WorldWideScience

Sample records for open field habitats

  1. Modeling and measuring sound propagation of hooded crow calls in open field habitats

    DEFF Research Database (Denmark)

    Jensen, Kenneth Kragh; Larsen, Ole Næsbye; Attenborough, Keith

    representative of crow territorial communication and taking into account ground effect and air turbulence, we predict an optimal transmission frequency range between 0,5-1.6 kHz. In a natural open field crow habitat we measure, with sender and receiver heights of 2.8 m and transmission distances up to 320 m...... composite measures of sound degradation during transmission without taking the ground effect into account....

  2. Measurements and predictions of hooded crow (Corvus corone cornix) call propagation over open field habitats

    DEFF Research Database (Denmark)

    Jensen, Kenneth Kragh; Larsen, Ole Næsbye; Attenborough, Keith

    2008-01-01

    In a study of hooded crow communication over open fields an excellent correspondence is found between the attenuation spectra predicted by a "turbulence-modified ground effect plus atmospheric absorption" model, and crow call attenuation data. Sound propagation predictions and background noise...

  3. Physical condition, sex, and age-class of eastern red-backed salamanders (Plethodon cinereus) in forested and open habitats of West Virginia, USA

    Science.gov (United States)

    Breanna L. Riedel; Kevin R. Russell; W. Mark. Ford

    2012-01-01

    Nonforested habitats such as open fields and pastures have been considered unsuitable for desiccation-prone woodland salamanders such as the Eastern Red-backed Salamander (Plethodon cinereus). Recent research has suggested that Plethodon cinereus may not only disperse across but also reside within open habitats including fields,...

  4. Physical Condition, Sex, and Age-Class of Eastern Red-Backed Salamanders (Plethodon cinereus) in Forested and Open Habitats of West Virginia, USA

    OpenAIRE

    Riedel, Breanna L.; Russell, Kevin R.; W. Mark Ford

    2012-01-01

    Nonforested habitats such as open fields and pastures have been considered unsuitable for desiccation-prone woodland salamanders such as the Eastern Red-backed Salamander (Plethodon cinereus). Recent research has suggested that Plethodon cinereus may not only disperse across but also reside within open habitats including fields, meadows, and pastures. However, presence and high densities of P. cinereus within agriculturally disturbed habitats may be misleading if these populations exhibit aty...

  5. Deriving Animal Behaviour from High-Frequency GPS: Tracking Cows in Open and Forested Habitat.

    Science.gov (United States)

    de Weerd, Nelleke; van Langevelde, Frank; van Oeveren, Herman; Nolet, Bart A; Kölzsch, Andrea; Prins, Herbert H T; de Boer, W Fred

    2015-01-01

    The increasing spatiotemporal accuracy of Global Navigation Satellite Systems (GNSS) tracking systems opens the possibility to infer animal behaviour from tracking data. We studied the relationship between high-frequency GNSS data and behaviour, aimed at developing an easily interpretable classification method to infer behaviour from location data. Behavioural observations were carried out during tracking of cows (Bos Taurus) fitted with high-frequency GPS (Global Positioning System) receivers. Data were obtained in an open field and forested area, and movement metrics were calculated for 1 min, 12 s and 2 s intervals. We observed four behaviour types (Foraging, Lying, Standing and Walking). We subsequently used Classification and Regression Trees to classify the simultaneously obtained GPS data as these behaviour types, based on distances and turning angles between fixes. GPS data with a 1 min interval from the open field was classified correctly for more than 70% of the samples. Data from the 12 s and 2 s interval could not be classified successfully, emphasizing that the interval should be long enough for the behaviour to be defined by its characteristic movement metrics. Data obtained in the forested area were classified with a lower accuracy (57%) than the data from the open field, due to a larger positional error of GPS locations and differences in behavioural performance influenced by the habitat type. This demonstrates the importance of understanding the relationship between behaviour and movement metrics, derived from GNSS fixes at different frequencies and in different habitats, in order to successfully infer behaviour. When spatially accurate location data can be obtained, behaviour can be inferred from high-frequency GNSS fixes by calculating simple movement metrics and using easily interpretable decision trees. This allows for the combined study of animal behaviour and habitat use based on location data, and might make it possible to detect deviations

  6. Biodiversity of man-made open habitats in an underused country: a class of multispecies abundance models for count data

    Science.gov (United States)

    Yamaura, Yuichi; Royle, J. Andrew; Shimada, Naoaki; Asanuma, Seigo; Sato, Tamotsu; Taki, Hisatomo; Makino, Shun'ichi

    2012-01-01

    Since the 1960s, Japan has become highly dependent on foreign countries for natural resources, and the amount of managed lands (e.g. coppice, grassland, and agricultural field) has declined. Due to infrequent natural and human disturbance, early-successional species are now declining in Japan. Here we surveyed bees, birds, and plants in four human-disturbed open habitats (pasture, meadow, young planted forest, and abandoned clear-cut) and two forest habitats (mature planted forest and natural old-growth). We extended a recently developed multispecies abundance model to accommodate count data, and used the resulting models to estimate species-, functional group-, and community-level state variables (abundance and species richness) at each site, and compared them among the six habitats. Estimated individual-level detection probability was quite low for bee species (mean across species = 0.003; 0.16 for birds). Thirty-two (95% credible interval: 13-64) and one (0-4) bee and bird species, respectively, were suggested to be undetected by the field survey. Although habitats in which community-level abundance and species richness was highest differed among taxa, species richness and abundance of early-successional species were similar in the four disturbed open habitats across taxa except for plants in the pasture habitat which was a good habitat only for several exotic species. Our results suggest that human disturbance, especially the revival of plantation forestry, may contribute to the restoration of early-successional species in Japan

  7. Field Study Manual to Freshwater and Estuarine Habitats.

    Science.gov (United States)

    Georgia State Dept. of Education, Atlanta.

    This field studies manual, developed by biology students in the 1971 Georgia Governor's Honors Program, was designed for collection of data pertinent to freshwater and estuarine habitats. In addition to the various methods of sampling the ecosystem and for quantification of the data, instructions for dividing the field study into three logical…

  8. Forward Field Computation with OpenMEEG

    Directory of Open Access Journals (Sweden)

    Alexandre Gramfort

    2011-01-01

    must be computed. We present OpenMEEG, which solves the electromagnetic forward problem in the quasistatic regime, for head models with piecewise constant conductivity. The core of OpenMEEG consists of the symmetric Boundary Element Method, which is based on an extended Green Representation theorem. OpenMEEG is able to provide lead fields for four different electromagnetic forward problems: Electroencephalography (EEG, Magnetoencephalography (MEG, Electrical Impedance Tomography (EIT, and intracranial electric potentials (IPs. OpenMEEG is open source and multiplatform. It can be used from Python and Matlab in conjunction with toolboxes that solve the inverse problem; its integration within FieldTrip is operational since release 2.0.

  9. Open string fields as matrices

    Science.gov (United States)

    Kishimoto, Isao; Masuda, Toru; Takahashi, Tomohiko; Takemoto, Shoko

    2015-03-01

    We show that the action expanded around Erler-Maccaferri's N D-brane solution describes the N+1 D-brane system where one D-brane disappears due to tachyon condensation. String fields on multi-branes can be regarded as block matrices of a string field on a single D-brane in the same way as matrix theories.

  10. Open String Fields as Matrices

    CERN Document Server

    Kishimoto, Isao; Takahashi, Tomohiko; Takemoto, Shoko

    2014-01-01

    We show that the action expanded around Erler-Maccaferri's N D-branes solution describes the N+1 D-branes system where one D-brane disappears due to tachyon condensation. String fields on the multi-branes can be regarded as block matrices of a string field on a single D-brane in the same way as matrix theories.

  11. Habitat shifts in the evolutionary history of a Neotropical flycatcher lineage from forest and open landscapes.

    Science.gov (United States)

    Rheindt, Frank E; Christidis, Les; Norman, Janette A

    2008-07-07

    Little is known about the role ecological shifts play in the evolution of Neotropical radiations that have colonized a variety of environments. We here examine habitat shifts in the evolutionary history of Elaenia flycatchers, a Neotropical bird lineage that lives in a range of forest and open habitats. We evaluate phylogenetic relationships within the genus based on mitochondrial and nuclear DNA sequence data, and then employ parsimony-based and Bayesian methods to reconstruct preferences for a number of habitat types and migratory behaviour throughout the evolutionary history of the genus. Using a molecular clock approach, we date the most important habitat shifts. Our analyses resolve phylogenetic relationships among Elaenia species and confirm several species associations predicted by morphology while furnishing support for other taxon placements that are in conflict with traditional classification, such as the elevation of various Elaenia taxa to species level. While savannah specialism is restricted to one basal clade within the genus, montane forest was invaded from open habitat only on a limited number of occasions. Riparian growth may have been favoured early on in the evolution of the main Elaenia clade and subsequently been deserted on several occasions. Austral long-distance migratory behaviour evolved on several occasions. Ancestral reconstructions of habitat preferences reveal pronounced differences not only in the timing of the emergence of certain habitat preferences, but also in the frequency of habitat shifts. The early origin of savannah specialism in Elaenia highlights the importance of this habitat in Neotropical Pliocene and late Miocene biogeography. While forest in old mountain ranges such as the Tepuis and the Brazilian Shield was colonized early on, the most important colonization event of montane forest was in conjunction with Pliocene Andean uplift. Riparian habitats may have played an important role in facilitating habitat shifts by

  12. Habitat shifts in the evolutionary history of a Neotropical flycatcher lineage from forest and open landscapes

    Directory of Open Access Journals (Sweden)

    Christidis Les

    2008-07-01

    Full Text Available Abstract Background Little is known about the role ecological shifts play in the evolution of Neotropical radiations that have colonized a variety of environments. We here examine habitat shifts in the evolutionary history of Elaenia flycatchers, a Neotropical bird lineage that lives in a range of forest and open habitats. We evaluate phylogenetic relationships within the genus based on mitochondrial and nuclear DNA sequence data, and then employ parsimony-based and Bayesian methods to reconstruct preferences for a number of habitat types and migratory behaviour throughout the evolutionary history of the genus. Using a molecular clock approach, we date the most important habitat shifts. Results Our analyses resolve phylogenetic relationships among Elaenia species and confirm several species associations predicted by morphology while furnishing support for other taxon placements that are in conflict with traditional classification, such as the elevation of various Elaenia taxa to species level. While savannah specialism is restricted to one basal clade within the genus, montane forest was invaded from open habitat only on a limited number of occasions. Riparian growth may have been favoured early on in the evolution of the main Elaenia clade and subsequently been deserted on several occasions. Austral long-distance migratory behaviour evolved on several occasions. Conclusion Ancestral reconstructions of habitat preferences reveal pronounced differences not only in the timing of the emergence of certain habitat preferences, but also in the frequency of habitat shifts. The early origin of savannah specialism in Elaenia highlights the importance of this habitat in Neotropical Pliocene and late Miocene biogeography. While forest in old mountain ranges such as the Tepuis and the Brazilian Shield was colonized early on, the most important colonization event of montane forest was in conjunction with Pliocene Andean uplift. Riparian habitats may have

  13. Forward field computation with OpenMEEG.

    Science.gov (United States)

    Gramfort, Alexandre; Papadopoulo, Théodore; Olivi, Emmanuel; Clerc, Maureen

    2011-01-01

    To recover the sources giving rise to electro- and magnetoencephalography in individual measurements, realistic physiological modeling is required, and accurate numerical solutions must be computed. We present OpenMEEG, which solves the electromagnetic forward problem in the quasistatic regime, for head models with piecewise constant conductivity. The core of OpenMEEG consists of the symmetric Boundary Element Method, which is based on an extended Green Representation theorem. OpenMEEG is able to provide lead fields for four different electromagnetic forward problems: Electroencephalography (EEG), Magnetoencephalography (MEG), Electrical Impedance Tomography (EIT), and intracranial electric potentials (IPs). OpenMEEG is open source and multiplatform. It can be used from Python and Matlab in conjunction with toolboxes that solve the inverse problem; its integration within FieldTrip is operational since release 2.0.

  14. Planning open spaces for Biodiversity: Evaluating Urban Parks for Wildlife Habitat

    Directory of Open Access Journals (Sweden)

    Margaret Livingston

    2004-06-01

    Full Text Available Natural open spaces adjacent to developing cities are frequently affected by advancing urban sprawl. It requires a delicate balancing act to conserve habitats while developing new environments for city inhabitants. As landscape architects, planners, and managers of these areas, we continue to explore mitigation strategies for habitats affected by development. One strategy focuses on creating new spaces within development that can fulfil some of the functions previously provided by natural areas and serve as resource links among remaining peripheral natural areas (Forman and Godron, 1986. Previous research has shown that created open spaces, such as parks and golf courses may provide critical habitat functions associated with natural areas if planned appropriately (Mannan and Boal, 2000; Shaw et al, 1998. However, few studies have evaluated the specific characteristics associated with created open spaces for their wildlife habitat value. This research addresses the following question: What is the potential habitat value of current vegetation in urban parks in Tucson, Arizona? The goals of this study were to: 1 evaluate potential habitat value of urban parks using a wildlife habitat value index (Shaw et al, 1998, and 2 provide recommendations emphasising increased biodiversity through habitat development in these open spaces. Most vegetation in the surveyed parks was non-native and provided little escape cover for wildlife. Plant species richness and abundance were relatively low in most parks, but higher for sites where existing native vegetation was incorporated into the park. Recommendations emphasise: 1 appropriate arrangement and placement of species based on functions required by human and wildlife users; 2 increased horizontal and vertical vegetation layers; 3 design focus on regional plant communities; and 4 development of written specifications for parks that address design uses of native species and their maintenance.

  15. Thigmotactic responses in an open-field

    Directory of Open Access Journals (Sweden)

    M.R. Lamprea

    2008-02-01

    Full Text Available The goal of the present study was to investigate the role of thigmotaxis (the tendency to remain close to vertical surfaces in rat exploratory behavior in an open-field. Thigmotaxis was investigated in a parametric way, using 24 experimentally adult naive male Wistar rats (210-230 g. Exploratory behavior was studied in an open-field (N = 12 in 5-min sessions and behavior was analyzed in terms of where it occurred: in areas surrounded by two, one, or no walls. Another group of rats (N = 12 was studied in an open-field with blocks placed near two of the corners so as to make these corner areas surrounded by three walls. The floor of the open-fields was divided into 20-cm squares in order to locate the exact place of occurrence of each behavior. The following behaviors were recorded: entries into the squares, rearings, and groomings. In both types of open-field the rats chose to remain longer in the squares surrounded by the largest possible number of walls. In one of the open-fields, the mean time (seconds spent in squares surrounded by two walls was longer than the time spent in squares surrounded by one or no walls (37.2, 7.7, and 1.8 s, respectively. In the other open-field, the mean time spent in squares surrounded by three walls was longer than the time spent in squares surrounded by two, one or no walls (41.7, 20.4, 7.0, and 2.6 s, respectively. Other measures presented a similar profile. These results indicate that rats are sensitive to the number of walls in an environment and prefer to remain close to them.

  16. Canopy cover negatively affects arboreal ant species richness in a tropical open habitat

    Directory of Open Access Journals (Sweden)

    A. C. M. Queiroz

    Full Text Available Abstract We tested the hypothesis of a negative relationship between vegetation characteristics and ant species richness in a Brazilian open vegetation habitat, called candeial. We set up arboreal pitfalls to sample arboreal ants and measured the following environmental variables, which were used as surrogate of environmental heterogeneity: tree richness, tree density, tree height, circumference at the base of the plants, and canopy cover. Only canopy cover had a negative effect on the arboreal ant species richness. Vegetation characteristics and plant species composition are probably homogeneous in candeial, which explains the lack of relationship between other environmental variables and ant richness. Open vegetation habitats harbor a large number of opportunistic and generalist species, besides specialist ants from habitats with high temperatures. An increase in canopy cover decreases sunlight incidence and may cause local microclimatic differences, which negatively affect the species richness of specialist ants from open areas. Canopy cover regulates the richness of arboreal ants in open areas, since only few ant species are able to colonize sites with dense vegetation; most species are present in sites with high temperature and luminosity. Within open vegetation habitats the relationship between vegetation characteristics and species richness seems to be the opposite from closed vegetation areas, like forests.

  17. Human habitation field study of the Habitat Demonstration Unit (HDU)

    Science.gov (United States)

    Litaker, Harry L.; Archer, Ronald D.; Szabo, Richard; Twyford, Evan S.; Conlee, Carl S.; Howard, Robert L.

    2013-10-01

    Landing and supporting a permanent outpost on a planetary surface represents humankind's capability to expand its own horizons and challenge current technology. With this in mind, habitability of these structures becomes more essential given the longer durations of the missions. The purpose of this evaluation was to obtain preliminary human-in-the-loop performance data on the Habitat Demonstration Unit (HDU) in a Pressurized Excursion Module (PEM) configuration during a 14-day simulated lunar exploration field trial and to apply this knowledge to further enhance the habitat's capabilities for forward designs. Human factors engineers at the NASA/Johnson Space Center's Habitability and Human Factors Branch recorded approximately 96 h of crew task performance with four work stations. Human factors measures used during this study included the NASA Task Load Index (TLX) and customized post questionnaires. Overall the volume for the PEM was considered acceptable by the crew; however; the habitat's individual work station volume was constrained when setting up the vehicle for operation, medical operations, and suit maintenance while general maintenance, logistical resupply, and geo science was considered acceptable. Crew workload for each station indicated resupply as being the lowest rated, with medical operations, general maintenance, and geo science tasks as being light, while suit maintenance was considered moderate and general vehicle setup being rated the highest. Stowage was an issue around the habitat with the Space Exploration Vehicle (SEV) resupply stowage located in the center of the habitat as interfering with some work station volumes and activities. Ergonomics of the geo science station was considered a major issue, especially with the overhead touch screens.

  18. Supersymmetry in Open Superstring Field Theory

    CERN Document Server

    Erler, Theodore

    2016-01-01

    We realize the 16 unbroken supersymmetries on a BPS D-brane as invariances of the action of the corresponding open superstring field theory. We work in the small Hilbert space approach, where a symmetry of the action translates into a symmetry of the associated cyclic $A_\\infty$ structure. We compute the supersymmetry algebra, being careful to disentangle the components which produce a translation, a gauge transformation, and a symmetry transformation which vanishes on-shell. Via the minimal model theorem, we illustrate how supersymmetry of the action implies supersymmetry of the tree level open string scattering amplitudes.

  19. Connectivity of the habitat-forming kelp, Ecklonia radiata within and among estuaries and open coast.

    Science.gov (United States)

    Coleman, Melinda A

    2013-01-01

    With marine protected areas being established worldwide there is a pressing need to understand how the physical setting in which these areas are placed influences patterns of dispersal and connectivity of important marine organisms. This is particularly critical for dynamic and complex nearshore marine environments where patterns of genetic structure of organisms are often chaotic and uncoupled from broad scale physical processes. This study determines the influence of habitat heterogeneity (presence of estuaries) on patterns of genetic structure and connectivity of the common kelp, Ecklonia radiata. There was no genetic differentiation of kelp between estuaries and the open coast and the presence of estuaries did not increase genetic differentiation among open coast populations. Similarly, there were no differences in level of inbreeding or genetic diversity between estuarine and open coast populations. The presence of large estuaries along rocky coastlines does not appear to influence genetic structure of this kelp and factors other than physical heterogeneity of habitat are likely more important determinants of regional connectivity. Marine reserves are currently lacking in this bioregion and may be designated in the future. Knowledge of the factors that influence important habitat forming organisms such as kelp contribute to informed and effective marine protected area design and conservation initiatives to maintain resilience of important marine habitats.

  20. Connectivity of the habitat-forming kelp, Ecklonia radiata within and among estuaries and open coast.

    Directory of Open Access Journals (Sweden)

    Melinda A Coleman

    Full Text Available With marine protected areas being established worldwide there is a pressing need to understand how the physical setting in which these areas are placed influences patterns of dispersal and connectivity of important marine organisms. This is particularly critical for dynamic and complex nearshore marine environments where patterns of genetic structure of organisms are often chaotic and uncoupled from broad scale physical processes. This study determines the influence of habitat heterogeneity (presence of estuaries on patterns of genetic structure and connectivity of the common kelp, Ecklonia radiata. There was no genetic differentiation of kelp between estuaries and the open coast and the presence of estuaries did not increase genetic differentiation among open coast populations. Similarly, there were no differences in level of inbreeding or genetic diversity between estuarine and open coast populations. The presence of large estuaries along rocky coastlines does not appear to influence genetic structure of this kelp and factors other than physical heterogeneity of habitat are likely more important determinants of regional connectivity. Marine reserves are currently lacking in this bioregion and may be designated in the future. Knowledge of the factors that influence important habitat forming organisms such as kelp contribute to informed and effective marine protected area design and conservation initiatives to maintain resilience of important marine habitats.

  1. Indices of environmental temperatures for primates in open habitats.

    Science.gov (United States)

    Hill, Russell A; Weingrill, Tony; Barrett, Louise; Henzi, S Peter; Hill, Russel A; Barrett, Luise

    2004-01-01

    Studies of thermoregulation in primates are under-represented in the literature, although there is sufficient evidence to suggest that temperature represents an important ecological constraint. One of the problems in examining thermoregulation in primates, however, is the difficulty in quantifying the thermal environment, since shade temperatures, solar radiation, humidity and wind speed all serve to alter an animal's 'perceived' temperature. Since animals respond to their perceived temperature, we need methods to account for each of these factors, both individually and collectively, if we are to understand the integrated impact of the thermal environment on primates. Here, we present a review of some thermal indices currently available. Black bulb temperatures can account for the effect of solar radiation, with wind chill equivalent temperatures and the heat index providing quantifiable estimates of the relative impact of wind speed and humidity, respectively. We present three potential indices of the 'perceived environmental temperature' (PET) that account for the combined impact of solar radiation, humidity and wind speed on temperature, and perform a preliminary test of all of the climatic indices against behavioural data from a field study of chacma baboons ( Papio cynocephalus ursinus) at De Hoop Nature Reserve, South Africa. One measure of the perceived environmental temperature, PET2, is an effective thermal index, since it enters the models for feeding and resting behaviour, and also accounts for levels of allogrooming. Solar radiation intensity is an important factor underlying these relationships, although the wind chill equivalent temperature and humidity enter the models for other behaviours. Future studies should thus be mindful of the impact of each of these elements of the thermal environment. A detailed understanding of primate thermoregulation will only come with the development of biophysical models of the thermal characteristics of the species

  2. Differential fitness in field and forest explains density-independent habitat selection by gartersnakes.

    Science.gov (United States)

    Halliday, William D; Blouin-Demers, Gabriel

    2016-07-01

    The ideal free distribution concept predicts that organisms will distribute themselves between habitats in a density-dependent manner so that individuals, on average, achieve the same fitness in each habitat. In ectotherms, environmental temperature has a strong impact on fitness, but temperature is not depletable and thus not density dependent. Can density-dependent habitat selection occur in ectotherms when habitats differ in thermal quality? We used an observational study of habitat selection by small snakes in field and forest, followed by manipulative habitat selection and fitness experiments with common gartersnakes in enclosures in field and forest to test this hypothesis. Snakes were much more abundant in the field, the habitat with superior thermal quality, than in the forest. Gartersnakes in our controlled experiment only used the forest habitat when snake density was highest and when food was more abundant in the forest; habitat selection was largely density independent, although there was weak evidence of density dependence. No female gartersnake gave birth in the forest enclosures, whereas half of the females gave birth in the field enclosures. Growth rates of females were higher in field than in forest enclosures. Overall, our data indicate that temperature appears to be the most important factor driving the habitat selection of gartersnakes, likely because temperature was more limiting than food in our study system. Snakes, or at least temperate snakes, may naturally exist at population densities low enough that they do not exhibit density-dependent habitat selection.

  3. Thermo-Field Extension of Open String Field Theory

    CERN Document Server

    Cantcheff, M Botta

    2015-01-01

    We study the implementation of Thermo Field Dynamics (TFD) to the covariant formulation of Open String Field Theory (OSFT). In this paper, we extend the state space and fields according to the duplication rules of TFD and construct the corresponding classical action. The result is a theory whose fields would encode the statistical information of open strings and, noticeably, present degrees of freedom that could be identified as those of closed strings. The physical spectrum of the free theory is studied through the cohomology of the extended BRST charge, and, as a result, we get new fields in the spectrum. We also show, however, that their appearing in the action is directly related to the choice of the inner product in the extended algebra, so that many fields could be eliminated from the theory by choosing that product conveniently. Finally, we study the extension of the three-vertex interaction and provide a simple prescription for it whose results at tree-level amplitudes agree with those of the conventi...

  4. Physical Condition, Sex, and Age-Class of Eastern Red-Backed Salamanders (Plethodon cinereus in Forested and Open Habitats of West Virginia, USA

    Directory of Open Access Journals (Sweden)

    Breanna L. Riedel

    2012-01-01

    Full Text Available Nonforested habitats such as open fields and pastures have been considered unsuitable for desiccation-prone woodland salamanders such as the Eastern Red-backed Salamander (Plethodon cinereus. Recent research has suggested that Plethodon cinereus may not only disperse across but also reside within open habitats including fields, meadows, and pastures. However, presence and high densities of P. cinereus within agriculturally disturbed habitats may be misleading if these populations exhibit atypical demographic characteristics or decreased physical condition relative to forest populations. We surveyed artificial cover boards from 2004-2005 to compare physical condition, sex ratios, and age-class structure of P. cinereus among woodland, woodland-meadow edge, silvopasture, and meadow sites in the central Appalachian Mountains of southern West Virginia. Physical condition of salamanders was not significantly different among the four habitats. Furthermore, adult sex ratios of P. cinereus typically were not significantly different from 1 : 1 and were similar between forested and non-forested sites, although populations within silvopastures were biased towards females. However, adult salamanders were significantly more abundant than juveniles in all habitat types, with differences most pronounced within meadow habitats. Our study indicates that relatively small, non-forested habitats such as silvopastures and meadows may not adversely affect the overall physical condition or sex ratios of Plethodon cinereus. However, the paucity of juveniles within disturbed meadows indicates that these agriculturally modified habitats may negatively impact reproduction or that immature salamanders are at a physiological or competitive disadvantage in comparison to adults, particularly when surface cover is limited.

  5. Plasma opening switch with extrinsic magnetic field

    CERN Document Server

    Dolgachev, G; Maslennikov, D

    2001-01-01

    Summary form only given, as follows. We have demonstrated in series of experiments that plasma opening switch (POS) switching voltage (UPOS) is defined by energy density (w) deposited in the POS plasma. If we then consider a plasma erosion mainly responsible for the effect of POS switching (the erosion effect could be described by Hall or Child-Langmuir models) the energy density (w) could be measured as a function of a system "macro-parameter" such as the initial charging voltage of the capacity storage system (the Marx pulsed voltage generator) UMarx. The POS voltage in this case could be given by UPOS"aw=aUMarx4/7, where a is a constant. This report demonstrates that for the high-impedance POS which has limited charge density transferred through the POS plasma a"2.5 (MV3/7) with no external magnetic field applied. The use of the extrinsic magnetic field allows to increase a up to 3.6 (MV3/7) and to achieve higher voltages at the opening phase - UPOS=3.6UMarx4/7. To verify this approach set of experimental ...

  6. Feral Cats Are Better Killers in Open Habitats, Revealed by Animal-Borne Video.

    Science.gov (United States)

    McGregor, Hugh; Legge, Sarah; Jones, Menna E; Johnson, Christopher N

    2015-01-01

    One of the key gaps in understanding the impacts of predation by small mammalian predators on prey is how habitat structure affects the hunting success of small predators, such as feral cats. These effects are poorly understood due to the difficulty of observing actual hunting behaviours. We attached collar-mounted video cameras to feral cats living in a tropical savanna environment in northern Australia, and measured variation in hunting success among different microhabitats (open areas, dense grass and complex rocks). From 89 hours of footage, we recorded 101 hunting events, of which 32 were successful. Of these kills, 28% were not eaten. Hunting success was highly dependent on microhabitat structure surrounding prey, increasing from 17% in habitats with dense grass or complex rocks to 70% in open areas. This research shows that habitat structure has a profound influence on the impacts of small predators on their prey. This has broad implications for management of vegetation and disturbance processes (like fire and grazing) in areas where feral cats threaten native fauna. Maintaining complex vegetation cover can reduce predation rates of small prey species from feral cat predation.

  7. Feral Cats Are Better Killers in Open Habitats, Revealed by Animal-Borne Video.

    Directory of Open Access Journals (Sweden)

    Hugh McGregor

    Full Text Available One of the key gaps in understanding the impacts of predation by small mammalian predators on prey is how habitat structure affects the hunting success of small predators, such as feral cats. These effects are poorly understood due to the difficulty of observing actual hunting behaviours. We attached collar-mounted video cameras to feral cats living in a tropical savanna environment in northern Australia, and measured variation in hunting success among different microhabitats (open areas, dense grass and complex rocks. From 89 hours of footage, we recorded 101 hunting events, of which 32 were successful. Of these kills, 28% were not eaten. Hunting success was highly dependent on microhabitat structure surrounding prey, increasing from 17% in habitats with dense grass or complex rocks to 70% in open areas. This research shows that habitat structure has a profound influence on the impacts of small predators on their prey. This has broad implications for management of vegetation and disturbance processes (like fire and grazing in areas where feral cats threaten native fauna. Maintaining complex vegetation cover can reduce predation rates of small prey species from feral cat predation.

  8. Allelochemicals of Pinus halepensis as drivers of biodiversity in Mediterranean open mosaic habitats during the colonization stage of secondary succession.

    Science.gov (United States)

    Fernandez, Catherine; Santonja, Mathieu; Gros, Raphael; Monnier, Yogan; Chomel, Mathilde; Baldy, Virginie; Bousquet-Mélou, Anne

    2013-02-01

    The Mediterranean region is recognized as a global biodiversity hotspot. However, over the last 50 years or so, the cessation of traditional farming has given way to strong afforestation at the expense of open habitats. Pinus halepensis Miller, known to synthesize a wide range of secondary metabolites, is a pioneer expansionist species colonizing abandoned agricultural land that present high species richness. Here, laboratory bioassays were used to study the potential impact of P. halepensis on plant diversity through allelopathy, and the role of microorganisms in these interactions. Germination and growth of 12 target species naturally present in fallow farmlands were tested according to concentration of aqueous extracts obtained from shoots of young pines (aged about 5 years), with or without the presence of soil microorganisms (autoclaved or natural soil). Under the highest concentrations and autoclaved soil, more than 80 % of target species were germination and/or growth-inhibited, and only two species were non-sensitive. Under more natural conditions (lower extracts concentrations and natural soil with microorganisms), only 50 % of species were still inhibited, one was non-sensitive, and five were stimulated. Thus, microorganisms alter the expression of allelochemicals released into the ecosystem, which highlights their key role in chemical plant-plant interactions. The results of allelopathic experiments conducted in the lab are consistent with the community patterns observed in the field. These findings suggest that allelopathy is likely to shape vegetation composition and participate to the control of biodiversity in Mediterranean open mosaic habitats.

  9. Adjacent habitat influence on stink bug (Hemiptera: Pentatomidae densities and the associated damage at field corn and soybean edges.

    Directory of Open Access Journals (Sweden)

    P Dilip Venugopal

    Full Text Available The local dispersal of polyphagous, mobile insects within agricultural systems impacts pest management. In the mid-Atlantic region of the United States, stink bugs, especially the invasive Halyomorpha halys (Stål 1855, contribute to economic losses across a range of cropping systems. Here, we characterized the density of stink bugs along the field edges of field corn and soybean at different study sites. Specifically, we examined the influence of adjacent managed and natural habitats on the density of stink bugs in corn and soybean fields at different distances along transects from the field edge. We also quantified damage to corn grain, and to soybean pods and seeds, and measured yield in relation to the observed stink bug densities at different distances from field edge. Highest density of stink bugs was limited to the edge of both corn and soybean fields. Fields adjacent to wooded, crop and building habitats harbored higher densities of stink bugs than those adjacent to open habitats. Damage to corn kernels and to soybean pods and seeds increased with stink bug density in plots and was highest at the field edges. Stink bug density was also negatively associated with yield per plant in soybean. The spatial pattern of stink bugs in both corn and soybeans, with significant edge effects, suggests the use of pest management strategies for crop placement in the landscape, as well as spatially targeted pest suppression within fields.

  10. Flowers visited by hummingbirds in the open habitats of the southeastern brazilian mountaintops: species composition and seasonality

    Directory of Open Access Journals (Sweden)

    LC Rodrigues

    Full Text Available The hummingbird-visited plant community located on the open-habitat mountaintop of the Espinhaço Range was studied for two years (from August 2007 to July 2009 in Serra do Cipó National Park, Southeastern Brazil (19° 15′ S and 43° 31′ W. The floral characteristics and flowering period of the hummingbird-visited plants was monthly recorded along trails located in three vegetation types: (1 typical campos rupestres (TCR, (2 open fields (OPF, and (3 capões de mata(CAM. Hummingbird visitation was observed in 51 plant species, 22 ornithophilous and 29 non-ornithophilous species. The TCR showed the greatest number of species visited (N = 38, followed by the OPF (N = 18 and CAM (N = 17. Six species of hummingbirds were recorded visiting flowers: Augastes scutatus, Campylopterus largipennis, Colibri serrirostris, Chlorostilbon lucidus, Eupetomena macroura and Phaethornis pretrei. This study demonstrates that the species richness and the number of ornithophilous species visited by the hummingbirds at the study site are more similar to hummingbird-plant communities of the Atlantic Forest than to those of the Cerrado communities and other Brazilian highland open-habitat communities. The plant families most visited by hummingbirds were Bromeliaceae and Asteraceae. Although the Asteraceae family is rarely used as a food resource for hummingbirds in other high and lowland communities, in the study site this family is used mainly by the endemic hummingbird Augastes scutatus. We found a large overlap of flowering throughout the year among the species visited by the hummingbirds. Thus, the nectar availability supports these resident hummingbirds. The present study also showed that the studied hummingbird-plant community is composed of many species endemic to the campos rupestres of the Espinhaço Range, some of which are considered to be in danger of extinction, thus constituting a unique and threatened community. Thus, understanding hummingbird

  11. Flowers visited by hummingbirds in the open habitats of the southeastern Brazilian mountaintops: species composition and seasonality.

    Science.gov (United States)

    Rodrigues, L C; Rodrigues, M

    2014-08-01

    The hummingbird-visited plant community located on the open-habitat mountaintop of the Espinhaço Range was studied for two years (from August 2007 to July 2009) in Serra do Cipó National Park, Southeastern Brazil (19° 15' S and 43° 31' W). The floral characteristics and flowering period of the hummingbird-visited plants was monthly recorded along trails located in three vegetation types: (1) typical campos rupestres (TCR), (2) open fields (OPF), and (3) capões de mata (CAM). Hummingbird visitation was observed in 51 plant species, 22 ornithophilous and 29 non-ornithophilous species. The TCR showed the greatest number of species visited (N = 38), followed by the OPF (N = 18) and CAM (N = 17). Six species of hummingbirds were recorded visiting flowers: Augastes scutatus, Campylopterus largipennis, Colibri serrirostris, Chlorostilbon lucidus, Eupetomena macroura and Phaethornis pretrei. This study demonstrates that the species richness and the number of ornithophilous species visited by the hummingbirds at the study site are more similar to hummingbird-plant communities of the Atlantic Forest than to those of the Cerrado communities and other Brazilian highland open-habitat communities. The plant families most visited by hummingbirds were Bromeliaceae and Asteraceae. Although the Asteraceae family is rarely used as a food resource for hummingbirds in other high and lowland communities, in the study site this family is used mainly by the endemic hummingbird Augastes scutatus. We found a large overlap of flowering throughout the year among the species visited by the hummingbirds. Thus, the nectar availability supports these resident hummingbirds. The present study also showed that the studied hummingbird-plant community is composed of many species endemic to the campos rupestres of the Espinhaço Range, some of which are considered to be in danger of extinction, thus constituting a unique and threatened community. Thus, understanding hummingbird-plant pollination

  12. Forward Field Computation with OpenMEEG

    OpenAIRE

    2011-01-01

    To recover the sources giving rise to electro- and magnetoencephalography in individual measurements, realistic physiological modeling is required, and accurate numerical solutions must be computed. We present OpenMEEG, which solves the electromagnetic forward problem in the quasistatic regime, for head models with piecewise constant conductivity. The core of OpenMEEG consists of the symmetric Boundary Element Method, which is based on an extended Green Representation theorem. OpenMEEG is abl...

  13. Analytic solutions for marginal deformations in open superstring field theory

    Energy Technology Data Exchange (ETDEWEB)

    Okawa, Y.

    2007-04-15

    We extend the calculable analytic approach to marginal deformations recently developed in open bosonic string field theory to open superstring field theory formulated by Berkovits. We construct analytic solutions to all orders in the deformation parameter when operator products made of the marginal operator and the associated superconformal primary field are regular. (orig.)

  14. Decoupled taxonomic radiation and ecological expansion of open-habitat grasses in the Cenozoic of North America.

    Science.gov (United States)

    Strömberg, Caroline A E

    2005-08-23

    Because of a dearth of Cenozoic grass fossils, the timing of the taxonomic diversification of modern subclades within the grass family (Poaceae) and the rise to ecological dominance of open-habitat grasses remain obscure. Here, I present data from 99 Eocene to Miocene phytolith assemblages from the North American continental interior (Colorado, Nebraska, Wyoming, and Montana/Idaho), constituting the only high-resolution mid-Cenozoic record of grasses. Analyses of these assemblages show that open-habitat grasses had undergone considerable taxonomic diversification by the earliest Oligocene (34 million years ago) but that they did not become ecologically dominant in North America until 7-11 million years later (Late Oligocene or Early Miocene). This pattern of decoupling suggests that environmental changes (e.g., climate changes), rather than taxonomic radiations within Poaceae, provided the key opportunity for open-habitat grasses to expand in North America.

  15. Comparative efficacy of three suction traps for collecting phlebotomine sand flies (Diptera: Psychodidae) in open habitats.

    Science.gov (United States)

    Faiman, Roy; Cuño, Ruben; Warburg, Alon

    2009-06-01

    The efficacy of three suction traps for trapping phlebotomine sand flies (Diptera: Psychodidae) was compared. Traps were baited with Co(2) and used without any light source. CO(2)-baited CDC traps were evaluated either in their standard downdraft orientation or inverted (iCDC traps). Mosquito Magnet-X (MMX) counterflow geometry traps were tested in the updraft orientation only. Both updraft traps (iCDC and MMX) were deployed with their opening ∼10 cm from the ground while the opening of the downdraft (CDC) trap was ∼40 cm above ground. Comparisons were conducted in two arid locations where different sand fly species prevail. In the Jordan Valley, 3,367 sand flies were caught, 2,370 of which were females. The predominant species was Phlebotomus (Phlebotomus) papatasi, Scopoli 1786 (>99%). The updraft-type traps iCDC and MMX caught an average of 118 and 67.1 sand flies per trap night, respectively. The CDC trap caught 32.9 sand flies on average per night, significantly less than the iCDC traps. In the Judean desert, traps were arranged in a 3 × 3 Latin square design. A total of 565 sand flies were caught, 345 of which were females. The predominant species was P. (Paraphlebotomus) sergenti Parrot 1917 (87%). The updraft traps iCDC and MMX caught an average of 25.6 and 17.9 sand flies per trap per night, respectively. The CDC trap caught 7.8 sand flies on average per night, significantly less than the iCDC traps. The female to male ratio was 1.7 on average for all trap types. In conclusion, updraft traps deployed with their opening close to the ground are clearly more effective for trapping sand flies than downdraft CDC traps in open habitats.

  16. Cotton fields drive elephant habitat fragmentation in the Mid Zambezi Valley, Zimbabwe

    Science.gov (United States)

    Sibanda, Mbulisi; Murwira, Amon

    2012-10-01

    In this study we tested whether cotton fields contribute more than cereal fields to African elephant (Loxodonta africana) habitat loss through its effects on woodland fragmentation in the Mid-Zambezi Valley, Zimbabwe. In order to test this hypothesis, we first mapped cotton and cereal fields using MODIS remotely sensed data. Secondly, we analysed the effect of the area of cotton and cereal fields on woodland fragmentation using regression analysis. We then related the fragmentation indices, particularly edge density with elephant distribution data to test whether elephant distribution was significantly related with woodland fragmentation resulting from cotton fields. Our results showed that cotton fields contributed more to woodland fragmentation than cereal fields. In addition, results showed that the frequency of the African elephant increased where cotton fields were many and small relative to cereal fields. We concluded that cotton fields are the main driver of woodland fragmentation and therefore elephant habitat in the Mid-Zambezi Valley compared with cereal fields.

  17. Slow mode shocks propagating in open and closed magnetic fields

    Institute of Scientific and Technical Information of China (English)

    吕建永; 魏奉思

    1999-01-01

    A 2-D MHD model is used to investigate the propagation of slow mode shocks in the open and closed magnetic fields of the meridional plane near the sun. The solutions demonstrate that a forward slow shock could retain its slow shock characteristics into interplanetary space in the magnetically open region; however, it can evolve into an intermediate shock through the helmet-type current sheet to the open magnetic field.

  18. Illinois Natural Heritage Conservation/Education Kit III. Special Theme: Prairie and Open Habitats Ecology and Management.

    Science.gov (United States)

    Stone, Sally F.

    This instructional guide contains 15 activities and exercises designed to help teachers familiarize their students with prairie and open habitat resources of Illinois. Each activity or exercise is ready to be copied and given to students. Activities include: (1) making a marsh hawk model; (2) building a prairie ecosystem; (3) investigating food…

  19. Opening the cusp. [using magnetic field topology

    Science.gov (United States)

    Crooker, N. U.; Toffoletto, F. R.; Gussenhoven, M. S.

    1991-01-01

    This paper discusses the magnetic field topology (determined by the superposition of dipole, image, and uniform fields) for mapping the cusp to the ionosphere. The model results are compared to both new and published observations and are then used to map the footprint of a flux transfer event caused by a time variation in the merging rate. It is shown that the cusp geometry distorts the field lines mapped from the magnetopause to yield footprints with dawn and dusk protrusions into the region of closed magnetic flux.

  20. Large optical field enhancement for nanotips with large opening angles

    CERN Document Server

    Thomas, Sebastian; Lemell, Christoph; Burgdörfer, Joachim; Hommelhoff, Peter

    2014-01-01

    We theoretically investigate optical near-fields at nanometric tips. We systematically study the dependence of field enhancement on the shape, size, and material of the tip. We confirm a strong dependence of the field enhancement factor on the radius of curvature. In addition, we find a remarkably strong increase of field enhancement with increasing opening angle of the nanotips. For gold and tungsten nanotips in the experimentally relevant parameter range (radius of curvature $\\geq 5\\,$nm at 800 nm laser wavelength), we obtain field enhancement factors of up to ${\\sim}35$ (Au) and ${\\sim}12$ (W) for wide opening angles. We confirm this strong dependence on the opening angle for many other materials studying the dependence of the field enhancement at nanotips on the dielectric response function. For dielectrics, the increase in field enhancement is traced back to the electrostatic force of the induced surface charge at the tip shank. For metals, the plasmonic response strongly increases the field enhancement ...

  1. The electromagnetic field for an open magnetosphere

    Science.gov (United States)

    Heikkila, W. J.

    1984-01-01

    The boundary-layer-dominated models of the earth EM field developed by Heikkila (1975, 1978, 1982, and 1983) and Heikkila et al. (1979) to account for deficiencies in the electric-field descriptions of quasi-steady-state magnetic-field-reconnection models (such as that of Cowley, 1980) are characterized, reviewing the arguments and indicating the most important implications. The mechanisms of boundary-layer formation and field direction reversal are explained and illustrated with diagrams, and it is inferred that boundary-layer phenomena rather than magnetic reconnection may be the cause of large-scale magnetospheric circulation, convection, plasma-sheet formation and sunward convection, and auroras, the boundary layer acting basically as a viscous process mediating solar-wind/magnetosphere interactions.

  2. Floral and nesting resources, habitat structure, and fire influence bee distribution across an open-forest gradient.

    Science.gov (United States)

    Grundel, Ralph; Jean, Robert P; Frohnapple, Krystalynn J; Glowacki, Gary A; Scott, Peter E; Pavlovic, Noel B

    2010-09-01

    Given bees' central effect on vegetation communities, it is important to understand how and why bee distributions vary across ecological gradients. We examined how plant community composition, plant diversity, nesting suitability, canopy cover, land use, and fire history affected bee distribution across an open-forest gradient in northwest Indiana, USA, a gradient similar to the historic Midwest United States landscape mosaic. When considered with the other predictors, plant community composition was not a significant predictor of bee community composition. Bee abundance was negatively related to canopy cover and positively to recent fire frequency, bee richness was positively related to plant richness and abundance of potential nesting resources, and bee community composition was significantly related to plant richness, soil characteristics potentially related to nesting suitability, and canopy cover. Thus, bee abundance was predicted by a different set of environmental characteristics than was bee species richness, and bee community composition was predicted, in large part, by a combination of the significant predictors of bee abundance and richness. Differences in bee community composition along the woody vegetation gradient were correlated with relative abundance of oligolectic, or diet specialist, bees. Because oligoleges were rarer than diet generalists and were associated with open habitats, their populations may be especially affected by degradation of open habitats. More habitat-specialist bees were documented for open and forest/scrub habitats than for savanna/woodland habitats, consistent with bees responding to habitats of intermediate woody vegetation density, such as savannas, as ecotones rather than as distinct habitat types. Similarity of bee community composition, similarity of bee abundance, and similarity of bee richness between sites were not significantly related to proximity of sites to each other. Nestedness analysis indicated that species

  3. Using Field Data and GIS-Derived Variables to Model Occurrence of Williamson's Sapsucker Nesting Habitat at Multiple Spatial Scales.

    Directory of Open Access Journals (Sweden)

    Mark C Drever

    Full Text Available Williamson's sapsucker (Sphyrapicus thyroideus is a migratory woodpecker that breeds in mixed coniferous forests in western North America. In Canada, the range of this woodpecker is restricted to three small populations in southern British Columbia, precipitating a national listing as 'Endangered' in 2005, and the need to characterize critical habitat for its survival and recovery. We compared habitat attributes between Williamson's sapsucker nest territories and random points without nests or detections of this sapsucker as part of a resource selection analysis to identify the habitat features that best explain the probability of nest occurrence in two separate geographic regions in British Columbia. We compared the relative explanatory power of generalized linear models based on field-derived and Geographic Information System (GIS data within both a 225 m and 800 m radius of a nest or random point. The model based on field-derived variables explained the most variation in nest occurrence in the Okanagan-East Kootenay Region, whereas nest occurrence was best explained by GIS information at the 800 m scale in the Western Region. Probability of nest occurrence was strongly tied to densities of potential nest trees, which included open forests with very large (diameter at breast height, DBH, ≥57.5 cm western larch (Larix occidentalis trees in the Okanagan-East Kootenay Region, and very large ponderosa pine (Pinus ponderosa and large (DBH 17.5-57.5 cm trembling aspen (Populus tremuloides trees in the Western Region. Our results have the potential to guide identification and protection of critical habitat as required by the Species at Risk Act in Canada, and to better manage Williamson's sapsucker habitat overall in North America. In particular, management should focus on the maintenance and recruitment of very large western larch and ponderosa pine trees.

  4. What is the importance of open habitat in a predominantly closed forest area to the dung beetle (Coleoptera, Scarabaeinae assemblage?

    Directory of Open Access Journals (Sweden)

    Fábio C. Costa

    2013-09-01

    Full Text Available What is the importance of open habitat in a predominantly closed forest to the dung beetle assemblage? The Atlantic Forest in Brazil is one of the most highly disturbed ecosystems and is mainly represented by fragmented areas. However, in places where human disturbances have ceased, certain areas are showing a natural regeneration pattern. The aim of the present study was to determine how the dung beetle assemblage responds to distinct habitat structures in a fragment of Atlantic Forest. For such, open and closed forest areas were sampled in a fragment of the Atlantic Forest in the northeastern region of Brazil. Pitfall traps baited with excrement and carrion were used to collect the beetles. A total of 7,267 individuals belonging to 35 species were captured. Canthon chalybaeus and C. mutabilis were restricted to open areas. Nearly 90% of the individuals of C. aff. simulans and Deltochilum aff. irroratum were identified in these areas. A higher percentage (> 50% of Canthon staigi, Dichotomius aff. depressicolis and D. aff. sericeus occurred in closed areas. Abundance differed between areas, with higher values in closed areas. Richness was not influenced by the habitat structure. NMDS ordination exhibited the segregation of areas and ANOSIM confirmed that this variable explained the assemblage of dung beetle species. The findings of the present study validate that open areas are associated to more restrictive conditions, limiting a higher abundance of dung beetle. Although situated near preserved fragments, the studied open areas increase the heterogeneity of the general landscape.

  5. The free energies of partially open coronal magnetic fields

    Science.gov (United States)

    Low, B. C.; Smith, D. F.

    1993-01-01

    A simple model of the low corona is examined in terms of a static polytropic atmosphere in equilibrium with a global magnetic field. The question posed is whether magnetostatic states with partially open magnetic fields may contain magnetic energies in excess of those in fully open magnetic fields. Based on the analysis presented here, it is concluded that the cross-field electric currents in the pre-eruption corona are a viable source of the bulk of the energies in a mass ejection and its associated flare.

  6. Relationships of field habitat measurements, visual habitat indices, and land cover to benthic macroinvertebrates in urbanized streams of the Santa Clara Valley, California

    Science.gov (United States)

    Fend, S.V.; Carter, J.L.; Kearns, F.R.

    2005-01-01

    We evaluated several approaches for measuring natural and anthropogenic habitat characteristics to predict benthic macroinvertebrate assemblages over a range of urban intensity at 85 stream sites in the Santa Clara Valley, California. Land cover was summarized as percentage urban land cover and impervious area within upstream buffers and the upstream subwatersheds. Field measurements characterized water chemistry, channel slope, sediment, and riparian canopy. In . addition to applying the visual-based habitat assessment in U.S. Environmental Protection Agency's rapid bioassessment protocol, we developed a simplified urban habitat assessment index based on turbidity, fine sediment deposition, riparian condition, and channel modification. Natural and anthropogenic habitat variables covaried along longitudinal stream gradients and were highly correlated with elevation. At the scale of the entire watershed, benthic macroinvertebrate measures were equally correlated with variables expressing natural gradients and urbanization effects. When natural gradients were reduced by partitioning sites into ecoregion subsection groupings, habitat variables most highly correlated with macroinvertebrate measures differed between upland and valley floor site groups. Among the valley floor sites, channel slope and physical modification of channel and riparian habitats appeared more important than upstream land cover or water quality in determining macroinvertebrate richness and ordination scores. Among upland sites, effects of upstream reservoir releases on habitat quality appeared important. Rapid habitat evaluation methods appeared to be an effective method for describing habitat features important to benthic macroinvertebrates when adapted for the region and the disturbance of interest. ?? 2005 by the American Fisheries Society.

  7. Light-like tachyon condensation in Open String Field Theory

    CERN Document Server

    Hellerman, Simeon

    2008-01-01

    We use open string field theory to study the dynamics of unstable branes in the bosonic string theory, in the background of a generic linear dilaton. We find a simple exact solution describing a dynamical interpolation between the perturbative vacuum and the recently discovered nonperturbative tachyon vacuum. In our solution, the open string tachyon increases exponentially along a null direction, after which nonlinearities set in and cause the solution to asymptote to a static state. In particular, the wild oscillations of the open string fields which plague the time-like rolling tachyon solution are entirely absent. Our model thus represents the first example proving that the true tachyon vacuum of open string field theory can be realized as the endpoint of a dynamical transition from the perturbative vacuum.

  8. Decoupled taxonomic radiation and ecological expansion of open-habitat grasses in the Cenozoic of North America

    OpenAIRE

    Caroline A. E. Strömberg

    2005-01-01

    Because of a dearth of Cenozoic grass fossils, the timing of the taxonomic diversification of modern subclades within the grass family (Poaceae) and the rise to ecological dominance of open-habitat grasses remain obscure. Here, I present data from 99 Eocene to Miocene phytolith assemblages from the North American continental interior (Colorado, Nebraska, Wyoming, and Montana/Idaho), constituting the only high-resolution mid-Cenozoic record of grasses. Analyses of these assemblages show that o...

  9. Avian foods, foraging and habitat conservation in world rice fields

    Science.gov (United States)

    Stafford, J.D.; Kaminski, R.M.; Reinecke, K.J.

    2010-01-01

    Worldwide, rice (Oryza sativa) agriculture typically involves seasonal flooding and soil tillage, which provides a variety of microhabitats and potential food for birds. Water management in rice fields creates conditions ranging from saturated mud flats to shallow (seed mass from North America ranging from 66672 kg/ha. Although initially abundant after harvest, waste rice availability can be temporally limited. Few abundance estimates for other foods, such as vertebrate prey or forage vegetation, exist for rice fields. Outside North America, Europe and Japan, little is known about abundance and importance of any avian food in rice fields. Currently, flooding rice fields after harvest is the best known management practice to attract and benefit birds. Studies from North America indicate specific agricultural practices (e.g. burning stubble) may increase use and improve access to food resources. Evaluating and implementing management practices that are ecologically sustainable, increase food for birds and are agronomically beneficial should be global priorities to integrate rice production and avian conservation. Finally, land area devoted to rice agriculture appears to be stable in the USA, declining in China, and largely unquantified in many regions. Monitoring trends in riceland area may provide information to guide avian conservation planning in rice-agriculture ecosystems.

  10. Large optical field enhancement for nanotips with large opening angles

    Science.gov (United States)

    Thomas, Sebastian; Wachter, Georg; Lemell, Christoph; Burgdörfer, Joachim; Hommelhoff, Peter

    2015-06-01

    We theoretically investigate the dependence of the enhancement of optical near-fields at nanometric tips on the shape, size, and material of the tip. We confirm the strong dependence of the field enhancement factor on the radius of curvature. In addition, we find a surprisingly strong increase of field enhancement with increasing opening angle of the nanotips. For gold and tungsten nanotips in the experimentally relevant parameter range (radius of curvature ≥slant 5 nm at 800 nm laser wavelength), we obtain field enhancement factors of up to ∼ 35 for Au and ∼ 12 for W for large opening angles. We confirm this strong dependence on the opening angle for many other materials featuring a wide variety in their dielectric response. For dielectrics, the opening angle dependence is traced back to the electrostatic force of the induced surface charge at the tip shank. For metals, the plasmonic response strongly increases the field enhancement and shifts the maximum field enhancement to smaller opening angles.

  11. Fish Structural Habitat Surveys from Grays Reef National Marine Sanctuary Research Open Management Zones

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In situ visual surveys were conducted to generate size estimates and species composition of fish community habitat measurements (ledge height, macroalgal ht, sessile...

  12. Habitats on the NPS Martin Van Buren NHS and on the adjacent Open Space Institute land.

    Data.gov (United States)

    National Park Service, Department of the Interior — This shapefile is part of a project called Biological Surveys at the Martin Van Buren NHS conducted by Hudsonia Ltd. Habitats are mapped according to methodology in...

  13. A Field-Based Technique for Teaching about Habitat Fragmentation and Edge Effects

    Science.gov (United States)

    Resler, Lynn M.; Kolivras, Korine N.

    2009-01-01

    This article presents a field technique that exposes students to the indirect effects of habitat fragmentation on plant distributions through studying edge effects. This assignment, suited for students in an introductory biogeography or resource geography class, increases students' knowledge of basic biogeographic concepts such as environmental…

  14. Fish Habitat Improvement Projects in the Fifteenmile Creek and Trout Creek Basins of Central Oregon: Field Review and Management Recommendations.

    Energy Technology Data Exchange (ETDEWEB)

    Kauffman, J. Boone

    1993-07-01

    A field review of stream habitat improvement project sites in the lower Deschutes River Basin was conducted by riparian ecology, fisheries, and hydrology specialists. Habitat management objectives, limiting factors, project implementation, land use history, and other factors were discussed at each site. This information, in conjunction with the reviewer`s field inspections of portions of a particular habitat project, provided the basis for this report.

  15. The Phantom Term in Open String Field Theory

    CERN Document Server

    Erler, Theodore

    2012-01-01

    We show that given any two classical solutions in open string field theory and a singular gauge transformation relating them, it is possible to write the second solution as a gauge transformation of the first plus a singular, projector-like state which describes the shift in the open string background between the two solutions. This is the "phantom term." We give some applications in the computation of gauge invariant observables.

  16. Open archives within the field of environmental research

    OpenAIRE

    Alrøe, Hugo Fjelsted

    2003-01-01

    Presentation on the concept of open archives within the field of environmental research (and related areas such as agriculture, forestry and veterinary medicine ...). The presentation concerns open archives in general but relates to thes issue of public acces in accordance with the theme in the seminar - the UNECE Convention on Access to Information, Public Participation in Decision-making and Access to Justice in Environmental Matters (Aarhus Convention) ). The Organic Eprints archive is ...

  17. Open archives within the field of environmental research

    OpenAIRE

    Alrøe, Hugo Fjelsted

    2003-01-01

    Presentation on the concept of open archives within the field of environmental research (and related areas such as agriculture, forestry and veterinary medicine ...). The presentation concerns open archives in general but relates to thes issue of public acces in accordance with the theme in the seminar - the UNECE Convention on Access to Information, Public Participation in Decision-making and Access to Justice in Environmental Matters (Aarhus Convention) ). The Organic Eprints archive is ...

  18. Open Access Publishing in the Field of Medical Informatics.

    Science.gov (United States)

    Kuballa, Stefanie

    2017-05-01

    The open access paradigm has become an important approach in today's information and communication society. Funders and governments in different countries stipulate open access publications of funded research results. Medical informatics as part of the science, technology and medicine disciplines benefits from many research funds, such as National Institutes of Health in the US, Wellcome Trust in UK, German Research Foundation in Germany and many more. In this study an overview of the current open access programs and conditions of major journals in the field of medical informatics is presented. It was investigated whether there are suitable options and how they are shaped. Therefore all journals in Thomson Reuters Web of Science that were listed in the subject category "Medical Informatics" in 2014 were examined. An Internet research was conducted by investigating the journals' websites. It was reviewed whether journals offer an open access option with a subsequent check of conditions as for example the type of open access, the fees and the licensing. As a result all journals in the field of medical informatics that had an impact factor in 2014 offer an open access option. A predominantly consistent pricing range was determined with an average fee of 2.248 € and a median fee of 2.207 €. The height of a journals' open access fee did not correlate with the height of its Impact Factor. Hence, medical informatics journals have recognized the trend of open access publishing, though the vast majority of them are working with the hybrid method. Hybrid open access may however lead to problems in questions of double dipping and the often stipulated gold open access.

  19. String Field Theory Solution for Any Open String Background

    CERN Document Server

    Erler, Theodore

    2014-01-01

    We present an exact solution of open bosonic string field theory which can be used to describe any time-independent open string background. The solution generalizes an earlier construction of Kiermaier, Okawa, and Soler, and assumes the existence of boundary condition changing operators with nonsingular OPEs and vanishing conformal dimension. Our main observation is that boundary condition changing operators of this kind can describe nearly any open string background provided the background shift is accompanied by a timelike Wilson line of sufficient strength. As an application we analyze the tachyon lump describing the formation of a D$(p-1)$-brane in the string field theory of a D$p$-brane, for generic compactification radius. This not only provides a proof of Sen's second conjecture, but also gives explicit examples of higher energy solutions, confirming analytically that string field theory can "reverse" the direction of the worldsheet RG flow. We also find multiple D-brane solutions, demonstrating that s...

  20. Landscape models of brook trout abundance and distribution in lotic habitat with field validation

    Science.gov (United States)

    McKenna, James E.; Johnson, James H.

    2011-01-01

    Brook trout Salvelinus fontinalis are native fish in decline owing to environmental changes. Predictions of their potential distribution and a better understanding of their relationship to habitat conditions would enhance the management and conservation of this valuable species. We used over 7,800 brook trout observations throughout New York State and georeferenced, multiscale landscape condition data to develop four regionally specific artificial neural network models to predict brook trout abundance in rivers and streams. Land cover data provided a general signature of human activity, but other habitat variables were resistant to anthropogenic changes (i.e., changing on a geological time scale). The resulting models predict the potential for any stream to support brook trout. The models were validated by holding 20% of the data out as a test set and by comparison with additional field collections from a variety of habitat types. The models performed well, explaining more than 90% of data variability. Errors were often associated with small spatial displacements of predicted values. When compared with the additional field collections (39 sites), 92% of the predictions were off by only a single class from the field-observed abundances. Among “least-disturbed” field collection sites, all predictions were correct or off by a single abundance class, except for one where brown trout Salmo trutta were present. Other degrading factors were evident at most sites where brook trout were absent or less abundant than predicted. The most important habitat variables included landscape slope, stream and drainage network sizes, water temperature, and extent of forest cover. Predicted brook trout abundances were applied to all New York streams, providing a synoptic map of the distribution of brook trout habitat potential. These fish models set benchmarks of best potential for streams to support brook trout under broad-scale human influences and can assist with planning and

  1. Parallel multiphase field simulations with OpenPhase

    Science.gov (United States)

    Tegeler, Marvin; Shchyglo, Oleg; Kamachali, Reza Darvishi; Monas, Alexander; Steinbach, Ingo; Sutmann, Godehard

    2017-06-01

    The open-source software project OpenPhase allows the three-dimensional simulation of microstructural evolution using the multiphase field method. The core modules of OpenPhase and their implementation as well as their parallelization for a distributed-memory setting are presented. Especially communication and load-balancing strategies are discussed. Synchronization points are avoided by an increased halo-size, i.e. additional layers of ghost cells, which allow multiple stencil operations without data exchange. Load-balancing is considered via graph-partitioning and sub-domain decomposition. Results are presented for performance benchmarks as well as for a variety of applications, e.g. grain growth in polycrystalline materials, including a large number of phase fields as well as Mg-Al alloy solidification.

  2. Remote Laboratory and Animal Behaviour: An Interactive Open Field System

    Science.gov (United States)

    Fiore, Lorenzo; Ratti, Giovannino

    2007-01-01

    Remote laboratories can provide distant learners with practical acquisitions which would otherwise remain precluded. Our proposal here is a remote laboratory on a behavioural test (open field test), with the aim of introducing learners to the observation and analysis of stereotyped behaviour in animals. A real-time video of a mouse in an…

  3. Some Computations in Background Independent Open-String Field Theory

    CERN Document Server

    Witten, Edward

    1993-01-01

    Recently, background independent open-string field theory has been formally defined in the space of all two-dimensional world-sheet theories. In this paper, to make the construction more concrete, I compute the action for an off-shell tachyon field of a certain simple type. From the computation it emerges that, although the string field action does not coincide with the world-sheet (matter) partition function in general, these functions do coincide on shell. This can be demonstrated in general, as long as matter and ghosts are decoupled.

  4. Background Independent Open String Field Theory with Constant B field On the Annulus

    CERN Document Server

    Rashkov, R; Yang, Y

    2001-01-01

    We study Witten's background independent open-string field theory in the presence of a constant B-field at one loop level. The Green's function and the partition function with a constant B-field are evaluated for an annulus.

  5. Fragmented habitats of traditional fruit orchards are important for dead wood-dependent beetles associated with open canopy deciduous woodlands.

    Science.gov (United States)

    Horak, Jakub

    2014-06-01

    The conservation of traditional fruit orchards might be considered to be a fashion, and many people might find it difficult to accept that these artificial habitats can be significant for overall biodiversity. The main aim of this study was to identify possible roles of traditional fruit orchards for dead wood-dependent (saproxylic) beetles. The study was performed in the Central European landscape in the Czech Republic, which was historically covered by lowland sparse deciduous woodlands. Window traps were used to catch saproxylic beetles in 25 traditional fruit orchards. The species richness, as one of the best indicators of biodiversity, was positively driven by very high canopy openness and the rising proportion of deciduous woodlands in the matrix of the surrounding landscape. Due to the disappearance of natural and semi-natural habitats (i.e., sparse deciduous woodlands) of saproxylic beetles, orchards might complement the functions of suitable habitat fragments as the last biotic islands in the matrix of the cultural Central European landscape.

  6. Open Drug Discovery Toolkit (ODDT): a new open-source player in the drug discovery field.

    Science.gov (United States)

    Wójcikowski, Maciej; Zielenkiewicz, Piotr; Siedlecki, Pawel

    2015-01-01

    There has been huge progress in the open cheminformatics field in both methods and software development. Unfortunately, there has been little effort to unite those methods and software into one package. We here describe the Open Drug Discovery Toolkit (ODDT), which aims to fulfill the need for comprehensive and open source drug discovery software. The Open Drug Discovery Toolkit was developed as a free and open source tool for both computer aided drug discovery (CADD) developers and researchers. ODDT reimplements many state-of-the-art methods, such as machine learning scoring functions (RF-Score and NNScore) and wraps other external software to ease the process of developing CADD pipelines. ODDT is an out-of-the-box solution designed to be easily customizable and extensible. Therefore, users are strongly encouraged to extend it and develop new methods. We here present three use cases for ODDT in common tasks in computer-aided drug discovery. Open Drug Discovery Toolkit is released on a permissive 3-clause BSD license for both academic and industrial use. ODDT's source code, additional examples and documentation are available on GitHub (https://github.com/oddt/oddt).

  7. uvbybeta photometry of early type open cluster and field stars

    CERN Document Server

    Handler, G

    2011-01-01

    The beta Cephei stars and slowly pulsating B (SPB) stars are massive main sequence variables. The strength of their pulsational driving strongly depends on the opacity of iron-group elements. As many of those stars naturally occur in young open clusters, whose metallicities can be determined in several fundamental ways, it is logical to study the incidence of pulsation in several young open clusters. To provide the foundation for such an investigation, Str\\"omgren-Crawford uvbybeta photometry of open cluster target stars was carried out to determine effective temperatures, luminosities, and therefore cluster memberships. In the course of three observing runs, uvbybeta photometry for 168 target stars was acquired and transformed into the standard system by measurements of 117 standard stars. The list of target stars also included some known cluster and field beta Cephei stars, as well as beta Cephei and SPB candidates that are targets of the asteroseismic part of the Kepler satellite mission. The uvbybeta phot...

