Social recognition is context dependent in single male prairie voles

PubMed Central

Zheng, Da-Jiang; Foley, Lauren; Rehman, Asad; Ophir, Alexander G.

2013-01-01

Single males might benefit from knowing the identity of neighbouring males when establishing and defending boundaries. Similarly, males should discriminate between individual females if this leads to more reproductive opportunities. Contextual social cues may alter the value of learning identity. Knowing the identity of competitors that intrude into an animal’s territory may be more salient than knowing the identity of individuals on whose territory an animal is trespassing. Hence, social and environmental context could affect social recognition in many ways. Here we test social recognition of socially monogamous single male prairie voles, Microtus ochrogaster. In experiment 1 we tested recognition of male or female conspecifics and found that males discriminated between different males but not between different females. In experiment 2 we asked whether recognition of males is influenced when males are tested in their own cage (familiar), in a clean cage (neutral) or in the home cage of another male (unfamiliar). Although focal males discriminated between male conspecifics in all three contexts, individual variation in recognition was lower when males were tested in their home cage (in the presence of familiar social cues) compared to when the context lacked social cues (neutral). Experiment 1 indicates that selective pressures may have operated to enhance male territorial behaviour and indiscriminate mate selection. Experiment 2 suggests that the presence of a conspecific cue heightens social recognition and that home-field advantages might extend to social cognition. Taken together, our results indicate social recognition depends on the social and possibly territorial context. PMID:24273328

Social recognition is context dependent in single male prairie voles.

PubMed

Zheng, Da-Jiang; Foley, Lauren; Rehman, Asad; Ophir, Alexander G

2013-11-01

Single males might benefit from knowing the identity of neighbouring males when establishing and defending boundaries. Similarly, males should discriminate between individual females if this leads to more reproductive opportunities. Contextual social cues may alter the value of learning identity. Knowing the identity of competitors that intrude into an animal's territory may be more salient than knowing the identity of individuals on whose territory an animal is trespassing. Hence, social and environmental context could affect social recognition in many ways. Here we test social recognition of socially monogamous single male prairie voles, Microtus ochrogaster . In experiment 1 we tested recognition of male or female conspecifics and found that males discriminated between different males but not between different females. In experiment 2 we asked whether recognition of males is influenced when males are tested in their own cage (familiar), in a clean cage (neutral) or in the home cage of another male (unfamiliar). Although focal males discriminated between male conspecifics in all three contexts, individual variation in recognition was lower when males were tested in their home cage (in the presence of familiar social cues) compared to when the context lacked social cues (neutral). Experiment 1 indicates that selective pressures may have operated to enhance male territorial behaviour and indiscriminate mate selection. Experiment 2 suggests that the presence of a conspecific cue heightens social recognition and that home-field advantages might extend to social cognition. Taken together, our results indicate social recognition depends on the social and possibly territorial context.

Does juvenile competition explain displacement of a native crayfish by an introduced crayfish?

USGS Publications Warehouse

Larson, E.R.; Magoulick, D.D.

2009-01-01

The coldwater crayfish Orconectes eupunctus is endemic to the Spring and Eleven Point Rivers of Arkansas and Missouri, and appears to have been displaced from a portion of its range by the recently introduced ringed crayfish Orconectes neglectus. We examined competition among juveniles as a potential mechanism for this crayfish species displacement through laboratory and field experiments. Orconectes eupunctus juveniles survived and grew in stream cages in their former range, implicating biotic interactions rather than habitat degradation in the displacement. Laboratory experiments revealed O. neglectus juveniles were dominant in the presence of limited food, whereas size rather than species determined occupancy of limited shelter. In a field competition experiment using stream cages, O. neglectus juveniles did not inhibit growth or reduce survival of O. eupunctus juveniles. Consequently, laboratory evidence of O. neglectus dominance did not correspond with competition under field conditions. Combined with previous studies examining the effects of O. neglectus on O. eupunctus, these results suggest that competition may not be a factor in this crayfish species displacement. Alternate mechanisms for the apparent displacement of O. eupunctus by O. neglectus, such as differential predation or reproductive interference, should be investigated. ?? 2008 Springer Science+Business Media B.V.

How the position of mussels at the intertidal lagoon affects their infection with the larvae of parasitic flatworms (Trematoda: Digenea): A combined laboratory and field experimental study

NASA Astrophysics Data System (ADS)

Nikolaev, Kirill E.; Prokofiev, Vladimir V.; Levakin, Ivan A.; Galaktionov, Kirill V.

2017-10-01

In the complex trematode life cycle, cercariae transmit infection from the first to the second intermediate host. These short-lived lecithotrophic larvae possess a complex of behavioural responses for finding and infecting the host. We studied strategies used by cercariae of Himasthla elongata and Cercaria parvicaudata (Renicola sp.) infecting mussels Mytilus edulis at the White Sea intertidal. Laboratory and field experiments were conducted in parallel. Geotactic response of cercariae was tested in an experimental chamber. Their distribution in nature was studied by counting larvae infecting mussels in cages installed in pairs (a ground and a suspended cage) in an intertidal lagoon. In the chamber H. elongata cercariae concentrated at the bottom, C. parvicaudata cercariae aged 1 h mostly concentrated near the surface and those aged 6 h sank to the bottom. A few larvae of both species ("evaders") showed behavioural patterns antithetic to the prevalent ones. Infection was the highest in mussels in ground cages. In suspended cages mussel infection with H. elongata cercariae was much lower than with C. parvicaudata cercariae. Our study confirmed that results of experiments on cercarial behaviour could be extrapolated to natural conditions. Cercariae of two species using the same intermediate hosts and co-occurring in a biotope implemented dramatically different strategies. This might be associated with differences in cercarial output by parthenitae groups. The presence of "evaders" might be useful for successful transmission. Our results indicate that mussels cultivated in suspended cultures are at the least risk of infection with trematode larvae.

Assessment of housing density, space allocation and social hierarchy of laboratory rats on behavioural measures of welfare.

PubMed

Barker, Timothy Hugh; George, Rebecca Peta; Howarth, Gordon Stanley; Whittaker, Alexandra Louise

2017-01-01

Minimum space allowances for laboratory rats are legislated based on weight and stocking rates, with the understanding that increased housing density encourages crowding stress. However, there is little evidence for these recommendations, especially when considering positive welfare outcomes. This study consisted of two experiments which investigated the effects of housing density (rats per cage), space allocation (surface area per rat) and social rank (dominance hierarchy) on the ability to perform simple behavioural tests. Male Sprague Dawley (SD) rats (n = 64) were allocated to either high-density (n = 8) or low-density (n = 8) cages. The second experiment investigated the effects of surface area. SD rats (n = 40) were housed in dyads in either the large (n = 10) or small (n = 10) cage. In both experiments, animals were tested on a judgment bias paradigm, with their responses to an ambiguous stimulus being ascribed as optimistic or pessimistic. Animals were also tested on open-field, novel-object recognition and social-interaction tests. Recordings were taken from 1700-2100h daily for rat observation and social rank establishment. Dominant animals responded with significantly more optimistic decisions compared to subordinates for both the housing density (p<0.001) and space allocation (p = 0.0015) experiment. Dominant animals responded with increased social affiliative behaviours in the social-interaction test, and spent more time in the centre of the open-field test for both experiments. No significance was detected between housing density or space allocation treatments. These findings suggest that social rank is a significantly greater modifier of affective state than either housing density or space allocation. This finding has not yet been reported and suggests that future drafts of housing guidelines should consider animal social status in addition to floor space requirements.

Assessment of housing density, space allocation and social hierarchy of laboratory rats on behavioural measures of welfare

PubMed Central

George, Rebecca Peta; Howarth, Gordon Stanley; Whittaker, Alexandra Louise

2017-01-01

Minimum space allowances for laboratory rats are legislated based on weight and stocking rates, with the understanding that increased housing density encourages crowding stress. However, there is little evidence for these recommendations, especially when considering positive welfare outcomes. This study consisted of two experiments which investigated the effects of housing density (rats per cage), space allocation (surface area per rat) and social rank (dominance hierarchy) on the ability to perform simple behavioural tests. Male Sprague Dawley (SD) rats (n = 64) were allocated to either high-density (n = 8) or low-density (n = 8) cages. The second experiment investigated the effects of surface area. SD rats (n = 40) were housed in dyads in either the large (n = 10) or small (n = 10) cage. In both experiments, animals were tested on a judgment bias paradigm, with their responses to an ambiguous stimulus being ascribed as optimistic or pessimistic. Animals were also tested on open-field, novel-object recognition and social-interaction tests. Recordings were taken from 1700-2100h daily for rat observation and social rank establishment. Dominant animals responded with significantly more optimistic decisions compared to subordinates for both the housing density (p<0.001) and space allocation (p = 0.0015) experiment. Dominant animals responded with increased social affiliative behaviours in the social-interaction test, and spent more time in the centre of the open-field test for both experiments. No significance was detected between housing density or space allocation treatments. These findings suggest that social rank is a significantly greater modifier of affective state than either housing density or space allocation. This finding has not yet been reported and suggests that future drafts of housing guidelines should consider animal social status in addition to floor space requirements. PMID:28926644

Plant quality and conspecific density effects on Anaphothrips obscurus (Thysanoptera: Thripidae) wing diphenism and population ecology.

PubMed

Reisig, Dominic D; Godfrey, Larry D; Marcum, Daniel B

2010-04-01

Factors that influence thysanopteran wing diphenism are not well known. In these studies, the impact of food quality, mediated through nitrogen addition, and conspecific density was explored on the wing diphenism of an herbivorous thrips species (Anaphothrips obscurus Müller) (Thysanoptera: Thripidae). In the first study, nitrogen was added to timothy grass (Phleum pretense L.) (Poales: Poaceae) transplants, and naturally occurring thrips populations were caged on the plants. Thrips abundance and foliar nutrients were assessed every 2 wk. A separate factorial experiment in growth chambers explored the impact of both plant nitrogen addition and thrips abundance on wing diphenism. Thrips density was manipulated by adding either 3 or 40 thrips to potted and caged timothy. Thrips abundance and foliar nutrients were measured 58 d after treatment placement. Plant quality directly affected thrips wing diphenism independent of thrips density in both experiments. Near the end of the field cage experiment, density may have indirectly impacted wing diphenism. In both experiments, plant quality and thrips density interacted to affect thrips population abundance. Plant quality alone can affect thrips wing diphenism, but it remains unclear whether density alone can affect thrips wing diphenism. This is a unique and understudied system that will be useful to examine generalized theories on the negative interaction between reproduction and dispersal.

Biological processes, quantum mechanics and electromagnetic fields: the possibility of device-encapsulated human intention in medical therapies.

PubMed

Kohane, M J; Tiller, W A

2001-06-01

The general hypothesis that quantum mechanics (QM) and thermodynamic concepts relate to biological systems is discussed and applied to the biological influence of: (1) electromagnetic fields (EMFs); and (2) EMFs that have been exposed to human intention. We illustrate our hypothesis with experiments involving four simultaneous treatments: exposure to ambient EMFs in the laboratory environment (C), exposure in a Faraday cage (F) and exposure in a Faraday cage with either: (i) an electronic device (IIED) which had been exposed to a specific human intention (d,j); or (ii) a non-exposed, physically identical, device (d,o). Experimental systems were fitness and energy metabolism in Drosophila melanogaster, in vitro enzyme activity and molecular concentration variability over time. Results indicated that shielding from ambient EMFs via a Faraday cage (F) made a significant difference relative to the unshielded control (C). Further, (d,o) had a significant lowering effect in the shielded environment. Finally, there was a strong 'intention' effect with the IIED (d,j) producing significant and positive effects in comparison to (d,o) in each experimental system. Copyright 2001 Harcourt Publishers Ltd.

Trapping, Deformation, and Rotation of Giant Unilamellar Vesicles in Octode Dielectrophoretic Field Cages

PubMed Central

Korlach, J.; Reichle, C.; Müller, T.; Schnelle, T.; Webb, W. W.

2005-01-01

The behavior of freestanding lipid bilayer membranes under the influence of dielectric force potentials was studied by trapping, holding, and rotating individual giant unilamellar vesicles (GUVs) inside dielectrophoretic microfield cages. Using laser scanning confocal microscopy and three-dimensional image reconstructions of GUVs labeled with fluorescent membrane probes, field strength and frequency-dependent vesicle deformations were observed which are explained by calculations of the dielectric force potentials inside the cage. Dynamical membrane properties under the influence of the field cage were studied by fluorescence correlation spectroscopy, circumventing potential artifacts associated with measurements involving GUV immobilization on support surfaces. Lipid transport could be accelerated markedly by the applied fields, aided by hydrodynamic fluid streaming which was also studied by fluorescence correlation spectroscopy. PMID:15863477

Laser photolysis of caged compounds at 405 nm: photochemical advantages, localisation, phototoxicity and methods for calibration.

PubMed

Trigo, Federico F; Corrie, John E T; Ogden, David

2009-05-30

Rapid, localised photolytic release of neurotransmitters from caged precursors at synaptic regions in the extracellular space is greatly hampered at irradiation wavelengths in the near-UV, close to the wavelength of maximum absorption of the caged precursor, because of inner-filtering by strong absorption of light in the cage solution between the objective and cell. For this reason two-photon excitation is commonly used for photolysis, particularly at multiple points distributed over large fields; or, with near-UV, if combined with local perfusion of the cage. These methods each have problems: the small cross-sections of common cages with two-photon excitation require high cage concentrations and light intensities near the phototoxic limit, while local perfusion gives non-uniform cage concentrations over the field of view. Single-photon photolysis at 405 nm, although less efficient than at 330-350 nm, with present cages is more efficient than two-photon photolysis. The reduced light absorption in the bulk cage solution permits efficient wide-field uncaging at non-toxic intensities with uniform cage concentration. Full photolysis of MNI-glutamate with 100 micros pulses required intensities of 2 mW microm(-2) at the preparation, shown to be non-toxic with repeated exposures. Light scattering at 405 nm was estimated as 50% at 18 microm depth in 21-day rat cerebellum. Methods are described for: (1) varying the laser spot size; (2) photolysis calibration in the microscope with the caged fluorophore NPE-HPTS over the wavelength range 347-405 nm; and (3) determining the point-spread function of excitation. Furthermore, DM-Nitrophen photolysis at 405 nm was efficient for intracellular investigations of Ca2+-dependent processes.

Comparative study of proliferative kidney disease in grayling Thymallus thymallus and brown trout Salmo trutta fario: an exposure experiment.

PubMed

Schmidt-Posthaus, Heike; Ros, Albert; Hirschi, Regula; Schneider, Ernst

2017-03-21

Proliferative kidney disease (PKD) is an emerging disease threatening wild salmonid populations, with the myxozoan parasite Tetracapsuloides bryosalmonae as the causative agent. Species differences in parasite susceptibility and disease-induced mortality seem to exist. The aim of the present study was to compare incidence, pathology and mortality of PKD in grayling Thymallus thymallus and brown trout Salmo trutta under identical semi-natural conditions. Young-of-the-year grayling and brown trout, free of T. bryosalmonae, were jointly exposed in cage compartments in a river in the northeast of Switzerland during 3 summer months. Wild brown trout were caught by electrofishing near the cage, and PKD status was compared with that of caged animals. Cage-exposed grayling showed a PKD incidence of 1%, regardless of whether parasite infection was determined by means of real-time PCR or histopathology/immunohistochemistry. In contrast, PKD incidence of caged brown trout was 77%. This value was not significantly different to PKD prevalence of wild brown trout caught above and below the cage (60 and 91%, respectively). Mortality in grayling was significantly higher compared with that of brown trout (40 versus 23%); however, grayling mortality was not considered to be associated with PKD. Mortality of caged and infected brown trout was significantly higher than mortality of non-infected caged trout. Histopathology indicated an ongoing mostly acute or chronic active infection in brown trout, which survived until the end of exposure. The results suggest that grayling are less susceptible to infection with T. bryosalmonae compared with brown trout under the tested field conditions.

In situ experiments to assess effects of constraints linked to caging on ecotoxicity biomarkers of the three-spined stickleback (Gasterosteus aculeatus L.).

PubMed

Le Guernic, Antoine; Sanchez, Wilfried; Palluel, Olivier; Bado-Nilles, Anne; Turies, Cyril; Chadili, Edith; Cavalié, Isabelle; Adam-Guillermin, Christelle; Porcher, Jean-Marc; Geffard, Alain; Betoulle, Stéphane; Gagnaire, Béatrice

2016-04-01

The aim of this study was to evaluate the effects of caging constraints on multiple fish biomarkers used during ecotoxicological studies (biometric data, immune and antioxidant systems, and energetic status). Two of these constraints were linked to caging: starvation and fish density in cages, and one in relation to the post-caging handling: a short transport. Three in situ experiments were conducted with three-spined sticklebacks (Gasterosteus aculeatus). The first experiment compared the effects of three densities (low, medium, and high). The second experiment compared effects of starvation in fish fed every two days with fish that were not fed. Finally comparisons between sticklebacks which have suffered a short car transport after caging and sticklebacks killed without preliminary transport were made. The lack of food had no effect on fish energetic reserves but negatively affected their condition index and their immune system. Transport and high density induced oxidative stress, defined as an overproduction of reactive oxygen species and a stimulation of the antioxidant system. These two constraints also harmed the leucocyte viability. In order not to have any impact on ecotoxicity biomarkers during in situ experiments, it is preferable to decrease fish density in cages, prevent transport before dissections, and feed fish when the caging lasts more than two weeks.

Caging and Photoactivation in Single-Molecule Förster Resonance Energy Transfer Experiments

PubMed Central

2017-01-01

Caged organic fluorophores are established tools for localization-based super-resolution imaging. Their use relies on reversible deactivation of standard organic fluorophores by chemical reduction or commercially available caged dyes with ON switching of the fluorescent signal by ultraviolet (UV) light. Here, we establish caging of cyanine fluorophores and caged rhodamine dyes, i.e., chemical deactivation of fluorescence, for single-molecule Förster resonance energy transfer (smFRET) experiments with freely diffusing molecules. They allow temporal separation and sorting of multiple intramolecular donor–acceptor pairs during solution-based smFRET. We use this “caged FRET” methodology for the study of complex biochemical species such as multisubunit proteins or nucleic acids containing more than two fluorescent labels. Proof-of-principle experiments and a characterization of the uncaging process in the confocal volume are presented. These reveal that chemical caging and UV reactivation allow temporal uncoupling of convoluted fluorescence signals from, e.g., multiple spectrally similar donor or acceptor molecules on nucleic acids. We also use caging without UV reactivation to remove unwanted overlabeled species in experiments with the homotrimeric membrane transporter BetP. We finally outline further possible applications of the caged FRET methodology, such as the study of weak biochemical interactions, which are otherwise impossible with diffusion-based smFRET techniques because of the required low concentrations of fluorescently labeled biomolecules. PMID:28362086

Impact of invasive aquatic macrophytes on the population and behavioral ecology of mosquitoes (Diptera: Culicidae)

USDA-ARS?s Scientific Manuscript database

A field survey, three outdoor cage enclosure experiments, and laboratory studies were conducted to elucidate the impact of the invasive aquatic weeds Eichhornia crassipes (floating water hyacinth), Ludwigia hexapetala (emergent water yellow-primrose), and Egeria densa (submersed Brazilian waterweed)...

Small Cages with Insect Couples Provide a Simple Method for a Preliminary Assessment of Mating Disruption

PubMed Central

Briand, Françoise; Guerin, Patrick M.; Charmillot, Pierre-Joseph; Kehrli, Patrik

2012-01-01

Mating disruption by sex pheromones is a sustainable, effective and widely used pest management scheme. A drawback of this technique is its challenging assessment of effectiveness in the field (e.g., spatial scale, pest density). The aim of this work was to facilitate the evaluation of field-deployed pheromone dispensers. We tested the suitability of small insect field cages for a pre-evaluation of the impact of sex pheromones on mating using the grape moths Eupoecilia ambiguella and Lobesia botrana, two major pests in vineyards. Cages consisted of a cubic metal frame of 35 cm sides, which was covered with a mosquito net of 1500 μm mesh size. Cages were installed in the centre of pheromone-treated and untreated vineyards. In several trials, 1 to 20 couples of grape moths per cage were released for one to three nights. The proportion of mated females was between 15 to 70% lower in pheromone-treated compared to untreated vineyards. Overall, the exposure of eight couples for one night was adequate for comparing different control schemes. Small cages may therefore provide a fast and cheap method to compare the effectiveness of pheromone dispensers under standardised semi-field conditions and may help predict the value of setting-up large-scale field trials. PMID:22645483

Magnetic bucket for rotating unmagnetized plasma.

PubMed

Katz, Noam; Collins, Cami; Wallace, John; Clark, Mike; Weisberg, David; Jara-Almonte, Jon; Reese, Ingrid; Wahl, Carl; Forest, Cary

2012-06-01

A new experiment is described which generates flow in unmagnetized plasma. Confinement is provided by a cage of permanent magnets, arranged to form an axisymmetric, high-order, multipolar magnetic field. This field configuration-sometimes called a "magnetic bucket"-has a vanishingly small field in the core of the experiment. Toroidal rotation is driven by J × B forces applied in the magnetized edge. The cross-field current that is required for this forcing flows from anodes to thermionic cathodes, which are inserted between the magnet rings. The rotation at the edge reaches 3 km/s and is viscously coupled to the unmagnetized core plasma. We describe the conditions necessary for rotation, as well as a 0-dimensional power balance used to understand plasma confinement in the experiment.

Designing an Active Target Test Projection Chamber

NASA Astrophysics Data System (ADS)

Koci, James; Tan Ahn Collaboration, Dr.; Nicolas Dixneuf Collaboration

2015-10-01

The development of instrumentation in nuclear physics is crucial for advancing our ability to measure the properties of exotic nuclei. One limitation of the use of exotic nuclei in experiment is their very low production intensities. Recently, detectors, called active-target dectectors, have been developed to address this issue. Active-target detectors use a gas medium to image charged-particle tracks that are emitted in nuclear reactions. Last semester, I designed a vacuum chamber to be used in developing Micro-Pattern Gas detectors that will upgrade the capabilities of an active-target detector called the Prototype AT-TPC. With the exterior of the chamber complete, I have now been using an electric field modeling program, Garfield, developed by CERN to design a field cage to be placed within the vacuum chamber. The field cage will be a box-like apparatus consisting of two parallel metal plates connected with a resistor chain and attached to wires wrapped between them. The cage will provide a uniform electric field within the chamber to drift electrons from nuclear reactions down to the detector in the bottom of the chamber. These signals are then amplified by a proportional counter, and the data is sent to a computer. For the long term, we would like to incorporate a Micro-Pattern Gas Detectors in the interior of the chamber and eventually use the AT-TPC to examine various nuclei. Dr. Ahn is my advising professor.

Red mason bees cannot compete with honey bees for floral resources in a cage experiment.

PubMed

Hudewenz, Anika; Klein, Alexandra-Maria

2015-11-01

Intensive beekeeping to mitigate crop pollination deficits and habitat loss may cause interspecific competition between bees. Studies show negative correlations between flower visitation of honey bees (Apis mellifera) and wild bees, but effects on the reproduction of wild bees were not proven. Likely reasons are that honey bees can hardly be excluded from controls and wild bee nests are generally difficult to detect in field experiments. The goal of this study was to investigate whether red mason bees (Osmia bicornis) compete with honey bees in cages in order to compare the reproduction of red mason bees under different honey bee densities. Three treatments were applied, each replicated in four cages of 18 m³ with 38 red mason bees in all treatments and 0, 100, and 300 honey bees per treatment with 10-20% being foragers. Within the cages, the flower visitation and interspecific displacements from flowers were observed. Niche breadths and resource overlaps of both bee species were calculated, and the reproduction of red mason bees was measured. Red mason bees visited fewer flowers when honey bees were present. Niche breadth of red mason bees decreased with increasing honey bee density while resource overlaps remained constant. The reproduction of red mason bees decreased in cages with honey bees. In conclusion, our experimental results show that in small and isolated flower patches, wild bees can temporarily suffer from competition with honey bees. Further research should aim to test for competition on small and isolated flower patches in real landscapes.

Homogenized boundary conditions and resonance effects in Faraday cages

PubMed Central

Hewitt, I. J.

2016-01-01

We present a mathematical study of two-dimensional electrostatic and electromagnetic shielding by a cage of conducting wires (the so-called ‘Faraday cage effect’). Taking the limit as the number of wires in the cage tends to infinity, we use the asymptotic method of multiple scales to derive continuum models for the shielding, involving homogenized boundary conditions on an effective cage boundary. We show how the resulting models depend on key cage parameters such as the size and shape of the wires, and, in the electromagnetic case, on the frequency and polarization of the incident field. In the electromagnetic case, there are resonance effects, whereby at frequencies close to the natural frequencies of the equivalent solid shell, the presence of the cage actually amplifies the incident field, rather than shielding it. By appropriately modifying the continuum model, we calculate the modified resonant frequencies, and their associated peak amplitudes. We discuss applications to radiation containment in microwave ovens and acoustic scattering by perforated shells. PMID:27279775

Homogenized boundary conditions and resonance effects in Faraday cages

NASA Astrophysics Data System (ADS)

Hewett, D. P.; Hewitt, I. J.

2016-05-01

We present a mathematical study of two-dimensional electrostatic and electromagnetic shielding by a cage of conducting wires (the so-called `Faraday cage effect'). Taking the limit as the number of wires in the cage tends to infinity, we use the asymptotic method of multiple scales to derive continuum models for the shielding, involving homogenized boundary conditions on an effective cage boundary. We show how the resulting models depend on key cage parameters such as the size and shape of the wires, and, in the electromagnetic case, on the frequency and polarization of the incident field. In the electromagnetic case, there are resonance effects, whereby at frequencies close to the natural frequencies of the equivalent solid shell, the presence of the cage actually amplifies the incident field, rather than shielding it. By appropriately modifying the continuum model, we calculate the modified resonant frequencies, and their associated peak amplitudes. We discuss applications to radiation containment in microwave ovens and acoustic scattering by perforated shells.

Homogenized boundary conditions and resonance effects in Faraday cages.

PubMed

Hewett, D P; Hewitt, I J

2016-05-01

We present a mathematical study of two-dimensional electrostatic and electromagnetic shielding by a cage of conducting wires (the so-called 'Faraday cage effect'). Taking the limit as the number of wires in the cage tends to infinity, we use the asymptotic method of multiple scales to derive continuum models for the shielding, involving homogenized boundary conditions on an effective cage boundary. We show how the resulting models depend on key cage parameters such as the size and shape of the wires, and, in the electromagnetic case, on the frequency and polarization of the incident field. In the electromagnetic case, there are resonance effects, whereby at frequencies close to the natural frequencies of the equivalent solid shell, the presence of the cage actually amplifies the incident field, rather than shielding it. By appropriately modifying the continuum model, we calculate the modified resonant frequencies, and their associated peak amplitudes. We discuss applications to radiation containment in microwave ovens and acoustic scattering by perforated shells.

Laboratory bioassays and field-cage trials of Metarhizium spp. isolates with field-collected Mormon crickets (Anabrus simplex)

USDA-ARS?s Scientific Manuscript database

The Mormon cricket, Anabrus simplex, is an important pest in the western United States. This study evaluates the virulence of 32 isolates of Metarhizium towards field-collected Mormon crickets. Additionally, several isolates were tested in outdoor field-cage studies. All 32 Metarhizium isolates were...

[Experiences with cage combinations for guinea pigs].

PubMed

von Zychlinski, J

1989-01-01

Special cage units described in 1982 for guinea pigs have been used either as cages for small groups of breeding animals or for caging of growing animals. By using these cages the following advantages have been noted; the cage size can be adapted to number, age and body weight of the animals; aggression and panic are avoided by corners, walls and tunnels; economic use of breeding males by mating with more females.

Wetland management and rice farming strategies to decrease methylmercury bioaccumulation and loads from the Cosumnes River Preserve, California

USGS Publications Warehouse

Eagles-Smith, Collin A.; Ackerman, Joshua T.; Fleck, Jacob; Windham-Myers, Lisamarie; McQuillen, Harry; Heim, Wes

2014-01-01

We evaluated mercury (Hg) concentrations in caged fish (deployed for 30 days) and water from agricultural wetland (rice fields), managed wetland, slough, and river habitats in the Cosumnes River Preserve, California. We also implemented experimental hydrological regimes on managed wetlands and post-harvest rice straw management techniques on rice fields in order to evaluate potential Best Management Practices to decrease methylmercury bioaccumulation within wetlands and loads to the Sacramento-San Joaquin River Delta. Total Hg concentrations in caged fish were twice as high in rice fields as in managed wetland, slough, or riverine habitats, including seasonal managed wetlands subjected to identical hydrological regimes. Caged fish Hg concentrations also differed among managed wetland treatments and post-harvest rice straw treatments. Specifically, Hg concentrations in caged fish decreased from inlets to outlets in seasonal managed wetlands with either a single (fall-only) or dual (fall and spring) drawdown and flood-up events, whereas Hg concentrations increased slightly from inlets to outlets in permanent managed wetlands. In rice fields, experimental post-harvest straw management did not decrease Hg concentrations in caged fish. In fact, in fields in which rice straw was chopped and either disked into the soil or baled and removed from the fields, fish Hg concentrations increased from inlets to outlets and were higher than Hg concentrations in fish from rice fields subjected to the more standard post-harvest practice of simply chopping rice straw prior to fall flood-up. Finally, aqueous methylmercury (MeHg) concentrations and export were highly variable, and seasonal trends in particular were often opposite to those of caged fish. Aqueous MeHg concentrations and loads were substantially higher in winter than in summer, whereas caged fish Hg concentrations were relatively low in winter and substantially higher in summer. Together, our results highlight the importance of habitat, seasonal processes, and wetland management practices on Hg cycling and ecological risk in aquatic ecosystems.

Polarization response of clathrate hydrates capsulated with guest molecules

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

Zeng, Qun; Li, Jinshan, E-mail: ljs915@263.net, E-mail: myang@scu.edu.cn; Huang, Hui

2016-05-28

Clathrate hydrates are characterized by their water cages encapsulating various guest atoms or molecules. The polarization effect of these guest-cage complexes was studied with combined density functional theory and finite-field calculations. An addition rule was noted for these systems whose total polarizability is approximately equal to the polarizability sum of the guest and the cage. However, their distributional polarizability computed with Hirshfeld partitioning scheme indicates that the guest–cage interaction has considerable influence on their polarization response. The polarization of encapsulated guest is reduced while the polarization of water cage is enhanced. The counteraction of these two opposite effects leads tomore » the almost unchanged total polarizability. Further analysis reveals that the reduced polarizability of encapsulated guest results from the shielding effect of water cage against the external field and the enhanced polarizability of water cage from the enhanced bonding of hydrogen bonds among water molecules. Although the charge transfer through the hydrogen bonds is rather small in the water cage, the polarization response of clathrate hydrates is sensitive to the changes of hydrogen bonding strength. The guest encapsulation strengthens the hydrogen bonding network and leads to enhanced polarizability.« less

Trp-cage: folding free energy landscape in explicit water.

PubMed

Zhou, Ruhong

2003-11-11

Trp-cage is a 20-residue miniprotein, which is believed to be the fastest folder known so far. In this study, the folding free energy landscape of Trp-cage has been explored in explicit solvent by using an OPLSAA force field with periodic boundary condition. A highly parallel replica exchange molecular dynamics method is used for the conformation space sampling, with the help of a recently developed efficient molecular dynamics algorithm P3ME/RESPA (particle-particle particle-mesh Ewald/reference system propagator algorithm). A two-step folding mechanism is proposed that involves an intermediate state where two correctly formed partial hydrophobic cores are separated by an essential salt-bridge between residues Asp-9 and Arg-16 near the center of the peptide. This metastable intermediate state provides an explanation for the superfast folding process. The free energy landscape is found to be rugged at low temperatures, and then becomes smooth and funnel-like above 340 K. The lowest free energy structure at 300 K is only 1.50 A Calpha-RMSD (Calpha-rms deviation) from the NMR structures. The simulated nuclear Overhauser effect pair distances are in excellent agreement with the raw NMR data. The temperature dependence of the Trp-cage population, however, is found to be significantly different from experiment, with a much higher melting transition temperature above 400 K (experimental 315 K), indicating that the current force fields, parameterized at room temperature, need to be improved to correctly predict the temperature dependence.

Trp-cage: Folding free energy landscape in explicit water

NASA Astrophysics Data System (ADS)

Zhou, Ruhong

2003-11-01

Trp-cage is a 20-residue miniprotein, which is believed to be the fastest folder known so far. In this study, the folding free energy landscape of Trp-cage has been explored in explicit solvent by using an OPLSAA force field with periodic boundary condition. A highly parallel replica exchange molecular dynamics method is used for the conformation space sampling, with the help of a recently developed efficient molecular dynamics algorithm P3ME/RESPA (particle-particle particle-mesh Ewald/reference system propagator algorithm). A two-step folding mechanism is proposed that involves an intermediate state where two correctly formed partial hydrophobic cores are separated by an essential salt-bridge between residues Asp-9 and Arg-16 near the center of the peptide. This metastable intermediate state provides an explanation for the superfast folding process. The free energy landscape is found to be rugged at low temperatures, and then becomes smooth and funnel-like above 340 K. The lowest free energy structure at 300 K is only 1.50 Å C-RMSD (C-rms deviation) from the NMR structures. The simulated nuclear Overhauser effect pair distances are in excellent agreement with the raw NMR data. The temperature dependence of the Trp-cage population, however, is found to be significantly different from experiment, with a much higher melting transition temperature above 400 K (experimental 315 K), indicating that the current force fields, parameterized at room temperature, need to be improved to correctly predict the temperature dependence.

Trp-cage: Folding free energy landscape in explicit water

PubMed Central

Zhou, Ruhong

2003-01-01

Trp-cage is a 20-residue miniprotein, which is believed to be the fastest folder known so far. In this study, the folding free energy landscape of Trp-cage has been explored in explicit solvent by using an OPLSAA force field with periodic boundary condition. A highly parallel replica exchange molecular dynamics method is used for the conformation space sampling, with the help of a recently developed efficient molecular dynamics algorithm P3ME/RESPA (particle–particle particle–mesh Ewald/reference system propagator algorithm). A two-step folding mechanism is proposed that involves an intermediate state where two correctly formed partial hydrophobic cores are separated by an essential salt-bridge between residues Asp-9 and Arg-16 near the center of the peptide. This metastable intermediate state provides an explanation for the superfast folding process. The free energy landscape is found to be rugged at low temperatures, and then becomes smooth and funnel-like above 340 K. The lowest free energy structure at 300 K is only 1.50 Å Cα-RMSD (Cα-rms deviation) from the NMR structures. The simulated nuclear Overhauser effect pair distances are in excellent agreement with the raw NMR data. The temperature dependence of the Trp-cage population, however, is found to be significantly different from experiment, with a much higher melting transition temperature above 400 K (experimental 315 K), indicating that the current force fields, parameterized at room temperature, need to be improved to correctly predict the temperature dependence. PMID:14581616

[The development of methylcholanthrene-tumors in mice under the environmental influence of various electrobioclimatological conditions (author's transl)].

PubMed

Möse, J R; Fischer, G

1977-08-01

Comparative analyses of the development rate of a slow Tumor (Methylcholanthrene) in mice were undertaken under conditions of a) an electrostatic field (Field strength 200 V/m, Residual sinus component 0.1%), b) a Faraday cage (Shielding effectivity on atmospheric electrical disturbances: 99%) and c) a laboratory, climatized with conventional methods. The tumor was initiated in each case following a 6-week acclimatisation period to the unaccustomed surroundings. Following this, we observed the appearance rates over a period of 8 months at 14-day intervals. Under customary laboratory conditions these were perceptibly higher than in the electrostatic field or in the Faraday cage. No difference was apparent between the two latter conditions. Any variations in the electrobioclimatological environment can lead to stress reactions resulting in familiar consequences to various defense mechanisms. This allows us to find an explanation for the results otherwise difficult to interpret; for both in the electrostatic field and under shielding from external electrical influences the neoplastic activity was obviously reduced in comparison to normally climatized laboratory conditions. We are continuing the experiments.

Use of fly ash in diets of cage and floor broilers

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

Pharr, C.L.; Andrews, L.D.

1980-09-01

Three experiments were conducted to compare limestone to fly ash from a coal-fired generator station as a calcium source for broilers. In experiment 1, 5 male and 5 female broiler chicks were placed in each of 32 cages. Sixteen cages of birds were fed a ration with limestone supplying 30% of the total calcium and 16 cages were fed a ration with 30% of the total calcium supplied by fly ash. The total calcium and phosphorus levels of the rations were 1.0% and .5%, respectively. In this experiment no significant difference was found for 8-week body weight between diets wheremore » the added calcium was from limestone or fly ash. In experiment 2 a group of 40 male and 40 female cage reared broilers and 40 male and 40 female floor reared broilers were fed a basal diet of limestone providing 33% of the total calcium. Three diets with increasing fly ash levels were fed to three cage groups of 40 male and 40 female broilers providing 33, 46, and 45% of the total calcium of .9, 1.1, and 1.8%, respectively. Broilers fed the highest fly ash level weighed significantly less at 8 weeks than the caged controls but did not differ from the other treatments. Bone breaking strength as measured by the Allo Kramer Shear Press was similar between the basal and low level fly ash group and increased with higher fly ash levels. In experiment 3 four groups of 40 male broilers in cages were fed limestone diets with graded levels of limestone for the calcium source. Another four groups of 40 caged male broilers were fed fly ash diets with equivalent graded levels of fly ash for the calcium source. Both limestone and fly ash diets provided .17, .34, .51, and .68% calcium of a total calcium content of .28, .45, .62, and .79%, respectively.« less

Multipole induced splitting of metal-cage vibrations in crystalline endohedral D2d-M2@C84 dimetallofullerenes.

PubMed

Krause, M; Popov, V N; Inakuma, M; Tagmatarchis, N; Shinohara, H; Georgi, P; Dunsch, L; Kuzmany, H

2004-01-22

Metal-carbon cage vibrations of crystalline endohedral D2d-M2@C84 (M=Sc,Y,Dy) dimetallofullerenes were analyzed by temperature dependent Raman scattering and a dynamical force field model. Three groups of metal-carbon cage modes were found at energies of 35-200 cm(-1) and assigned to metal-cage stretching and deformation vibrations. They exhibit a textbook example for the splitting of molecular vibrations in a crystal field. Induced dipole-dipole and quadrupole-quadrupole interactions account quantitatively for the observed mode splitting. Based on the metal-cage vibrational structure it is demonstrated that D2d-Y2@C84 dimetallofullerene retains a monoclinic crystal structure up to 550 K and undergoes a transition from a disordered to an ordered orientational state at a temperature of approximately 150 K.

Effects of radio frequency magnetic fields on iron release from cage proteins.

PubMed

Céspedes, Oscar; Ueno, Shoogo

2009-07-01

Ferritin, the iron cage protein, contains a superparamagnetic ferrihydrite nanoparticle formed from the oxidation and absorption of Fe(2+) ions. This nanoparticle increases its internal energy when exposed to alternating magnetic fields due to magnetization lag. The energy is then dissipated to the surrounding proteic cage, affecting its functioning. In this article we show that the rates of iron chelation with ferrozine, an optical marker, are reduced by up to a factor of 3 in proteins previously exposed to radio frequency magnetic fields of 1 MHz and 30 microT for several hours. The effect is non-thermal and depends on the frequency-amplitude product of the magnetic field. (c) 2009 Wiley-Liss, Inc.

Scramble competition in the southern pine beetle, Dendroctonus frontalis

Treesearch

John D. Reeve; Douglas J. Rhodes; Peter Turchin

1998-01-01

1. The nature of intraspecific competition was investigated in the southern pine beetle, Dendroctonus frontalis, a highly destructive pest of pine forests in the southern U.S.A.Date were analyzed from an observation study of naturally-attacked trees, and from field experiments where attack density was manipulated by adding different numbers of beetles to caged trees....

Enhanced sampling molecular dynamics simulation captures experimentally suggested intermediate and unfolded states in the folding pathway of Trp-cage miniprotein.

PubMed

Shao, Qiang; Shi, Jiye; Zhu, Weiliang

2012-09-28

The ability of molecular dynamics simulation to capturing the transient states within the folding pathway of protein is important to the understanding of protein folding mechanism. In the present study, the integrated-tempering-sampling molecular dynamics (ITS-MD) simulation was performed to investigate the transient states including intermediate and unfolded ones in the folding pathway of a miniprotein, Trp-cage. Three force fields (FF03, FF99SB, and FF96) were tested, and both intermediate and unfolded states with their characteristics in good agreement with experiments were observed during the simulations, which supports the hypothesis that observable intermediates might present in the folding pathway of small polypeptides. In addition, it was demonstrated that FF03 force field as combined with ITS-MD is in overall a more proper force field than the others in reproducing experimentally recorded properties in UVRS, ECD, and NMR, Photo-CIDNP NMR, and IR T-jump experiments, and the folding∕unfolding thermodynamics parameters, such as ΔG(U), ΔC(p), and ΔH(U) (T(m)). In summary, the present study showed that using suitable force field and energy sampling method, molecular dynamics simulation could capture the transient states within the folding pathway of protein which are consistent with the experimental measurements, and thus provide information of protein folding mechanism and thermodynamics.

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

PubMed

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

2009-07-01

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

Proton Radiography of Spontaneous Fields, Plasma Flows and Dynamics in X-Ray Driven Inertial-Confinement Fusion Implosions

NASA Astrophysics Data System (ADS)

Li, C. K.; Seguin, F. H.; Frenje, J. A.; Rosenberg, M.; Zylstra, A. B.; Rinderknecht, H. G.; Petrasso, R. D.; Amendt, P. A.; Landen, O. L.; Town, R. P. J.; Betti, R.; Knauer, J. P.; Meyerhofer, D. D.; Back, C. A.; Kilkenny, J. D.; Nikroo, A.

2010-11-01

Backlighting of x-ray-driven implosions in empty hohlraums with mono-energetic protons on the OMEGA laser facility has allowed a number of important phenomena to be observed. Several critical parameters were determined, including plasma flow, three types of spontaneous electric fields and megaGauss magnetic fields. These results provide insight into important issues in indirect-drive ICF. Even though the cavity is effectively a Faraday cage, the strong, local fields inside the hohlraum can affect laser-plasma instabilities, electron distributions and implosion symmetry. They are of fundamental scientific importance for a range of new experiments at the frontiers of high-energy-density physics. Future experiments designed to characterize the field formation and evolution in low-Z gas fill hohlraums will be discussed.

Spatial cognition in a virtual reality home-cage extension for freely moving rodents

PubMed Central

Kaupert, Ursula; Frei, Katja; Bagorda, Francesco; Schatz, Alexej; Tocker, Gilad; Rapoport, Sophie; Derdikman, Dori

2017-01-01

Virtual reality (VR) environments are a powerful tool to investigate brain mechanisms involved in the behavior of animals. With this technique, animals are usually head fixed or secured in a harness, and training for cognitively more complex VR paradigms is time consuming. A VR apparatus allowing free animal movement and the constant operator-independent training of tasks would enable many new applications. Key prospective usages include brain imaging of animal behavior when carrying a miniaturized mobile device such as a fluorescence microscope or an optetrode. Here, we introduce the Servoball, a spherical VR treadmill based on the closed-loop tracking of a freely moving animal and feedback counterrotation of the ball. Furthermore, we present the complete integration of this experimental system with the animals’ group home cage, from which single individuals can voluntarily enter through a tunnel with radio-frequency identification (RFID)-automated access control and commence experiments. This automated animal sorter functions as a mechanical replacement of the experimenter. We automatically trained rats using visual or acoustic cues to solve spatial cognitive tasks and recorded spatially modulated entorhinal cells. When electrophysiological extracellular recordings from awake behaving rats were performed, head fixation can dramatically alter results, so that any complex behavior that requires head movement is impossible to achieve. We circumvented this problem with the use of the Servoball in open-field scenarios, as it allows the combination of open-field behavior with the recording of nerve cells, along with all the flexibility that a virtual environment brings. This integrated home cage with a VR arena experimental system permits highly efficient experimentation for complex cognitive experiments. NEW & NOTEWORTHY Virtual reality (VR) environments are a powerful tool for the investigation of brain mechanisms. We introduce the Servoball, a VR treadmill for freely moving rodents. The Servoball is integrated with the animals’ group home cage. Single individuals voluntarily enter using automated access control. Training is highly time-efficient, even for cognitively complex VR paradigms. PMID:28077665

Fruit Set and Single Visit Stigma Pollen Deposition by Managed Bumble Bees and Wild Bees in Citrullus lanatus (Cucurbitales: Cucurbitaceae).

PubMed

Campbell, Joshua W; Daniels, Jaret C; Ellis, James D

2018-04-02

Pollinators provide essential services for watermelon, Citrullus lanatus (Thunb.; Cucurbitales: Cucurbitaceae). Managed bumble bees, Bombus impatiens (Cresson; Hymenoptera: Apidae), have been shown to be a useful watermelon pollinator in some areas. However, the exact contribution bumble bees make to watermelon pollination and how their contribution compares to that of other bees is unclear. We used large cages (5.4 × 2.5 × 2.4 m) to confine bumble bee hives to watermelon plants and compared fruit set in those cages to cages containing watermelons but no pollinators, and to open areas of field next to cages (allows all pollinators). We also collected data on single visit pollen deposition onto watermelon stigmas by managed bumble bees, honey bees, and wild bees. Overall, more fruit formed within the open cages than in cages of the other two treatment groups. B. impatiens and Melissodes spp. deposited the most pollen onto watermelon stigmas per visit, but all bee species observed visiting watermelon flowers were capable of depositing ample pollen to watermelon stigmas. Although B. impatiens did deposit large quantities of pollen to stigmas, they were not common within the field (i.e., outside the cages) as they were readily drawn to flowering plants outside of the watermelon field. Overall, bumble bees can successfully pollinate watermelon, but may be useful in greenhouses or high tunnels where watermelon flowers have no competition from other flowering plants that could draw bumble bees away from watermelon.

Intracage ammonia levels in static and individually ventilated cages housing C57BL/6 mice on 4 bedding substrates.

PubMed

Ferrecchia, Christie E; Jensen, Kelly; Van Andel, Roger

2014-03-01

The relationship among ammonia levels, cage-changing frequency, and bedding types is an important and potentially controversial topic in the laboratory animal science community. Some bedding options may not provide sufficient urine absorption and bacterial regulation to minimize ammonia production during the interval between cage changes. High intracage ammonia levels can cause subclinical degeneration and inflammation of nasal passages, rhinitis and olfactory epithelial necrosis in exposed mice. Here we sought to compare the effects of 4 commonly used bedding substrates (1/4-in. irradiated corncob, reclaimed wood pulp, aspen wood chips, and recycled newspaper) on ammonia generation when housing female C57BL/6 mice in static and individually ventilated caging. Intracage ammonia levels were measured daily for 1 wk (static cage experiment) or 2 wk (IVC experiment). The results of this study suggest that the corncob, aspen wood chip, and recycled newspaper beddings that we tested are suitable for once-weekly cage changing for static cages and for changing every 2 wk for IVC. However, ammonia levels were not controlled appropriately in cages containing reclaimed wood pulp bedding, and pathologic changes occurred within 1 wk in the nares of mice housed on this bedding in static cages.

Intracage Ammonia Levels in Static and Individually Ventilated Cages Housing C57BL/6 Mice on 4 Bedding Substrates

PubMed Central

Ferrecchia, Christie E; Jensen, Kelly; Andel, Roger Van

2014-01-01

The relationship among ammonia levels, cage-changing frequency, and bedding types is an important and potentially controversial topic in the laboratory animal science community. Some bedding options may not provide sufficient urine absorption and bacterial regulation to minimize ammonia production during the interval between cage changes. High intracage ammonia levels can cause subclinical degeneration and inflammation of nasal passages, rhinitis and olfactory epithelial necrosis in exposed mice. Here we sought to compare the effects of 4 commonly used bedding substrates (1/4-in. irradiated corncob, reclaimed wood pulp, aspen wood chips, and recycled newspaper) on ammonia generation when housing female C57BL/6 mice in static and individually ventilated caging. Intracage ammonia levels were measured daily for 1 wk (static cage experiment) or 2 wk (IVC experiment). The results of this study suggest that the corncob, aspen wood chip, and recycled newspaper beddings that we tested are suitable for once-weekly cage changing for static cages and for changing every 2 wk for IVC. However, ammonia levels were not controlled appropriately in cages containing reclaimed wood pulp bedding, and pathologic changes occurred within 1 wk in the nares of mice housed on this bedding in static cages. PMID:24602540

Development of a home cage locomotor tracking system capable of detecting the stimulant and sedative properties of drugs in rats.

PubMed

Dunne, Fergal; O'Halloran, Ambrose; Kelly, John P

2007-10-01

The advent of automated locomotor activity methodologies has been extremely useful in removing the subjectivity and bias out of measuring this parameter in rodents. However, many of these behavioural studies are still conducted in novel environments, rather than in ones that the animals are familiar with, such as their home cage. The purpose of the present series of experiments was to develop an automated home cage tracking (HCT) profile using EthoVision software and assessing the acute effects of stimulant (amphetamine and methamphetamine, 0-5 mg/kg, sc) and sedative (diazepam, 0-20 mg/kg, sc and chlordiazepoxide, 0-50 mg/kg sc) drugs in this apparatus. Young adult male Sprague-Dawley rats were used, and the home cage locomotor activity was recorded for 11-60 min following administration (n=4 per group). For amphetamine and methamphetamine, a dose-dependent increase in home cage activity was evident for both drugs, with a plateau, followed by reduction at higher doses. Methamphetamine was more potent, whereas amphetamine produced greater maximal responses. Both diazepam and chlordiazepoxide dose-dependently reduced locomotor activity, with diazepam exhibiting a greater potency and having stronger sedative effects than chlordiazepoxide. Three doses of each drug were selected at the 31-40 min time period following administration, and compared to open field responses. Diazepam, chlordiazepoxide and amphetamine did not produce significant changes in the open field, whilst methamphetamine produced a significant increase in the 2.5 mg/kg group. In conclusion, these studies have successfully developed a sensitive HCT methodology that has been validated using drugs with stimulant and sedative properties in the same test conditions, with relatively small numbers of animals required to produce statistically significant results. It has proven superior to the open field investigations in allowing dose-response effects to be observed over a relatively short observation period (i.e. 10 min) for both stimulants and sedatives. In addition, the HCT system can determine differences in potency and efficacy between drugs of a similar chemical class.

F1 Sterile insect technique: a novel approach for risk assessment of Episimus unguiculus (Lepidoptera: Tortricidae), a candidate biological control agent of Schinus terebinthifolus in the Continental USA

USDA-ARS?s Scientific Manuscript database

Federal regulations mandate that researchers in the field of classical weed biological control follow the precautionary principle when proposing the release of an organism that can affect our environment. However, the host range observed in traditional laboratory cage experiments typically is broad...

Extreme ultraviolet patterning of tin-oxo cages

NASA Astrophysics Data System (ADS)

Haitjema, Jarich; Zhang, Yu; Vockenhuber, Michaela; Kazazis, Dimitrios; Ekinci, Yasin; Brouwer, Albert M.

2017-07-01

We report on the extreme ultraviolet (EUV) patterning performance of tin-oxo cages. These cage molecules were already known to function as a negative tone photoresist for EUV radiation, but in this work, we significantly optimized their performance. Our results show that sensitivity and resolution are only meaningful photoresist parameters if the process conditions are optimized. We focus on contrast curves of the materials using large area EUV exposures and patterning of the cages using EUV interference lithography. It is shown that baking steps, such as postexposure baking, can significantly affect both the sensitivity and contrast in the open-frame experiments as well as the patterning experiments. A layer thickness increase reduced the necessary dose to induce a solubility change but decreased the patterning quality. The patterning experiments were affected by minor changes in processing conditions such as an increased rinsing time. In addition, we show that the anions of the cage can influence the sensitivity and quality of the patterning, probably through their effect on physical properties of the materials.

Calling behavior of mass-reared and wild Anastrepha serpentina (Diptera: Tephritidae).

PubMed

Castrejón-Gómez, Victor R; Lascares, Shaila; Malo, Edi A; Toledo, Jorge; Rojas, Julio C

2007-08-01

The calling behavior of mass-reared and wild males of Anastrepha serpentina (Wiedemann) (Diptera: Tephritidae) was studied both in the laboratory and in field cage tests. In the laboratory, density (1, 5, and 10 males per container), age, and hour of day significantly affected calling behavior. Mass-reared males called independently of density, whereas wild males only called at densities of 5 and 10 individuals. Males of both strains started calling when they were 5-7 d old. The daily pattern of male calling was similar in both strains, starting at 0730 hours, and reaching a peak at 1330-1630 hours. Field cage tests showed that mass-reared males started calling when they were 5d old; the period of peak calling was when males were 8-9 d old. In contrast, wild males began calling when they were 10 d old, reaching peaks when males were 13, 15, and 18 d old. Wild males tended to form leks to call during each day of the experiment, whereas mass-reared males only formed leks during 2 d, both strains displaying very low levels. During field cage tests, males, independently of strain, displayed two calling peaks, one peak in the morning and one peak in the afternoon, whereas males observed in the laboratory only showed a single calling peak. The results are discussed in view of the effects of mass rearing A. serpentina males in relation to potential use of the sterile insect technique.

The effect of gamma radiation on sterility and mating ability of brown planthopper, Nilaparvata lugens(Stål) in field cage

NASA Astrophysics Data System (ADS)

Limohpasmanee, W.; Kongratarpon, T.; Tannarin, T.

2017-06-01

The brown planthopper, Nilaparvata lugens(Stål) is the major rice pest in Thailand. Adults and nymphs suck the sap from the rice plant causing it to wilt and transmitting the grassy stunt and the ragged stunt diseases. The population suppression by the sterile insect technique is overwhelmingly a function of mating between sterile males and wild females. The objectives of these experiments were to determine the suitable dose which induces partially sterile in N. lugens and their effect on wild population in the field cages. One-day-old 4th and 5th instar nymphs and adults were irradiated in a 60Co irradiator at the doses of 30, 60, 90 and 120 Gy. It was found that irradiation at the dose of 90 Gy induced complete sterility in female and 78.47 % sterility in males. The inherited sterility were transferred to their progenies and induced 51.46 and 77.00 % sterility in F-1 males and females. The irradiation as the mention dose did not affect mating ability. The competitiveness index was increased when the ratio of irradiated males per normal male was increased. The releasing irradiated males at 10 fold of normal males in field cages could suppress F-1 population 80.11 % and suppress F-2 population 80.32 % when compare with the control. This technique may be applied to delay and/or reduce seasonal increase of brown planthopper.

[Occupational exposure of physical therapists to electric and magnetic fields and the efficacy of Faraday cages].

PubMed

Messias, Iracimara de Anchieta; Okuno, Emico; Colacioppo, Sérgio

2011-10-01

Measure physical therapists' exposure to the electric and magnetic fields produced by 17 shortwave diathermy devices in physical therapy clinics in the city of Presidente Prudente, São Paulo State, Brazil. Compare the observed values with the exposure levels recommended by the International Commission on Non-ionizing Radiation Protection (ICNIRP). Observe the efficacy of Faraday cages as a means of protecting physical therapists from exposure to oscillating electric and magnetic fields. Electric and magnetic field measurements were taken at four points during actual physical therapy sessions: in proximity to the operator's pelvis and head, the devices' electrical cables, and the electrodes. The measuring equipment was a Wandel & Goltermann EMR-200. The values obtained in proximity to the electrodes and cables were 10 to 30 times higher than ICNIRP's recommended occupational reference levels. In the shortwave diathermy treatment rooms with Faraday cages, the fields were even higher than in treatment rooms not so equipped-principally the magnetic field, where the values were more than 100 times higher than the ICNIRP exposure limit. The electric and magnetic field intensities obtained in this study are generally above the exposure levels recommend in ICNIRP standards. It was also observed that the Faraday cage offers physical therapists no protection, and instead, increases their level of exposure.

Depopulation of Caged Layer Hens with a Compressed Air Foam System

PubMed Central

Gurung, Shailesh; Hoffman, John; Stringfellow, Kendre; Abi-Ghanem, Daad; Zhao, Dan; Caldwell, David; Lee, Jason; Styles, Darrel; Berghman, Luc; Byrd, James; Farnell, Yuhua; Archer, Gregory

2018-01-01

Simple Summary Reportable diseases, such as avian influenza, spread rapidly among poultry, resulting in the death of a large number of birds. Once such a disease has been diagnosed at a farm, infected and susceptible birds are rapidly killed to prevent the spread of the disease. The methods to eliminate infected caged laying hens are limited. An experiment was conducted to study the effectiveness of foam made from compressed air, water, and soap to kill laying hens in cages. The study found that stress levels of the hens killed using compressed air foam in cages to be similar to the hens killed by carbon dioxide or the negative control. Hens exposed to carbon dioxide died earlier as compared to the foam methods. The authors conclude that application of compressed air foam in cages is an alternative to methods such as gas inhalation and ventilation shutdown to rapidly and humanely kill laying hens during epidemics. Abstract During the 2014–2015 US highly pathogenic avian influenza (HPAI) outbreak, 50.4 million commercial layers and turkeys were affected, resulting in economic losses of $3.3 billion. Rapid depopulation of infected poultry is vital to contain and eradicate reportable diseases like HPAI. The hypothesis of the experiment was that a compressed air foam (CAF) system may be used as an alternative to carbon dioxide (CO2) inhalation for depopulating caged layer hens. The objective of this study was to evaluate corticosterone (CORT) and time to cessation of movement (COM) of hens subjected to CAF, CO2 inhalation, and negative control (NEG) treatments. In Experiment 1, two independent trials were conducted using young and spent hens. Experiment 1 consisted of five treatments: NEG, CO2 added to a chamber, a CO2 pre-charged chamber, CAF in cages, and CAF in a chamber. In Experiment 2, only spent hens were randomly assigned to three treatments: CAF in cages, CO2 added to a chamber, and aspirated foam. Serum CORT levels of young hens were not significantly different among the CAF in cages, CAF in a chamber, NEG control, and CO2 inhalation treatments. However, spent hens subjected to the CAF in a chamber had significantly higher CORT levels than birds in the rest of the treatments. Times to COM of spent hens subjected to CAF in cages and aspirated foam were significantly greater than of birds exposed to the CO2 in a chamber treatment. These data suggest that applying CAF in cages is a viable alternative for layer hen depopulation during a reportable disease outbreak. PMID:29324639

Depopulation of Caged Layer Hens with a Compressed Air Foam System.

PubMed

Gurung, Shailesh; Hoffman, John; Stringfellow, Kendre; Abi-Ghanem, Daad; Zhao, Dan; Caldwell, David; Lee, Jason; Styles, Darrel; Berghman, Luc; Byrd, James; Farnell, Yuhua; Archer, Gregory; Farnell, Morgan

2018-01-11

During the 2014-2015 US highly pathogenic avian influenza (HPAI) outbreak, 50.4 million commercial layers and turkeys were affected, resulting in economic losses of $3.3 billion. Rapid depopulation of infected poultry is vital to contain and eradicate reportable diseases like HPAI. The hypothesis of the experiment was that a compressed air foam (CAF) system may be used as an alternative to carbon dioxide (CO₂) inhalation for depopulating caged layer hens. The objective of this study was to evaluate corticosterone (CORT) and time to cessation of movement (COM) of hens subjected to CAF, CO₂ inhalation, and negative control (NEG) treatments. In Experiment 1, two independent trials were conducted using young and spent hens. Experiment 1 consisted of five treatments: NEG, CO₂ added to a chamber, a CO₂ pre-charged chamber, CAF in cages, and CAF in a chamber. In Experiment 2, only spent hens were randomly assigned to three treatments: CAF in cages, CO₂ added to a chamber, and aspirated foam. Serum CORT levels of young hens were not significantly different among the CAF in cages, CAF in a chamber, NEG control, and CO₂ inhalation treatments. However, spent hens subjected to the CAF in a chamber had significantly higher CORT levels than birds in the rest of the treatments. Times to COM of spent hens subjected to CAF in cages and aspirated foam were significantly greater than of birds exposed to the CO₂ in a chamber treatment. These data suggest that applying CAF in cages is a viable alternative for layer hen depopulation during a reportable disease outbreak.

Proliferative kidney disease in brown trout: infection level, pathology and mortality under field conditions.

PubMed

Schmidt-Posthaus, Heike; Hirschi, Regula; Schneider, Ernst

2015-05-21

Proliferative kidney disease (PKD) is an emerging disease threatening wild salmonid populations. In temperature-controlled aquaria, PKD can cause mortality rates of up to 85% in rainbow trout. So far, no data about PKD-related mortality in wild brown trout Salmo trutta fario are available. The aim of this study was to investigate mortality rates and pathology in brown trout kept in a cage within a natural river habitat known to harbor Tetracapsuloides bryosalmonae. Young-of-the-year (YOY) brown trout, free of T. bryosalmonae, were exposed in the River Wutach, in the northeast of Switzerland, during 3 summer months. Samples of wild brown trout caught by electrofishing near the cage location were examined in parallel. The incidence of PKD in cage-exposed animals (69%) was not significantly different to the disease prevalence of wild fish (82 and 80% in the upstream and downstream locations, respectively). The mortality in cage-exposed animals, however, was as low as 15%. At the termination of the exposure experiment, surviving fish showed histological lesions typical for PKD regression, suggesting that many YOY brown trout survive the initial infection. Our results at the River Wutach suggest that PKD in brown trout does not always result in high mortality under natural conditions.

Cage Change Influences Serum Corticosterone and Anxiety-Like Behaviors in the Mouse

PubMed Central

Rasmussen, Skye; Miller, Melinda M.; Filipski, Sarah B.; Tolwani, Ravi J.

2011-01-01

Environmental variables and husbandry practices can influence physiology and alter behavior in mice. Our study evaluated the effects of cage change on serum corticosterone levels and anxiety-like behaviors in C57BL/6 male mice. We examined the effects of 3 different methods of performing cage transfer and of transferring mice to a clean or a dirty familiar cage microenvironment. The 3 different handling methods were forceps transfer, gentle transfer with gloved hands, and a passive transfer technique that did not involve active handling. Active handling methods and transfer to both clean and dirty cage microenvironments significantly increased serum corticosterone 15 min after cage change; however, at 60 min after cage change, levels were comparable to those of unmanipulated mice. Although the effects were transient, cage change altered anxiety-like behaviors in the open field when behavioral testing was performed on the same day. These results demonstrate that the timing of cage change can influence behavioral results, an effect that is an important consideration for rodent behavioral studies. PMID:21838975

Numerical study on the hydrodynamic characteristics of biofouled full-scale net cage

NASA Astrophysics Data System (ADS)

Bi, Chun-wei; Zhao, Yun-peng; Dong, Guo-hai

2015-06-01

The effect of biofouling on the hydrodynamic characteristics of the net cage is of particular interest as biofouled nettings can significantly reduce flow of well-oxygenated water reaching the stocked fish. For computational efficiency, the porous-media fluid model is proposed to simulate flow through the biofouled plane net and full-scale net cage. The porous coefficients of the porous-media fluid model can be determined from the quadratic-function relationship between the hydrodynamic forces on a plane net and the flow velocity using the least squares method. In this study, drag forces on and flow fields around five plane nets with different levels of biofouling are calculated by use of the proposed model. The numerical results are compared with the experimental data of Swift et al. (2006) and the effectiveness of the numerical model is presented. On that basis, flow through full-scale net cages with the same level of biofouling as the tested plane nets are modeled. The flow fields inside and around biofouled net cages are analyzed and the drag force acting on a net cage is estimated by a control volume analysis method. According to the numerical results, empirical formulas of reduction in flow velocity and load on a net cage are derived as function of drag coefficient of the corresponding biofouled netting.

The effect of early life experience, environment, and genetic factors on spontaneous home-cage aggression-related wounding in male C57BL/6 mice.

PubMed

Gaskill, Brianna N; Stottler, Aurora M; Garner, Joseph P; Winnicker, Christina W; Mulder, Guy B; Pritchett-Corning, Kathleen R

2017-03-22

Aggression is a major welfare issue in mice, particularly when mice unfamiliar to each other are first placed in cages, as happens on receipt from a vendor, and following cage cleaning. Injuries from aggression are the second leading cause of unplanned euthanasia in mice, following ulcerative dermatitis. Commonly employed strategies for reducing aggression-related injury are largely anecdotal, and may even be counterproductive. Here we report a series of experiments testing potential explanations and interventions for post-shipping aggression-related injuries in C57BL/6 mice. First, we examined the effects of weaning: testing whether manipulating weaning age reduced aggression-related injuries, and if repeated mixing of weaned mice before shipping increased these injuries. Contrary to our predictions, repeated mixing did not increase post-shipping injurious aggression, and early weaning reduced aggression-related injuries. Second, we examined potential post-shipping interventions: testing whether lavender essential oil applied to the cage reduced aggression-related injuries, and whether a variety of enrichments decreased injurious aggression. Again, contrary to predictions, lavender increased wounding, and none of the enrichments reduced it. However, consistent with the effects of weaning age in the first experiment, cages with higher mean body weight showed elevated levels of aggression-related wounding. Finally, we tested whether C57BL/6 substrains and identification methods affected levels of intra-cage wounding from aggression. We found no effect of strain, but cages where mice were ear-notched for identification showed higher levels of wounding than cages where mice were tail-tattooed. Overall, these results emphasize the multifactorial nature of home-cage injurious aggression, and the importance of testing received wisdom when it comes to managing complex behavioral and welfare problems. In terms of practical recommendations to reduce aggressive wounding in the home cage, tail tattooing is recommended over ear notching and late weaning should be avoided.

Optical cage generated by azimuthal- and radial-variant vector beams.

PubMed

Man, Zhongsheng; Bai, Zhidong; Li, Jinjian; Zhang, Shuoshuo; Li, Xiaoyu; Zhang, Yuquan; Ge, Xiaolu; Fu, Shenggui

2018-05-01

We propose a method to generate an optical cage using azimuthal- and radial-variant vector beams in a high numerical aperture optical system. A new kind of vector beam that has azimuthal- and radial-variant polarization states is proposed and demonstrated theoretically. Then, an integrated analytical model to calculate the electromagnetic field and Poynting vector distributions of the input azimuthal- and radial-variant vector beams is derived and built based on the vector diffraction theory of Richards and Wolf. From calculations, a full polarization-controlled optical cage is obtained by simply tailoring the radial index of the polarization, the uniformity U of which is up to 0.7748, and the cleanness C is zero. Additionally, a perfect optical cage can be achieved with U=1, and C=0 by introducing an amplitude modulation; its magnetic field and energy flow are also demonstrated in detail. Such optical cages may be helpful in applications such as optical trapping and high-resolution imaging.

Thermometry in dielectrophoresis chips for contact-free cell handling

NASA Astrophysics Data System (ADS)

Jaeger, M. S.; Mueller, T.; Schnelle, T.

2007-01-01

Cell biology applications, protocols in immunology and stem cell research, require that individual cells are handled under strict control of their contacts to other cells or synthetic surfaces. Dielectrophoresis (DEP) in microfluidic chips is an established technique to investigate, group, wash, cultivate and sort cells contact-free under physiological conditions: microelectrode octode cages, versatile dielectrophoretic elements energized with radio frequency electric fields, stably trap single cells or cellular aggregates. For medical applications and cell cultivation, possible side effects of the dielectrophoretic manipulation, such as membrane polarization and Joule heating, have to be quantified. Therefore, we characterized the electric field-induced warming in dielectrophoretic cages using ohmic resistance measurements, fluorometry, liquid crystal beads, infra-red thermography and bubble size thermometry. We compare the results of these techniques with respect to the influences of voltage, electric conductivity of buffer, frequency, cage size and electrode surface. We conclude that in the culture medium thermal effects may be neglected if low voltages and an electric field-reducing phase pattern are used. Our experimental results provide explicit values for estimating the thermal effect on dielectrophoretically caged cells and show that Joule heating is best minimized by optimizing the cage geometry and reducing the buffer conductivity. The results may additionally serve to evaluate and improve theoretical predictions on field-induced effects. Based on present-day chip processing possibilities, DEP is well suited for the manipulation of cells.

International standardization of cage designs and feeding regimes for honey bee in vitro experiments

USDA-ARS?s Scientific Manuscript database

The aim of this study was to improve and standardize cage systems for maintaining adult honey bee workers under in vitro laboratory conditions. To achieve this goal, we experimentally evaluated the impact of different cages, developed by scientists of the international research network COLOSS (Preve...

Evaluation of cage designs and feeding regimes for honey bee (Hymenoptera: Apidae) laboratory experiments.

PubMed

Huang, Shao Kang; Csaki, Tamas; Doublet, Vincent; Dussaubat, Claudia; Evans, Jay D; Gajda, Anna M; Gregorc, Alex; Hamilton, Michele C; Kamler, Martin; Lecocq, Antoine; Muz, Mustafa N; Neumann, Peter; Ozkirim, Asli; Schiesser, Aygün; Sohr, Alex R; Tanner, Gina; Tozkar, Cansu Ozge; Williams, Geoffrey R; Wu, Lyman; Zheng, Huoqing; Chen, Yan Ping

2014-02-01

The aim of this study was to improve cage systems for maintaining adult honey bee (Apis mellifera L.) workers under in vitro laboratory conditions. To achieve this goal, we experimentally evaluated the impact of different cages, developed by scientists of the international research network COLOSS (Prevention of honey bee COlony LOSSes), on the physiology and survival of honey bees. We identified three cages that promoted good survival of honey bees. The bees from cages that exhibited greater survival had relatively lower titers of deformed wing virus, suggesting that deformed wing virus is a significant marker reflecting stress level and health status of the host. We also determined that a leak- and drip-proof feeder was an integral part of a cage system and a feeder modified from a 20-ml plastic syringe displayed the best result in providing steady food supply to bees. Finally, we also demonstrated that the addition of protein to the bees' diet could significantly increase the level ofvitellogenin gene expression and improve bees' survival. This international collaborative study represents a critical step toward improvement of cage designs and feeding regimes for honey bee laboratory experiments.

Field-cage methodology for evaluating climatic suitability for introduced wood-borer parasitoids: preliminary results from the emerald ash borer system

Treesearch

Michael D. Ulyshen; Jian J. Duan; Leah S. Bauer; Juli Gould; Phil Taylor; Dick Bean; Carol Holko; Roy Van Driesche

2011-01-01

Field-cage methods were developed to evaluate the abilities of Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) and Spathius agrili Yang (Hymenoptera: Braconidae), biocontrol agents of Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), to parasitize, develop and overwinter following three late-season releases at both a northern (Michigan) and a southern (...

Quantifying horizontal transmission of Nosema lymantriae, a microsporidian pathogen of the gypsy moth, Lymantria dispar (Lep., Lymantriidae) in field cage studies

Treesearch

Gernot Hoch; Vincent D' Amico; Leellen F. Solter; Milan Zubrik; Michael L. McManus

2008-01-01

Nosema lymantriae is a microsporidian pathogen of the gypsy moth, Lymantria dispar that has been documented to be at least partially responsible for the collapse of L. dispar outbreak populations in Europe. To quantify horizontal transmission of this pathogen under field conditions we performed caged-tree...

Agricultural wetlands as potential hotspots for mercury bioaccumulation: Experimental evidence using caged fish

USGS Publications Warehouse

Ackerman, Joshua T.; Eagles-Smith, Collin A.

2010-01-01

Wetlands provide numerous ecosystem services, but also can be sources of methylmercury (MeHg) production and export. Rice agricultural wetlands in particular may be important sites for MeHg bioaccumulation due to their worldwide ubiquity, periodic flooding schedules, and high use by wildlife. We assessed MeHg bioaccumulation within agricultural and perennial wetlands common to California's Central Valley during summer, when the majority of wetland habitats are shallowly flooded rice fields. We introduced caged western mosquitofish (Gambusia affinis) within white rice (Oryza sativa), wild rice (Zizania palustris), and permanent wetlands at water inlets, centers, and outlets. Total mercury (THg) concentrations and body burdens in caged mosquitofish increased rapidly, exceeding baseline values at introduction by 135% to 1197% and 29% to 1566% among sites, respectively, after only 60 days. Mercury bioaccumulation in caged mosquitofish was greater in rice fields than in permanent wetlands, with THg concentrations at wetland outlets increasing by 12.1, 5.8, and 2.9 times over initial concentrations in white rice, wild rice, and permanent wetlands, respectively. In fact, mosquitofish caged at white rice outlets accumulated 721 ng Hg/fish in just 60 days. Mercury in wild mosquito fish and Mississippi silversides (Menidia audens) concurrently sampled at wetland outlets also were greater in white rice and wild rice than permanent wetlands. Within wetlands, THg concentrations and body burdens of both caged and wild fish increased from water inlets to outlets in white rice fields, and tended to not vary among sites in permanent wetlands. Fish THg concentrations in agricultural wetlands were high, exceeding 0.2 ??g/g ww in 82% of caged fish and 59% of wild fish. Our results indicate that shallowly flooded rice fields are potential hotspots for MeHg bioaccumulation and, due to their global prevalence, suggest that agricultural wetlands may be important contributors to MeHg contamination.

Behavioral assessment of intermittent wheel running and individual housing in mice in the laboratory.

PubMed

Pham, Therese M; Brené, Stefan; Baumans, Vera

2005-01-01

Physical cage enrichment--exercise devices for rodents in the laboratory--often includes running wheels. This study compared responses of mice in enriched physical and social conditions and in standard social conditions to wheel running, individual housing, and open-field test. The study divided into 6 groups, 48 female BALB/c mice group housed in enriched and standard conditions. On alternate days, the study exposed 2 groups to individual running wheel cages. It intermittently separated from their cage mates and housed individually 2 groups with no running wheels; 2 control groups remained in enriched or standard condition cages. There were no significant differences between enriched and standard group housed mice in alternate days' wheel running. Over time, enriched, group housed mice ran less. Both groups responded similarly to individual housing. In open-field test, mice exposed to individual housing without running wheel moved more and faster than wheel running and home cage control mice. They have lower body weights than group housed and wheel running mice. Intermittent withdrawal of individual housing affects the animals more than other commodities. Wheel running normalizes some effects of intermittent separation from the enriched, social home cage.

Evaluation of insecticidal activity of a bacterial strain, Serratia sp. EML-SE1 against diamondback moth.

PubMed

Jeong, Hyung Uk; Mun, Hye Yeon; Oh, Hyung Keun; Kim, Seung Bum; Yang, Kwang Yeol; Kim, Iksoo; Lee, Hyang Burm

2010-08-01

To identify novel bioinsecticidal agents, a bacterial strain, Serratia sp. EML-SE1, was isolated from a dead larva of the lepidopteran diamondback moth (Plutella xylostella) collected from a cabbage field in Korea. In this study, the insecticidal activity of liquid cultures in Luria-Bertani broth (LBB) and nutrient broth (NB) of a bacterial strain, Serratia sp. EML-SE1 against thirty 3rd and 4th instar larvae of the diamondback moth was investigated on a Chinese cabbage leaf housed in a round plastic cage (Ø 10 x 6 cm). 72 h after spraying the cabbage leaf with LBB and NB cultures containing the bacterial strain, the mortalities of the larvae were determined to be 91.7% and 88.3%, respectively. In addition, the insecticidal activity on potted cabbage containing 14 leaves in a growth cage (165 x 83 x 124 cm) was found to be similar to that of the plastic cage experiment. The results of this study provided valuable information on the insecticidal activity of the liquid culture of a Serratia species against the diamondback moth.

Caging, but not air deprivation, slows tadpole growth and development in the amphibian Xenopus laevis.

PubMed

Rose, Christopher S

2014-08-01

Xenopus laevis tadpoles raised in submerged cages in normoxic water develop more slowly than tadpoles raised with access to air. This study distinguishes between the effects of being caged and being deprived access to air on development and growth. Tadpoles were raised in high and low density control tanks and in cages in the same tank that were either completely submerged or with the top exposed to air. Experiments were repeated with the cages in different positions relative to the air stones and with and without the water flow from air stones supplemented with a pump. Whereas caging tadpoles has a large effect on their development and growth, additionally depriving them of air has a small effect and this effect can be removed by optimizing water flow through the cage. The effect of caging, though significant in this study, is small compared to the variation in growth and developmental rates that is commonly encountered within and among controls in lab studies. Caging effects can also be diminished by optimizing rearing conditions and/or having exceptionally vigorous tadpoles. The effects of air deprivation and caging thus pose less of a problem for experimenting on air-deprived (AD) and air-restored Xenopus tadpoles than their inherent variability in growth and developmental rates and their susceptibility to growth and developmental arrest. Further, the effect of air deprivation in this air-breathing amphibian does not pose a conflict with evolutionary hypotheses for lung loss involving lengthening of the larval period and delay in the onset of air breathing. © 2014 Wiley Periodicals, Inc.

Effects of an oil production effluent on gametogenesis and gamete performance in the purple sea urchin (Strongylocentrotus purpuratus Stimpson)

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

Krause, P.R.

1994-07-01

Adult organisms subjected to chronic discharges from a point source of pollution may exhibit several sublethal responses. One such response is the impairment of gamete production. This may be expressed in the amount and/or quality of gametes produced by adults. In this study the effects of chronic exposure to produced water (an oil production effluent) on the gametogenesis and gamete performance of the purple sea urchin (Strongylocentrotus purpuratus Stimpson) were examined using an in situ caging experiment. Adult purple sea urchins were kept in benthic cages arrayed down-field from a discharging diffuser at 13 sites, with distances ranging from 5more » to 1,000 m. Cage exposures were maintained in the field for eight weeks, and each cage held 25 animals. Gametogenesis was examined for each sex by comparing a size-independent measure of relative gonads ass as determined by analysis of covariance. Results showed that there was a significant negative relationship between these estimates of relative gonad mass and distance from the outfall for both sexes, indicating that sea urchins living closer to the outfall produced significantly larger gonads. Gamete performance was measured through a fertilization kinetics bioassay that held the concentration of eggs constant and varied the amount of sperm added. The proportion of eggs fertilized under each sperm concentration was determined and the response fit to a model of fertilizability showed a positive relationship with distance away from the outfall. These findings indicate that although adult sea urchins exposed to a produced water outfall exhibit larger gonads, they suffer a marked decrease in a gamete performance.« less

Survey of egg farmers regarding the ban on conventional cages in the EU and their opinion of alternative layer housing systems in Flanders, Belgium.

