpa better elucidates the biogeographic and evolutionary history of these species. Additionally, we show that A. laurinum and A. pinnatinervium have intergrading morphology and are probably synonymous, but we note that further studies are required to conclude their taxonomic status. PMID:29033667

  3. Comparison of elemental composition in two wild and cultured marine fish and potential risks to human health.

    PubMed

    Marengo, Michel; Durieux, Eric D H; Ternengo, Sonia; Lejeune, Pierre; Degrange, Elise; Pasqualini, Vanina; Gobert, Sylvie

    2018-08-30

    Among all available species, fish are a powerful model for risk-benefit assessments to study the effects of contaminants on human health. Gilthead seabream (Sparus aurata, Linnaeus 1758) and european seabass (Dicentrarchus labrax, Linnaeus 1758) are two species of great economic importance, representing very large production volumes in the Mediterranean. The objective of this study is (1) to analyze the concentrations of Trace Elements (TE) between wild and cultured seabream and seabass specimens, (2) to compare the determined concentrations with other studies, and (3) to increase the data about the potential risks to human health. Our results point to significant intra- and interspecies-specific differences between wild and cultured fish for several trace elements. Several strong and moderate inter-elemental correlations in fish muscle were observed through correlation analysis. In our study, the mean levels of trace elements were still below the standard safety values for fish intended for human consumption. The same results were reached for all the parameters analyzed (international legal limits, estimated weekly intake, provisional tolerable weekly intake, target hazard quotient, target cancer risk), with trace element levels in fish below those that could pose a risk to human health. Consequently, these fish can be considered safe for human consumption. A better understanding of the levels of trace elements in fish would also better inform consumers about the potential risks of exposure to contaminants. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Out of the South? The first Afrotropical record of Prochyliza Walker (Diptera: Piophilidae), with description of a new species.

    PubMed

    Martín-Vega, Daniel; Ebejer, Martin J; Whitmore, Daniel

    2017-02-15

    The genus Prochyliza Walker is recorded for the first time from the Afrotropical Region. A new species, Prochyliza ignifera sp. nov., is described from the Indian Ocean islands of Aldabra and La Réunion. The status of this species as possibly the most primitive in the genus Prochyliza is hypothesised and discussed, raising some questions about the taxonomy and the zoogeographical origin of the group. The holotype of Piophila viridicollis Macquart from La Réunion was studied and it is instated as a subjective junior synonym of Piophila casei (Linnaeus), syn. nov.

  5. Cucullanus pargi sp. n. (Nematoda: Cucullanidae) from the grey snapper Lutjanus griseus off the southern coast of Quintana Roo, Mexico.

    PubMed

    González-Solís, David; Tuz-Paredes, Vielka M; Quintal-Loria, Miguel A

    2007-09-01

    A new nematode species, Cucullanus pargi sp. n., is described from the intestine and pyloric caeca of the grey snapper, Lutjanus griseus (Linnaeus), off the southern Quintana Roo coast, Mexico. This species shows similar morphological features as cucullanids occurring in marine and brackish-water fishes; however, it differs from all other species in the length of spicules, arrangement and number of caudal papillae, position of the excretory pore and deirids. Cucullanus pargi is the third species of this genus described from fishes in Mexico and the second one from Mexican marine fishes.

  6. First checklist of the fruit flies of Morocco, including new records (Diptera, Tephritidae)

    PubMed Central

    Harym, Younes El; Belqat, Boutaïna

    2017-01-01

    Abstract The first checklist of the Tephritidae of Morocco, containing 59 species, is presented here. Out of 38 species collected during the present project, three (Campiglossa martii (Becker, 1908), Tephritis divisa (Rondani, 1871), and Terellia sp. near longicauda) present new records for North Africa, and ten (Carpomya incompleta (Becker, 1903), Chaetorellia conjuncta (Becker, 1913), Chetostoma curvinerve Rondani, 1856, Dacus frontalis (Becker, 1922), D. longistylus (Wiedemann, 1830), Dioxyna sororcula (Wiedemann, 1830), Ensina sonchi (Linnaeus, 1767), Myopites inulaedyssentericae Blot, 1827, M. stylatus Fabricius, 1794, and Tephritis vespertina (Loew, 1844)) are new for Morocco. PMID:29118602

  7. Pseudascarophis brasiliensis sp. nov. (Nematoda: Cystidicolidae) parasitic in the Bermuda chub Kyphosus sectatrix (Perciformes: Kyphosidae) from southeastern Brazil

    PubMed Central

    Pereira, Felipe Bisaggio; Pereira, Aldenice de Nazaré; Timi, Juan Tomás; Luque, José Luis

    2013-01-01

    A new species of Pseudascarophis (Nematoda: Cystidicolidae) found in the stomach of Kyphosus sectatrix (Linnaeus) (Kyphosidae), off Rio de Janeiro, Brazil, is described. The new species can be differentiated from the other congeners by the presence of lateral alae, distinct but inconspicuous cephalic papillae at the anterior end, three pairs of precloacal and one pair of adcloacal papillae in males, egg morphology and morphometry of glandular oesophagus and spicules. Pseudascarophis tropica is transferred to Ascarophis as Ascarophis tropica (Solov'eva) comb. n. due to its ambiguous diagnosis. PMID:23828003

  8. Aeolian Sand Transport in the Planetary Context: Respective Roles of Aerodynamic and Bed-Dilatancy Thresholds

    NASA Technical Reports Server (NTRS)

    Marshall, J. R.; Borucki, J.; Bratton, C.

    1999-01-01

    The traditional view of aeolian sand transport generally estimates flux from the perspective of aerodynamic forces creating the airborne grain population, although it has been recognized that "reptation" causes a significant part of the total airborne flux; reptation involves both ballistic injection of grains into the air stream by the impact of saltating grains as well as the "nudging" of surface grains into a creeping motion. Whilst aerodynamic forces may initiate sand motion, it is proposed here that within a fully-matured grain cloud, flux is actually governed by two thresholds: an aerodynamic threshold, and a bed-dilatancy threshold. It is the latter which controls the reptation population, and its significance increases proportionally with transport energy. Because we only have experience with terrestrial sand transport, extrapolations of aeolian theory to Mars and Venus have adjusted only the aerodynamic factor, taking gravitational forces and atmospheric density as the prime variables in the aerodynamic equations, but neglecting reptation. The basis for our perspective on the importance of reptation and bed dilatancy is a set of experiments that were designed to simulate sand transport across the surface of a martian dune. Using a modified sporting crossbow in which a sand-impelling sabot replaced the bolt-firing mechanism, individual grains of sand were fired at loose sand targets with glancing angles typical of saltation impact; grains were projected at about 80 m/s to simulate velocities commensurate with those predicted for extreme martian aeolian conditions. The sabot impelling method permitted study of individual impacts without the masking effect of bed mobilization encountered in wind-tunnel studies. At these martian impact velocities, grains produced small craters formed by the ejection of several hundred grains from the bed. Unexpectedly, the craters were not elongated, despite glancing impact; the craters were very close to circular in planform

  9. Aeolian Sand Transport in the Planetary Context: Respective Roles of Aerodynamic and Bed-Dilatancy Thresholds

    NASA Astrophysics Data System (ADS)

    Marshall, J. R.; Borucki, J.; Bratton, C.

    1999-09-01

    The traditional view of aeolian sand transport generally estimates flux from the perspective of aerodynamic forces creating the airborne grain population, although it has been recognized that "reptation" causes a significant part of the total airborne flux; reptation involves both ballistic injection of grains into the air stream by the impact of saltating grains as well as the "nudging" of surface grains into a creeping motion. Whilst aerodynamic forces may initiate sand motion, it is proposed here that within a fully-matured grain cloud, flux is actually governed by two thresholds: an aerodynamic threshold, and a bed-dilatancy threshold. It is the latter which controls the reptation population, and its significance increases proportionally with transport energy. Because we only have experience with terrestrial sand transport, extrapolations of aeolian theory to Mars and Venus have adjusted only the aerodynamic factor, taking gravitational forces and atmospheric density as the prime variables in the aerodynamic equations, but neglecting reptation. The basis for our perspective on the importance of reptation and bed dilatancy is a set of experiments that were designed to simulate sand transport across the surface of a martian dune. Using a modified sporting crossbow in which a sand-impelling sabot replaced the bolt-firing mechanism, individual grains of sand were fired at loose sand targets with glancing angles typical of saltation impact; grains were projected at about 80 m/s to simulate velocities commensurate with those predicted for extreme martian aeolian conditions. The sabot impelling method permitted study of individual impacts without the masking effect of bed mobilization encountered in wind-tunnel studies. At these martian impact velocities, grains produced small craters formed by the ejection of several hundred grains from the bed. Unexpectedly, the craters were not elongated, despite glancing impact; the craters were very close to circular in planform

  10. Feeding ecology of Gila boraxobius (Osteichthyes: Cyprindae) endemic to a thermal lake in southeastern Oregon

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

    Williams, J.E.; Williams, C.D.

    1980-06-30

    Gila boraxobius is a dwarf species of cyprinid endemic to a thermal lake in southeastern Oregon. Despite a relatively depauperate fauna and flora in the lake, 24 food items were found in intestines of G. boraxobius. Ten of the 24 foods, including six insects, were of terrestrial origin. The relative importance of food items fluctuated seasonally. Diatoms, chironomid larvae, microcrustaceans, and dipteran adults were the primary foods during spring. In summer, diatoms decreased and terrestrial insects increased in importance. During autumn important foods were terrestrial insects, chironomid larvae, and diatoms. Diatoms and microcrustaceans increased in importance during winter. Chironomid larvaemore » were of importance in winter, when the importance of terrestrial food items decreased substantially. Similar food habits were observed between juveniles and adults, except that adults consumed more gastropods and diatoms and juveniles consumed more copepods and terrestrial insects. Gila boraxobius feeds opportunistically with individuals commonly containing mostly one food item. Fish typically feed by picking foods from soft bottom sediments or from rocks. However, fish will feed throughout the water column or on the surface if food is abundant there. Gila boraxobius feeds throughout the day, with a peak in feeding activity just after sunset. A daily ration of 11.1 percent body weight was calculated for the species during June. A comparison of food habits among G. boraxobius and populations of G. alvordensis during the summer shows that all are opportunistic in feeding, but that G. boraxobius relies more heavily on terrestrial foods.« less

  11. The Jaw Adductor Muscle Complex in Teleostean Fishes: Evolution, Homologies and Revised Nomenclature (Osteichthyes: Actinopterygii)

    PubMed Central

    Datovo, Aléssio; Vari, Richard P.

    2013-01-01

    The infraclass Teleostei is a highly diversified group of bony fishes that encompasses 96% of all species of living fishes and almost half of extant vertebrates. Evolution of various morphological complexes in teleosts, particularly those involving soft anatomy, remains poorly understood. Notable among these problematic complexes is the adductor mandibulae, the muscle that provides the primary force for jaw adduction and mouth closure and whose architecture varies from a simple arrangement of two segments to an intricate complex of up to ten discrete subdivisions. The present study analyzed multiple morphological attributes of the adductor mandibulae in representatives of 53 of the 55 extant teleostean orders, as well as significant information from the literature in order to elucidate the homologies of the main subdivisions of this muscle. The traditional alphanumeric terminology applied to the four main divisions of the adductor mandibulae – A1, A2, A3, and Aω – patently fails to reflect homologous components of that muscle across the expanse of the Teleostei. Some features traditionally used as landmarks for identification of some divisions of the adductor mandibulae proved highly variable across the Teleostei; notably the insertion on the maxilla and the position of muscle components relative to the path of the ramus mandibularis trigeminus nerve. The evolutionary model of gain and loss of sections of the adductor mandibulae most commonly adopted under the alphanumeric system additionally proved ontogenetically incongruent and less parsimonious than a model of subdivision and coalescence of facial muscle sections. Results of the analysis demonstrate the impossibility of adapting the alphanumeric terminology so as to reflect homologous entities across the spectrum of teleosts. A new nomenclatural scheme is proposed in order to achieve congruence between homology and nomenclature of the adductor mandibulae components across the entire Teleostei. PMID:23565279

  12. New Curculionoidea (Coleoptera) records for Canada

    PubMed Central

    Douglas, Hume; Bouchard, Patrice; Anderson, Robert S.; de Tonnancour, Pierre; Vigneault, Robert; Webster, Reginald P.

    2013-01-01

    Abstract The following species of Curculionoidea are recorded from Canada for the first time, in ten cases also representing new records at the generic level: Ischnopterapion (Ischnopterapion) loti (Kirby, 1808); Stenopterapion meliloti (Kirby, 1808) (both Brentidae); Atrichonotus taeniatulus (Berg, 1881); Barinus cribricollis (LeConte, 1876); Caulophilus dubius (Horn, 1873); Cionus scrophulariae (Linnaeus, 1758); Cryptorhynchus tristis LeConte, 1876; Cylindrocopturus furnissi Buchanan, 1940; Cylindrocopturus quercus (Say, 1832); Desmoglyptus crenatus (LeConte, 1876); Pnigodes setosus LeConte, 1876; Pseudopentarthrum parvicollis (Casey, 1892); Sibariops confinis (LeConte, 1876); Sibariops confusus (Boheman, 1836); Smicronyx griseus LeConte, 1876; Smicronyx lineolatus Casey, 1892; Euwallacea validus (Eichhoff, 1875); Hylocurus rudis (LeConte, 1876); Lymantor alaskanus Wood, 1978; Phloeotribus scabricollis (Hopkins, 1916); Scolytus oregoni Blackman, 1934; Xyleborus celsus Eichhoff, 1868; Xyleborus ferrugineus (Fabricius, 1801); Xylosandrus crassiusculus (Motschulsky, 1866) (all Curculionidae). In addition the following species were recorded for the first time from these provinces and territories: Yukon – Dendroctonus simplex LeConte, 1868; Phloetribus piceae Swaine, 1911 (both Curculionidae); Northwest Territories – Loborhynchapion cyanitinctum (Fall, 1927) (Brentidae); Nunavut – Dendroctonus simplex LeConte, 1868 (Curculionidae); Alberta – Anthonomus tectus LeConte, 1876; Promecotarsus densus Casey, 1892; Dendroctonus ponderosae Hopkins, 1902; Hylastes macer LeConte, 1868; Rhyncolus knowltoni (Thatcher, 1940); Scolytus schevyrewi Semenov Tjan-Shansky, 1902 (all Curculionidae); Saskatchewan – Phloeotribus liminaris (Harris, 1852); Rhyncolus knowltoni (Thatcher, 1940); Scolytus schevyrewi Semenov Tjan-Shansky, 1902 (all Curculionidae); Manitoba – Cosmobaris scolopacea Germar, 1819; Listronotus maculicollis (Kirby, 1837); Listronotus punctiger LeConte, 1876

  13. Ultrastructure of spermatozoa in cobia, Rachycentron canadum (Linnaeus, 1766).

    PubMed

    Dhanasekar, Krishnamoorthy; Selvakumar, Narasimman; Munuswamy, Natesan

    2018-02-01

    Ultrastructure and development of spermatozoa in cobia, Rachycentron canadum are described. Sections through the testis show different developmental stages viz, Spermatocytes, spermatids and sperm. Spermatozoa of R. canadum exhibit the configuration of uniflagellated, anacrosomal Type I aquasperm, typical for externally fertilizing fish. Mature spermatozoon is seen with a prominent head and long cylindrical flagellum. Ultrastructure of sperm shows invaginated 'U' shaped nucleus and other organelles. The mitochondrial matrix is electron-dense with irregular arrangement of the cristae. The nucleus reveals a deep invagination (nuclear fossa) in which the centriolar complex is located. The centriolar complex lies inside the nuclear fossa and is composed of a proximal and a distal centriole. The two centrioles are placed perpendicular to each other. The flagellum has a typical eukaryotic organization (microtubule doublets 9 + 2 pattern) and measures around 36.21 ± 0.42 μm in length. This study for the first time provides a comprehensive detail on the ultrastructure and developmental process of sperm in cobia, R. canadum. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Dietary protein requirement of juvenile turbot ( Scophthalmus maximus Linnaeus)

    NASA Astrophysics Data System (ADS)

    Liu, Xingwang; Mai, Kangsen; Liufu, Zhiguo; Ai, Qinghui

    2015-04-01

    The dietary protein requirement of juvenile turbot (initial average weight, 38.2 g ± 0.1 g) reared indoor in aerated aquaria was determined in this study. Five energy equal experimental diets were formulated with fish meal as protein source, which contained different concentrations of protein (47.2%, 51.0%, 54.6%, 59.3% and 63.6% of dry diet). Three groups of fish with 18 individuals in each, were cultured in 300-L tanks and fed twice a day for 8 weeks. During culture, temperature was controlled between 15.0 and 18.0°C, salinity was controlled between 28.5 and 32.0, acidity was controlled between pH7.8 and pH8.5, and ammonia nitrogen was maintained below 0.03 mg L-1 and dissolved oxygen was maintained about 7 mg L-1. Results showed that the growth of fish was significantly affected by dietary protein content ( P < 0.05). Specific growth rate ( SGR) of turbot increased when dietary protein content varied between 47.2% and 51.0% ( P < 0.05), and then kept stable when dietary protein content was higher than 51.0%. Fish which were fed the diet containing 63.6% protein showed the highest SGR while those fed the diet containing 59.3% protein showed the highest feed efficiency rate. No significant difference of feed intake and protein efficiency ratio was found among experimental diets ( P > 0.05). Broken-line regression analysis of SGR showed that the optimal dietary protein requirement of turbot was about 57.0%.

