Science.gov

Sample records for conditional mutualism limits

  1. A strong conditional mutualism limits and enhances seed dispersal and germination of a tropical palm.

    PubMed

    Klinger, Rob; Rejmánek, Marcel

    2010-04-01

    Seed predation and seed dispersal can have strong effects on early life history stages of plants. These processes have often been studied as individual effects, but the degree to which their relative importance co-varies with seed predator abundance and how this influences seed germination rates is poorly understood. Therefore, we used a combination of observations and field experiments to determine the degree to which germination rates of the palm Astrocaryum mexicanum varied with abundance of a small mammal seed predator/disperser, Heteromys desmarestianus, in a lowland tropical forest. Patterns of abundance of the two species were strongly related; density of H. desmarestianus was low in sites with low density of A. mexicanum and vice versa. Rates of predation and dispersal of A. mexicanum seeds depended on abundance of H. desmarestianus; sites with high densities of H. desmarestianus had the highest rates of seed predation and lowest rates of seed germination, but a greater total number of seeds were dispersed and there was greater density of seedlings, saplings, and adults of A. mexicanum in these sites. When abundance of H. desmarestianus was experimentally reduced, rates of seed predation decreased, but so did dispersal of A. mexicanum seeds. Critically, rates of germination of dispersed seeds were 5 times greater than undispersed seeds. The results suggest that the relationship between A. mexicanum and H. desmarestianus is a conditional mutualism that results in a strong local effect on the abundance of each species. However, the magnitude and direction of these effects are determined by the relative strength of opposing, but related, mechanisms. A. mexicanum nuts provide H. desmarestianus with a critical food resource, and while seed predation on A. mexicanum nuts by H. desmarestianus is very intense, A. mexicanum ultimately benefits because of the relatively high germination rates of its seeds that are dispersed by H. desmarestianus.

  2. A strong conditional mutualism limits and enhances seed dispersal and germination of a tropical palm

    USGS Publications Warehouse

    Klinger, R.; Rejmanek, M.

    2010-01-01

    Seed predation and seed dispersal can have strong effects on early life history stages of plants. These processes have often been studied as individual effects, but the degree to which their relative importance co-varies with seed predator abundance and how this influences seed germination rates is poorly understood. Therefore, we used a combination of observations and field experiments to determine the degree to which germination rates of the palm Astrocaryum mexicanum varied with abundance of a small mammal seed predator/disperser, Heteromysdesmarestianus, in a lowland tropical forest. Patterns of abundance of the two species were strongly related; density of H. desmarestianus was low in sites with low density of A. mexicanum and vice versa. Rates of predation and dispersal of A. mexicanum seeds depended on abundance of H. desmarestianus; sites with high densities of H. desmarestianus had the highest rates of seed predation and lowest rates of seed germination, but a greater total number of seeds were dispersed and there was greater density of seedlings, saplings, and adults of A. mexicanum in these sites. When abundance of H. desmarestianus was experimentally reduced, rates of seed predation decreased, but so did dispersal of A. mexicanum seeds. Critically, rates of germination of dispersed seeds were 5 times greater than undispersed seeds. The results suggest that the relationship between A. mexicanum and H. desmarestianus is a conditional mutualism that results in a strong local effect on the abundance of each species. However, the magnitude and direction of these effects are determined by the relative strength of opposing, but related, mechanisms. A. mexicanum nuts provide H. desmarestianus with a critical food resource, and while seed predation on A. mexicanum nuts by H. desmarestianus is very intense, A. mexicanum ultimately benefits because of the relatively high germination rates of its seeds that are dispersed by H. desmarestianus. ?? The Author(s) 2010.

  3. 26 CFR 1.809-8 - Limitation on deductions for certain mutualization distributions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... mutualization distributions. 1.809-8 Section 1.809-8 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF... Limitation on deductions for certain mutualization distributions. (a) Deduction not to reduce taxable... distributions. This limitation provides that such deduction shall not exceed the amount (if any) by which...