  8. The influence of mitigation on sage-grouse habitat selection within an energy development field.

    Directory of Open Access Journals (Sweden)

    Bradley C Fedy

    Full Text Available Growing global energy demands ensure the continued growth of energy development. Energy development in wildlife areas can significantly impact wildlife populations. Efforts to mitigate development impacts to wildlife are on-going, but the effectiveness of such efforts is seldom monitored or assessed. Greater sage-grouse (Centrocercus urophasianus are sensitive to energy development and likely serve as an effective umbrella species for other sagebrush-steppe obligate wildlife. We assessed the response of birds within an energy development area before and after the implementation of mitigation action. Additionally, we quantified changes in habitat distribution and abundance in pre- and post-mitigation landscapes. Sage-grouse avoidance of energy development at large spatial scales is well documented. We limited our research to directly within an energy development field in order to assess the influence of mitigation in close proximity to energy infrastructure. We used nest-location data (n = 488 within an energy development field to develop habitat selection models using logistic regression on data from 4 years of research prior to mitigation and for 4 years following the implementation of extensive mitigation efforts (e.g., decreased activity, buried powerlines. The post-mitigation habitat selection models indicated less avoidance of wells (well density β = 0.18 ± 0.08 than the pre-mitigation models (well density β = -0.09 ± 0.11. However, birds still avoided areas of high well density and nests were not found in areas with greater than 4 wells per km2 and the majority of nests (63% were located in areas with ≤ 1 well per km2. Several other model coefficients differed between the two time periods and indicated stronger selection for sagebrush (pre-mitigation β = 0.30 ± 0.09; post-mitigation β = 0.82 ± 0.08 and less avoidance of rugged terrain (pre-mitigation β = -0.35 ± 0.12; post-mitigation β = -0.05 ± 0.09. Mitigation efforts

  9. The influence of mitigation on sage-grouse habitat selection within an energy development field.

    Science.gov (United States)

    Fedy, Bradley C; Kirol, Christopher P; Sutphin, Andrew L; Maechtle, Thomas L

    2015-01-01

    Growing global energy demands ensure the continued growth of energy development. Energy development in wildlife areas can significantly impact wildlife populations. Efforts to mitigate development impacts to wildlife are on-going, but the effectiveness of such efforts is seldom monitored or assessed. Greater sage-grouse (Centrocercus urophasianus) are sensitive to energy development and likely serve as an effective umbrella species for other sagebrush-steppe obligate wildlife. We assessed the response of birds within an energy development area before and after the implementation of mitigation action. Additionally, we quantified changes in habitat distribution and abundance in pre- and post-mitigation landscapes. Sage-grouse avoidance of energy development at large spatial scales is well documented. We limited our research to directly within an energy development field in order to assess the influence of mitigation in close proximity to energy infrastructure. We used nest-location data (n = 488) within an energy development field to develop habitat selection models using logistic regression on data from 4 years of research prior to mitigation and for 4 years following the implementation of extensive mitigation efforts (e.g., decreased activity, buried powerlines). The post-mitigation habitat selection models indicated less avoidance of wells (well density β = 0.18 ± 0.08) than the pre-mitigation models (well density β = -0.09 ± 0.11). However, birds still avoided areas of high well density and nests were not found in areas with greater than 4 wells per km2 and the majority of nests (63%) were located in areas with ≤ 1 well per km2. Several other model coefficients differed between the two time periods and indicated stronger selection for sagebrush (pre-mitigation β = 0.30 ± 0.09; post-mitigation β = 0.82 ± 0.08) and less avoidance of rugged terrain (pre-mitigation β = -0.35 ± 0.12; post-mitigation β = -0.05 ± 0.09). Mitigation efforts implemented may

  10. Structure, food and shade attract juvenile coral reef fish to mangrove and seagrass habitats: a field experiment

    NARCIS (Netherlands)

    Verweij, M.C.; Nagelkerken, I.; Graaff, de D.; Peeters, M.; Bakker, E.J.; Velde, van der G.

    2006-01-01

    Mangroves and seagrass beds are considered nurseries for juvenile fish, but little experimental evidence exists to elucidate which factors make them attractive habitats. A multifactorial field experiment on the use of these habitats by juvenile reef fish and their behaviour was performed during dayt

  11. Structure, food and shade attract juvenile coral reef fish to mangrove and seagrass habitats: a field experiment.

    NARCIS (Netherlands)

    Verwey, M.C.; Nagelkerken, I.; Graaff, D. de; Peeters, M.; Bakker, E.J.; Velde, G. van der

    2006-01-01

    Mangroves and seagrass beds are considered nurseries for juvenile fish, but little experimental evidence exists to elucidate which factors make them attractive habitats. A multifactorial field experiment on the use of these habitats by juvenile reef fish and their behaviour was performed during dayt

  12. Higher Spins as Rolling Tachyons in Open String Field Theory

    CERN Document Server

    Polyakov, Dimitri

    2016-01-01

    We find a simple analytic solution in open string field theory which, in the on-shell limit, generates a tower of higher spin vertex operators in bosonic string theory. The solution is related to irregular off-shell vertex operators for Gaiotto states. The wavefunctions for the irregular vertex operators are described by equations following from the cubic effective action for generalized rolling tachyons, indicating that the evolution from flat to collective higher-spin background in string field theory occurs according to cosmological pattern. We discuss the relation between nonlocalities of the rolling tachyon action and those of higher spin interactions.

  13. Gauge Fixing of Modified Cubic Open Superstring Field Theory

    CERN Document Server

    Kohriki, Maiko; Kunitomo, Hiroshi

    2011-01-01

    The gauge-fixing problem of modified cubic open superstring field theory is discussed in detail both for the Ramond and Neveu-Schwarz sectors in the Batalin-Vilkovisky (BV) framework. We prove for the first time that the same form of action as the classical gauge-invariant one with the ghost-number constraint on the string field relaxed gives the master action satisfying the BV master equation. This is achieved by identifying independent component fields based on the analysis of the kernel structure of the inverse picture changing operator. The explicit gauge-fixing conditions for the component fields are discussed. In a kind of $b_0=0$ gauge, we explicitly obtain the NS propagator which has poles at the zeros of the Virasoro operator $L_0$.

  14. Nonlinear magnetic field transport in opening switch plasmas

    Science.gov (United States)

    Mason, R. J.; Auer, P. L.; Sudan, R. N.; Oliver, B. V.; Seyler, C. E.; Greenly, J. B.

    1993-04-01

    The nonlinear transport of magnetic field in collisionless plasmas, as present in the plasma opening switch (POS), using the implicit multifluid simulation code anthem [J. Comput. Phys. 71, 429 (1987)] is studied. The focus is on early time behavior in the electron-magnetohydrodynamic (EMHD) limit, with the ions fixed, and the electrons streaming as a fluid under the influence of ve×B Hall forces. Through simulation, magnetic penetration and magnetic exclusion waves are characterized, due to the Hall effect in the presence of transverse density gradients, and the interaction of these Hall waves with nonlinear diffusive disturbances from electron velocity advection, (veṡ∇)ve, is studied. It is shown how these mechanisms give rise to the anode magnetic insulation layer, central diffusion, and cathode potential hill structures seen in earlier opening switch plasmas studies.

  15. Field emission from open ended aluminum nitride nanotubes

    Science.gov (United States)

    Tondare, V. N.; Balasubramanian, C.; Shende, S. V.; Joag, D. S.; Godbole, V. P.; Bhoraskar, S. V.; Bhadbhade, M.

    2002-06-01

    This letter reports the field emission measurements from the nanotubes of aluminum nitride which were synthesized by gas phase condensation using the solid-vapor equilibria. A dc arc plasma reactor was used for producing the vapors of aluminum in a reactive nitrogen atmosphere. Nanoparticles and nanotubes of aluminum nitride were first characterized by transmission electron microscope and tube dimensions were found to be varying from 30 to 200 nm in diameter and 500 to 700 nm in length. These tubes were mixed with nanoparticles of size range between 5 and 200 nm in diameter. Tungsten tips coated with these nanoparticles and tubes were used as a field emitter. The field emission patterns display very interesting features consisting of sharp rings which were often found to change their shapes. The patterns are attributed to the open ended nanotubes of aluminum nitride. A few dot patterns corresponding to the nanoparticles were also seen to occur. The Fowler-Nordheim plots were seen to be nonlinear in nature, which reflects the semi-insulating behavior of the emitter. The field enhancement factor is estimated to be 34 500 indicating that the field enhancement due to the nanometric size of the emitter is an important cause for the observed emission.

  16. How to create successful Open Hardware projects - About White Rabbits and open fields

    CERN Document Server

    van der Bij, E; Lewis, J; Stana, T; Wlostowski, T; Gousiou, E; Serrano, J; Arruat, M; Lipinski, M M; Daniluk, G; Voumard, N; Cattin, M

    2013-01-01

    CERN's accelerator control group has embraced "Open Hardware" (OH) to facilitate peer review, avoid vendor lock-in and make support tasks scalable. A web-based tool for easing collaborative work was set up and the CERN OH Licence was created. New ADC, TDC, fine delay and carrier cards based on VITA and PCI-SIG standards were designed and drivers for Linux were written. Often industry was paid for developments, while quality and documentation was controlled by CERN. An innovative timing network was also developed with the OH paradigm. Industry now sells and supports these designs that find their way into new fields.

  17. Rapid diversification of falcons (Aves: Falconidae) due to expansion of open habitats in the Late Miocene.

    Science.gov (United States)

    Fuchs, Jérôme; Johnson, Jeff A; Mindell, David P

    2015-01-01

    Understanding how and why lineages diversify is central to understanding the origins of biological diversity. The avian family Falconidae (caracaras, forest-falcons, falcons) has an uneven distribution of species among multiple well-supported clades, and provides a useful system for testing hypotheses about diversification rate and correlation with environmental changes. We analyzed eight independent loci for 1-7 individuals from each of the 64 currently recognized Falconidae species, together with two fossil falconid temporal calibrations, to assess phylogeny, absolute divergence times and potential shifts in diversification rate. Our analyses supported similar diversification ages in the Early to Middle Miocene for the three traditional subfamilies, Herpetotherinae, Polyborinae and Falconinae. We estimated that divergences within the subfamily Falconinae began about 16mya and divergences within the most species-rich genus, Falco, including about 60% of all Falconidae species, began about 7.5mya. We found evidence for a significant increase in diversification rate at the basal phylogenetic node for the genus Falco, and the timing for this rate shift correlates generally with expansion of C4 grasslands beginning around the Miocene/Pliocene transition. Concomitantly, Falco lineages that are distributed primarily in grassland or savannah habitats, as opposed to woodlands, and exhibit migratory, as opposed to sedentary, behavior experienced a higher diversification rate. Published by Elsevier Inc.

  18. Determinants of field edge habitat restoration on farms in California's Sacramento Valley.

    Science.gov (United States)

    Garbach, Kelly; Long, Rachael Freeman

    2017-03-15

    Degradation and loss of biodiversity and ecosystem services pose major challenges in simplified agricultural landscapes. Consequently, best management practices to create or restore habitat areas on field edges and other marginal areas have received a great deal of recent attention and policy support. Despite this, remarkably little is known about how landholders (farmers and landowners) learn about field edge management practices and which factors facilitate, or hinder, adoption of field edge plantings. We surveyed 109 landholders in California's Sacramento Valley to determine drivers of adoption of field edge plantings. The results show the important influence of landholders' communication networks, which included two key roles: agencies that provide technical support and fellow landholders. The networks of landholders that adopted field edge plantings included both fellow landholders and agencies, whereas networks of non-adopters included either landholders or agencies. This pattern documents that social learning through peer-to-peer information exchange can serve as a complementary and reinforcing pathway with technical learning that is stimulated by traditional outreach and extension programs. Landholder experience with benefits and concerns associated with field edge plantings were also significant predictors of adoption. Our results suggest that technical learning, stimulated by outreach and extension, may provide critical and necessary support for broad-scale adoption of field-edge plantings, but that this alone may not be sufficient. Instead, outreach and extension efforts may need to be strategically expanded to incorporate peer-to-peer communication, which can provide critical information on benefits and concerns.

  19. Development of a spatially targeted field sampling technique for the southern cattle tick, Rhipicephalus microplus, by mapping white-tailed deer, Odocoileus virginianus, habitat in South Texas.

    Science.gov (United States)

    Phillips, Pamela L; Welch, John B; Kramer, Matthew

    2014-01-01

    The objective of our study was to determine whether satellite remote sensed data could be used to identify white-tailed deer, Odocoileus virginianus (Zimmerman) (Artiodactyla: Cervidae), habitat and target locations for sampling free-living larvae of the southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini) (Ixodida: Ixodidae) in South Texas. Two methods for mapping white-tailed deer habitat were used, an object-oriented method to identify closed canopies and waterways for deer movement and two vegetation indices: the Normalized Difference Vegetation Index and the Modified Soil Adjusted Vegetation Index to identify forage for deer. These two data sets of favorable white-tailed deer habitat were combined within a geographic information system to identify locations for sampling ticks. Larvae of R. (B.) microplus, were sampled in Zapata County, Texas, by walking transects with attached flannel panels to jeans. Although the data set and sampling period were limited, data analysis demonstrated that sampling of free-living larvae of R. (B.) microplus can be conducted in South Texas, and larvae were most abundant in areas that harbored O. virginianus. Spatial analysis of satellite imagery to classify white-tailed deer/southern cattle tick habitat proved efficacious and may be useful in directing sampling activities in the field. This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.

  20. Past and predicted future effects of housing growth on open space conservation opportunity areas and habitat connectivity around National Wildlife Refuges

    Science.gov (United States)

    Hamilton, Christopher M.; Baumann, Matthias; Pidgeon, Anna M.; Helmers, David P.; Thogmartin, Wayne E.; Heglund, Patricia J.; Radeloff, Volker C.

    2016-01-01

    ContextHousing growth can alter suitability of matrix habitats around protected areas, strongly affecting movements of organisms and, consequently, threatening connectivity of protected area networks.ObjectivesOur goal was to quantify distribution and growth of housing around the U.S. Fish and Wildlife Service National Wildlife Refuge System. This is important information for conservation planning, particularly given promotion of habitat connectivity as a climate change adaptation measure.MethodsWe quantified housing growth from 1940 to 2000 and projected future growth to 2030 within three distances from refuges, identifying very low housing density open space, “opportunity areas” (contiguous areas with habitat corridors within these opportunity areas in 2000.ResultsOur results indicated that the number and area of open space opportunity areas generally decreased with increasing distance from refuges and with the passage of time. Furthermore, total area in habitat corridors was much lower than in opportunity areas. In addition, the number of corridors sometimes exceeded number of opportunity areas as a result of habitat fragmentation, indicating corridors are likely vulnerable to land use change. Finally, regional differences were strong and indicated some refuges may have experienced so much housing growth already that they are effectively too isolated to adapt to climate change, while others may require extensive habitat restoration work.ConclusionsWildlife refuges are increasingly isolated by residential housing development, potentially constraining the movement of wildlife and, therefore, their ability to adapt to a changing climate.

  1. Using Field Data and GIS-Derived Variables to Model Occurrence of Williamson’s Sapsucker Nesting Habitat at Multiple Spatial Scales

    Science.gov (United States)

    2015-01-01

    Williamson's sapsucker (Sphyrapicus thyroideus) is a migratory woodpecker that breeds in mixed coniferous forests in western North America. In Canada, the range of this woodpecker is restricted to three small populations in southern British Columbia, precipitating a national listing as ‘Endangered’ in 2005, and the need to characterize critical habitat for its survival and recovery. We compared habitat attributes between Williamson’s sapsucker nest territories and random points without nests or detections of this sapsucker as part of a resource selection analysis to identify the habitat features that best explain the probability of nest occurrence in two separate geographic regions in British Columbia. We compared the relative explanatory power of generalized linear models based on field-derived and Geographic Information System (GIS) data within both a 225 m and 800 m radius of a nest or random point. The model based on field-derived variables explained the most variation in nest occurrence in the Okanagan-East Kootenay Region, whereas nest occurrence was best explained by GIS information at the 800 m scale in the Western Region. Probability of nest occurrence was strongly tied to densities of potential nest trees, which included open forests with very large (diameter at breast height, DBH, ≥57.5 cm) western larch (Larix occidentalis) trees in the Okanagan-East Kootenay Region, and very large ponderosa pine (Pinus ponderosa) and large (DBH 17.5–57.5 cm) trembling aspen (Populus tremuloides) trees in the Western Region. Our results have the potential to guide identification and protection of critical habitat as required by the Species at Risk Act in Canada, and to better manage Williamson’s sapsucker habitat overall in North America. In particular, management should focus on the maintenance and recruitment of very large western larch and ponderosa pine trees. PMID:26177286

  2. Habitat use by Oryzomys subflavus (Rodentia in an open shrubland formation in Restinga de Jurubatiba National Park, RJ, Brazil

    Directory of Open Access Journals (Sweden)

    H. G. Bergallo

    Full Text Available The Restinga de Jurubatiba has at least 10 plant formations, including open Clusia shrubland. This formation is composed of dense shrubs of many shapes and sizes, where Clusia hilariana is one of the most important plant species. Shrublands with Clusia (CC are poorer in plant species and less dense than shrublands without Clusia (SC. Oryzomys subflavus (Rodentia is the most abundant small mammal species in the open Clusia shrubland. We tested the hypothesis that the abundance of rodents would increase with the size of the patch and would be higher in SC shrublands. Rodents were captured, marked and released in three 780-m-long transects. At each capture site, we evaluated the shape of the shrubland patch, calculated the area and noted the category of the shrubland. Using ANCOVA, we ascertained whether the abundance of Oryzomys subflavus increased with the sampled area and used CC and SC shrublands differently. We also verified if the size of patches used by rodents varies in the same frequency as the size of available shrublands. Rodent abundance was found to increase significantly with the area. There were no differences in the size of the patches used by rodents and the frequency of the size of available patches. This finding indicates that O. subflavus, in the study area, is a generalist species that uses its habitat according to availability.

  3. Open and Closed String field theory interpreted in classical Algebraic Topology

    OpenAIRE

    Sullivan, Dennis

    2003-01-01

    There is an interpretation of open string field theory in algebraic topology. An interpretation of closed string field theory can be deduced from this open string theory to obtain as well the interpretation of open and closed string field theory combined.

  4. Open and Closed String field theory interpreted in classical Algebraic Topology

    OpenAIRE

    Sullivan, Dennis

    2003-01-01

    There is an interpretation of open string field theory in algebraic topology. An interpretation of closed string field theory can be deduced from this open string theory to obtain as well the interpretation of open and closed string field theory combined.

  5. Keldysh field theory for driven open quantum systems.

    Science.gov (United States)

    Sieberer, L M; Buchhold, M; Diehl, S

    2016-09-01

    Recent experimental developments in diverse areas-ranging from cold atomic gases to light-driven semiconductors to microcavity arrays-move systems into the focus which are located on the interface of quantum optics, many-body physics and statistical mechanics. They share in common that coherent and driven-dissipative quantum dynamics occur on an equal footing, creating genuine non-equilibrium scenarios without immediate counterpart in equilibrium condensed matter physics. This concerns both their non-thermal stationary states and their many-body time evolution. It is a challenge to theory to identify novel instances of universal emergent macroscopic phenomena, which are tied unambiguously and in an observable way to the microscopic drive conditions. In this review, we discuss some recent results in this direction. Moreover, we provide a systematic introduction to the open system Keldysh functional integral approach, which is the proper technical tool to accomplish a merger of quantum optics and many-body physics, and leverages the power of modern quantum field theory to driven open quantum systems.

  6. Keldysh field theory for driven open quantum systems

    Science.gov (United States)

    Sieberer, L. M.; Buchhold, M.; Diehl, S.

    2016-09-01

    Recent experimental developments in diverse areas—ranging from cold atomic gases to light-driven semiconductors to microcavity arrays—move systems into the focus which are located on the interface of quantum optics, many-body physics and statistical mechanics. They share in common that coherent and driven-dissipative quantum dynamics occur on an equal footing, creating genuine non-equilibrium scenarios without immediate counterpart in equilibrium condensed matter physics. This concerns both their non-thermal stationary states and their many-body time evolution. It is a challenge to theory to identify novel instances of universal emergent macroscopic phenomena, which are tied unambiguously and in an observable way to the microscopic drive conditions. In this review, we discuss some recent results in this direction. Moreover, we provide a systematic introduction to the open system Keldysh functional integral approach, which is the proper technical tool to accomplish a merger of quantum optics and many-body physics, and leverages the power of modern quantum field theory to driven open quantum systems.

  7. Linear b-Gauges for Open String Fields

    CERN Document Server

    Kiermaier, Michael; Zwiebach, Barton

    2008-01-01

    Motivated by Schnabl's gauge choice, we explore open string perturbation theory in gauges where a linear combination of antighost oscillators annihilates the string field. We find that in these linear b-gauges different gauge conditions are needed at different ghost numbers. We derive the full propagator and prove the formal properties which guarantee that the Feynman diagrams reproduce the correct on-shell amplitudes. We find that these properties can fail due to the need to regularize the propagator, and identify a large class of linear b-gauges for which they hold rigorously. In these gauges the propagator has a non-anomalous Schwinger representation and builds Riemann surfaces by adding strip-like domains. Projector-based gauges, like Schnabl's, are not in this class of gauges but we construct a family of regular linear b-gauges which interpolate between Siegel gauge and Schnabl gauge.

  8. Linear b-gauges for open string fields

    Science.gov (United States)

    Kiermaier, Michael; Sen, Ashoke; Zwiebach, Barton

    2008-03-01

    Motivated by Schnabl's gauge choice, we explore open string perturbation theory in gauges where a linear combination of antighost oscillators annihilates the string field. We find that in these linear b-gauges different gauge conditions are needed at different ghost numbers. We derive the full propagator and prove the formal properties which guarantee that the Feynman diagrams reproduce the correct on-shell amplitudes. We find that these properties can fail due to the need to regularize the propagator, and identify a large class of linear b-gauges for which they hold rigorously. In these gauges the propagator has a non-anomalous Schwinger representation and builds Riemann surfaces by adding strip-like domains. Projector-based gauges, like Schnabl's, are not in this class of gauges but we construct a family of regular linear b-gauges which interpolate between Siegel gauge and Schnabl gauge.

  9. Development and field validation of a regional, management-scale habitat model: A koala Phascolarctos cinereus case study.

    Science.gov (United States)

    Law, Bradley; Caccamo, Gabriele; Roe, Paul; Truskinger, Anthony; Brassil, Traecey; Gonsalves, Leroy; McConville, Anna; Stanton, Matthew

    2017-09-01

    Species distribution models have great potential to efficiently guide management for threatened species, especially for those that are rare or cryptic. We used MaxEnt to develop a regional-scale model for the koala Phascolarctos cinereus at a resolution (250 m) that could be used to guide management. To ensure the model was fit for purpose, we placed emphasis on validating the model using independently-collected field data. We reduced substantial spatial clustering of records in coastal urban areas using a 2-km spatial filter and by modeling separately two subregions separated by the 500-m elevational contour. A bias file was prepared that accounted for variable survey effort. Frequency of wildfire, soil type, floristics and elevation had the highest relative contribution to the model, while a number of other variables made minor contributions. The model was effective in discriminating different habitat suitability classes when compared with koala records not used in modeling. We validated the MaxEnt model at 65 ground-truth sites using independent data on koala occupancy (acoustic sampling) and habitat quality (browse tree availability). Koala bellows (n = 276) were analyzed in an occupancy modeling framework, while site habitat quality was indexed based on browse trees. Field validation demonstrated a linear increase in koala occupancy with higher modeled habitat suitability at ground-truth sites. Similarly, a site habitat quality index at ground-truth sites was correlated positively with modeled habitat suitability. The MaxEnt model provided a better fit to estimated koala occupancy than the site-based habitat quality index, probably because many variables were considered simultaneously by the model rather than just browse species. The positive relationship of the model with both site occupancy and habitat quality indicates that the model is fit for application at relevant management scales. Field-validated models of similar resolution would assist in guiding

  10. Inexpensive Open-Source Data Logging in the Field

    Science.gov (United States)

    Wickert, A. D.

    2013-12-01

    I present a general-purpose open-source field-capable data logger, which provides a mechanism to develop dense networks of inexpensive environmental sensors. This data logger was developed as a low-power variant of the Arduino open-source development system, and is named the ALog ("Arduino Logger") BottleLogger (it is slim enough to fit inside a Nalgene water bottle) version 1.0. It features an integrated high-precision real-time clock, SD card slot for high-volume data storage, and integrated power switching. The ALog can interface with sensors via six analog/digital pins, two digital pins, and one digital interrupt pin that can read event-based inputs, such as those from a tipping-bucket rain gauge. We have successfully tested the ALog BottleLogger with ultrasonic rangefinders (for water stage and snow accumulation and melt), temperature sensors, tipping-bucket rain gauges, soil moisture and water potential sensors, resistance-based tools to measure frost heave, and cameras that it triggers based on events. The source code for the ALog, including functions to interface with a a range of commercially-available sensors, is provided as an Arduino C++ library with example implementations. All schematics, circuit board layouts, and source code files are open-source and freely available under GNU GPL v3.0 and Creative Commons Attribution-ShareAlike 3.0 Unported licenses. Through this work, we hope to foster a community-driven movement to collect field environmental data on a budget that permits citizen-scientists and researchers from low-income countries to collect the same high-quality data as researchers in wealthy countries. These data can provide information about global change to managers, governments, scientists, and interested citizens worldwide. Watertight box with ALog BottleLogger data logger on the left and battery pack with 3 D cells on the right. Data can be collected for 3-5 years on one set of batteries.

  11. European Contribution to Human Aspect Investigations for Future Planetary Habitat Definition Studies: Field Tests at MDRS on Crew Time Utilisation and Habitat Interfaces

    Science.gov (United States)

    Pletser, Vladimir; Foing, Bernard

    2011-02-01

    Human factors are a dominant aspect in space missions, which may strongly influence work results and efficiency. To assess their impact on future long term space missions and to attempt a general quantification, the environmental and technical conditions to which astronauts may be confronted need to be reproduced as closely as possible. Among the stressors that occur during space missions, limited resources, limited social interactions, long term living and working in confined and isolated areas are among the most important for future planetary exploration. The European Space Agency (ESA) has a strong interest in obtaining data and insights in human aspects to prepare for future studies on the definition of future Lunar and Martian planetary habitats. In this frame, ESA's Directorate of Human Space Flight was associated to the EuroGeoMars campaign conducted by the Crews 76 and 77 in February 2009 in The Mars Society's `Mars Desert Research Station' (MDRS) in the Desert of Utah. The EuroGeoMars Campaign lasted 5 weeks and encompassed two groups of experiments, on human crew related aspects and field experiments in geology, biology and astronomy/astrophysics. The human crew related aspects covered (1) crew time organization in a planetary habitat, (2) an evaluation of the different functions and interfaces of this habitat, (3) an evaluation of man-machine interfaces of science and technical equipment. Several forms and questionnaires were filled in by all crew members: time and location evaluation sheets and two series of questionnaires. In addition, the crew participated in another on-going food study where the type of food was imposed and crew impressions were collected via questionnaires. The paper recalls the objectives of the human crew related experiments of the EuroGeoMars project and presents the first results of these field investigations. Some recommendations and lessons learnt will be presented and used as first inputs for future planetary habitat

  12. Variable stars in the field of open cluster NGC 2126

    Institute of Scientific and Technical Information of China (English)

    Shun-Fang Liu; Zhen-Yu Wu; Xiao-Bin Zhang; Jiang-Hua Wu; Jun Ma; Zhao-Ji Jiang; Jian-Sheng Chen; Xu Zhou

    2009-01-01

    We report the results of a time-series CCD photometric survey of variable stars in the field of open cluster NGC 2126. In about a one square degree field covering the cluster, a total of 21 variable candidates are detected during this survey, of which 16 are newly found. The periods, classifications and spectral types of 14 newly discovered variables are discussed, which consist of six eclipsing binary systems, three pulsating variable stars, three long period variables, one RS CVn star, and one W UMa or δ Scuti star. In addition, there are two variable candidates, the properties of which cannot be determined. By a method based on fitting observed spectral energy distributions of stars with theoretical ones, the membership probabilities and the fundamental parameters of this cluster are determined. As a result, five variables are probably members of NGC 2126. The fundamental parameters of this cluster are determined as: metallicity to be 0.008 Z , age log(t)=8.95, distance modulus (m - M)0 = 10.34 and reddening value E(B -V) = 0.55 mag.

  13. Impact of habitat diversification on arthropod communities: A study in the fields of Chinese cabbage, Brassica chinensis

    Institute of Scientific and Technical Information of China (English)

    HONG-JIAO CAI; ZHI-SHENG LI; MIN-SHENG YOU

    2007-01-01

    Field trials were carried out from June to August in 2004 at Wuyishan (Wuyi Mountains), Fujian province, China, to determine the effects of habitat diversification on arthropod communities. Two Chinese cabbage, Brassica chinensis, field 1 (Fl) and field 2 (F2) surrounded by diverse vegetable cultivars were selected, while a monoculture of Chinese cabbage served as the control field (CK). The results showed that: (i) when comparing insect abundance of each order between different habitats, significantly higher numbers of lepidopterous insects (39.76% from the each order) and lower densities of Hymenoptera (19.82%) were found in CK than in F1 and F2; (ii) compared with CK, F1 and F2 had a lower percentage of species richness and an abundance of herbivorous insects, but increased richness, abundance and biodiversity of predatory insects; (iii) no differences were observed in neutral insects' guild between different fields; and (iv) the dominant species for each guild depends on the habitat types and sampling dates. This study suggests that intercropping could conceivably be used in these habitats to increase the population of natural predators, thus achieving desirable and ecologically friendly results in vegetable fields.

  14. Integrating Open Access Geospatial Data to Map the Habitat Suitability of the Declining Corn Bunting (Miliaria calandra

    Directory of Open Access Journals (Sweden)

    Abdulhakim M. Abdi

    2013-09-01

    Full Text Available The efficacy of integrating open access geospatial data to produce habitat suitability maps for the corn bunting (Miliaria calandra was investigated. Landsat Enhanced Thematic Mapper Plus (ETM+, Shuttle Radar Topography Mission (SRTM and Corine (Coordination of Information on the Environment land cover data for the year 2000 (CLC2000 were processed to extract explanatory variables and divided into three sets; Satellite (ETM+, SRTM, CLC2000 and Combined (CLC2000 + Satellite. Presence-absence data for M. calandra, collected during structured surveys for the Catalan Breeding Bird Atlas, were provided by the Catalan Ornithological Institute. The dataset was partitioned into an equal number of presence and absence points by dividing it into five groups, each composed of 88 randomly selected presence points to match the number of absences. A logistic regression model was then built for each group. Models were evaluated using area under the curve (AUC of the receiver operating characteristic (ROC. Results of the five groups were averaged to produce mean Satellite, CLC2000 and Combined models. The mean AUC values were 0.69, 0.81 and 0.90 for the CLC2000, Satellite and the Combined model, respectively. The probability of M. calandra presence had the strongest positive correlation with land surface temperature, modified soil adjusted vegetation index, coefficient of variation for ETM+ band 5 and the fraction of non-irrigated arable land.

  15. Field Review of Fish Habitat Improvement Projects in the Grande Ronde and John Day River Basins of Eastern Oregon.

    Energy Technology Data Exchange (ETDEWEB)

    Beschta, Robert L.; Platts, William S.; Kauffman, J. Boone

    1991-10-01

    The restoration of vegetation adapted to riparian environments and the natural succession of riparian plant communities is necessary to recreate sustainable salmonid habitat and should be the focal point for fish habitat improvement programs. In mid-August of 1991, a field review of 16 Salmon habitat improvement sites in the Grande Ronde and John Day River Basins in Eastern Oregon was undertaken. The review team visited various types of fish habitat improvements associated with a wide range of reach types, geology, channel gradients, stream sizes, and vegetation communities. Enhancement objectives, limiting factors, landuse history, and other factors were discussed at each site. This information, in conjunction with the reviewer's field inspection of portions of a particular habitat improvement project, provided the basis for the following report. This report that follows is divided into four sections: (1) Recommendations, (2) Objectives, (3) Discussion and Conclusions, and (4) Site Comments. The first section represents a synthesis of major recommendations that were developed during this review. The remaining sections provide more detailed information and comments related to specific aspects of the field review.

  16. Influence of initial visual field sensitivity on visual field loss progression in open angle glaucoma

    Directory of Open Access Journals (Sweden)

    Hentova-Senćanić Paraskeva

    2012-01-01

    Full Text Available Introduction. It is important to know the risk factors for visual field defect progression in order to predict the future development of glaucoma. Objective. To investigate the influence of visual field initial sensitivity on the rate of visual field progression. Methods. A minimum of five visual fields were performed using computerized perimetry (Octopus over a mean follow- up 4-year period (48.85±17.84 months in 64 persons (114 eyes with primary open angle glaucoma. The rate of change of the whole central visual field and each of the seven regions of the field were measured by linear regression analysis of the mean sensitivity value versus time. Based on the slope of the regression line of visual field mean sensitivity over time the eyes were divided into two groups: the group with stable and the group with progressive visual field. The comparison of the mean sensitivity of the whole central visual field between the groups was performed using the Mann-Whitney U-test. The Spearman rang correlation coefficient and the Spearman probability p values were calculated to assess the mean sensitivity of the whole central visual field and of each visual field regions determined at the beginning of the study. Results. The initial mean sensitivity of the whole central visual field was lower in the group with progressive visual field (16.62±6.35 dB. Correlation between the initial mean sensitivity and the slope of the regression line was negative. The lowest mean sensitivity was in the group with progressive visual field in the upper temporal (13.73±7.35 dB, nasal (14.74±7.23 dB and upper nasal (15.03±7.75 dB regions. Conclusion. The lower mean sensitivity value of the visual field, especially in the nasal and upper nasal visual field regions, carries a greater risk for delayed progressive loss of the visual field in persons with glaucoma.

  17. Lack of response of an open-habitat ungulate to the presence of predator urine La falta de la respuesta de un ungulado de habitat abierto a la presencia de orina de depredadores

    Directory of Open Access Journals (Sweden)

    RONALD J SARNO

    2008-06-01

    Full Text Available The behavioral response of ungulates to the presence of odors associated with dangerous predators has received some attention, yet little is known about how predominantly open-habitat ungulates react to the presence of predator scents. We investigated the behavioral responses of a predominantly open-habitat ungulate, the guanaco, Lama guanicoe, when exposed to the urine of various predators. Guanacos only reacted to the urine of mountain lions (native predator, Puma concolor, in one trial. The lack of a response to predator urine may indicate that guanacos generally rely on visión more than olfaction for predator detection.La respuesta conductual de ungulados a la presencia de olores asociados a depredadores ha recibido algo de atención, pero aún se sabe poco sobre cuan predominantemente los ungulados de habitat abiertos reaccionan a la presencia de olores de depredadores. Examinamos las respuestas conductuales del guanaco, Lama guanicoe, cuando estos animales estaban expuestos a orina de varios depredadores. Los guanacos solo reaccionaron a la presencia de la orina del puma en uno de los ensayos. La ausencia de respuesta registrada podría indicar que los guanacos utilizan más la visión que el olfato para detectar a sus depredadores.

  18. Movement behaviour of the carabid beetle Pterostichus melanarius in crops and at a habitat interface explains patterns of population redistribution in the field.

    Directory of Open Access Journals (Sweden)

    Bas Allema

    Full Text Available Animals may respond to habitat quality and habitat edges and these responses may affect their distribution between habitats. We studied the movement behaviour of a ground-dwelling generalist predator, the carabid beetle Pterostichus melanarius (Illiger. We performed a mark-recapture experiment in two adjacent habitats; a large plot with oilseed radish (Raphanus sativus and a plot with rye (Secale cereale. We used model selection to identify a minimal model representing the mark-recapture data, and determine whether habitat-specific motility and boundary behaviour affected population redistribution. We determined movement characteristics of P. melanarius in laboratory arenas with the same plant species using video recording. Both the field and arena results showed preference behaviour of P. melanarius at the habitat interface. In the field, significantly more beetles moved from rye to oilseed radish than from radish to rye. In the arena, habitat entry was more frequent into oilseed radish than into rye. In the field, movement was best described by a Fokker-Planck diffusion model that contained preference behaviour at the interface and did not account for habitat specific motility. Likewise, motility calculated from movement data using the Patlak model was not different between habitats in the arena studies. Motility (m2 d-1 calculated from behavioural data resulted in estimates that were similar to those determined in the field. Thus individual behaviour explained population redistribution in the field qualitatively as well as quantitatively. The findings provide a basis for evaluating movement within and across habitats in complex agricultural landscapes with multiple habitats and habitat interfaces.

  19. Mosquitoes of field and forest: the scale of habitat segregation in a diverse mosquito assemblage.

    Science.gov (United States)

    Reiskind, M H; Griffin, R H; Janairo, M S; Hopperstad, K A

    2017-03-01

    Knowledge of the distribution of arthropod vectors across a landscape is important in determining the risk for vector-borne disease. This has been well explored for ticks, but not for mosquitoes, despite their importance in the transmission of a variety of pathogens. This study examined the importance of habitat, habitat edges, and the scale at which mosquito abundance and diversity vary in a rural landscape by trapping along transects from grassland areas into forest patches. Significant patterns of vector diversity and distinct mosquito assemblages across habitats were found. The scale of individual species' responses to habitat edges was often dramatic, with several species rarely straying even 10 m from the edge. The present results suggest blood-seeking mosquito species are faithful to certain habitats, which has consequences for patterns of vector diversity and risk for pathogen transmission. This implies that analysts of risk for pathogen transmission and foci of control, and developers of land management strategies should assess habitat at a finer scale than previously considered. © 2016 The Royal Entomological Society.

  20. Reconstruction of Open Solar Magnetic Flux and Interplanetary Magnetic Field in the 20Th Century

    Science.gov (United States)

    Ivanov, V. G.; Miletsky, E. V.

    2004-10-01

    We reconstruct mean magnitudes of the open solar magnetic field since 1915 using α magnetic synoptic charts of the Sun. The obtained series allows estimation of the interplanetary magnetic field. They also confirm the known conclusion about the secular increase of the solar open magnetic flux in the first half of the 20th century.

  1. Genetic data suggest a natural prehuman origin of open habitats in northern Madagascar and question the deforestation narrative in this region.

    Science.gov (United States)

    Quéméré, Erwan; Amelot, Xavier; Pierson, Julie; Crouau-Roy, Brigitte; Chikhi, Lounès

    2012-08-07

    The impact of climate change and anthropogenic deforestation on biodiversity is of growing concern worldwide. Disentangling how past anthropogenic and natural factors contributed to current biome distribution is thus a crucial issue to understand their complex interactions on wider time scales and to improve predictions and conservation strategies. This is particularly important in biodiversity hotspots, such as Madagascar, dominated by large open habitats whose origins are increasingly debated. Although a dominant narrative argues that Madagascar was originally entirely covered by woodlands, which were destroyed by humans, a number of recent studies have suggested that past climatic fluctuations played a major role in shaping current biome distributions well before humans arrived. Here, we address the question of the origin of open habitats in the Daraina region in northern Madagascar, using a multiproxy approach combining population genetics modeling and remote-sensing analyses. We show that (i) contrary to most regions of Madagascar, the forest cover in Daraina remained remarkably stable over the past 60 y, and (ii) the golden-crowned sifaka (Propithecus tattersalli), a forest-dwelling lemur, underwent a strong population contraction before the arrival of the first humans, hence excluding an anthropogenic cause. Prehuman Holocene droughts may have led to a significant increase of grasslands and a reduction in the species' habitat. This contradicts the prevailing narrative that land cover changes are necessarily anthropogenic in Madagascar but does not preclude the later role played by humans in other regions in which recent lemur bottlenecks have been observed.

  2. Energy Momentum Tensor and Marginal Deformations in Open String Field Theory

    CERN Document Server

    Sen, A

    2004-01-01

    Marginal boundary deformations in a two dimensional conformal field theory correspond to a family of classical solutions of the equations of motion of open string field theory. In this paper we develop a systematic method for relating the parameter labelling the marginal boundary deformation in the conformal field theory to the parameter labelling the classical solution in open string field theory. This is done by first constructing the energy-momentum tensor associated with the classical solution in open string field theory using Noether method, and then comparing this to the answer obtained in the conformal field theory by analysing the boundary state. We also use this method to demonstrate that in open string field theory the tachyon lump solution on a circle of radius larger than one has vanishing pressure along the circle direction, as is expected for a codimension one D-brane.

  3. HACKER ETHICS, FIELDS OF EXPERIMENTATION AND OPEN EDUCATION POSSIBILITIES

    Directory of Open Access Journals (Sweden)

    Ana Carolina Sampaio Coelho

    2016-12-01

    Full Text Available This paper proposes a discussion about open education, based on the concept of rhizome, articulated by Deleuze and Guattari in “A Thousand Plateaus”, and the "wandering lines", present in theFernand Deligny's cartography in "The arachnean and other texts". The paper explores how teachers can act as “Transformative Intellectuals” in the cyberculture context, opposing the banking model of education, adopting a critical perspective of teaching in the utilization of digital culture processes in their Pedagogical practices. In this regard, the discussion ends by suggesting a reflection about the potential of Open Educational Resources (OER and how they can be considered possibilities for wandering and deterritorialization in the context of Brazilian education.

  4. Open file data on the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Lippman, M.J.; Aguirre, B.D.; Wollenberg, H.A.; Witherspoon, P.A.

    1977-04-01

    Some of the unpublished data presently available on open file at the Lawrence Berkeley Laboratory are listed and described. In addition, in the files are a number of internal memoranda of the Commission Federal de Electricidad of Mexico (CFE) on chemical characteristics of the produced fluids and incrustations; published papers on Cerro Prieto and the geologic setting of the Salton Trough; and data on the hydrogeology of the Mexicali Valley. (MHR)

  5. Molecular gut-content analysis of a predator assemblage reveals the effect of habitat manipulation on biological control in the field

    Science.gov (United States)

    Despite growing evidence that habitat manipulation can alter predators’ impact on target prey consumption, few studies have directly examined the effect of habitat context on conservation biological control in the field. Because of contradictory evidence in the literature for the outcome of habita...

  6. $A_\\infty$ structure from the Berkovits formulation of open superstring field theory

    CERN Document Server

    Erler, Theodore; Takezaki, Tomoyuki

    2015-01-01

    By formulating open superstring field theory based on the small Hilbert space of the superconformal ghost sector, an action for the Neveu-Schwarz sector with an $A_\\infty$ structure has recently been constructed. We transform this action to the Wess-Zumino-Witten-like form and show that this theory is related to the Berkovits formulation of open superstring field theory based on the large Hilbert space by partial gauge fixing and field redefinition.

  7. Open-Axial-Field Magnet at ISR intersection I8

    CERN Multimedia

    1979-01-01

    This axial field spectrometer left the central collision region unobstructed in order to ease analysis of secondary particles emitted at large angle. The ISR circulating beams were passing through a hole in the magnet poles.

  8. Relative importance of current and past landscape structure and local habitat conditions for plant species richness in dry grassland-like forest openings.

    Science.gov (United States)

    Husáková, Iveta; Münzbergová, Zuzana

    2014-01-01

    In fragmented landscapes, plant species richness may depend not only on local habitat conditions but also on landscape structure. In addition, both present and past landscape structure may be important for species richness. There are, however, only a few studies that have investigated the relative importance of all of these factors. The aim of this study was to examine the effect of current and past landscape structures and habitat conditions on species richness at dry grassland-like forest openings in a forested landscape and to assess their relative importance for species richness. We analyzed information on past and present landscape structures using aerial photographs from 1938, 1973, 1988, 2000 and 2007. We calculated the area of each locality and its isolation in the present and in the past and the continuity of localities in GIS. At each locality, we recorded all vascular plant species (296 species in 110 forest openings) and information on abiotic conditions of the localities. We found that the current species richness of the forest openings was significantly determined by local habitat conditions as well as by landscape structure in the present and in the past. The highest species richness was observed on larger and more heterogeneous localities with rocks and shallow soils, which were already large and well connected to other localities in 1938. The changes in the landscape structure in the past can thus have strong effects on current species richness. Future studies attempting to understand determinants of species diversity in fragmented landscapes should also include data on past landscape structure, as it may in fact be more important than the present structure.

  9. When does diversity matter? Species functional diversity and ecosystem functioning across habitats and seasons in a field experiment.

    Science.gov (United States)

    Frainer, André; McKie, Brendan G; Malmqvist, Björn

    2014-03-01

    Despite ample experimental evidence indicating that biodiversity might be an important driver of ecosystem processes, its role in the functioning of real ecosystems remains unclear. In particular, the understanding of which aspects of biodiversity are most important for ecosystem functioning, their importance relative to other biotic and abiotic drivers, and the circumstances under which biodiversity is most likely to influence functioning in nature, is limited. We conducted a field study that focussed on a guild of insect detritivores in streams, in which we quantified variation in the process of leaf decomposition across two habitats (riffles and pools) and two seasons (autumn and spring). The study was conducted in six streams, and the same locations were sampled in the two seasons. With the aid of structural equations modelling, we assessed spatiotemporal variation in the roles of three key biotic drivers in this process: functional diversity, quantified based on a species trait matrix, consumer density and biomass. Our models also accounted for variability related to different litter resources, and other sources of biotic and abiotic variability among streams. All three of our focal biotic drivers influenced leaf decomposition, but none was important in all habitats and seasons. Functional diversity had contrasting effects on decomposition between habitats and seasons. A positive relationship was observed in pool habitats in spring, associated with high trait dispersion, whereas a negative relationship was observed in riffle habitats during autumn. Our results demonstrate that functional biodiversity can be as significant for functioning in natural ecosystems as other important biotic drivers. In particular, variation in the role of functional diversity between seasons highlights the importance of fluctuations in the relative abundances of traits for ecosystem process rates in real ecosystems.

  10. Wide Field CCD photometry around nine open clusters

    CERN Document Server

    Sharma, S; Ogura, K; Mito, H; Tarusawa, K; Sagar, R

    2006-01-01

    In this paper we study the evolution of core and corona of nine open clusters using the projected radial density profiles derived from homogeneous CCD photometric data obtained through the 105-cm Kiso Schmidt telescope. The age and galactocentric distance of the target clusters varies from 16 Myr to 2000 Myr and 9 kpcto 10.8 kpc respectively. Barring Be 62, which is young open cluster, other clusters show a uniform reddening across the cluster region. The reddening in Be 62varies from $E(B-V)_{min}$= 0.70 mag to $E(B-V)_{max}$= 1.00 mag. The corona of six of the clusters in the present sample is found to be elongated, however on the basis of the present sample it is not possible to establish any correlation between the age and shape of the core. The elongated core in the case of young cluster Be 62 may reflect the initial conditions in the parental molecular cloud. The other results of the present study are (i) Core radius `$r_c$' and corona size $`r_{cn}$'/cluster radius $`r_{cl}$' are linearly correlated. (...

  11. Comments on complete actions for open superstring field theory

    Science.gov (United States)

    Matsunaga, Hiroaki

    2016-11-01

    We clarify a Wess-Zumino-Witten-like structure including Ramond fields and propose one systematic way to construct gauge invariant actions: Wess-Zumino-Witten-like complete action S WZW. We show that Kunitomo-Okawa's action proposed in arXiv:1508.00366 can obtain a topological parameter dependence of Ramond fields and belongs to our WZW-like framework. In this framework, once a WZW-like functional {{A}}_{η }={{A}}_{η}[Ψ ] of a dynamical string field Ψ is constructed, we obtain one realization of S WZW[Ψ] parametrized by Ψ. On the basis of this way, we construct an action tilde{S} whose on-shell condition is equivalent to the Ramond equations of motion proposed in arXiv:1506.05774. Using these results, we provide the equivalence of two theories: arXiv:1508.00366 and arXiv:1506.05774.

  12. [OPEN FIELD BEHAVIOR AS A PREDICTIVE CRITERIA REFLECTING RATS CORTICOSTERONELEVEL BEFORE AND AFTER STRESS].

    Science.gov (United States)

    Umriukhin, P E; Grigorchuk, O S

    2015-12-01

    In the presented study we investigated the possibility to use the open field behavior data for prediction of corticosterone level in rat blood plasma before and after stress. It is shown that the most reliable open field behavior parameters, reflecting high probability of significant upregulation of corticosterone after 3 hours of immobilization, are the short latency of first movement and low locomotor activity during the test. Rats with high corticosterone at normal non-stress conditions are characterized by low locomotor activity and on the contrary long latency period for the entrance of open field center.

  13. Field Assessment of Gopher Tortoise Habitat at Camp Shelby, MS. Phase II: Overstory and Combined Assessments

    Science.gov (United States)

    2010-10-17

    in R. B. Burg, (ed.). North American Tortoises : Conservation and Ecology. U.S. Fish and Wildlife Service, Wildlife Research Report 12. Washington...Habitat selection and modification by Gopher Tortoise , Gopherus polyphemus, in Georgia longleaf pine forest. Chelonian Conservation and Biology 3...essen- tial to balance successful conservation and restoration of gopher tortoise populations on military installations while sustaining the

  14. A Field Survey of Window-Opening Behavior and Thermal Conditions in Apartments of Surabaya, Indonesia

    OpenAIRE

    Arethusa, Meita Tristida; Kubota, Tetsu; Nugroho, Agung Murti; Antaryama, I Gusti Ngurah; Ekasiwi, Sri Nastiti; Uno, Tomoko

    2014-01-01

    A field survey was conducted in apartments of Surabaya, Indonesia to investigate occupants’ window-opening behavior and their thermal conditions. A total of 347 households were interviewed and about 30 houses were covered for measurements of thermal conditions. It was seen that occupants in the naturally ventilated apartments tend to open windows or doors as much as possible at least during daytime for satisfying air flow and ventilation in particular. The average duration of opening windows/...

  15. Open and disturbed habitats support higher diversity of Syrphidae (Diptera)? A case study during three yr of sampling in a fragment of Araucaria forest in southern Brazil.

    Science.gov (United States)

    Souza, Jana Magaly Tesserolli de; Marinoni, Renato Contin; Marinoni, Luciane

    2014-01-01

    The diversity of hoverflies in five different habitats of the Parque Estadual de Vila Velha, Ponta Grossa, Paraná, Brazil, from September 1999 to August 2002 was studied. These five areas had been exposed to various types of anthropogenic disturbance at different times, which resulted in different stages of plant succession. In total, 2,841 specimens of 151 species of Syrphidae were collected using malaise traps. The highest species richness and abundance were found at the edge of the forest (Forest Edge), whereas the lowest was found in the most conserved areas. Evenness values increased along the succession gradient. The accumulation curve of new occurrences of syrphid species nearly approached an asymptote starting on the third month of the third year. Estimates of syrphid species richness using different methods indicated that between 155 and 288 species are found in the study area, according the Michaelis-Menten and the Chao2 estimators, respectively. The richness and abundance of representatives of the subfamily Syrphinae were higher in more open areas, where herbaceous plants predominate. Nineteen hoverfly species can be considered as environmental indicators, as they were collected exclusively or mainly in one of the defined habitat types. The degree of opening of the vegetation seems to be the factor determining the distribution of Syrphidae species, a conclusion based on the finding that grassy clearings in Araucaria Forests had more species. Hence, we conclude that, to become established, Syrphidae communities need conserved mosaic landscapes.

  16. A hybrid analytical model for open-circuit field calculation of multilayer interior permanent magnet machines

    Science.gov (United States)

    Zhang, Zhen; Xia, Changliang; Yan, Yan; Geng, Qiang; Shi, Tingna

    2017-08-01

    Due to the complicated rotor structure and nonlinear saturation of rotor bridges, it is difficult to build a fast and accurate analytical field calculation model for multilayer interior permanent magnet (IPM) machines. In this paper, a hybrid analytical model suitable for the open-circuit field calculation of multilayer IPM machines is proposed by coupling the magnetic equivalent circuit (MEC) method and the subdomain technique. In the proposed analytical model, the rotor magnetic field is calculated by the MEC method based on the Kirchhoff's law, while the field in the stator slot, slot opening and air-gap is calculated by subdomain technique based on the Maxwell's equation. To solve the whole field distribution of the multilayer IPM machines, the coupled boundary conditions on the rotor surface are deduced for the coupling of the rotor MEC and the analytical field distribution of the stator slot, slot opening and air-gap. The hybrid analytical model can be used to calculate the open-circuit air-gap field distribution, back electromotive force (EMF) and cogging torque of multilayer IPM machines. Compared with finite element analysis (FEA), it has the advantages of faster modeling, less computation source occupying and shorter time consuming, and meanwhile achieves the approximate accuracy. The analytical model is helpful and applicable for the open-circuit field calculation of multilayer IPM machines with any size and pole/slot number combination.

  17. An anchoring system for fish habitat structures: field technique, evaluation, and application.

    Science.gov (United States)

    Barbara L. Fontaine; Thomas D. Merritt

    1988-01-01

    Steel cable can be used to bind rocks and logs together to construct fish habitat structures in streams. Cables must be securely anchored if structures are to withstand floods. This paper describes a way to anchor cables into bedrock or ballast boulders. Anchor tensile strength ranged from 7,500 to 36,500 pounds and was related to type of resin and embedment depth....

  18. Maxent-directed field surveys identify new populations of narrowly endemic habitat specialists

    Directory of Open Access Journals (Sweden)

    Cody M. Rhoden

    2017-07-01

    Full Text Available Background Rare or narrowly endemic organisms are difficult to monitor and conserve when their total distribution and habitat preferences are incompletely known. One method employed in determining distributions of these organisms is species distribution modeling (SDM. Methods Using two species of narrowly endemic burrowing crayfish species as our study organisms, we sought to ground validate Maxent, a commonly used program to conduct SDMs. We used fine scale (30 m resolution rasters of pertinent habitat variables collected from historical museum records in 2014. We then ground validated the Maxent model in 2015 by randomly and equally sampling the output from the model. Results The Maxent models for both species of crayfish showed positive relationships between predicted relative occurrence rate and crayfish burrow abundance in both a Receiver Operating Characteristic and generalized linear model approach. The ground validation of Maxent led us to new populations and range extensions of both species of crayfish. Discussion We conclude that Maxent is a suitable tool for the discovery of new populations of narrowly endemic, rare habitat specialists and our technique may be used for other rare, endemic organisms.

  19. Maxent-directed field surveys identify new populations of narrowly endemic habitat specialists.

    Science.gov (United States)

    Rhoden, Cody M; Peterman, William E; Taylor, Christopher A

    2017-01-01

    Rare or narrowly endemic organisms are difficult to monitor and conserve when their total distribution and habitat preferences are incompletely known. One method employed in determining distributions of these organisms is species distribution modeling (SDM). Using two species of narrowly endemic burrowing crayfish species as our study organisms, we sought to ground validate Maxent, a commonly used program to conduct SDMs. We used fine scale (30 m) resolution rasters of pertinent habitat variables collected from historical museum records in 2014. We then ground validated the Maxent model in 2015 by randomly and equally sampling the output from the model. The Maxent models for both species of crayfish showed positive relationships between predicted relative occurrence rate and crayfish burrow abundance in both a Receiver Operating Characteristic and generalized linear model approach. The ground validation of Maxent led us to new populations and range extensions of both species of crayfish. We conclude that Maxent is a suitable tool for the discovery of new populations of narrowly endemic, rare habitat specialists and our technique may be used for other rare, endemic organisms.

  20. Open Effective Field Theories from Deeply Inelastic Reactions

    Science.gov (United States)

    Braaten, Eric; Hammer, Hans-Werner; Lepage, G. Peter

    2017-01-01

    Effective field theories have often been applied to systems with inelastic reactions that produce particles with large momenta outside the domain of validity of the effective theory. The effects of the deeply inelastic reactions have been taken into account in previous work by adding local anti-Hermitian terms to the effective Hamiltonian density. We show that an additional modification is required in equations governing the density matrix when multi-particle states are considered. We define an effective density matrix by tracing out states containing high-momentum particles, and show that it satisfies a Lindblad equation, with Lindblad operators determined by the anti-Hermitian terms in the effective Hamiltonian density. This research was supported in part by the Department of Energy, the National Science Foundation, and the Simons Foundation.

  1. Open Effective Field Theories from Deeply Inelastic Reactions

    CERN Document Server

    Braaten, Eric; Lepage, G Peter

    2016-01-01

    Effective field theories have often been applied to systems with deeply inelastic reactions that produce particles with large momenta outside the domain of validity of the effective theory. The effects of the deeply inelastic reactions have been taken into account in previous work by adding local anti-Hermitian terms to the effective Hamiltonian. Here we show that when multi-particle systems are considered, an additional modification is required in equations governing the density matrix. We define an effective density matrix by tracing over the states containing high-momentum particles, and show that it satisfies a Lindblad equation, with local Lindblad operators determined by the anti-Hermitian terms in the effective Hamiltonian density.

  2. NASA's Habitat Demonstration Unit (HDU) Pressurized Excursion Module (PEM) In-Field Demonstration at Desert RATS 2010

    Science.gov (United States)

    Tri, Terry O.; Kennedy, Kriss J.; Toups, Larry; Gill, Tracy R.; Howe, A. Scott

    2011-01-01

    This paper describes the construction, assembly, subsystem integration, transportation, and field testing operations associated with the Habitat Demonstration Unit (HDU) Pressurized Excursion Module (PEM) and discusses lessons learned. In a one-year period beginning summer 2009, a tightly scheduled design-develop-build process was utilized by a small NASA "tiger team" to produce the functional HDU-PEM prototype in time to participate in the 2010 Desert Research and Technology Studies (Desert RATS) field campaign. The process required the coordination of multiple teams, subcontractors, facility management and safety staff. It also required a well-choreographed material handling and transportation process to deliver the finished product from the NASA-Johnson Space Center facilities to the remote Arizona desert locations of the field test. Significant findings of this paper include the team s greater understanding of the HDU-PEM s many integration issues and the in-field training the team acquired which will enable the implementation of the next-generation of improvements and development of high-fidelity field operations in a harsh environment. The Desert RATS analog environment is being promoted by NASA as an efficient means to design, build, and integrate multiple technologies in a mission architecture context, with the eventual goal of evolving the technologies into robust flight hardware systems. The HDU-PEM in-field demonstration at Desert RATS 2010 provided a validation process for the integration team, which has already begun to retool for the 2011 field tests that require an adapted architecture.

  3. Magnetar giant flares in multipolar magnetic fields. I. Fully and partially open eruptions of flux ropes

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Lei [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030 (China); Yu, Cong, E-mail: muduri@shao.ac.cn, E-mail: cyu@ynao.ac.cn [Key Laboratory for the Structure and Evolution of Celestial Object, Chinese Academy of Sciences, Kunming 650011 (China)

    2014-04-01

    We propose a catastrophic eruption model for the enormous energy release of magnetars during giant flares, in which a toroidal and helically twisted flux rope is embedded within a force-free magnetosphere. The flux rope stays in stable equilibrium states initially and evolves quasi-statically. Upon the loss of equilibrium, the flux rope cannot sustain the stable equilibrium states and erupts catastrophically. During the process, the magnetic energy stored in the magnetosphere is rapidly released as the result of destabilization of global magnetic topology. The magnetospheric energy that could be accumulated is of vital importance for the outbursts of magnetars. We carefully establish the fully open fields and partially open fields for various boundary conditions at the magnetar surface and study the relevant energy thresholds. By investigating the magnetic energy accumulated at the critical catastrophic point, we find that it is possible to drive fully open eruptions for dipole-dominated background fields. Nevertheless, it is hard to generate fully open magnetic eruptions for multipolar background fields. Given the observational importance of the multipolar magnetic fields in the vicinity of the magnetar surface, it would be worthwhile to explore the possibility of the alternative eruption approach in multipolar background fields. Fortunately, we find that flux ropes may give rise to partially open eruptions in the multipolar fields, which involve only partial opening of background fields. The energy release fractions are greater for cases with central-arcaded multipoles than those with central-caved multipoles that emerged in background fields. Eruptions would fail only when the centrally caved multipoles become extremely strong.

  4. Modeling Critical Forest Habitat in the Southern Coal Fields of West Virginia

    Directory of Open Access Journals (Sweden)

    Aaron E. Maxwell

    2012-01-01

    Full Text Available Throughout the Central Appalachians of the United States resource extraction primarily from coal mining has contributed to the majority of the forest conversion to barren and reclaimed pasture and grass. The loss of forests in this ecoregion is significantly impacting biodiversity at a regional scale. Since not all forest stands provide equal levels of ecological functions, it is critical to identify and map existing forested resources by the benefits that accrue from their unique spatial patterns, watershed drainage, and landscape positions. We utilized spatial analysis and remote sensing techniques to define critical forest characteristics. The characteristics were defined by applying a forest fragmentation model utilizing morphological image analysis, defining headwater catchments at a 1 : 24,000 scale, and deriving ecological land units (ELUs from elevation data. Once critical forest values were calculated, it was possible to identify clusters of critical stands using spatial statistics. This spatially explicit method for modeling forest habitat could be implemented as a tool for assessing the impact of resource extraction and aid in the conservation of critical forest habitat throughout a landscape.

  5. Mapping rice field anopheline breeding habitats in Mali, West Africa, using Landsat ETM+ sensor data.

    Science.gov (United States)

    Diuk-Wasser, M A; Bagayoko, M; Sogoba, N; Dolo, G; Touré, M B; Traoré, S F; Taylor, C E

    2004-01-01

    The aim of this study was to determine whether remotely sensed data could be used to identify rice-related malaria vector breeding habitats in an irrigated rice growing area near Niono, Mali. Early stages of rice growth show peak larval production, but Landsat sensor data are often obstructed by clouds during the early part of the cropping cycle (rainy season). In this study, we examined whether a classification based on two Landsat Enhanced Thematic Mapper (ETM)+ scenes acquired in the middle of the season and at harvesting times could be used to map different land uses and rice planted at different times (cohorts), and to infer which rice growth stages were present earlier in the season. We performed a maximum likelihood supervised classification and evaluated the robustness of the classifications with the transformed divergence separability index, the kappa coefficient and confusion matrices. Rice was distinguished from other land uses with 98% accuracy and rice cohorts were discriminated with 84% accuracy (three classes) or 94% (two classes). Our study showed that optical remote sensing can reliably identify potential malaria mosquito breeding habitats from space. In the future, these 'crop landscape maps' could be used to investigate the relationship between cultivation practices and malaria transmission.

  6. Differential performance of tropical soda apple and its biological control agent Gratiana boliviana (Coleoptera: Chrysomelidae) in open and shaded habitats

    Science.gov (United States)

    The leaf feeding beetle Gratiana boliviana Spaeth has been released since 2003 in the southeastern United States for biological control of tropical soda apple, Solanum viarum Dunal. In Florida, G. boliviana can be found on tropical soda apple growing in open pastures as well as in shady wooded areas...

  7. Habitat eradication and cropland intensification may reduce parasitoid diversity and natural pest control services in annual crop fields

    Directory of Open Access Journals (Sweden)

    Deborah K. Letourneau

    2015-10-01

    Full Text Available Abstract California’s central coast differs from many agricultural areas in the U.S., which feature large tracts of monoculture production fields and relatively simple landscapes. Known as the nations salad bowl, and producing up to 90% of U.S. production of lettuces, broccoli and Brussels sprouts, this region is a mosaic of fresh vegetable fields, coastal meadow, chaparral shrubs, riparian and woodland habitat. We tested for relationships between the percent cover of crops, riparian and other natural landscape vegetation and the species richness of parasitic wasps and flies foraging in crops, such as broccoli, kale and cauliflower, and interpreted our results with respect to the decrease in natural habitat and increase in cropland cover prompted by a local microbial contamination event in 2006. Our key results are that: (1 as cropland cover in the landscape increased, fewer species of parasitoids were captured in the crop field, (2 parasitoid richness overall was positively associated with the amount of riparian and other natural vegetation in the surrounding 500m, (3 different groups of parasitoids were associated with unique types of natural vegetation, and (4 parasitism rates of sentinel cabbage aphid and cabbage looper pests were correlated with landscape vegetation features according to which parasitoids caused the mortality. Although individual species of parasitoids may thrive in landscapes that are predominantly short season crops, the robust associations found in this study across specialist and generalist parasitoids and different taxa (tachinid flies, ichneumon wasps, braconid wasps shows that recent food safety practices targeting removal of natural vegetation around vegetable fields in an attempt to eliminate wildlife may harm natural enemy communities and reduce ecosystem services. We argue that enhancing biological diversity is a key goal for transforming agroecosystems for future productivity, sustainability and public health.

  8. Of hopes, villains and Trojan horses – Open Access academic publishing and its battle fields

    OpenAIRE

    Šimukovič, Elena

    2015-01-01

    During its growth Open Access academic publishing has become a complex construction with sophisticated terms and modalities built into it. Multiple actors and interests involved make it to a value-laden field with different ideologies and tensions or even battles between them. However, taken-for-granted assumptions are rarely questioned or made explicit. Therefore, the overall aim of the PhD project is to capture the dynamics of the Open Access movement, the role it plays in anticipated chang...

  9. Performance Analysis of Field Orientation of Induction Motor Drive Under Open Gate of IGBT Fault

    Directory of Open Access Journals (Sweden)

    Zakaria Mohamed Salem

    2013-07-01

    Full Text Available This paper  presents a performance analysis of three phase induction motor drive system when fed from three-phase inverter with one IGBT open gate. The drive system is based on indirect rotor field oriented. The performance characteristics of the drive are investigated at healthy operating condition and at faulty condition with IGBT of upper phase leg is opened. The Total Harmonic Distortion of phases current in case opened IGBT are derived. The Simulation of the case study is carried out by using the Matlab/Simulink package on 1.1 kW, 220/380V, 50 Hz three phase induction motor.

  10. Emotionality in growing pigs: is the open field a valid test?

    Science.gov (United States)

    Donald, Ramona D; Healy, Susan D; Lawrence, Alistair B; Rutherford, Kenneth M D

    2011-10-24

    The ability to assess emotionality is important within animal welfare research. Yet, for farm animals, few tests of emotionality have been well validated. Here we investigated the construct validity of behavioural measures of pig emotionality in an open-field test by manipulating the experiences of pigs in three ways. In Experiment One (pharmacological manipulation), pigs pre-treated with Azaperone, a drug used to reduce stress in commercial pigs, were more active, spent more time exploring and vocalised less than control pigs. In Experiment Two (social manipulation), pigs that experienced the open-field arena with a familiar companion were also more exploratory, spent less time behaviourally idle, and were less vocal than controls although to a lesser degree than in Experiment One. In Experiment Three (novelty manipulation), pigs experiencing the open field for a second time were less active, explored less and vocalised less than they had done in the first exposure to the arena. A principal component analysis was conducted on data from all three trials. The first two components could be interpreted as relating to the form (cautious to exploratory) and magnitude (low to high arousal) of the emotional response to open-field testing. Based on these dimensions, in Experiment One, Azaperone pigs appeared to be less fearful than saline-treated controls. However, in Experiment Two, exposure to the arena with a conspecific did not affect the first two dimensions but did affect a third behavioural dimension, relating to oro-nasal exploration of the arena floor. In Experiment Three, repeat exposure altered the form but not the magnitude of emotional response: pigs were less exploratory in the second test. In conclusion, behavioural measures taken from pigs in an open-field test are sensitive to manipulations of their prior experience in a manner that suggests they reflect underlying emotionality. Behavioural measures taken during open-field exposure can be useful for making

  11. Analytic Solution for Tachyon Condensation in Berkovits' Open Superstring Field Theory

    CERN Document Server

    Erler, Theodore

    2013-01-01

    We present an analytic solution for tachyon condensation on a non-BPS D-brane in Berkovits' open superstring field theory. The solution is presented as a product of $2\\times 2$ matrices in two distinct $GL_2$ subgroups of the open string star algebra. All string fields needed for for computation of the nonpolynomial action can be derived in closed form, and the action produces the expected non-BPS D-brane tension in accordance with Sen's conjecture. We also comment on how D-brane charges may be encoded in the topology of the tachyon vacuum gauge orbit.

  12. Open channel flows of magnetic fluid induced by traveling magnetic field

    Science.gov (United States)

    Kuwahara, Takuya; Okubo, Masaaki; Yamane, Ryuichiro

    A theoretical analysis is made on laminar open channel flows of magnetic fluid induced by a non uniform traveling magnetic field which is applied with a stator of a single-sided linear induction motor. The induced flows are mainly in the direction opposite to the traveling direction of the magnetic field and in proportion to the phase velocity of the magnetic field. The velocity profiles are greatly affected by dimensionless wave number of the magnetic field. Near the bottom of the channel, the theoretical velocity distributions agree well with experimental ones which are measured with a laser optical fiber velocity sensor. However, the experimental velocity distributions become larger near the free surface.

  13. Assessment of Habitat Suitability Is Affected by Plant-Soil Feedback: Comparison of Field and Garden Experiment.

    Directory of Open Access Journals (Sweden)

    Lucie Hemrová

    Full Text Available Field translocation experiments (i.e., the introduction of seeds or seedlings of different species into different localities are commonly used to study habitat associations of species, as well as factors limiting species distributions and local abundances. Species planted or sown in sites where they naturally occur are expected to perform better or equally well compared to sites at which they do not occur or are rare. This, however, contrasts with the predictions of the Janzen-Connell hypothesis and commonly reported intraspecific negative plant-soil feedback. The few previous studies indicating poorer performance of plants at sites where they naturally occur did not explore the mechanisms behind this pattern.In this study, we used field translocation experiments established using both seeds and seedlings to study the determinants of local abundance of four dominant species in grasslands. To explore the possible effects of intraspecific negative plant-soil feedback on our results, we tested the effect of local species abundance on the performance of the plants in the field experiment. In addition, we set up a garden experiment to explore the intensity of intraspecific as well as interspecific feedback between the dominants used in the experiment.In some cases, the distribution and local abundances of the species were partly driven by habitat conditions at the sites, and species performed better at their own sites. However, the prevailing pattern was that the local dominants performed worse at sites where they naturally occur than at any other sites. Moreover, the success of plants in the field experiment was lower in the case of higher intraspecific abundance prior to experimental setup. In the garden feedback experiment, two of the species performed significantly worse in soils conditioned by their species than in soils conditioned by the other species. In addition, the performance of the plants was significantly correlated between the two

  14. The Size of Winter-Flooded Paddy Fields No Longer Limits the Foraging Habitat Use of the Endangered Crested Ibis (Nipponia nippon) in Winter.