  15. Evidence for an autumn downstream migration of Atlantic salmon Salmo salar (Linnaeus) and brown trout Salmo trutta (Linnaeus) parr to the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Taal, Imre; Kesler, Martin; Saks, Lauri; Rohtla, Mehis; Verliin, Aare; Svirgsden, Roland; Jürgens, Kristiina; Vetemaa, Markus; Saat, Toomas

    2014-06-01

    In the eastern Baltic rivers, anadromous salmonid parr are known to smoltify and migrate to the sea from March until June, depending on latitude, climate and hydrological conditions. In this study, we present the first records of autumn descent of brown trout Salmo trutta and Atlantic salmon Salmo salar from the Baltic Sea Basin. Otolith microchemistry analyses revealed that these individuals hatched in freshwater and had migrated to the brackish water shortly prior to capture. The fish were collected in 2006, 2008, 2009 and 2013 from Eru Bay (surface salinity 4.5-6.5 ‰), Gulf of Finland. This relatively wide temporal range of observations indicates that the autumn descent of anadromous salmonids is not a random event. These results imply that autumn descent needs more consideration in the context of the effective stock management, assessment and restoration of Baltic salmonid populations and their habitats.

  16. [HELMINTHS OF THE COMMON ROACH (RUTILUS RUTILUS LINNAEUS, 1758) AND THE EUROPEAN PERCH (PERCA FLUVIALITIS LINNAEUS, 1758) IN THE LAKE TERKHIIN TSAGAAN (MONGOLIA)].

    PubMed

    Lebedeva, D I; Mendsaikhan, B; Chantuu, Kh; Jargalmaa, G

    2015-01-01

    The article provides data about helminthes of the common roach and the European perch in the Lake Terkhiin Tsagaan (Mongolia). Six parasite species were found. Data on the occurrence of the trematode species and larvae of Streptocara crassicauda are obtained for the first time. Species composition of Diplostomum spp. metacercariae parasitizing in fish eyes is updated.

  17. Evolution of cholinesterases in the animal kingdom.

    PubMed

    Pezzementi, Leo; Chatonnet, Arnaud

    2010-09-06

    Cholinesterases emerged from a family of enzymes and proteins with adhesion properties. This family is absent in plants and expanded in multicellular animals. True cholinesterases appeared in triploblastic animals together with the cholinergic system. Lineage specific duplications resulted in two acetylcholinesterases in most hexapods and in up to four genes in nematodes. In vertebrates the duplication leading to acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) is now considered to be an ancient event which occurred before the split of osteichthyes. The product of one or the other of the paralogues is responsible for the physiological hydrolysis of acetylcholine, depending on the species lineage and tissue considered. The BChE gene seems to have been lost in some fish lineages. The complete genome of amphioxus (Branchiostoma floridae: cephalochordate) contains a large number of duplicated genes or pseudogenes of cholinesterases. Sequence comparison and tree constructions raise the question of considering the atypical ChE studied in this organism as a representative of ancient BChE. Thus nematodes, arthropods, annelids, molluscs, and vertebrates typically possess two paralogous genes coding for cholinesterases. The origin of the duplication(s) is discussed. The mode of attachment through alternative C-terminal coding exons seems to have evolved independently from the catalytic part of the gene. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  18. Multi-locus phylogenetic analysis reveals the pattern and tempo of bony fish evolution

    PubMed Central

    Broughton, Richard E.; Betancur-R., Ricardo; Li, Chenhong; Arratia, Gloria; Ortí, Guillermo

    2013-01-01

    Over half of all vertebrates are “fishes”, which exhibit enormous diversity in morphology, physiology, behavior, reproductive biology, and ecology. Investigation of fundamental areas of vertebrate biology depend critically on a robust phylogeny of fishes, yet evolutionary relationships among the major actinopterygian and sarcopterygian lineages have not been conclusively resolved. Although a consensus phylogeny of teleosts has been emerging recently, it has been based on analyses of various subsets of actinopterygian taxa, but not on a full sample of all bony fishes. Here we conducted a comprehensive phylogenetic study on a broad taxonomic sample of 61 actinopterygian and sarcopterygian lineages (with a chondrichthyan outgroup) using a molecular data set of 21 independent loci. These data yielded a resolved phylogenetic hypothesis for extant Osteichthyes, including 1) reciprocally monophyletic Sarcopterygii and Actinopterygii, as currently understood, with polypteriforms as the first diverging lineage within Actinopterygii; 2) a monophyletic group containing gars and bowfin (= Holostei) as sister group to teleosts; and 3) the earliest diverging lineage among teleosts being Elopomorpha, rather than Osteoglossomorpha. Relaxed-clock dating analysis employing a set of 24 newly applied fossil calibrations reveals divergence times that are more consistent with paleontological estimates than previous studies. Establishing a new phylogenetic pattern with accurate divergence dates for bony fishes illustrates several areas where the fossil record is incomplete and provides critical new insights on diversification of this important vertebrate group. PMID:23788273

  19. Provisioning rates and time budgets of adult and nestling Bald Eagles at Inland Wisconsin nests

    USGS Publications Warehouse

    Keith, Warnke D.; Andersen, D.E.; Dykstra, C.R.; Meyer, M.W.; Karasov, W.H.

    2002-01-01

    We used a remote video recording system and direct observation to quantify provisioning rate and adult and nestling behavior at Bald Eagle (Haliaeetus leucocephalus) nests in north-central Wisconsin in 1992 (N = 5) and 1993 (N = 8). Eagles nesting in this region have a high reproductive rate (??? 1.3 young/occupied territory), and the number of occupied territories has expanded nearly three-fold since 1980. The season-long provisioning rate averaged 5.2 prey deliveries/nest/d and 3.0 prey deliveries/nestling/d, and did not vary by year or with nestling number or age. Fish (Osteichthyes) made up 97% of identified prey deliveries followed by reptiles (Reptilia) (1.5%), birds (Aves) (1.2%), and mammals (Mammalia) (0.6%). Nearly 85% of prey items were >15 cm and 90% of the day and was negatively correlated with nestling age. Time adults spent feeding nestlings was negatively correlated with nestling age. Nestlings stood or sat in the nest >30% of the day, began to feed themselves, and exhibited increased mobility in the nest at 6-8 wk. We identified three stages of the nestling period and several benchmarks that may be useful when scheduling data collection for comparison of Bald Eagle nesting behavior. Our results support the hypothesis that food was not limiting this breeding population of Bald Eagles. ?? 2002 The Raptor Research Foundation, Inc.

  20. A Broad Continuum of Aeolian Impact Ripple Sizes on Mars is Allowed by Low Dynamic Wind Pressures

    NASA Astrophysics Data System (ADS)

    Sullivan, R. J., Jr.; Kok, J. F.; Yizhaq, H.

    2017-12-01

    Aeolian impact ripples are generated by impacts of wind-blown sand grains, and are common in environments with loose sand on Earth and Mars. Previous work has shown that, within a fully developed saltation cloud, impact ripple height grows upward into the boundary layer until limited by the effects of increasing wind dynamic pressure at the crest (e.g., lengthening of splash trajectories, or direct entrainment of grains by the wind). On Earth, this process limits ripples of well-sorted 250 µm dune sands to heights of millimeters, and strong winds can impose sufficient lateral dynamic pressure to flatten and erase these ripples. Rover observations show much larger ripple-like bedforms on Mars, raising questions about their formative mechanism. Here, we hypothesize that two factors allow impact ripples to grow much higher on Mars than on Earth: (1) previous work predicts a much larger difference between impact threshold and fluid threshold wind speeds on Mars than on Earth; and (2) recent analysis has revealed how low saltation flux can be initiated and sustained well below fluid threshold on Mars, allowing impact ripples to migrate entirely under prevailing conditions of relatively low wind speeds in the thin martian atmosphere. Under these circumstances, martian ripples would need to grow much larger than on Earth before reaching their maximum height limited by wind dynamic pressure effects. Because the initial size of impact ripples is similar on Mars and Earth, this should generate a much broader continuum of impact ripple sizes on Mars. Compared with Earth, far more time should be needed on Mars for impact ripples to achieve their maximum possible size. Consequently, in cases where wind azimuths are mixed but one azimuth is more dominant than others, martian impact ripples of all sizes can exist together in the same setting, with the largest examples reflecting the most common/formative wind azimuths. In cases where wind azimuth is not dominated by a single

  1. Interactions between landslides and landscape evolution using a sediment flux-dependent bedrock incision model incorporating bed macro-roughness

    NASA Astrophysics Data System (ADS)

    Kwang, J. S.; Parker, G.

    2017-12-01

    Many landscape evolution models incorporate sediment removal as a quasi-equilibrium process via the Stream Power Incision Model, or otherwise incorporate sediment supply to mixed bedrock-alluvial channels according to a quasi-steady relation between channel incision and hillslope production. Yet in actively uplifting landscapes, hillslope production is often a highly punctuated phenomenon governed by landslides. We investigate the following key question: how does a landscape subject to punctuated sediment supply differ from one with a steady supply at the same rate? To do this, we incorporate punctuated supply into the Macro Roughness Saltation Abrasion Alluviation model [Zhang et al., 2015], a descendant of the Capacity Saltation Abrasion model [Sklar and Dietrich, 2004, 2006], that is specifically designed to capture unsteady alluvial morphodynamics. Our model has three modules: a) a bedrock-alluvial channel module, b) a hillslope diffusion module, and c) a stochastically-driven landslide supply module. Sediment in bedrock channels plays two roles in incision: 1) as an abrasive agent that incises the bed via collisions and 2) as a protector that inhibits collisions of sediment on the bed. The abrasion rate is proportional to a bedload transport rate times the areal fraction of bedrock surface that is exposed. The transport rate is equal to the capacity transport rate times the areal fraction of bedrock surface that is covered with alluvium, i.e. cover factor. Here, the incision rate vanishes with either vanishing cover (no tools) or complete cover (no bedrock exposed for abrasion). The properties of and amount of sediment delivered to the channel heavily depend on hillslope dynamics. Therefore, hillslope dynamics are important in determining the rate of incision of bedrock channels. Conversely, bedrock incision drives the production of sediment by lowering the base of hillslopes, creating a feedback. We explore this feedback in our landscape evolution model by

  2. Observations Regarding Small Eolian Dunes and Large Ripples on Mars

    NASA Technical Reports Server (NTRS)

    Edgett, Kenneth S.

    2001-01-01

    Eolian bedforms occur at the interface between a planetary surface and its atmosphere; they present a proxy record of the influence of climate, expressed in sediment transport, over that surface. High resolution images (1.5 - 12 m/pixel) from the Mars Global Surveyor (MGS) Mars Orbiter Camera provide glimpses of the most recent events shaping the martian landscape. Thousands of images exhibit small transverse dunes or large eolian ripples that have crest-to-crest spacings of 10 to 60 m, heights of a few to 10 m. Bedforms of the size and patterns seen in the Mars photographs are rarely described among Earth's eolian landforms; in terms of size and morphology, most of these fall between traditional definitions of "ripples" and "dunes". Dunes are composed chiefly of materials transported by saltation, ripples are smaller forms moved along by the impact of saltating grains (traction). The largest reported eolian ripples on Earth (granule ripples, megaripples) are typically smaller than the bedforms observed on Mars; likewise, most dunes are typically larger. The small dunes and large ripples on Mars come in a variety of relative albedos, despite an early MGS impression that they are all of high albedo. Some ripples occur on the surfaces of sand dunes; these are most likely true granule ripples. However, most of these bedforms occur in troughs, pits, craters, and on deflated plains. Despite impressions early in the MGS mission, they do not occur everywhere (e.g., they are rare on the northern plains) but they do occur at a range of elevations from the highest volcanoes to the deepest basins. Where they occur on a hard substrate among larger sand dunes, the big dunes have over-ridden the smaller bedforms, indicating that the smaller features are older and perhaps indurated or very coarse-grained. At other locales, the small bedforms have been mantled by material settled from suspension, in other cases they are being exhumed and may be lithified. Still other examples are

  3. Coupled large eddy simulation and discrete element model of bedload motion

    NASA Astrophysics Data System (ADS)

    Furbish, D.; Schmeeckle, M. W.

    2011-12-01

    We combine a three-dimensional large eddy simulation of turbulence to a three-dimensional discrete element model of turbulence. The large eddy simulation of the turbulent fluid is extended into the bed composed of non-moving particles by adding resistance terms to the Navier-Stokes equations in accordance with the Darcy-Forchheimer law. This allows the turbulent velocity and pressure fluctuations to penetrate the bed of discrete particles, and this addition of a porous zone results in turbulence structures above the bed that are similar to previous experimental and numerical results for hydraulically-rough beds. For example, we reproduce low-speed streaks that are less coherent than those over smooth-beds due to the episodic outflow of fluid from the bed. Local resistance terms are also added to the Navier-Stokes equations to account for the drag of individual moving particles. The interaction of the spherical particles utilizes a standard DEM soft-sphere Hertz model. We use only a simple drag model to calculate the fluid forces on the particles. The model reproduces an exponential distribution of bedload particle velocities that we have found experimentally using high-speed video of a flat bed of moving sand in a recirculating water flume. The exponential distribution of velocity results from the motion of many particles that are nearly constantly in contact with other bed particles and come to rest after short distances, in combination with a relatively few particles that are entrained further above the bed and have velocities approaching that of the fluid. Entrainment and motion "hot spots" are evident that are not perfectly correlated with the local, instantaneous fluid velocity. Zones of the bed that have recently experienced motion are more susceptible to motion because of the local configuration of particle contacts. The paradigm of a characteristic saltation hop length in riverine bedload transport has infused many aspects of geomorphic thought, including

  4. Modeling Sediment Transport Using a Lagrangian Particle Tracking Algorithm Coupled with High-Resolution Large Eddy Simulations: a Critical Analysis of Model Limits and Sensitivity

    NASA Astrophysics Data System (ADS)

    Garcia, M. H.

    2016-12-01

    , (2011), Lagrangian model of bed-load transport in turbulent junction flows, Journal of Fluid Mechanics, 666,36-76. Niño and García, (1994), Gravel saltation: 2. Modeling, Water Resources Research, 30(6),1915-1924. Niño et al., (1994), Gravel saltation: 1. Experiments, Water Resources Research, 30(6), 1907-1914.

  5. Identification of Hepatozoon erhardovae Krampitz, 1964 from bank voles (Myodes glareolus) and fleas in Southern Hungary.

    PubMed

    Rigó, Krisztina; Majoros, Gábor; Szekeres, Sándor; Molnár, Imola; Jablonszky, Mónika; Majláthová, Viktória; Majláth, Igor; Földvári, Gábor

    2016-06-01

    In order to investigate the prevalence and life cycle of apicomplexan parasites, small mammals were live-trapped with modified Sherman traps in Southern Hungary between 2010 and 2012. Altogether, 528 rodents (Apodemus flavicollis Melchior, 1834, Apodemus agrarius Pallas, 1771, Myodes glareolus Schreber, 1780, Microtus agrestis Linnaeus, 1761, Mus musculus Linnaeus, 1758 and Micromys minutus Pallas, 1771) were collected and four shrews (Sorex spp.) were by-catched. Captured animals belonging to non-protected species were euthanized, and spleen samples were preserved for histological and molecular analyses. During the examination of spleen smears, Hepatozoon parasites were observed in eight out of 48 bank voles (M. glareolus). DNA was isolated from altogether 221 spleen samples, and 18S rDNA was amplified using two different PCR protocols. The eight bank vole samples were positive with PCR, but none of the other M. glareolus spleen samples or any of the tissue samples from other species were found to be infected. Sequenced amplicons were very similar to Hepatozoon spp. detected in M. glareolus in Spain and Poland. Ectoparasites were collected from the small mammal carcasses and from the vegetation. Hepatozoon DNA was not found in the 181 ticks removed from the small mammals or in the 162 ticks collected with flagging, but was detected in all three flea species (4/43 Megabothris turbidus Rothschild, 1909, 3/10 Ctenophthalmus assimilis Taschenberg, 1880 and 7/78 Ctenophthalmus agyrtes Heller, 1896). Based on gamont morphology, vertebrate and arthropod host species and DNA sequences, the parasites in our study can be identified as Hepatozoon erhardovae.