PubMed

Stadig, L M; Ampe, B A; Van Gansbeke, S; Van den Bogaert, T; D'Haenens, E; Heerkens, J L T; Tuyttens, F A M

2016-03-01

On 1 January 2012, conventional cages for laying hens were banned in the European Union (EU); all egg farmers must now use alternative hen housing systems. In total, 218 Flemish egg farmers were surveyed in 2013 to 2014 regarding which housing systems they currently use, their degree of satisfaction with the system, and how they experienced the transition from conventional cages to an alternative system. The response rate was 58.3% (127 respondents). Of these, 43 (33.9%) were no longer active as an egg farmer, mainly due to the ban on conventional cages. The respondents who were active as egg farmers both before and after the transition (84, 66.1%) mainly judged the ban as negative for their own finances and for the competitive position of the Belgian egg industry, but were neutral or positive regarding the general consequences for their own business. Most respondents' hens were housed in either aviary systems (47.7%) or in alternative cage systems (38.2%). When choosing a new system, the fit into the farm and consumer demand were the most important factors. Consumer demand was the main reason for choosing a system with free-range access. In general, egg farmers were satisfied with the system they chose, although this differs between systems. When asked to compare the alternative systems to conventional cages, alternatives were judged to be better for hen welfare and consumer demand, but similar or worse for all other aspects, especially labor. Egg farmers previously using conventional cages judged alternative systems more negatively than those who had no prior experience with conventional cages. Farmers who had experience with free-range systems judged these more positively than those without this experience, e.g., for egg consumer demand, profitability, and hen welfare. These results can possibly be extrapolated to other EU countries in which conventional cages were the most common housing system until 2012, and lessons can be drawn from the farmers' experiences when implementing other animal welfare legislation that may require similar far-reaching adaptations for primary production. © 2015 Poultry Science Association Inc.

The effect of pesticide residue on caged mosquito bioassays.

PubMed

Barber, J A S; Greer, Mike; Coughlin, Jamie

2006-09-01

Wind tunnel experiments showed that secondary pickup of insecticide residue by mosquitoes in cage bioassays had a significant effect on mortality. Cage bioassays using adult Ochlerotatus taeniorhynchus (Wiedemann) investigated the effect of exposure time to a contaminated surface. Cages were dosed in a wind tunnel using the LC50 for naled (0.124 mg a.i./ml) and an LC25 (0.0772 mg a.i./ml) for naled. Half of the bioassay mosquitoes were moved directly into clean cages with the other half remaining in the sprayed, hence contaminated, cage. Treatment mortality was assessed at 8, 15, 30, 60, 120, 240, and 1,440 min postapplication. Cage contamination had a significant effect on mosquito mortality for both the LC25 and LC50 between 15 and 30 min postapplication.

Reducing Mouse Anxiety during Handling: Effect of Experience with Handling Tunnels

PubMed Central

Gouveia, Kelly; Hurst, Jane L.

2013-01-01

Handling stress is a well-recognised source of variation in animal studies that can also compromise the welfare of research animals. To reduce background variation and maximise welfare, methods that minimise handling stress should be developed and used wherever possible. Recent evidence has shown that handling mice by a familiar tunnel that is present in their home cage can minimise anxiety compared with standard tail handling. As yet, it is unclear whether a tunnel is required in each home cage to improve response to handling. We investigated the influence of prior experience with home tunnels among two common strains of laboratory mice: ICR(CD-1) and C57BL/6. We compared willingness to approach the handler and anxiety in an elevated plus maze test among mice picked up by the tail, by a home cage tunnel or by an external tunnel shared between cages. Willingness to interact with the handler was much greater for mice handled by a tunnel, even when this was unfamiliar, compared to mice picked up by the tail. Once habituated to handling, C57BL/6 mice were most interactive towards a familiar home tunnel, whereas the ICR strain showed strong interaction with all tunnel handling regardless of any experience of a home cage tunnel. Mice handled by a home cage or external tunnel showed less anxiety in an elevated plus maze than those picked up by the tail. This study shows that using a tunnel for routine handling reduces anxiety among mice compared to tail handling regardless of prior familiarity with tunnels. However, as home cage tunnels can further improve response to handling in some mice, we recommend that mice are handled with a tunnel provided in their home cage where possible as a simple practical method to minimise handling stress. PMID:23840458

Reducing mouse anxiety during handling: effect of experience with handling tunnels.

PubMed

Gouveia, Kelly; Hurst, Jane L

2013-01-01

Handling stress is a well-recognised source of variation in animal studies that can also compromise the welfare of research animals. To reduce background variation and maximise welfare, methods that minimise handling stress should be developed and used wherever possible. Recent evidence has shown that handling mice by a familiar tunnel that is present in their home cage can minimise anxiety compared with standard tail handling. As yet, it is unclear whether a tunnel is required in each home cage to improve response to handling. We investigated the influence of prior experience with home tunnels among two common strains of laboratory mice: ICR(CD-1) and C57BL/6. We compared willingness to approach the handler and anxiety in an elevated plus maze test among mice picked up by the tail, by a home cage tunnel or by an external tunnel shared between cages. Willingness to interact with the handler was much greater for mice handled by a tunnel, even when this was unfamiliar, compared to mice picked up by the tail. Once habituated to handling, C57BL/6 mice were most interactive towards a familiar home tunnel, whereas the ICR strain showed strong interaction with all tunnel handling regardless of any experience of a home cage tunnel. Mice handled by a home cage or external tunnel showed less anxiety in an elevated plus maze than those picked up by the tail. This study shows that using a tunnel for routine handling reduces anxiety among mice compared to tail handling regardless of prior familiarity with tunnels. However, as home cage tunnels can further improve response to handling in some mice, we recommend that mice are handled with a tunnel provided in their home cage where possible as a simple practical method to minimise handling stress.

Effects of the Insect Growth Regulator, Novaluron on Immature Alfalfa Leafcutting Bees, Megachile rotundata

PubMed Central

Hodgson, Erin W.; Pitts-Singer, Theresa L.; Barbour, James D.

2011-01-01

Alfalfa leafcutting bees, Megachile rotundata F. (Hymenoptera: Megachilidae), are the most common pollinators of alfalfa in the Pacific Northwest. Reports from users of M. rotundata in Idaho, Utah and Colorado have indicated exceptionally poor bee return from fields treated with novaluron to control Lygus spp. Our goal was to evaluate novaluron toxicity to immature M. rotundata using two different possible mechanisms of exposure. One goal was to assess immature mortality via treating nectar-pollen provisions and adults with novaluron. Immature M. rotundata mortality in all novaluron provision dosing treatments was significantly higher than the water or blank controls, providing evidence that novaluron is toxic to progeny in nest cells. The mean cumulative frequency showed that more eggs and 1st–2nd instars died compared to older instars. Female M. rotundata nested similarly in field cages during the field cage experiment; however, there was greater immature mortality in cages where females were fed sugar-water + novaluron compared to sugar-water only. Although females provided adequate provisions, there was a low percentage of egg hatch and larval development when females ingested novaluron before mating and nesting. Novaluron was also present in egg provision of bees collecting resources from novaluron-sprayed plants. At least 84% of progeny died when the females were allowed to mate and nest 24 hours after a novaluron application. Novaluron could be contributing to poor bee return in alfalfa grown for seed. Timely insecticide applications to suppress Lygus spp. is an important consideration to improve ongoing bee health. PMID:21539417

Common experience modifies the reinforcing properties of methamphetamine-injected cage mates but not morphine-injected cage mates in C57 mice.

PubMed

Watanabe, Shigeru

2015-10-01

The aim of this study was to determine whether previous exposure to a drug affects the social facilitation of conditioned place preference (CPP) for a drug-injected cage mate. Twenty-two male C57/BL6J mice received drug injections (methamphetamine or morphine) and 22 male C57/BL6J mice received saline injections. All 44 mice then received CPP training, during which one compartment of a conventional CPP apparatus was associated with a drug-injected cage mate (stimulus mouse) and the other compartment was associated with a saline-injected cage mate (stimulus mouse). The subject mice did not receive any drug injection during this CPP training. Time spent in the compartment associated with the drug-injected cage mate was measured before and after training. Subject mice that had previously received methamphetamine injections showed an increase in the time spent in the compartment associated with the methamphetamine-injected cage mate after CPP training. This effect was not observed in subject mice that had previously received saline injections. Subject mice did not show an increase in the time spent in the compartment associated with the morphine-injected cage mate irrespective of whether they had previously received morphine or saline injections. Therefore, in agreement with previous reports, common experience with methamphetamine induced reinforcing properties, but that with morphine did not.

Preparation of a Cobalt(II) Cage: An Undergraduate Laboratory Experiment That Produces a ParaSHIFT Agent for Magnetic Resonance Spectroscopy

ERIC Educational Resources Information Center

Burns, Patrick J.; Tsitovich, Pavel B.; Morrow, Janet R.

2016-01-01

Laboratory experiments that demonstrate the effect of paramagnetic complexes on chemical shifts and relaxation times of protons are a useful way to introduce magnetic resonance spectroscopy (MRS) probes or magnetic resonance imaging (MRI) contrast agents. In this undergraduate inorganic chemistry experiment, a paramagnetic Co(II) cage complex is…

Rearing Laying Hens in Aviaries Reduces Fearfulness following Transfer to Furnished Cages

PubMed Central

Brantsæter, Margrethe; Tahamtani, Fernanda M.; Moe, Randi O.; Hansen, Tone B.; Orritt, Rachel; Nicol, Christine; Janczak, Andrew M.

2016-01-01

Appropriate rearing is essential for ensuring the welfare and productivity of laying hens. Early experience has the potential to affect the development of fearfulness. This study tested whether rearing in aviaries, as opposed to cages, reduces the fearfulness of laying hens after transfer to furnished cages. Fear responses were recorded as avoidance of a novel object in the home cage. Lohmann Selected Leghorns were reared in an aviary system or conventional rearing cages and then transported to furnished cages at 16 weeks, before the onset of lay. Observations of a selection of birds were conducted at 19 (N = 50 independent cages) and 21 (N = 48 independent cages) weeks of age. At 19 and 21 weeks, cage-reared birds showed higher levels of fearfulness indicated by spending more time away from the novel object compared to aviary-reared birds. These results suggest that rearing in an enriched aviary environment reduces fearfulness up to the fifth week after transfer to a new housing system, compared to rearing in cages. PMID:26955634

A novel test cage with an air ventilation system as an alternative to conventional cages for the efficacy testing of mosquito repellents.

PubMed

Obermayr, U; Rose, A; Geier, M

2010-11-01

We have developed a novel test cage and improved method for the evaluation of mosquito repellents. The method is compatible with the United States Environmental Protection Agency, 2000 draft OPPTS 810.3700 Product Performance Test Guidelines for Testing of Insect Repellents. The Biogents cages (BG-cages) require fewer test mosquitoes than conventional cages and are more comfortable for the human volunteers. The novel cage allows a section of treated forearm from a volunteer to be exposed to mosquito probing through a window. This design minimizes residual contamination of cage surfaces with repellent. In addition, an air ventilation system supplies conditioned air to the cages after each single test, to flush out and prevent any accumulation of test substances. During biting activity tests, the untreated skin surface does not receive bites because of a screen placed 150 mm above the skin. Compared with the OPPTS 810.3700 method, the BG-cage is smaller (27 liters, compared with 56 liters) and contains 30 rather than hundreds of blood-hungry female mosquitoes. We compared the performance of a proprietary repellent formulation containing 20% KBR3023 with four volunteers on Aedes aegypti (L.) (Diptera: Culicidae) in BG- and conventional cages. Repellent protection time was shorter in tests conducted with conventional cages. The average 95% protection time was 4.5 +/- 0.4 h in conventional cages and 7.5 +/- 0.6 h in the novel BG-cages. The protection times measured in BG-cages were more similar to the protection times determined with these repellents in field tests.

Wafer scale oblique angle plasma etching

DOEpatents

Burckel, David Bruce; Jarecki, Jr., Robert L.; Finnegan, Patrick Sean

2017-05-23

Wafer scale oblique angle etching of a semiconductor substrate is performed in a conventional plasma etch chamber by using a fixture that supports a multiple number of separate Faraday cages. Each cage is formed to include an angled grid surface and is positioned such that it will be positioned over a separate one of the die locations on the wafer surface when the fixture is placed over the wafer. The presence of the Faraday cages influences the local electric field surrounding each wafer die, re-shaping the local field to be disposed in alignment with the angled grid surface. The re-shaped plasma causes the reactive ions to follow a linear trajectory through the plasma sheath and angled grid surface, ultimately impinging the wafer surface at an angle. The selected geometry of the Faraday cage angled grid surface thus determines the angle at with the reactive ions will impinge the wafer.

Self-Assembly, Guest Capture, and NMR Spectroscopy of a Metal-Organic Cage in Water

ERIC Educational Resources Information Center

Go, Eun Bin; Srisuknimit, Veerasak; Cheng, Stephanie L.; Vosburg, David A.

2016-01-01

A green organic-inorganic laboratory experiment has been developed in which students prepare a self-assembling iron cage in D[subscript 2]O at room temperature. The tetrahedral cage captures a small, neutral molecule such as cyclohexane or tetrahydrofuran. [Superscript 1]H NMR analysis distinguishes captured and free guests through diagnostic…

Resistive field structures for semiconductor devices and uses therof

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

Marinella, Matthew; DasGupta, Sandeepan; Kaplar, Robert

The present disclosure relates to resistive field structures that provide improved electric field profiles when used with a semiconductor device. In particular, the resistive field structures provide a uniform electric field profile, thereby enhancing breakdown voltage and improving reliability. In example, the structure is a field cage that is configured to be resistive, in which the potential changes significantly over the distance of the cage. In another example, the structure is a resistive field plate. Using these resistive field structures, the characteristics of the electric field profile can be independently modulated from the physical parameters of the semiconductor device. Additionalmore » methods and architectures are described herein.« less

1/f Noise Inside a Faraday Cage

NASA Astrophysics Data System (ADS)

Handel, Peter H.; George, Thomas F.

2009-04-01

We show that quantum 1/f noise does not have a lower frequency limit given by the lowest free electromagnetic field mode in a Faraday cage, even in an ideal cage. Indeed, quantum 1/f noise comes from the infrared-divergent coupling of the field with the charges, in their joint nonlinear system, where the charges cause the field that reacts back on the charges, and so on. This low-frequency limitation is thus not applicable for the nonlinear system of matter and field in interaction. Indeed, this nonlinear system is governed by Newton's laws, Maxwell's equations, in general also by the diffusion equations for particles and heat, or reaction kinetics given by quantum matrix elements. Nevertheless, all the other quantities can be eliminated in principle, resulting in highly nonlinear integro-differential equations for the electromagnetic field only, which no longer yield a fundamental frequency. Alternatively, we may describe this through the presence of an infinite system of subharmonics. We show how this was proven early in the classical and quantum domains, adding new insight.

Effects of wind speed on aerosol spray penetration in adult mosquito bioassay cages.

PubMed

Hoffmann, W Clint; Fritz, Bradley K; Farooq, Muhammad; Cooperband, Miriam F

2008-09-01

Bioassay cages are commonly used to assess efficacy of insecticides against adult mosquitoes in the field. To correlate adult mortality readings to insecticidal efficacy and/or spray application parameters properly, it is important to know how the cage used in the bioassay interacts with the spray cloud containing the applied insecticide. This study compared the size of droplets, wind speed, and amount of spray material penetrating cages and outside of cages in a wind tunnel at different wind speeds. Two bioassay cages, Center for Medical, Agricultural and Veterinary Entomology (CMAVE) and Circle, were evaluated. The screen materials used on these cages reduced the size of droplets, wind speed, and amount of spray material inside the cages as compared to the spray cloud and wind velocity outside of the cages. When the wind speed in the dispersion tunnel was set at 0.6 m/sec (1.3 mph), the mean wind speed inside of the CMAVE Bioassay Cage and Circle Cage was 0.045 m/sec (0.10 mph) and 0.075 m/sec (0.17 mph), respectively. At air velocities of 2.2 m/sec (4.9 mph) in the dispersion tunnel, the mean wind speed inside of the CMAVE Bioassay Cage and Circle Cage was 0.83 m/sec (1.86 mph) and 0.71 m/sec (1.59 mph), respectively. Consequently, there was a consistent 50-70% reduction of spray material penetrating the cages compared to the spray cloud that approached the cages. These results provide a better understanding of the impact of wind speed, cage design, and construction on ultra-low-volume spray droplets.

Molecular dynamics simulation of framework flexibility effects on noble gas diffusion in HKUST-1 and ZIF-8

DOE PAGES

Parkes, Marie V.; Demir, Hakan; Teich-McGoldrick, Stephanie L.; ...

2014-03-28

Molecular dynamics simulations were used to investigate trends in noble gas (Ar, Kr, Xe) diffusion in the metal-organic frameworks HKUST-1 and ZIF-8. Diffusion occurs primarily through inter-cage jump events, with much greater diffusion of guest atoms in HKUST-1 compared to ZIF-8 due to the larger cage and window sizes in the former. We compare diffusion coefficients calculated for both rigid and flexible frameworks. For rigid framework simulations, in which the framework atoms were held at their crystallographic or geometry optimized coordinates, sometimes dramatic differences in guest diffusion were seen depending on the initial framework structure or the choice of frameworkmore » force field parameters. When framework flexibility effects were included, argon and krypton diffusion increased significantly compared to rigid-framework simulations using general force field parameters. Additionally, for argon and krypton in ZIF-8, guest diffusion increased with loading, demonstrating that guest-guest interactions between cages enhance inter-cage diffusion. No inter-cage jump events were seen for xenon atoms in ZIF-8 regardless of force field or initial structure, and the loading dependence of xenon diffusion in HKUST-1 is different for rigid and flexible frameworks. Diffusion of krypton and xenon in HKUST-1 depends on two competing effects: the steric effect that decreases diffusion as loading increases, and the “small cage effect” that increases diffusion as loading increases. Finally, a detailed analysis of the window size in ZIF-8 reveals that the window increases beyond its normal size to permit passage of a (nominally) larger krypton atom.« less

Dietary L-arginine supplementation attenuates lipopolysaccharide-induced inflammatory response in broiler chickens

USDA-ARS?s Scientific Manuscript database

Two experiments were conducted to investigate the effect of dietary L-arginine (Arg) supplementation on inflammatory response and innate immunity of broilers. Experiment 1 was designed as a 2 × 3 factorial arrangement (n = 8 cages/treatment; 6 birds/cage) with 3 dietary Arg concentrations (1.05, 1.4...

More vertical etch profile using a Faraday cage in plasma etching

NASA Astrophysics Data System (ADS)

Cho, Byeong-Ok; Hwang, Sung-Wook; Ryu, Jung-Hyun; Moon, Sang Heup

1999-05-01

Scanning electron microscope images of sidewalls obtained by plasma etching of an SiO2 film with and without a Faraday cage have been compared. When the substrate film is etched in the Faraday cage, faceting is effectively suppressed and the etch profile becomes more vertical regardless of the process conditions. This is because the electric potential in the cage is nearly uniform and therefore distortion of the electric field at the convex corner of a microfeature is prevented. The most vertical etch profile is obtained when the cage is used in fluorocarbon plasmas, where faceting is further suppressed due to the decrease in the chemical sputtering yield and the increase in the radical/ion flux on the substrate.

Filling-Fraction Fluctuation Leading to Glasslike Ultralow Thermal Conductivity in Caged Skutterudites

NASA Astrophysics Data System (ADS)

Ren, Wei; Geng, Huiyuan; Zhang, Zihao; Zhang, Lixia

2017-06-01

It is generally believed that filling atoms randomly and uniformly distribute in caged crystals, such as skutterudite compounds. Here, we report first-principles and experimental discovery of a multiscale filling-fraction fluctuation in the R Fe4Sb12 system. La0.8Ti0.1Ga0.1Fe4Sb12 spontaneously separates into La-rich and La-poor skutterudite phases, leading to multiscale strain field fluctuations. As a result, glasslike ultralow lattice thermal conductivity approaching the theoretical minimum is achieved, mainly due to strain field scattering of high-energy phonons. These findings reveal that an uneven distribution of filling atoms is efficient to further reduce the lattice thermal conductivity of caged crystals.

Walnut Twig Beetle (Coleoptera: Curculionidae: Scolytinae) Colonization of Eastern Black Walnut Nursery Trees

PubMed Central

Klingeman, William E.; Mayfield, Albert; Myers, Scott; Taylor, Adam

2017-01-01

Thousand cankers disease, caused by the invasive bark beetle Pityophthorus juglandis Blackman and an associated fungal pathogen Geosmithia morbida M.Kolařík, E. Freeland, C. Utley, N. Tisserat, currently threatens the health of eastern black walnut (Juglans nigra L.) in North America. Both the beetle and pathogen have expanded beyond their native range via transport of infested walnut wood. Geosmithia morbida can develop in seedlings following inoculation, but the ability of P. juglandis to colonize young, small diameter trees has not been investigated. This study assessed the beetle’s colonization behavior on J. nigra nursery trees. Beetles were caged directly onto the stems of walnut seedlings from five nursery sources representing a range of basal stem diameter classes. Seedlings were also exposed to P. juglandis in a limited choice, field-based experiment comparing pheromone-baited and unbaited stems. When beetles were caged directly onto stems, they probed and attempted to colonize seedlings across the range of diameters and across sources tested, including stems as small as 0.5 cm in diameter. In the field experiment, beetles only attempted to colonize seedlings that were baited with a pheromone lure and appeared to prefer (though not statistically significant) the larger diameter trees. Despite several successful penetrations into the phloem, there was no evidence of successful progeny development within the young trees in either experiment. Further investigation is recommended to better elucidate the risk nursery stock poses as a pathway for thousand cankers disease causal organisms. PMID:28973569

Effects of experience and cage enrichment on predatory skills of black-footed ferrets (Mustela nigripes)

USGS Publications Warehouse

Vargas, A.; Anderson, S.H.

1999-01-01

We studied ontogeny of predatory skills of growing black-footed ferrets (Mustela nigripes) raised under different captive conditions. To test effects of maturation, experience, and cage enrichment on predatory behavior, we exposed 70 juvenile black-footed ferrets to different numbers of live hamsters (Mesocricetus auratus) throughout development. Both maturation and experience increased the likelihood of a black-footed ferret making a successful kill. Black-footed ferrets exposed to greater environmental complexity (enriched cage, including encouragement of food-searching behaviors) also were more likely to kill than ferrets raised in a deprived environment. Behavioral studies of captive-raised black-footed ferrets can help refine current breeding techniques and ultimately enhance efforts to recover this endangered carnivore.

AN IMPROVED TRAP TO CAPTURE ADULT CONTAINER-INHABITING MOSQUITOES

PubMed Central

BARRERA, ROBERTO; MACKAY, ANDREW J.; AMADOR, MANUEL

2015-01-01

Although dengue viruses are thought to be transmitted by Aedes aegypti in Puerto Rico, Aedes mediovittatus, the Caribbean tree hole mosquito, is also a potential vector. This species is native to the Greater Antilles and has been shown to be a competent vector of dengue viruses in the laboratory. Consequently, it has been suggested that Ae. mediovittatus could be acting as a secondary vector or virus reservoir. This study was part of an ongoing investigation into this, and it aimed to determine whether BG-Sentinel traps (BGS traps) could be used to collect adults of this mosquito and could be modified to increase the number of captures of this species in the field. We conducted experiments to test the relative attractiveness of BGS traps to Ae. mediovittatus and Ae. aegypti and explored the effects of chemical lures (BG-Lure, CO2, octenol) and optical properties (color, size) on the capture rates of BGS traps in a large, outdoor cage in San Juan city, Puerto Rico. We also conducted field tests to compare modified BGS traps with the original traps in a rural community in Patillas municipality, Puerto Rico. Results obtained from the large, outdoor cage experiments indicated that trap captures of both mosquito species could be significantly enhanced by using black instead of white BGS traps combined with BG-Lure. Field experiments revealed that the modified traps captured a significantly greater number of Ae. aegypti, Ae. mediovittatus, and Culex quinquefasciatus, with greater sensitivity for the latter 2 species, and also captured a larger number of mosquito species and a smaller ratio of Ae. aegypti to Ae. mediovittatus, with greater than expected species co-occurrences. PMID:24551969

Macroalgae Inhibits Larval Settlement and Increases Recruit Mortality at Ningaloo Reef, Western Australia

PubMed Central

Van Keulen, Mike; Loneragan, Neil R.

2015-01-01

Globally, many coral reefs are degraded and demonstrate reduced coral cover and increased macroalgal abundance. While negative correlations between macroalgae and coral recruitment have commonly been documented, the mechanisms by which macroalgae affects recruitment have received little attention. Here we examined the effect of macroalgae on larval settlement and the growth and survival of coral recruits, in a field experiment over nine months. Exclusion treatments were used to manipulate herbivory and macroalgal biomass, while settlement tiles measured coral settlement and survival. After nine months the volume of macroalgae was up to 40 times greater in the caged treatments than in controls and the settlement of coral larvae on the undersides of tiles within caged plots was 93% lower than in the uncaged treatments. The growth and survival of coral recruits was also severely reduced in the presence of macroalgae: survival was 79% lower in caged treatments and corals were up to 58% smaller with 75% fewer polyps. These data indicate that macroalgae has an additive effect on coral recruitment by reducing larval settlement and increasing recruit mortality. This research demonstrates that macroalgae can not only inhibit coral recruitment, but also potentially maintain dominance through a positive feedback system. PMID:25898011

Effect of cage vs. floor litter environments on the pulmonary hypertensive response to intravenous endotoxin and on blood-gas values in broilers.

PubMed

Wang, W; Erf, G F; Wideman, R F

2002-11-01

Intravenous endotoxin has been shown to trigger a delayed pulmonary hypertensive response that varies widely in magnitude and duration among individual broilers. It was proposed that this individual variability may reflect immunological differences acquired during previous respiratory challenges that might have subsequently altered the endotoxin-initiated biochemical cascade. In Experiment 1, we tested the hypothesis that, when compared with broilers reared in clean stainless steel cages (Cage group), broilers reared on floor litter (Floor group) should experience a greater respiratory challenge and therefore may consistently exhibit a more enhanced pulmonary hypertensive response to intravenous endotoxin. Birds in the Cage group were grown in stainless steel cages at a low density (72 birds/8 m2 chamber), and fecal and dander materials were removed daily. Birds in the Floor group were reared on wood-shavings litter at a higher density (110 birds/8 m2 chamber). Pulmonary and systemic mean arterial pressures and blood-gas values were evaluated prior to and following the intravenous administration of 1 mg Salmonella typhimurium endotoxin. Broilers in the Floor and Cage groups exhibited pulmonary hypertensive responses to endotoxin that were very similar in terms of time of onset, duration, and magnitude, as well as variability in the response among individuals. Systemic hypotension also developed similarly in both groups following endotoxin injection. Blood-gas values indicated that the partial pressure of CO2 and the HCO3- concentration in arterial blood were higher (P < 0.05) in the Floor group than in the Cage group prior to and subsequent to the endotoxin injection. In Experiment 2, we reevaluated the effect of a dirty vs. a clean environment on blood-gas values using a different strain of broilers, and confirmed the negative impact of floor rearing on blood-gas values. We conclude that broilers reared on the floor inhaled litter dust and noxious fumes, which impaired pulmonary gas exchange and increased the arterial partial pressure of CO2 when compared with broilers reared in clean stainless steel cages. Nevertheless, the pulmonary hypertensive response to endotoxin did not differ between broilers reared on the floor and those in cages.

30 years of cosmic fullerenes

NASA Astrophysics Data System (ADS)

Berné, O.; Montillaud, J.; Mulas, G.; Joblin, C.

2015-12-01

In 1985, ``During experiments aimed at understanding the mechanisms by which long-chain carbon molecules are formed in interstellar space and circumstellar shells'', Harry Kroto and his collaborators serendipitously discovered a new form of carbon: fullerenes. The most emblematic fullerene (i.e. C_{60} ``buckminsterfullerene''), contains exactly 60 carbon atoms organized in a cage-like structure similar to a soccer ball. Since their discovery impacted the field of nanotechnologies, Kroto and colleagues received the Nobel prize in 1996. The cage-like structure, common to all fullerene molecules, gives them unique properties, in particular an extraordinary stability. For this reason and since they were discovered in experiments aimed to reproduce conditions in space, fullerenes were sought after by astronomers for over two decades, and it is only recently that they have been firmly identified by spectroscopy, in evolved stars and in the interstellar medium. This identification offered the opportunity to study the molecular physics of fullerenes in the unique physical conditions provided by space, and to make the link with other large carbonaceous molecules thought to be present in space : polycyclic aromatic hydrocarbons.

Acetylcholinesterase in honey bees (Apis mellifera) exposed to neonicotinoids, atrazine and glyphosate: laboratory and field experiments.

PubMed

Boily, Monique; Sarrasin, Benoit; Deblois, Christian; Aras, Philippe; Chagnon, Madeleine

2013-08-01

In Québec, as observed globally, abnormally high honey bee mortality rates have been reported recently. Several potential contributing factors have been identified, and exposure to pesticides is of increasing concern. In maize fields, foraging bees are exposed to residual concentrations of insecticides such as neonicotinoids used for seed coating. Highly toxic to bees, neonicotinoids are also reported to increase AChE activity in other invertebrates exposed to sub-lethal doses. The purpose of this study was therefore to test if the honey bee's AChE activity could be altered by neonicotinoid compounds and to explore possible effects of other common products used in maize fields: atrazine and glyphosate. One week prior to pollen shedding, beehives were placed near three different field types: certified organically grown maize, conventionally grown maize or non-cultivated. At the same time, caged bees were exposed to increasing sub-lethal doses of neonicotinoid insecticides (imidacloprid and clothianidin) and herbicides (atrazine and glyphosate) under controlled conditions. While increased AChE activity was found in all fields after 2 weeks of exposure, bees close to conventional maize crops showed values higher than those in both organic maize fields and non-cultivated areas. In caged bees, AChE activity increased in response to neonicotinoids, and a slight decrease was observed by glyphosate. These results are discussed with regard to AChE activity as a potential biomarker of exposure for neonicotinoids.

Solute diffusion through fibrotic tissue formed around protective cage system for implantable devices.

PubMed

Prihandana, Gunawan Setia; Ito, Hikaru; Tanimura, Kohei; Yagi, Hiroshi; Hori, Yuki; Soykan, Orhan; Sudo, Ryo; Miki, Norihisa

2015-08-01

This article presents the concept of an implantable cage system that can house and protect implanted biomedical sensing and therapeutic devices in the body. Cylinder-shaped cages made of porous polyvinyl alcohol (PVA) sheets with an 80-µm pore size and/or stainless steel meshes with 0.54-mm openings were implanted subcutaneously in the dorsal region of rats for 5 weeks. Analysis of the explanted cages showed the formation of fibrosis tissue around the cages. PVA cages had fibrotic tissue growing mostly along the outer surface of cages, while stainless steel cages had fibrotic tissue growing into the inside surface of the cage structure, due to the larger porosity of the stainless steel meshes. As the detection of target molecules with short time lags for biosensors and mass transport with low diffusion resistance into and out of certain therapeutic devices are critical for the success of such devices, we examined whether the fibrous tissue formed around the cages were permeable to molecules of our interest. For that purpose, bath diffusion and microfluidic chamber diffusion experiments using solutions containing the target molecules were performed. Diffusion of sodium, potassium and urea through the fibrosis tissue was confirmed, thus suggesting the potential of these cylindrical cages surrounded by fibrosis tissue to successfully encase implantable sensors and therapeutic apparatus. © 2014 Wiley Periodicals, Inc.

Influence of the cage on friction torque in low loaded thrust ball bearing operating in dry conditions

NASA Astrophysics Data System (ADS)

Olaru, D.; Balan, M. R.; Tufescu, A.

2016-08-01

The authors investigated analytically and experimentally the friction torque in a modified thrust ball bearing operating at very low axial load in dry conditions by using only three balls and a cage. The experiments were conducted by using spin-down methodology. The results evidenced the influence of the sliding friction between the cage and the balls on the total friction torque. It was concluded that at very low loads the friction between cage and balls in a thrust ball bearing has an important contribution on total friction torque.

Influence of prerelease experience on reintroduced black-footed ferrets (Mustela nigripes)

USGS Publications Warehouse

Biggins, D.E.; Vargas, A.; Godbey, J.L.; Anderson, S.H.

1999-01-01

Captive breeding is increasingly being used to create supplies of endangered animals for release into natural habitats, but rearing strategies vary and debates arise over which methods are most efficient. We assessed postrelease behaviors and survival of three groups of black-footed ferrets, each with different prerelease experience. Eighteen ferret kits ???60 days of age were moved with their dams from cages to 80-m2 outdoor pens with prairie dog burrows. These animals were compared to animals reared in standard cages (n = 72), some of which were given experience killing prairie dogs (n = 32). Ferrets were released onto white-tailed prairie dog (Cynomys leucurus) colonies in Wyoming, USA, in fall, 1992. Radio-tagged cage-reared ferrets made longer nightly moves and dispersed further from release sites than their pen-reared counterparts. The band return rate was 4-fold higher for pen-reared animals than for cage-reared animals during surveys conducted about 1 month after release. We recommend routine use of quasi-natural outdoor pens for prerelease conditioning of black-footed ferrets.

Tri-trophic insecticidal effects of African plants against cabbage pests.

PubMed

Amoabeng, Blankson W; Gurr, Geoff M; Gitau, Catherine W; Nicol, Helen I; Munyakazi, Louis; Stevenson, Phil C

2013-01-01

Botanical insecticides are increasingly attracting research attention as they offer novel modes of action that may provide effective control of pests that have already developed resistance to conventional insecticides. They potentially offer cost-effective pest control to smallholder farmers in developing countries if highly active extracts can be prepared simply from readily available plants. Field cage and open field experiments were conducted to evaluate the insecticidal potential of nine common Ghanaian plants: goat weed, Ageratum conyzoides (Asteraceae), Siam weed, Chromolaena odorata (Asteraceae), Cinderella weed, Synedrella nodiflora (Asteraceae), chili pepper, Capsicum frutescens (Solanaceae), tobacco, Nicotiana tabacum (Solanaceae) cassia, Cassia sophera (Leguminosae), physic nut, Jatropha curcas (Euphorbiaceae), castor oil plant, Ricinus communis (Euphorbiaceae) and basil, Ocimum gratissimum (Lamiaceae). In field cage experiments, simple detergent and water extracts of all botanical treatments gave control of cabbage aphid, Brevicoryne brassicae and diamondback moth, Plutella xylostella, equivalent to the synthetic insecticide Attack® (emamectin benzoate) and superior to water or detergent solution. In open field experiments in the major and minor rainy seasons using a sub-set of plant extracts (A. conyzoides, C. odorata, S. nodiflora, N. tabacum and R. communis), all controlled B. brassicae and P. xylostella more effectively than water control and comparably with or better than Attack®. Botanical and water control treatments were more benign to third trophic level predators than Attack®. Effects cascaded to the first trophic level with all botanical treatments giving cabbage head weights, comparable to Attack® in the minor season. In the major season, R. communis and A conyzoides treatment gave lower head yields than Attack® but the remaining botanicals were equivalent or superior to this synthetic insecticide. Simply-prepared extracts from readily-available Ghanaian plants give beneficial, tri-trophic benefits and merit further research as an inexpensive plant protection strategy for smallholder farmers in West Africa.

Tri-Trophic Insecticidal Effects of African Plants against Cabbage Pests

PubMed Central

Amoabeng, Blankson W.; Gurr, Geoff M.; Gitau, Catherine W.; Nicol, Helen I.; Stevenson, Phil C.

2013-01-01

Botanical insecticides are increasingly attracting research attention as they offer novel modes of action that may provide effective control of pests that have already developed resistance to conventional insecticides. They potentially offer cost-effective pest control to smallholder farmers in developing countries if highly active extracts can be prepared simply from readily available plants. Field cage and open field experiments were conducted to evaluate the insecticidal potential of nine common Ghanaian plants: goat weed, Ageratum conyzoides (Asteraceae), Siam weed, Chromolaena odorata (Asteraceae), Cinderella weed, Synedrella nodiflora (Asteraceae), chili pepper, Capsicum frutescens (Solanaceae), tobacco, Nicotiana tabacum (Solanaceae) cassia, Cassia sophera (Leguminosae), physic nut, Jatropha curcas (Euphorbiaceae), castor oil plant, Ricinus communis (Euphorbiaceae) and basil, Ocimum gratissimum (Lamiaceae). In field cage experiments, simple detergent and water extracts of all botanical treatments gave control of cabbage aphid, Brevicoryne brassicae and diamondback moth, Plutella xylostella, equivalent to the synthetic insecticide Attack® (emamectin benzoate) and superior to water or detergent solution. In open field experiments in the major and minor rainy seasons using a sub-set of plant extracts (A. conyzoides, C. odorata, S. nodiflora, N. tabacum and R. communis), all controlled B. brassicae and P. xylostella more effectively than water control and comparably with or better than Attack®. Botanical and water control treatments were more benign to third trophic level predators than Attack®. Effects cascaded to the first trophic level with all botanical treatments giving cabbage head weights, comparable to Attack® in the minor season. In the major season, R. communis and A conyzoides treatment gave lower head yields than Attack® but the remaining botanicals were equivalent or superior to this synthetic insecticide. Simply-prepared extracts from readily-available Ghanaian plants give beneficial, tri-trophic benefits and merit further research as an inexpensive plant protection strategy for smallholder farmers in West Africa. PMID:24205287

Experimental determination of a Viviparus contectus thermometry equation.

PubMed

Bugler, Melanie J; Grimes, Stephen T; Leng, Melanie J; Rundle, Simon D; Price, Gregory D; Hooker, Jerry J; Collinson, Margaret E

2009-09-01

Experimental measurements of the (18)O/(16)O isotope fractionation between the biogenic aragonite of Viviparus contectus (Gastropoda) and its host freshwater were undertaken to generate a species-specific thermometry equation. The temperature dependence of the fractionation factor and the relationship between Deltadelta(18)O (delta(18)O(carb.) - delta(18)O(water)) and temperature were calculated from specimens maintained under laboratory and field (collection and cage) conditions. The field specimens were grown (Somerset, UK) between August 2007 and August 2008, with water samples and temperature measurements taken monthly. Specimens grown in the laboratory experiment were maintained under constant temperatures (15 degrees C, 20 degrees C and 25 degrees C) with water samples collected weekly. Application of a linear regression to the datasets indicated that the gradients of all three experiments were within experimental error of each other (+/-2 times the standard error); therefore, a combined (laboratory and field data) correlation could be applied. The relationship between Deltadelta(18)O (delta(18)O(carb.) - delta(18)O(water)) and temperature (T) for this combined dataset is given by: T = - 7.43( + 0.87, - 1.13)*Deltadelta18O + 22.89(+/- 2.09) (T is in degrees C, delta(18)O(carb.) is with respect to Vienna Pee Dee Belemnite (VPDB) and delta(18)O(water) is with respect to Vienna Standard Mean Ocean Water (VSMOW). Quoted errors are 2 times standard error).Comparisons made with existing aragonitic thermometry equations reveal that the linear regression for the combined Viviparus contectus equation is within 2 times the standard error of previously reported aragonitic thermometry equations. This suggests there are no species-specific vital effects for Viviparus contectus. Seasonal delta(18)O(carb.) profiles from specimens retrieved from the field cage experiment indicate that during shell secretion the delta(18)O(carb.) of the shell carbonate is not influenced by size, sex or whether females contained eggs or juveniles. Copyright (c) 2009 John Wiley & Sons, Ltd.

Quantum dynamics of small H2 and D2 clusters in the large cage of structure II clathrate hydrate: Energetics, occupancy, and vibrationally averaged cluster structures

NASA Astrophysics Data System (ADS)

Sebastianelli, Francesco; Xu, Minzhong; Bačić, Zlatko

2008-12-01

We report diffusion Monte Carlo (DMC) calculations of the quantum translation-rotation (T-R) dynamics of one to five para-H2 (p-H2) and ortho-D2 (o-D2) molecules inside the large hexakaidecahedral (51264) cage of the structure II clathrate hydrate, which was taken to be rigid. These calculations provide a quantitative description of the size evolution of the ground-state properties, energetics, and the vibrationally averaged geometries, of small (p-H2)n and (o-D2)n clusters, n=1-5, in nanoconfinement. The zero-point energy (ZPE) of the T-R motions rises steeply with the cluster size, reaching 74% of the potential well depth for the caged (p-H2)4. At low temperatures, the rapid increase of the cluster ZPE as a function of n is the main factor that limits the occupancy of the large cage to at most four H2 or D2 molecules, in agreement with experiments. Our DMC results concerning the vibrationally averaged spatial distribution of four D2 molecules, their mean distance from the cage center, the D2-D2 separation, and the specific orientation and localization of the tetrahedral (D2)4 cluster relative to the framework of the large cage, agree very well with the low-temperature neutron diffraction experiments involving the large cage with the quadruple D2 occupancy.

Quantum dynamics of small H2 and D2 clusters in the large cage of structure II clathrate hydrate: energetics, occupancy, and vibrationally averaged cluster structures.

PubMed

Sebastianelli, Francesco; Xu, Minzhong; Bacić, Zlatko

2008-12-28

We report diffusion Monte Carlo (DMC) calculations of the quantum translation-rotation (T-R) dynamics of one to five para-H(2) (p-H(2)) and ortho-D(2) (o-D(2)) molecules inside the large hexakaidecahedral (5(12)6(4)) cage of the structure II clathrate hydrate, which was taken to be rigid. These calculations provide a quantitative description of the size evolution of the ground-state properties, energetics, and the vibrationally averaged geometries, of small (p-H(2))(n) and (o-D(2))(n) clusters, n=1-5, in nanoconfinement. The zero-point energy (ZPE) of the T-R motions rises steeply with the cluster size, reaching 74% of the potential well depth for the caged (p-H(2))(4). At low temperatures, the rapid increase of the cluster ZPE as a function of n is the main factor that limits the occupancy of the large cage to at most four H(2) or D(2) molecules, in agreement with experiments. Our DMC results concerning the vibrationally averaged spatial distribution of four D(2) molecules, their mean distance from the cage center, the D(2)-D(2) separation, and the specific orientation and localization of the tetrahedral (D(2))(4) cluster relative to the framework of the large cage, agree very well with the low-temperature neutron diffraction experiments involving the large cage with the quadruple D(2) occupancy.

Effects of Furnished Cage Type on Behavior and Welfare of Laying Hens.

PubMed

Li, Xiang; Chen, Donghua; Li, Jianhong; Bao, Jun

2016-06-01

This study was conducted to compare the effects of layout of furniture (a perch, nest, and sandbox) in cages on behavior and welfare of hens. Two hundred and sixteen Hyline Brown laying hens were divided into five groups (treatments) with four replicates per group: small furnished cages (SFC), medium furnished cages type I (MFC-I), medium furnished cages type II (MFC-II), and medium furnished cages type III (MFC-III) and conventional cages (CC). The experiment started at 18 week of age and finished at 52 week of age. Hens' behaviors were filmed during the following periods: 8:00 to 10:00; 13:00 to 14:00; 16:00 to 17:00 on three separate days and two hens from each cage were measured for welfare parameters at 50 wk of age. The results showed that feeding and laying of all hens showed no effect by cage type (p>0.05), and the hens in the furnished cages had significantly lower standing and higher walking than CC hens (p<0.05). The birds in MFC-III had significant higher preening, scratching and feather-pecking behavior than in the other cages (p<0.05). No difference in nesting behavior was found in the hens between the furnished cages (p>0.05). The hens in MFC-I, -II, and -III showed a significant higher socializing behavior than SFC and CC (p<0.05). The lowest perching was for the hens in SFC and the highest perching found for the hens in MFC-III. Overall, the hens in CC showed poorer welfare conditions than the furnished cages, in which the feather condition score, gait score and tonic immobility duration of the hens in CC was significantly higher than SFC, MFC-I, MFC-II, and MFC-III (p<0.05). In conclusion, the furnished cage design affected both behavior and welfare states of hens. Overall, MFC-III cage design was better than SFC, MFC-I, and MFC-II cage designs.

Effects of Furnished Cage Type on Behavior and Welfare of Laying Hens

PubMed Central

Li, Xiang; Chen, Donghua; Li, Jianhong; Bao, Jun

2016-01-01

This study was conducted to compare the effects of layout of furniture (a perch, nest, and sandbox) in cages on behavior and welfare of hens. Two hundred and sixteen Hyline Brown laying hens were divided into five groups (treatments) with four replicates per group: small furnished cages (SFC), medium furnished cages type I (MFC-I), medium furnished cages type II (MFC-II), and medium furnished cages type III (MFC-III) and conventional cages (CC). The experiment started at 18 week of age and finished at 52 week of age. Hens’ behaviors were filmed during the following periods: 8:00 to 10:00; 13:00 to 14:00; 16:00 to 17:00 on three separate days and two hens from each cage were measured for welfare parameters at 50 wk of age. The results showed that feeding and laying of all hens showed no effect by cage type (p>0.05), and the hens in the furnished cages had significantly lower standing and higher walking than CC hens (p<0.05). The birds in MFC-III had significant higher preening, scratching and feather-pecking behavior than in the other cages (p<0.05). No difference in nesting behavior was found in the hens between the furnished cages (p>0.05). The hens in MFC-I, −II, and −III showed a significant higher socializing behavior than SFC and CC (p<0.05). The lowest perching was for the hens in SFC and the highest perching found for the hens in MFC-III. Overall, the hens in CC showed poorer welfare conditions than the furnished cages, in which the feather condition score, gait score and tonic immobility duration of the hens in CC was significantly higher than SFC, MFC-I, MFC-II, and MFC-III (p<0.05). In conclusion, the furnished cage design affected both behavior and welfare states of hens. Overall, MFC-III cage design was better than SFC, MFC-I, and MFC-II cage designs. PMID:26954171

Field-Cage Methodology for Evaluating Climatic Suitability for Introduced Wood-Borer Parasitoids: Preliminary Results from the Emerald Ash Borer System

PubMed Central

Ulyshen, Michael D.; Duan, Jian J.; Bauer, Leah S.; Gould, Juli; Taylor, Phil; Bean, Dick; Holko, Carol; Driesche, Roy Van

2011-01-01

Field-cage methods were developed to evaluate the abilities of Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) and Spathius agrili Yang (Hymenoptera: Braconidae), biocontrol agents of Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), to parasitize, develop and overwinter following three late-season releases at both a northern (Michigan) and a southern (Maryland) location within the current North American range of A. planipennis. In August, September and October of 2009, five young green ash trees were selected at each location. Tetrastichus planipennisi and S. agrili were each randomly assigned to one of two cages attached to each tree, surrounding separate sections of trunk in which late-instar A. planipennis had been inserted. The following April, the caged trunk sections were dissected to determine the fate of each A. planipennis larva and the developmental stages of all recovered parasitoid progeny. At both locations, T. planipennisi and S. agrili were able to parasitize hosts and successfully overwinter (i.e., reach adulthood the following spring). For T. planipennisi, successful parasitism (i.e., parasitoid progeny reached adulthood) occurred for all caged releases in Maryland, but only for the August and September releases in Michigan. At both locations, percent parasitism by T. planipennisi was higher in August and September than in October. For S. agrili, successful parasitism occurred for all caged releases in Maryland, but only for the August release in Michigan. In Maryland, percent parasitism by S. agrili in August and September was higher than in October. The caging method described here should be useful in determining the climatic suitability of other regions before proceeding with large-scale releases of either species and may have utility in other wood-borer parasitoid systems as well. PMID:22233133

Field-cage methodology for evaluating climatic suitability for introduced wood-borer parasitoids: preliminary results from the emerald ash borer system.

PubMed

Ulyshen, Michael D; Duan, Jian J; Bauer, Leah S; Gould, Juli; Taylor, Phil; Bean, Dick; Holko, Carol; Van Driesche, Roy

2011-01-01

Field-cage methods were developed to evaluate the abilities of Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) and Spathius agrili Yang (Hymenoptera: Braconidae), biocontrol agents of Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), to parasitize, develop and overwinter following three late-season releases at both a northern (Michigan) and a southern (Maryland) location within the current North American range of A. planipennis. In August, September and October of 2009, five young green ash trees were selected at each location. Tetrastichus planipennisi and S. agrili were each randomly assigned to one of two cages attached to each tree, surrounding separate sections of trunk in which late-instar A. planipennis had been inserted. The following April, the caged trunk sections were dissected to determine the fate of each A. planipennis larva and the developmental stages of all recovered parasitoid progeny. At both locations, T. planipennisi and S. agrili were able to parasitize hosts and successfully overwinter (i.e., reach adulthood the following spring). For T. planipennisi, successful parasitism (i.e., parasitoid progeny reached adulthood) occurred for all caged releases in Maryland, but only for the August and September releases in Michigan. At both locations, percent parasitism by T. planipennisi was higher in August and September than in October. For S. agrili, successful parasitism occurred for all caged releases in Maryland, but only for the August release in Michigan. In Maryland, percent parasitism by S. agrili in August and September was higher than in October. The caging method described here should be useful in determining the climatic suitability of other regions before proceeding with large-scale releases of either species and may have utility in other wood-borer parasitoid systems as well.

Extending the electron spin coherence time of atomic hydrogen by dynamical decoupling.

PubMed

Mitrikas, George; Efthimiadou, Eleni K; Kordas, George

2014-02-14

We study the electron spin decoherence of encapsulated atomic hydrogen in octasilsesquioxane cages induced by the (1)H and (29)Si nuclear spin bath. By applying the Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence we significantly suppress the low-frequency noise due to nuclear spin flip-flops up to the point where a maximum T2 = 56 μs is observed. Moreover, dynamical decoupling with the CPMG sequence reveals the existence of two other sources of decoherence: first, a classical magnetic field noise imposed by the (1)H nuclear spins of the cage organic substituents, which can be described by a virtual fluctuating magnetic field with the proton Larmor frequency, and second, decoherence due to anisotropic hyperfine coupling between the electron and the inner (29)Si spins of the cage.

Experience-dependent plasticity in the mushroom bodies of the solitary bee Osmia lignaria (Megachilidae).

PubMed

Withers, Ginger S; Day, Nancy F; Talbot, Emily F; Dobson, Heidi E M; Wallace, Christopher S

2008-01-01

All members of the solitary bee species Osmia lignaria (the orchard bee) forage upon emergence from their natal nest cell. Conversely, in the honey bee, days-to-weeks of socially regulated behavioral development precede the onset of foraging. The social honey bee's behavioral transition to foraging is accompanied by neuroanatomical changes in the mushroom bodies, a region of the insect brain implicated in learning. If these changes were general adaptations to foraging, they should also occur in the solitary orchard bee. Using unbiased stereological methods, we estimated the volume of the major compartments of the mushroom bodies, the neuropil and Kenyon cell body region, in adult orchard bees. We compared the mushroom bodies of recently emerged bees with mature bees that had extensive foraging experience. To separate effects of general maturation from field foraging, some orchard bees were confined to a cage indoors. The mushroom body neuropil of experienced field foragers was significantly greater than that of both recently emerged and mature caged orchard bees, suggesting that, like the honey bee, this increase is driven by outdoor foraging experience. Unlike the honey bee, where increases in the ratio of neuropil to Kenyon cell region occur in the worker after emerging from the hive cell, the orchard bee emerged from the natal nest cell with a ratio that did not change with maturation and was comparable to honey-bee foragers. These results suggest that a common developmental endpoint may be reached via different development paths in social and solitary species of foraging bees.

Evaluation of Two Compressed Air Foam Systems for Culling Caged Layer Hens

PubMed Central

Weiher, Jaclyn A.; Alphin, Robert L.; Hougentogler, Daniel P.

2018-01-01

Simple Summary Control of avian influenza and similar diseases in commercial poultry operations is challenging; the six major steps are surveillance, biosecurity, quarantine, depopulation, disposal, and cleaning and disinfection. Depopulation is used to cull animals that are terminally ill and to reduce the number of animals that can spread an untreatable disease. Water-based foam depopulation was used effectively during the 2014–2015 highly pathogenic avian influenza outbreak in the United States. Water-based foam, however, cannot be used effectively in caged poultry operations. Compressed air foam systems were initially developed for structural fire-fighting and, with modifications, can provide the conditions required to effectively penetrate a poultry cage and provide sufficient residence time for depopulation. In this experiment, compressed air foam was used to depopulate caged layer hens. Compressed air foam resulted in faster unconsciousness than carbon dioxide gassing. The experiment demonstrated that compressed air foam systems have promise for depopulating birds raised in cages. Abstract Outbreaks of avian influenza (AI) and other highly contagious poultry diseases continue to be a concern for those involved in the poultry industry. In the situation of an outbreak, emergency depopulation of the birds involved is necessary. In this project, two compressed air foam systems (CAFS) were evaluated for mass emergency depopulation of layer hens in a manure belt equipped cage system. In both experiments, a randomized block design was used with multiple commercial layer hens treated with one of three randomly selected depopulation methods: CAFS, CAFS with CO2 gas, and CO2 gas. In Experiment 1, a Rowe manufactured CAFS was used, a selection of birds were instrumented, and the time to unconsciousness, brain death, altered terminal cardiac activity and motion cessation were recorded. CAFS with and without CO2 was faster to unconsciousness, however, the other parameters were not statistically significant. In Experiment 2, a custom Hale based CAFS was used to evaluate the impact of bird age, a selection of birds were instrumented, and the time to motion cessation was recorded. The difference in time to cessation of movement between pullets and spent hens using CAFS was not statistically significant. Both CAFS depopulate caged layers, however, there was no benefit to including CO2. PMID:29695072

Evaluation of cage micro-environment of mice housed on various types of bedding materials

USGS Publications Warehouse

Smith, E.; Stockwell, J.D.; Schweitzer, I.; Langley, S.H.; Smith, A.L.

2004-01-01

A variety of environmental factors can affect the outcomes of studies using laboratory rodents. One such factor is bedding. Several new bedding materials and processing methods have been introduced to the market in recent years, but there are few reports of their performance. In the studies reported here, we have assessed the cage micro-environment (in-cage ammonia levels, temperature, and humidity) of mice housed on various kinds of bedding and their combinations. We also compared results for bedding supplied as Nestpaks versus loose bedding. We studied C57BL/6J mice (commonly used) and NOD/LtJ mice (heavy soilers) that were maintained, except in one study, in static duplex cages. In general, we observed little effect of bedding type on in-cage temperature or humidity; however, there was considerable variation in ammonia concentrations. The lowest ammonia concentrations occurred in cages housing mice on hardwood bedding or a mixture of corncob and alpha cellulose. In one experiment comparing the micro-environments of NOD/LtJ male mice housed on woodpulp fiber bedding in static versus ventilated caging, we showed a statistically significant decrease in ammonia concentrations in ventilated cages. Therefore, our data show that bedding type affects the micro-environment in static cages and that effects may differ for ventilated cages, which are being used in vivaria with increasing frequency.

Enriched Open Field Facilitates Exercise and Social Interaction in 2 Strains of Guinea Pigs (Cavia porcellus)

PubMed Central

Brewer, Jacob S; Bellinger, Seanceray A; Joshi, Prianca; Kleven, Gale A

2014-01-01

Current housing guidelines for laboratory rodents include recommendations for enrichment. Working with guinea pigs, we have developed an open-field enrichment paradigm that provides several aspects of this species’ natural environment. These naturalistic aspects include access to increased space for exploration, access to western timothy (Phleum pratense L.) hay, and grouping as a herd to facilitate social interaction. To determine the immediate effect on behavior from access to the enriched environment, female guinea pigs from 2 strains, IAF Hairless and NIH Hartley, were observed in both standard home cages and an open-field enriched environment. Subjects were housed with cagemates in pairs for the home-cage observation and were grouped as a herd when in the open-field arena. Behaviors were videorecorded for 1 h and then scored. Salivary cortisol levels were measured both prior to and immediately after behavioral observations. Analyses revealed higher levels of activity and social interaction in the open-field arena compared with the home cage, with no significant change in salivary cortisol levels. These results suggest that exposure to the open-field environment provide increased opportunities for exercise and social enrichment. Although additional studies are needed to determine long-term effects on experimental outcomes, the open-field configuration holds promise as a laboratory enrichment paradigm for guinea pigs. PMID:25199089

Enriched open field facilitates exercise and social interaction in 2 strains of guinea pigs (Cavia porcellus).

PubMed

Brewer, Jacob S; Bellinger, Seanceray A; Joshi, Prianca; Kleven, Gale A

2014-07-01

Current housing guidelines for laboratory rodents include recommendations for enrichment. Working with guinea pigs, we have developed an open-field enrichment paradigm that provides several aspects of this species' natural environment. These naturalistic aspects include access to increased space for exploration, access to western timothy (Phleum pratense L.) hay, and grouping as a herd to facilitate social interaction. To determine the immediate effect on behavior from access to the enriched environment, female guinea pigs from 2 strains, IAF Hairless and NIH Hartley, were observed in both standard home cages and an open-field enriched environment. Subjects were housed with cagemates in pairs for the home-cage observation and were grouped as a herd when in the open-field arena. Behaviors were videorecorded for 1 h and then scored. Salivary cortisol levels were measured both prior to and immediately after behavioral observations. Analyses revealed higher levels of activity and social interaction in the open-field arena compared with the home cage, with no significant change in salivary cortisol levels. These results suggest that exposure to the open-field environment provide increased opportunities for exercise and social enrichment. Although additional studies are needed to determine long-term effects on experimental outcomes, the open-field configuration holds promise as a laboratory enrichment paradigm for guinea pigs.

Oxytocin reduces alcohol consumption in prairie voles.

PubMed

Stevenson, J R; Wenner, S M; Freestone, D M; Romaine, C C; Parian, M C; Christian, S M; Bohidar, A E; Ndem, J R; Vogel, I R; O'Kane, C M

2017-10-01

Alcohol use disorder (AUD) negatively affects millions of people every year in the United States, and effective treatments for AUD are still needed. The neuropeptide oxytocin has shown promise for reducing alcohol drinking in mice and rats. Because oxytocin also plays a key role in complex prosocial behaviors like bonding and attachment, we tested the effect of oxytocin on alcohol drinking in prairie voles, a species that both consumes high amounts of alcohol and forms oxytocin dependent social bonds in a manner similar to humans. Oxytocin treatment (1.0, 3.0, and 10.0mg/kg, i.p.) reduced alcohol consumption in male and female prairie voles in animals that had access to 15% ethanol vs water every other day for 12 alcohol drinking sessions. In animals with continuous access to 15% alcohol and water, oxytocin (3.0mg/kg) reduced alcohol consumption only in the first hour of access after treatment, with no significant effects on consumption over the 24-hr period. In an open field locomotor test, oxytocin (1.0, 3.0, and 10.0mg/kg, i.p.) did not affect overall locomotor activity; however, ethanol (2g/kg, i.p.) increased locomotor activity in males and females, and produced anxiolytic effects (increased time in the center of an open field) in females only. Because prairie voles have been shown to match the alcohol consumption of their cage mate, we evaluated the relationship between cage mates' alcohol drinking. There was an overall pattern of social facilitation (consumption by one cage mate predicted consumption by the other cage mate); however, we found significant individual differences across cages in which many cages did not show significant matching, and, in some cases one cage mate's consumption negatively predicted the other cage mate's consumption. Overall, our data provide support for the potential of oxytocin as a treatment to reduce alcohol consumption. Copyright © 2017 Elsevier Inc. All rights reserved.

Investigation of instability, dynamic forces, and effect of dynamic loading on strength of cages for the bearings in the high pressure oxygen turbopumps for the space shuttle main engine

NASA Technical Reports Server (NTRS)

Dufrane, K. F.; Kannel, J. W.; Merriman, T. L.; Rosenfield, A. R.

1985-01-01

Experiments were performed to determine the effect of cyclic loading on bearing cage strength. A long term working tensile load of approximately 1300 N (300 lbs) was found to be the likely maximum. Higher loads caused a decrease in cage tensile strength after the 125,000 cycle testing period. Poisson's ratio in compression was found to be highly dependent upon the direction of the fiberglass plies. At room temperature the value was 0.15 with the plies and 0.68 across the plies. At -196 C (-321 F), the value with the plies was 0.20. The results of the analyses conducted have again demonstrated the critical need for improved lubrication in the high pressure oxygen turbopump bearings. Lubricant films with low shear strength and low friction coefficients promote cage stability and decrease ball/cage forces during marginal operating conditions. The analysis of the effect of combined bearing loads on ball/cage loads has identified a radial load of 3600 N (800 lbs) as the maximum for the current clearance of the balls and cage pockets. Liquid oxygen impinging on the cage in the direction of rotation was found to enhance cage stability.

Improved Synthesis of Caged Glutamate and Caging Each Functional Group.

PubMed

Guruge, Charitha; Ouedraogo, Yannick P; Comitz, Richard L; Ma, Jingxuan; Losonczy, Attila; Nesnas, Nasri

2018-05-25

Glutamate is an excitatory neurotransmitter that controls numerous pathways in the brain. Neuroscientists make use of photoremovable protecting groups, also known as cages, to release glutamate with precise spatial and temporal control. Various cage designs have been developed and among the most effective has been the nitroindolinyl caging of glutamate. We, hereby, report an improved synthesis of one of the current leading molecules of caged glutamate, 4-carboxymethoxy-5,7-dinitroindolinyl glutamate (CDNI-Glu), which possesses efficiencies with the highest reported quantum yield of at least 0.5. We present the shortest route, to date, for the synthesis of CDNI-Glu in 4 steps, with a total reaction time of 40 h and an overall yield of 20%. We also caged glutamate at the other two functional groups, thereby, introducing two new cage designs: α-CDNI-Glu and N-CDNI-Glu. We included a study of their photocleavage properties using UV-vis, NMR, as well as a physiology experiment of a two-photon uncaging of CDNI-Glu in acute hippocampal brain slices. The newly introduced cage designs may have the potential to minimize the interference that CDNI-Glu has with the GABA A receptor. We are broadly disseminating this to enable neuroscientists to use these photoactivatable tools.

Study for elevator cage position during the braking period

NASA Astrophysics Data System (ADS)

Ungureanu, M.; Crăciun, I.; Bănică, M.; Dăscălescu, A.

2016-08-01

An important problem in order to study an elevator cage position for its braking period is to establish a correlation between the studies in the fields of mechanics and electric. The classical approaches to establish the elevator kinematic parameters are position, velocity and acceleration, but the last studies performed in order to determine the positioning performed by introducing supplementary another parameter - the jerk- which is derived with respect to time of acceleration. Thus we get a precise method for cage motion control for third-order trajectory planning.

A reappraisal of the role of mosquitoes in the transmission of myxomatosis in Britain.

PubMed

Service, M W

1971-03-01

Field experiments were made in southern England to re-examine the possibility that mosquitoes in Britain might feed on wild rabbits and hence be vectors of myxomatosis. Mosquitoes of several species were attracted to rabbits enclosed in cylindrical traps and in a trap in which the animal was placed in a wire mesh cage. Substantial numbers of mosquitoes were also caught biting, or attempting to bite, tethered rabbits which were not in cages or traps. Evidence that mosquitoes fed on wild rabbits under natural conditions was obtained from results of precipitin tests made on blood-smears collected from mosquitoes caught resting amongst vegetation. On a few evenings mosquitoes were seen to be attracted to healthy wild rabbits and apparently attempting to feed on them. Batches of two mosquito species collected from the field were infected with myxoma virus.It was concluded that contrary to previous beliefs mosquitoes in Britain feed to a certain extent on wild rabbits, and therefore are potential vectors of myxomatosis. No attempts were made to assess their relative importance in the transmission of the disease, which in Britain is transmitted mainly by the rabbit flea.

A reappraisal of the role of mosquitoes in the transmission of myxomatosis in Britain

PubMed Central

Service, M. W.

1971-01-01

Field experiments were made in southern England to re-examine the possibility that mosquitoes in Britain might feed on wild rabbits and hence be vectors of myxomatosis. Mosquitoes of several species were attracted to rabbits enclosed in cylindrical traps and in a trap in which the animal was placed in a wire mesh cage. Substantial numbers of mosquitoes were also caught biting, or attempting to bite, tethered rabbits which were not in cages or traps. Evidence that mosquitoes fed on wild rabbits under natural conditions was obtained from results of precipitin tests made on blood-smears collected from mosquitoes caught resting amongst vegetation. On a few evenings mosquitoes were seen to be attracted to healthy wild rabbits and apparently attempting to feed on them. Batches of two mosquito species collected from the field were infected with myxoma virus. It was concluded that contrary to previous beliefs mosquitoes in Britain feed to a certain extent on wild rabbits, and therefore are potential vectors of myxomatosis. No attempts were made to assess their relative importance in the transmission of the disease, which in Britain is transmitted mainly by the rabbit flea. ImagesPlate 1 PMID:4401995

Caged compounds for multichromic optical interrogation of neural systems

PubMed Central

Amatrudo, Joseph M.; Olson, Jeremy P.; Agarwal, Hitesh K.; Ellis-Davies, Graham C.R.

2014-01-01

Caged compounds have widely used by neurophysiologists to study many aspects of cellular signaling in glia and neurons. Biologically inert before irradiation, they can be loaded into cells via patch pipette or topically applied in situ to a defined concentration, photolysis releases the caged compound in a very rapid and spatially defined way. Since caged compounds are exogenous optical probes, they include not only natural products such neurotransmitters, calcium and IP3, but non-natural products such as fluorophores, drugs and antibodies. In this Technical Spotlight we provide a short introduction to the uncaging technique by discussing the nitroaromatic caging chromophores most widely used in such experiments (e.g. CNB1, DMNB, MNI and CDNI). We show that recently developed caging chromophores (RuBi and DEAC450) that are photolyzed with blue light (ca. 430–480 nm range) can be combined with traditional nitroaromatic caged compounds to enable two-color optical probing of neuronal function. For example, one-photon uncaging of either RuBi-GABA or DEAC450-GABA with a 473-nm laser is facile, and can block non-linear currents (dendritic spikes or action potentials) evoked by two-photon uncaging of CDNI-Glu at 720 nm. We also show that two-photon uncaging of DEAC450-Glu and CDNI-GABA at 900 and 720 nm, respectively, can be used to fire and block action potentials. Our experiments illustrate that recently developed chromophores have taken uncaging out of the “monochrome era”, in which it has existed since 1978, so as to enable multichromic interrogation of neuronal function with single synapse precision. PMID:25471355

Getting Out or Remaining in the Cage of Inauthentic Self: The Meaning of Existential Challenges in Patients' with Cancer

PubMed Central

Khoshnood, Zohreh; Iranmanesh, Sedigheh; Rayyani, Masoud; Dehghan, Mahlegha

2018-01-01

Context: Cancer as a life-threatening disease develops a range of existential challenges in persons. These challenges cause the patients to encounter some existential questions and tensions. This study method focuses on a person's experience about them. Aims: The aim of this study is to illuminate the meaning of existential challenges in patients with cancer in Iran. Subjects and Methods: A hermeneutic phenomenological approach, influenced by the philosophy of Ricoeur, was used to analyze the experiences of 10 Iranian patients with cancer. Data analysis was based on three stages of simple and fast understanding, structural analysis, and comprehensive understanding. Results: The present study showed that existential challenges in patients with cancer can be considered as getting out or remaining in the cage of inauthentic self. This theme consists of two subthemes “Being exposed to the light of awareness that revealed the cage of inauthentic self” and “The tension between getting out of the cage or remaining.” First, being exposed to the light of awareness revealed the cage of inauthentic self which subjectively refers to the emergence of existential questions, the past, the fear of future, and the collapse of physical body identity. Second, the tension between getting out of the cage or still staying which is characterized by anger, denial, sense of loneliness, and depression. Conclusions: According to the results of this qualitative study, it is possible to form discussion groups with peers or have self-reflective practice teaching groups to reflect patients' questions and existential challenges. In this way, participants can express themselves, share their experiences, challenges, learn, and find the answers. PMID:29736113

Exposure setup for animal experiments using a parabolic reflector.

PubMed

Schelkshorn, S; Tejero, S; Detlefsen, J

2007-01-01

The exposure setup presented is intended for a controlled, long-term and continuous exposition (20 Months, 24 h/day) of a large number of animals (100 rats at minimum) with standard GSM and UMTS signals, at 900 MHz and 1966 MHz, respectively. To obtain a homogeneous field within a large volume, the setup is based on the 'compact range' principle well known from antenna measurement facilities to produce a plane wave at relatively short ranges from the reflector. All requirements imposed due to the in vivo nature of the experiment, i.e. air-conditioning and easy access to the cages can be fulfilled.

Differential Response of a Local Population of Entomopathogenic Nematodes to Non-Native Herbivore Induced Plant Volatiles (HIPV) in the Laboratory and Field.

PubMed

Rivera, Monique J; Rodriguez-Saona, Cesar; Alborn, Hans T; Koppenhöfer, Albrecht M

2016-12-01

Recent work has shown the potential for enhanced efficacy of entomopathogenic nematodes (EPN) through their attraction to herbivore induced plant volatiles. However, there has been little investigation into the utilization of these attractants in systems other than in those in which they were identified. We compared (E)-β-caryophyllene and pregeijerene in the highbush blueberry (Vaccinium corymbosum) agroecosystem in their ability to enhance the attraction of EPN to and efficacy against the system's herbivore, oriental beetle (Anomala orientalis). The relative attractiveness of (E)-β-caryophyllene and pregeijerene to a local isolate of the EPN species Steinernema glaseri was tested in a six-arm olfactometer in the laboratory to gather baseline values of attraction to the chemicals alone in sand substrate before field tests. A similar arrangement was used in a V. corymbosum field by placing six cages with assigned treatments and insect larvae with and without compound into the soil around the base of 10 plants. The cages were removed after 72 h, and insect baits were retrieved and assessed for EPN infection. The lab results indicate that in sand alone (E)-β-caryophyllene is significantly more attractive than pregeijerene to the local S. glaseri isolate Conversely, there was no difference in attractiveness in the field study, but rather, native S. glaseri were more attracted to cages with G. mellonella larvae, no larvae, and cages with the blank control and G. mellonella larvae.

A wirelessly-powered homecage with animal behavior analysis and closed-loop power control.

PubMed

Yaoyao Jia; Zheyuan Wang; Canales, Daniel; Tinkler, Morgan; Chia-Chun Hsu; Madsen, Teresa E; Mirbozorgi, S Abdollah; Rainnie, Donald; Ghovanloo, Maysam

2016-08-01

This paper presents a new EnerCage-homecage system, EnerCage-HC2, for longitudinal electrophysiology data acquisition experiments on small freely moving animal subjects, such as rodents. EnerCage-HC2 is equipped with multi-coil wireless power transmission (WPT), closed-loop power control, bidirectional data communication via Bluetooth Low Energy (BLE), and Microsoft Kinect® based animal behavior tracking and analysis. The EnerCage-HC2 achieves a homogeneous power transfer efficiency (PTE) of 14% on average, with ~42 mW power delivered to the load (PDL) at a nominal height of 7 cm by the closed-loop power control mechanism. The Microsoft Kinect® behavioral analysis algorithm can not only track the animal position in real-time but also classify 5 different types of rodent behaviors: standstill, walking, grooming, rearing, and rotating. A proof-of-concept in vivo experiment was conducted on two awake freely behaving rats while successfully operating a one-channel stimulator and generating an ethogram.

Common variations in the pretest environment influence genotypic comparisons in models of anxiety.

PubMed

Izídio, G S; Lopes, D M; Spricigo, L; Ramos, A

2005-10-01

The behavioral characterization of rodent strains in different studies and laboratories can provide unreplicable results even when genotypes are kept constant and environmental control is maximized. In the present study, the influence of common laboratory environmental variables and their interaction with genotype on the results of behavioral tests of anxiety/emotionality were investigated. To this end, the inbred rat strains Lewis (LEW) and spontaneously hypertensive rats (SHR), which are known to differ for numerous emotionality-related behaviors, were tested in the open field (OF), elevated plus maze (EPM) and black/white box (BWB), while three environmental factors were systematically controlled and analyzed: (1) the experimenter handling the animal (familiar or unfamiliar); (2) the position of the home cage (top or bottom shelf of the rack) and (3) the behavioral state of the animal immediately before the test (arousal or rest). Experimenter familiarity did not alter the behavior of rats in the OF. Cage position, on the other hand, influenced the behavior in the OF and BWB, with rats housed in top cages appearing less anxious than those housed in the bottom. In the BWB (but not in the OF), these effects were genotype dependent. Finally, the behavioral state of the animals prior to testing altered the results of the EPM in a strain-dependent manner, with some anxiety-related genotypic differences being found only among rats that were aroused in their home cages. This study showed that common variations in the laboratory environment interact with genotype in behavioral tests of anxiety/emotionality. Recognizing and understanding such variations can help in the design of more effective experiments.

C60 as a Faraday cage

NASA Astrophysics Data System (ADS)

Delaney, P.; Greer, J. C.

2004-01-01

Endohedral fullerenes have been proposed for a number of technological uses, for example, as a nanoscale switch, memory bit and as qubits for quantum computation. For these technology applications, it is important to know the ease with which the endohedral atom can be manipulated using an applied electric field. We find that the Buckminsterfullerene (C60) acts effectively as a small Faraday cage, with only 25% of the field penetrating the interior of the molecule. Thus influencing the atom is difficult, but as a qubit the endohedral atom should be well shielded from environmental electrical noise. We also predict how the field penetration should increase with the fullerene radius.

Food consumption and food exchange of caged honey bees using a radioactive labelled sugar solution

PubMed Central

Libor, Anika; Kupelwieser, Vera; Crailsheim, Karl

2017-01-01

We measured the distribution of sugar solution within groups of caged honey bees (Apis mellifera) under standard in vitro laboratory conditions using 14C polyethylene glycol as a radioactive marker to analyze ingestion by individual bees after group feeding. We studied the impact of different experimental setups by varying the number of bees, age of bees, origin of bees, duration of experiment, the amount of available diet, and the influence of the neurotoxic pesticide imidacloprid in the diet on the feeding and food sharing behavior (trophallaxis). Sugar solution was non-uniformly distributed in bees in 36 out of 135 cages. As a measure of the extent to which the sugar diet was equally distributed between caged bees, we calculated the (inner 80%) intake ratio by dividing the intake of the 90th percentile bee by the intake of the 10th percentile bee. This intake ratio ranged from 1.3 to 94.8 in 133 individual cages, further supporting a non-uniform distribution of food among caged bees. We can expect a cage with 10 or 30 bees containing one bee that ingests, on average, the 8.8-fold of the bee in the same cage ingesting the smallest quantity of food. Inner 80% intake ratios were lower in experiments with a permanent or chronic offering of labelled sugar solution compared to temporary or acute feedings. After pooling the data of replicates to achieve a higher statistical power we compared different experimental setups. We found that uniform food distribution is best approached with 10 newly emerged bees per cage, which originate from a brood comb from a single colony. We also investigated the trophallaxis between caged honey bees which originally consumed the diet and newly added bees. Color marked bees were starved and added to the cages in a ratio of 10:5 or 20:20 after the initial set of bees consumed all the labelled sugar solution. The distribution of the labelled sugar solution by trophallaxis within 48 hours to added bees was 25% (10:5) or 45% (20:20) of the initial sugar solution. Imidacloprid at its median lethal dose (LD50) in the sugar solution reduced this post-feeding food transmission to 27% (20:20). Our results show that differences in food intake exist within caged bees that may lead to differential exposure that can influence the interpretation of toxicity tests. PMID:28355267

Food consumption and food exchange of caged honey bees using a radioactive labelled sugar solution.

PubMed

Brodschneider, Robert; Libor, Anika; Kupelwieser, Vera; Crailsheim, Karl

2017-01-01

We measured the distribution of sugar solution within groups of caged honey bees (Apis mellifera) under standard in vitro laboratory conditions using 14C polyethylene glycol as a radioactive marker to analyze ingestion by individual bees after group feeding. We studied the impact of different experimental setups by varying the number of bees, age of bees, origin of bees, duration of experiment, the amount of available diet, and the influence of the neurotoxic pesticide imidacloprid in the diet on the feeding and food sharing behavior (trophallaxis). Sugar solution was non-uniformly distributed in bees in 36 out of 135 cages. As a measure of the extent to which the sugar diet was equally distributed between caged bees, we calculated the (inner 80%) intake ratio by dividing the intake of the 90th percentile bee by the intake of the 10th percentile bee. This intake ratio ranged from 1.3 to 94.8 in 133 individual cages, further supporting a non-uniform distribution of food among caged bees. We can expect a cage with 10 or 30 bees containing one bee that ingests, on average, the 8.8-fold of the bee in the same cage ingesting the smallest quantity of food. Inner 80% intake ratios were lower in experiments with a permanent or chronic offering of labelled sugar solution compared to temporary or acute feedings. After pooling the data of replicates to achieve a higher statistical power we compared different experimental setups. We found that uniform food distribution is best approached with 10 newly emerged bees per cage, which originate from a brood comb from a single colony. We also investigated the trophallaxis between caged honey bees which originally consumed the diet and newly added bees. Color marked bees were starved and added to the cages in a ratio of 10:5 or 20:20 after the initial set of bees consumed all the labelled sugar solution. The distribution of the labelled sugar solution by trophallaxis within 48 hours to added bees was 25% (10:5) or 45% (20:20) of the initial sugar solution. Imidacloprid at its median lethal dose (LD50) in the sugar solution reduced this post-feeding food transmission to 27% (20:20). Our results show that differences in food intake exist within caged bees that may lead to differential exposure that can influence the interpretation of toxicity tests.

Validation of an automatic system (DoubleCage) for detecting the location of animals during preference tests.

PubMed

Tsai, P P; Nagelschmidt, N; Kirchner, J; Stelzer, H D; Hackbarth, H

2012-01-01

Preference tests have often been performed for collecting information about animals' acceptance of environmental refinement objects. In numerous published studies animals were individually tested during preference experiments, as it is difficult to observe group-housed animals with an automatic system. Thus, videotaping is still the most favoured method for observing preferences of socially-housed animals. To reduce the observation workload and to be able to carry out preference testing of socially-housed animals, an automatic recording system (DoubleCage) was developed for determining the location of group-housed animals in a preference test set-up. This system is able to distinguish the transition of individual animals between two cages and to record up to 16 animals at the same time (four animals per cage). The present study evaluated the reliability of the DoubleCage system. The data recorded by the DoubleCage program and the data obtained by human observation were compared. The measurements of the DoubleCage system and manual observation of the videotapes are comparable and significantly correlated (P < 0.0001) with good agreement. Using the DoubleCage system enables precise and reliable recording of the preferences of group-housed animals and a considerable reduction of animal observation time.

The effects of genetic manipulation, dieldrin treatment and irradiation on the mating competitiveness of male Anopheles arabiensis in field cages.