    Science.gov (United States)

    Hu, Can-Shi; Song, Xiao; Ding, Chang-Qing; Ye, Yuan-Xing; Qing, Bao-Ping; Wang, Chao

    2016-08-01

    Paddy fields have traditionally been viewed as the key foraging habitats for the endangered crested ibis (Nipponia nippon). With the population of this species now increasing, its distribution has expanded to both lowland areas and outside the nature reserve. However, little is known about the current foraging habitat preferences of these birds, especially during winter. In this research, a total of 54 used sites and 50 unused sites were investigated during winter from December 2011 to January 2012. The results of logistic regression analysis indicate that soil softness, human disturbance, and distance to the nearest road were important factors. For the site plots of winter-flooded paddy fields, the birds prefer the paddy fields with higher coverage of vegetation, except softer foraging sites and lower human-related disturbance. In lowland areas, the size of winter-flooded paddy fields was not a limiting factor, due to the availability of other wetlands capable of providing abundant food. The micro-habitat characteristics were important indicators of foraging habitat quality rather than the size of winter-flooded paddy fields, and the food accessibility may play an important role in the process of foraging habitat use. We suggest the improvement of the foraging micro-habitat and environmental characteristics would be effective in ensuring the availability of food in the dispersed lowland areas. The local people still needed to be encouraged and compensated by their single-cropping cultivation, ploughed the paddy fields after harvesting and irrigated them with shallow water flooded in the original core areas of the nature reserve.

  15. Complete Action for Open Superstring Field Theory with Cyclic $A_\\infty$ Structure

    CERN Document Server

    Erler, Theodore; Takezaki, Tomoyuki

    2016-01-01

    We construct a gauge invariant action for the Neveu-Schwarz and Ramond sectors of open superstring field theory realizing a cyclic $A_\\infty$ structure, providing the first complete and fully explicit solution to the classical Batalin-Vilkovisky master equation in superstring field theory. We also demonstrate the equivalence of our action to the Wess-Zumino-Witten-based construction of Kunitomo and one of the authors.

  16. Complete action for open superstring field theory with cyclic A ∞ structure

    Science.gov (United States)

    Erler, Theodore; Okawa, Yuji; Takezaki, Tomoyuki

    2016-08-01

    We construct a gauge invariant action for the Neveu-Schwarz and Ramond sectors of open superstring field theory realizing a cyclic A ∞ structure, providing the first complete and fully explicit solution to the classical Batalin-Vilkovisky master equation in superstring field theory. We also demonstrate the equivalence of our action to the Wess-Zumino-Witten-based construction of Kunitomo and one of the authors.

  17. Tongues, bottles, and disconnected loops: The opening and closing of the interplanetary magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    McComas, D.J. [Los Alamos National Lab., NM (United States). Space and Atmospheric Sciences Group

    1994-06-01

    For years the field of Space Physics has had a problem, a really big problem for it occurs on the largest spatial scales in Space physics -- across the entire region under the Sun`s influence, the heliosphere. The problem is that the Sun appears to keep opening new magnetic flux into interplanetary space with no obvious way for this flux to close back off again. This state of affairs, without some previously unknown method for closing the open interplanetary magnetic field (IMF), leads to an ever growing amount of magnetic flux in interplanetary space: the magnetic flux catastrophe. Recently, considerable progress has been made in understanding why this catastrophic state is not the observed state of the heliosphere. This brief article paints the newly emerging picture of the opening and closing of the IMF and how these processes may account for the observed variation in the amount of magnetic flux in interplanetary space over the solar cycle.

  18. Magnetar Giant Flares in Multipolar Magnetic Fields --- I. Fully and Partially Open Eruptions of Flux Ropes

    CERN Document Server

    Huang, Lei

    2014-01-01

    We propose a catastrophic eruption model for magnetar's enormous energy release during giant flares, in which a toroidal and helically twisted flux rope is embedded within a force-free magnetosphere. The flux rope stays in stable equilibrium states initially and evolves quasi-statically. Upon the loss of equilibrium point is reached, the flux rope cannot sustain the stable equilibrium states and erupts catastrophically. During the process, the magnetic energy stored in the magnetosphere is rapidly released as the result of destabilization of global magnetic topology. The magnetospheric energy that could be accumulated is of vital importance for the outbursts of magnetars. We carefully establish the fully open fields and partially open fields for various boundary conditions at the magnetar surface and study the relevant energy thresholds. By investigating the magnetic energy accumulated at the critical catastrophic point, we find that it is possible to drive fully open eruptions for dipole dominated background...

  19. Exposure to a maternal cafeteria diet changes open-field behaviour in the developing offspring.

    Science.gov (United States)

    Speight, Abigail; Davey, William G; McKenna, Emily; Voigt, Jörg-Peter W

    2017-04-01

    The early postnatal period is a sensitive period in rodents as behavioural systems are developing and maturing during this time. However, little is currently known about the behavioural effects of feeding a hyper-energetic cafeteria diet (CD) during the lactational period when offspring behaviour is tested during early adolescence. To this end, 23days old offspring from dams (Wistar) fed on CD during lactation were tested in either the open-field or the elevated plus-maze for exploration and anxiety-related behaviour. On postnatal day 9, maternal behaviour and non-maternal behaviour of the dam was assessed. It was hypothesized that lactational CD feeding would reduce anxiety in the offspring. CD-fed dams had a higher energy intake, due to an overconsumption of sugars and fats. When offspring from these dams were exposed to the open field after weaning, their locomotor activity was increased. They entered the more aversive inner zone of the open-field after a shorter latency, made more entries into and spent more time in the inner zone. Anxiety-related behaviour was not affected upon exposure to the elevated plus maze, suggesting anxiolysis in the open-field only. Increased maternal licking/grooming behaviour could possibly contribute to the anxiolytic phenotype as observed in the offspring from the CD group. In conclusion, we demonstrate that lactational overfeeding impacts on the development of behaviour in the early adolescent rat. Copyright © 2016 ISDN. Published by Elsevier Ltd. All rights reserved.

  20. Automated TV based system for open field studies: Effects of methamphetamine

    NARCIS (Netherlands)

    Tanger, H.J.; Vanwersch, R.A.P.; Wolthuis, O.L.

    1978-01-01

    A method is described whereby open field behaviour of rats can be automatically registered using a TV camera, a video converter, an X-Y recorder and a papertape puncher. Use is made of the scanning properties of the TV camera to obtain the X and Y coordinates of the rat's position and to print this

  1. A Handheld Open-Field Infant Keratometer (An American Ophthalmological Society Thesis)

    Science.gov (United States)

    Miller, Joseph M.

    2010-01-01

    Purpose: To design and evaluate a new infant keratometer that incorporates an unobstructed view of the infant with both eyes (open-field design). Methods: The design of the open-field infant keratometer is presented, and details of its construction are given. The design incorporates a single-ring keratoscope for measurement of corneal astigmatism over a 4-mm region of the cornea and includes a rectangular grid target concentric within the ring to allow for the study of higher-order aberrations of the eye. In order to calibrate the lens and imaging system, a novel telecentric test object was constructed and used. The system was bench calibrated against steel ball bearings of known dimensions and evaluated for accuracy while being used in handheld mode in a group of 16 adult cooperative subjects. It was then evaluated for testability in a group of 10 infants and toddlers. Results: Results indicate that while the device achieved the goal of creating an open-field instrument containing a single-ring keratoscope with a concentric grid array for the study of higher-order aberrations, additional work is required to establish better control of the vertex distance. Conclusion: The handheld open-field infant keratometer demonstrates testability suitable for the study of infant corneal astigmatism. Use of collimated light sources in future iterations of the design must be incorporated in order to achieve the accuracy required for clinical investigation. PMID:21212850

  2. Semiochemical lures reduce emigration and enhance pest control services in open-field predator augmentation

    Science.gov (United States)

    Augmentation biocontrol is a commercially viable pest management tactic in enclosed glasshouse environments, but is far less effective in open-field agriculture where newly released enemies rapidly disperse from release sites. We tested the potential for behavior-modifying semiochemicals to increase...

  3. FieldTrip: Open source software for advanced analysis of MEG, EEG, and invasive electrophysiological data

    NARCIS (Netherlands)

    Oostenveld, R.; Fries, P.; Maris, E.; Schoffelen, J.M.

    2011-01-01

    This paper describes FieldTrip, an open source software package that we developed for the analysis of MEG, EEG, and other electrophysiological data. The software is implemented as a MATLAB toolbox and includes a complete set of consistent and user-friendly high-level functions that allow experimenta

  4. Field Trial of 40 Gb/s Optical Transport Network using Open WDM Interfaces

    DEFF Research Database (Denmark)

    Fagertun, Anna Manolova; Ruepp, Sarah Renée; Petersen, Martin Nordal;

    2013-01-01

    An experimental field-trail deployment of a 40Gb/s open WDM interface in an operational network is presented, in cross-carrier interconnection scenario. Practical challenges of integration and performance measures for both native and alien channels are outlined....

  5. The thermal behaviour of a threedimensional object placed in the open field

    NARCIS (Netherlands)

    Jacobs, P.A.M.

    1982-01-01

    In this thesis the energy-exchange between the atmosphere and a three-dimensional obstacle, placed in the open field is studied.This problem is part of a research program carried out by the infrared group of the Physics Laboratory TNO and is mainly concerned with the discrimination of objects and ba

  6. Variable stars in two open clusters within the Kepler/K2-Campaign-0 field

    DEFF Research Database (Denmark)

    Nardiello, D.; Bedin, L. R.; Nascimbeni, V.

    2015-01-01

    and exoplanetary transits in four fields containing five nearby open clusters spanning a broad range of ages. More in detail, our project will (1) constitute a preparatory survey for the High Accuracy Radial velocity Planet Searcher for the Northern hemisphere (HARPS-N) mounted at the Telescopio Nazionale Galileo...

  7. Antioxidant effects of nerolidol in mice hippocampus after open field test.

    Science.gov (United States)

    Nogueira Neto, José Damasceno; de Almeida, Antonia Amanda Cardoso; da Silva Oliveira, Johanssy; Dos Santos, Pauline Sousa; de Sousa, Damião Pergentino; de Freitas, Rivelilson Mendes

    2013-09-01

    The aim of this study was to evaluate the neuroprotective effects of nerolidol in mice hippocampus against oxidative stress in neuronal cells compared to ascorbic acid (positive control) as well as evaluated the nerolidol sedative effects by open field test compared to diazepam (positive control). Thirty minutes prior to behavioral observation on open field test, mice were intraperitoneally treated with vehicle, nerolidol (25, 50 and 75 mg/kg), diazepam (1 mg/kg) or ascorbic acid (250 mg/kg). To clarify the action mechanism of of nerolidol on oxidative stress in animals subjected to the open field test, Western blot analysis of Mn-superoxide dismutase and catalase in mice hippocampus were performed. In nerolidol group, there was a significant decrease in lipid peroxidation and nitrite levels when compared to negative control (vehicle). However, a significant increase was observed in superoxide dismutase and catalase activities in this group when compared to the other groups. Vehicle, diazepam, ascorbic acid and nerolidol groups did not affected Mn-superoxide dismutase, catalase mRNA or protein levels. Our findings strongly support the hypothesis that oxidative stress occurs in hippocampus. Nerolidol showed sedative effects in animals subjected to the open field test. Oxidative process plays a crucial role on neuronal pathological consequence, and implies that antioxidant effects could be achieved using this sesquiterpene.

  8. Heritability of feather pecking and open-field response of laying hens at two different ages

    NARCIS (Netherlands)

    Rodenburg, T.B.; Buitenhuis, A.J.; Ask, B.; Uitdehaag, K.A.; Koene, P.; Poel, van der J.J.; Bovenhuis, H.

    2003-01-01

    The objective of the current study was to estimate heritabilities. (h(2)) of feather pecking and open-field response of laying hens at two different ages. An F-2 cross, originating from a high and a low feather pecking line of laying hens, was used for the experiment. Each of the 630 birds of the F-

  9. In-Field Habitat Management to Optimize Pest Control of Novel Soil Communities in Agroecosystems

    Directory of Open Access Journals (Sweden)

    Kirsten A. Pearsons

    2017-08-01

    Full Text Available The challenge of managing agroecosystems on a landscape scale and the novel structure of soil communities in agroecosystems both provide reason to focus on in-field management practices, including cover crop adoption, reduced tillage, and judicial pesticide use, to promote soil community diversity. Belowground and epigeal arthropods, especially exotic generalist predators, play a significant role in controlling insect pests, weeds, and pathogens in agroecosystems. However, the preventative pest management tactics that dominate field-crop production in the United States do not promote biological control. In this review, we argue that by reducing disturbance, mitigating the effects of necessary field activities, and controlling pests within an Integrated Pest Management framework, farmers can facilitate the diversity and activity of native and exotic arthropod predators.

  10. In-Field Habitat Management to Optimize Pest Control of Novel Soil Communities in Agroecosystems.

    Science.gov (United States)

    Pearsons, Kirsten A; Tooker, John F

    2017-08-05

    The challenge of managing agroecosystems on a landscape scale and the novel structure of soil communities in agroecosystems both provide reason to focus on in-field management practices, including cover crop adoption, reduced tillage, and judicial pesticide use, to promote soil community diversity. Belowground and epigeal arthropods, especially exotic generalist predators, play a significant role in controlling insect pests, weeds, and pathogens in agroecosystems. However, the preventative pest management tactics that dominate field-crop production in the United States do not promote biological control. In this review, we argue that by reducing disturbance, mitigating the effects of necessary field activities, and controlling pests within an Integrated Pest Management framework, farmers can facilitate the diversity and activity of native and exotic arthropod predators.

  11. Widening access through openness in higher education in the developing world: A Bourdieusian field analysis of experiences from the National Open University of Nigeria

    Directory of Open Access Journals (Sweden)

    Felix Kayode Olakulehin

    2013-01-01

    Full Text Available Bourdieu has argued that higher education is a field that reproduces social inequality, thus complicating how openness widens access to higher education in the developing world. Drawing on the experiences of the National Open University of Nigeria (NOUN, this paper critically analyses and evaluates the rationale, approach, difficulties, opportunities, outcomes and benefits of NOUN’s experience in widening access to higher education in Nigeria using Bourdieu’s field theory. We argue that the success of efforts for openness in higher education in a developing world context involves steering the contradictory tensions of openness and access across competing policy and practice fields. We offer this theorisation as a future social theoretical agenda for reflexive research for improving the effectiveness of praxis to widen access through openness in higher education in the developing world.

  12. Exploratory behaviour in the open field test adapted for larval zebrafish: impact of environmental complexity.

    Science.gov (United States)

    Ahmad, Farooq; Richardson, Michael K

    2013-01-01

    This study aimed to develop and characterize a novel (standard) open field test adapted for larval zebrafish. We also developed and characterized a variant of the same assay consisting of a colour-enriched open field; this was used to assess the impact of environmental complexity on patterns of exploratory behaviours as well to determine natural colour preference/avoidance. We report the following main findings: (1) zebrafish larvae display characteristic patterns of exploratory behaviours in the standard open field, such as thigmotaxis/centre avoidance; (2) environmental complexity (i.e. presence of colours) differentially affects patterns of exploratory behaviours and greatly attenuates natural zone preference; (3) larvae displayed the ability to discriminate colours. As reported previously in adult zebrafish, larvae showed avoidance towards blue and black; however, in contrast to the reported adult behaviour, larvae displayed avoidance towards red. Avoidance towards yellow and preference for green and orange are shown for the first time, (4) compared to standard open field tests, exposure to the colour-enriched open field resulted in an enhanced expression of anxiety-like behaviours. To conclude, we not only developed and adapted a traditional rodent behavioural assay that serves as a gold standard in preclinical drug screening, but we also provide a version of the same test that affords the possibility to investigate the impact of environmental stress on behaviour in larval zebrafish while representing the first test for assessment of natural colour preference/avoidance in larval zebrafish. In the future, these assays will improve preclinical drug screening methodologies towards the goal to uncover novel drugs. This article is part of a Special Issue entitled: insert SI title.

  13. THE INTERACTION OF HABITAT FRAGMENTATION, PLANT, AND SMALL MAMMAL SUCCESSION IN AN OLD FIELD

    Science.gov (United States)

    We compared the density and spatial distribution of four small mammal species (Microtus ochrogaster, Peromyscus maniculatus, Sigmodon hispidus, and P. luecopus) along with general measures of an old field plant community across two successional phases (1984-1986 and 1994-1996) of...

  14. Singular surfaces in the open field line region of a diverted tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Reiman, A.

    1995-05-01

    The structure of the open field lines of a slightly nonaxisymmetric, poloidally diverted tokamak is explored by numerical integration of the field line equations for a simple model field. In practice, the nonaxisymmetry could be produced self-consistently by the nonlinear evolution of a free-boundary MHD mode, or it could be produced by field errors, or it could be imposed externally by design. In the presence of a nonaxisymmetric perturbation, the tokamak is shown to develop open field line regions of differing topology separated by singular surfaces. It is argued that the singular surfaces can be expected to play a role analogous to that of rational toroidal flux surfaces, in terms of constraining ideal MHD perturbations and thus constraining the free-energy that can be tapped by ideal MHD instabilities. The possibility of active control of free-boundary instabilities by means of currents driven on the open singular surfaces, which are directly accessible from the divertor plates, is discussed. Also discussed is the possibility of early detection of imminent disruptions through localized measurement of the singular surface currents.

  15. Real analytic solutions for marginal deformations in open superstring field theory

    Science.gov (United States)

    Okawa, Yuji

    2007-09-01

    We construct analytic solutions for marginal deformations satisfying the reality condition in open superstring field theory formulated by Berkovits when operator products made of the marginal operator and the associated superconformal primary field are regular. Our strategy is based on the recent observation by Erler that the problem of finding solutions for marginal deformations in open superstring field theory can be reduced to a problem in the bosonic theory of finding a finite gauge parameter for a certain pure-gauge configuration labeled by the parameter of the marginal deformation. We find a gauge transformation generated by a real gauge parameter which infinitesimally changes the deformation parameter and construct a finite gauge parameter by its path-ordered exponential. The resulting solution satisfies the reality condition by construction.

  16. Real analytic solutions for marginal deformations in open superstring field theory

    CERN Document Server

    Okawa, Yuji

    2007-01-01

    We construct analytic solutions for marginal deformations satisfying the reality condition in open superstring field theory formulated by Berkovits when operator products made of the marginal operator and the associated superconformal primary field are regular. Our strategy is based on the recent observation by Erler that the problem of finding solutions for marginal deformations in open superstring field theory can be reduced to a problem in the bosonic theory of finding a finite gauge parameter for a certain pure-gauge configuration labeled by the parameter of the marginal deformation. We find a gauge transformation generated by a real gauge parameter which infinitesimally changes the deformation parameter and construct a finite gauge parameter by its path-ordered exponential. The resulting solution satisfies the reality condition by construction.

  17. Connecting Solutions in Open String Field Theory with Singular Gauge Transformations

    CERN Document Server

    Erler, Theodore

    2012-01-01

    We show that any pair of classical solutions of open string field theory can be related by a formal gauge transformation defined by a gauge parameter $U$ without an inverse. We investigate how this observation can be used to construct new solutions. We find that a choice of gauge parameter consistently generates a new solution only if the BRST charge maps the image of $U$ into itself. When this occurs, we argue that $U$ naturally defines a star algebra projector which describes a surface of string connecting the boundary conformal field theories of the classical solutions related by $U$. We also note that singular gauge transformations give the solution space of open string field theory the structure of a category, and we comment on the physical interpretation of this observation.

  18. Frequency dependence of the acoustic field generated from a spherical cavity transducer with open ends

    Energy Technology Data Exchange (ETDEWEB)

    Li, Faqi; Zeng, Deping; He, Min; Wang, Zhibiao, E-mail: dzhang@nju.edu.cn, E-mail: wangzhibiao@haifu.com.cn [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, College of Biomedical Engineering, Chongqing Medical University, Chongqing 401121 (China); Song, Dan; Lei, Guangrong [National Engineering Research Center of Ultrasound Medicine, Chongqing 401121 (China); Lin, Zhou; Zhang, Dong, E-mail: dzhang@nju.edu.cn, E-mail: wangzhibiao@haifu.com.cn [Institute of Acoustics, Key Laboratory of Modern Acoustics, MOE, Nanjing University, Nanjing 210093 (China); Wu, Junru [Department of Physics, University of Vermont, Burlington, VT 05405 (United States)

    2015-12-15

    Resolution of high intensity focused ultrasound (HIFU) focusing is limited by the wave diffraction. We have developed a spherical cavity transducer with two open ends to improve the focusing precision without sacrificing the acoustic intensity (App Phys Lett 2013; 102: 204102). This work aims to theoretically and experimentally investigate the frequency dependence of the acoustic field generated from the spherical cavity transducer with two open ends. The device emits high intensity ultrasound at the frequency ranging from 420 to 470 kHz, and the acoustic field is measured by a fiber optic probe hydrophone. The measured results shows that the spherical cavity transducer provides high acoustic intensity for HIFU treatment only in its resonant modes, and a series of resonant frequencies can be choosen. Furthermore, a finite element model is developed to discuss the frequency dependence of the acoustic field. The numerical simulations coincide well with the measured results.

  19. Widening Access through Openness in Higher Education in the Developing World: A Bourdieusian Field Analysis of Experiences from the National Open University of Nigeria

    Science.gov (United States)

    Olakulehin, Felix Kayode; Singh, Gurmit

    2013-01-01

    Bourdieu has argued that higher education is a field that reproduces social inequality, thus complicating how openness widens access to higher education in the developing world. Drawing on the experiences of the National Open University of Nigeria (NOUN), this paper critically analyses and evaluates the rationale, approach, difficulties,…

  20. Predicting Scenarios for Successful Autodissemination of Pyriproxyfen by Malaria Vectors from Their Resting Sites to Aquatic Habitats; Description and Simulation Analysis of a Field-Parameterizable Model.

    Directory of Open Access Journals (Sweden)

    Samson S Kiware

    Full Text Available Large-cage experiments indicate pyriproxifen (PPF can be transferred from resting sites to aquatic habitats by Anopheles arabiensis--malaria vector mosquitoes to inhibit emergence of their own offspring. PPF coverage is amplified twice: (1 partial coverage of resting sites with PPF contamination results in far higher contamination coverage of adult mosquitoes because they are mobile and use numerous resting sites per gonotrophic cycle, and (2 even greater contamination coverage of aquatic habitats results from accumulation of PPF from multiple oviposition events.Deterministic mathematical models are described that use only field-measurable input parameters and capture the biological processes that mediate PPF autodissemination. Recent successes in large cages can be rationalized, and the plausibility of success under full field conditions can be evaluated a priori. The model also defines measurable properties of PPF delivery prototypes that may be optimized under controlled experimental conditions to maximize chances of success in full field trials. The most obvious flaw in this model is the endogenous relationship that inevitably occurs between the larval habitat coverage and the measured rate of oviposition into those habitats if the target mosquito species is used to mediate PPF transfer. However, this inconsistency also illustrates the potential advantages of using a different, non-target mosquito species for contamination at selected resting sites that shares the same aquatic habitats as the primary target. For autodissemination interventions to eliminate malaria transmission or vector populations during the dry season window of opportunity will require comprehensive contamination of the most challenging subset of aquatic habitats [Formula: see text] that persist or retain PPF activity (Ux for only one week [Formula: see text], where Ux = 7 days. To achieve >99% contamination coverage of these habitats will necessitate values for the

  1. Predicting Scenarios for Successful Autodissemination of Pyriproxyfen by Malaria Vectors from Their Resting Sites to Aquatic Habitats; Description and Simulation Analysis of a Field-Parameterizable Model

    Science.gov (United States)

    Kiware, Samson S.; Corliss, George; Merrill, Stephen; Lwetoijera, Dickson W.; Devine, Gregor; Majambere, Silas; Killeen, Gerry F.

    2015-01-01

    Background Large-cage experiments indicate pyriproxifen (PPF) can be transferred from resting sites to aquatic habitats by Anopheles arabiensis - malaria vector mosquitoes to inhibit emergence of their own offspring. PPF coverage is amplified twice: (1) partial coverage of resting sites with PPF contamination results in far higher contamination coverage of adult mosquitoes because they are mobile and use numerous resting sites per gonotrophic cycle, and (2) even greater contamination coverage of aquatic habitats results from accumulation of PPF from multiple oviposition events. Methods and Findings Deterministic mathematical models are described that use only field-measurable input parameters and capture the biological processes that mediate PPF autodissemination. Recent successes in large cages can be rationalized, and the plausibility of success under full field conditions can be evaluated a priori. The model also defines measurable properties of PPF delivery prototypes that may be optimized under controlled experimental conditions to maximize chances of success in full field trials. The most obvious flaw in this model is the endogenous relationship that inevitably occurs between the larval habitat coverage and the measured rate of oviposition into those habitats if the target mosquito species is used to mediate PPF transfer. However, this inconsistency also illustrates the potential advantages of using a different, non-target mosquito species for contamination at selected resting sites that shares the same aquatic habitats as the primary target. For autodissemination interventions to eliminate malaria transmission or vector populations during the dry season window of opportunity will require comprehensive contamination of the most challenging subset of aquatic habitats (Clx) that persist or retain PPF activity (Ux) for only one week (Clx→1, where Ux = 7 days). To achieve >99% contamination coverage of these habitats will necessitate values for the product of

  2. Evaluating the Applicability of Phi Coefficient in Indicating Habitat Preferences of Forest Soil Fauna Based on a Single Field Study in Subtropical China.

    Science.gov (United States)

    Cui, Yang; Wang, Silong; Yan, Shaokui

    2016-01-01

    Phi coefficient directly depends on the frequencies of occurrence of organisms and has been widely used in vegetation ecology to analyse the associations of organisms with site groups, providing a characterization of ecological preference, but its application in soil ecology remains rare. Based on a single field experiment, this study assessed the applicability of phi coefficient in indicating the habitat preferences of soil fauna, through comparing phi coefficient-induced results with those of ordination methods in charactering soil fauna-habitat(factors) relationships. Eight different habitats of soil fauna were implemented by reciprocal transfer of defaunated soil cores between two types of subtropical forests. Canonical correlation analysis (CCorA) showed that ecological patterns of fauna-habitat relationships and inter-fauna taxa relationships expressed, respectively, by phi coefficients and predicted abundances calculated from partial redundancy analysis (RDA), were extremely similar, and a highly significant relationship between the two datasets was observed (Pillai's trace statistic = 1.998, P = 0.007). In addition, highly positive correlations between phi coefficients and predicted abundances for Acari, Collembola, Nematode and Hemiptera were observed using linear regression analysis. Quantitative relationships between habitat preferences and soil chemical variables were also obtained by linear regression, which were analogous to the results displayed in a partial RDA biplot. Our results suggest that phi coefficient could be applicable on a local scale in evaluating habitat preferences of soil fauna at coarse taxonomic levels, and that the phi coefficient-induced information, such as ecological preferences and the associated quantitative relationships with habitat factors, will be largely complementary to the results of ordination methods. The application of phi coefficient in soil ecology may extend our knowledge about habitat preferences and distribution

  3. Evaluating the Applicability of Phi Coefficient in Indicating Habitat Preferences of Forest Soil Fauna Based on a Single Field Study in Subtropical China.

    Directory of Open Access Journals (Sweden)

    Yang Cui

    Full Text Available Phi coefficient directly depends on the frequencies of occurrence of organisms and has been widely used in vegetation ecology to analyse the associations of organisms with site groups, providing a characterization of ecological preference, but its application in soil ecology remains rare. Based on a single field experiment, this study assessed the applicability of phi coefficient in indicating the habitat preferences of soil fauna, through comparing phi coefficient-induced results with those of ordination methods in charactering soil fauna-habitat(factors relationships. Eight different habitats of soil fauna were implemented by reciprocal transfer of defaunated soil cores between two types of subtropical forests. Canonical correlation analysis (CCorA showed that ecological patterns of fauna-habitat relationships and inter-fauna taxa relationships expressed, respectively, by phi coefficients and predicted abundances calculated from partial redundancy analysis (RDA, were extremely similar, and a highly significant relationship between the two datasets was observed (Pillai's trace statistic = 1.998, P = 0.007. In addition, highly positive correlations between phi coefficients and predicted abundances for Acari, Collembola, Nematode and Hemiptera were observed using linear regression analysis. Quantitative relationships between habitat preferences and soil chemical variables were also obtained by linear regression, which were analogous to the results displayed in a partial RDA biplot. Our results suggest that phi coefficient could be applicable on a local scale in evaluating habitat preferences of soil fauna at coarse taxonomic levels, and that the phi coefficient-induced information, such as ecological preferences and the associated quantitative relationships with habitat factors, will be largely complementary to the results of ordination methods. The application of phi coefficient in soil ecology may extend our knowledge about habitat preferences

  4. Near-field wireless sensing of single and multiple open-ended micro coils

    Directory of Open Access Journals (Sweden)

    A. Yousaf

    2013-05-01

    Full Text Available In this work we present near-field wireless sensing of single and multiple open-ended micro coils using an electrically small loop antenna. Wirelessly characterized parameters of open-ended micro coils include its resonance frequency, quality factor and inductance. Moreover a wireless frequency-dependent analytical model was developed. Micro coil inductance was extracted from the wirelessly measured signal using a constraint-based least-squares approach. Wireless measurements and analytical fit of micro coils are in strong agreement which validates the analytical model. Finite element method (FEM simulations of the coupled system were done in COMSOL Multiphysics.

  5. On closed-string twist-field correlators and their open-string descendants

    CERN Document Server

    Anastasopoulos, Pascal; Richter, Robert

    2011-01-01

    In a recent paper we have proposed the possibility that the lightest massive string states could be identified with open strings living at intersections of D-branes forming small angles. In this note, we reconsider the relevant twist-field correlation functions and perform the analysis of the sub-dominant physical poles in the various channels. Our derivation is new in that it is based on the algebraic procedure for the construction of open string models starting from their closed-string `parents' rather than on the stress-tensor method. We also indicate possible generalizations and diverse applications of our approach.

  6. Closed String S-matrix Elements in Open String Field Theory

    CERN Document Server

    Garousi, M R; Garousi, Mohammad R

    2005-01-01

    Using the gauge invariant operators corresponding to on-shell closed string states in open string field theory, we study the tree level S-matrix element of two arbitrary closed string states, and the S-matrix element of one closed string and two open string states. By mapping the world-sheet of the amplitudes to the upper half z-plane, and by evaluating the correlators in the ghost parts, we show that the S-matrix elements are exactly identical to the corresponding disk level S-matrix elements in bosonic string theory.

  7. Closed String S-matrix Elements in Open String Field Theory

    Science.gov (United States)

    Garousi, Mohammad R.; Maktabdaran, G. R.

    2005-03-01

    We study the S-matrix elements of the gauge invariant operators corresponding to on-shell closed strings, in open string field theory. In particular, we calculate the tree level S-matrix element of two arbitrary closed strings, and the S-matrix element of one closed string and two open strings. By mapping the world-sheet of these amplitudes to the upper half z-plane, and by evaluating explicitly the correlators in the ghost part, we show that these S-matrix elements are exactly identical to the corresponding disk level S-matrix elements in perturbative string theory.

  8. Video-Based Electroshocking Platform to Identify Lamprey Ammocoete Habitats: Field Validation and New Discoveries in the Columbia River Basin

    Energy Technology Data Exchange (ETDEWEB)

    Arntzen, Evan V.; Mueller, Robert P.

    2017-05-04

    A deep water electroshocking platform (DEP), developed to characterize larval lampreys (ammocoetes) and associated habitat in depths up to 15 m, was recently tested in the field. The DEP samples 0.55 m2∙min-1 without requiring ammocoete transport to the surface. Searches were conducted at a known rearing location (mouth of the Wind River, WA) and at locations on the Cowlitz River, WA, where ammocoetes had not previously been found. At the mouth of the Wind River, video imaged ammocoetes ranged from 50 to 150 mm in water depths between 1.5 m and 4.5 m and were more common in sediments containing organic silt. Ammocoetes (n=137) were detected at 61% of locations sampled (summer) and 50% of the locations sampled (winter). Following the field verification, the DEP was used on the lower 11.7 km of the Cowlitz River, WA. Ammocoetes (n=41) were found with a detection rate of 26% at specific search locations. Cowlitz River sediment containing ammocoetes was also dominated by silt with organic material, often downstream of alluvial bars in water depths from 0.8 to 1.7 m. Test results indicated a high sampling efficiency, favorable detection rates, and little or no impact to ammocoetes and their surrounding benthic environments.

  9. Archaeobotanical reconstructions of field habitats and crops: the grange in Pomorzany near Kutno, 18th/19th c.

    Directory of Open Access Journals (Sweden)

    Koszałka Joanna

    2015-03-01

    Full Text Available The paper presents the results of research of plant macrofossils from the grain deposit deriving from the 18th/19th centuries. The analysed material included 24760 diaspores representing 73 taxa. The majority were cultivated cereal crop species, and there was also abundance of accompanying segetal weed species. About 95% of the gathered crop material was Secale cereale. Another important crop was Hordeum vulgare and there were also some remains of Avena sativa, Triticum aestivum, Fagopyrum esculentum. Cannabis sativa and Linum usitatissimum were found as well. Weeds competing with these crops were, among others, the following species: Agrostemma githago, Raphanus raphanistrum, Apera spica-venti, Bromus secalinus, Centaurea cyanus, Spergula arvensis, Thlaspi arvense, Viola arvensis/tricolor, Fallopia convolvulus, Polygonum persicaria, Mentha arvensis, Anthemis arvensis, Papaver rhoeas, Rumex acetosella, Scleranthus annuus, Aphanes arvensis, Setaria pumila, Setaria viridis/verticilata. Extremely large presence of wild plant diaspores in the material allowed conducting economic and environmental interpretations. Reconstruction methods applied, used primarily in the case of macroremains from granaries, were fully applicable to the analysed plant residues. Weed species composition in the analysed material showed that they were mostly typical for the main winter crop. Some amount of species typical for other habitats were also found and they probably came from the near-by rye field. The presence of perennial diaspores indicated that the field was probably set aside

  10. Piranti Lunak Pengujian Struktur Matematika Grup, Ring, Field Berbasis Osp (Open Source Program

    Directory of Open Access Journals (Sweden)

    Ngarap Im Manik

    2014-06-01

    Full Text Available This design of a computer software is a development and continuation of the software made on the previous research (2009/2010. However, this further research developed and expanded the scopes of testing more on the Siclic Group, Isomorphism Group, Semi Group, Sub Group and Abelian Group, Factor Ring, Sub Ring and Polynomial Ring; developed on the OSP (Open Source Program-based. The software was developed using the OSP-based language programming, such Java, so it is open and free to use for its users. This research succeeded to develop an open source software of Java program that can be used for testing specific mathematical Groups, such Ciclic Group, Isomorphism Group, Semi Group, Sub Group and Abelian Group, and Rings, Commutative Ring, Division Ring, Ideal Sub Ring, Ring Homomorphism, Ring Epimorphism and Fields. By the results, the software developed was able to test as same as the results from manual testing.

  11. Oval gradient coils for an open magnetic resonance imaging system with a vertical magnetic field

    Science.gov (United States)

    Matsuzawa, Koki; Abe, Mitsushi; Kose, Katsumi; Terada, Yasuhiko

    2017-05-01

    Existing open magnetic resonance imaging (MRI) systems use biplanar gradient coils for the spatial encoding of signals. We propose using novel oval gradient coils for an open vertical-field MRI. We designed oval gradients for a 0.3 T open MRI system and showed that such a system could outperform a traditional biplanar gradient system while maintaining adequate gradient homogeneity and subject accessibility. Such oval gradient coils would exhibit high efficiency, low inductance and resistance, and high switching capability. Although the designed oval Y and Z coils showed more heat dissipation and less cooling capability than biplanar coils with the same gap, they showed an efficient heat-dissipation path to the surrounding air, which would alleviate the heat problem. The performance of the designed oval-coil system was demonstrated experimentally by imaging a human hand.

  12. Geology and habitat of oil in Ras Budran field, Gulf of Suez, Egypt

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhary, L.R.; Taha, S.

    1987-05-01

    Deminex discovered the Ras Budran oil field in 1978. Discovery well EE 85-1 was drilled in about 140 ft of water, 4 km off the Sinai coast of the Gulf of Suez. Appraisal drilling (EE 85-2, 3, and 4 wells) confirmed the presence of a major field with an estimated 700 million bbl oil in place. The field, developed from three wellhead platforms, went on production in April 1983. To date, 20 development wells have been drilled. The Ras Budran structure at the deepest mappable seismic reflector, top Kareem (middle Miocene), is a broad northeast-southwest-trending anticlinal feature striking nearly at right angles to the main Gulf of Suez trend. At pre-Miocene producing horizons, the structure is complex and consists of a northeast-dipping flank (14-15) broken into several blocks by faults and limited to the south and west by major bounding faults. Oil is produced from three units of Nubian sandstone at a depth of 11,000 to 12,000 ft. The lower unit of Paleozoic age averages 10% porosity and up to 200 md in -situ permeability. The wells completed in this unit produce up to 2000 BOPD. In contrast, the sands of the upper two units of Lower Cretaceous age have a 15-20% porosity and up to 700 md permeability. The wells completed in these units produce 6000-8000 BOPD. The Ras Budran structure was primarily formed during the intra-Rudeis tectonic phase (lower Miocene). Migration of oil for accumulation in Ras Budran started late in the upper Miocene or Pliocene when the Santonian Brown Limestone and the Eocene Thebes Formation, the main source beds in the Gulf, reached the threshold of oil generation at a burial depth of about 10,000 ft (3000 m). At these depths, the organic matter in the source beds have a transformation ratio (0.10 to 0.15), increased yields of C15 + soluble organic matter and C15 + saturated hydrocarbons, a vitrinite reflectance of 0.62%, and a TTI value of 15.

  13. Habitat specialization through germination cueing

    DEFF Research Database (Denmark)

    Ten Brink, Dirk-Jan; Hendriksma, Harmen; Bruun, Hans Henrik

    2013-01-01

    This study examined the adaptive association between seed germination ecology and specialization to either forest or open habitats across a range of evolutionary lineages of seed plants, in order to test the hypotheses that (1) species' specialization to open vs. shaded habitats is consistently...

  14. Open Science CBS Neuroimaging Repository: Sharing ultra-high-field MR images of the brain.

    Science.gov (United States)

    Tardif, Christine Lucas; Schäfer, Andreas; Trampel, Robert; Villringer, Arno; Turner, Robert; Bazin, Pierre-Louis

    2016-01-01

    Magnetic resonance imaging at ultra high field opens the door to quantitative brain imaging at sub-millimeter isotropic resolutions. However, novel image processing tools to analyze these new rich datasets are lacking. In this article, we introduce the Open Science CBS Neuroimaging Repository: a unique repository of high-resolution and quantitative images acquired at 7 T. The motivation for this project is to increase interest for high-resolution and quantitative imaging and stimulate the development of image processing tools developed specifically for high-field data. Our growing repository currently includes datasets from MP2RAGE and multi-echo FLASH sequences from 28 and 20 healthy subjects respectively. These datasets represent the current state-of-the-art in in-vivo relaxometry at 7 T, and are now fully available to the entire neuroimaging community. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Gauge invariant observables from Takahashi-Tanimoto scalar solutions in open string field theory

    CERN Document Server

    Zeze, Syoji

    2014-01-01

    Using Maccaferri's formula, we derive new wedge based solutions of open string field theory. The solutions are gauge equivalent to the Takahashi-Tanimoto scalar solutions. The classical action and the gauge invariant overlap are evaluated analytically. We find a perturbative vacuum solution whose gauge invariant observables vanish. We also identify a tachyon vacuum solution whose gauge invariant observables are identical to those of the Erler-Schnabl solution.

  16. Management of whitefly-transmitted viruses in open-field production systems.

    Science.gov (United States)

    Lapidot, Moshe; Legg, James P; Wintermantel, William M; Polston, Jane E

    2014-01-01

    Whiteflies are a key pest of crops in open-field production throughout the tropics and subtropics. This is due in large part to the long and diverse list of devastating plant viruses transmitted by these vectors. Open-field production provides many challenges to manage these viruses and in many cases adequate management has not been possible. Diseases caused by whitefly-transmitted viruses have become limiting factors in open-field production of a wide range of crops, i.e., bean golden mosaic disease in beans, tomato yellow leaf curl disease in tomato, cassava mosaic disease and cassava brown streak disease in cassava, and cotton leaf crumple disease in cotton. While host resistance has proven to be the most cost-effective management solution, few examples of host resistance have been developed to date. The main strategy to limit the incidence of virus-infected plants has been the application of insecticides to reduce vector populations aided to some extent by the use of selected cultural practices. However, due to concerns about the effect of insecticides on pollinators, consumer demand for reduced pesticide use, and the ability of the whitefly vectors to develop insecticide-resistance, there is a growing need to develop and deploy strategies that do not rely on insecticides. The reduction in pesticide use will greatly increase the need for genetic resistance to more viruses in more crop plants. Resistance combined with selected IPM strategies could become a viable means to increase yields in crops produced in open fields despite the presence of whitefly-transmitted viruses.

  17. Chronic Toxoplasma gondii in Nurr1-null heterozygous mice exacerbates elevated open field activity.

    Directory of Open Access Journals (Sweden)

    Jeffrey B Eells

    Full Text Available Latent infection with Toxoplasma gondii is common in humans (approximately 30% of the global population and is a significant risk factor for schizophrenia. Since prevalence of T. gondii infection is far greater than prevalence of schizophrenia (0.5-1%, genetic risk factors are likely also necessary to contribute to schizophrenia. To test this concept in an animal model, Nurr1-null heterozygous (+/- mice and wild-type (+/+ mice were evaluate using an emergence test, activity in an open field and with a novel object, response to bobcat urine and prepulse inhibition of the acoustic startle response (PPI prior to and 6 weeks after infection with T. gondii. In the emergence test, T. gondii infection significantly decreased the amount of time spent in the cylinder. Toxoplasma gondii infection significantly elevated open field activity in both +/+ and +/- mice but this increase was significantly exacerbated in +/- mice. T. gondii infection reduced PPI in male +/- mice but this was not statistically significant. Aversion to bobcat urine was abolished by T. gondii infection in +/+ mice. In female +/- mice, aversion to bobcat urine remained after T. gondii infection while the male +/- mice showed no aversion to bobcat urine. Antibody titers of infected mice were a critical variable associated with changes in open field activity, such that an inverted U shaped relationship existed between antibody titers and the percent change in open field activity with a significant increase in activity at low and medium antibody titers but no effect at high antibody titers. These data demonstrate that the Nurr1 +/- genotype predisposes mice to T. gondii-induced alterations in behaviors that involve dopamine neurotransmission and are associated with symptoms of schizophrenia. We propose that these alterations in murine behavior were due to further exacerbation of the altered dopamine neurotransmission in Nurr1 +/- mice.

  18. Ambipolar transport via trapped-electron whistler instability along open magnetic field lines.

    Science.gov (United States)

    Guo, Zehua; Tang, Xian-Zhu

    2012-09-28

    An open field line plasma is bounded by a chamber wall which intercepts the magnetic field. Steady state requires an upstream plasma source balancing the particle loss to the boundary. In cases where the electrons have a long mean free path, ambipolarity in parallel transport critically depends on collisionless detrapping of the electrons via wave-particle interaction. The trapped-electron whistler instability, whose nonlinear saturation produces a spectrum of whistler waves that is responsible for the electron detrapping flux, is shown to be an unusually robust kinetic instability, which is essential to the universality of the ambipolar constraint in plasma transport.

  19. Simulation of future global warming scenarios in rice paddies with an open-field warming facility

    Directory of Open Access Journals (Sweden)

    Rehmani Muhammad

    2011-12-01

    Full Text Available Abstract To simulate expected future global warming, hexagonal arrays of infrared heaters have previously been used to warm open-field canopies of upland crops such as wheat. Through the use of concrete-anchored posts, improved software, overhead wires, extensive grounding, and monitoring with a thermal camera, the technology was safely and reliably extended to paddy rice fields. The system maintained canopy temperature increases within 0.5°C of daytime and nighttime set-point differences of 1.3 and 2.7°C 67% of the time.

  20. Higher spin modes as rolling tachyons in open string field theory

    Science.gov (United States)

    Polyakov, Dimitri

    2016-09-01

    We find a simple analytic solution in open string field theory which, in the on-shell limit, generates a tower of higher-spin vertex operators in bosonic string theory. The solution is related to irregular off-shell vertex operators for Gaiotto states. The wave functions for the irregular vertex operators are described by equations following from the cubic effective action for generalized rolling tachyons, indicating that the evolution from flat to collective higher-spin background in string field theory occurs according to cosmological pattern. We discuss the relation between nonlocalities of the rolling tachyon action and those of higher-spin interactions.

  1. Gap opening and tuning in single-layer graphene with combined electric and magnetic field modulation

    Institute of Scientific and Technical Information of China (English)

    Lin Xin; Wang Hai-Long; Pan Hui; Xu Huai-Zhe

    2011-01-01

    The energy band structure of single-layer graphene under one-dimensional electric and magnetic field modulation is theoretically investigated. The criterion for bandgap opening at the Dirac point is analytically derived with a two-fold degeneracy second-order perturbation method. It is shown that a direct or an indirect bandgap semiconductor could be realized in a single-layer graphene under some specific configurations of the electric and magnetic field arrangement. Due to the bandgap generated in the single-layer graphene, the Klein tunneling observed in pristine graphene is completely suppressed.

  2. An Application-oriented Open Software Platform for Multi-purpose Field Robotics

    DEFF Research Database (Denmark)

    Jensen, Kjeld

    Field robotics has become an increasingly active research area in the past 50 years, and there is great potential in using autonomous field robots to perform precision tasks in biological production and related applications. But the products available on the market today are limited to small robots...... that solve simple tasks such as mowing, and automatic tractor steering that navigates through a planned route under the supervision of an operator. The outdoor environment in which the robot operates is often very complex. This places great demands on the robot's ability to perceive the environment and based...... open software platform for multi-purpose field robotics will reduce the resources required for experimental research considerably due to reuse of existing work across projects and robotic platforms. This thesis describes the FroboMind field robot software platform developed in this work and presents...

  3. An Application-oriented Open Software Platform for Multi-purpose Field Robotics

    DEFF Research Database (Denmark)

    Jensen, Kjeld

    Field robotics has become an increasingly active research area in the past 50 years, and there is great potential in using autonomous field robots to perform precision tasks in biological production and related applications. But the products available on the market today are limited to small robots...... on this behave in a way that is appropriate and productive with respect to the given task while being safe for nearby people, animals and objects. Researchers are challenged by the considerable resources required to develop robot software capable of supporting experiments in such a complex perception...... open software platform for multi-purpose field robotics will reduce the resources required for experimental research considerably due to reuse of existing work across projects and robotic platforms. This thesis describes the FroboMind field robot software platform developed in this work and presents...

  4. Agricultural and management practices and bacterial contamination in greenhouse versus open field lettuce production.

    Science.gov (United States)

    Holvoet, Kevin; Sampers, Imca; Seynnaeve, Marleen; Jacxsens, Liesbeth; Uyttendaele, Mieke

    2014-12-23

    The aim of this study was to gain insight into potential differences in risk factors for microbial contamination in greenhouse versus open field lettuce production. Information was collected on sources, testing, and monitoring and if applicable, treatment of irrigation and harvest rinsing water. These data were combined with results of analysis on the levels of Escherichia coli as a fecal indicator organism and the presence of enteric bacterial pathogens on both lettuce crops and environmental samples. Enterohemorragic Escherichia coli (EHEC) PCR signals (vt1 or vt2 positive and eae positive), Campylobacter spp., and Salmonella spp. isolates were more often obtained from irrigation water sampled from open field farms (21/45, 46.7%) versus from greenhouse production (9/75, 12.0%). The open field production was shown to be more prone to fecal contamination as the number of lettuce samples and irrigation water with elevated E. coli was significantly higher. Farmers comply with generic guidelines on good agricultural practices available at the national level, but monitoring of microbial quality, and if applicable appropriateness of water treatment, or water used for irrigation or at harvest is restricted. These results indicate the need for further elaboration of specific guidelines and control measures for leafy greens with regard to microbial hazards.

  5. Green house gas emissions from open field burning of agricultural residues in India.

    Science.gov (United States)

    Murali, S; Shrivastava, Rajnish; Saxena, Mohini

    2010-10-01

    In India, about 435.98 MMT of agro-residues are produced every year, out of which 313.62 MMT are surplus. These residues are either partially utilized or un-utilised due to various constraints. To pave the way for subsequent season for agriculture activity, the excess crop residues are burnt openly in the fields, unmindful of their ill effects on the environment. The present study has been undertaken to evaluate the severity of air pollution through emission of green house gases (GHGs) due to open field burning of agro-residues in India. Open field burning of surplus agro-residues in India results in the emission of GHG. Emissions of CH4 and N2O in 1997-98 and 2006-07 have been 3.73 and 4.06 MMT CO2 equivalent, which is an increase of 8.88% over a decade. About three-fourths of GHG emissions from agro-residues burning were CH4 and the remaining one-fourth were N2O. Burning of wheat and paddy straws alone contributes to about 42% of GHGs. These GHG emissions can be avoided once the agro-residues are employed for sustainable, cost-effective and environment- friendly options like power generation.

  6. Ontogeny of sex differences in open-field ambulation in the rat.

    Science.gov (United States)

    Slob, A K; Huizer, T; Van der Werff ten Bosch, J J

    1986-01-01

    The effects of age and gonads were studied in rats subjected to open-field tests, during which ambulation behavior was recorded. Subjects were three groups of male and female rats: sham-operation on day 1 and day 21; gonadectomy on day 1 and sham-operation on day 21; and sham-operation on day 1 and gonadectomy on day 21. Half of each group were tested in a circular open field (3 min/day, 3 consecutive days) on days 28-30; the others were tested on days 47-49. Representatives of both batches were tested again in a square open field on days 76-78. There was a sex difference in ambulation at 77 days, but not at earlier ages. In animals gonadectomized on day 1 or day 21 the sex difference in adulthood failed to occur, because castration caused the males to ambulate as much as sham-operated and ovariectomized females. On the basis of our results and reports in the literature it is suggested that testicular secretions around puberty have an organizing effect on ambulation behavior. The intact adult male rat ambulates less than the adult female and this difference persists after castration in adulthood. Castration well before puberty prevents the development of the adult sex difference.

  7. Catastrophe of coronal magnetic flux ropes in fully open magnetic field

    Institute of Scientific and Technical Information of China (English)

    LI; Guoqiang(李国强); HU; Youqiu(胡友秋)

    2002-01-01

    The catastrophe of coronal magnetic flux ropes is closely related to solar explosive phenomena, such as prominence eruptions, coronal mass ejections, and two-ribbon solar flares. Using a 2-dimensional, 3-component ideal MHD model in Cartesian coordinates, numerical simulations are carried out to investigate the equilibrium property of a coronal magnetic flux rope which is embedded in a fully open background magnetic field. The flux rope emerges from the photosphere and enters the corona with its axial and annular magnetic fluxes controlled by a single "emergence parameter". For a flux rope that has entered the corona, we may change its axial and annular fluxes artificially and let the whole system reach a new equilibrium through numerical simulations. The results obtained show that when the emergence parameter, the axial flux, or the annular flux is smaller than a certain critical value, the flux rope is in equilibrium and adheres to the photosphere. On the other hand, if the critical value is exceeded, the flux rope loses equilibrium and erupts freely upward, namely, a catastrophe takes place. In contrast with the partly-opened background field, the catastrophic amplitude is infinite for the case of fully-opened background field.

  8. Agricultural and Management Practices and Bacterial Contamination in Greenhouse versus Open Field Lettuce Production

    Directory of Open Access Journals (Sweden)

    Kevin Holvoet

    2014-12-01

    Full Text Available The aim of this study was to gain insight into potential differences in risk factors for microbial contamination in greenhouse versus open field lettuce production. Information was collected on sources, testing, and monitoring and if applicable, treatment of irrigation and harvest rinsing water. These data were combined with results of analysis on the levels of Escherichia coli as a fecal indicator organism and the presence of enteric bacterial pathogens on both lettuce crops and environmental samples. Enterohemorragic Escherichia coli (EHEC PCR signals (vt1 or vt2 positive and eae positive, Campylobacter spp., and Salmonella spp. isolates were more often obtained from irrigation water sampled from open field farms (21/45, 46.7% versus from greenhouse production (9/75, 12.0%. The open field production was shown to be more prone to fecal contamination as the number of lettuce samples and irrigation water with elevated E. coli was significantly higher. Farmers comply with generic guidelines on good agricultural practices available at the national level, but monitoring of microbial quality, and if applicable appropriateness of water treatment, or water used for irrigation or at harvest is restricted. These results indicate the need for further elaboration of specific guidelines and control measures for leafy greens with regard to microbial hazards.

  9. Genetic and phenotypic correlations between feather pecking and open-field reponse in laying hens at two different ages

    NARCIS (Netherlands)

    Rodenburg, T.B.; Buitenhuis, A.J.; Ask, B.; Uitdehaag, K.A.; Koene, P.; Poel, van der J.J.; Arendonk, van J.A.M.; Bovenhuis, H.

    2004-01-01

    The object of this research was to study the relationship between feather pecking and open-field activity in laying hens at two different ages. A population of 550 birds of a laying hen cross was subjected to an open-field test at 5 and 29 weeks of age and to a social feather pecking test at 6 and 3

  10. Can field-scale habitat diversification enhance the biocontrol potential of spiders?

    Science.gov (United States)

    Samu, Ferenc

    2003-04-01

    The study investigated the effect of strip management in alfalfa on the abundance and diversity of spiders. In strip management, narrow strips were left unmown in the crop, which were then shifted at next mowing. In an experimental field, out of the six 50 x 50-m blocks, three received strip management and three were managed traditionally (ie the whole block was mown). Our main hypothesis was that unmown strips will contain a more diverse and abundant spider assemblage, which will increase spider numbers in the mown parts of the crop. Over the 3 years of the study, unmown strips contained a spider assemblage of more than 50% higher abundance than in control alfalfa. Species diversity was also greater in the strips, and the presence of specific indicator species could be shown. We found that five dominant species comprised over 75% of spiders in the strips, and they were the same species as those that are dominant in alfalfa, where they represent 85% of all spiders. In contrast, a neighbouring meadow, which was a control in the study, also had high diversity, but different dominant species. The main result of the experiment was negative in that elevated abundance of spiders in unmown strips did not raise spider numbers in the mown strips of alfalfa, where abundance was only marginally higher than in the control alfalfa. We can speculate that better ecological conditions in unmown strips attract and conserve spiders from neighbouring areas and from the crop at mowing. We suggest that if diversification is more interspersed within the crop, we have a higher chance of increasing the number of natural enemies and bringing them closer to pests, so that they can interact more intensively.

  11. Displacement and stress fields around rock fractures opened by irregular overpressure variations

    Directory of Open Access Journals (Sweden)

    Shigekazu eKusumoto

    2014-05-01

    Full Text Available Many rock fractures are entirely driven open by fluids such as ground water, geothermal water, gas, oil, and magma. These are a subset of extension fractures (mode I cracks; e.g., dikes, mineral veins and joints referred to as hydrofractures. Field measurements show that many hydrofractures have great variations in aperture. However, most analytical solutions for fracture displacement and stress fields assume the loading to be either constant or with a linear variation. While these solutions have been widely used, it is clear that a fracture hosted by heterogeneous and anisotropic rock is normally subject to loading that is neither constant nor with a linear variation. Here we present new general solutions for the displacement and stress fields around hydrofractures, modelled as two-dimensional elastic cracks, opened by irregular overpressure variations given by the Fourier cosine series. Each solution has two terms. The first term gives the displacement and stress fields due to the average overpressure acting inside the crack; it is given by the initial term of the Fourier coefficients expressing the overpressure variation. The second term gives the displacement and stress fields caused by the overpressure variation; it is given by general terms of the Fourier coefficients and solved through numerical integration. Our numerical examples show that the crack aperture variation closely reflects the overpressure variation. Also, that the general displacement and stress fields close to the crack follow the overpressure variation but tend to be more uniform far from the crack. The present solutions can be used to estimate the displacement and stress fields around any fluid-driven crack, that is, any hydrofracture, as well as its aperture, provided the variation in overpressure can be described by Fourier series. The solutions add to our understanding of local stresses, displacements, and fluid transport associated with hydrofractures in the crust.

  12. Acoustic modeling of a three-dimensional rectangular opened enclosure coupled with a semi-infinite exterior field at the baffled opening.

    Science.gov (United States)

    Jin, Guoyong; Shi, Shuangxia; Liu, Zhigang

    2016-11-01

    A modeling method is proposed for the acoustic analysis of a three-dimensional (3D) rectangular opened enclosure coupled with a semi-infinite exterior field by a rectangular opening of arbitrary size, and with general wall impedance. In contrast to existing modeling methods that solve the differential equations, the energy principle in combination with a 3D modified Fourier cosine series is employed in the present method for the modeling of this system. Under this theoretical framework, the effect of an opening in the wall of a rectangular enclosure is taken into account via the work done by the sound pressure acting on the opening between the finite enclosure and exterior domain. The sound pressure inside the opened enclosure is expressed as the combination of a 3D trigonometric cosine series and one supplementary 2D expansion introduced to ensure uniform convergence of the solution over the entire solution domain including opening boundary. The acoustic responses of the opened enclosure are obtained based on the energy expressions for the enclosure system. The effectiveness and reliability of the current method are checked against the results obtained by the boundary element method and experimental results, and excellent agreement is achieved. The effects of sizes and positions of the opening and wall impedance on the acoustic behaviors of opened enclosure system are investigated.

  13. Characteristics of geometric distortion correction with increasing field-of-view in open-configuration MRI.

    Science.gov (United States)

    Hong, Cheolpyo; Lee, Dong-Hoon; Han, Bong Soo

    2014-07-01

    Open-configuration magnetic resonance imaging (MRI) systems are becoming increasingly desirable for musculoskeletal imaging and image-guided radiotherapy because of their non-claustrophobic configuration. However, geometric image distortion in large fields-of-view (FOV) due to field inhomogeneity and gradient nonlinearity hinders the practical applications of open-type MRI. We demonstrated the use of geometric distortion correction for increasing FOV in open MRI. Geometric distortion was modeled and corrected as a global polynomial function. The appropriate polynomial order was identified as the minimum difference between the coordinates of control points in the distorted MR image space and those predicted by polynomial modeling. The sixth order polynomial function was found to give the optimal value for geometric distortion correction. The area of maximum distortion was<1 pixel with an FOV of 285mm. The correction performance error was increased at most 1.2% and 2.9% for FOVs of 340mm and~400mm compared with the FOV of 285mm. In particular, unresolved distortion was generated by local deformation near the gradient coil center. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Comparison between visual field defect in pigmentary glaucoma and primary open-angle glaucoma.

    Science.gov (United States)

    Nilforushan, Naveed; Yadgari, Maryam; Jazayeri, Anisalsadat

    2016-10-01

    To compare visual field defect patterns between pigmentary glaucoma and primary open-angle glaucoma. Retrospective, comparative study. Patients with diagnosis of primary open-angle glaucoma (POAG) and pigmentary glaucoma (PG) in mild to moderate stages were enrolled in this study. Each of the 52 point locations in total and pattern deviation plot (excluding 2 points adjacent to blind spot) of 24-2 Humphrey visual field as well as six predetermined sectors were compared using SPSS software version 20. Comparisons between 2 groups were performed with the Student t test for continuous variables and the Chi-square test for categorical variables. Thirty-eight eyes of 24 patients with a mean age of 66.26 ± 11 years (range 48-81 years) in the POAG group and 36 eyes of 22 patients with a mean age of 50.52 ± 11 years (range 36-69 years) in the PG group were studied. (P = 0.00). More deviation was detected in points 1, 3, 4, and 32 in total deviation (P = 0.03, P = 0.015, P = 0.018, P = 0.023) and in points 3, 4, and 32 in pattern deviation (P = 0.015, P = 0.049, P = 0.030) in the POAG group, which are the temporal parts of the field. It seems that the temporal area of the visual field in primary open-angle glaucoma is more susceptible to damage in comparison with pigmentary glaucoma.

  15. Field-oriented control of five-phase induction motor with open-end stator winding

    Directory of Open Access Journals (Sweden)

    Listwan Jacek

    2016-09-01

    Full Text Available The mathematical model of the five-phase squirrel-cage induction motor and the system of the dual five-phase voltage source inverter have been presented. The control methods and control systems of the field-oriented control of the five-phase induction motor with an open-end stator winding are described. The structures of the direct fieldoriented control system (DFOC and the Indirect Field-oriented control system (IFOC with PI controllers in outer and inner control loops are analyzed. A method of space vector modulation used to control the system of the dual five-phase voltage source inverter has been discussed. The results of simulation studies of the field-oriented control methods are presented. Comparative analysis of the simulation results was carried out.

  16. Open-Loop Control in Quantum Optics: Two-Level Atom in Modulated Optical Field

    CERN Document Server

    Saifullah, Sergei

    2008-01-01

    The methods of mathematical control theory are widely used in the modern physics, but still they are less popular in quantum science. We will discuss the aspects of control theory, which are the most useful in applications to the real problems of quantum optics. We apply this technique to control the behavior of the two-level quantum particles (atoms) in the modulated external optical field in the frame of the so called "semi classical model", where quantum two-level atomic system (all other levels are neglected) interacts with classical electromagnetic field. In this paper we propose a simple model of feedforward (open-loop) control for the quantum particle system, which is a basement for further investigation of two-level quantum particle in the external one-dimensional optical field.

  17. Automated tracing of open-field coronal structures for an optimized large-scale magnetic field reconstruction

    Science.gov (United States)

    Uritsky, V. M.; Davila, J. M.; Jones, S. I.

    2014-12-01

    Solar Probe Plus and Solar Orbiter will provide detailed measurements in the inner heliosphere magnetically connected with the topologically complex and eruptive solar corona. Interpretation of these measurements will require accurate reconstruction of the large-scale coronal magnetic field. In a related presentation by S. Jones et al., we argue that such reconstruction can be performed using photospheric extrapolation methods constrained by white-light coronagraph images. Here, we present the image-processing component of this project dealing with an automated segmentation of fan-like coronal loop structures. In contrast to the existing segmentation codes designed for detecting small-scale closed loops in the vicinity of active regions, we focus on the large-scale geometry of the open-field coronal features observed at significant radial distances from the solar surface. The coronagraph images used for the loop segmentation are transformed into a polar coordinate system and undergo radial detrending and initial noise reduction. The preprocessed images are subject to an adaptive second order differentiation combining radial and azimuthal directions. An adjustable thresholding technique is applied to identify candidate coronagraph features associated with the large-scale coronal field. A blob detection algorithm is used to extract valid features and discard noisy data pixels. The obtained features are interpolated using higher-order polynomials which are used to derive empirical directional constraints for magnetic field extrapolation procedures based on photospheric magnetograms.

  18. The effects of island forest restoration on open habitat specialists: the endangered weevil Hadramphus spinipennis Broun and its host-plant Aciphylla dieffenbachii Kirk

    Directory of Open Access Journals (Sweden)

    Emily D. Fountain

    2015-02-01

    Full Text Available Human alteration of islands has made restoration a key part of conservation management. As islands are restored to their original state, species interactions change and some populations may be impacted. In this study we examine the coxella weevil, (Hadramphus spinipennis Broun and its host-plant Dieffenbach’s speargrass (Aciphylla dieffenbachii Kirk, which are both open habitat specialists with populations on Mangere and Rangatira Islands, Chathams, New Zealand. Both of these islands were heavily impacted by the introduction of livestock; the majority of the forest was removed and the weevil populations declined due to the palatability of their host-plant to livestock. An intensive reforestation program was established on both islands over 50 years ago but the potential impacts of this restoration project on the already endangered H. spinipennis are poorly understood. We combined genetic and population data from 1995 and 2010–2011 to determine the health and status of these species on both islands. There was some genetic variation between the weevil populations on each island but little variation within the species as a whole. The interactions between the weevil and its host-plant populations appear to remain intact on Mangere, despite forest regeneration. A decline in weevils and host-plant on Rangatira does not appear to be caused by canopy regrowth. We recommend that (1 these populations be monitored for ongoing effects of long-term reforestation, (2 the cause of the decline on Rangatira be investigated, and (3 the two populations of weevils be conserved as separate evolutionarily significant units.

  19. Quasimodal expansion of electromagnetic fields in open two-dimensionnal structures

    CERN Document Server

    Vial, Benjamin; Nicolet, André; Commandré, Mireille

    2013-01-01

    A quasimodal expansion method (QMEM) is developed to model and understand the scattering properties of arbitrary shaped two-dimensional (2-D) open structures. In contrast with the bounded case which have only discrete spectrum (real in the lossless media case), open resonators show a continuous spectrum composed of radiation modes and may also be characterized by resonances associated to complex eigenvalues (quasimodes). The use of a complex change of coordinates to build Perfectly Matched Layers (PMLs) allows the numerical computation of those quasimodes and of approximate radiation modes. Unfortunately, the transformed operator at stake is no longer self-adjoint, and classical modal expansion fails. To cope with this issue, we consider an adjoint eigenvalue problem which eigenvectors are bi-orthogonal to the eigenvectors of the initial problem. The scattered field is expanded on this complete set of modes leading to a reduced order model of the initial problem. The different contributions of the eigenmodes ...

  20. Open-Access, Low-Magnetic-Field MRI System for Lung Research

    Science.gov (United States)

    Mair, Ross W.; Rosen, Matthew S.; Tsai, Leo L.; Walsworth, Ronald L.; Hrovat, Mirko I.; Patz, Samuel; Ruset, Iullian C.; Hersman, F. William

    2009-01-01

    An open-access magnetic resonance imaging (MRI) system is being developed for use in research on orientational/gravitational effects on lung physiology and function. The open-access geometry enables study of human subjects in diverse orientations. This system operates at a magnetic flux density, considerably smaller than the flux densities of typical other MRI systems, that can be generated by resistive electromagnet coils (instead of the more-expensive superconducting coils of the other systems). The human subject inhales air containing He-3 or Xe-129 atoms, the nuclear spins of which have been polarized by use of a laser beam to obtain a magnetic resonance that enables high-resolution gas space imaging at the low applied magnetic field. The system includes a bi-planar, constant-current, four-coil electromagnet assembly and associated electronic circuitry to apply a static magnetic field of 6.5 mT throughout the lung volume; planar coils and associated circuitry to apply a pulsed magnetic-field-gradient for each spatial dimension; a single, detachable radio-frequency coil and associated circuitry for inducing and detecting MRI signals; a table for supporting a horizontal subject; and electromagnetic shielding surrounding the electromagnet coils.

  1. Combining field observations and numerical modeling to better understand fault opening and hydromechanics at depth

    Science.gov (United States)

    Ritz, E.; Pollard, D. D.