  6. Pet snakes illegally marketed in Brazil: Climatic viability and establishment risk.

    PubMed

    Fonseca, Érica; Solé, Mirco; Rödder, Dennis; de Marco, Paulo

    2017-01-01

    Invasive species are one among many threats to biodiversity. Brazil has been spared, generically, of several destructive invasive species. Reports of invasive snakes' populations are nonexistent, but the illegal pet trade might change this scenario. Despite the Brazilian laws forbid to import most animals, illegal trade is frequently observed and propagules are found in the wild. The high species richness within Brazilian biomes and accelerated fragmentation of natural reserves are a critical factors facilitating successful invasion. An efficient way to ease damages caused by invasive species is identifying potential invaders and consequent prevention of introductions. For the identification of potential invaders many factors need to be considered, including estimates of climate matching between areas (native vs. invaded). Ecological niche modelling has been widely used to predict potential areas for invasion and is an important tool for conservation biology. This study evaluates the potential geographical distribution and establishment risk of Lampropeltis getula (Linnaeus, 1766), Lampropeltis triangulum (Lacépède, 1789), Pantherophis guttatus (Linnaeus, 1766), Python bivittatus Kuhl, 1820 and Python regius (Shaw, 1802) through the Maximum Entropy modelling approach to estimate the potential distribution of the species within Brazil and qualitative evaluation of specific biological attributes. Our results suggest that the North and Midwest regions harbor major suitable areas. Furthermore, P. bivittatus and P. guttatus were suggested to have the highest invasive potential among the analyzed species. Potentially suitable areas for these species were predicted within areas which are highly relevant for Brazilian biodiversity, including several conservation units. Therefore, these areas require special attention and preventive measures should be adopted.

  7. Pet snakes illegally marketed in Brazil: Climatic viability and establishment risk

    PubMed Central

    Rödder, Dennis; de Marco, Paulo

    2017-01-01

    Invasive species are one among many threats to biodiversity. Brazil has been spared, generically, of several destructive invasive species. Reports of invasive snakes’ populations are nonexistent, but the illegal pet trade might change this scenario. Despite the Brazilian laws forbid to import most animals, illegal trade is frequently observed and propagules are found in the wild. The high species richness within Brazilian biomes and accelerated fragmentation of natural reserves are a critical factors facilitating successful invasion. An efficient way to ease damages caused by invasive species is identifying potential invaders and consequent prevention of introductions. For the identification of potential invaders many factors need to be considered, including estimates of climate matching between areas (native vs. invaded). Ecological niche modelling has been widely used to predict potential areas for invasion and is an important tool for conservation biology. This study evaluates the potential geographical distribution and establishment risk of Lampropeltis getula (Linnaeus, 1766), Lampropeltis triangulum (Lacépède, 1789), Pantherophis guttatus (Linnaeus, 1766), Python bivittatus Kuhl, 1820 and Python regius (Shaw, 1802) through the Maximum Entropy modelling approach to estimate the potential distribution of the species within Brazil and qualitative evaluation of specific biological attributes. Our results suggest that the North and Midwest regions harbor major suitable areas. Furthermore, P. bivittatus and P. guttatus were suggested to have the highest invasive potential among the analyzed species. Potentially suitable areas for these species were predicted within areas which are highly relevant for Brazilian biodiversity, including several conservation units. Therefore, these areas require special attention and preventive measures should be adopted. PMID:28817630

  8. First records of parasitic copepods (Crustacea, Siphonostomatoida) from marine fishes in Korea.

    PubMed

    Venmathi Maran, B A; Soh, H Y; Hwang, U W; Chang, C Y; Myoung, J G

    2015-06-01

    The knowledge of the biodiversity of parasitic copepods in South Korea is increasing. Interestingly we report here, some parasitic copepods considered as the first record of findings from Korea. Nine species of parasitic copepods (Siphonostomatoida) including six genera of three different families [Caligidae (7), Lernaeopodidae (1), Lernanthropidae (1)] were recovered from eight species of wild fishes in Korea: 1) Caligus hoplognathi Yamaguti & Yamasu, 1959 (♀, ♂) from the body surface of barred knifejaw Oplegnathus fasciatus (Temminck & Schlegel); 2) Caligus lagocephali Pillai, 1961 (♀) from the gills of panther puffer Takifugu pardalis (Temminck & Schlegel); 3) Euryphorus brachypterus (Gerstaecker, 1853) (♀, ♂) from the opercular cavity of Atlantic bluefin tuna Thunnus thynnus (Linnaeus); 4) Euryphorus nordmanni Milne Edwards, 1840 (♀, ♂) from the opercular cavity of common dolphin fish Coryphaena hippurus Linnaeus; 5) Gloiopotes huttoni (Thomson) (♀, ♂) from the body surface of black marlin Istiompax indica (Cuvier); 6) Lepeophtheirus hapalogenyos Yamaguti & Yamasu, 1959 (♀) from the gill filaments of O. fasciatus; 7) Lepeophtheirus sekii Yamaguti, 1936 (♀, ♂) from the body surface of red seabream Pagrus major (Temminck & Schlegel); 8) Brachiella thynni Cuvier, 1830 (♀) from the body surface of longfin tuna or albacore Thunnus alalunga (Bonnaterre); 9) Lernanthropinus sphyraenae (Yamaguti & Yamasu, 1959) (♀) from the gill filaments of moon fish Mene maculata (Bloch & Schneider). Since the female was already reported in Korea, it is a new record for the male of C. hoplognathi. A checklist for the parasitic copepods of the family Caligidae, Lernaeopodidae and Lernanthropidae of Korea is provided.

  9. Antioxidant activity and mineral composition of three Mediterranean common seaweeds from Abu-Qir Bay, Egypt

    PubMed Central

    Khairy, Hanan M.; El-Sheikh, Mohamed A.

    2015-01-01

    Antioxidant activity and mineral composition were evaluated seasonally from spring to autumn 2010 in the three common seaweeds Ulva lactuca Linnaeus (Chlorophyta), Jania rubens (Linnaeus) J.V. Lamouroux and Pterocladia capillacea (S.G. Gmelin) Bornet (Rhodophyta). The antioxidant activity was measured with β-carotene, total phenol content and DPPH (2,2-diphenyl-1-picrylhydrazyl). Seaweeds were collected from the rocky site near Boughaz El-Maadya Abu-Qir Bay of Alexandria, Egypt. The results showed maximum increase of β-carotene in P. capillacea during summer. A significant increase in total phenolic content at P ⩽ 0.05 was found in the red alga (J. rubens) during summer. Also, U. lactuca showed the maximum antioxidant scavenging activity especially during summer. Minerals in all investigated samples were higher than those in conventional edible vegetables. Na/K ratio ranged between 0.78 and 2.4 mg/100 g, which is a favorable value. All trace metals exceeded the recommended doses by Reference Nutrient Intake (RNI). During summer season, it was found that Cu = 2.02 ± 0.13 and Cr = 0.46 ± 0.14 mg/100 g in U. lactuca and Fe had a suitable concentration (18.37 ± 0.5 mg/100 g) in P. capillacea. The studied species were rich in carotenoids, phenolic compounds, DPPH free radicals and minerals, therefore, they can be used as potential source of health food in human diets and may be of use to food industry. PMID:26288568

  10. Ribosomal DNA in diploid and polyploid Setaria (Poaceae) species: number and distribution

    PubMed Central

    Nani, Thaís Furtado; Cenzi, Gisele; Pereira, Daniele Lais; Davide, Lisete Chamma; Techio, Vânia Helena

    2015-01-01

    Abstract Setaria Beauvois, 1812 is a genus of economically important forage species, including Setaria italica (Linnaeus, 1753) Beauvois, 1812 and Setaria viridis (Linnaeus, 1753) Beauvois, 1812, closely related species and considered as model systems for studies of C4 plants. However, complications and uncertainties related to taxonomy of other species of the genus are frequent due to the existence of numerous synonyms for the same species or multiple species with the same name, and overlapping of morphological characteristics. Cytogenetic studies in Setaria can be useful for taxonomic and evolutionary studies as well as for applications in breeding. Thus, this study is aimed at locating 45S and 5S rDNA sites through fluorescent in situ hybridization (FISH) in Setaria italica, Setaria viridis and Setaria sphacelata (Schumacher, 1827) Stapf, Hubbard, Moss, 1929 cultivars (cvs.) Narok and Nandi. Setaria italica and Setaria viridis have 18 chromosomes with karyotype formulas 6m + 3sm and 9m, respectively. The location of 45S and 5S rDNA for these species was in different chromosome pairs among the evaluated species. Setaria viridis presented a more symmetrical karyotype, strengthening the ancestral relationship with Setaria italica. Setaria sphacelata cvs. Narok and Nandi have 36 chromosomes, and karyotype formulas 11m+7sm and 16m+2sm, respectively. The 45S rDNA signals for both cultivars were also observed in distinct chromosome pairs; however chromosomes bearing 5S rDNA are conserved. Karyotypic variations found among the studied species are evidence of chromosomal rearrangements. PMID:26753080

  11. Genotoxicity of freshwater ecosystem shows DNA damage in preponderant fish as validated by in vivo micronucleus induction in gill and kidney erythrocytes.

    PubMed

    Obiakor, M O; Okonkwo, J C; Ezeonyejiaku, C D

    2014-12-01

    Genotoxicity of Anambra River was studied by micronucleus (MN) assay of preponderant fish species in the river. The micronucleus indices obtained were used as biomarker to estimate and predict pollution profile and possible danger of feeding on the aquatic species. Micronuclei profile of the fish was measured from gill and kidney erythrocytes using microscopic technique. Season, species and location effects on micronuclei, together with their interactions were also determined. Two major seasons (rainy and dry) and preponderant fish species in the river (Synodontis clarias, Linnaeus, 1758 and Tilapia nilotica, Linnaeus, 1757) were studied at five distinct locations that displayed differential environmental stresses. The study showed that the micronucleus index of fish is an excellent biomarker for measuring pollution level and genotoxicity of freshwater habitat. Season, species of fish and location affect micronuclei profile of the fish species sampled in the river. Disease outbreak among rural dwellers depending on the river for domestic and other uses is imminent and they lack knowledge on its health implication. Moreover, the study maintained that the micronuclei in fish could be measured from either the gill or kidney; however, gill is more efficient as it enables collection of several samples from the same individuals without sacrificing it, and Synodontis clarias fish species appeared to be more vulnerable to the genotoxic damage than Tilapia nilotica. Consequently, the study recommended regular monitoring (micronucleus tests) of edible aquatic life such as Synodontis clarias in order to eliminate the danger of people feeding on toxic metals, some of which are carcinogenic. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Seasonal erosion and restoration of Mars' northern polar dunes.

    PubMed

    Hansen, C J; Bourke, M; Bridges, N T; Byrne, S; Colon, C; Diniega, S; Dundas, C; Herkenhoff, K; McEwen, A; Mellon, M; Portyankina, G; Thomas, N

    2011-02-04

    Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO(2) seasonal polar caps. Numerous dunes in Mars' north polar region have experienced morphological changes within a Mars year, detected in images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter. Dunes show new alcoves, gullies, and dune apron extension. This is followed by remobilization of the fresh deposits by the wind, forming ripples and erasing gullies. The widespread nature of these rapid changes, and the pristine appearance of most dunes in the area, implicates active sand transport in the vast polar erg in Mars' current climate.

  13. Decoupling of mass flux and turbulent wind fluctuations in drifting snow

    NASA Astrophysics Data System (ADS)

    Paterna, E.; Crivelli, P.; Lehning, M.

    2016-05-01

    The wind-driven redistribution of snow has a significant impact on the climate and mass balance of polar and mountainous regions. Locally, it shapes the snow surface, producing dunes and sastrugi. Sediment transport has been mainly represented as a function of the wind strength, and the two processes assumed to be stationary and in equilibrium. The wind flow in the atmospheric boundary layer is unsteady and turbulent, and drifting snow may never reach equilibrium. Our question is therefore: what role do turbulent eddies play in initiating and maintaining drifting snow? To investigate the interaction between drifting snow and turbulence experimentally, we conducted several wind tunnel measurements of drifting snow over naturally deposited snow covers. We observed a coupling between snow transport and turbulent flow only in a weak saltation regime. In stronger regimes it self-organizes developing its own length scales and efficiently decoupling from the wind forcing.

  14. Titan's Complex Chemistry: Insights from the Lab

    NASA Astrophysics Data System (ADS)

    Horst, Sarah

    2018-06-01

    The Cassini-Huygens mission revealed Titan to be a complex world with physical processes reminiscent of other terrestrial planets, but chemistry that is unlike anywhere else in the Solar System. Titan's complex atmospheric chemistry converts N2 and CH4 into numerous, abundant organic molecules ranging from relatively simple hydrocarbons to ions with mass to charge ratios up to 10,000 amu/q. The molecules eventually settle to the surface where they can participate in and be modified by geological processes such as aeolian and fluvial erosion or undergo subsequent chemistry in Titan's lakes and seas or impact craters and potential cryovolcanic flows. From the processes leading to massive ion formation in the atmosphere to the behavior of saltating organic sands on the surface, laboratory experiments are playing a pivotal role in understanding Titan and expanding our understanding of planetary processes into new, exciting phase space.

  15. Seasonal erosion and restoration of Mars' northern polar dunes

    USGS Publications Warehouse

    Hansen, C.J.; Bourke, M.; Bridges, N.T.; Byrne, S.; Colon, C.; Diniega, S.; Dundas, C.; Herkenhoff, K.; McEwen, A.; Mellon, M.; Portyankina, G.; Thomas, N.

    2011-01-01

    Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO 2 seasonal polar caps. Numerous dunes in Mars' north polar region have experienced morphological changes within a Mars year, detected in images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter. Dunes show new alcoves, gullies, and dune apron extension. This is followed by remobilization of the fresh deposits by the wind, forming ripples and erasing gullies. The widespread nature of these rapid changes, and the pristine appearance of most dunes in the area, implicates active sand transport in the vast polar erg in Mars' current climate.

  16. On newly and recently recorded species of the genus Lema Fabricius (Coleoptera, Chrysomelidae, Criocerinae) from Taiwan

    PubMed Central

    Lee, Chi-Feng; Matsumura, Yoko

    2013-01-01

    Abstract New records of four species (Lema lacertosa Lacordaire, 1845, Lema diversipes Pic, 1921, Lema cyanella (Linnaeus, 1758), Lema trivittata trivittata Say, 1824 and additional information on one recently recorded species (Lema solani Fabricius, 1798) are reported for Taiwan. Lema diversipes Pic, 1921 is removed from synonymy with Lema lacertosa Lacordaire, 1845; both species are redescribed. A lectotype is designated for Lema phungi Pic, 1924. The synonymies of Lema phungi Pic, 1924 and Lema jeanvoinei Pic, 1932 with Lema lacertosa Lacordaire, 1845 are supported. A revised key to the known species in Taiwan is provided. PMID:23653513

  17. [Role of helminth antigens in the abnormal mitosis of bone marrow cells in laboratory animals].

    PubMed

    Sivkova, T N; Tatarnikova, N A; Berezhko, V K; Benediktov, I I

    2013-01-01

    The intraabdominal administration of somatic extracts of the cestodes Hydatigera taeniaformis Batsch 1786, Lamarck, 1816 and Diphyllobothrium latum Linnaeus, 1758 and the nematodes Anisakis simplex larva Rudolphi 1809, Toxocara canis Railliet et Henry, 1912 in albino mice proved that these helminths had a karyopathic effect on the bone marrow cells of the animals. The antigenic composition of these extracts was investigated using the agar gel immunodiffusion test. The antigenic composition of the parasites was ascertained to affect their karyopathic properties. The amount of antigens and their foreignness caused a marked karyopathic effect on the bone marrow cells of laboratory animals during intraabdominal administration.

  18. Parasitic amoebae found in water bodies of Ukraine.

    PubMed

    Patsyuk, Marina

    2017-12-01

    Two parasitic amoebian species are found in mollusks of the water bodies of Ukraine. Vahlkampfia sp. is found in hepatopankreas of Unio conus Spengler, 1793, and Acanthamoeba sp. is observed in mantle cavity of Viviparus viviparus Linnaeus, 1758. For these protist species, the mollusks are shown to be intermediate hosts where amoebae feed and reproduce. An experimental infection with Vahlkampfia sp. and Acanthamoeba sp. was not successful, no pathological changes in mollusks were observed. These amoebae are successfully cultured in fresh water and agar medium, hence we can safely consider them free-living. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    Lakshmanan, P.T.; Nambisan, P.N.K.

    Bivalves are well known for their ability to concentrate heavy metals in their tissue from environmental water. Experimental studies on the accumulation of these pollutants by molluscs have been extensively conducted. The depuration of accumulated metals in a toxicant free medium has also been studied. Bivalve molluscs may form useful tools in monitoring heavy metal pollution. However, such studies are scant in tropical species. This paper reports the bioaccumulation and depuration of Hg, Cu, Zn and Pb by the mussel Perna viridis (Linnaeus) from seawater and explores its suitability as an indicator organism for metal pollution.