PubMed

Yamada, Hanano; Vreysen, Marc J B; Gilles, Jeremie R L; Munhenga, Givemore; Damiens, David D

2014-08-13

To enable the release of only sterile male Anopheles arabiensis mosquitoes for the sterile insect technique, the genetic background of a wild-type strain was modified to create a genetic sexing strain ANO IPCL1 that was based on a dieldrin resistance mutation. Secondly, the eggs of ANO IPCL1 require treatment with dieldrin to allow complete elimination of female L1 larvae from the production line. Finally, male mosquito pupae need to be treated with an irradiation dose of 75 Gy for sterilization. The effects of these treatments on the competitiveness of male An. arabiensis were studied. The competitiveness of ANO IPCL1 males that were treated either with irradiation or both dieldrin and irradiation, was compared with that of the wild-type strain (An. arabiensis Dongola) at a 1:1 ratio in 5.36 m3 semi-field cages located in a climate-controlled greenhouse. In addition, three irradiated: untreated male ratios were tested in semi-field cages (1:1, 5:1 and 10:1) and their competition for virgin wild-type females was assessed. The ANO IPCL1 males were equally competitive as the wild-type males in this semi-field setting. The ANO IPCL1 males irradiated at 75 Gy were approximately half as competitive as the unirradiated wild-type males. ANO IPCL1 males that had been treated with dieldrin as eggs, and irradiated with 75 Gy as pupae were slightly more competitive than males that were only irradiated. Ratios of 1:1, 5:1 and 10:1 irradiated ANO IPCL1 males: untreated wild-type males resulted in 31, 66 and 81% induced sterility in the female cage population, respectively. An irradiation dose of 75 Gy reduced the competitiveness of male ANO IPCL1 significantly and will need to be compensated by releasing higher numbers of sterile males in the field. However, the dieldrin treatment used to eliminate females appears to have an unexpected radioprotectant effect, however the mechanism is not understood. A sterile to wild-type ratio of 10:1 effectively reduced the population's fertility under the experimental field cage conditions, but further studies in the field will be needed to confirm the efficiency of sterile ANO IPCL1 males when competing against wild males for wild females.

Understanding gas capacity, guest selectivity, and diffusion in porous liquids† †Electronic supplementary information (ESI) available: Detailed synthetic procedures, experimental details and measurements (PDF). See DOI: 10.1039/c6sc05196k Click here for additional data file.

PubMed Central

Greenaway, Rebecca L.; Holden, Daniel; Eden, Edward G. B.; Stephenson, Andrew; Yong, Chin W.; Bennison, Michael J.; Hasell, Tom; Briggs, Michael E.; James, Stuart L.

2017-01-01

Porous liquids are a new class of material that could have applications in areas such as gas separation and homogeneous catalysis. Here we use a combination of measurement techniques, molecular simulations, and control experiments to advance the quantitative understanding of these liquids. In particular, we show that the cage cavities remain unoccupied in the absence of a suitable guest, and that the liquids can adsorb large quantities of gas, with gas occupancy in the cages as high as 72% and 74% for Xe and SF6, respectively. Gases can be reversibly loaded and released by using non-chemical triggers such as sonication, suggesting potential for gas separation schemes. Diffusion NMR experiments show that gases are in dynamic equilibrium between a bound and unbound state in the cage cavities, in agreement with recent simulations for related porous liquids. Comparison with gas adsorption in porous organic cage solids suggests that porous liquids have similar gas binding affinities, and that the physical properties of the cage molecule are translated into the liquid state. By contrast, some physical properties are different: for example, solid homochiral porous cages show enantioselectivity for chiral aromatic alcohols, whereas the equivalent homochiral porous liquids do not. This can be attributed to a loss of supramolecular organisation in the isotropic porous liquid. PMID:28553499

Caged compounds for multichromic optical interrogation of neural systems.

PubMed

Amatrudo, Joseph M; Olson, Jeremy P; Agarwal, Hitesh K; Ellis-Davies, Graham C R

2015-01-01

Caged compounds are widely used by neurophysiologists to study many aspects of cellular signaling in glia and neurons. Biologically inert before irradiation, they can be loaded into cells via patch pipette or topically applied in situ to a defined concentration; photolysis releases the caged compound in a very rapid and spatially defined way. As caged compounds are exogenous optical probes, they include not only natural products such neurotransmitters, calcium and IP3 but non-natural products such as fluorophores, drugs and antibodies. In this Technical Spotlight we provide a short introduction to the uncaging technique by discussing the nitroaromatic caging chromophores most widely used in such experiments [e.g. α-carboxy-ortho-nitrobenyl (CNB), dimethoxynitrobenzyl (DMNB), 4-methoxy-7-nitroindolinyl (MNI) and 4-carboxymethoxy-7-nitroindolinyl (CDNI)]. We show that recently developed caging chromophores [rutheniumbipyridial (RuBi) and 7-diethylaminocoumarin (DEAC)450] that are photolyzed with blue light (~ 430-480 nm range) can be combined with traditional nitroaromatic caged compounds to enable two-color optical probing of neuronal function. For example, one-photon uncaging of either RuBi-GABA or DEAC450-GABA with a 473-nm laser is facile, and can block nonlinear currents (dendritic spikes or action potentials) evoked by two-photon uncaging of CDNI-Glu at 720 nm. We also show that two-photon uncaging of DEAC450-Glu and CDNI-GABA at 900 and 720 nm, respectively, can be used to fire and block action potentials. Our experiments illustrate that recently developed chromophores have taken uncaging out of the 'monochrome era', in which it has existed since 1978, so as to enable multichromic interrogation of neuronal function with single-synapse precision. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Pathway-based Analysis of Fish Transcriptomics Data across Effluent Gradients in Minnesota Rivers

EPA Science Inventory

As part of a larger effort to assess the health of streams and rivers in Minnesota, a series of caged fish experiments were conducted in three locations: Ely, Hutchinson, and Rochester. The experimental design placed caged fish (fathead minnows, Pimephales promelas; FHM) across ...

Stress in cynomolgus monkeys (Macaca fascicularis) subjected to long-distance transport and simulated transport housing conditions.

PubMed

Fernström, A L; Sutian, W; Royo, F; Westlund, K; Nilsson, T; Carlsson, H-E; Paramastri, Y; Pamungkas, J; Sajuthi, D; Schapiro, S J; Hau, J

2008-11-01

The stress associated with transportation of non-human primates used in scientific research is an important but almost unexplored part of laboratory animal husbandry. The procedures and routines concerning transport are not only important for the animals' physical health but also for their mental health as well. The transport stress in cynomolgus monkeys (Macaca fascicularis) was studied in two experiments. In Experiment 1, 25 adult female cynomolgus monkeys were divided into five groups of five animals each that received different diets during the transport phase of the experiment. All animals were transported in conventional single animal transport cages with no visual or tactile contact with conspecifics. The animals were transported by lorry for 24 h at ambient temperatures ranging between 20 degrees C and 35 degrees C. Urine produced before, during and after transport was collected and analysed for cortisol by enzyme-linked immunosorbent assay (ELISA). All monkeys exhibited a significant increase in cortisol excretion per time unit during the transport and on the first day following transport.Although anecdotal reports concerning diet during transport, including the provision of fruits and/or a tranquiliser, was thought likely to influence stress responses, these were not corrobated by the present study. In Experiment 2, behavioural data were collected from 18 cynomolgus macaques before and after transfer from group cages to either single or pair housing, and also before and after a simulated transport, in which the animals were housed in transport cages. The single housed monkeys were confined to single transport cages and the pair housed monkeys were kept in their pairs in double size cages. Both pair housed and singly housed monkeys showed clear behavioural signs of stress soon after their transfer out of their group cages.However, stress-associated behaviours were more prevalent in singly housed animals than in pair housed animals, and these behaviours persisted for a longer time after the simulated transport housing event than in the pair housed monkeys. Our data confirm that the transport of cynomolgus monkeys is stressful and suggest that it would be beneficial for the cynomolgus monkeys to be housed and transported in compatible pairs from the time they leave their group cages at the source country breeding facility until they arrive at their final laboratory destination in the country of use.

Hyperactive behaviour in the mouse model of mucopolysaccharidosis IIIB in the open field and home cage environments.

PubMed

Langford-Smith, A; Malinowska, M; Langford-Smith, K J; Wegrzyn, G; Jones, S; Wynn, R; Wraith, J E; Wilkinson, F L; Bigger, B W

2011-08-01

Mucopolysaccharidosis IIIB (MPS IIIB) is a lysosomal storage disorder characterized by severe behavioural disturbances and progressive loss of cognitive and motor function. There is no effective treatment, but behavioural testing is a valuable tool to assess neurodegeneration and the effect of novel therapies in mouse models of disease. Several groups have evaluated behaviour in this model, but the data are inconsistent, often conflicting with patient natural history. We hypothesize that this discrepancy could be due to differences in open field habituation and home cage behaviour. Eight-month-old wild-type and MPS IIIB mice were tested in a 1-h open field test, performed 1.5 h after lights on, and a 24-h home cage behaviour test performed after 24 h of acclimatization. In the 1-h test, MPS IIIB mice were hyperactive, with increased rapid exploratory behaviour and reduced immobility time. No differences in anxiety were seen. Over the course of the test, differences became more pronounced with maximal effects at 1 h. The 24-hour home cage test was less reliable. There was evidence of increased hyperactivity in MPS IIIB mice, however, immobility was also increased, suggesting a level of inconsistency in this test. Performance of open field analysis within 1-2 h after lights on is probably critical to achieving maximal success as MPS IIIB mice have a peak in activity around this time. The open field test effectively identifies hyperactive behaviour in MPS IIIB mice and is a significant tool for evaluating effects of therapy on neurodegeneration. © 2011 The Authors. Genes, Brain and Behavior © 2011 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

Transition-Metal-Catalyzed Selective Cage B-H Functionalization of o-Carboranes.

PubMed

Quan, Yangjian; Qiu, Zaozao; Xie, Zuowei

2018-02-26

Carboranes are a class of carbon-boron molecular clusters with unusual thermal and chemical stabilities. They have been proved as very useful building blocks in supramolecular design, optoelectronics, nanomaterials, boron neutron capture therapy agents and organometallic/coordination chemistry. Thus, the functionalization of o-carboranes has received growing interests. Over the past decades, most of the works in this area have been focused on cage carbon functionalization as the weakly acidic cage C-H proton can be readily deprotonated by strong bases. In sharp contrast, selective cage B-H activation/functionalization among chemically very similar ten B-H vertices is very challenging. Considering the differences in electron density of ten cage B-H bonds in o-carborane and the nature of transition metal complexes, we have tackled this selectivity issue by means of organometallic chemistry. Our strategy is as follows: using electron-rich transition metal catalysts for the functionalization of the most electron-deficient B(3,6)-H vertices (bonded to both cage CH vertices); using electron-deficient transition-metal catalysts for the functionalization of relatively electron-rich B(8,9,10,12)-H vertices (with no bonding to both cage CH vertices); and using the combination of directing groups and electrophilic transition metal catalysts for the functionalization of B(4,5,7,11)-H vertices (bonded to only one cage CH vertex). Successful applications of such a strategy result in the preparation of a large variety of cage B-functionalized carboranes in a regioselective and catalytic manner, which are inaccessible by other means. It is believed that as this field progresses, other cage B-functionalized carboranes are expected to be synthesized, and the results detailed in this concept article will further these efforts. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

The effect of host relaxation and dynamics on guest molecule dynamics in H2/tetrahydrofuranhydrate.

PubMed

Peterson, Vanessa K; Shoko, Elvis; Kearley, Gordon J

2011-01-01

We use ab initio molecular dynamics simulations to obtain classically the effects of H2O cage motions on the potential-energy surface (PES) of encapsulated H2 in the H2/tetrahydrofuran-hydrate system. The significant differences between the PES for the H2 in rigid and flexible cages that we find will influence calculation of the quantum dynamics of the H2. Part of these differences arises from the relaxation of the H2O cage around the classical H2, with a second part arising from the coupling of both translational and rotational motions of H2 with the H20 cage. We find that isotopic substitution of 2H for 1H of the H2O cage affects the coupling, which has implications for experiments that require the use of 2H2O, including inelastic neutron scattering that uses 2H2O cages in order to focus on the H2 guest dynamics. Overall, this work emphasizes the importance of taking into account cage dynamics in any approach used to understand the dynamics of H2 guests in porous framework materials.

The effect of cage and house design on egg production and egg weight of White Leghorn hens: an epidemiological study.

PubMed

Garner, J P; Kiess, A S; Mench, J A; Newberry, R C; Hester, P Y

2012-07-01

Hen performance can be affected by many interacting variables related to cage design, such as floor area, height, tier arrangement, and feeder and drinker type and placement within the cage. Likewise, features of house design such as waste management and lighting can also affect hen productivity. The influence of these design aspects on hen performance has not been fully assessed. Determining the effects of numerous, interacting variables is impractical in a traditional experiment; therefore, an epidemiological approach, using variability in cage and house design among and within commercial producers, was employed to identify features that affect egg production and egg weight. A universal cage measurement system was created to calculate cage design variables. A database for recording information on cage design, resource location, waste management, environmental conditions, and hen productivity was developed. Production outcomes were assessed from placement to 60 wk of age in White Leghorns (n = 165-168 houses). Using GLM, a statistical model was identified that best described the variance in egg traits. Eggs/hen-housed increased with greater feeder space allocation (P = 0.031); taller cages (P = 0.029); rear (vs. front) drinker location in vertical cages (P = 0.026); and regular removal of manure from the house (P = 0.005). Case weight of eggs was greater in A-frame houses where manure was removed regularly instead of being left in the house (P < 0.001); with increasing cage floor slope (P = 0.001); in cages where drinkers were placed more toward the front or back of the cage as compared with the middle of the cage (P < 0.001); with more space/hen (P = 0.024); and with higher caloric intake (P < 0.001). Perhaps because of its negative correlation with egg production, case weight of eggs increased with less feeder space allocation (P = 0.004) and shorter cage heights (P < 0.001). These results reveal important effects of feeder space, floor space, cage height, drinker position, and waste management on hen productivity.

Mating competitiveness of sterile male Anopheles coluzzii in large cages.

PubMed

Maïga, Hamidou; Damiens, David; Niang, Abdoulaye; Sawadogo, Simon P; Fatherhaman, Omnia; Lees, Rosemary S; Roux, Olivier; Dabiré, Roch K; Ouédraogo, Georges A; Tripet, Fréderic; Diabaté, Abdoulaye; Gilles, Jeremie R L

2014-11-26

Understanding the factors that account for male mating competitiveness is critical to the development of the sterile insect technique (SIT). Here, the effects of partial sterilization with 90 Gy of radiation on sexual competitiveness of Anopheles coluzzii allowed to mate in different ratios of sterile to untreated males have been assessed. Moreover, competitiveness was compared between males allowed one versus two days of contact with females. Sterile and untreated males four to six days of age were released in large cages (~1.75 sq m) with females of similar age at the following ratios of sterile males: untreated males: untreated virgin females: 100:100:100, 300:100:100, 500:100:100 (three replicates of each) and left for two days. Competitiveness was determined by assessing the egg hatch rate and the insemination rate, determined by dissecting recaptured females. An additional experiment was conducted with a ratio of 500:100:100 and a mating period of either one or two days. Two controls of 0:100:100 (untreated control) and 100:0:100 (sterile control) were used in each experiment. When males and females consort for two days with different ratios, a significant difference in insemination rate was observed between ratio treatments. The competitiveness index (C) of sterile males compared to controls was 0.53. The number of days of exposure to mates significantly increased the insemination rate, as did the increased number of males present in the untreated: sterile male ratio treatments, but the number of days of exposure did not have any effect on the hatch rate. The comparability of the hatch rates between experiments suggest that An. coluzzii mating competitiveness experiments in large cages could be run for one instead of two days, shortening the required length of the experiment. Sterilized males were half as competitive as untreated males, but an effective release ratio of at least five sterile for one untreated male has the potential to impact the fertility of a wild female population. However, further trials in field conditions with wild males and females should be undertaken to estimate the ratio of sterile males to wild males required to produce an effect on wild populations.

Biology's built-in Faraday cages

NASA Astrophysics Data System (ADS)

Klee, Maurice M.

2014-05-01

Biological fluids are water-based, ionic conductors. As such, they have both high relative dielectric constants and substantial conductivities, meaning they are lossy dielectrics. These fluids contain charged molecules (free charges), whose movements play roles in essentially all cellular processes from metabolism to communication with other cells. Using the problem of a point source in air above a biological fluid of semi-infinite extent, the bound charges in the fluid are shown to perform the function of a fast-acting Faraday cage, which protects the interior of the fluid from external electric fields. Free charges replace bound charges in accordance with the fluid's relaxation time, thereby providing a smooth transition between the initial protection provided by the bound charges and the steady state protection provided by the free charges. The electric fields within the biological fluid are thus small for all times just as they would be inside a classical Faraday cage.

Infant titi monkey behavior in the open field test and the effect of early adversity

PubMed Central

Larke, Rebecca H.; Toubiana, Alice; Lindsay, Katrina A.; Mendoza, Sally P.; Bales, Karen L.

2017-01-01

The open field test is commonly used to measure anxiety-related behavior and exploration in rodents. Here, we used it as a standardized novel environment in which to evaluate the behavioral response of infant titi monkeys (Callicebus cupreus), to determine the effect of presence of individual family members, and to assess how adverse early experience alters infant behavior. Infants were tested in the open field for 5 days at ages 4 and 6 months in four successive 5 min trials on each day. A transport cage, which was situated on one side of the open field, was either empty (non-social control) or contained the father, mother, or sibling. Infant locomotor, vocalization, and exploratory behavior were quantified. Results indicated that age, sex, social condition, and early experience all had significant effects on infant behavior. Specifically, infants were generally more exploratory at 6 months and male infants were more exploratory than females. Infants distinguished between social and non-social conditions but made few behavioral distinctions between the attachment figure and other individuals. Infants which had adverse early life experience demonstrated greater emotional and physical independence, suggesting that early adversity led to resiliency in the novel environment. PMID:28605039

Between and within laboratory reliability of mouse behaviour recorded in home-cage and open-field.

PubMed

Robinson, Lianne; Spruijt, Berry; Riedel, Gernot

2018-04-15

Reproducibility of behavioural findings between laboratories is difficult due to behaviour being sensitive to environmental factors and interactions with genetics. The objective of this study was to investigate reproducibility of behavioural data between laboratories using the PhenoTyper home cage observation system and within laboratory reproducibility using different lighting regimes. The ambulatory activity of C57BL/6 and DBA/2 mice was tested in PhenoTypers in two laboratories under near identical housing and testing conditions (Exp. 1). Additionally activity and anxiety were also assessed in the open-field test. Furthermore, testing in either a normal or inverted light/dark cycle was used to determine effects of lighting regime in a within-laboratory comparison in Aberdeen (Exp. 2). Using the PhenoTyper similar circadian rhythms were observed across laboratories. Higher levels of baseline and novelty-induced activity were evident in Aberdeen compared to Utrecht although strain differences were consistent between laboratories. Open field activity was also similar across laboratories whereas strain differences in anxiety were different. Within laboratory analysis of different lighting regimes revealed that behaviour of the mice was sensitive to changes in lighting. Utilisation of a home cage observation system facilitates the reproducibility of activity but not anxiety-related behaviours across laboratories by eliminating environmental factors known to influence reproducibility in standard behavioural tests. Standardisation of housing/test conditions resulted in reproducibility of home cage and open field activity but not anxiety-related phenotypes across laboratories with some behaviours more sensitive to environmental factors. Environmental factors include lighting and time of day. Copyright © 2017 Elsevier B.V. All rights reserved.

Combining the Sterile Insect Technique with the Incompatible Insect Technique: III-Robust Mating Competitiveness of Irradiated Triple Wolbachia-Infected Aedes albopictus Males under Semi-Field Conditions.

PubMed

Zhang, Dongjing; Lees, Rosemary Susan; Xi, Zhiyong; Bourtzis, Kostas; Gilles, Jeremie R L

2016-01-01

Combination of the sterile insect technique with the incompatible insect technique is considered to be a safe approach to control Aedes albopictus populations in the absence of an accurate and scalable sex separation system or genetic sexing strain. Our previous study has shown that the triple Wolbachia-infected Ae. albopictus strain (wAlbA, wAlbB and wPip) was suitable for mass rearing and females could be completely sterilized as pupae with a radiation dose of at least 28 Gy. However, whether this radiation dose can influence the mating competitiveness of the triple infected males was still unknown. In this study we aimed to evaluate the effects of irradiation on the male mating competitiveness of the triple infected strain under laboratory and semi-field conditions. The results herein indicate that irradiation with a lower, female-sterilizing dose has no negative impact on the longevity of triple infected males while a reduced lifespan was observed in the wild type males (wAlbA and wAlbB) irradiated with a higher male-sterilizing dose, in small cages. At different sterile: fertile release ratios in small cages, triple-infected males induced 39.8, 81.6 and 87.8% sterility in a wild type female population at 1:1, 5:1 and 10:1 release ratios, respectively, relative to a fertile control population. Similarly, irradiated triple infected males induced 31.3, 70.5 and 89.3% sterility at 1:1, 5:1 and 10:1 release ratios, respectively, again relative to the fertile control. Under semi-field conditions at a 5:1 release ratio, relative to wild type males, the mean male mating competitiveness index of 28 Gy irradiated triple-infected males was significantly higher than 35 Gy irradiated wild type males, while triple infected males showed no difference in mean mating competitiveness to either irradiated triple-infected or irradiated wild type males. An unexpected difference was also observed in the relative male mating competitiveness of the triple infected strain after irradiation at 28 Gy dose in small vs large cages, with a higher male mating competitiveness index calculated from results of experiments in the large cages. Based on these results, we consider that the male mating performance of the triple infected strain after irradiation at 28 Gy, a dose required for complete female sterility and the avoidance of population replacement, is approximately equal to that of the wild type males under semi-field conditions. Though field evaluation is required, this suggests that the triple infected strain is suitable for irradiation and release as part of a combined SIT-IIT approach to Ae. albopictus control.

Combining the Sterile Insect Technique with the Incompatible Insect Technique: III-Robust Mating Competitiveness of Irradiated Triple Wolbachia-Infected Aedes albopictus Males under Semi-Field Conditions

PubMed Central

Zhang, Dongjing; Lees, Rosemary Susan; Xi, Zhiyong; Bourtzis, Kostas; Gilles, Jeremie R. L.

2016-01-01

Combination of the sterile insect technique with the incompatible insect technique is considered to be a safe approach to control Aedes albopictus populations in the absence of an accurate and scalable sex separation system or genetic sexing strain. Our previous study has shown that the triple Wolbachia-infected Ae. albopictus strain (wAlbA, wAlbB and wPip) was suitable for mass rearing and females could be completely sterilized as pupae with a radiation dose of at least 28 Gy. However, whether this radiation dose can influence the mating competitiveness of the triple infected males was still unknown. In this study we aimed to evaluate the effects of irradiation on the male mating competitiveness of the triple infected strain under laboratory and semi-field conditions. The results herein indicate that irradiation with a lower, female-sterilizing dose has no negative impact on the longevity of triple infected males while a reduced lifespan was observed in the wild type males (wAlbA and wAlbB) irradiated with a higher male-sterilizing dose, in small cages. At different sterile: fertile release ratios in small cages, triple-infected males induced 39.8, 81.6 and 87.8% sterility in a wild type female population at 1:1, 5:1 and 10:1 release ratios, respectively, relative to a fertile control population. Similarly, irradiated triple infected males induced 31.3, 70.5 and 89.3% sterility at 1:1, 5:1 and 10:1 release ratios, respectively, again relative to the fertile control. Under semi-field conditions at a 5:1 release ratio, relative to wild type males, the mean male mating competitiveness index of 28 Gy irradiated triple-infected males was significantly higher than 35 Gy irradiated wild type males, while triple infected males showed no difference in mean mating competitiveness to either irradiated triple-infected or irradiated wild type males. An unexpected difference was also observed in the relative male mating competitiveness of the triple infected strain after irradiation at 28 Gy dose in small vs large cages, with a higher male mating competitiveness index calculated from results of experiments in the large cages. Based on these results, we consider that the male mating performance of the triple infected strain after irradiation at 28 Gy, a dose required for complete female sterility and the avoidance of population replacement, is approximately equal to that of the wild type males under semi-field conditions. Though field evaluation is required, this suggests that the triple infected strain is suitable for irradiation and release as part of a combined SIT-IIT approach to Ae. albopictus control. PMID:26990981

Symmetric caging formation for convex polygonal object transportation by multiple mobile robots based on fuzzy sliding mode control.

PubMed

Dai, Yanyan; Kim, YoonGu; Wee, SungGil; Lee, DongHa; Lee, SukGyu

2016-01-01

In this paper, the problem of object caging and transporting is considered for multiple mobile robots. With the consideration of minimizing the number of robots and decreasing the rotation of the object, the proper points are calculated and assigned to the multiple mobile robots to allow them to form a symmetric caging formation. The caging formation guarantees that all of the Euclidean distances between any two adjacent robots are smaller than the minimal width of the polygonal object so that the object cannot escape. In order to avoid collision among robots, the parameter of the robots radius is utilized to design the caging formation, and the A⁎ algorithm is used so that mobile robots can move to the proper points. In order to avoid obstacles, the robots and the object are regarded as a rigid body to apply artificial potential field method. The fuzzy sliding mode control method is applied for tracking control of the nonholonomic mobile robots. Finally, the simulation and experimental results show that multiple mobile robots are able to cage and transport the polygonal object to the goal position, avoiding obstacles. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Analysis of SPAR 8 single-axis levitation experiment

NASA Technical Reports Server (NTRS)

Rush, J. E.; Schafer, C. F.; Holland, R. L.

1981-01-01

The melting and resolidification of SPAR 8 payload melting and resolidification of a glass specimen from the in a containerless condition and the retrieval and examination of the specimen from the. The absence of container contact was assured by use of a single-axis acoustic levitation system. However, the sample contacted a wire cage after being held without container contact by the acoustic field for only approximately 87 seconds. At this time, the sample was still molten and, therefore, flowed aroung the wire and continued to adhere to it. An analysis of why the sample did not remain levitated free of container contact is presented. The experiment is described, and experimental observations are discussed and analyzed.

Interactive effects of three pervasive marine stressors in a post-disturbance coral reef

NASA Astrophysics Data System (ADS)

Gil, Michael A.; Goldenberg, Silvan U.; Ly Thai Bach, Anne; Mills, Suzanne C.; Claudet, Joachim

2016-12-01

Ecosystems are commonly affected by natural, episodic disturbances that can abruptly and drastically alter communities. Although it has been shown that resilient ecosystems can eventually recover to pre-disturbed states, the extent to which communities in early stages of recovery could be affected by multiple anthropogenic stressors is poorly understood. Pervasive and rising anthropogenic stressors in coastal marine systems that could interactively affect the recovery of these systems following natural disturbances include high sedimentation, nutrient enrichment, and overfishing. Using a 6-month field experiment, we examined the effects of all combinations of these three stressors on key functional groups in the benthic community growing on simulated, post-disturbance reef patches within a system recovering from large-scale natural disturbances (corallivorous seastar outbreak and cyclone). Our study revealed that sedimentation, nutrient enrichment, and overfishing (simulated using exclusion cages) interactively affected coral survival and algal growth, with taxon-specific effects at multiple scales. First, our treatments affected corals and algae differently, with sedimentation being more detrimental to macroalgal growth but less detrimental to coral ( Porites rus) survival in caged plots, driving significant interactions between sedimentation and caging for both taxa. We also observed distinct responses between coral species and between algal functional groups, with the most extensive responses from algal turf biomass, for which sedimentation suppressed the synergistic (positive) combined effect of nutrient enrichment and caging. Our findings suggest that different combinations of ubiquitous anthropogenic stressors, related to either sea- or land-based activities, interactively influence community recovery from disturbance and may alter species compositions in the resulting community. Our findings further suggest that anthropogenic stressors could promote further degradation of coral reefs following natural disturbances by inhibiting recovery to coral-dominated states that provide vital ecosystem services to coastal populations worldwide.

Heat-shock protein 70 (Hsp70) as a biochemical stress indicator: an experimental field test in two congeneric intertidal gastropods (genus: Tegula).

PubMed

Tomanek, Lars; Sanford, Eric

2003-12-01

Although previous studies have demonstrated that heat-shock protein 70 (Hsp70) can be induced by environmental stress, little is known about natural variation in this response over short time scales. We examined how Hsp70 levels varied over days to weeks in two intertidal snail species of the genus Tegula: Sampling was conducted both under naturally changing environmental conditions and in different vertical zones on a rocky shore. The subtidal to low-intertidal T. brunnea was transplanted into shaded and unshaded mid-intertidal cages to assess temporal variation in Hsps under conditions of increased stress. For comparison, the low to mid-intertidal T. funebralis was transplanted into mid-intertidal cages, within this species' natural zone of occurrence. Snails were sampled every 3 to 4 days for one month, and endogenous levels of two Hsp70-kDa family members (Hsp72 and Hsp74) were quantified using solid-phase immunochemistry. Following periods of midday low tides, levels of Hsps increased greatly in transplanted T. brunnea but not in T. funebralis. Levels of Hsps increased less in T. brunnea transplanted to shaded cages than to unshaded cages, suggesting that prolonged emersion and reduction in feeding time per se are factors that are only mildly stressful. Upregulated levels of Hsps returned to base levels within days. In unmanipulated snails collected from their natural zones, Hsp levels showed little change with thermal variation, indicating that these species did not experience thermally stressful conditions during this study. However, under common conditions in the mid-intertidal zone, Hsp70 levels reflected the different thermal sensitivities of the physiological systems of these two species.

The water hexamer: three-body interactions, structures, energetics, and OH-stretch spectroscopy at finite temperature.

PubMed

Tainter, C J; Skinner, J L

2012-09-14

Using a newly developed and recently parameterized classical empirical simulation model for water that involves explicit three-body interactions, we determine the eleven most stable isomers of the water hexamer. We find that the lowest energy isomer is one of the cage structures, in agreement with far-IR and microwave experiments. The energy ordering for the binding energies is cage > glove > book > bag > chair > boat > chaise, and energies relative to the cage are in good agreement with CCSD(T) calculations. The three-body contributions to the cage, book, and chair are also in reasonable agreement with CCSD(T) results. The energy of each isomer results from a delicate balance involving the number of hydrogen bonds, the strain of these hydrogen bonds, and cooperative and anti-cooperative three-body interactions, whose contribution we can understand simply from the form of the three-body interactions in the simulation model. Oxygen-oxygen distances in the cage and book isomers are in good agreement with microwave experiments. Hydrogen-bond distances depend on both donor and acceptor, which can again be understood from the three-body model. Fully anharmonic OH-stretch spectra are calculated for these low-energy structures, and compared with shifted harmonic results from ab initio and density functional theory calculations. Replica-exchange molecular dynamics simulations were performed from 40 to 194 K, which show that the cage isomer has the lowest free energy from 0 to 70 K, and the book isomer has the lowest free energy from 70 to 194 K. OH-stretch spectra were calculated between 40 and 194 K, and results at 40, 63, and 79 K were compared to recent experiments, leading to re-assignment of the peaks in the experimental spectra. We calculate local OH-stretch cumulative spectral densities for different donor-acceptor types and compare to analogous results for liquid water.

Reef-based micropredators reduce the growth of post-settlement damselfish in captivity

NASA Astrophysics Data System (ADS)

Jones, C. M.; Grutter, A. S.

2008-09-01

Despite the ubiquity of micropredators and parasites on coral reefs, their effects on the survival and growth of juvenile fishes are virtually unstudied. Caging and laboratory experiments were used to investigate whether reef based micropredators fed on recently metamorphosed damselfish, the time of day that micropredation occurred, and whether micropredation affected fish growth and survival. Caged juveniles of the damselfish, Pomacentrus moluccensis, were held on the reef over four consecutive time periods. Micropredators (gnathiid and cirolanid isopods) were found associated with caged fish at night only, and cirolanids were observed attacking and killing some caged fish. In order to test the effect of micropredation on growth and survival without the influence of predatory fishes, groups of five P. moluccensis were caged for 2 weeks in one of three treatments: micropredators excluded, mesh control, or micropredators present. There were no significant differences in survival among the treatments, but fish were larger in cages with fewer survivors suggesting that competition for food was intense. Fish exposed to micropredators were larger than fish in the other two treatments, however, micropredator exclusion also excluded plankton; thus, differences in food availability among treatments during crepuscular periods likely confounded the treatment effect on fish growth. A laboratory growth experiment was performed to better control food availability and minimise handling stress, using a validated host-micropredator model. Individual juvenile damselfish, Dischistodus perspicillatus, were exposed to 0, 1 or 2 micropredators ( Gnathia falcipenis) each evening and fed equally for 8 days. Mortalities only occurred in fish exposed to micropredators on the first evening of the experiment, and fish exposed to two micropredators each evening were significantly smaller than unexposed fish. These results suggest that repeated gnathiid infections can reduce fish growth in the first week after settlement. Consequently, micropredation may affect the ecology of damselfish after settling on coral reefs.

Orientation in birds. The sun compass.

PubMed

Schmidt-Koenig, K; Ganzhorn, J U; Ranvaud, R

1991-01-01

The sun compass was discovered by G. Kramer in caged birds showing migratory restlessness. Subsequent experiments with caged birds employing directional training and clock shifts, carried out by Hoffman and Schmidt-Koenig, showed that the sun azimuth is used, and the sun altitude ignored. In the laboratory, McDonald found the accuracy to be +/- 3 degrees(-)+/- 5 degrees. According to Hoffmann and Schmidt-Koenig, caged birds trained at medium northern latitudes were able to allow for the sun's apparent movement north of the arctic circle, but not in equatorial and trans-equatorial latitudes. In homing experiments, and employing clock shifts, Schmidt-Koenig demonstrated that the sun compass is used by homing pigeons during initial orientation. This finding is the principal evidence for the existence of a map-and-compass navigational system. Pigeons living in equatorial latitudes utilize the sun compass even under the extreme solar conditions of equinox, achieving angular resolution of about 3 degrees in homing experiments. According to preliminary analyses, the homing pigeons' ephemerides are retarded by several weeks (Ranvaud, Schmidt-Koenig, Ganzhorn et al.).

The chemistry of cationic polyphosphorus cages – syntheses, structure and reactivity

PubMed Central

Holthausen, Michael H.

2014-01-01

The aim of this review is to provide a comprehensive view of the chemistry of cationic polyphosphorus cages. The synthetic protocols established for their preparation, which are all based on the functionalization of P4, and their intriguing follow-up chemistry are highlighted. In addition, this review intends to foster the interest of the inorganic, organic, catalytic and material oriented chemical communities in the versatile field of polyphosphorus cage compounds. In the long term, this is envisioned to contribute to the development of new synthetic procedures for the functionalization of P4 and its transformation into (organo-)phosphorus compounds and materials of added value. PMID:24740160

Protein cages and synthetic polymers: a fruitful symbiosis for drug delivery applications, bionanotechnology and materials science.

PubMed

Rother, Martin; Nussbaumer, Martin G; Renggli, Kasper; Bruns, Nico

2016-11-07

Protein cages are hollow protein nanoparticles, such as viral capsids, virus-like particles, ferritin, heat-shock proteins and chaperonins. They have well-defined capsule-like structures with a monodisperse size. Their protein subunits can be modified by genetic engineering at predetermined positions, allowing for example site-selective introduction of attachment points for functional groups, catalysts or targeting ligands on their outer surface, in their interior and between subunits. Therefore, protein cages have been extensively explored as functional entities in bionanotechnology, as drug-delivery or gene-delivery vehicles, as nanoreactors or as templates for the synthesis of organic and inorganic nanomaterials. The scope of functionalities and applications of protein cages can be significantly broadened if they are combined with synthetic polymers on their surface or within their interior. For example, PEGylation reduces the immunogenicity of protein cage-based delivery systems and active targeting ligands can be attached via polymer chains to favour their accumulation in diseased tissue. Polymers within protein cages offer the possibility of increasing the loading density of drug molecules, nucleic acids, magnetic resonance imaging contrast agents or catalysts. Moreover, the interaction of protein cages and polymers can be used to modulate the size and shape of some viral capsids to generate structures that do not occur with native viruses. Another possibility is to use the interior of polymer cages as a confined reaction space for polymerization reactions such as atom transfer radical polymerization or rhodium-catalysed polymerization of phenylacetylene. The protein nanoreactors facilitate a higher degree of control over polymer synthesis. This review will summarize the hybrid structures that have been synthesized by polymerizing from protein cage-bound initiators, by conjugating polymers to protein cages, by embedding protein cages into bulk polymeric materials, by forming two- and three-dimensional crystals of protein cages and dendrimers, by adsorbing proteins to the surface of materials, by layer-by-layer deposition of proteins and polyelectrolytes and by encapsulating polymers into protein cages. The application of these hybrid materials in the biomedical context or as tools and building blocks for bionanotechnology, biosensing, memory devices and the synthesis of materials will be highlighted. The review aims to showcase recent developments in this field and to suggest possible future directions and opportunities for the symbiosis of protein cages and polymers.

Dynamic free energy surfaces for sodium diffusion in type II silicon clathrates.

PubMed

Slingsby, J G; Rorrer, N A; Krishna, L; Toberer, E S; Koh, C A; Maupin, C M

2016-02-21

Earth abundant semiconducting type II Si clathrates have attracted attention as photovoltaic materials due to their wide band gaps. To realize the semiconducting properties of these materials, guest species that arise during the synthesis process must be completely evacuated from the host cage structure post synthesis. A common guest species utilized in the synthesis of Si clathrates is Na (metal), which templates the clathrate cage formation. Previous experimental investigations have identified that it is possible to evacuate Na from type II clathrates to an occupancy of less than 1 Na per unit cell. This work investigates the energetics, kinetics, and resulting mechanism of Na diffusion through type II Si clathrates by means of biased molecular dynamics and kinetic Monte Carlo simulations. Well-tempered metadynamics has been used to determine the potential of mean force for Na moving between clathrate cages, from which the thermodynamic preferences and transition barrier heights have been obtained. Kinetic Monte Carlo simulations based on the metadynamics results have identified the mechanism of Na diffusion in type II Si clathrates. The overall mechanism consists of a coupled diffusive process linked via electrostatic guest-guest interactions. The large occupied hexakaidechedral cages initially empty their Na guests to adjacent empty large cages, thereby changing the local electrostatic environment around the occupied small pentagonal dodecahedral cages and increasing the probability of Na guests to leave the small cages. This coupled process continues through the cross-over point that is identified as the point where large and small cages are equally occupied by Na guests. Further Na removal results in the majority of guests residing in the large cages as opposed to the small cages, in agreement with experiments, and ultimately a Na free structure.

The effects of a perch, dust bath, and nest box, either alone or in combination as used in furnished cages, on the welfare of laying hens.

PubMed

Barnett, J L; Tauson, R; Downing, J A; Janardhana, V; Lowenthal, J W; Butler, K L; Cronin, G M

2009-03-01

This experiment examined the welfare-related effects of individual furniture items alone or in combination in a factorial experiment using Hy-Line Brown hens housed in 8-bird furnished cages. Welfare was assessed during two 8-wk sampling periods commencing at 29 and 59 wk of age. Measurement of stress, immunology, feather, foot and claw condition, and behavior were taken, and bone strength was measured at the end of the experiment. With the exception of the positive effects of a perch on bone strength, any effects of furniture items were relatively small, even though the furniture was extensively used. Although there were changes in behavior and small changes in feather, foot, and claw condition, it is unclear whether these changes have any meaningful implications for welfare. In this experiment there were 2 additional external control treatments for a small study that examined the effects of increasing space per bird (8 birds in single- and double-width cages) and the effects of group size (8 and 16 birds in double-width cages); using similar methodologies, these treatments showed differences in egg corticosterone concentrations and evidence of immunosuppression. Together, these data suggest that although furniture when present was well-used, any effects of furniture on hen welfare measured by physical and physiological traits, other than the benefit of a perch on bone strength, were smaller than effects of group size and space allowance.

Interactive effects of nutrition, environment, and rat-strain on cortical and vertebral bone geometry and biomechanics

NASA Technical Reports Server (NTRS)

Zernicke, R. F.; Li, K.-C.; Salem, G. J.; Vailas, A. C.; Grindeland, R. E.

1990-01-01

An investigation was conducted to generate comparative data on the sensitivity of cortical- and vertebral-bone adaptations in two different rat strains maintained at conditions typical for spaceborne experiments conducted by U.S.A. and USSR. The effects of cage environment, diet, and rat-strain on the cortical (humerus) and vertebral (T7) bones of male Taconic-Sprague-Dawley and Czechoslovakian-Wistar rats were investigated using different flight-simulation cages (one rat/cage for U.S.A.; ten rats/cage for USSR conditions) and fed either U.S.A. or USSR diet. The results showed significant effects of these factors on the humeral and vertebral geometry and mechanical properties, as well as significant interactive effects on the mechanical properties of the humerus.

ASSESSING HABITAT QUALITY OF MOUNT HOPE BAY AND NARRAGANSETT BAY USING GROWTH, RNA:DNA, AND FEDDING HABITS OF CAGED JUVENILE WINTER FLOUNDER

EPA Science Inventory

Somatic growth rates, RNA:DNA, and feeding habits of juvenile Pseudopleuronectes americanus (Winter Flounder) were used to asses small-scale spatio-temporal variations in the habitat quality of Mount Hope Bay and Narragan-sett Bay, RI. Three successive caging experiments (14–16 d...

The Medium Is the Message: Pictures and Objects Evoke Distinct Conceptual Relations in Parent-Child Conversations

ERIC Educational Resources Information Center

Ware, Elizabeth A.; Gelman, Susan A.; Kleinberg, Felicia

2013-01-01

An important developmental task is learning to organize experience by forming conceptual relations among entities. (For example, a "lion" and a "snake" can be linked because both are animals; a lion and a cage can be linked because the "lion" lives in the "cage".) We propose that representational medium…

Photomodulating Gene Expression by Using Caged siRNAs with Single-Aptamer Modification.

PubMed

Zhang, Liangliang; Chen, Changmai; Fan, Xinli; Tang, Xinjing

2018-06-18

Caged siRNAs incorporating terminal modification were rationally designed for photochemical regulation of gene silencing induced by RNA interference (RNAi). Through the conjugation of a single oligonucleotide aptamer at the 5' terminus of the antisense RNA strand, enhancement of the blocking effect for RNA-induced silencing complex (RISC) formation/processing was expected, due both/either to the aptamers themselves and/or to their interaction with large binding proteins. Two oligonucleotide aptamers (AS1411 and MUC-1) were chosen for aptamer-siRNA conjugation through a photolabile linker. This caging strategy was successfully used to photoregulate gene expression both of firefly luciferase and of green fluorescent protein (GFP) in cells. Further patterning experiments revealed that spatial regulation of GFP expression was successfully achieved by using the aptamer-modified caged siRNA and light activation. We expect that further optimized caged siRNAs featuring aptamer conjugation will be promising for practical applications to spatiotemporal photoregulation of gene expression in the future. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Use of electric field sensors for recording respiration, heart rate, and stereotyped motor behaviors in the rodent home cage.

PubMed

Noble, Donald J; MacDowell, Camden J; McKinnon, Michael L; Neblett, Tamra I; Goolsby, William N; Hochman, Shawn

2017-02-01

Numerous environmental and genetic factors can contribute significantly to behavioral and cardiorespiratory variability observed experimentally. Affordable technologies that allow for noninvasive home cage capture of physio-behavioral variables should enhance understanding of inter-animal variability including after experimental interventions. We assessed whether EPIC electric field sensors (Plessey Semiconductors) embedded within or attached externally to a rodent's home cage could accurately record respiration, heart rate, and motor behaviors. Current systems for quantification of behavioral variables require expensive specialty equipment, while measures of respiratory and heart rate are often provided by surgically implanted or chronically affixed devices. Sensors accurately encoded imposed sinusoidal changes in electric field tested at frequencies ranging from 0.5-100Hz. Mini-metronome arm movements were easily detected, but response magnitude was highly distance dependent. Sensors accurately reported respiration during whole-body plethysmography. In anesthetized rodents, PVC tube-embedded sensors provided accurate mechanical detection of both respiratory and heart rate. Comparable success was seen in naturally behaving animals at rest or sleeping when sensors were attached externally. Video-verified motor behaviors (sniffing, grooming, chewing, and rearing) were detectable and largely separable by their characteristic voltage fluctuations. Larger movement-related events had comparably larger voltage dynamics that easily allowed for a broad approximation of overall motor activity. Spectrograms were used to quickly depict characteristic frequencies in long-lasting recordings, while filtering and thresholding software allowed for detection and quantification of movement-related physio-behavioral events. EPIC electric field sensors provide a means for affordable non-contact home cage detection of physio-behavioral variables. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of the effects of adrafinil, propentofylline, and nicergoline on behavior in aged dogs.

PubMed

Siwak, C T; Gruet, P; Woehrlé, F; Muggenburg, B A; Murphey, H L; Milgram, N W

2000-11-01

To compare the efficacy of adrafinil, propentofylline, and nicergoline for enhancing behavior of aged dogs. 36 Beagles between 9 and 16 years old. Dogs were randomly assigned to receive adrafinil (20 mg/kg of body weight, PO, q 24 h; n = 12), propentofylline (5 mg/kg, PO, q 12 h; 12), or nicergoline (0.5 mg/kg, PO, q 24 h; 12) for 33 days. Baseline behaviors in an open field and in kennels (home cage) were recorded before treatment. After treatment, behaviors in the open field were recorded 2 hours after drug administration on days 2, 15, and 28, and 10 hours after administration on days 7, 20, and 33. Behaviors in the home cage were recorded 2 and 7 hours after drug administration on days 4, 17, and 30. Treatment with adrafinil resulted in a significant increase in locomotion in each of the open-field tests and an increase in locomotion in the home cage. This latter increase was smaller and more variable than that in the open field. Locomotion was not affected by treatment with propentofylline or nicergoline. In the open field, sniffing decreased over time in all 3 groups, but the largest decline was observed in the propentofylline group. Treatment with adrafinil may improve the quality of life of aged dogs by increasing exploratory behavior and alertness.

Mercury cycling in agricultural and non-agricultural wetlands in the Yolo Bypass Wildlife Area, California: bioaccumulation in small fish

NASA Astrophysics Data System (ADS)

Ackerman, J. T.; Eagles-Smith, C. A.; Miles, K. A.; Ricca, M. A.

2007-12-01

We examined the bioaccumulation of mercury in small fish within white rice, wild rice, and permanent wetland habitats at the Yolo Wildlife Area during the 2007 rice growing season. We introduced 30 mosquito fish in each of four cages placed at the inlet, center, and outlet (two cages) of each wetland in June, immediately after the white rice fields were re-flooded after being seeded. All fish were removed from their cages 60-days after their introduction, with the exception that ten fish from each of the second cages at the outlets were removed 30-days after introduction to assess temporal trends in mercury exposure. Mercury concentrations will be compared between fish that were introduced into cages and reference fish that originated from the same fish stock (Sacramento County Vector Control). We also measured fish length and mass both when they were introduced and collected to 1) control for growth effects on mercury bioaccumulation and 2) examine whether wetland habitat influenced growth rates. Fish are currently being analyzed for mercury and results will be available by the conference.

Genotoxicity in native fish associated with agricultural runoff events

USGS Publications Warehouse

Whitehead, Andrew; Kuivila, Kathryn; Orlando, James L.; Kotelevtsev, S.; Anderson, Susan L.

2004-01-01

The primary objective of the present study was to test whether agricultural chemical runoff was associated with in-stream genotoxicity in native fish. Using Sacramento sucker (Catostomus occidentalis), we combined field-caging experiments in an agriculturally dominated watershed with controlled laboratory exposures to field-collected water samples, and we coupled genotoxicity biomarker measurements in fish with bacterial mutagenicity analysis of water samples. We selected DNA strand breakage as a genotoxicity biomarker and Ames Salmonella mutagenicity tests as a second, supporting indicator of genotoxicity. Data from experiments conducted during rainfall runoff events following winter application of pesticides in 2000 and 2001 indicated that DNA strand breaks were significantly elevated in fish exposed to San Joaquin River (CA, USA) water (38.8, 28.4, and 53.6% DNA strand breakage in year 2000 field, year 2000 lab, and year 2001 field exposures, respectively) compared with a nearby reference site (15.4, 8.7, and 12.6% DNA strand breakage in year 2000 field, year 2000 lab, and year 2001 field exposures, respectively). Time-course measurements in field experiments supported a linkage between induction of DNA strand breakage and the timing of agricultural runoff. San Joaquin River water also caused significant reversion mutation in two Ames Salmonella tester strains. Salmonella mutagenicity corroborated in-stream effects, further strengthening a causal relationship between runoff events and genotoxicity. Potentially responsible agents are discussed in the context of timing of runoff events in the field, concordance between laboratory and field exposures, pesticide application patterns in the drainage, and analytical chemistry data.

The Effect of Virus-Blocking Wolbachia on Male Competitiveness of the Dengue Vector Mosquito, Aedes aegypti

PubMed Central

Segoli, Michal; Hoffmann, Ary A.; Lloyd, Jane; Omodei, Gavin J.; Ritchie, Scott A.

2014-01-01

Background The bacterial endosymbiont Wolbachia blocks the transmission of dengue virus by its vector mosquito Aedes aegypti, and is currently being evaluated for control of dengue outbreaks. Wolbachia induces cytoplasmic incompatibility (CI) that results in the developmental failure of offspring in the cross between Wolbachia-infected males and uninfected females. This increases the relative success of infected females in the population, thereby enhancing the spread of the beneficial bacterium. However, Wolbachia spread via CI will only be feasible if infected males are sufficiently competitive in obtaining a mate under field conditions. We tested the effect of Wolbachia on the competitiveness of A. aegypti males under semi-field conditions. Methodology/Principal Findings In a series of experiments we exposed uninfected females to Wolbachia-infected and uninfected males simultaneously. We scored the competitiveness of infected males according to the proportion of females producing non-viable eggs due to incompatibility. We found that infected males were equally successful to uninfected males in securing a mate within experimental tents and semi-field cages. This was true for males infected by the benign wMel Wolbachia strain, but also for males infected by the virulent wMelPop (popcorn) strain. By manipulating male size we found that larger males had a higher success than smaller underfed males in the semi-field cages, regardless of their infection status. Conclusions/Significance The results indicate that Wolbachia infection does not reduce the competitiveness of A. aegypti males. Moreover, the body size effect suggests a potential advantage for lab-reared Wolbachia-males during a field release episode, due to their better nutrition and larger size. This may promote Wolbachia spread via CI in wild mosquito populations and underscores its potential use for disease control. PMID:25502564

The effect of virus-blocking Wolbachia on male competitiveness of the dengue vector mosquito, Aedes aegypti.

PubMed

Segoli, Michal; Hoffmann, Ary A; Lloyd, Jane; Omodei, Gavin J; Ritchie, Scott A

2014-12-01

The bacterial endosymbiont Wolbachia blocks the transmission of dengue virus by its vector mosquito Aedes aegypti, and is currently being evaluated for control of dengue outbreaks. Wolbachia induces cytoplasmic incompatibility (CI) that results in the developmental failure of offspring in the cross between Wolbachia-infected males and uninfected females. This increases the relative success of infected females in the population, thereby enhancing the spread of the beneficial bacterium. However, Wolbachia spread via CI will only be feasible if infected males are sufficiently competitive in obtaining a mate under field conditions. We tested the effect of Wolbachia on the competitiveness of A. aegypti males under semi-field conditions. In a series of experiments we exposed uninfected females to Wolbachia-infected and uninfected males simultaneously. We scored the competitiveness of infected males according to the proportion of females producing non-viable eggs due to incompatibility. We found that infected males were equally successful to uninfected males in securing a mate within experimental tents and semi-field cages. This was true for males infected by the benign wMel Wolbachia strain, but also for males infected by the virulent wMelPop (popcorn) strain. By manipulating male size we found that larger males had a higher success than smaller underfed males in the semi-field cages, regardless of their infection status. The results indicate that Wolbachia infection does not reduce the competitiveness of A. aegypti males. Moreover, the body size effect suggests a potential advantage for lab-reared Wolbachia-males during a field release episode, due to their better nutrition and larger size. This may promote Wolbachia spread via CI in wild mosquito populations and underscores its potential use for disease control.

Supramolecular control of the spin-dependent dynamics of long-lived charge-separated states at the micellar interface as studied by magnetic field effect.

PubMed

Miura, Tomoaki

2013-05-30

Spin selectivity in long-lived charge separation at the micellar interface is studied using the magnetic field effect (MFE). An amphiphilic viologen is complexed with a nonionic surfactant to form a supramolecular acceptor cage, of which the size is controlled by the acceptor concentration, as confirmed by dynamic light scattering measurement. Photoinduced electron transfer (ET) from a guest polyaromatic molecule to the viologen moiety is observed spin-dependently with time-resolved fluorescence (trFL) and transient absorption (TA). A negative MFE on the radical yield is successfully observed, which indicates generation of singlet-born long-lived radical pair that is realized by supramolecular control of the donor-acceptor (D-A) distances. The dominance of the singlet-precursor MFE is sensitive to the acceptor concentration, which presumably affects the D-A distance as well as the cage size. However, theoretical analysis of the MFE gives large recombination rates of ca. 10(8) s(-1), which indicate the contribution of spin-allowed recombination of the pseudocontact radical pair generated by still active in-cage diffusion. Dependence of the viologen concentration and alkyl chain length on the recombination and escape dynamics is discussed in terms of precursor spin states and the microenvironments in the cage.

EnerCage: A Smart Experimental Arena With Scalable Architecture for Behavioral Experiments

PubMed Central

Uei-Ming Jow; Peter McMenamin; Mehdi Kiani; Manns, Joseph R.; Ghovanloo, Maysam

2014-01-01

Wireless power, when coupled with miniaturized implantable electronics, has the potential to provide a solution to several challenges facing neuroscientists during basic and preclinical studies with freely behaving animals. The EnerCage system is one such solution as it allows for uninterrupted electrophysiology experiments over extended periods of time and vast experimental arenas, while eliminating the need for bulky battery payloads or tethering. It has a scalable array of overlapping planar spiral coils (PSCs) and three-axis magnetic sensors for focused wireless power transmission to devices on freely moving subjects. In this paper, we present the first fully functional EnerCage system, in which the number of PSC drivers and magnetic sensors was reduced to one-third of the number used in our previous design via multicoil coupling. The power transfer efficiency (PTE) has been improved to 5.6% at a 120 mm coupling distance and a 48.5 mm lateral misalignment (worst case) between the transmitter (Tx) array and receiver (Rx) coils. The new EnerCage system is equipped with an Ethernet backbone, further supporting its modular/scalable architecture, which, in turn, allows experimental arenas with arbitrary shapes and dimensions. A set of experiments on a freely behaving rat were conducted by continuously delivering 20 mW to the electronics in the animal headstage for more than one hour in a powered 3538 cm2 experimental area. PMID:23955695

EnerCage: a smart experimental arena with scalable architecture for behavioral experiments.

PubMed

Uei-Ming Jow; McMenamin, Peter; Kiani, Mehdi; Manns, Joseph R; Ghovanloo, Maysam

2014-01-01

Wireless power, when coupled with miniaturized implantable electronics, has the potential to provide a solution to several challenges facing neuroscientists during basic and preclinical studies with freely behaving animals. The EnerCage system is one such solution as it allows for uninterrupted electrophysiology experiments over extended periods of time and vast experimental arenas, while eliminating the need for bulky battery payloads or tethering. It has a scalable array of overlapping planar spiral coils (PSCs) and three-axis magnetic sensors for focused wireless power transmission to devices on freely moving subjects. In this paper, we present the first fully functional EnerCage system, in which the number of PSC drivers and magnetic sensors was reduced to one-third of the number used in our previous design via multicoil coupling. The power transfer efficiency (PTE) has been improved to 5.6% at a 120 mm coupling distance and a 48.5 mm lateral misalignment (worst case) between the transmitter (Tx) array and receiver (Rx) coils. The new EnerCage system is equipped with an Ethernet backbone, further supporting its modular/scalable architecture, which, in turn, allows experimental arenas with arbitrary shapes and dimensions. A set of experiments on a freely behaving rat were conducted by continuously delivering 20 mW to the electronics in the animal headstage for more than one hour in a powered 3538 cm(2) experimental area.

Separating the effects of shelter from additional cage enhancements for group-housed BALB/cJ mice.

PubMed

Swetter, Brentt J; Karpiak, Christie P; Cannon, J Timothy

2011-05-20

Enrichment studies with rodents have demonstrated that cage enhancements can improve animal welfare and performance on common behavioral measures, but few studies have compared more than one type of enrichment or controlled for confounds, and some have revealed undesirable effects including increased aggression. We compared effects on male (n=51) and female (n=52) BALB/cJ mice of three common additions to a standard home cage: shelter, shelter+running wheel, and shelter+novel objects. Mice in all conditions lived in standard sized cages with 3-4 mice per cage. Males evidenced significant condition effects. Shelter increased longevity and maintained low levels of aggression. Adding a running wheel increased aggression over shelter alone, changed behavior in the elevated plus (EP) and open field (OF), and maintained the improved longevity seen in all shelter conditions. Novel objects impacted behavioral measures compared to the standard condition. An Igloo shelter without running wheel creates a very different home cage environment than the same shelter with the running wheel attached. Shelter, with positive impact on animal welfare, minimal effects on some common behavioral measures, and some positive effects on test variance, warrants consideration for routine inclusion with group-housed BALB/cJ males. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Molecular Static Third-Order Polarizabilities of Carbon-Cage Fullerenes and their Correlation with Three Geometric Parameters: Group Order, Aromaticity, and Size

NASA Technical Reports Server (NTRS)

Moore, Craig E.; Cardelino, Beatriz H.; Frazier, Donald O.; Niles, Julian; Wang, Xian-Qiang

1997-01-01

Calculations were performed on the valence contribution to the static molecular third-order polarizabilities (gamma) of thirty carbon-cage fullerenes (C60, C70, five isomers of C78, and twenty-three isomers of C84). The molecular structures were obtained from B3LYP/STO-3G calculations. The values of the tensor elements and an associated numerical uncertainty were obtained using the finite-field approach and polynomial expansions of orders four to eighteen of polarization versus static electric field data. The latter information was obtained from semiempirical calculations using the AM1 hamiltonian.

Genotoxic Potential of 1.6 GHz Wireless Communication Signal: In vivo Two-Year Bioassay

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

Vijayalaxmi, Vijay; Sasser, Lyle B.; Morris, J E.

Timed-pregnant Fischer 344 rats (from nineteenth day of gestation) and their nursing offspring (until weaning) were exposed to a far-field 1.6 GHz Iridium wireless communication signal for 2 h/day, 5 days/week. Far-field whole-body exposures were conducted with a field intensity of 0.43 mW/cm 2 and whole-body average specific absorption rate (SAR) of 0.036 to 0.077 W/kg (0.10 to 0.22 W/kg in the brain). This was followed by chronic, head-only exposures of male and female offspring to a near-field 1.6 GHz signal for 2 h/day, 5 days/week, over 2 years. Near-field exposures were conducted at an SAR of 0.16 or 1.6more » W/kg in the brain. Concurrent sham-exposed and cage control rats were also included in the study. At the end of 2 years, all rats were necropsied. Bone marrow smears were examined for the extent of genotoxicity, assessed from the presence of micronuclei in polychromatic erythrocytes. The results indicated that the incidence of micronuclei/ 2000 polychromatic erythrocytes were not significantly different between 1.6 GHz-exposed, sham-exposed and cage control rats. The group mean frequencies were 5.6 6 1.8 (130 rats exposed to 1.6 GHz at 0.16 W/kg SAR), 5.4 6 1.5 (135 rats exposed to 1.6 GHz at 1.6 W/kg SAR), 5.6 6 1.7 (119 sham-exposed rats), and 5.8 6 1.8 (100 cage control rats). In contrast, positive control rats treated with mitomycin C exhibited significantly elevated incidence of micronuclei/2000 polychromatic erythrocytes in bone marrow cells; the mean frequency was 38.2 6 7.0 (five rats). Thus there was no evidence for excess genotoxicity in rats that were chronically exposed to 1.6 GHz compared to sham-exposed and cage controls.« less

Anterior debridement and fusion followed by posterior pedicle screw fixation in pyogenic spondylodiscitis: autologous iliac bone strut versus cage.

PubMed

Pee, Yong Hun; Park, Jong Dae; Choi, Young-Geun; Lee, Sang-Ho

2008-05-01

An anterior approach for debridement and fusion with autologous bone graft has been recommended as the gold standard for surgical treatment of pyogenic spondylodiscitis. The use of anterior foreign body implants at the site of active infection is still a challenging procedure for spine surgeons. Several authors have recently introduced anterior grafting with titanium mesh cages instead of autologous bone strut in the treatment of spondylodiscitis. The authors present their experience of anterior fusion with 3 types of cages followed by posterior pedicle screw fixation. They also compare their results with the use of autologous iliac bone strut. The authors retrospectively reviewed the cases of 60 patients with pyogenic spondylodiscitis treated by anterior debridement between January 2003 and April 2005. Fusion using either cages or iliac bone struts was performed during the same course of anesthesia followed by posterior fixation. Twenty-three patients underwent fusion with autologous iliac bone strut, and 37 patients underwent fusion with 1 of the 3 types of cages. The infections resolved in all patients, as noted by normalization of their erythrocyte sedimentation rates and C-reactive protein levels. Patients in both groups were evaluated in terms of their preoperative and postoperative clinical and imaging findings. Single-stage anterior debridement and cage fusion followed by posterior pedicle screw fixation can be effective in the treatment of pyogenic spondylodiscitis. There was no difference in clinical and imaging outcomes between the strut group and cage group except for the subsidence rate. The subsidence rate was higher in the strut group than in the cage group. The duration until subsidence was also shorter in the strut group than in the cage group.

Infant titi monkey behavior in the open field test and the effect of early adversity.

PubMed

Larke, Rebecca H; Toubiana, Alice; Lindsay, Katrina A; Mendoza, Sally P; Bales, Karen L

2017-09-01

The open field test is commonly used to measure anxiety-related behavior and exploration in rodents. Here, we used it as a standardized novel environment in which to evaluate the behavioral response of infant titi monkeys (Callicebus cupreus), to determine the effect of presence of individual family members, and to assess how adverse early experience alters infant behavior. Infants were tested in the open field for 5 days at ages 4 and 6 months in four successive 5 min trials on each day. A transport cage, which was situated on one side of the open field, was either empty (non-social control) or contained the father, mother, or sibling. Infant locomotor, vocalization, and exploratory behavior were quantified. Results indicated that age, sex, social condition, and early experience all had significant effects on infant behavior. Specifically, infants were generally more exploratory at 6 months and male infants were more exploratory than females. Infants distinguished between social and non-social conditions but made few behavioral distinctions between the attachment figure and other individuals. Infants which had adverse early life experience demonstrated greater emotional and physical independence, suggesting that early adversity led to resiliency in the novel environment. © 2017 Wiley Periodicals, Inc.

Microelectronic bioinstrumentation systems

NASA Technical Reports Server (NTRS)

Ko, W. H.; Hynecek, J.

1975-01-01

The possibility of using RF fields to power biologically implanted transmitters used in biomedical experiments was investigated. This approach would be especially useful when animal subjects are strapped in chairs or confined in cages. A telemetry system using an external source of energy has the additional advantage of not being limited in operation by battery lifetime and can therefore operate for virtually infinite lengths of time. A description of a system based on this principle is given. Progress in the development of battery-driven transmitters is also reported, including an ingestible temperature telemetry system and a resistance-to-pulse frequency convertor for implantable temperature telemetry systems.

Reciprocal activation/inactivation of ERK in the amygdala and frontal cortex is correlated with the degree of novelty of an open-field environment.

PubMed

Sanguedo, Frederico Velasco; Dias, Caio Vitor Bueno; Dias, Flavia Regina Cruz; Samuels, Richard Ian; Carey, Robert J; Carrera, Marinete Pinheiro

2016-03-01

Phosphorylated extracellular signal-regulated kinase (ERK) has been used to identify brain areas activated by exogenous stimuli including psychostimulant drugs. Assess the role of the amygdala in emotional responses. Experimental manipulations were performed in which environmental familiarity was the variable. To provide the maximal degree of familiarity, ERK was measured after removal from the home cage and re-placement back into the same cage. To maximize exposure to an unfamiliar environment, ERK was measured following placement into a novel open field. To assess whether familiarity was the critical variable in the ERK response to the novel open field, ERK was also measured after either four or eight placements into the same environment. ERK quantification was carried out in the amygdala, frontal cortex, and the nucleus accumbens. After home cage re-placement, ERK activation was found in the frontal cortex and nucleus accumbens but was absent in the amygdala. Following placement in a novel environment, ERK activation was more prominent in the amygdala than the frontal cortex or nucleus accumbens. In contrast, with habituation to the novel environment, ERK phosphors declined markedly in the amygdala but increased in the frontal cortex and nucleus accumbens to the level observed following home cage re-placement. The differential responsiveness of the amygdala versus the frontal cortex and the nucleus accumbens to a novel versus a habituated environment is consistent with a reciprocal interaction between these neural systems and points to their important role in the mediation of behavioral activation to novelty and behavioral inactivation with habituation.

Energy landscape paving simulations of the trp-cage protein.

PubMed

Schug, Alexander; Wenzel, Wolfgang; Hansmann, Ulrich H E

2005-05-15

We evaluate the efficiency of multiple variants of energy landscape paving in all-atom simulations of the trp-cage protein using a recently developed new force field. Especially, we introduce a temperature-free variant of the method and demonstrate that it allows a fast scanning of the energy landscape. Nativelike structures are found in less time than by other techniques. The sampled low-energy configurations indicate a funnel-like energy landscape.

Radio frequency magnetic field effects on molecular dynamics and iron uptake in cage proteins.

PubMed

Céspedes, Oscar; Inomoto, Osamu; Kai, Shoichi; Nibu, Yoshinori; Yamaguchi, Toshio; Sakamoto, Nobuyoshi; Akune, Tadahiro; Inoue, Masayoshi; Kiss, Takanobu; Ueno, Shoogo

2010-05-01

The protein ferritin has a natural ferrihydrite nanoparticle that is superparamagnetic at room temperature. For native horse spleen ferritin, we measure the low field magnetic susceptibility of the nanoparticle as 2.2 x 10(-6) m(3) kg(-1) and its Néel relaxation time at about 10(-10) s. Superparamagnetic nanoparticles increase their internal energy when exposed to radio frequency magnetic fields due to the lag between magnetization and applied field. The energy is dissipated to the surrounding peptidic cage, altering the molecular dynamics and functioning of the protein. This leads to an increased population of low energy vibrational states under a magnetic field of 30 microT at 1 MHz, as measured via Raman spectroscopy. After 2 h of exposure, the proteins have a reduced iron intake rate of about 20%. Our results open a new path for the study of non-thermal bioeffects of radio frequency magnetic fields at the molecular scale.

[Experiment with rats on a 22-day flight on the "Kosmos-605" biological satellite (objectives and methods)].

PubMed

Il'in, E A; Serova, L V; Noskin, A D

1976-01-01

In 1974 a rat experiment was carried out onboard the Cosmos-605 biosatellite. Inflight Wistar rats were kept unrestrained in small cages. The cages were equipped with a feeder, water supply, light source and a ventilation device. The state of the animals was assessed with respect to their motor activity. The flight experiment was preceded by a number of preparatory runs and testinns that were completed with an end-to-end experiment in a biosatellite mockup. The flight experiment was paralleled by the ground-based synchroneous experiment which simulated almost entirely the flight profile. For each experiment rats were selected and trained during a month's observation. Postflight rats were exposed to clinical, physiological, morphological, cytochemical and biochemical investigations. Tissue examinations were performed on the 2nd-3rd day (20 rats) and 26-27th day (12 rats) after flight. Four rats were kept to study remote aftereffects.

Direction sensitive neutron detector

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

Ahlen, Steven; Fisher, Peter; Dujmic, Denis

2017-01-31

A neutron detector includes a pressure vessel, an electrically conductive field cage assembly within the pressure vessel and an imaging subsystem. A pressurized gas mixture of CF.sub.4, .sup.3He and .sup.4He at respective partial pressures is used. The field cage establishes a relatively large drift region of low field strength, in which ionization electrons generated by neutron-He interactions are directed toward a substantially smaller amplification region of substantially higher field strength in which the ionization electrons undergo avalanche multiplication resulting in scintillation of the CF.sub.4 along scintillation tracks. The imaging system generates two-dimensional images of the scintillation patterns and employs track-findingmore » to identify tracks and deduce the rate and direction of incident neutrons. One or more photo-multiplier tubes record the time-profile of the scintillation tracks permitting the determination of the third coordinate.« less

SYSTEMS FOR EXPOSING MICE TO 2,450-MHZ ELECTROMAGNETIC FIELDS

EPA Science Inventory

Two systems for exposing mice to 2,450-MHz electromagnetic fields are described. In a waveguide system, four mice were placed in a Styrofoam cage and exposed dorsally to circularly polarized electromagnetic fields. The temperature and humidity in the mouse holder were kept consta...

Comparative study of two approaches to model the offshore fish cages

NASA Astrophysics Data System (ADS)

Zhao, Yun-peng; Wang, Xin-xin; Decew, Jud; Tsukrov, Igor; Bai, Xiao-dong; Bi, Chun-wei

2015-06-01

The goal of this paper is to provide a comparative analysis of two commonly used approaches to discretize offshore fish cages: the lumped-mass approach and the finite element technique. Two case studies are chosen to compare predictions of the LMA (lumped-mass approach) and FEA (finite element analysis) based numerical modeling techniques. In both case studies, we consider several loading conditions consisting of different uniform currents and monochromatic waves. We investigate motion of the cage, its deformation, and the resultant tension in the mooring lines. Both model predictions are sufficient close to the experimental data, but for the first experiment, the DUT-FlexSim predictions are slightly more accurate than the ones provided by Aqua-FE™. According to the comparisons, both models can be successfully utilized to the design and analysis of the offshore fish cages provided that an appropriate safety factor is chosen.

The Usage of Geographical Information System in the Selection of Floating Cages Location for Aquaculture at Prigi Bay, Trenggalek Regency, East Java

NASA Astrophysics Data System (ADS)

Armono, H. D.; Mahaputra, B. G.; Zikra, M.

2018-03-01

Floating cages is one of the methods of fish farming (aqua culture) that can be developed at rivers, lakes or seas. To determine a proper location for floating cages, there are some requirements that need to be fulfilled to maintain sustainibility of floating cages. Those requirements are the quality of the environment. This paper will discuss the selection of best location for aquaculture activities using Weighted Overlay method in the Geographical Information System, based on the the concentration of chlorophyll-a, sea surface temperature presented by Aqua MODIS Level 1b satellite images. The satellite data will be associated with the measured field data on March and October 2016. The study take place on Prigi Bay, at Trenggalek Regency, East Java. Based on spatial analysis in the Geographical Information System, the Prigi bay generally suitable for aquaculture activities using floating net cages. The result of Weighted Overlay combinations in both periods showed a mean score of 2.18 of 3 where 8.33 km2 (23.13% of the water area) considered as "very suitable" and 27.67 km2 (76.87% of water area) considered "suitable".

Numerical and experimental investigation of strip deformation in cage roll forming process for pipes with low ratio of thickness/diameter

NASA Astrophysics Data System (ADS)

Kasaei, M. M.; Naeini, H. Moslemi; Tehrani, M. Salmani; Tafti, R. Azizi

2011-01-01

Cage roll forming is one of the advanced methods of cold roll forming process which is used widely for producing ERW pipes. In addition to decreasing the production cost and time, using cage roll forming provides smooth deformation on the strip. Few studies can be found about cage roll forming because of its complexity, and the available knowledge is experience-based more than science-based. In this paper, deformation of pipes with low ratio of thickness/diameter is investigated by 3D finite element simulation in Marc-Mentat software. Edge buckling defect in cage roll forming of low ratio of thickness/diameter pipes is very important. Due to direct influence of longitudinal strain on the edge buckling phenomenon, longitudinal strains at the edge and center line of the strip are investigated and high risk stands are introduced. The deformed strip is predicted using the simulation results and effects of each cage forming stage on the deformed strip profile are specified. In order to verify the simulation results, strip width and opening distance of the two edges in different forming stages are obtained from the simulations and compared with the experimental data which were measured from the production line. A good agreement between the experimental and simulated results is observed.

Fragmentation of endohedral fullerene H o 3 N @ C 80 in an intense femtosecond near-infrared laser field

DOE PAGES

Xiong, Hui; Fang, Li; Osipov, Timur; ...

2018-02-22

The fragmentation of gas phase endohedral fullerene, Ho 3N@C 80, was investigated using femtosecond near-infrared laser pulses with an ion velocity map imaging spectrometer. Here, we observed that Ho + abundance associated with carbon cage opening dominates at an intensity of 1.1 x 10 14 W/cm 2. As the intensity increases, the Ho + yield associated with multifragmentation of the carbon cage exceeds the prominence of Ho + associated with the gentler carbon cage opening. Moreover, the power law dependence of Ho + on laser intensity indicates that the transition of the most likely fragmentation mechanisms occurs around 2.0 xmore » 10 14 W/cn 2.« less

Fragmentation of endohedral fullerene H o 3 N @ C 80 in an intense femtosecond near-infrared laser field

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

Xiong, Hui; Fang, Li; Osipov, Timur

The fragmentation of gas phase endohedral fullerene, Ho 3N@C 80, was investigated using femtosecond near-infrared laser pulses with an ion velocity map imaging spectrometer. Here, we observed that Ho + abundance associated with carbon cage opening dominates at an intensity of 1.1 x 10 14 W/cm 2. As the intensity increases, the Ho + yield associated with multifragmentation of the carbon cage exceeds the prominence of Ho + associated with the gentler carbon cage opening. Moreover, the power law dependence of Ho + on laser intensity indicates that the transition of the most likely fragmentation mechanisms occurs around 2.0 xmore » 10 14 W/cn 2.« less

A Smart Wirelessly Powered Homecage for Long-Term High-Throughput Behavioral Experiments

PubMed Central

Lee, Byunghun; Kiani, Mehdi

2015-01-01

A wirelessly powered homecage system, called the EnerCage-HC, that is equipped with multicoil wireless power transfer, closed-loop power control, optical behavioral tracking, and a graphic user interface is presented for longitudinal electrophysiology and behavioral neuroscience experiments. The EnerCage-HC system can wirelessly power a mobile unit attached to a small animal subject and also track its behavior in real-time as it is housed inside a standard homecage. The EnerCage-HC system is equipped with one central and four overlapping slanted wire-wound coils with optimal geometries to form three- and four-coil power transmission links while operating at 13.56 MHz. Utilizing multicoil links increases the power transfer efficiency (PTE) compared with conventional two-coil links and also reduces the number of power amplifiers to only one, which significantly reduces the system complexity, cost, and heat dissipation. A Microsoft Kinect installed 90 cm above the homecage localizes the animal position and orientation with 1.6-cm accuracy. Moreover, a power management ASIC, including a high efficiency active rectifier and automatic coil resonance tuning, was fabricated in a 0.35-μm 4M2P standard CMOS process for the mobile unit. The EnerCage-HC achieves a max/min PTE of 36.3%/16.1% at the nominal height of 7 cm. In vivo experiments were conducted on freely behaving rats by continuously delivering 24 mW to the mobile unit for >7 h inside a standard homecage. PMID:26257586

Molecular Weight Measurement of Biobased Furan Polyamides via Non-Aqueous Potentiometric Titration

DTIC Science & Technology

2013-06-01

electromagnetic fields, all titrations were completed in a chemical hood, which acted as a Faraday cage (a shield used to blocks external static and...while using DMF as a solvent. Additionally, no Faraday cage was used in the experimental setup, so the titrations were conducted inside the chemical...monomer was becoming more soluble in glacial acetic acid and the amount of chlorobenzene had less of an effect on the solution properties (i.e

Prediction of clathrate structure type and guest position by molecular mechanics.

PubMed

Fleischer, Everly B; Janda, Kenneth C

2013-05-16

The clathrate hydrates occur in various types in which the number, size, and shape of the various cages differ. Usually the clathrate type of a specific guest is predicted by the size and shape of the molecular guest. We have developed a methodology to determine the clathrate type employing molecular mechanics with the MMFF force field employing a strategy to calculate the energy of formation of the clathrate from the sum of the guest/cage energies. The clathrate type with the most negative (most stable) energy of formation would be the type predicted (we mainly focused on type I, type II, or bromine type). This strategy allows for a calculation to predict the clathrate type for any cage guest in a few minutes on a laptop computer. It proved successful in predicting the clathrate structure for 46 out of 47 guest molecules. The molecular mechanics calculations also provide a prediction of the guest position within the cage and clathrate structure. These predictions are generally consistent with the X-ray and neutron diffraction studies. By supplementing the diffraction study with molecular mechanics, we gain a more detailed insight regarding the details of the structure. We have also compared MM calculations to studies of the multiple occupancy of the cages. Finally, we present a density functional calculation that demonstrates that the inside of the clathrates cages have a relatively uniform and low electrostatic potential in comparison with the outside oxygen and hydrogen atoms. This implies that van der Waals forces will usually be dominant in the guest-cage interactions.

First field trials with fungi against Anoplophora glabripennis

Treesearch

Thomas Dubois; Ann Hajek; Hu Jiafu; Zengzhi Li

2003-01-01

We have been evaluating the use of entomopathogenic fungi against A. glabripennis; so far, 20 strains have been isolated belonging to three species, 14 strains have been tested in the laboratory, five strains have been evaluated in caged field trials and two strains have been tested in the open field.