  4. Conditional mutual information of bipartite unitaries and scrambling

    NASA Astrophysics Data System (ADS)

    Ding, Dawei; Hayden, Patrick; Walter, Michael

    2016-12-01

    One way to diagnose chaos in bipartite unitary channels is via the tripartite information of the corresponding Choi state, which for certain choices of the subsystems reduces to the negative conditional mutual information (CMI). We study this quantity from a quantum information-theoretic perspective to clarify its role in diagnosing scrambling. When the CMI is zero, we find that the channel has a special normal form consisting of local channels between individual inputs and outputs. However, we find that arbitrarily low CMI does not imply arbitrary proximity to a channel of this form, although it does imply a type of approximate recoverability of one of the inputs. When the CMI is maximal, we find that the residual channel from an individual input to an individual output is completely depolarizing when the other input is maximally mixed. However, we again find that this result is not robust. We also extend some of these results to the multipartite case and to the case of Haar-random pure input states. Finally, we look at the relationship between tripartite information and its Rényi-2 version which is directly related to out-of-time-order correlation functions. In particular, we demonstrate an arbitrarily large gap between the two quantities.

  5. Limiting cheaters in mutualism: evidence from hybridization between mutualist and cheater yucca moths.

    PubMed

    Segraves, Kari A; Althoff, David M; Pellmyr, Olle

    2005-10-22

    Mutualisms are balanced antagonistic interactions where both species gain a net benefit. Because mutualisms generate resources, they can be exploited by individuals that reap the benefits of the interaction without paying any cost. The presence of such 'cheaters' may have important consequences, yet we are only beginning to understand how cheaters evolve from mutualists and how their evolution may be curtailed within mutualistic lineages. The yucca-yucca moth pollination mutualism is an excellent model in this context as there have been two origins of cheating from within the yucca moth lineage. We used nuclear and mitochondrial DNA markers to examine genetic structure in a moth population where a cheater species is parapatric with a resident pollinator. The results revealed extensive hybridization between pollinators and cheaters. Hybrids were genetically intermediate to parental populations, even though all individuals in this population had a pollinator phenotype. The results suggest that mutualisms can be stable in the face of introgression of cheater genes and that the ability of cheaters to invade a given mutualism may be more limited than previously appreciated.

  6. Limiting cheaters in mutualism: evidence from hybridization between mutualist and cheater yucca moths

    PubMed Central

    Segraves, Kari A; Althoff, David M; Pellmyr, Olle

    2005-01-01

    Mutualisms are balanced antagonistic interactions where both species gain a net benefit. Because mutualisms generate resources, they can be exploited by individuals that reap the benefits of the interaction without paying any cost. The presence of such ‘cheaters’ may have important consequences, yet we are only beginning to understand how cheaters evolve from mutualists and how their evolution may be curtailed within mutualistic lineages. The yucca–yucca moth pollination mutualism is an excellent model in this context as there have been two origins of cheating from within the yucca moth lineage. We used nuclear and mitochondrial DNA markers to examine genetic structure in a moth population where a cheater species is parapatric with a resident pollinator. The results revealed extensive hybridization between pollinators and cheaters. Hybrids were genetically intermediate to parental populations, even though all individuals in this population had a pollinator phenotype. The results suggest that mutualisms can be stable in the face of introgression of cheater genes and that the ability of cheaters to invade a given mutualism may be more limited than previously appreciated. PMID:16191630

  7. Oklahoma Retailers' Perspectives on Mutual Benefit Exchange to Limit Point-of-Sale Tobacco Advertisements.

    PubMed

    Chan, Andie; Douglas, Malinda Reddish; Ling, Pamela M

    2015-09-01

    Businesses changing their practices in ways that support tobacco control efforts recently have gained interest, as demonstrated by CVS Health's voluntary policy to end tobacco sales. Point-of-sale (POS) advertisements are associated with youth smoking initiation, increased tobacco consumption, and reduced quit attempts among smokers. There is interest in encouraging retailers to limit tobacco POS advertisements voluntarily. This qualitative exploratory study describes Oklahoma tobacco retailers' perspectives on a mutual benefit exchange approach, and preferred message and messenger qualities that would entice them to take voluntary action to limit tobacco POS advertisements. This study found that mutual benefit exchange could be a viable option along with education and law as strategies to create behavior change among tobacco retailers. Many retailers stated that they would be willing to remove noncontractual POS advertisements for a 6-month commitment period when presented with mutual exchange benefit, tailored message, and appropriate messenger. Mutual benefit exchange, as a behavior change strategy to encourage voluntary removal of POS tobacco advertisements, was acceptable to retailers, could enhance local tobacco control in states with preemption, and may contribute to setting the foundation for broader legislative efforts.