  20. New records and updated checklist of Cicadomorpha (Hemiptera: Auchenorrhyncha) species from Greece.

    PubMed

    Thanou, Zoi N; Afentoulis, Dimitrios G; Koufopoulou, Panagiota; Ampatzi, Argyro P; Lekkou, Sofia D; Koutsogiannopoulou, Αikaterini; Bravou, Anastasia A; Stamatakou, Georgia D; Voulgaraki, Konstantina N; Piperkas, Anastasios; Chaldaiou, Aikaterini; Kalaitzaki, Argyro P; Tsagkarakis, Antonios E

    2018-04-20

    Seventeen auchenorrhynchan species of the family Cicadellidae are recorded from Greece for the first time: Euscelidius variegatus (Kirschbaum 1858), Euscelis ohausi (Wagner 1939), Psammotettix notatus (Melichar 1896), Psammotettix striatus (Linnaeus 1758), Psammotettix sabulicola (Curtis 1837), Anzygina honiloa (Kirkaldy 1906), Arboridia versuta (Melichar 1897), Edwardsiana ishidae (Matsumura 1932), Edwardsiana tersa (Edwards 1914), Eupteryx decemnotata (Rey 1891), Eupteryx curtisii (Flor 1861), Eupteryx rostrata (Ribaut 1936), Frutioidia sanguinosa (Rey 1891), Zygina rosea (Flor 1861), Zygina suavis (Rey 1891), Zygina tiliae (Fallen 1806), Anaceratagallia frisia (Wagner 1939). Faunistic and distributional data notes are given for each species and a complete, updated species checklist for Greece is provided.

  1. Parasitoids of Monochamus galloprovincialis (Coleoptera, Cerambycidae), vector of the pine wood nematode, with identification key for the Palaearctic region

    PubMed Central

    Petersen-Silva, Ricardo; Pujade-Villar, Juli; Naves, Pedro; Edmundo Sousa; Belokobylskij,  Sergey

    2012-01-01

    Abstract The parasitoid complex associated with Monochamus galloprovincialis (Olivier), vector of the pine wood nematode, is discussed. Four species of the family Braconidae and one Ichneumonidae were found associated with Monochamus galloprovincialis in Portugal, namely Atanycolus denigrator (Linnaeus), Atanycolus ivanowi (Kokujev), Cyanopterus flavator (Fabricius), Doryctes striatellus (Nees) (Braconidae), and Xorides depressus (Holmgren) (Ichneumonidae). Atanycolus ivanowi, Atanycolus denigrator, Doryctes striatellus and Xorides depressus are new species for Portugal fauna, and Monochamus galloprovincialis is recorded as a new host of Xorides depressus. A key for determination of the ichneumonoid parasitoids of the pine sawyer is provided for the Palaearctic fauna. PMID:23378807

  2. Review of Gasteruption Latreille (Hymenoptera, Gasteruptiidae) from Iran and Turkey, with the description of 15 new species

    PubMed Central

    van Achterberg, Cornelis; Talebi, Ali Asghar

    2014-01-01

    Abstract The genus Gasteruption Latreille, 1796 (Hymenoptera: Evanioidea: Gasteruptiidae: Gasteruptiinae) from North Iran and Turkey is revised, keyed and fully illustrated for the first time. In total 36 species are treated of which 33 are recorded from Turkey and 23 from Iran. Fifteen species are new for science: Gasteruption aciculatum van Achterberg, sp. n., Gasteruption agrenum van Achterberg, sp. n., Gasteruption brevibasale van Achterberg & Saure, sp. n., Gasteruption coriacoxale van Achterberg, sp. n., Gasteruption flavimarginatum van Achterberg, sp. n., Gasteruption heminitidum van Achterberg, sp. n., Gasteruption henseni van Achterberg, sp. n., Gasteruption ischnolaimum van Achterberg, sp. n., Gasteruption nigrapiculatum van Achterberg, sp. n., Gasteruption paglianoi van Achterberg & Saure, sp. n., Gasteruption pseudolaticeps van Achterberg, sp. n., Gasteruption punctifrons van Achterberg, sp. n., Gasteruption schmideggeri van Achterberg & Saure, sp. n., Gasteruption scorteum van Achterberg, sp. n. and Gasteruption smitorum van Achterberg, sp. n. Twenty-one species are reported new for Turkey and 16 species new for Iran. Fifteen new synonyms are proposed: Foenus terrestris Tournier, 1877, Gasteruption trifossulatum Kieffer, 1904, and Gasteruption ignoratum Kieffer, 1912, of Gasteruption caucasicum (Guérin-Méneville, 1844); Gasteruption daisyi Alekseev, 1993, of Gasteruption dolichoderum Schletterer, 1889; Gasteruption assectator var. nitidulum Schletterer, 1885, of Gasteruption freyi (Tournier, 1877); Gasteruption schossmannae Madl, 1987, of Gasteruption hastator (Fabricius, 1804); Gasteryption fallaciosum Semenov, 1892, Gasteruption dubiosum Semenov, 1892 and Gasteruption obsoletum Semenov, 1892, of Gasteruption insidiosum Semenov, 1892; Gasteryption schewyrewi Semenov, 1892, of Gasteruption jaculator (Linnaeus, 1758); Gasteruption floreum Szépligeti, 1903, of Gasteruption lugubre Schletterer, 1889; Gasteruption trichotomma Kieffer, 1904, and

  3. Cryopreservation of sperm in Grey mullet Mugil cephalus (Linnaeus, 1758).

    PubMed

    Balamurugan, Ramachandran; Munuswamy, Natesan

    2017-10-01

    The aim of this study was to document the effects of cryopreservation on sperm motility and viability in Grey mullet Mugil cephalus. Cryopreservation of sperm was attempted by using two extenders ringer solution for marine fish (RSMF) and V2 extender (V2E) and cryoprotectants dimethylacetamide (DMA), dimethylsulfoxide (DMSO), ethylene glycol (EG), glycerol (GLY), propylene glycol (PG) and methanol (MeOH). Cryoprotectants were assessed at different concentrations individually as well as in combination with varying equilibration times (10 and 30min). For optimization of freezing rate, four freezing protocols (-5, -10, -20 and -30°C/min) were evaluated. After achieving final temperature, samples were plunged in liquid nitrogen (-196°C) and stored for a week. Samples were subsequently thawed in a water bath at 30°C for assessment of sperm motility and viability. Results indicated that cryomedium constituting of V2E extender+10% glycerol with a dilution ratio of 1:1 (sperm: cryomedium) at an equilibration time of 5 to- 10min and freezing rate of -20°C/min was more desirable compared with other factors that were assessed. Use of this protocol resulted in retaining the greatest sperm motility grade 3.0±0.0 (50%-80% sperm movement, fast swimming) and 48.19±3.12% of sperm viability. The results of the present study, therefore, provide base-line data for establishing a protocol for sperm cryopreservation in M.cephalus. Further studies are, however, required for optimization of most suitable sperm cryopreservation protocol. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Acanthocephala Larvae parasitizing Ameiva ameiva ameiva (Linnaeus, 1758) (Squamata: Teiidae).

    PubMed

    Macedo, Lilian Cristina; Melo, Francisco Tiago de Vasconcelos; Ávila-Pires, Teresa Cristina Sauer; Giese, Elane Guerreiro; dos Santos, Jeannie Nascimento

    2016-01-01

    Knowledge concerning the taxonomy and biology of species of Acanthocephala, helminth parasites of the helminth species of the phylum Acanthocephala, parasites of lizards in Brazilian Amazonia, is still insufficient, but reports of Acanthocephala in reptiles are becoming increasingly common in the literature. Cystacanth-stage Acanthocephalan larvae have been found in the visceral peritoneum during necropsy of Ameiva ameiva ameivalizards from the "Osvaldo Rodrigues da Cunha" Herpetology Collection of the Emílio Goeldi Museum, Belém, Pará, Brazil. The aim of this study was to present the morphological study of the Acanthocephala larvae found in A. ameiva ameiva lizard.

  5. The existence of Dracunculus medinensis (Linnaeus, 1758) in Turkana, Kenya.

    PubMed

    Macpherson, C N

    1981-01-01

    Dracontiasis has been previously reported in southern Sudan, northern Uganda and north-west Eritrea but this is the first report of autochthonous cases in Turkana, Kenya. Five Turkana tribesmen, three females from the same family, one young boy and an adult male were being treated for guinea-worm at the dispensary in Lokichogio, northern Turkana District. The three women had recently returned from southern Sudan, where the disease is endemic, but the two male tribesmen had only lived in and around the Lokichogio region. The methods used in obtaining water from water-holes dug in dry river beds provide an ideal situation for Dracunculus transmission amongst the tribesmen; this parasite may therefore become a problem in this remote impoverished area.

  6. The Habitat of Yellow Mouth Turban Turbo Chrysostomus, Linnaeus, 1758

    NASA Astrophysics Data System (ADS)

    Soekendarsi, E.

    2018-03-01

    In general, yellow mouth turban snail Turbo chrysostomus L. 1758 was found in intertidal and coral reef area. This animal is active at night (nocturnal) and settles the coral reef-flats area to do its activity as substrate. In doing its activity, yellow mouth turban snail can be found in the depth of 50 cm until 4 m of tidal area. The adult yellow mouth turban snails are found in great number at intertidal area’s border and at coastal area of coral reef-flats. Methodology that was used in this study is visual analysis (descriptive method), and divided into two parameters which were observed, i.e. abiotic and biotic. Abiotic components that were measured are; Oxygen (ppm), pH, Water Temperature (°C), Salinity (ppm), Ammonia (mg/L), Nitrate (mg/L), Nitrite (mg/L), and Calsium Carbonat (mg/L).Whereas, biotic components that were measured are; substrates, seaweeds, other organisms, and epilithon. The observation’s result of yellow mouth turban snail’s environmental condition showed: abiotic condition of the waters consists of oxygen 3-5 ppm, seawater pH 7-8, seawater temperature 23-26°C, and the salinity of 32-33 ppm. The Habitat of yellow mouth turban snail settled the reef-flats area that is overgrown covered by seaweed Sargassum sp. as the place to do its activity.

  7. Modeling Dengue vector population using remotely sensed data and machine learning.

    PubMed

    Scavuzzo, Juan M; Trucco, Francisco; Espinosa, Manuel; Tauro, Carolina B; Abril, Marcelo; Scavuzzo, Carlos M; Frery, Alejandro C

    2018-05-16

    Mosquitoes are vectors of many human diseases. In particular, Aedes ægypti (Linnaeus) is the main vector for Chikungunya, Dengue, and Zika viruses in Latin America and it represents a global threat. Public health policies that aim at combating this vector require dependable and timely information, which is usually expensive to obtain with field campaigns. For this reason, several efforts have been done to use remote sensing due to its reduced cost. The present work includes the temporal modeling of the oviposition activity (measured weekly on 50 ovitraps in a north Argentinean city) of Aedes ægypti (Linnaeus), based on time series of data extracted from operational earth observation satellite images. We use are NDVI, NDWI, LST night, LST day and TRMM-GPM rain from 2012 to 2016 as predictive variables. In contrast to previous works which use linear models, we employ Machine Learning techniques using completely accessible open source toolkits. These models have the advantages of being non-parametric and capable of describing nonlinear relationships between variables. Specifically, in addition to two linear approaches, we assess a support vector machine, an artificial neural networks, a K-nearest neighbors and a decision tree regressor. Considerations are made on parameter tuning and the validation and training approach. The results are compared to linear models used in previous works with similar data sets for generating temporal predictive models. These new tools perform better than linear approaches, in particular nearest neighbor regression (KNNR) performs the best. These results provide better alternatives to be implemented operatively on the Argentine geospatial risk system that is running since 2012. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Trace metals and macroelements in mussels from Chinese coastal waters: National spatial patterns and normalization.

    PubMed

    Lu, Guang-Yuan; Wang, Wen-Xiong

    2018-06-01

    Metal contamination is one of the most ubiquitous and complex problems in the Chinese coastal environment. To explore the large-scale spatial patterns of bioavailable metals, we sampled three major mussels, including 784 blue mussels (Mytilus edulis Linnaeus, 1758) of 14 sites, 224 hard-shelled mussels (Mytilus unguiculatus Valenciennes, 1858) of 4 sites, and 392 green mussels (Perna viridis (Linnaeus, 1758)) of 7 sites, ranging from temperate to tropical coastlines of China, during August and September 2015. The concentrations of macroelements (Na, K, Ca, Mg, and P) and toxic trace metals (Ag, Cd, Cr, Cu, Ni, Pb, Ti, and Zn) in the mussel's whole soft tissues were determined. Among the four Chinese coastal basins, Cd, Ti and Cr in the mussel tissues were the highest at Bohai Sea (BS) and Yellow Sea (YS), and Cu, Ni, Pb and Ag in the mussel tissues were the highest at East China Sea (ECS) and South China Sea (SCS). Zinc concentrations in mussels from YS were significantly higher than those from the other regions. Given the variability of environmental conditions such as salinity and nutrients, we further normalized the measured tissue metal concentrations with tissue Na and P levels. After Na normalization as the salinity proxy, the variability of Cd, Cu, Zn, Ag, and Ni was reduced. Trace elements accumulation in the mussel tissues was significantly related to both macroelements (Na or P) and body dry weight. The present study demonstrated that nonlinear optimization of different elements was necessary in assessing metal bioaccumulation patterns in marine mussels at a large spatial scale. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Surveillance of tick-borne encephalitis virus in wild birds and ticks in Tomsk city and its suburbs (Western Siberia).

    PubMed

    Mikryukova, Tamara P; Moskvitina, Nina S; Kononova, Yulia V; Korobitsyn, Igor G; Kartashov, Mikhail Y; Tyuten Kov, Oleg Y; Protopopova, Elena V; Romanenko, Vladimir N; Chausov, Evgeny V; Gashkov, Sergey I; Konovalova, Svetlana N; Moskvitin, Sergey S; Tupota, Natalya L; Sementsova, Alexandra O; Ternovoi, Vladimir A; Loktev, Valery B

    2014-03-01

    To study the role of wild birds in the transmission of tick borne encephalitis virus (TBEV), we investigated randomly captured wild birds bearing ixodid ticks in a very highly endemic TBE region located in Tomsk city and its suburbs in the south of Western Siberia, Russia. The 779 wild birds representing 60 species were captured carrying a total of 841 ticks, Ixodes pavlovskyi Pom., 1946 (n=531), Ixodes persulcatus P. Sch., 1930 (n=244), and Ixodes plumbeus Leach. 1815 (n=66). The highest average number of ticks per bird in a particular species was found for the fieldfare (Turdus pilaris Linnaeus, 1758) (5.60 ticks/bird) and the tree pipit (Anthus trivialis Linnaeus, 1758) (13.25 ticks/bird). Samples from wild birds and ticks collected in highly endemic periods from 2006 to 2011 were tested for the TBEV markers using monoclonal modified enzyme immunoassay (EIA) and RT-PCR. TBEV RNA and antigen were found in 9.7% and 22.8% samples collected from wild birds, respectively. TBEV markers were also detected in 14.1% I. persulcatus ticks, 5.2% I. pavlovskyi, and 4.2% I. plumbeus ticks collected from wild birds. Two TBEV strains were also isolated on PKE (pig kidney embryo) cells from fieldfare and Blyth's reed warbler (Acrocephalus dumetorum Blyth, 1849). Sequencing of 5'-NCR of TBEV revealed that all TBEV isolates belong to Far Eastern (dominate) and Siberian genotypes. Several phylogenetic subgroups included TBEV sequences novel for the Tomsk region. Our data suggest that wild birds are potential disseminators of TBEV, TBEV-infected ixodid ticks, and possibly other tick-borne infections. Copyright © 2013 Elsevier GmbH. All rights reserved.

  10. Review of Pennella Oken, 1816 (Copepoda: Pennellidae) with a description of Pennella benzi sp. nov., a parasite of Escolar, Lepidocybium flavobrunneum (Pisces) in the northwest Atlantic Ocean.