CAGE IIIA Distributed Simulation Design Methodology

DTIC Science & Technology

2014-05-01

2 VHF Very High Frequency VLC Video LAN Codec – an Open-source cross-platform multimedia player and framework VM Virtual Machine VOIP Voice Over...Implementing Defence Experimentation (GUIDEx). The key challenges for this methodology are with understanding how to: • design it o define the...operation and to be available in the other nation’s simulations. The challenge for the CAGE campaign of experiments is to continue to build upon this

Bergamot versus beetle: evidence for intraspecific chemical specialization

PubMed Central

Keefover-Ring, Ken

2015-01-01

A large proportion of phytophagous insects show host plant specificity (monophagy or oligophagy), often determined by host secondary chemistry. Yet, even specialists can be negatively affected by host chemistry at high levels or with novel compounds, which may manifest itself if their host species is chemically variable. This study tested for reciprocal effects of a specialist tortoise beetle (Physonota unipunctata) feeding on a host plant (Monarda fistulosa) with two monoterpene chemotypes [thymol (T) and carvacrol (C)] using a controlled field experiment where larvae fed on caged plants of both chemotypes, haphazardly collected natural plants with and without beetle damage, and growth chamber experiments where larvae that hatched and briefly fed on one chemotype were reared on either chemotype. In the field experiment, plant chemotype did not affect larval weight or length, but did influence larval survival with almost 8.3 % more surviving on T plants. Herbivores reduced seed head area (86.5 % decrease), stem mass (41.2 %) and stem height (21.1 %) of caged plants, but this was independent of host chemotype. Natural plants experienced similar reductions in these variables (74.0, 41.4 and 8.7 %) and T chemotypes were more frequently damaged. In the growth chamber, larval relative growth rate (RGR) differed for both feeding history and year. Larvae from T natal plants reared on T hosts grew at almost twice the rate of those from C and reared on T. Larvae from either T or C natal plants reared on C plants showed intermediate growth rates. Additional analyses revealed natal plant chemotype as the most important factor, with the RGR of larvae from T natal plants almost one-third higher than that of those from C natal plants. These cumulative results demonstrate intraspecific variation in plant resistance that may lead to herbivore specialization on distinct host chemistry, which has implications for the evolutionary trajectory of both the insect and plant species. PMID:26578745

Bergamot versus beetle: evidence for intraspecific chemical specialization.

PubMed

Keefover-Ring, Ken

2015-11-16

A large proportion of phytophagous insects show host plant specificity (monophagy or oligophagy), often determined by host secondary chemistry. Yet, even specialists can be negatively affected by host chemistry at high levels or with novel compounds, which may manifest itself if their host species is chemically variable. This study tested for reciprocal effects of a specialist tortoise beetle (Physonota unipunctata) feeding on a host plant (Monarda fistulosa) with two monoterpene chemotypes [thymol (T) and carvacrol (C)] using a controlled field experiment where larvae fed on caged plants of both chemotypes, haphazardly collected natural plants with and without beetle damage, and growth chamber experiments where larvae that hatched and briefly fed on one chemotype were reared on either chemotype. In the field experiment, plant chemotype did not affect larval weight or length, but did influence larval survival with almost 8.3 % more surviving on T plants. Herbivores reduced seed head area (86.5 % decrease), stem mass (41.2 %) and stem height (21.1 %) of caged plants, but this was independent of host chemotype. Natural plants experienced similar reductions in these variables (74.0, 41.4 and 8.7 %) and T chemotypes were more frequently damaged. In the growth chamber, larval relative growth rate (RGR) differed for both feeding history and year. Larvae from T natal plants reared on T hosts grew at almost twice the rate of those from C and reared on T. Larvae from either T or C natal plants reared on C plants showed intermediate growth rates. Additional analyses revealed natal plant chemotype as the most important factor, with the RGR of larvae from T natal plants almost one-third higher than that of those from C natal plants. These cumulative results demonstrate intraspecific variation in plant resistance that may lead to herbivore specialization on distinct host chemistry, which has implications for the evolutionary trajectory of both the insect and plant species. Published by Oxford University Press on behalf of the Annals of Botany Company.

The effect of perches in cages during pullet rearing and egg laying on hen performance, foot health, and plumage.

PubMed

Hester, P Y; Enneking, S A; Jefferson-Moore, K Y; Einstein, M E; Cheng, H W; Rubin, D A

2013-02-01

Enrichment of pullet cages with perches has not been studied. Our objective was to determine if access to metal perches during all or part of the life cycle of caged White Leghorns affected egg traits, foot health, and feather condition. Treatment 1 represented control chickens that never had access to perches during their life cycle. Treatment 2 hens had perches only during the egg laying phase of the life cycle (17 to 71 wk of age), whereas treatment 3 chickens had perches during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens always had access to perches (0 to 71 wk of age). Comparisons between chickens that always had perches with controls that never had perches showed similar performance relative to egg production, cracked eggs, egg weight, shell weight, % shell, and shell thickness. More dirty eggs occurred in laying cages with perches. Feed usage increased resulting in poorer feed efficiency in hens with perch exposure during the pullet phase with no effect during egg laying. Perches did not affect hyperkeratosis of toes and feet. The back claw at 71 wk of age broke less if hens had prior experience with perches during the pullet phase. In contrast, during egg laying, the back claw at 71 wk of age broke more due to the presence of perches in laying cages. Perches in laying cages resulted in shorter trimmed claws and improved back feather scores, but caused poorer breast and tail feather scores. In conclusion, enriching conventional cages with perches during the entire life cycle resulted in similar hen performance compared with controls. Fewer broken back claws but poorer feed efficiency occurred because of prior experience with perches as pullets. Perch presence during egg laying improved back feather scores with more trimmed nails but caused more dirty eggs, broken back claws, and poorer breast and tail feather scores. Although perches allow chickens to express their natural perching instinct, it was not without causing welfare problems.

Can ménage-a-trois be used for controlling insects?

PubMed

Suckling, D M; Jang, E B; Carvalho, L A; Nagata, J T; Schneider, E L; El-Sayed, A M

2007-08-01

We propose a new cross-species disruption approach that might be capable of interrupting mating of one species that uses another insect species as the mercenary agent. We argue that insects treated with a sufficiently powerful attractant for a second species might interfere with mating of one or both species, for example, by leading males astray in pursuit of the false trails created by suitably dosing individuals of the first species. Our reciprocal test systems used (1) methyl eugenol, an attractant for male oriental fruit flies (Bactrocera dorsalis), applied to melon flies (B. cucurbitae) and (2) cuelure, a lure for male melon flies, applied to B. dorsalis. There was no mortality 1 week after either attractant was applied to individual flies at doses up to 100 ng, which was effective in attracting insects in a field cage and in the field. In wind tunnel choice tests, 100 ng of either lure topically applied to tethered flies attracted fruit fly males of the second species, which exhibited prolonged bouts of physically disruptive behaviors including chasing and bumping. In small cages, treatment of males did not reduce mating of either species, with one group of three (ménage) per cage. However, in large field cages with multiple pairs of both species present, there was a significant reduction in the mating of melon flies resulting from methyl eugenol applied to males compared to untreated controls. The treatment of oriental fruit flies with cuelure also reduced their mating to a lesser extent. These results do not yet provide the practical proof of this new concept for pest management, but other model systems may be more appropriate. This work is novel in presenting attractants on a moving target, in this case, another insect species.

On-line diagnosis of defaults on squirrel cage motors using FEM

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

Bentounsi, A.; Nicolas, A.

1998-09-01

In industry, the predictive maintenance has become a strategic concept. Economic interest of on-line diagnosis of faults in electric machines gave rise to various researches in that field. This paper proposes a local approach to tackle the problem of breaking bars and end-rings of squirrel cage in induction machines based mainly on the signature of the local variables, such as the normal flux density. This allows a finer analysis, by use of a finite element based simulation.

Mice selectively bred for open-field thigmotaxis: life span and stability of the selection trait.

PubMed

Leppänen, Pia K; Ewalds-Kvist, S Béatrice M; Selander, Ritva-Kajsa

2005-04-01

In 2 experiments, the authors examined 69 mice selectively bred for high or low levels of open-field (OF) thigmotactic behavior (high open-field thigmotaxis [HOFT] and low open-field thigmotaxis [LOFT], respectively). They found that the strains differed in defecation during the 60-min exposure to the OF. Furthermore, the strains differed with regard to their life spans: The more thigmotactic HOFT mice lived longer than the LOFT mice. The strains were not differentiated by food intake or excretion. The strain difference in thigmotaxis was not age dependent, and it persisted in the home-cage condition as well. Neither the location (center or wall) of the starting point nor the shape (circular or square) of the OF arena affected the difference in wall-seeking behavior between the two strains. The authors concluded that the difference in thigmotaxis (or emotionality) between the HOFT and LOFT mice is a stable and robust feature of these animals.

Quantum rotations in natural methane-clathrates from the Pacific sea-floor

NASA Astrophysics Data System (ADS)

Gutt, C.; Asmussen, B.; Press, W.; Merkl, C.; Casalta, H.; Greinert, J.; Bohrmann, G.; Tse, J. S.; Hüller, A.

1999-11-01

We report inelastic neutron scattering experiments from natural methane hydrates sampled from the Pacific sea-floor during an expedition of the research ship SONNE. The experiments verify directly the content of methane by measuring the rotational spectrum of the CH4 molecules. The existence of almost free rotational levels excludes off-center positions of the molecules in the cages. In addition we could assign the observed peaks in the energy regime up to 5 meV to rotational excitations only. The observed relative sharp excitations prove a surprisingly good crystallinity of the geological sample. The finite width is attributed to frozen-in hydrogen disorder of the ice cages.

Role of Surface Charge Density in Nanoparticle-templated Assembly of Bromovirus Protein Cages

PubMed Central

Daniel, Marie-Christine; Tsvetkova, Irina B.; Quinkert, Zachary T.; Murali, Ayaluru; De, Mrinmoy; Rotello, Vincent M.; Kao, C. Cheng; Dragnea, Bogdan

2010-01-01

Self-assembling icosahedral protein cages have potencially useful physical and chemical characteristics for a variety of nanotechnology applications, ranging from therapeutic or diagnostic vectors to building blocks for hierarchical materials. For application-specific functional control of protein cage assemblies, a deeper understanding of the interaction between the protein cage and its payload is necessary. Protein-cage encapsulated nanoparticles, with their well-defined surface chemistry, allow for systematic control over key parameters of encapsulation such as the surface charge, hydrophobicity, and size. Independent control over these variables allows experimental testing of different assembly mechanism models. Previous studies done with Brome mosaic virus capsids and negatively-charged gold nanoparticles indicated that the result of the self-assembly process depends on the diameter of the particle. However, in these experiments, the surface-ligand density was maintained at saturation levels, while the total charge and the radius of curvature remained coupled variables, making the interpretation of the observed dependence on the core size difficult. The current work furnishes evidence of a critical surface charge density for assembly through an analysis aimed at decoupling the surface charge the core size. PMID:20575505

Survey of egg producers on the introduction of alternative housing systems for laying hens in Flanders, Belgium.

PubMed

Tuyttens, F A M; Sonck, B; Staes, M; Van Gansbeke, S; Van den Bogaert, T; Ampe, B

2011-04-01

In the context of the European Union ban on battery cages by 2012, a survey was conducted among Flemish egg producers (60% response rate, 140 completed questionnaires) about the introduction and opinion of alternative housing systems. Belgium appears to be among the countries in the European Union that are slower to adopt alternative housing. Belgium's egg industry is thus likely to undergo drastic changes to comply with the 2012 deadline. As of 2010, the battery cage was the dominant housing system (56% housing units, 67% hens), followed by floor housing (33% housing units, 15% hens) and aviary (10% housing units, 15% hens), whereas colony cages and furnished cages were extremely rare. Future- and market-oriented production was the most important reason for choosing a certain type of alternative system, although the importance of hen performance and amount of labor seemed to increase. A quarter of the producers with battery cages had detailed plans to convert to an alternative system (most planned to install aviaries, followed by colony cages, furnished cages, and floor housing) by 2012. Many older farmers indicated that they would stop farming, whereas others found it more profitable to delay the conversion as long as possible. Apart from hen welfare, producers expressed a negative opinion (relative to battery cages) about noncage systems and, to a lesser extent, furnished cages. However, users of alternative systems reported being quite satisfied, except for the amount of labor and hen health. The housing system had several effects on user satisfaction: positive effect of flock size, negative effect of experience with battery cages, and negative effect of outdoor area on hen health. Although not all opinions were supported by evidence, such surveys provide feedback about the success of alternative systems in practice. This information is valuable to further improve these systems and to producers who have yet to convert. Moreover, producer attitude may determine the extent to which legally imposed changes in husbandry environment result in the desired improvement of hen welfare in practice.

Experimental investigations about the effect of trace amount of propane on the formation of mixed hydrates of methane and propane

NASA Astrophysics Data System (ADS)

Cai, W.; Lu, H.; Huang, X.

2016-12-01

In natural gas hydrates, some heavy hydrocarbons are always detected in addition to methane. However, it is still not well understood how the trace amount of heavy gas affect the hydrate properties. Intensive studies have been carried out to study the thermodynamic properties and structure types of mixed gases hydrates, but comparatively few investigations have been carried out on the cage occupancies of guest molecules in mixed gases hydrates. For understanding how trace amount of propane affects the formation of mixed methane-propane hydrates, X-ray diffraction, Raman spectroscopy, and gas chromatography were applied to the synthesized mixed methane-propane hydrate specimens, to get their structural characteristics (structure type, structural parameters, cage occupancy, etc.) and gas compositions. The mixed methane-propane hydrates were prepared by reacting fine ice powders with various gas mixtures of methane and propane. When the propane content was below 0.4%, the hydrates synthesized were found containing both sI methane hydrate and sII methane-propane hydrate; while the hydrates were found always sII when propane was over certain content. Detail studies about the cage occupancies of propane and methane in sII hydrate revealed that: 1) with the increase in propane content of methane-propane mixture, the occupancy of propane in large cage increased as accompanied with the decrease in methane occupancy in large cage, however the occupancy of methane in small cage didn't experience significant change; 2) temperature and pressure seemed no obvious influence on cage occupancy.

Effects of Japanese beetle (Coleoptera: Scarabaeidae) and silk clipping in field corn.

PubMed

Steckel, Sandy; Stewart, S D; Tindall, K V

2013-10-01

Japanese beetle (Popillia japonica Newman) is an emerging silk-feeding insect found in fields in the lower Corn Belt and Midsouthern United States. Studies were conducted in 2010 and 2011 to evaluate how silk clipping in corn affects pollination and yield parameters. Manually clipping silks once daily had modest effects on yield parameters. Sustained clipping by either manually clipping silks three times per day or by caging Japanese beetles onto ears affected total kernel weight if it occurred during early silking (R1 growth stage). Manually clipping silks three times per day for the first 5 d of silking affected the number of kernels per ear, total kernel weight, and the weight of individual kernels. Caged beetles fed on silks and, depending on the number of beetles caged per ear, reduced the number of kernels per ear. Caging eight beetles per ear significantly reduced total kernel weight compared with noninfested ears. Drought stress before anthesis appeared to magnify the impact of silk clipping by Japanese beetles. There was evidence of some compensation for reduced pollination by increasing the size of pollinated kernels within the ear. Our results showed that it requires sustained silk clipping during the first week of silking to have substantial impacts on pollination and yield parameters, at least under good growing conditions. Some states recommend treating for Japanese beetle when three Japanese beetles per ear are found, silks are clipped to < 13 mm, and pollination is < 50% complete, and that recommendation appears to be adequate.

Field bioassay of Metarhizium anisopliae strains to control the poultry red mite Dermanyssus gallinae.

PubMed

Tavassoli, M; Allymehr, M; Pourseyed, S H; Ownag, A; Bernousi, I; Mardani, K; Ghorbanzadegan, M; Shokrpoor, S

2011-06-10

The poultry red mite, Dermanyssus gallinae is one of the most economically deleterious ectoparasite of laying hens worldwide. To evaluate the efficacy of three strains (V245, 3247 and 715C) of entomopathogenic fungus Metarhizium anisopliae with potential as acaricides against D. gallinae, this investigation was carried out in a commercial caged laying poultry farm in Naghedeh, West Azarbaijan of Iran. The parasite infestation already existed in the farm. Sunflower oil suspension of all fungal strains, each in two concentrations (1×10(7) and 1×10(9) conidia/ml) were used separately as spray on hens and cages, and in the control group the cages were only sprayed with sunflower oil and sterile distilled water. For estimating the population rate of mites before and after treatment, special cardboard traps were fixed to cages during a 1-month period. The traps were placed on weeks -1, 0, 1, 2 and 3 and always removed after 1 w. The results showed that the population rates post fungal treatment with the lower concentration were not significantly different compared to the control group. However, the reduction in mite numbers induced by all three strains at the concentration of 1×10(9) conidia/ml was significantly higher than the control (P<0.05). The results revealed that under field conditions, higher concentrations of M. anisopliae will be required for controlling D. gallinae. Copyright © 2011 Elsevier B.V. All rights reserved.

Enhanced nonlinear optical response of an endohedral metallofullerene through metal-to-cage charge transfer

NASA Astrophysics Data System (ADS)

Heflin, J. R.; Marciu, D.; Figura, C.; Wang, S.; Burbank, P.; Stevenson, S.; Dorn, H. C.

1998-06-01

A new mechanism for increasing the third-order nonlinear optical susceptibility, χ(3), is described for endohedral metallofullerenes. A two to three orders of magnitude increase in the nonlinear response is reported for degenerate four-wave mixing experiments conducted with solutions of Er2@C82 (isomer III) relative to empty-cage fullerenes. A value of -8.7×10-32esu is found for the molecular susceptibility, γxyyx, of Er2@C82 compared to previously reported values of γxxxx=3×10-34 esu and γxyyx=4×10-35 esu for C60. The results confirm the importance of the metal-to-cage charge-transfer mechanism for enhancing the nonlinear optical response in endohedral metallofullerenes.

A tethering system for direct measurement of cardiovascular function in the caged baboon

NASA Technical Reports Server (NTRS)

Byrd, L. D.

1979-01-01

A device suitable for the continuous measurement of physiological activity in large, conscious monkeys has permitted the direct recording of systemic arterial blood pressure and heart rate in caged baboons. The device comprises a lightweight fiberglass backpack, retained in place on the baboon by a thoracic elastic band and shoulder straps, and a flexible stainless steel tether connecting the pack to an electrocannular slip-ring in the top center of the baboon's cage. A chronically indwelling arterial catheter inserted retrograde into the abdominal aorta via the internal iliac artery and connected to a small pressure transducer on the pack provides direct measurement of blood pressure and heart rate. Body fluids can be sampled or drugs administered via an indwelling catheter in the inferior vena cava. Electrical and fluid connections between the fiberglass pack and recording and infusion equipment located outside the cage pass through the flexible tether and remain protected from the subject. The reliability of the tethering system has been demonstrated in physiological, pharmacological, and behavioral experiments with baboons.

Cell tracking with caged xenon: using cryptophanes as MRI reporters upon cellular internalization.

PubMed

Klippel, Stefan; Döpfert, Jörg; Jayapaul, Jabadurai; Kunth, Martin; Rossella, Federica; Schnurr, Matthias; Witte, Christopher; Freund, Christian; Schröder, Leif

2014-01-07

Caged xenon has great potential in overcoming sensitivity limitations for solution-state NMR detection of dilute molecules. However, no application of such a system as a magnetic resonance imaging (MRI) contrast agent has yet been performed with live cells. We demonstrate MRI localization of cells labeled with caged xenon in a packed-bed bioreactor working under perfusion with hyperpolarized-xenon-saturated medium. Xenon hosts enable NMR/MRI experiments with switchable contrast and selectivity for cell-associated versus unbound cages. We present MR images with 10(3) -fold sensitivity enhancement for cell-internalized, dual-mode (fluorescence/MRI) xenon hosts at low micromolar concentrations. Our results illustrate the capability of functionalized xenon to act as a highly sensitive cell tracer for MRI detection even without signal averaging. The method will bridge the challenging gap for translation to in vivo studies for the optimization of targeted biosensors and their multiplexing applications. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ferritin cage for encapsulation and delivery of bioactive nutrients: From structure, property to applications.

PubMed

Zang, Jiachen; Chen, Hai; Zhao, Guanghua; Wang, Fudi; Ren, Fazheng

2017-11-22

Ferritin is a class of naturally occurring iron storage proteins, which is distributed widely in animal, plant, and bacteria. It usually consists of 24 subunits that form a hollow protein shell with high symmetry. One holoferritin molecule can store up to 4500 iron atom within its inner cavity, and it becomes apoferritin upon removal of iron from the cavity. Recently, scientists have subverted these nature functions and used reversibly self-assembled property of apoferritin cage controlled by pH for the encapsulation and delivery of bioactive nutrients or anticancer drug. In all these cases, the ferritin cages shield their cargo from the influence of external conditions and provide a controlled microenvironment. More importantly, upon encapsulation, ferritin shell greatly improved the water solubility, thermal stability, photostability, and cellular uptake activity of these small bioactive compounds. This review aims to highlight recent advances in applications of ferritin cage as a novel vehicle in the field of food science and nutrition. Future outlooks are highlighted with the aim to suggest a research line to follow for further studies.

Focusing of high intensity ultrasound through the rib cage using a therapeutic random phased array

PubMed Central

Bobkova, Svetlana; Gavrilov, Leonid; Khokhlova, Vera; Shaw, Adam; Hand, Jeffrey; #, ||

2010-01-01

A method for focusing high intensity ultrasound through a rib cage that aims to minimize heating of the ribs whilst maintaining high intensities at the focus (or foci) is proposed and tested theoretically and experimentally. Two approaches, one based on geometric acoustics and the other accounting for diffraction effects associated with propagation through the rib cage, are investigated theoretically for idealized source conditions. It is shown that for an idealized radiator the diffraction approach provides a 23% gain in peak intensity and results in significantly less power losses on the ribs (1% versus 7.5% of the irradiated power) compared with the geometric one. A 2D 1-MHz phased array with 254 randomly distributed elements, tissue mimicking phantoms, and samples of porcine rib cages are used in experiments; the geometric approach is used to configure how the array is driven. Intensity distributions are measured in the plane of the ribs and in the focal plane using an infra-red camera. Theoretical and experimental results show that it is possible to provide adequate focusing through the ribs without overheating them for a single focus and several foci, including steering at ± 10–15 mm off and ± 20 mm along the array axis. Focus splitting due to the periodic spatial structure of ribs is demonstrated both in simulations and experiments; the parameters of splitting are quantified. The ability to produce thermal lesions with a split focal pattern in ex vivo porcine tissue placed beyond the rib phantom is also demonstrated. The results suggest that the method is potentially useful for clinical applications of HIFU for which the rib cage lies between the transducer(s) and the targeted tissue. PMID:20510186

A mobile phone Faraday cage

NASA Astrophysics Data System (ADS)

French, M. M. J.

2011-05-01

A Faraday cage is an interesting physical phenomenon where an electromagnetic wave can be excluded from a volume of space by enclosure with an electrically conducting material. The practical application of this in the classroom is to block the signal to a mobile phone by enclosing it in a metal can. The background of the physics behind this is described in some detail, and this is followed by a explanation of some demonstrations and experiments which I have used.

Hatching success and predation of Bog Turtle (Glyptemys muhlenbergii) eggs in New Jersey and Pennsylvania

USGS Publications Warehouse

Zappalorti, Robert T.; Tutterow, Annalee M.; Pittman, Shannon E.; Lovich, Jeffrey E.

2017-01-01

Nest-site selection by most turtles affects the survival of females and their offspring. Although bog turtles (Glyptemys muhlenbergii) do not typically leave their wetlands for nesting, nest-site selection can impact hatching success and hatchling survival. Between 1974 and 2012, we monitored the fates of 258 bog turtle eggs incubated in the field and 91 eggs incubated under laboratory conditions from 11 different bogs, fens, or wetland complexes in New Jersey and Pennsylvania. Laboratory-incubated eggs exhibited the greatest hatching success (81%), but we did not detect a significant difference in hatching success between nests protected with predator excluder cages (43%) and unprotected nests (33%). However, we found significantly lower predation rates in protected nests, suggesting that while predator excluder cages successfully reduced predation, other environmental factors persisted to reduce egg survival in the field. Natural hatching success was potentially reduced by poor weather conditions, which may have resulted in embryo developmental problems, dehydration, or embryos drowning in the egg. Our results suggest that egg depredation, coupled with embryo developmental problems and infertility, are limiting factors to hatching success in our study populations. Using predator excluder cages to protect bog turtle eggs in the field, or incubating eggs in the laboratory and releasing hatchlings at original nesting areas, may be an effective conservation tool for recovering populations of this federally threatened species.

Ground-based assessment of JAXA mouse habitat cage unit by mouse phenotypic studies

PubMed Central

Shimbo, Miki; Kudo, Takashi; Hamada, Michito; Jeon, Hyojung; Imamura, Yuki; Asano, Keigo; Okada, Risa; Tsunakawa, Yuki; Mizuno, Seiya; Yagami, Ken-ichi; Ishikawa, Chihiro; Li, Haiyan; Shiga, Takashi; Ishida, Junji; Hamada, Juri; Murata, Kazuya; Ishimaru, Tomohiro; Hashimoto, Misuzu; Fukamizu, Akiyoshi; Yamane, Mutsumi; Ikawa, Masahito; Morita, Hironobu; Shinohara, Masahiro; Asahara, Hiroshi; Akiyama, Taishin; Akiyama, Nobuko; Sasanuma, Hiroki; Yoshida, Nobuaki; Zhou, Rui; Wang, Ying-Ying; Ito, Taito; Kokubu, Yuko; Noguchi, Taka-aki K.; Ishimine, Hisako; Kurisaki, Akira; Shiba, Dai; Mizuno, Hiroyasu; Shirakawa, Masaki; Ito, Naoki; Takeda, Shin; Takahashi, Satoru

2016-01-01

The Japan Aerospace Exploration Agency developed the mouse Habitat Cage Unit (HCU) for installation in the Cell Biology Experiment Facility (CBEF) onboard the Japanese Experimental Module (“Kibo”) on the International Space Station. The CBEF provides “space-based controls” by generating artificial gravity in the HCU through a centrifuge, enabling a comparison of the biological consequences of microgravity and artificial gravity of 1 g on mice housed in space. Therefore, prior to the space experiment, a ground-based study to validate the habitability of the HCU is necessary to conduct space experiments using the HCU in the CBEF. Here, we investigated the ground-based effect of a 32-day housing period in the HCU breadboard model on male mice in comparison with the control cage mice. Morphology of skeletal muscle, the thymus, heart, and kidney, and the sperm function showed no critical abnormalities between the control mice and HCU mice. Slight but significant changes caused by the HCU itself were observed, including decreased body weight, increased weights of the thymus and gastrocnemius, reduced thickness of cortical bone of the femur, and several gene expressions from 11 tissues. Results suggest that the HCU provides acceptable conditions for mouse phenotypic analysis using CBEF in space, as long as its characteristic features are considered. Thus, the HCU is a feasible device for future space experiments. PMID:26822934

Ground-based assessment of JAXA mouse habitat cage unit by mouse phenotypic studies.

PubMed

Shimbo, Miki; Kudo, Takashi; Hamada, Michito; Jeon, Hyojung; Imamura, Yuki; Asano, Keigo; Okada, Risa; Tsunakawa, Yuki; Mizuno, Seiya; Yagami, Ken-Ichi; Ishikawa, Chihiro; Li, Haiyan; Shiga, Takashi; Ishida, Junji; Hamada, Juri; Murata, Kazuya; Ishimaru, Tomohiro; Hashimoto, Misuzu; Fukamizu, Akiyoshi; Yamane, Mutsumi; Ikawa, Masahito; Morita, Hironobu; Shinohara, Masahiro; Asahara, Hiroshi; Akiyama, Taishin; Akiyama, Nobuko; Sasanuma, Hiroki; Yoshida, Nobuaki; Zhou, Rui; Wang, Ying-Ying; Ito, Taito; Kokubu, Yuko; Noguchi, Taka-Aki K; Ishimine, Hisako; Kurisaki, Akira; Shiba, Dai; Mizuno, Hiroyasu; Shirakawa, Masaki; Ito, Naoki; Takeda, Shin; Takahashi, Satoru

2016-05-20

The Japan Aerospace Exploration Agency developed the mouse Habitat Cage Unit (HCU) for installation in the Cell Biology Experiment Facility (CBEF) onboard the Japanese Experimental Module ("Kibo") on the International Space Station. The CBEF provides "space-based controls" by generating artificial gravity in the HCU through a centrifuge, enabling a comparison of the biological consequences of microgravity and artificial gravity of 1 g on mice housed in space. Therefore, prior to the space experiment, a ground-based study to validate the habitability of the HCU is necessary to conduct space experiments using the HCU in the CBEF. Here, we investigated the ground-based effect of a 32-day housing period in the HCU breadboard model on male mice in comparison with the control cage mice. Morphology of skeletal muscle, the thymus, heart, and kidney, and the sperm function showed no critical abnormalities between the control mice and HCU mice. Slight but significant changes caused by the HCU itself were observed, including decreased body weight, increased weights of the thymus and gastrocnemius, reduced thickness of cortical bone of the femur, and several gene expressions from 11 tissues. Results suggest that the HCU provides acceptable conditions for mouse phenotypic analysis using CBEF in space, as long as its characteristic features are considered. Thus, the HCU is a feasible device for future space experiments.

Application of bicyclic and cage compounds

NASA Technical Reports Server (NTRS)

Clark, R. D.; Archuleta, B. S.

1976-01-01

The results of a literature survey of the field of bicyclic and cage compounds were presented, with the objective of identifying those types of compounds with unusual physical and chemical stability, and determining what practical applications have been found for these compounds. Major applications have been as polymers, polymer additives, medicinals, and pesticides. Lesser applications have included fuels, fuel additives, lubricants, lubricant additives, and perfumes. Several areas where further work might be useful were also outlined; these are primarily in the areas of polymers, polymer additives, medicinals, and synthetic lubricants.

The influence of cage conditioning on the performance and behavior of Japanese flounder reared for stock enhancement: Burying, feeding, and threat response

NASA Astrophysics Data System (ADS)

Walsh, Michelle L.; Masuda, Reiji; Yamashita, Yoh

2014-01-01

Flatfish reared for stock enhancement often exhibit irregular behavioral patterns compared with wild conspecifics. These “deficits”, mostly attributed to the unnatural characteristics of the hatchery environment, are assumed to translate to increased predation risk. Initially releasing fish in predator-free conditioning cages may help flatfish adjust to the wild environment, establish burial skills, begin pigment change, recover from transport stress, and experience natural (live) food sources before full release into the wild. However, the impact of cage conditioning on the performance and behavior of flatfish has yet to be fully assessed. We conducted video trials with 10-cm, hatchery-reared Japanese flounder, Paralichthys olivaceus, in sand-bottomed aquaria to assess four treatments of flounder: (1) reared fish cage conditioned for 7 d in the shallow coast, (2) reared fish directly from hatchery tanks, (3) wild fish, and (4) reared fish released directly from hatchery tanks into the wild and then recaptured after 6 d at large. Burying ability, predation, and threat response to a model predator were examined. Wild fish buried most, followed by cage conditioned, and released-then-recaptured and non-conditioned (directly from tank) fish. Wild and conditioned fish revealed much lower variation in total movement duration, which corresponded with lower levels and variation in prey vertical movement. Fish of all condition types exhibited a lower number of attacks and off-bottom swimming events, and a lower movement duration when the model predator was in motion versus when it was still. This study is the first to evaluate the behavioral mechanisms of hatchery-reared flatfish that have been cage-conditioned or released-then-recaptured. In addition, we provide evidence that cage conditioning can enhance the performance of released flatfish.

Reintroduction of the highly endangered mollusk Patella ferruginea Gmelin, 1791 in an MPA: A novel approach to achieve high survival rates

NASA Astrophysics Data System (ADS)

Zarrouk, Anis; Romdhane, Mohamed Salah; Espinosa, Free

2018-03-01

Patella ferruginea is the most endangered marine invertebrate of western Mediterranean rocky shores. After a study of one of its most important populations in the Zembra Archipelago National Park (Tunisia), a new protocol for the translocation of the species (size: 4-8 cm) was adopted. The first translocation was made in June 2014 in the same archipelago, where 94 specimens were moved from Zembretta to Zembra Island and marked (62 protected by cages, 20 with no cages and 60 as controls). The second translocation was performed in August 2014 (110 specimens) from Zembra to La Galite Island (185 km away). High mortality was registered during transport. The remaining individuals (39) were marked and placed in cages on the rocky shores of Galite Island, then monitored until November 2015. Growth and survival rates were measured in both translocated and control populations. The highest mortality rates were observed during the initial three days after translocation, especially for individuals with no cage protection. After a 697-day survey on Zembra Island, survival rates of 58%, 25% and 85% were observed for cage, no-cage and control populations, respectively. After a 457-day survey on La Galite Island, the survival rate was 18%. Limpets>6 cm in size had the highest survival rate among Zembra-translocated populations, whereas translocated limpets of 4-6 cm in size showed the highest survival rate in La Galite. The growth rates for both translocated populations were higher than the rate observed for controls. Our translocation experiment shows the importance of cage protection and initial limpet size for survival.

Comparing alternative methods for holding virgin honey bee queens for one week in mailing cages before mating.

PubMed

Bigio, Gianluigi; Grüter, Christoph; Ratnieks, Francis L W

2012-01-01

In beekeeping, queen honey bees are often temporarily kept alive in cages. We determined the survival of newly-emerged virgin honey bee queens every day for seven days in an experiment that simultaneously investigated three factors: queen cage type (wooden three-hole or plastic), attendant workers (present or absent) and food type (sugar candy, honey, or both). Ten queens were tested in each of the 12 combinations. Queens were reared using standard beekeeping methods (Doolittle/grafting) and emerged from their cells into vials held in an incubator at 34C. All 12 combinations gave high survival (90 or 100%) for three days but only one method (wooden cage, with attendants, honey) gave 100% survival to day seven. Factors affecting queen survival were analysed. Across all combinations, attendant bees significantly increased survival (18% vs. 53%, p<0.001). In addition, there was an interaction between food type and cage type (p<0.001) with the honey and plastic cage combination giving reduced survival. An additional group of queens was reared and held for seven days using the best method, and then directly introduced using smoke into queenless nucleus colonies that had been dequeened five days previously. Acceptance was high (80%, 8/10) showing that this combination is also suitable for preparing queens for introduction into colonies. Having a simple method for keeping newly-emerged virgin queens alive in cages for one week and acceptable for introduction into queenless colonies will be useful in honey bee breeding. In particular, it facilitates the screening of many queens for genetic or phenotypic characteristics when only a small proportion meets the desired criteria. These can then be introduced into queenless hives for natural mating or insemination, both of which take place when queens are one week old.

Comparing Alternative Methods for Holding Virgin Honey Bee Queens for One Week in Mailing Cages before Mating

PubMed Central

Bigio, Gianluigi; Grüter, Christoph; Ratnieks, Francis L. W.

2012-01-01

In beekeeping, queen honey bees are often temporarily kept alive in cages. We determined the survival of newly-emerged virgin honey bee queens every day for seven days in an experiment that simultaneously investigated three factors: queen cage type (wooden three-hole or plastic), attendant workers (present or absent) and food type (sugar candy, honey, or both). Ten queens were tested in each of the 12 combinations. Queens were reared using standard beekeeping methods (Doolittle/grafting) and emerged from their cells into vials held in an incubator at 34C. All 12 combinations gave high survival (90 or 100%) for three days but only one method (wooden cage, with attendants, honey) gave 100% survival to day seven. Factors affecting queen survival were analysed. Across all combinations, attendant bees significantly increased survival (18% vs. 53%, p<0.001). In addition, there was an interaction between food type and cage type (p<0.001) with the honey and plastic cage combination giving reduced survival. An additional group of queens was reared and held for seven days using the best method, and then directly introduced using smoke into queenless nucleus colonies that had been dequeened five days previously. Acceptance was high (80%, 8/10) showing that this combination is also suitable for preparing queens for introduction into colonies. Having a simple method for keeping newly-emerged virgin queens alive in cages for one week and acceptable for introduction into queenless colonies will be useful in honey bee breeding. In particular, it facilitates the screening of many queens for genetic or phenotypic characteristics when only a small proportion meets the desired criteria. These can then be introduced into queenless hives for natural mating or insemination, both of which take place when queens are one week old. PMID:23166832

Social communication in mice--are there optimal cage conditions?

PubMed

Ferhat, Allain-Thibeault; Le Sourd, Anne-Marie; de Chaumont, Fabrice; Olivo-Marin, Jean-Christophe; Bourgeron, Thomas; Ey, Elodie

2015-01-01

Social communication is heavily affected in patients with neuropsychiatric disorders. Accordingly, mouse models designed to study the mechanisms leading to these disorders are tested for this phenotypic trait. Test conditions vary between different models, and the effect of these test conditions on the quantity and quality of social interactions and ultrasonic communication is unknown. The present study examines to which extent the habituation time to the test cage as well as the shape/size of the cage influence social communication in freely interacting mice. We tested 8 pairs of male mice in free dyadic social interactions, with two habituation times (20 min and 30 min) and three cage formats (rectangle, round, square). We tested the effect of these conditions on the different types of social contacts, approach-escape sequences, follow behavior, and the time each animal spent in the vision field of the other one, as well as on the emission of ultrasonic vocalizations and their contexts of emission. We provide for the first time an integrated analysis of the social interaction behavior and ultrasonic vocalizations. Surprisingly, we did not highlight any significant effect of habituation time and cage shape/size on the behavioral events examined. There was only a slight increase of social interactions with the longer habituation time in the round cage. Remarkably, we also showed that vocalizations were emitted during specific behavioral sequences especially during close contact or approach behaviors. The present study provides a protocol reliably eliciting social contacts and ultrasonic vocalizations in adult male mice. This protocol is therefore well adapted for standardized investigation of social interactions in mouse models of neuropsychiatric disorders.

The role of acoustic nonlinearity in tissue heating behind a rib cage using a high-intensity focused ultrasound phased array

NASA Astrophysics Data System (ADS)

Yuldashev, Petr V.; Shmeleva, Svetlana M.; Ilyin, Sergey A.; Sapozhnikov, Oleg A.; Gavrilov, Leonid R.; Khokhlova, Vera A.

2013-04-01

The goal of this study was to investigate theoretically the effects of nonlinear propagation in a high-intensity focused ultrasound (HIFU) field produced by a therapeutic phased array and the resultant heating of tissue behind a rib cage. Three configurations of focusing were simulated: in water, in water with ribs in the beam path and in water with ribs backed by a layer of soft tissue. The Westervelt equation was used to model the nonlinear HIFU field, and a 1 MHz phased array consisting of 254 circular elements was used as a boundary condition to the model. The temperature rise in tissue was modelled using the bioheat equation, and thermally necrosed volumes were calculated using the thermal dose formulation. The shapes of lesions predicted by the modelling were compared with those previously obtained in in vitro experiments at low-power sonications. Intensity levels at the face of the array elements that corresponded to the formation of high-amplitude shock fronts in the focal region were determined as 10 W cm-2 in the free field in water and 40 W cm-2 in the presence of ribs. It was shown that exposures with shocks provided a substantial increase in tissue heating, and its better spatial localization in the main focal region only. The relative effects of overheating ribs and splitting of the focus due to the periodic structure of the ribs were therefore reduced. These results suggest that utilizing nonlinear propagation and shock formation effects can be beneficial for inducing confined HIFU lesions when irradiating through obstructions such as ribs. Design of compact therapeutic arrays to provide maximum power outputs with lower intensity levels at the elements is necessary to achieve shock wave regimes for clinically relevant sonication depths in tissue.

The role of acoustic nonlinearity in tissue heating behind the rib cage using high intensity focused ultrasound phased array

PubMed Central

Yuldashev, Petr V.; Shmeleva, Svetlana M.; Ilyin, Sergey A.; Sapozhnikov, Oleg A.; Gavrilov, Leonid R.; Khokhlova, Vera A.

2013-01-01

The goal of this study was to investigate theoretically the effects of nonlinear propagation in a high intensity focused ultrasound (HIFU) field produced by a therapeutic phased array and the resultant heating of tissue behind a rib cage. Three configurations of focusing were simulated: in water, in water with ribs in the beam path, and in water with ribs backed by a layer of soft tissue. The Westervelt equation was used to model the nonlinear HIFU field and a 1 MHz phased array consisting of 254 circular elements was used as a boundary condition to the model. The temperature rise in tissue was modelled using the bioheat equation, and thermally necrosed volumes were calculated using the thermal dose formulation. The shapes of lesions predicted by the modelling were compared with those previously obtained in in vitro experiments at low power sonications. Intensity levels at the face of the array elements that corresponded to formation of high amplitude shock fronts in the focal region were determined as 10 W·cm−2 in the free field in water and 40 W·cm−2 in the presence of ribs. It was shown that exposures with shocks provided a substantial increase in tissue heating, and its better spatial localization in the main focal region only. The relative effects of overheating ribs and splitting of the focus due to the periodic structure of the ribs were therefore reduced. These results suggest that utilizing nonlinear propagation and shock formation effects can be beneficial for inducing confined HIFU lesions when irradiating through obstructions such as ribs. Design of compact therapeutic arrays to provide maximum power outputs with lower intensity levels at the elements is necessary to achieve shock wave regimes for clinically relevant sonication depths in tissue. PMID:23528338

Carcinogenicity of Black Rock Harbor sediment to the eastern oyster and trophic transfer of Black Rock Harbor carcinogens from the blue mussel to the winter flounder

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

Gardner, G.R.; Yevich, P.P.; Malcolm, A.R.

1991-01-01

The eastern oyster (Crassostrea virginica) developed neoplastic disorders when experimentally exposed both in the laboratory and field to chemically contaminated sediment from Black Rock Harbor (BRH), Bridgeport, Connecticut. Neoplasia was observed in oysters after 30 or 60 days of continuous exposure in a laboratory flow-through system to a 20 mg/L suspension of BRH sediment plus postexposure periods of 3, 30, or 60 days. Composite tumor incidence was 13.6% for both exposures. Tumor occurrence was highest in the renal excretory epithelium, followed in order by gill, gonad, gastrointestinal, heart, and embryonic neural tissue. Regression of experimental neoplasia was not observed whenmore » the stimulus was discontinued. In field experiments, gill neoplasms developed in oysters, deployed in cages for 30 days at BRH and 36 days at a BRH dredge material disposal area in Central Long Island Sound, and kidney and gastrointestinal neoplasms developed in caged oysters deployed 40 days in Quincy Bay, Boston Harbor. Oysters exposed to BRH sediment in the laboratory and in the field accumulated high concentrations of polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), and chlorinated pesticides. Chemical analyses demonstrated high concentrations of PCBs, PAHs, chlorinated pesticides, and heavy metals in BRH sediment. Known genotoxic carcinogens, cocarcinogens, and tumor promoters were present as contaminants. The uptake of parent PAH and PCBs from BRH sediment observed in oysters also occurs in blue mussels (Mytilus edulis). Winter flounder fed BRH-contaminated blue mussels contained xenobiotic chemicals analyzed in mussels. The flounder developed renal and pancreatic neoplasms and hepatotoxic neoplastic precursor lesions, demonstrating trophic transfer of sediment-bound carcinogens up the food chain.« less

Increased sensitivity to the acute effects of MDMA ("ecstasy") in female rats.

PubMed

Palenicek, T; Votava, M; Bubenikova, V; Horacek, J

2005-11-15

Behavioral effects of +/-3,4-methylenedioxymethamphetamine (MDMA, ecstasy) are relatively well described in humans as well as in animals. However, little is known about gender differences to the effects of MDMA. The aim of our study was to evaluate gender differences in stimulant effects of MDMA (2.5, 5.0, and 10.0 mg/kg subcutaneously (s.c.)) in male and female Wistar rats. We have used three behavioral methods (activity cage, open field, and elevated plus-maze) each describing a different pattern of spontaneous behavior. In the activity cage, 30 min after the MDMA administration, horizontal and vertical locomotor activities were registered for a period of 3 min. In the open field test rats were placed into an arena 15 min after drug treatment and locomotor activity was registered for a period of 30 min. Finally, in the elevated plus-maze test, rats were given MDMA 30 min prior to measurements and subsequently they were tested in the maze for a period of 5 min. In our experiments we observed a dose-dependent locomotion-enhancing effect of MDMA both in male and female rats in both locomotor tests. Female rats were more sensitive to the locomotor-stimulating effect than males in both tests, suggesting higher sensitivity to the stimulatory effect of MDMA. Further on, MDMA increased thigmotaxis in female rats in the open field test and decreased "anxious-like" behavior in the elevated plus-maze in both genders. In conclusion, we observed higher sensitivity of females to the locomotor-stimulant effect of MDMA. Increased sensitivity of females to the behavioral effects of MDMA can be explained by increased reactivity of serotonergic and dopaminergic systems.

Photodissociation and caging of HBr and HI molecules on the surface of large rare gas clusters.

PubMed

Baumfalk, R; Nahler, N H; Buck, U

2001-01-01

Photodissociation experiments were carried out at a wavelength of 243 nm for single HBr and HI molecules adsorbed on the surface of large Nen, Arn, Krn and Xen clusters. The average size is about = 130; the size ranges = 62-139 for the system HBr-Arn and = 110-830 for HI-Xen were covered. In this way the dependence of the photodissociation dynamics on both the size and the rare gas host cluster was investigated. The main observable is the kinetic energy distribution of the outgoing H atoms. The key results are that we do not find any size dependence for either system but that we observe a strong dependence on the rare gas clusters. All systems exhibit H atoms with no energy loss that indicate direct cage exit and those with nearly zero energy that are an indication of complete caging. The intensity ratio of caged to uncaged H atoms is largest for Nen, decreases with increasing mass of the cage atoms, and is weakest for Xen. On the basis of accompanying calculations this behaviour is attributed to the large amplitude motion of the light H atom. This leads to direct cage exit and penetration of the atom through the cluster with different energy transfer per collision depending on the rare gas atoms. The differences between HBr and HI molecules are attributed to different surface states, a flat and an encapsulated site.

Screening of melon genotypes for resistance to vegetable leafminer and your phenotypic correlations with colorimetry.

PubMed

Oliveira, Frederico I C DE; Fiege, Leonardo B C; Celin, Elaine F; Innecco, Renato; Nunes, Glauber H S; Aragão, Fernando A S DE

2017-01-01

Melon is one of the most important vegetable crops in the world. With short cycle in a system of phased planting, phytosanitary control is compromised, and a great volume of agricultural chemicals is used to control vegetable leafminer. Genetic control is an ideal alternative to avoid the damage caused by this insect. Thus, the aim of this study was to evaluate Cucumis accessions in regard to resistance to leafminer and correlate the variables analyzed. Fifty-four accessions and four commercial hybrids of melon were tested. The study was divided into two experiments: with and with no choice. The following characteristics were evaluated: with choice, in field - subjective score based on the infestation and the number of mines per leaf; and with no choice, in cage - number of mines per leaf, chlorophyll content, and leaf colorimetry. The results showed variability among the accessions and some genotypes showed favorable results for resistance in both experiments. There was correlation between the two variables in the experiment in the field. The accessions CNPH 11-282, CNPH 06-1047, and CNPH 11-1077 are the most recommended for future breeding programs with aim on introgression of resistance to vegetable leafminer in melon.

A preclinical large animal study on a novel intervertebral fusion cage covered with high porosity titanium sheets with a triple pore structure used for spinal fusion.

PubMed

Yamada, Katsuhisa; Ito, Manabu; Akazawa, Toshiyuki; Murata, Masaru; Yamamoto, Toru; Iwasaki, Norimasa

2015-11-01

To evaluate the osteoconductivity and the bonding strength of the newly developed interbody cage covered with the porous titanium sheet (porous Ti cage) to vertebral bodies in a sheep model. Twelve sheep underwent anterior lumbar interbody fusion at L2-3 and L4-5 using either the new porous Ti cages (Group-P) or conventional Ti cages with autogenous iliac bone (Group-C). The animals were euthanized at 2 or 4 months postoperatively and subjected to radiological, biomechanical, and histological examinations. Computed tomography analyses showed that the ratio of bone contact area in Group-P was significantly increased at 4 months compared with that at 2 months (p = 0.01). Although the ratio of bone contact area in Group-C was significantly higher than Group-P at 2 months (p < 0.001), there was no statistically significant difference between the two groups at 4 months. Biomechanical test showed that there was no significant difference in bonding strength between the two groups at either 2 or 4 months. Histological analyses revealed that the bone apposition ratio increased significantly with time in Group-P (p < 0.001). Although Group-C showed significantly higher bone apposition ratio than Group-P at 2 months (p = 0.001), there was no statistical difference between the two groups at 4 months. There was bone ingrowth into the porous Ti sheet, and bonding capacity of the porous Ti cage to the host bone increased with time. However, the speed of union to the bone with a porous Ti cage was marginally lower than a conventional cage along with an autogenous bone graft. Although it needs further experiment with a larger sample size, the results of the current study suggested that this material could achieve interbody fusion without the need for bone grafts.

Flow cytometer

DOEpatents

Van den Engh, G.

1995-11-07

A Faraday cage is described which encloses the flow chamber of a cytometer. Ground planes associated with each field deflection plate inhibit electric fields from varying the charge on designated events/droplets and further concentrates. They also increase forces applied to a passing charged event for accurate focus while concomitantly inhibiting a potential shock hazard. 4 figs.

Flow cytometer

DOEpatents

van den Engh, Ger

1995-01-01

A Faraday cage enclosing the flow chamber of a cytometer and ground planes associated with each field deflection plate in concert therewith inhibit electric fields from varying the charge on designated events/droplets and further concentrates and increases forces applied to a charged event passing therethrough for accurate focus thereof while concomitantly inhibiting a potential shock hazard.

Structures of cage, prism, and book isomers of water hexamer from broadband rotational spectroscopy.

PubMed

Pérez, Cristóbal; Muckle, Matt T; Zaleski, Daniel P; Seifert, Nathan A; Temelso, Berhane; Shields, George C; Kisiel, Zbigniew; Pate, Brooks H

2012-05-18

Theory predicts the water hexamer to be the smallest water cluster with a three-dimensional hydrogen-bonding network as its minimum energy structure. There are several possible low-energy isomers, and calculations with different methods and basis sets assign them different relative stabilities. Previous experimental work has provided evidence for the cage, book, and cyclic isomers, but no experiment has identified multiple coexisting structures. Here, we report that broadband rotational spectroscopy in a pulsed supersonic expansion unambiguously identifies all three isomers; we determined their oxygen framework structures by means of oxygen-18-substituted water (H(2)(18)O). Relative isomer populations at different expansion conditions establish that the cage isomer is the minimum energy structure. Rotational spectra consistent with predicted heptamer and nonamer structures have also been identified.

The elementary steps of the photodissociation and recombination reactions of iodine molecules enclosed in cages and channels of zeolite crystals: a femtosecond time-resolved study of the geometry effect.

PubMed

Flachenecker, G; Materny, A

2004-03-22

We present femtosecond time-resolved pump-probe experiments on iodine molecules enclosed into well-defined cages and channels of different crystalline SiO2 modifications of zeolites. The new experimental results obtained from iodine in TON (Silica-ZSM-22), FER (Silica-Ferrierit), and MFI (Silicalit-1) porosils are compared with data published earlier on the iodine/DDR (Decadodecasil 3R) porosil system [Flachenecker et al., Phys. Chem. Chem. Phys. 5, 865 (2003)]. A summary of all findings is given. The processes analyzed by means of the ultrafast spectroscopy are the vibrational relaxation as well as the dissociation and recombination reactions, which are caused by the interaction of the photo-excited iodine molecules with the cavity walls of the porosils. A clear dependence of the observed dynamics on the geometry of the surrounding lattice structure can be seen. These measurements are supported by temperature-dependent experiments. Making use of a theoretical model which is based on the classical Langevin equation, an analysis of the geometry-reaction relation is performed. The Brownian dynamics simulations show that in contrast to the vibrational relaxation the predissociation dynamics are independent of the frequency of collisions with the surroundings. From the results obtained in the different surroundings, we conclude that mainly local fields are responsible for the crossing from the bound B state to the repulsive a/a' states of the iodine molecules.

Herbivore effects on productivity vary by guild: cattle increase mean productivity while wildlife reduce variability.

PubMed

Charles, Grace K; Porensky, Lauren M; Riginos, Corinna; Veblen, Kari E; Young, Truman P

2017-01-01

Wild herbivores and livestock share the majority of rangelands worldwide, yet few controlled experiments have addressed their individual, additive, and interactive impacts on ecosystem function. While ungulate herbivores generally reduce standing biomass, their effects on aboveground net primary production (ANPP) can vary by spatial and temporal context, intensity of herbivory, and herbivore identity and species richness. Some evidence indicates that moderate levels of herbivory can stimulate aboveground productivity, but few studies have explicitly tested the relationships among herbivore identity, grazing intensity, and ANPP. We used a long-term exclosure experiment to examine the effects of three groups of wild and domestic ungulate herbivores (megaherbivores, mesoherbivore wildlife, and cattle) on herbaceous productivity in an African savanna. Using both field measurements (productivity cages) and satellite imagery, we measured the effects of different herbivore guilds, separately and in different combinations, on herbaceous productivity across both space and time. Results from both productivity cage measurements and satellite normalized difference vegetation index (NDVI) demonstrated a positive relationship between mean productivity and total ungulate herbivore pressure, driven in particular by the presence of cattle. In contrast, we found that variation in herbaceous productivity across space and time was driven by the presence of wild herbivores (primarily mesoherbivore wildlife), which significantly reduced heterogeneity in ANPP and NDVI across both space and time. Our results indicate that replacing wildlife with cattle (at moderate densities) could lead to similarly productive but more heterogeneous herbaceous plant communities in rangelands. © 2016 by the Ecological Society of America.

Evaluation of Two Compressed Air Foam Systems for Culling Caged Layer Hens.

PubMed

Benson, Eric R; Weiher, Jaclyn A; Alphin, Robert L; Farnell, Morgan; Hougentogler, Daniel P

2018-04-24

Outbreaks of avian influenza (AI) and other highly contagious poultry diseases continue to be a concern for those involved in the poultry industry. In the situation of an outbreak, emergency depopulation of the birds involved is necessary. In this project, two compressed air foam systems (CAFS) were evaluated for mass emergency depopulation of layer hens in a manure belt equipped cage system. In both experiments, a randomized block design was used with multiple commercial layer hens treated with one of three randomly selected depopulation methods: CAFS, CAFS with CO₂ gas, and CO₂ gas. In Experiment 1, a Rowe manufactured CAFS was used, a selection of birds were instrumented, and the time to unconsciousness, brain death, altered terminal cardiac activity and motion cessation were recorded. CAFS with and without CO₂ was faster to unconsciousness, however, the other parameters were not statistically significant. In Experiment 2, a custom Hale based CAFS was used to evaluate the impact of bird age, a selection of birds were instrumented, and the time to motion cessation was recorded. The difference in time to cessation of movement between pullets and spent hens using CAFS was not statistically significant. Both CAFS depopulate caged layers, however, there was no benefit to including CO₂.

A large scale laboratory cage trial of Aedes densonucleosis virus (AeDNV).

PubMed

Wise de Valdez, Megan R; Suchman, Erica L; Carlson, Jonathan O; Black, William C

2010-05-01

Aedes aegypti (L.) (Diptera: Culicidae) the primary vector of dengue viruses (DENV1-4), oviposit in and around human dwellings, including sites difficult to locate, making control of this mosquito challenging. We explored the efficacy and sustainability of Aedes Densonucleosis Virus (AeDNV) as a biocontrol agent for Ae. aegypti in and among oviposition sites in large laboratory cages (> 92 m3) as a prelude to field trials. Select cages were seeded with AeDNV in a single oviposition site (OPS) with unseeded OPSs established at varied distances. Quantitative real-time polymerase chain reaction was used to track dispersal and accumulation of AeDNV among OPSs. All eggs were collected weekly from each cage and counted. We asked: (1) Is AeDNV dispersed over varying distances and can it accumulate and persist in novel OPSs? (2) Are egg densities reduced in AeDNV treated populations? AeDNV was dispersed to and sustained in novel OPSs. Virus accumulation in OPSs was positively correlated with egg densities and proximity to the initial infection source affected the timing of dispersal and maintenance of viral titers. AeDNV did not significantly reduce Ae. aegypti egg densities. The current study documents that adult female Ae. aegypti oviposition behavior leads to successful viral dispersal from treated to novel containers in large-scale cages; however, the AeDNV titers reached were not sufficient to reduce egg densities.

Simulated aerial sprays for field cage evaluation of Beauveria bassiana and Metarhizium brunneum (Ascomycetes: Hypocreales) against Anabrus simplex (Orthoptera: Tettigoniidae) in Montana

USDA-ARS?s Scientific Manuscript database

Field efficacy of the entomopathogenic Ascomycete Beauveria bassiana strain GHA and Metarhizium brunneum strain F52 was evaluated against nymphs of the Mormon cricket, Anabrus simplex. Fungi were applied with a new apparatus that allows simulated aerial sprays to 0.1m2 areas in the field. The Mormon...

Field testing Diorhabda elongata (Coleoptera:Chrysomelidae) from Crete, Greece to assess potential impact to non-target native California plants in the genus Frankenia

USDA-ARS?s Scientific Manuscript database

When laboratory host specificity tests on weed biological control agents produce ambiguous results or are suspected of producing false positives, field cage or open field tests can be utilized in an attempt to determine the true ecological host range of the agent. The leaf beetle Diorhabda elongata ...

Position and Orientation Insensitive Wireless Power Transmission for EnerCage-Homecage System.

PubMed

Jia, Yaoyao; Mirbozorgi, S Abdollah; Wang, Zheyuan; Hsu, Chia-Chun; Madsen, Teresa E; Rainnie, Donald; Ghovanloo, Maysam

2017-10-01

We have developed a new headstage architecture as part of a smart experimental arena, known as the EnerCage-HC2 system, which automatically delivers stimulation and collects behavioral data over extended periods with minimal small animal subject handling or personnel intervention in a standard rodent homecage. Equipped with a four-coil inductive link, the EnerCage-HC2 system wirelessly powers the receiver (Rx) headstage, irrespective of the subject's location or head orientation, eliminating the need for tethering or carrying bulky batteries. On the transmitter (Tx) side, a driver coil, five high-quality (Q) factor segmented resonators at different heights and orientations, and a closed-loop Tx power controller create a homogeneous electromagnetic (EM) field within the homecage 3-D space, and compensate for drops in power transfer efficiency (PTE) due to Rx misalignments. The headstage is equipped with four small slanted resonators, each covering a range of head orientations with respect to the Tx resonators, which direct the EM field toward the load coil at the bottom of the headstage. Moreover, data links based on Wi-Fi, UART, and Bluetooth low energy are utilized to enables remote communication and control of the Rx. The PTE varies within 23.6%-33.3% and 6.7%-10.1% at headstage heights of 8 and 20 cm, respectively, while continuously delivering >40 mW to the Rx electronics even at 90° rotation. As a proof of EnerCage-HC2 functionality in vivo, a previously documented on-demand electrical stimulation of the globus pallidus, eliciting consistent head rotation, is demonstrated in three freely behaving rats.

Pupation Behavior and Predation on Drosophila suzukii (Diptera: Drosophilidae) Pupae in Maine Wild Blueberry Fields.

PubMed

Ballman, Elissa S; Collins, Judith A; Drummond, Francis A

2017-12-05

Drosophila suzukii (Matsumura; Diptera: Drosophilidae) is an invasive vinegar fly and pest of soft fruits in North America, including wild blueberries (Vaccinium angustifolium Aiton) in Maine. Despite its presence in the continental United States for 9 yr, little is known about its natural enemy complex. Here we report the results of a 3-yr study designed to identify naturally-occurring predators in Maine's wild blueberry fields. Experiments were conducted to determine pupation site and pupation depth to understand D. suzukii's predation vulnerability. Predation rates in the field of fully-exposed, caged, and buried pupae were measured. Pitfall traps were deployed to identify the potential predator assemblage, and laboratory experiments were conducted to determine how many pupae were consumed by commonly occurring ground beetle species (Carabidae) and field crickets (Gryllus pennsylvanicus Burmeister). The most commonly collected predators were ants, ground beetles, harvestmen, and field crickets. Significantly more pupae were found to occur in the soil compared to blueberry fruit, with most pupae in the top 0.5 cm layer of soil. Pupal predation rates in the field were high, with higher rates of predation on exposed pupae compared to buried pupae. Laboratory studies revealed that ground beetles and field crickets are likely predators of D. suzukii pupae. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

[Investigations on the effect of an electrostatic field free of residual waves on the motility of the mouse (author's transl)].

PubMed

Fischer, G

1977-08-01

Comparative investigations were carried out concerning the influence on the motility of mice of different electrobioclimatic conditions (electrostatic field with a residual wave component of 1% and a field strength of 4.500 V/m; pure residual wave component: 32 Vs/s, field strength 120 V/m/ss; electrostatic field established by batteries: initial voltage 900 V, field strength 4.500 V/m; shielded from ambient atmospheric electrical fields: damping efficiency at 99%). The Faraday condition represented the control as absolutely objective physical magnitude. All experimental chambers were positioned under Faraday shields. Following a 20 day period of acclimatization to the unaccustomed surroundings for the animals (adaptation period), we established the previously described electrophysical conditions in the cages for a further period of 20 days (experimental period). The lowest values measured during the daily readings were found in the Faraday cage, resp. in the pure electrostatic field, the highest in the DC-field with residual wave component resp. in the residual wave component alone. We draw the following conclusion from the findings: the pure DC-field apparently does not possess those bioclimatologically decisive importance that has been and is being postulated from several sides. Many of the stimtng effects observed and attributed to the electrostatic field are most probably due to the residual wave component resulting from the high-voltage generators employed.

A caged Ab reveals an immediate/instructive effect of BDNF during hippocampal synaptic potentiation

PubMed Central

Kossel, Albrecht H.; Cambridge, Sidney B.; Wagner, Uta; Bonhoeffer, Tobias

2001-01-01

Neurotrophins have been shown to be involved in functional strengthening of central nervous system synapses. Although their general importance in this process is undisputed, it remains unresolved whether neurotrophins are truly mediators of synaptic strengthening or merely important cofactors. To address this question, we have devised a method to inactivate endogenous brain-derived neurotrophic factor (BDNF) with high time resolution by “caging” a function-blocking mAb against BDNF with a photosensitive protecting compound. Different assays were used to show that this inactivation of the Ab is reversible by UV light. Synaptic potentiation after τ-burst stimulation in the CA1 region of acute hippocampal slices was significantly less when applying the unmodified Ab compared with the caged Ab. Importantly, photoactivation of the caged Ab during the time of induction of synaptic enhancement led to a marked decrease in potentiation. Our experiments therefore strengthen the view that endogenous BDNF has fast effects during induction of synaptic plasticity. The results additionally show that caged Abs can provide a tool for precise spatiotemporal control over endogenous protein levels. PMID:11724927

Effect of Male House Mouse Pheromone Components on Behavioral Responses of Mice in Laboratory and Field Experiments.

PubMed

Musso, Antonia E; Gries, Regine; Zhai, Huimin; Takács, Stephen; Gries, Gerhard

2017-03-01

Urine of male house mice, Mus musculus, is known to have primer pheromone effects on the reproductive physiology of female mice. Urine-mediated releaser pheromone effects that trigger certain behavioral responses are much less understood, and no field studies have investigated whether urine deposits by male or female mice, or synthetic mouse pheromone, increase trap captures of mice. In field experiments, we baited traps with bedding soiled with urine and feces of caged female or male mice, and recorded captures of mice in these and in control traps containing clean bedding. Traps baited with female bedding preferentially captured adult males, whereas traps baited with male bedding preferentially captured juvenile and adult females, indicating the presence of male- and female-specific sex pheromones in soiled bedding. Analyses of headspace volatiles emanating from soiled bedding by gas chromatography/mass spectrometry revealed that 3,4-dehydro-exo-brevicomin (DEB) was seven times more prevalent in male bedding and that 2-sec-butyl-4,5-dihydrothiazole (DHT) was male-specific. In a follow-up field experiment, traps baited with DEB and DHT captured 4 times more female mice than corresponding control traps, thus indicating that DEB and DHT are sex attractant pheromone components of house mouse males. Our study provides impetus to identify the sex attractant pheromone of female mice, and to develop synthetic mouse pheromone as a lure to enhance the efficacy of trapping programs for mouse control.

Studies on Charge Variation and Waves in Dusty Plasmas

NASA Astrophysics Data System (ADS)

Kausik, Siddhartha Sankar

Plasma and dust grains are both ubiquitous ingredients of the universe. The interplay between them has opened up a new and fascinating research domain, that of dusty plasmas, which contain macroscopic particles of solid matter besides the usual plasma constituents. The research in dusty plasmas received a major boost in the early eighties with Voyager spacecraft observation on the formation of Saturn rings. Dusty plasmas are defined as partially or fully-ionized gases that contain micron-sized particles of electrically charged solid material, either dielectric or conducting. The physics of dusty plasmas has recently been studied intensively because of its importance for a number of applications in space and laboratory plasmas. This thesis presents the experimental studies on charge variation and waves in dusty plasmas. The experimental observations are carried out in two different experimental devices. Three different sets of experiments are carried out in two different experimental devices. Three different sets of experiments are carried out to study the dust charge variation in a filament discharge argon plasma. The dust grains used in these experiments are grains of silver. In another get of experiment, dust acoustic waves are studied in a de glow discharge argon plasma. Alumina dust grains are sprinkled in this experiment. The diagnostic tools used in these experiments are Langmuir probe and Faraday cup. The instruments used in these experiments are electrometer, He-Ne laser and charge coupled device (CCD) camera. Langmuir probe is used to measure plasma parameters, while Faraday cup and electrometer are used to measure very low current (~pA) carried by a collimated dust beam. He-Ne laser illuminates the dust grains and CCD camera is used to capture the images of dust acoustic waves. Silver dust grains are produced in the dust chamber by gas-evaporation technique. Due to differential pressure maintained between the dust and plasma chambers, the dust grains move upward in the form of a collimated beam. Argon plasma is produced in an experimental setup consisting of a dust chamber, a plasma chamber and a diagnostic chamber (also called deflection chamber) by striking a discharge between incandescent tungsten filaments and the magnetic cage, which is grounded. Plasma thus produced is confined by a full line cusped magnetic field confinement system consisting of a cylindrically shaped cage made up of stainless steel channels filled up with cube shaped having 1.2 kG field strength at its surface.

Nonhost status of commercial Persea americana 'Hass' to Anastrepha ludens, Anastrepha obliqua, Anastrepha serpentina, and Anastrepha striata (Diptera: Tephritidae) in Mexico.

PubMed

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

2004-04-01

The objective of this study was to determine the host status in Mexico of commercially cultivated and marketed avocado, Persea americana (Mill.), 'Hass' to Anastrepha ludens (Loew), Anastrepha obliqua (Macquart), Anastrepha serpentina (Wiedemann), and Anastrepha striata (Schiner) (Diptera: Tephritidae). Experiments in Michoacán, Mexico, were carried out in six orchards located at three altitudes above sea level during two times (August-October 2001 and April-June 2002). They included choice ('Hass' avocado plus natural host) and no-choice foraging behavior tests on trees under field cages; no-choice, forced infestation trials on caged, fruit-bearing branches in the field, and with individual fruit under laboratory conditions; infestation trials using 'Hass' avocados left unprotected over 1 and 7 d on the ground of orchards; studies to ascertain depth of oviposition and determine egg hatchability; and experiments to determine susceptibility by using time elapsed since removal of fruit from tree as the experimental variable. We trapped adult Anastrepha (n = 7,936) in all orchards and dissected fruit (n = 7,695) from orchards and packing houses (n = 1,620) in search of eggs or larvae. Most (96.7%) A. ludens, A. obliqua, A. striata, and A. serpentina adults were captured in low-elevation orchards. No eggs or larvae were detected in any of the fruit from foraging behavior studies or dissected fruit from orchards or packing houses. Of 5,200 mature, intact fruit on trees in the field forcibly exposed to no-choice female oviposition activity (five females/fruit), we only found four fruit infested by A. ludens but no adults emerged. 'Hass' avocados only became marginally susceptible to attack by A. ludens (but not A. obliqua, A. serpentina, and A. striata) 24 h after being removed from the tree. Fruit placed on the ground in orchards (n = 3,600) were occasionally infested by Neosilba batesi (Curran) (Diptera: Lonchaeidae), a decomposer, but not Anastrepha spp. Based on our results, commercially cultivated and marketed P. americana 'Hass' should not be considered a natural host of A. ludens, A. obliqua, A. striata, and A. serpentina in Mexico.

Investigating short-term exposure to electromagnetic fields on reproductive capacity of invertebrates in the field situation.

PubMed

Vijver, Martina G; Bolte, John F B; Evans, Tracy R; Tamis, Wil L M; Peijnenburg, Willie J G M; Musters, C J M; de Snoo, Geert R

2014-01-01

Organisms are exposed to electromagnetic fields from the introduction of wireless networks that send information all over the world. In this study we examined the impact of exposure to the fields from mobile phone base stations (GSM 900 MHz) on the reproductive capacity of small, virgin, invertebrates. A field experiment was performed exposing four different invertebrate species at different distances from a radiofrequency electromagnetic fields (RF EMF) transmitter for a 48-h period. The control groups were isolated from EMF exposure by use of Faraday cages. The response variables as measured in the laboratory were fecundity and number of offspring. Results showed that distance was not an adequate proxy to explain dose-response regressions. No significant impact of the exposure matrices, measures of central tendency and temporal variability of EMF, on reproductive endpoints was found. Finding no impact on reproductive capacity does not fully exclude the existence of EMF impact, since mechanistically models hypothesizing non-thermal-induced biological effects from RF exposure are still to be developed. The exposure to RF EMF is ubiquitous and is still increasing rapidly over large areas. We plea for more attention toward the possible impacts of EMF on biodiversity.

Unconventional superconductivity in Y5Rh6Sn18 probed by muon spin relaxation

PubMed Central

Bhattacharyya, Amitava; Adroja, Devashibhai; Kase, Naoki; Hillier, Adrian; Akimitsu, Jun; Strydom, Andre

2015-01-01

Conventional superconductors are robust diamagnets that expel magnetic fields through the Meissner effect. It would therefore be unexpected if a superconducting ground state would support spontaneous magnetics fields. Such broken time-reversal symmetry states have been suggested for the high—temperature superconductors, but their identification remains experimentally controversial. We present magnetization, heat capacity, zero field and transverse field muon spin relaxation experiments on the recently discovered caged type superconductor Y5Rh6Sn18 ( TC= 3.0 K). The electronic heat capacity of Y5Rh6Sn18 shows a T3 dependence below Tc indicating an anisotropic superconducting gap with a point node. This result is in sharp contrast to that observed in the isostructural Lu5Rh6Sn18 which is a strong coupling s—wave superconductor. The temperature dependence of the deduced superfluid in density Y5Rh6Sn18 is consistent with a BCS s—wave gap function, while the zero-field muon spin relaxation measurements strongly evidences unconventional superconductivity through a spontaneous appearance of an internal magnetic field below the superconducting transition temperature, signifying that the superconducting state is categorized by the broken time-reversal symmetry. PMID:26286229

Cytoplasmic Incompatibility as a Means of Controlling Culex pipiens quinquefasciatus Mosquito in the Islands of the South-Western Indian Ocean

PubMed Central

Atyame, Célestine M.; Pasteur, Nicole; Dumas, Emilie; Tortosa, Pablo; Tantely, Michaël Luciano; Pocquet, Nicolas; Licciardi, Séverine; Bheecarry, Ambicadutt; Zumbo, Betty; Weill, Mylène; Duron, Olivier

2011-01-01

The use of the bacterium Wolbachia is an attractive alternative method to control vector populations. In mosquitoes, as in members of the Culex pipiens complex, Wolbachia induces a form of embryonic lethality called cytoplasmic incompatibility, a sperm-egg incompatibility occurring when infected males mate either with uninfected females or with females infected with incompatible Wolbachia strain(s). Here we explore the feasibility of the Incompatible Insect Technique (IIT), a species-specific control approach in which field females are sterilized by inundative releases of incompatible males. We show that the Wolbachia wPip(Is) strain, naturally infecting Cx. p. pipiens mosquitoes from Turkey, is a good candidate to control Cx. p. quinquefasciatus populations on four islands of the south-western Indian Ocean (La Réunion, Mauritius, Grande Glorieuse and Mayotte). The wPip(Is) strain was introduced into the nuclear background of Cx. p. quinquefasciatus mosquitoes from La Réunion, leading to the LR[wPip(Is)] line. Total embryonic lethality was observed in crosses between LR[wPip(Is)] males and all tested field females from the four islands. Interestingly, most crosses involving LR[wPip(Is)] females and field males were also incompatible, which is expected to reduce the impact of any accidental release of LR[wPip(Is)] females. Cage experiments demonstrate that LR[wPip(Is)] males are equally competitive with La Réunion males resulting in demographic crash when LR[wPip(Is)] males were introduced into La Réunion laboratory cages. These results, together with the geographic isolation of the four south-western Indian Ocean islands and their limited land area, support the feasibility of an IIT program using LR[wPip(Is)] males and stimulate the implementation of field tests for a Cx. p. quinquefasciatus control strategy on these islands. PMID:22206033

Comparison of stochastic optimization methods for all-atom folding of the Trp-Cage protein.

PubMed

Schug, Alexander; Herges, Thomas; Verma, Abhinav; Lee, Kyu Hwan; Wenzel, Wolfgang

2005-12-09

The performances of three different stochastic optimization methods for all-atom protein structure prediction are investigated and compared. We use the recently developed all-atom free-energy force field (PFF01), which was demonstrated to correctly predict the native conformation of several proteins as the global optimum of the free energy surface. The trp-cage protein (PDB-code 1L2Y) is folded with the stochastic tunneling method, a modified parallel tempering method, and the basin-hopping technique. All the methods correctly identify the native conformation, and their relative efficiency is discussed.

Biomechanical Analysis of Porous Additive Manufactured Cages for Lateral Lumbar Interbody Fusion: A Finite Element Analysis.

PubMed

Zhang, Zhenjun; Li, Hui; Fogel, Guy R; Liao, Zhenhua; Li, Yang; Liu, Weiqiang

2018-03-01

A porous additive manufactured (AM) cage may provide stability similar to that of traditional solid cages and may be beneficial to bone ingrowth. The biomechanical influence of various porous cages on stability, subsidence, stresses in cage, and facet contact force has not been fully described. The purpose of this study was to verify biomechanical effects of porous AM cages. The surgical finite element models with various cages were constructed. The partially porous titanium (PPT) cages and fully porous titanium (FPT) cages were applied. The mechanical parameters of porous materials were obtained by mechanical test. Then the porous AM cages were compared with solid titanium (TI) cage and solid polyetheretherketone (PEEK) cage. The 4 motion modes were simulated. Range of motion (ROM), cage stress, end plate stress, and facet joint force (FJF) were compared. For all the surgical models, ROM decreased by >90%. Compared with TI and PPT cages, PEEK and FPT cages substantially reduced the maximum stresses in cage and end plate in all motion modes. Compared with PEEK cages, the stresses in cage and end plate for FPT cages decreased, whereas the ROM increased. Comparing FPT cages, the stresses in cage and end plate decreased with increasing porosity, whereas ROM increased with increasing porosity. After interbody fusion, FJF was substantially reduced in all motion modes except for flexion. Fully porous cages may offer an alternative to solid PEEK cages in lateral lumbar interbody fusion. However, it may be prudent to further increase the porosity of the cage. Copyright © 2017 Elsevier Inc. All rights reserved.

Predation of intertidal infauna on juveniles of the bivalve Macoma balthica

NASA Astrophysics Data System (ADS)

Hiddink, J. G.; ter Hofstede, R.; Wolff, W. J.

2002-03-01

Juveniles of the bivalve Macoma balthica live on tidal flats in the Wadden Sea. This study examined the interaction of Macoma with the infaunal polychaetes Arenicola marina and Nereis diversicolor and the gastropod Retusa obtusa. The distribution of M. balthica spat on the flats, shortly after settlement in April, showed a positive correlation with the Arenicola distribution and a negative correlation with Nereis distribution. There were no locations where Macoma spat and Retusa occurred together. In August, Macoma spat had grown too large for predation by intertidal infauna. Small individuals of Macoma spat were found in stomachs of Arenicola (0.14 worm -1) and Nereis (0.05 worm -1). Laboratory experiments showed that Nereis and Retusa could reduce Macoma spat abundance, both in the absence and presence of sediment and alternative prey. Arenicola reduced the abundance of small Macoma (<1 mm) in sediment without, but not with, alternative prey. In field experiments, we manipulated the density of Arenicola in 0.25-1 m 2 plots and of Nereis in 0.03 m 2 cages and examined the effect on Macoma density several weeks later. We found a significant negative relation between densities of polychaetes and Macoma spat for both polychaete species in these experimental plots. Peculiarly, we found a significant positive relation between manipulated Nereis density and adult Macoma density in the cages; we cannot explain this. Consumption rates, calculated both from stomach contents and from field experiments, were 45 to 102 Macoma m -2 d -1 for Arenicola and 5 to 116 Macoma m -2 d -1 for Nereis. These values are higher than recorded consumption rates by epibenthic predators in the same area. Nevertheless, between-year differences in year-class strength could not be explained by differential abundance of these polychaetes. In conclusion, Arenicola and Nereis had a negative effect on the abundance of Macoma <1.5 mm, which was at least partly caused by direct consumption. Retusa obtusa can eat juvenile Macoma, but probably did not so in the study area, because there were no locations where Retusa and Macoma spat occurred together in the period that Macoma was <2 mm.

Assessing mouse behaviour throughout the light/dark cycle using automated in-cage analysis tools.

PubMed

Bains, Rasneer S; Wells, Sara; Sillito, Rowland R; Armstrong, J Douglas; Cater, Heather L; Banks, Gareth; Nolan, Patrick M

2018-04-15

An important factor in reducing variability in mouse test outcomes has been to develop assays that can be used for continuous automated home cage assessment. Our experience has shown that this has been most evidenced in long-term assessment of wheel-running activity in mice. Historically, wheel-running in mice and other rodents have been used as a robust assay to determine, with precision, the inherent period of circadian rhythms in mice. Furthermore, this assay has been instrumental in dissecting the molecular genetic basis of mammalian circadian rhythms. In teasing out the elements of this test that have determined its robustness - automated assessment of an unforced behaviour in the home cage over long time intervals - we and others have been investigating whether similar test apparatus could be used to accurately discriminate differences in distinct behavioural parameters in mice. Firstly, using these systems, we explored behaviours in a number of mouse inbred strains to determine whether we could extract biologically meaningful differences. Secondly, we tested a number of relevant mutant lines to determine how discriminative these parameters were. Our findings show that, when compared to conventional out-of-cage phenotyping, a far deeper understanding of mouse mutant phenotype can be established by monitoring behaviour in the home cage over one or more light:dark cycles. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Marine environmental impact assessment of abalone, Haliotis discus hannai, cage farm in Wan-do, Republic of Korea

NASA Astrophysics Data System (ADS)

Oh, Hyun-Taik; Jung, Rae-Hong; Cho, Yoon-Sik; Hwang, Dong-Woon; Yi, Yong-Min

2015-12-01

To assess the marine environmental impacts of abalone, Haliotis discus hannai, cage farms in Wan-do, we monitored the benthic environment on top of the sediment underneath cage farm stations and reference stations. We applied two methods for this assessment. One was the A- and B-investigation of the MOM system (Modeling-On fish farm-Monitoring) developed in Norway. The other was a general environmental monitoring method which is widely used. In this study, we found benthic animals in all samples that belonged to condition 1 which were based on group 1(presence of macrofauna) of the B-investigation method. The values of redox potential (group 2-pH, redox potential) in all samples were above +65 mV belonging to condition 1. Based on sensory results (group 3-gas, color, odor, thickness of deposits), five out of seven experiment samples showed condition 1 while stations 2 and 7 showed condition 2, which have been cultured for 10 years in semi-closed waters. As group 2 takes precedence over group 3, the level of the conditions for B-investigation results consequently showed condition 1 in all stations. We found that pollutants and trace metals in the sediment underneath cage farms were lower than the pollution standard. This led us to conclude that the environmental impacts of the cage farms in this study were not significant.