    2012-12-01

    This study adds field observations and numerical modeling results to the mounting evidence that fault surface irregularities cause local variations in slip, opening, and stress distributions along faults. A two-dimensional displacement discontinuity boundary element model (DDM) in conjunction with a complementarity algorithm is used to model both idealized and natural fault geometries in order to predict the locations and magnitudes of fault opening, and the style and spatial distribution of off-fault damage, both of which influence local fluid flow. Field observations of exhumed small faults in granodiorite from the central Sierra Nevada, California, help to constrain the numerical models. The Sierran faults exhibit sections of opening that became conduits for fluid flow and void spaces for precipitation of hydrothermal minerals; these sections are often surrounded by fractured and altered wall rock, presumably due to local stress concentrations and the influx of chemically reactive fluids. We are further developing the DDM with complementarity to add internal fluid pressure or normal cohesion along the fault surfaces, which are assigned independently of other contact properties, such as the frictional strength and coefficient of friction. While variable frictional strength or internal normal stress along a planar fault may produce opening or perturb the local stress state, these boundary conditions do not accurately mimic the mechanical behavior of faults with non-planar geometries. We advocate using the nomenclature 'lee' and 'stoss' to describe curved faults rather than 'releasing' and 'restraining bends', because the implied mechanical conditions are not necessarily met. Numerical experiments for idealized curved model faults demonstrate that fault opening can occur along lee sides of the curves, with the enhancing effects of fluid pressure and despite the countervailing effects of increased confining pressure with depth. Ambient effective compressive stresses

  2. Post-training scopolamine treatment induced maladaptive behavior in open field habituation task in rats.

    Directory of Open Access Journals (Sweden)

    Natalija Popović

    Full Text Available The effects of scopolamine on memory consolidation are controversial and depend on several factors (i.e. site of administration, time of administration and testing, dose, cognitive task, experimental protocol, specie, strain, etc.. Generally, the range dose of systemic administered scopolamine, used in memory consolidation studies, has varied from 0.05 to 50 mg/kg. However, according to the literature, the most frequently used doses of scopolamine efficient on memory consolidation, are 1 and 30 mg/kg, low and high doses, respectively. In open field habituation studies only lower doses of scopolamine were used to test memory consolidation. Therefore, in the present study we compared the effects of low (1 mg/kg and high (30 mg/kg scopolamine dose, on the open field habituation task, in male Wistar rats. Scopolamine was administered immediately after the acquisition task and animals were retested 48 h later on. On the retested day, the ambulation and rearing in the open field decreased in the same manner in all tested groups. In saline- and 1 mg/kg scopolamine-treated animals, the time spent in grooming significantly decreased in the habituation task, while the same parameter significantly increased in animals treated with 30 mg/kg of scopolamine. The defecation rate significantly decreased (control group, maintained (1 mg/kg of scopolamine treated animals or significantly increased (30 mg/kg of scopolamine treated group on retention test. In conclusion, the present data suggest that post-training scopolamine administration does not affect locomotion neither exploration in the habituation to a novel environment, but increases defecation and grooming, two behaviours associated with fearful and stressful situations.

  3. Open field trial of genetically modified parthenocarpic tomato: seedlessness and fruit quality

    Directory of Open Access Journals (Sweden)

    Pandolfini Tiziana

    2005-12-01

    Full Text Available Abstract Background Parthenocarpic tomato lines transgenic for the DefH9-RI-iaaM gene have been cultivated under open field conditions to address some aspects of the equivalence of genetically modified (GM fruit in comparison to controls (non-GM. Results Under open field cultivation conditions, two tomato lines (UC 82 transgenic for the DefH9-RI-iaaM gene produced parthenocarpic fruits. DefH9-RI-iaaM fruits were either seedless or contained very few seeds. GM fruit quality, with the exception of a higher β-carotene level, did not show any difference, neither technological (colour, firmness, dry matter, °Brix, pH nor chemical (titratable acidity, organic acids, lycopene, tomatine, total polyphenols and antioxidant capacity – TEAC, when compared to that of fruits from control line. Highly significant differences in quality traits exist between the tomato F1 commercial hybrid Allflesh and the three UC 82 genotypes tested, regardless of whether or not they are GM. Total yield per plant did not differ between GM and parental line UC 82. Fruit number was increased in GM lines, and GM fruit weight was decreased. Conclusion The use in the diet of fruits from a new line or variety introduces much greater changes than the consumption of GM fruits in comparison to its genetic background. Parthenocarpic fruits, produced under open field conditions, contained 10-fold less seeds than control fruits. Thus parthenocarpy caused by DefH9-RI-iaaM gene represents also a tool for mitigating GM seeds dispersal in the environment.

  4. Open questions on the origin of life at anoxic geothermal fields.

    Science.gov (United States)

    Mulkidjanian, Armen Y; Bychkov, Andrew Yu; Dibrova, Daria V; Galperin, Michael Y; Koonin, Eugene V

    2012-10-01

    We have recently reconstructed the 'hatcheries' of the first cells by combining geochemical analysis with phylogenomic scrutiny of the inorganic ion requirements of universal components of modern cells (Mulkidjanian et al. Proc Natl Acad Sci U S A 109:E821-830, 2012). These ubiquitous, and by inference primordial, proteins and functional systems show affinity to and functional requirement for K⁺, Zn²⁺, Mn²⁺, and phosphate. Thus, protocells must have evolved in habitats with a high K⁺/Na⁺ ratio and relatively high concentrations of Zn, Mn and phosphorous compounds. Geochemical reconstruction shows that the ionic composition conducive to the origin of cells could not have existed in marine settings but is compatible with emissions of vapor-dominated zones of inland geothermal systems. Under an anoxic, CO₂-dominated atmosphere, the ionic composition of pools of cool, condensed vapor at anoxic geothermal fields would resemble the internal milieu of modern cells. Such pools would be lined with porous silicate minerals mixed with metal sulfides and enriched in K⁺ ions and phosphorous compounds. Here we address some questions that have appeared in print after the publication of our anoxic geothermal field scenario. We argue that anoxic geothermal fields, which were identified as likely cradles of life by using a top-down approach and phylogenomics analysis, could provide geochemical conditions similar to those which were suggested as most conducive for the emergence of life by the chemists who pursuit the complementary bottom-up strategy.

  5. Ground beetles (Coleoptera: Carabidae of rice field banks and restored habitats in an agricultural area of the Po Plain (Lombardy, Italy

    Directory of Open Access Journals (Sweden)

    Nicola Pilon

    2013-11-01

    Full Text Available An entomological investigation was carried out in an agricultural area, mainly rice fields, of the Po river plain, located in the municipalities of Lacchiarella (MI and Giussago (PV (Lombardy, Italy. In 2009 and 2010, ground beetles (Coleoptera: Carabidae were sampled along rice field banks and in restored habitats, by means of pitfall traps. The area appeared as species-rich, compared to other anthropogenic habitats in the Po river pain. Most of the collected Carabids were species with a wide distribution in the Paleartic region, eurytopic and common in European agroecosystems. The assemblages were dominated by small-medium, macropterous species, with summer larvae. No endemic species were found. Species with southern distribution, rarely found north of the Po river, were also sampled. Amara littorea is recorded for the first time in Italy.

  6. Coherent field emission from a multi-walled carbon nanotube with two open-ended branches

    Institute of Scientific and Technical Information of China (English)

    Bai Xin; Zhang Geng-Min; Wang Ming-Sheng; Zhang Zhao-Xiang; Yu Jie; Zhao Xing-Yu; Guo Deng-Zhu; Xue Zeng-Quan

    2009-01-01

    Interference fringes are obtained in a field-emission microscopy (FEM) study of a multi-walled carbon nanotube (MWCNT) with two open-ended branches.The FEM pattern,which is composed of three parallel streaks,can be interpreted by using classical Young's double-slit interference with the ends of the two MWCNT branches treated as two secondary sources of the electron wave.The origin of the coherency of the electron beams from the two branches is discussed on the basis of the quantitative analysis of the FEM pattern.The result suggests a new approach to obtaining a coherent electron source.

  7. Pathological behavior of the open-shell restricted self-consistent-field equations

    Energy Technology Data Exchange (ETDEWEB)

    Moscardo, F.; Alvarez-Collado, J.R.

    1979-02-01

    The possible solutions of open-shell restricted self-consistent-field equations for a doublet are studied for Li and Na atoms, according to the values of the parameters implied in those equations. A similar behavior, characterized by the presence of several variational solutions is observed in both atoms. Some of these solutions can be assigned to excited configurations. Excitation energies are in good agreement with experimental data. Doublet stability for the solutions obtained has been studied, discussing the saddle-point character present in those solutions associated to excited configurations.

  8. [Association between the canine monoamine oxidase B (MAOB) gene polymorphisms and behavior of puppies in open-field test].

    Science.gov (United States)

    Li, Xiao-Hui; Xu, Han-Kun; Mao, Da-Gan; Ma, Da-Jun; Chen, Peng; Yang, Li-Guo

    2006-11-01

    Excitability, activity and exploration behavior of puppies in a novel open-field were tested in a total of 204 two-month-old German shepherd dog, labrador retriever or English springer spaniel puppies. The polymorphisms of monoamine oxidase B gene (MAOB) were detected by PCR-RFLP. Statistics analysis indicated that genotype and allele frequencies of the polymorphisms were significantly different among three breeds (P open-field test. The results showed that MAOB gene polymorphisms had a significant effect on walking time, squares crossed, lying time, the times of standing up against walls(P open-field test and TT genotype has favorable effects in these behavior traits.

  9. Reconstructing the open-field magnetic geometry of solar corona using coronagraph images

    Science.gov (United States)

    Uritsky, Vadim M.; Davila, Joseph M.; Jones, Shaela; Burkepile, Joan

    2015-04-01

    The upcoming Solar Probe Plus and Solar Orbiter missions will provide an new insight into the inner heliosphere magnetically connected with the topologically complex and eruptive solar corona. Physical interpretation of these observations will be dependent on the accurate reconstruction of the large-scale coronal magnetic field. We argue that such reconstruction can be performed using photospheric extrapolation codes constrained by white-light coronagraph images. The field extrapolation component of this project is featured in a related presentation by S. Jones et al. Here, we focus on our image-processing algorithms conducting an automated segmentation of coronal loop structures. In contrast to the previously proposed segmentation codes designed for detecting small-scale closed loops in the vicinity of active regions, our technique focuses on the large-scale geometry of the open-field coronal features observed at significant radial distances from the solar surface. Coronagraph images are transformed into a polar coordinate system and undergo radial detrending and initial noise reduction followed by an adaptive angular differentiation. An adjustable threshold is applied to identify candidate coronagraph features associated with the large-scale coronal field. A blob detection algorithm is used to identify valid features against a noisy background. The extracted coronal features are used to derive empirical directional constraints for magnetic field extrapolation procedures based on photospheric magnetograms. Two versions of the method optimized for processing ground-based (Mauna Loa Solar Observatory) and satellite-based (STEREO Cor1 and Cor2) coronagraph images are being developed.

  10. Economies: An Open Access Journal for the Field of Development Macroeconomics

    Directory of Open Access Journals (Sweden)

    Ralf Fendel

    2013-01-01

    Full Text Available Economies (ISSN 2227-7099 is a new international, peer-reviewed open access journal for the academic fields of development economics and macroeconomics. While the latter seems to be clearly defined, development economics is not, because it is related to nearly all traditional economic sub-disciplines such as macroeconomics, international trade and finance, as well as microeconomics and public finance. Typically, academic field journals of development economics cover all those economic sub-disciplines. Economies instead focuses mainly on the macroeconomic perspective of economic development and it intends to publish academic research that is of strong macroeconomic policy relevance. In general, contributions in Economies should foster understanding of the macroeconomic process of economic development, with the process of development not exclusively being reserved to what we typically call developing countries. Also, the group of developed economies is still developing in the sense of improving their living standards further.

  11. Towards an Open Software Platform for Field Robots in Precision Agriculture

    DEFF Research Database (Denmark)

    Jensen, Kjeld; Larsen, Morten; Nielsen, Søren H

    2014-01-01

    software complexity. A lack of collaboration between research groups contributes to the problem. Scientific publications describe methods and results from the work, but little field robot software is released and documented for others to use. We hypothesize that a common open software platform tailored......Robotics in precision agriculture has the potential to improve competitiveness and increase sustainability compared to current crop production methods and has become an increasingly active area of research. Tractor guidance systems for supervised navigation and implement control have reached...... the market, and prototypes of field robots performing precision agriculture tasks without human intervention also exist. But research in advanced cognitive perception and behaviour that is required to enable a more efficient, reliable and safe autonomy becomes increasingly demanding due to the growing...

  12. Image-guided spinal injection procedures in open high-field MRI with vertical field orientation: feasibility and technical features

    Energy Technology Data Exchange (ETDEWEB)

    Streitparth, F.; Walter, T.; Wonneberger, U.; Wagner, M.; Hermann, K.G.; Hamm, B.; Teichgraeber, U. [Charite, Humboldt-Universitaet zu Berlin, Department of Radiology, Berlin (Germany); Chopra, S. [Charite-Universitaetsmedizin Berlin, Campus Virchow Klinikum, Department of General, Visceral, and Transplantation Surgery, Berlin (Germany); Wichlas, F. [Charite-Universitaetsmedizin Berlin, Campus Virchow Klinikum, Center for Musculoskeletal Surgery, Berlin (Germany)

    2010-02-15

    We prospectively evaluated the feasibility and technical features of MR-guided lumbosacral injection procedures in open high-field MRI at 1.0 T. In a CuSO{sub 4}.5H{sub 2}O phantom and five human cadaveric spines, fluoroscopy sequences (proton-density-weighted turbo spin-echo (PDw TSE), T1w TSE, T2w TSE; balanced steady-state free precession (bSSFP), T1w gradient echo (GE), T2w GE) were evaluated using two MRI-compatible 20-G Chiba-type needles. Artefacts were analysed by varying needle orientation to B{sub 0}, frequency-encoding direction and slice orientation. Image quality was described using the contrast-to-noise ratio (CNR). Subsequently, a total of 183 MR-guided nerve root (107), facet (53) and sacroiliac joint (23) injections were performed in 53 patients. In vitro, PDw TSE sequence yielded the best needle-tissue contrasts (CNR = 45, 18, 15, 9, and 8 for needle vs. fat, muscle, root, bone and sclerosis, respectively) and optimal artefact sizes (width and tip shift less than 5 mm). In vivo, PDw TSE sequence was sufficient in all cases. The acquisition time of 2 s facilitated near-real-time MRI guidance. Drug delivery was technically successful in 100% (107/107), 87% (46/53) and 87% (20/23) of nerve root, facet and sacroiliac joint injections, respectively. No major complications occurred. The mean procedure time was 29 min (range 19-67 min). MR-guided spinal injections in open high-field MRI are feasible and accurate using fast TSE sequence designs. (orig.)

  13. Open release of male mosquitoes infected with a wolbachia biopesticide: field performance and infection containment.

    Directory of Open Access Journals (Sweden)

    Linda O'Connor

    Full Text Available BACKGROUND: Lymphatic filariasis (LF is a globally significant disease, with 1.3 billion persons in 83 countries at risk. A coordinated effort of administering annual macrofilaricidal prophylactics to the entire at-risk population has succeeded in impacting and eliminating LF transmission in multiple regions. However, some areas in the South Pacific are predicted to persist as transmission sites, due in part to the biology of the mosquito vector, which has led to a call for additional tools to augment drug treatments. Autocidal strategies against mosquitoes are resurging in the effort against invasive mosquitoes and vector borne disease, with examples that include field trials of genetically modified mosquitoes and Wolbachia population replacement. However, critical questions must be addressed in anticipation of full field trials, including assessments of field competitiveness of transfected males and the risk of unintended population replacement. METHODOLOGY/PRINCIPAL FINDINGS: We report the outcome of field experiments testing a strategy that employs Wolbachia as a biopesticide. The strategy is based upon Wolbachia-induced conditional sterility, known as cytoplasmic incompatibility, and the repeated release of incompatible males to suppress a population. A criticism of the Wolbachia biopesticide approach is that unintended female release or horizontal Wolbachia transmission can result in population replacement instead of suppression. We present the outcome of laboratory and field experiments assessing the competitiveness of transfected males and their ability to transmit Wolbachia via horizontal transmission. CONCLUSIONS/SIGNIFICANCE: The results demonstrate that Wolbachia-transfected Aedes polynesiensis males are competitive under field conditions during a thirty-week open release period, as indicated by mark, release, recapture and brood-hatch failure among females at the release site. Experiments demonstrate the males to be 'dead end hosts

  14. Cumulative and Synergistic Effects of Physical, Biological, and Acoustic Signals on Marine Mammal Habitat Use Physical Oceanography Component: Soundscapes Under Sea Ice: Can We Listen for Open Water?

    Science.gov (United States)

    2013-09-30

    disappear as these mammals begin their annual migration to the Arctic Ocean. The soundscape shows loud floe-banging conditions mixed with periods of...Physical, Biological, and Acoustic Signals on Marine Mammal Habitat Use Physical Oceanography Component: Soundscapes Under Sea Ice: Can we listen for...research effort is to enhance the understanding of how variability in physical, biological, and acoustic signals impact marine mammal habitat use. This is

  15. Explosive events in connection with small scale flux emergence in open field regions

    Science.gov (United States)

    Galsgaard, Klaus; Moreno-Insertis, Fernando, , Prof

    In recent years observations have shown that the emergence of new magnetic flux from the convection zone into the open field regions in the corona may generate spectacular jet phenomena. A smaller number of jets seem to end their near steady state phase in one or more spectacular eruptions where material is accelerated away from the solar surface reaching fairly high velocities. To investigate the jet phenomena, we have conducted a number of numerical MHD experiments that investigate the general interaction between an emerging bipolar flux region and the open coronal magnetic field. Under the correct conditions, this generates a well defined jet phase and the model explains many of the general characteristics of the typical Eiffel tower jets. Towards the end phase of the jet, the remains of the emerged flux system may experience some violent eruptions. This talk will discuss the general characteristics of these eruptions, aiming at providing an explanation to why they occur, and how they develop in general. These jets and eruptions may be what is taking place in some of the so-called breakout models described in a number of recent observational papers.

  16. Solutions from boundary condition changing operators in open string field theory

    CERN Document Server

    Kiermaier, Michael; Soler, Pablo

    2010-01-01

    We construct analytic solutions of open string field theory using boundary condition changing (bcc) operators. We focus on bcc operators with vanishing conformal weight such as those for regular marginal deformations of the background. For any Fock space state phi, the component string field of the solution Psi exhibits a remarkable factorization property: it is given by the matter three-point function of phi with a pair of bcc operators, multiplied by a universal function that only depends on the conformal weight of phi. This universal function is given by a simple integral expression that can be computed once and for all. The three-point functions with bcc operators are thus the only needed physical input of the particular open string background described by the solution. We illustrate our solution with the example of the rolling tachyon profile, for which we prove convergence analytically. The form of our solution, which involves bcc operators instead of explicit insertions of the marginal operator, can b...

  17. Deep, Wide-field CCD Photometry for the Open Cluster NGC3532

    CERN Document Server

    Clem, James L; Hoard, D W; Wachter, Stefanie

    2011-01-01

    We present the results of a deep, wide-field CCD survey for the open cluster NGC~3532. Our new $BV(RI)_{c}$ photometry effectively covers a one square degree area and reaches an unprecedented depth of $V\\sim21$ to reveal that NGC~3532 is a rich open cluster that harbors a large number of faint, low-mass stars. We employ a number of methods to reduce the impact of field star contamination in the cluster color-magnitude diagrams, including supplementing our photometry with $JHK_{s}$ data from the 2MASS catalog. These efforts allow us to define a robust sample of candidate main sequence stars suitable for a purely empirical determination of the cluster's parameters by comparing them to the well-established Hyades main sequence. Our results confirm previous findings that NGC~3532 lies fairly near to the Sun [$(m-M)_0=8.46\\pm0.05$; $492^{+12}_{-11}$~pc] and has an extremely low reddening for its location near the Galactic plane [$E(B-V)=0.028\\pm0.006$]. Moreover, an age of $\\sim300$\\,Myr has been derived for the c...

  18. Place and Response Learning in the Open-field Tower Maze.

    Science.gov (United States)

    Lipatova, Olga; Campolattaro, Matthew M; Toufexis, Donna J; Mabry, Erin A

    2015-10-28

    This protocol describes how the Open-field Tower Maze (OFTM) paradigm is used to study spatial learning in rodents. This maze is especially useful for examining how rats learn to use a place- or response-learning to successfully navigate in an open-field arena. Additionally, this protocol describes how the OFTM differs from other behavioral maze paradigms that are commonly used to study spatial learning in rodents. The OFTM described in this article was adapted from the one previously described by Cole, Clipperton, and Walt (2007). Specifically, the OFTM was created to test spatial learning in rodents without the experimenter having to consider how "stress" might play a role as a confounding variable. Experiments have shown that stress-alone can significantly affect cognitive function(1). The representative results section contains data from an experiment that used the OFTM to examine the effects of estradiol treatment on place- and response-learning in adult female Sprague Dawley rats(2). Future studies will be designed to examine the role of the hippocampus and striatum in place- and response-learning in the OFTM.

  19. Function of the centromedial amygdala in reward devaluation and open-field activity.

    Science.gov (United States)

    Kawasaki, K; Glueck, A C; Annicchiarico, I; Papini, M R

    2015-09-10

    The present research aimed at determining the role played by the amygdala in reward devaluation using transient inactivation induced by lidocaine microinfusions into the centromedial region. Two situations involving reward devaluation were tested in rats: consummatory successive negative contrast (cSNC) and anticipatory negative contrast (ANC). In cSNC, rats exposed to a downshift from 32% to 4% sucrose consume less 4% sucrose than rats always exposed to 4% sucrose. Extensive evidence suggests that reward devaluation in the cSNC situation is accompanied by negative emotion. In ANC, rats consume less 4% sucrose when each session is closely followed by access to 32% sucrose rather than by 4% sucrose. Evidence suggests that reward devaluation in the ANC situation does not involve negative emotions; rather, ANC appears to involve Pavlovian anticipation of the higher value solution. To test the effects of lidocaine microinfusions in a situation known to induce negative emotion, but unrelated to reward devaluation, animals were also exposed to a lighted open field. Centromedial amygdala inactivation reduced the cSNC effect and increased exploratory behavior in the open field, both effects consistent with a reduction in negative emotional state. However, no detectable effects of amygdala inactivation were observed in the ANC situation. These results suggest that, first, the function of the amygdala is not unique to reward devaluation and, second, it is concerned with tagging the devaluation experience with aversive valence.

  20. [Performance of an open low-field MR unit in routine examination of knee lesions and comparison with high field systems].

    Science.gov (United States)

    Vahlensieck, M; Schnieber, O

    2003-02-01

    The purpose of this study was to analyze the diagnostic value of a low-field open MR system in the diagnosis of knee lesions and to compare it with that of high-field MR systems. In 139 knees,arthroscopic investigations were used as the gold standard to calculate sensitivity, specificity, predictive values and accuracy of the low-field open MR system. Figures for high field systems were taken from the literature. The values for the open MR system relative to arthroscopy were as follows: sensitivity 66%,specificity 95%,positive predictive value 64%,negative predictive value 92%, and accuracy 82%. The corresponding values taken from 10 relevant publications for highfield systems were: sensitivity 81%, specificity 90%, accuracy 90%. A lower diagnostic performance has to be expected using open low field MR units for knee lesions in comparison to high field units. Sedative drugs can make it possible for claustrophobic patients to be investigated in high-field units. The use of open low-field scanners may still be indicated in very adipose patients who do not fit into closed units.

  1. A field test of the relationship between habitat area and population size for five perennial plant species

    Directory of Open Access Journals (Sweden)

    H. H. Bruun

    2005-03-01

    Full Text Available The population sizes of five perennial vascular plant species confined to old unimproved dry grasslands were assessed, viz. Anthericum ramosum, Filipendula vulgaris, Silene nutans, Thymus pulegioides, and Thymus serpyllum. All populations within the region were included. Only for Filipendula vulgaris and Thymus serpyllum, significant relationships between habitat area and population size were found. Thus, apparently perennial vascular plants have a limited ability to respond to large habitat areas by forming large populations. This puts a question mark on the use of incidence-function models for the study of plant metapopulations, because these models are based on an assumed positive relationship between habitat area and population size.

  2. Cost Effective Open Geometry HTS MRI System amended to BSCCO 2212 Wire for High Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Kennth Marken

    2006-08-11

    The original goal of this Phase II Superconductivity Partnership Initiative project was to build and operate a prototype Magnetic Resonance Imaging (MRI) system using high temperature superconductor (HTS) coils wound from continuously processed dip-coated BSCCO 2212 tape conductor. Using dip-coated tape, the plan was for MRI magnet coils to be wound to fit an established commercial open geometry, 0.2 Tesla permanent magnet system. New electronics and imaging software for a prototype higher field superconducting system would have added significantly to the cost. However, the use of the 0.2 T platform would allow the technical feasibility and the cost issues for HTS systems to be fully established. Also it would establish the energy efficiency and savings of HTS open MRI compared with resistive and permanent magnet systems. The commercial goal was an open geometry HTS MRI running at 0.5 T and 20 K. This low field open magnet was using resistive normal metal conductor and its heat loss was rather high around 15 kolwatts. It was expected that an HTS magnet would dissipate around 1 watt, significantly reduce power consumption. The SPI team assembled to achieve this goal was led by Oxford Instruments, Superconducting Technology (OST), who developed the method of producing commercial dip coated tape. Superconductive Components Inc. (SCI), a leading US supplier of HTS powders, supported the conductor optimization through powder optimization, scaling, and cost reduction. Oxford Magnet Technology (OMT), a joint venture between Oxford Instruments and Siemens and the world’s leading supplier of MRI magnet systems, was involved to design and build the HTS MRI magnet and cryogenics. Siemens Magnetic Resonance Division, a leading developer and supplier of complete MRI imaging systems, was expected to integrate the final system and perform imaging trials. The original MRI demonstration project was ended in July 2004 by mutual consent of Oxford Instruments and Siemens. Between

  3. Cost Effective Open Geometry HTS MRI System amended to BSCCO 2212 Wire for High Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Kennth Marken

    2006-08-11

    The original goal of this Phase II Superconductivity Partnership Initiative project was to build and operate a prototype Magnetic Resonance Imaging (MRI) system using high temperature superconductor (HTS) coils wound from continuously processed dip-coated BSCCO 2212 tape conductor. Using dip-coated tape, the plan was for MRI magnet coils to be wound to fit an established commercial open geometry, 0.2 Tesla permanent magnet system. New electronics and imaging software for a prototype higher field superconducting system would have added significantly to the cost. However, the use of the 0.2 T platform would allow the technical feasibility and the cost issues for HTS systems to be fully established. Also it would establish the energy efficiency and savings of HTS open MRI compared with resistive and permanent magnet systems. The commercial goal was an open geometry HTS MRI running at 0.5 T and 20 K. This low field open magnet was using resistive normal metal conductor and its heat loss was rather high around 15 kolwatts. It was expected that an HTS magnet would dissipate around 1 watt, significantly reduce power consumption. The SPI team assembled to achieve this goal was led by Oxford Instruments, Superconducting Technology (OST), who developed the method of producing commercial dip coated tape. Superconductive Components Inc. (SCI), a leading US supplier of HTS powders, supported the conductor optimization through powder optimization, scaling, and cost reduction. Oxford Magnet Technology (OMT), a joint venture between Oxford Instruments and Siemens and the world’s leading supplier of MRI magnet systems, was involved to design and build the HTS MRI magnet and cryogenics. Siemens Magnetic Resonance Division, a leading developer and supplier of complete MRI imaging systems, was expected to integrate the final system and perform imaging trials. The original MRI demonstration project was ended in July 2004 by mutual consent of Oxford Instruments and Siemens. Between

  4. Bee assemblage in habitats associated with Brassica napus L.

    Directory of Open Access Journals (Sweden)

    Rosana Halinski

    2015-09-01

    Full Text Available ABSTRACTAssessments in agricultural crops indicate that alterations in the landscape adjacent to the crops can result in reduced productivity due to loss or low abundance of pollinating agents. In the canola crop, production is partially dependent on insect pollination. Therefore, knowledge of the faunal diversity within and near crop fields is key for the management of these insects and consequently for the increase in productivity. This study aimed to determine and compare the diversity of bees in habitats associated with canola fields in southern Brazil. Bees were captured in four agricultural areas using pan traps in three habitat classes: (1 flowering canola crop, (2 forest remnant, and (3 grassland vegetation. The highest abundance of bees was observed in the grassland vegetation (50% and in the flowering canola field (47%. Eight species common to the three habitat classes were recorded, four of which are represented by native social bees. In addition, a single or a few individuals represented species that were exclusive to a specific habitat class; eight species were collected exclusively in the interior of the canola field, 51 in the grassland vegetation, and six in the forest remnant. The majority of the rare species recorded exhibits subsocial or solitary behaviour and inhabit open places. The composition of bee groups differed between the habitats showing the importance of maintaining habitat mosaics with friendly areas for pollinators, which promote the pollination service for canola flowers.

  5. Genetically modified parthenocarpic eggplants: improved fruit productivity under both greenhouse and open field cultivation.

    Directory of Open Access Journals (Sweden)

    Pandolfini Tiziana

    2002-04-01

    Full Text Available Abstract Background Parthenocarpy, or fruit development in the absence of fertilization, has been genetically engineered in eggplant and in other horticultural species by using the DefH9-iaaM gene. The iaaM gene codes for tryptophan monoxygenase and confers auxin synthesis, while the DefH9 controlling regions drive expression of the gene specifically in the ovules and placenta. A previous greenhouse trial for winter production of genetically engineered (GM parthenocarpic eggplants demonstrated a significant increase (an average of 33% increase in fruit production concomitant with a reduction in cultivation costs. Results GM parthenocarpic eggplants have been evaluated in three field trials. Two greenhouse spring trials have shown that these plants outyielded the corresponding untransformed genotypes, while a summer trial has shown that improved fruit productivity in GM eggplants can also be achieved in open field cultivation. Since the fruits were always seedless, the quality of GM eggplant fruits was improved as well. RT-PCR analysis demonstrated that the DefH9-iaaM gene is expressed during late stages of fruit development. Conclusions The DefH9-iaaM parthenocarpic gene is a biotechnological tool that enhances the agronomic value of all eggplant genotypes tested. The main advantages of DefH9-iaaM eggplants are: i improved fruit productivity (at least 30–35% under both greenhouse and open field cultivation; ii production of good quality (marketable fruits during different types of cultivation; iii seedless fruit with improved quality. Such advantages have been achieved without the use of either male or female sterility genes.

  6. Open-field mouse brain PET: design optimisation and detector characterisation

    Science.gov (United States)

    Kyme, Andre Z.; Judenhofer, Martin S.; Gong, Kuang; Bec, Julien; Selfridge, Aaron; Du, Junwei; Qi, Jinyi; Cherry, Simon R.; Meikle, Steven R.

    2017-08-01

    Open-field’ PET, in which an animal is free to move within an enclosed space during imaging, is a very promising advance for neuroscientific research. It provides a key advantage over conventional imaging under anesthesia by enabling functional changes in the brain to be correlated with an animal’s behavioural response to environmental or pharmacologic stimuli. Previously we have demonstrated the feasibility of open-field imaging of rats using motion compensation techniques applied to a commercially available PET scanner. However, this approach of ‘retro-fitting’ motion compensation techniques to an existing system is limited by the inherent geometric and performance constraints of the system. The goal of this project is to develop a purpose-built PET scanner with geometry, motion tracking and imaging performance tailored and optimised for open-field imaging of the mouse brain. The design concept is a rail-based sliding tomograph which moves according to the animal’s motion. Our specific aim in this work was to evaluate candidate scanner designs and characterise the performance of a depth-of-interaction detector module for the open-field system. We performed Monte Carlo simulations to estimate and compare the sensitivity and spatial resolution performance of four scanner geometries: a ring, parallel plate, and two box variants. Each system was based on a detector block consisting of a 23  ×  23 array of 0.785  ×  0.785  ×  20 mm3 LSO crystals (overall dim. 19.6  ×  19.6  ×  20 mm). We found that a DoI resolution capability of 3 mm was necessary to achieve approximately uniform sub-millimetre spatial resolution throughout the FoV for all scanners except the parallel-plate geometry. With this DoI performance, the sensitivity advantage afforded by the box geometry with overlapping panels (16% peak absolute sensitivity, a 36% improvement over the ring design) suggests this unconventional design is best

  7. Level Truncation and Rolling the Tachyon in the Lightcone Basis for Open String Field Theory

    CERN Document Server

    Erler, T G

    2004-01-01

    A recent paper by Gross and Erler (hep-th/0406199) showed that by making a certain well-defined, unitary transformation on the mode basis for the open bosonic string--one that identifies the lightcone component of position with the string midpoint--it is possible to render the action for cubic string field theory local in lightcone time. In this basis, then, cubic string field theory possesses a well-defined initial value formulation and a conserved Hamiltonian. With this new understanding it seems natural to study time dependent solutions representing the the decay of an unstable D-branes. In this paper we study such solutions using level truncation of mode oscillators in the lightcone basis, finding both homogenous solutions by perturbatively expanding the string field in modes $e^{nt}$, and inhomogenous solutions by integrating the equations of motion on a lattice. Truncating the theory to level $(\\tilde{2},\\tilde{4})$ in $\\alpha^+$ oscillators, we find time dependent solutions whose behavior seems to conv...

  8. Towards an Open Software Platform for Field Robots in Precision Agriculture

    Directory of Open Access Journals (Sweden)

    Kjeld Jensen

    2014-06-01

    Full Text Available Robotics in precision agriculture has the potential to improve competitiveness and increase sustainability compared to current crop production methods and has become an increasingly active area of research. Tractor guidance systems for supervised navigation and implement control have reached the market, and prototypes of field robots performing precision agriculture tasks without human intervention also exist. But research in advanced cognitive perception and behaviour that is required to enable a more efficient, reliable and safe autonomy becomes increasingly demanding due to the growing software complexity. A lack of collaboration between research groups contributes to the problem. Scientific publications describe methods and results from the work, but little field robot software is released and documented for others to use. We hypothesize that a common open software platform tailored to field robots in precision agriculture will significantly decrease development time and resources required to perform experiments due to efficient reuse of existing work across projects and robot platforms. In this work we present the FroboMind software platform and evaluate the performance when applied to precision agriculture tasks.

  9. Flow Fields with Vortex in a Small Semi-open Axial Fan

    Institute of Scientific and Technical Information of China (English)

    Norimasa. Shiomi; Yoichi Kinoue; Ying zi Jin; Toshiaki Setoguchi; Kenji Kaneko

    2009-01-01

    In order to clarify the effect of tip clearance (TC) size on fan performance and the flow field at rotor outlet in a small semi-open axial fan, the experimental investigation was carried out. The tip diameter of test fan rotor was 180mm and test TC sizes were 1 mm (TC=1 mm) and 4mm (TC=4mm). Fan characteristics tests were carried out for two cases of TC size and three-dimensional velocity fields at rotor outlet were measured using a single slant hot-wire probe at four flow-rate conditions. As a result, it was found that the pressure -flow-rate characteristics curves for two cases showed almost the same tendency. However, the ensemble averaged velocity profiles along radial measurement stations of TC=4mm largely changed compared with that of TC=1mm in cases of small flow-rate condition. From the phase-locked averaging results, it was also found that the vortex existed in the rotor outlet flow field of high flow-rate condition for each TC case. Compared with the vortices for TC=1mm and TC=4mm, the vortex for TC=4mm was stronger than that for TC=1mm.

  10. Variable stars in the open cluster NGC 6791 and its surrounding field

    CERN Document Server

    De Marchi, F; Montalto, M; Piotto, G; Desidera, S; Bedin, L R; Claudi, R; Ferro, A Arellano; Bruntt, H; Stetson, P B

    2007-01-01

    Aims: This work presents a high--precision variability survey in the field of the old, super metal-rich open cluster NGC 6791. Methods: The data sample consists of more than 75,000 high-precision CCD time series measurements in the V band obtained mainly at the Canada-France-Hawaii Telescope, with additional data from S. Pedro Martir and Loiano observatories, over a time span of ten nights. The field covers an area of 42x28 arcmin^2. Results: We have discovered 260 new variables and re-determined periods and amplitudes of 70 known variable stars. By means of a photometric evaluation of the membership in NGC 6791, and a preliminary membership based on the proper motions, we give a full description of the variable content of the cluster and surrounding field in the range 16

  11. A comparison of subscription and open access journals in construction management and related fields

    Directory of Open Access Journals (Sweden)

    Bo-Christer Bjork

    2012-05-01

    Full Text Available The Internet has profoundly changed the technical infrastructure for the publishing of scientific peer reviewed journals. The traditional business model of selling the content to subscribers is increasingly being challenged by Open Access journals, which are either run at low cost by voluntary academics or which sell dissemination services to authors. In addition authors in many fields are taking advantage of the legal possibilities of uploading free manuscript versions to institutional or subject-based repositories, in order to increase readership and impact. Construction Management is lagging behind many other fields in utilising the potential of the web for efficient dissemination results, in particular to academics outside the leading universities in industrialised countries. This study looks closer at the current publishing situation in construction management and related fields and compares empirical data about 16 OA journals and 16 traditional subscription journals. Of the articles published in 2011 in the subscription journals only 9 % could be found as OA copies. The overall OA availability (including article in OA journals was 14 % for Construction Management and Economics and 29 for construction IT scholarship. 

  12. Did Open Solar Magnetic Field Increase during the Last 100 Years: A Reanalysis of Geomagnetic Activity

    CERN Document Server

    Mursula, K; Karinen, A

    2004-01-01

    Long-term geomagnetic activity presented by the aa index has been used to show that the heliospheric magnetic field has more than doubled during the last 100 years. However, serious concern has been raised on the long-term consistency of the aa index and on the centennial rise of the solar magnetic field. Here we reanalyze geomagnetic activity during the last 100 years by calculating the recently suggested IHV (Inter-Hour Variability) index as a measure of local geomagnetic activity for seven stations. We find that local geomagnetic activity at all stations follows the same qualitative long-term pattern: an increase from early 1900s to 1960, a dramatic dropout in 1960s and a (mostly weaker) increase thereafter. Moreover, at all stations, the activity at the end of the 20th century has a higher average level than at the beginning of the century. This agrees with the result based on the aa index that global geomagnetic activity, and thereby, the open solar magnetic field has indeed increased during the last 100...

  13. Nonequilibrium effective field theory for absorbing state phase transitions in driven open quantum spin systems

    Science.gov (United States)

    Buchhold, Michael; Everest, Benjamin; Marcuzzi, Matteo; Lesanovsky, Igor; Diehl, Sebastian

    2017-01-01

    Phase transitions to absorbing states are among the simplest examples of critical phenomena out of equilibrium. The characteristic feature of these models is the presence of a fluctuationless configuration which the dynamics cannot leave, which has proved a rather stringent requirement in experiments. Recently, a proposal to seek such transitions in highly tunable systems of cold-atomic gases offers to probe this physics and, at the same time, to investigate the robustness of these transitions to quantum coherent effects. Here, we specifically focus on the interplay between classical and quantum fluctuations in a simple driven open quantum model which, in the classical limit, reproduces a contact process, which is known to undergo a continuous transition in the "directed percolation" universality class. We derive an effective long-wavelength field theory for the present class of open spin systems and show that, due to quantum fluctuations, the nature of the transition changes from second to first order, passing through a bicritical point which appears to belong instead to the "tricritical directed percolation" class.

  14. Variable stars in the field of the open cluster NGC 7789

    CERN Document Server

    Mochejska, B J

    1999-01-01

    We present the results of our search for variable stars in the intermediate-age open cluster NGC 7789. We have found 45 variable stars: 35 eclipsing binaries, five pulsating variables and five miscellaneous variables. Most of the eclipsing binaries show W UMa type of variability, with periods shorter than one day. Four systems exhibit unusual behavior: two, V4276 and V6698, are probably RS CVn stars, another, V3283, is a possible cataclysmic binary. The nature of the fourth binary, V2130, is unclear: the system exhibits assymetric maxima. Among the pulsating variables two, V3407C and V4805 are background RR Lyrae stars and one, V6736, is a delta Scuti variable which is a blue straggler belonging to the cluster. Some of the miscellaneous variables may have periods longer than the five day timespan of our observations. We also present a color-magnitude diagram for the NGC 7789 open cluster, fairly complete down to V ~ 20. The relatively large number of variables found in the comparison field (14 compared to 31 ...

  15. From the Berkovits formulation to the Witten formulation in open superstring field theory

    CERN Document Server

    Iimori, Yuki; Okawa, Yuji; Torii, Shingo

    2014-01-01

    The Berkovits formulation of open superstring field theory is based on the large Hilbert space of the superconformal ghost sector. We discuss its relation to the Witten formulation based on the small Hilbert space. We introduce a one-parameter family of conditions for partial gauge fixing of the Berkovits formulation such that the cubic interaction of the theory under the partial gauge fixing reduces to that of the Witten formulation in a singular limit. The local picture-changing operator at the open-string midpoint in the Witten formulation is regularized in our approach, and the divergence in on-shell four-point amplitudes coming from collision of picture-changing operators is resolved. The quartic interaction inherited from the Berkovits formulation plays a role of adjusting different behaviors of the picture-changing operators in the $s$ channel and in the $t$ channel of Feynman diagrams with two cubic vertices, and correct amplitudes in the world-sheet theory are reproduced. While gauge invariance at th...

  16. From the Berkovits formulation to the Witten formulation in open superstring field theory

    Science.gov (United States)

    Iimori, Yuki; Noumi, Toshifumi; Okawa, Yuji; Torii, Shingo

    2014-03-01

    The Berkovits formulation of open superstring field theory is based on the large Hilbert space of the superconformal ghost sector. We discuss its relation to the Witten formulation based on the small Hilbert space. We introduce a one-parameter family of conditions for partial gauge fixing of the Berkovits formulation such that the cubic interaction of the theory under the partial gauge fixing reduces to that of the Witten formulation in a singular limit. The local picture-changing operator at the open-string midpoint in the Witten formulation is regularized in our approach, and the divergence in on-shell four-point amplitudes coming from collision of picture-changing operators is resolved. The quartic interaction inherited from the Berkovits formulation plays a role of adjusting different behaviors of the picture-changing operators in the s channel and in the t channel of Feynman diagrams with two cubic vertices, and correct amplitudes in the world-sheet theory are reproduced. While gauge invariance at the second order in the coupling constant is obscured in the Witten formulation by collision of picture-changing operators, it is well defined in our approach and is recovered by including the quartic interaction inherited from the Berkovits formulation.

  17. From the Berkovits formulation to the Witten formulation in open superstring field theory

    Energy Technology Data Exchange (ETDEWEB)

    Iimori, Yuki [Department of Physics, Nagoya University,Nagoya 464-8602 (Japan); Noumi, Toshifumi [Mathematical Physics Laboratory, RIKEN Nishina Center,Saitama 351-0198 (Japan); Okawa, Yuji [Institute of Physics, The University of Tokyo,Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Torii, Shingo [Mathematical Physics Laboratory, RIKEN Nishina Center,Saitama 351-0198 (Japan)

    2014-03-07

    The Berkovits formulation of open superstring field theory is based on the large Hilbert space of the superconformal ghost sector. We discuss its relation to the Witten formulation based on the small Hilbert space. We introduce a one-parameter family of conditions for partial gauge fixing of the Berkovits formulation such that the cubic interaction of the theory under the partial gauge fixing reduces to that of the Witten formulation in a singular limit. The local picture-changing operator at the open-string midpoint in the Witten formulation is regularized in our approach, and the divergence in on-shell four-point amplitudes coming from collision of picture-changing operators is resolved. The quartic interaction inherited from the Berkovits formulation plays a role of adjusting different behaviors of the picture-changing operators in the s channel and in the t channel of Feynman diagrams with two cubic vertices, and correct amplitudes in the world-sheet theory are reproduced. While gauge invariance at the second order in the coupling constant is obscured in the Witten formulation by collision of picture-changing operators, it is well defined in our approach and is recovered by including the quartic interaction inherited from the Berkovits formulation.

  18. Open Field Study of Some Zea mays Hybrids, Lipid Compounds and Fumonisins Accumulation

    Directory of Open Access Journals (Sweden)

    Paola Giorni

    2015-09-01

    Full Text Available Lipid molecules are increasingly recognized as signals exchanged by organisms interacting in pathogenic and/or symbiotic ways. Some classes of lipids actively determine the fate of the interactions. Host cuticle/cell wall/membrane components such as sphingolipids and oxylipins may contribute to determining the fate of host–pathogen interactions. In the present field study, we considered the relationship between specific sphingolipids and oxylipins of different hybrids of Zea mays and fumonisin by F. verticillioides, sampling ears at different growth stages from early dough to fully ripe. The amount of total and free fumonisin differed significantly between hybrids and increased significantly with maize ripening. Oxylipins and phytoceramides changed significantly within the hybrids and decreased with kernel maturation, starting from physiological maturity. Although the correlation between fumonisin accumulation and plant lipid profile is certain, the data collected so far cannot define a cause-effect relationship but open up new perspectives. Therefore, the question—“Does fumonisin alter plant lipidome or does plant lipidome modulate fumonisin accumulation?”—is still open.

  19. Scattering of Discrete States in Two Dimensional Open String Field Theory

    CERN Document Server

    Sevic, B U

    1993-01-01

    This is the second in a series of papers devoted to open string field theory in two dimensions. In this paper we aim to clarify the origin and the role of discrete physical states in the theory. To this end, we study interactions of discrete states and generic tachyons. In particular, we discuss at length four point amplitudes. We show that behavior of the correlation functions is governed by the number of generic tachyons involved and values of the kinematic invariants $s$, $t$ and $u$. Divergence of certain classes of correlators is shown to be the consequence of the fact certain kinematic invariants are non--positive integers in that case. Explicit examples are included. We check our results by standard conformal technique.

  20. Open and closed loop manipulation of charged microchiplets in an electric field

    Energy Technology Data Exchange (ETDEWEB)

    Lu, J. P., E-mail: jplu@parc.com; Thompson, J. D.; Whiting, G. L.; Biegelsen, D. K.; Raychaudhuri, S.; Lujan, R.; Veres, J.; Lavery, L. L.; Völkel, A. R.; Chow, E. M. [Palo Alto Research Center, Inc., 3333 Coyote Hill Rd., Palo Alto, California 94304 (United States)

    2014-08-04

    We demonstrate the ability to orient, position, and transport microchips (“chiplets”) with electric fields. In an open-loop approach, modified four phase traveling wave potential patterns manipulate chiplets in a dielectric solution using dynamic template agitation techniques. Repeatable parallel assembly of chiplets is demonstrated to a positional accuracy of 6.5 μm using electrodes of 200 μm pitch. Chiplets with dipole surface charge patterns are used to show that orientation can be controlled by adding unique charge patterns on the chiplets. Chip path routing is also demonstrated. With a closed-loop control system approach using video feedback, dielectric, and electrophoretic forces are used to achieve positioning accuracy of better than 1 μm with 1 mm pitch driving electrodes. These chip assembly techniques have the potential to enable future printer systems where inputs are electronic chiplets and the output is a functional electronic system.

  1. Maternal environment alters social interactive traits but not open-field behavior in Fischer 344 rats.

    Science.gov (United States)

    Yamamuro, Yutaka

    2008-10-01

    Although it is recognized that the genetic background governs behavioral phenotypes, environmental factors also play a critical role in the development of various behavioral processes. The maternal environment has a major impact on pups, and the cross-fostering procedure is used to determine the influence of early life experiences. The present study examined the influence of maternal environment on behavioral traits in inbred Fischer 344 (F344) rats. F344/DuCrlCrlj and Wistar (Crlj:WI) pups were fostered from postnatal day 1 as follows: Wistar pups raised by Wistar dams, F344 raised by Wistar, Wistar raised by F344, and F344 raised by F344. At 10 weeks of age, rats were randomly assigned to an open-field test and social interaction test. In the open-field test, irrespective of the rearing conditions, the activity during the first 1 min was significantly lower in F344 rats than in Wistar rats. Latency to the onset of movement showed no difference between groups. In the social interaction test, the recognition performance during the first 1 min in F344 raised by F344 was significantly shorter than that in the other groups. The onset of recognition to a novel social partner in F344 raised by F344 was significantly delayed, and the delay disappeared upon cross-fostering by Wistar dams. These results raise the possibility that the behavioral phenotype of F344 rats results from the interplay of genetic factors and maternal environment during early life, and that F344 rats are a strain with high susceptibility to rearing conditions for the formation of their emotionality.

  2. Effects of septal cholinergic lesion on rat exploratory behavior in an open-field

    Directory of Open Access Journals (Sweden)

    M.R. Lamprea

    2003-02-01

    Full Text Available The medial septum participates in the modulation of exploratory behavior triggered by novelty. Also, selective lesions of the cholinergic component of the septohippocampal system alter the habituation of rats to an elevated plus-maze without modifying anxiety indices. We investigated the effects of the intraseptal injection of the cholinergic immunotoxin 192 IgG-saporin (SAP on the behavior of rats in an open-field. Thirty-nine male Wistar rats (weight: 194-230 g were divided into three groups, non-injected controls and rats injected with either saline (0.5 µl or SAP (237.5 ng/0.5 µl. Twelve days after surgery, the animals were placed in a square open-field (120 cm and allowed to freely explore for 5 min. After the test, the rats were killed by decapitation and the septum, hippocampus and frontal cortex were removed and assayed for acetylcholinesterase activity. SAP increased acetylcholinesterase activity in the septum, hippocampus and frontal cortex and decreased the total distance run (9.15 ± 1.51 m in comparison to controls (13.49 ± 0.91 m. The time spent in the center and at the periphery was not altered by SAP but the distance run was reduced during the first and second minutes (2.43 ± 0.36 and 1.75 ± 0.34 m compared to controls (4.18 ± 0.26 and 3.14 ± 0.25 m. SAP-treated rats showed decreased but persistent exploration throughout the session. These results suggest that septohippocampal cholinergic mechanisms contribute to at least two critical processes, one related to the motivation to explore new environments and the other to the acquisition and storage of spatial information (i.e., spatial memory.

  3. Jet outflow and open field line measurements on the C-2U advanced beam-driven field-reversed configuration plasma experiment

    Science.gov (United States)

    Sheftman, D.; Gupta, D.; Roche, T.; Thompson, M. C.; Giammanco, F.; Conti, F.; Marsili, P.; Moreno, C. D.

    2016-11-01

    Knowledge and control of the axial outflow of plasma particles and energy along open-magnetic-field lines are of crucial importance to the stability and longevity of the advanced beam-driven field-reversed configuration plasma. An overview of the diagnostic methods used to perform measurements on the open field line plasma on C-2U is presented, including passive Doppler impurity spectroscopy, microwave interferometry, and triple Langmuir probe measurements. Results of these measurements provide the jet ion temperature and axial velocity, electron density, and high frequency density fluctuations.

  4. Interacting Open Bosonic String in the Proper-Time Gauge: Covariant Open Bosonic String Field Theory on Multiple D-Branes

    CERN Document Server

    Lee, Taejin

    2016-01-01

    We construct a covariant open bosonic string field theory on multiple D-branes, which reduces to a non-Abelian group Yang-Mills gauge theory in the zero-slope limit. Making use of the first quantized open bosonic string in the proper time gauge, we convert the string amplitudes given by the Polyakov path integrals on string world sheets into those of the second quantized theory. On multiple D-branes, the string field takes values in the Lie-algebra of $U(N)$ group and the three-string vertex function must be invariant under the global $U(N)$ transformation. This requirement together with the condition that the string field theory reduces to the non-Abelian gauge field theory in the zero-slope limit, uniquely determines the three-string vertex function. We also examine the effective four-string vertex diagrams generated perturbatively by the three-string vertex at tree level. In the zero-slope limit they reduce to the tree diagrams with four external gauge fields with an intermediate massless gauge field propa...

  5. Inexpensive, Low Power, Open-Source Data Logging in the Field

    Science.gov (United States)

    Sandell, C. T.; Wickert, A. D.

    2016-12-01

    Collecting a robust data set of environmental conditions with commercial equipment is often cost prohibitive. I present the ALog, a general-purpose, inexpensive, low-power, open-source data logger that has proven its durability on long-term deployments in the harsh conditions of high altitude glaciers and humid river deltas. The ALog was developed to fill the need for a capable, rugged, easy-to-use, inexpensive, open-source hardware targeted at long-term remote deployment in nearly any environment. Building on the popular Arduino platform, the hardware features a high-precision clock, full size SD card slot for high-volume data storage, screw terminals, six analog inputs, two digital inputs, one digital interrupt, 3.3V and 5V power outputs, and SPI and I2C communication capability. The design is focused on extremely low power consumption allowing the Alog to be deployed for years on a single set of common alkaline batteries. The power efficiency of the Alog eliminates the difficulties associated with field power collection including additional hardware and installation costs, dependence on weather conditions, possible equipment failure, and the transport of bulky/heavy equipment to a remote site. Battery power increases suitable data collection sites (too shaded for photovoltaics) and allows for low profile installation options (including underground). The ALog has gone through continuous development with over four years of successful data collection in hydrologic field research. Over this time, software support for a wide range of sensors has been made available such as ultrasonic rangefinders (for water level, snow accumulation and glacial melt), temperature sensors (air and groundwater), humidity sensors, pyranometers, inclinometers, rain gauges, soil moisture and water potential sensors, resistance-based tools to measure frost heave, and cameras that trigger on events. The software developed for use with the ALog allows simple integration of established

  6. Open Clusters as Probes of the Galactic Magnetic Field: I. Cluster Properties

    CERN Document Server

    Hoq, Sadia

    2015-01-01

    Stars in open clusters are powerful probes of the intervening Galactic magnetic field, via background starlight polarimetry, because they provide constraints on the magnetic field distances. We use 2MASS photometric data for a sample of 31 clusters in the outer Galaxy, for which near-IR polarimetric data were obtained, to determine the cluster distances, ages, and reddenings via fitting theoretical isochrones to cluster color-magnitude diagrams. The fitting approach uses an objective chi^2 minimization technique to derive the cluster properties and their uncertainties. We found the ages, distances, and reddenings for 24 of the clusters, and the distances and reddenings for six additional clusters that were either sparse or faint in the near-IR. The derived ranges of log(age), distance, and E(B-V) were 7.25-9.63, ~670-6160 pc, and 0.02-1.46 mag, respectively. The distance uncertainties ranged from ~8 to 20%. The derived parameters were compared to previous studies, and most cluster parameters agree within our ...

  7. Development of a Field-Aligned Integrated Conductivity Model Using the SAMI2 Open Source Code

    Science.gov (United States)

    Hildebrandt, Kyle; Gearheart, Michael; West, Keith

    2003-03-01

    The SAMI2 open source code is a middle and low latitude ionspheric model developed by the Naval Research Lab for the dual purposes of research and education. At the time of this writing the source code has no component for the integrated magnetic field-aligned conductivity. The dependence of human activities on conditions in the space environment, such as communications, has grown and will continue to do so. With this growth comes higher financial stakes, as changes in the space environment have greater economic impact. In order to minimize the adverse effects of these changes, predictive models are being developed. Among the geophysical parameters that affect communications is the conductivity in the ionosphere. As part of the commitment of Texas A & M Univeristy-Commerce to build a strong undergraduate research program, a team consisting of two students and a faculty mentor are developing a model of the integrated field-aligned conductivity using the SAMI2 code. The current status of the research and preliminary results are presented as well as a summary of future work.

  8. A New Catalog of Variable Stars in the Field of the Open Cluster M37

    CERN Document Server

    Chang, S -W; Hartman, J D

    2015-01-01

    We present a comprehensive re-analysis of stellar photometric variability in the field of the open cluster M37 following the application of a new photometry and de-trending method to MMT/Megacam image archive. This new analysis allows a rare opportunity to explore photometric variability over a broad range of time-scales, from minutes to a month. The intent of this work is to examine the entire sample of over 30,000 objects for periodic, aperiodic, and sporadic behaviors in their light curves. We show a modified version of the fast $\\chi^{2}$ periodogram algorithm (F$\\chi^{2}$) and change-point analysis (CPA) as tools for detecting and assessing the significance of periodic and non-periodic variations. The benefits of our new photometry and analysis methods are evident. A total of 2306 stars exhibit convincing variations that are induced by flares, pulsations, eclipses, starspots, and unknown causes in some cases. This represents a 60% increase in the number of variables known in this field. Moreover, 30 of t...

  9. Variable Stars in the Field of the Open Cluster NGC 2126

    CERN Document Server

    Liu, Shun-Fang; Zhang, Xiao-Bin; Wu, Jiang-Hua; Ma, Jun; Jiang, Zhao-Ji; Chen, Jian-Sheng; Zhou, Xu

    2009-01-01

    We report the results of a time-series CCD photometric survey of variable stars in the field of the open cluster NGC 2126. In about one square degree field covering the cluster, a total number of 21 variable candidates are detected during this survey, of which 16 are newly found. The periods, classifications and spectral types of 14 newly discovered variables are discussed, which consist of six eclipsing binaries systems, three pulsating variable stars, three long period variables, one RS CVn star, and one W UMa or $\\delta$ Scuti star. In addition, there are two variable candidates, the properties of which cannot be determined in this paper. By a method based on fitting spectral energy distributions(SEDs) of stars with theoretical ones, the membership probabilities and the fundamental parameters of this cluster are determined. As a result, five variables are probably members of NGC 2126. The fundamental parameters of the this cluster are determined as: the metallicity to be 0.008 $Z_\\odot$, the age $\\log(t)$=...

  10. Prediction of the diffuse-field transmission loss of interior natural-ventilation openings and silencers.

    Science.gov (United States)

    Bibby, Chris; Hodgson, Murray

    2017-01-01

    The work reported here, part of a study on the performance and optimal design of interior natural-ventilation openings and silencers ("ventilators"), discusses the prediction of the acoustical performance of such ventilators, and the factors that affect it. A wave-based numerical approach-the finite-element method (FEM)-is applied. The development of a FEM technique for the prediction of ventilator diffuse-field transmission loss is presented. Model convergence is studied with respect to mesh, frequency-sampling and diffuse-field convergence. The modeling technique is validated by way of predictions and the comparison of them to analytical and experimental results. The transmission-loss performance of crosstalk silencers of four shapes, and the factors that affect it, are predicted and discussed. Performance increases with flow-path length for all silencer types. Adding elbows significantly increases high-frequency transmission loss, but does not increase overall silencer performance which is controlled by low-to-mid-frequency transmission loss.

  11. New variable stars discovered in the fields of three Galactic open clusters using the VVV Survey

    CERN Document Server

    Palma, Tali; Dékány, Istvan; Clariá, Juan J; Alonso-García, Javier; Gramajo, Luciana V; Alegría, Sebastian Ramírez; Bonatto, Charles

    2016-01-01

    This project is a massive near-infrared (NIR) search for variable stars in highly reddened and obscured open cluster (OC) fields projected on regions of the Galactic bulge and disk. The search is performed using photometric NIR data in the $J$-, $H$- and $K_s$- bands obtained from the Vista Variables in the V\\'ia L\\'actea (VVV) Survey. We performed in each cluster field a variability search using Stetson's variability statistics to select the variable candidates. Later, those candidates were subjected to a frequency analysis using the Generalized Lomb-Scargle and the Phase Dispersion Minimization algorithms. The number of independent observations range between 63 and 73. The newly discovered variables in this study, 157 in total in three different known OCs, are classified based on their light curve shapes, periods, amplitudes and their location in the corresponding color-magnitude $(J-K_s,K_s)$ and color-color $(H-K_s,J-H)$ diagrams. We found 5 possible Cepheid stars which, based on the period-luminosity rel...

  12. Field portable low temperature porous layer open tubular cryoadsorption headspace sampling and analysis part II: Applications.

    Science.gov (United States)

    Harries, Megan; Bukovsky-Reyes, Santiago; Bruno, Thomas J

    2016-01-15

    This paper details the sampling methods used with the field portable porous layer open tubular cryoadsorption (PLOT-cryo) approach, described in Part I of this two-part series, applied to several analytes of interest. We conducted tests with coumarin and 2,4,6-trinitrotoluene (two solutes that were used in initial development of PLOT-cryo technology), naphthalene, aviation turbine kerosene, and diesel fuel, on a variety of matrices and test beds. We demonstrated that these analytes can be easily detected and reliably identified using the portable unit for analyte collection. By leveraging efficiency-boosting temperature control and the high flow rate multiple capillary wafer, very short collection times (as low as 3s) yielded accurate detection. For diesel fuel spiked on glass beads, we determined a method detection limit below 1 ppm. We observed greater variability among separate samples analyzed with the portable unit than previously documented in work using the laboratory-based PLOT-cryo technology. We identify three likely sources that may help explain the additional variation: the use of a compressed air source to generate suction, matrix geometry, and variability in the local vapor concentration around the sampling probe as solute depletion occurs both locally around the probe and in the test bed as a whole. This field-portable adaptation of the PLOT-cryo approach has numerous and diverse potential applications.

  13. True branched nostocalean cyanobacteria from tropical aerophytic habitats and molecular assessment of two species from field samples

    Directory of Open Access Journals (Sweden)

    Viviani Ferreira

    2013-03-01

    Full Text Available Aerophytic cyanobacteria are commonly found growing on rocks, tree trunks and soil, but the diversity of these organisms is still poorly known. This complex group is very problematic considering the taxonomic arrangement and species circumscription, especially when taking into account tropical populations. In this work, 20 samples of aerophytic cyanobacteria from 15 distinct sampling sites were collected along a tropical rainforest area at the São Paulo State (Brazil. Samples were dried at room temperature after the collection, and once in the laboratory, they were rehydrated and analyzed. The taxonomic study resulted in the record and description of nine species of true-branched cyanobacteria pertaining to the genera Spelaeopogon (one specie, Hapalosiphon (two species and Stigonema (six species. The similarity of the flora found when compared to surveys conducted in other geographical regions was relatively low. These differences could be addressed to ecological conditions of the habitats, to the extension of the area surveyed or even to taxonomic misinterpretations. The molecular assessment of 16S rDNA on the basis of field material was successful for two morphospecies, Hapalosiphon sp. and Stigonema ocellatum; however, their relationships with other populations and species revealed to be uncertain. The results of the floristic survey and of the molecular approach evidenced the fragile delimitation of some genera and species in the true branched group of cyanobacteria.Las bacterias aerofíticas crecen comúnmente en las rocas, troncos de árboles y el suelo, pero la diversidad de estos organismos todavía es poco conocida. Este complejo grupo es muy problématico considerando la disposición taxónomica y la circunscripción de las especies, especialmente cuando se toman en cuenta las poblaciones tropicales. En esta investigación, 20 muestras de cianobacterias aerofíticas de 15 distintos sitios de muestro fueron recolectadas a lo largo de

  14. OPEN CLUSTERS AS PROBES OF THE GALACTIC MAGNETIC FIELD. I. CLUSTER PROPERTIES

    Energy Technology Data Exchange (ETDEWEB)

    Hoq, Sadia; Clemens, D. P., E-mail: shoq@bu.edu, E-mail: clemens@bu.edu [Institute for Astrophysical Research, 725 Commonwealth Avenue, Boston University, Boston, MA 02215 (United States)

    2015-10-15

    Stars in open clusters are powerful probes of the intervening Galactic magnetic field via background starlight polarimetry because they provide constraints on the magnetic field distances. We use 2MASS photometric data for a sample of 31 clusters in the outer Galaxy for which near-IR polarimetric data were obtained to determine the cluster distances, ages, and reddenings via fitting theoretical isochrones to cluster color–magnitude diagrams. The fitting approach uses an objective χ{sup 2} minimization technique to derive the cluster properties and their uncertainties. We found the ages, distances, and reddenings for 24 of the clusters, and the distances and reddenings for 6 additional clusters that were either sparse or faint in the near-IR. The derived ranges of log(age), distance, and E(B−V) were 7.25–9.63, ∼670–6160 pc, and 0.02–1.46 mag, respectively. The distance uncertainties ranged from ∼8% to 20%. The derived parameters were compared to previous studies, and most cluster parameters agree within our uncertainties. To test the accuracy of the fitting technique, synthetic clusters with 50, 100, or 200 cluster members and a wide range of ages were fit. These tests recovered the input parameters within their uncertainties for more than 90% of the individual synthetic cluster parameters. These results indicate that the fitting technique likely provides reliable estimates of cluster properties. The distances derived will be used in an upcoming study of the Galactic magnetic field in the outer Galaxy.

  15. Field determination of multipollutant, open area combustion source emission factors with a hexacopter unmanned aerial vehicle

    Science.gov (United States)

    Aurell, J.; Mitchell, W.; Chirayath, V.; Jonsson, J.; Tabor, D.; Gullett, B.

    2017-10-01

    An emission sensor/sampler system was coupled to a National Aeronautics and Space Administration (NASA) hexacopter unmanned aerial vehicle (UAV) to characterize gases and particles in the plumes emitted from open burning of military ordnance. The UAV/sampler was tested at two field sites with test and sampling flights spanning over 16 h of flight time. The battery-operated UAV was remotely maneuvered into the plumes at distances from the pilot of over 600 m and at altitudes of up to 122 m above ground level. While the flight duration could be affected by sampler payload (3.2-4.6 kg) and meteorological conditions, the 57 sampling flights, ranging from 4 to 12 min, were typically terminated when the plume concentrations of CO2 were diluted to near ambient levels. Two sensor/sampler systems, termed ;Kolibri,; were variously configured to measure particulate matter, metals, chloride, perchlorate, volatile organic compounds, chlorinated dioxins/furans, and nitrogen-based organics for determination of emission factors. Gas sensors were selected based on their applicable concentration range, light weight, freedom from interferents, and response/recovery times. Samplers were designed, constructed, and operated based on U.S. Environmental Protection Agency (EPA) methods and quality control criteria. Results show agreement with published emission factors and good reproducibility (e.g., 26% relative standard deviation for PM2.5). The UAV/Kolibri represents a significant advance in multipollutant emission characterization capabilities for open area sources, safely and effectively making measurements heretofore deemed too hazardous for personnel or beyond the reach of land-based samplers.

  16. Window opening behaviour: simulations of occupant behaviour in residential buildings using models based on a field survey

    DEFF Research Database (Denmark)

    Valentina, Fabi; Andersen, Rune Korsholm; Corgnati, Stefano Paolo

    2012-01-01

    Window opening behaviour has been shown to have a significant impact on airflow rates and hence energy consumption. Nevertheless, the inhabitant behaviour related to window opening in residential buildings is currently poorly investigated through both field surveys and building energy simulations....... In particular, reliable information regarding user behaviour in residential buildings is crucial for suitable prediction of building performance (energy consumption, indoor environmental quality, etc.). To face this issue, measurements of indoor climate and outdoor environmental parameters and window “opening...... and closing” actions were performed in 15 dwellings from January to August 2008 in Denmark. Probabilistic models of inhabitants’ window “opening and closing” behaviour were developed and implemented in the energy simulation software IDA ICE to improve window opening and closing strategies in simulations...

  17. Pollination deficit in open-field tomato crops (Solanum lycopersicum L., Solanaceae in Rio de Janeiro state, Southeast Brazil

    Directory of Open Access Journals (Sweden)

    Mariana Scaramussa Deprá

    2014-02-01

    Full Text Available More than 70% of world’s crops benefit from biotic pollination, and bees are their main pollinators. Despite the fact that some of these insects have been broadly studied, understanding the interactions between plant crops and their pollinators with a local scale approach is necessary when aiming to apply proper protective and management measures to pollinators and their respective crops. In this context, we analyzed the pollination status of open-field tomato crops (Solanum lycopersicum L., regarding fruit-set, visitation rate and the quality of fruits. We recorded the formation of fruits through spontaneous self-pollination and open-pollination, and the occurrence of pollinators in 24 areas of open-field tomato crops. We performed experiments of apomixis, spontaneous self-pollination, manual cross pollination and supplemental cross pollination (simulating the pollinator behavior in a greenhouse. The fruit quality was evaluated according to circumference, weight, volume and number of seeds. Higher production of fruits after open-pollination compared to spontaneous self-pollination indicates the importance of pollinators to increment productivity of S. lycopersicum in the study area. The circumference and the number of seeds from tomatoes of the greenhouse plantation did not differ between spontaneous self-pollination and the manual cross pollination. In the open-field crops the number of seeds was higher for fruits resulting from open-pollination. Our results indicate that the importance of bees is mainly related to the increase in fruit production, thus incrementing the productivity of tomato crops.