    PubMed

    Hogans, W E

    2017-03-17

    The genus Pennella Oken, 1816, mesoparasitic copepods from marine fish and mammals, is reviewed with the objective of determining the validity of members of the genus. Details of the external morphological structures of the adult female are presented. Pennella species are differentiated based on a combination of characters: the type of host parasitized, overall length of the parasite, shape, size and configuration of cephalothoracic papillae, segmentation of the first and second antenna, holdfast horn number, shape and configuration, and structure of the abdominal plumes. A new species of Pennella, Pennella benzi sp. nov., is described from the escolar, Lepidocybium flavobrunneum in the northwest Atlantic. Pennella balaenoptera Koren & Danielssen, 1877 is reported from the harbor porpoise (Phocaena phocaena) in the Bay of Fundy, a new locality record. The validity of 44 species is assessed; nine species (P. balaenoptera Koren & Danielssen, 1877, P. benzi sp. nov., P. diodontis Oken, 1816, P. exocoeti (Holten, 1802), P. filosa Linnaeus, 1758, P. hawaiiensis Kazachenko & Kurochkin, 1974, P. instructa Wilson, 1917, P. makaira Hogans, 1988 and P. sagitta Linnaeus, 1758) are considered substantiated and valid; six species (P. elegans Gnanamuthu, 1957, P. longicauda Gnanamuthu, 1957, P. platycephalus Gnanamuthu, 1957, P. remorae Murray, 1856, P. robusta Gnanamuthu, 1957, and P. selaris Kirtisinghe, 1964) exhibit unique characteristics, but are based on descriptions of single specimens, have not been found since the original reports and are considered as species inquirendae; the remaining species are unsubstantiated and invalid based on inadequate or missing original descriptions, or are designated as synonyms of valid species. A key to the valid species of the genus is provided.

  11. Differential repetitive DNA composition in the centromeric region of chromosomes of Amazonian lizard species in the family Teiidae

    PubMed Central

    Carvalho, Natalia D. M.; Carmo, Edson; Neves, Rogerio O.; Schneider, Carlos Henrique; Gross, Maria Claudia

    2016-01-01

    Abstract Differences in heterochromatin distribution patterns and its composition were observed in Amazonian teiid species. Studies have shown repetitive DNA harbors heterochromatic blocks which are located in centromeric and telomeric regions in Ameiva ameiva (Linnaeus, 1758), Kentropyx calcarata (Spix, 1825), Kentropyx pelviceps (Cope, 1868), and Tupinambis teguixin (Linnaeus, 1758). In Cnemidophorus sp.1, repetitive DNA has multiple signals along all chromosomes. The aim of this study was to characterize moderately and highly repetitive DNA sequences by Cot1-DNA from Ameiva ameiva and Cnemidophorus sp.1 genomes through cloning and DNA sequencing, as well as mapping them chromosomally to better understand its organization and genome dynamics. The results of sequencing of DNA libraries obtained by Cot1-DNA showed that different microsatellites, transposons, retrotransposons, and some gene families also comprise the fraction of repetitive DNA in the teiid species. FISH using Cot1-DNA probes isolated from both Ameiva ameiva and Cnemidophorus sp.1 showed these sequences mainly located in heterochromatic centromeric, and telomeric regions in Ameiva ameiva, Kentropyx calcarata, Kentropyx pelviceps, and Tupinambis teguixin chromosomes, indicating they play structural and functional roles in the genome of these species. In Cnemidophorus sp.1, Cot1-DNA probe isolated from Ameiva ameiva had multiple interstitial signals on chromosomes, whereas mapping of Cot1-DNA isolated from the Ameiva ameiva and Cnemidophorus sp.1 highlighted centromeric regions of some chromosomes. Thus, the data obtained showed that many repetitive DNA classes are part of the genome of Ameiva ameiva, Cnemidophorus sp.1, Kentroyx calcarata, Kentropyx pelviceps, and Tupinambis teguixin, and these sequences are shared among the analyzed teiid species, but they were not always allocated at the same chromosome position. PMID:27551343

  12. Bioaccumulation of Heavy Metals in Various Tissues of Some Fish Species and Green Tiger Shrimp (Penaeus semisulcatus) from İskenderun Bay, Turkey, and Risk Assessment for Human Health.

    PubMed

    Kaya, Gokce; Turkoglu, Semra

    2017-12-01

    In this study, concentrations of heavy metals were determined by ICP-MS in the edible tissues of common sole (Solea solea Linnaeus, 1758), whiting (Merlangius merlangus Linnaeus, 1758), silver sillago (Sillago sihama Forsskål, 1775) and muscle-exoskeleton of green tiger shrimp (Penaeus semisulcatus De Haan, 1844), from the seas of İskenderun Bay, Eastern Mediterranean, Turkey, in January-February, 2016. The lowest and highest mean concentrations of Mn, Cr, Cd, Ni, Hg, As, Pb, and Co in fish and shrimp' muscles were found, respectively, as follows: 0.166-0.382, 0.134-0.336, 0.005-0.008, 0.091-0.140, 0.026-0.228, 1.741-29.254, 0.087-0.110, and <0.0005-0.027 mg kg -1 ; in the skin and exoskeleton, the values were found, respectively, as 0.103-15.819, 0.301-0.778, 0.007-0.026, 0.115-0.513, 0.021-0.243, 1.548-17.930, 0.148-0.295, and <0.0005-0.140 mg kg -1 . According to the results, mean concentrations of all metals in the muscles of fish, except for arsenic and chromium, were found to be below certain legal limit values, especially arsenic levels in shrimp that were found to be above all the legal limit values. Also, the hazard quotients (HQ) of individual heavy metals in fish and shrimp, except for As, revealed safe levels for human consumption. However, the HQ values of estimated inorganic As exceeded 1 in the muscles of shrimp (P. semisulcatus), which may constitute a risk to public health.

  13. A new multiplex PCR protocol to detect mixed trypanosomatid infections in species of Apis and Bombus.

    PubMed

    Bartolomé, Carolina; Buendía, María; Benito, María; De la Rúa, Pilar; Ornosa, Concepción; Martín-Hernández, Raquel; Higes, Mariano; Maside, Xulio

    2018-05-01

    Trypanosomatids are highly prevalent pathogens of Hymenoptera; however, most molecular methods used to detect them in Apis and Bombus spp. do not allow the identification of the infecting species, which then becomes expensive and time consuming. To overcome this drawback, we developed a multiplex PCR protocol to readily identify in a single reaction the main trypanosomatids present in these hymenopterans (Lotmaria passim, Crithidia mellificae and Crithidia bombi), which will facilitate the study of their epidemiology and transmission dynamics. A battery of primers, designed to simultaneously amplify fragments of the RNA polymerase II large subunit (RPB1) of L. passim, the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of C. mellificae and the DNA topoisomerase II (TOPII) of C. bombi, was tested for target specificity under single and mixed template conditions using DNA extracted from cell cultures (L. passim ATCC PRA403; C. mellificae ATCC 30254) and from a bumblebee specimen infected with C. bombi only (14_349). Once validated, the performance of the method was assessed using DNA extractions from seven Apis mellifera (Linnaeus, 1758) and five Bombus terrestris (Linnaeus, 1758) field samples infected with trypanosomatids whose identity had been previously determined by PCR-cloning and sequencing (P-C-S). The new method confirmed the results obtained by P-C-S: two of the honeybee samples were parasitized by L. passim, C. mellificae and C. bombi at the same time, whereas the other five were infected with L. passim only. The method confirmed the simultaneous presence of L. passim and C. mellificae in two B. terrestris, where these parasites had not previously been reported. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. The effect of the configuration of a single electrode corona discharge on its acoustic characteristics

    NASA Astrophysics Data System (ADS)

    Zhu, Xinlei; Zhang, Liancheng; Huang, Yifan; Wang, Jin; Liu, Zhen; Yan, Keping

    2017-07-01

    A new sparker system based on pulsed spark discharge with a single electrode has already been utilized for oceanic seismic exploration. However, the electro-acoustic energy efficiency of this system is lower than that of arc discharge based systems. A simple electrode structure was investigated in order to improve the electro-acoustic energy efficiency of the spark discharge. Experiments were carried out on an experimental setup with discharge in water driven by a pulsed power source. The voltage-current waveform, acoustic signal and bubble oscillation were recorded when the relative position of the electrode varied. The electro-acoustic energy efficiency was also calculated. The load voltage had a saltation for the invaginated electrode tip, namely an obvious voltage remnant. The more the electrode tip was invaginated, the larger the pressure peaks and first period became. The results show that electrode recessing into the insulating layer is a simple and effective way to improve the electro-acoustic energy efficiency from 2% to about 4%.

  15. Dust Devils Whip by Spirit

    NASA Technical Reports Server (NTRS)

    2007-01-01

    On sol 1120 (February 26, 2007), the navigation camera aboard NASA's Mars Exploration Rover Spirit captured one of the best dust devils it's seen in its three-plus year mission. The series of navigation camera images were put together to make a dust devil movie.

    The dust devil column is clearly defined and is clearly bent in the down wind direction. Near the end of the movie, the base of the dust devil becomes much wider. The atmospheric science team thinks that this is because the dust devil encountered some sand and therefore produced a 'saltation skirt,' an apron of material that is thrown out of the dust devil because it is too large to be carried up into suspension.

    Also near the end of the movie the dust devil seems to move faster across the surface. This is because Spirit began taking pictures less frequently, and not because the dust devil sped up.

  16. Wind Tunnel Experiments: Influence of Erosion and Deposition on Wind-Packing of New Snow

    NASA Astrophysics Data System (ADS)

    Sommer, C.; Fierz, C. G.; Lehning, M.

    2017-12-01

    We observed the formation of wind crusts in wind tunnel experiments. A SnowMicroPen was used to measure the hardness profile of the snow and a Microsoft Kinect provided distributed snow depth data. Earlier experiments showed that no crust forms without saltation and that the dynamics of erosion and deposition may be a key factor to explain wind-packing. The Kinect data could be used to quantify spatial erosion and deposition patterns and the combination with the SnowMicroPen data allowed to study the effect of erosion and deposition on wind-hardening. We found that erosion had no hardening effect on fresh snow and that deposition is a necessary but not sufficient condition for wind crust formation. Deposited snow was only hardened in wind-exposed areas. The Kinect data was used to calculate the wind-exposure parameter Sx. We observed no significant hardening for Sx>0.25. The variability of resulting wind crust hardnesses at Sx<0.25 was still large, however.

  17. Aeolian features and processes at the Mars Pathfinder landing site

    USGS Publications Warehouse

    Greeley, Ronald; Kraft, Michael; Sullivan, Robert; Wilson, Gregory; Bridges, Nathan; Herkenhoff, Ken; Kuzmin, Ruslan O.; Malin, Michael; Ward, Wes

    1999-01-01

    The Mars Pathfinder landing site contains abundant features attributed to aeolian, or wind, processes. These include wind tails, drift deposits, duneforms of various types, ripplelike features, and ventifacts (the first clearly seen on Mars). Many of these features are consistant with formation involving sand-size particles. Although some features, such as dunes, could develop from saltating sand-size aggregates of finer grains, the discovery of ventifact flutes cut in rocks strongly suggests that at least some of the grains are crystalline, rather than aggregates. Excluding the ventifacts, the orientations of the wind-related features correlate well with the orientations of bright wind steaks seen on Viking Orbiter images in the general area. They also correlate with wind direction predictions from the NASA-Ames General Circulation Model (GCM) which show that the strongest winds in the area occur in the northern hemisphere winter and are directed toward 209°. Copyright 1999 by the American Geophysical Union.

  18. The skylight gradient of luminance helps sandhoppers in sun and moon identification.

    PubMed

    Ugolini, Alberto; Galanti, Giuditta; Mercatelli, Luca

    2012-08-15

    To return to the ecologically optimal zone of the beach, the sandhopper Talitrus saltator (Montagu) maintains a constant sea-land direction based on the sun and moon compasses. In this study, we investigated the role of the skylight gradient of luminance in sun and moon identification under natural and artificial conditions of illumination. Clock-shifted (inverted) sandhoppers tested under the sun (during their subjective night) and under the full moon (during their subjective day) exhibit orientation in accordance with correct identification of the sun and the moon at night. Tested in artificial conditions of illumination at night without the artificial gradient of luminance, the artificial astronomical cue is identified as the moon even when the conditions of illumination allow sun compass orientation during the day. When the artificial gradient of luminance is added, the artificial astronomical cue is identified as the sun. The role of the sky gradient of luminance in sun and moon identification is discussed on the basis of present and past findings.

  19. An Engineered orco Mutation Produces Aberrant Social Behavior and Defective Neural Development in Ants.

    PubMed

    Yan, Hua; Opachaloemphan, Comzit; Mancini, Giacomo; Yang, Huan; Gallitto, Matthew; Mlejnek, Jakub; Leibholz, Alexandra; Haight, Kevin; Ghaninia, Majid; Huo, Lucy; Perry, Michael; Slone, Jesse; Zhou, Xiaofan; Traficante, Maria; Penick, Clint A; Dolezal, Kelly; Gokhale, Kaustubh; Stevens, Kelsey; Fetter-Pruneda, Ingrid; Bonasio, Roberto; Zwiebel, Laurence J; Berger, Shelley L; Liebig, Jürgen; Reinberg, Danny; Desplan, Claude

    2017-08-10

    Ants exhibit cooperative behaviors and advanced forms of sociality that depend on pheromone-mediated communication. Odorant receptor neurons (ORNs) express specific odorant receptors (ORs) encoded by a dramatically expanded gene family in ants. In most eusocial insects, only the queen can transmit genetic information, restricting genetic studies. In contrast, workers in Harpegnathos saltator ants can be converted into gamergates (pseudoqueens) that can found entire colonies. This feature facilitated CRISPR-Cas9 generation of germline mutations in orco, the gene that encodes the obligate co-receptor of all ORs. orco mutations should significantly impact olfaction. We demonstrate striking functions of Orco in odorant perception, reproductive physiology, and social behavior plasticity. Surprisingly, unlike in other insects, loss of OR functionality also dramatically impairs development of the antennal lobe to which ORNs project. Therefore, the development of genetics in Harpegnathos establishes this ant species as a model organism to study the complexity of eusociality. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Wind ripples in low density atmospheres

    NASA Technical Reports Server (NTRS)

    Miller, J. S.; Marshall, J. R.; Greeley, R.

    1987-01-01

    The effect of varying fluid density (rho) on particle transport was examined by conducting tests at atmospheric pressures between 1 and 0.004 bar in the Martian Surface Wind Tunnel (MARSWIT). This study specifically concerns the effect of varying rho on the character of wind ripples, and elicits information concerning generalized ripple models as well as specific geological circumstances for ripple formation such as those prevailing on Mars. Tests were conducted primarily with 95 micron quartz sand, and for each atmospheric pressure chosen, tests were conducted at two freestream wind speeds: 1.1 U*(t) and 1.5 U*(t), where U*(t) is saltation threshold. Preliminary analysis of the data suggests: (1) ballistic ripple wavelength is not at variance with model predictions; (2) an atmospheric pressure of approximately 0.2 bar could represent a discontinuity in ripple behavior; and (4) ripple formation on Mars may not be readily predicted by extrapolation of terrestrial observations.

  1. Loess as a Quaternary paleoenvironmental indicator

    USGS Publications Warehouse

    Muhs, Daniel R.; Prins, M.A.; Machalett, B.

    2014-01-01

    Loess is aeolian sediment that is dominated by silt-sized particles. Unlike either coarser dune sand or finer-grained, long-range-transported dust, loess is relatively poorly sorted, reflecting a combination of transport processes, including saltation, low suspension, and high suspension. Loess can be readily identified in the field; deposits range in thickness from a few centimeters to many tens of meters, and are found over large areas of Eurasia, South and North America (Fig. 1), and smaller areas of New Zealand, Australia, Africa and the Middle East. Loess covers approximately 10% of the Earth’s land surface and is therefore one of the most important terrestrial archives of paleoenvironmental change during the Quaternary. In many regions, loess sections consist of deposits of mostly unaltered sediment with intercalated paleosols. Paleosols represent periods of landscape stability when loess deposition ceased altogether, or at least slowed significantly. Loess can be dated directly using luminescence, radiocarbon, and amino acid geochronology methods.

  2. Prevalence and risk factors of Ascaris lumbricoides (Linnaeus, 1758), Trichuris trichiura (Linnaeus, 1771) and HBV infections in Southwestern China: a community-based cross sectional study.

    PubMed

    Xiao, Peng-Lei; Zhou, Yi-Biao; Chen, Yue; Yang, Ya; Shi, Yan; Gao, Jian-Chuan; Yihuo, Wu-Li; Song, Xiu-Xia; Jiang, Qing-Wu

    2015-12-24

    Intestinal helminths do not cause severe diseases in general, however, when combined with other diseases such as immunodeficiency diseases, there would be massive complications. Infections with Hepatitis B Virus (HBV) may lead to immunological disturbances and defects of cellular immunity and there is a need of clarification whether HBV infections are associated with infections with intestinal helminths. A community-based cross sectional study was conducted in Tezi town, Puge County of the Liangshan Prefecture, southwestern China from October 23rd to November 3rd, 2014. Four hundred and thirty eight people (median age = 37 years, IQR = 22-49) were enrolled in this study. Modified Kato-Katz thick smear was used to detect intestinal helminths. HBV DNA was quantified to confirm HBV infection. Among the 438 participants, 9.1%, 13.5% and 30.6% were infected with HBV, A. lumbricoides (L., 1758) and T. trichiura (L., 1771), respectively; 7.1% (30/438) were infected with both A. lumbricoides and T. trichiura and 2.3% (10/438) were co-infected with HBV and A. lumbricoides. The multivariate logistic regression analysis showed that age (21-30 years versus >50 years: OR = 6.66, 95% CI = 2.15-20.68), drug abuse (OR = 6.96, 95% CI = 1.11-43.90), A. lumbricoides infection (OR = 3.60, 95% CI = 1.48-8.75), fertilization with faeces after disposal (OR = 0.15, 95% CI = 0.04-0.47) and working on a farm (OR = 4.59, 95% CI = 1.44-14.63) were significantly associated with HBV infection. Having toilets at home was negatively related to A. lumbricoides infection (OR = 0.52, 95% CI = 0.27-0.98) and T. trichiura infection (OR = 0.48, 95% CI = 0.28-0.80). Ascaris lumbricoides was independently associated with HBV infection, and faeces might be the medium of HBV transmission. Improving hygiene conditions and habits are essential to reduce the risks of A. lumbricoides and T. trichiura infections.