Evaluation of transmission risks associated with in vivo replication of several high containment pathogens in a biosafety level 4 laboratory

PubMed Central

Alimonti, Judie; Leung, Anders; Jones, Shane; Gren, Jason; Qiu, Xiangguo; Fernando, Lisa; Balcewich, Brittany; Wong, Gary; Ströher, Ute; Grolla, Allen; Strong, James; Kobinger, Gary

2014-01-01

Containment level 4 (CL4) laboratories studying biosafety level 4 viruses are under strict regulations to conduct nonhuman primate (NHP) studies in compliance of both animal welfare and biosafety requirements. NHPs housed in open-barred cages raise concerns about cross-contamination between animals, and accidental exposure of personnel to infectious materials. To address these concerns, two NHP experiments were performed. One examined the simultaneous infection of 6 groups of NHPs with 6 different viruses (Machupo, Junin, Rift Valley Fever, Crimean-Congo Hemorrhagic Fever, Nipah and Hendra viruses). Washing personnel between handling each NHP group, floor to ceiling biobubble with HEPA filter, and plexiglass between cages were employed for partial primary containment. The second experiment employed no primary containment around open barred cages with Ebola virus infected NHPs 0.3 meters from naïve NHPs. Viral antigen-specific ELISAs, qRT-PCR and TCID50 infectious assays were utilized to determine antibody levels and viral loads. No transmission of virus to neighbouring NHPs was observed suggesting limited containment protocols are sufficient for multi-viral CL4 experiments within one room. The results support the concept that Ebola virus infection is self-contained in NHPs infected intramuscularly, at least in the present experimental conditions, and is not transmitted to naïve NHPs via an airborne route. PMID:25059478

Evaluation of transmission risks associated with in vivo replication of several high containment pathogens in a biosafety level 4 laboratory.

PubMed

Alimonti, Judie; Leung, Anders; Jones, Shane; Gren, Jason; Qiu, Xiangguo; Fernando, Lisa; Balcewich, Brittany; Wong, Gary; Ströher, Ute; Grolla, Allen; Strong, James; Kobinger, Gary

2014-07-25

Containment level 4 (CL4) laboratories studying biosafety level 4 viruses are under strict regulations to conduct nonhuman primate (NHP) studies in compliance of both animal welfare and biosafety requirements. NHPs housed in open-barred cages raise concerns about cross-contamination between animals, and accidental exposure of personnel to infectious materials. To address these concerns, two NHP experiments were performed. One examined the simultaneous infection of 6 groups of NHPs with 6 different viruses (Machupo, Junin, Rift Valley Fever, Crimean-Congo Hemorrhagic Fever, Nipah and Hendra viruses). Washing personnel between handling each NHP group, floor to ceiling biobubble with HEPA filter, and plexiglass between cages were employed for partial primary containment. The second experiment employed no primary containment around open barred cages with Ebola virus infected NHPs 0.3 meters from naïve NHPs. Viral antigen-specific ELISAs, qRT-PCR and TCID50 infectious assays were utilized to determine antibody levels and viral loads. No transmission of virus to neighbouring NHPs was observed suggesting limited containment protocols are sufficient for multi-viral CL4 experiments within one room. The results support the concept that Ebola virus infection is self-contained in NHPs infected intramuscularly, at least in the present experimental conditions, and is not transmitted to naïve NHPs via an airborne route.

Furnished Cage System and Hen Well-Being: Comparative Effects of Furnished Cages and Battery Cages on Behavioral Exhibitions in White Leghorn Chickens

USDA-ARS?s Scientific Manuscript database

The battery cage system is being banned in the European Union before or by 2012; and the furnished cage system will be the only cage system allowed after 2012. This study was conducted to examine the different effects of caging systems, furnished cages vs. battery cages, on bird behaviors. One hundr...

Porous concrete block as an environmental enrichment device increases activity of laying hens in cages.

PubMed

Holcman, A; Gorjanc, G; Stuhec, I

2008-09-01

The purpose of this study was to consider the influence of simple and cheap environmental enrichment such as porous concrete on the behavior of laying hens in conventional cages. Forty brown laying hens were housed in individual wire mesh cages: 20 in experimental cages with porous concrete block provided for pecking and 20 in a control group without concrete block provided. Porous concrete block (5 cm length x 5 cm width x 5 cm height) was mounted on the side wall at the height of the hen's head. Behavior was studied from 42 to 48 wk of age. A group of 8 hens was filmed for 24 h, and the camera was moved each day so that all 40 hens were recorded over 5 d each wk. Videotaping was performed in wk 1, 3, 5, and 7 of the experiment. States (long-term behavior) were observed with 5-min interval recording (feeding, preening, resting, and remaining inactive), whereas events (short-term activities) were observed with instantaneous recording (drinking, pecking concrete, pecking neighbors, pecking cage, and attempting to escape). Data were analyzed with generalized linear mixed model with binomial distribution for states, and Poisson distribution for events. Monte Carlo Markov Chain methods were used to estimate model parameters. Because posterior distributions of quantities of interest were skewed, medians and standard errors are reported. Hens in experimental cages were more active in long-term behavior than controls (64.9 +/- 1.9 and 59.3 +/- 1.9% of the light period, respectively). Correspondingly, hens in the control group showed more long-term inactivity. In addition to pecking the porous concrete block, hens in experimental cages also showed other short-term activities with greater frequency (4.10 +/- 0.31 and 3.51 +/- 0.25 events per h, respectively). Our hypothesis that hens in enriched cages would have a greater level of activity was confirmed. Provision of a piece of porous concrete block as a pecking substrate enriched the environment of the birds at negligible cost.

The transmission of stress to grafted bone inside a titanium mesh cage used in anterior column reconstruction after total spondylectomy: a finite-element analysis.

PubMed

Akamaru, Tomoyuki; Kawahara, Norio; Sakamoto, Jiro; Yoshida, Akira; Murakami, Hideki; Hato, Taizo; Awamori, Serina; Oda, Juhachi; Tomita, Katsuro

2005-12-15

A finite-element study of posterior alone or anterior/posterior combined instrumentation following total spondylectomy and replacement with a titanium mesh cage used as an anterior strut. To compare the effect of posterior instrumentation versus anterior/posterior instrumentation on transmission of the stress to grafted bone inside a titanium mesh cage following total spondylectomy. The most recent reconstruction techniques following total spondylectomy for malignant spinal tumor include a titanium mesh cage filled with autologous bone as an anterior strut. The need for additional anterior instrumentation with posterior pedicle screws and rods is controversial. Transmission of the mechanical stress to grafted bone inside a titanium mesh cage is important for fusion and remodeling. To our knowledge, there are no published reports comparing the load-sharing properties of the different reconstruction methods following total spondylectomy. A 3-dimensional finite-element model of the reconstructed spine (T10-L4) following total spondylectomy at T12 was constructed. A Harms titanium mesh cage (DePuy Spine, Raynham, MA) was positioned as an anterior replacement, and 3 types of the reconstruction methods were compared: (1) multilevel posterior instrumentation (MPI) (i.e., posterior pedicle screws and rods at T10-L2 without anterior instrumentation); (2) MPI with anterior instrumentation (MPAI) (i.e., MPAI [Kaneda SR; DePuy Spine] at T11-L1); and (3) short posterior and anterior instrumentation (SPAI) (i.e., posterior pedicle screws and rods with anterior instrumentation at T11-L1). The mechanical energy stress distribution exerted inside the titanium mesh cage was evaluated and compared by finite-element analysis for the 3 different reconstruction methods. Simulated forces were applied to give axial compression, flexion, extension, and lateral bending. In flexion mode, the energy stress distribution in MPI was higher than 3.0 x 10 MPa in 73.0% of the total volume inside the titanium mesh cage, while 38.0% in MPAI, and 43.3% in SPAI. In axial compression and extension modes, there were no remarkable differences for each reconstruction method. In left-bending mode, there was little stress energy in the cancellous bone inside the titanium mesh cage in MPAI and SPAI. This experiment shows that from the viewpoint of stress shielding, the reconstruction method, using additional anterior instrumentation with posterior pedicle screws (MPAI and SPAI), stress shields the cancellous bone inside the titanium mesh cage to a higher degree than does the system using posterior pedicle screw fixation alone (MPI). Thus, a reconstruction method with no anterior fixation should be better at allowing stress for remodeling of the bone graft inside the titanium mesh cage.

The polymethyl methacrylate cervical cage for treatment of cervical disk disease Part III. Biomechanical properties.

PubMed

Chen, Jyi-Feng; Lee, Shih-Tseng

2006-10-01

In a previous article, we used the PMMA cervical cage in the treatment of single-level cervical disk disease and the preliminary clinical results were satisfactory. However, the mechanical properties of the PMMA cage were not clear. Therefore, we designed a comparative in vitro biomechanical study to determine the mechanical properties of the PMMA cage. The PMMA cervical cage and the Solis PEEK cervical cage were compressed in a materials testing machine to determine the mechanical properties. The compressive yield strength of the PMMA cage (7030 +/- 637 N) was less than that of the Solis polymer cervical cage (8100 +/- 572 N). The ultimate compressive strength of the PMMA cage (8160 +/- 724 N) was less than that of the Solis cage (9100 +/- 634 N). The stiffness of the PMMA cervical cage (8106 +/- 817 N/mm) was greater than that of the Solis cage (6486 +/- 530 N/mm). The elastic modulus of the PMMA cage (623 +/- 57 MPa) was greater than that of the Solis cage (510 +/- 42 MPa). The elongation of PMMA cage (43.5 +/- 5.7%) was larger than that of the Solis cage (36.1 +/- 4.3%). Although the compressive yield strength and ultimate compressive strength of the PMMA cervical cage were less than those of the Solis polymer cage, the mechanical properties are better than those of the cervical vertebral body. The PMMA cage is strong and safe for use as a spacer for cervical interbody fusion. Compared with other cage materials, the PMMA cage has many advantages and no obvious failings at present. However, the PMMA cervical cage warrants further long-term clinical study.

Evidence-based severity assessment: Impact of repeated versus single open-field testing on welfare in C57BL/6J mice.

PubMed

Bodden, Carina; Siestrup, Sophie; Palme, Rupert; Kaiser, Sylvia; Sachser, Norbert; Richter, S Helene

2018-01-15

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, laboratory mice (Mus musculus f. domestica) 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.

Probing Surface Electric Field Noise with a Single Ion

DTIC Science & Technology

2013-07-30

potentials is housed inside a Faraday cage providing more than 40 dB of attenuation for electromagnetic fields in the range of frequencies between 200...and measuring the ion quantum state [16]. Thus, by measuring the effect of electric field noise on the motional quantum state of the ion, one can probe...understand these effects . In summary, we have probed the electric field noise near an aluminum-copper surface at room temperature using a single trapped ion

Columnar transmitter based wireless power delivery system for implantable device in freely moving animals.

PubMed

Eom, Kyungsik; Jeong, Joonsoo; Lee, Tae Hyung; Lee, Sung Eun; Jun, Sang Bum; Kim, Sung June

2013-01-01

A wireless power delivery system is developed to deliver electrical power to the neuroprosthetic devices that are implanted into animals freely moving inside the cage. The wireless powering cage is designed for long-term animal experiments without cumbersome wires for power supply or the replacement of batteries. In the present study, we propose a novel wireless power transmission system using resonator-based inductive links to increase power efficiency and to minimize the efficiency variations. A columnar transmitter coil is proposed to provide lateral uniformity of power efficiency. Using this columnar transmitter coil, only 7.2% efficiency fluctuation occurs from the maximum transmission efficiency of 25.9%. A flexible polymer-based planar type receiver coil is fabricated and assembled with a neural stimulator and an electrode. Using the designed columnar transmitter coil, the implantable device successfully operates while it moves freely inside the cage.

Rotational Brownian Dynamics simulations of clathrin cage formation

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

Ilie, Ioana M.; Briels, Wim J.; MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede

2014-08-14

The self-assembly of nearly rigid proteins into ordered aggregates is well suited for modeling by the patchy particle approach. Patchy particles are traditionally simulated using Monte Carlo methods, to study the phase diagram, while Brownian Dynamics simulations would reveal insights into the assembly dynamics. However, Brownian Dynamics of rotating anisotropic particles gives rise to a number of complications not encountered in translational Brownian Dynamics. We thoroughly test the Rotational Brownian Dynamics scheme proposed by Naess and Elsgaeter [Macromol. Theory Simul. 13, 419 (2004); Naess and Elsgaeter Macromol. Theory Simul. 14, 300 (2005)], confirming its validity. We then apply the algorithmmore » to simulate a patchy particle model of clathrin, a three-legged protein involved in vesicle production from lipid membranes during endocytosis. Using this algorithm we recover time scales for cage assembly comparable to those from experiments. We also briefly discuss the undulatory dynamics of the polyhedral cage.« less

Femtosecond Laser Microfabrication of an Integrated Device for Optical Release and Sensing of Bioactive Compounds.

PubMed

Ghezzi, Diego; Vazquez, Rebeca Martinez; Osellame, Roberto; Valtorta, Flavia; Pedrocchi, Alessandra; Valle, Giuseppe Della; Ramponi, Roberta; Ferrigno, Giancarlo; Cerullo, Giulio

2008-10-23

Flash photolysis of caged compounds is one of the most powerful approaches to investigate the dynamic response of living cells. Monolithically integrated devices suitable for optical uncaging are in great demand since they greatly simplify the experiments and allow their automation. Here we demonstrate the fabrication of an integrated bio-photonic device for the optical release of caged compounds. Such a device is fabricated using femtosecond laser micromachining of a glass substrate. More in detail, femtosecond lasers are used both to cut the substrate in order to create a pit for cell growth and to inscribe optical waveguides for spatially selective uncaging of the compounds present in the culture medium. The operation of this monolithic bio-photonic device is tested using both free and caged fluorescent compounds to probe its capability of multipoint release and optical sensing. Application of this device to the study of neuronal network activity can be envisaged.

Proof of concept of a novel SMA cage actuator

NASA Astrophysics Data System (ADS)

Deyer, Christopher W.; Brei, Diann E.

2001-06-01

Numerous industrial applications that currently utilize expensive solenoids or slow wax motors are good candidates for smart material actuation. Many of these applications require millimeter-scale displacement and low cost; thereby, eliminating piezoelectric technologies. Fortunately, there is a subset of these applications that can tolerate the slower response of shape memory alloys. This paper details a proof-of-concept study of a novel SMA cage actuator intended for proportional braking in commercial appliances. The chosen actuator architecture consists of a SMA wire cage enclosing a return spring. To develop an understanding of the influences of key design parameters on the actuator response time and displacement amplitude, a half-factorial 25 Design of Experiment (DOE) study was conducted utilizing eight differently configured prototypes. The DOE results guided the selection of the design parameters for the final proof-of-concept actuator. This actuator was built and experimentally characterized for stroke, proportional control and response time.

Modelling of current loads on aquaculture net cages

NASA Astrophysics Data System (ADS)

Kristiansen, Trygve; Faltinsen, Odd M.

2012-10-01

In this paper we propose and discuss a screen type of force model for the viscous hydrodynamic load on nets. The screen model assumes that the net is divided into a number of flat net panels, or screens. It may thus be applied to any kind of net geometry. In this paper we focus on circular net cages for fish farms. The net structure itself is modelled by an existing truss model. The net shape is solved for in a time-stepping procedure that involves solving a linear system of equations for the unknown tensions at each time step. We present comparisons to experiments with circular net cages in steady current, and discuss the sensitivity of the numerical results to a set of chosen parameters. Satisfactory agreement between experimental and numerical prediction of drag and lift as function of the solidity ratio of the net and the current velocity is documented.

[Phosphorus magnetic resonance spectroscopy: Brain pathologies applications].

PubMed

Menuel, C; Guillevin, R; Costalat, R; Perrin, M; Sahli-Amor, M; Martin-Duverneuil, N; Chiras, J

2010-05-01

Until recent years, brain applications of (31)P magnetic resonance spectroscopy were poor. Arising of clinical high field strength magnets (three Tesla) as well as dedicated brain coils (eg: bird cage), using specific and useful sequences providing appropriate spatial localisation and signal to noise ratio brought highlights on multinuclear spectroscopy. Better understanding of brain metabolism emphasizes the role of phosphoenergetic compounds and its potential issues in tumoral, metabolic and degenerative diseases. In the present paper, we report 1 year of experience and preliminary results for 40 patients as well as review of the literature. By successive in vivo determination and quantitation of numerous metabolites it allows, multinuclear spectroscopy may provide additional information to biomathematical models of brain metabolism. Copyright 2009. Published by Elsevier Masson SAS.

A stimulation method using odors suitable for PET and fMRI studies with recording of physiological and behavioral signals.

PubMed

Vigouroux, M; Bertrand, B; Farget, V; Plailly, J; Royet, J P

2005-03-15

A design for a semi-automatic olfactometric system is described for PET and fMRI experiments. The olfactometer presents several advantages because it enables the use of an 'infinite' number of odorants and the synchronization of stimuli with breathing. These advantages mean that the subject is recorded while breathing normally during olfactory judgment tasks. In addition, the design includes a system for recording the behavioral (rating scale) and physiological (breathing, electrodermal reaction (ED), plethysmography (PL)) signals given by the subject. Both systems present the advantage of being compatible with fMRI magnetic fields since no ferrous material is used in the Faraday cage and signals are transmitted via an optical transmission interface to an acquisition system.

Electrostatic capacitance and Faraday cage behavior of carbon nanotube forests

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

Ya'akobovitz, A.; Department of Mechanical Engineering, Faculty of Engineering Sciences, Ben-Gurion University, Beer-Sheva; Bedewy, M.

2015-02-02

Understanding of the electrostatic properties of carbon nanotube (CNT) forests is essential to enable their integration in microelectronic and micromechanical devices. In this study, we sought to understand how the hierarchical geometry and morphology of CNT forests determines their capacitance. First, we find that at small gaps, solid micropillars have greater capacitance, yet at larger gaps the capacitance of the CNT forests is greater. The surface area of the CNT forest accessible to the electrostatic field was extracted by analysis of the measured capacitance, and, by relating the capacitance to the average density of CNTs in the forest, we findmore » that the penetration depth of the electrostatic field is on the order of several microns. Therefore, CNT forests can behave as a miniature Faraday cage. The unique electrostatic properties of CNT forests could therefore enable their use as long-range proximity sensors and as shielding elements for miniature electronic devices.« less

Electrostatic capacitance and Faraday cage behavior of carbon nanotube forests

NASA Astrophysics Data System (ADS)

Ya'akobovitz, A.; Bedewy, M.; Hart, A. J.

2015-02-01

Understanding of the electrostatic properties of carbon nanotube (CNT) forests is essential to enable their integration in microelectronic and micromechanical devices. In this study, we sought to understand how the hierarchical geometry and morphology of CNT forests determines their capacitance. First, we find that at small gaps, solid micropillars have greater capacitance, yet at larger gaps the capacitance of the CNT forests is greater. The surface area of the CNT forest accessible to the electrostatic field was extracted by analysis of the measured capacitance, and, by relating the capacitance to the average density of CNTs in the forest, we find that the penetration depth of the electrostatic field is on the order of several microns. Therefore, CNT forests can behave as a miniature Faraday cage. The unique electrostatic properties of CNT forests could therefore enable their use as long-range proximity sensors and as shielding elements for miniature electronic devices.

Virus-Based Nanoparticles of Simian Virus 40 in the Field of Nanobiotechnology.

PubMed

Zhang, Wenjing; Zhang, Xian-En; Li, Feng

2017-12-26

Biomolecular nanostructures derived from living organisms, such as protein cages, fibers, and layers are drawing increasing interests as natural biomaterials. The virus-based nanoparticles (VNPs) of simian virus 40 (SV40), with a cage-like structure assembled from the major capsid protein of SV40, have been developed as a platform for nanobiotechnology in the recent decade. Foreign nanomaterials (e.g., quantum dots (QDs) and gold nanoparticles (AuNPs)) can be positioned in the inner cavity or on the outer surface of SV40 VNPs, through self-assembly by engineering the nanoparticle (NP)-protein interfacial interactions. Construction of these hybrid nanostructures has enabled integration of different functionalities. This review briefly summarizes the applications of SV40 VNPs in this multidisciplinary field, including NP encapsulation, templated assembly of nanoarchitectures, nanophotonics, and fluorescence imaging. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Relatively brief environmental enrichment aids recovery of learning capacity and alters brain measures after postweaning brain lesions in rats

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

Will, B.E.; Rosenzweig, M.R.; Bennett, E.L.

1977-01-01

Enriched postlesion experience aided in overcoming effects of simultaneous bilateral cerebral lesions made at 30 days of age in one experiment with inbred Fischer rats and in a second experiment with the Berkeley S/sub 1/ strain. The lesions were directed to the occipital cortex, but in most cases there was also some impairment of the hippocampus. For 60 days after operations, half of the rats lived in small individual cages and half lived in groups in large enriched-environment cages. They were then pretrained and tested on the standard 12 Hebb-Williams problems. Daily injections of methamphetamine (vs. saline) during the periodmore » of differential experience in the first experiment produced no effect on the behavioral scores. The second experiment included groups that received only 2 hr/day of enriched experience, and they benefited as much as groups that remained in the enriched environment 24 hr/day. The results of both experiments demonstrated significant beneficial effects of environment when bilateral lesions were made at a later age and when the periods of enriched experience were shorter than had previously been tested. Two additional experiments revealed significant effects of both lesions and environment on weight and RNA/DNA of brain regions.« less

The Flexible Faraday Cage

NASA Astrophysics Data System (ADS)

Gluck, Paul

2004-03-01

The Faraday ice-pail experiment is performed when studying the distribution of charges in conductors: Inside a hollow conductor the net charge is zero, and any excess charge resides on the outside surface.

Circulating adrenal hormones are not necessary for the development of sensitization to the psychomotor activating effects of amphetamine.

PubMed

Badiani, A; Morano, M I; Akil, H; Robinson, T E

1995-02-27

We reported previously that when amphetamine is given in NOVEL test cages both its acute psychomotor activating effects (rotational behaviour and locomotor activity) and the degree of sensitization are greater than when amphetamine is given in HOME cages that are physically identical to the NOVEL test cages. Since exposure to the NOVEL environment increases plasma corticosterone levels (Experiment 1) it is possible that the enhancement in the effects of amphetamine in the NOVEL condition is mediated by corticosterone. If this hypothesis is correct adrenalectomy (ADX) should abolish the difference between the HOME and NOVEL groups. This was tested in three independent experiments, in which the response (rotational behavior in Experiments 2 and 3; locomotor activity and rearing behavior in Experiment 4) to repeated injections of amphetamine was assessed in rats that underwent adrenalectomy (ADX) or a sham operation (SHAM). ADX animals received either no corticosterone replacement or one of two corticosterone replacement treatments. Adrenalectomy, with or without corticosterone replacement treatment, had no significant effect on the development of amphetamine sensitization, either in the HOME or the NOVEL environment. By contrast, the effects of adrenalectomy on the acute response to amphetamine varied depending on the behavioral measure and possibly on the dose of amphetamine (2.0 mg/kg, 3.0 mg/kg and 1.5 mg/kg IP, in Experiments 2, 3 and 4, respectively). We conclude that: (i) a stress-induced secretion of adrenal hormones is not responsible for the enhancement in sensitization to amphetamine seen in animals tested in a NOVEL environment; (ii) circulating adrenal hormones are not necessary for development of sensitization to the psychomotor activating effects of amphetamine.

Alteration in behavioral sensitivity to amphetamine after treatment with oxotremorine. Effect of dose and test environment.

PubMed

Gralewicz, Sławomir; Lutz, Piotr; Wiaderna, Dorota; Tomas, Tadeusz

2003-12-17

Our earlier experiment revealed that rats pretreated once with an anticholinesterase develop hyposensitivity to amphetamine (AMPH). One of the likely causes of this effect might be a transient hyperexcitation of the central muscarinic receptors. It has appeared, however, that rats pretreated with oxotremorine (OX), a muscarinic agonist, show an augmented behavioral response to AMPH weeks later. The present experiments were performed in order to obtain more information on the relationship between the OX-induced sensitization to AMPH and the OX dose and dosing regime (single or repeated), and to find out whether the environment associated with the acute effects of OX could affect the response to AMPH. In experiment 1, adult male rats were given a single i.p. injection of OX in home cages at a moderate (0.5 mg/kg) or high (1.0 mg/kg) dose. In experiment 2, the rats received eight 1.0 mg/kg doses of OX in the course of three days. After each injection, some animals returned to their home cages, and some were placed in the test cages for 30 min. In both experiments, the response to AMPH was assessed on day 21 after the treatment. The obtained results indicate that: (i) a single i.p. exposure to OX results in an increase of the rat's behavioral sensitivity to AMPH but the moderate dose is more effective in inducing this effect; (ii) repeated exposure to OX at high doses, in a regime enabling development of tolerance to the acute OX effects, does not alter the rat sensitivity to AMPH, and (iii) expression of the AMPH response is suppressed in environment which has been associated with acute effects of OX.

Danny Weber, a student experimenter, discusses experiment hardware for STS-7

NASA Technical Reports Server (NTRS)

1983-01-01

Danny Weber, a student from Cornell University, discusses the hardware for an experiment he devised, with Astronaut Norman E. Thagard, STS-7 mission specialist. The experiment is entitled 'Effect of weightlessness on arthritis'. The cage and monitoring equipment shown are designed to use rats as the subjects for the study. Weber was attending Hunter College High School when he submitted the experiment.

Assembly, Elasticity, and Structure of Lyotropic Chromonic Liquid Crystals and Disordered Colloids

NASA Astrophysics Data System (ADS)

Davidson, Zoey S.

This dissertation describes experiments which explore the structure and dynamics in two classes of soft materials: lyotropic chromonic liquid crystals and colloidal glasses and super-cooled liquids. The first experiments found that the achiral LCLCs, sunset yellow FCF (SSY) and disodium cromoglycate (DSCG) both exhibit spontaneous mirror symmetry breaking in the nematic phase driven by a giant elastic anisotropy of their twist modulus compared to their splay and bend moduli. Resulting structures of the confined LCLCs display interesting director configurations due to interplay of topologically required defects and twisted director fields. At higher concentrations, the LCLC compounds form columnar phases. We studied the columnar phase confined within spherical drops and discovered and understood configurations of the LC that sometimes led to non-spherical droplet shapes. The second experiments with SSY LCLCs confined in hollow cylinders uncovered director configurations which were driven in large measure by an exotic elastic modulus known as saddle-splay. We measured this saddle-splay modulus in a LCLC for the first time and found it to be more than 50 times greater than the twist elastic modulus. This large relative value of the saddle-splay modulus violates a theoretical result/assumption known as the Ericksen inequality. A third group of experiments on LCLCs explored the drying process of sessile drops containing SSY solutions, including evaporation dynamics, morphology, and deposition patterns. These drops differ from typical, well-studied evaporating colloidal drops primarily due to the LCLC's concentration-dependent isotropic, nematic, and columnar phases. Phase separation occurs during evaporation, creating surface tension gradients and significant density and viscosity variation within the droplet. Thus, the drying multiphase drops exhibit new convective currents, drop morphologies, deposition patterns, as well as a novel ordered crystalline phase. Finally, experiments in colloidal glasses and super-cooled liquids were initiated to probe the relationship between structure and dynamics in their constituent particles. The displacements of individual particles in the colloids can be decomposed into small cage fluctuations and large rearrangements into new cages. We found a correlation between the rate of rearrangement and the local cage structure associated with each particle. Particle trajectories of a two-dimensional binary mixture of soft colloids are captured by video microscopy. We use a machine learning method to calculate particle "softness'', which indicates the likelihood of rearrangement based on many radial structural features for each particle. We measured the residence time between consecutive rearrangements and related probability distribution functions (PDFs). The softness-dependent conditional PDF is well fit by an exponential with decay time decreasing monotonically with increasing softness. Using these data and a simple thermal activation model, we determined activation energies for rearrangements.

An inductively powered telemetry system for temperature, EKG, and activity monitoring

NASA Technical Reports Server (NTRS)

Fryer, T. B.; Lund, G. F.; Williams, B. A.

1978-01-01

An implant telemetry system for the simultaneous monitoring of temperature, activity, and EKG from small animals, such as rats, was designed with the feature that instead of a battery the system is energized by an inductive field. A 250 kHz resonant coil surrounds the cage (30 x 30 x 20 cm) and provides the approximately 100 microns of power required to operate the implant transmitter while allowing the animal unrestrained movement in the cage. The implant can also be battery operated if desired. RF transmission is in the 8-10 MHz band, which allows the use of a simple, essentially single IC chip, receiver.

An inductively powered telemetry system for temperature, EKG, and activity monitoring

NASA Technical Reports Server (NTRS)

Fryer, T. B.; Lund, G. F.; Williams, B. A.

1978-01-01

An implant telemetry system for the simultaneous monitoring of temperature, activity, and EKG from small animals, such as rats, has recently been designed with the novel feature that instead of a battery the system is energized by an inductive field. A 250 kHz resonant coil surrounds the cage (30 x 30 x 20 cm) and provides the approximately 100 microwatt of power required to operate the implant transmitter while allowing the animal unrestrained movement in the cage. The implant can also be battery operated if desired. RF transmission is in the 8-10 MHz band, which allows the use of a simple, essentially single IC chip, receiver.

A Sequential Insect Dispenser for Behavioral Experiments

ERIC Educational Resources Information Center

Gans, Carl; Mix, Harold

1974-01-01

Describes the construction and operation of an automatic insect dispenser suitable for feeding small vertebrates that are being maintained for behavioral experiments. The food morsels are squirted from their chambers an an air jet, and may be directed at a particluar portion of the cage or distributed to different areas. (JR)

Furnished cage system and hen well-being: Comparative effects of furnished cages and battery cages on behavioral exhibitions in White Leghorn chickens.

PubMed

Pohle, K; Cheng, H-W

2009-08-01

The battery cage system is being banned in the European Union before or by 2012, and the furnished cage system will be the only cage system allowed after 2012. This study was conducted to examine the different effects of caging systems, furnished cages vs. battery cages, on bird behaviors. One hundred ninety-two 1-d-old non-beak-trimmed Hy-Line W-36 White Leghorn chicks were reared using standard management practices in raised wire cages. At 19 wk of age, the birds were randomly assigned into battery cages or furnished cages. The battery cages were commercial wire cages containing 6 birds per cage, providing 645 cm(2) of floor space per birds. The furnished cages had wire floors and solid metal walls, with perches, a dustbathing area, scratch pads, and a nestbox area with a concealment curtain. Based on the company recommendations, 10 birds were housed per cage, providing a stocking density of 610 cm(2) of floor space per bird. Behavioral observations were conducted using the Noldus Observer software package. The birds were observed at 5-min intervals for the entire light period. The birds housed in battery cages had higher posture and behavioral transitions and increased time spent walking and performing exploratory behavior (P < 0.05, 0.01, respectively), which may indicate they were stressed, resulting in restlessness, whereas the birds housed in furnished cages had higher levels of preening (P < 0.05). Preening has been considered as a comfort behavior in birds. These results may suggest that furnished cages may be a favorable alternative system for housing birds by allowing them to perform certain natural behaviors.

Curating viscoelastic properties of icosahedral viruses, virus-based nanomaterials, and protein cages.

PubMed

Kant, Ravi; Rayaprolu, Vamseedhar; McDonald, Kaitlyn; Bothner, Brian

2018-06-01

The beauty, symmetry, and functionality of icosahedral virus capsids has attracted the attention of biologists, physicists, and mathematicians ever since they were first observed. Viruses and protein cages assemble into functional architectures in a range of sizes, shapes, and symmetries. To fulfill their biological roles, these structures must self-assemble, resist stress, and are often dynamic. The increasing use of icosahedral capsids and cages in materials science has driven the need to quantify them in terms of structural properties such as rigidity, stiffness, and viscoelasticity. In this study, we employed Quartz Crystal Microbalance with Dissipation technology (QCM-D) to characterize and compare the mechanical rigidity of different protein cages and viruses. We attempted to unveil the relationships between rigidity, radius, shell thickness, and triangulation number. We show that the rigidity and triangulation numbers are inversely related to each other and the comparison of rigidity and radius also follows the same trend. Our results suggest that subunit orientation, protein-protein interactions, and protein-nucleic acid interactions are important for the resistance to deformation of these complexes, however, the relationships are complex and need to be explored further. The QCM-D based viscoelastic measurements presented here help us elucidate these relationships and show the future prospect of this technique in the field of physical virology and nano-biotechnology.

Novel approach to the behavioural characterization of inbred mice: automated home cage observations.

PubMed

de Visser, L; van den Bos, R; Kuurman, W W; Kas, M J H; Spruijt, B M

2006-08-01

Here we present a newly developed tool for continuous recordings and analysis of novelty-induced and baseline behaviour of mice in a home cage-like environment. Aim of this study was to demonstrate the strength of this method by characterizing four inbred strains of mice, C57BL/6, DBA/2, C3H and 129S2/Sv, on locomotor activity. Strains differed in circadian rhythmicity, novelty-induced activity and the time-course of specific behavioural elements. For instance, C57BL/6 and DBA/2 mice showed a much faster decrease in activity over time than C3H and 129S2/Sv mice. Principal component analysis revealed two major factors within locomotor activity, which were defined as 'level of activity' and 'velocity/stops'. These factors were able to distinguish strains. Interestingly, mice that displayed high levels of activity in the initial phase of the home cage test were also highly active during an open-field test. Velocity and the number of stops during movement correlated positively with anxiety-related behaviour in the elevated plus maze. The use of an automated home cage observation system yields temporal changes in elements of locomotor activity with an advanced level of spatial resolution. Moreover, it avoids the confounding influence of human intervention and saves time-consuming human observations.

Construction of Polynuclear Lanthanide (Ln = Dy(III), Tb(III), and Nd(III)) Cage Complexes Using Pyridine-Pyrazole-Based Ligands: Versatile Molecular Topologies and SMM Behavior.

PubMed

Bala, Sukhen; Sen Bishwas, Mousumi; Pramanik, Bhaskar; Khanra, Sumit; Fromm, Katharina M; Poddar, Pankaj; Mondal, Raju

2015-09-08

Employment of two different pyridyl-pyrazolyl-based ligands afforded three octanuclear lanthanide(III) (Ln = Dy, Tb) cage compounds and one hexanuclear neodymium(III) coordination cage, exhibiting versatile molecular architectures including a butterfly core. Relatively less common semirigid pyridyl-pyrazolyl-based asymmetric ligand systems show an interesting trend of forming polynuclear lanthanide cage complexes with different coordination environments around the metal centers. It is noteworthy here that construction of lanthanide complex itself is a challenging task in a ligand system as soft N-donor rich as pyridyl-pyrazol. We report herein some lanthanide complexes using ligand containing only one or two O-donors compare to five N-coordinating sites. The resultant multinuclear lanthanide complexes show interesting magnetic and spectroscopic features originating from different spatial arrangements of the metal ions. Alternating current (ac) susceptibility measurements of the two dysprosium complexes display frequency- and temperature-dependent out-of-phase signals in zero and 0.5 T direct current field, a typical characteristic feature of single-molecule magnet (SMM) behavior, indicating different energy reversal barriers due to different molecular topologies. Another aspect of this work is the occurrence of the not-so-common SMM behavior of the terbium complex, further confirmed by ac susceptibility measurement.

Photodegradation of polyaromatic hydrocarbons in passive air samplers: Field testing different deployment chambers

USGS Publications Warehouse

Bartkow, M.E.; Kennedy, K.E.; Huckins, J.N.; Holling, N.; Komarova, T.; Muller, J.F.

2006-01-01

Semi-permeable membrane devices (SPMDs) were loaded with deuterated anthracene and pyrene as performance reference compounds (PRCs) and deployed at a test site in four different chambers (open and closed box chamber, bowl chamber and cage chamber) for 29 days. The losses of PRCs and the uptake of polyaromatic hydrocarbons (PAHs) from the ambient air were quantified. UV-B levels measured in each deployment chamber indicated that SPMDs would be exposed to the most UV-B in the cage chamber and open box chamber. Significantly less PAHs were quantified in SPMDs deployed in the cage chamber and open box chamber compared to samplers from the other two chambers, suggesting that photodegradation of PAHs had occurred. The loss of PRCs confirmed these results but also showed that photodegradation was occurring in the closed box chamber. The bowl chamber appears to provide the best protection from the influence of direct photodegradation. ?? 2006 Elsevier Ltd. All rights reserved.

Detecting Wear In Ball Bearings During Operation

NASA Technical Reports Server (NTRS)

Hine, Michael J.

1988-01-01

Strain-gauge signals at harmonics of ball-bearing-cage frequencies signify wear. Brief report describes experiments in continuing effort to interpret vibrations of machinery in terms of wear in ball bearing.

Laboratory tests for controlling poultry red mites (Dermanyssus gallinae) with predatory mites in small 'laying hen' cages.

PubMed

Lesna, Izabela; Sabelis, Maurice W; van Niekerk, Thea G C M; Komdeur, Jan

2012-12-01

To assess their potential to control poultry red mites (Dermanyssus gallinae), we tested selected predaceous mites (Androlaelaps casalis and Stratiolaelaps scimitus) that occur naturally in wild bird nests or sometimes spontaneously invade poultry houses. This was done under laboratory conditions in cages, each with 2-3 laying hens, initially 300 poultry red mites and later the release of 1,000 predators. These small-scale tests were designed to prevent mite escape from the cages and they were carried out in three replicates at each of three temperature regimes: 26, 30 (constant day and night) and 33-25 °C (day-night cycle). After 6 weeks total population sizes of poultry red mites and predatory mites were assessed. For the temperature regimes of 26 and 33/25 °C S. scimitus reduced the poultry red mite population relative to the control experiments by a factor 3 and 30, respectively, and A. casalis by a factor of 18 and 55, respectively. At 30 °C the predators had less effect on red mites, with a reduction of 1.3-fold for S. scimitus and 5.6-fold for A. casalis. This possibly reflected hen manure condition or an effect of other invertebrates in the hen feed. Poultry red mite control was not negatively affected by temperatures as high as 33 °C and was always better in trials with A. casalis than in those with S. scimitus. In none of the experiments predators managed to eradicate the population of poultry red mites. This may be due to a prey refuge effect since most predatory mites were found in and around the manure tray at the bottom of the cage, whereas most poultry red mites were found higher up in the cage (i.e. on the walls, the cover, the perch, the nest box and the food box). The efficacy of applying predatory mites in the poultry industry may be promoted by reducing this refuge effect, boosting predatory mite populations using alternative prey and prolonged predator release devices. Biocontrol success, however, will strongly depend on how the poultry is housed in practice (free range, cage or aviary systems) and on which chemicals are applied to disinfect poultry houses and to control other pests.

Temperature dependence of polyhedral cage volumes in clathrate hydrates

USGS Publications Warehouse

Chakoumakos, B.C.; Rawn, C.J.; Rondinone, A.J.; Stern, L.A.; Circone, S.; Kirby, S.H.; Ishii, Y.; Jones, C.Y.; Toby, B.H.

2003-01-01

The polyhedral cage volumes of structure I (sI) (carbon dioxide, methane, trimethylene oxide) and structure II (sII) (methane-ethane, propane, tetrahydrofuran, trimethylene oxide) hydrates are computed from atomic positions determined from neutron powder-diffraction data. The ideal structural formulas for sI and sII are, respectively, S2L6 ?? 46H2O and S16L???8 ?? 136H2O, where S denotes a polyhedral cage with 20 vertices, L a 24-cage, and L??? a 28-cage. The space-filling polyhedral cages are defined by the oxygen atoms of the hydrogen-bonded network of water molecules. Collectively, the mean cage volume ratio is 1.91 : 1.43 : 1 for the 28-cage : 24-cage : 20-cage, which correspond to equivalent sphere radii of 4.18, 3.79, and 3.37 A??, respectively. At 100 K, mean polyhedral volumes are 303.8, 227.8, and 158.8 A??3 for the 28-cage, 24-cage, and 20-cage, respectively. In general, the 20-cage volume for a sII is larger than that of a sI, although trimethylene oxide is an exception. The temperature dependence of the cage volumes reveals differences between apparently similar cages with similar occupants. In the case of trimethylene oxide hydrate, which forms both sI and sII, the 20-cages common to both structures contract quite differently. From 220 K, the sII 20-cage exhibits a smooth monotonic reduction in size, whereas the sI 20-cage initially expands upon cooling to 160 K, then contracts more rapidly to 10 K, and overall the sI 20-cage is larger than the sII 20-cage. The volumes of the large cages in both structures contract monotonically with decreasing temperature. These differences reflect reoriented motion of the trimethyelene oxide molecule in the 24-cage of sI, consistent with previous spectroscopic and calorimetric studies. For the 20-cages in methane hydrate (sI) and a mixed methane-ethane hydrate (sII), both containing methane as the guest molecule, the temperature dependence of the 20-cage volume in sII is much less than that in sI, but sII is overall larger in volume.

Small female rib cage fracture in frontal sled tests.

PubMed

Shaw, Greg; Lessley, David; Ash, Joseph; Poplin, Jerry; McMurry, Tim; Sochor, Mark; Crandall, Jeff

2017-01-02

The 2 objectives of this study are to (1) examine the rib and sternal fractures sustained by small stature elderly females in simulated frontal crashes and (2) determine how the findings are characterized by prior knowledge and field data. A test series was conducted to evaluate the response of 5 elderly (average age 76 years) female postmortem human subjects (PMHS), similar in mass and size to a 5th percentile female, in 30 km/h frontal sled tests. The subjects were restrained on a rigid planar seat by bilateral rigid knee bolsters, pelvic blocks, and a custom force-limited 3-point shoulder and lap belt. Posttest subject injury assessment included identifying rib cage fractures by means of a radiologist read of a posttest computed tomography (CT) and an autopsy. The data from a motion capture camera system were processed to provide chest deflection, defined as the movement of the sternum relative to the spine at the level of T8.  A complementary field data investigation involved querying the NASS-CDS database over the years 1997-2012. The targeted cases involved belted front seat small female passenger vehicle occupants over 40 years old who were injured in 25 to 35 km/h delta-V frontal crashes (11 to 1 o'clock). Peak upper shoulder belt tension averaged 1,970 N (SD = 140 N) in the sled tests. For all subjects, the peak x-axis deflection was recorded at the sternum with an average of -44.5 mm or 25% of chest depth. The thoracic injury severity based on the number and distribution of rib fractures yielded 4 subjects coded as Abbreviated Injury Scale (AIS) 3 (serious) and one as AIS 5 (critical). The NASS-CDS field data investigation of small females identified 205 occupants who met the search criteria. Rib fractures were reported for 2.7% of the female occupants. The small elderly test subjects sustained a higher number of rib cage fractures than expected in what was intended to be a minimally injurious frontal crash test condition. Neither field studies nor prior laboratory frontal sled tests conducted with 50th percentile male PMHS predicted the injury severity observed. Although this was a limited study, the results justify further exploration of the risk of rib cage injury for small elderly female occupants.

Housing and dustbathing effects on northern fowl mites (Ornithonyssus sylviarum) and chicken body lice (Menacanthus stramineus) on hens.

PubMed

Martin, C D; Mullens, B A

2012-09-01

Hen housing (cage or cage-free) did not impact overall abundances of northern fowl mites, Ornithonyssus sylviarum (Canestrini & Fanzago) (Acari: Macronyssidae), or chicken body lice, Menacanthus stramineus (Nitzsch) (Phthiraptera: Menoponidae). Cage-free hens received a dustbox with sand plus diatomaceous earth (DE), kaolin clay or sulphur. Weekly use varied from none to 100% of hens; 73% of hens used the dustbox at least once. Ectoparasite populations on dustbathing hens (users) were compared with those on non-user cage-free and caged hens. All materials reduced ectoparasites on user hens by 80-100% after 1 week of dustbox use. Diatomaceous earth and kaolin failed to reduce ectoparasites on non-user hens, and ectoparasites on user hens recovered after dustbox removal. A sulphur dustbox eliminated mites from all hens (including non-users) within 2-4 weeks. Residual sulphur controlled mites until the end of the experiment (up to 9 weeks), even after the dustbox was removed. Louse populations on hens using the sulphur dustbox were reduced in 1-2 weeks. Residual sulphur effects were less evident in lice, but the use of a sulphur dustbox by a higher proportion of hens extended louse control to all hens. This is the first experimental study to show that bird dustbathing in naturally and widely available dust materials (particularly kaolin) can suppress ectoparasites and thus the behaviour is probably adaptive. © 2012 The Authors. Medical and Veterinary Entomology © 2012 The Royal Entomological Society.

US Army Research Laboratory (ARL) Standard for Characterization of Electric-Field Sensors, 10 Hz to 10 kHz

DTIC Science & Technology

2016-11-01

Disclaimers The findings in this report are not to be construed as an official Department of the Army position unless so designated by other...unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT The US Army Research Laboratory (ARL) has designed and build a one-of-a-kind electric-field sensor...direction. (Right) Computer- aided design model of the ARL electric-field cage with insulated mounting

Field-Based Approach for Assessing the Impact of Treated Pulp and Paper Mill Effluent on Endogenous Metabolites of Fathead Minnows (Pimephales promelas)

EPA Science Inventory

A field-based metabolomic study was conducted during a shutdown of a pulp and paper mill (PPM) to assess the impacts of treated PPM effluent on endogenous polar metabolites in fathead minnow (FHM; Pimephales promelas) livers. Caged male and female FHMs were deployed at a Great La...

Effect of a change in housing conditions on body weight, behavior and brain neurotransmitters in male C57BL/6J mice.

PubMed

Pasquarelli, Noemi; Voehringer, Patrizia; Henke, Julia; Ferger, Boris

2017-08-30

The development of modern housing regimes such as individually ventilated cage (IVC) systems has become very popular and attractive in order to reduce spreading of pathogenic organisms and to lower the risk to develop a laboratory animal allergy for staff members. Additionally, optimal housing of laboratory animals contributes to improve animal health status and ensures high and comparable experimental and animal welfare standards. However, it has not been clearly elucidated whether 1) a change to IVC systems have an impact on various physiological phenotypic parameters of mice when compared to conventional, standard cages and 2) if this is further affected by changing from social to single housing. Therefore, we investigated the influence of a change in housing conditions (standard cages with social housing changed to standard or IVC cages combined with social or single housing) on body weight, behavior and a neurochemical fingerprint of male C57BL/6J mice. Body weight progression was significantly reduced when changing mice to single or social IVC cages as well as in single standard cages when compared to social standard housing. Automated motor activity measurement in the open field showed that mice maintained in social husbandry with standard cages displayed the lowest exploratory behavior but the highest activity difference upon amphetamine treatment. Elevated plus maze test revealed that a change to IVC single and social housing as well as single standard housing produced anxiety-related behavior when compared to maintenance in social standard housing. Additionally, postmortem neurochemical analysis of the striatum using high-performance liquid chromatography coupled to electrochemical detection showed significant differences in striatal dopamine and serotonin turnover levels. In summary, our data indicate a crucial influence of a change in housing conditions on several mouse phenotype parameters. We propose that the maintenance of well-defined housing conditions is mandatory to ensure reproducible and comparable results and contributes to the application of the 3R refinement principle in animal studies by contributing to welfare and hygienical standards. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of separation of resources on behaviour, physical condition and production of laying hens in furnished cages.

PubMed

Shimmura, T; Azuma, T; Eguchi, Y; Uetake, K; Tanaka, T

2009-01-01

1. Based on our previous studies, we designed a medium-sized furnished cage with a dust bath and nest box on both sides of the cage (MFS) and evaluated its usefulness. 2. We used 180 White Leghorn layers. At the age of 17 weeks, the birds were distributed at random into one of the 4 cage designs: conventional cages (CC; 6 cages and 5 hens per cage), small (SF; 6 cages and 5 hens per cage) and medium furnished cages (MFL; 6 cages and 10 hens per cage) with a 'localised' dust bath and nest box on one side of the cage, and MFS (6 cages and 10 hens per cage). The total allocation of resources per bird was similar for all furnished cage designs. Behaviour, physical condition and production were measured in each cage. 3. Moving was more frequent in MFS and MFL than in CC and SF. The proportion of hens performing aggressive pecking and severe feather pecking was higher in MFL than CC and SF. These aggressive interactions occurred frequently in the dust bath area in MFL; however, these tendencies were not found in MFS. Egg production and egg mass were lower in MFL than in SF, while the production in MFS was similar to those in CC and SF. MFS hens laid eggs on the cage floor more often than in MFL. 4. In conclusion, these results demonstrate the possible usefulness of MFS. However, some inconsistent results and ways of improving MFS design were also identified.

Polymers containing borane or carborane cage compounds and related applications

DOEpatents

Bowen, III, Daniel E; Eastwood, Eric A

2013-04-23

Polymers comprising residues of cage compound monomers having at least one polyalkoxy silyl substituent are provided. The cage compound monomers are selected from borane cage compound monomers comprising at least 7 cage atoms and/or carborane cage compound monomers comprising 7 to 11 cage compound monomers. Such polymers can further comprise one or more reactive matrices and/or co-monomers covalently bound with the cage compound monomer residues. Articles of manufacture comprising such polymers are also disclosed.

Effects of lambda-cyhalothrin on mosquito larvae and predatory aquatic insects.

PubMed

Lawler, Sharon P; Dritz, Deborah A; Christiansen, Julie A; Cornel, Anthony J

2007-03-01

Agricultural insecticides can affect mosquito production in rice fields by controlling mosquitoes, disrupting biological control or contributing to selection of insecticide resistance. The duration of insecticidal activity of the pyrethroid lambda-cyhalothrin was quantified on predatory insects in rice fields and on three kinds of mosquito larva: a pyrethroid-susceptible strain of Culex tarsalis Coquillet, a pyrethroid-resistant strain of Cx pipiens L. (sensu lato) and non-resistant Cx pipiens s.l. Lambda-cyhalothrin killed most caged, susceptible mosquitoes for up to 21 days. It killed fewer resistant Cx pipiens s.l., but suppressed their survival for over a week. Lambda-cyhalothrin suppressed field populations of predatory insects through day 29. Agricultural use of lambda-cyhalothrin can provide incidental mosquito control. However, the pyrethroid persisted in sediment and gradually decreased in activity, which could contribute to selection of pyrethroid-resistant mosquitoes. Because caged mosquitoes showed good survival before predators recovered, disruption of biological control is possible. It is therefore advisable for growers and mosquito control agencies to communicate about pesticide use. Copyright 2006 Society of Chemical Industry.

[Metabolism of rat liver in the electrostatic field and in the faraday cage before and after hepatectomy (author's transl)].

PubMed

Klingenberg, H G; Möse, J R; Fischer, G; Porta, J; Sadjak, A

1975-10-01

Investigations were performed with the aim of establishing the influence of various environmental conditions (such as steady field conditions, climatized laboratories, Faraday's cage) on a number of enzymic activities in the rat (including glutamic oxaloacetic tic transaminase, glutamic pyruvic transaminase, lactic dehydrogenase, gamma-glutamyl transpeptidase, acid phosphatase), as well as the serum concentrations of triglycerides, the oxygen consumption of hepatic parenchyma cells, and the influence on the incorporation of 3H-thymidine (following partial hepatectomy). In the steady field, the activities of the cytoplasmic enzymes (GOT, GPT, LDH) were higher then under Faraday conditions. The same applies both to the hepatic oxygen consumption and to the neutral fat serum levels. The control values always remained within the range of the results obtained under steady field or Faraday conditions. In the structure-linked enzymes (gamma-glutamyl transpeptidase, acid phosphatase) the results were not uniform. Following partial hepatectomy, and under steady field conditions, the serum triglyceride concentrations showed a less pronounced drop than they did in the controls. Under selected environmental conditions, the results obtained lie within the physiological range. The present findings, therefore, do not permit definite conclusions to be drawn on favourable or unfavourable effects exerted by the different types of electroclimates.

Analysing the oviposition behaviour of malaria mosquitoes: design considerations for improving two-choice egg count experiments.

PubMed

Okal, Michael N; Lindh, Jenny M; Torr, Steve J; Masinde, Elizabeth; Orindi, Benedict; Lindsay, Steve W; Fillinger, Ulrike

2015-06-20

Choice egg-count bioassays are a popular tool for analysing oviposition substrate preferences of gravid mosquitoes. This study aimed at improving the design of two-choice experiments for measuring oviposition substrates preferences of the malaria vector Anopheles gambiae senso lato, a mosquito that lays single eggs. In order to achieve high egg-laying success of female An. gambiae sensu stricto (s.s.) and Anopheles arabiensis mosquitoes in experiments, four factors were evaluated: (1) the time provided for mating; (2) the impact of cage size, mosquito age and female body size on insemination; (3) the peak oviposition time; and, (4) the host sources of blood meal. Choice bioassays, with one mosquito released in each cage containing two oviposition cups both with the same oviposition substrate (100 ml water), were used to measure and adjust for egg-laying characteristics of the species. Based on these characteristics an improved design for the egg-count bioassay is proposed. High oviposition rates [84%, 95% confidence interval (CI) 77-89%] were achieved when 300 male and 300 blood-fed female An. gambiae s.s. were held together in a cage for 4 days. The chances for oviposition dropped (odds ratio 0.30; 95% CI 0.14-0.66) when human host source of blood meal was substituted with a rabbit but egg numbers per female were not affected. The number of eggs laid by individual mosquitoes was overdispersed (median = 52, eggs, interquartile range 1-214) and the numbers of eggs laid differed widely between replicates, leading to a highly heterogeneous variance between groups and/or rounds of experiments. Moreover, one-third of mosquitoes laid eggs unequally in both cups with similar substrates giving the illusion of choice. Sample size estimations illustrate that it takes 165 individual mosquitoes to power bioassays sufficiently (power = 0.8, p = 0.05) to detect a 15% shift in comparative preferences of two treatments. Two-choice egg count bioassays with Anopheles are best done with a two-tier design that (1) implements a parallel series of experiments with mosquitoes given a choice of two identical substrates choices and, (2) uses a single mosquito in each test cage rather than groups of mosquitoes to assess the preference of a test or control solution. This approach, with sufficient replication, lowers the risk detecting pseudopreferences.

Effect of housing arrangement on fecal-oral transmission of avian hepatitis E virus in chicken flocks.

PubMed

Liu, Baoyuan; Sun, Yani; Chen, Yiyang; Du, Taofeng; Nan, Yuchen; Wang, Xinjie; Li, Huixia; Huang, Baicheng; Zhang, Gaiping; Zhou, En-Min; Zhao, Qin

2017-09-07

Avian hepatitis E virus (HEV) infection is common in chicken flocks in China, as currently no measures exist to prevent the spread of the disease. In this study, we analyzed the effect of caged versus cage-free housing arrangements on avian HEV transmission. First, 127 serum and 110 clinical fecal samples were collected from 4 chicken flocks including the two arrangements in Shaanxi Province, China and tested for HEV antibodies and/or virus. Concurrently, 36 specific-pathogen-free chickens were divided equally into four experimental living arrangement groups, designated cage-free (Inoculated), caged (Inoculated), cage-free (Negative) and caged (Negative) groups. In caged groups, three cages contained 3 chickens each. Three chickens each from cage-free (Inoculated) and caged (Inoculated) groups (one chicken of each cage) were inoculated by cutaneous ulnar vein with the same dose of avian HEV, respectively. The cage-free (Negative) and caged (Negative) groups served as negative control. Serum and fecal samples were collected at 1 to 7 weeks post-inoculation (wpi) and liver lesions were scored at 7 wpi. The results of serology showed that the avian HEV infection rate (54.10%) of the cage-free chickens was significantly higher than the one (12.12%) for caged chickens (P < 0.05). Also, the rate of detection of avian HEV RNA in the clinical fecal samples was significantly higher in the cage-free (22.80%, 13/57) than caged birds (5.66%, 3/53). Moreover, under experimental conditions, the infected number of uninoculated cage-free chickens (6) was significantly higher than the one for the uninoculated caged birds (2), as evidenced by seroconversion, fecal virus shedding, viremia and gross and microscopic liver lesions. These results suggest that reduction of contact with feces as seen in the caged arrangement of housing chickens can reduce avian HEV transmission. This study provides insights for prevention and control of avian HEV infection in chicken flocks.

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

PubMed

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

2009-02-01

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

Classification Studies in an Advanced Air Classifier

NASA Astrophysics Data System (ADS)

Routray, Sunita; Bhima Rao, R.

2016-10-01

In the present paper, experiments are carried out using VSK separator which is an advanced air classifier to recover heavy minerals from beach sand. In classification experiments the cage wheel speed and the feed rate are set and the material is fed to the air cyclone and split into fine and coarse particles which are collected in separate bags. The size distribution of each fraction was measured by sieve analysis. A model is developed to predict the performance of the air classifier. The objective of the present model is to predict the grade efficiency curve for a given set of operating parameters such as cage wheel speed and feed rate. The overall experimental data with all variables studied in this investigation is fitted to several models. It is found that the present model is fitting good to the logistic model.

Numerical modelling of organic waste dispersion from fjord located fish farms

NASA Astrophysics Data System (ADS)

Ali, Alfatih; Thiem, Øyvind; Berntsen, Jarle

2011-07-01

In this study, a three-dimensional particle tracking model coupled to a terrain following ocean model is used to investigate the dispersion and the deposition of fish farm particulate matter (uneaten food and fish faeces) on the seabed due to tidal currents. The particle tracking model uses the computed local flow field for advection of the particles and random movement to simulate the turbulent diffusion. Each particle is given a settling velocity which may be drawn from a probability distribution according to settling velocity measurements of faecal and feed pellets. The results show that the maximum concentration of organic waste for fast sinking particles is found under the fish cage and continue monotonically decreasing away from the cage area. The maximum can split into two maximum peaks located at both sides of the centre of the fish cage area in the current direction. This process depends on the sinking time (time needed for a particle to settle at the bottom), the tidal velocity and the fish cage size. If the sinking time is close to a multiple of the tidal period, the maximum concentration point will be under the fish cage irrespective of the tide strength. This is due to the nature of the tidal current first propagating the particles away and then bringing them back when the tide reverses. Increasing the cage size increases the likelihood for a maximum waste accumulation beneath the fish farm, and larger farms usually means larger biomasses which can make the local pollution even more severe. The model is validated by using an analytical model which uses an exact harmonic representation of the tidal current, and the results show an excellent agreement. This study shows that the coupled ocean and particle model can be used in more realistic applications to help estimating the local environmental impact due to fish farms.

Protein cage assembly across multiple length scales.

PubMed

Aumiller, William M; Uchida, Masaki; Douglas, Trevor

2018-05-21

Within the materials science community, proteins with cage-like architectures are being developed as versatile nanoscale platforms for use in protein nanotechnology. Much effort has been focused on the functionalization of protein cages with biological and non-biological moieties to bring about new properties of not only individual protein cages, but collective bulk-scale assemblies of protein cages. In this review, we report on the current understanding of protein cage assembly, both of the cages themselves from individual subunits, and the assembly of the individual protein cages into higher order structures. We start by discussing the key properties of natural protein cages (for example: size, shape and structure) followed by a review of some of the mechanisms of protein cage assembly and the factors that influence it. We then explore the current approaches for functionalizing protein cages, on the interior or exterior surfaces of the capsids. Lastly, we explore the emerging area of higher order assemblies created from individual protein cages and their potential for new and exciting collective properties.

Bubble-Free Containers For Liquids In Microgravity

NASA Technical Reports Server (NTRS)

Kornfeld, Dale M.; Antar, Basil L.

1995-01-01

Reports discuss entrainment of gas bubbles during handling of liquids in microgravity, and one report proposes containers filled with liquids in microgravity without entraining bubbles. Bubbles are troublesome in low-gravity experiments - particularly in biological experiments. Wire-mesh cage retains liquid contents without solid wall, because in microgravity, surface tension of liquid exerts sufficient confining force.

A Kinetic Model of Trp-Cage Folding from Multiple Biased Molecular Dynamics Simulations

PubMed Central

Marinelli, Fabrizio; Pietrucci, Fabio; Laio, Alessandro; Piana, Stefano

2009-01-01

Trp-cage is a designed 20-residue polypeptide that, in spite of its size, shares several features with larger globular proteins. Although the system has been intensively investigated experimentally and theoretically, its folding mechanism is not yet fully understood. Indeed, some experiments suggest a two-state behavior, while others point to the presence of intermediates. In this work we show that the results of a bias-exchange metadynamics simulation can be used for constructing a detailed thermodynamic and kinetic model of the system. The model, although constructed from a biased simulation, has a quality similar to those extracted from the analysis of long unbiased molecular dynamics trajectories. This is demonstrated by a careful benchmark of the approach on a smaller system, the solvated Ace-Ala3-Nme peptide. For the Trp-cage folding, the model predicts that the relaxation time of 3100 ns observed experimentally is due to the presence of a compact molten globule-like conformation. This state has an occupancy of only 3% at 300 K, but acts as a kinetic trap. Instead, non-compact structures relax to the folded state on the sub-microsecond timescale. The model also predicts the presence of a state at of 4.4 Å from the NMR structure in which the Trp strongly interacts with Pro12. This state can explain the abnormal temperature dependence of the and chemical shifts. The structures of the two most stable misfolded intermediates are in agreement with NMR experiments on the unfolded protein. Our work shows that, using biased molecular dynamics trajectories, it is possible to construct a model describing in detail the Trp-cage folding kinetics and thermodynamics in agreement with experimental data. PMID:19662155

A kinetic model of trp-cage folding from multiple biased molecular dynamics simulations.

PubMed

Marinelli, Fabrizio; Pietrucci, Fabio; Laio, Alessandro; Piana, Stefano

2009-08-01

Trp-cage is a designed 20-residue polypeptide that, in spite of its size, shares several features with larger globular proteins.Although the system has been intensively investigated experimentally and theoretically, its folding mechanism is not yet fully understood. Indeed, some experiments suggest a two-state behavior, while others point to the presence of intermediates. In this work we show that the results of a bias-exchange metadynamics simulation can be used for constructing a detailed thermodynamic and kinetic model of the system. The model, although constructed from a biased simulation, has a quality similar to those extracted from the analysis of long unbiased molecular dynamics trajectories. This is demonstrated by a careful benchmark of the approach on a smaller system, the solvated Ace-Ala3-Nme peptide. For theTrp-cage folding, the model predicts that the relaxation time of 3100 ns observed experimentally is due to the presence of a compact molten globule-like conformation. This state has an occupancy of only 3% at 300 K, but acts as a kinetic trap.Instead, non-compact structures relax to the folded state on the sub-microsecond timescale. The model also predicts the presence of a state at Calpha-RMSD of 4.4 A from the NMR structure in which the Trp strongly interacts with Pro12. This state can explain the abnormal temperature dependence of the Pro12-delta3 and Gly11-alpha3 chemical shifts. The structures of the two most stable misfolded intermediates are in agreement with NMR experiments on the unfolded protein. Our work shows that, using biased molecular dynamics trajectories, it is possible to construct a model describing in detail the Trp-cage folding kinetics and thermodynamics in agreement with experimental data.

Compound-specific sulfur isotope analysis of thiadiamondoids of oils from the Smackover Formation, USA

USGS Publications Warehouse

Zvi Gvirtzman,; Ward Said-Ahmad,; Ellis, Geoffrey S.; Ronald J. Hill,; J. Michael Moldowan,; Zhibin Wei,; Alon Amrani,

2015-01-01

Thiadiamondoids (TDs) are diamond-like compounds with a sulfide bond located within the cage structure. These compounds were suggested as a molecular proxy for the occurrence and extent of thermochemical sulfate reduction (TSR). Compound-specific sulfur-isotope analysis of TDs may create a multi-parameter system, based on molecular and δ34S values that may be sensitive over a wider range of TSR and thermal maturation stages. In this study, we analyzed a suite of 12 Upper Jurassic oil and condensate samples generated from source rocks in the Smackover Formation to perform a systematic study of the sulfur isotope distribution in thiadiamondoids (one and two cages). For comparison we measured the δ34S composition of benzothiophenes (BTs) and dibenzothiophenes (DBTs). We also conducted pyrolysis experiments with petroleum and model compounds to have an insight into the formation mechanisms of TDs. The δ34S of the TDs varied significantly (ca 30‰) between the different oils depending on the degree of TSR alteration. The results showed that within the same oil, the one-cage TDs were relatively uniform, with 34S enriched values similar to those of the coexisting BTs. The two-cage TDs had more variable δ34S values that range from the δ34S values of BTs to those of the DBTs, but with general 34S depletion relative to one cage TDs. Hydrous pyrolysis experiments (360 °C, 40 h) with either CaSO4 or elemental S (equivalent S molar concentrations) and adamantane as a model compound demonstrate the formation of one cage TDs in relatively low yields (<0.2%). Higher concentrations of TDs were observed in the elemental sulfur experiments, most likely because of the higher rates of reaction with adamantane under these experimental conditions. These results show that the formation of TDs is not exclusive to TSR reactions, and that they can also form by reaction with reduced S species apart from sulfate reduction, though at low yields. Oxygenated compounds, most notably 2-thiaadamantanone and phenol, were also formed during these pyrolysis experiments. This may represent the first stage in the formation of sulfurized compounds and the oxidation of organic matter under TSR conditions. Pyrolysis experiments with elemental S and a TD-enriched oil showed that the δ34S values of the TDs did not change, whereas the BTs did change significantly. It is therefore concluded that TDs do not exchange S atoms with coexisting inorganic reduced sulfur species. They can only change their δ34S values via addition of newly generated TDs that form predominantly during TSR. We therefore suggest that TDs will preserve their δ34S values even under high-temperature reservoir conditions and will reflect the original sulfates δ34S value. The combination of TDs, BTs, and DBTs δ34S values and concentrations allowed for a more reliable detection of the occurrence and extent of TSR than either proxy alone. It showed that except for two oils, all of the oils that were measured in this study were affected by TSR or TSR-sourced H2S, to some degree. It is still not known if some of the oils with the lower concentrations of TDs and enriched δ34S values (close to sulfate minerals) were affected by TSR or by a secondary charge of 34S-enriched H2S.

Laboratory studies of aerosol electrification and experimental evidence for electrical breakdown at different scales.

NASA Astrophysics Data System (ADS)

Alois, Stefano; Merrison, Jonathan; Iversen, Jens Jacob; Sesterhenn, Joern

2017-04-01

Contact electrification between different particles size/material can lead to electric field generation high enough to produce electrical breakdown. Experimental studies of solid aerosol contact electrification (Alois et al., 2016) has shown various electrical breakdown phenomena; these range from field emission at the contact site (nm-scale) limiting particle surface charge concentration, to visible electrical discharges (cm-scale) observed both with the use of an electrometer and high-speed camera. In these experiments micron-size particles are injected into a low-pressure chamber, where they are deviated by an applied electric field. A laser Doppler velocimeter allows the simultaneous determination of particle size and charge of single grains. Results have shown an almost constant surface charge concentration, which is likely to be due to charge limitation by field emission at the contact site between particle and injector. In a second measurement technique, the electrically isolated injector tube (i.e. a Faraday cage) is connected to an oscilloscope and synchronised to a high speed camera filming the injection. Here the electrification of a large cloud of particles can be quantified and discharging effects studied. This study advances our understanding on the physical processes leading to electrification and electrical breakdown mechanisms.

Differential behavioural and endocrine responses of common voles (Microtus arvalis) to nest predators and resource competitors.

PubMed

Liesenjohann, Monique; Liesenjohann, Thilo; Palme, Rupert; Eccard, Jana Anja

2013-09-08

Adaptive behavioural strategies promoting co-occurrence of competing species are known to result from a sympatric evolutionary past. Strategies should be different for indirect resource competition (exploitation, e.g., foraging and avoidance behaviour) than for direct interspecific interference (e.g., aggression, vigilance, and nest guarding). We studied the effects of resource competition and nest predation in sympatric small mammal species using semi-fossorial voles and shrews, which prey on vole offspring during their sensitive nestling phase. Experiments were conducted in caged outdoor enclosures. Focus common vole mothers (Microtus arvalis) were either caged with a greater white-toothed shrew (Crocidura russula) as a potential nest predator, with an herbivorous field vole (Microtus agrestis) as a heterospecific resource competitor, or with a conspecific resource competitor. We studied behavioural adaptations of vole mothers during pregnancy, parturition, and early lactation, specifically modifications of the burrow architecture and activity at burrow entrances. Further, we measured pre- and postpartum faecal corticosterone metabolites (FCMs) of mothers to test for elevated stress hormone levels. Only in the presence of the nest predator were prepartum FCMs elevated, but we found no loss of vole nestlings and no differences in nestling body weight in the presence of the nest predator or the heterospecific resource competitor. Although the presence of both the shrew and the field vole induced prepartum modifications to the burrow architecture, only nest predators caused an increase in vigilance time at burrow entrances during the sensitive nestling phase. Voles displayed an adequate behavioural response for both resource competitors and nest predators. They modified burrow architecture to improve nest guarding and increased their vigilance at burrow entrances to enhance offspring survival chances. Our study revealed differential behavioural adaptations to resource competitors and nest predators.

Differential behavioural and endocrine responses of common voles (Microtus arvalis) to nest predators and resource competitors

PubMed Central

2013-01-01

Background Adaptive behavioural strategies promoting co-occurrence of competing species are known to result from a sympatric evolutionary past. Strategies should be different for indirect resource competition (exploitation, e.g., foraging and avoidance behaviour) than for direct interspecific interference (e.g., aggression, vigilance, and nest guarding). We studied the effects of resource competition and nest predation in sympatric small mammal species using semi-fossorial voles and shrews, which prey on vole offspring during their sensitive nestling phase. Experiments were conducted in caged outdoor enclosures. Focus common vole mothers (Microtus arvalis) were either caged with a greater white-toothed shrew (Crocidura russula) as a potential nest predator, with an herbivorous field vole (Microtus agrestis) as a heterospecific resource competitor, or with a conspecific resource competitor. Results We studied behavioural adaptations of vole mothers during pregnancy, parturition, and early lactation, specifically modifications of the burrow architecture and activity at burrow entrances. Further, we measured pre- and postpartum faecal corticosterone metabolites (FCMs) of mothers to test for elevated stress hormone levels. Only in the presence of the nest predator were prepartum FCMs elevated, but we found no loss of vole nestlings and no differences in nestling body weight in the presence of the nest predator or the heterospecific resource competitor. Although the presence of both the shrew and the field vole induced prepartum modifications to the burrow architecture, only nest predators caused an increase in vigilance time at burrow entrances during the sensitive nestling phase. Conclusion Voles displayed an adequate behavioural response for both resource competitors and nest predators. They modified burrow architecture to improve nest guarding and increased their vigilance at burrow entrances to enhance offspring survival chances. Our study revealed differential behavioural adaptations to resource competitors and nest predators. PMID:24010574

Computational comparison of three posterior lumbar interbody fusion techniques by using porous titanium interbody cages with 50% porosity.

PubMed

Lee, Yung-Heng; Chung, Chi-Jen; Wang, Chih-Wei; Peng, Yao-Te; Chang, Chih-Han; Chen, Chih-Hsien; Chen, Yen-Nien; Li, Chun-Ting

2016-04-01

This study investigated the biomechanical response of porous cages and lumbar spine segments immediately after surgery and after bone fusion, in addition to the long-term effects of various posterior lumbar interbody fusion (PLIF) techniques, by using the finite element method. Lumbar L3-L4 models based on three PLIF techniques (a single cage at the center of the intervertebral space, a single cage half-anterior to the intervertebral space, and two cages bilateral to the intervertebral space) with and without bone ingrowth were used to determine the biomechanical response of porous cages and lumbar segments instrumented with porous titanium cages (cage porosity=50%, pore diameter=1mm). The results indicated that bone fusion enhanced the stability of the lumbar segments with porous cages without any posterior instrumentation and reduced the peak von Mises stress in the cortical bones and porous cages. Two cages placed bilateral to the intervertebral space achieved the highest structural stability in the lumbar segment and lowest von Mises stress in the cages under both bone fusion conditions. Under identical loading (2-Nm), the range of motion in the single cage at the center of the intervertebral space with bone fusion decreased by 11% (from 1.18° to 1.05°) during flexion and by 66.5% (from 4.46° to 1.5°) during extension in the single cage half-anterior to the intervertebral space with bone fusion compared with no-fusion models. Thus, two porous titanium cages with 50% porosity can achieve high stability of a lumbar segment with PLIF. If only one cage is available, placing the cage half-anterior to the intervertebral space is recommended for managing degenerated lumbar segments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Do position and size matter? An analysis of cage and placement variables for optimum lordosis in PLIF reconstruction.

PubMed

Landham, Priyan R; Don, Angus S; Robertson, Peter A

2017-11-01

To examine monosegmental lordosis after posterior lumbar interbody fusion (PLIF) surgery and relate lordosis to cage size, shape, and placement. Eighty-three consecutive patients underwent single-level PLIF with paired identical lordotic cages involving a wide decompression and bilateral facetectomies. Cage parameters relating to size (height, lordosis, and length) and placement (expressed as a ratio relative to the length of the inferior vertebral endplate) were recorded. Centre point ratio (CPR) was the distance to the centre of both cages and indicated mean position of both cages. Posterior gap ratio (PGR) was the distance to the most posterior cage and indicated position and cage length indirectly. Relationships between lordosis and cage parameters were explored. Mean lordosis increased by 5.98° (SD 6.86°). The cages used varied in length from 20 to 27 mm, in lordosis from 10° to 18°, and in anterior cage height from 10 to 17 mm. The mean cage placement as determined by CPR was 0.54 and by PGR was 0.16. The significant correlations were: both CPR and PGR with lordosis gain at surgery (r = 0.597 and 0.537, respectively, p < 0.001 both), cage lordosis with the final lordosis (r = 0.234, p < 0.05), and anterior cage height was negatively correlated with a change in lordosis (r = -0.297, p < 0.01). Cage size, shape, and position, in addition to surgical technique, determine lordosis during PLIF surgery. Anterior placement with sufficient "clear space" behind the cages is recommended. In addition, cages should be of moderate height and length, so that they act as an effective pivot for lordosis.

Secondary Electron Emission from Dust and Its Effect on Charging

NASA Astrophysics Data System (ADS)

Saikia, B. K.; Kakati, B.; Kausik, S. S.; Bandyopadhyay, M.

2011-11-01

Hydrogen plasma is produced in a plasma chamber by striking discharge between incandescent tungsten filaments and the permanent magnetic cage [1], which is grounded. The magnetic cage has a full line cusped magnetic field geometry used to confine the plasma elements. A cylindrical Langmuir probe is used to study the plasma parameters in various discharge conditions. The charge accumulated on the dust particles is calculated using the capacitance model and the dust current is measured by the combination of a Faraday cup and an electrometer at different discharge conditions. It is found Secondary electron emission from dust having low emission yield effects the charging of dust particles in presence of high energetic electrons.

Feasibility of a Short-Arm Centrifuge for Mouse Hypergravity Experiments.

PubMed

Morita, Hironobu; Obata, Koji; Abe, Chikara; Shiba, Dai; Shirakawa, Masaki; Kudo, Takashi; Takahashi, Satoru

2015-01-01

To elucidate the pure impact of microgravity on small mammals despite uncontrolled factors that exist in the International Space Station, it is necessary to construct a 1 g environment in space. The Japan Aerospace Exploration Agency has developed a novel mouse habitat cage unit that can be installed in the Cell Biology Experiment Facility in the Kibo module of the International Space Station. The Cell Biology Experiment Facility has a short-arm centrifuge to produce artificial 1 g gravity in space for mouse experiments. However, the gravitational gradient formed inside the rearing cage is larger when the radius of gyration is shorter; this may have some impact on mice. Accordingly, biological responses to hypergravity induced by a short-arm centrifuge were examined and compared with those induced by a long-arm centrifuge. Hypergravity induced a significant Fos expression in the central nervous system, a suppression of body mass growth, an acute and transient reduction in food intake, and impaired vestibulomotor coordination. There was no difference in these responses between mice raised in a short-arm centrifuge and those in a long-arm centrifuge. These results demonstrate the feasibility of using a short-arm centrifuge for mouse experiments.

Feasibility of a Short-Arm Centrifuge for Mouse Hypergravity Experiments

PubMed Central

Morita, Hironobu; Obata, Koji; Abe, Chikara; Shiba, Dai; Shirakawa, Masaki; Kudo, Takashi; Takahashi, Satoru

2015-01-01

To elucidate the pure impact of microgravity on small mammals despite uncontrolled factors that exist in the International Space Station, it is necessary to construct a 1 g environment in space. The Japan Aerospace Exploration Agency has developed a novel mouse habitat cage unit that can be installed in the Cell Biology Experiment Facility in the Kibo module of the International Space Station. The Cell Biology Experiment Facility has a short-arm centrifuge to produce artificial 1 g gravity in space for mouse experiments. However, the gravitational gradient formed inside the rearing cage is larger when the radius of gyration is shorter; this may have some impact on mice. Accordingly, biological responses to hypergravity induced by a short-arm centrifuge were examined and compared with those induced by a long-arm centrifuge. Hypergravity induced a significant Fos expression in the central nervous system, a suppression of body mass growth, an acute and transient reduction in food intake, and impaired vestibulomotor coordination. There was no difference in these responses between mice raised in a short-arm centrifuge and those in a long-arm centrifuge. These results demonstrate the feasibility of using a short-arm centrifuge for mouse experiments. PMID:26221724

Structural, Electronic and Vibrational Properties of Nax Si 136(0 < x < 24) Clathrates

NASA Astrophysics Data System (ADS)

Higgins, Craig; Nenghabi, Emmanuel; Myles, Charles; Biswas, Koushik; Beekman, Matt; Nolas, George

2011-03-01

CRAIG HIGGINS, EMMANUEL NENGHA BI† , CHARLES W. MYLES, Texas Tech U.; KOUSHIK BISWAS, Oak Ridge National Lab; MATT BEEKMAN, U. of Oregon; GEORGE S. NOLAS, U. of South Florida - Na x Si 136 is a Type II clathrate with important thermoelectric properties. It's face-centered cubic lattice contains polyhedral ``cages'' of silicon atoms with Na atom ``guests'' in the cages. This material is very interesting because powder X-ray diffraction experiments 1 for differing Na content x have shown that, for increasing x in the range 0

Polyetheretherketone (PEEK) intervertebral cage as a cause of chronic systemic allergy: a case report.