  18. Pollination deficit in open-field tomato crops (Solanum lycopersicum L., Solanaceae in Rio de Janeiro state, Southeast Brazil

    Directory of Open Access Journals (Sweden)

    Maria Cristina Gaglianone

    2013-10-01

    Full Text Available More than 70% of world’s crops benefit from biotic pollination, and bees are their main pollinators. Despite the fact that some of these insects have been broadly studied, understanding the interactions between plant crops and their pollinators with a local scale approach is necessary when aiming to apply proper protective and management measures to pollinators and their respective crops. In this context, we analyzed the pollination status of open-field tomato crops (Solanum lycopersicum L., regarding fruit-set, visitation rate and the quality of fruits. We recorded the formation of fruits through spontaneous self-pollination and open-pollination, and the occurrence of pollinators in 24 areas of open-field tomato crops. We performed experiments of apomixis, spontaneous self-pollination, manual cross pollination and supplemental cross pollination (simulating the pollinator behavior in a greenhouse. The fruit quality was evaluated according to circumference, weight, volume and number of seeds. Higher production of fruits after open-pollination compared to spontaneous self-pollination indicates the importance of pollinators to increment productivity of S. lycopersicum in the study area. The circumference and the number of seeds from tomatoes of the greenhouse plantation did not differ between spontaneous self-pollination and the manual cross pollination. In the open-field crops the number of seeds was higher for fruits resulting from open-pollination. Our results indicate that the importance of bees is mainly related to the increase in fruit production, thus incrementing the productivity of tomato crops.

  19. Open Imaging Nephelometer Scattering Measurements from the 2014 Discover-AQ Field Mission

    Science.gov (United States)

    Espinosa, R.; Orozco, D.; Dolgos, G.; Martins, J. V.

    2014-12-01

    After greenhouse gases, aerosols are thought to have the largest contribution to total atmospheric radiative forcing, but they are frequently cited as the single largest source of uncertainty among all anthropogenic radiative forcing components. Remote sensing allows for global measurements of aerosol properties, however validation of these measurements and the climatological assumptions used in their retrieval algorithms require high quality in situ sampling. The Laboratory for Aerosols, Clouds and Optics (LACO) at the University of Maryland Baltimore County (UMBC) has developed the Imaging Nephelometer, a novel and highly accurate instrument concept designed to significantly aid in situ optical scattering measurements. Imaging Nephelometers allow for measurements of scattering coefficient, phase function and polarized phase function over a wide angular range of 2 to 178 degrees with an angular resolution of less than half of a degree. The simple layout of these devices also permits the construction of an instrument that is compact enough to be deployed on a variety of airborne platforms. Additionally, a version of this instrument that is capable of in situ sampling in open-air, free from sample biases potentially introduced by an inlet or containment apparatus, has recently been constructed. This instrument, known as the Open Imaging NEPHelometer (OI-NEPH), was flown on the P3 aircraft in the summer of 2014 during the Colorado portion of the Discover-AQ field mission (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality). This presentation will focus on the results of the OI-NEPH's successful science flights during this field experiment. The P3's flights during this mission focused primarily on vehicle, agriculture, biomass burning and industrial processing emissions over the Colorado Front Range. Emphasis will be placed on any observed differences in scattering properties between the measurements

  20. Habitat Suitability Index Models: Eastern wild turkey

    Science.gov (United States)

    Schroeder, Richard L.

    1985-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the eastern wild turkey (Meleagris gallopavo sylvestris). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  1. Habitat Suitability Index Models: Swamp rabbit

    Science.gov (United States)

    Allen, Arthur W.

    1985-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the swamp rabbit (Sylvilagus aquaticus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  2. THE FIELD STUDY AS AN EDUCATIONAL TECHNIQUE IN OPEN AND DISTANCE LEARNING

    Directory of Open Access Journals (Sweden)

    Paraskevi VASSALA

    2006-10-01

    Full Text Available The main characteristic of Distance Learning is that the student is taught and learns without his tutor’s physical presence in the classroom. The opportunity for a direct (face to face communication between all members of the educational group [tutor counselor (TC and students] in Distance Learning is offered by the Tutorials/Contact Sessions (CS. Although these CSs are not compulsory, it is estimated that they are of high importance, since among other things, they help in clarifying difficult to understand points and they also help in the cognitive subject becoming more fully comprehensible by the student (Holmberg 1995. For the discussion of the various issues at the CSs many different educational techniques within the framework of adult education such as teamwork, short lectures, debates, questions and answers, case studies, simulations, role play, etc are used in combination. These are techniques raising the student’s interest, facilitating his/her participation in the learning process and developing interaction between TC and students and between students themselves. They also create a learning and research environment; encourage the students to work in a group and to learn by acting (Kokkos 1998. One of these educational techniques is the field study, which is the subject of this paper. To this day, no research has been carried out for the possibility of implementation of this technique in Distance Learning nor have any results of such implementation been studied. This paper comprising of three parts contains a general presentation of the field study as a teaching technique in the first part while in the second part the successive stages of development of this technique in Distance Learning are analyzed. Finally, in the third part the students’ views of Hellenic Open University on this technique are presented.

  3. New variable stars discovered in the fields of three Galactic open clusters using the VVV survey

    Science.gov (United States)

    Palma, T.; Minniti, D.; Dékány, I.; Clariá, J. J.; Alonso-García, J.; Gramajo, L. V.; Ramírez Alegría, S.; Bonatto, C.

    2016-11-01

    This project is a massive near-infrared (NIR) search for variable stars in highly reddened and obscured open cluster (OC) fields projected on regions of the Galactic bulge and disk. The search is performed using photometric NIR data in the J-, H- and Ks- bands obtained from the Vista Variables in the Vía Láctea (VVV) Survey. We performed in each cluster field a variability search using Stetson's variability statistics to select the variable candidates. Later, those candidates were subjected to a frequency analysis using the Generalized Lomb-Scargle and the Phase Dispersion Minimization algorithms. The number of independent observations range between 63 and 73. The newly discovered variables in this study, 157 in total in three different known OCs, are classified based on their light curve shapes, periods, amplitudes and their location in the corresponding color-magnitude (J -Ks ,Ks) and color-color (H -Ks , J - H) diagrams. We found 5 possible Cepheid stars which, based on the period-luminosity relation, are very likely type II Cepheids located behind the bulge. Among the newly discovered variables, there are eclipsing binaries, δ Scuti, as well as background RR Lyrae stars. Using the new version of the Wilson & Devinney code as well as the "Physics Of Eclipsing Binaries" (PHOEBE) code, we analyzed some of the best eclipsing binaries we discovered. Our results show that these studied systems turn out to be ranging from detached to double-contact binaries, with low eccentricities and high inclinations of approximately 80°. Their surface temperatures range between 3500 K and 8000 K.

  4. Using possibilities of some agricultural wastes in open-field banana cultivation

    Directory of Open Access Journals (Sweden)

    Mehmet ÖTEN

    2016-06-01

    Full Text Available Usage of farmyard manure is the one of the major factors to increase production cost in banana cultivation. Besides increasing the production costs, other disadvantages of farmyard manure are playing active role on carrying diseases and pests and also difficulty in obtaining. Due to the stated disadvantages, the use farmyard manure of banana farmers is decreasing. Therefore, we need alternative ways to increase the organic matter capacity of the soil. The effects of alternative applications to farmyard manure, namely banana waste and mushroom compost were investigated. The objective of the study was to evaluate effects of these applications on some morphological properties (plant height, plant circumference and number of leaves, yield (number of hands, number of fingers, bunch weight, finger weight and length and quality properties (flesh/skin ratio, total soluble solids matter, sugars etc. under open-field banana cultivation. The experiment was conducted in Kargıcak location of Alanya in randomized complete block design (RCBD with 3 replications. Experimental results revealed that using of farmyard manure and waste treatments positively affected the yield parameters like the number of hands and fingers, finger length, finger weight and bunch weight. On the other hand, treatments did not have a statistically significant effect on fruit quality parameters like soluble solids content, titratable acidity, pH and ash.

  5. OPSO - The OpenGL based Field Acquisition and Telescope Guiding System

    Science.gov (United States)

    Škoda, P.; Fuchs, J.; Honsa, J.

    2006-07-01

    We present OPSO, a modular pointing and auto-guiding system for the coudé spectrograph of the Ondřejov observatory 2m telescope. The current field and slit viewing CCD cameras with image intensifiers are giving only standard TV video output. To allow the acquisition and guiding of very faint targets, we have designed an image enhancing system working in real time on TV frames grabbed by BT878-based video capture card. Its basic capabilities include the sliding averaging of hundreds of frames with bad pixel masking and removal of outliers, display of median of set of frames, quick zooming, contrast and brightness adjustment, plotting of horizontal and vertical cross cuts of seeing disk within given intensity range and many more. From the programmer's point of view, the system consists of three tasks running in parallel on a Linux PC. One C task controls the video capturing over Video for Linux (v4l2) interface and feeds the frames into the large block of shared memory, where the core image processing is done by another C program calling the OpenGL library. The GUI is, however, dynamically built in Python from XML description of widgets prepared in Glade. All tasks are exchanging information by IPC calls using the shared memory segments.

  6. Amnesia of inhibitory avoidance by scopolamine is overcome by previous open-field exposure

    Science.gov (United States)

    Colettis, Natalia C.; Snitcofsky, Marina; Kornisiuk, Edgar E.; Gonzalez, Emilio N.; Quillfeldt, Jorge A.

    2014-01-01

    The muscarinic cholinergic receptor (MAChR) blockade with scopolamine either extended or restricted to the hippocampus, before or after training in inhibitory avoidance (IA) caused anterograde or retrograde amnesia, respectively, in the rat, because there was no long-term memory (LTM) expression. Adult Wistar rats previously exposed to one or two open-field (OF) sessions of 3 min each (habituated), behaved as control animals after a weak though over-threshold training in IA. However, after OF exposure, IA LTM was formed and expressed in spite of an extensive or restricted to the hippocampus MAChR blockade. It was reported that during and after OF exposure and reexposure there was an increase in both hippocampal and cortical ACh release that would contribute to “prime the substrate,” e.g., by lowering the synaptic threshold for plasticity, leading to LTM consolidation. In the frame of the “synaptic tagging and capture” hypothesis, plasticity-related proteins synthesized during/after the previous OF could facilitate synaptic plasticity for IA in the same structure. However, IA anterograde amnesia by hippocampal protein synthesis inhibition with anisomycin was also prevented by two OF exposures, strongly suggesting that there would be alternative interpretations for the role of protein synthesis in memory formation and that another structure could also be involved in this “OF effect.” PMID:25322799

  7. Open-source tools for dynamical analysis of Liley's mean-field cortex model

    CERN Document Server

    Green, Kevin R

    2012-01-01

    Mean-field models of the mammalian cortex treat this part of the brain as a two-dimensional excitable medium. The electrical potentials, generated by the excitatory and inhibitory neuron populations, are described by nonlinear, coupled, partial differential equations, that are known to generate complicated spatio-temporal behaviour. We focus on the model by Liley {\\sl et al.} (Network: Comput. Neural Syst. (2002) 13, 67-113). Several reductions of this model have been studied in detail, but a direct analysis of its spatio-temporal dynamics has, to the best of our knowledge, never been attempted before. Here, we describe the implementation of implicit time-stepping of the model and the tangent linear model, and solving for equilibria and time-periodic solutions, using the open-source library PETSc. By using domain decomposition for parallelization, and iterative solving of linear problems, the code is capable of parsing some dynamics of a macroscopic slice of cortical tissue with a sub-millimetre resolution.

  8. Mitigation of marine biofouling on tubes of open rack vaporizers using electromagnetic fields.

    Science.gov (United States)

    Trueba, Alfredo; Vega, Luis M; García, Sergio; Otero, Félix M; Madariaga, Ernesto

    2016-01-01

    This study quantitatively evaluates the antifouling action of the continuous physical treatment with electromagnetic fields (EMFs) of seawater used as heat exchanger fluid in an open rack vaporizer (ORV) pilot plant to reduce the growth of biofouling on external rib-tube surfaces. The results demonstrate that the biofilm adhered on the treated rib-tubes was reduced by 33% in thickness and by 44% in dissolved solids regarding the biofilm adhered on the untreated control rib-tubes. The lower conductivity and Ca(2+) and Mg(2+) ionic content in the effluent of the treated seawater confirmed that the EMFs accelerated the process of ionic calcium nucleation and precipitation as calcium carbonate. The precipitation of ions dissolved affected the inter-molecular interactions among extracellular polymers, thereby weakening the biofouling film matrix and reducing its adhesion capacity. The drag of small particles by the flow of seawater had an erosive action and decreased the biofouling film thickness. Consequently, the antifouling methods treatment with EMFs allowed reduce the negative effect that the biofouling have for the heat transfer equipment used in the regasification process and keep the highest techno-economic operating conditions.

  9. Pharmacological differences between memory consolidation of habituation to an open field and inhibitory avoidance learning

    Directory of Open Access Journals (Sweden)

    Vianna M.R.M.

    2001-01-01

    Full Text Available Rats implanted bilaterally with cannulae in the CA1 region of the dorsal hippocampus or the entorhinal cortex were submitted to either a one-trial inhibitory avoidance task, or to 5 min of habituation to an open field. Immediately after training, they received intrahippocampal or intraentorhinal 0.5-µl infusions of saline, of a vehicle (2% dimethylsulfoxide in saline, of the glutamatergic N-methyl-D-aspartate (NMDA receptor antagonist 2-amino-5-phosphono pentanoic acid (AP5, of the protein kinase A inhibitor Rp-cAMPs (0.5 µg/side, of the calcium-calmodulin protein kinase II inhibitor KN-62, of the dopaminergic D1 antagonist SCH23390, or of the mitogen-activated protein kinase kinase inhibitor PD098059. Animals were tested in each task 24 h after training. Intrahippocampal KN-62 was amnestic for habituation; none of the other treatments had any effect on the retention of this task. In contrast, all of them strongly affected memory of the avoidance task. Intrahippocampal Rp-cAMPs, KN-62 and AP5, and intraentorhinal Rp-cAMPs, KN-62, PD098059 and SCH23390 caused retrograde amnesia. In view of the known actions of the treatments used, the present findings point to important biochemical differences in memory consolidation processes of the two tasks.

  10. Advanced Discontinuous Galerkin Algorithms and First Open-Field Line Turbulence Simulations

    Science.gov (United States)

    Hammett, G. W.; Hakim, A.; Shi, E. L.

    2016-10-01

    New versions of Discontinuous Galerkin (DG) algorithms have interesting features that may help with challenging problems of higher-dimensional kinetic problems. We are developing the gyrokinetic code Gkeyll based on DG. DG also has features that may help with the next generation of Exascale computers. Higher-order methods do more FLOPS to extract more information per byte, thus reducing memory and communications costs (which are a bottleneck at exascale). DG uses efficient Gaussian quadrature like finite elements, but keeps the calculation local for the kinetic solver, also reducing communication. Sparse grid methods might further reduce the cost significantly in higher dimensions. The inner product norm can be chosen to preserve energy conservation with non-polynomial basis functions (such as Maxwellian-weighted bases), which can be viewed as a Petrov-Galerkin method. This allows a full- F code to benefit from similar Gaussian quadrature as used in popular δf gyrokinetic codes. Consistent basis functions avoid high-frequency numerical modes from electromagnetic terms. We will show our first results of 3 x + 2 v simulations of open-field line/SOL turbulence in a simple helical geometry (like Helimak/TORPEX), with parameters from LAPD, TORPEX, and NSTX. Supported by the Max-Planck/Princeton Center for Plasma Physics, the SciDAC Center for the Study of Plasma Microturbulence, and DOE Contract DE-AC02-09CH11466.

  11. The relationship among oceanography, prey fields, and beaked whale foraging habitat in the Tongue of the Ocean.

    Directory of Open Access Journals (Sweden)

    Elliott L Hazen

    Full Text Available Beaked whales, specifically Blainville's (Mesoplodon densirostris and Cuvier's (Ziphius cavirostris, are known to feed in the Tongue of the Ocean, Bahamas. These whales can be reliably detected and often localized within the Atlantic Undersea Test and Evaluation Center (AUTEC acoustic sensor system. The AUTEC range is a regularly spaced bottom mounted hydrophone array covering >350 nm(2 providing a valuable network to record anthropogenic noise and marine mammal vocalizations. Assessments of the potential risks of noise exposure to beaked whales have historically occurred in the absence of information about the physical and biological environments in which these animals are distributed. In the fall of 2008, we used a downward looking 38 kHz SIMRAD EK60 echosounder to measure prey scattering layers concurrent with fine scale turbulence measurements from an autonomous turbulence profiler. Using an 8 km, 4-leaf clover sampling pattern, we completed a total of 7.5 repeat surveys with concurrently measured physical and biological oceanographic parameters, so as to examine the spatiotemporal scales and relationships among turbulence levels, biological scattering layers, and beaked whale foraging activity. We found a strong correlation among increased prey density and ocean vertical structure relative to increased click densities. Understanding the habitats of these whales and their utilization patterns will improve future models of beaked whale habitat as well as allowing more comprehensive assessments of exposure risk to anthropogenic sound.

  12. The relationship among oceanography, prey fields, and beaked whale foraging habitat in the Tongue of the Ocean.

    Science.gov (United States)

    Hazen, Elliott L; Nowacek, Douglas P; St Laurent, Louis; Halpin, Patrick N; Moretti, David J

    2011-04-27

    Beaked whales, specifically Blainville's (Mesoplodon densirostris) and Cuvier's (Ziphius cavirostris), are known to feed in the Tongue of the Ocean, Bahamas. These whales can be reliably detected and often localized within the Atlantic Undersea Test and Evaluation Center (AUTEC) acoustic sensor system. The AUTEC range is a regularly spaced bottom mounted hydrophone array covering >350 nm(2) providing a valuable network to record anthropogenic noise and marine mammal vocalizations. Assessments of the potential risks of noise exposure to beaked whales have historically occurred in the absence of information about the physical and biological environments in which these animals are distributed. In the fall of 2008, we used a downward looking 38 kHz SIMRAD EK60 echosounder to measure prey scattering layers concurrent with fine scale turbulence measurements from an autonomous turbulence profiler. Using an 8 km, 4-leaf clover sampling pattern, we completed a total of 7.5 repeat surveys with concurrently measured physical and biological oceanographic parameters, so as to examine the spatiotemporal scales and relationships among turbulence levels, biological scattering layers, and beaked whale foraging activity. We found a strong correlation among increased prey density and ocean vertical structure relative to increased click densities. Understanding the habitats of these whales and their utilization patterns will improve future models of beaked whale habitat as well as allowing more comprehensive assessments of exposure risk to anthropogenic sound.

  13. Coherent time evolution of highly excited Rydberg states in pulsed electric field Opening a stringent way to selectively field-ionize the highly excited states

    CERN Document Server

    Tada, M; Ogawa, I; Funahashi, H; Yamamoto, K; Matsuki, S

    2000-01-01

    Coherent time evolution of highly excited Rydberg states in Rb (98 < n < 150) under pulsed electric field in high slew-rate regime was investigated with the field ionization detection. The electric field necessary to ionize the Rydberg states was found to take discrete values successively depending on the slew rate. Specifically the slew-rate dependence of the ionization field varies with the quantum defect value of the states, i.e. with the energy position of the states relative to the adjacent manifold. This discrete transitional behavior of the ionization field observed for the first time is considered to be a manifestation of the strong coherence effect in the time evolution of the Rydberg states in pulsed electric field and opens a new effective way to stringently select a low-l state from the nearby states by field ionization.

  14. An Investigation of the Mechanism of Traumatic Brain Injury Caused by Blast in the Open Field

    Science.gov (United States)

    Feng, Ke

    Blast-induced traumatic brain injury (bTBI) is a signature wound of modern warfare. The current incomplete understanding of its injury mechanism impedes the development of strategies for effective protection of bTBI. Despite a considerable amount of experimental animal studies focused on the evaluation of brain neurotrauma caused by blast exposure, there is very limited knowledge on the biomechanical responses of the gyrenecephalic brain subjected to primary free-field blast waves imposed in vivo, and the correlation analysis between the biomechanical responses and its injury outcomes. Such information is crucial to the development of injury criteria of bTBI. This study aims to evaluate the external and internal mechanical responses of the brain against different levels of blast loading with Yucatan swine in free field, and to conduct correlational studies with brain tissue damage. To better understand primary bTBI, we have implemented an open field experimental model to apply controlled shock waves on swine head. The applied pressure levels of shock waves were predicted by finite element modeling and verified with calibrated testing. Biomechanical responses of primary blasts such as intracranial pressure (ICP), head kinetics, strain rate of skull, were measured in vivo during the blasts. A positive correlation between incident overpressure (IOP) and its corresponding biomechanical responses of the brain was observed. A parallel group of non-instrumented animals were used to collect injury data 72 hours post experiment. Cellular responses governed by primary blasts, such as neuronal degeneration and apoptosis were studied via immunohistochemistry. Representative fluorescent-stained images were examined under microscope. A positive correlation was found between the amount of degenerative neurons and the blast level. Significant elevation of apoptosis was found in the high-level blast. Comparisons between brains with varies ICP readings demonstrate differences of the

  15. Discovery of 13 New Variable Stars in the Field of the Open Cluster NGC 2168 (M35)

    Institute of Scientific and Technical Information of China (English)

    Juei-Hwa Hu; Wing-Huen Ip; Xiao-Bin Zhang; Zhao-Ji Jiang; Jun Ma; Xu Zhou

    2005-01-01

    A wide-field time-series CCD photometric survey of variable stars in the field of the open cluster NGC 2168 was carried out using the BATC Schmidt telescope. In total 13 new variable stars are discovered with three W UMa systems,one EA type and two EB type eclipsing binaries (one of them could be a W UMa system), and seven pulsating stars including three candidates of δ Scuti stars.

  16. About Frequency Characteristics of Electric Fields of Cylindrical Piezoceramic Antenna with Screen in the Form of an Open Ring Layer

    Directory of Open Access Journals (Sweden)

    Z.T. Gusak

    2016-03-01

    Full Text Available According to rigorous method of “related” fields the analytical expressions to describe electric fields of piezoceramic cylindrical antennas with screen in the form of an open ring layer of finite thickness was obtained. As a result of numerical analysis the quantity relations and the features of frequency characteristics of the electric current and the input impedance of the antenna with screen depending on the parameters of the antenna elements were found.

  17. Habitat Selection

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data provide information on the relationship between California red-legged frogs and their habitat in a unique ecosystem to better conserve this threatened...

  18. Habitat Observations

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data provide information on the relationship between California red-legged frogs and their habitat in a unique ecosystem to better conserve this threatened...

  19. Habitat heterogeneity drives the host-diversity-begets-parasite-diversity relationship: evidence from experimental and field studies.

    Science.gov (United States)

    Johnson, Pieter T J; Wood, Chelsea L; Joseph, Maxwell B; Preston, Daniel L; Haas, Sarah E; Springer, Yuri P

    2016-07-01

    Despite a century of research into the factors that generate and maintain biodiversity, we know remarkably little about the drivers of parasite diversity. To identify the mechanisms governing parasite diversity, we combined surveys of 8100 amphibian hosts with an outdoor experiment that tested theory developed for free-living species. Our analyses revealed that parasite diversity increased consistently with host diversity due to habitat (i.e. host) heterogeneity, with secondary contributions from parasite colonisation and host abundance. Results of the experiment, in which host diversity was manipulated while parasite colonisation and host abundance were fixed, further reinforced this conclusion. Finally, the coefficient of host diversity on parasite diversity increased with spatial grain, which was driven by differences in their species-area curves: while host richness quickly saturated, parasite richness continued to increase with neighbourhood size. These results offer mechanistic insights into drivers of parasite diversity and provide a hierarchical framework for multi-scale disease research.

  20. Caffeine and sleep-deprivation mediated changes in open-field behaviours, stress response and antioxidant status in mice

    Directory of Open Access Journals (Sweden)

    J. Olakunle Onaolapo

    2016-07-01

    Conclusion: Repeated caffeine consumption and/or acute sleep-deprivation led to significant changes in pattern of open-field behaviour and stress/antioxidant response in mice. Responses seen in the study are probably due to modulatory effects of caffeine on the total body response to stressful stimuli.

  1. Electroantennogram responses of tsetse flies (Glossina pallidipes) to host odours in an open field and riverine woodland

    NARCIS (Netherlands)

    Voskamp, K.E; den Otter, C.J; Noorman, N

    1998-01-01

    The present study was initiated to gain insight into the way in which tsetse flies (Glossina spp.) sense odours at different locations in odour plumes in both an open field and a wooded area. We recorded the antennal responses (EAGs) from stationary living female G. pallidipes 15 m upwind and at var

  2. Centimetre-precision guidance of moving implements in the open field: a simulation based on GPS measurements.

    NARCIS (Netherlands)

    Dijksterhuis, H.L.; Willigenburg, van L.G.; Zuydam, van R.P.

    1998-01-01

    High quality and sustainable agricultural production in the open field will be supported by centimetre-precision guidance of agricultural implements. In this paper, a complete guidance system is proposed and simulated using real sensor data obtained from a real time kinematic (RTK) differential glob

  3. The stimulatory effects of caffeine with oseltamivir (Tamiflu) on light-dark behavior and open-field behavior in mice.

    Science.gov (United States)

    Uchiyama, Hidemori; Toda, Akihisa; Imoto, Masumi; Nishimura, Satoko; Kuroki, Hiroaki; Soeda, Shinji; Shimeno, Hiroshi; Watanabe, Shigenori; Eyanagi, Reiko

    2010-01-22

    Abnormal behaviors and death associated with the use of oseltamivir (Tamiflu) have emerged as a major issue in influenza patients taking the drug. Here, we investigated the mechanisms underlying the effects of oseltamivir on the behavior of mice using light-dark and open-field preference tests. Oseltamivir (75 and 150 mg/kg, intraperitoneally (i.p.)) alone affected neither time spent in the open area in the light-dark preference test nor ambulation in the open-field test at 2h post-injection. However, a non-selective adenosine A(1)/A(2) receptor antagonist, caffeine (10mg/kg, i.p.) in combination with oseltamivir (150 mg/kg, i.p.) increased time spent in the open area in the light-dark preference test. This enhancement was not inhibited by a benzodiazepine receptor antagonist, flumazenil (10-20mg/kg, subcutaneously (s.c.)). Enhancement of ambulation in the open-field test was also observed when caffeine (10mg/kg, i.p.) was combined with oseltamivir (150 mg/kg, i.p.). This enhancement was inhibited by a dopamine D(2) receptor antagonist, haloperidol (0.1mg/kg, s.c.). Furthermore, an adenosine A(2) receptor antagonist, SCH58261 (3mg/kg, i.p.) in combination with oseltamivir (150 mg/kg, i.p.) increased ambulation in the open-field test, while an adenosine A(1) receptor antagonist, DPCPX (1-3mg/kg, i.p.) did not. These findings suggest that the actions of oseltamivir may involve the dopamine and adenosine systems. Our findings suggest that due to the interaction between central blockade of adenosine A(2) receptors by caffeine, and oseltamivir-induced behavioral changes, patients being treated with oseltamivir should be closely monitored.

  4. Axial Myopia Is Associated with Visual Field Prognosis of Primary Open-Angle Glaucoma.

    Directory of Open Access Journals (Sweden)

    Chen Qiu

    Full Text Available To identify whether myopia was associated with the visual field (VF progression of primary open-angle glaucoma (POAG.A total of 270 eyes of 270 POAG followed up for more than 3 years with ≥9 reliable VFs by Octopus perimetry were retrospectively reviewed. Myopia was divided into: mild myopia (-2.99 diopter [D], 0, moderate myopia (-5.99, 3.00 D, marked myopia (-9.00, -6.00 D and non-myopia (0 D or more. An annual change in the mean defect (MD slope >0.22 dB/y and 0.30 dB/y was defined as fast progression, respectively. Logistic regression was performed to determine prognostic factors for VF progression.For the cutoff threshold at 0.22 dB/y, logistic regression showed that vertical cup-to-disk ratio (VCDR; p = 0.004 and the extent of myopia (p = 0.002 were statistically significant. When logistic regression was repeated after excluding the extent of myopia, axial length (AL; p = 0.008, odds ratio [OR] = 0.796 reached significance, as did VCDR (p = 0.001. Compared to eyes with AL≤23 mm, the OR values were 0.334 (p = 0.059, 0.309 (p = 0.044, 0.266 (p = 0.019, 0.260 (p = 0.018, respectively, for 23 26 mm. The significance of vertical cup-to-disk ratio of (p = 0.004 and the extent of myopia (p = 0.008 did not change for the cutoff threshold at 0.30dB/y.VCDR and myopia were associated with VF prognosis of POAG. Axial myopia may be a protective factor against VF progression.

  5. Effects of Open-field Warming and Precipitation Manipulation on the Growth of Pinus densiflora Seedlings

    Science.gov (United States)

    Park, M. J.; Yoon, S. J.; Han, S. H.; Yun, H. M.; Chang, H.; Son, Y.

    2014-12-01

    The objective of this study was to investigate the effects of open-field artificial warming and precipitation manipulation on Pinus densiflora seedling growth. The temperature in warming plots have been set to be 3°C higher than control plots using infrared lamps since April, 2013. Precipitation manipulation consisted of precipitation decrease plots (-30%) with deployment of rain-capturing transparent panels, precipitation increase plots (+30%) with pump installation and drip-irrigation, and control plots. Two-year-old P. densiflora seedlings were planted in April, 2013. Seedling height and root collar diameter were measured in April and November, 2013 and April, 2014, and biomass were measured in April, 2013 and April, 2014. During the period of April to November, 2013, increments of seedling height and root collar diameter were not significantly different between control and warming plots. However, in April, 2014 seedling heights, new shoot lengths and weights were higher in warming plots than in control plots, with all precipitation manipulation treatments (pdensiflora. Lower shoot to root ratio in warming plots with precipitation decrease treatment might be resulted from water stress. In previous studies about artificial warming and/or precipitation manipulation, the effects were increase, decrease or no difference in growth. As these results suggest, responses of growth are species-specific and/or are dependent on the stage of growth and the treatment types of climate change experiments. Therefore, to examine the effects of climate changes on plant growth, multi-factor and long-term studies on diverse species are needed.

  6. Ultralow field emission from thinned, open-ended, and defected carbon nanotubes by using microwave hydrogen plasma processing

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Jian-Hua, E-mail: jhdeng1983@163.com [College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Cheng, Lin; Wang, Fan-Jie; Yu, Bin; Li, Guo-Zheng; Li, De-Jun [College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Cheng, Guo-An [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China)

    2015-01-01

    Graphical abstract: Thinned, open-ended, and defected carbon nanotubes were prepared by using hydrogen plasma processing. The processed carbon nanotubes have far better field emission performance than that of the pristine ones. - Highlights: • CVD prepared CNT arrays were processed by microwave hydrogen plasma. • Thinned, open-ended, and defected CNTs were obtained. • Processed CNTs have far better field emission performance than the pristine ones. • Processed CNTs have applicable emission stability after being perfectly aged. - Abstract: Ultralow field emission is achieved from carbon nanotubes (CNTs) by using microwave hydrogen plasma processing. After the processing, typical capped CNT tips are removed, with thinned, open-ended, and defected CNTs left. Structural analyses indicate that the processed CNTs have more SP{sup 3}-hybridized defects as compared to the pristine ones. The morphology of CNTs can be readily controlled by adjusting microwave powers, which change the shape of CNTs by means of hydrogen plasma etching. Processed CNTs with optimal morphology are found to have an ultralow turn-on field of 0.566 V/μm and threshold field of 0.896 V/μm, much better than 0.948 and 1.559 V/μm of the as-grown CNTs, respectively. This improved FE performance is ascribed to the structural changes of CNTs after the processing. The thinned and open-ended shape of CNTs can facilitate electron tunneling through barriers and additionally, the increased defects at tube walls can serve as new active emission sites. Furthermore, our plasma processed CNTs exhibit excellent field emission stability at a large emission current density of 10.36 mA/cm{sup 2} after being perfectly aged, showing promising prospects in applications as high-performance vacuum electron sources.

  7. Effects of breeding habitat and field margins on the reproductive performance of Skylarks (Alauda arvensis) on intensive farmland

    NARCIS (Netherlands)

    Kuiper, M.W.; Ottens, H.J.; Ruijven, van J.; Koks, B.J.; Snoo, de G.R.; Berendse, F.

    2015-01-01

    Field margin management is a common measure employed in Europe to support farmland bird populations. In this study we found and analysed 237 nests of the Skylark Alauda arvensis in the Netherlands over a period of 6 years to determine the effects of arable field margins and breeding crop on nest-lev

  8. Cold-seep habitat mapping: high-resolution spatial characterization of the Blake Ridge Diapir seep field

    Science.gov (United States)

    Wagner, Jamie K.S.; McEntee, Molly H.; Brothers, Laura L.; German, Christopher R.; Kaiser, Carl L.; Yoerger, Dana R.; Van Dover, Cindy Lee

    2013-01-01

    Relationships among seep community biomass, diversity, and physiographic controls such as underlying geology are not well understood. Previous efforts to constrain these relationships at the Blake Ridge Diapir were limited to observations from piloted deep-submergence vehicles. In August 2012, the autonomous underwater vehicle (AUV) Sentry collected geophysical and photographic data over a 0.131 km2 area at the Blake Ridge Diapir seeps. A nested survey approach was used that began with a regional or reconnaissance-style survey using sub-bottom mapping systems to locate and identify seeps and underlying conduits. This survey was followed by AUV-mounted sidescan sonar and multibeam echosounder systems mapping on a mesoscale to characterize the seabed physiography. At the most detailed survey level, digital photographic imaging was used to resolve sub-meter characteristics of the biology. Four pockmarks (25–70 m diameter) were documented, each supporting chemosynthetic communities. Concentric zonation of mussels and clams suggests the influence of chemical gradients on megafaunal distribution. Data collection and analytical techniques used here yield high-resolution habitat maps that can serve as baselines to constrain temporal evolution of seafloor seeps, and to inform ecological niche modeling and resource management.

  9. Open and Closed String Vertices for branes with magnetic field and T-duality

    CERN Document Server

    Pesando, I

    2009-01-01

    We discuss carefully the vertices which describe the dipole open strings and closed strings on a D-brane with magnetic flux on a torus. Translation invariance along closed cycles forces surprisingly closed string vertices written in open string formalism to acquire Chan-Paton like matrices. Moreover the one loop amplitudes have a single trace for the part of gauge group with the magnetic flux. These peculiarities are also required by consistency of the action of T-duality in the open string sector. In this way we can show to all orders in perturbation theory the equivalence of the T-dual open string theories, gravitational interactions included. We provide also a new and direct derivation of the bosonic boundary state in presence of constant magnetic and Kalb-Ramond background based on Sciuto-Della Selva-Saito vertex formalism.

  10. Open and closed string vertices for branes with magnetic field and T-duality

    Science.gov (United States)

    Pesando, Igor

    2010-02-01

    We discuss carefully the vertices which describe the dipole open strings and closed strings on a D-brane with magnetic flux on a torus. Translation invariance along closed cycles forces surprisingly closed string vertices written in open string formalism to acquire Chan-Paton like matrices. Moreover the one loop amplitudes have a single trace for the part of gauge group with the magnetic flux. These peculiarities are also required by consistency of the action of T-duality in the open string sector. In this way we can show to all orders in perturbation theory the equivalence of the T-dual open string theories, gravitational interactions included. We provide also a new and direct derivation of the bosonic boundary state in presence of constant magnetic and Kalb-Ramond background based on Sciuto-Della Selva-Saito vertex formalism.

  11. Species-specific photosynthetic responses of four coniferous seedlings to open-field experimental warming

    Science.gov (United States)

    Han, S.; Yoon, S. J.; Yoon, T. K.; Han, S. H.; Lee, J.; Lee, D.; Kim, S.; Hwang, J.; Cho, M.; Son, Y.

    2014-12-01

    Temperature increase under climate change is expected to affect photosynthesis of tree species. Biochemical models generally suggest that the elevated temperature increases the photosynthetic carbon fixation, however, many opposing results were reported as well. We aimed to examine the photosynthetic responses of four coniferous seedlings to projected future temperature increase, by conducting an open-field warming experiment. Experimental warming set-up using infra-red heater was built in 2011 and the temperature in warming plots has been regulated to be consistently 3oC higher than that of control plots. The seeds of Abies holophylla (AH), A. koreana (AK), Pinus densiflora (PD), and P. koraiensis (PK) were planted in each 1 m × 1 m plot (n=3) in April, 2012. Monthly net photosynthetic rates (Pn; μmol CO2 m-2 s-1) of 1-year-old seedlings (n=9) from June to November, 2013 were measured using CIRAS-2 (PP-Systems, UK) and photosynthetic parameters (the apparent quantum yield; ф; µmol CO2 mol-1, the dark respiration rate; Rd; µmol CO2 mol-1, and the light compensation point; LCP; µmol mol-1 s-1) were also calculated from the light-response curve of photosynthesis in August, 2013. Chlorophyll contents were measured using DMSO extraction method. Monthly Pn was generally higher for PD and decreased for AK in warmed plots than in control plots (Fig. 1). Pn of AK and PK did not show any significant difference, however, Pn of PK in October and November increased by experimental warming. Pn of PD also showed the highest increase in November and this distinct increase of Pn in autumn might be caused by delayed cessation of photosynthesis by temperature elevation. ф and Rd in warmed plots were higher for PD and lower for AK, while LCP did not significantly differ by treatments for all species. Because ф is considered to be related to the efficiency of harvesting and using light, the change in ф might have caused the response of Pn to warming in this study. Decreases

  12. Transfer-matrix simulations of field emission from bundles of open and closed (5,5) carbon nanotubes

    Science.gov (United States)

    Mayer, A.; Miskovsky, N. M.; Cutler, P. H.; Lambin, Ph.

    2003-12-01

    We present simulations of field emission from bundles of metallic (5,5) carbon nanotubes, which are either ideally open or closed. The scattering calculations are achieved using a transfer-matrix methodology for consideration of three-dimensional aspects of both the emitting structure and the surface barrier. Band-structure effects are reproduced by using pseudopotentials and enforcing the incident states to first travel through a periodic repetition of the tubes’ basic cell before entering the region containing the fields. The bundles consist of three and six identical structures, which are placed at the corners of equilateral triangles. In all cases, the closed emitters are found to emit less current than the open ones and to be more sensitive to the electric field in their response to neighboring tubes. Due to the enhanced screening of the electric field, the bundles’ emission rates are reduced compared to those of the isolated tubes. It turns out that the rates characterizing bundle and isolated emitters are related by a simple formula, whose dependence on the electric field suggests deviations from the Fowler-Nordheim equation at high fields. Finally, the position of peaks associated with quasilocalized states on top of the closed emitters appears to be a strong indicator of the tubes’ environment.

  13. Free and Open Source Software for Geospatial in the field of planetary science

    Science.gov (United States)

    Frigeri, A.

    2012-12-01

    Information technology applied to geospatial analyses has spread quickly in the last ten years. The availability of OpenData and data from collaborative mapping projects increased the interest on tools, procedures and methods to handle spatially-related information. Free Open Source Software projects devoted to geospatial data handling are gaining a good success as the use of interoperable formats and protocols allow the user to choose what pipeline of tools and libraries is needed to solve a particular task, adapting the software scene to his specific problem. In particular, the Free Open Source model of development mimics the scientific method very well, and researchers should be naturally encouraged to take part to the development process of these software projects, as this represent a very agile way to interact among several institutions. When it comes to planetary sciences, geospatial Free Open Source Software is gaining a key role in projects that commonly involve different subjects in an international scenario. Very popular software suites for processing scientific mission data (for example, ISIS) and for navigation/planning (SPICE) are being distributed along with the source code and the interaction between user and developer is often very strict, creating a continuum between these two figures. A very widely spread library for handling geospatial data (GDAL) has started to support planetary data from the Planetary Data System, and recent contributions enabled the support to other popular data formats used in planetary science, as the Vicar one. The use of Geographic Information System in planetary science is now diffused, and Free Open Source GIS, open GIS formats and network protocols allow to extend existing tools and methods developed to solve Earth based problems, also to the case of the study of solar system bodies. A day in the working life of a researcher using Free Open Source Software for geospatial will be presented, as well as benefits and

  14. Effects of rat sex differences and lighting on locomotor exploration of a circular open field with free-standing central corners and without peripheral walls.

    Science.gov (United States)

    Alstott, Jeff; Timberlake, William

    2009-01-23

    A typical open field consists of a square enclosure, bounded by four straight walls joined by identical corners. For decades behavioral researchers have used the open center and more sheltered perimeter of such fields to examine the effects of drugs, sex differences, and illumination on the behavioral expression of fear and anxiety. The present study "reversed" the relative security of the center and periphery of a circular field to re-examine the functional relation of open field behavior to experience, sex differences and lighting. Across six daily exposures, males in both the light and dark rapidly increased their preference for the center. Females in the light developed a similar pattern, though more slowly; females in the dark continued to spend the great majority of their time in the open periphery, including the edge of the field. The behavior of all groups, but especially the dark females, strongly supports the continued importance of environmental assessment in open field behavior.

  15. Habitat Suitability Index Models: Red king crab

    Science.gov (United States)

    Jewett, Stephen C.; Onuf, Christopher P.

    1988-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for evaluating habitat of different life stages of red king crab (Paralithodes camtschatica). A model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) and 1.0 (optimum habitat) in Alaskan coastal waters, especially in the Gulf of Alaska and the southeastern Bering Sea. HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  16. Involvement of regions of the 4th and 7th chromosomes in the open-field activity of mice.

    Science.gov (United States)

    Clément, Y; Martin, B; Venault, P; Chapouthier, G

    1995-09-01

    Reactivity to a new environment was studied in mice, using an open-field procedure in two strains, C57BL/6By and ABP/Le, the F1 populations and the intercrosses F2 and backcross segregating populations. The analysis of the behavioral traits: peripheral and central activities, leaning, rearing and defecation in the parental strains made it possible to show that the ABP/Le strain was more reactive than C57BL/6By. In addition, the study of segregating, for four phenotypic markers, in F2 and backcross populations strongly suggested that two autosomal regions were involved in the control of open-field behavior: one in chromosomal region comprising the b locus on chromosome 4 and one in chromosomal region comprising the p locus on chromosome 7.

  17. Airborne Open Polar/Imaging Nephelometer for Ice Particles in Cirrus Clouds and Aerosols Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Martins, JV [Univ. of Maryland, College Park, MD (United States)

    2016-04-01

    The Open Imaging Nephelometer (O-I-Neph) instrument is an adaptation of a proven laboratory instrument built and tested at the University of Maryland, Baltimore County (UMBC), the Polarized Imaging Nephelometer (PI-Neph). The instrument design of both imaging nephelometers uses a narrow-beam laser source and a wide-field-of-view imaging camera to capture the entire scattering-phase function in one image, quasi-instantaneously.

  18. Clinical effects of buprenorphine on open field behaviour and gait symmetry in healthy and lame weaned piglets.

    Science.gov (United States)

    Meijer, Ellen; van Nes, Arie; Back, Willem; van der Staay, Franz Josef

    2015-12-01

    Lameness in pigs decreases animal welfare and economic profit for the farmer. An important reason for impaired welfare in lame animals is pain due to lameness. No direct measurement of pain is possible in animals, and methods to indirectly detect and quantify the amount of pain an animal is experiencing are urgently needed. In this study, two methods to assess pain associated with lameness in pigs were evaluated to determine if they were sensitive enough to detect a lameness reduction as an effect of an experimental analgesic medication. Asymmetry associated with lameness was objectively quantified using pressure mat kinetic parameters: peak vertical force (PVF), load rate (LR), vertical impulse (VI) and peak vertical pressure (PVP). Locomotor activity was assessed in an open field test. A dose of 0.04 mg/kg buprenorphine, a strong analgesic, was used to treat 10 lame pigs, while eight other lame pigs, treated with physiological saline solution, served as controls. Buprenorphine decreased lameness-associated asymmetry for pressure mat LR (P = 0.002), VI (P = 0.003) and PVP (P = 0.001) and increased activity of the lame pigs in the open field (P = 0.023), while saline-treated animals did not show any changes in asymmetry and became less active in the open field (P open field test are both sensitive enough to detect the analgesic effects of buprenorphine when used to treat moderate to severe clinical pain in a relatively small group of affected pigs. The methods used in this study may also provide promising additional tools for future research into early pain recognition and lameness treatment in pigs.

  19. Capture of non-target flies (Diptera: Lauxaniidae, Chloropidae, Anthomyiidae) on traps baited with volatile chemicals in field crop habitats

    Science.gov (United States)

    Volatile chemicals increased trap catch of flies from the families Lauxaniidae [Homoneura bispina (Loew) and Camptoprosopella borealis Shewell], Chloropidae (Olcella sp.) and Anthomyiidae (Delia spp.) in field crops. With cotton rolls as dispensers, baiting with 2-phenylethanol increased catch of H...

  20. Searching for links between magnetic fields and stellar evolution. I. A survey of magnetic fields in open cluster A- and B-type stars with FORS1

    CERN Document Server

    Bagnulo, S; Landstreet, J D; Mason, E; Silaj, J; Wade, G A

    2006-01-01

    About 5% of upper main sequence stars are permeated by a strong magnetic field, the origin of which is still matter of debate. With this work we provide observational material to study how magnetic fields change with the evolution of stars on the main sequence, and to constrain theory explaining the presence of magnetic fields in A and B-type stars. Using FORS1 in spectropolarimetric mode at the ESO VLT, we have carried out a survey of magnetic fields in early-type stars belonging to open clusters and associations of various ages. We have measured the magnetic field of 235 early-type stars with a typical uncertainty of about 100 G. In our sample, 97 stars are Ap or Bp stars. For these targets, the median error bar of our field measurements was about 80 G. A field has been detected in about 41 of these stars, 37 of which were not previously known as magnetic stars. For the 138 normal A and B-type stars, the median error bar was 136 G, and no field was detected in any of them.

  1. A target field design of open multi-purpose RF coil for musculoskeletal MR imaging at 3T.

    Science.gov (United States)

    Gao, Fei; Zhang, Rui; Zhou, Diange; Wang, Xiaoying; Huang, Kefu; Zhang, Jue

    2016-10-01

    Musculoskeletal MR imaging under multi-angle situations plays an increasingly important role in assessing joint and muscle tissues system. However, there are still limitations due to the closed structures of most conventional RF coils. In this study, a time-harmonic target-field method was employed to design open multi-purpose coil (OMC) for multi-angle musculoskeletal MR imaging. The phantom imaging results suggested that the proposed OMC could achieve homogeneously distributed magnetic field and high signal-to-noise ratio (SNR) of 239.04±0.83 in the region of interest (ROI). The maximum temperature in the heating hazard test was 16°C lower than the standard regulation, which indicated the security of the designed OMC. Furthermore, to demonstrate the effectiveness of the proposed OMC for musculoskeletal MR imaging, especially for multi-angle imaging, a healthy volunteer was examined for MR imaging of elbow, ankle and knee using OMC. The in vivo imaging results showed that the proposed OMC is effective for MR imaging of musculoskeletal tissues at different body parts, with satisfied B1 field homogeneity and SNR. Moreover, the open structure of the OMC could provide a large joint movement region. The proposed open multi-purpose coil is feasible for musculoskeletal MR imaging, and potentially, it is more suitable for the evaluation of musculoskeletal tissues under multi-angle conditions. Copyright © 2016. Published by Elsevier Inc.

  2. Open-field host specificity test of Gratiana boliviana (Coleoptera:Chrysomelidae), a biological control agent of Tropical Soda Apple (Solanaceae) in the United States

    Science.gov (United States)

    An open-field experiment was conducted to asses the suitability of the South American leaf feeding beetle Gratiana boliviana Spaeth for biological control of Solanum viarum Dunal in the USA. An open-field test with eggplant, Solanum melongena L., was conducted on the campus of the University of Buen...

  3. IMPAIRED LEARNING AND ABNORMAL OPEN-FIELD BEHAVIORS OF RATS AFTER EARLY POSTNATAL ANOXIA AND THE BENEFICIAL EFFECT OF THE CALCIUM-ANTAGONIST NIMODIPINE

    NARCIS (Netherlands)

    NYAKAS, C; MARKEL, E; SCHUURMAN, T; LUITEN, PGM

    1991-01-01

    Perinatal anoxia/hypoxia is considered a serious risk factor for normal brain development. Anoxia induced by repeated asphyxia at 2 and 4 days after birth resulted in a transient hyperactivity in the small open-field, and a behavioural depression in adult open-field activity of male Wistar rats. The

  4. A detailed ethological analysis of the mouse open field test: effects of diazepam, chlordiazepoxide and an extremely low frequency pulsed magnetic field.

    Science.gov (United States)

    Choleris, E; Thomas, A W; Kavaliers, M; Prato, F S

    2001-05-01

    The open field test (OFT) is a widely used procedure for examining the behavioral effects of drugs and anxiety. Detailed ethological assessments of animal behavior are lacking. Here we present a detailed ethological assessment of the effects of acute treatment with the benzodiazepines, diazepam (DZ, 1.5mg/kg) and chlordiazepoxide (CDP, 5.0 and 10.0mg/kg), as well as exposure to a non-pharmacological agent, a specific pulsed extremely low frequency magnetic field (MAG) on open field behavior. We examined the duration, frequency and time course of various behaviors (i.e. exploration, walk, rear, stretch attend, return, groom, sit, spin turn, jump and sleep) exhibited by male mice in different regions of a novel open field. Both DZ and CDP consistently reduced the typical anxiety-like behaviors of stretch attend and wall-following (thigmotaxis), along with that of an additional new measure: 'returns', without producing any overall effects on total locomotion. The drugs also differed in their effects. CDP elicited a shift in the locomotor pattern from a 'high explore' to a 'high walk', while DZ mainly elicited alterations in sit and groom. The MAG treatment was repeated twice with both exposures reducing horizontal and vertical (rearing) activity and increasing grooming and spin turns. However, the anxiety-like behaviors of stretch attend and return were marginally reduced by only the first exposure. We conclude that a detailed ethological analysis of the OFT allows not only the detection of specific effects of drugs and non-pharmacological agents (i.e. pulsed magnetic field) on anxiety-like behaviors, but also permits the examination of non-specific effects, in particular those on general activity.

  5. Priority Fields of Teachers’ Professional Development in Terms of Open Education Worldwide

    Directory of Open Access Journals (Sweden)

    Avshenyuk Nataliya

    2016-12-01

    Full Text Available The article is devoted to the problem of teachers’ professional development within the concept of “open educational resources”. The author analyzes the project “Massive Open Online Courses” (MOOC as one of the modern achievements in the area of information and communication technology (ICT for the development of adult education, namely teachers’ professional development in the context of globalization. It has been determined that MOOC is an innovative form of free distance learning, which is represented by full-fledged interactive training courses based on open access to the Internet for the simultaneous participation of a large number of people. Conceptual bases of creation and functioning MOOC, which are based on two key principles of the theory of learning organization - Cognitive behaviorism and Connectivism have been characterized. It has been found out that most of the discussions developed around the main implementation problems of MOOC are: the presence of two different types of MOOC; the role of the teacher in MOOC; participation of students in MOOC; understanding and use of “mass” in MOOC; tracking the border between openness of MOOC and control over their quality. The analysis of the contemporary MOOC platforms shows that the most popular pedagogical-oriented courses are: the development of students’ thinking; e-learning and digital culture; schools: history of school education, educational policy; how to become a developer of blended learning technologies as well as development of educational technologies.

  6. Attracted to open access journals: A bibliometric author analysis in the field of biology

    DEFF Research Database (Denmark)

    Faber Frandsen, Tove

    2009-01-01

    countries and is thus a supplement to the existing author surveys and interviews. Design/methodology/approach - Bibliometric analyses of both publishing behaviour and citing behaviour in relation to OA publishing provides evidence of the impact of open access on developing countries. Findings - The results...

  7. The integration of open access journals in the scholarly communication system: Three science fields

    DEFF Research Database (Denmark)

    Faber Frandsen, Tove

    2009-01-01

    The greatest number of open access journals (OAJs) is found in the sciences and their influence is growing. However, there are only a few studies on the acceptance and thereby integration of these OAJs in the scholarly communication system. Even fewer studies provide insight into the differences...

  8. Attracted to open access journals: A bibliometric author analysis in the field of biology

    DEFF Research Database (Denmark)

    Faber Frandsen, Tove

    2009-01-01

    countries and is thus a supplement to the existing author surveys and interviews. Design/methodology/approach - Bibliometric analyses of both publishing behaviour and citing behaviour in relation to OA publishing provides evidence of the impact of open access on developing countries. Findings - The results...

  9. Differential phase contrast 2.0-Opening new 'fields' for an established technique

    Energy Technology Data Exchange (ETDEWEB)

    Lohr, Matthias; Schregle, Ralph [Physics Faculty, Regensburg University, Universitaetsstrasse 31, D-93040 Regensburg (Germany); Jetter, Michael; Waechter, Clemens [Institute for Semiconductor Optics and Functional Interfaces, Stuttgart University, Pfaffenwaldring 57, D-70569 Stuttgart (Germany); Wunderer, Thomas; Scholz, Ferdinand [Institute for Optoelectronics, Ulm University, Albert-Einstein-Allee 45, D-89081 Ulm (Germany); Zweck, Josef, E-mail: josef.zweck@physik.uni-regensburg.de [Physics Faculty, Regensburg University, Universitaetsstrasse 31, D-93040 Regensburg (Germany)

    2012-06-15

    Differential phase contrast microscopy has become known as a high resolution imaging technique for magnetic micro-structures in the past. The method senses the local induction by measuring the deflection of the probe beam after it passes through a specimen area carrying a magnetic field. Little attention has been paid, however, to the fact that this technique is also capable of measuring electric fields. An application of the technique to measure piezoelectric polarization fields inside multi-layered structures such as quantum wells is demonstrated. For this purpose, piezoelectric fields within non-centrosymmetric crystal structures, based on GaN/InGaN/GaN quantum wells, are investigated. It can be shown that the technique is sensitive to these fields and yields detailed information about the field distribution. The specific information and experimental limitations as well as artefacts of the technique will be discussed in detail and first measurements are shown. The main advantages turn out to be high sensitivity for electric fields, combined with a very high resolution, which is limited only by the STEM probe size. Another advantage is the large achievable field of view. -- Highlights: Black-Right-Pointing-Pointer We describe a technique which allows the determination of inner electric fields in matter. Black-Right-Pointing-Pointer Inner fields are believed to be one major reason for the so-called efficiency 'droop' in green solid state lasers. Black-Right-Pointing-Pointer The technique used is differential phase contrast, used for the first time for inner electric field determination. Black-Right-Pointing-Pointer The technique is complementary to electron holography, offers a wider field of view and reveals new structures.

  10. The biology of habitat dominance; can microbes behave as weeds?

    Science.gov (United States)

    Cray, Jonathan A; Bell, Andrew N W; Bhaganna, Prashanth; Mswaka, Allen Y; Timson, David J; Hallsworth, John E

    2013-09-01

    , such as Escherichia coli, Mycobacterium smegmatis and Pseudoxylaria spp., exhibit characteristics of both weed and non-weed species. We propose that the concept of nonweeds represents a 'dustbin' group that includes species such as Synodropsis spp., Polypaecilum pisce, Metschnikowia orientalis, Salmonella spp., and Caulobacter crescentus. We show that microbial weeds are conceptually distinct from plant weeds, microbial copiotrophs, r-strategists, and other ecophysiological groups of microorganism. Microbial weed species are unlikely to emerge from stationary-phase or other types of closed communities; it is open habitats that select for weed phenotypes. Specific characteristics that are common to diverse types of open habitat are identified, and implications of weed biology and open-habitat ecology are discussed in the context of further studies needed in the fields of environmental and applied microbiology. © 2013 The Authors. Microbial Biotechnology Published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  11. Ultralow field emission from thinned, open-ended, and defected carbon nanotubes by using microwave hydrogen plasma processing

    Science.gov (United States)

    Deng, Jian-Hua; Cheng, Lin; Wang, Fan-Jie; Yu, Bin; Li, Guo-Zheng; Li, De-Jun; Cheng, Guo-An

    2015-01-01

    Ultralow field emission is achieved from carbon nanotubes (CNTs) by using microwave hydrogen plasma processing. After the processing, typical capped CNT tips are removed, with thinned, open-ended, and defected CNTs left. Structural analyses indicate that the processed CNTs have more SP3-hybridized defects as compared to the pristine ones. The morphology of CNTs can be readily controlled by adjusting microwave powers, which change the shape of CNTs by means of hydrogen plasma etching. Processed CNTs with optimal morphology are found to have an ultralow turn-on field of 0.566 V/μm and threshold field of 0.896 V/μm, much better than 0.948 and 1.559 V/μm of the as-grown CNTs, respectively. This improved FE performance is ascribed to the structural changes of CNTs after the processing. The thinned and open-ended shape of CNTs can facilitate electron tunneling through barriers and additionally, the increased defects at tube walls can serve as new active emission sites. Furthermore, our plasma processed CNTs exhibit excellent field emission stability at a large emission current density of 10.36 mA/cm2 after being perfectly aged, showing promising prospects in applications as high-performance vacuum electron sources.

  12. A New Analysis in the Field of the Open Cluster Collinder 223

    Institute of Scientific and Technical Information of China (English)

    A. L. Tadross

    2004-01-01

    The present study of the open cluster Collinder 223 (Cr 223) depended greatly on the photoelectric data of Claria and Lapasset. We use the data in conjunction with the AAO/DSS1 image of the cluster in a re-investigation to improve the main parameters of Cr 223, including the stellar density, the position of the cluster's center, the cluster's diameter. Its luminosity function, mass function, and total mass are also estimated.

  13. MONITORING OF IN-FIELD VARIABILITY FOR SITE SPECIFIC CROP MANAGEMENT THROUGH OPEN GEOSPATIAL INFORMATION

    Directory of Open Access Journals (Sweden)

    T. Řezník

    2016-06-01

    Full Text Available The agricultural sector is in a unique position due to its strategic importance around the world. It is crucial for both citizens (consumers and the economy (both regional and global, which, ideally, should ensure that the whole sector is a network of interacting organisations. It is important to develop new tools, management methods, and applications to improve the management and logistic operations of agricultural producers (farms and agricultural service providers. From a geospatial perspective, this involves identifying cost optimization pathways, reducing transport, reducing environmental loads, and improving the energy balance, while maintaining production levels, etc. This paper describes the benefits of, and open issues arising from, the development of the Open Farm Management Information System. Emphasis is placed on descriptions of available remote sensing and other geospatial data, and their harmonization, processing, and presentation to users. At the same time, the FOODIE platform also offers a novel approach of yield potential estimations. Validation for one farm demonstrated 70% successful rate when comparing yield results at a farm counting 1’284 hectares on one hand and results of a theoretical model of yield potential on the other hand. The presented Open Farm Management Information System has already been successfully registered under Phase 8 of the Global Earth Observation System of Systems (GEOSS Architecture Implementation Pilot in order to support the wide variety of demands that are primarily aimed at agriculture and water pollution monitoring by means of remote sensing.

  14. Monitoring of In-Field Variability for Site Specific Crop Management Through Open Geospatial Information

    Science.gov (United States)

    Řezník, T.; Lukas, V.; Charvát, K.; Charvát, K., Jr.; Horáková, Š.; Křivánek, Z.; Herman, L.

    2016-06-01

    The agricultural sector is in a unique position due to its strategic importance around the world. It is crucial for both citizens (consumers) and the economy (both regional and global), which, ideally, should ensure that the whole sector is a network of interacting organisations. It is important to develop new tools, management methods, and applications to improve the management and logistic operations of agricultural producers (farms) and agricultural service providers. From a geospatial perspective, this involves identifying cost optimization pathways, reducing transport, reducing environmental loads, and improving the energy balance, while maintaining production levels, etc. This paper describes the benefits of, and open issues arising from, the development of the Open Farm Management Information System. Emphasis is placed on descriptions of available remote sensing and other geospatial data, and their harmonization, processing, and presentation to users. At the same time, the FOODIE platform also offers a novel approach of yield potential estimations. Validation for one farm demonstrated 70% successful rate when comparing yield results at a farm counting 1'284 hectares on one hand and results of a theoretical model of yield potential on the other hand. The presented Open Farm Management Information System has already been successfully registered under Phase 8 of the Global Earth Observation System of Systems (GEOSS) Architecture Implementation Pilot in order to support the wide variety of demands that are primarily aimed at agriculture and water pollution monitoring by means of remote sensing.

  15. Ontogeny and adolescent alcohol exposure in Wistar rats: open field conflict, light/dark box and forced swim test.

    Science.gov (United States)

    Desikan, Anita; Wills, Derek N; Ehlers, Cindy L

    2014-07-01

    Epidemiological studies have demonstrated that heavy drinking and alcohol abuse and dependence peak during the transition between late adolescence and early adulthood. Studies in animal models have demonstrated that alcohol exposure during adolescence can cause a modification in some aspects of behavioral development, causing the "adolescent phenotype" to be retained into adulthood. However, the "adolescent phenotype" has not been studied for a number of behavioral tests. The objective of the present study was to investigate the ontogeny of behaviors over adolescence/young adulthood in the light/dark box, open field conflict and forced swim test in male Wistar rats. These data were compared to previously published data from rats that received intermittent alcohol vapor exposure during adolescence (AIE) to test whether they retained the "adolescent phenotype" in these behavioral tests. Three age groups of rats were tested (post-natal day (PD) 34-42; PD55-63; PD69-77). In the light/dark box test, younger rats escaped the light box faster than older adults, whereas AIE rats returned to the light box faster and exhibited more rears in the light than controls. In the open field conflict test, both younger and AIE rats had shorter times to first enter the center, spent more time in the center of the field, were closer to the food, and consumed more food than controls. In the forced swim test no clear developmental pattern emerged. The results of the light/dark box and the forced swim test do not support the hypothesis that adolescent ethanol vapor exposure can "lock-in" all adolescent phenotypes. However, data from the open field conflict test suggest that the adolescent and the AIE rats both engaged in more "disinhibited" and food motivated behaviors. These data suggest that, in some behavioral tests, AIE may result in a similar form of behavioral disinhibition to what is seen in adolescence.

  16. 3DFD Simulation of Asymmetric Wave Field by Side-wall Acoustic Tool in Open and Cased Wells

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    We developed a parallelized scheme of 3D finite difference (3DFD) with non-uniform staggered grid to simulate the eccentric borehole acoustic field with side-wall acoustic logging tools in open and cased wells. Higher accuracy and lower computation cost were achieved with this scheme for modeling such an asymmetric wave field generated by a high frequency source near or on the borehole wall. We also modeled the cases with and without considering the effects of the tool body. The simulation results demonstrated that the logging tool body would attenuate the direct waves but have only little influence on the interface waves in such a borehole condition. The effects of the tool body on the wave field were significant only when the contrast of the elastic properties between tool body and borehole fluid was large.

  17. Open-System Quantum Annealing in Mean-Field Models with Exponential Degeneracy

    Science.gov (United States)

    2016-08-25

    Research Center, Mail Stop 269-3, Moffett Field, California 94035 USRA, NASA Ames Research Center, Moffett Field, California 94035, USA 2Google, 150 Main...principle, be reproduced using an analog quantum annealer. Before outlining the formal calculation, we discuss the qualitative picture of the effect of...performance (computation time) of SA and QA is charac- terized by the numerical scaling factors in the exponent (in front ofN),whichhave tobecarefully

  18. Microhabitat use by white-footed mice Peromyscus leucopus in forested and old-field habitats occupied by Morrow's honeysuckle Lonicera morrowii

    Institute of Scientific and Technical Information of China (English)

    Jennifer A.EDALGO; Holly M.McCHESNEY; Jason P.LOVE; James T.ANDERSON

    2009-01-01

    We quantified microhabitat use by white-footed mice Peromyscus leucopus in forest and old-field habitats occupied by Morrow's honeysuckle Lonicera morrowii, an invasive exotic shrub imported from Japan. Microhabitat characteristics were compared between trails used by mice (n=124) and randomly selected trails (n=127) in 4 study plots located at Fort Necessity National Battlefield, Farmington, Pennsylvania, USA. We compared 10 microhabitat variables between used and random trails using non-metric multidimensional scaling (NMDS) and classification and regression tree (CART) analysis. Trails used by mice were statistically different from randomly selected trails in both forested plots (P<0.008) and old-field plots (P<0.001). In the forested plots, trails of white-footed mice were more often associated with a greater percent cover (% cover) of coarse woody debris (CWD) than were randomly selected trails. In the old-field plots, mouse trails were commonly characterized by having a lower % cover of exotic herbaceous vegetation, a greater % cover of shrubs, and a greater % cover of Morrow's honeysuckle than randomly selected trails. Our study indicates that white-footed mice do not move randomly and prefer areas of high structural complexity, thereby showing significant microhabitat preference. The preference of white-footed mice for areas with a relatively high percent cover of Morrow's honeysuckle could 1) be a factor in the aggressive nature of the exotic honeysuckle shrub's spread throughout the Battlefield or 2) cause the shrub to spread even faster into adjacent areas not yet occupied by Morrow's honeysuckle[Current Zoology 55(2):111-122,2009].

  19. Carbon-Carbon Bond Formation in a Weak Ligand Field: Leveraging Open Shell First Row Transition Metal Catalysts.

    Science.gov (United States)

    Chirik, Paul James

    2017-01-12

    Unique features of Earth abundant transition metal catalysts are reviewed in the context of catalytic carbon-carbon bond forming reactions. Aryl-substituted bis(imino)pyridine iron and cobalt dihalide compounds, when activated with alkyl aluminum reagents, form highly active catalysts for the polymerization of ethylene. Open shell iron and cobalt alkyl complexes have been synthesized that serve as single component olefin polymerization catalysts. Reduced bis(imino)pyridine iron- and cobalt dinitrogen compounds have also been discovered that promote the unique [2+2] cycloaddition of unactivated terminal alkenes. Electronic structure studies support open shell intermediates, a deviation from traditional strong field organometallic compounds that promote catalytic C-C bond formation.

  20. Field measurements of aerosol production from whitecaps in the open ocean

    Directory of Open Access Journals (Sweden)

    S. J. Norris

    2012-10-01

    Full Text Available Simultaneous measurements of near-surface aerosol and bubble spectra were made during five buoy deployments in the open ocean of the North Atlantic and used to estimate aerosol fluxes per unit area of whitecap. The measurements were made during two cruises as part of the SEASAW project, a UK contribution to the international SOLAS program. The mean bubble number concentrations for each deployment are in broad agreement with other open ocean spectra and are consistently one to two orders of magnitude lower than previous laboratory and surf zone studies. This suggests that the aerosol fluxes estimated above open ocean whitecaps will differ to those from over the surf zone and laboratory whitecaps due to the differences in the size and number of bursting bubbles. Production fluxes per unit area of whitecap are estimated from the mean aerosol concentration for each buoy deployment. They are found to increase with wind speed, and span the range of values found by previous laboratory and surf-zone studies for particles with radius at 80% humidity, R80 < 1 μm, but to drop off more rapidly with increasing size for larger particles. A possible cause of this difference in behavior is the significant difference in bubble spectra. Estimates of the mean sea spray flux were made by scaling the whitecap production fluxes with in-situ estimates of whitecap fraction. The sea spray fluxes are also compared with simultaneous individual eddy covariance flux estimates made during the cruise, and with a sea spray source function derived from them.