  3. Host specificity of Lepeophtheirus crassus (Wilson and Bere) (Copepoda: Caligidae) parasitic on the marlin sucker Remora osteochir (Cuvier) in the Atlantic Ocean.

    PubMed

    Ho, Ju-shey; Collete, Bruce B; Madinabeitia, Ione

    2006-10-01

    Three species of remoras--Remora brachyptera (Lowe), Remora osteochir (Cuvier), and Remora remora (Linnaeus)--were collected from 4 species of billfishes--Istiophorus platypterus (Shaw), Makaira nigricans Lacepéde, Tetrapturus albidus Poey, and Tetrapturus pfluegeri Robins and de Sylva--on board a Japanese long-liner Shoyo Maru during her cruise in 2002 across the Atlantic. However, only the marlin sucker (R. osteochir) was found to carry a parasitic copepod, Lepeophtheirus crassus (Wilson and Bere, 1936). Although 12 species of parasitic copepods have been reported from billfishes around the world ocean, none of them is L. crassus. Thus, L. crassus is considered a parasite specific to the marlin sucker.

  4. Unaspis lansivora sp. n. (Hemiptera: Diaspididae), a new pest of Lansium domesticum (Meliaceae), and a key to Unaspis species.

    PubMed

    Watson, Gillian W

    2015-01-13

    Since 2004, an undescribed species of Unaspis (Hemiptera: Diaspididae) has become a damaging pest on Lansium domesticum Corrêa in the Philippines. Its attack on the leaves causes premature senescence and defoliation, resulting in the production of few, underdeveloped, sour fruit and sometimes killing the trees. The scale was misidentified initially as Lepidosaphes ulmi (Linnaeus) and then as Unaspis citri (Comstock), but further study indicated that it was an undescribed species of potential plant quarantine significance. The pest is described as U. lansivora sp. n. and an identification key to all 19 species of Unaspis is provided. Its distribution, host range and prospects for its biological control are discussed.

  5. Continuous osteological characters in the reconstruction of phylogenetic relationships of the six Euro-Mediterranean mullet species (Mugilidae).

    PubMed

    Antović, Ivanka

    2013-09-01

    Sixty-three continuous osteological characters (18 skull continuous characters and the total length of neurocranium, 45 continuous characters of 15 elements of the viscerodermal skeleton) were analyzed and included in the reconstruction of phylogenetic relationships of the six Euro-Mediterranean mullet species from the South Adriatic Sea: Mugil cephalus Linnaeus, 1758; Liza saliens Risso, 1810; Liza aurata Risso, 1810; Liza ramada Risso, 1826; Chelon labrosus Risso, 1826 and Oedalechilus labeo Cuvier, 1829. The study reveals that Sphyraenidae was separated clearly from Mugilidae, C. labrosus and three Liza species form a common cluster (L. ramada and L. saliens being the closest), while O. labeo and M. cephalus cluster together.

  6. Winter infestation of wild birds by ticks and chiggers (Acari: Ixodidae, Trombiculidae) in the Czech Republic.

    PubMed

    Literak, Ivan; Kocianova, Elena; Dusbabek, Frantisek; Martinu, Jana; Podzemny, Petr; Sychra, Oldrich

    2007-11-01

    In winter months during 2003-2006, wild birds were captured and examined for ticks and chiggers at two sites near Brno, Czech Republic. In total, 1,362 birds, mostly passerines, were examined. The tick Ixodes arboricola Schulze et Schlottke, 1929 was found on 47 (3%) birds of six species. Ixodes ricinus Linnaeus, 1758 was found on 11 (1%) birds of five species. Larvae of chiggers Ascoschoengastia latyshevi (Schluger 1955) were found on 13 (1%) birds of six species. I. arboricola and A. latyshevi associated with hole-nesting birds can appear on birds rather frequently even during winter months. I. ricinus occurs on birds in winter sporadically.

  7. Checklist, distribution, and a new record of Nepomorphan water bugs (Hemiptera: Heteroptera) in northern Tunisia.

    PubMed

    Slimani, Noura; Moulet, Pierre; Chen, Ping-Ping; Nieser, Nico; Pluot-Sigwalt, Dominique; Boumaïza, Moncef; Guilbert, Eric

    2015-07-03

    We report on the results of a survey of the Nepomorpha of northern Tunisia, and list twenty-three species belonging to twelve genera and seven families: Nepidae, Ochteridae, Corixidae, Micronectidae, Naucoridae, Notonectidae, and Pleidae. These records are based on intensive field surveys during the year 2013 and examination of the entomological collections of the National Museum Natural History of Paris. Ranatra linearis (Linnaeus, 1758) is recorded for the first time from Tunisia. The occurrence of Sigara (Halicorixa) stagnalis stagnalis (Leach, 1817) in Tunisia is confirmed. A preliminary checklist of the Nepomorpha of Northern Tunisia and updated distribution maps for all species treated are provided for further studies.

  8. A survey of the epibiota of Eretmochelys imbricata (Testudines: Cheloniidae) of Mona Island, Puerto Rico.

    PubMed

    Schärer, Michelle T

    2003-06-01

    Epibiotic organisms inhabiting non-nesting hawksbill sea turtles, Eretmochelys imbricata (Linnaeus, 1766), are described from Mona and Monito Islands, Puerto Rico. Epibiont samples from 105 turtles of shallow (< 40 m) water foraging habitats were collected and identified to the lowest possible taxon. This epibiotic assemblage consisting of at least 4 algal functional groups and 12 animal phyla represents the greatest phylogenetic diversity for marine turtle epibiota. Six groups are considered new reports for marine turtles. Most epibiont colonization was found on posterior marginal scutes and under overlapping scutes. Ecological attributes of epibiota and their symbiosis with E. imbricata provide a tool to understand basi and epibiont populations.

  9. Using dogs for tiger conservation and research.

    PubMed

    Kerley, Linda L

    2010-12-01

    This paper is a review of the history, development and efficacy of using dogs in wildlife studies and considers the use of dogs in the research and conservation of wild tigers (Panthera tigris Linnaeus, 1758). Using scat detection dogs, scent-matching dogs, law enforcement detection dogs and protection dogs are proven methods that can be effectively used on tigers. These methods all take advantage of the dog's extremely evolved sense of smell that allows them to detect animals or animal byproducts (often the focus of tiger studies). Dogs can be trained to communicate this information to their handlers. © 2010 ISZS, Blackwell Publishing and IOZ/CAS.

  10. Neurohormonal changes associated with ritualized combat and the formation of a reproductive hierarchy in the ant Harpegnathos saltator

    USDA-ARS?s Scientific Manuscript database

    Dominance rank in animal societies is correlated with changes in both reproductive physiology and behavior. In some social insects, dominance status is used to determine a reproductive division of labor, where a few colony members reproduce while most remain functionally sterile. Changes in reproduc...

  11. The skull roof tracks the brain during the evolution and development of reptiles including birds.

    PubMed

    Fabbri, Matteo; Mongiardino Koch, Nicolás; Pritchard, Adam C; Hanson, Michael; Hoffman, Eva; Bever, Gabriel S; Balanoff, Amy M; Morris, Zachary S; Field, Daniel J; Camacho, Jasmin; Rowe, Timothy B; Norell, Mark A; Smith, Roger M; Abzhanov, Arhat; Bhullar, Bhart-Anjan S

    2017-10-01

    Major transformations in brain size and proportions, such as the enlargement of the brain during the evolution of birds, are accompanied by profound modifications to the skull roof. However, the hypothesis of concerted evolution of shape between brain and skull roof over major phylogenetic transitions, and in particular of an ontogenetic relationship between specific regions of the brain and the skull roof, has never been formally tested. We performed 3D morphometric analyses to examine the deep history of brain and skull-roof morphology in Reptilia, focusing on changes during the well-documented transition from early reptiles through archosauromorphs, including nonavian dinosaurs, to birds. Non-avialan taxa cluster tightly together in morphospace, whereas Archaeopteryx and crown birds occupy a separate region. There is a one-to-one correspondence between the forebrain and frontal bone and the midbrain and parietal bone. Furthermore, the position of the forebrain-midbrain boundary correlates significantly with the position of the frontoparietal suture across the phylogenetic breadth of Reptilia and during the ontogeny of individual taxa. Conservation of position and identity in the skull roof is apparent, and there is no support for previous hypotheses that the avian parietal is a transformed postparietal. The correlation and apparent developmental link between regions of the brain and bony skull elements are likely to be ancestral to Tetrapoda and may be fundamental to all of Osteichthyes, coeval with the origin of the dermatocranium.

  12. Allergenicity of bony and cartilaginous fish - molecular and immunological properties.

    PubMed

    Stephen, J N; Sharp, M F; Ruethers, T; Taki, A; Campbell, D E; Lopata, A L

    2017-03-01

    Allergy to bony fish is common and probably increasing world-wide. The major heat-stable pan-fish allergen, parvalbumin (PV), has been identified and characterized for numerous fish species. In contrast, there are very few reports of allergic reactions to cartilaginous fish despite widespread consumption. The molecular basis for this seemingly low clinical cross-reactivity between these two fish groups has not been elucidated. PV consists of two distinct protein lineages, α and β. The α-lineage of this protein is predominant in muscle tissue of cartilaginous fish (Chondrichthyes), while β-PV is abundant in muscle tissue of bony fish (Osteichthyes). The low incidence of allergic reactions to ingested rays and sharks is likely due to the lack of molecular similarity, resulting in reduced immunological cross-reactivity between the two PV lineages. Structurally and physiologically, both protein lineages are very similar; however, the amino acid homology is very low with 47-54%. Furthermore, PV from ancient fish species such as the coelacanth demonstrates 62% sequence homology to leopard shark α-PV and 70% to carp β-PV. This indicates the extent of conservation of the PV isoforms lineages across millennia. This review highlights prevalence data on fish allergy and sensitization to fish, and details the molecular diversity of the two protein lineages of the major fish allergen PV among different fish groups, emphasizing the immunological and clinical differences in allergenicity. © 2017 John Wiley & Sons Ltd.

  13. Plasma Levels of Nitrite and Nitrate in Early and Recent Classes of Fish

    PubMed Central

    Williams, Donna A; Flood, Mary H; Lewis, Debra A; Miller, Virginia M; Krause, William J

    2008-01-01

    The stable metabolite of nitric oxide in plasma is NOx, the sum of nitrite plus nitrate. Measures of plasma NOx may provide information about the nitric oxide tonus of the entire endothelium including capillary microvessels. Although data are available for mammalian species, plasma NOx measurements in early vertebrate species are scarce. The purpose of this study was to test the hypothesis that plasma NOx would be similar to the NOx in the water environment for fish in early classes (Agnatha and Chondrichthye) and would exceed water NOx levels in the known nitrite-sensitive fish (Osteichthye). Plasma samples were obtained from 18 species of adult fish (n = 167) and from their housing or natural water environment. NOx was measured by using chemiluminescence. Plasma NOx was detected in all species and ranged from 0.5 nmol/ml (skate) to 453.9 nmol/ml (shortnose gar). Average plasma NOx was significantly higher in sea lamprey than in Atlantic hagfish whereas that of little skate was 3-fold lower than in spiny dogfish shark. Plasma NOx differed significantly among early bony fish (paddlefish, pallid sturgeon, gar) yet was similar among modern bony fish, with the exception of rainbow trout. Plasma NOx reflected water NOx in only 2 species (hagfish and shark), and levels did not coincide with nitrite sensitivity. This study provides an expanded comparative view of plasma NOx levels across 3 groups of early fish. The data obtained suggest a nitric oxide system in early and modern fish. PMID:19004368

  14. Determination of toxic metals, trace and essentials, and macronutrients in Sarpa salpa and Chelon labrosus: risk assessment for the consumers.

    PubMed

    Afonso, Aridani; Gutiérrez, Angel J; Lozano, Gonzalo; González-Weller, Dailos; Rubio, Carmen; Caballero, José M; Hardisson, Arturo; Revert, Consuelo

    2017-04-01

    Due to increased environmental pollution, monitoring of contaminants in the environment and marine organisms is a fundamental tool for assessing the existence of risk from their consumption to human health. The levels of toxic heavy metals (Cd, Pb, and Al), trace and essential metals (B, Ba, Co, Cu, Cr, Fe, Li, Mn, Mo, Ni, Sr, V, and Zn), and macronutrients (Ca, K, Mg, Na) in two species of fish for human consumption were quantified in the present study. Eighty samples of muscle tissue and 80 samples of liver tissue belonging to two species of Osteichthyes fish; Sarpa salpa and Chelon labrosus were analyzed. The studied specimens were caught on the northern coast of Gran Canaria (Canary Islands) with fishing rods. As they caught from the shore, they are suitable samples for assessing the toxic levels of representative species caught by local amateur fishermen. The results show that both species are fit for human consumption since they have toxic levels of heavy metals (Cd, Pb, and Al) which are below the maximum established levels; however, the toxic levels of the liver samples are several orders of magnitude higher than the muscle samples, so we discourage their regular consumption. The risk assessment indicated that the two species of fish are safe for the average consumer; however, if the livers of these species are consumed, there could be risks because they exceed the PTWI for Pb and the TWI for Cd.

  15. Biostratigraphy and biochronology of the Monte Hermoso Formation (early Pliocene) at its type locality, Buenos Aires Province, Argentina

    NASA Astrophysics Data System (ADS)

    Tomassini, Rodrigo L.; Montalvo, Claudia I.; Deschamps, Cecilia M.; Manera, Teresa

    2013-12-01

    The Monte Hermoso Formation, cropping out at its type locality of Farola Monte Hermoso (Buenos Aires Province), is a classical fossiliferous unit of the South American Neogene, highlighted by the abundance and diversity of its vertebrate remains. However, its biostratigraphy and age have been largely debated, and numerous discrepancies and controversies have been stated. In this regard, the result of the analysis of new materials recovered from the different levels of this formation, following a strict control of stratigraphic provenance, is here reported. As well, the provenance of specimens of previous collections has been evaluated. The studied assemblage consists of Osteichthyes, Amphibia, Reptilia, Aves and Mammalia. These latter are the most numerous and belong to the Didelphimorphia, Polydolopimorphia, Rodentia, Notoungulata, Litopterna and Xenarthra. The recorded taxa suggest no important faunistic variations among the different levels of the Monte Hermoso Formation that would imply significant chronological differences, and hence, justify the recognition of two biostratigraphic units. The analysis of the first and last records as well as the taxa considered as exclusive, does not support the validity of the biozones of Trigodon gaudryi and Neocavia depressidens previously proposed. On this basis, a new scheme for the Monte Hermoso Formation at its type locality is proposed, including a new single biostratigraphic unit. This unit is the Eumysops laeviplicatus Range Zone, which represents the biostratigraphic base for the Montehermosan Stage/Age of the early Pliocene.

  16. Family-group names in Coleoptera (Insecta)

    PubMed Central

    Bouchard, Patrice; Bousquet, Yves; Davies, Anthony E.; Alonso-Zarazaga, Miguel A.; Lawrence, John F.; Lyal, Chris H. C.; Newton, Alfred F.; Reid, Chris A. M.; Schmitt, Michael; Ślipiński, S. Adam; Smith, Andrew B. T.