PubMed

Maldonado-Naranjo, Andres L; Healy, Andrew T; Kalfas, Iain H

2015-07-01

Polyetheretherketone (PEEK) is an organic polymer thermoplastic with strong mechanical and chemical resistance properties. It has been used in industry to fabricate items for demanding applications such as bearings, piston parts, compressor plate valves, and cable insulation. Since the early 1980s, polyetheretherketone polymers have been increasingly used in orthopedic and spinal surgery applications. Numerous studies and years of clinical experience have confirmed the biocompatibility of this material. The purpose of the study was to report a case of chronic systemic allergy after anterior cervical decompression and fusion (ACDF) and implantation of an intervertebral PEEK cage, with resolution of symptoms after removal of PEEK cage. This study is a case report with clinical evidence for allergy to PEEK. The methods involve clinical findings and review of current literature. After ACDF and implantation of an intervertebral PEEK cage, the patient had developed an angioedema-like picture marked by severe redness, itching, swelling of his tongue, and skin thickening. A skin patch test was positive for PEEK. Removal of the implant resulted in the resolution of his allergy symptoms shortly after surgery. Tissue reactions to PEEK are extremely rare. Herein, we present the first report of a chronic allergic response to interbody PEEK material. Copyright © 2015 Elsevier Inc. All rights reserved.

Activite locomotrice de souris isolees, de deux lignees consanguines, dans un environnement semi-naturel ou en cages d'elevage.

PubMed

Le Pape, G; Lassalle, J M

1979-10-01

Des enregistrements continus d'activité locomotrice ont été effectués sur des souris mâles isolées des lignées Balb/c et C57bl/6, vivant en cages d'élevage ou en milieu semi- naturel. Les résultats montrent que les différences entre ces deux situations ne sont pas perçues de la même façon par les animaux des deux lign'ees: alors qu'en cages d'élevage les souris des deux lignées experiment la même quantité totale d'activaté, en milieu semi-naturel les souris Balb/c sont plus actives que les C57bl/6. En outre, l≐s différences observées entre les lignées pour la repartition de l'activité au cours du nycthèmere s'inversent lorsque l'on passe d'une situation à l'autre. L'étude de la variabilité fait aparaître une dispersion plus grande des performances dans la lignée C57bl/6 en cages d'élevage, alors qu'en milieu semi-naturel la dispersion est plus chez Bal/c. Copyright © 1979. Published by Elsevier B.V.

Characterization of a new caged proton capable of inducing large pH jumps.

PubMed Central

Barth, Andreas; Corrie, John E T

2002-01-01

A new caged proton, 1-(2-nitrophenyl)ethyl sulfate (caged sulfate), is characterized by infrared spectroscopy and compared with a known caged, proton 2-hydroxyphenyl 1-(2-nitrophenyl)ethyl phosphate (caged HPP). In contrast to caged HPP, caged sulfate can induce large pH jumps and protonate groups that have pK values as low as 2.2. The photolysis mechanism of caged sulfate is analogous to that of P(3)-[1-(2-nitrophenyl)ethyl] ATP (caged ATP), and the photolysis efficiency is similar. The utility of this new caged compound for biological studies was demonstrated by its ability to drive the acid-induced conformational change of metmyoglobin. This transition from the native conformation to a partially unfolded form takes place near pH 4 and was monitored by near-UV absorption spectroscopy. PMID:12414718

Effect of intravenous endotoxin on blood cell profiles of broilers housed in cages and floor litter environments.

PubMed

Wang, W; Wideman, R F; Chapman, M E; Bersi, T K; Erf, G F

2003-12-01

Commercial broilers are constantly exposed to airborne microorganisms and endotoxin (lipopolysaccharide, LPS). It has been shown that microbial contamination of the air was higher in broiler houses using floor litter than in broiler houses using netting-type floors. The current study evaluated the effect of housing conditions on blood leukocyte profiles and tested the hypothesis that, when compared to broilers reared in clean stainless steel cages (Cage group), broilers raised on floor litter (Floor group) should experience a higher environmental challenge and have a desensitized immune system that may exhibit better tolerance/resistance to subsequent intravenous LPS challenge. Hematological parameters were evaluated prior to and following i.v. administration of 1 mg/kg BW Salmonella typhimurium LPS (dissolved at 1 mg/0.25 mL in PBS) or i.v. injection of 0.25 mL/kg BW PBS alone. The results showed that prior to LPS/PBS injection, broilers in the cage group had higher heterophil and monocyte concentrations, a higher B cell percentage within the lymphocyte population, and a higher heterophil to lymphocyte (H:L) ratio in the blood. The i.v. LPS injection resulted in 25% mortality in the cage group and 42% mortality in the floor group within 8 h post-injection. LPS reduced the concentrations of total white blood cells (WBC) and all differential WBC except eosinophils and increased thrombocyte concentrations within 1 h post-injection in both groups. All of these values returned to their respective pre-injection levels within 48 h post-injection in the surviving birds. The two groups exhibited similar overall hematological changes after LPS injection except that the cage group showed a higher H:L ratio at 8 h post-injection and a lower B-cell percentage within the lymphocyte population at 48 h post-injection when compared with the floor group. We concluded that the immune systems of broilers reared on floor litter were desensitized and exhibited less pronounced leukocyte responses to i.v. LPS when compared with those of broilers reared in clean stainless steel cages. However, such desensitization of the immune system did not help broilers survive subsequent i.v. LPS challenge.

The challenge of pelvic discontinuity: cup-cage reconstruction does better than conventional cages in mid-term.

PubMed

Abolghasemian, M; Tangsaraporn, S; Drexler, M; Barbuto, R; Backstein, D; Safir, O; Kuzyk, P; Gross, A

2014-02-01

The use of ilioischial cage reconstruction for pelvic discontinuity has been replaced by the Trabecular Metal (Zimmer, Warsaw, Indiana) cup-cage technique in our institution, due to the unsatisfactory outcome of using a cage alone in this situation. We report the outcome of 26 pelvic discontinuities in 24 patients (20 women and four men, mean age 65 years (44 to 84)) treated by the cup-cage technique at a mean follow-up of 82 months (12 to 113) and compared them with a series of 19 pelvic discontinuities in 19 patients (18 women and one man, mean age 70 years (42 to 86)) treated with a cage at a mean follow-up of 69 months (1 to 170). The clinical and radiological outcomes as well as the survivorship of the groups were compared. In all, four of the cup-cage group (15%) and 13 (68%) of the cage group failed due to septic or aseptic loosening. The seven-year survivorship was 87.2% (95% confidence interval (CI) 71 to 103) for the cup-cage group and 49.9% (95% CI 15 to 84) for the cage-alone group (p = 0.009). There were four major complications in the cup-cage group and nine in the cage group. Radiological union of the discontinuity was found in all successful cases in the cup-cage group and three of the successful cage cases. Three hips in the cup-cage group developed early radiological migration of the components, which stabilised with a successful outcome. Cup-cage reconstruction is a reliable technique for treating pelvic discontinuity in mid-term follow-up and is preferred to ilioischial cage reconstruction. If the continuity of the bone graft at the discontinuity site is not disrupted, early migration of the components does not necessarily result in failure.

Assembly and structural analysis of a covalently closed nano-scale DNA cage

PubMed Central

Andersen, Felicie F.; Knudsen, Bjarne; Oliveira, Cristiano Luis Pinto; Frøhlich, Rikke F.; Krüger, Dinna; Bungert, Jörg; Agbandje-McKenna, Mavis; McKenna, Robert; Juul, Sissel; Veigaard, Christopher; Koch, Jørn; Rubinstein, John L.; Guldbrandtsen, Bernt; Hede, Marianne S.; Karlsson, Göran; Andersen, Anni H.; Pedersen, Jan Skov; Knudsen, Birgitta R.

2008-01-01

The inherent properties of DNA as a stable polymer with unique affinity for partner molecules determined by the specific Watson–Crick base pairing makes it an ideal component in self-assembling structures. This has been exploited for decades in the design of a variety of artificial substrates for investigations of DNA-interacting enzymes. More recently, strategies for synthesis of more complex two-dimensional (2D) and 3D DNA structures have emerged. However, the building of such structures is still in progress and more experiences from different research groups and different fields of expertise are necessary before complex DNA structures can be routinely designed for the use in basal science and/or biotechnology. Here we present the design, construction and structural analysis of a covalently closed and stable 3D DNA structure with the connectivity of an octahedron, as defined by the double-stranded DNA helices that assembles from eight oligonucleotides with a yield of ∼30%. As demonstrated by Small Angle X-ray Scattering and cryo-Transmission Electron Microscopy analyses the eight-stranded DNA structure has a central cavity larger than the apertures in the surrounding DNA lattice and can be described as a nano-scale DNA cage, Hence, in theory it could hold proteins or other bio-molecules to enable their investigation in certain harmful environments or even allow their organization into higher order structures. PMID:18096620

Host group formation decreases exposure to vector-borne disease: a field experiment in a 'hotspot' of West Nile virus transmission.

PubMed

Krebs, Bethany L; Anderson, Tavis K; Goldberg, Tony L; Hamer, Gabriel L; Kitron, Uriel D; Newman, Christina M; Ruiz, Marilyn O; Walker, Edward D; Brawn, Jeffrey D

2014-12-07

Animals can decrease their individual risk of predation by forming groups. The encounter-dilution hypothesis extends the potential benefits of gregariousness to biting insects and vector-borne disease by predicting that the per capita number of insect bites should decrease within larger host groups. Although vector-borne diseases are common and can exert strong selective pressures on hosts, there have been few tests of the encounter-dilution effect in natural systems. We conducted an experimental test of the encounter-dilution hypothesis using the American robin (Turdus migratorius), a common host species for the West Nile virus (WNV), a mosquito-borne pathogen. By using sentinel hosts (house sparrows, Passer domesticus) caged in naturally occurring communal roosts in the suburbs of Chicago, we assessed sentinel host risk of WNV exposure inside and outside of roosts. We also estimated per capita host exposure to infected vectors inside roosts and outside of roosts. Sentinel birds caged inside roosts seroconverted to WNV more slowly than those outside of roosts, suggesting that social groups decrease per capita exposure to infected mosquitoes. These results therefore support the encounter-dilution hypothesis in a vector-borne disease system. Our results suggest that disease-related selective pressures on sociality may depend on the mode of disease transmission. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Reproductive Performance of Mice in Disposable and Standard Individually Ventilated Cages

PubMed Central

Ferguson, Danielle R; Bailey, Michele M

2013-01-01

This study assessed the reproductive performance of mice housed in 2 types of individually ventilated caging systems. Breeding pairs from 48 female and 24 male mice of 3 established transgenic mouse breeding colonies were placed in either a standard or disposable ventilated caging system. For 3 breeding cycles, the number of pups born, pup survival rate to weaning, time interval between litters, and pup weights were monitored for each breeding pair. Disposable and standard cages were maintained in the same location during breeding. Environmental parameters included intracage temperature, humidity, and ammonia and carbon dioxide levels and room light intensity and sound. Overall, 776 offspring were produced. Breeding performance did not differ significantly between the 2 cage types. By 11 wk of age, the weights of pups from both cage types were equivalent. The intracage temperature was 1.1 °F warmer and light intensity at the site of the nest was 34 lx dimmer in disposable cages than in standard caging. The difference in lighting likely was due to nest location; the nests in the disposable cages were at the back of the cages and away from the anterior air supply, whereas in standard caging, nests were at the front of the cages, with the air supply at the rear. Under these husbandry conditions, mice housed in disposable caging systems have comparable breeding performance to those housed in standard individually ventilated cages. PMID:23849403

The temporal dynamics of the effects of monoacylglycerol lipase blockade on locomotion, anxiety, and body temperature.

PubMed

Aliczki, Mano; Balogh, Zoltan; Tulogdi, Aron; Haller, Jozsef

2012-08-01

Studies with the monoacylglycerol lipase blocker JZL184 have suggested that enhanced 2-arachidonoylglycerol signaling suppresses locomotion, lowers body temperature, and decreases anxiety. Although the neurochemical effects of JZL184 develop within 30 min, its behavioral and autonomic effects have been studied much later. To clarify temporal dynamics, we studied the effects of intraperitoneal injections of JZL184 in mice on home-cage locomotion and body temperature for 120 min using in-vivo biotelemetry. We also studied the effects of 4, 8, and 16 mg/kg JZL184 in the open field and elevated plus maze at various time points. In the home cage, JZL184 blunted injection-induced body temperature increases but exerted no long-term effects. Vehicle injections increased the duration of rapid movements whereas the duration of motionless periods was decreased, a pattern also abolished by JZL184. Although the highest dose exerted a mild long-term effect on the relative duration of motionless periods, JZL184 seemed to have phasic rather than tonic effects in the home cage. By contrast, open field and plus maze behavior was affected 80 and 120 min but not 40 min after treatments, which may indicate tonic rather than phasic effects in these tests. Our findings confirm earlier reports of a mild anxiolytic effect of JZL184, but surprisingly, the compound markedly and dose dependently increased locomotion in the open field in both CD1 and C57BL/6J mice. These findings are difficult to reconcile at present, but suggest that the effects of monoacylglycerol lipase inhibition are more complex than previously believed and may depend strongly on as yet unidentified factors such as environmental conditions, the time of testing, species/strains, etc.

Exclusive photorelease of signalling lipids at the plasma membrane.

PubMed

Nadler, André; Yushchenko, Dmytro A; Müller, Rainer; Stein, Frank; Feng, Suihan; Mulle, Christophe; Carta, Mario; Schultz, Carsten

2015-12-21

Photoactivation of caged biomolecules has become a powerful approach to study cellular signalling events. Here we report a method for anchoring and uncaging biomolecules exclusively at the outer leaflet of the plasma membrane by employing a photocleavable, sulfonated coumarin derivative. The novel caging group allows quantifying the reaction progress and efficiency of uncaging reactions in a live-cell microscopy setup, thereby greatly improving the control of uncaging experiments. We synthesized arachidonic acid derivatives bearing the new negatively charged or a neutral, membrane-permeant coumarin caging group to locally induce signalling either at the plasma membrane or on internal membranes in β-cells and brain slices derived from C57B1/6 mice. Uncaging at the plasma membrane triggers a strong enhancement of calcium oscillations in β-cells and a pronounced potentiation of synaptic transmission while uncaging inside cells blocks calcium oscillations in β-cells and causes a more transient effect on neuronal transmission, respectively. The precise subcellular site of arachidonic acid release is therefore crucial for signalling outcome in two independent systems.

Aspects of the Development of Housing for the Spaceflight of Pregnant and Lactating Rats with Neonates

NASA Technical Reports Server (NTRS)

Hinds, William E.; Mayer, David J.; Evans, Juli; Spratt, Shahn; Lane, Philip K.; Rodriguez, Shari L.; Navidi, Meena; Armstrong, Rachel; Lemos, Bonnie; Dalton, Bonnie P. (Technical Monitor)

1996-01-01

Recent and upcoming spaceflights are investigating the effect of weightlessness on developing neural and organ systems. Pregnant rats and dams with neonates have to be accommodated in cages that support the special requirements of these animals. Extensive ground testing of cage concepts, the effect of launch and landing stresses on the maintenance of pregnancy and maternal behavior at different neonatal ages, and techniques for monitoring adaptability to change are discussed. A spaceflight opportunity for the NlH.R3 payload of rat families at three different postnatal ages demonstrated that the survival of very young animals was not good but that older newborns could be returned to Earth in reasonably good health. The development of cages for the Research Animal Holding Facility (RAHF) to support the flight of neonates on Neurolab was continued and incorporated modifications that were demonstrated by the NIH.R3 flight. Other modifications to the RAHF are discussed. Data from biocompatibility and experiment verification testing are presented.

Femtosecond Laser Microfabrication of an Integrated Device for Optical Release and Sensing of Bioactive Compounds

PubMed Central

Ghezzi, Diego; Vazquez, Rebeca Martinez; Osellame, Roberto; Valtorta, Flavia; Pedrocchi, Alessandra; Valle, Giuseppe Della; Ramponi, Roberta; Ferrigno, Giancarlo; Cerullo, Giulio

2008-01-01

Flash photolysis of caged compounds is one of the most powerful approaches to investigate the dynamic response of living cells. Monolithically integrated devices suitable for optical uncaging are in great demand since they greatly simplify the experiments and allow their automation. Here we demonstrate the fabrication of an integrated bio-photonic device for the optical release of caged compounds. Such a device is fabricated using femtosecond laser micromachining of a glass substrate. More in detail, femtosecond lasers are used both to cut the substrate in order to create a pit for cell growth and to inscribe optical waveguides for spatially selective uncaging of the compounds present in the culture medium. The operation of this monolithic bio-photonic device is tested using both free and caged fluorescent compounds to probe its capability of multipoint release and optical sensing. Application of this device to the study of neuronal network activity can be envisaged. PMID:27873888

Interactions of Amphibians, Fish, and Macroinvertebrates in a Southeastern Wetland

NASA Astrophysics Data System (ADS)

Schultheis, R. D.; Batzer, D. P.

2005-05-01

In fishless habitats, amphibians often compete with and are predators of macroinvertebrates. Unlike fish, the effects these interactions have on macroinvertebrate communities have been largely unexplored. We conducted an experiment in a semi-permanent oxbow wetland in the Piedmont region of Georgia to explore interactions between amphibians and macroinvertebrates. The predator community was dominated by Ambystoma opacum (Marbled Salamander) and Notophthalmus viridescens (Eastern Newt). Salamanders and newts were excluded from areas of wetland habitat using wire mesh cages (1.5M x 1.5M, 3mm mesh). The macroinvertebrate communities within the cages were then compared to the ambient habitat outside the cages. Fish, mostly Lepomis macrochirus (Bluegill) and Gambusia affinis (Mosquito Fish), colonized the wetland late in the first year of the study, and became common by year two. Also in year two, Rana catesbeiana (Bullfrog) became established. Thus, we were able to explore the variable effects on the macroinvertebrate community of a changing predator complex over a two year period.

Home-cage odors spatial cues elicit theta phase/gamma amplitude coupling between olfactory bulb and dorsal hippocampus.

PubMed

Pena, Roberta Ribas; Medeiros, Daniel de Castro; Guarnieri, Leonardo de Oliveira; Guerra, Julio Boriollo; Carvalho, Vinícius Rezende; Mendes, Eduardo Mazoni Andrade Marçal; Pereira, Grace Schenatto; Moraes, Márcio Flávio Dutra

2017-11-05

The brain oscillations may play a critical role in synchronizing neuronal assemblies in order to establish appropriate sensory-motor integration. In fact, studies have demonstrated phase-amplitude coupling of distinct oscillatory rhythms during cognitive processes. Here we investigated whether olfacto-hippocampal coupling occurs when mice are detecting familiar odors located in a spatially restricted area of a new context. The spatial olfactory task (SOT) was designed to expose mice to a new environment in which only one quadrant (target) contains odors provided by its own home-cage bedding. As predicted, mice showed a significant higher exploration preference to the target quadrant; which was impaired by olfactory epithelium lesion (ZnSO 4 ). Furthermore, mice were able to discriminate odors from a different cage and avoided the quadrant with predator odor 2,4,5-trimethylthiazoline (TMT), reinforcing the specificity of the SOT. The local field potential (LFP) analysis of non-lesioned mice revealed higher gamma activity (35-100Hz) in the main olfactory bulb (MOB) and a significant theta phase/gamma amplitude coupling between MOB and dorsal hippocampus, only during exploration of home-cage odors (i.e. in the target quadrant). Our results suggest that exploration of familiar odors in a new context involves dynamic coupling between the olfactory bulb and dorsal hippocampus. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Morphological plasticity in the tropical sponge Anthosigmella varians: responses to predators and wave energy.

PubMed

Hill, Malcolm S; Hill, April L

2002-02-01

The goal of the research presented here was to examine phenotypic plasticity exhibited by three morphotypes of the common Caribbean sponge Anthosigmella varians (Duchassaing & Michelotti). We were interested in examining the biotic (and, to a lesser extent, abiotic) factors responsible for branch production in this species. We also tested the hypothesis that the skeleton may serve an antipredator function in this sponge, focusing on vertebrate fish predators (i.e., angelfish) in this work. In transplant and caging experiments, unprotected forma varians replicates were immediately consumed by angelfish, while caged replicates persisted on the reef for several months. These findings support the hypothesis that predators (and not wave energy) restrict forma varians to lagoonal habitats. Branch production was not observed in A. varians forma incrustans when sponges were protected from predators or placed in predator-free, low-wave-energy environments. It is not clear from our work whether forma incrustans is capable of producing branches (i.e., whether branch production is a plastic trait in this morph). Additional field experiments demonstrated that A. varians forma varians increased spicule concentrations, compared to uninjured sponges, in response to artificial predation events, and A. varians forma rigida reduced spicule concentrations, compared to uncaged controls, when protected from predators. These findings indicate that spicule concentration is a plastic morphological trait that can be induced by damage, and that A. varians may be able to reduce spicule concentrations when environmental conditions change (e.g., in the absence of predators). The potential significance of inducible defenses and structural anti-predator defenses in sponges is discussed in relation to recent work on sponge chemical defenses.

Advanced behavioural screening: automated home cage ethology.

PubMed

Spruijt, Berry M; DeVisser, Leonie

2006-01-01

Animal behaviour has been studied using two approaches, (1) well-controlled experiments focusing on specific responses and (2) those with natural - fuzzy - but biologically relevant conditions. Ideally, one behavioural test should be able to address both. The home cage provided with various stimuli is proposed as an all-in-one possibility. This, however, results in an exponential increase in complexity regarding observation and analysis tools. It seems difficult to accept that behavioural expressions need a mathematical approach to unravel its organisation and meaning. Developments in artificial intelligence and data mining are essential to accelerate this necessary evolution in behavioural sciences.: � 2006 Elsevier Ltd . All rights reserved.

Long-term effects of placing one or two cages in instrumented posterior lumbar interbody fusion.

PubMed

Zhang, Mingzheng; Pu, Fang; Xu, Liqiang; Zhang, Linlin; Yao, Jie; Li, Deyu; Wang, Yu; Fan, Yubo

2016-06-01

Posterior lumbar interbody fusion (PLIF) is an established surgical procedure for spine stabilization after the removal of an intervertebral disc. Researches have shown that inserting a single oblique cage has a similar immediate effect to coupled cages, and it has been proposed that single-cage PLIF is a useful alternative to traditional two-cage PLIF. However, it is not clear whether placing one or two cages represents the best choice for long-term fusion. The aim of this study is to examine how cage placement affects bone remodeling after PLIF surgery, and how this consequently impacts the long-term fusion process. A finite element model of a L3-L4 lumbar spine with PLIF was developed. The spinal segment was modeled with a partial laminectomy and a discectomy with partial facetectomy, and implanted with posterior pedicle screws. Two models were analyzed, one with coupled parallel cages and one with a single oblique cage. Adaptive bone remodeling was simulated according to Huiskes' criterion. The results showed that in the initial state prior to any bone remodeling, cage stress, cage subsidence and cage dislodgement in the single cage model were all greater than in the coupled cage model. In the final state after significant bone remodeling had taken place, these parameters had decreased in both models and the differences between the two models were reduced. Also, the single cage model demonstrated superior bone development in the bone graft when placed under a constant 400 N axial compressive load. Based on the long-term results, instrumented PLIF with a single cage could also be encouraged in clinical practice.

Influence of 5 Different Caging Types and the Use of Cage-Changing Stations on Mouse Allergen Exposure

PubMed Central

Feistenauer, Susan; Sander, Ingrid; Schmidt, Jörg; Zahradnik, Eva; Raulf, Monika; Brielmeier, Markus

2014-01-01

Animal allergens constitute a serious health risk in laboratory animal facilities. To assess possibilities for allergen reduction by technical and organizational measures, we studied personnel exposure to mouse urinary aeroallergens in an animal facility with a holding capacity of 30,000 cages. Short-term (2 h) and intermediate-term (12 h) stationary samples (n = 107) and short-term (2 h) personnel samples (n = 119) were collected on polytetrafluorethylene filters by using air pumps. Long-term (14 d) stationary dust samples containing airborne allergens (n = 165) were collected with electrostatic dust fall collectors (EDC). Mouse allergens were quantified by ELISA. Personnel samples were collected during bedding disposal and refilling of clean cages as well as during cage changing with and without use of cage-changing station. Animal rooms were equipped with either open cages, cages with a soft filter top, cages with a rigid filter top (static microisolation caging), or with individually ventilated cages (IVC) with either a sealed or nonsealed lid, each in positive- or negative-pressure mode. Highest personnel allergen exposure was detected during cage change and emptying of soiled cages. Allergen concentrations were lowest in rooms with sealed IVC under positive or negative pressure, with unsealed IVC under negative pressure, and with static microisolation caging. The use of cage-changing stations and a vacuum bedding-disposal system reduced median personnel exposures 14- to 25-fold, respectively. Using sealed IVC and changing stations minimized allergen exposure, indicating that state-of-the-art equipment reduces exposure to mouse allergens and decreases health risks among animal facility personnel. PMID:25199090

The Effects of Context Extinction on US Signal Value

ERIC Educational Resources Information Center

Goddard Murray J.

2007-01-01

Two experiments with rats examined the effects of context extinction on responding to the signal value of an unconditioned stimulus (US). In Experiment 1, US signal value was first trained when a single food pellet signaled the delivery of three additional pellets. After training, rats received either context extinction (CE) or home cage (HC)…

Stress indicator gene expression profiles, colony dynamics and tissue development of honey bees exposed to sub-lethal doses of imidacloprid in laboratory and field experiments.

PubMed

De Smet, Lina; Hatjina, Fani; Ioannidis, Pavlos; Hamamtzoglou, Anna; Schoonvaere, Karel; Francis, Frédéric; Meeus, Ivan; Smagghe, Guy; de Graaf, Dirk C

2017-01-01

In this study, different context-dependent effects of imidacloprid exposure on the honey bee response were studied. Honey bees were exposed to different concentrations of imidacloprid during a time period of 40 days. Next to these variables, a laboratory-field comparison was conducted. The influence of the chronic exposure on gene expression levels was determined using an in-house developed microarray targeting different immunity-related and detoxification genes to determine stress-related gene expression changes. Increased levels of the detoxification genes encoding, CYP9Q3 and CYT P450, were detected in imidacloprid-exposed honey bees. The different context-dependent effects of imidacloprid exposure on honey bees were confirmed physiologically by decreased hypopharyngeal gland sizes. Honey bees exposed to imidacloprid in laboratory cages showed a general immunosuppression and no detoxification mechanisms were triggered significantly, while honey bees in-field showed a resilient response with an immune stimulation at later time points. However, the treated colonies had a brood and population decline tendency after the first brood cycle in the field. In conclusion, this study highlighted the different context-dependent effects of imidacloprid exposure on the honey bee response. These findings warn for possible pitfalls concerning the generalization of results based on specific experiments with short exposure times. The increased levels of CYT P450 and CYP9Q3 combined with an immune response reaction can be used as markers for bees which are exposed to pesticides in the field.

Stress indicator gene expression profiles, colony dynamics and tissue development of honey bees exposed to sub-lethal doses of imidacloprid in laboratory and field experiments

PubMed Central

Ioannidis, Pavlos; Hamamtzoglou, Anna; Schoonvaere, Karel; Francis, Frédéric; Meeus, Ivan; Smagghe, Guy; de Graaf, Dirk C.

2017-01-01

In this study, different context-dependent effects of imidacloprid exposure on the honey bee response were studied. Honey bees were exposed to different concentrations of imidacloprid during a time period of 40 days. Next to these variables, a laboratory-field comparison was conducted. The influence of the chronic exposure on gene expression levels was determined using an in-house developed microarray targeting different immunity-related and detoxification genes to determine stress-related gene expression changes. Increased levels of the detoxification genes encoding, CYP9Q3 and CYT P450, were detected in imidacloprid-exposed honey bees. The different context-dependent effects of imidacloprid exposure on honey bees were confirmed physiologically by decreased hypopharyngeal gland sizes. Honey bees exposed to imidacloprid in laboratory cages showed a general immunosuppression and no detoxification mechanisms were triggered significantly, while honey bees in-field showed a resilient response with an immune stimulation at later time points. However, the treated colonies had a brood and population decline tendency after the first brood cycle in the field. In conclusion, this study highlighted the different context-dependent effects of imidacloprid exposure on the honey bee response. These findings warn for possible pitfalls concerning the generalization of results based on specific experiments with short exposure times. The increased levels of CYT P450 and CYP9Q3 combined with an immune response reaction can be used as markers for bees which are exposed to pesticides in the field. PMID:28182641

Structures, Energetics and Spectroscopic Fingerprints of Water Clusters n=2-24

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

Yoo, Soohaeng; Xantheas, Sotiris S.

This chapter discusses the structures, energetics, and vibrational spectra of the first few (n$24) water clusters obtained from high-level electronic structure calculations. The results are discussed in the perspective of being used to parameterize/assess the accuracy of classical and quantum force fields for water. To this end, a general introduction with the classification of those force fields is presented. Several low-lying families of minima for the medium cluster sizes are considered. The transition from the “all surface” to the “fully coordinated” cluster structures occurring at nD17 and its spectroscopic signature is presented. The various families of minima for nD20 aremore » discussed together with the low energy networks of the pentagonal dodecahedron (H2O)20 water cage. Finally, the low-energy networks of the tetrakaidecahedron (T-cage) (H2O)24 cluster are shown and their significance in the construction of periodic lattices of structure I (sI) of the hydrate lattices is discussed.« less

Evaluation of Using Caged Clams to Monitor Contaminated Groundwater Exposure in the Near-Shore Environment of the Hanford Site 300 Area

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

Larson, Kyle B.; Poston, Ted M.; Tiller, Brett L.

2008-01-31

The Asiatic clam (Corbicula fluminea) has been identified as an indicator species for locating and monitoring contaminated groundwater in the Columbia River. Pacific Northwest National Laboratory conducted a field study to explore the use of caged Asiatic clams to monitor contaminated groundwater upwelling in the 300 Area near-shore environment and assess seasonal differences in uranium uptake in relation to seasonal flow regimes of the Columbia River. Additional objectives included examining the potential effects of uranium accumulation on growth, survival, and tissue condition of the clams. This report documents the field conditions and procedures, laboratory procedures, and statistical analyses used inmore » collecting samples and processing the data. Detailed results are presented and illustrated, followed by a discussion comparing uranium concentrations in Asiatic clams collected at the 300 Area and describing the relationship between river discharge, groundwater indicators, and uranium in clams. Growth and survival, histology, and other sources of environmental variation also are discussed.« less

The Impact of Epifaunal Predation on the Structure of Macroinfaunal Invertebrate Communities of Tidal Saltmarsh Creeks

NASA Astrophysics Data System (ADS)

Sardá, R.; Foreman, K.; Werme, C. E.; Valiela, I.

1998-05-01

The impact of epibenthic predators foraging on macroinfaunal communities was analysed in Great Sippewissett salt marsh (MA, U.S.A.) by installing experimental cages in the most productive sediments of the marsh (77 g dry weight m -2year -1). The most productive macroinfaunal species in these sediments were Marenzelleria viridis(43·1 g dry weight m -2year -1) Heteromastus filiformis(13·7 g dry weight m -2year -1) and Neanthes arenaceodonta(7·6 g dry weight m -2year -1). Macroinfaunal densities peaked in June following the spring recruitment. Density and biomass inside the cages were significantly higher during the growing season, however, density declined in July and August following the seasonal cycle observed outside cages, while biomass did not suffer this decline. The absence of epibenthic predators favored growth and accumulation of larger organisms, especially M. viridis, and included higher presence of predaceous infauna ( Glycera americana, Neanthes succinea, Neanthes virens, Eteone heteropodaand Nemerteans). At the end of the experiment, there was 22·2 g dry weight m -2more macroinfaunal biomass in the complete cages than in ambient sediments. The absence of epibenthic predators also increased secondary production; M. viridisdoubled production in the sediments inside cages compared with outside cages. The most common benthic predaceous fishes in the marsh were the killifishes, Fundulus heteroclitusand Fundulus majalis, and some seasonal invasive fishes ( Gasterosteus aculeatus, Tautoga onitis, Centropristes striatusand Pleuronectes americanus). While invasive fishes preyed mainly on benthic invertebrates and grew faster, resident fishes shifted their diets through the season. The values of macroinfaunal secondary production obtained in these sediments can support the energy requirements of the predators of the marsh; in this way the pulse of secondary production created by the macroinfaunal populations travels up the saltmarsh food web.

Three-dimensional light trap for reflective particles

DOEpatents

Neal, Daniel R.

1999-01-01

A system for containing either a reflective particle or a particle having an index of refraction lower than that of the surrounding media in a three-dimensional light cage. A light beam from a single source illuminates an optics system and generates a set of at least three discrete focussed beams that emanate from a single exit aperture and focus on to a focal plane located close to the particle. The set of focal spots defines a ring that surrounds the particle. The set of focussed beams creates a "light cage" and circumscribes a zone of no light within which the particle lies. The surrounding beams apply constraining forces (created by radiation pressure) to the particle, thereby containing it in a three-dimensional force field trap. A diffractive element, such as an aperture multiplexed lens, or either a Dammann grating or phase element in combination with a focusing lens, may be used to generate the beams. A zoom lens may be used to adjust the size of the light cage, permitting particles of various sizes to be captured and contained.

Three-dimensional light trap for reflective particles

DOEpatents

Neal, D.R.

1999-08-17

A system is disclosed for containing either a reflective particle or a particle having an index of refraction lower than that of the surrounding media in a three-dimensional light cage. A light beam from a single source illuminates an optics system and generates a set of at least three discrete focused beams that emanate from a single exit aperture and focus on to a focal plane located close to the particle. The set of focal spots defines a ring that surrounds the particle. The set of focused beams creates a ``light cage`` and circumscribes a zone of no light within which the particle lies. The surrounding beams apply constraining forces (created by radiation pressure) to the particle, thereby containing it in a three-dimensional force field trap. A diffractive element, such as an aperture multiplexed lens, or either a Dammann grating or phase element in combination with a focusing lens, may be used to generate the beams. A zoom lens may be used to adjust the size of the light cage, permitting particles of various sizes to be captured and contained. 10 figs.

High-Temperature unfolding of a trp-Cage mini-protein: a molecular dynamics simulation study

PubMed Central

Seshasayee, Aswin Sai Narain

2005-01-01

Background Trp cage is a recently-constructed fast-folding miniprotein. It consists of a short helix, a 3,10 helix and a C-terminal poly-proline that packs against a Trp in the alpha helix. It is known to fold within 4 ns. Results High-temperature unfolding molecular dynamics simulations of the Trp cage miniprotein have been carried out in explicit water using the OPLS-AA force-field incorporated in the program GROMACS. The radius of gyration (Rg) and Root Mean Square Deviation (RMSD) have been used as order parameters to follow the unfolding process. Distributions of Rg were used to identify ensembles. Conclusion Three ensembles could be identified. While the native-state ensemble shows an Rg distribution that is slightly skewed, the second ensemble, which is presumably the Transition State Ensemble (TSE), shows an excellent fit. The denatured ensemble shows large fluctuations, but a Gaussian curve could be fitted. This means that the unfolding process is two-state. Representative structures from each of these ensembles are presented here. PMID:15760474

Flexibility and fatigue evaluation of oblique as compared with anterior lumbar interbody cages with integrated endplate fixation.

PubMed

Freeman, Andrew L; Camisa, William J; Buttermann, Glenn R; Malcolm, James R

2016-01-01

This study was undertaken to quantify the in vitro range of motion (ROM) of oblique as compared with anterior lumbar interbody devices, pullout resistance, and subsidence in fatigue. Anterior and oblique cages with integrated plate fixation (IPF) were tested using lumbar motion segments. Flexibility tests were conducted on the intact segments, cage, cage + IPF, and cage + IPF + pedicle screws (6 anterior, 7 oblique). Pullout tests were then performed on the cage + IPF. Fatigue testing was conducted on the cage + IPF specimens for 30,000 cycles. No ROM differences were observed in any test group between anterior and oblique cage constructs. The greatest reduction in ROM was with supplemental pedicle screw fixation. Peak pullout forces were 637 ± 192 N and 651 ± 127 N for the anterior and oblique implants, respectively. The median cage subsidence was 0.8 mm and 1.4 mm for the anterior and oblique cages, respectively. Anterior and oblique cages similarly reduced ROM in flexibility testing, and the integrated fixation prevented device displacement. Subsidence was minimal during fatigue testing, most of which occurred in the first 2500 cycles.

Marked dissociation between hypothalamic-pituitary-adrenal activation and long-term behavioral effects in rats exposed to immobilization or cat odor.

PubMed

Muñoz-Abellán, C; Andero, R; Nadal, R; Armario, A

2008-09-01

Exposure of rodents to cats or certain cat odors results in long-term behavioral effects reminiscent of enhanced anxiety that have been considered to model post-traumatic stress disorder. However, other severe stressors such as tail-shock or immobilization in wooden boards (IMO) appear to induce shorter lasting changes in anxiety. In addition, there are controversial results regarding the effects of urine/feces odors. In the present work, we studied in two experiments the relationship between the degree of stress experienced by the animals during exposure to IMO, urine odors or fur odors (as assessed by hypothalamic-pituitary-adrenal activation and plasma glucose) and the short- and long-term behavioral consequences. In the first experiment, rats were individually exposed for 15 min to a novel environment (white large cages) containing either clean cat litter (controls) or litter soiled by cats (urine odors). Half of the rats in each condition were left to freely explore the environment whereas the others were subjected to immobilization (IMO) within the cages. Although ACTH, corticosterone and glucose responses to IMO were much stronger than those to the white cages with clean litter or urine odors (which did not differ from each other), no effect of treatments on anxiety-like behavior in the elevated plus-maze (EPM) were found one week later. However, previous IMO exposure did cause sensitization of the ACTH response to the EPM. In the second experiment, the response to white large cages containing either no odor (controls), litter soiled by cats (urine odor) or a cloth impregnated with cat odor (fur odor) was compared. Urine and fur odors elicited similar ACTH and corticosterone responses that were higher than those of controls, but plasma glucose levels were slightly higher in rats exposed to fur odor. When compared to controls, activity was only diminished in the novel cages containing fur odor. Similarly, fur odor-exposed rats, but not those exposed to urine odor, showed signs of enhanced anxiety in the EPM seven days later, although the ACTH response to the EPM was similar in the three groups. The present data demonstrate: (a) a marked dissociation between the degree of ACTH, corticosterone and glucose responses to stressors and their long-term anxiety-like effects; (b) that the type of cat odor is critical in determining the short-term and long-term physiological and behavioral consequences of exposure; and (c) that plasma ACTH released during brief exposure to the EPM does not appear to reflect anxiety-like behavior.

Automated gait analysis in the open-field test for laboratory mice.

PubMed

Leroy, Toon; Silva, Mitchell; D'Hooge, Rudi; Aerts, Jean-Marie; Berckmans, Daniel

2009-02-01

In this article, an automated and accurate mouse observation method, based on a conventional test for motor function evaluation, is outlined. The proposed measurement technique was integrated in a regular open-field test, where the trajectory and locomotion of a free-moving mouse were measured simultaneously. The system setup consisted of a transparent cage and a camera placed below it with its lens pointing upward, allowing for images to be captured from underneath the cage while the mouse was walking on the transparent cage floor. Thus, additional information was obtained about the position of the limbs of the mice for gait reconstruction. In a first step, the camera was calibrated as soon as it was fixed in place. A linear calibration factor, relating distances in image coordinates to real-world dimensions, was determined. In a second step, the mouse was located and its body contour segmented from the image by subtracting a previously taken "background" image of the empty cage from the camera image. In a third step, the movement of the mouse was analyzed and its speed estimated from its location in the past few images. If the speed was above a 1-sec threshold, the mouse was recognized to be running, and the image was further processed for footprint recognition. In a fourth step, color filtering was applied within the recovered mouse region to measure the position of the mouse's paws, which were visible in the image as small pink spots. Paws that were detected at the same location in a number of subsequent images were kept as footprints-that is, paws in contact with the cage floor. The footprints were classified by their position relative to the mouse's outline as corresponding to the front left or right paw or the hind left or right paw. Finally, eight parameters were calculated from the footprint pattern to describe the locomotion of the mouse: right/left overlap, front/hind base, right/left front limb stride, and right/left hind limb stride. As an application, the system was tested using normal mice and mice displaying pentobarbital-induced ataxia. The footprint parameters measured using the proposed system showed differences of 10% to 20% between normal and ataxic mice.

Experimental evidence of a potentially increased thrombo-embolic disease risk by domestic electromagnetic field exposure.

PubMed

Caprani, A; Richert, A; Flaud, P

2004-05-01

We have used the EaHy926 endothelial cell line, able to secrete both pro and anti-aggregant platelet agents, as a model for thrombo-embolic diseases. We experimentally established, by comparing these two secretions with or without a Faraday cage, that the environmental electromagnetic field significantly increases the thrombo-embolic risks in this endothelial cell line. Copyright 2004 Wiley-Liss, Inc.

Effect of long-term (2 years) exposure of mouse brains to global system for mobile communication (GSM) radiofrequency fields on astrocytic immunoreactivity.

PubMed

Court-Kowalski, Stefan; Finnie, John W; Manavis, Jim; Blumbergs, Peter C; Helps, Stephen C; Vink, Robert

2015-04-01

This study was designed to determine whether long-term (2 years) brain exposure to mobile telephone radiofrequency (RF) fields produces any astrocytic activation as these glia react to a wide range of neural perturbations by astrogliosis. Using a purpose-designed exposure system at 900 MHz, mice were given a single, far-field whole body exposure at a specific absorption rate of 4 W/kg on five successive days per week for 104 weeks. Control mice were sham-exposed or freely mobile in a cage to control any stress caused by immobilization in the exposure module. Brains were perfusion-fixed with 4% paraformaldehyde and three coronal levels immunostained for glial fibrillary acidic protein (GFAP). These brain slices were then examined by light microscopy and the amount of this immunomarker quantified using a color deconvolution method. There was no change in astrocytic GFAP immunostaining in brains after long-term exposure to mobile telephony microwaves compared to control (sham-exposed or freely moving caged mice). It was concluded that long-term (2 years) exposure of murine brains to mobile telephone RF fields did not produce any astrocytic reaction (astrogliosis) detectable by GFAP immunostaining. © 2015 Wiley Periodicals, Inc.

Experimental analysis of the effects of consumer exclusion on recruitment and succession of a coral reef system along a water quality gradient in the Spermonde Archipelago, Indonesia

NASA Astrophysics Data System (ADS)

Plass-Johnson, Jeremiah G.; Heiden, Jasmin P.; Abu, Nur; Lukman, Muhammad; Teichberg, Mirta

2016-03-01

The composition of coral reef benthic communities is strongly affected by variation in water quality and consumer abundance and composition. This is particularly evident in highly populated coastal regions where humans depend on coral reef resources and where terrestrial run-off can change the chemical composition of the water. We tested the effects of grazing pressure and ambient water conditions along an established eutrophication gradient on the recruitment and successional development of benthic communities of the Spermonde Archipelago, Indonesia, through caging experiments with settlement tiles. Within 1 month, benthic community composition of the closest reef to land, near the city of Makassar, was significantly different from other sites further offshore, driven primarily by differences in recruitment of invertebrates or turf algae. In contrast to other caging experiments, consumer exclusion had no effect after 3 months, suggesting that larger, mobile consumers had little effect on the benthic communities of these reefs at all sites. Despite conditions that usually favour macroalgal development, this group was rarely observed on recruitment tiles even after 4 months of consumer exclusion. Furthermore, tiles from both the caged and open treatments retained high proportions of open space indicating the possible role of small-sized or non-fish consumers that were not excluded from the experiment. These results indicate that, unlike many other studies, benthic consumers in the Spermonde Archipelago had little effect on the recruitment and early succession of the reef habitat and that unexamined biota such as mesograzers may be significant in degraded systems.

A sorting system with automated gates permits individual operant experiments with mice from a social home cage.

PubMed

Winter, York; Schaefers, Andrea T U

2011-03-30

Behavioral experiments based on operant procedures can be time-consuming for small amounts of data. While individual testing and handling of animals can influence attention, emotion, and behavior, and interfere with experimental outcome, many operant protocols require individual testing. We developed an RFID-technology- and transponder-based sorting system that allows removing the human factor for longer-term experiments. Identity detectors and automated gates route mice individually from their social home cage to an adjacent operant compartment with 24/7 operation. CD1-mice learnt quickly to individually pass through the sorting system. At no time did more than a single mouse enter the operant compartment. After 3 days of adjusting to the sorting system, groups of 4 mice completed about 50 experimental trials per day in the operant compartment without experimenter intervention. The automated sorting system eliminates handling, isolation, and disturbance of the animals, eliminates experimenter-induced variability, saves experimenter time, and is financially economical. It makes possible a new approach for high-throughput experimentation, and is a viable tool for increasing quality and efficiency of many behavioral and neurobiological investigations. It can connect a social home cage, through individual sorting automation, to diverse setups including classical operant chambers, mazes, or arenas with video-based behavior classification. Such highly automated systems will permit efficient high-throughput screening even for transgenic animals with only subtle neurological or psychiatric symptoms where elaborate or longer-term protocols are required for behavioral diagnosis. Copyright © 2011 Elsevier B.V. All rights reserved.

Comparison of Expandable and Fixed Interbody Cages in a Human Cadaver Corpectomy Model: Fatigue Characteristics.

PubMed

Pekmezci, Murat; Tang, Jessica A; Cheng, Liu; Modak, Ashin; McClellan, Robert T; Buckley, Jenni M; Ames, Christopher P

2016-11-01

In vitro cadaver biomechanics study. The goal of this study is to compare the in situ fatigue life of expandable versus fixed interbody cage designs. Expandable cages are becoming more popular, in large part, due to their versatility; however, subsidence and catastrophic failure remain a concern. This in vitro analysis investigates the fatigue life of expandable and fixed interbody cages in a single level human cadaver corpectomy model by evaluating modes of subsidence of expandable and fixed cages as well as change in stiffness of the constructs with cyclic loading. Nineteen specimens from 10 human thoracolumbar spines (T10-L2, L3-L5) were biomechanically evaluated after a single level corpectomy that was reconstructed with an expandable or fixed cage and anterior dual rod instrumentation. All specimens underwent 98 K cycles to simulate 3 months of postoperative weight bearing. In addition, a third group with hyperlordotic cages was used to simulate catastrophic failure that is observed in clinical practice. Three fixed and 2 expandable cages withstood the cyclic loading despite perfect sagittal and coronal plane fitting of the endcaps. The majority of the constructs settled in after initial subsidence. The catastrophic failures that were observed in clinical practice could not be reproduced with hyperlordotic cages. However, all cages in this group subsided, and 60% resulted in endplate fractures during deployment of the cage. Despite greater surface contact area, expandable cages have a trend for higher subsidence rates when compared with fixed cages. When there is edge loading as in the hyperlordotic cage scenario, there is a higher risk of subsidence and intraoperative fracture during deployment of expandable cages.

In vitro and in vivo acaricidal activity and residual toxicity of spinosad to the poultry red mite, Dermanyssus gallinae.

PubMed

George, D R; Shiel, R S; Appleby, W G C; Knox, A; Guy, J H

2010-10-29

This paper describes two experiments conducted to examine the acaricidal potential of spinosad against the poultry red mite, Dermanyssus gallinae (De Geer), a serious ectoparasitic pest of laying hens. Spinosad is a natural product derived from the fermentation of the micro-organism Saccharopolyspora spinosa. In vitro testing confirmed that, when applied to a galvanised metal plate to the point of run-off, spinosad was toxic to adult female D. gallinae and suggested that at an application rate of 3.88 g/L a significant residual toxicity of spinosad could be achieved for up to 21 days. A subsequent in vivo experiment in a conventional cage housing system for laying hens demonstrated the acaricidal activity and residual toxicity to D. gallinae of a single application of spinosad when applied at either 1.94 or 3.88 g/L. Residual toxicity of spinosad at both of these application rates was maintained throughout the course of the 28 day post-spray study period, with a peak in product efficacy seen 14 days after spraying. The results suggest that the greater the D. gallinae population the greater will be the toxic effect of spinosad. Although the exact reasons for this are unclear, it can be speculated that conspecifics spread the product between each other more efficiently at higher mite population densities. However, further study is warranted to confirm this possibility. Application of spinosad in vivo had no effect on hen bodyweight or egg production parameters (number and weight), suggesting that this product could be used to effectively control D. gallinae infestations whilst birds are in lay. This paper also describes a novel method for effectively and efficiently achieving replication of treatments in a single poultry house, previously unpopulated with D. gallinae. Individual groups of conventional cages were stocked with hens, seeded with D. gallinae and used as replicates. Independence of replicates was achieved by isolating cage groups from one another using a non-drying glue barrier to minimise D. gallinae migration. Creating isolated populations (replicates) of D. gallinae within a single poultry house thus represents a novel and efficient means of screening other potential acaricides under field conditions. Copyright © 2010 Elsevier B.V. All rights reserved.

Design and modeling of Faraday cages for substrate noise isolation

NASA Astrophysics Data System (ADS)

Wu, Joyce H.; del Alamo, Jesús A.

2013-07-01

A Faraday cage structure using through-substrate vias is an effective strategy to suppress substrate crosstalk, particularly at high frequencies. Faraday cages can reduce substrate noise by 32 dB at 10 GHz, and 26 dB at 50 GHz. We have developed lumped-element, equivalent circuit models of the Faraday cages and test structures to better understand the performance of the Faraday cages. These models compare well to measured results and show that the vias of the Faraday cage act as an RLC shunt to ground that draws substrate current. Designing a Faraday cage to achieve optimum isolation requires low via impedance and mitigation of via sidewall capacitance. The Faraday cage inductance is correlated to the number of vias and via spacing of the cage and can be optimized for the frequency of operation.

Releases of Psyttalia fletcheri (Hymenoptera: Braconidae) and sterile flies to suppress melon fly (Diptera: Tephritidae) in Hawaii.

PubMed

Vargas, Roger I; Long, Jay; Miller, Neil W; Delate, Kathleen; Jackson, Charles G; Uchida, Grant K; Bautista, Renato C; Harris, Ernie J

2004-10-01

Ivy gourd, Coccinia grandis (L.) Voigt, patches throughout Kailua-Kona, Hawaii Island, HI, were identified as persistent sources of melon fly, Bactrocera cucurbitae (Coquillett). These patches had a low incidence of Psyttalia fletcheri (Silvestri), its major braconid parasitoid natural enemy in Hawaii, and were used to evaluate augmentative releases of P. fletcheri against melon fly. In field cage studies of releases, numbers of melon flies emerging from ivy gourd fruit placed inside treatment cages were reduced up to 21-fold, and numbers of parasitoids were increased 11-fold. In open field releases of P. fletcheri into ivy gourd patches, parasitization rates were increased 4.7 times in release plots compared with those in control plots. However, there was no significant reduction in emergence of melon flies from fruit. In subsequent cage tests with sterile melon flies and P. fletcheri, combinations of sterile flies and P. fletcheri produced the greatest reduction (9-fold) in melon fly emergence from zucchini, Cucurbita pepo L. Reductions obtained with sterile flies alone or in combination with parasitoids were significantly greater than those in the control, whereas those for parasitoids alone were not. Although these results suggest that the effects of sterile flies were greater than those for parasitoids, from a multitactic melon fly management strategy, sterile flies would complement the effects of P. fletcheri. Cost and sustainability of these nonchemical approaches will be examined further in an ongoing areawide pest management program for melon fly in Hawaii.

Ammonia and Carbon Dioxide Concentrations in Disposable and Reusable Ventilated Mouse Cages

PubMed Central

Silverman, Jerald; Bays, David W; Cooper, Sheldon F; Baker, Stephen P

2008-01-01

This study compares resuable and disposable individually ventilated mouse cages in terms of the formation of intracage CO2 and NH3. Crl:CD-1(ICR) female mice were placed in either disposable or reusable ventilated cages in a positive pressure animal rack. Intracage CO2 and NH3 were measured once daily for 9 d; temperature and relative humidity were monitored for the first 7 d. Results indicated higher CO2 levels in the rear of the disposable cages and in the front of the reusable cages. This pattern corresponded to where the mice tended to congregate. However, CO2 concentrations did not differ significantly between the 2 cage types. Average CO2 levels in both cage types never exceeded approximately 3000 ppm. Intracage NH3 began to rise in the reusable cages on day 4, reached approximately 50 ppm by day 5 and by day 9 was greater than 150 ppm at the cages' rear sampling port while remaining at approximately 70 ppm at the front sampling port. Intracage NH3 levels in the disposable cages remained less than or equal to 3.2 ppm. Intracage temperature and relative humidity were approximately the same in both cage types. We concluded that the disposable ventilated cage performed satisfactorily under the conditions of the study. PMID:18351723

One and two hydrogen molecules in the large cage of the structure II clathrate hydrate: quantum translation-rotation dynamics close to the cage wall.

PubMed

Sebastianelli, Francesco; Xu, Minzhong; Kanan, Dalal K; Bacić, Zlatko

2007-07-19

We have performed a rigorous theoretical study of the quantum translation-rotation (T-R) dynamics of one and two H2 and D2 molecules confined inside the large hexakaidecahedral (5(12)6(4)) cage of the sII clathrate hydrate. For a single encapsulated H2 and D2 molecule, accurate quantum five-dimensional calculations of the T-R energy levels and wave functions are performed that include explicitly, as fully coupled, all three translational and the two rotational degrees of freedom of the hydrogen molecule, while the cage is taken to be rigid. In addition, the ground-state properties, energetics, and spatial distribution of one and two p-H2 and o-D2 molecules in the large cage are calculated rigorously using the diffusion Monte Carlo method. These calculations reveal that the low-energy T-R dynamics of hydrogen molecules in the large cage are qualitatively different from that inside the small cage, studied by us recently. This is caused by the following: (i) The large cage has a cavity whose diameter is about twice that of the small cage for the hydrogen molecule. (ii) In the small cage, the potential energy surface (PES) for H2 is essentially flat in the central region, while in the large cage the PES has a prominent maximum at the cage center, whose height exceeds the T-R zero-point energy of H2/D2. As a result, the guest molecule is excluded from the central part of the large cage, its wave function localized around the off-center global minimum. Peculiar quantum dynamics of the hydrogen molecule squeezed between the central maximum and the cage wall manifests in the excited T-R states whose energies and wave functions differ greatly from those for the small cage. Moreover, they are sensitive to the variations in the hydrogen-bonding topology, which modulate the corrugation of the cage wall.

Sagittal Plane Correction Using the Lateral Transpsoas Approach: A Biomechanical Study on the Effect of Cage Angle and Surgical Technique on Segmental Lordosis.

PubMed

Melikian, Rojeh; Yoon, Sangwook Tim; Kim, Jin Young; Park, Kun Young; Yoon, Caroline; Hutton, William

2016-09-01

Cadaveric biomechanical study. To determine the degree of segmental correction that can be achieved through lateral transpsoas approach by varying cage angle and adding anterior longitudinal ligament (ALL) release and posterior element resection. Lordotic cage insertion through the lateral transpsoas approach is being used increasingly for restoration of sagittal alignment. However, the degree of correction achieved by varying cage angle and ALL release and posterior element resection is not well defined. Thirteen lumbar motion segments between L1 and L5 were dissected into single motion segments. Segmental angles and disk heights were measured under both 50 N and 500 N compressive loads under the following conditions: intact specimen, discectomy (collapsed disk simulation), insertion of parallel cage, 10° cage, 30° cage with ALL release, 30° cage with ALL release and spinous process (SP) resection, 30° cage with ALL release, SP resection, facetectomy, and compression with pedicle screws. Segmental lordosis was not increased by either parallel or 10° cages as compared with intact disks, and contributed small amounts of lordosis when compared with the collapsed disk condition. Placement of 30° cages with ALL release increased segmental lordosis by 10.5°. Adding SP resection increased lordosis to 12.4°. Facetectomy and compression with pedicle screws further increased lordosis to approximately 26°. No interventions resulted in a decrease in either anterior or posterior disk height. Insertion of a parallel or 10° cage has little effect on lordosis. A 30° cage insertion with ALL release resulted in a modest increase in lordosis (10.5°). The addition of SP resection and facetectomy was needed to obtain a larger amount of correction (26°). None of the cages, including the 30° lordotic cage, caused a decrease in posterior disk height suggesting hyperlordotic cages do not cause foraminal stenosis. N/A.

Scheduled Daily Mating Induces Circadian Anticipatory Activity Rhythms in the Male Rat

PubMed Central

Landry, Glenn J.; Opiol, Hanna; Marchant, Elliott G.; Pavlovski, Ilya; Mear, Rhiannon J.; Hamson, Dwayne K.; Mistlberger, Ralph E.

2012-01-01

Daily schedules of limited access to food, palatable high calorie snacks, water and salt can induce circadian rhythms of anticipatory locomotor activity in rats and mice. All of these stimuli are rewarding, but whether anticipation can be induced by neural correlates of reward independent of metabolic perturbations associated with manipulations of food and hydration is unclear. Three experiments were conducted to determine whether mating, a non-ingestive behavior that is potently rewarding, can induce circadian anticipatory activity rhythms in male rats provided scheduled daily access to steroid-primed estrous female rats. In Experiment 1, rats anticipated access to estrous females in the mid-light period, but also exhibited post-coital eating and running. In Experiment 2, post-coital eating and running were prevented and only a minority of rats exhibited anticipation. Rats allowed to see and smell estrous females showed no anticipation. In both experiments, all rats exhibited sustained behavioral arousal and multiple mounts and intromissions during every session, but ejaculated only every 2–3 days. In Experiment 3, the rats were given more time with individual females, late at night for 28 days, and then in the midday for 28 days. Ejaculation rates increased and anticipation was robust to night sessions and significant although weaker to day sessions. The anticipation rhythm persisted during 3 days of constant dark without mating. During anticipation of nocturnal mating, the rats exhibited a significant preference for a tube to the mating cage over a tube to a locked cage with mating cage litter. This apparent place preference was absent during anticipation of midday mating, which may reflect a daily rhythm of sexual reward. The results establish mating as a reward stimulus capable of inducing circadian rhythms of anticipatory behavior in the male rat, and reveal a critical role for ejaculation, a modulatory role for time of day, and a potential confound role for uncontrolled food intake. PMID:22848408

EVALUATION OF GENETIC DAMAGE IN FISH EXPOSED TO PESTICIDES IN FIELD AQUATIC MICROCOSMS

EPA Science Inventory

Single cell gel electrophoresis (SCG) and micronucleus (MN) assays were used to measure DNA strand breaks and chromosomal damage in fish blood erythrocytes as biological indicators of exposure to alachlor and atrazine in a surrogate aquatic ecosystem. Caged common carp (Cyprinus...

Effects of ipriflavone on caged layer bone metabolism in vitro and in vivo.

PubMed

Yao, J; Zhang, J; Hou, J-F

2007-03-01

The effects of ipriflavone on caged layer bone metabolism were examined in vitro and in vivo. Ipriflavone at 10(-8) M stimulated the activity of osteoblasts cultured from embryonic chick calvariae, and 10(-9) to 10(-7) M inhibited osteoclasts from chick tibias and humeri. Ipriflavone concentrations of 10(-4) and 10(-5) M inhibited osteoblast activity. These results suggest that ipriflavone influences bone metabolism by regulating the functional balance between osteoblasts and osteoclasts. Based on these in vitro experiments, in vivo studies were conducted to further clarify the effects of ipriflavone. Five hundred 58-wk-old ISA caged layers were divided into 5 groups that were fed diets containing 0, 15, 25, 50, and 100 ppm of ipriflavone. The experiment lasted 70 d. Egg production increased in hens fed 25 ppm and decreased in hens fed 50 and 100 ppm when compared with the controls and hens fed 15 ppm (P < 0.05). Egg weight, shell quality, BW, and serum P, Ca, estrogen, and bone mineral content were not affected by inclusion of ipriflavone in the diet. Hens consuming 25 ppm of ipriflavone had greater serum alkaline phosphatase and bone gla-protein levels than controls. Adding 25 ppm of ipriflavone to the feed appears to be close to an ideal level for clinical treatment of osteoporosis because of improved egg production while maintaining bone mineral content.

Semiochemical mediated enhancement of males to complement sterile insect technique in management of the tephritid pest Bactrocera tryoni (Froggatt).

PubMed

Khan, Mohammed Abul Monjur; Manoukis, Nicholas C; Osborne, Terry; Barchia, Idris M; Gurr, Geoff M; Reynolds, Olivia L

2017-10-17

Queensland fruit fly, Bactrocera tryoni (Froggatt), is the most significant pest of Australia's $9 billion horticulture industry. The sterile insect technique (SIT) and cue-lure (a synthetic analogue of raspberry ketone (RK))-based male annihilation technique (MAT) are two of the most effective management tools against this pest. However, combining these two approaches is considered incompatible as MAT kills sterile and 'wild' males indiscriminately. In the present study we tested the effect of pre-release feeding of B. tryoni on RK on their post-release survival and response to MAT in field cages and in a commercial orchard. In both settings, survival was higher for RK supplemented adults compared to control (i.e. RK denied) adults. A lower number of RK supplemented sterile males were recaptured in MAT baited traps in both the field cages and orchard trials compared to RK denied sterile males. The advantage of this novel "male replacement" approach (relatively selective mortality of wild males at lure-baited traps while simultaneously releasing sterile males) is increasing the ratio of sterile to wild males in the field population, with potential for reducing the number of sterile males to be released.

Iron oxide nanoparticles in NaA zeolite cages

NASA Astrophysics Data System (ADS)

Kulshreshtha, S. K.; Vijayalakshmi, R.; Sudarsan, V.; Salunke, H. G.; Bhargava, S. C.

2013-07-01

Zeolite NaA samples with varying concentration of Fe3+ ions have been prepared by wet chemical method. Based on powder X-ray diffraction, 29Si and 27Al MAS NMR and Fe3+ EPR investigations, the formation of nano-sized ferric oxide particles inside the larger α-cages of zeolite NaA has been established. Both Mössbauer effect and magnetization measurements carried out down to 4.5 K established the superparamagnetic behaviour of these Fe2O3 particles with a blocking temperature of ≈20 K, where the magnetization values showed deviation for the zero field cooled and field cooled samples and the appearance of a very narrow magnetic hysteresis loop below this temperature. For all Fe3+ containing samples the room temperature Mössbauer spectrum is a broad quadrupole doublet with chemical shift, δ ≈ 0.33 mm/s and quadrupole splitting, ΔEq ≈ 0.68 mm/s. Variable temperature 57Fe Mössbauer effect measurements exhibited magnetic features below the blocking temperature and at 4.5 K, the observed spectrum is a broad magnetic sextet characterized by an internal hyperfine field value of ≈504 kOe along with a very weak central superparamagnetic quadrupole doublet.

Impact of Entomophaga maimaiga (Entomophthorales: Entomophthoraceae) on outbreak gypsy moth populations (Lepidoptera: Erebidae): the role of weather.

PubMed

Reilly, James R; Hajek, Ann E; Liebhold, Andrew M; Plymale, Ruth

2014-06-01

The fungal pathogen Entomophaga maimaiga Humber, Shimazu, and Soper is prevalent in gypsy moth [Lymantria dispar (L.)] populations throughout North America. To understand how weather-related variables influence gypsy moth-E. maimaiga interactions in the field, we measured fungal infection rates at 12 sites in central Pennsylvania over 3 yr, concurrently measuring rainfall, soil moisture, humidity, and temperature. Fungal mortality was assessed using both field-collected larvae and laboratory-reared larvae caged on the forest floor. We found significant positive effects of moisture-related variables (rainfall, soil moisture, and relative humidity) on mortality due to fungal infection in both data sets, and significant negative effects of temperature on the mortality of field-collected larvae. Lack of a clear temperature relationship with the mortality of caged larvae may be attributable to differential initiation of infection by resting spores and conidia or to microclimate effects. These relationships may be helpful in understanding how gypsy moth dynamics vary across space and time, and in forecasting how the gypsy moth and fungus will interact as they move into warmer or drier areas, or new weather conditions occur due to climate change.

Anomalous effects of radioactive decay rates and capacitance values measured inside a modified Faraday cage: Correlations with space weather

NASA Astrophysics Data System (ADS)

Scholkmann, F.; Milián-Sánchez, V.; Mocholí-Salcedo, A.; Milián, C.; Kolombet, V. A.; Verdú, G.

2017-03-01

Recently we reported (Milián-Sánchez V. et al., Nucl. Instrum. Methods A, 828 (2016) 210) our experimental results involving 226Ra decay rate and capacitance measurements inside a modified Faraday cage. Our measurements exhibited anomalous effects of unknown origin. In this letter we report new results regarding our investigation into the origins of the observed effects. We report preliminary findings of a correlation analysis between the radioactive decay rates and capacitance time series and space weather related variables (geomagnetic field disturbances and cosmic-ray neutron counts). A significant correlation was observed for specific data sets. The results are presented and possible implications for future work discussed.

Nasal Histopathology and Intracage Ammonia Levels in Female Groups and Breeding Mice Housed in Static Isolation Cages

PubMed Central

Mexas, Angela M; Brice, Angela K; Caro, Adam C; Hillanbrand, Troy S

2015-01-01

Many factors influence ammonia levels in rodent cages, and high intracage ammonia has been associated with specific types of abnormal nasal pathology in mice. The use of autoclaved corncob bedding and the maintenance of low room humidity reduce the accumulation of ammonia in mouse cages. However, there are no engineering standards that define the limits of ammonia exposure for mice housed in static isolation cages. Regulatory guidance indicates that solid bottom cages must be sanitized at least weekly and that cage components in direct contact with animals must be sanitized at least every 2 wk. Common practice is to replace the bottoms and bedding of static isolation cages once weekly. To determine whether changing static isolation cages once weekly is an appropriate performance standard for mice, we prospectively evaluated the relationship between ammonia levels, nasal histopathology, and housing densities in various grouping strategies of mice housed in static isolation cages. Here, we report that the average nasal pathology score per cage and intracage ammonia levels were correlated, but nasal pathology scores did not differ among mice housed in breeding pairs, breeding trios, or female groups. In light of ammonia levels and histopathology scores as performance standards, these results suggest that a weekly cage-change frequency for static isolation cages does not result in adverse effects. Our results provide evidence to support current practices in the use of static isolation cages for housing laboratory mice in modern vivaria. PMID:26424245

Disparities in Ammonia, Temperature, Humidity, and Airborne Particulate Matter between the Micro-and Macroenvironments of Mice in Individually Ventilated Caging

PubMed Central

Rosenbaum, Matthew D; VandeWoude, Susan; Volckens, John; Johnson, Thomas E

2010-01-01

Animal room environmental parameters typically are monitored with the assumption that the environment within the cage closely mirrors the room environment. This study evaluated that premise by examining macro- (room) and microenvironmental (cage) parameters in individually ventilated cages housing mice with variable amounts of bedding over a period of 17 d without cage changes. Intracage ammonia levels remained within recommended human guidelines but were higher than room levels, confirming that microisolation caging is efficient at preventing ammonia generated from animal waste from escaping into the room. Humidity and temperature within cages were consistently higher than room levels. Particles in the room predominantly consisted of fine particles (diameter less than 2.5 µm), presumably from the ambient atmosphere; some of these particles were found in the cage microenvironment. In addition, mouse activity within cages produced larger particles, and these particles contributed to substantially higher aerosol mass concentrations within the cage. These findings demonstrate that, although cage and room environmental parameters differ, knowledge of room environmental conditions can be used to predict certain conditions within the cage. This association is relevant in that typical animal care standard operating procedures rely on room measurements, not intracage measurements, which arguably are more important for assessing animal welfare. Further, location and ambient climate can influence particle concentrations in the room, and consequently within the animal cage, suggesting local weather patterns and air quality may account for variability among studies conducted at sites that are geographically divergent. PMID:20353692

Elimination of Subsidence with 26-mm-Wide Cages in Extreme Lateral Interbody Fusion.

PubMed

Lang, Gernot; Navarro-Ramirez, Rodrigo; Gandevia, Lena; Hussain, Ibrahim; Nakhla, Jonathan; Zubkov, Micaella; Härtl, Roger

2017-08-01

Extreme lateral interbody fusion (ELIF) has gained popularity as a minimally invasive technique for indirect decompression. However, graft subsidence potentially threatens long-term success of ELIF. This study evaluated whether 26-mm-wide cages can eliminate subsidence and subsequent loss of decompression in ELIF. Patients undergoing ELIF surgery using a 26-mm-wide cage were analyzed retrospectively. Patient demographics and perioperative data for radiographic and clinical outcomes were recorded. Radiographic parameters included regional sagittal lumbar lordosis and foraminal and disc height. Clinical parameters were evaluated using the Oswestry Disability Index and visual analog scale. Subsidence of 26-mm-wide cages was compared with previous outcomes of patients undergoing ELIF using 18-mm-wide and 22-mm-wide cages. There were 21 patients and 28 spinal segments analyzed. Radiographic outcome measures such as disc and foraminal height revealed significant improvement at follow-up compared with before surgery (P = 0.001). Postoperative to last follow-up cage subsidence translated into 0.34 mm ± 0.26 and -0.55 mm ± 0.64 in disc and foraminal height loss, respectively. Patients with 26-mm-wide cages experienced less subsidence by means of disc (26 mm vs. 18 mm and 22 mm, P ≤ 0.05) and foraminal height (26 mm vs. 18 mm, P = 0.005; 26 mm vs. 22 mm, P = 0.208) loss compared with patients receiving 18-mm-wide and 22-mm-wide cages. The 26-mm-wide cages almost eliminated cage subsidence in ELIF. Compared with 18-mm-wide and 22-mm-wide cages, 26-mm-wide cages significantly reduced cage subsidence in ELIF at midterm follow-up. A 26-mm-wide cage should be used in ELIF to achieve sustained indirect decompression. Copyright © 2017. Published by Elsevier Inc.

Do Lordotic Cages Provide Better Segmental Lordosis Versus Nonlordotic Cages in Lateral Lumbar Interbody Fusion (LLIF)?

PubMed

Sembrano, Jonathan N; Horazdovsky, Ryan D; Sharma, Amit K; Yson, Sharon C; Santos, Edward R G; Polly, David W

2017-05-01

A retrospective comparative radiographic review. To evaluate the radiographic changes brought about by lordotic and nonlordotic cages on segmental and regional lumbar sagittal alignment and disk height in lateral lumbar interbody fusion (LLIF). The effects of cage design on operative level segmental lordosis in posterior interbody fusion procedures have been reported. However, there are no studies comparing the effect of sagittal implant geometry in LLIF. This is a comparative radiographic analysis of consecutive LLIF procedures performed with use of lordotic and nonlordotic interbody cages. Forty patients (61 levels) underwent LLIF. Average age was 57 years (range, 30-83 y). Ten-degree lordotic PEEK cages were used at 31 lumbar interbody levels, and nonlordotic cages were used at 30 levels. The following parameters were measured on preoperative and postoperative radiographs: segmental lordosis; anterior and posterior disk heights at operative level; segmental lordosis at supra-level and subjacent level; and overall lumbar (L1-S1) lordosis. Measurement changes for each cage group were compared using paired t test analysis. The use of lordotic cages in LLIF resulted in a significant increase in lordosis at operative levels (2.8 degrees; P=0.01), whereas nonlordotic cages did not (0.6 degrees; P=0.71) when compared with preoperative segmental lordosis. Anterior and posterior disk heights were significantly increased in both groups (P<0.01). Neither cage group showed significant change in overall lumbar lordosis (lordotic P=0.86 vs. nonlordotic P=0.25). Lordotic cages provided significant increase in operative level segmental lordosis compared with nonlordotic cages although overall lumbar lordosis remained unchanged. Anterior and posterior disk heights were significantly increased by both cages, providing basis for indirect spinal decompression.

Development of furnished cages for laying hens.

PubMed

Appleby, M C; Walker, A W; Nicol, C J; Lindberg, A C; Freire, R; Hughes, B O; Elson, H A

2002-09-01

1. A 3-year trial was carried out of cages for laying hens, occupying a full laying house. The main cage designs used were 5000 cm2 in area, 50 cm high at the rear and furnished with nests and perches. F cages had a front rollaway nest at the side, lined with artificial turf. FD cages also had a dust bath containing sand over the nest. H cages had two nest hollows at the side, one in front of the other. They were compared with conventional cages 2500 cm2 in area and 38 cm high at the rear. 2. Cages were stocked with from 4 to 8 ISA Brown hens per cage, resulting in varied allowances of area, feeder and perch per bird. No birds were beak trimmed. In F and FD cages two further treatments were applied: nests and dust baths were sometimes fitted with gates to exclude birds from dust baths in the morning and from both at night; elevated food troughs, with a lip 33 cm above the cage floor, were compared with standard troughs. 3. Management of the house was generally highly successful, with temperature control achieved by ventilation. Egg production was above breeders' standards and not significantly affected by cage design. More eggs per bird were collected when there were fewer birds per cage but food consumption also then tended to be higher. 4. The number of downgraded eggs was variable, with some tendency for more in furnished cages. Eggs laid in dust baths were often downgraded. Those laid at the back of the cage were frequently dirty because of accumulation of droppings. H nests were unsuccessful, with less than 50% of eggs laid in the nest hollows. However, up to 93% of eggs were laid in front rollaways, and few of these were downgraded. 5. Feather and foot damage were generally less in furnished than in conventional cages, greater where there were more birds per cage. With an elevated food trough there was less feather damage but more overgrowth of claws. In year 2, mortality was greater in cages with more birds. 6. Pre-laying behaviour was mostly settled in front rollaway nests. Dust baths were used more for pecking and scratching than for dust bathing. Comfort behaviour was more frequent in furnished cages than conventional, although still not frequent. Locomotion was strongly affected by number of birds per cage or by space per bird, being reduced by crowding. Most birds perched at night except in one treatment providing only 10.7 cm perch per bird. 7. Behaviour was more unrestricted and varied, and physical condition was better, in furnished than in conventional cages. However, egg production will cost more in furnished cages, partly because more eggs are downgraded. Dust baths must be fitted with gates that the birds cannot open from outside, but gates for nest boxes were found unnecessary. If a low perch is fitted it must be far enough from the back of the cage for birds to walk there. 8. Where there was less space per bird (more birds per cage) than the requirements in the 1999 European Commission Directive on laying hens, there were: fewer eggs per hen, but still above the breeders' target; lower food consumption; more feather and foot damage, but less than in conventional cages; higher mortality in one trial out of three; less freedom of movement. However, the results were still very good even with 8 birds per cage, and support the principle that furnished cages provide an acceptable way of protecting the welfare of laying hens.

Replica exchange simulation of reversible folding/unfolding of the Trp-cage miniprotein in explicit solvent: on the structure and possible role of internal water.

PubMed

Paschek, Dietmar; Nymeyer, Hugh; García, Angel E

2007-03-01

We simulate the folding/unfolding equilibrium of the 20-residue miniprotein Trp-cage. We use replica exchange molecular dynamics simulations of the AMBER94 atomic detail model of the protein explicitly solvated by water, starting from a completely unfolded configuration. We employ a total of 40 replicas, covering the temperature range between 280 and 538 K. Individual simulation lengths of 100 ns sum up to a total simulation time of about 4 micros. Without any bias, we observe the folding of the protein into the native state with an unfolding-transition temperature of about 440 K. The native state is characterized by a distribution of root mean square distances (RMSD) from the NMR data that peaks at 1.8A, and is as low as 0.4A. We show that equilibration times of about 40 ns are required to yield convergence. A folded configuration in the entire extended ensemble is found to have a lifetime of about 31 ns. In a clamp-like motion, the Trp-cage opens up during thermal denaturation. In line with fluorescence quenching experiments, the Trp-residue sidechain gets hydrated when the protein opens up, roughly doubling the number of water molecules in the first solvation shell. We find the helical propensity of the helical domain of Trp-cage rather well preserved even at very high temperatures. In the folded state, we can identify states with one and two buried internal water molecules interconnecting parts of the Trp-cage molecule by hydrogen bonds. The loss of hydrogen bonds of these buried water molecules in the folded state with increasing temperature is likely to destabilize the folded state at elevated temperatures.

SCORHE: A novel and practical approach to video monitoring of laboratory mice housed in vivarium cage racks

PubMed Central

Dennis, John U.; Krynitsky, Jonathan; Garmendia-Cedillos, Marcial; Swaroop, Kanchan; Malley, James D.; Pajevic, Sinisa; Abuhatzira, Liron; Bustin, Michael; Gillet, Jean-Pierre; Gottesman, Michael M.; Mitchell, James B.; Pohida, Thomas J.

2015-01-01

The System for Continuous Observation of Rodents in Home-cage Environment (SCORHE) was developed to demonstrate the viability of compact and scalable designs for quantifying activity levels and behavior patterns for mice housed within a commercial ventilated cage rack. The SCORHE in-rack design provides day- and night-time monitoring with the consistency and convenience of the home-cage environment. The dual-video camera custom hardware design makes efficient use of space, does not require home-cage modification, and is animal-facility user-friendly. Given the system’s low cost and suitability for use in existing vivariums without modification to the animal husbandry procedures or housing setup, SCORHE opens up the potential for the wider use of automated video monitoring in animal facilities. SCORHE’s potential uses include day-to-day health monitoring, as well as advanced behavioral screening and ethology experiments, ranging from the assessment of the short- and long-term effects of experimental cancer treatments to the evaluation of mouse models. When used for phenotyping and animal model studies, SCORHE aims to eliminate the concerns often associated with many mouse-monitoring methods, such as circadian rhythm disruption, acclimation periods, lack of night-time measurements, and short monitoring periods. Custom software integrates two video streams to extract several mouse activity and behavior measures. Studies comparing the activity levels of ABCB5 knockout and HMGN1 overexpresser mice with their respective C57BL parental strains demonstrate SCORHE’s efficacy in characterizing the activity profiles for singly- and doubly-housed mice. Another study was conducted to demonstrate the ability of SCORHE to detect a change in activity resulting from administering a sedative. PMID:24706080

SCORHE: a novel and practical approach to video monitoring of laboratory mice housed in vivarium cage racks.