  1. Heart Rate Variability in Nonlinear Rats with Different Orientation and Exploratory Activity in the Open Field.

    Science.gov (United States)

    Kur'yanova, E V; Teplyi, D L; Zhukova, Yu D; Zhukovina, N V

    2015-12-01

    The basic behavioral activity of nonlinear rats was evaluated from the sum of crossed peripheral and central squares and peripheral and central rearing postures in the open fi eld test. This index was low (30 episodes). Male rats with high score of orientation and exploratory activity were characterized by higher indexes of total heart rate variability than rats with low or intermediate activity. Specimens with a greater contribution of VLF waves into the total power spectrum of heart rate variability were shown to dominate among the rats with high behavioral activity. Our results are consistent with the notions of a suprasegmental nature of VLF waves.

  2. Direct observation of ring-opening dynamics in strong-field ionized selenophene using femtosecond inner-shell absorption spectroscopy

    Science.gov (United States)

    Lackner, Florian; Chatterley, Adam S.; Pemmaraju, C. D.; Closser, Kristina D.; Prendergast, David; Neumark, Daniel M.; Leone, Stephen R.; Gessner, Oliver

    2016-12-01

    Femtosecond extreme ultraviolet transient absorption spectroscopy is used to explore strong-field ionization induced dynamics in selenophene (C4H4Se). The dynamics are monitored in real-time from the viewpoint of the Se atom by recording the temporal evolution of element-specific spectral features near the Se 3d inner-shell absorption edge (˜58 eV). The interpretation of the experimental results is supported by first-principles time-dependent density functional theory calculations. The experiments simultaneously capture the instantaneous population of stable molecular ions, the emergence and decay of excited cation states, and the appearance of atomic fragments. The experiments reveal, in particular, insight into the strong-field induced ring-opening dynamics in the selenophene cation, which are traced by the emergence of non-cyclic molecules as well as the liberation of Se+ ions within an overall time scale of approximately 170 fs. We propose that both products may be associated with dynamics on the same electronic surfaces but with different degrees of vibrational excitation. The time-dependent inner-shell absorption features provide direct evidence for a complex relaxation mechanism that may be approximated by a two-step model, whereby the initially prepared, excited cyclic cation decays within τ1 = 80 ± 30 fs into a transient molecular species, which then gives rise to the emergence of bare Se+ and ring-open cations within an additional τ2 = 80 ± 30 fs. The combined experimental and theoretical results suggest a close relationship between σ* excited cation states and the observed ring-opening reactions. The findings demonstrate that the combination of femtosecond time-resolved core-level spectroscopy with ab initio estimates of spectroscopic signatures provide new insights into complex, ultrafast photochemical reactions such as ring-opening dynamics in organic molecules in real-time and with simultaneous sensitivity for electronic and structural

  3. Influence of forest and rangeland management on anadromous fish habitat in Western North America: rehabilitating and enhancing stream habitat—2. Field applications.

    Science.gov (United States)

    Gordon H. Reeves; Terry D. Roelofs

    1982-01-01

    Current techniques for rehabilitating and enhancing habitat to increase natural production of anadromous salmonids in the Pacific Northwest and Alaska are described. Methods to enhance spawning, rearing, and riparian habitat, and to improve access are reviewed. The information was compiled from published literature, unpublished reports by State and Federal agencies,...

  4. The spectral analysis of motion: An "open field" activity test example

    Directory of Open Access Journals (Sweden)

    Obradović Z.

    2013-01-01

    Full Text Available In this work we have described the new mathematical approach, with spectral analysis of the data to evaluate position and motion in the „„open field““ experiments. The aim of this work is to introduce several new parameters mathematically derived from experimental data by means of spectral analysis, and to quantitatively estimate the quality of the motion. Two original software packages (TRACKER and POSTPROC were used for transforming a video data to a log file, suitable for further computational analysis, and to perform analysis from the log file. As an example, results obtained from the experiments with Wistar rats in the „open field“ test are included. The test group of animals was treated with diazepam. Our results demonstrate that all the calculated parameters, such as movement variability, acceleration and deceleration, were significantly lower in the test group compared to the control group. We believe that the application of parameters obtained by spectral analysis could be of great significance in assessing the locomotion impairment in any kind of motion. [Projekat Ministarstva nauke Republike Srbije, br. III41007 i br. ON174028

  5. A partially open porous media flow with chaotic advection: towards a model of coupled fields.

    Science.gov (United States)

    Metcalfe, Guy; Lester, Daniel; Ord, Alison; Kulkarni, Pandurang; Trefry, Mike; Hobbs, Bruce E; Regenaur-Lieb, Klaus; Morris, Jeffery

    2010-01-13

    In nature, dissipative fluxes of fluid, heat and/or reacting species couple to each other and may also couple to deformation of a surrounding porous matrix. We use the well-known analogy of Hele-Shaw flow to Darcy flow to make a model porous medium with porosity proportional to local cell height. Time- and space-varying fluid injection from multiple source/sink wells lets us create many different kinds of chaotic flows and chemical concentration patterns. Results of an initial time-dependent potential flow model illustrate that this is a partially open flow, in which parts of the material transported by the flow remain in the cell forever and parts pass through with residence time and exit time distributions that have self-similar features in the control parameter space of the stirring. We derive analytically the existence boundary in stirring control parameter space between where isolated fluid regions can and cannot remain forever in the open flow. Experiments confirm the predictions.

  6. Effect of flow field on open channel flow properties using numerical investigation and experimental comparison

    Energy Technology Data Exchange (ETDEWEB)

    Khazaee, I. [Department of Mechanical Engineering, Torbat-e-jam branch, Islamic Azad University, Torbat-e-jam (Iran, Islamic Republic of); Mohammadiun, M. [Department of Mechanical Engineering, Shahrood branch, Islamic Azad University, Shahrood (Iran, Islamic Republic of)

    2012-07-01

    In this paper a complete three-dimensional and two phase CFD model for flow distribution in an open channel investigated. The finite volume method (FVM) with a dynamic Sub grid-scale was carried out for seven cases of different aspect ratios, different inclination angles or slopes and convergence-divergence condition. The volume of fluid (VOF) method was used to allow the free-surface to deform freely with the underlying turbulence. The discharge through open channel flow is often evaluated by velocity-area integration method from the measurement of velocity at discrete locations in the measuring section. The variation of velocity along horizontal and vertical directions is thus very important to decide the location of the sensors. The aspect ratio of the channel, slope of the channel and divergence- convergence of the channel have investigated and the results show that the depth of water at the end of the channel is higher at AR=0.8 against the AR=0.4 and AR=1.2. Also it is clear that by increasing the inclination angle or slope of the channel in case1, case4 and case5 the depth of the water increases. Also it is clear that the outlet mass flow rate is at a minimum value at a range of inclination angle of the channel.

  7. Female mucopolysaccharidosis IIIA mice exhibit hyperactivity and a reduced sense of danger in the open field test.

    Directory of Open Access Journals (Sweden)

    Alex Langford-Smith

    Full Text Available Reliable behavioural tests in animal models of neurodegenerative diseases allow us to study the natural history of disease and evaluate the efficacy of novel therapies. Mucopolysaccharidosis IIIA (MPS IIIA or Sanfilippo A, is a severe, neurodegenerative lysosomal storage disorder caused by a deficiency in the heparan sulphate catabolising enzyme, sulfamidase. Undegraded heparan sulphate accumulates, resulting in lysosomal enlargement and cellular dysfunction. Patients suffer a progressive loss of motor and cognitive function with severe behavioural manifestations and premature death. There is currently no treatment. A spontaneously occurring mouse model of the disease has been described, that has approximately 3% of normal enzyme activity levels. Behavioural phenotyping of the MPS IIIA mouse has been previously reported, but the results are conflicting and variable, even after full backcrossing to the C57BL/6 background. Therefore we have independently backcrossed the MPS IIIA model onto the C57BL/6J background and evaluated the behaviour of male and female MPS IIIA mice at 4, 6 and 8 months of age using the open field test, elevated plus maze, inverted screen and horizontal bar crossing at the same circadian time point. Using a 60 minute open field, we have demonstrated that female MPS IIIA mice are hyperactive, have a longer path length, display rapid exploratory behaviour and spend less time immobile than WT mice. Female MPS IIIA mice also display a reduced sense of danger and spend more time in the centre of the open field. There were no significant differences found between male WT and MPS IIIA mice and no differences in neuromuscular strength were seen with either sex. The altered natural history of behaviour that we observe in the MPS IIIA mouse will allow more accurate evaluation of novel therapeutics for MPS IIIA and potentially other neurodegenerative disorders.

  8. Effects of ethanol in an open field apparatus: modification by U50488H and WIN 44441-3.

    Science.gov (United States)

    Pohorecky, L A; Patel, V; Roberts, P

    1989-02-01

    The effects of U50488H, a kappa agonist, and WIN 44441-3, a kappa antagonist, and their modification of the effects of ethanol, on the behavior of rats in a modified open field apparatus, was examined. Crossover activity was increased by U50488H. Headpoke activity was decreased by WIN 44441-3 and increased by U50488H. Rearing activity was increased by WIN 44441-3 but was not affected by U50488H. The effect of both drugs was dose related, with the largest doses having no effect. Ethanol (0.5 g/kg) stimulated crossover activity while it depressed rearing, headpoke and corner activities; except for crossover activity the 2.0 g/kg dose of ethanol depressed these activities. Pretreatment with WIN 44441-3 (0.5 mg/kg) potentiated the stimulant effect of ethanol on crossover activity and partially reversed the depressant effect of ethanol on rearing and headpoke activities. U50488H potentiated the ethanol-induced depression of headpoke and reversed the depression of corner activity. Pretreatment with U50488H had no effect on ethanol's action on crossover and rearing behaviors. Our results indicate that kappa opiate receptors may mediate some behaviors exhibited by rats in a modified open field apparatus. Activation of these receptors increases locomotor and headpoke activity but had no effect on rearing activity. Furthermore, the 0.5 g/kg dose of ethanol has differential effects on different measures of open field behavior, while the 2.0 g/kg dose was largely depressant. Our data suggest that some of these effects of ethanol may be mediated via kappa opioid receptors.

  9. Seedling Emergence and Phenotypic Response of Common Bean Germplasm to Different Temperatures under Controlled Conditions and in Open Field

    Directory of Open Access Journals (Sweden)

    Antonio M. DE RON

    2016-08-01

    Full Text Available Rapid and uniform seed germination and seedling emergence under diverse environmental conditions is a desirable characteristic for crops. Common bean genotypes (Phaseolus vulgaris L. differ in their low temperature tolerance regarding growth and yield. Cultivars tolerant to low temperature during the germination and emergence stages and carriers of the grain quality standards demanded by consumers are needed for the success of the bean crop. The objectives of this study were i to screen the seedling emergence and the phenotypic response of bean germplasm under a range of temperatures in controlled chamber and field conditions to display stress-tolerant genotypes with good agronomic performances and yield potential, and ii to compare the emergence of bean seedlings under controlled environment and in open field conditions to assess the efficiency of genebanks standard germination tests for predicting the performance of the seeds in the field. Three trials were conducted with 28 dry bean genotypes in open field and in growth chamber under low, moderate and warm temperature. Morpho-agronomic data were used to evaluate the phenotypic performance of the different genotypes. Cool temperatures resulted in a reduction of the rate of emergence in the bean genotypes, however, emergence and early growth of bean could be under different genetic control and these processes need further research to be suitably modeled. Nine groups arose from the Principal Component Analysis (PCA representing variation in emergence time and proportion of emergence in the controlled chamber and in the open field indicating a trend to lower emergence in large and extra-large seeded genotypes. Screening of seedling emergence and phenotypic response of the bean germplasm under a range of temperatures in controlled growth chambers and under field conditions showed several genotypes, as landraces 272, 501, 593 and the cultivar Borlotto, with stress-tolerance at emergence and high

  10. Mass Communication in Ferment: Open Questions in the Historiography of the Field.

    Science.gov (United States)

    Robinson, Gertrude J.

    Thomas S. Kuhn's paradigm theory, which explains the growth of science, can be used to challenge three aspects of the received history of North American communications research: (1) the beginning point of the field and its periodization, (2) the development of mass media studies as an articulated subfield, and (3) the role of new technologies in…

  11. Opening Options: Making Field Education Work in a Private Practice Clinic Setting

    Science.gov (United States)

    Mooradian, John K.; Knaggs, Constance; Hock, Robert; LaCharite, David

    2011-01-01

    This article describes the use of social work field placements in a private practice setting to prepare MSW students for clinical work. The authors used "autoethnography", which is personal narrative that explores the writer's experience of life, to describe interpersonal and contextual characteristics, as well as procedures implemented to conduct…

  12. Mass Communication in Ferment: Open Questions in the Historiography of the Field.

    Science.gov (United States)

    Robinson, Gertrude J.

    Thomas S. Kuhn's paradigm theory, which explains the growth of science, can be used to challenge three aspects of the received history of North American communications research: (1) the beginning point of the field and its periodization, (2) the development of mass media studies as an articulated subfield, and (3) the role of new technologies in…

  13. Transient behavior of a flare-associated solar wind. I - Gas dynamics in a radial open field region

    Science.gov (United States)

    Nagai, F.

    1984-01-01

    A numerical investigation is conducted into the way in which a solar wind model initially satisfying both steady state and energy balance conditions is disturbed and deformed, under the assumption of heating that correspoonds to the energy release of solar flares of an importance value of approximately 1 which occur in radial open field regions. Flare-associated solar wind transient behavior is modeled for 1-8 solar radii. The coronal temperature around the heat source region rises, and a large thermal conductive flux flows inward to the chromosphere and outward to interplanetary space along field lines. The speed of the front of expanding chromospheric material generated by the impingement of the conduction front on the upper chromosphere exceeds the local sound velocity in a few minutes and eventually exceeds 100 million cm/sec.

  14. Pelagic habitat visualization: the need for a third (and fourth) dimension: HabitatSpace

    Science.gov (United States)

    Beegle-Krause, C; Vance, Tiffany; Reusser, Debbie; Stuebe, David; Howlett, Eoin

    2009-01-01

    Habitat in open water is not simply a 2-D to 2.5-D surface such as the ocean bottom or the air-water interface. Rather, pelagic habitat is a 3-D volume of water that can change over time, leading us to the term habitat space. Visualization and analysis in 2-D is well supported with GIS tools, but a new tool was needed for visualization and analysis in four dimensions. Observational data (cruise profiles (xo, yo, z, to)), numerical circulation model fields (x,y,z,t), and trajectories (larval fish, 4-D line) need to be merged together in a meaningful way for visualization and analysis. As a first step toward this new framework, UNIDATA’s Integrated Data Viewer (IDV) has been used to create a set of tools for habitat analysis in 4-D. IDV was designed for 3-D+time geospatial data in the meteorological community. NetCDF JavaTM libraries allow the tool to read many file formats including remotely located data (e.g. data available via OPeNDAP ). With this project, IDV has been adapted for use in delineating habitat space for multiple fish species in the ocean. The ability to define and visualize boundaries of a water mass, which meets specific biologically relevant criteria (e.g., volume, connectedness, and inter-annual variability) based on model results and observational data, will allow managers to investigate the survival of individual year classes of commercially important fisheries. Better understanding of the survival of these year classes will lead to improved forecasting of fisheries recruitment.

  15. Subseafloor basalts as fungal habitats

    Science.gov (United States)

    Ivarsson, M.

    2012-09-01

    The oceanic crust is believed to host the largest potential habitat for microbial life on Earth, yet, still we lack substantial information about the abundance, diversity, and consequence of its biosphere. The last two decades have involved major research accomplishments within this field and a change in view of the ocean crust and its potential to harbour life. Here fossilised fungal colonies in subseafloor basalts are reported from three different seamounts in the Pacific Ocean. The fungal colonies consist of various characteristic structures interpreted as fungal hyphae, fruit bodies and spores. The fungal hyphae are well preserved with morphological characteristics such as hyphal walls, septa, thallic conidiogenesis, and hyphal tips with hyphal vesicles within. The fruit bodies consist of large (∼50-200 µm in diameter) body-like structures with a defined outer membrane and an interior filled with calcite. The fruit bodies have at some stage been emptied of their contents of spores and filled by carbonate-forming fluids. A few fruit bodies not filled by calcite and with spores still within support this interpretation. Spore-like structures (ranging from a few µm to ∼20 µm in diameter) are also observed outside of the fruit bodies and in some cases concentrated to openings in the membrane of the fruit bodies. The hyphae, fruit bodies and spores are all closely associated with a crust lining the vein walls that probably represent a mineralized biofilm. The results support a fungal presence in deep subseafloor basalts and indicate that such habitats were vital between ∼81 and 48 Ma.

  16. Towards an Open Software Platform for Field Robots in Precision Agriculture

    OpenAIRE

    Kjeld Jensen; Morten Larsen; Nielsen, Søren H.; Leon B. Larsen; Kent S. Olsen; Rasmus N. Jørgensen

    2014-01-01

    Robotics in precision agriculture has the potential to improve competitiveness and increase sustainability compared to current crop production methods and has become an increasingly active area of research. Tractor guidance systems for supervised navigation and implement control have reached the market, and prototypes of field robots performing precision agriculture tasks without human intervention also exist. But research in advanced cognitive perception and behaviour that is required to ena...

  17. Open field release of genetically engineered sterile male Aedes aegypti in Malaysia.

    Directory of Open Access Journals (Sweden)

    Renaud Lacroix

    Full Text Available BACKGROUND: Dengue is the most important mosquito-borne viral disease. In the absence of specific drugs or vaccines, control focuses on suppressing the principal mosquito vector, Aedes aegypti, yet current methods have not proven adequate to control the disease. New methods are therefore urgently needed, for example genetics-based sterile-male-release methods. However, this requires that lab-reared, modified mosquitoes be able to survive and disperse adequately in the field. METHODOLOGY/PRINCIPAL FINDINGS: Adult male mosquitoes were released into an uninhabited forested area of Pahang, Malaysia. Their survival and dispersal was assessed by use of a network of traps. Two strains were used, an engineered 'genetically sterile' (OX513A and a wild-type laboratory strain, to give both absolute and relative data about the performance of the modified mosquitoes. The two strains had similar maximum dispersal distances (220 m, but mean distance travelled of the OX513A strain was lower (52 vs. 100 m. Life expectancy was similar (2.0 vs. 2.2 days. Recapture rates were high for both strains, possibly because of the uninhabited nature of the site. CONCLUSIONS/SIGNIFICANCE: After extensive contained studies and regulatory scrutiny, a field release of engineered mosquitoes was safely and successfully conducted in Malaysia. The engineered strain showed similar field longevity to an unmodified counterpart, though in this setting dispersal was reduced relative to the unmodified strain. These data are encouraging for the future testing and implementation of genetic control strategies and will help guide future field use of this and other engineered strains.

  18. Blanding’s Turtle (Emydoidea blandingii Potential Habitat Mapping Using Aerial Orthophotographic Imagery and Object Based Classification

    Directory of Open Access Journals (Sweden)

    Douglas J. King

    2012-01-01

    Full Text Available Blanding’s turtle (Emydoidea blandingii is a threatened species under Canada’s Species at Risk Act. In southern Québec, field based inventories are ongoing to determine its abundance and potential habitat. The goal of this research was to develop means for mapping of potential habitat based on primary habitat attributes that can be detected with high-resolution remotely sensed imagery. Using existing spring leaf-off 20 cm resolution aerial orthophotos of a portion of Gatineau Park where some Blanding’s turtle observations had been made, habitat attributes were mapped at two scales: (1 whole wetlands; (2 within wetland habitat features of open water, vegetation (used for camouflage and thermoregulation, and logs (used for spring sun-basking. The processing steps involved initial pixel-based classification to eliminate most areas of non-wetland, followed by object-based segmentations and classifications using a customized rule sequence to refine the wetland map and to map the within wetland habitat features. Variables used as inputs to the classifications were derived from the orthophotos and included image brightness, texture, and segmented object shape and area. Independent validation using field data and visual interpretation showed classification accuracy for all habitat attributes to be generally over 90% with a minimum of 81.5% for the producer’s accuracy of logs. The maps for each attribute were combined to produce a habitat suitability map for Blanding’s turtle. Of the 115 existing turtle observations, 92.3% were closest to a wetland of the two highest suitability classes. High-resolution imagery combined with object-based classification and habitat suitability mapping methods such as those presented provide a much more spatially explicit representation of detailed habitat attributes than can be obtained through field work alone. They can complement field efforts to document and track turtle activities and can contribute to

  19. Orthopedic and interventional applications at low field MRI with horizontally open configuration

    Energy Technology Data Exchange (ETDEWEB)

    Koskinen, S.K.; Parkkola, R.K.; Karhu, J.; Komu, M.E.S.; Kormano, M.J. [Diagnostic Radiology, Turku Univ. Hospital (Finland)

    1997-10-01

    The recently introduced horizontally open configuration imagers allow imaging of knee, hip or shoulder during whole range of motion, which is not possible in conventional MR imagers. Special joint motion devices can be used to provide accurate and reproducible studies. In cervical spine, functional MR imaging may be useful in evaluating alarligament stability in patients with late sequelae of a whiplash injury, and in patients with rheumatoid arthritis who are clinically suspected of having a cervical myelopathy or superior migration of the odontoid process. In shoulder, full range of motion abduction study may be helpful in assessing the supraspinatus tendon impingement. To evaluate patellofemoral malalignment, quadriceps loading is recommended since associated contracting muscles and related soft tissue structures can be evaluated. The position of the femoral head relative to the acetabulum during different positions can be assessed. Open-configuration scanners provide an access to patients during scanning procedure, and therefore permit interventional procedures to be monitored with MRI. Such interventions include aspiration cytology/biopsy and different drainage procedures. (orig.) [Deutsch] Die kuerzlich eingefuehrten bildgebenden Systeme mit horizontal offener Konfiguration ermoeglichen die Darstellung von Knie, Huefte oder Schulter ueber den gesamten Bewegungsbereich, war bisher mit konventionellen MR-Systemen nicht moeglich. Fuer genauere und reproduzierbare Untersuchungen koennen spezielle Gelenkbewegungsgeraete verwendet werden. Bei der Halswirbelsaeule kann die funktionelle NMR-Darstellung im Hinblick auf die Beurteilung der Stabilitaet der Ligamenta alaria bei Patienten mit Spaetfolgen eines Schleudertraumas und bei Patienten mit rheumatoider Arthritis von Nutzen sein, wenn klinisch eine zervikale Myelopathie oder superiore migration des Dens axis vermutet wird. Bei der Schulter kann eine Abduktionsstudie des vollen Bewegungsbereichs bei der Beurteilung

  20. Subchronic Oral Bromocriptine Methanesulfonate Enhances Open Field Novelty-Induced Behavior and Spatial Memory in Male Swiss Albino Mice

    Directory of Open Access Journals (Sweden)

    Olakunle James Onaolapo

    2013-01-01

    Full Text Available This study set out to assess the neurobehavioral effects of subchronic, oral bromocriptine methanesulfonate using the open field and the Y-maze in healthy male mice. Sixty adult Swiss albino mice were assigned into three groups. Controls received normal saline, while test groups received bromocriptine methanesulfonate at 2.5 and 5 mg/kg/day, respectively, for a period of 21 days. Neurobehavioral tests were carried out on days 1 and 21 after administration. Open field assessment on day 1 after administration revealed significant increase in grooming at 2.5 and 5 mg/kg, while horizontal and vertical locomotion showed no significant changes. Day 1 also showed no significant changes in Y-maze alternation. On day 21, horizontal locomotion, rearing, and grooming were increased significantly at 2.5 and 5 mg/kg doses after administration; also, spatial memory was significantly enhanced at 2.5 mg/kg. In conclusion, the study demonstrates the ability of oral bromocriptine to affect neurobehavior in normal mice. It also suggests that there is a cumulative effect of oral bromocriptine on the behaviors studied with more changes being seen after subchronic administration rather than after a single oral dose.

  1. Diazepam-induced decrease in anxiety-like behaviors of marmoset monkeys exposed to a novel open-field.

    Science.gov (United States)

    Cagni, Priscila; Komorowski, Mara; Melo, Gabriela C; Lima, Talita; Barros, Marilia

    2012-01-01

    Unfamiliar environments can be a source of stress, fear and anxiety for marmoset monkeys. In spite of existing data, the influence of putative anxiolytics on the effects of novel environments has yet to be tested in primates. Therefore, the behavior of adult black tufted-ear marmosets to a single brief (15 min) exposure to a novel environment was analyzed in the presence and absence of diazepam (DZP). Marmosets were pre-treated with vehicle (n=5) or diazepam (0.5 mg/kg, ip; n=5) and submitted to a 15 min free exploration trial within a rectangular open-field arena. DZP-treated subjects, compared to vehicle controls, demonstrated significantly lower rates of (phee) contact calls and exploration, while a higher scan duration. Sojourn time in the arena's central zone was also significantly higher in the former group and sedation was not observed. Thus, pre-treatment with the benzodiazepine DZP decreased several anxiety-related behaviors induced by subjecting the marmosets to a new environment. The results also indicate that, as with rodent subjects, the open-field may provide a useful simple paradigm for assessing anxiety-like behaviors in this primate and, as such, constitutes a unique opportunity for direct comparative studies between rodents and marmoset monkeys in terms of anxiety and/or sedation.

  2. Safety Evaluation of Self-assembling Peptide Gel after Intracranial Administration to Rats Using the Open Field Test.

    Science.gov (United States)

    Tsunoda, Masashi; Sugaya, Chiemi; Sugiura, Yumiko; Nagai, Yusuke; Sakanishi, Kotaro

    2016-01-01

    Self-assembling peptides have been developed as clinical materials, which could scaffold to regenerate nerve cells and hemostatic materials in vivo. However, there has not been enough information for their in vivo application. The safety of self-assembling peptides for the application on the brain was examined using behavioral tests for each rat in this study. Self-assembling peptide gel was administered to the surface of the brain at a volume of 20 µL at 1.5%. After 2 months, the open field test and the prepulse inhibition (PPI) test were performed. There were no significant differences between the peptide gel and the control groups in locomotor distances and in %PPIs in the PPI test. The mean values of the percentage of time the rats stayed in the central area of the open field during the first 5 min and instances of center rearing or face washing in the peptide gel group were significantly higher than those in the control. There were amorphous substance in the subarachnoid region, and infiltrations of mononuclear cells were also observed in the self-assembling peptide gel group. Although the meaning of the effects observed in this study was not fully elucidated, the self-assembling gel produced marginal but significant behavioral and histological effects.

  3. Contrast-enhanced breast MR imaging of claustrophobic or oversized patients using an open low-field magnet.

    Science.gov (United States)

    Calabrese, M; Brizzi, D; Carbonaro, L; Chiaramondia, M; Kirchin, M A; Sardanelli, F

    2009-03-01

    A number of women who should undergo magnetic resonance (MR) imaging of the breast cannot use this diagnostic tool due to claustrophobia or excessive body size for the restricted confines of standard closed MR systems. Our aim was to evaluate the performance of open low-field magnet breast MR imaging in such patients using a high-relaxivity contrast agent. Of 397 consecutive patients undergoing breast MR imaging, 379 (95.5%) were studied at 1.5 T. Due to claustrophobia (n=15) or large body size (n=3), 18 patients (4.5%) were studied on a 0.2-T open magnet using a body coil. A 3D dynamic T1-weighted gradient-echo 94-s sequence was acquired with intravenous injection of gadobenate dimeglumine (0.1 mmol/kg). The standard of reference was pathological examination for 16 lesions classified with a maximal Breast Imaging Reporting and Data System (BI-RADS) score from 3 to 5, fine-needle aspiration cytology and >or=2-year follow-up for two lesions classified as BI-RADS 3, and >or=2-years follow-up for five lesions classified as BI-RADS 2. Diagnostic MR image quality was achieved for 20/23 lesions in 15/18 patients. Three lesions (two invasive cancers and a cyst) were not assessed due to patient movement and considered as two false negatives and one false positive. Thus, an 86% sensitivity [13/15; 95% confidence interval (CI): 70%-100%], an 87% specificity (7/8; 95% CI: 65%-100%) and an 87% accuracy (20/23; 95% CI: 73%-100%) were obtained. The intraclass correlation coefficient between MR and pathologic lesion size was 0.845. In claustrophobic or oversized patients, open low-field breast MR with gadobenate dimeglumine yields good diagnostic performance.

  4. A search for white dwarfs in the Galactic plane: the field and the open cluster population

    CERN Document Server

    Raddi, R; Gaensicke, B T; Hermes, J J; Napiwotzki, R; Koester, D; Tremblay, P -E; Barentsen, G; Farnhill, J H; Mohr-Smith, M; Drew, J E; Groot, P J; Guzman-Ramirez, L; Parker, Q A; Steeghs, D; Zijlstra, A

    2016-01-01

    We investigated the prospects for systematic searches of white dwarfs at low Galactic latitudes, using the VLT Survey Telescope (VST) H$\\alpha$ Photometric Survey of the Galactic plane and Bulge (VPHAS+). We targeted 17 white dwarf candidates along sightlines of known open clusters, aiming to identify potential cluster members. We confirmed all the 17 white dwarf candidates from blue/optical spectroscopy, and we suggest five of them to be likely cluster members. We estimated progenitor ages and masses for the candidate cluster members, and compared our findings to those for other cluster white dwarfs. A white dwarf in NGC 3532 is the most massive known cluster member (1.13 M$_{\\odot}$), likely with an oxygen-neon core, for which we estimate an $8.8_{-4.3}^{+1.2}$ M$_{\\odot}$ progenitor, close to the mass-divide between white dwarf and neutron star progenitors. A cluster member in Ruprecht 131 is a magnetic white dwarf, whose progenitor mass exceeded 2-3 M$_{\\odot}$. We stress that wider searches, and improved...

  5. Fascicular Visual Field Defects in Open-Angle Glaucoma: Evaluation with Microperimetry.

    Science.gov (United States)

    Arrico, Loredana; Giannotti, Rossella; Fratipietro, Manuela; Malagola, Romualdo

    2016-01-01

    Purpose. Use of microperimetry (Mp-1), correlating with Humphrey perimetry (30-2 program), in patients affected by primary open-angle glaucoma (POAG) with perimetric defects, in order to obtain an evaluation of the accuracy of the results obtained by Mp-1. Materials and Methods. In this study 40 eyes of 25 patients affected by POAG with perimetric defects were included. All patients underwent microperimetry test by Nidek Mp-1 (NAVIS software version 1.7.2, Nidek Technologies). Mean sensitivity values expressed in decibel (dB) of all tested dots and mean values for each quadrant obtained by microperimetric test were correlated with corresponding quadrants obtained by static perimetry analysis. Data were analyzed by Pearson's correlation and Bland-Altman analysis. Results. Interpolated data showed that mean sensitivity values in all spots tested by Mp-1 (11.98 dB, SD 4.31) may be significantly correlated with mean total values obtained by Humphrey 30-2 perimetry (17.95, SD 4.32), with correlation coefficient of 0.556. Conclusions. Topographic visualization of the perimetric alteration by microperimetry allows retesting areas with reduced sensitivity which are topographically visualized and displayable on the ocular fundus examination, avoiding worsening of the functional defect by better modulation of the antiglaucoma therapy and therefore it allows better monitoring of the pathologic functional damage.

  6. First field demonstration of cloud datacenter workflow automation employing dynamic optical transport network resources under OpenStack and OpenFlow orchestration.

    Science.gov (United States)

    Szyrkowiec, Thomas; Autenrieth, Achim; Gunning, Paul; Wright, Paul; Lord, Andrew; Elbers, Jörg-Peter; Lumb, Alan

    2014-02-10

    For the first time, we demonstrate the orchestration of elastic datacenter and inter-datacenter transport network resources using a combination of OpenStack and OpenFlow. Programmatic control allows a datacenter operator to dynamically request optical lightpaths from a transport network operator to accommodate rapid changes of inter-datacenter workflows.

  7. Habitat Impact on Ultraviolet Reflectance in Moths.

    Science.gov (United States)

    Zapletalová, L; Zapletal, M; Konvička, M

    2016-10-01

    A comparison of 95 species of Central European moths, representing 11 families and inhabiting various habitats, was carried out in order to detect the potential impact of biotope on the ultraviolet (UV) light reflectance of their wings. Based on digitized photographs taken under UV light conditions, a phylogeny-controlled redundancy analysis relating UV reflectance to preferred habitat type (xerophilous, mesophilous, and hygrophilous) and habitat openness (open, semiopen, and closed) was carried out. Species preferring hygrophilous habitats displayed significantly higher UV wing reflectance than species inhabiting xerothermic and mesic habitats, and this pattern remained significant even after controlling for phyletic relationships. In contrast, UV wing reflectance displayed no pattern related to habitat openness. Given the higher UV reflectance of water and humid surfaces, we interpret these results, which are based on the first comprehensive sampling of UV reflectance in Central European moths, in terms of predator avoidance under habitat-specific light conditions. We conclude that the moisture content of the environment may markedly contribute to the variation of appearance of moth wings for better imitation habitat characteristics and therefore to increase protection. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. 基于OpenGL的动态模拟星空设计%Design of Simulation Star Field Based on OpenGL

    Institute of Scientific and Technical Information of China (English)

    张京

    2007-01-01

    基于OpenGL的动态模拟星空,用MFC建立OpenGL场景.采用OpenGL的辅助库画立体球体,把恒星的球面坐标转化为三维直角坐标,用恒星的点坐标建立显示列表,再根据恒星互相连接编号进行连线并建立星座显示列表.具体步骤包括OpenGL初始化、设置OpenGL场景、恒星坐标转换、建立模拟星空显示列表、设置视图变换及显示模拟星空.

  9. Estimation of the Aral Sea state predictability based on the open data sources and the unique field observations

    Science.gov (United States)

    Izhitskiy, Alexander; Ayzel, Georgy; Zavialov, Peter; Kurbaniyazov, Abilgazi

    2016-04-01

    The Aral Sea, formerly one of the four largest lakes in the world, has lost over 90% of its volume during the dramatical dessication mainly caused by the severe alteration of water budget of the basin. Shrinkage of the Aral Sea resulted in profound changes of the lake's ecosystem, that became a subject for a number of publications based on a wide range of methods such as field observations, remote sensing data analysis and numerical modeling. However, by the early 21th century, the number of field studies decreased significantly due to almost complete cessation of navigation and displacement of the Aral's shoreline far away from roads and other infrastructure. Thus, only a small amount of field data (salinity, temperature, etc.) for different regions of the lake is available for the last two decades. On the other hand, a set of the open data sources (sea level variability, atmospheric reanalysis) were developed for the region. The main idea of the presented study is to estimate the possibility of prediction of the Aral Sea state using coupled system of basic geoanalysis tools, numerical modeling of hydrological cycle (both for sea and land-surface interactions with atmosphere) and state-of-art machine learning techniques. Firstly, available in situ data, obtained in the Aral Sea by Shirshov Institute and other researchers, are concerned as the "base points of state" for each year within the studied period. Secondly, consistent patterns in the interannual variability of all other available parameters, taken from the open data sources and numerical modeling predictions, are founded out. As a result, such an approach allows predicting the future state of sea basing on the possible climatic scenario.

  10. A High-Throughput, Field-Based Phenotyping Technology for Tall Biomass Crops1[OPEN

    Science.gov (United States)

    2017-01-01

    Recent advances in omics technologies have not been accompanied by equally efficient, cost-effective, and accurate phenotyping methods required to dissect the genetic architecture of complex traits. Even though high-throughput phenotyping platforms have been developed for controlled environments, field-based aerial and ground technologies have only been designed and deployed for short-stature crops. Therefore, we developed and tested Phenobot 1.0, an auto-steered and self-propelled field-based high-throughput phenotyping platform for tall dense canopy crops, such as sorghum (Sorghum bicolor). Phenobot 1.0 was equipped with laterally positioned and vertically stacked stereo RGB cameras. Images collected from 307 diverse sorghum lines were reconstructed in 3D for feature extraction. User interfaces were developed, and multiple algorithms were evaluated for their accuracy in estimating plant height and stem diameter. Tested feature extraction methods included the following: (1) User-interactive Individual Plant Height Extraction (UsIn-PHe) based on dense stereo three-dimensional reconstruction; (2) Automatic Hedge-based Plant Height Extraction (Auto-PHe) based on dense stereo 3D reconstruction; (3) User-interactive Dense Stereo Matching Stem Diameter Extraction; and (4) User-interactive Image Patch Stereo Matching Stem Diameter Extraction (IPaS-Di). Comparative genome-wide association analysis and ground-truth validation demonstrated that both UsIn-PHe and Auto-PHe were accurate methods to estimate plant height, while Auto-PHe had the additional advantage of being a completely automated process. For stem diameter, IPaS-Di generated the most accurate estimates of this biomass-related architectural trait. In summary, our technology was proven robust to obtain ground-based high-throughput plant architecture parameters of sorghum, a tall and densely planted crop species. PMID:28620124

  11. Association of Myopic Deformation of Optic Disc with Visual Field Progression in Paired Eyes with Open-Angle Glaucoma

    Science.gov (United States)

    Hangai, Masanori; Ishikawa, Makoto; Yoshitomi, Takeshi

    2017-01-01

    Purpose The influence of myopia on glaucoma progression remains unknown, possibly because of the multifactorial nature of glaucoma and difficulty in assessing a solo contribution of myopia. The purpose of this study is to investigate the association of myopia with visual field (VF) progression in glaucoma using a paired-eye design to minimize the influence of confounding systemic factors that are diverse among individuals. Methods This retrospective study evaluated 144 eyes of 72 subjects with open-angle glaucoma, with similar intra-ocular pressure between paired eyes, spherical equivalent (SE) ≤ -2 diopter (D), and axial length ≥ 24 mm. Paired eyes with faster and slower VF progression were grouped separately, according to the global VF progression rate assessed by automated pointwise linear regression analysis. The SE, axial length, tilt ratio and torsion angle of optic discs, Bruch’s membrane (BM) opening area, and gamma zone parapapillary atrophy (PPA) width were compared between the two groups. Factors associated with faster VF progression were determined by logistic regression analysis. Results The mean follow-up duration was 8.9 ± 4.4 years. The mean value of SE and axial length were -6.31 ± 1.88 D and 26.05 ± 1.12 mm, respectively. The mean global visual field progression rate was -0.32 ± 0.38 dB/y. Tilt ratio, BM opening area, and gamma zone PPA width were significantly greater in the eyes with faster VF progression than those with slower progression. In multivariate analysis, these factors were significantly associated with faster VF progression (all P < 0.05), while SE and axial length were not associated with it. Conclusion In myopic glaucoma subjects, tilt of the optic disc and temporal shifting and enlargement of the BM opening were associated with faster rate of VF progression between paired eyes. This suggests that myopia influences VF progression in glaucomatous eyes via optic disc deformations rather than via refractive error itself

  12. Cross-field motion of plasma blob-filaments and related particle flux in an open magnetic field line configuration on QUEST

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H.Q., E-mail: hqliu@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga, Fukuoka 8168580 (Japan); Hanada, K. [Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 8168580 (Japan); Nishino, N. [Graduate School of Engineering, Hiroshima University, Hiroshima 7398511 (Japan); Ogata, R.; Ishiguro, M. [Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga, Fukuoka 8168580 (Japan); Gao, X. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Zushi, H.; Nakamura, K.; Fujisawa, A.; Idei, H.; Hasegawa, M. [Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 8168580 (Japan)

    2013-07-15

    Blob-filaments have been observed by combined measurement with a fast camera and a movable Langmuir probe in an open magnetic field line configuration of electron cyclotron resonance (ECR) heating plasma in QUEST. Blob-filaments extended along field lines do correspond to over-dense plasma structures and propagated across the field lines to the outer wall. The radial velocity of the blob structure, V{sub b}, was obtained by three methods and was dominantly driven by the E × B force. The radial velocity, size of the blob showed good agreements with the results obtained by sheath-connected interchange theoretical model. V{sub b} corresponds to roughly 0.02–0.07 of the local sound speed (C{sub s}) in QUEST. The higher moments (skewness S and kurtosis K) representing the shape of PDF of density fluctuation are studied. Their least squares fitting with quadratic polynomial is K = (1.60 ± 0.27)S{sup 2} − (0.46 ± 0.20). The larger blob structures, occurring only 10% of the time, can carry more than 60% loss of the entire radial particle flux.

  13. Antagonism of meta-chlorophenylpiperazine-induced inhibition of exploratory activity in an emergence procedure, the open field test, in rats.

    Science.gov (United States)

    Meert, T F; Melis, W; Aerts, N; Clincke, G

    1997-08-01

    The effects of meta-chlorophenylpiperazine (mCPP) were studied on exploratory behaviour in the open field test, using a procedure designed to evaluate the emergence of rats into a novel environment. mCPP reduced the exploratory activity in a dose-related manner after subcutaneous (s.c.), intraperitoneal (i.p.) and intravenous (i.v.) administration. The inhibition was manifest in all the parameters used to quantify the exploration of the open field area. Additional neuroendocrine experiments in a parallel group of rats revealed a dose-related increase in plasma prolactin and ACTH levels after i.v. mCPP, pointing to a general state of arousal in these mCPP-treated animals. A number of 5-HT antagonists were tested for their ability to prevent or reverse the behavioural inhibition induced by an i.v. injection of 1.0 g/kg mCPP given 15 min before testing in the open field. The antagonists were injected s.c. or given orally at various time intervals before mCPP, or they were injected i.v. 10 min after mCPP. The lowest active doses for the attentuation of the mCPP-induced behavioural inhibition after s.c., oral and i.v. administration, respectively, were 0.04, 40 and 10 mg/kg for pizotifen; 0.16, 0.16 and 0.16 mg/kg for mianserin; 0.63, 0.16 and 0.16 mg/kg for methysergide, and 0.16, 2.5 and 2.5 mg/kg for ritanserin. The lowest active doses of mirtazapine after s.c. and i.v. treatment were 0.01 and 0.16 mg/kg. These data indicate that mixed 5-HT1/5-HT2 receptor antagonists such as pizotifen and methysergide, and mixed 5-HT and catecholamine antagonists such as mianserin and mirtazapine are more potent antagonists of mCPP-induced behavioural inhibition in rats than the more selective 5-HT2A/5-HT2C antagonist ritanserin.

  14. Estimating the Rate of Progressive Visual Field Damage in Those with Open-Angle Glaucoma, from Cross-Sectional Data

    Science.gov (United States)

    Broman, Aimee Teo; Quigley, Harry A.; West, Sheila K.; Katz, Joanne; Munoz, Beatriz; Bandeen-Roche, Karen; Tielsch, James M.; Friedman, David S.; Crowston, Jonathan; Taylor, Hugh R.; Varma, Rohit; Leske, M. Cristina; Bengtsson, Boel; Heijl, Anders; He, Mingguang; Foster, Paul J.

    2008-01-01

    Purpose To estimate the rate of visual field progression in open-angle glaucoma (OAG) subjects, by using data from population-based cross-sectional studies. Methods Subjects with OAG were identified in nine surveys of randomly sampled populations using standard criteria for glaucomatous optic neuropathy. Subjects were of European, African, Chinese, and Hispanic ethnicity. The measure of OAG damage was the mean deviation (MD) of an automated visual field test (Humphrey Field Analyzer; Carl Zeiss Meditec, Inc., Dublin, CA). The rate of progression was the mean of all subjects’ damage in the worse eye divided by an average time since onset. Time since onset was estimated from age-specific prevalence rates. Results A total of 1066 subjects with OAG contributed visual field data. The mean worsening in decibels per year was: European-derived, −1.12; Hispanic, −1.26; African-derived, −1.33; and Chinese −1.56 (difference among ethnicities, P = 0.16). The mean duration of disease was lowest among Chinese persons at 10.5 years (95% CI: 8.8–12.6) and was highest in African-derived subjects at 15.4 years (95% CI: 14.6–15.9). The progression rate was not consistently related to age or gender. By combining disease duration and progression rate, the model predicted that 15% or fewer of the worse eyes would reach the end of the field damage scale in the patient’s lifetime. Conclusions The estimates of typical worsening per year in the worse eye among subjects with OAG suggested slightly more rapid progression than in some clinic-based studies. The rate did not differ significantly by ethnicity or gender, but was worse in those with known, treated OAG and in pseudophakic subjects. PMID:18172076

  15. Effective field theory approach to open heavy flavor production in heavy-ion collisions

    CERN Document Server

    Kang, Zhong-Bo; Vitev, Ivan

    2016-01-01

    We develop a version of Soft Collinear Effective Theory (SCET) which includes finite quark masses, as well as Glauber gluons that describe the interaction of collinear partons with QCD matter. In the framework of this new effective field theory, labeled SCET$_{\\mathrm{M,G}}$, we derive the massive splitting functions in the vacuum and the QCD medium for the processes $Q\\to Qg$, $Q\\to gQ$ and $g\\to Q\\bar Q$. The numerical effects due to finite quark masses are sizable and our results are consistent with the traditional approach to parton energy loss in the soft gluon emission limit. In addition, we present a new framework for including the medium-induced full splitting functions consistent with next-to-leading order calculations in QCD for inclusive hadron production. Finally, we show numerical results for the suppression of $D$- and $B$-mesons in heavy ion collisions at $\\sqrt{s_{\\mathrm{NN}}}=5.02$ TeV and 2.76 TeV and compare to available data from the LHC.

  16. Violet LED light enhances the recruitment of a thrip predator in open fields

    Science.gov (United States)

    Ogino, Takumi; Uehara, Takuya; Muraji, Masahiko; Yamaguchi, Terumi; Ichihashi, Takahisa; Suzuki, Takahiro; Kainoh, Yooichi; Shimoda, Masami

    2016-01-01

    The predatory bug Orius sauteri is an indigenous natural enemy of thrips and whiteflies in Asian countries. To put these bugs to practical use in pest management, methods to attract and retain the bugs in agricultural fields are needed. We previously showed that violet light (405 nm) attracts O. sauteri selectively. Many thrips and whiteflies are attracted to UV or green light. In this study, we examined the effect of violet-LED illumination on O. sauteri in pesticide-free eggplant (Solanum melongena L.) cultivation. In three cultivation trials, the density of O. sauteri on eggplant leaves was consistently higher in the illuminated plots; at least twice that of the non-illuminated plots. Simultaneously, the density of thrips declined markedly to less than half that of the non-illuminated plots. We identified three positive effects of violet light including an “immediate-effect” on predator attraction, a “persistent-effect” on predator reproduction, and a “secondary-effect” on the food web structure. Our results showed that illumination with violet light provides a powerful tool for integrated pest management. This is the first report on the use of illumination to manipulate the behavior of natural enemies. PMID:27604315

  17. First horizontal well opens new gas opportunities in the Sierra Chata Field Neuquen Basin-Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, C.A.; Nilson, G.J.; Acree, J.F.; Del Pino, M.A. [Devon Energy Corp., Calgary, AB (Canada); Anaya, L. [BJ Services Co. USA, Houston, TX (United States)

    2002-07-01

    This paper described the drilling activity surrounding the first horizontal re-entry gas well in the Sierra Chata field in the Neuquen basin in Argentina. In particular, a model forecast was compared with the final results. The re-entry well was originally designed to add gas reserves and to incorporate horizontal well technology to help access the thin sands with low permeability. A numeric simulation of the 1000 m horizontal well was used to predict an initial gas flow rate of 17.7 MMscfd with an estimated final recovery of 7.3 Bscf. This forecast was confirmed following the first year of production. Operational problems, however, were encountered and new solutions were needed to bring the well back on line. The use of an existing well bore saved $1 MM and improved the economics of the project. When re-entering the existing well bore, no new flow line was needed. Given the success of this first re-entry well, it was suggested that this technology can now be used for the Machiline formation which has low productivity for several reasons, including thin sands, low permeability and difficult access via vertical wells. The use of mud logs and resistivity/gamma ray logs while drilling was very important for geological control purposes. It was noted that a measurement while drilling (MWD) tool closer to the bit would have further improved the ability to stay within very thin target zones. 11 refs., 19 figs.

  18. Comparing Natural Gas Leakage Detection Technologies Using an Open-Source "Virtual Gas Field" Simulator.

    Science.gov (United States)

    Kemp, Chandler E; Ravikumar, Arvind P; Brandt, Adam R

    2016-04-19

    We present a tool for modeling the performance of methane leak detection and repair programs that can be used to evaluate the effectiveness of detection technologies and proposed mitigation policies. The tool uses a two-state Markov model to simulate the evolution of methane leakage from an artificial natural gas field. Leaks are created stochastically, drawing from the current understanding of the frequency and size distributions at production facilities. Various leak detection and repair programs can be simulated to determine the rate at which each would identify and repair leaks. Integrating the methane leakage over time enables a meaningful comparison between technologies, using both economic and environmental metrics. We simulate four existing or proposed detection technologies: flame ionization detection, manual infrared camera, automated infrared drone, and distributed detectors. Comparing these four technologies, we found that over 80% of simulated leakage could be mitigated with a positive net present value, although the maximum benefit is realized by selectively targeting larger leaks. Our results show that low-cost leak detection programs can rely on high-cost technology, as long as it is applied in a way that allows for rapid detection of large leaks. Any strategy to reduce leakage should require a careful consideration of the differences between low-cost technologies and low-cost programs.

  19. Louisiana ESI: HABITATS (Habitat and Plant Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for coastal habitats in Louisiana. Vector polygons represent various habitats, including marsh types, other...

  20. Lessons in modern digital field geology: Open source software, 3D techniques, and the new world of digital mapping

    Science.gov (United States)

    Pavlis, Terry; Hurtado, Jose; Langford, Richard; Serpa, Laura

    2014-05-01

    Although many geologists refuse to admit it, it is time to put paper-based geologic mapping into the historical archives and move to the full potential of digital mapping techniques. For our group, flat map digital geologic mapping is now a routine operation in both research and instruction. Several software options are available, and basic proficiency with the software can be learned in a few hours of instruction and practice. The first practical field GIS software, ArcPad, remains a viable, stable option on Windows-based systems. However, the vendor seems to be moving away from ArcPad in favor of mobile software solutions that are difficult to implement without GIS specialists. Thus, we have pursued a second software option based on the open source program QGIS. Our QGIS system uses the same shapefile-centric data structure as our ArcPad system, including similar pop-up data entry forms and generic graphics for easy data management in the field. The advantage of QGIS is that the same software runs on virtually all common platforms except iOS, although the Android version remains unstable as of this writing. A third software option we are experimenting with for flat map-based field work is Fieldmove, a derivative of the 3D-capable program Move developed by Midland Valley. Our initial experiments with Fieldmove are positive, particularly with the new, inexpensive (problem. As spatial databases evolve these 3D models should be readily importable into the database.

  1. Use of habitats by non-volant small mammals in Cerrado in Central Brazil.

    Science.gov (United States)

    Santos-Filho, M; Frieiro-Costa, F; Ignácio, Á R A; Silva, M N F

    2012-11-01

    Non-volant small mammals are organisms capable of yielding precise information on richness, abundance and species composition variations related to the use of habitats. The aim of this research was to compare these variations in Cerrado sensu stricto, Palm Forest, Gallery Forest and Rocky Field. From May 1999 to February 2000, we surveyed non-volant small mammals (hence small mammals) in Serra das Araras Ecological Station. We captured 218 individuals and recaptured 62 individuals, belonging to 21 taxa, 13 rodents and eight marsupials, in a total of 13200 trap-nights. Capture success was 1.7%. We observed higher richness of small mammals in forested areas (Gallery Forest and Palm Forest) than in open areas (Rocky Field and Cerrado sensu stricto). The Palm Forest had the highest richness of marsupials, possibly due to the quality of a specific niche. The Rocky Field had the smallest richness, but with very high abundance of few species, mainly Thrichomys pachyurus and Monodelphis domestica. Forest habitats had similar species composition. The open habitats, Cerrado sensu stricto and Rocky Field, had a distinct species composition between them, and also when compared to forested areas. Different species are exclusive or showed preference for specific habitats. The protection of horizontally heterogeneous biomes, such as Cerrado, has a fundamental importance to the maintenance of the regional diversity of the small mammal community of Central Brazil.

  2. EcologicHabitat_WLH

    Data.gov (United States)

    Vermont Center for Geographic Information — The Wildlife Linkage Habitat Analysis uses landscape scale data to identify or predict the location of potentially significant wildlife linkage habitats (WLH)...

  3. Variable stars in one open cluster within the Kepler/K2-Campaign-5 field: M 67 (NGC 2682)

    CERN Document Server

    Nardiello, D; Bedin, L R; Piotto, G; Ochner, P; Cunial, A; Borsato, L; Granata, V

    2015-01-01

    In this paper we continue the release of high-level data products from the multiyear photometric survey collected at the 67/92 cm Schmidt Telescope in Asiago. The primary goal of the survey is to discover and to characterise variable objects and exoplanetary transits in four fields containing five nearby open clusters spanning a broad range of ages. This second paper releases a photometric catalogue, in five photometric bands, of the Solar-age, Solar-metallicity open cluster M 67 (NGC 2682). Proper motions are derived comparing the positions observed in 2013 at the Asiago's Schmidt Telescope with those extracted from WFI@2.2m MPG/ESO images in 2000. We also analyse the variable sources within M 67. We detected 68 variables, 43 of which are new detection. Variable periods and proper-motion memberships of a large majority of sources in our catalogue are improved with respect to previous releases. The entire catalogue will be available in electronic format. Besides the general interest on an improved catalogue, ...

  4. Transient behavior of flare-associated solar wind. II - Gas dynamics in a nonradial open field region

    Science.gov (United States)

    Nagai, F.

    1984-01-01

    Transient behavior of flare-associated solar wind in the nonradial open field region is numerically investigated, taking into account the thermal and dynamical coupling between the chromosphere and the corona. A realistic steady solar wind is constructed which passes through the inner X-type critical point in the rapidly diverging region. The wind speed shows a local maximum at the middle, O-type, critical point. The wind's density and pressure distributions decrease abruptly in the rapidly diverging region of the flow tube. The transient behavior of the wind following flare energy deposition includes ascending and descending conduction fronts. Thermal instability occurs in the lower corona, and ascending material flows out through the throat after the flare energy input ceases. A local density distribution peak is generated at the shock front due to the pressure deficit just behind the shock front.

  5. Comments on new multiple-brane solutions based on Hata-Kojita duality in open string field theory

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Toru [Institute of Physics, The University of Tokyo,Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Department of Physics, Ochanomizu University,Otsuka, Bunkyo-ku, Tokyo 2-1-1 (Japan)

    2014-05-06

    Recently, Hata and Kojita proposed a new energy formula for a class of solutions in Witten’s open string field theory based on a novel symmetry of correlation functions they found. Their energy formula can be regarded as a generalization of the conventional energy formula by Murata and Schnabl. Following their proposal, we investigate their new ansatz for the classical solution representing double D-branes. We present a regularized definition of this solution and show that the solution satisfies the equation of motion when it is contracted with the solution itself and when it is contracted with any states in the Fock space. However, the Ellwood invariant and the boundary state of the solution are the same as those for the perturbative vacuum. This result disagrees with an expectation from the Ellwood conjecture.

  6. On the exact open-closed vertex in plane-wave light-cone string field theory

    CERN Document Server

    Lucietti, J; Sinha, A K; Lucietti, James; Schafer-Nameki, Sakura; Sinha, Aninda

    2003-01-01

    The open-closed vertex in the maximally supersymmetric type IIB plane-wave light-cone string field theory is considered and an explicit solution for the bosonic part of the vertex is derived, valid for all values of the mass parameter, \\mu. This vertex is of relevance to IIB plane-wave orientifolds, as well as IIB plane-wave strings in the presence of D-branes, and their gauge theory duals. Methods of complex analysis are used to develop a systematic procedure for obtaining the solution. This procedure is first applied to the vertex in flat space, and then extended to the plane-wave case. The plane-wave solution for the vertex requires introducing certain ``\\mu-deformed Gamma functions'', which are generalizations of the ordinary Gamma function. The behaviour of the Neumann matrices is graphically illustrated and their large-\\mu asymptotics are analysed.

  7. Multi-walled carbon nanotubes increase anxiety levels in rats and reduce exploratory activity in the open field test.

    Science.gov (United States)

    Sayapina, N V; Batalova, T A; Chaika, V V; Kuznetsov, V L; Sergievich, A A; Kolosov, V P; Perel'man, Yu M; Golokhvast, K S

    2015-01-01

    The results of the first study on the effects of multi-walled carbon nanotubes (MWNTs) on the exploratory activity and the emotional state in laboratory rats assessed by the open field test are reported. During three or ten days, rats received 8-10 nm MWNTs added to their food at a dose of 500 mg/kg. It was demonstrated that, in the group of rats which were fed with MWNTs, the integrated anxiety level index began to increase as early as the third day of the experiment; on the tenth day, it appeared to be twice increased. It was also demonstrated that MWNTs decreased the integrated exploratory activity index nearly twofold on the third day and nearly fourfold on the tenth day.

  8. A theoretical study of asymptotic boundary conditions for the numerical solutions of open-boundary static electromagnetic-field problems

    Institute of Scientific and Technical Information of China (English)

    马西奎; 韩社教

    2002-01-01

    Based on the multipole expansion theory of the potential, a satisfactory interpretation is put forward of the exact nature of the approximations of asymptotic boundary condition (called the ABC) techniques for the numerical solutions of open-boundary static electromagnetic-field problems, and a definite physical meaning is bestowed on ABC, which provide a powerful theoretical background for laying down the operating rules and the key to the derivation of asymptotic boundary conditions. This paper is also intended to reveal the shortcomings of the conventional higher-order ABC, and at the same time to give the concept of a new type of higher-order ABC, and to present a somewhat different formulation of the new nth-order ABC. In order to test its feasibility, several simple problems of electrostatic potentials are analyzed. The results are found to be much better than those of conventional higher-order ABCs.

  9. Relationship between consecutive deterioration of mean deviation value and progression of visual field defect in open-angle glaucoma

    Directory of Open Access Journals (Sweden)

    Naito T

    2015-11-01

    Full Text Available Tomoko Naito,1 Keiji Yoshikawa,2 Shiro Mizoue,3 Mami Nanno,4 Tairo Kimura,5 Hirotaka Suzumura,6 Ryuji Takeda,7 Fumio Shiraga1 1Department of Ophthalmology, Okayama University Graduate School of Medicine, Okayama, 2Yoshikawa Eye Clinic, Tokyo, 3Department of Ophthalmology, Ehime University Graduate School of Medicine, Ehime, 4Kagurazaka Minamino Eye Clinic, 5Ueno Eye Clinic, 6Suzumura Eye Clinic, Tokyo, 7Department of Agriculture, Kinki University, Nara, Japan Purpose: To analyze the relationship between consecutive deterioration of mean deviation (MD value and glaucomatous visual field (VF progression in open-angle glaucoma (OAG, including primary OAG and normal tension glaucoma.Patients and methods: The subjects of the study were patients undergoing treatment for OAG who had performed VF tests at least 10 times with a Humphrey field analyzer (SITA standard, C30-2 program. The VF progression was defined by a significantly negative MD slope (MD slope worsening at the final VF test during the follow-up period. The relationship between the MD slope worsening and the consecutive deterioration of MD value were retrospectively analyzed.Results: A total of 165 eyes of 165 patients were included in the analysis. Significant progression of VF defects was observed in 72 eyes of 72 patients (43.6%, while no significant progression was evident in 93 eyes of 93 patients (56.4%. There was significant relationship between the frequency of consecutive deterioration of MD value and MD slope worsening (P<0.0001, Cochran–Armitage trend test. A significant association was observed for MD slope worsening in the eyes with three (odds ratio: 2.1, P=0.0224 and four (odds ratio: 3.6, P=0.0008 consecutive deterioration of MD value in multiple logistic regression analysis, but no significant association in the eyes with two consecutive deterioration (odds ratio: 1.1, P=0.8282. The eyes with VF progression had significantly lower intraocular pressure reduction rate (P<0

  10. Control of the Tomato Leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), in Open-Field Tomatoes by Indigenous Natural Enemies Occurring in Israel.

    Science.gov (United States)

    Shaltiel-Harpaz, Liora; Gerling, Dan; Graph, Shaul; Kedoshim, Hendrika; Azolay, Lotem; Rozenberg, Tamir; Nachache, Yaakov; Steinberg, Shimon; Allouche, Arnon; Alon, Tamar

    2016-02-01

    The tomato leafminer, Tuta absoluta (Meyrick), had established in Israel by 2010, attacking both open-field tomatoes and greenhouse crops.We searched for its natural enemies in open-field tomatoes, and tried to determine their potential for controlling this pest. We surveyed the local natural enemies in open tomato fields and measured their impact on pest populations in an unsprayed field. We assessed the suppressive ability of the dominant hemipteran predator, Nesidiocoris tenuis Reuter, against T. absoluta under controlled laboratory conditions and evaluated the impact of its augmentation on T. absoluta control in open-field tomatoes. We found five natural enemy species:the predator, N. tenuis, two braconids, and two eulophids. Predation accounted for 64.5±9.2% (mean ± SE) of T. absoluta larval mortality, whereas parasitism accounted for 20.96±7.5%. Together, they eliminated the pest population at tomato harvest time. Under controlled conditions, predation by N. tenuis rose from 58 to 72% with increased density of T. absoluta, suggesting positive density dependence. The reduction of T. absoluta (83%) by N. tenuis was higher than that of Bemisia tabaci (32%), suggesting a preference of N. tenuis for T. absoluta. Augmentation of N.tenuis was as effective as conventional treatment insecticide treatment, and plant damage was low and did not seem to affect yield. Results indicate that reduced pesticide use enables indigenous natural enemies, particularly N.tenuis, to successfully control T. absoluta and prevent crop damage in open-field tomatoes.

  11. Landsat-based Earth Observations and Crowd-sourced Data Provide Near Real-time Monitoring of Chimpanzee Habitat

    Science.gov (United States)

    Nackoney, J.; Pintea, L.; Jantz, S.; Hansen, M.

    2015-12-01

    The endangered chimpanzee (Pan troglodytes) is threatened by habitat loss from resource extraction and land conversion, as well as hunting, disease and the illegal pet trade. It has been estimated that more than 70% of chimpanzee's tropical forest habitats in Africa are now threatened by land use change. Recent developments in remote sensing and cloud computing enable the use of satellite observations to provide a synoptic view of chimpanzee habitats at finer spatial and temporal resolutions that are locally relevant and consistent across the entire species' range. We present a practical Decision Support System to be used by the Jane Goodall Institute and partners to annually monitor and forecast chimpanzee habitat health in Africa. The system integrates Earth observations from 30-meter resolution Landsat data with a species-specific habitat model and a model forecasting future land use change, enhanced by crowd-sourced field data collected by local communities and rangers using the Open Data Kit app and Android mobile smartphones and tablets. While coarser-scale and static chimpanzee habitat models have been previously developed, this project is the first to develop a dynamic monitoring system updated annually via Earth observations data that will systematically monitor threats and changes in habitat over time. Since the chimpanzee is an important keystone, flagship and umbrella species, an annual chimpanzee habitat health index would support conservation goals of other species within its large 2.5 million sq. km range and could be an important indicator of overall ecosystem health of tropical forests in Africa.

  12. Hybrid Simulation of Supersonic Flow of Weakly Ionized Plasma along Open Field Magnetic Line Effect of Background Pressure

    Science.gov (United States)

    Laosunthara, Ampan; Akatsuka, Hiroshi

    2016-09-01

    In previous study, we experimentally examined physical properties of supersonic flow of weakly ionized expanding arc-jet plasma through an open magnetic field line (Bmax 0.16T). We found supersonic velocity of helium plasma up to Mach 3 and the space potential drop at the end of the magnets. To understand the plasma in numerical point of view, the flows of ion and neutral are treated by particle-based Direct Simulation Monte Carlo (DSMC) method, electron is treated as a fluid. The previous numerical study, we assumed 2 conditions. Ion and electron temperatures were the same (LTE condition). Ion and electron velocities were the same (current-free condition). We found that ion velocity decreased by collision with residual gas molecules (background pressure). We also found that space potential changing with background pressure. In other words, it was indicated that electric field exists and the current-free assumption is not proper. In this study, we add electron continuity and electron momentum equations to obtain electron velocity and space potential. We find that space potential changing with background pressure slightly. It is indicated that electron is essential to space potential formation than ion.

  13. Evolution of electric-field-induced quasibound states and resonances in one-dimensional open quantum systems

    CERN Document Server

    Olendski, O

    2016-01-01

    A comparative analysis of three different time-independent approaches to studying open quantum structures in uniform electric field $\\mathscr{E}$ was performed using the example of one-dimensional attractive or repulsive $\\delta$-potential and surface that supports the Robin boundary condition. The three considered methods exploit different properties of the scattering matrix $S(\\mathscr{E};E)$ as a function of energy $E$: its poles, real values, and zeros of the second derivative of its phase. The essential feature of the method of zeroing the resolvent, which produces complex energies, is the unlimited growth of the wave function at infinity, which is, however, eliminated by the time-dependent interpretation. The real energies at which the unitary scattering matrix becomes real correspond to the largest possible distortion, $S=+1$, or its absence at $S=-1$ which in either case leads to the formation of quasibound states. Depending on their response to increasing electric intensity, two types of field-induce...

  14. A NEW HABITAT CLASSIFICATION AND MANUAL FOR STANDARDIZED HABITAT MAPPING

    Directory of Open Access Journals (Sweden)

    J. BOLONI

    2007-04-01

    Full Text Available Today the documentation of natural heritage with scientific methods but for conservation practice – like mapping of actual vegetation – becomes more and more important. For this purpose mapping guides containing only the names and descriptions of vegetation types are not sufficient. Instead, new, mapping-oriented vegetation classification systems and handbooks are needed. There are different standardised systems fitted to the characteristics of a region already published and used successfully for surveying large territories. However, detailed documentation of the aims and steps of their elaboration is still missing. Here we present a habitat-classification method developed specifically for mapping and the steps of its development. Habitat categories and descriptions reflect site conditions, physiognomy and species composition as well. However, for species composition much lower role was given deliberately than in the phytosociological systems. Recognition and mapping of vegetation types in the field is highly supported by a definition, list of subtypes and list of ‘types not belonging to this habitat category’. Our system is two-dimensional: the first dimension is habitat type, the other is naturalness based habitat quality. The development of the system was conducted in two steps, over 200 mappers already tested it over 7000 field days in different projects.

  15. A NEW HABITAT CLASSIFICATION AND MANUAL FOR STANDARDIZED HABITAT MAPPING

    Directory of Open Access Journals (Sweden)

    A. KUN

    2007-01-01

    Full Text Available Today the documentation of natural heritage with scientific methods but for conservation practice – like mapping of actual vegetation – becomes more and more important. For this purpose mapping guides containing only the names and descriptions of vegetation types are not sufficient. Instead, new, mapping-oriented vegetation classification systems and handbooks are needed. There are different standardised systems fitted to the characteristics of a region already published and used successfully for surveying large territories. However, detailed documentation of the aims and steps of their elaboration is still missing. Here we present a habitat-classification method developed specifically for mapping and the steps of its development. Habitat categories and descriptions reflect site conditions, physiognomy and species composition as well. However, for species composition much lower role was given deliberately than in the phytosociological systems. Recognition and mapping of vegetation types in the field is highly supported by a definition, list of subtypes and list of ‘types not belonging to this habitat category’. Our system is two-dimensional: the first dimension is habitat type, the other is naturalness based habitat quality. The development of the system was conducted in two steps, over 200 mappers already tested it over 7000 field days in different projects.