    2011-01-01

    Abstract We synthesize data on all known extant and fossil Coleoptera family-group names for the first time. A catalogue of 4887 family-group names (124 fossil, 4763 extant) based on 4707 distinct genera in Coleoptera is given. A total of 4492 names are available, 183 of which are permanently invalid because they are based on a preoccupied or a suppressed type genus. Names are listed in a classification framework. We recognize as valid 24 superfamilies, 211 families, 541 subfamilies, 1663 tribes and 740 subtribes. For each name, the original spelling, author, year of publication, page number, correct stem and type genus are included. The original spelling and availability of each name were checked from primary literature. A list of necessary changes due to Priority and Homonymy problems, and actions taken, is given. Current usage of names was conserved, whenever possible, to promote stability of the classification. New synonymies (family-group names followed by genus-group names): Agronomina Gistel, 1848 syn. nov. of Amarina Zimmermann, 1832 (Carabidae), Hylepnigalioini Gistel, 1856 syn. nov. of Melandryini Leach, 1815 (Melandryidae), Polycystophoridae Gistel, 1856 syn. nov. of Malachiinae Fleming, 1821 (Melyridae), Sclerasteinae Gistel, 1856 syn. nov. of Ptilininae Shuckard, 1839 (Ptinidae), Phloeonomini Ádám, 2001 syn. nov. of Omaliini MacLeay, 1825 (Staphylinidae), Sepedophilini Ádám, 2001 syn. nov. of Tachyporini MacLeay, 1825 (Staphylinidae), Phibalini Gistel, 1856 syn. nov. of Cteniopodini Solier, 1835 (Tenebrionidae); Agronoma Gistel 1848 (type species Carabus familiaris Duftschmid, 1812, designated herein) syn. nov. of Amara Bonelli, 1810 (Carabidae), Hylepnigalio Gistel, 1856 (type species Chrysomela caraboides Linnaeus, 1760, by monotypy) syn. nov. of Melandrya Fabricius, 1801 (Melandryidae), Polycystophorus Gistel, 1856 (type species Cantharis aeneus Linnaeus, 1758, designated herein) syn. nov. of Malachius Fabricius, 1775 (Melyridae), Sclerastes

  17. Electric field measurements during the blowing snow in a cryogenic wind tunnel by a non-contact voltmeter

    NASA Astrophysics Data System (ADS)

    Sato, A.; Omiya, S.

    2011-12-01

    It is known that the average atmospheric electric field is +100V/m in fair weather (positive electric field vector points downward). An increase of atmospheric electric field is reported when the blowing snow occurred. This phenomenon is mainly explained by the fact that the blowing snow particles have negative charge in average. It is suggested that an electrostatic force, given by the product of the electric field and the charge of the particle, may influence the particle trajectory and change those movements, saltation and suspension. The purpose of this experiment is to clarify the characteristics of the electric field during blowing snow event. Experiments were carried out in the cryogenic wind tunnel of Snow and Ice Research Center, NIED. A non-contact voltmeter was used to measure the electric field. An artificial blowing snow was generated by a snow particle supply machine. The rolling brushes of the machine scratch the snow surface and supply snow particles into the airflow. This machine made it possible to supply the snow particles at an arbitrary rate. This experiment was conducted in the following experimental conditions; wind speed of 5 to 7 m/s (3 patterns), supply snow quantity of 8.7 to 34.9 g/m/s (4 patterns), air temperature of -10 degree Celsius, fetch of 10 m and hard snow surface. Measured electric field was all negative, which is opposite direction to the previous measurements. This means that the blowing snow particles had positive charges. The negative electric field tended to increase with increase of the wind speed and the mass flux. These results can be explained from the previous experiment by Omiya and Sato (2010). The snow particles gain positive charges by the friction with the rolling brush which is made from polypropylene, however the particles accumulate negative charges gradually with increase of the collisions to the snow surface. Probably, the positive charges might have remained on the snow particles that had passed over the

  18. Correlations between Cassini VIMS spectra and RADAR SAR images: Implications for Titan's surface composition and the character of the Huygens Probe Landing Site

    USGS Publications Warehouse

    Soderblom, L.A.; Kirk, R.L.; Lunine, J.I.; Anderson, J.A.; Baines, K.H.; Barnes, J.W.; Barrett, J.M.; Brown, R.H.; Buratti, B.J.; Clark, R.N.; Cruikshank, D.P.; Elachi, C.; Janssen, M.A.; Jaumann, R.; Karkoschka, E.; Le Mouélic, Stéphane; Lopes, R.M.; Lorenz, R.D.; McCord, T.B.; Nicholson, P.D.; Radebaugh, J.; Rizk, B.; Sotin, Christophe; Stofan, E.R.; Sucharski, T.L.; Tomasko, M.G.; Wall, S.D.

    2007-01-01

    Titan's vast equatorial fields of RADAR-dark longitudinal dunes seen in Cassini RADAR synthetic aperture images correlate with one of two dark surface units discriminated as "brown" and "blue" in Visible and Infrared Mapping Spectrometer (VIMS) color composites of short-wavelength infrared spectral cubes (RGB as 2.0, 1.6, 1.3 ??m). In such composites bluer materials exhibit higher reflectance at 1.3 ??m and lower at 1.6 and 2.0 ??m. The dark brown unit is highly correlated with the RADAR-dark dunes. The dark brown unit shows less evidence of water ice suggesting that the saltating grains of the dunes are largely composed of hydrocarbons and/or nitriles. In general, the bright units also show less evidence of absorption due to water ice and are inferred to consist of deposits of bright fine precipitating tholin aerosol dust. Some set of chemical/mechanical processes may be converting the bright fine-grained aerosol deposits into the dark saltating hydrocarbon and/or nitrile grains. Alternatively the dark dune materials may be derived from a different type of air aerosol photochemical product than are the bright materials. In our model, both the bright aerosol and dark hydrocarbon dune deposits mantle the VIMS dark blue water ice-rich substrate. We postulate that the bright mantles are effectively invisible (transparent) in RADAR synthetic aperture radar (SAR) images leading to lack of correlation in the RADAR images with optically bright mantling units. RADAR images mostly show only dark dunes and the water ice substrate that varies in roughness, fracturing, and porosity. If the rate of deposition of bright aerosol is 0.001-0.01 ??m/yr, the surface would be coated (to optical instruments) in hundreds-to-thousands of years unless cleansing processes are active. The dark dunes must be mobile on this very short timescale to prevent the accumulation of bright coatings. Huygens landed in a region of the VIMS bright and dark blue materials and about 30 km south of the

  19. Analysis of spawning behavior, habitat, and season of the federally threatened Etheostoma scotti, Cherokee darter (Osteichthyes: Percidae)

    USGS Publications Warehouse

    Storey, C.M.; Porter, B.A.; Freeman, Mary C.; Freeman, B.J.

    2006-01-01

    Etheostoma scotti (Cherokee darter) is a member of the subgenus Ulocentra and a federally threatened endemic to the Etowah River system, GA. Field observations of spawning behavior of the Cherokee darter were made at five stream sites to identify spawning season and habitat over two field seasons. Cherokee darters primarily spawn in pool habitats between mid-March and early June, at temperatures between 11 and 18 ?C. Egg deposition was typically on large gravel substrate, but ranged from gravel to bedrock in size and included woody debris. Spawning occurred in a variety of depths (0.09-0.59 m) and velocities (0-0.68 m/s).

  20. Sheet Flows, Avalanches, and Dune Evolution on Earth and Mars

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This investigation is a collaboration between researchers at Cornell University, the University of Florida, and the University of Rennes 1, France. Flow modeling at Cornell University focused on mechanisms for the suspension and transport of wind-blown sand that are important in both terrestrial and Martian environments. These mechanisms include the saltation (or jumping) of grains, collisions between grains, and the interaction of grains with the velocity fluctuations of the turbulent wind. Of particular interest are sheet flows; these are relatively thin, highly concentrated regions of grains flowing near the ground under the influence of a strong turbulent wind. In them, the grains are suspended by interparticle collisions. Sheet flows may be relatively rare events, but they have the capacity to move great amounts of sand. In order to describe sheet flows, a turbulent mixture theory was formulated for particles in a fluid in which fluctuations in the volume fiaction of the particles take place on the scale of the turbulent eddies. Ensemble averaged equations for particle and fluid mass, momentum, and energy and fluid rate of dissipation were expressed in terms of Farve (concentration) averaged velocities and the associated velocity fluctuations. Correlations that describe the turbulent suspension of particles and dissipation of turbulent energy of both phases due to fluid particle interactions were modeled and boundary conditions at the bed and at the upper surface of the collisional flow were formulated. The boundary conditions at the upper surface were tested in a numerical simulation developed at the University of Florida. Steady and unsteady solutions for steady and unsteady fully-developed flows were obtained over a range of wind speeds fiom the lowest for which collisional between particles occurred to at which turbulent suspension is found to dominate collisional suspension. Below the value of the wind speed at which collisions between particles were

  1. Treerunners, cryptic lizards of the Plica plica group (Squamata, Sauria, Tropiduridae) of northern South America

    PubMed Central

    Murphy, John C.; Jowers, Michael J.

    2013-01-01

    Abstract The arboreal, Neotropical lizard Plica plica (Linnaeus, 1758) has been long considered a widespread species with a distribution east of the Andes. A preliminary examination of 101 specimens from about 28 locations mostly north of the Amazon suggests that Plica plica is a cryptic species complex with taxa that can be distinguished on the basis of the number of scale rows at mid-body; the arrangement, shape and ornamentation of scales on the snout; the number of lamellae on the fourth toe; the number of subocular plates; as well as other commonly used external morphological traits. The allopatric species discussed here are concordant with northern South American geography. Plica plica (Linnaeus, 1758) is associated with the Guiana Shield (Suriname, Guyana and Venezuela). A second species, P. caribeana sp. n. is associated with the Caribbean Coastal Range of Venezuela including Trinidad and Tobago. A third, distinctive species, P. rayi sp. n. is associated with the middle Orinoco at the eastern edge of the Guiana Shield. Two other species, P. kathleenae sp. n. and P. medemi sp. n., each based upon a single specimen, one from the Sierra Acarai Mountains of Guyana, and the other from southern Meta, Colombia are described. In addition to morphological analyses, we sequenced 12S and 16S rDNA gene fragments from one Plica plica from Trinidad to assess its relationship and taxonomy to other mainland Plica cf. plica. The results suggest Plica caribeana sp. n. likely diverged prior to the separation of Trinidad from northern Venezuela. Isolation in the Caribbean Coastal Range during its rapid uplift in the late Miocene, combined with a marine incursion into northern Venezuela may have contributed to their genetic divergence from other populations. PMID:24363569

  2. The occurrence of metacercariae of Petasiger (Digenea: Echinostomatidae) in an unusual site, within the lateral line scales of cyprinid fishes.

    PubMed

    Molnar, Kalman; Gibson, David I; Cech, Gabor; Papp, Melitta; Deak-Paulus, Petra; Juhasz, Lajos; Toth, Norbert; Szekely, Csaba

    2015-01-01

    During a regular veterinary inspection of fishes from Lake Balaton, Hungary, echinostomatid metacercariae (Digenea), with collar spines characteristic of species of the genera Petasiger Dietz, 1909 and Paryphostomum Dietz, 1909, were found in the lateral line scales of a roach Rutilus rutilus (Linnaeus), an apparently unique site. In a subsequent examination of 586 fishes from 20 different species, similar infections were found in 11 species. The infection was virtually restricted to the lateral line scales, other scales being infected only incidentally. These encysted metacercariae had 27 collar spines, including eight larger angle spines and 19 smaller dorsal spines arranged in two rows. Two types of metacercarial cyst were found. One type had a cyst diameter of 138-171 µm × 105-120 µm and three central dorsal spines that were larger than the remainder and tended to resemble the angle spines. The second type of metacercarial cyst had a diameter of 128-157 µm × 105-115 µm and all 19 dorsal spines of the metacercaria were of a similar size. ITS sequences of the second type of metacercaria exhibited a 100% similarity to sequences of two adult Petasiger phalacrocoracis (Yamaguti, 1939) specimens collected from the gut of Phalacrocorax carbo (Linnaeus) in Hungary and to P. phalacrocoracis deposited in the GenBank database. Sequences obtained from two metacercariae of the first type showed a 2.8-2.9 % difference from sequences of the second type of metacercaria and from those of adult specimens of P. phalacrocoracis from cormorants. Based on these results, the second type metacercaria is considered to be a larval stage of P. phalacrocoracis, but the identity of the first type is uncertain. The unusual location of these metacercariae in the lateral line scales is discussed in relation to their transmission.

  3. Differential repetitive DNA composition in the centromeric region of chromosomes of Amazonian lizard species in the family Teiidae.

    PubMed

    Carvalho, Natalia D M; Carmo, Edson; Neves, Rogerio O; Schneider, Carlos Henrique; Gross, Maria Claudia

    2016-01-01

    Differences in heterochromatin distribution patterns and its composition were observed in Amazonian teiid species. Studies have shown repetitive DNA harbors heterochromatic blocks which are located in centromeric and telomeric regions in Ameiva ameiva (Linnaeus, 1758), Kentropyx calcarata (Spix, 1825), Kentropyx pelviceps (Cope, 1868), and Tupinambis teguixin (Linnaeus, 1758). In Cnemidophorus sp.1, repetitive DNA has multiple signals along all chromosomes. The aim of this study was to characterize moderately and highly repetitive DNA sequences by C ot1-DNA from Ameiva ameiva and Cnemidophorus sp.1 genomes through cloning and DNA sequencing, as well as mapping them chromosomally to better understand its organization and genome dynamics. The results of sequencing of DNA libraries obtained by C ot1-DNA showed that different microsatellites, transposons, retrotransposons, and some gene families also comprise the fraction of repetitive DNA in the teiid species. FISH using C ot1-DNA probes isolated from both Ameiva ameiva and Cnemidophorus sp.1 showed these sequences mainly located in heterochromatic centromeric, and telomeric regions in Ameiva ameiva, Kentropyx calcarata, Kentropyx pelviceps, and Tupinambis teguixin chromosomes, indicating they play structural and functional roles in the genome of these species. In Cnemidophorus sp.1, C ot1-DNA probe isolated from Ameiva ameiva had multiple interstitial signals on chromosomes, whereas mapping of C ot1-DNA isolated from the Ameiva ameiva and Cnemidophorus sp.1 highlighted centromeric regions of some chromosomes. Thus, the data obtained showed that many repetitive DNA classes are part of the genome of Ameiva ameiva, Cnemidophorus sp.1, Kentroyx calcarata, Kentropyx pelviceps, and Tupinambis teguixin, and these sequences are shared among the analyzed teiid species, but they were not always allocated at the same chromosome position.

  4. Spatial and temporal patterns of subtidal and intertidal crabs excursions

    NASA Astrophysics Data System (ADS)

    Silva, A. C. F.; Boaventura, D. M.; Thompson, R. C.; Hawkins, S. J.

    2014-01-01

    Highly mobile predators such as fish and crabs are known to migrate from the subtidal zone to forage in the intertidal zone at high-tide. The extent and variation of these habitat linking movements along the vertical shore gradient have not been examined before for several species simultaneously, hence not accounting for species interactions. Here, the foraging excursions of Carcinus maenas (L.), Necora puber (Linnaeus, 1767) and Cancer pagurus (Linnaeus, 1758) were assessed in a one-year mark-recapture study on two replicated rocky shores in southwest U.K. A comparison between the abundance of individuals present on the shore at high-tide with those present in refuges exposed at low-tide indicated considerable intertidal migration by all species, showing strong linkage between subtidal and intertidal habitats. Estimates of population size based on recapture of marked individuals indicated that an average of ~ 4000 individuals combined for the three crab species, can be present on the shore during one tidal cycle. There was also a high fidelity of individuals and species to particular shore levels. Underlying mechanisms for these spatial patterns such as prey availability and agonistic interactions are discussed. Survival rates were estimated using the Cormack-Jolly-Seber model from multi-recapture analysis and found to be considerably high with a minimum of 30% for all species. Growth rates were found to vary intraspecifically with size and between seasons. Understanding the temporal and spatial variations in predation pressure by crabs on rocky shores is dependent on knowing who, when and how many of these commercially important crab species depend on intertidal foraging. Previous studies have shown that the diet of these species is strongly based on intertidal prey including key species such as limpets; hence intertidal crab migration could be associated with considerable impacts on intertidal assemblages.

  5. Repeatability, Reproducibility, Separative Power and Subjectivity of Different Fish Morphometric Analysis Methods

    PubMed Central

    Takács, Péter

    2016-01-01

    We compared the repeatability, reproducibility (intra- and inter-measurer similarity), separative power and subjectivity (measurer effect on results) of four morphometric methods frequently used in ichthyological research, the “traditional” caliper-based (TRA) and truss-network (TRU) distance methods and two geometric methods that compare landmark coordinates on the body (GMB) and scales (GMS). In each case, measurements were performed three times by three measurers on the same specimen of three common cyprinid species (roach Rutilus rutilus (Linnaeus, 1758), bleak Alburnus alburnus (Linnaeus, 1758) and Prussian carp Carassius gibelio (Bloch, 1782)) collected from three closely-situated sites in the Lake Balaton catchment (Hungary) in 2014. TRA measurements were made on conserved specimens using a digital caliper, while TRU, GMB and GMS measurements were undertaken on digital images of the bodies and scales. In most cases, intra-measurer repeatability was similar. While all four methods were able to differentiate the source populations, significant differences were observed in their repeatability, reproducibility and subjectivity. GMB displayed highest overall repeatability and reproducibility and was least burdened by measurer effect. While GMS showed similar repeatability to GMB when fish scales had a characteristic shape, it showed significantly lower reproducability (compared with its repeatability) for each species than the other methods. TRU showed similar repeatability as the GMS. TRA was the least applicable method as measurements were obtained from the fish itself, resulting in poor repeatability and reproducibility. Although all four methods showed some degree of subjectivity, TRA was the only method where population-level detachment was entirely overwritten by measurer effect. Based on these results, we recommend a) avoidance of aggregating different measurer’s datasets when using TRA and GMS methods; and b) use of image-based methods for

  6. Horizontal transmission of the ectoparasite Gyrodactylus arcuatus (Monogenea: Gyrodactylidae) to the next generation of the three-spined stickleback Gasterosteus aculeatus.