PubMed

Salem, Ghadi H; Dennis, John U; Krynitsky, Jonathan; Garmendia-Cedillos, Marcial; Swaroop, Kanchan; Malley, James D; Pajevic, Sinisa; Abuhatzira, Liron; Bustin, Michael; Gillet, Jean-Pierre; Gottesman, Michael M; Mitchell, James B; Pohida, Thomas J

2015-03-01

The System for Continuous Observation of Rodents in Home-cage Environment (SCORHE) was developed to demonstrate the viability of compact and scalable designs for quantifying activity levels and behavior patterns for mice housed within a commercial ventilated cage rack. The SCORHE in-rack design provides day- and night-time monitoring with the consistency and convenience of the home-cage environment. The dual-video camera custom hardware design makes efficient use of space, does not require home-cage modification, and is animal-facility user-friendly. Given the system's low cost and suitability for use in existing vivariums without modification to the animal husbandry procedures or housing setup, SCORHE opens up the potential for the wider use of automated video monitoring in animal facilities. SCORHE's potential uses include day-to-day health monitoring, as well as advanced behavioral screening and ethology experiments, ranging from the assessment of the short- and long-term effects of experimental cancer treatments to the evaluation of mouse models. When used for phenotyping and animal model studies, SCORHE aims to eliminate the concerns often associated with many mouse-monitoring methods, such as circadian rhythm disruption, acclimation periods, lack of night-time measurements, and short monitoring periods. Custom software integrates two video streams to extract several mouse activity and behavior measures. Studies comparing the activity levels of ABCB5 knockout and HMGN1 overexpresser mice with their respective C57BL parental strains demonstrate SCORHE's efficacy in characterizing the activity profiles for singly- and doubly-housed mice. Another study was conducted to demonstrate the ability of SCORHE to detect a change in activity resulting from administering a sedative.

Temporal Effects on the Incidence and Severity of Brown Marmorated Stink Bug (Hemiptera: Pentatomidae) Feeding Injury to Peaches and Apples during the Fruiting Period in Virginia.

PubMed

Joseph, Shimat V; Nita, Mizuho; Leskey, Tracy C; Bergh, J Christopher

2015-04-01

Exclusion cages were used to compare the incidence and severity of feeding injury from brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), on 'Redhaven' peaches, 'Golden Delicious' apples, and 'Smoothee Golden' apples at harvest, following sequential periods of exposure to natural H. halys populations during the 2011 and 2012 growing seasons in Virginia. The fruit used in these experiments were in orchards or on trees that were not managed for H. halys. Treatments were sets of 50 fruit that were always caged, never caged, or exposed during one interval during the fruiting period of peaches and apples in the Mid-Atlantic region of the United States. The cages effectively prevented feeding injury from H. halys. Peaches and apples that were never caged showed the highest percentages of injured fruit at harvest. Exposure treatment had a significant effect on the percentage of fruit showing external injury at harvest in both years for apples and in 2012 for peaches, and a significant effect on the percentage of apples and peaches showing internal injury at harvest in both years. There was no consistent effect of each exposure period on peach injury, but apples exposed during the mid- to latter portion of the season tended to show most injury. Across all exposure periods, more internal than external injuries were recorded at harvest from peaches, while apples tended to have equal or very similar numbers of both kinds of injury. The implications of these results to H. halys management in eastern apple orchards are discussed. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Effects of the tricothecene mycotoxin diacetoxyscirpenol on egg production of broiler breeders.

PubMed

Brake, J; Hamilton, P B; Kittrell, R S

2002-12-01

Three experiments were conducted to determine the effects of 4,15-diacetoxyscirpenol (DAS) on egg quality and egg production of broiler breeders. In Experiment 1, feed containing 0, 1.25, 2.5, or 5.0 mg DAS/ kg was fed from 67 to 69 wk of age followed by a 3-wk recovery period on a slat-litter floor. In Experiment 2, individually caged broiler breeder females were studied from 23 to 31 wk of age. The basal diet containing 0, 5, 10, or 20 mg DAS/kg was fed from 25 to 27 wk of age. In Experiment 3, individually caged broiler breeder hens were studied from 23 to 32 wk of age. DAS was fed at levels of 0 (basal), 5, 10, and 20 mg DAS/kg for 2 wk beginning at Week 24, followed by the basal breeder diet for 7 wk. Egg production was not affected by levels of up to 5 mg DAS/kg in the older hens of Experiment 1. When fed from 25 to 27 wk of age in Experiment 2, DAS decreased egg production at the 20 mg/kg level only. When fed from 24 to 25 wk of age in Experiment 3, DAS had no significant effect on egg production or egg quality. Short-term consumption of DAS at levels that might naturally occur appears to have little effect on broiler breeder egg production.

Acclimatization of mice to different cage types and social groupings with respect to fecal secretion of IgA and corticosterone metabolites.

PubMed

Bundgaard, Cathrine Juel; Kalliokoski, Otto; Abelson, Klas S P; Hau, Jann

2012-01-01

Stress associated with transport and change of environment may have widespread effects on physiological parameters in laboratory animals. To investigate the time needed for mice to acclimatize to a new environment, based on fecal IgA and corticosterone excretion, eightweek-old BALB/c mice of both genders were housed either in groups of eight in different cage types in open conventional cages, in Individual Ventilated Cages (IVC), in open conventional cages inside a plastic isolator, or in different group sizes (8, 4, 8, 10 or 12 mice in each group) in open conventional cages. Feces were collected from each cage on routine cage changing. There was no significant difference in corticosterone excretion in feces between animals housed in the different cage types or between animals housed in different group sizes. IgA excretion for both males and females was found to be affected by transfer of mice into a novel cage, and it was found that it takes at least four weeks for the mice to acclimatize to a new environment with respect to this parameter.

Effectiveness of insecticide-treated and non-treated trap plants for the management of Frankliniella occidentalis (Thysanoptera: Thripidae) in greenhouse ornamentals.

PubMed

Buitenhuis, Rosemarije; Shipp, J Les; Jandricic, Sarah; Murphy, Graeme; Short, Mike

2007-09-01

The effectiveness of trap cropping as an integrated control strategy against western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), was explored in potted chrysanthemum, Dendranthema grandiflora (Tzvelev), greenhouse crops. The efficacy of flowering chrysanthemum trap plants, either treated with the insecticide spinosad or untreated, to regulate F. occidentalis populations was tested at different spatial scales (small cage, large cage and commercial greenhouse) and for different time periods (1 or 4 weeks). It was demonstrated that flowering chrysanthemums as trap plants lower the number of adult F. occidentalis in a vegetative chrysanthemum crop and, as a result, reduce crop damage. In the 4 week large-cage trial and the commercial trial, significant differences between the control and the trap plant treatments started to appear in the third week of the experiment. Larvae were only significantly reduced by the presence of trap plants in the 1 week small-cage trials. There were no significant differences between treatments with spinosad-treated and untreated trap plants in the number of F. occidentalis on the crop. This suggests that there was minimal movement of adult F. occidentalis back and forth between the trap plants and the crop to feed and oviposit. It is concluded that the trap plant strategy is a useful tool for integrated pest management against F. occidentalis in greenhouses. 2007 Crown in the right of Canada

Dual stator winding variable speed asynchronous generator: optimal design and experiments

NASA Astrophysics Data System (ADS)

Tutelea, L. N.; Deaconu, S. I.; Popa, G. N.

2015-06-01

In the present paper is carried out a theoretical and experimental study of dual stator winding squirrel cage asynchronous generator (DSWA) behavior in the presence of saturation regime (non-sinusoidal) due to the variable speed operation. The main aims are the determination of the relations of calculating the equivalent parameters of the machine windings to optimal design using a Matlab code. Issue is limited to three phase range of double stator winding cage-induction generator of small sized powers, the most currently used in the small adjustable speed wind or hydro power plants. The tests were carried out using three-phase asynchronous generator having rated power of 6 [kVA].

Investigation of compressible vortex flow characteristics

NASA Technical Reports Server (NTRS)

Muirhead, V. U.

1977-01-01

The nature of intense air vortices was studied and the factors which determine the intensity and rate of decay of both single and pairs of vortices were investigated. Vortex parameters of axial pressure differential, circulation, outflow rates, separation distance and directions of rotation were varied. Unconfined vortices, generated by a single rotating cage, were intensified by an increasing axial pressure gradient. Breakdown occurred when the axial gradient became negligible. The core radius was a function of the axial gradient. Dual vortices, generated by two counterrotating cages, rotated opposite to the attached cages. With minimum spacing only one vortex was formed which rotated in a direction opposite to the attached cage. When one cage rotated at half the speed of the other cage, one vortex formed at the higher speed cage rotating in the cage direction.

Olfactory bulbectomy induces rapid and stable changes in basal and stress-induced locomotor activity, heart rate and body temperature responses in the home cage.

PubMed

Vinkers, C H; Breuer, M E; Westphal, K G C; Korte, S M; Oosting, R S; Olivier, B; Groenink, L

2009-03-03

Olfactory bulbectomy (OBX) in rats causes several behavioral and neurochemical changes. However, the extent and onset of physiological and behavioral changes induced after bulbectomy have been little examined. Male Sprague-Dawley rats received telemetric implants. Before and immediately after OBX surgery, basal and stress-induced heart rate, body temperature, and locomotor activity were measured in the home cage in sham (n=9) and OBX animals (n=11). Stress was induced using novel cage stress or witness stress. Bulbectomized animals differed physiologically and behaviorally from shams. Nocturnally, OBX animals were significantly more active compared with shams, had a higher core body temperature and displayed a decreased heart rate variability. During the light period, OBX animals had a significantly lower basal heart rate and a reduced heart rate variability. These effects became apparent 2-3 days after OBX surgery, and were stable over time. After witness stress, OBX animals showed smaller autonomic (body temperature and heart rate) responses compared with shams, but showed no difference in locomotor responses. In contrast, novel cage stress led to increased locomotor responses in OBX rats compared with sham rats, while no differences were found in autonomic responses. Removal of the olfactory bulbs results in rapid, stable and persistent changes in basal locomotor activity, body temperature, heart rate and heart rate variability. Although the sleep-wake cycle of these parameters is not altered, increases in circadian amplitude are apparent within 3 days after surgery. This indicates that physiological changes in the OBX rat are the immediate result of olfactory bulb removal. Further, stress responsivity in OBX rats depends on stressor intensity. Bulbectomized rats display smaller temperature and heart rate responses to less intense witness stress compared with sham rats. Increased locomotor responses to more intense novel cage stress are present in the home cage as well as the open field. The present study shows that olfactory bulbectomy has rapid and persistent influence on basal and stress-induced physiological parameters.

TU-H-BRA-01: The Physics of High Power Radiofrequency Isolation in a Novel Compact Linear Accelerator Based MRI Guided Radiation Therapy System

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

Lamb, J; Low, D; Mutic, S

Purpose: To develop a method for isolating the radiofrequency waves emanating from linear accelerator components from the magnetic resonance imaging (MRI) system of an integrated MRI-linac. Methods: An MRI-guided radiation therapy system has been designed that integrates a linear accelerator with simultaneous MR imaging. The radiofrequency waves created by the accelerating process would degrade MR image quality, so a method for containing the radiofrequency waves and isolating the MR imager from them was developed. The linear accelerator radiofrequency modulator was placed outside the room, so a filter was designed to eliminate the radiofrequency corresponding to the proton Larmour frequency ofmore » 14.7 MHz. Placing the radiofrequency emitting components in a typical Faraday cage would have reduced the radiofrequency emissions, but the design would be susceptible to small gaps in the shield due to the efficiency of the Faraday cage reflecting internal radiofrequency emissions. To reduce internal radiofrequency reflections, the Faraday cage was lined with carbon fiber sheets. Carbon fiber has the property of attenuating the radiofrequency energy so that the overall radiofrequency field inside the Faraday cage is reduced, decreasing any radiofrequency energy emitted from small gaps in the cage walls. Results: Within a 1.2 MHz band centered on the Larmor frequency, the radiofrequency (RF) leakage from the Faraday cage was measured to be −90 dB with no RF on, −40 dB with the RF on and no shield, returning to −90 dB with the RF on and shields in place. The radiofrequency filter attenuated the linear accelerator modulator emissions in the 14.7 MHz band by 70 dB. Conclusions: One of the major challenges in designing a compact linear accelerator based MRI-guided radiation therapy system, that of isolating the high power RF system from the MRI, has been solved. The measured radiofrequency emissions are sufficiently small to enable system integration. This research was funded by ViewRay, Inc., Oakwood, OH.« less

Animal Welfare and Food Safety Aspects of Confining Broiler Chickens to Cages

PubMed Central

Shields, Sara; Greger, Michael

2013-01-01

Simple Summary In commercial chicken meat production, broiler chickens are usually kept on the floor in ware-house like buildings, but the use of cages is becoming more common. Confining chickens to cages is a welfare problem, as has been thoroughly demonstrated for laying hens used for egg production. Caged broiler chickens may suffer from poor bone strength due to lack of exercise, feather loss, and restriction of natural behavior. There are also potential food safety concerns associated with the use of cages. While cages may provide an economic advantage in some geographical regions of the world, the severe, inherent disadvantages should also be considered before cages are more widely adopted in the global broiler chicken industry. Abstract In most areas of the world, broiler chickens are raised in floor systems, but cage confinement is becoming more common. The welfare of broiler chickens in cages is affected by movement restriction, poor bone strength due to lack of exercise, and prevention of key behavioral patterns such as dustbathing and ground scratching. Cages for broiler chickens also have a long history of causing skin and leg conditions that could further compromise welfare, but a lack of controlled studies makes it difficult to draw conclusions about newer cage designs. Cage environments are usually stocked at a higher density than open floor systems, and the limited studies available suggest that caging may lead to increased levels of fear and stress in the birds. Further, birds reared on the floor appear less likely to harbor and shed Salmonella, as litter may serve as a seeding agent for competitive exclusion by other microorganisms. Cages for laying hens used in egg production have met with substantial opposition due to welfare concerns and caging broiler chickens will likely be subject to the same kinds of social disapproval. PMID:26487409

Ammonia Levels and Urine-Spot Characteristics as Cage-Change Indicators for High-Density Individually Ventilated Mouse Cages

PubMed Central

Washington, Ida M; Payton, Mark E

2016-01-01

Mouse cage and bedding changes are potentially stressful to mice and are also labor- and resource-intensive. These changes are often performed on a calendar-based schedule to maintain a clean microenvironment and limit the concentrations of ammonia to which mice and workers are exposed. The current study sought to establish a performance-based approach to mouse cage-changing that uses urine spot characteristics as visual indicators of intracage ammonia levels. Colorimetric ammonia indicators were used to measure ammonia levels in individually-ventilated cages (IVC) housing male or female mice (n =5 per cage) of various strains at 1 to 16 d after cage change. Urine spot characteristics were correlated with ammonia levels to create a visual indicator of the cage-change criterion of 25 ppm ammonia. Results demonstrated a consistent increase in ammonia levels with days since cage change, with cages reaching the cage-change criterion at approximately 10 d for IVC containing male mice and 16 d for those with female mice. Ammonia levels were higher for male than female mice but were not correlated with mouse age. However, urine spot diameter, color, and edge characteristics were strongly correlated with ammonia levels. Husbandry practices based on using urine spot characteristics as indicators of ammonia levels led to fewer weekly cage changes and concomitant savings in labor and resources. Therefore, urine spot characteristics can be used as visual indicators of intracage ammonia levels for use of a performance (urine spot)-based approach to cage-changing frequency that maintains animal health and wellbeing. PMID:27177558

Natural selection on immune defense: A field experiment.

PubMed

Langeloh, Laura; Behrmann-Godel, Jasminca; Seppälä, Otto

2017-02-01

Predicting the evolution of phenotypic traits requires an understanding of natural selection on them. Despite its indispensability in the fight against parasites, selection on host immune defense has remained understudied. Theory predicts immune traits to be under stabilizing selection due to associated trade-offs with other fitness-related traits. Empirical studies, however, report mainly positive directional selection. This discrepancy could be caused by low phenotypic variation in the examined individuals and/or variation in host resource level that confounds trade-offs in empirical studies. In a field experiment where we maintained Lymnaea stagnalis snails individually in cages in a lake, we investigated phenotypic selection on two immune defense traits, phenoloxidase (PO)-like activity and antibacterial activity, in hemolymph. We used a diverse laboratory population and manipulated snail resource level by limiting their food supply. For six weeks, we followed immune activity, growth, and two fitness components, survival and fecundity of snails. We found that PO-like activity and growth were under stabilizing selection, while antibacterial activity was under positive directional selection. Selection on immune traits was mainly driven by variation in survival. The form of selection on immune defense apparently depends on the particular trait, possibly due to its importance for countering the present parasite community. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Efficacy of the organic-certified insecticide Diatect II against the boll weevil (Anthonomus grandis) in cotton.

PubMed

Sappington, Thomas W

2002-10-01

The efficacy of the organic insecticide Diatect II against boll weevil (Anthonomus grandis Boheman) in cotton (Gossypium hirsutum L) in the Lower Rio Grande Valley of Texas were assessed in small-plot field trials and greenhouse cage tests using azinphos-methyl treatments as a standard for comparison. Plastic sheets were placed in the furrows of the treated plots to retrieve boll weevils which dropped from the plants after being killed by the insecticides. Samples of live weevils taken by a tractor-mounted vacuum sampler revealed a modest, but significant, reduction in boll weevil populations in Diatect II plots. However, samples of dead weevils indicated that this reduction was due to movement of weevils out of the plots rather than to mortality. This interpretation is supported by greenhouse cage studies, where mortality in Diatect II treated cages was no greater than that in untreated control cages. The effects of insecticide treatments in small plots can be confounded easily and quickly by interplot movement of target insects. Although the relative effects of various compounds can usually be assessed by sampling the populations in plots soon after treatment, the best measure of efficacy is obtained by directly sampling insects that have died in the plot. This parameter is insulated from the effects of interplot movement, unless the toxicant is slow to immobilize the target insect. Taken together, our results indicate little efficacy by Diatect II against boll weevil under our test conditions.

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.

PubMed

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

2015-01-01

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 product of the proportional coverage of the ovipositing mosquito population with PPF contamination (CM) by the ovitrap-detectable rates of oviposition by wild mosquitoes into this subset of habitats [Formula: see text], divided by the titre of contaminated mosquitoes required to render them unproductive [Formula: see text], that approximately approach unity [Formula: see text]. The simple multiplicative relationship between CM and [Formula: see text], and the simple exponential decay effect they have upon uncontaminated aquatic habitats, allows application of this model by theoreticians and field biologists alike.

Studies on plasma profiles and its effect on dust charging in hydrogen plasma

NASA Astrophysics Data System (ADS)

Kakati, B.; Kausik, S. S.; Saikia, B. K.; Bandyopadhay, M.

2010-02-01

Plasma profiles and its influence on dust charging are studied in hydrogen plasma. The plasma is produced in a high vacuum device by a hot cathode discharge method and is confined by a cusped magnetic field cage. A cylindrical Espion advanced Langmuir probe having 0.15 mm diameter and 10.0 mm length is used to study the plasma parameters for various discharge conditions. Optimum operational discharge parameters in terms of charging of the dust grains are studied. The charge on the surface of the dust particle is calculated from the capacitance model and the current by the dust grains is measured by the combination of a Faraday cup and an electrometer. Unlike our previous experiments in which dust grains were produced in-situ, here a dust dropper is used to drop the dust particles into the plasma.

Compositions containing borane or carborane cage compounds and related applications

DOEpatents

Bowen, III, Daniel E; Eastwood, Eric A

2013-05-28

Compositions comprising a polymer-containing matrix and a filler comprising a cage compound selected from borane cage compounds, carborane cage compounds, metal complexes thereof, residues thereof, mixtures thereof, and/or agglomerations thereof, where the cage compound is not covalently bound to the matrix polymer. Methods of making and applications for using such compositions are also disclosed.

Compositions containing borane or carborane cage compounds and related applications

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

Bowen, III, Daniel E; Eastwood, Eric A

2014-11-11

Compositions comprising a polymer-containing matrix and a filler comprising a cage compound selected from borane cage compounds, carborane cage compounds, metal complexes thereof, residues thereof, mixtures thereof, and/or agglomerations thereof, where the cage compound is not covalently bound to the matrix polymer. Methods of making and applications for using such compositions are also disclosed.

Compositions containing borane or carborane cage compounds and related applications

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

Bowen, III, Daniel E.; Eastwood, Eric A.

2015-09-15

Compositions comprising a polymer-containing matrix and a filler comprising a cage compound selected from borane cage compounds, carborane cage compounds, metal complexes thereof, residues thereof, mixtures thereof, and/or agglomerations thereof, where the cage compound is not covalently bound to the matrix polymer. Methods of making and applications for using such compositions are also disclosed.

Tolerance of nonindigenous cichlid fishes (Cichlasoma urophthalmus, Hemichromis letourneuxi) to low temperature: laboratory and field experiments in south Florida

USGS Publications Warehouse

Schofield, Pamela J.; Loftus, William F.; Kobza, Robert M.; Cook, Mark I.; Slone, Daniel H.

2010-01-01

The cold tolerance of two non-native cichlids (Hemichromis letourneuxi and Cichlasoma urophthalmus) that are established in south Florida was tested in the field and laboratory. In the laboratory, fishes were acclimated to two temperatures (24 and 28°C), and three salinities (0, 10, and 35 ppt). Two endpoints were identified: loss of equilibrium (11.5–13.7°C for C. urophthalmus; 10.8–12.5°C for H. letourneuxi), and death (9.5–11.1°C for C. urophthalmus; 9.1–13.3°C for H. letourneuxi). In the field, fishes were caged in several aquatic habitats during two winter cold snaps. Temperatures were lowest (4.0°C) in the shallow marsh, where no fish survived, and warmest in canals and solution-holes. Canals and ditches as shallow as 50 cm provided thermal refuges for these tropical fishes. Because of the effect on survival of different habitat types, simple predictions of ultimate geographic expansion by non-native fishes using latitude and thermal isoclines are insufficient for freshwater fishes.

Development of an integrated CAD-FEA system for patient-specific design of spinal cages.

PubMed

Zhang, Mingzheng; Pu, Fang; Xu, Liqiang; Zhang, Linlin; Liang, Hang; Li, Deyu; Wang, Yu; Fan, Yubo

2017-03-01

Spinal cages are used to create a suitable mechanical environment for interbody fusion in cases of degenerative spinal instability. Due to individual variations in bone structures and pathological conditions, patient-specific cages can provide optimal biomechanical conditions for fusion, strengthening patient recovery. Finite element analysis (FEA) is a valuable tool in the biomechanical evaluation of patient-specific cage designs, but the time- and labor-intensive process of modeling limits its clinical application. In an effort to facilitate the design and analysis of patient-specific spinal cages, an integrated CAD-FEA system (CASCaDeS, comprehensive analytical spinal cage design system) was developed. This system produces a biomechanical-based patient-specific design of spinal cages and is capable of rapid implementation of finite element modeling. By comparison with commercial software, this system was validated and proven to be both accurate and efficient. CASCaDeS can be used to design patient-specific cages with a superior biomechanical performance to commercial spinal cages.

Computed Tomography Measurement of Rib Cage Morphometry in Emphysema

PubMed Central

Sverzellati, Nicola; Colombi, Davide; Randi, Giorgia; Pavarani, Antonio; Silva, Mario; Walsh, Simon L.; Pistolesi, Massimo; Alfieri, Veronica; Chetta, Alfredo; Vaccarezza, Mauro; Vitale, Marco; Pastorino, Ugo

2013-01-01

Background Factors determining the shape of the human rib cage are not completely understood. We aimed to quantify the contribution of anthropometric and COPD-related changes to rib cage variability in adult cigarette smokers. Methods Rib cage diameters and areas (calculated from the inner surface of the rib cage) in 816 smokers with or without COPD, were evaluated at three anatomical levels using computed tomography (CT). CTs were analyzed with software, which allows quantification of total emphysema (emphysema%). The relationship between rib cage measurements and anthropometric factors, lung function indices, and %emphysema were tested using linear regression models. Results A model that included gender, age, BMI, emphysema%, forced expiratory volume in one second (FEV1)%, and forced vital capacity (FVC)% fit best with the rib cage measurements (R2 = 64% for the rib cage area variation at the lower anatomical level). Gender had the biggest impact on rib cage diameter and area (105.3 cm2; 95% CI: 111.7 to 98.8 for male lower area). Emphysema% was responsible for an increase in size of upper and middle CT areas (up to 5.4 cm2; 95% CI: 3.0 to 7.8 for an emphysema increase of 5%). Lower rib cage areas decreased as FVC% decreased (5.1 cm2; 95% CI: 2.5 to 7.6 for 10 percentage points of FVC variation). Conclusions This study demonstrates that simple CT measurements can predict rib cage morphometric variability and also highlight relationships between rib cage morphometry and emphysema. PMID:23935872

Bee cups: Single-use cages for honey bee experiments

USDA-ARS?s Scientific Manuscript database

Honey bees face challenges ranging from poor nutrition to exposure to parasites, pathogens, and environmental chemicals. These challenges drain colony resources and have been tied to both subtle and extreme colony declines, including the enigmatic Colony Collapse Disorder (CCD). Understanding how ...

Influence of Tribology of Cage Material on Ball Bearing Cage Instability

NASA Astrophysics Data System (ADS)

Servais, S.; Duquenne, M.; Bozet, J.-L.

2013-09-01

By creating a solid lubricant thickness on both bearing races, a cage material of cryogenic ball bearing plays a significant role in the good dynamical behavior of the cage. This role is essential because of the lack of conventional lubricant into this kind of bearing.In this paper, a method able to identify if a particular potential cage material can correctly fulfill its function is described. In other words, if it can lead to a stable movement of the cage. From the identification of fundamental tribological parameters governing the cage behavior, this method presents an example of ranking of such materials. This is based on pin-on-disk tests and on a numerical approach.

Static air-gap eccentricity fault diagnosis using rotor slot harmonics in line neutral voltage of three-phase squirrel cage induction motor

NASA Astrophysics Data System (ADS)

Oumaamar, Mohamed El Kamel; Maouche, Yassine; Boucherma, Mohamed; Khezzar, Abdelmalek

2017-02-01

The mixed eccentricity fault detection in a squirrel cage induction motor has been thoroughly investigated. However, a few papers have been related to pure static eccentricity fault and the authors focused on the RSH harmonics presented in stator current. The main objective of this paper is to present an alternative method based on the analysis of line neutral voltage taking place between the supply and the stator neutrals in order to detect air-gap static eccentricity, and to highlight the classification of all RSH harmonics in line neutral voltage. The model of squirrel cage induction machine relies on the rotor geometry and winding layout. Such developed model is used to analyze the impact of the pure static air-gap eccentricity by predicting the related frequencies in the line neutral voltage spectrum. The results show that the line neutral voltage spectrum are more sensitive to the air-gap static eccentricity fault compared to stator current one. The theoretical analysis and simulated results are confirmed by experiments.

Automated Operant Conditioning in the Mouse Home Cage.

PubMed

Francis, Nikolas A; Kanold, Patrick O

2017-01-01

Recent advances in neuroimaging and genetics have made mice an advantageous animal model for studying the neurophysiology of sensation, cognition, and locomotion. A key benefit of mice is that they provide a large population of test subjects for behavioral screening. Reflex-based assays of hearing in mice, such as the widely used acoustic startle response, are less accurate than operant conditioning in measuring auditory processing. To date, however, there are few cost-effective options for scalable operant conditioning systems. Here, we describe a new system for automated operant conditioning, the Psibox. It is assembled from low cost parts, designed to fit within typical commercial wire-top cages, and allows large numbers of mice to train independently in their home cages on positive reinforcement tasks. We found that groups of mice trained together learned to accurately detect sounds within 2 weeks of training. In addition, individual mice isolated from groups also showed good task performance. The Psibox facilitates high-throughput testing of sensory, motor, and cognitive skills in mice, and provides a readily available animal population for studies ranging from experience-dependent neural plasticity to rodent models of mental disorders.

25 CFR 542.14 - What are the minimum internal control standards for the cage?

Code of Federal Regulations, 2010 CFR

2010-04-01

... the cage shall be recorded on a cage accountability form on a per-shift basis. (6) Only cash, cash... identity, including photo identification. (8) A file for customers shall be prepared prior to acceptance of... cage shall be summarized on a cage accountability form on a per shift basis and shall be supported by...

Atypical gnawing and cage destructive behavior in one strain of laboratory rat.

PubMed

Jacobs, H K; Van Pelt, L F; Dunlap, B K

1984-06-01

Approximately 80% of a colony of 900 Long Evans rats, Blu:(LE), gnawed on polypropylene shoe box type cages around the automatic watering grommet. The gnawing led to cage destruction and escape of the animals. The addition of a large stainless steel shield between the original grommet backing and the cage prevented further gnawing on the cage.

Effects of a 28-Day Cage-Change Interval on Intracage Ammonia Levels, Nasal Histology, and Perceived Welfare of CD1 Mice

PubMed Central

Vogelweid, Catherine M; Zapien, Kathleen A; Honigford, Matthew J; Li, Linghui; Li, Hua; Marshall, Heather

2011-01-01

We measured daily intracage ammonia levels and performed weekly assessments of CD1 male, female, and breeder mice housed within disposable, ventilated cages that remained unchanged for 28 d. We tested housing groups comprising 1, 3, or 5 sex-matched mice per cage and breeder pairs with litters. Mice housed in cages with higher concentrations of ammonia developed degeneration and inflammatory lesions in the nasal passages. Mean ammonia exposure levels that caused rhinitis were 181 ppm for 18 d. Ammonia exposures of 93 ppm for 16 d caused necrosis of the olfactory epithelium, whereas 52 ppm for 13 d caused epithelial degeneration. Observers could not detect visible signs of rhinitis or identify cages with elevated ammonia levels, nor did they identify any sick or distressed mice. Observers consistently assigned poorer welfare scores as cages became dirtier. We conclude that we can extend the cage-change interval to at least 28 d for disposable, ventilated caging housing a single CD1 mouse. Cages containing 3 CD1 mice of either sex should be changed biweekly, and cages containing 5 CD1 mice or breeder pairs should be changed at least once weekly. PMID:22330779

Dynamical cage behaviour and hydrogen migration in hydrogen and hydrogen-tetrahydrofuran clathrate hydrates

NASA Astrophysics Data System (ADS)

Gorman, Paul D.; English, Niall J.; MacElroy, J. M. D.

2012-01-01

Classical equilibrium molecular dynamics simulations have been performed to investigate dynamical properties of cage radial breathing modes and intra- and inter-cage hydrogen migration in both pure hydrogen and mixed hydrogen-tetrahydrofuran sII hydrates at 0.05 kbar and up to 250 K. For the mixed H2-THF system in which there is single H2 occupation of the small cage (labelled "1SC 1LC"), we find that no H2 migration occurs, and this is also the case for pure H2 hydrate with single small-cavity occupation and quadruple occupancy for large cages (dubbed "1SC 4LC"). However, for the more densely filled H2-THF and pure-H2 systems, in which there is double H2 occupation in the small cage (dubbed "2SC 1LC" and "2SC 4LC," respectively), there is an onset of inter-cage H2 migration events from the small cages to neighbouring cavities at around 200 K, with an approximate Arrhenius temperature-dependence for the migration rate from 200 to 250 K. It was found that these "cage hopping" events are facilitated by temporary openings of pentagonal small-cage faces with the relaxation and reformation of key stabilising hydrogen bonds during and following passage. The cages remain essentially intact up to 250 K, save for transient hydrogen bond weakening and reformation during and after inter-cage hydrogen diffusion events in the 200-250 K range. The "breathing modes," or underlying frequencies governing the variation in the cavities' radii, exhibit a certain overlap with THF rattling motion in the case of large cavities, while there is some overlap of small cages' radial breathing modes with lattice acoustic modes.

Algal growth and species composition under experimental control of herbivory, phosphorus and coral abundance in Glovers Reef, Belize.

PubMed

McClanahan, T R; Cokos, B A; Sala, E

2002-06-01

The proliferation of algae on disturbed coral reefs has often been attributed to (1) a loss of large-bodied herbivorous fishes, (2) increases in sea water nutrient concentrations, particularly phosphorus, and (3) a loss of hard coral cover or a combination of these and other factors. We performed replicated small-scale caging experiments in the offshore lagoon of Glovers Reef atoll, Belize where three treatments had closed-top (no large-bodied herbivores) and one treatment had open-top cages (grazing by large-bodied herbivores). Closed-top treatments simulated a reduced-herbivory situation, excluding large fishes but including small herbivorous fishes such as damselfishes and small parrotfishes. Treatments in the closed-top cages included the addition of high phosphorus fertilizer, live branches of Acropora cervicornis and a third unmanipulated control treatment. Colonization, algal biomass and species composition on dead A. palmata "plates" were studied weekly for 50 days in each of the four treatments. Fertilization doubled the concentration of phosphorus from 0.35 to 0.77 microM. Closed-top cages, particularly the fertilizer and A. cervicornis additions, attracted more small-bodied parrotfish and damselfish than the open-top cages such that there was moderate levels of herbivory in closed-top cages. The open-top cages did, however, have a higher abundance of the chemically and morphologically defended erect algal species including Caulerpa cupressoides, Laurencia obtusa, Dictyota menstrualis and Lobophora variegata. The most herbivore-resistant calcareous green algae (i.e. Halimeda) were, however, uncommon in all treatments. Algal biomass increased and fluctuated simultaneously in all treatments over time, but algal biomass, as measured by wet, dry and decalcified weight, did not differ greatly between the treatments with only marginally higher biomass (p < 0.06) in the fertilized compared to open-top cages. Algal species composition was influenced by all treatments with a maximum between-treatment Bray-Curtis similarity of only 29%. The fertilized cages showed rapid colonization by a mixed turf community largely composed of the filamentous brown (Hincksia mitchelliae) and green (Enteromorpha prolifera) species. Algal cover in the fertilized cages leveled at 80% after 20 days compared to less than 50% in the other treatments. There was no evidence that A. cervicornis suppressed algal colonization compared to the unmanipulated controls. Instead, the herbivore susceptible Padina sanctae-crucis was the most abundant algae followed by Jania capillacea in this treatment in contrast to the more chemically defended Dictyota menstrualis that dominated the unmanipulated controls. We conclude that A. cervicornis was not suppressing algae as a group and its loss cannot account for the observed changes in algal abundance in most reefs except for creating space. In contrast, A. cervicornis appears to attract aggressive damselfish that may reduce herbivory by larger herbivores. Phosphorus enrichment can lead to rapid colonization of space by filamentous turf communities but not high biomass and dominance of erect frondose algae within 50 days. Moderate levels of herbivory by large-bodied herbivores promoted moderately herbivore-resistant erect brown and green algae that are commonly reported on disturbed reefs. Consequently, all the studied factors influenced algal communities but seldom as commonly predicted.

Social transmission of Pavlovian fear: fear-conditioning by-proxy in related female rats.

PubMed

Jones, Carolyn E; Riha, Penny D; Gore, Andrea C; Monfils, Marie-H

2014-05-01

Pairing a previously neutral conditioned stimulus (CS; e.g., a tone) to an aversive unconditioned stimulus (US; e.g., a foot-shock) leads to associative learning such that the tone alone will elicit a conditioned response (e.g., freezing). Individuals can also acquire fear from a social context, such as through observing the fear expression of a conspecific. In the current study, we examined the influence of kinship/familiarity on social transmission of fear in female rats. Rats were housed in triads with either sisters or non-related females. One rat from each cage was fear conditioned to a tone CS+ shock US. On day two, the conditioned rat was returned to the chamber accompanied by one of her cage mates. Both rats were allowed to behave freely, while the tone was played in the absence of the foot-shock. The previously untrained rat is referred to as the fear-conditioned by-proxy (FCbP) animal, as she would freeze based on observations of her cage-mate's response rather than due to direct personal experience with the foot-shock. The third rat served as a cage-mate control. The third day, long-term memory tests to the CS were performed. Consistent with our previous application of this paradigm in male rats (Bruchey et al. in Behav Brain Res 214(1):80-84, 2010), our results revealed that social interactions between the fear conditioned and FCbP rats on day two contribute to freezing displayed by the FCbP rats on day three. In this experiment, prosocial behavior occurring at the termination of the cue on day two was significantly greater between sisters than their non-sister counterparts, and this behavior resulted in increased freezing on day three. Our results suggest that familiarity and/or kinship influences the social transmission of fear in female rats.

Social stimuli enhance phencyclidine (PCP) self-administration in rhesus monkeys

PubMed Central

Newman, Jennifer L.; Perry, Jennifer L.; Carroll, Marilyn E.

2007-01-01

Environmental factors, including social interaction, can alter the effects of drugs of abuse on behavior. The present study was conducted to examine the effects of social stimuli on oral phencyclidine (PCP) self-administration by rhesus monkeys. Ten adult rhesus monkeys (M. mulatta) were housed side by side in modular cages that could be configured to provide visual, auditory, and olfactory stimuli provided by another monkey located in the other side of the paired unit. During the first experiment, monkeys self-administered PCP (0.25 mg/ml) and water under concurrent fixed ratio (FR) 16 schedules of reinforcement with either a solid or a grid (social) partition separating each pair of monkeys. In the second experiment, a PCP concentration-response relationship was determined under concurrent progressive ratio (PR) schedules of reinforcement under the solid and grid partition conditions. Under the concurrent FR 16 schedules, PCP and water self-administration was significantly higher during exposure to a cage mate through a grid partition than when a solid partition separated the monkeys. The relative reinforcing strength of PCP, as measured by PR break points, was greater during the grid partition condition compared to the solid partition condition indicated by an upward shift in the concentration-response curve. To determine whether the social stimuli provided by another monkey led to activation of the hypothalamic-pituitary-adrenal (HPA) axis, which may have evoked the increase of PCP self-administration during the grid partition condition, a third experiment was conducted to examine cortisol levels under the two housing conditions. A modest, but nonsignificant increase in cortisol levels was found upon switching from the solid to the grid partition condition. The results suggest that social stimulation among monkeys in adjoining cages leads to enhanced reinforcing strength of PCP. PMID:17560636

Architecture of clathrin fullerene cages reflects a geometric constraint--the head-to-tail exclusion rule--and a preference for asymmetry.

PubMed

Schein, Stan

2009-03-27

Fullerene cages have n trivalent vertices, 12 pentagonal faces, and (n-20)/2 hexagonal faces. The smallest cage in which all of the pentagons are surrounded by hexagons and thus isolated from each other has 60 vertices and is shaped like a soccer ball. The protein clathrin self-assembles into fullerene cages of a variety of sizes and shapes, including smaller ones with adjacent pentagons as well as larger ones, but the variety is limited. To explain the range of clathrin architecture and how these fullerene cages self-assemble, we proposed a hypothesis, the "head-to-tail exclusion rule" (the "Rule"). Of the 5769 small clathrin cage isomers with n< or =60 vertices and adjacent pentagons, the Rule permits just 15, three identified in 1976 and 12 others. A "weak version" of the Rule permits another 99. Based on cryo-electron tomography, Cheng et al. reported six raw clathrin fullerene cages. One was among the three identified in 1976. Here, (1) we identify the remaining five. (2) Four are new and are among the 12 others permitted by the Rule. (3) One, also new, is among the 99 weak version cages. (4) Of particular note, none of the remaining 5565 excluded cages has been identified. These findings provide powerful experimental confirmation of the Rule and the principle on which it is based. (5) Surprisingly, the newly identified clathrin cages are among the least symmetric of those permitted. (6) By devising a method for counting assembly paths, (7) we show that asymmetric cages can be assembled by larger numbers of paths, thus providing a kinetic explanation for the prevalence of asymmetric cages. (8) Finally, we show that operation during cage growth of the Rule greatly increases the likelihood of producing a closed fullerene cage, specifically one of those permitted, but efficient assembly still appears to require internal remodeling.

The influence of fish cage aquaculture on pelagic carbon flow and water chemistry in tidally dominated mangrove estuaries of peninsular Malaysia.

PubMed

Alongi, D M; Chong, V C; Dixon, P; Sasekumar, A; Tirendi, F

2003-05-01

The impact of floating net cages culturing the seabass, Lates calcarifer, on planktonic processes and water chemistry in two heavily used mangrove estuaries in Malaysia was examined. Concentrations of dissolved inorganic and particulate nutrients were usually greater in cage vs. adjacent (approximately 100 m) non-cage waters, although most variability in water-column chemistry related to water depth and tides. There were few consistent differences in plankton abundance, production or respiration between cage and non-cage sites. Rates of primary production were low compared with rates of pelagic mineralization reflecting high suspended loads coupled with large inputs of organic matter from mangrove forests, fishing villages, fish cages, pig farms and other industries within the catchment. Our preliminary sampling did not reveal any large-scale eutrophication due to the cages. A crude estimate of the contribution of fish cage inputs to the estuaries shows that fish cages contribute only approximately 2% of C but greater percentages of N (32-36%) and P (83-99%) to these waters relative to phytoplankton and mangrove inputs. Isolating and detecting impacts of cage culture in such heavily used waterways--a situation typical of most mangrove estuaries in Southeast Asia--are constrained by a background of large, highly variable fluxes of organic material derived from extensive mangrove forests and other human activities. Copyright 2002 Elsevier Science B.V.

Genetic characteristics of Streptococcus dysgalactiae isolated from cage cultured cobia, Rachycentron canadum (L.).

PubMed

Tsai, M-A; Wang, P-C; Yoshida, T; Chen, S-C

2015-12-01

Disease outbreaks occurred during 2007-2013 in Taiwan with 2.5-10% mortality among the cage cultured cobia, Rachycentron canadum (L.), characterized by the presence of polyserositis, pericarditis and peritonitis. The micro-organisms isolated from internal organs were Gram-positive cocci. The isolates were confirmed as Streptococcus dysgalactiae by a polymerase chain reaction assay that yielded the expected specific 259 bp amplicon. Additionally, partial sequence of the 16S-23S rDNA intergenic spacer region of the GCS strain isolates from fish was also compared and produced 100% sequence identity with S. dysgalactiae (GenBank accession number AB252398). The genetic characterization was then determined by pulsed-field gel electrophoresis (PFGE) analysis. Based on PFGE, the Apa I or Sma I digestion patterns of chromosomal DNA of these isolates were grouped into three main clusters. Taiwanese strains were divided into two clusters, and the tet(M) gene was detected in cluster 1 (pulsotypes: A1-A2 and S1-S3), but not in cluster 2 strains (pulsotypes: A3-A4 and S4-S5). Three Japanese strains from amberjack, Seriola dumerili (Risso), were grouped into cluster 3 (pulsotypes: A5-A7 and S6-S8) and displayed no mortality to cobia in the challenge experiment. Conversely, Taiwanese strains from cobia and snubnose pompano, Trachinotus blochii (L.), displayed a mortality rate of 50-87.5% in cobia. © 2014 John Wiley & Sons Ltd.

Swimming with a cage: low-Reynolds-number locomotion inside a droplet.

PubMed

Reigh, Shang Yik; Zhu, Lailai; Gallaire, François; Lauga, Eric

2017-05-03

Inspired by recent experiments using synthetic microswimmers to manipulate droplets, we investigate the low-Reynolds-number locomotion of a model swimmer (a spherical squirmer) encapsulated inside a droplet of a comparable size in another viscous fluid. Meditated solely by hydrodynamic interactions, the encaged swimmer is seen to be able to propel the droplet, and in some situations both remain in a stable co-swimming state. The problem is tackled using both an exact analytical theory and a numerical implementation based on a boundary element method, with a particular focus on the kinematics of the co-moving swimmer and the droplet in a concentric configuration, and we obtain excellent quantitative agreement between the two. The droplet always moves slower than a swimmer which uses purely tangential surface actuation but when it uses a particular combination of tangential and normal actuations, the squirmer and droplet are able to attain the same velocity and stay concentric for all times. We next employ numerical simulations to examine the stability of their concentric co-movement, and highlight several stability scenarios depending on the particular gait adopted by the swimmer. Furthermore, we show that the droplet reverses the nature of the far-field flow induced by the swimmer: a droplet cage turns a pusher swimmer into a puller, and vice versa. Our work sheds light on the potential development of droplets as self-contained carriers of both chemical content and self-propelled devices for controllable and precise drug deliveries.

Performance and welfare of rabbit does in various caging systems.

PubMed

Mikó, A; Matics, Zs; Gerencsér, Zs; Odermatt, M; Radnai, I; Nagy, I; Szendrő, K; Szendrő, Zs

2014-07-01

The objective of the study was to compare production and welfare of rabbit does and their kits housed in various types of cages. Female rabbits were randomly allocated to four groups with the following cage types: CN: common wire-mesh flat-deck cage, without footrest; CF: cage similar to the CN but with plastic footrest; ECWP: enlarged cage with wire-mesh platform; and ECPP: extra enlarged cage with plastic-mesh platform. All does were inseminated on the same day, 11 days after kindlings. Reproductive performance was evaluated during the first five consecutive kindlings. Severity of sore hocks was scored at each insemination. Location preference of the does and the platform usage of their kits were evaluated. Kindling rate, litter size (total born, born alive, alive at 21 and 35 days) and kit mortality were not significantly influenced by the cage types. The litter weight at 21 days was higher in ECWP and ECPP cages than in the CF group (3516, 3576 and 3291 g, respectively; P2.5 cm) and 3 to 4 (3=callus opened, cracks present; 4=wounds) were 58%, 60%, 78% and 48%, and 0%, 5%, 0% and 48% in groups ECPP, ECWP, CF and CN, respectively. Higher number of daily nest visits was observed for CF does than for ECWP does (12.5 v. 5.9; P2/day) was higher in the CF group than in the ECWP group (12.1 v. 3.2%; P<0.01). Within large cages, the does were observed on the platform more frequently in the ECPP cages compared with the ECWP cages (56.9% v. 31.7%; P<0.001). Similarly, 2.7% and 0.2% of kits at 21 days of age, and 33.2% and 5.2% of kits at 28 days of age, were found on the platforms of ECPP and ECWP cages, respectively. In conclusion, cages larger than the conventional ones improved kits' weaning weight, plastic footrests and plastic-mesh platforms in conventional and/or large cages reduced sore hocks' problems, plastic-mesh platforms were more used by both does and kits compared with the wire-mesh platforms.

Stand-alone lumbar cage subsidence: A biomechanical sensitivity study of cage design and placement.

PubMed

Calvo-Echenique, Andrea; Cegoñino, José; Chueca, Raúl; Pérez-Del Palomar, Amaya

2018-08-01

Spinal degeneration and instability are commonly treated with interbody fusion cages either alone or supplemented with posterior instrumentation with the aim to immobilise the segment and restore intervertebral height. The purpose of this work is to establish a tool which may help to understand the effects of intervertebral cage design and placement on the biomechanical response of a patient-specific model to help reducing post-surgical complications such as subsidence and segment instability. A 3D lumbar functional spinal unit (FSU) finite element model was created and a parametric model of an interbody cage was designed and introduced in the FSU. A Drucker-Prager Cap plasticity formulation was used to predict plastic strains and bone failure in the vertebrae. The effect of varying cage size, cross-sectional area, apparent stiffness and positioning was evaluated under 500 N preload followed by 7.5 Nm multidirectional rotation and the results were compared with the intact model. The most influential cage parameters on the FSU were size, curvature congruence with the endplates and cage placement. Segmental stiffness was higher when increasing the cross-sectional cage area in all loading directions and when the cage was anteriorly placed in all directions but extension. In general, the facet joint forces were reduced by increasing segmental stiffness. However, these forces were higher than in the intact model in most of the cases due to the displacement of the instantaneous centre of rotation. The highest plastic deformations took place at the caudal vertebra under flexion and increased for cages with greater stiffness. Thus, wider cages and a more anteriorly placement would increase the volume of failed bone and, therefore, the risk of subsidence. Cage geometry plays a crucial role in the success of lumbar surgery. General considerations such as larger cages may be applied as a guideline, but parameters such as curvature or cage placement should be determined for each specific patient. This model provides a proof-of-concept of a tool for the preoperative evaluation of lumbar surgical outcomes. Copyright © 2018 Elsevier B.V. All rights reserved.

Experimental evidence supports the abscess theory of development of radicular cysts.

PubMed

Nair, P N R; Sundqvist, Göran; Sjögren, Ulf

2008-08-01

The objective of this study was to experimentally induce inflammatory cysts in an animal model so as to test the hypothesis that radicular cysts develop via the "abscess pathway." Twenty-eight perforated custom-made Teflon cages were surgically implanted into defined locations in the back of 7 Sprague Dawley rats. A week after the implantation of the cages, a known quantity of freshly grown, close allogeneic oral keratinocytes in phosphate buffer solution (PBS) was injected into each cage. One cage per animal was treated as the control that received only epithelial cells. The remaining 3 cages of each animal were trials. Seven days post epithelial cell inoculation; a suspension of 0.2 mL of Fusobacterium nucleatum (10(8) bacteria per mL) was injected into each of the 3 trial cages. Two, 12, and 24 weeks after the inoculation of the bacteria, the cages were taken out, and the tissue contents were fixed and processed by correlative light and transmission electron microscopy. Sixteen of the 21 trial cages could be processed and yielded results. Inoculations of epithelial cells followed 1 week later by F. nucleatum into tissue cages resulted in the development inflammatory cysts in 2 of the 16 cages. The 2 cages contained a total of 4 cystic sites. None of the control cages showed the presence of any cyst-like pathology. Inflammatory cysts were induced by initiating acute inflammatory foci (abscess/necrotic area) by bacterial injection that got enclosed by a proliferating epithelium. This finding provides strong experimental evidence in support of the "abscess theory" of development of radicular cysts.

Bisphenol A is released from used polycarbonate animal cages into water at room temperature

USGS Publications Warehouse

Howdeshell, Kembra L.; Peterman, Paul H.; Judy, Barbara M.; Taylor, Julia A.; Orazio, Carl E.; Ruhlen, Rachel L.; vom Saal, Frederick S.; Welshons, Wade V.

2003-01-01

Bisphenol A (BPA) is a monomer with estrogenic activity that is used in the production of food packaging, dental sealants, polycarbonate plastic, and many other products. The monomer has previously been reported to hydrolyze and leach from these products under high heat and alkaline conditions, and the amount of leaching increases as a function of use. We examined whether new and used polycarbonate animal cages passively release bioactive levels of BPA into water at room temperature and neutral pH. Purified water was incubated at room temperature in new polycarbonate and polysulfone cages and used (discolored) polycarbonate cages, as well as control (glass and used polypropylene) containers. The resulting water samples were characterized with gas chromatography/mass spectrometry (GC/MS) and tested for estrogenic activity using an MCF-7 human breast cancer cell proliferation assay. Significant estrogenic activity, identifiable as BPA by GC/MS (up to 310 micro g/L), was released from used polycarbonate animal cages. Detectable levels of BPA were released from new polycarbonate cages (up to 0.3 micro g/L) as well as new polysulfone cages (1.5 micro g/L), whereas no BPA was detected in water incubated in glass and used polypropylene cages. Finally, BPA exposure as a result of being housed in used polycarbonate cages produced a 16% increase in uterine weight in prepubertal female mice relative to females housed in used polypropylene cages, although the difference was not statistically significant. Our findings suggest that laboratory animals maintained in polycarbonate and polysulfone cages are exposed to BPA via leaching, with exposure reaching the highest levels in old cages.

Electrostatic antenna space environment interaction study

NASA Technical Reports Server (NTRS)

Katz, I.

1981-01-01

The interactions of the electrostatic antenna with the space environment in both low Earth orbit and geosynchronous orbit are investigated. It is concluded that the electrostatically controlled membrane mirror is a viable concept for space applications. However, great care must be taken to enclose the high voltage electrodes in a Faraday cage structure to separate the high voltage region from the ambient plasma. For this reason, metallized cloth is not acceptable as a membrane material. Conventional spacecraft charging at geosynchronous orbit should not be a problem provided ancillary structures (such as booms) are given nonnegligible conductivity and adequate grounding. Power loss due to plasma electrons entering the high field region is a potentially serious problem. In low earth orbit any opening whatever in the Faraday cage is likely to produce an unacceptable power drain.

Theoretical studies of large water clusters: (H2O)28, (H2O)29, (H2O)30, and (H2O)31 hexakaidecahedral structures

NASA Astrophysics Data System (ADS)

Khan, Arshad

1997-04-01

The 28, 29, 30, and 31 mer hexakaidecahedral water clusters were studied by applying the intermediate neglect of differential overlap self-consistent field restricted Hartree-Fock method (INDO SCF RHF) after parametrization for H and O atoms. The most stable 29 and 30 mer clusters have one and two water molecules, respectively within the cavity of the distorted hexakaidecahedral cage with stabilization energy/monomer values of around 10.9 and 11.0 kcal, respectively. The 31 mer cluster with three water molecules within the cavity is less stable than the isomer with two molecules within the cavity and the third one bonded outside of the cage by around 3 kcal/mol.

Microglial activation as a measure of stress in mouse brains exposed acutely (60 minutes) and long-term (2 years) to mobile telephone radiofrequency fields.

PubMed

Finnie, John W; Cai, Zhao; Manavis, Jim; Helps, Stephen; Blumbergs, Peter C

2010-02-01

To determine whether acute or long-term exposure of the brain to mobile telephone radiofrequency (RF) fields produces activation of microglia, which normally respond rapidly to any change in their microenvironment. Using a purpose designed exposure system at 900 MHz, mice were given a single, far-field whole body exposure at a specific absorption rate (SAR) of 4 W/kg for 60 min (acute) or on five successive days per week for 104 weeks (long-term). Control mice were sham-exposed or freely mobile in a cage to control for any stress caused by immobilisation in the exposure module. Positive control brains subjected to a stab wound were also included to confirm the ability of microglia to react to any neural stress. Brains were perfusion-fixed with 4% paraformaldehyde and representative regions of the cerebral cortex and hippocampus immunostained for ionised calcium binding adaptor molecule (Iba1), a specific microglial marker. There was no increase in microglial Iba1 expression in brains short or long-term exposed to mobile telephony microwaves compared to control (sham-exposed or freely moving caged mice) brains, while substantial microglial activation occurred in damaged positive control neural tissue. Acute (60 minutes) or longer duration (2 years) exposure of murine brains to mobile telephone RF fields did not produce any microglial activation detectable by Iba1 immunostaining.

Effects of environmental enrichment on the activity of the amygdala in micrencephalic rats exposed to a novel open field.

PubMed

Matsuda, Wakoto; Ehara, Ayuka; Nakadate, Kazuhiko; Yoshimoto, Kanji; Ueda, Shuichi

2018-01-01

Environmental enrichment (EE) mediates recovery from sensory, motor, and cognitive deficits and emotional abnormalities. In the present study, we examined the effects of EE on locomotor activity and neuronal activity in the amygdala in control and methylazoxymethanol acetate (MAM)-induced micrencephalic rats after challenge in a novel open field. Control rats housed in EE (CR) showed reduced locomotor activity compared to rats housed in a conventional cage (CC), whereas hyperactivity was seen in MAM rats housed in a conventional cage (MC) and in MAM rats housed in EE (MR). Novel open field exposure in both CC and MC resulted in a marked increase in Fos expression in the anterior and posterior parts of the basolateral amygdaloid nucleus, basomedial nucleus, and medial nucleus, whereas these increases in expression were not observed in CR. The effect of EE on Fos expression in the amygdala was different in MR exposed to a novel open field compared to CR. Furthermore, we observed a quite different pattern of Fos expression in the central nucleus of the amygdala between control and MAM rats. The present results suggest that neuronal activity in the amygdala that responds to anxiety is altered in MAM rats, especially when the rats are reared in EE. These alterations may cause behavioral differences between control and MAM rats. © 2017 Japanese Teratology Society.

Do Organic Amendments Enhance the Nematode-Trapping Fungi Dactylellina haptotyla and Arthrobotrys oligospora?

PubMed

Jaffee, B A

2004-09-01

Soil cages (polyvinyl chloride pipe with mesh-covered ends) were used to determine how the quantity of two organic amendments affected the nematode-trapping fungi Dactylellina haptotyla and Arthrobotrys oligospora, which were studied independently in two different vineyards. Each cage contained 80 cm(3) of field soil (120 g dry weight equivalent), fungal inoculum (two alginate pellets, each weighing 1.9 mg and containing assimilative hyphae of one fungus), and dried grape or alfalfa leaves (0, 360, or 720 mg equivalent to 0, 4,500, or 9,000 kg/ha) with a C:N of 28:1 and 8:1, respectively. Cages were buried in the vineyards, recovered after 25 to 39 days, and returned to the laboratory where fungus population density and trapping were quantified. Dactylellina haptotyla population density and trapping were most enhanced by the smaller quantity of alfalfa amendment and were not enhanced by the larger quantity of alfalfa amendment. Arthrobotrys oligospora population density was most enhanced by the larger quantity of alfalfa amendment, but A. oligospora trapped few or no nematodes, regardless of amendment. Trapping and population density were correlated for D. haptotyla but not for A. oligospora.

A microcontroller-based telemetry system for sympathetic nerve activity and ECG measurement.

PubMed

Harada, E; Yonezawa, Y; Caldwell, W M; Hahn, A W

1999-01-01

A telemetry system employing a low power 8-bit microcontroller has been developed for chronic unanesthetized small animal studies. The two-channel system is designed for use with animals in shielded cages. Analog signals from implantable ECG and nerve electrodes are converted to an 8-bit serial digital format. This is accomplished by individual 8 bit A/D converters included in the microcontroller, which also has serial I/O port. The converted serial binary code is applied directly to an antenna wire. Therefore, the system does not need to employ a separate transmitter, such as in FM or infrared optical telemeters. The system is used in a shielded animal cage to reduce interference from external radio signals and 60 Hz power line fields. The code is received by a high input impedance amplifier in the cage and is then demodulated. The telemeter is powered by a small 3 V lithium battery, which provides 100 hours of continuous operation. The circuit is constructed on two 25 x 25 mm. printed circuit boards and encapsulated in epoxy, yielding a total volume of 6.25 cc. The weight is 15 g.

Field evaluation of poultry red mite (Dermanyssus gallinae) native and recombinant prototype vaccines.

PubMed

Bartley, Kathryn; Turnbull, Frank; Wright, Harry W; Huntley, John F; Palarea-Albaladejo, Javier; Nath, Mintu; Nisbet, Alasdair J

2017-09-15

Vaccination is a desirable emerging strategy to combat poultry red mite (PRM), Dermanyssus gallinae. We performed trials, in laying hens in a commercial-style cage facility, to test the vaccine efficacy of a native preparation of soluble mite extract (SME) and of a recombinant antigen cocktail vaccine containing bacterially-expressed versions of the immunogenic SME proteins Deg-SRP-1, Deg-VIT-1 and Deg-PUF-1. Hens (n=384 per group) were injected with either vaccine or adjuvant only (control group) at 12 and 17 weeks of age and then challenged with PRM 10days later. PRM counts were monitored and, at the termination of the challenge period (17 weeks post challenge), average PRM counts in cages containing birds vaccinated with SME were reduced by 78% (p<0.001), compared with those in the adjuvant-only control group. When the trial was repeated using the recombinant antigen cocktail vaccine, no statistically significant differences in mean PRM numbers were observed in cages containing vaccinated or adjuvant-only immunised birds. The roles of antigen-specific antibody levels and duration in providing vaccine-induced and exposure-related protective immunity are discussed. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Direct evidence of spatially selective iron mineralization using an immobilized ferritin protein cage.

PubMed

Uto, Koichiro; Yamamoto, Kazuya; Kishimoto, Naoko; Muraoka, Masahiro; Aoyagi, Takao; Yamashita, Ichiro

2014-04-01

(Apo)ferritins are cage-shaped proteins which have recently received a great deal of attention because the inner cavity of the protein shell can be used as a size-restricted reaction field for the synthesis of nanomaterials. The biomineralization behavior and inorganic nanoparticle (NP) synthesis mechanism of (apo)ferritin in solution systems have been studied but the mineralization behavior of (apo)ferritin on the substrates has not yet been well studied. Here, we conducted quantitative and kinetic analyses of the mineralization behavior of immobilized (apo)ferritin on a polyelectrolyte multilayer (PEM) using quartz crystal microbalance (QCM), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) techniques. We demonstrated that the (apo)ferritin immobilized on a substrate synthesizes a ferrihydrite core within the confines of the protein cage; similar to a solution dispersed system. In addition, we applied a ferritin/apoferritin blended monolayer to the study of iron mineralization and revealed that biomineralization in this system is spatially selective. It is important to understand the mineralization mechanisms for the synthesis of other functional NPs as this approach has potential for a broad range of magnetic, catalytic, and biomedical sensing applications.

Evaluating Weeds as Hosts of Tomato yellow leaf curl virus.

PubMed

Smith, Hugh A; Seijo, Teresa E; Vallad, Gary E; Peres, Natalia A; Druffel, Keri L

2015-08-01

Bemisia tabaci (Gennadius) biotype B transmits Tomato yellow leaf curl virus (TYLCV), which affects tomato production globally. Prompt destruction of virus reservoirs is a key component of virus management. Identification of weed hosts of TYLCV will be useful for reducing such reservoirs. The status of weeds as alternate hosts of TYLCV in Florida remains unclear. In greenhouse studies, B. tabaci adults from a colony reared on TYLCV-infected tomato were established in cages containing one of four weeds common to horticultural fields in central and south Florida. Cages containing tomato and cotton were also infested with viruliferous whiteflies as a positive control and negative control, respectively. Whitefly adults and plant tissue were tested periodically over 10 wk for the presence of TYLCV using PCR. After 10 wk, virus-susceptible tomato plants were placed in each cage to determine if whiteflies descended from the original adults were still infective. Results indicate that Bidens alba, Emilia fosbergii, and Raphanus raphanistrum are not hosts of TYLCV, and that Amaranthus retroflexus is a host. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Evaluation of cucurbitacin-based gustatory stimulant to facilitate cucumber beetle (Coleoptera: Chrysomelidae) management with foliar insecticides in melons.

PubMed

Pedersen, Andrew B; Godfrey, Larry D

2011-08-01

The bitter plant-derived compounds cucurbitacins are known to stimulate feeding of adult cucumber beetles (Coleoptera: Chrysomelidae). A cucurbitacin-based gustatory stimulant applied as a flowable bait combined with either spinosad or carbaryl was compared with foliar sprays of spinosad and carbaryl for controlling two cucumber beetle species (Diabrotica undecimpunctata undecimpunctata Mannerheim and Acalymma trivittatum Mannerheim) in honeydew melons (Cucumis melo L.). Field studies were conducted on the University of California-Davis plant pathology farm in 2008 and 2009. Beetle densities after applications and fruit damage from beetle feeding were compared among treatments. In addition, beetle survival was compared within field cages placed over the treated foliage infested with beetles. Using all three measures of efficacy, we determined that the addition of cucurbitacin bait had no effect on the level of cucumber beetle control with carbaryl in either 2008 or 2009. In both years, spinosad did not significantly reduce cucumber beetle densities in either field cages or field plots and did not reduce fruit damage relative to the untreated control. The addition of the bait to spinosad did not improve its efficacy. A laboratory bioassay of the spinosad formulation used in the field showed it had significant lethal effects on adults of both cucumber beetle species. Results indicated that the bait formulation used did not improve cucumber beetle control but may benefit from the addition of floral attractants or using a different type of cucurbitacin.

Interspecific competition between Snellenius manilae and Meteorus pulchricornis, larval parasitoids of Spodoptera litura.

PubMed

Chen, W-T; Hwang, S-Y

2015-10-01

Snellenius manilae (Ashmead) and Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) are larval endoparasitoids of Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae). Both species preferentially parasitize early-instar S. litura and occupy similar ecological niches. Therefore, competition between the two species may occur. In this study, intrinsic competition and cage experiments were conducted to discuss the interactions between S. manilae and M. pulchricornis. The results indicated that in intrinsic competition, M. pulchricornis was always the dominant species. In cage experiments, when the total number of parasitoids was four, the parasitism rates following the release of one species were significantly higher than the release of two species simultaneously. In addition, parasitism rate of eight M. pulchricornis was also significantly higher than the parasitism rate of the treatment released four S. manilae and four M. pulchricornis simultaneously. Therefore, competition occurs between S. manilae and M. pulchricornis, and M. pulchricornis is typically the superior of the two species. The use of M. pulchricornis as a biological agent for S. litura should be considered.

BIOCHEMICAL AND ANALYTICAL CHARACTERIZATION OF ESTROGENICALLY ACTIVE WASTEWATER: COMPARISON OF FIELD EXTRAPOLATIONS TO THE MEASURED CONCENTRATION OF ESTROGENS IN SEWAGE EFFLUENT

EPA Science Inventory

Estrogenically active wastewater was observed at two municipal wastewater treatment plants (WWTPs) utilizing caged male channel catfish in a previous study. The focus of this investigation was to identify and characterize the compound(s) responsible for this estrogenic response. ...

Relative longevity of adult Nezara viridula in field cages of cotton, peanut, and soybean

USDA-ARS?s Scientific Manuscript database

Recent evidence shows that southern green stink bugs use peanut as a reproductive host and adults colonize and feed in peanut, sometimes extensively. Stink bugs prefer the seeds/fruit of host plants and the fruiting structures in peanut are underground and unavailable. Therefore, it is not clear th...

Exposure of Primates for One Year to Electric and Magnetic Fields Associated with ELF Communications Systems.

DTIC Science & Technology

1977-11-01

row of A cages. Direct light reached the animal after passing through two layers of plexiglass that were designed to pass the full spectrum. The...the serum PHI activity. Blood Urea Nitrogen (BUN) Urease converted urea Into ammonia and carbon dioxide. Glutamic dehydrogenase catalyzed the

Lack of establishment of the Mediterranean tamarisk beetle Diorhabda elongata (Coleoptera: Chrysomelidae) on athel (Tamarix aphylla) (Tamaricaceae) in south Texas

USDA-ARS?s Scientific Manuscript database

Adult Mediterranean tamarisk beetles, Diorhabda elongata (Brullé), a defoliator of exotic saltcedar (Tamarix spp.), were released into four field cages containing small saltcedar trees or closely-related exotic athel trees (Tamarix aphylla (L.). Karsten) and onto uncaged beneficial mature athel tree...

Missing in the Youth Development Literature: The Organization as Host, Cage, and Promise

ERIC Educational Resources Information Center

Roholt, Ross VeLure; Baizerman, Michael; Rana, Sheetal; Korum, Kathy

2013-01-01

Good, high-quality youth development programs require effective youth organizations. While youth organizations are commonly understood as valuable and supportive of healthy youth development, attention and focus on youth organizations in both scholarship and practice are missing within the youth development field. The authors advocate for a more…

Linear diffusion into a Faraday cage.

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

Warne, Larry Kevin; Lin, Yau Tang; Merewether, Kimball O.

2011-11-01

Linear lightning diffusion into a Faraday cage is studied. An early-time integral valid for large ratios of enclosure size to enclosure thickness and small relative permeability ({mu}/{mu}{sub 0} {le} 10) is used for this study. Existing solutions for nearby lightning impulse responses of electrically thick-wall enclosures are refined and extended to calculate the nearby lightning magnetic field (H) and time-derivative magnetic field (HDOT) inside enclosures of varying thickness caused by a decaying exponential excitation. For a direct strike scenario, the early-time integral for a worst-case line source outside the enclosure caused by an impulse is simplified and numerically integrated tomore » give the interior H and HDOT at the location closest to the source as well as a function of distance from the source. H and HDOT enclosure response functions for decaying exponentials are considered for an enclosure wall of any thickness. Simple formulas are derived to provide a description of enclosure interior H and HDOT as well. Direct strike voltage and current bounds for a single-turn optimally-coupled loop for all three waveforms are also given.« less

Prenatal exposure to moderate levels of ethanol alters social behavior in adult rats: relationship to structural plasticity and immediate early gene expression in frontal cortex.

PubMed

Hamilton, Derek A; Akers, Katherine G; Rice, James P; Johnson, Travis E; Candelaria-Cook, Felicha T; Maes, Levi I; Rosenberg, Martina; Valenzuela, C Fernando; Savage, Daniel D

2010-03-05

The goals of the present study were to characterize the effects of prenatal exposure to moderate levels of ethanol on adult social behavior, and to evaluate fetal-ethanol-related effects on dendritic morphology, structural plasticity and activity-related immediate early gene (IEG) expression in the agranular insular (AID) and prelimbic (Cg3) regions of frontal cortex. Baseline fetal-ethanol-related alterations in social behavior were limited to reductions in social investigation in males. Repeated experience with novel cage-mates resulted in comparable increases in wrestling and social investigation among saccharin- and ethanol-exposed females, whereas social behavioral effects among males were more evident in ethanol-exposed animals. Male ethanol-exposed rats also displayed profound increases in wrestling when social interaction was motivated by 24h of isolation. Baseline decreases in dendritic length and spine density in AID were observed in ethanol-exposed rats that were always housed with the same cage-mate. Modest experience-related decreases in dendritic length and spine density in AID were observed in saccharin-exposed rats housed with various cage-mates. In contrast, fetal-ethanol-exposed rats displayed experience-related increases in dendritic length in AID, and no experience-related changes in spine density. The only effect observed in Cg3 was a baseline increase in basilar dendritic length among male ethanol-exposed rats. Robust increases in activity-related IEG expression in AID (c-fos and Arc) and Cg3 (c-fos) were observed following social interaction in saccharin-exposed rats, however, activity-related increases in IEG expression were not observed in fetal-ethanol-exposed rats in either region. The results indicate that deficits in social behavior are among the long-lasting behavioral consequences of moderate ethanol exposure during brain development, and implicate AID, and to a lesser degree Cg3, in fetal-ethanol-related social behavior abnormalities. Copyright 2009 Elsevier B.V. All rights reserved.

Molecular marriage through partner preferences in covalent cage formation and cage-to-cage transformation.

PubMed

Acharyya, Koushik; Mukherjee, Sandip; Mukherjee, Partha Sarathi

2013-01-16

Unprecedented self-sorting of three-dimensional purely organic cages driven by dynamic covalent bonds is described. Four different cages were first synthesized by condensation of two triamines and two dialdehydes separately. When a mixture of all the components was allowed to react, only two cages were formed, which suggests a high-fidelity self-recognition. The issue of the preference of one triamine for a particular dialdehyde was further probed by transforming a non-preferred combination to either of the two preferred combinations by reacting it with the appropriate triamine or dialdehyde.

A stochastic frontier analysis of technical efficiency of fish cage culture in Peninsular Malaysia.

PubMed

Islam, Gazi Md Nurul; Tai, Shzee Yew; Kusairi, Mohd Noh

2016-01-01

Cage culture plays an important role in achieving higher output and generating more export earnings in Malaysia. However, the cost of fingerlings, feed and labour have increased substantially for cage culture in the coastal areas in Peninsular Malaysia. This paper uses farm level data gathered from Manjung, Perak and Kota Tinggi, Johor to investigate the technical efficiency of brackish water fish cage culture using the stochastic frontier approach. The technical efficiency was estimated and specifically the factors affecting technical inefficiencies of fish cage culture system in Malaysia was investigated. On average, 37 percent of the sampled fish cage farms are technically efficient. The results suggest very high degrees of technical inefficiency exist among the cage culturists. This implies that great potential exists to increase fish production through improved efficiency in cage culture management in Peninsular Malaysia. The results indicate that farmers obtained grouper fingerlings from other neighboring countries due to scarcity of fingerlings from wild sources. The cost of feeding for grouper (Epinephelus fuscoguttatus) requires relatively higher costs compared to seabass (Lates calcarifer) production in cage farms in the study areas. Initiatives to undertake extension programmes at the farm level are needed to help cage culturists in utilizing their resources more efficiently in order to substantially enhance their fish production.

The Benefit of Additional Oviposition Targets for a Polyphagous Butterfly

PubMed Central

Johansson, Josefin; Bergström, Anders; Janz, Niklas

2007-01-01

While the reasons for the prevalence of specialists over generalists among herbivorous insects have been at the focus of much interest, less effort has been put into understanding the polyphagous exceptions. Recent studies have suggested that these exceptions may be important for insect diversification, which calls for a better understanding of the potential factors that can lead to an increased host plant repertoire. Females of the Nymphalid butterfly, Polygonia c-album, were used to test if egg output and/or likelihood of finding a host increased with the addition of a secondary host. There was no effect of prior eggs on the host for willingness to oviposit on a plant. The main experiments were conducted both in small laboratory cages and in large outdoor experimental arenas. No positive effect was found when another oviposition target was added in small cages in the laboratory. On the other hand, in the outdoor arenas the females more often found a host to oviposit on and had a higher egg output when they had access to an additional host, even though the second host was lower in their preference hierarchy. The difference between these experiments was attributed to searching for acceptable host plants within a patch, a factor that was included in the large cages but not in the small. When host availability is limited, adding oviposition targets can potentially act to counterbalance specialization and thus favor the evolution of generalization. PMID:20334600

Entering and exiting behaviour of the phlebotomine sand fly Lutzomyia longiflocosa (Diptera: Psychodidae) in rural houses of the sub-Andean region of Colombia

PubMed Central

Pardo, Raúl Hernando; Santamaría, Erika; Cabrera, Olga Lucia

2016-01-01

The present study identified the entering and exiting sites for Lutzomyia longiflocosa in rural houses of the sub-Andean region in Colombia. Entering sites were identified with sticky traps set up outside the bedrooms, around the eave openings, and with cage traps enclosing the slits in the doors and windows inside the bedrooms. Exiting sites were identified by releasing groups of females indoors. These females were blood fed and marked with fluorescent powders. Females were recaptured with the trap placement described above but set up on the opposite sides of the openings. In the entering experiment, a significantly higher number of females were captured in the sticky traps at the zone nearest the eave openings (n = 142) than those captured in the other zones of the trap (n = 52); similarly, a higher number of females were captured on the front side of the house (n = 105) than at the rear side (n = 37). Only two females were collected in the cage trap. In the exiting experiment, at the ceiling, the highest percentage (86.2%) of females was recaptured with sticky traps nearest the eave openings and on the front side of the house (70.0%). Seven females were collected in the cage trap. Lu. longiflocosa entered and exited houses primarily through the eave openings in a non-random pattern in relation to the sides of the house. PMID:27925019

Entering and exiting behaviour of the phlebotomine sand fly Lutzomyia longiflocosa (Diptera: Psychodidae) in rural houses of the sub-Andean region of Colombia.

PubMed

Pardo, Raúl Hernando; Santamaría, Erika; Cabrera, Olga Lucia

2017-01-01

The present study identified the entering and exiting sites for Lutzomyia longiflocosa in rural houses of the sub-Andean region in Colombia. Entering sites were identified with sticky traps set up outside the bedrooms, around the eave openings, and with cage traps enclosing the slits in the doors and windows inside the bedrooms. Exiting sites were identified by releasing groups of females indoors. These females were blood fed and marked with fluorescent powders. Females were recaptured with the trap placement described above but set up on the opposite sides of the openings. In the entering experiment, a significantly higher number of females were captured in the sticky traps at the zone nearest the eave openings (n = 142) than those captured in the other zones of the trap (n = 52); similarly, a higher number of females were captured on the front side of the house (n = 105) than at the rear side (n = 37). Only two females were collected in the cage trap. In the exiting experiment, at the ceiling, the highest percentage (86.2%) of females was recaptured with sticky traps nearest the eave openings and on the front side of the house (70.0%). Seven females were collected in the cage trap. Lu. longiflocosa entered and exited houses primarily through the eave openings in a non-random pattern in relation to the sides of the house.

Interactions Between Housing Density and Ambient Temperature in the Cage Environment: Effects on Mouse Physiology and Behavior.

PubMed

Toth, Linda A; Trammell, Rita A; Ilsley-Woods, Megan

2015-11-01

To determine how housing density and ambient temperature interact to influence the physiology and behavior of mice, we systematically varied housing density (1 to 5 mice per cage) and ambient temperature (22, 26, or 30 °C) and measured effects on body weight, food intake, diurnal patterns of locomotor activity and core temperature, fecal corticosterone, and serum cytokine and adipokine panels. Temperatures inside cages housing 5 mice were 1 to 2 °C higher than the ambient temperature. As the housing density decreased, in-cage temperatures began to fall at a density of 2 or 3 mice per cage and did not differ from ambient temperature at 1 mouse per cage. Ambient temperature, but not housing density, significantly affected food intake. Although neither ambient temperature nor housing density affected core temperature or activity, hyperthermia and behavioral activation occurred during the 12-h period after cage change. Fecal concentrations of corticosterone metabolites and serum cytokines, chemokines, insulin, and leptin were not influenced by cage density and were only sporadically influenced by ambient temperature. Our data document that the number of mice housed per cage influences the intracage environmental conditions and that ambient temperature influences food intake even when temperatures are within or near recommended or thermoneutral ranges. We conclude that investigators should be cautious when changing the number of mice housed in a cage over the course of a study, because doing so significantly alters the cage environment to which remaining mice are exposed.

Interactions Between Housing Density and Ambient Temperature in the Cage Environment: Effects on Mouse Physiology and Behavior

PubMed Central

Toth, Linda A; Trammell, Rita A; Ilsley-Woods, Megan

2015-01-01

To determine how housing density and ambient temperature interact to influence the physiology and behavior of mice, we systematically varied housing density (1 to 5 mice per cage) and ambient temperature (22, 26, or 30 °C) and measured effects on body weight, food intake, diurnal patterns of locomotor activity and core temperature, fecal corticosterone, and serum cytokine and adipokine panels. Temperatures inside cages housing 5 mice were 1 to 2 °C higher than the ambient temperature. As the housing density decreased, in-cage temperatures began to fall at a density of 2 or 3 mice per cage and did not differ from ambient temperature at 1 mouse per cage. Ambient temperature, but not housing density, significantly affected food intake. Although neither ambient temperature nor housing density affected core temperature or activity, hyperthermia and behavioral activation occurred during the 12-h period after cage change. Fecal concentrations of corticosterone metabolites and serum cytokines, chemokines, insulin, and leptin were not influenced by cage density and were only sporadically influenced by ambient temperature. Our data document that the number of mice housed per cage influences the intracage environmental conditions and that ambient temperature influences food intake even when temperatures are within or near recommended or thermoneutral ranges. We conclude that investigators should be cautious when changing the number of mice housed in a cage over the course of a study, because doing so significantly alters the cage environment to which remaining mice are exposed. PMID:26632780

Effects of single caging and cage size on behavior and stress level of domestic neutered cats housed in an animal shelter.