  16. Open solar flux estimates from near-Earth measurements of the interplanetary magnetic field: comparison of the first two perihelion passes of the Ulysses spacecraft

    Directory of Open Access Journals (Sweden)

    M. Lockwood

    2004-04-01

    Full Text Available Results from all phases of the orbits of the Ulysses spacecraft have shown that the magnitude of the radial component of the heliospheric field is approximately independent of heliographic latitude. This result allows the use of near-Earth observations to compute the total open flux of the Sun. For example, using satellite observations of the interplanetary magnetic field, the average open solar flux was shown to have risen by 29% between 1963 and 1987 and using the aa geomagnetic index it was found to have doubled during the 20th century. It is therefore important to assess fully the accuracy of the result and to check that it applies to all phases of the solar cycle. The first perihelion pass of the Ulysses spacecraft was close to sunspot minimum, and recent data from the second perihelion pass show that the result also holds at solar maximum. The high level of correlation between the open flux derived from the various methods strongly supports the Ulysses discovery that the radial field component is independent of latitude. We show here that the errors introduced into open solar flux estimates by assuming that the heliospheric field's radial component is independent of latitude are similar for the two passes and are of order 25% for daily values, falling to 5% for averaging timescales of 27 days or greater. We compare here the results of four methods for estimating the open solar flux with results from the first and second perehelion passes by Ulysses. We find that the errors are lowest (1–5% for averages over the entire perehelion passes lasting near 320 days, for near-Earth methods, based on either interplanetary magnetic field observations or the aa geomagnetic activity index. The corresponding errors for the Solanki et al. (2000 model are of the order of 9–15% and for the PFSS method, based on solar magnetograms, are of the order of 13–47%. The model of Solanki et al. is based on the continuity equation of open flux, and uses

  17. Building a Habitat Conversion Model for San Francisco Bay Wetlands: A Multi-species Approach for Integrating GIS and Field Data

    Science.gov (United States)

    Diana Stralberg; Nils Warnock; Nadav Nur; Hildie Spautz; Gary W. Page

    2005-01-01

    More than 80 percent of San Francisco Bay's original tidal wetlands have been altered or displaced, reducing available habitat for a range of tidal marsh-dependent species, including the Federally listed California Clapper Rail (Rallus longirostris obsoletus) and three endemic Song Sparrow (Melospiza melodia) subspecies. In...

  18. Opening the Field

    DEFF Research Database (Denmark)

    Odgaard, Martin

    2012-01-01

    The perspective of this paper is to showcase the synergy that lies within a new urban-nature ecology framework. The aim is two-sided - on one side it is an exploration of how to work with landscape ecology in urban- and landscape design with a special emphasis on biodiver-sity. It is my claim...

  19. Anthropogenic areas as incidental substitutes for original habitat.

    Science.gov (United States)

    Martínez-Abraín, Alejandro; Jiménez, Juan

    2016-06-01

    One speaks of ecological substitutes when an introduced species performs, to some extent, the ecosystem function of an extirpated native species. We suggest that a similar case exists for habitats. Species evolve within ecosystems, but habitats can be destroyed or modified by natural and human-made causes. Sometimes habitat alteration forces animals to move to or remain in a suboptimal habitat type. In that case, the habitat is considered a refuge, and the species is called a refugee. Typically refugee species have lower population growth rates than in their original habitats. Human action may lead to the unintended generation of artificial or semiartificial habitat types that functionally resemble the essential features of the original habitat and thus allow a population growth rate of the same magnitude or higher than in the original habitat. We call such areas substitution habitats and define them as human-made habitats within the focal species range that by chance are partial substitutes for the species' original habitat. We call species occupying a substitution habitat adopted species. These are 2 new terms in conservation biology. Examples of substitution habitats are dams for European otters, wheat and rice fields for many steppeland and aquatic birds, and urban areas for storks, falcons, and swifts. Although substitution habitats can bring about increased resilience against the agents of global change, the conservation of original habitat types remains a conservation priority. © 2016 Society for Conservation Biology.

  20. Studies on breeding habitats and density of postembryonic immature filarial vector in a filarial endemic area

    Institute of Scientific and Technical Information of China (English)

    Manas Paramanik; Indranil Bhattacharjee; Goutam Chandra

    2012-01-01

    Objective: To obtain a complete and systematic data about the breeding habitats and density of vector immatures (larvae & pupae) in a filarial endemic area. Methods: All the possible permanent and temporary water bodies were surveyed systematically. Four hundred samples were taken in each season from each type of habitats. Sampling was done with a 250 mL dipper and immature mosquitoes were identified following standard keys. Results: In summer, rainy and winter seasons, overall 49.64%, 44.64%, and 28.57% of the habitats were positive for immature filarial vector (Culex quinquefasciatus) respectively; 36.93%, 35.11%, and 21.18%of the samples were positive for immatures respectively and overall per dip densities (PDD) of them were 10.29, 10.18, and 4.40 respectively. In the study year overall PDD were much higher in open cesspits (19.53) and drains (17.24) than in other habitats. Peak PDD of vector immatures in Dobas (ditches), open cesspits and drains were in March whereas in paddy fields and temporary water bodies peak PPD were in September. Conclusion: Dobas, paddy fields, open cesspits, drains, and temporary water bodies were found to be the main breeding sites of filarial vector, Cx. quinquefasciatus in different months. Open cesspits and drains were suitable almost throughout the year with peak in summer. Dobas also act as a steady breeding site throughout the year, whereas temporary water bodies immerge as strong breeding site during pre-monsoon and monsoon seasons. Information about the breeding habitats will be helpful to formulate a filarial vector control strategy and in turn to control the filarial diseases in the study area.

  1. Controlled progressive innate immune stimulation regimen prevents the induction of sickness behavior in the open field test

    Directory of Open Access Journals (Sweden)

    Chen Q

    2013-07-01

    Full Text Available Qun Chen, Andrew J Tarr, Xiaoyu Liu, Yufen Wang, Nathaniel S Reed, Cameron P DeMarsh, John F Sheridan, Ning QuanDivision of Oral Biology, Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USAAbstract: Peripheral immune activation by bacterial mimics or live replicating pathogens is well known to induce central nervous system activation. Sickness behavior alterations are often associated with inflammation-induced increases in peripheral proinflammatory cytokines (eg, interleukin [IL]-1β and IL-6. However, most researchers have used acute high dose endotoxin/bacterial challenges to observe these outcomes. Using this methodology may pose inherent risks in the translational interpretation of the experimental data in these studies. Studies using Escherichia coli have yet to establish the full kinetics of repeated E. coli peripheral injections. Therefore, we sought to examine the effects of repeated low dose E. coli on sickness behavior and local peripheral inflammation in the open field test. Results from the current experiments showed a behavioral dose response, where increased amounts of E. coli resulted in correspondingly increased sickness behavior. Furthermore, animals that received a subthreshold dose (ie, one that did not cause sickness behavior of E. coli 24 hours prior were able to withstand a larger dose of E. coli on the second day (a dose that would normally cause sickness behavior in mice without prior exposure without inducing sickness behavior. In addition, animals that received escalating subthreshold doses of E. coli on days 1 and 2 behaviorally tolerated a dose of E. coli 25 times higher than what would normally cause sickness behavior if given acutely. Lastly, increased levels of E. coli caused increased IL-6 and IL-1β protein expression in the peritoneal cavity, and this increase was blocked by administering a subthreshold dose of E. coli 24 hours prior. These data show that progressive

  2. IEEE Committee on Man and Radiation (COMAR) Technical Information Statement "exposure of medical personnel to electromagnetic fields from open magnetic resonance imaging systems".

    Science.gov (United States)

    Bassen, H; Schaefer, D J; Zaremba, L; Bushberg, J; Ziskin, M; Foster, K R

    2005-12-01

    Open magnetic resonance imaging (MRI) systems enable performing image-guided medical procedures for long periods of time very close to, or inside, the patient imaging area. Medical personnel can be exposed to relatively high static, gradient, and radiofrequency fields compared to most other MRI systems. The Committee on Man and Radiation of the Institute of Electrical and Electronics Engineers calculated or used existing data on magnetic flux densities and field strengths in or near the patient area to assess occupational exposure levels. Potential exposures to each field type were analyzed and compared to relevant values specified in international exposure limits including those of the Institute of Electrical and Electronics Engineers and the International Commission on Nonionizing Radiation Protection. Exposures of the head or torso of a worker to gradient fields near the center of the patient-imaging area can exceed most exposure limits even for times less than a second. Exposures to radiofrequency fields can exceed limits if sustained exposures (minutes or more) occur to parts of the body. Static magnetic fields used by present Open MRI systems are below exposure limits of all of the standards that address these fields. Overall results of this study suggest that manufacturers and others who program or operate Open MRI systems should take care to ensure that operating parameters produce exposures that comply with the relevant exposure limits. Also, since field levels fall off rapidly with increasing distance, user practices may be implemented that reduce exposures significantly.

  3. Open source software for electric field Monte Carlo simulation of coherent backscattering in biological media containing birefringence.

    Science.gov (United States)

    Radosevich, Andrew J; Rogers, Jeremy D; Capoğlu, Ilker R; Mutyal, Nikhil N; Pradhan, Prabhakar; Backman, Vadim

    2012-11-01

    ABSTRACT. We present an open source electric field tracking Monte Carlo program to model backscattering in biological media containing birefringence, with computation of the coherent backscattering phenomenon as an example. These simulations enable the modeling of tissue scattering as a statistically homogeneous continuous random media under the Whittle-Matérn model, which includes the Henyey-Greenstein phase function as a special case, or as a composition of discrete spherical scatterers under Mie theory. The calculation of the amplitude scattering matrix for the above two cases as well as the implementation of birefringence using the Jones N-matrix formalism is presented. For ease of operator use and data processing, our simulation incorporates a graphical user interface written in MATLAB to interact with the underlying C code. Additionally, an increase in computational speed is achieved through implementation of message passing interface and the semi-analytical approach. Finally, we provide demonstrations of the results of our simulation for purely scattering media and scattering media containing linear birefringence.

  4. Imaging sequences for intraoperative MR-guided laparoscopic liver resection in 1.0-T high field open MRI

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, S.S.; Schmidt, S.C.; Schumacher, G. [University Medicine Berlin, Department of General, Visceral and Transplantation Surgery, Charite Campus Virchow Clinic, Berlin (Germany); Rump, J.; Streitparth, F.; Teichgraeber, U. [University Medicine Berlin, Department of Radiology, Charite Campus Mitte, Berlin (Germany); Seebauer, C. [University Medicine Berlin, Department of Trauma Surgery, Charite Campus Virchow Clinic, Berlin (Germany); Voort, I.V. der [University Medicine Berlin, Department of Gastroenterology, Charite Campus Virchow Clinic, Berlin (Germany)

    2009-09-15

    The aim of this study was to identify suitable interactive (dynamic) magnetic resonance (MR) sequences for real-time MR-guided liver dissection in a 1.0-T high field open MRI system. Four dynamic sequences encompassing balanced steady state free precession (bSSFP), T1W gradient echo (GRE), T2W GRE and T2W fast spin echo (FSE) were analysed regarding the image quality, artefact susceptibility and the performance of SNR and CNR. The T2W FSE sequence (1.5 s/image) was considered superior because of an intraoperative SNR of 6.9 ({+-}0.7) and CNR (vessel to parenchyma) of 5.6 ({+-}1.7) in the interventional setting. As a proof of concept, MR-guided laparoscopic liver resection was performed in two healthy domestic pigs by using the T2W FSE sequence. The additional MR images offered simultaneous multiplanar real-time visualisation of the liver vessels during the intervention and thereby increased the anatomical orientation of the surgeon. (orig.)

  5. Effect of light-dark changes on the locomotor activity in open field in adult rats and opossums.

    Science.gov (United States)

    Klejbor, I; Ludkiewicz, B; Turlejski, K

    2013-11-01

    There have been no reports on how the light-dark changes determine the locomotor activity of animals in the group of high reactivity (HR) and low reactivity (LR). In the present study we have compared selected parameters of the locomotor activity of the HR and the LR groups of the laboratory opossums and Wistar rats during consecutive, light and dark phases in the open field test. Sixty male Wistar adult rats, at an average weight of 350 g each, and 24 adult Monodelphis opossums of both sexes at an average weight of 120 g each were used. The animals' activity for 2 h daily between the hours of 17:30 and 19:30, in line with the natural light-dark cycle were recorded and then analysed using VideoTrack ver.2.0 (Vievpoint France). According to our results, we noted that a change of the experimental conditions from light to dark involves an increase in the locomotor activity in rats and opossums of the HR group, while there is no effect on the activity of the rats and opossums in the LR group. Locomotor activity in the HR rats, both in the light and dark conditions is characterised by a consistent pattern of change - higher activity in the first stage of the recording and a slowdown (habituation) in the second phase of the observation. The locomotor activity of the opossum, during both light and dark conditions, was observed to be at a consistently high level compared to the rats.

  6. Guidelines for Setting Up an Extended Field Trip to Florida and the Florida Keys: An Interactive Experiential Training Field Biology Program Consisting of Pretrip Instruction, Search Image Training, Field Exercises, and Observations of Tropical Habitats and Coral Reefs.

    Science.gov (United States)

    Baker, Claude D.; And Others

    The importance of experiential aspects of biological study is addressed using multi-dimensional classroom and field classroom approaches to student learning. This document includes a guide to setting up this style of field experience. Several teaching innovations are employed to introduce undergraduate students to the literature, techniques, and…

  7. Free-living bacterial communities associated with tubeworm (Ridgeia piscesae) aggregations in contrasting diffuse flow hydrothermal vent habitats at the Main Endeavour Field, Juan de Fuca Ridge.

    Science.gov (United States)

    Forget, Nathalie L; Kim Juniper, S

    2013-04-01

    We systematically studied free-living bacterial diversity within aggregations of the vestimentiferan tubeworm Ridgeia piscesae sampled from two contrasting flow regimes (High Flow and Low Flow) in the Endeavour Hydrothermal Vents Marine Protected Area (MPA) on the Juan de Fuca Ridge (Northeast Pacific). Eight samples of particulate detritus were recovered from paired tubeworm grabs from four vent sites. Most sequences (454 tag and Sanger methods) were affiliated to the Epsilonproteobacteria, and the sulfur-oxidizing genus Sulfurovum was dominant in all samples. Gammaproteobacteria were also detected, mainly in Low Flow sequence libraries, and were affiliated with known methanotrophs and decomposers. The cooccurrence of sulfur reducers from the Deltaproteobacteria and the Epsilonproteobacteria suggests internal sulfur cycling within these habitats. Other phyla detected included Bacteroidetes, Actinobacteria, Chloroflexi, Firmicutes, Planctomycetes, Verrucomicrobia, and Deinococcus-Thermus. Statistically significant relationships between sequence library composition and habitat type suggest a predictable pattern for High Flow and Low Flow environments. Most sequences significantly more represented in High Flow libraries were related to sulfur and hydrogen oxidizers, while mainly heterotrophic groups were more represented in Low Flow libraries. Differences in temperature, available energy for metabolism, and stability between High Flow and Low Flow habitats potentially explain their distinct bacterial communities.

  8. [Does open access publishing increase the impact of scientific articles? An empirical study in the field of intensive care medicine].

    Science.gov (United States)

    Riera, M; Aibar, E

    2013-05-01

    Some studies suggest that open access articles are more often cited than non-open access articles. However, the relationship between open access and citations count in a discipline such as intensive care medicine has not been studied to date. The present article analyzes the effect of open access publishing of scientific articles in intensive care medicine journals in terms of citations count. We evaluated a total of 161 articles (76% being non-open access articles) published in Intensive Care Medicine in the year 2008. Citation data were compared between the two groups up until April 30, 2011. Potentially confounding variables for citation counts were adjusted for in a linear multiple regression model. The median number (interquartile range) of citations of non-open access articles was 8 (4-12) versus 9 (6-18) in the case of open access articles (p=0.084). In the highest citation range (>8), the citation count was 13 (10-16) and 18 (13-21) (p=0.008), respectively. The mean follow-up was 37.5 ± 3 months in both groups. In the 30-35 months after publication, the average number (mean ± standard deviation) of citations per article per month of non-open access articles was 0.28 ± 0.6 versus 0.38 ± 0.7 in the case of open access articles (p=0.043). Independent factors for citation advantage were the Hirsch index of the first signing author (β=0.207; p=0.015) and open access status (β=3.618; p=0.006). Open access publishing and the Hirsch index of the first signing author increase the impact of scientific articles. The open access advantage is greater for the more highly cited articles, and appears in the 30-35 months after publication. Copyright © 2012 Elsevier España, S.L. and SEMICYUC. All rights reserved.

  9. Lidar: shedding new light on habitat characterization and modeling.

    Science.gov (United States)

    Kerri T. Vierling; Lee A. Vierling; William A. Gould; Sebastian Martinuzzi; Rick M. Clawges

    2008-01-01

    Ecologists need data on animal–habitat associations in terrestrial and aquatic environments to design and implement effective conservation strategies. Habitat characteristics used in models typically incorporate (1) field data of limited spatial extent and/or (2) remote sensing data that do not characterize the vertical habitat structure. Remote sensing tools that...

  10. Foraging behavior related to habitat characteristics in the invasive wasp Vespula germanica

    Institute of Scientific and Technical Information of China (English)

    PAOLA D'ADAMO; MARIANA LOZADA

    2007-01-01

    the feeding site until depleting the resource. In the present study we analyzed how environmental cues affect wasps' behavior when re-locating a protein food source. We studied this behavior in two different natural habitats: closed and open habitats.As closed habitats have more references to orient wasps to the feeding site than open habitats,we hypothesized that they would return to the foraging site more frequently in closed habitats than in open ones. We tested this hypothesis by studying wasp behavior in three different natural habitat conditions: (i) closed habitats, (ii) open habitats, and (iii) open habitats artificially modified by adding five sticks with flagging. Experiments consisted of training individual wasps to feed from a certain array, and at the testing phase we removed food and displaced the array by 60 cm. Therefore, we recorded wasps' choices when returning to the training area, by counting both the wasps' first approaches and the number of visits to the original feeding site and the displaced array. Wasps' behavior while re-locating a protein food source was different if foraging at open or closed habitats. Wasps more frequently revisited a previous feeding location when foraging in closed habitats than when foraging in open ones. Furthermore, wasps more frequently visited the displaced array than the original feeding site in all three treatments. Nevertheless, when wasps were trained in closed habitats,they returned to the original feeding site more frequently than if trained in open ones.Interestingly, when five sticks with flagging were added in open habitats, wasps responded similarly as in closed habitats without these references. The results show that foraging behavior in V. germanica seems to be different in closed and open habitats, probably associated with the existence of references that guide foragers when re-locating undepleted resources.

  11. Long-term changes in open field behaviour following a single social defeat in rats can be reversed by sleep deprivation

    NARCIS (Netherlands)

    Meerlo, P; Overkamp, GJF; Benning, MA; Koolhaas, JM; vandenHoofdakker, RH

    1996-01-01

    The long-term consequences of a single social defeat on open field behaviour in rats were studied, with special emphasis on the time course of stress-induced changes. Animals were subjected to social defeat by placing them into the territory of an aggressive male conspecific for 1 h. After the defea

  12. Effects of phenazepam on the behavior of C57BL/6 and BALB/c mice in the open field test after naloxone pretreatment.

    Science.gov (United States)

    Seredenin, S B; Nadorova, A V; Kolik, L G; Yarkova, M A

    2013-07-01

    We studied the effects of phenazepam (0.075 mg/kg) after pretreatment (5 minutes before) with naloxone (10 mg/kg) on open-field behavior of C57Bl/6 and BALB/c mice. In ex vivo experiments, we studied the effects of naloxone (1 and 10 mg/kg) on receptor binding of [(3)H]-flunitrazepam by membranes of brain fraction (P1+P2) of C57Bl/6 and BALB/c mice. It was shown that naloxone increased motor activity in the open field in BALB/c mice and decreased this parameter in C57Bl/6 mice. During combined treatment, naloxone potentiated the activating effects of phenazepam on the open-field behavior of BALB/c mice and slightly increased the sedative effect of this drug in C57Bl/6 mice. Naloxone stimulated reception of [(3)H]-flunitrazepam in BALB/c mice and slightly increased radioligand binding in C57Bl/6 mice. These data attest to enhanced reception in benzodiazepine site of GABAA-receptor under conditions of opioid receptor blockade, the presence of anxiolytic or sedative (depending on the phenotype of the response to emotional stress) effect of naloxone, and co-directed effects of naloxone and benzodiazepine tranquilizer on open-field behavior of C57Bl/6 and BALB/c mice.

  13. Open Field Test; Technical Report 14. Disadvantaged Children and Their First School Experiences. ETS-Head Start Longitudinal Study. Technical Report Series.

    Science.gov (United States)

    Ward, William C.

    The Open Field Test was used to assess variables that might not be manifested in a more standard testing situation. In this test, the child was shown 10 standard play objects in the room, and was told to do anything he wished with the toys. The tester initiated no interaction with the child and responded minimally to any overture made by the…

  14. Habitat selection by postbreeding female diving ducks: Influence of habitat attributes and conspecifics

    Science.gov (United States)

    Austin, Jane E.; O'Neil, Shawn T.; Warren, Jeffrey M.

    2017-01-01

    Habitat selection studies of postbreeding waterfowl have rarely focused on within-wetland attributes such as water depth, escape cover, and food availability. Flightless waterfowl must balance habitat selection between avoiding predation risks and feeding. Reproductively successful female ducks face the greatest challenges because they begin the definitive prebasic molt at or near the end of brood rearing, when their body condition is at a low point. We assessed the relative importance of habitat attributes and group effects in habitat selection by postbreeding female lesser scaup Aythya affinis on a 2332-ha montane wetland complex during the peak flightless period (August) over seven years. Hypothesis-based habitat attributes included percent open water, open water:emergent edge density, water depth, percent flooded bare substrate, fetch (distance wind can travel unobstructed), group size, and several interactions representing functional responses to interannual variation in water levels. Surveys of uniquely marked females were conducted within randomly ordered survey blocks. We fitted two-part generalized linear mixed-effects models to counts of marked females within survey blocks, which allowed us to relate habitat attributes to relative probability of occurrence and, given the presence of a marked female, abundance of marked individuals. Postbreeding female scaup selected areas with water depths > 40 cm, large open areas, and intermediate edge densities but showed no relation to flooded bare substrate, suggesting their habitat preferences were more influenced by avoiding predation risks and disturbances than in meeting foraging needs. Grouping behavior by postbreeding scaup suggests habitat selection is influenced in part by behavioral components and/or social information, conferring energetic and survival benefits (predation and disturbance risks) but potentially also contributing to competition for food resources. This study demonstrates the importance of

  15. Habitat monitoring plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Management of habitat is required in order to achieve the refuge purpose and wildlife objectives. The Upland Habitat Management Plan (1993, Interim Plan) and the...

  16. EcologicHabitat_WCV

    Data.gov (United States)

    Vermont Center for Geographic Information — WCV describes the value of the Wildlife Habitat Suitability as it approaches the state highway system. This analysis was designed to use the Wildlife Habitat...

  17. California Condor Critical Habitat

    Data.gov (United States)

    California Department of Resources — These Data identify (in general) the areas where critical habitat for the California Condor occur. Critical habitat for the species consists of the following 10...

  18. Predictive Seagrass Habitat Model

    Science.gov (United States)

    Restoration of ecosystem services provided by seagrass habitats in estuaries requires a firm understanding of the modes of action of multiple interacting stressors including nutrients, climate change, coastal land-use change, and habitat modification. We explored the application...

  19. Relationships between early experience to dietary diversity, acceptance of novel flavors, and open field behavior in sheep.

    Science.gov (United States)

    Villalba, Juan J; Catanese, Francisco; Provenza, Frederick D; Distel, Roberto A

    2012-01-18

    This study determined whether early experiences by sheep to monotonous or diverse diets influence: (1) plasmatic profiles of cortisol, a hormone involved in stress responses by mammals, before and after an ACTH challenge, (2) the readiness to eat new foods in a new environment, (3) general fearfulness and response to separation--as measured by the open field test (OFT) and stress induced hyperthermia (SIH)--and (4) the link between (2) and (3). Thirty, 2-mo-old lambs were randomly assigned to 3 treatments (10 lambs/treatment). Lambs in one treatment (Diversity--DV) received in successive periods of exposure all possible 4-way choice combinations of 2 foods high in energy and 2 foods high in protein from an array of 6 foods: 3 high in energy (beet pulp, oat grain, and a mix of grape pomace:milo [40:60]) and 3 high in protein (soybean meal, alfalfa, corn gluten meal). Lambs in another treatment (DV+T) received the same exposure described for DV but two phytochemicals, oxalic acid (1.5%) and quebracho tannins (10%) were randomly added within any period of exposure to foods high in energy or to foods high in protein. Lambs in the third treatment (Monotony--MO) received a monotonous balanced ration containing all 6 foods fed to the other groups. After exposure, lambs were offered a choice of the aforementioned 6 foods (DV; DV+T) or the monotonous diet (MO). Lambs were intravenously injected with ACTH 1 h after food presentation, and sampled at 1, 2, and 3 h post feeding for determinations of plasma cortisol concentrations. Reluctance to eat novel flavored foods (onion-, coconut- and cinnamon-flavored wheat bran), open field behavior, and SIH was assessed in all treatments. Lambs in MO showed greater concentrations of plasma cortisol 1 h after food presentation than lambs in the DV or DV+T treatments (P=0.04). However, the difference was small and no differences among treatments were detected after an ACTH challenge (P>0.1). Lambs in DV consumed more onion-flavored wheat

  20. Hyperspectral remote sensing of crop leaf chlorophyll content using reflectance simulation model and field data in open canopies

    Science.gov (United States)

    Jiao, Quanjun; Wu, Yanhong; Liu, Liangyun; Zhang, Bing

    2015-04-01

    Leaf chlorophyll content -a and -b content (Cab) is an indicator for crop nutrition status and photosynthetic capacity. Remote sensing of Cab plays an important role in crop growth monitoring, pest and disease diagnosis, and crop yield assessment, yet the feasibility and stability of such estimation has not been assessed thoroughly for mixed pixels when crop canopies are not closed. This study analyzes the influence of spectral mixing on leaf chlorophyll content estimation using canopy spectra simulated by the PROSAIL reflectance model and the spectral linear mixture concept. It is observed that the accuracy of leaf chlorophyll content estimation would be degraded for mixed pixels using the well accepted approach of the combination of TCARI and OSAVI. A two-step method was thus developed for winter wheat chlorophyll content estimation by taking into consideration the fractional vegetation cover using a look-up table approach. The two methods were validated using ground spectra, airborne hyperspectral data and leaf chlorophyll content measured the same time over experimental winter wheat fields. Using the two-step method, the leaf chlorophyll content of the open canopy was estimated from the airborne hyperspectral imagery with a root mean square error of 5.18 μg cm-2, which is an improvement of about 8.9% relative to the accuracy obtained using the TCARI/OSAVI ratio directly. This implies that the method proposed in this study has great potential for hyperspectral applications in agricultural management, particularly for applications before crop canopy closure. This study, therefore, offers a feasible technique that might be applied to crop chlorophyll content estimation using large-scale remote sensing data.

  1. Assessment of exposure to pesticides during mixing/loading and spraying of tomatoes in the open field.

    Science.gov (United States)

    Aprea, Maria Cristina; Bosi, Anna; Manara, Michele; Mazzocchi, Barbara; Pompini, Alessandra; Sormani, Francesca; Lunghini, Liana; Sciarra, Gianfranco

    2016-01-01

    Some evidence of exposure-response of metolachlor and pendimethalin for lung cancer and an association of metribuzin with risk of glioma have been reported. The primary objectives in this study were to evaluate exposure and occupational risk during mixing/loading of pesticides and during their application to tomatoes cultivated in open fields. Sixteen farmers were sampled. Respiratory exposure was estimated by personal air sampling using fiberglass filters in a IOM device. Dermal exposure was assessed using skin pads and hand washing. Absorbed doses were estimated assuming 100% lung retention, and 50% or 10% skin absorption for metribuzin, and pendimethalin and metolachlor, respectively. The three pesticides were quantified by gas chromatography tandem mass spectrometry in all matrices. Metolachlor was used as a tracer of contamination of clothes and tractors unrelated to the exposure monitored. Respiratory exposure to metribuzin, used in granular form, was on average more than one order of magnitude higher than exposure to pendimethalin, used in the form of microencapsulated liquid. The actual doses were 0.067-8.08 µg/kg bw, 0.420-12.6 µg/kg bw, and 0.003-0.877 µg/kg bw for pendimethalin, metribuzin, and metolachlor, respectively. Dermal exposure was about 88% of the actual dose for metribuzin and more than 95%, for pendimethalin and metolachlor. For risk assessment, the total absorbed doses (sum of respiratory and skin absorbed doses) were compared with the AOEL for each compound. The actual and absorbed doses of the three pesticides were always lower than the acceptable operator exposure level (AOEL), which are reported to be 234 µg/kg bw, 20 µg/kg bw, and 150 µg/kg bw for pendimethalin, metribuzin, and metolachlor, respectively. In any case, personal protective equipment and spraying devices should be chosen with care to minimize exposure.

  2. Prototypical anxiolytics do not reduce anxiety-like behavior in the open field in C57BL/6J mice.

    Science.gov (United States)

    Thompson, Trey; Grabowski-Boase, Laura; Tarantino, Lisa M

    2015-06-01

    Understanding and effectively treating anxiety disorders are a challenge for both scientists and clinicians. Despite a variety of available therapies, the efficacy of current treatments is still not optimal and adverse side effects can result in non-compliance. Animal models have been useful for studying the underlying biology of anxiety and assessing the anxiolytic properties of potential therapeutics. The open field (OF) is a commonly used assay of anxiety-like behavior. The OF was developed and validated in rats and then transferred to use in the mouse with only limited validation. The present study tests the efficacy of prototypical benzodiazepine anxiolytics, chlordiazepoxide (CDP) and diazepam (DZ), for increasing center time in the OF in C57BL/6J (B6) mice. Multiple doses of CDP and DZ did not change time spent in the center of the OF. Increasing illumination in the OF did not alter these results. The non-benzodiazepine anxiolytic, buspirone (BUSP) also failed to increase center time in the OF while the anxiogenic meta-chlorophenylpiperazine (mCPP) increased center time. Additional inbred mouse strains, BALB/cJ (BALB) and DBA/2J (D2) did not show any change in center time in response to CDP. Moreover, evaluation of CDP in B6 mice in the elevated plus maze (EPM), elevated zero maze (EZM) and light dark assay (LD) did not reveal changes in anxiety-like behavior while stress-induced hyperthermia (SIH) was decreased by DZ. Pharmacokinetic (PK) studies suggest that adequate CDP is present to induce anxiolysis. We conclude that the measure of center time in the OF does not show predictive validity for anxiolysis in these inbred mouse strains.

  3. A global wave-driven magnetohydrodynamic solar model with a unified treatment of open and closed magnetic field topologies

    Energy Technology Data Exchange (ETDEWEB)

    Oran, R.; Van der Holst, B.; Landi, E.; Jin, M.; Sokolov, I. V.; Gombosi, T. I., E-mail: oran@umich.edu [Atmospheric, Oceanic and Atmospheric Sciences, University of Michigan, 2455 Hayward, Ann Arbor, MI, 48105 (United States)

    2013-12-01

    We describe, analyze, and validate the recently developed Alfvén Wave Solar Model, a three-dimensional global model starting from the top of the chromosphere and extending into interplanetary space (out to 1-2 AU). This model solves the extended, two-temperature magnetohydrodynamics equations coupled to a wave kinetic equation for low-frequency Alfvén waves. In this picture, heating and acceleration of the plasma are due to wave dissipation and to wave pressure gradients, respectively. The dissipation process is described by a fully developed turbulent cascade of counterpropagating waves. We adopt a unified approach for calculating the wave dissipation in both open and closed magnetic field lines, allowing for a self-consistent treatment in any magnetic topology. Wave dissipation is the only heating mechanism assumed in the model; no geometric heating functions are invoked. Electron heat conduction and radiative cooling are also included. We demonstrate that the large-scale, steady state (in the corotating frame) properties of the solar environment are reproduced, using three adjustable parameters: the Poynting flux of chromospheric Alfvén waves, the perpendicular correlation length of the turbulence, and a pseudoreflection coefficient. We compare model results for Carrington rotation 2063 (2007 November-December) with remote observations in the extreme-ultraviolet and X-ray ranges from the Solar Terrestrial Relations Observatory, Solar and Heliospheric Observatory, and Hinode spacecraft and with in situ measurements by Ulysses. The results are in good agreement with observations. This is the first global simulation that is simultaneously consistent with observations of both the thermal structure of the lower corona and the wind structure beyond Earth's orbit.

  4. Magnetic resonance imaging: Clinical experience with an open low-field-strength scanner in a resource challenged African state

    Directory of Open Access Journals (Sweden)

    G I Ogbole

    2012-01-01

    Full Text Available Introduction: Despite the fact that an magnetic resonance imaging (MRI has been in clinical use for over 20 years, its use and availability in Nigeria, a West African state, is still extremely low. Hence, only few publications are available on the clinical experience with MRI from Nigeria. We set out to evaluate our initial clinical experience with a low-field-strength MRI in a Nigeria′s foremost university hospital. Materials and Methods: A retrospective review of all studies, performed with an open 0.2 Tesla MAGNETOM Concerto (Siemens Medical MRI scanner over a 5-year period (2006 - 2010 was conducted. All patients with complete records were evaluated for their clinical and demographic characteristics. Results: The records of 799 MRI studies were available. Patients′ ages ranged from 1 day to 90 years, with a mean of 40.1 years (± 20.7 SD. There were 463 (57.9% males and 336 (42.1% females. Over 90% of the studies were requested to evaluate brain or spine lesions. Low back pain represented the commonest (161/799, 20.7% clinical indication for MRI. The largest number of patients was referred by physicians from surgical specialties (65.6%. Conclusion: The awareness and competence for proper use of MRI in Nigeria appears high. Low back pain is the commonest indication for MRI in our institution, and surgeons make a greater use of the facility. The provision of high-signal strength MRI may be beneficial in making a wider range of applications available to clinicians.

  5. Controlled progressive innate immune stimulation regimen prevents the induction of sickness behavior in the open field test.

    Science.gov (United States)

    Chen, Qun; Tarr, Andrew J; Liu, Xiaoyu; Wang, Yufen; Reed, Nathaniel S; Demarsh, Cameron P; Sheridan, John F; Quan, Ning

    2013-01-01

    Peripheral immune activation by bacterial mimics or live replicating pathogens is well known to induce central nervous system activation. Sickness behavior alterations are often associated with inflammation-induced increases in peripheral proinflammatory cytokines (eg, interleukin [IL]-1β and IL-6). However, most researchers have used acute high dose endotoxin/bacterial challenges to observe these outcomes. Using this methodology may pose inherent risks in the translational interpretation of the experimental data in these studies. Studies using Escherichia coli have yet to establish the full kinetics of repeated E. coli peripheral injections. Therefore, we sought to examine the effects of repeated low dose E. coli on sickness behavior and local peripheral inflammation in the open field test. Results from the current experiments showed a behavioral dose response, where increased amounts of E. coli resulted in correspondingly increased sickness behavior. Furthermore, animals that received a subthreshold dose (ie, one that did not cause sickness behavior) of E. coli 24 hours prior were able to withstand a larger dose of E. coli on the second day (a dose that would normally cause sickness behavior in mice without prior exposure) without inducing sickness behavior. In addition, animals that received escalating subthreshold doses of E. coli on days 1 and 2 behaviorally tolerated a dose of E. coli 25 times higher than what would normally cause sickness behavior if given acutely. Lastly, increased levels of E. coli caused increased IL-6 and IL-1β protein expression in the peritoneal cavity, and this increase was blocked by administering a subthreshold dose of E. coli 24 hours prior. These data show that progressive challenges with subthreshold levels of E. coli may obviate the induction of sickness behavior and proinflammatory cytokine expression.

  6. The Effects of Endogenous Mycorrhiza (Glomus spp. on Stand Establishment Rate and Yield of Open Field Tomato Crop

    Directory of Open Access Journals (Sweden)

    ANGJELINA VUKSANI

    2015-03-01

    Full Text Available Graded seeds of a tomato commercial cultivar (Suta F1 were sown in plugged (30 cm3 foam trays filled with vermiculate. For the half of seeds the substrate was homogenously mixed (10% vol/vol with broken expanded clay biologically activated by immobilized propagules of naturally occurring AM-fungi (Glomus intradadices, Glomus etunicatum, Glomus mosseae, Glomus geosporum, Glomus clarum, supplied by BioSym B.V. For the next half, it was homogenously mixed with free clay particles of the same size with the previous one (10% vol/vol. Thirty days after sowing, tomato seedlings were transplanted in to 200 cm3 plastic pots filled with vermiculite. Either AMF non pre inoculated seedlings (non AMF, or AMF pre inoculated (AMF, were equally divided in three subgroups based on the level of salinity applied in the nutrient solution (0, 50 and 100 mM sodium chlorate. On the day of transplanting and 7 days after transplanting, 10 plants were randomly selected for each experimental plot. For each of them, the dry weight of root (RW, leaf (LA, steam (SW and the whole plant (W was determined and based on that, the relative growth rates (RGR and root relative growth rate (RRGR were calculated and used as the parameters assessing the stand establishment rate of tomato seedlings after transplanting. Additionally, stomata conductance and leaf temperature were measured to assess AMF effects on physiological performance of transplanted seedlings. In order to assess the effect of AM fungi pre inoculation on total yield, parallel with pot transplanting, a field experiment was conducted according to a three replication randomized block design. It was proved that the production of open field tomato can be enhanced by the pre inoculation of AM fungi to tomato transplants at the nursery stage. Due to the pre inoculation of AM fungi, the tomato seedlings can subsequently benefit a faster stand establishment rate and higher vigor which is further reflected to a prolonged

  7. SMILI?: A Framework for Interfaces to Learning Data in Open Learner Models, Learning Analytics and Related Fields

    Science.gov (United States)

    Bull, Susan; Kay, Judy

    2016-01-01

    The SMILI? (Student Models that Invite the Learner In) Open Learner Model Framework was created to provide a coherent picture of the many and diverse forms of Open Learner Models (OLMs). The aim was for SMILI? to provide researchers with a systematic way to describe, compare and critique OLMs. We expected it to highlight those areas where there…

  8. Living in a caatinga-rocky field transitional habitat: ecological aspects of the whiptail lizard Cnemidophorus ocellifer (Teiidae) in northeastern Brazil

    OpenAIRE

    Vanderlaine A Menezes; Monique Van Sluys; Angélica F. Fontes; Carlos F. D Rocha

    2011-01-01

    The ecology of the active forager lizard Cnemidophorus ocellifer (Spix, 1825) was studied to analyze food habits, thermal ecology and habitat use, in the Morro do Chapéu municipality (11º29'S, 41º07'W), state of Bahia, Brazil. Lizards (N = 34) were collected with rubber bands or with an air rifle and, for each individual, we recorded cloacal temperature (Tc), air temperature (Ta) (1 cm above the substrate) and substrate temperature (Ts) (to nearest 0.2ºC). We registered the microhabitat used ...

  9. 3D for the people: multi-camera motion capture in the field with consumer-grade cameras and open source software

    Directory of Open Access Journals (Sweden)

    Brandon E. Jackson

    2016-09-01

    Full Text Available Ecological, behavioral and biomechanical studies often need to quantify animal movement and behavior in three dimensions. In laboratory studies, a common tool to accomplish these measurements is the use of multiple, calibrated high-speed cameras. Until very recently, the complexity, weight and cost of such cameras have made their deployment in field situations risky; furthermore, such cameras are not affordable to many researchers. Here, we show how inexpensive, consumer-grade cameras can adequately accomplish these measurements both within the laboratory and in the field. Combined with our methods and open source software, the availability of inexpensive, portable and rugged cameras will open up new areas of biological study by providing precise 3D tracking and quantification of animal and human movement to researchers in a wide variety of field and laboratory contexts.

  10. 3D for the people: multi-camera motion capture in the field with consumer-grade cameras and open source software.

    Science.gov (United States)

    Jackson, Brandon E; Evangelista, Dennis J; Ray, Dylan D; Hedrick, Tyson L

    2016-09-15

    Ecological, behavioral and biomechanical studies often need to quantify animal movement and behavior in three dimensions. In laboratory studies, a common tool to accomplish these measurements is the use of multiple, calibrated high-speed cameras. Until very recently, the complexity, weight and cost of such cameras have made their deployment in field situations risky; furthermore, such cameras are not affordable to many researchers. Here, we show how inexpensive, consumer-grade cameras can adequately accomplish these measurements both within the laboratory and in the field. Combined with our methods and open source software, the availability of inexpensive, portable and rugged cameras will open up new areas of biological study by providing precise 3D tracking and quantification of animal and human movement to researchers in a wide variety of field and laboratory contexts.

  11. Dose-response effects of systemic anandamide administration in mice sequentially submitted to the open field and elevated plus-maze tests

    Directory of Open Access Journals (Sweden)

    A. Ribeiro

    2009-06-01

    Full Text Available The endocannabinoid system is involved in the control of many physiological functions, including the control of emotional states. In rodents, previous exposure to an open field increases the anxiety-like behavior in the elevated plus-maze. Anxiolytic-like effects of pharmacological compounds that increase endocannabinoid levels have been well documented. However, these effects are more evident in animals with high anxiety levels. Several studies have described characteristic inverted U-shaped dose-response effects of drugs that modulate the endocannabinoid levels. However, there are no studies showing the effects of different doses of exogenous anandamide, an endocannabinoid, in animal models of anxiety. Thus, in the present study, we determined the dose-response effects of exogenous anandamide at doses of 0.01, 0.1, and 1.0 mg/kg in C57BL/6 mice (N = 10/group sequentially submitted to the open field and elevated plus-maze. Anandamide was diluted in 0.9% saline, ethyl alcohol, Emulphor® (18:1:1 and administered ip (0.1 mL/10 g body weight; control animals received the same volume of anandamide vehicle. Anandamide at the dose of 0.1 mg/kg (but not of 0.01 or 1 mg/kg increased (P < 0.05 the time spent and the distance covered in the central zone of the open field, as well as the exploration of the open arms of the elevated plus-maze. Thus, exogenous anandamide, like pharmacological compounds that increase endocannabinoid levels, promoted a characteristic inverted U-shaped dose-response effect in animal models of anxiety. Furthermore, anandamide (0.1 mg/kg induced an anxiolytic-like effect in the elevated plus-maze (P < 0.05 after exposing the animals to the open field test.

  12. Dose-response effects of systemic anandamide administration in mice sequentially submitted to the open field and elevated plus-maze tests.

    Science.gov (United States)

    Ribeiro, A; Ferraz-de-Paula, V; Pinheiro, M L; Palermo-Neto, J

    2009-06-01

    The endocannabinoid system is involved in the control of many physiological functions, including the control of emotional states. In rodents, previous exposure to an open field increases the anxiety-like behavior in the elevated plus-maze. Anxiolytic-like effects of pharmacological compounds that increase endocannabinoid levels have been well documented. However, these effects are more evident in animals with high anxiety levels. Several studies have described characteristic inverted U-shaped dose-response effects of drugs that modulate the endocannabinoid levels. However, there are no studies showing the effects of different doses of exogenous anandamide, an endocannabinoid, in animal models of anxiety. Thus, in the present study, we determined the dose-response effects of exogenous anandamide at doses of 0.01, 0.1, and 1.0 mg/kg in C57BL/6 mice (N = 10/group) sequentially submitted to the open field and elevated plus-maze. Anandamide was diluted in 0.9% saline, ethyl alcohol, Emulphor (18:1:1) and administered ip (0.1 mL/10 g body weight); control animals received the same volume of anandamide vehicle. Anandamide at the dose of 0.1 mg/kg (but not of 0.01 or 1 mg/kg) increased (P open field, as well as the exploration of the open arms of the elevated plus-maze. Thus, exogenous anandamide, like pharmacological compounds that increase endocannabinoid levels, promoted a characteristic inverted U-shaped dose-response effect in animal models of anxiety. Furthermore, anandamide (0.1 mg/kg) induced an anxiolytic-like effect in the elevated plus-maze (P open field test.

  13. 基于OpenMP的电磁场FDTD多核并行程序设计%Design of electromagnetic field FDTD multi-core parallel program based on OpenMP

    Institute of Scientific and Technical Information of China (English)

    吕忠亭; 张玉强; 崔巍

    2013-01-01

    探讨了基于OpenMP的电磁场FDTD多核并行程序设计的方法,以期实现该方法在更复杂的算法中应用具有更理想的性能提升。针对一个一维电磁场FDTD算法问题,对其计算方法与过程做了简单描述。在Fortran语言环境中,采用OpenMP+细粒度并行的方式实现了并行化,即只对循环部分进行并行计算,并将该并行方法在一个三维瞬态场电偶极子辐射FDTD程序中进行了验证。该并行算法取得了较其他并行FDTD算法更快的加速比和更高的效率。结果表明基于OpenMP的电磁场FDTD并行算法具有非常好的加速比和效率。%The method of the electromagnetic field FDTD multi-core parallel programm design based on OpenMP is dis-cussed,in order to implement ideal performance improvement of this method in the application of more sophisticated algorithms. Aiming at a problem existing in one-dimensional electromagnetic FDTD algorithm , its calculation method and process are described briefly. In Fortran language environment,the parallelism is achieved with OpenMP technology and fine-grained parallel way,that is,the parallel computation is performed only for the cycle part. The parallel method was verified in a three-dimensional transient electromagnetic field FDTD program for dipole radiation. The parallel algorithm has achieved faster speedup and higher efficiency than other parallel FDTD algoritms. The results indicate that the electromagnetic field FDTD parallel algorithm based on OpenMP has a good speedup and efficiency.

  14. Mapping Field Trial IV Habitat Characterization (EX0907, EM302) on NOAA Ship Okeanos Explorer in Cordell Bank & Gulf of the Farallones National Marine Sanctuaries

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goals of this field trial cruise are more operational than exploratory. Like other field trials, this cruise has primary and secondary goals and objectives....

  15. Effects of Methimepip and JNJ-5207852 in Wistar rats exposed to an open-field with and without object and in Balb/c mice exposed to an open-space spatial maze

    Directory of Open Access Journals (Sweden)

    Abdel eEnnaceur

    2012-07-01

    Full Text Available The role of the histamine H3 receptor in anxiety is controversial, due to limitations in drug selectivity and limited validity of behavioral tests in previous studies. When exposed to an empty open field, Wistar rats spent more time in the outer area and made very low number of brief crossings in the central area. However, when an object occupied the central area, rats crossed frequently into and spent a long time in the central area. Administration of a range of different doses of methimepip (H3 receptor agonist reduced the entries into the central area with a novel object, indicating enhanced avoidance response. When balb/c mice were exposed to an open space 3D maze, neither methimepip nor JNJ-5207852 (H3 receptor antagonist/inverse agonist induced entry into the arms of the apparatus, indicative of lack of anxiolytic effects.

  16. Ecology and habitats of extremophiles.

    Science.gov (United States)

    Kristjánsson, J K; Hreggvidsson, G O

    1995-01-01

    This review describes the main natural extreme environments, characterized by high temperature, high and low pH and high salinity, that can be colonized by microorganisms. The environments covered are: freshwater alkaline hot springs; acidic solfatara fields; anaerobic geothermal mud and soils; acidic sulphur and pyrite areas; carbonate springs and alkaline soil; and soda and highly saline lakes. The community structure, in terms of available energy sources and representative autotrophic and heterotrophic microorganisms, is discussed for each type of habitat.

  17. Habitat Technology Research at DLR

    OpenAIRE

    Quantius, Dominik; Schubert, Daniel; Maiwald, Volker; Hauslage, Jens; Bornemann, Gerhild; Waßer, Kai; Hill, Jürgen; Henn, Norbert; Ruyters, Hans-Günter; Braun, Markus

    2013-01-01

    For long duration space missions a closed-loop system which can re-use of materials is mandatory. Also on Earth there are harsh environments or overpopulated areas where a sustainable handling of given goods is indispensable. Addressing these challenges the German Aerospace Center (DLR) conducts research in various fields of habitat technology development, which will be illustrated within this paper. There are various complementary topics, such as coordination and funding of building blocks f...

  18. Long-term field data and climate-habitat models show that orangutan persistence depends on effective forest management and greenhouse gas mitigation.

    Directory of Open Access Journals (Sweden)

    Stephen D Gregory

    Full Text Available BACKGROUND: Southeast Asian deforestation rates are among the world's highest and threaten to drive many forest-dependent species to extinction. Climate change is expected to interact with deforestation to amplify this risk. Here we examine whether regional incentives for sustainable forest management will be effective in improving threatened mammal conservation, in isolation and when combined with global climate change mitigation. METHODOLOGY/PRINCIPAL FINDINGS: Using a long time-series of orangutan nest counts for Sabah (2000-10, Malaysian Borneo, we evaluated the effect of sustainable forest management and climate change scenarios, and their interaction, on orangutan spatial abundance patterns. By linking dynamic land-cover and downscaled global climate model projections, we determine the relative influence of these factors on orangutan spatial abundance and use the resulting statistical models to identify habitat crucial for their long-term conservation. We show that land-cover change the degradation of primary forest had the greatest influence on orangutan population size. Anticipated climate change was predicted to cause reductions in abundance in currently occupied populations due to decreased habitat suitability, but also to promote population growth in western Sabah by increasing the suitability of presently unoccupied regions. CONCLUSIONS/SIGNIFICANCE: We find strong quantitative support for the Sabah government's proposal to implement sustainable forest management in all its forest reserves during the current decade; failure to do so could result in a 40 to 80 per cent regional decline in orangutan abundance by 2100. The Sabah orangutan is just one (albeit iconic example of a forest-dependent species that stands to benefit from sustainable forest management, which promotes conservation of existing forests.

  19. Long-Term Field Data and Climate-Habitat Models Show That Orangutan Persistence Depends on Effective Forest Management and Greenhouse Gas Mitigation

    Science.gov (United States)

    Gregory, Stephen D.; Brook, Barry W.; Goossens, Benoît; Ancrenaz, Marc; Alfred, Raymond; Ambu, Laurentius N.; Fordham, Damien A.

    2012-01-01

    Background Southeast Asian deforestation rates are among the world’s highest and threaten to drive many forest-dependent species to extinction. Climate change is expected to interact with deforestation to amplify this risk. Here we examine whether regional incentives for sustainable forest management will be effective in improving threatened mammal conservation, in isolation and when combined with global climate change mitigation. Methodology/Principal Findings Using a long time-series of orangutan nest counts for Sabah (2000–10), Malaysian Borneo, we evaluated the effect of sustainable forest management and climate change scenarios, and their interaction, on orangutan spatial abundance patterns. By linking dynamic land-cover and downscaled global climate model projections, we determine the relative influence of these factors on orangutan spatial abundance and use the resulting statistical models to identify habitat crucial for their long-term conservation. We show that land-cover change the degradation of primary forest had the greatest influence on orangutan population size. Anticipated climate change was predicted to cause reductions in abundance in currently occupied populations due to decreased habitat suitability, but also to promote population growth in western Sabah by increasing the suitability of presently unoccupied regions. Conclusions/Significance We find strong quantitative support for the Sabah government’s proposal to implement sustainable forest management in all its forest reserves during the current decade; failure to do so could result in a 40 to 80 per cent regional decline in orangutan abundance by 2100. The Sabah orangutan is just one (albeit iconic) example of a forest-dependent species that stands to benefit from sustainable forest management, which promotes conservation of existing forests. PMID:22970145

  20. Habitat Evaluation Procedures (HEP) Report; Forrest Conservation Area, Technical Report 2003-2004.

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Brent

    2005-01-01

    The Habitat Evaluation Procedure (HEP) study was performed to determine baseline habitat units on the 4,232-acre Forrest Conservation Area managed by the Confederated Tribes of Warm Springs Reservation of Oregon (Tribe) in Grant County, Oregon. The habitat evaluation is required as part of the Memorandum of Agreement between the Confederated Tribes of the Warm Springs and Bonneville Power Administration. Representatives from the Washington Department of Fish and Wildlife and the Tribes conducted the field surveys for the HEP. The survey collected data for habitat variables contained in habitat suitability index (HIS) models for wildlife species; the key species were black-capped chickadee (Poecile atricapilla), mallard (Anas platyrhynchos), mink (Mustela vison), western meadowlark (Sturnella neglecta), mule deer (Odocoileus hemionus), California Quail (Callipepla californica), and yellow warbler (Dendroica petechia). Cover types surveyed were grassland, meadow grassland, conifer forest, riparian tree shrub, shrub steppe, juniper forest, and juniper steppe. Other cover types mapped, but not used in the models were open water, roads, gravel pits, corrals, and residential.

  1. Exposure to an open-field arena increases c-Fos expression in a distributed anxiety-related system projecting to the basolateral amygdaloid complex

    DEFF Research Database (Denmark)

    Hale, M.W.; Hay-Schmidt, A.; Mikkelsen, J.D.

    2008-01-01

    to this region in combination with c-Fos immunostaining to identify cells responding to exposure to an open-field arena in low-light (8-13 lux) conditions (an anxiogenic stimulus in rats). Adult male Wistar rats received a unilateral microinjection of 4% CTb in phosphate-buffered saline into the basolateral...... amygdaloid complex. Rats were housed individually for 11 days after CTb injections and handled (HA) for 2 min each day. On the test day rats were either, 1) exposed to an open-field in low-light conditions (8-13 lux) for 15 min (OF); 2) briefly HA or 3) left undisturbed (control). We report that dual...

  2. Lunar Habitat Would Be Assembled In Space

    Science.gov (United States)

    King, Charles B.; Butterfield, Ansel J.; Hypes, Warren D.; Simonsen, Lisa C.; Hall, John B., Jr.; Scott, A. Don, Jr.; Nealy, John E.

    1992-01-01

    Conceptual lunar habitat built inside external tank from National Space Transportation System (NSTS). Tank modified in low Earth orbit using existing structures and openings for access without compromising structural integrity. Designed for unmanned transport to orbit around Moon, and autonomous soft landing. Houses crew of 12 for 70 days between resupply missions.

  3. Management of air-borne viruses by "optical barriers" in protected agriculture and open-field crops.

    Science.gov (United States)

    Antignus, Yehezkel

    2014-01-01

    The incurable nature of viral diseases and the public awareness to the harmful effects of chemical pest control to the environment and human health led to the rise of the integrated pest management (IPM) concept. Cultural control methods serve today as a central pivot in the implementation of IPM. This group of methods is based on the understanding of the complex interactions between disease agents and their vectors as well as the interactions between the vectors and their habitat. This chapter describes a set of cultural control methods that are based on solar light manipulation in a way that interferes with vision behavior of insects, resulting in a significant crop protection against insect pests and their vectored viruses.

  4. [The influence of acute hypoxia on motility of rats in the open field test under the conditions of an altered photoperiod].

    Science.gov (United States)

    Sopova, I Iu

    2014-01-01

    The influence of acute hypoxia on the motility of rats under the conditions of an altered photoperiod in the open field test was studied. Thus, keeping the animals in constant darkness after the modeling of acute hypoxia leads to the depression of locomotive and exploratory components of the behavior. At the same time the animals that were kept under the conditions of constant light show a change in the correlation between the components of motility after the action of hypoxia.

  5. Association of pattern reversal VEP parameters with the mean defect of Humphrey visual field in patients of primary open angle glaucoma.

    Science.gov (United States)

    Kothari, Ruchi; Singh, Ramji; Singh, Smita; Bokariya, Pradeep

    2013-01-01

    Glaucoma is a chronic, progressive bilateral optic neuropathy which disturbs the structural or functional integrity of the optic nerve that causes characteristic atrophic changes in it, which leads to specific visual field defects over time with loss of visual function. Primary open angle glaucoma (POAG) is the most common form of glaucoma in India and is fast emerging as a major cause of bilateral blindness. This rural hospital based study was conducted to evaluate whether glaucomatous visual field defects particularly the mean defect of Humphrey visual field could be related to VEP parameters of patients having POAG. Visual field by Humphrey perimeter and simultaneous recordings of pattern reversal visual evoked potential (PRVEP) were assessed in 100 patients with POAG. There was a significant (P VEP changes observed by us in POAG patients were consistent with the progressing mean defect quantitatively. Therefore, it can be concluded that the VEP parameters can be useful quantitative indices in the evaluation of glaucomatous visual function damage.

  6. Chemical Concentrations in Field Mice from Open-Detonation Firing Sites TA-36 Minie and TA-39 Point 6 at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Fresquez, Philip R. [Los Alamos National Laboratory

    2011-01-01

    Field mice (mostly Peromyscus spp.) were collected at two open-detonation (high explosive) firing sites - Minie at Technical Area (TA) 36 and Point 6 at TA-39 - at Los Alamos National Laboratory in August of 2010 and in February of 2011 for chemical analysis. Samples of whole body field mice from both sites were analyzed for target analyte list elements (mostly metals), dioxin/furans, polychlorinated biphenyl congeners, high explosives, and perchlorate. In addition, uranium isotopes were analyzed in a composite sample collected from TA-36 Minie. In general, all constituents, with the exception of lead at TA-39 Point 6, in whole body field mice samples collected from these two open-detonation firing sites were either not detected or they were detected below regional statistical reference levels (99% confidence level), biota dose screening levels, and/or soil ecological chemical screening levels. The amount of lead in field mice tissue collected from TA-39 Point 6 was higher than regional background, and some lead levels in the soil were higher than the ecological screening level for the field mouse; however, these levels are not expected to affect the viability of the populations over the site as a whole.

  7. Solar UVB response of bioactives in strawberry (Fragaria × ananassa Duch. L.): a comparison of protected and open-field cultivation.

    Science.gov (United States)

    Josuttis, Melanie; Dietrich, Helmut; Treutter, Dieter; Will, Frank; Linnemannstöns, Ludger; Krüger, Erika

    2010-12-22

    Strawberries (Fragaria × ananassa Duch. cvs. Everest, Elsanta) were grown in a tunnel covered with two films, which were distinguished in their ultraviolet transparency, as well as under open-field conditions. One applied film was not transparent for UVB radiation, and the second film transmitted 70% of UVB radiation. During the present study, the nutritional value and quality parameters of the fruits were evaluated. Strawberries were UV-unresponsive in view of the content of ascorbic acid and sum parameters like total anthocyanins and antioxidant capacity measured with TEAC (trolox equivalent antioxidant capacity), ORAC (oxygen radical absorbance capacity) and total phenols. These parameters were mainly affected by sampling date and cultivar. However, HPLC analysis showed that individual phenolics were affected in the absence of UV radiation. The content of the anthocyanin cyanidin 3-glucoside and the flavonols quercetin 3-glucuronide and kaempferol 3-glucoside was decreased in the fruits grown under UV blocking film compared to open-field grown strawberries. By means of the UV transparent film the content of the mentioned flavonoids could be enhanced up to similar amounts like in open-field grown strawberries. All other phenolics were not consistently affected by UV radiation. This result was independent of cultivar.

  8. Evidence-based severity assessment: Impact of repeated versus single open-field testing on welfare in C57BL/6J mice.

    Science.gov (United States)

    Bodden, Carina; Siestrup, Sophie; Palme, Rupert; Kaiser, Sylvia; Sachser, Norbert; Richter, S Helene

    2017-08-22

    According to current guidelines on animal experiments, a prospective assessment of the severity of each procedure is mandatory. However, so far, the classification of procedures into different severity categories mainly relies on theoretic considerations, since it is not entirely clear which of the various procedures compromise the welfare of animals, or, to what extent. Against this background, a systematic empirical investigation of the impact of each procedure, including behavioral testing seems essential. Therefore, the present study was designed to elucidate the effects of repeated versus single testing on mouse welfare, using one of the most commonly used paradigms for behavioral phenotyping in behavioral neuroscience, the open-field test. In an independent groups design, mice experienced either repeated, single, or no open-field testing - procedures that are assigned to different severity categories. Interestingly, testing experiences did not affect fecal corticosterone metabolites, body weights, elevated plus-maze or home cage behavior differentially. Thus, with respect to the assessed endocrinological, physical, and behavioral outcome measures, no signs of compromised welfare could be detected in mice that were tested in the open-field repeatedly, once, or, not at all. These findings challenge current classification guidelines and may, furthermore, stimulate systematic research on the severity of single procedures involving living animals. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Two Volatile Organic Compounds Trigger Plant Self-Defense against a Bacterial Pathogen and a Sucking Insect in Cucumber under Open Field Conditions

    Directory of Open Access Journals (Sweden)

    Choong-Min Ryu

    2013-05-01

    Full Text Available Systemic acquired resistance (SAR is a plant self-defense mechanism against a broad-range of pathogens and insect pests. Among chemical SAR triggers, plant and bacterial volatiles are promising candidates for use in pest management, as these volatiles are highly effective, inexpensive, and can be employed at relatively low concentrations compared with agrochemicals. However, such volatiles have some drawbacks, including the high evaporation rate of these compounds after application in the open field, their negative effects on plant growth, and their inconsistent levels of effectiveness. Here, we demonstrate the effectiveness of volatile organic compound (VOC-mediated induced resistance against both the bacterial angular leaf spot pathogen, Pseudononas syringae pv. lachrymans, and the sucking insect aphid, Myzus persicae, in the open field. Using the VOCs 3-pentanol and 2-butanone where fruit yields increased gave unexpectedly, a significant increase in the number of ladybird beetles, Coccinella septempunctata, a natural enemy of aphids. The defense-related gene CsLOX was induced by VOC treatment, indicating that triggering the oxylipin pathway in response to the emission of green leaf volatiles can recruit the natural enemy of aphids. These results demonstrate that VOCs may help prevent plant disease and insect damage by eliciting induced resistance, even in open fields.

  10. Laser-induced thermotherapy (LITT) - evaluation of a miniaturised applicator and implementation in a 1.0-T high-field open MRI applying a porcine liver model

    Energy Technology Data Exchange (ETDEWEB)

    Streitparth, Florian; Knobloch, Gesine; Rump, J.; Wonneberger, Uta; Hamm, Bernd; Teichgraeber, Ulf [Charite, Humboldt-Universitaet zu Berlin, Department of Radiology, Berlin (Germany); Balmert, Dirk [Somatex Medical Technologies GmbH, Teltow (Germany); Chopra, Sascha [Charite, Humboldt-University, Department of General, Visceral, and Transplantation Surgery, Berlin (Germany); Philipp, Carsten [Elisabeth Klinik, Department of Laser Medicine, Berlin (Germany)

    2010-11-15

    To evaluate the feasibility and safety of a novel LITT applicator for thermal ablation of liver malignancies in 1.0-T high-field open MRI. A miniaturised 6-F double-tubed protective catheter with a closed cooling circuit was used with a flexible laser fibre, connected to a 1,064-nm Nd:YAG laser and evaluated in non-perfused porcine livers (18-30 W for 10-20 min, 2-W and 2-min increments; n = 210/applicator) in reference to an established 9-F system. As a proof of concept, MR-guided LITT was performed in two healthy domestic pigs in high-field open MRI. Ex-vivo, the coagulation volumes induced by the 6-F system with maximum applicable power of 24 W for 20 min (33.0 {+-} 4.4 cm{sup 3}) did not differ significantly from those set with the 9-F system at 30 W for 20 min (35.8 {+-} 4.9 cm{sup 3}) (p = 0.73). A flow-rate of 15 ml/min of the cooling saline solution was sufficient. MR navigation and thermometry were feasible. The miniaturised 6-F applicator can create comparable coagulation sizes to those of the 9-F system. Applicator guidance and online-thermometry in high-field open MRI are feasible. (orig.)

  11. Two volatile organic compounds trigger plant self-defense against a bacterial pathogen and a sucking insect in cucumber under open field conditions.

    Science.gov (United States)

    Song, Geun Cheol; Ryu, Choong-Min

    2013-05-08

    Systemic acquired resistance (SAR) is a plant self-defense mechanism against a broad-range of pathogens and insect pests. Among chemical SAR triggers, plant and bacterial volatiles are promising candidates for use in pest management, as these volatiles are highly effective, inexpensive, and can be employed at relatively low concentrations compared with agrochemicals. However, such volatiles have some drawbacks, including the high evaporation rate of these compounds after application in the open field, their negative effects on plant growth, and their inconsistent levels of effectiveness. Here, we demonstrate the effectiveness of volatile organic compound (VOC)-mediated induced resistance against both the bacterial angular leaf spot pathogen, Pseudononas syringae pv. lachrymans, and the sucking insect aphid, Myzus persicae, in the open field. Using the VOCs 3-pentanol and 2-butanone where fruit yields increased gave unexpectedly, a significant increase in the number of ladybird beetles, Coccinella septempunctata, a natural enemy of aphids. The defense-related gene CsLOX was induced by VOC treatment, indicating that triggering the oxylipin pathway in response to the emission of green leaf volatiles can recruit the natural enemy of aphids. These results demonstrate that VOCs may help prevent plant disease and insect damage by eliciting induced resistance, even in open fields.

  12. GPR30 activation decreases anxiety in the open field test but not in the elevated plus maze test in female mice.

    Science.gov (United States)

    Anchan, Divya; Clark, Sara; Pollard, Kevin; Vasudevan, Nandini

    2014-01-01

    The GPR30 is a novel estrogen receptor (ER) that is a candidate membrane ER based on its binding to 17β estradiol and its rapid signaling properties such as activation of the extracellular-regulated kinase (ERK) pathway. Its distribution in the mouse limbic system predicts a role for this receptor in the estrogenic modulation of anxiety behaviors in the mouse. A previous study showed that chronic administration of a selective agonist to the GPR30 receptor, G-1, in the female rat can improve spatial memory, suggesting that GPR30 plays a role in hippocampal-dependent cognition. In this study, we investigated the effect of a similar chronic administration of G-1 on behaviors that denote anxiety in adult ovariectomized female mice, using the elevated plus maze (EPM) and the open field test as well as the activation of the ERK pathway in the hippocampus. Although estradiol benzoate had no effect on behaviors in the EPM or the open field, G-1 had an anxiolytic effect solely in the open field that was independent of ERK signaling in either the ventral or dorsal hippocampus. Such an anxiolytic effect may underlie the ability of G-1 to increase spatial memory, by acting on the hippocampus.

  13. Propentofylline treatment on open field behavior in rats with focal ethidium bromide-induced demyelination in the ventral surface of the brainstem.

    Science.gov (United States)

    Martins-Júnior, J L; Bernardi, M M; Bondan, E F

    2016-03-01

    Propentofylline (PPF) is a xanthine derivative with pharmacological effects that are distinct from those of classic methylxanthines. It depresses the activation of microglial cells and astrocytes, which is associated with neuronal damage during neural inflammation and hypoxia. Our previous studies showed that PPF improved remyelination following gliotoxic lesions that were induced by ethidium bromide (EB). In the present study, the long-term effects of PPF on open field behavior in rats with EB-induced focal demyelination were examined. The effects of PPF were first evaluated in naive rats that were not subjected to EB lesions. Behavior in the beam walking test was also evaluated during chronic PPF treatment because impairments in motor coordination can interfere with behavior in the open field. The results showed that PPF treatment in unlesioned rats decreased general activity and caused motor impairment in the beam walking test. Gliotoxic EB injections increased general activity in rats that were treated with PPF compared with rats that received saline solution. Motor incoordination was also attenuated in PPF-treated rats. These results indicate that PPF reversed the effects of EB lesions on behavior in the open field and beam walking test.

  14. Effects of ambient temperature and early open-field response on the behaviour, feed intake and growth of fast- and slow-growing broiler strains

    DEFF Research Database (Denmark)

    Nielsen, Birte Lindstrøm

    2012-01-01

    in an open-field test on day 3 after hatching, fast-growing Ross 208 and slow-growing i657 chickens were allocated on day 13 to one of the 48 groups. Each group included either six active or six passive birds from each strain and the groups were housed in floor-pens littered with wood chips and fitted......Increased activity improves broiler leg health, but also increases the heat production of the bird. This experiment investigated the effects of early open-field activity and ambient temperature on the growth and feed intake of two strains of broiler chickens. On the basis of the level of activity...... with two heat lamps. Each group was fed ad libitum and subjected to one of the three temperature treatments: two (HH; 268C), one (HC; 168C to 268C) or no (CC; 168C) heat lamps turned on. Production and behavioural data were collected every 2 weeks until day 57. For both strains, early open-field activity...

  15. Trends on Habitat Management

    Directory of Open Access Journals (Sweden)

    Raluca Giuşcă

    2008-01-01

    Full Text Available According to traditional image, human habitat constitution is the result of natural inter-relations, the fundamental premise of the existence of natural resources, the climate, and the access to more developed proximities for commercial trading. Human habitat represents a complex system, with environmental values, having live and natural components that are inter-related. The dwelling is the fundamental component of the habitat and by relationship with the other components determines the level of habitation.