    PubMed

    Lumme, Jaakko; Zietara, Marek S

    2018-04-19

    In the parthenogenetic monogeneans of the genus Gyrodactylus Nordmann, 1832, the genetic diversity within or between hosts is determined by the relative roles of lateral transmission and clonal propagation. Clonality and limited transmission lead to high-amplitude metapopulation dynamics and strong genetic drift. In Baltic populations of the three-spined stickleback Gasterosteus aculeatus Linnaeus, the local mitochondrial diversity of Gyrodactylus arcuatus Bychowsky, 1933 is very high, and spatial differentiation weak. To understand the transmission dynamics in a single location, the transmission of the parasite from adults to next generation sticklebacks was investigated in a northern Baltic brackish water location. By sequencing 777 nt of cox1, as many as 38 separate mitochondrial haplotypes were identified. In August, the intensity of gyrodactylid infection on adult hosts was high, the haplotype diversity (h) was extreme and differentiation between fish was negligible (total h = 0.926, mean h = 0.938). In October, only 46% of the juvenile sticklebacks carried G. arcuatus. The number of parasites per young fish followed a Poisson distribution 0.92 ± 1.04 (mean ± SD) on October 2, and was clearly overdispersed 2.38 ± 5.00 on October 25. The total haplotype diversity of parasites on juveniles was nearly as high as in adults (h = 0.916), but the mean per fish was only h = 0.364 (F ST = 0.60), due to low intensity of infection and rapid clonal propagation of early arrivals. The initial first come first served advantage of the first gyrodactylid colonisers will be lost during the host adulthood via continuous transmission. Nesting and polygamy are suggested as factors maintaining the high genetic diversity of the parasite population. The transmission dynamics and, consequently, the population structure of Baltic G. arcuatus is fundamentally different from that of G. salaris Malmberg, 1957, on the Baltic salmon Salmo salar Linnaeus.

  7. Ecology of the Wood-boring Bivalve Martesia striata (Pholadidae) in Indian Waters

    NASA Astrophysics Data System (ADS)

    Yennawar, P. L.; Thakur, N. L.; Anil, A. C.; Venkat, K.; Wagh, A. B.

    1999-08-01

    Martesia striata (Linnaeus) is one of the dominant wood-boring organisms found in Indian waters. Incidence of this organism in the Zuari estuary (Goa) was evaluated by exposing wooden panels (Mangifera indica) to the marine environment between January 1996 and January 1997. Effects of salinity variation on embryonic and larval development were evaluated (salinity 0, 10, 20, 30, 35, 40 and 50, temperature 25 °C) and maximum metamorphic success was observed at 30 salinity. Results of the rearing experiments, destruction pattern of wood in the environment and reproductive biology indicate that although recruitment is halted during the monsoon, adults survive and become reproductively mature in the following post-monsoon, leading to increased recruitment during pre-monsoon months.

  8. Occurrence of Thelazia callipaeda and Toxocara cati in an imported European lynx (Lynx lynx) in Japan.

    PubMed

    El-Dakhly, Khaled; Abo El-Hadid, Shawky; Shimizu, Hirofumi; El-Nahass, Shaymaa; Murai, Atsuko; Sakai, Hiroki; Yanai, Tokuma

    2012-09-01

    A necropsy was performed on an adult European lynx, Lynx lynx (Linnaeus, 1758), held in captivity until its death, to determine level of parasitism. Examination of the eyes revealed the oriental eyeworm, Thelazia callipaeda, in the conjunctival sac and the third eyelid of both eyes. The species was confirmed by location and morphology. Intact worms were fixed, mounted, and identified. Examination of the alimentary tract revealed the common ascaroid nematode, Toxocara cati. Species was confirmed by the arrow-like anterior end. One hundred and forty-one adult worms were collected. The presence of these nematodes indicated the importance of eliminating the contact of zoo animals with Amiota spp. vectors and to prevent contamination with the infective T. cati eggs.

  9. The systematic status of the Italian wolf Canis lupus

    USGS Publications Warehouse

    Nowak, Ronald M.; Federoff, Nicholas E.

    2002-01-01

    In the past, the gray wolf Canis lupus Linnaeus, 1758, has been recognized in Italy as either the subspecies lupus or italicus. It has also been postulated that this population has undergone introgression from the domestic dog Canis familiaris. In order to clarify these issues, multistatistical analyses were made of 10 skull measurements of 34 full grown male wolves from the Italian Peninsula, 91 other male Eurasian wolves, and 20 domestic dogs. The analyses, together with other morphological evidence and prior genetic research, support recognition of the Italian wolf as a separate subspecies, Canis lupus italicus. The same evidence indicates that the subspecies has not been affected through hybridization with the domestic dog.

  10. Checklist of host associations of European bat flies (Diptera: Nycteribiidae, Streblidae).

    PubMed

    Szentiványi, Tamara; Estók, Péter; Földvári, Mihály

    2016-12-05

    Bat flies are obligate blood-sucking ectoparasites of bats. They are divided into two families: Nycteribiidae and Streblidae. Europe has 17 species of bat flies and 45 species of bats (Mammalia: Chiroptera). This checklist is based on both published records and our own field data and provides updated information on all associations between bat flies and their hosts in Europe. The host-parasite association between Basilia italica Theodor and Plecotus auritus (Linnaeus) is reported for the first time. Moreover, our records of B. italica on Myotis alcathoe Helversen & Heller, B. nana Theodor & Moscona on Plecotus auritus, Nycteribia kolenatii Theodor & Moscona on M. bechsteinii (Kuhl) and Penicillidia dufourii (Westwood) on M. daubentonii (Kuhl) represent new host associations for Hungary.

  11. Review of the fish-parasitic genus Cymothoa Fabricius, 1793 (Crustacea: Isopoda: Cymothoidae) from Australia.

    PubMed

    Martin, Melissa B; Bruce, Niel L; Nowak, Barbara F

    2016-06-03

    The genus Cymothoa Fabricius, 1793 is revised for Australian waters. Cymothoa hermani Hadfield, Bruce & Smit, 2011, previously known from Tanzania on the host Selar crumenophthalmus (Bloch, 1793) is new to Australian waters. Cymothoa carangi Avdeev, 1979; Cymothoa epimerica Avdeev, 1979; Cymothoa parupenei Avdeev, 1979; Cymothoa propria Avdeev, 1979; Cymothoa rotunda Avdeev, 1979 and Cymothoa pulchrum Lanchester, 1902 are redescribed. Cymothoa curta Schioedte & Meinert, 1884, first described from the host Anableps anableps (Linnaeus, 1758); and Cymothoa plebeia Schioedte & Meinert, 1884, first described from Cape Verde; are redescribed and excluded from the Australian fauna. Cymothoa limbata Schioedte & Meinert, 1884 is placed into junior synonymy with Cymothoa eremita (Brünnich, 1783). A key to the Australian species of Cymothoa is presented.

  12. Dioctophyme renale (Nematoda, Dioctophymatidae) infection in the crab-eating fox (Cerdocyon thous) from Brazil.

    PubMed

    Ribeiro, Carlos Torres; Verocai, Guilherme Gomes; Tavares, Luiz Eduardo Roland

    2009-01-01

    The purpose of this study is to report the first case of parasitism by the giant kidney worm, Dioctophyme renale (Goeze, 1782), in the crab-eating fox, Cerdocyon thous (Linnaeus, 1766), in Brazil. A debilitated adult male fox was taken to the Screening Center for Wild Animals in Rio de Janero (CETAS/RJ) and eventually died of an unknown cause. During necropsy, a brownish-red nematode, 28.9 cm long, was found in the peritoneal cavity. The worm was identified as a male D. renale. This study reports the first case of dioctophymatosis in the crab-eating fox, enlarging the range of wild definitive host species infected by the giant kidney worm in the Neotropical region.

  13. Redescription of Mehdiella microstoma and description of Mehdiella petterae sp. n., with a new definition of the genus Mehdiella Seurat, 1918 (Nematoda: Pharyngodonidae).

    PubMed

    Bouamer, S; Morand, S; Bourgat, R

    2001-01-01

    The generic diagnosis of Mehdiella Seurat, 1918 is emended based on study and redescription of Mehdiella microstoma (Drasche, 1884) from the caecum of Testudo graeca Linnaeus, 1758 collected in Settat, Morocco and on study and description of a new species, Mehdiella petterae sp. n., from the large intestine of Testudo hermanni (Gmelin, 1789) collected in Catalonia, Spain. Scanning electron microscopy (SEM) studies revealed substantial differences in the structure of the mouth and the caudal end, and made possible to differentiate the new species from the others. SEM studies showed the real and sound characteristics of the genus Mehdiella, namely number of anal papillae 2 instead of 3, post-anal papillae pedunculate or sessile instead sessile.

  14. Diagnostic Cytochrome b gene profiles for the identification of paca (Cuniculus paca) bushmeat: implications for the monitoring of illegal hunting and wildlife trade.

    PubMed

    Silva-Neto, A A; Ferreira, P B; Torres, R A; Texeira, R H F; Duarte, J M B; Barbosa, A C; Vargas, R C; Garcia, J E

    2016-02-01

    Paca (Cuniculus paca Linnaeus, 1766) is the second largest rodent found in Brazil. The quality of the meat and a long tradition of hunting have contributed to the decline of the natural populations of this species. Hunting of paca is strictly prohibited in Brazil, but in spite of this restriction, no forensic tools are available for the identification of the meat. We describe an efficient method, based on single nucleotide polymorphisms of the cytochrome b gene, that can be used to differentiate biological material derived from paca from those of domestic species commonly used as sources of meat. The identification of the presence of C. paca in the samples was 100% reliable.

  15. Phospholipid fatty acid composition of Gorgonia mariae and Gorgonia ventalina.

    PubMed

    Carballeira, Néstor M; Miranda, Carlos; Rodríguez, Abimael D

    2002-01-01

    The phospholipid fatty acid composition of the Caribbean gorgonians Gorgonia mariae (Bayer) and Gorgonia ventalina (Linnaeus) is described for the first time. The main phospholipids identified were phosphatidylethanolamine, phosphatidylcholine, and phosphatidylserine. The main fatty acids were 14:0, 16:0, 18:3(n-6), 18:4(n-3), 18:2(n-6), 20:4(n-6), 22:6(n-3), and 24:5(n-6). In both G. mariae and G. ventalina n-6 polyunsaturated fatty acids predominated over the n-3 family. In addition, the 7-methyl-6(E)-hexadecenoic acid was identified in both gorgonians. The occurrence of tetracosapolyenoic fatty acids in the genus Gorgonia is also reported for the first time.

  16. New Coleoptera records from New Brunswick, Canada: Cerambycidae.

    PubMed

    Webster, Reginald P; Sweeney, Jon D; Demerchant, Ian; Silk, Peter J; Mayo, Peter

    2012-01-01

    Five species of Cerambycidae, Acmaeops discoideus (Haldeman), Anelaphus villosus (Fabricius), Phymatodes species (CNC sp. n. #1), Sarosesthes fulminans (Fabricius), and Urgleptus signatus (LeConte) are newly recorded for New Brunswick, Canada. All but Acmaeops villosus are new to the Maritime provinces. Phymatodes testaceus (Linnaeus) is removed from the faunal list of the province as a result of mislabeled specimens, records of Phymatodes maculicollis LeConte are presented confirming the presence of this species in New Brunswick, and the first recent records ofNeospondylis upiformis (Mannerheim) are presented. Additional records are given for the recently recorded Phymatodes aereus (Newman), indicating a wider distribution in the province. Collection data, habitat data, and distribution maps are presented for each species.

  17. Rash caused by Oryctes nasicornis.

    PubMed

    Veraldi, Stefano; Fanoni, Daniele; Nazzaro, Gianluca

    2016-02-01

    We report a case of rash caused by crushing of a male of Oryctes nasicornis (Linnaeus 1758) (Coleoptera, "http:// it. wikipedia. org/ wiki/ Scarabaeidae" \\o "Scarabaeidae" Scarabaeidae), popularly known as "European rhinoceros beetle", on the skin of an Italian tourist who developed the reaction during a trip to Turkey. The rash appeared one hour after the crushing of the insect on the skin. The patient was observed one day later, when she returned to Italy. To our knowledge, no similar cases have been reported in the literature. © International Society of Travel Medicine, 2016. All rights reserved. Published by Oxford University Press. For permissions, please e-mail: journals.permissions@oup.com.

  18. Cuticular Biominerals of the Terrestrial Crustacean Oniscus asellus (Isopoda, Linnaeus 1758)

    NASA Astrophysics Data System (ADS)

    Mergelsberg, S. T.; Mukhopadhyay, B.; Dove, P. M.

    2013-12-01

    Biomineralization is a phenomenon observed in many eukaryotic organisms and evidence suggests this process began relatively early in the evolution of multicellular life (Marin F et al. 1996). Crustaceans form a large fraction of all eukaryotic biomineralizers by incorporating calcium carbonate (CaCO3) into their cuticle. Terrestrial species are challenged in their production of CaCO3 by the absence of calcium-rich waters. To cope with this limitation, the terrestrial crustacean Oniscus asellus recycles up to 80% (Auzou G 1953) of its total calcium during the molting process. This feat is accomplished by separate molting of the front and back cuticle, with temporary storage of the calcium carbonate as amorphous calcium carbonate (ACC) in the front half (Ziegler A 1997). These processes infer a highly efficient and regulated mechanism for biomineralization that is most likely orchestrated by a myriad of proteins (Ziegler A et al. 2012). Until recently, investigations of biomineralization were largely directed toward understanding morphology and large-scale chemistry of the minerals, ignoring the mechanistic roles of biomacromolecules in mineralization processes. More recent work suggests a high involvement of these compounds on the formation of biominerals and, in some cases, the specific polymorphs thereof (Keene EC et al. 2010). This study focuses on identifying the components of the biological mineralization matrix at each stage of the process. Using chemical demineralization of the stored ACC, all biomacromolecules can be separated and purified for subsequent analysis by MALDI-TOF mass spectrometry. To link the localized biochemistry more intimately to the polymorph of calcium carbonate that forms in the animal, the inorganic phase (';the mineral') will be monitored at each life stage using XRD and TEM. This analysis will reveal the organic components of a very precise biomineralization mechanism and may shed insight on its evolutionary origin. References: Marin F, Westbroek P et al., 1996, Proc Nat Acad Sci 93:1554-1559 Auzou G, 1953, L Ann Sci Nat 15:71-98 Ziegler A, 1997, Zoomorphology 117:181-187 Ziegler A et al., 2012, Cryst Growth Des 12:646-655 Keene EC et al., 2010, Cryst Growth Des 10:1383-1389

  19. NOTES ON THE EMBRYONIC PERIOD OF THE PINFISH LAGODON RHOMBOIDES (LINNAEUS)

    EPA Science Inventory

    Adult pinfish, Lagodon rhomboides, were collected during September and October, 1974 and 1975. Following a minimum of one week holding period, females were initially injected with 200 IU human chorionic gonadotropin and injected with 400 IU every second day thereafter until matur...

  20. Adulticidal activity of some Malaysian plant extracts against Aedes aegypti Linnaeus.

    PubMed

    Hidayatulfathi, O; Sallehuddin, S; Ibrahim, J

    2004-12-01

    The adulticidal activity of methanol extracts from three Malaysian plants namely Acorus calamus Linn., Litsea elliptica Blume and Piper aduncum Linn. against adult of Aedes aegypti (L.) were studied. Standard WHO bioassay tests were used to evaluate the effectiveness of these plant extracts. The hexane fraction from methanol extract of Acorus calamus rhizome was the most effective, exhibiting LC50 and LC90 values of 0.04 mgcm(-2) and 0.09 mgcm(-2) respectively. For L. elliptica, the methanol fraction also displayed good adulticidal property with the LC50 and LC90 values of 0.11 mgcm(-2) and 6.08 mgcm(-2) respectively. It is found that hexane fraction of the P. aduncum crude extract was the least effective among the three plants showing LC50 and LC90 values of 0.20 mgcm(-2) and 5.32 mgcm(-2), respectively. However, although A. calamus showed lowest LC values, the LT50 results indicated that the methanol fraction of L. elliptica was most potent extract among the extracts tested.