PubMed

Uetake, Katsuji; Goto, Akihiro; Koyama, Rumi; Kikuchi, Rieko; Tanaka, Toshio

2013-03-01

Cats need a minimum amount of space even in animal shelters. In this study the effects of single caging and cage size on the behavior and stress level of domestic cats were investigated. Six neutered cats (2-15 years old) that had been housed in a group for at least 7 months were moved to three kinds of single cages (small, medium and large) by rotation on a Latin square design. They experienced each cage size for 6 days. Cats could use vertical dimensions when housed in a group room and the large cage. Behavioral observation was conducted for 3 h in the evening, and stress levels were assessed by urine cortisol-to-creatinine ratios. The amounts (estimated proportions) of time spent in locomotion and social/solitary play were lower even in large cages than in group housing (both P < 0.05). Conversely, the amount of time spent resting tended to increase when housed singly (P = 0.104). The urine cortisol-to-creatinine ratios of singly housed cats tended to be higher than that of group-housed cats (P = 0.086). The results indicate that cats become less active when they are housed singly in cages regardless of the cage size. Cats seem to feel no undue stress even in small cages if the stay is short. © 2012 The Authors. Animal Science Journal © 2012 Japanese Society of Animal Science.

Play Caging Benefits the Behavior of Singly Housed Laboratory Rhesus Macaques (Macaca mulatta)

PubMed Central

Griffis, Caroline M; Martin, Allison L; Perlman, Jaine E; Bloomsmith, Mollie A

2013-01-01

This study addresses a recommendation in The Guide for the Care and Use of Laboratory Animals to provide singly housed nonhuman primates with intermittent access to large, enriched (play) caging. Research on the potential benefits of this type of caging is limited. The present study examines the effects of play caging on behavior, activity, and enrichment use. Singly housed, adult male, rhesus macaques (n = 10) underwent a baseline phase in their home cages, a 2-wk treatment phase with housing in play cages, and a posttreatment phase after returning to their home cages. Each subject underwent focal behavioral observations (n = 10; duration 30 min each) during each study phase, for a total of 150 h of data collection. Results showed increases in locomotion and enrichment use and a trend toward decreased abnormal behavior while subjects were in the play cage, with the durations of these behaviors returning to baseline levels after treatment. Anxiety-related behaviors decreased between the treatment and posttreatment phases but not between baseline and treatment, suggesting that outside factors may have influenced the decline. During the treatment phase, subjects spent more time in the upper quadrants of the play caging and preferred a mirror and forage boards as forms of enrichment. The greatest behavioral improvement occurred during the first week in the play cage. This study provides evidence to support the benefits of play caging for singly housed rhesus macaques. PMID:24041207

Particulate matter in animal rooms housing mice in microisolation caging.

PubMed

Langham, Gregory L; Hoyt, Robert F; Johnson, Thomas E

2006-11-01

Reactions to allergens created by laboratory animals are among the most frequently encountered occupational illnesses associated with research animals. Personnel are exposed to these allergens through airborne particulate matter. Although the use of microisolation caging systems can reduce particulate matter concentrations in rooms housing mice, the operating parameters of ventilated caging systems vary extensively. We compared room air in mouse rooms containing 5 different types of caging: 1) individually ventilated caging under positive pressure with filtered intake air and exhaust air returned to the room (VCR+), 2) individually ventilated caging under negative pressure with exhaust air returned to the room (VCR-), 3) individually ventilated caging under positive pressure with exhaust air returned to the heating, ventilation, and air-conditioning (HVAC) system, 4) individually ventilated caging under negative pressure with exhaust air returned to the HVAC system, and 5) static microisolation cages. We found that rooms under VCR conditions had fewer large particles than did those under other conditions, but the numbers of 0.3 microm particles did not differ significantly among systems. Static, positive or negative pressure applied to caging units as well as route of air exhaust were found to have little influence on the total number of particles in the atmosphere. Therefore, considering the heat load, odor, and overall particulate concentration in the room, placing individually ventilated caging under negative pressure with exhaust air returned to the HVAC system appears to be the optimal overall choice when using microisolation housing for rodents.

Utilization of early soybeans for food and reproduction by the tarnished plant bug (Hemiptera: Miridae) in the delta of Mississippi.

PubMed

Snodgrass, G L; Jackson, R E; Abel, C A; Perera, O P

2010-08-01

Commercially produced maturity group (MG) IV soybeans, Glycine max L., were sampled during bloom for tarnished plant bugs, Lygus lineolaris (Palisot de Beauvois), during May and June 1999 (3 fields) and 2001 (18 fields). The adults and nymphs were found primarily in single population peaks in both years, indicating a single new generation was produced during each year. The peak mean numbers of nymphs were 0.61 and 0.84 per drop cloth sample in 1999 and 2001, respectively. Adults peaked at 3.96 (1999) and 3.76 (2001) per sweep net sample (25 sweeps). Tests using laboratory-reared and field-collected tarnished plant bugs resulted in very poor survival of nymphs on 16 different soybean varieties (MG III, one; IV, four; V, nine; VI, two). A large cage (0.06 ha) field test found that the number of nymphs produced on eight soybean varieties after mated adults were released into the cages was lower than could be expected on a suitable host. These results indicated that soybean was a marginal host for tarnished plant bugs. However, the numbers of adults and nymphs found in the commercially produced fields sampled in the study may have been high enough to cause feeding damage to the flowering soybeans. The nature of the damage and its possible economic importance were not determined. Reproduction of tarnished plant bugs in the commercially produced early soybean fields showed that the early soybeans provided tarnished plant bugs with a very abundant host at a time when only wild hosts were previously available.

Self-assembly of nanosize coordination cages on si(100) surfaces.

PubMed

Busi, Marco; Laurenti, Marco; Condorelli, Guglielmo G; Motta, Alessandro; Favazza, Maria; Fragalà, Ignazio L; Montalti, Marco; Prodi, Luca; Dalcanale, Enrico

2007-01-01

Bottom-up fabrication of 3D organic nanostructures on Si(100) surfaces has been achieved by a two-step procedure. Tetradentate cavitand 1 was grafted on the Si surface together with 1-octene (Oct) as a spatial spectator by photochemical hydrosilylation. Ligand exchange between grafted cavitand 1 and self-assembled homocage 2, derived from cavitand 5 bearing a fluorescence marker, led to the formation of coordination cages on Si(100). Formation, quantification, and distribution of the nanoscale molecular containers on a silicon surface was assessed by using three complementary analytical techniques (AFM, XPS, and fluorescence) and validated by control experiments on cavitand-free silicon surfaces. Interestingly, the fluorescence of pyrene at approximately 4 nm above the Si(100) surface can be clearly observed.

Variation and decomposition of the partial molar volume of small gas molecules in different organic solvents derived from molecular dynamics simulations.

PubMed

Klähn, Marco; Martin, Alistair; Cheong, Daniel W; Garland, Marc V

2013-12-28

The partial molar volumes, V(i), of the gas solutes H2, CO, and CO2, solvated in acetone, methanol, heptane, and diethylether are determined computationally in the limit of infinite dilution and standard conditions. Solutions are described with molecular dynamics simulations in combination with the OPLS-aa force field for solvents and customized force field for solutes. V(i) is determined with the direct method, while the composition of V(i) is studied with Kirkwood-Buff integrals (KBIs). Subsequently, the amount of unoccupied space and size of pre-formed cavities in pure solvents is determined. Additionally, the shape of individual solvent cages is analyzed. Calculated V(i) deviate only 3.4 cm(3) mol(-1) (7.1%) from experimental literature values. Experimental V(i) variations across solutions are reproduced qualitatively and also quantitatively in most cases. The KBI analysis identifies differences in solute induced solvent reorganization in the immediate vicinity of H2 (<0.7 nm) and solvent reorganization up to the third solvation shell of CO and CO2 (<1.6 nm) as the origin of V(i) variations. In all solutions, larger V(i) are found in solvents that exhibit weak internal interactions, low cohesive energy density and large compressibility. Weak internal interactions facilitate solvent displacement by thermal solute movement, which enhances the size of solvent cages and thus V(i). Additionally, attractive electrostatic interactions of CO2 and the solvents, which do not depend on internal solvent interactions only, partially reversed the V(i) trends observed in H2 and CO solutions where electrostatic interactions with the solvents are absent. More empty space and larger pre-formed cavities are found in solvents with weak internal interactions, however, no evidence is found that solutes in any considered solvent are accommodated in pre-formed cavities. Individual solvent cages are found to be elongated in the negative direction of solute movement. This wake behind the moving solute is more pronounced in case of mobile H2 and in solvents with weaker internal interactions. However, deviations from a spherical solvent cage shape do not influence solute-solvent radial distribution functions after averaging over all solvent cage orientations and hence do not change V(i). Overall, the applied methodology reproduces V(i) and its variations reliably and the used V(i) decompositions identify the underlying reasons behind observed V(i) variations.

Variation and decomposition of the partial molar volume of small gas molecules in different organic solvents derived from molecular dynamics simulations

NASA Astrophysics Data System (ADS)

Klähn, Marco; Martin, Alistair; Cheong, Daniel W.; Garland, Marc V.

2013-12-01

The partial molar volumes, bar V_i, of the gas solutes H2, CO, and CO2, solvated in acetone, methanol, heptane, and diethylether are determined computationally in the limit of infinite dilution and standard conditions. Solutions are described with molecular dynamics simulations in combination with the OPLS-aa force field for solvents and customized force field for solutes. bar V_i is determined with the direct method, while the composition of bar V_i is studied with Kirkwood-Buff integrals (KBIs). Subsequently, the amount of unoccupied space and size of pre-formed cavities in pure solvents is determined. Additionally, the shape of individual solvent cages is analyzed. Calculated bar V_i deviate only 3.4 cm3 mol-1 (7.1%) from experimental literature values. Experimental bar V_i variations across solutions are reproduced qualitatively and also quantitatively in most cases. The KBI analysis identifies differences in solute induced solvent reorganization in the immediate vicinity of H2 (<0.7 nm) and solvent reorganization up to the third solvation shell of CO and CO2 (<1.6 nm) as the origin of bar V_i variations. In all solutions, larger bar V_i are found in solvents that exhibit weak internal interactions, low cohesive energy density and large compressibility. Weak internal interactions facilitate solvent displacement by thermal solute movement, which enhances the size of solvent cages and thus bar V_i. Additionally, attractive electrostatic interactions of CO2 and the solvents, which do not depend on internal solvent interactions only, partially reversed the bar V_i trends observed in H2 and CO solutions where electrostatic interactions with the solvents are absent. More empty space and larger pre-formed cavities are found in solvents with weak internal interactions, however, no evidence is found that solutes in any considered solvent are accommodated in pre-formed cavities. Individual solvent cages are found to be elongated in the negative direction of solute movement. This wake behind the moving solute is more pronounced in case of mobile H2 and in solvents with weaker internal interactions. However, deviations from a spherical solvent cage shape do not influence solute-solvent radial distribution functions after averaging over all solvent cage orientations and hence do not change bar V_i. Overall, the applied methodology reproduces bar V_i and its variations reliably and the used bar V_i decompositions identify the underlying reasons behind observed bar V_i variations.

[Design and research progress of zero profile cervical Interbody cage].

PubMed

Zhu, Jia; Wang, Song; Liao, Zhenhua; Liu, Weiqiang

2017-02-01

Zero profile cervical interbody cage is an improvement of traditional fusion products and necessary supplement of emerging artificial intervertebral disc products. When applied in Anterior Cervical Decompression Fusion(ACDF), zero profile cervical interbody cage can preserve the advantages of traditional fusion and reduce the incidence of postoperative complications. Moreover, zero profile cervical interbody cage can be applied under the tabu symptoms of Artificial Cervical Disc Replacement(ACDR). This article summarizes zero profile interbody cage products that are commonly recognized and widely used in clinical practice in recent years, and reviews the progress of structure design and material research of zero profile cervical interbody cage products. Based on the latest clinical demands and research progress, this paper also discusses the future development directions of zero profile interbody cage.

Effects of Cage-Change Frequency and Bedding Volume on Mice and Their Microenvironment

PubMed Central

Rosenbaum, Matthew D; VandeWoude, Susan; Johnson, Thomas E

2009-01-01

The frequency at which mouse cages are changed has important implications for the animals, animal care personnel, and facility managers. The objective of this study was to determine how bedding volume and the interval between changes affect microenvironmental conditions, health, and behavior of mice housed in individually ventilated cages (IVC). A total of 15 cages (n = 5 cages per bedding volume) housing ICR female mice (n = 5 animals per cage) were monitored for 17 d. Parameters monitored included clinical evaluation of each animal, appearance of the cage, fecal corticosterone levels, bedding weight, and mouse mass. Atmospheric analysis was performed daily to determine intracage ammonia cage humidity and temperature on a daily basis. Mice were videotaped for 10 min on days 1, 8, and 15, and videos were analyzed for abnormal behaviors. On day 17, 1 mouse from each cage was euthanized, and bronchoalveolar lavage was performed. Statistical differences in parameters were most often noted between low- and high-volume bedding groups. Correlation between visual appearance and actual intracage environmental conditions and mouse health and behavior at specific time points indicated cages that appear dirty to most observers did not have measurably adverse effects on the animals for any of the many parameters evaluated in this study. This study demonstrated that a 2-wk interval between cage changes for ICR female mice housed in IVC caging (with approximately 90 air changes per hour) and aspen chip bedding did not significantly affect measures of animal well-being in this study. This lack of effect occurred despite the appearance of excessive soiling by the 2-wk time point. PMID:19930825

Coordinating subdomains of ferritin protein cages with catalysis and biomineralization viewed from the C4 cage axes.

PubMed

Theil, Elizabeth C; Turano, Paola; Ghini, Veronica; Allegrozzi, Marco; Bernacchioni, Caterina

2014-06-01

Integrated ferritin protein cage function is the reversible synthesis of protein-caged, solid Fe2O3·H2O minerals from Fe(2+) for metabolic iron concentrates and oxidant protection; biomineral order differs in different ferritin proteins. The conserved 432 geometric symmetry of ferritin protein cages parallels the subunit dimer, trimer, and tetramer interfaces, and coincides with function at several cage axes. Multiple subdomains distributed in the self-assembling ferritin nanocages have functional relationships to cage symmetry such as Fe(2+) transport though ion channels (threefold symmetry), biomineral nucleation/order (fourfold symmetry), and mineral dissolution (threefold symmetry) studied in ferritin variants. On the basis of the effects of natural or synthetic subunit dimer cross-links, cage subunit dimers (twofold symmetry) influence iron oxidation and mineral dissolution. 2Fe(2+)/O2 catalysis in ferritin occurs in single subunits, but with cooperativity (n = 3) that is possibly related to the structure/function of the ion channels, which are constructed from segments of three subunits. Here, we study 2Fe(2+) + O2 protein catalysis (diferric peroxo formation) and dissolution of ferritin Fe2O3·H2O biominerals in variants with altered subunit interfaces for trimers (ion channels), E130I, and external dimer surfaces (E88A) as controls, and altered tetramer subunit interfaces (L165I and H169F). The results extend observations on the functional importance of structure at ferritin protein twofold and threefold cage axes to show function at ferritin fourfold cage axes. Here, conserved amino acids facilitate dissolution of ferritin-protein-caged iron biominerals. Biological and nanotechnological uses of ferritin protein cage fourfold symmetry and solid-state mineral properties remain largely unexplored.

Coordinating Subdomains of Ferritin Protein Cages with Catalysis and Biomineralization viewed from the C4 Cage Axes

PubMed Central

Theil, Elizabeth C.; Turano, Paola; Ghini, Veronica; Allegrozzi, Marco; Bernacchioni, Caterina

2014-01-01

Integrated ferritin protein cage function is the reversible synthesis of protein-caged, solid Fe2O3•H2O minerals from Fe2+, for metabolic iron concentrates and oxidant protection; biomineral order varies in different ferritin proteins. The conserved 4, 3, 2 geometric symmetry of ferritin protein cages, parallels subunit dimer, trimer and tetramer interfaces, and coincides with function at several cage axes. Multiple subdomains distributed in the self- assembling ferritin nanocages have functional relationships to cage symmetry such as Fe2+ transport though ion channels (3-fold symmetry), biomineral nucleation/order (4-fold symmetry) and mineral dissolution (3-fold symmetry) studied in ferritin variants. Cage subunit dimers (2-fold symmetry) influence iron oxidation and mineral dissolution, based on effects of natural or synthetic subunit dimer crosslinks. 2Fe2+/O2 catalysis in ferritin occurs in single subunits, but with cooperativity (n=3) that is possibly related to the structure/function of the ion channels, which are constructed from segments of 3 subunits. Here, we study 2Fe2+ + O2 protein catalysis (diferric peroxo formation) and dissolution of ferritin Fe2O3•H2O biominerals in variants with altered subunit interfaces for trimers (ion channels), E130I, and external dimer surfaces (E88A) as controls, and altered tetramer subunit interfaces (L165I and H169F). The results extend observations on the functional importance of structure at ferritin protein 2-fold and 3-fold cage axes to show function at ferritin 4-fold cage axes. Here, conserved amino acids facilitate dissolution of ferritin protein-caged iron biominerals. Biological and nanotechnological uses of ferritin protein cage 4-fold symmetry and solid state mineral properties remain largely unexplored. PMID:24504941

Automatic analysis of altered gait in arylsulphatase A-deficient mice in the open field.

PubMed

Leroy, Toon; Stroobants, Stijn; Aerts, Jean-Marie; D'Hooge, Rudi; Berckmans, Daniel

2009-08-01

In current research with laboratory animals, observing their dynamic behavior or locomotion is a labor-intensive task. Automatic continuous monitoring can provide quantitative data on each animal's condition and coordination ability. The objective of the present work is to develop an automated mouse observation system integrated with a conventional open-field test for motor function evaluation. Data were acquired from 86 mice having a targeted disruption of the arylsulphatase A (ASA) gene and having lowered coordinated locomotion abilities as a symptom. The mice used were 36 heterozygotes (12 females) and 50 knockout mice (30 females) at the age of 6 months. The mice were placed one at a time into the test setup, which consisted of a Plexiglas cage (53x34.5x26 cm) and two fluorescent bulbs for proper illumination. The transparent cage allowed images to be captured from underneath the cage, so image information could be obtained about the dynamic variation of the positions of the limbs of the mice for gait reconstruction. Every mouse was recorded for 10 min. Background subtraction and color filtering were used to measure and calculate image features, which are variables that contain crucial information, such as the mouse's position, orientation, body outline, and possible locations for the mouse's paws. A set of heuristic rules was used to prune implausible paw features and label the remaining ones as front/hind and left/right. After we had pruned the implausible paw features, the paw features that were consistent over subsequent images were matched to footprints. Finally, from the measured footprint sequence, eight parameters were calculated in order to quantify the gait of the mouse. This automatic observation technique can be integrated with a regular open-field test, where the trajectory and motor function of a free-moving mouse are measured simultaneously.

Segmental kyphosis after cervical interbody fusion with stand-alone polyetheretherketone (PEEK) cages: a comparative study on 2 different PEEK cages.

PubMed

Kim, Chi Heon; Chung, Chun Kee; Jahng, Tae-Ahn; Park, Sung Bae; Sohn, Seil; Lee, Sungjoon

2015-02-01

Retrospective comparative study. Two polyetheretherketone (PEEK) cages of different designs were compared in terms of the postoperative segmental kyphosis after anterior cervical discectomy and fusion. Segmental kyphosis occasionally occurs after the use of a stand-alone cage for anterior cervical discectomy and fusion. Although PEEK material seems to have less risk of segmental kyphosis compared with other materials, the occurrence of segmental kyphosis for PEEK cages has been reported to be from 0% to 29%. There have been a few reports that addressed the issue of PEEK cage design. A total of 41 consecutive patients who underwent single-level anterior discectomy and fusion with a stand-alone cage were included. Either a round tube-type (Solis; 18 patients, S-group) or a trapezoidal tube-type (MC+; 23 patients, M-group) cage was used. The contact area between the cage and the vertebral body is larger in MC+ than in Solis, and anchoring pins were present in the Solis cage. The effect of the cage type on the segmental angle (SA) (lordosis vs. kyphosis) at postoperative month 24 was analyzed. Preoperatively, segmental lordosis was present in 12/18 S-group and 16/23 M-group patients (P=0.84). The SA was more lordotic than the preoperative angle in both groups just after surgery, with no difference between groups (P=0.39). At 24 months, segmental lordosis was observed in 9/18 S-group and 20/23 M-group patients (P=0.01). The patients in M-group were 7.83 times more likely than patients in S-group (P=0.04; odds ratio, 7.83; 95% confidence interval, 1.09-56.28) not to develop segmental kyphosis. The design of the PEEK cage used may influence the SA, and this association needs to be considered when using stand-alone PEEK cages.

The Impact of Cage Dimensions, Positioning, and Side of Approach in Extreme Lateral Interbody Fusion.

PubMed

Alimi, Marjan; Lang, Gernot; Navarro-Ramirez, Rodrigo; Perrech, Moritz; Berlin, Connor; Hofstetter, Christoph P; Moriguchi, Yu; Elowitz, Eric; Härtl, Roger

2018-02-01

This is a retrospective single-center study. The aim of the study was to evaluate the impact of cage characteristics and position toward clinical and radiographic outcome measures in patients undergoing extreme lateral interbody fusion (ELIF). ELIF is utilized for indirect decompression and minimally invasive surgical treatment for various degenerative spinal disorders. However, evidence regarding the influence of cage characteristics in patient outcome is minimal. Patients undergoing ELIF between 2007 and 2011 were included in a retrospective study. Demographic and perioperative data, as well as cage characteristics and side of approach were extracted. Radiographic parameters including lumbar lordosis, foraminal height, and disc height as well as clinical outcome parameters (Oswestry Disability Index and Visual Analog Scale) were measured preoperatively, postoperatively, and at the latest follow-up examination. Cage dimensions, in situ position, and type were correlated with radiographic and clinical outcome parameters. In total, 84 patients with a total of 145 functional spinal units were analyzed. At the last follow-up of 17.7 months, radiographic and clinical outcome measures revealed significant improvement compared with before surgery with both, 18 and 22 mm cage anterior-posterior diameter subgroups (P≤0.05). Among cage characteristics, 22 mm cages presented superior restoration of foraminal and disc heights compared with 18 mm cages (P≤0.05). Neither position of the cage (anterior vs. posterior), nor the type (parallel vs. lordotic) had a significant impact on restoration of foraminal height and lumbar lordosis. Moreover, the side of surgical approach did not influence the amount of foraminal height increase. Cage anterior-posterior diameter is the determining factor in restoration of foraminal height in ELIF. Cage height, type, positioning, and side of approach do not have a determining role in radiographic outcome in the present study. Sustainable foraminal height restoration is achieved by implantation of wider cages. Level 3.

Determination of the equation of state of asymmetric nuclear matter

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

Tsang, Manyee Betty

A new Time Projection Chamber (TPC), called the SπRIT (SAMURAI pion Reconstruction Ion Tracker) TPC was constructed and used successfully in two experiments with the SAMURAI spectrometer at RIKEN, Japan to study the equation of state of neutron rich matter. As a result of the project, the SπRIT collaboration, an international collaboration consisting of groups from US, Japan, Korea, Poland, China and Germany, has been formed to pursue the science opportunities provided by the SπRIT TPC. After completion of the TPC and the two experiments, the collaboration continues to develop the software to analyze the SπRIT experiments and extract constraintsmore » of symmetry energy at supra-saturation densities. Over 250 TB of data have been obtained in the last SπRIT TPC experimental campaign. Construction of the TPC provided opportunities for the scientists to develop new designs for the light-weight and thin-walled field cage for the large pad plane and for the gating grid. Two PhD students (1 US and 1 Korea) graduated in 2016 based on their research on the TPC. At least four more doctoral theses (2 US, 1 Japan and 1 Korea) based on physics from the SπRIT experiments are expected.« less

Effect of 2 Bedding Materials on Ammonia Levels in Individually Ventilated Cages

PubMed Central

Koontz, Jason M; Kumsher, David M; III, Richard Kelly; Stallings, Jonathan D

2016-01-01

This study sought to identify an optimal rodent bedding and cage-change interval to establish standard procedures for the IVC in our rodent vivarium. Disposable cages were prefilled with either corncob or α-cellulose bedding and were used to house 2 adult Sprague–Dawley rats (experimental condition) or contained no animals (control). Rats were observed and intracage ammonia levels measured daily for 21 d. Intracage ammonia accumulation became significant by day 8 in experimental cages containing α-cellulose bedding, whereas experimental cages containing corncob bedding did not reach detectable levels of ammonia until day 14. In all 3 experimental cages containing α-cellulose, ammonia exceeded 100 ppm (our maximum acceptable limit) by day 11. Two experimental corncob cages required changing at days 16 and 17, whereas the remaining cage containing corncob bedding lasted the entire 21 d without reaching the 100-ppm ammonia threshold. These data suggests that corncob bedding provides nearly twice the service life of α-cellulose bedding in the IVC system. PMID:26817976

Effect of 2 Bedding Materials on Ammonia Levels in Individually Ventilated Cages.

PubMed

Koontz, Jason M; Kumsher, David M; Kelly, Richard; Stallings, Jonathan D

2016-01-01

This study sought to identify an optimal rodent bedding and cage-change interval to establish standard procedures for the IVC in our rodent vivarium. Disposable cages were prefilled with either corncob or α-cellulose bedding and were used to house 2 adult Sprague-Dawley rats (experimental condition) or contained no animals (control). Rats were observed and intracage ammonia levels measured daily for 21 d. Intracage ammonia accumulation became significant by day 8 in experimental cages containing α-cellulose bedding, whereas experimental cages containing corncob bedding did not reach detectable levels of ammonia until day 14. In all 3 experimental cages containing α-cellulose, ammonia exceeded 100 ppm (our maximum acceptable limit) by day 11. Two experimental corncob cages required changing at days 16 and 17, whereas the remaining cage containing corncob bedding lasted the entire 21 d without reaching the 100-ppm ammonia threshold. These data suggests that corncob bedding provides nearly twice the service life of α-cellulose bedding in the IVC system.

A Pseudo-Atomic Model of the COPII Cage Obtained from CryoEM and Mass Spectrometry Analyses

PubMed Central

Noble, Alex J.; Zhang, Qian; O’Donnell, Jason; Hariri, Hanaa; Bhattacharya, Nilakshee; Marshall, Alan G.

2012-01-01

COPII vesicles transport proteins from the ER to the Golgi apparatus. Previous cryoEM structures of the COPII cage lacked the resolution necessary to determine the residues of Sec13 and Sec31 that mediate assembly and flexibility of the COPII cage. Here we present a 12Å-resolution structure of the COPII cage, where the tertiary structure of Sec13 and Sec31 is clearly identifiable. We employ this structure and a homology model of the Sec13-Sec31 complex to create a reliable pseudo-atomic model of the COPII cage. We combined this model with hydrogen/deuterium exchange mass spectrometry analysis to characterize four distinct contact regions at the vertices of the COPII cage. Furthermore, we found that the 2-fold symmetry of the Sec31 dimeric region of Sec13-31 is broken on cage formation, and that the resulting hinge is essential to form the proper edge geometry in COPII cages. PMID:23262493

A library of protein cage architectures as nanomaterials.

PubMed

Flenniken, M L; Uchida, M; Liepold, L O; Kang, S; Young, M J; Douglas, T

2009-01-01

Virus capsids and other structurally related cage-like proteins such as ferritins, dps, and heat shock proteins have three distinct surfaces (inside, outside, interface) that can be exploited to generate nanomaterials with multiple functionality by design. Protein cages are biological in origin and each cage exhibits extremely homogeneous size distribution. This homogeneity can be used to attain a high degree of homogeneity of the templated material and its associated property. A series of protein cages exhibiting diversity in size, functionality, and chemical and thermal stabilities can be utilized for materials synthesis under a variety of conditions. Since synthetic approaches to materials science often use harsh temperature and pH, it is an advantage to utilize protein cages from extreme environments. In this chapter, we review recent studies on discovering novel protein cages from harsh natural environments such as the acidic thermal hot springs at Yellowstone National Park (YNP) and on utilizing protein cages as nano-scale platforms for developing nanomaterials with wide range of applications from electronics to biomedicine.

Aedes albopictus (Skuse) males in laboratory and semi-field cages: release ratios and mating competitiveness.

PubMed

Madakacherry, Odessa; Lees, Rosemary Susan; Gilles, Jeremie Roger Lionel

2014-04-01

To control the container-breeding mosquito and major vector of dengue and chikungunya Aedes albopictus, the sterile insect technique (SIT) is proposed as a component of integrated vector management programs in endemic areas. For the technique to be successful, released males, sterilized with 35 Gy of ionizing radiation during the pupal stage, must be able to compete for mating opportunities with wild counterparts and successfully copulate with wild females to induce sterility in the population. Any reduction in competitiveness can be compensated for by increasing the ratio of released sterile to wild males, a ratio which must be optimized for effectiveness and efficiency. Fruit fly SIT programs use field enclosures to test the competitiveness of sterile males to monitor the quality of the colony and adjust release ratios. This is laborious and time consuming, and for mosquito programs it would be advantageous if similarly useful results could be obtained by smaller scale laboratory tests, conducted on a more regular basis. In the present study we compared the competitiveness, as measured by hatching rate of resulting egg batches, of irradiated males measured in small and large laboratory cages and semi-field enclosures in a greenhouse setting, when competing in a 1:1, 3:1, and 5:1 ratio with fertile males. The sterile males were found to be equally competitive when compared to unirradiated counterparts, and a 5:1 ratio was sufficient to reduce, but not eliminate, the fertility of the female populations, irrespective of cage size. Variability in hatch rate in eggs laid by individual females and so-called indeterminate matings, when we could not be certain whether a female had mated a fertile or a sterile male, could be investigated by closer investigation of mating status and the frequency of multiple matings in Ae. albopictus. The laboratory results are encouraging for the effectiveness of the SIT using irradiated males of this species, and we support further assessment in the field. Copyright © 2013 International Atomic Energy Agency 2013. Published by Elsevier B.V. All rights reserved.

The Evolution of the Cup-Cage Technique for Major Acetabular Defects: Full and Half Cup-Cage Reconstruction.

PubMed

Sculco, Peter K; Ledford, Cameron K; Hanssen, Arlen D; Abdel, Matthew P; Lewallen, David G

2017-07-05

Complex acetabular reconstruction for major bone loss can require advanced methods such as the use of a cup-cage construct. The purpose of this study was to review outcomes after the initial development of the cup-cage technique and the subsequent evolution to the use of a half cup-cage construct. We performed a retrospective, single-center review of 57 patients treated with cup-cage reconstruction for major acetabular bone loss. All patients had major acetabular defects graded as Paprosky Type 2B through 3B, with 34 (60%) having an associated pelvic discontinuity. Thirty patients received a full cup-cage construct and 27, a half cup-cage construct. The mean follow-up was 5 years. Both the full and half cup-cage cohorts demonstrated significantly improved Harris hip score (HHS) values, from 36 to 72 at a minimum of 2 years of follow-up (p < 0.05). Early construct migration occurred in 4 patients, with stabilization prior to 2-year follow-up in all but 1 patient. Incomplete, zone-3, nonprogressive acetabular radiolucencies were observed in 2 (7%) of the full cup-cage constructs and 6 (22%) of the half cup-cage constructs. One patient with a full cup-cage construct underwent re-revision of the acetabular component for progressive migration and aseptic loosening. Short-term survivorship free from re-revision for any cause or reoperation was 89% (83% and 96% for full and half cup-cage cohorts, respectively). Both full and half cup-cage constructs demonstrated successful clinical outcomes and survivorship in the treatment of major acetabular defects and pelvic discontinuity. Each method is utilized on the basis of individual intraoperative findings, including the extent and pattern of bone loss, the quality and location of host bone remaining after preparation, and the presence of pelvic discontinuity. Longer-term follow-up is required to understand the durability of these constructs in treating major acetabular defects and pelvic discontinuity. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Role of Tryptophan Side Chain Dynamics on the Trp-Cage Mini-Protein Folding Studied by Molecular Dynamics Simulations

PubMed Central

Kannan, Srinivasaraghavan; Zacharias, Martin

2014-01-01

The 20 residue Trp-cage mini-protein is one of smallest proteins that adopt a stable folded structure containing also well-defined secondary structure elements. The hydrophobic core is arranged around a single central Trp residue. Despite several experimental and simulation studies the detailed folding mechanism of the Trp-cage protein is still not completely understood. Starting from fully extended as well as from partially folded Trp-cage structures a series of molecular dynamics simulations in explicit solvent and using four different force fields was performed. All simulations resulted in rapid collapse of the protein to on average relatively compact states. The simulations indicate a significant dependence of the speed of folding to near-native states on the side chain rotamer state of the central Trp residue. Whereas the majority of intermediate start structures with the central Trp side chain in a near-native rotameric state folded successfully within less than 100 ns only a fraction of start structures reached near-native folded states with an initially non-native Trp side chain rotamer state. Weak restraining of the Trp side chain dihedral angles to the state in the folded protein resulted in significant acceleration of the folding both starting from fully extended or intermediate conformations. The results indicate that the side chain conformation of the central Trp residue can create a significant barrier for controlling transitions to a near native folded structure. Similar mechanisms might be of importance for the folding of other protein structures. PMID:24563686

Caged compounds: tools for illuminating neuronal responses and connections.

PubMed

Nerbonne, J M

1996-06-01

A number of new 'caged' intracellular second messengers and neurotransmitters have been developed using the photolabile o-nitrobenzyl group. This chemistry has also recently been exploited in novel ways, including the development of caged enzyme substrates and caged proteins. Although caged compounds continue to be used primarily for mechanistic (kinetic) studies of processes mediated by transmitters or second messengers, the spatial resolution afforded by the use of light to effect changes in transmitter concentrations has now been clearly demonstrated. The increased availability of caged compounds and of the technologies required to exploit them provides neurobiologists with powerful tools for probing neuronal response properties and connectivity patterns.

Caged Molecular Glues as Photoactivatable Tags for Nuclear Translocation of Guests in Living Cells.

PubMed

Arisaka, Akio; Mogaki, Rina; Okuro, Kou; Aida, Takuzo

2018-02-21

We developed dendritic caged molecular glues ( Caged Glue-R) as tags for nucleus-targeted drug delivery, whose multiple guanidinium ion (Gu + ) pendants are protected by an anionic photocleavable unit (butyrate-substituted nitroveratryloxycarbonyl; BA NVOC). Negatively charged Caged Glue-R hardly binds to anionic biomolecules because of their electrostatic repulsion. However, upon exposure of Caged Glue-R to UV light or near-infrared (NIR) light, the BA NVOC groups of Caged Glue-R are rapidly detached to yield an uncaged molecular glue ( Uncaged Glue-R) that carries multiple Gu + pendants. Because Gu + forms a salt bridge with PO 4 - , Uncaged Glue-R tightly adheres to anionic biomolecules such as DNA and phospholipids in cell membranes by a multivalent salt-bridge formation. When tagged with Caged Glue-R, guests can be taken up into living cells via endocytosis and hide in endosomes. However, when the Caged Glue-R tag is photochemically uncaged to form Uncaged Glue-R, the guests escape from the endosome and migrate into the cytoplasm followed by the cell nucleus. We demonstrated that quantum dots (QDs) tagged with Caged Glue-R can be delivered efficiently to cell nuclei eventually by irradiation with light.

Application of the independent molecule model to elucidate the dynamics of structure I methane hydrate: a third report.

PubMed

Yoshioki, Shuzo

2009-01-01

Two new model systems of methane hydrate, larger than the previous systems, are constructed. One consists of 63 small and large cages with a small cage at the centre. The other has 65 small and large cages with a large cage at the centre. Three different H-bonding network patterns between water are formed, and three random orientations of methane in each cage are chosen. Using the surface water fixed method, we obtained the energy minimum conformations, fitted to the X-ray crystallographic structure. With normal mode analysis, we calculated frequencies of 2915.1 cm(-1) for a small cage, and 2911.0 cm(-1) for a large cage. These frequencies are a little nearer to the Raman spectra than were previous model systems. Treating three force constants of anharmonic potential energy and the strength of H-bonding between methane and water as four parameters, we obtained frequencies of 2913.6 cm(-1) for a small cage, a little lower than the Raman, and 2906.6 cm(-1) for a large cage, a little higher than the Raman. The calculations thus almost reach the Raman spectra.

Virucidal effects of rodent cage-cleaning practices on the viability of adenovirus vectors.

PubMed

Porter, Jacqueline D; Lyons, Russette M

2002-09-01

Human adenoviruses and adenoviral vectors are classified as Risk Group 2 agents and require BSL2 containment and practices. An additional consideration in using adenoviruses and viral vectors in laboratory animal studies is the possible transmission of these agents to other animals and/or personnel as a result of viral shedding in animal urine and feces. When handling BSL2 agents, cage-wash staff are required to wear appropriate personnel protective equipment, including scrubs, Tyvek suit, hair covering, dust mask, shoes covers, and gloves. Current decontamination procedures are to bag and autoclave soiled rodent cages containing bedding prior to washing in the cage washer to prevent possible adenoviral transmission. However, the practice of autoclaving softens the polycarbonate-based rodent cages, allowing damaging agents or conditions to affect the integrity of the plastic and degrade the cages. The objective of this study was to determine whether current rodent cage-cleaning practices produced virucidal effects for use in lieu of or prior to autoclaving the cages. We found that heating an Av3GFP vector in a test tube to a temperature of 74 degrees C (165 degrees F) for 6 min conditions equivalent to those of the cage washer resulted in greater than an 11-log reduction in infectivity of the vector as evaluated by its cytopathic effect on cells. The combination of heating and a liquid, phosphate-free alkaline detergent produced the same reduction in vector infectivity. However, common cage-cleaning solutions alone possessed no virucidal activity. The high temperatures used in cage-washing procedures alone or in combination with a cleaning solution reduced or eliminated the risk of transmission from viral shedding through urine and feces even at vector concentrations far greater than would ever be expected to be present. Autoclaving cages diminishes the stability and integrity of the polycarbonate cages without providing a further reduction in the risk of virus or vector transmission. On the basis of results from this study, new cage-wash recommendations include dumping the contaminated bedding into a HEPA-filtered waste disposal system and autoclaving the bags of bedding before disposal, then cleaning the cages in the rack washer at wash temperatures of 74 degrees C (165 F) and rinse temperatures of 82 degrees C (180 F).

[Detection of alcoholism in the medical office: applicability of the CAGE questionnaire by the practicing physician. Group of Medical Practitioners PMU].

PubMed

Perdrix, A; Decrey, H; Pécoud, A; Burnand, B; Yersin, B

1995-09-23

The general practitioner (GP) plays a very important role in early detection of alcoholism. Clinical evaluation is often the only method used, although it has been suggested that any systematic patient history should include the CAGE test. We compare the effectiveness of these two approaches and attempt to determine the applicability of the CAGE test in a general practitioner's usual practice. 12 GPs took part in this study during 6 months. They looked for possible alcohol abuse in each new patient by a standard patient history and clinical examination. Patients were randomized into 2 groups, one of which was given the CAGE test and the other not. For each patient in the CAGE group the applicability of the test was quantified by the GP. 416 patients were included; 214 were randomized into the "CAGE group" and 202 into the control group. On a clinical basis, 15 patients in the control group and 16 in the "CAGE group" (14 men, 2 women) were suspected of alcohol abuse. The CAGE test was positive in 15 patients (7%); among these, 6 were not suspect on a clinical basis. In patients aged 18-34, the detection rate of alcohol-related problems more than doubled when the CAGE test was used. The age of the patients influenced performance of the CAGE test and clinical evaluation. Only 2% of women had a positive CAGE test. Administration of the CAGE test was considered easy in 112 patients and average to difficult in 50, while the test was inapplicable with 52 patients. The latter proportion was higher than that observed in institutions (hospitals, outpatient departments) of the same region. Applicability was influenced neither by the sex nor the age of the patients, but varied greatly according to the physician (from 38% to 100%). The CAGE test increases the number of patients detected with alcohol problems by 37% and seems to be especially useful when administered to young people. The number of women with alcohol problems is probably underestimated by both clinical evaluation and the CAGE test. Furthermore, physicians in private practice are more reluctant to use the CAGE test systematically than those in a public institution.

Indirect Lightning Safety Assessment Methodology

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

Ong, M M; Perkins, M P; Brown, C G

2009-04-24

Lightning is a safety hazard for high-explosives (HE) and their detonators. In the However, the current flowing from the strike point through the rebar of the building The methodology for estimating the risk from indirect lighting effects will be presented. It has two parts: a method to determine the likelihood of a detonation given a lightning strike, and an approach for estimating the likelihood of a strike. The results of these two parts produce an overall probability of a detonation. The probability calculations are complex for five reasons: (1) lightning strikes are stochastic and relatively rare, (2) the quality ofmore » the Faraday cage varies from one facility to the next, (3) RF coupling is inherently a complex subject, (4) performance data for abnormally stressed detonators is scarce, and (5) the arc plasma physics is not well understood. Therefore, a rigorous mathematical analysis would be too complex. Instead, our methodology takes a more practical approach combining rigorous mathematical calculations where possible with empirical data when necessary. Where there is uncertainty, we compensate with conservative approximations. The goal is to determine a conservative estimate of the odds of a detonation. In Section 2, the methodology will be explained. This report will discuss topics at a high-level. The reasons for selecting an approach will be justified. For those interested in technical details, references will be provided. In Section 3, a simple hypothetical example will be given to reinforce the concepts. While the methodology will touch on all the items shown in Figure 1, the focus of this report is the indirect effect, i.e., determining the odds of a detonation from given EM fields. Professor Martin Uman from the University of Florida has been characterizing and defining extreme lightning strikes. Using Professor Uman's research, Dr. Kimball Merewether at Sandia National Laboratory in Albuquerque calculated the EM fields inside a Faraday-cage type facility, when the facility is struck by lightning. In the following examples we will use Dr. Merewether's calculations from a poor quality Faraday cage as the input for the RF coupling analysis. coupling of radio frequency (RF) energy to explosive components is an indirect effect of currents [1]. If HE is adequately separated from the walls of the facility that is struck by disassembled have been turned into Faraday-cage structures to protect against lightning is initiation of the HE. last couple of decades, DOE facilities where HE is manufactured, assembled, stored or lightning. The most sensitive component is typically a detonator, and the safety concern lightning, electrons discharged from the clouds should not reach the HE components. radio receiver, the metal cable of a detonator can extract energy from the EM fields. This to the earth will create electromagnetic (EM) fields in the facility. Like an antenna in a« less

Quadratic stark effect in the fullerene C60 at low symmetry orientation in the field

NASA Astrophysics Data System (ADS)

Tuchin, A. V.; Bityutskaya, L. A.; Bormontov, E. N.

2014-08-01

Results of numeric simulation of the influence of the electric field E = 0 - 1 V/Å on the electronic structure of the neutral fullerene C60 taking into account orientational deformation of its carbon cage at arbitrary orientations in the electric field including low symmetry orientations are presented. Splitting of the frontier t 1 u - and h u -levels of the molecule due to the quadratic Stark effect has been investigated. Dependencies of the effective electron work function and the energy gap between the lowest unoccupied and highest occupied molecular orbitals on the strengths of the electric field have been determined.

[H2O ortho-para spin conversion in aqueous solutions as a quantum factor of Konovalov paradox].

PubMed

Pershin, S M

2014-01-01

Recently academician Konovalov and co-workers observed an increase in electroconductivity and biological activity simultaneously with diffusion slowing (or nanoobject diameter increasing) and extremes of other parameters (ζ-potential, surface tension, pH, optical activity) in low concentration aqueous solutions. This phenomenon completely disappeared when samples were shielded against external electromagnetic fields by a Faraday cage. A conventional theory of water and water solutions couldn't explain "Konovalov paradox" observed in numerous experiments (representative sampling about 60 samples and 7 parameters). The new approach was suggested to describe the physics of water and explain "Konovalov paradox". The proposed concept takes into account the quantum differences of ortho-para spin isomers of H2O in bulk water (rotational spin-selectivity upon hydration and spontaneous formation of ice-like structures, quantum beats and spin conversion induced in the presence of a resonant electromagnetic radiation). A size-dependent self-assembly of amorphous complexes of H2O molecules more than 275 leading to the ice Ih structure observed in the previous experiments supports this concept.

The illusive sound of a Bundengan string

NASA Astrophysics Data System (ADS)

Parikesit, Gea O. F.; Kusumaningtyas, Indraswari

2017-09-01

The acoustics of a vibrating string is frequently used as a simple example of how physics can be applied in the field of art. In this paper we describe a simple experiment and analysis using a clipped string. This experiment can generate scientific curiosity among students because the sound generated by the string seem surprising to our senses. The first surprise comes from the gong-like sounds produced by the string, which we usually associate with metallic instruments rather than string instruments. The second surprise comes from the fact that when we shift the clip we perceive an increase of pitch, even though the measured value of the frequency with the maximum amplitude is actually decreased. We use high-speed video recording as well as audio spectral analysis to elucidate the physics behind these two surprises. A set of student activities is prepared to help them follow up their curiosity. Students can make their own clipped string, which is found in Indonesia in an instrument called Bundengan, by setting up their own prepared piano as invented by John Cage.

A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage.

PubMed

Yang, Z; Chen, H; Yu, T; Li, B

2016-08-01

The high-precision ball bearing is fundamental to the performance of complex mechanical systems. As the speed increases, the cage behavior becomes a key factor in influencing the bearing performance, especially life and reliability. This paper develops a high-precision instrument for analyzing nonlinear dynamic behavior of the bearing cage. The trajectory of the rotational center and non-repetitive run-out (NRRO) of the cage are used to evaluate the instability of cage motion. This instrument applied an aerostatic spindle to support and spin test the bearing to decrease the influence of system error. Then, a high-speed camera is used to capture images when the bearing works at high speeds. A 3D trajectory tracking software tema Motion is used to track the spot which marked the cage surface. Finally, by developing the matlab program, a Lissajous' figure was used to evaluate the nonlinear dynamic behavior of the cage with different speeds. The trajectory of rotational center and NRRO of the cage with various speeds are analyzed. The results can be used to predict the initial failure and optimize cage structural parameters. In addition, the repeatability precision of instrument is also validated. In the future, the motorized spindle will be applied to increase testing speed and image processing algorithms will be developed to analyze the trajectory of the cage.

A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage

NASA Astrophysics Data System (ADS)

Yang, Z.; Chen, H.; Yu, T.; Li, B.

2016-08-01

The high-precision ball bearing is fundamental to the performance of complex mechanical systems. As the speed increases, the cage behavior becomes a key factor in influencing the bearing performance, especially life and reliability. This paper develops a high-precision instrument for analyzing nonlinear dynamic behavior of the bearing cage. The trajectory of the rotational center and non-repetitive run-out (NRRO) of the cage are used to evaluate the instability of cage motion. This instrument applied an aerostatic spindle to support and spin test the bearing to decrease the influence of system error. Then, a high-speed camera is used to capture images when the bearing works at high speeds. A 3D trajectory tracking software tema Motion is used to track the spot which marked the cage surface. Finally, by developing the matlab program, a Lissajous' figure was used to evaluate the nonlinear dynamic behavior of the cage with different speeds. The trajectory of rotational center and NRRO of the cage with various speeds are analyzed. The results can be used to predict the initial failure and optimize cage structural parameters. In addition, the repeatability precision of instrument is also validated. In the future, the motorized spindle will be applied to increase testing speed and image processing algorithms will be developed to analyze the trajectory of the cage.

Biomechanical Evaluation of a Novel Apatite-Wollastonite Ceramic Cage Design for Lumbar Interbody Fusion: A Finite Element Model Study

PubMed Central

Şenköylü, Alpaslan; Aktaş, Erdem; Sarıkaya, Baran; Sipahioğlu, Serkan; Gürbüz, Rıza; Timuçin, Muharrem

2018-01-01

Objectives Cage design and material properties play a crucial role in the long-term results, since interbody fusions using intervertebral cages have become one of the basic procedures in spinal surgery. Our aim is to design a novel Apatite-Wollastonite interbody fusion cage and evaluate its biomechanical behavior in silico in a segmental spinal model. Materials and Methods Mechanical properties for the Apatite-Wollastonite bioceramic cages were obtained by fitting finite element results to the experimental compression behavior of a cage prototype. The prototype was made from hydroxyapatite, pseudowollastonite, and frit by sintering. The elastic modulus of the material was found to be 32 GPa. Three intact lumbar vertebral segments were modelled with the ANSYS 12.0.1 software and this model was modified to simulate a Posterior Lumbar Interbody Fusion. Four cage designs in different geometries were analyzed in silico under axial loading, flexion, extension, and lateral bending. Results The K2 design had the best overall biomechanical performance for the loads considered. Maximum cage stress recorded was 36.7 MPa in compression after a flexion load, which was within the biomechanical limits of the cage. Conclusion Biomechanical analyses suggest that K2 bioceramic cage is an optimal design and reveals essential material properties for a stable interbody fusion. PMID:29581974

A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage

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

Yang, Z., E-mail: zhaohui@nwpu.edu.cn; Yu, T.; Chen, H.

2016-08-15

The high-precision ball bearing is fundamental to the performance of complex mechanical systems. As the speed increases, the cage behavior becomes a key factor in influencing the bearing performance, especially life and reliability. This paper develops a high-precision instrument for analyzing nonlinear dynamic behavior of the bearing cage. The trajectory of the rotational center and non-repetitive run-out (NRRO) of the cage are used to evaluate the instability of cage motion. This instrument applied an aerostatic spindle to support and spin test the bearing to decrease the influence of system error. Then, a high-speed camera is used to capture images whenmore » the bearing works at high speeds. A 3D trajectory tracking software TEMA Motion is used to track the spot which marked the cage surface. Finally, by developing the MATLAB program, a Lissajous’ figure was used to evaluate the nonlinear dynamic behavior of the cage with different speeds. The trajectory of rotational center and NRRO of the cage with various speeds are analyzed. The results can be used to predict the initial failure and optimize cage structural parameters. In addition, the repeatability precision of instrument is also validated. In the future, the motorized spindle will be applied to increase testing speed and image processing algorithms will be developed to analyze the trajectory of the cage.« less

Chronic social isolation and chronic variable stress during early development induce later elevated ethanol intake in adult C57BL/6J mice.

PubMed

Lopez, Marcelo F; Doremus-Fitzwater, Tamara L; Becker, Howard C

2011-06-01

Experience with stress situations during early development can have long-lasting effects on stress- and anxiety-related behaviors. Importantly, this can also favor drug self-administration. These studies examined the effects of chronic social isolation and/or variable stress experiences during early development on subsequent voluntary ethanol intake in adult male and female C57BL/6J mice. The experiments were conducted to evaluate the effect of chronic isolation between weaning and adulthood (Experiment 1), chronic isolation during adulthood (Experiment 2), and chronic variable stress (CVS) alone or in combination with chronic social isolation between weaning and adulthood (Experiment 3) on subsequent voluntary ethanol intake. Mice were born in our facility and were separated into two housing conditions: isolate housed (one mouse/cage) or group housed (four mice/cage) according to sex. Separate groups were isolated for 40 days starting either at time of weaning postnatal day 21 (PD 21) (early isolation, Experiments 1 and 3) or at adulthood (PD 60: late isolation, Experiment 2). The effects of housing condition on subsequent ethanol intake were assessed starting at around PD 65 in Experiments 1 and 3 or PD 105 days in Experiment 2. In Experiment 3, starting at PD 32, isolate-housed and group-housed mice were either subjected to CVS or left undisturbed. CVS groups experienced random presentations of mild stressors for 14 days, including exposure to an unfamiliar open field, restraint, physical shaking, and forced swim, among others. All mice were tested for ethanol intake for 14 days using a two-bottle choice (ethanol 15% vol/vol vs. water) for a 2-h limited access procedure. Early social isolation resulted in greater ethanol intake compared with the corresponding group-housed mice (Experiment 1). In contrast, social isolation during adulthood (late isolation) did not increase subsequent ethanol intake compared with the corresponding group-housed mice (Experiment 2). For mice that did not experience CVS, early social isolation resulted in greater ethanol intake compared with group-housed mice (Experiment 3). CVS subsequently resulted in a significant increase in ethanol intake in group-housed mice, but CVS failed to further increase ethanol intake in mice that experienced chronic social isolation early in life (Experiment 3). Overall, female mice consumed more ethanol than males, whether isolated (early or late) or group housed. These results indicate that early but not late social isolation can subsequently influence ethanol consumption in C57BL/6J mice. Thus, the developmental timing of chronic social isolation appears to be an important factor in defining later effects on ethanol self-administration behavior. In addition, experience with CVS early in life results in elevated ethanol intake later in adulthood. Taken together, these results emphasize the important role of early stress experiences that modulate later voluntary ethanol intake during adulthood. Copyright © 2011 Elsevier Inc. All rights reserved.

Porous titanium-6 aluminum-4 vanadium cage has better osseointegration and less micromotion than a poly-ether-ether-ketone cage in sheep vertebral fusion.

PubMed

Wu, Su-Hua; Li, Yi; Zhang, Yong-Quan; Li, Xiao-Kang; Yuan, Chao-Fan; Hao, Yu-Lin; Zhang, Zhi-Yong; Guo, Zheng

2013-12-01

Interbody fusion cages made of poly-ether-ether-ketone (PEEK) have been widely used in clinics for spinal disorders treatment; however, they do not integrate well with surrounding bone tissue. Ti-6Al-4V (Ti) has demonstrated greater osteoconductivity than PEEK, but the traditional Ti cage is generally limited by its much greater elastic modulus (110 GPa) than natural bone (0.05-30 GPa). In this study, we developed a porous Ti cage using electron beam melting (EBM) technique to reduce its elastic modulus and compared its spinal fusion efficacy with a PEEK cage in a preclinical sheep anterior cervical fusion model. A porous Ti cage possesses a fully interconnected porous structure (porosity: 68 ± 5.3%; pore size: 710 ± 42 μm) and a similar Young's modulus as natural bone (2.5 ± 0.2 GPa). When implanted in vivo, the porous Ti cage promoted fast bone ingrowth, achieving similar bone volume fraction at 6 months as the PEEK cage without autograft transplantation. Moreover, it promoted better osteointegration with higher degree (2-10x) of bone-material binding, demonstrated by histomorphometrical analysis, and significantly higher mechanical stability (P < 0.01), shown by biomechanical testing. The porous Ti cage fabricated by EBM could achieve fast bone ingrowth. In addition, it had better osseointegration and superior mechanical stability than the conventional PEEK cage, demonstrating great potential for clinical application. © 2013 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.

Influence of the ionic liquid [C4mpy][Tf2N] on the structure of the miniprotein Trp-cage.

PubMed

Baker, Joseph L; Furbish, Jeffrey; Lindberg, Gerrick E

2015-11-01

We examine the effect of the ionic liquid [C4mpy][Tf2N] on the structure of the miniprotein Trp-cage and contrast these results with the behavior of Trp-cage in water. We find the ionic liquid has a dramatic effect on Trp-cage, though many similarities with aqueous Trp-cage are observed. We assess Trp-cage folding by monitoring root mean square deviation from the crystallographic structure, radius of gyration, proline cis/trans isomerization state, protein secondary structure, amino acid contact formation and distance, and native and non-native contact formation. Starting from an unfolded configuration, Trp-cage folds in water at 298 K in less than 500 ns of simulation, but has very little mobility in the ionic liquid at the same temperature, which can be ascribed to the higher ionic liquid viscosity. At 365 K, the mobility of the ionic liquid is increased and initial stages of Trp-cage folding are observed, however Trp-cage does not reach the native folded state in 2 μs of simulation in the ionic liquid. Therefore, in addition to conventional molecular dynamics, we also employ scaled molecular dynamics to expedite sampling, and we demonstrate that Trp-cage in the ionic liquid does closely approach the aqueous folded state. Interestingly, while the reduced mobility of the ionic liquid is found to restrict Trp-cage motion, the ionic liquid does facilitate proline cis/trans isomerization events that are not seen in our aqueous simulations. Copyright © 2015 Elsevier Inc. All rights reserved.

Topiramate moderately reduces the motivation to consume alcohol and has a marked antidepressant effect in rats.

PubMed

Hargreaves, Garth A; McGregor, Iain S

2007-11-01

In recent human studies, the anticonvulsant drug topiramate (TPM) has shown efficacy in treating alcohol craving and mood disorders. However, preclinical evidence supporting such effects is surprisingly sparse. Three experiments were conducted here to assess possible anticraving and antidepressant effects of TPM using animal models. In Experiment 1, rats were given 23 weeks ad libitum access to food, water, and either beer (4.44% ethanol v/v) or "near-beer" (a calorie-matched nonalcoholic beer, 0.44% ethanol) in their home cages. They were then restricted to daily 1 hour operant sessions in which they licked for water and either beer or near-beer under a progressive ratio schedule of reinforcement in a lickometer apparatus. The acute effects of TPM on the motivation to consume beer or near-beer were then assessed. The effects of naloxone were also assessed (as a positive control) after TPM testing. In Experiment 2, rats were given 11 weeks of ad libitum home-cage access to food, water, and beer. They then received repeated daily injections of TPM and effects on beer consumption under ad libitum home cage access conditions were monitored. In Experiment 3, the effects of TPM were assessed in the modified Porsolt forced swim test, emergence test, and elevated plus-maze (EPM) using alcohol naïve rats. Topiramate (10, 20, and 40 mg/kg) significantly reduced the motivation to lick for beer, although the maximal effect was moderate in comparison with naloxone (10 mg/kg). However, naloxone, unlike TPM, also reduced responding for near-beer suggesting an alcohol-specific effect of TPM. In Experiment 2, TPM (40 and 80 mg/kg) tended to transiently reduce alcohol consumption in the home cage under ad libitum access but this effect disappeared with repeated administration of the drug. TPM (10 to 80 mg/kg, given twice over 4 hours before test) produced a robust dose-dependent decrease in immobility and increase in active coping strategies in the forced swim test similar to that seen with desipramine (2 x 20 mg/kg). There were modest anxiolytic effects of TPM on the EPM and emergence tests. With acute administration, TPM is moderately effective and relatively selective in reducing the drive to consume alcohol in Wistar rats. This anti-alcohol effect is modest in comparison with naloxone and appears to dissipate under conditions of chronic treatment and ad libitum alcohol access. A marked antidepressant-like effect in the forced swim test and partial anxiolytic effects in other animal models suggests that TPM may be a beneficial treatment for affective disorders. These preliminary results suggest further research is warranted to resolve the mechanisms involved in TPM modulation of both mood and alcohol consumption.

The development of a Space Shuttle Research Animal Holding Facility

NASA Technical Reports Server (NTRS)

Jagow, R. B.

1980-01-01

The ability to maintain the well being of experiment animals is of primary importance to the successful attainment of life sciences flight experiment goals. To assist scientists in the conduct of life sciences flight experiments, a highly versatile Research Animal Holding Facility (RAHF) is being developed for use on Space Shuttle/Spacelab missions. This paper describes the design of the RAHF system, which in addition to providing general housing for various animal species, approximating the environment found in ground based facilities, is designed to minimize disturbances of the specimens by vehicle and mission operations. Life-sustaining capabilities such as metabolic support and environmental control are provided. RAHF is reusable and is a modular concept to accommodate animals of different sizes. The basic RAHF system will accommodate a combination of 24 500-g rats or 144 mice or a mixed number of rats and mice. An alternative design accommodates four squirrel monkeys. The entire RAHF system is housed in a single ESA rack. The animal cages are in drawers which are removable for easy access to the animals. Each cage contains a waste management system, a feeding system and a watering system all of which will operate in zero or one gravity.

50 CFR 648.77 - Cage identification.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Atlantic Surf Clam and Ocean Quahog Fisheries § 648.77 Cage identification. Except as provided in § 648.78... for surfclams and ocean quahogs: (a) Tagging. Before offloading, all cages that contain surfclams or... Administrator. (g) Transfer. See § 648.74(b)(2). (h) Presumptions. Surfclams and ocean quahogs found in cages...

50 CFR 648.77 - Cage identification.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Atlantic Surf Clam and Ocean Quahog Fisheries § 648.77 Cage identification. Except as provided in § 648.78... for surfclams and ocean quahogs: (a) Tagging. Before offloading, all cages that contain surfclams or... Administrator. (g) Transfer. See § 648.74(b)(2). (h) Presumptions. Surfclams and ocean quahogs found in cages...

50 CFR 648.77 - Cage identification.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Atlantic Surf Clam and Ocean Quahog Fisheries § 648.77 Cage identification. Except as provided in § 648.78... for surfclams and ocean quahogs: (a) Tagging. Before offloading, all cages that contain surfclams or... Administrator. (g) Transfer. See § 648.74(b)(2). (h) Presumptions. Surfclams and ocean quahogs found in cages...

Anterior lumbar fusion with titanium threaded and mesh interbody cages.

PubMed

Rauzzino, M J; Shaffrey, C I; Nockels, R P; Wiggins, G C; Rock, J; Wagner, J

1999-12-15

The authors report their experience with 42 patients in whom anterior lumbar fusion was performed using titanium cages as a versatile adjunct to treat a wide variety of spinal deformity and pathological conditions. These conditions included congenital, degenerative, iatrogenic, infectious, traumatic, and malignant disorders of the thoracolumbar spine. Fusion rates and complications are compared with data previously reported in the literature. Between July 1996 and July 1999 the senior authors (C.I.S., R.P.N., and M.J.R.) treated 42 patients by means of a transabdominal extraperitoneal (13 cases) or an anterolateral extraperitoneal approach (29 cases), 51 vertebral levels were fused using titanium cages packed with autologous bone. All vertebrectomies (27 cases) were reconstructed using a Miami Moss titanium mesh cage and Kaneda instrumentation. Interbody fusion (15 cases) was performed with either the BAK titanium threaded interbody cage (in 13 patients) or a Miami Moss titanium mesh cage (in two patients). The average follow-up period was 14.3 months. Seventeen patients had sustained a thoracolumbar burst fracture, 12 patients presented with degenerative spinal disorders, six with metastatic tumor, four with spinal deformity (one congenital and three iatrogenic), and three patients presented with spinal infections. In five patients anterior lumbar interbody fusion (ALIF) was supplemented with posterior segmental fixation at the time of the initial procedure. Of the 51 vertebral levels treated, solid arthrodesis was achieved in 49, a 96% fusion rate. One case of pseudarthrosis occurred in the group treated with BAK cages; the diagnosis was made based on the patient's continued mechanical back pain after undergoing L4-5 ALIF. The patient was treated with supplemental posterior fixation, and successful fusion occurred uneventfully with resolution of her back pain. In the group in which vertebrectomy was performed there was one case of fusion failure in a patient with metastatic breast cancer who had undergone an L-3 corpectomy with placement of a mesh cage. Although her back pain was immediately resolved, she died of systemic disease 3 months after surgery and before fusion could occur. Complications related to the anterior approach included two vascular injuries (two left common iliac vein lacerations); one injury to the sympathetic plexus; one case of superficial phlebitis; two cases of prolonged ileus (greater than 48 hours postoperatively); one anterior femoral cutaneous nerve palsy; and one superficial wound infection. No deaths were directly related to the surgical procedure. There were no cases of dural laceration and no nerve root injury. There were no cases of deep venous thrombosis, pulmonary embolus, retrograde ejaculation, abdominal hernia, bowel or ureteral injury, or deep wound infection. Fusion-related complications included an iliac crest hematoma and prolonged donor-site pain in one patient. There were no complications related to placement or migration of the cages, but there was one case of screw fracture of the Kaneda device that did not require revision. The authors conclude that anterior lumbar fusion performed using titanium interbody or mesh cages, packed with autologous bone, is an effective, safe method to achieve fusion in a wide variety of pathological conditions of the thoracolumbar spine. The fusion rate of 96% compares favorably with results reported in the literature. The complication rate mirrors the low morbidity rate associated with the anterior approach. A detailed study of clinical outcomes is in progress. Patient selection and strategies for avoiding complication are discussed.

Bored to Death: Community-Wide Effect of Predation on a Foundation Species in a Low-Disturbance Arctic Subtidal System.

PubMed

Yakovis, Eugeniy; Artemieva, Anna

2015-01-01

The strength of top-down control by consumers is predicted to decrease with latitude, but most data confirming this assumption come from latitudes <60°, while empirical studies of predation in sub-arctic and arctic marine habitats are few. A barnacle Balanus crenatus is a native foundation species in the shallow subtidal of the White Sea (65° N), hosting a diverse (250+ species) assemblage of macrobenthic organisms. On mixed sediments live barnacles share primary substrates (shells and gravel) with numerous empty barnacle tests, 7% of which had drill holes of an unidentified origin. We manipulated the densities of (i) adult muricid whelks Boreotrophon clathratus (of previously unknown feeding habits), to check if they prey on barnacles, (ii) other predators to reveal their effect on juvenile Boreotrophon, and (iii) empty tests to assess the community-wide effect of predation on barnacles. The abundance of drilled empty tests in the field correlated with that of Boreotrophon. A year-long caging experiment clearly confirmed predation, showing the highest barnacle mortality and proportion of drilled tests in whelk enclosures, and the lowest--in predator exclosure treatments. Boreotrophon preferred the barnacles attached to conspecifics to those from primary substrates. Because of its scarcity Boreotrophon had a minor direct effect on barnacle abundance in the field. Yet, initially defaunated empty tests and live barnacles developed markedly different macrobenthic assemblages, suggesting a strong indirect effect of the predation. Juvenile Boreotrophon were 5-6 times less abundant in open and partial cages than in exclosures and enclosures, which indicates that the recruitment and, consequently, the abundance of Boreotrophon and its predation on Balanus are top-down controlled by apex predators. In contrast, in tropical and temperate intertidal the predation on barnacles is stronger and primarily limited by environmental stress and prey availability.

Incorporation of organometallic Ru complexes into apo-ferritin cage.

PubMed

Takezawa, Yusuke; Böckmann, Philipp; Sugi, Naoki; Wang, Ziyue; Abe, Satoshi; Murakami, Tatsuya; Hikage, Tatsuo; Erker, Gerhard; Watanabe, Yoshihito; Kitagawa, Susumu; Ueno, Takafumi

2011-03-14

Spherical protein cages such as an iron storage protein, ferritin, have great potential as nanometer-scale capsules to assemble and store metal ions and complexes. We report herein the synthesis of a composite of an apo-ferritin cage and Ru(p-cymene) complexes. Ru complexes were efficiently incorporated into the ferritin cavity without degradation of its cage structure. X-Ray crystallography revealed that the Ru complexes were immobilized on the interior surface of the cage mainly by the coordination of histidine residues.

[Effect of air-electric fields on driving and reaction patterns. Test subjects in the car driving simulator (author's transl)].

PubMed

Anselm, D; Danner, M; Kirmaier, N; König, H L; Müller-Limmroth, W; Reis, A; Schauerte, W

1977-06-10

In the relevant frequency range of about 10 Hertz cars can be considered very largely as Faraday cages and consequently as screens against air-electric fields. This may have a negative influence on driving and reaction patterns as a result. In an extensive investigation 48 subjects in a driving simulator were exposed to definite artificially produced air-electric fields. The self-rating of the performance and concentration of the subjects, reaction times and driving errors were determined. While the reaction times remained practically constant, the driving behavior of the subjects improved.

Dietary L-arginine supplementation modulates lipopolysaccharide-induced systemic inflammatory response in broiler chickens

USDA-ARS?s Scientific Manuscript database

This study was conducted to evaluate whether dietary supplementation with L-arginine (Arg) could attenuate lipopolysaccharide (LPS)-induced systemic inflammatory response through LPS/TLR-4 signaling pathway in broilers. The experiment was designed as a 2 × 3 factorial arrangement (n = 8 cages/treatm...

Genome Sequence of Pantoea annatis strain CFH 7-1, which is associated with a vector-borne cotton fruit disease

USDA-ARS?s Scientific Manuscript database

Pantoea ananatis is a bacterium with versatile niches that vary from pathogenic to beneficial. We present the genome of strain CFH 7-1, which was recovered from a diseased greenhouse cotton boll previously caged with a field-collected cotton fleahopper (Pseudatomoscelis seriatus). These data will ...

Effects of an Extended Cage-change Interval on Ammonia Levels and Reproduction in Mongolian Gerbils (Meriones unguiculatus).

PubMed

McCullagh, Elizabeth A; McCullagh, Peter; Klug, Achim; Leszczynski, Jori K; Fong, Derek L

2017-11-01

Prompted by the cage cleanliness of Mongolian gerbils (Meriones unguiculatus), we evaluated a prolonged cage-change interval. We compared the effects of a 2-wk and 6-wk cage-change schedule on ammonia levels, temperature, humidity, and reproductive performance in breeding pairs housed in IVC. We hypothesized that ammonia levels would remain below our threshold for cage changing and that reproductive performance would not be affected. Although ammonia levels increased over time, they remained low (less than 5 ppm) over the 6-wk period. In addition, the 6-wk cage-change interval did not significantly influence reproductive parameters, such as average pup weaning weight, number of litters, and number of pups per litter. We conclude that an extended cage-change interval (6-wk) can be used for gerbils without significant increases in intracage ammonia levels or effects on reproduction.

Blower augmentor for power oil and power gas burners

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

Fisher, L.A.

1987-07-14

An oil burner is described in combination: (a) a blower comprising a scroll housing and a driven squirrel cage, the squirrel cage having an interior air space, and having blades disposed around space and constituting an air impeller; (b) the scroll housing having a tangential air outlet, and further comprising a spiral wall encircling the squirrel cage; (c) a stationary barrier wall mounted in the housing and extending into the interior air space of the squirrel cage. The barrier wall extends outward from and with respect to a central axial area of the squirrel cage to a location adjacent themore » blades; (d) the housing is wider than the squirrel cage in axial dimension, to provide an end space between the squirrel cage and the housing, in which end space air tends to recirculate in the housing; and (e) support and baffle means disposed in the end space between the housing and squirrel cage, for mounting the barrier wall and for redirecting in outward directions a portion of the circularly travelling recirculating air in the housing.« less

Testing and Comparative Evaluation of Space Shuttle Main Engine Flowmeter Bearings

NASA Technical Reports Server (NTRS)

Hissam, Andy; Leberman, Mike; McLeroy, Rick

2005-01-01

This paper provides a summary of testing of Space Shuttle Main Engine (SSME) flowmeter bearings and cage material. These tests were con&cM over a several month period in 2004 at the Marshall Space Flight Center. The test program's primary objective was to compare the performance of bearings using the existing cage material and bearings using a proposed replacement cage material. In order to meet the test objectives for this program, a flowmeter test rig was designed and fabricated to measure both breakaway and running torque for a flowmeter assembly. Other test parameters,,such as motor current and shaft speed, were also recorded and provide a means of comparing bearing performance. The flowmeter and bearings were tested in liquid hydrogen to simulate the flowmeter's operating environment as closely as possible. Based on the results from this testing, the bearings with the existing cage material are equivalent to the bearings with the proposed replacement cage material. No major differences exist between the old and new cage materials. Therefore, the new cage material is a suitable replacement for the existing cage material.

Synthesis, structural characterisation and magnetic studies of polymetallic iron phosphonate cages.

PubMed

Khanra, Sumit; Helliwell, Madeleine; Tuna, Floriana; McInnes, Eric J L; Winpenny, Richard E P

2009-08-21

Four new polymetallic iron(III) phosphonate cages have been made and structurally characterised. These are an octanuclear cage [Fe(8)O(3)(OH)(2)(O(2)C(t)Bu)(11)(PhCH(2)PO(3))(3)(py)(3)], a decanuclear cage [Fe(10)O(2)(OH)(8)(O(2)C(t)Bu)(10)(PhCH(2)PO(3))(4)(pip)(2)], a heterometallic cage [Fe(6)Li(5)(mu(3)-O)(2)((t)BuPO(3))(6)(O(2)C(t)Bu)(8)(MeOH)(2)(Py)(4)] and a tridecanuclear cage [Et(3)NH](2)[Fe(13)(mu(3)-O)(3)(mu(2)-OH)(7)((t)BuPO(3))(7)(Me(3)CCO(2))(14)(H(2)O)] (pip = piperidine, py = pyridine). Magnetic studies of the first three compounds show anti-ferromagnetic exchange between the iron(III) centers leading to diamagnetic ground states for the homometallic cages. For the heterometallic cage, the six Fe(III) centers are arranged in two triangles, and each triangle has an S = 1/2 spin ground state.

Potential of environmental DNA to evaluate Northern pike (Esox lucius) eradication efforts: An experimental test and case study

USGS Publications Warehouse

Dunker, Kristine J.; Sepulveda, Adam; Massengill, Robert L.; Olsen, Jeffrey B.; Russ, Ora L.; Wenburg, John K.; Antonovich, Anton

2016-01-01

Determining the success of invasive species eradication efforts is challenging because populations at very low abundance are difficult to detect. Environmental DNA (eDNA) sampling has recently emerged as a powerful tool for detecting rare aquatic animals; however, detectable fragments of DNA can persist over time despite absence of the targeted taxa and can therefore complicate eDNA sampling after an eradication event. This complication is a large concern for fish eradication efforts in lakes since killed fish can sink to the bottom and slowly decay. DNA released from these carcasses may remain detectable for long periods. Here, we evaluated the efficacy of eDNA sampling to detect invasive Northern pike (Esox lucius) following piscicide eradication efforts in southcentral Alaskan lakes. We used field observations and experiments to test the sensitivity of our Northern pike eDNA assay and to evaluate the persistence of detectable DNA emitted from Northern pike carcasses. We then used eDNA sampling and traditional sampling (i.e., gillnets) to test for presence of Northern pike in four lakes subjected to a piscicide-treatment designed to eradicate this species. We found that our assay could detect an abundant, free-roaming population of Northern pike and could also detect low-densities of Northern pike held in cages. For these caged Northern pike, probability of detection decreased with distance from the cage. We then stocked three lakes with Northern pike carcasses and collected eDNA samples 7, 35 and 70 days post-stocking. We detected DNA at 7 and 35 days, but not at 70 days. Finally, we collected eDNA samples ~ 230 days after four lakes were subjected to piscicide-treatments and detected Northern pike DNA in 3 of 179 samples, with a single detection at each of three lakes, though we did not catch any Northern pike in gillnets. Taken together, we found that eDNA can help to inform eradication efforts if used in conjunction with multiple lines of inquiry and sampling is delayed long enough to allow full degradation of DNA in the water.

Potential of Environmental DNA to Evaluate Northern Pike (Esox lucius) Eradication Efforts: An Experimental Test and Case Study.

PubMed

Dunker, Kristine J; Sepulveda, Adam J; Massengill, Robert L; Olsen, Jeffrey B; Russ, Ora L; Wenburg, John K; Antonovich, Anton

2016-01-01

Determining the success of invasive species eradication efforts is challenging because populations at very low abundance are difficult to detect. Environmental DNA (eDNA) sampling has recently emerged as a powerful tool for detecting rare aquatic animals; however, detectable fragments of DNA can persist over time despite absence of the targeted taxa and can therefore complicate eDNA sampling after an eradication event. This complication is a large concern for fish eradication efforts in lakes since killed fish can sink to the bottom and slowly decay. DNA released from these carcasses may remain detectable for long periods. Here, we evaluated the efficacy of eDNA sampling to detect invasive Northern pike (Esox lucius) following piscicide eradication efforts in southcentral Alaskan lakes. We used field observations and experiments to test the sensitivity of our Northern pike eDNA assay and to evaluate the persistence of detectable DNA emitted from Northern pike carcasses. We then used eDNA sampling and traditional sampling (i.e., gillnets) to test for presence of Northern pike in four lakes subjected to a piscicide-treatment designed to eradicate this species. We found that our assay could detect an abundant, free-roaming population of Northern pike and could also detect low-densities of Northern pike held in cages. For these caged Northern pike, probability of detection decreased with distance from the cage. We then stocked three lakes with Northern pike carcasses and collected eDNA samples 7, 35 and 70 days post-stocking. We detected DNA at 7 and 35 days, but not at 70 days. Finally, we collected eDNA samples ~ 230 days after four lakes were subjected to piscicide-treatments and detected Northern pike DNA in 3 of 179 samples, with a single detection at each of three lakes, though we did not catch any Northern pike in gillnets. Taken together, we found that eDNA can help to inform eradication efforts if used in conjunction with multiple lines of inquiry and sampling is delayed long enough to allow full degradation of DNA in the water.

Potential of Environmental DNA to Evaluate Northern Pike (Esox lucius) Eradication Efforts: An Experimental Test and Case Study

PubMed Central

Dunker, Kristine J.; Sepulveda, Adam J.; Massengill, Robert L.; Olsen, Jeffrey B.; Russ, Ora L.; Wenburg, John K.; Antonovich, Anton

2016-01-01

Determining the success of invasive species eradication efforts is challenging because populations at very low abundance are difficult to detect. Environmental DNA (eDNA) sampling has recently emerged as a powerful tool for detecting rare aquatic animals; however, detectable fragments of DNA can persist over time despite absence of the targeted taxa and can therefore complicate eDNA sampling after an eradication event. This complication is a large concern for fish eradication efforts in lakes since killed fish can sink to the bottom and slowly decay. DNA released from these carcasses may remain detectable for long periods. Here, we evaluated the efficacy of eDNA sampling to detect invasive Northern pike (Esox lucius) following piscicide eradication efforts in southcentral Alaskan lakes. We used field observations and experiments to test the sensitivity of our Northern pike eDNA assay and to evaluate the persistence of detectable DNA emitted from Northern pike carcasses. We then used eDNA sampling and traditional sampling (i.e., gillnets) to test for presence of Northern pike in four lakes subjected to a piscicide-treatment designed to eradicate this species. We found that our assay could detect an abundant, free-roaming population of Northern pike and could also detect low-densities of Northern pike held in cages. For these caged Northern pike, probability of detection decreased with distance from the cage. We then stocked three lakes with Northern pike carcasses and collected eDNA samples 7, 35 and 70 days post-stocking. We detected DNA at 7 and 35 days, but not at 70 days. Finally, we collected eDNA samples ~ 230 days after four lakes were subjected to piscicide-treatments and detected Northern pike DNA in 3 of 179 samples, with a single detection at each of three lakes, though we did not catch any Northern pike in gillnets. Taken together, we found that eDNA can help to inform eradication efforts if used in conjunction with multiple lines of inquiry and sampling is delayed long enough to allow full degradation of DNA in the water. PMID:27626271