  16. Calcareous Bio-Concretions in the Northern Adriatic Sea: Habitat Types, Environmental Factors that Influence Habitat Distributions, and Predictive Modeling.

    Science.gov (United States)

    Falace, Annalisa; Kaleb, Sara; Curiel, Daniele; Miotti, Chiara; Galli, Giovanni; Querin, Stefano; Ballesteros, Enric; Solidoro, Cosimo; Bandelj, Vinko

    2015-01-01

    Habitat classifications provide guidelines for mapping and comparing marine resources across geographic regions. Calcareous bio-concretions and their associated biota have not been exhaustively categorized. Furthermore, for management and conservation purposes, species and habitat mapping is critical. Recently, several developments have occurred in the field of predictive habitat modeling, and multiple methods are available. In this study, we defined the habitats constituting northern Adriatic biogenic reefs and created a predictive habitat distribution model. We used an updated dataset of the epibenthic assemblages to define the habitats, which we verified using the fuzzy k-means (FKM) clustering method. Redundancy analysis was employed to model the relationships between the environmental descriptors and the FKM membership grades. Predictive modelling was carried out to map habitats across the basin. Habitat A (opportunistic macroalgae, encrusting Porifera, bioeroders) characterizes reefs closest to the coastline, which are affected by coastal currents and river inputs. Habitat B is distinguished by massive Porifera, erect Tunicata, and non-calcareous encrusting algae (Peyssonnelia spp.). Habitat C (non-articulated coralline, Polycitor adriaticus) is predicted in deeper areas. The onshore-offshore gradient explains the variability of the assemblages because of the influence of coastal freshwater, which is the main driver of nutrient dynamics. This model supports the interpretation of Habitat A and C as the extremes of a gradient that characterizes the epibenthic assemblages, while Habitat B demonstrates intermediate characteristics. Areas of transition are a natural feature of the marine environment and may include a mixture of habitats and species. The habitats proposed are easy to identify in the field, are related to different environmental features, and may be suitable for application in studies focused on other geographic areas. The habitat model outputs

  17. Calcareous Bio-Concretions in the Northern Adriatic Sea: Habitat Types, Environmental Factors that Influence Habitat Distributions, and Predictive Modeling.

    Directory of Open Access Journals (Sweden)

    Annalisa Falace

    Full Text Available Habitat classifications provide guidelines for mapping and comparing marine resources across geographic regions. Calcareous bio-concretions and their associated biota have not been exhaustively categorized. Furthermore, for management and conservation purposes, species and habitat mapping is critical. Recently, several developments have occurred in the field of predictive habitat modeling, and multiple methods are available. In this study, we defined the habitats constituting northern Adriatic biogenic reefs and created a predictive habitat distribution model. We used an updated dataset of the epibenthic assemblages to define the habitats, which we verified using the fuzzy k-means (FKM clustering method. Redundancy analysis was employed to model the relationships between the environmental descriptors and the FKM membership grades. Predictive modelling was carried out to map habitats across the basin. Habitat A (opportunistic macroalgae, encrusting Porifera, bioeroders characterizes reefs closest to the coastline, which are affected by coastal currents and river inputs. Habitat B is distinguished by massive Porifera, erect Tunicata, and non-calcareous encrusting algae (Peyssonnelia spp.. Habitat C (non-articulated coralline, Polycitor adriaticus is predicted in deeper areas. The onshore-offshore gradient explains the variability of the assemblages because of the influence of coastal freshwater, which is the main driver of nutrient dynamics. This model supports the interpretation of Habitat A and C as the extremes of a gradient that characterizes the epibenthic assemblages, while Habitat B demonstrates intermediate characteristics. Areas of transition are a natural feature of the marine environment and may include a mixture of habitats and species. The habitats proposed are easy to identify in the field, are related to different environmental features, and may be suitable for application in studies focused on other geographic areas. The habitat

  18. Type 'A' and 'B' recovery revisited: The role of field-edge habitats for Collembola and macroarthropod community recovery after insecticide treatment

    NARCIS (Netherlands)

    Frampton, G.K.; Gould, P.J.L.; Brink, van den P.J.; Hendy, E.

    2007-01-01

    Previous work has identified two patterns of arthropod recovery after insecticide applications to arable crops: dispersal-mediated recolonisation from untreated areas (Type A) and recolonisation within treated areas assisted by reduced predation (Type B). In this study, connectivity between field-ed

  19. Free/Libre Open Source Software Implementation in Schools: Evidence from the Field and Implications for the Future

    Science.gov (United States)

    Lin, Yu-Wei; Zini, Enrico

    2008-01-01

    This empirical paper shows how free/libre open source software (FLOSS) contributes to mutual and collaborative learning in an educational environment. Unlike proprietary software, FLOSS allows extensive customisation of software to support the needs of local users better. This also allows users to participate more proactively in the development…

  20. Shorebird Habitat Suitability Indicies

    Data.gov (United States)

    Arctic Landscape Conservation Cooperative — This dataset consists of predicted habitat suitability indices and species richness for eight shorebird species (Black-bellied Plover [Pluvialis squatarola],...

  1. Habitat use of little owls (Athene noctua) in a decreasing farmland population in Denmark

    DEFF Research Database (Denmark)

    Sunde, P.; Thorup, K.; Jacobsen, L. B.

    habitat types (analysed with GLMMs, treating territory ID as random factor) of different habitat types (categorised as ¡§cultivated fields¡¨, ¡§gardens and built-up areas¡¨, ¡§grazed land¡¨, ¡§continuous tree vegetation¡¨ and ¡§uncultivated open areas¡¨) was similar for males and females, but varied...... the rest of the year. At temperatures between 0"aC and 10"aC, more than 75% of all fixes of silent (potentially foraging) owls were located in open habitats, whereas areas with trees and buildings were increasingly used at temperatures below 0"aC or above 10"aC, apparently reflecting temperature dependent...... hunting tactics. However, relative to availability, hedgerows were generally not preferred over open land. The results show that little owls on an annual basis utilized most available habitats within their range including intensively farmed cropland, but that foraging decisions were conditioned...

  2. MPI + OpenCL implementation of a phase-field method incorporating CALPHAD description of Gibbs energies on heterogeneous computing platforms

    Science.gov (United States)

    Gerald Tennyson, P.; G. M., Karthik; Phanikumar, G.

    2015-01-01

    Phase-field method uses a non-conserved order parameter to define the phase state of a system and is a versatile method for moving boundary problems. It is a method of choice for simulating microstructure evolution in the domain of materials engineering. Solution of phase-field evolution equations avoids explicit tracking of interfaces and is often implemented on a structured grid to capture microstructure evolution in a simple and elegant manner. Restrictions on the grid size to accurately capture the interface curvature effects lead to large number of grid points in the computational domain and render the simulation computationally intensive for realistic simulations in 3D. However, the availability of powerful heterogeneous computing platforms and super clusters provides the advantage to perform large scale phase-field simulations efficiently. This paper discusses a portable implementation to extend simulations across multiple CPUs using MPI to include use of GPUs using OpenCL. The solution scheme adapts an isotropic stencil that avoids grid-induced anisotropy. Use of separate OpenCL kernels for problem specific portions of the code ensure that the approach can be extended to different problems. Performance analysis of parallel strategies used in the study illustrate the massively parallel computing possibility for phase-field simulations across heterogeneous platforms.

  3. Effects of Photosynthetically Active Radiation and Air Temperature on CO2 Uptake of Pterocarpus macrocarpus in the Open Field

    Institute of Scientific and Technical Information of China (English)

    Sureeporn Kerdkankaew; Jesada Luangjame; Pojanie Khummongkol

    2005-01-01

    Since trees and plants can absorb CO2, forests are widely regarded as a carbon sink that may control the amount of CO2 in the atmosphere. The CO2 uptake rate of plants is affected by the plant species and environmental conditions such as photosynthetically active radiation (PAR), temperature, water and nutrient contents. PAR is the most immediate environmental control on photosynthesis while air temperature affects both photorespiration and dark respiration. In the natural condition, PAR and temperature play an important role in net CO2 uptake. The effects of PAR and air temperature on the CO2 uptake of Pterocarpus macrocarpus grown in a natural habitat were studied in the present work. Due to many uncontrollable factors, a simple rectangular hyperbola could not represent the measured data. The data were divided into groups of 2℃ intervals; CO2 uptake in each group may then be related to PAR by a rectangular hyperbola function. Using the obtained functions, the effect of PAR was removed from the original data. The PAR-independent CO2 uptake was then related to air temperature. Finally, the effects of PAR (I) and air temperature (Ta) on the CO2 uptake rate (A) were combined as:A= [(-0.0575 Ta2+ 2.6691 Ta-23.264)I/(-4.8794Ta2+227.13Ta-2456.9)+I](-0.00766Ta2+0.40666Ta-3.99924)

  4. The study of seasonal composition and dynamics of wetland ecosystems and wintering bird habitat at Poyang Lake, PR China using object-based image analysis and field observations

    Science.gov (United States)

    Dronova, Iryna

    Wetlands are among the most productive ecosystems in the world which support critical ecological services and high biological diversity yet are vulnerable to climate change and human activities. In this thesis, I investigated the capabilities of satellite remote sensing with medium spatial resolution and object-based image analysis (OBIA) methods to elucidate seasonal composition and dynamics of wetland ecosystems and indicators of habitat for wintering waterbirds in a large conservation hotspot of Poyang Lake, PR China. I first examined changes in major wetland cover types during the low water period when Poyang Lake provides habitat to large numbers of migratory birds from the East Asian pathway. I used OBIA to map and analyze the transitions among water, vegetation, mudflat and sand classes from four 32-m Beijing-1 microsatellite images between late fall 2007 and early spring 2008. This analysis revealed that, while transitions among wetland classes were strongly associated with precipitation and flood-driven hydrological variation, the overall dynamics were a more complex interplay of vegetation phenology, disturbance and post-flood exposure. Remote sensing signals of environmental processes were more effectively captured by changes in fuzzy memberships to each class per location than by changes in spatial extents of the best-matching classes alone. The highest uncertainty in the image analysis corresponded to transitional wetland states at the end of the major flood recession in November and to heterogeneous mudflat areas at the land-water interface during the whole study period. Results suggest seasonally exposed mudflat features as important targets for future research due to heterogeneity and uncertainty of their composition, variable spatial distribution and sensitivity to hydrological dynamics. I further explored the potential of OBIA to overcome the limitations of the traditional pixel-based image classification methods in characterizing Poyang Lake

  5. Living in a caatinga-rocky field transitional habitat: ecological aspects of the whiptail lizard Cnemidophorus ocellifer (Teiidae in northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Vanderlaine A Menezes

    2011-02-01

    Full Text Available The ecology of the active forager lizard Cnemidophorus ocellifer (Spix, 1825 was studied to analyze food habits, thermal ecology and habitat use, in the Morro do Chapéu municipality (11º29'S, 41º07'W, state of Bahia, Brazil. Lizards (N = 34 were collected with rubber bands or with an air rifle and, for each individual, we recorded cloacal temperature (Tc, air temperature (Ta (1 cm above the substrate and substrate temperature (Ts (to nearest 0.2ºC. We registered the microhabitat used by each animal at the moment of first sight and measured its morphological variables (nearest 0.1 mm. In the laboratory, we registered the number of items of each prey category to the taxonomic level of Order, its dimensions and frequencies. Data showed that, numerically, the category most consumed was Isoptera (84.4%. Volumetrically, the diet was composed predominantly by Orthoptera (27.5% and Isoptera (21.5%. Prey items that occur aggregated in the environment (termites were important in the diet of C. ocellifer, a characteristic of active foragers. Males and females did not differ in the types of prey consumed. Cnemidophorus ocellifer had a mean Tc in activity of 37.6 ± 1.6ºC and the relationship between Tc and ambient temperatures (Ts and Ta was positive and significant (F2,28 = 4.814; R² = 0.256; p < 0.05. Most lizards were first sighted on leaf litter inside shrubs (45.5% and on leaf litter at shrub edge (42.4%. Cnemidophorus ocellifer had a relatively high mean Tc during activity, with Ts explaining most of the variation in lizard Tc.

  6. Determinants of habitat selection by hatchling Australian freshwater crocodiles.

    Science.gov (United States)

    Somaweera, Ruchira; Webb, Jonathan K; Shine, Richard

    2011-01-01

    Animals almost always use habitats non-randomly, but the costs and benefits of using specific habitat types remain unknown for many types of organisms. In a large lake in northwestern Australia (Lake Argyle), most hatchling (crocodiles (Crocodylus johnstoni) are found in floating vegetation mats or grassy banks rather than the more widely available open banks. Mean body sizes of young crocodiles did not differ among the three habitat types. We tested four potential explanations for non-random habitat selection: proximity to nesting sites, thermal conditions, food availability, and exposure to predation. The three alternative habitat types did not differ in proximity to nesting sites, or in thermal conditions. Habitats with higher food availability harboured more hatchlings, and feeding rates (obtained by stomach-flushing of recently-captured crocodiles) were highest in such areas. Predation risk may also differ among habitats: we were twice as likely to capture a crocodile after seeing it in open-bank sites than in the other two habitat types. Thus, habitat selection of hatchling crocodiles in this system may be driven both by prey availability and by predation risk.

  7. Determinants of habitat selection by hatchling Australian freshwater crocodiles.

    Directory of Open Access Journals (Sweden)

    Ruchira Somaweera

    Full Text Available Animals almost always use habitats non-randomly, but the costs and benefits of using specific habitat types remain unknown for many types of organisms. In a large lake in northwestern Australia (Lake Argyle, most hatchling (<12-month-old freshwater crocodiles (Crocodylus johnstoni are found in floating vegetation mats or grassy banks rather than the more widely available open banks. Mean body sizes of young crocodiles did not differ among the three habitat types. We tested four potential explanations for non-random habitat selection: proximity to nesting sites, thermal conditions, food availability, and exposure to predation. The three alternative habitat types did not differ in proximity to nesting sites, or in thermal conditions. Habitats with higher food availability harboured more hatchlings, and feeding rates (obtained by stomach-flushing of recently-captured crocodiles were highest in such areas. Predation risk may also differ among habitats: we were twice as likely to capture a crocodile after seeing it in open-bank sites than in the other two habitat types. Thus, habitat selection of hatchling crocodiles in this system may be driven both by prey availability and by predation risk.

  8. Targeting a Hidden Enemy: Pyriproxyfen Autodissemination Strategy for the Control of the Container Mosquito Aedes albopictus in Cryptic Habitats.

    Directory of Open Access Journals (Sweden)

    Kshitij Chandel

    2016-12-01

    Full Text Available The Asian tiger mosquito, Aedes albopictus, is a vector of dengue, Chikungunya, and Zika viruses. This mosquito inhabits a wide range of artificial water-holding containers in urban and suburban areas making it difficult to control. We tested the hypothesis that female-driven autodissemination of an insect growth regulator could penetrate cryptic oviposition habitats difficult to treat with conventional insecticidal sprays.Oviposition preferences of Ae. albopictus females for open and cryptic cups were tested in semi-field experiments. Two conventional larvicidal sprayers were tested to determine droplet penetration and larvicidal efficacy in open and cryptic habitats using Bacillus thuringiensis var. israelensis (Bti in the field. Finally, the efficacy of pyriproxyfen autodissemination stations was assessed in cryptic and open cups in residential areas during 2013 and 2014.Gravid females strongly preferred cryptic (53.1±12.9 eggs/cup over open (10.3±4.3 eggs/cup cups for oviposition. Cryptic cups showed limited droplet penetration and produced 0.1-0.3% larval mortality with a conventional backpack and low-volume sprays of Bti. The autodissemination stations effectively contaminated these cryptic cups (59.3-84.6% and produced 29.7-40.8% pupal mortality during 2013-2014. Significant pupal mortality was also observed in open cups.The autodissemination station effectively exploits the oviposition behavior of wild gravid females to deliver pyriproxyfen to targeted oviposition habitats. Although the pupal mortality in cryptic cups was relatively lower than expected for the effective vector control. Autodissemination approach may be a suitable supporting tool to manage Ae. albopictus immatures in the cryptic habitats those are less accessible to conventional larvicidal sprays.

  9. Targeting a Hidden Enemy: Pyriproxyfen Autodissemination Strategy for the Control of the Container Mosquito Aedes albopictus in Cryptic Habitats

    Science.gov (United States)

    Suman, Devi Shankar; Wang, Yi; Unlu, Isik; Williges, Eric; Williams, Gregory M.; Gaugler, Randy

    2016-01-01

    Background The Asian tiger mosquito, Aedes albopictus, is a vector of dengue, Chikungunya, and Zika viruses. This mosquito inhabits a wide range of artificial water-holding containers in urban and suburban areas making it difficult to control. We tested the hypothesis that female-driven autodissemination of an insect growth regulator could penetrate cryptic oviposition habitats difficult to treat with conventional insecticidal sprays. Methodology Oviposition preferences of Ae. albopictus females for open and cryptic cups were tested in semi-field experiments. Two conventional larvicidal sprayers were tested to determine droplet penetration and larvicidal efficacy in open and cryptic habitats using Bacillus thuringiensis var. israelensis (Bti) in the field. Finally, the efficacy of pyriproxyfen autodissemination stations was assessed in cryptic and open cups in residential areas during 2013 and 2014. Principal Findings Gravid females strongly preferred cryptic (53.1±12.9 eggs/cup) over open (10.3±4.3 eggs/cup) cups for oviposition. Cryptic cups showed limited droplet penetration and produced 0.1–0.3% larval mortality with a conventional backpack and low-volume sprays of Bti. The autodissemination stations effectively contaminated these cryptic cups (59.3–84.6%) and produced 29.7–40.8% pupal mortality during 2013–2014. Significant pupal mortality was also observed in open cups. Conclusions The autodissemination station effectively exploits the oviposition behavior of wild gravid females to deliver pyriproxyfen to targeted oviposition habitats. Although the pupal mortality in cryptic cups was relatively lower than expected for the effective vector control. Autodissemination approach may be a suitable supporting tool to manage Ae. albopictus immatures in the cryptic habitats those are less accessible to conventional larvicidal sprays. PMID:28033379

  10. Near-Field Acoustic Power Level Analysis of F31/A31 Open Rotor Model at Simulated Cruise Conditions, Technical Report II

    Science.gov (United States)

    Sree, Dave

    2015-01-01

    Near-field acoustic power level analysis of F31A31 open rotor model has been performed to determine its noise characteristics at simulated cruise flight conditions. The non-proprietary parts of the test data obtained from experiments in the 8x6 supersonic wind tunnel were provided by NASA-Glenn Research Center. The tone and broadband components of total noise have been separated from raw test data by using a new data analysis tool. Results in terms of sound pressure levels, acoustic power levels, and their variations with rotor speed, freestream Mach number, and input shaft power, with different blade-pitch setting angles at simulated cruise flight conditions, are presented and discussed. Empirical equations relating models acoustic power level and input shaft power have been developed. The near-field acoustic efficiency of the model at simulated cruise conditions is also determined. It is hoped that the results presented in this work will serve as a database for comparison and improvement of other open rotor blade designs and also for validating open rotor noise prediction codes.

  11. Relation between the Reducibility Structures and between the Master Actions in the Witten Formulation and the Berkovits Formulation of Open Superstring Field Theory

    CERN Document Server

    Iimori, Yuki

    2015-01-01

    Developing the analysis in JHEP 03 (2014) 044 [arXiv:1312.1677] by the present authors et al., we clarify the relation between the Witten formulation and the Berkovits formulation of open superstring field theory at the level of the master action, namely the solution to the classical master equation in the Batalin-Vilkovisky formalism, which is the key for the path-integral quantization. We first scrutinize the reducibility structure, a detailed gauge structure containing the information about ghost string fields. Then, extending the condition for partial gauge fixing introduced in the above-mentioned paper to the sector of ghost string fields, we investigate the master action. We show that the reducibility structure and the master action under partial gauge fixing of the Berkovits formulation can be regarded as the regularized versions of those in the Witten formulation.

  12. High-resolution small field-of-view magnetic resonance image acquisition system using a small planar coil and a pneumatic manipulator in an open MRI scanner.

    Science.gov (United States)

    Miki, Kohei; Masamune, Ken

    2015-10-01

    Low-field open magnetic resonance imaging (MRI) is frequently used for performing image-guided neurosurgical procedures. Intraoperative magnetic resonance (MR) images are useful for tracking brain shifts and verifying residual tumors. However, it is difficult to precisely determine the boundary of the brain tumors and normal brain tissues because the MR image resolution is low, especially when using a low-field open MRI scanner. To overcome this problem, a high-resolution MR image acquisition system was developed and tested. An MR-compatible manipulator with pneumatic actuators containing an MR signal receiver with a small radiofrequency (RF) coil was developed. The manipulator had five degrees of freedom for position and orientation control of the RF coil. An 8-mm planar RF coil with resistance and inductance of 2.04 [Formula: see text] and 1.00 [Formula: see text] was attached to the MR signal receiver at the distal end of the probe. MR images of phantom test devices were acquired using the MR signal receiver and normal head coil for signal-to-noise ratio (SNR) testing. The SNR of MR images acquired using the MR signal receiver was 8.0 times greater than that of MR images acquired using the normal head coil. The RF coil was moved by the manipulator, and local MR images of a phantom with a 2-mm grid were acquired using the MR signal receiver. A wide field-of-view MR image was generated from a montage of local MR images. A small field-of-view RF system with a pneumatic manipulator was integrated in a low-field MRI scanner to allow acquisition of both wide field-of-view and high-resolution MR images. This system is promising for image-guided neurosurgery as it may allow brain tumors to be observed more clearly and removed precisely.

  13. Construção do "Habitat-Ação" saudável por meio de fundamentação teórico-metodológica do campo da semiologia do ambiente construído The construction of the healthy "Habitat-Action" through a theoretical-methodological framework from the field of the semiotics of the built environment

    Directory of Open Access Journals (Sweden)

    Simone Cynamon Cohen

    2012-09-01

    Full Text Available O artigo apresenta o processo de como se dá a qualidade do ambiente construído e as inter-relações com o seu entorno. Inicia-se com a reflexão sobre o campo da promoção da saúde, habitação saudável e conceitos correlatos. Em seguida, são introduzidas questões fundamentais para o desenvolvimento de propostas sociais de habitats saudáveis. Um caminho possível de aprofundamento teórico-metodológico desse campo dá-se por meio da Semiologia do Ambiente Construído, como ferramenta para a análise dos aspectos da habitabilidade. Aspectos fundamentais para construção de espacialidades saudáveis. Construção que se torna possível por meio da elaboração de políticas públicas saudáveis e da utilização de uma linguagem analítica para o ambiente construído. Ambas importantes no processo de desenvolvimento local, integrado e sustentável, adicionadas e incorporadas ao conceito e à prática metodológica da habitação saudável, campo intersetorial da promoção da saúde, habitação e meio ambiente.This article approaches how the quality of the built environment and the interrelationships to its surroundings occur. It begins with a reflection on the field of health promotion, healthy housing and related concepts. Then it introduces the key issues concerning the development of social proposals for healthy habitats. One possible way of furthering the theoretical and methodological framework in this field is by using the Semiotics of the Built Environment as a tool to examine aspects of habitability. Fundamental aspects for building healthy spatialities. A construction that is made possible through the development of healthy public policies and through the use of an analytic language for the built environment. Both are important in the local, integrated and sustainable process of development, added and incorporated into the concept and methodological practice of healthy housing, which is an intersectoral field of health

  14. Enrichment of radon and carbon dioxide in the open atmosphere of an Australian coal seam gas field.

    Science.gov (United States)

    Tait, Douglas R; Santos, Isaac R; Maher, Damien T; Cyronak, Tyler J; Davis, Rachael J

    2013-04-02

    Atmospheric radon ((222)Rn) and carbon dioxide (CO2) concentrations were used to gain insight into fugitive emissions in an Australian coal seam gas (CSG) field (Surat Basin, Tara region, Queensland). (222)Rn and CO2 concentrations were observed for 24 h within and outside the gas field. Both (222)Rn and CO2 concentrations followed a diurnal cycle with night time concentrations higher than day time concentrations. Average CO2 concentrations over the 24-h period ranged from ~390 ppm at the control site to ~467 ppm near the center of the gas field. A ~3 fold increase in maximum (222)Rn concentration was observed inside the gas field compared to outside of it. There was a significant relationship between maximum and average (222)Rn concentrations and the number of gas wells within a 3 km radius of the sampling sites (n = 5 stations; p radon relationship was a response to enhanced emissions within the gas field related to both point (well heads, pipelines, etc.) and diffuse soil sources. Radon may be useful in monitoring enhanced soil gas fluxes to the atmosphere due to changes in the geological structure associated with wells and hydraulic fracturing in CSG fields.

  15. Breeding habitats of mosquitoes in Goa.

    Science.gov (United States)

    Kulkarni, S M; Naik, P S

    1989-03-01

    Studies carried out in Goa from 1986 to 1987 revealed immature stages of 43 species of mosquitoes. Breeding habitats were divided into three categories, viz., (i) Ground water habitats consisting of ground pools and tanks, rocky pools, paddy fields and stream beds, yielding 30 species; (ii) Plant habitats consisting of tree holes and fallen coconut shells and leaf sheaths yielding 20 species; and (iii) Domestic/peridomestic habitats consisting of cement tanks, glass, earthen, metallic containers and tyres yielding 11 species. Five species viz., Anopheles subpictus, Aedes albopictus, Armigeres subalbatus, Culex quinquefasciatus and Cx. pallidothorax were found in all three types of habitats. Cx. tritaeniorhynchus preferred to breed in ground pools and paddy fields but was found in domestic cement tanks and ground tanks in adverse season. Majority of the anophelines and culicines were found in ground water habitats. Five out of 11 species of Aedes were found in tree holes. Aedes aegypti and Toxorhynchites splendens were found only in discarded tyres. Three species of the genus Uranotaenia, viz., U. bicolor, U. stricklandi and U. campestris were recorded from stream beds and plant containers.

  16. Habitat Blocks and Wildlife Corridors

    Data.gov (United States)

    Vermont Center for Geographic Information — Habitat blocks are areas of contiguous forest and other natural habitats that are unfragmented by roads, development, or agriculture. Vermonts habitat blocks are...

  17. Synthesis and Enhanced Field-Emission of Thin-Walled, Open-Ended, and Well-Aligned N-Doped Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Hu Qiang

    2010-01-01

    Full Text Available Abstract Thin-walled, open-ended, and well-aligned N-doped carbon nanotubes (CNTs on the quartz slides were synthesized by using acetonitrile as carbon sources. As-obtained products possess large thin-walled index (TWI, defined as the ratio of inner diameter and wall thickness of a CNT. The effect of temperature on the growth of CNTs using acetonitrile as the carbon source was also investigated. It is found that the diameter, the TWI of CNTs increase and the Fe encapsulation in CNTs decreases as the growth temperature rises in the range of 780–860°C. When the growth temperature is kept at 860°C, CNTs with TWI = 6.2 can be obtained. It was found that the filed-emission properties became better as CNT growth temperatures increased from 780 to 860°C. The lowest turn-on and threshold field was 0.27 and 0.49 V/μm, respectively. And the best field-enhancement factors reached 1.09 × 105, which is significantly improved about an order of magnitude compared with previous reports. In this study, about 30 × 50 mm2 free-standing film of thin-walled open-ended well-aligned N-doped carbon nanotubes was also prepared. The free-standing film can be transferred easily to other substrates, which would promote their applications in different fields.

  18. Direct Synthesis of Carbon Nanotube Field Emitters on Metal Substrate for Open-Type X-ray Source in Medical Imaging.

    Science.gov (United States)

    Gupta, Amar Prasad; Park, Sangjun; Yeo, Seung Jun; Jung, Jaeik; Cho, Chonggil; Paik, Sang Hyun; Park, Hunkuk; Cho, Young Chul; Kim, Seung Hoon; Shin, Ji Hoon; Ahn, Jeung Sun; Ryu, Jehwang

    2017-07-29

    We report the design, fabrication and characterization of a carbon nanotube enabled open-type X-ray system for medical imaging. We directly grew the carbon nanotubes used as electron emitter for electron gun on a non-polished raw metallic rectangular-rounded substrate with an area of 0.1377 cm² through a plasma enhanced chemical vapor deposition system. The stable field emission properties with triode electrodes after electrical aging treatment showed an anode emission current of 0.63 mA at a gate field of 7.51 V/μm. The 4.5-inch cubic shape open type X-ray system was developed consisting of an X-ray aperture, a vacuum part, an anode high voltage part, and a field emission electron gun including three electrodes with focusing, gate and cathode electrodes. Using this system, we obtained high-resolution X-ray images accelerated at 42-70 kV voltage by digital switching control between emitter and ground electrode.

  19. Direct Synthesis of Carbon Nanotube Field Emitters on Metal Substrate for Open-Type X-ray Source in Medical Imaging

    Directory of Open Access Journals (Sweden)

    Amar Prasad Gupta

    2017-07-01

    Full Text Available We report the design, fabrication and characterization of a carbon nanotube enabled open-type X-ray system for medical imaging. We directly grew the carbon nanotubes used as electron emitter for electron gun on a non-polished raw metallic rectangular-rounded substrate with an area of 0.1377 cm2 through a plasma enhanced chemical vapor deposition system. The stable field emission properties with triode electrodes after electrical aging treatment showed an anode emission current of 0.63 mA at a gate field of 7.51 V/μm. The 4.5-inch cubic shape open type X-ray system was developed consisting of an X-ray aperture, a vacuum part, an anode high voltage part, and a field emission electron gun including three electrodes with focusing, gate and cathode electrodes. Using this system, we obtained high-resolution X-ray images accelerated at 42–70 kV voltage by digital switching control between emitter and ground electrode.

  20. Synthesis and enhanced field-emission of thin-walled, open-ended, and well-aligned N-doped carbon nanotubes.

    Science.gov (United States)

    Cui, Tongxiang; Lv, Ruitao; Kang, Feiyu; Hu, Qiang; Gu, Jialin; Wang, Kunlin; Wu, Dehai

    2010-03-31

    Thin-walled, open-ended, and well-aligned N-doped carbon nanotubes (CNTs) on the quartz slides were synthesized by using acetonitrile as carbon sources. As-obtained products possess large thin-walled index (TWI, defined as the ratio of inner diameter and wall thickness of a CNT). The effect of temperature on the growth of CNTs using acetonitrile as the carbon source was also investigated. It is found that the diameter, the TWI of CNTs increase and the Fe encapsulation in CNTs decreases as the growth temperature rises in the range of 780-860°C. When the growth temperature is kept at 860°C, CNTs with TWI = 6.2 can be obtained. It was found that the filed-emission properties became better as CNT growth temperatures increased from 780 to 860°C. The lowest turn-on and threshold field was 0.27 and 0.49 V/μm, respectively. And the best field-enhancement factors reached 1.09 × 105, which is significantly improved about an order of magnitude compared with previous reports. In this study, about 30 × 50 mm2 free-standing film of thin-walled open-ended well-aligned N-doped carbon nanotubes was also prepared. The free-standing film can be transferred easily to other substrates, which would promote their applications in different fields.

  1. Degradation of male and female rufous-and-white wren songs in a tropical forest: effects of sex, perch height, and habitat

    DEFF Research Database (Denmark)

    Barker, Nicole K.S.; Dabelsteen, Torben; Mennill, Daniel J.

    2009-01-01

    of these factors on excess attenuation, signal-to-noise ratio, tail-to-signal ratio, and blur ratio of male and female songs. As expected, song degradation increased with distance between signaller and receiver. Songs transmitted best when emitted from moderate heights (5-7 m), although this pattern varied....... Rufous-and-white wren songs appeared more attenuated in open field than forest habitats, but microhabitat conditions within the forests exerted a strong influence on song degradation. These findings match previous studies showing an effect of distance, song post height, and habitat, but contrast...

  2. About Frequency Characteristics of Electric Fields of Cylindrical Piezoceramic Antenna with Screen in the Form of an Open Ring Layer

    Directory of Open Access Journals (Sweden)

    O.I. Nyzhnyk

    2016-11-01

    Full Text Available According to rigorous method of “related” fields the analytical expressions to describe electric fields of cylindrical piezoceramic radiators, forming flat echolocation system was obtained. As a result of numerical analysis the quantity relations and the features of frequency characteristics of the electric current and the input impedance of plane system was obtained and their physical interpretation was given. It is shown that the radial symmetry of the electric load system of radiators and the loss of radial symmetry of the acoustic load of radiators in this system violates the identity of the electronic processes occurring in the piezoelectric elements in the system.

  3. Direct Synthesis of Carbon Nanotube Field Emitters on Metal Substrate for Open-Type X-ray Source in Medical Imaging

    OpenAIRE

    Amar Prasad Gupta; Sangjun Park; Seung Jun Yeo; Jaeik Jung; Chonggil Cho; Sang Hyun Paik; Hunkuk Park; Young Chul Cho; Seung Hoon Kim; Ji Hoon Shin; Jeung Sun Ahn; Jehwang Ryu

    2017-01-01

    We report the design, fabrication and characterization of a carbon nanotube enabled open-type X-ray system for medical imaging. We directly grew the carbon nanotubes used as electron emitter for electron gun on a non-polished raw metallic rectangular-rounded substrate with an area of 0.1377 cm2 through a plasma enhanced chemical vapor deposition system. The stable field emission properties with triode electrodes after electrical aging treatment showed an anode emission current of 0.63 mA at a...

  4. [The effect of ethanol consumption by dams on the offspring locomotion in the open field test and carboxypeptidase activities in the rat brain and adrenal medulla].

    Science.gov (United States)

    Mukhina, E S; Saldaev, D A; Vernigora, A N; Gengin, M T

    2005-03-01

    Consumption of dams ethanol increased the posterity locomotion activity in open field test. The increase in female rats was higher then in male ones. Differences in the carboxypeptidase H and PMSF-inhibited carboxypeptidase activities between the brain regions and adrenal medulla of prenatally exposed to ethanol and intact rats were found. The changing of enzyme activities in female rats was higher then in male ones. It is possible that dams ethanol consumption induced profound changes in locomotion mediated, at least partially, by changes in the rate of proteolytic processing of neuropeptide precursors.

  5. 基于OpenGL的破片战斗部威力场可视化仿真%Visual Simulation of the Killing Field of Fragment Warhead Based on OpenGL

    Institute of Scientific and Technical Information of China (English)

    廖莎莎; 吴成

    2011-01-01

    Based on the movement law and characteristic of fragment power field, the models to simulate fragment velocity, azimuth angle and direction angel were built. Applying Visual C+ + development environment and OpenGL graphics library, 3D dynamic visualization simulation platform of fragment warhead was developed. The result shows that the simulation platform can recapture the process of fragment movement with different structure parameters and detonation modes. Also it is suitable in general to the initial design and parameter optimization of conventional fragment warhead.%针对破片战斗部的运动规律和飞散特点,建立破片速度、飞散方位角和飞散方向角的仿真模型,应用Visual C++开发环境和OpenGL图形库开发了破片战斗部威力场视景仿真平台.结果表明,利用该仿真平台能够形象直观地再现不同结构参数和起爆方式下破片飞散的动态过程,具有一定范围的适用性,可以满足常规破片战斗部结构设计、参数优化和性能计算等需要.

  6. The Open

    Directory of Open Access Journals (Sweden)

    Saitya Brata Das

    2009-12-01

    Full Text Available In the Open darkness and light, remembrance and oblivion, coming into existence and disappearing in death play their originary co-belonging, or co-figuration. Existence belongs to this opening and is exposed to its coming to presence: it is on the basis of this originary opening, this originary historical which is revealed to this mortal being called ‘man,’ on the basis of this revelation, man founds something like politics and history. There thus comes into existence out of this freedom, out of this “play space”2, this field called ‘polis’3 where there takes place war and festival, where historical revolutions tear apart history, brings ruptures and discontinuities in the very mode of his existence, where man seeks the foundation of his own foundation (which is his metaphysical task , where occurs the dialectics of negativity between man and man, where man puts at stake his own death, his own dissolution, and by the power of his own dissolution stands in relation to the total world that he seeks to dominate. This means that man’s attempts to metaphysically found his own political and historical existence must presuppose a far more originary non-foundation, the differentiating revealing of the open, the ungrounded spacing play, or playing space of natality and mortality.

  7. A Systematic Mapping on the Learning Analytics Field and Its Analysis in the Massive Open Online Courses Context

    Science.gov (United States)

    Moissa, Barbara; Gasparini, Isabela; Kemczinski, Avanilde

    2015-01-01

    Learning Analytics (LA) is a field that aims to optimize learning through the study of dynamical processes occurring in the students' context. It covers the measurement, collection, analysis and reporting of data about students and their contexts. This study aims at surveying existing research on LA to identify approaches, topics, and needs for…

  8. Characterization of an electronic system for Image acquisition portal to open field dosimetry; Caracterizacao de um sistema eletronico de aquisicao de imagem portal para dosimetria em radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Barbi, Gustavo L.; Oliveira, Harley F.; Bertucci, Edenyse C.; Amaral, Leonardo L.; Borges, Leandro F., E-mail: gustavobarbi@usp.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Hospital das Clinicas. Centro de Ciencias das Imagens e Fisica Medica

    2012-08-15

    The objective was to characterize and enable an electronic portal imaging device (EPID) to use like a portal dosimetry device - PDI, in non-transit mode, without interposition of scattering between the beam and EPID for measurement to open fields. The images as well as the DICOM header data are extracted from software ImageJ and the information are used in the basic algorithm for converting pixel to dose. The linearity and reproducibility of response were analyzed, and the maximum deviation found of 2,3% to 800 monitor units (MU) for linearity and -0,9% for reproducibility of signal measured daily. A 512x512 matrix with a resolution of 0,8mm was established to restore the shape of beam from the image. The field size dependence was evaluated, by obtaining the ratio of total scattering of ionization chamber and EPID. Finally, a calibration factor of 28470.88{+-}170.73 pixel/cGy was established for the central area of the image. Comparative analyzes between the PDI, radiochromic film and array of ionization chambers (MatriXX) showed good agreement for fields greater then 5 x 5 cm{sup 2} to reestablishment of form field and dose, however, for fields between 3x3 cm{sup 2} and 5x5 cm{sup 2}, the agreement to shape of beam was best established by film. (author)

  9. Behavior of near-field dilution of thermal buoyant jet discharged horizontally in compound open-channel

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The RNG к-ε model considering the buoyancy effect,which is solved by the hybrid finite analytic method,is used to simulate the mixture of the horizontal round thermal buoyant jet in compound open channel flow.The mixing features near the spout and flowing characteristic of the secondary currents are studied by numerical simulation.Meanwhile,(1) the distribution of the measured isovels for stream-wise velocity,(2) secondary currents,(3) the distribution of the measured isovels for temperature of typical cross-section near the spout,were obtained by the three-dimensional Micro ADV and the Temperature measuring device.Compared with experimental data,the RNG к-εmodel based on buoyancy effect can preferably simulate the jet which performs the bifurcation phenomenon,jet reattachment (Conada effect) and beach secondary currents phenomenon with the effect of ambient flow,buoyancy,and secondary currents of compound section and so on.

  10. CURious Variables Experiment (CURVE). CCD Photometry and Variable Stars in the field of open cluster NGC 637

    CERN Document Server

    Pietrukowicz, P; Wisniewski, M; Kedzierski, P; Mularczyk, K; Zloczewski, K; Starczewski, S; Szaruga, K

    2006-01-01

    We present VI photometry for the open cluster NGC 637 which is located in the Cassiopeia region. Morphology of cluster color-magnitude diagram indicates that it is a young object with age of a few million years. The apparent distance modulus of the cluster is 13.9<(m-M)_V<14.3, while reddening is 0.69

  11. Carpinteria salt marsh habitat polygons

    Science.gov (United States)

    Lafferty, Kevin D.; Dunham, Eleca J.; Mancini, Frank T.; Stewart, Tara E.; Hechinger, Ryan F.

    2017-01-01

    We identified five common habitat types in Carpinteria Salt Marsh: channels, pans (flats), marsh, salt flat and upland.  We then drew polygons around each habitat type identified from a registered and orthorectified aerial photograph and created a GIS shapefile. Polygons were ground-truthed in the field. From these habitat polygons, one can use GIS applications to estimate the area of each habitat type in this estuary. These data support the following publications: Kuris, Armand M., et al. "Ecosystem energetic implications of parasite and free-living biomass in three estuaries." Nature 454.7203 (2008): 515-518.Hechinger, Ryan F., Kevin D. Lafferty, Andy P. Dobson, James H. Brown, and Armand M. Kuris. "A common scaling rule for abundance, energetics, and production of parasitic and free-living species." Science 333, no. 6041 (2011): 445-448.Hechinger, Ryan F., Kevin D. Lafferty, John P. McLaughlin, Brian L. Fredensborg, Todd C. Huspeni, Julio Lorda, Parwant K. Sandhu et al. "Food webs including parasites, biomass, body sizes, and life stages for three California/Baja California estuaries." Ecology 92, no. 3 (2011): 791-791.Buck, J.C., Hechinger, R.F., Wood, A.C., Stewart, T.E., Kuris, A.M., and Lafferty, K.D., "Host density increases parasite recruitment but decreases host risk in a snail-trematode system." Manuscript submitted for publication. Lafferty, K.D., Stewart, T.E., and Hechinger, R.F. (in press). Bird distribution surveys at Carpinteria Salt Marsh, California USA, January 2012 to March 2013: U.S. Geological Survey data release, http://dx.doi.org/10.5066/F7F47M95. 

  12. Green Turtle Critical Habitat

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data represent the critical habitat for green turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations.

  13. VT Wildlife Linkage Habitat

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The Wildlife Linkage Habitat Analysis uses landscape scale data to identify or predict the location of potentially significant wildlife linkage...

  14. Designated Critical Habitat

    Data.gov (United States)

    Kansas Data Access and Support Center — Critical habitats include those areas documented as currently supporting self-sustaining populations of any threatened or endangered species of wildlife as well as...

  15. Habitats, activities, and signs

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh; Brynskov, Martin

    2004-01-01

    Digital habitats is a framework for designing and modeling environments for activities that involve mobile and embedded computing systems. This paper 1) introduces the basic concepts of the framework, i.e. activity, thematic role, and the three ‘dimensions’ of a habitat: physical, informational, ......, and pragmatic, 2) proposes a notation, and 3) sketches a method and exemplifies areas of application using authentic cases from hospital work, primary school education, the maritime domain, and other areas......Digital habitats is a framework for designing and modeling environments for activities that involve mobile and embedded computing systems. This paper 1) introduces the basic concepts of the framework, i.e. activity, thematic role, and the three ‘dimensions’ of a habitat: physical, informational...

  16. Green Turtle Critical Habitat

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data represent the critical habitat for green turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations.

  17. Right Whale Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Right Whale as designated by Federal Register Vol. 59, No. 28805, May 19, 1993, Rules and Regulations.

  18. Habitat Mapping Camera (HABCAM)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset entails imagery collected using the HabCam towed underwater vehicle and annotated data on objects or habitats in the images and notes on image...

  19. Green Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for green turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations.

  20. Critical Habitat Designations

    Data.gov (United States)

    Department of Homeland Security — The Endangered Species Act (ESA) requires the Federal government to designate 'critical habitat' for any species it lists under the ESA. This dataset combines both...

  1. Johnsons Seagrass Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Johnson's Seagrass as designated by Federal Register Vol. 65, No. 66, Wednesday, April 5, 2000, Rules and Regulations.

  2. Smalltooth Sawfish Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for smalltooth sawfish (Pristis pectinatat) as designated by 74 FR 45353, September 2, 2009, Rules and Regulations.

  3. The p53 codon 72 PRO/PRO genotype may be associated with initial central visual field defects in caucasians with primary open angle glaucoma.

    Directory of Open Access Journals (Sweden)

    Janey L Wiggs

    Full Text Available BACKGROUND: Loss of vision in glaucoma is due to apoptotic retinal ganglion cell loss. While p53 modulates apoptosis, gene association studies between p53 variants and glaucoma have been inconsistent. In this study we evaluate the association between a p53 variant functionally known to influence apoptosis (codon 72 Pro/Arg and the subset of primary open angle glaucoma (POAG patients with early loss of central visual field. METHODS: Genotypes for the p53 codon 72 polymorphism (Pro/Arg were obtained for 264 POAG patients and 400 controls from the U.S. and in replication studies for 308 POAG patients and 178 controls from Australia (GIST. The glaucoma patients were divided into two groups according to location of initial visual field defect (either paracentral or peripheral. All cases and controls were Caucasian with European ancestry. RESULTS: The p53-PRO/PRO genotype was more frequent in the U.S. POAG patients with early visual field defects in the paracentral regions compared with those in the peripheral regions or control group (p=2.7 × 10(-5. We replicated this finding in the GIST cohort (p  =7.3 × 10(-3, and in the pooled sample (p=6.6 × 10(-7 and in a meta-analysis of both the US and GIST datasets (1.3 × 10(-6, OR 2.17 (1.58-2.98 for the PRO allele. CONCLUSIONS: These results suggest that the p53 codon 72 PRO/PRO genotype is potentially associated with early paracentral visual field defects in primary open-angle glaucoma patients.

  4. Smartphone-based distributed data collection enables rapid assessment of shorebird habitat suitability

    Science.gov (United States)

    Thieler, E. Robert; Zeigler, Sara; Winslow, Luke; Hines, Megan K.; Read, Jordan S.; Walker, Jordan I.

    2016-01-01

    Understanding and managing dynamic coastal landscapes for beach-dependent species requires biological and geological data across the range of relevant environments and habitats. It is difficult to acquire such information; data often have limited focus due to resource constraints, are collected by non-specialists, or lack observational uniformity. We developed an open-source smartphone application called iPlover that addresses these difficulties in collecting biogeomorphic information at piping plover (Charadrius melodus) nest sites on coastal beaches. This paper describes iPlover development and evaluates data quality and utility following two years of collection (n = 1799 data points over 1500 km of coast between Maine and North Carolina, USA). We found strong agreement between field user and expert assessments and high model skill when data were used for habitat suitability prediction. Methods used here to develop and deploy a distributed data collection system have broad applicability to interdisciplinary environmental monitoring and modeling.

  5. Advective Heat Transport in an Unconfined Aquifer Induced by the Field Injection of an Open-Loop Groundwater Heat Pump

    Directory of Open Access Journals (Sweden)

    Stefano L. Russo

    2010-01-01

    Full Text Available Problem statement: The increasing diffusion of low-enthalpy geothermal open-loop Groundwater Heat Pumps (GWHP providing buildings air conditioning requires a careful assessment of the overall effects on groundwater system, especially in the urban areas. The impact on the groundwater temperature in the surrounding area of the re-injection well is directly linked to the aquifer properties. Physical processes affecting heat transport within an aquifer include advection (or convection and hydrodynamic thermodispersion (diffusion and mechanical dispersion. If the groundwater flows, the advective components tend to dominate the heat transfer process within the aquifer and the diffusion can be considered negligible. This study illustrates the experimental results derived from the groundwater monitoring in the surrounding area of an injection well connected to an open-loop GWHP plant which has been installed in the "Politecnico di Torino" (NW Italy for cooling some of the university buildings. Groundwater pumping and injection interfere only with the upper unconfined aquifer. Approach: After the description of the hydrogeological setting the authors examined the data deriving from multiparameter probes installed inside the pumping well (P2, the injection well (P4 and a downgradient piezometer (S2. Data refers to the summer 2009. To control the aquifer thermal stratification some multi-temporal temperature logs have been performed in the S2. Results: After the injection of warm water in P4 the plume arrived after 30 days in the S2. That delay is compatible with the calculated plume migration velocity (1.27 m d-1 and their respective distance (35 m. The natural temperature in the aquifer due to the switching-off of the GWHP plant has been reached after two month. The Electrical Conductivity (EC values tend to vary out of phase with the temperature. The temperature logs in the S2 highlighted a thermal stratification in the aquifer due to a low vertical

  6. Results of first field tests of the improved open-path and enclosed models of CO2 and H2O flux measurements systems

    Science.gov (United States)

    Begashaw, Israel; Fratini, Gerardo; Griessbaum, Frank; Kathilankal, James; Xu, Liukang; Franz, Daniela; Joseph, Everett; Larmanou, Eric; Miller, Scott; Papale, Dario; Sabbatini, Simone; Sachs, Torsten; Sakai, Ricardo; McDermitt, Dayle; Burba, George

    2016-04-01

    In 2014-2015, improved open-path and enclosed-path flux measurement systems were developed, based on established LI-7500A and LI-7200 gas analyzer models, with the focus on improving stability in the presence of contamination, refining temperature control and compensation, and providing more accurate gas concentration measurements. In addition to optical and electronic redesign, both systems incorporate automated on-site flux calculations using EddyPro® software run by a weatherized remotely-accessible microcomputer, SmartFlux 2, with fully digital inputs. The ultimate goal of such development was to reduce errors in CO2 and H2O hourly fluxes and in long-term carbon and water budgets. Field tests of both systems were conducted over six periods, each 5-14 months long, at 6 sites with diverse environments, setups, and types of contamination, using 26 gas analyzers. The open-path LI-7500RS system performed significantly better than the original LI-7500A model in terms of contamination-related drifts in mean concentrations. Improvements in CO2 drifts were strong, with RS models often drifting few-to-tens of times less than the original. Improvements in H2O contamination-related drifts were particularly significant, with modified models often drifting many tens of times less than the original. The enclosed-path LI-7200RS system performed substantially better than the original LI-7200 in terms of the drifts in H2O, sometimes drifting few-to-tens of times less than the original. Improvements in CO2 contamination-related drifts were modest, being similar or just a bit better than the original. Results from field tests suggest that both RS systems can help improve flux data coverage and potentially reduce site maintenance: (i) Frequency of cleaning and site visits for service and maintenance should decrease, especially for the open-path design (ii) Amount of highest quality data with smallest error bars on fluxes is expected to increase for both open-path and enclosed

  7. Habitat-specific population growth of a farmland bird.

    Directory of Open Access Journals (Sweden)

    Debora Arlt

    Full Text Available BACKGROUND: To assess population persistence of species living in heterogeneous landscapes, the effects of habitat on reproduction and survival have to be investigated. METHODOLOGY/PRINCIPAL FINDINGS: We used a matrix population model to estimate habitat-specific population growth rates for a population of northern wheatears Oenanthe oenanthe breeding in farmland consisting of a mosaic of distinct habitat (land use types. Based on extensive long-term data on reproduction and survival, habitats characterised by tall field layers (spring- and autumn-sown crop fields, ungrazed grasslands displayed negative stochastic population growth rates (log lambda(s: -0.332, -0.429, -0.168, respectively, that were markedly lower than growth rates of habitats characterised by permanently short field layers (pastures grazed by cattle or horses, and farmyards, log lambda(s: -0.056, +0.081, -0.059. Although habitats differed with respect to reproductive performance, differences in habitat-specific population growth were largely due to differences in adult and first-year survival rates, as shown by a life table response experiment (LTRE. CONCLUSIONS/SIGNIFICANCE: Our results show that estimation of survival rates is important for realistic assessments of habitat quality. Results also indicate that grazed grasslands and farmyards may act as source habitats, whereas crop fields and ungrazed grasslands with tall field layers may act as sink habitats. We suggest that the strong decline of northern wheatears in Swedish farmland may be linked to the corresponding observed loss of high quality breeding habitat, i.e. grazed semi-natural grasslands.

  8. Galactic Globular and Open Clusters in the Sloan Digital Sky Survey. I. Crowded Field Photometry and Cluster Fiducial Sequences in ugriz

    CERN Document Server

    An, Deokkeun; Clem, James L; Yanny, Brian; Rockosi, Constance M; Morrison, Heather L; Harding, Paul; Gunn, James E; Prieto, Carlos Allende; Beers, Timothy C; Cudworth, Kyle M; Ivans, Inese I; Ivezic, Zeljko; Lee, Young Sun; Lupton, Robert H; Bizyaev, Dmitry; Brewington, Howard; Malanushenko, Elena; Malanushenko, Viktor; Oravetz, Dan; Pan, Kaike; Simmons, Audrey; Snedden, Stephanie; Watters, Shannon; York, Donald G

    2008-01-01

    We present photometry for globular and open cluster stars observed with the Sloan Digital Sky Survey (SDSS). In order to exploit over 100 million stellar objects with r < 22.5 mag observed by SDSS, we need to understand the characteristics of stars in the SDSS ugriz filters. While star clusters provide important calibration samples for stellar colors, the regions close to globular clusters, where the fraction of field stars is smallest, are too crowded for the standard SDSS photometric pipeline to process. To complement the SDSS imaging survey, we reduce the SDSS imaging data for crowded cluster fields using the DAOPHOT/ALLFRAME suite of programs and present photometry for 17 globular clusters and 3 open clusters in a SDSS value-added catalog. Our photometry and cluster fiducial sequences are on the native SDSS 2.5-meter ugriz photometric system, and the fiducial sequences can be directly applied to the SDSS photometry without relying upon any transformations. Model photometry for red giant branch and main...

  9. [Effect of genotype and day or night time of testing on mice behavior in the light-dark box and the open-field tests].

    Science.gov (United States)

    Morozova, M V; Kulikov, A V

    2010-01-01

    The light-dark box (LDB) and the open-field (OF) tests are widespread experimental models for studying locomotion and anxiety in laboratory rats and mice. The fact that rodents are nocturnal animals and more active at night raises a critical question of whether behavioral experiments carried out in the light phase are methodologically correct. Parameters of behavior of four mouse strains (C57BL/6J, DBA2/J, AKR/J and CBA/LacJ) in the light-dark box and open-field tests in the light and dark phases were compared. No significant influence of the phase of testing on anxiety in LDB and OF tests was revealed. In the OF test CBA mice showed increased locomotor activity, whereas AKR and C57BL/6 mice showed increased defecation in the dark phase. It was concluded that: 1) the phase of testing is not crucial for the expression of anxiety in LDB and OF; 2) the sensitivity to the phase of testing depends on the genotype; 3) the indices of behavior in the genotypes sensitive to the phase of testing (locomotion in the CBA and defecation in the AKR and C57BL/6 mouse strains) are increased in the dark phase.

  10. [Comparative analysis of the maternal motivation expression in WAG/Rij and Wistar rats in the place preference and open field tests].

    Science.gov (United States)

    Dobriakova, Iu V; Tanaeva, K K; Dubynin, V A; Sarkisova, K Iu

    2014-01-01

    Maternal behavior in females of WAG/Rij and Wistar rats was compared in the place preference test from 2 to 8 days after delivery, as well as in the open field test from 4 to 6 days after delivery. In females of WAG/Rij rats compared with females of Wistar rats weaker expression of maternal motivation has been revealed in both tests: they spend less time in the compartment associated with pups. Moreover, in females of WAG/Rij rats, number of approaches to pups, number of pup-carryings and time spent with pups (time of contacts) were less than in females of Wistar rats. Reduced maternal motivation in females of WAG/Rij rats in the place preference test persisted in repeated testing, while in the open field test it was detected only in the first testing, indicating higher reliability of the place preference test for revealing inter-strain differences in the expression of maternal motivation. It is supposed that weaker expression of maternal behavior and preference is due to hypo-function of the mesolimbic dopaminergic bran system in WAG/Rij rats as a genetic model of depression associated with absence epilepsy.

  11. Role of thirst and visual barriers in the differential behavior displayed by streptozotocin-treated rats in the elevated plus-maze and the open field test.

    Science.gov (United States)

    Rebolledo-Solleiro, Daniela; Crespo-Ramírez, Minerva; Roldán-Roldán, Gabriel; Hiriart, Marcia; Pérez de la Mora, Miguel

    2013-08-15

    Conflicting results have been obtained by several groups when studying the effects of streptozotocin (STZ)-treated rats in the elevated plus-maze (EPM). Since thirst is a prominent feature in STZ-induced diabetic-like condition, we studied whether the walls of the closed arms of the EPM, by limiting the search for water in the environment, may contribute to the observed differential behavioral outcomes. The aim of this study was to ascertain whether visual barriers within the EPM have an influence on the behavior of STZ-treated rats in this test of anxiety. A striking similarity between STZ-treated (50 mg/kg, i.p., in two consecutive days) and water deprived rats (72 h) was found in exploratory behavior in the EPM, showing an anxiolytic-like profile. However the anxiolytic response of STZ-treated rats exposed to the EPM shifts into an anxiogenic profile when they are subsequently tested in the open-field test, which unlike the EPM is devoid of visual barriers. Likewise, water deprived rats (72 h) also showed an anxiogenic profile when they were exposed to the open-field test. Our results indicate that experimental outcomes based on EPM observations can be misleading when studying physiological or pathological conditions, e.g. diabetes, in which thirst may increase exploratory behavior.

  12. Is Habitat Preference Associated with Locomotor Performance in Multiocellated Racerunners (Eremias multiocellata) from a Desert Steppe?

    Institute of Scientific and Technical Information of China (English)

    Junhuai BI; Yang WANG; Shuran LI; Zhigao ZENG

    2015-01-01

    Locomotor performance in lizards is strongly affected by structural habitat. Understanding this relationship allows us to predict species distributions across habitat types. However, little information is available about the ecological role of the locomotion of multiocellated racerunner (Eremias multiocellata) in the desert steppe ecosystem of Inner Mongolia, China. Herein, we studied the effects of habitat structure on the locomotor performance of this lizard species in the field. We found that the sprint speed of this lizard declined significantly with increasing vegetation coverage. Manipulative experiments were further conducted to examine the effects of branch barriers and surface substrates on the sprint speed of the lizard. We found that the sprint speed was significantly influenced by the surface substrates and branch barriers, and there were no interactions between them. Branch barriers impeded sprint speed, and E. multiocellata showed better locomotor performance on sandy rather than loamy substrates. Our results indicate that E. multiocellata tends to occupy open areas with sandy substrates, but its locomotor performance is not closely associated with habitat preference.

  13. Assessment of mouse anxiety-like behavior in the light-dark box and open-field arena: role of equipment and procedure.

    Science.gov (United States)

    Kulesskaya, Natalia; Voikar, Vootele

    2014-06-22

    Light-dark box and open field are conventional tests for assessment of anxiety-like behavior in the laboratory mice, based on approach-avoidance conflict. However, except the basic principles, variations in the equipment and procedures are very common. Therefore, contribution of certain methodological issues in different settings was investigated. Three inbred strains (C57BL/6, 129/Sv, DBA/2) and one outbred stock (ICR) of mice were used in the experiments. An effect of initial placement of mice either in the light or dark compartment was studied in the light-dark test. Moreover, two tracking systems were applied - position of the animals was detected either by infrared sensors in square box (1/2 dark) or by videotracking in rectangular box (1/3 dark). Both approaches revealed robust and consistent strain differences in the exploratory behavior. In general, C57BL/6 and ICR mice showed reduced anxiety-like behavior as compared to 129/Sv and DBA/2 strains. However, the latter two strains differed markedly in their behavior. DBA/2 mice displayed high avoidance of the light compartment accompanied by thigmotaxis, whereas the hypoactive 129 mice spent a significant proportion of time in risk-assessment behavior at the opening between two compartments. Starting from the light side increased the time spent in the light compartment and reduced the latency to the first transition. In the open field arena, black floor promoted exploratory behavior - increased time and distance in the center and increased rearing compared to white floor. In conclusion, modifications of the apparatus and procedure had significant effects on approach-avoidance behavior in general whereas the strain rankings remained unaffected.

  14. Experimental and numerical investigation of the flow field in the gradual transition of rectangular to trapezoidal open channels

    Directory of Open Access Journals (Sweden)

    Adel Asnaashari

    2016-01-01

    Full Text Available Transitions are structures that can change geometry and flow velocity through varying the cross-sections of their channels. Under subcritical flow and steady flow conditions, it is necessary to reduce the flow velocity gradually due to increasing water pressure and adverse pressure gradients. Due to the separation of flow and subsequent eddy formation, a significant energy loss is incurred along the transition. This study presents the results of experimental investigations of the subcritical flow along the expansive transition of rectangular to trapezoidal channels. A numerical simulation was developed using a finite volume of fluid (VOF method with a Reynolds stress turbulence model. Water surface profiles and velocity distributions of flow through the transition were measured experimentally and compared with the numerical results. A good agreement between the experimental and numerical model results showed that the Reynolds model and VOF method are capable of simulating the hydraulic flow in open channel transitions. Also, the efficiency of the transition and coefficient of energy head loss were calculated. The results show that with an increasing upstream Froude number, the efficiency of the transition and coefficient of energy head loss decrease and increase, respectively. The results also show the ability of numerical simulation to simulate the flow separation zones and secondary current along the transition for different inlet discharges.

  15. The location of the open-closed magnetic field line boundary in the dawn sector auroral ionosphere

    Directory of Open Access Journals (Sweden)

    J. A. Wild

    2004-11-01

    Full Text Available As a measure of the degree of coupling between the solar wind-magnetosphere-ionosphere systems, the rate at which the size of the polar cap (the region corresponding to ionospheric termini of open magnetic flux tubes varies is of prime importance. However, a reliable technique by which the extent of the polar cap might be routinely monitored has yet to be developed. Current techniques provide particularly ambiguous indications of the polar cap boundary in the dawn sector. We present a case study of space- and ground-based observations of the dawn-sector auroral zone and attempt to determine the location of the polar cap boundary using multi-wavelength observations of the ultraviolet aurora (made by the IMAGE FUV imager, precipitating particle measurements (recorded by the FAST, DMSP, and Cluster 1 and 3 satellites, and SuperDARN HF radar observations of the ionospheric Doppler spectral width boundary. We conclude that in the dawn sector, during the interval presented, neither the poleward edge of the wideband auroral UV emission (140-180nm nor the Doppler spectral width boundary were trustworthy indicators of the polar cap boundary location, while narrow band UV emissions in the range 130-140nm appear to be much more reliable.

  16. Eder Acquisition 2007 Habitat Evaluation Procedures Report.

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, Paul R.

    2008-01-01

    A habitat evaluation procedures (HEP) analysis was conducted on the Eder acquisition in July 2007 to determine how many protection habitat units to credit Bonneville Power Administration (BPA) for providing funds to acquire the project site as partial mitigation for habitat losses associated with construction of Grand Coulee and Chief Joseph Dams. Baseline HEP surveys generated 3,857.64 habitat units or 1.16 HUs per acre. HEP surveys also served to document general habitat conditions. Survey results indicated that the herbaceous plant community lacked forbs species, which may be due to both livestock grazing and the late timing of the surveys. Moreover, the herbaceous plant community lacked structure based on lower than expected visual obstruction readings (VOR); likely a direct result of livestock impacts. In addition, introduced herbaceous vegetation including cultivated pasture grasses, e.g. crested wheatgrass and/or invader species such as cheatgrass and mustard, were present on most areas surveyed. The shrub element within the shrubsteppe cover type was generally a mosaic of moderate to dense shrubby areas interspersed with open grassland communities while the 'steppe' component was almost entirely devoid of shrubs. Riparian shrub and forest areas were somewhat stressed by livestock. Moreover, shrub and tree communities along the lower reaches of Nine Mile Creek suffered from lack of water due to the previous landowners 'piping' water out of the stream channel.

  17. Exposure to an open-field arena increases c-Fos expression in a subpopulation of neurons in the dorsal raphe nucleus, including neurons projecting to the basolateral amygdaloid complex

    DEFF Research Database (Denmark)

    Hale, M.W.; Hay-Schmidt, A.; Mikkelsen, J.D.

    2008-01-01

    Serotonergic systems in the dorsal raphe nucleus are thought to play an important role in the regulation of anxiety states. To investigate responses of neurons in the dorsal raphe nucleus to a mild anxiety-related stimulus, we exposed rats to an open-field, under low-light or high-light conditions....... Treatment effects on c-Fos expression in serotonergic and non-serotonergic cells in the midbrain raphe nuclei were determined 2 h following open-field exposure or home cage control (CO) conditions. Rats tested under both light conditions responded with increases in c-Fos expression in serotonergic neurons...... within subdivisions of the midbrain raphe nuclei compared with CO rats. However, the total numbers of serotonergic neurons involved were small suggesting that exposure to the open-field may affect a subpopulation of serotonergic neurons. To determine if exposure to the open-field activates a subset...

  18. Configuration-averaged open shell ab initio method for crystal field levels and magnetic properties of lanthanide(III) complexes

    CERN Document Server

    Heuvel, Willem Van den; Soncini, Alessandro

    2015-01-01

    We present an ab initio methodology dedicated to the determination of the electronic structure and magnetic properties of ground and low-lying excited states, i.e., the crystal field levels, in lanthanide(III) complexes. Currently, the most popular and successful ab initio approach is the CASSCF/RASSI-SO method, consisting of the optimization of multiple complete active space self-consistent field (CASSCF) spin eigenfunctions, followed by full diagonalization of the spin--orbit coupling (SOC) Hamiltonian in the basis of the CASSCF spin states featuring spin-dependent orbitals. Based on two simple observations valid for Ln(III) complexes, namely: (i) CASSCF 4f atomic orbitals are expected to change very little when optimized for different multiconfigurational states belonging to the 4f-electronic configuration, (ii) due to strong SOC the total spin is not a good quantum number, we propose here an efficient ab initio strategy which completely avoids any multiconfigurational calculation, by optimizing a unique s...

  19. Alfv\\'en wave phase mixing in flows -- why over-dense solar coronal open magnetic field structures are cool?

    CERN Document Server

    Tsiklauri, D

    2015-01-01

    Our magnetohydrodynamic (MHD) simulations and analytical calculations show that, when a background flow is present, mathematical expressions for the Alfv\\'en wave (AW) damping via phase mixing are modified by a following substitution $C_A^\\prime(x) \\to C_A^\\prime(x)+V_0^\\prime(x)$, where $C_A$ and $V_0$ are AW phase and the flow speeds and prime denotes derivative in the direction across the background magnetic field. In uniform magnetic field and over-dense plasma structures, in which $C_A$ is smaller compared to surrounding plasma, the flow, that is confined to the structure, in the same direction as the AW, reduces the effect of phase mixing, because on the edges of the structure $C_A^\\prime$ and $V_0^\\prime$ have opposite sign. Thus, the wave damps via phase mixing {\\it slower} compared to the case without the flow. This is the consequence of the co-directional flow reducing the wave front stretching in the transverse direction. Although, the result is generic and is applicable to different laboratory or ...

  20. Evaluation of low back pain with low field open magnetic resonance imaging scanner in rural hospital of Southern India

    Directory of Open Access Journals (Sweden)

    Sadhanandham Shrinuvasan

    2016-01-01

    Full Text Available Background: Low back pain (LBP is the most common symptom which is associated with limitation of normal activities and work-related disability. Imaging techniques are often essential in making the correct diagnosis for prompt management. Plain Radiography though remain a first imaging modality, magnetic resonance imaging (MRI due to its inherent softtissue contrast resolution and lack of ionizing radiation remains invaluable modality in the evaluation of LBP. Aim: To find the common causes of LBP in different age groups and the role of MRI in detecting the spectrum of various pathological findings. Materials and Methods: This is a prospective study done in the Department of Radiodiagnosis during a period of 2 years from July 2013 to July 2015. The study population includes all the cases referred to our department with complaints of LBP. Patients with ferromagnetic metallic implants and uncooperative cases were excluded. HITACHI 0.4 Tesla open MRI machine was used for imaging. Results and Conclusion: This study involved a total of 235 cases. There were 121 males and 114 females. The age of the patient ranged from 21 to 68 years with an average of 41.3 years. Back pain was commonly observed in the third to fifth decade. The common causes for back pain are disc herniations (disc bulge - 35.3%, disc protrusion - 39.6%, disc extrusion - 7.2% accounting to 82.1%, followed by normal study (10.2%, vertebral collapse (traumatic - 2.1%, osteoporotic - 1.7%, infections (2.1%, and neoplasm (1.7%. MRI provides valuable information regarding the underlying causes of LBP, especially in disc and marrow pathology.