  8. Oklahoma Retailers’ Perspectives on Mutual Benefit Exchange to Limit Point-of-Sale Tobacco Advertisements

    PubMed Central

    Chan, Andie; Douglas, Malinda Reddish; Ling, Pamela M.

    2015-01-01

    Businesses changing their practices in ways that support tobacco control efforts recently have gained interest, as demonstrated by CVS Health’s voluntary policy to end tobacco sales. Point of sale (POS) advertisements are associated with youth smoking initiation, increased tobacco consumption, and reduced quit attempts among smokers. There is interest in encouraging retailers to limit tobacco POS advertisements voluntarily. This qualitative exploratory study describes Oklahoma tobacco retailers’ perspectives on a mutual benefit exchange approach, and preferred message and messenger qualities that would entice them to take voluntary action to limit tobacco POS advertisements. This study found mutual benefit exchange could be a viable option along with education and law as strategies to create behavior change among tobacco retailers. Many retailers stated that they would be willing to remove non-contractual POS advertisements for a six-month commitment period when presented with mutual exchange benefit, tailored message, and appropriate messenger. Mutual benefit exchange, as a behavior change strategy to encourage voluntary removal of POS tobacco advertisements, was acceptable to retailers, could enhance local tobacco control in states with preemption, and may contribute to setting the foundation for broader legislative efforts. PMID:25767197

  9. Mutual Comparative Filtering for Change Detection in Videos with Unstable Illumination Conditions

    NASA Astrophysics Data System (ADS)

    Sidyakin, Sergey V.; Vishnyakov, Boris V.; Vizilter, Yuri V.; Roslov, Nikolay I.

    2016-06-01

    In this paper we propose a new approach for change detection and moving objects detection in videos with unstable, abrupt illumination changes. This approach is based on mutual comparative filters and background normalization. We give the definitions of mutual comparative filters and outline their strong advantage for change detection purposes. Presented approach allows us to deal with changing illumination conditions in a simple and efficient way and does not have drawbacks, which exist in models that assume different color transformation laws. The proposed procedure can be used to improve a number of background modelling methods, which are not specifically designed to work under illumination changes.

  10. Estimating coupling direction between neuronal populations with permutation conditional mutual information.

    PubMed

    Li, Xiaoli; Ouyang, Gaoxiang

    2010-08-15

    To further understand functional connectivity in the brain, we need to identify the coupling direction between neuronal signals recorded from different brain areas. In this paper, we present a novel methodology based on permutation analysis and conditional mutual information for estimation of a directionality index between two neuronal populations. First, the reliability of this method is numerically assessed with a coupled mass neural model; the simulations show that this method is superior to the conditional mutual information method and the Granger causality method for identifying the coupling direction between unidirectional or bidirectional neuronal populations that are generated by the mass neuronal model. The method is also applied to investigate the coupling direction between neuronal populations in CA1 and CA3 in the rat hippocampal tetanus toxin model of focal epilepsy; the propagation direction of the seizure events could be elucidated through this coupling direction estimation method. All together, these results suggest that the permutation conditional mutual information method is a promising technique for estimating directional coupling between mutually interconnected neuronal populations.

  11. Decision Trees for Continuous Data and Conditional Mutual Information as a Criterion for Splitting Instances.

    PubMed

    Drakakis, Georgios; Moledina, Saadiq; Chomenidis, Charalampos; Doganis, Philip; Sarimveis, Haralambos

    2016-01-01

    Decision trees are renowned in the computational chemistry and machine learning communities for their interpretability. Their capacity and usage are somewhat limited by the fact that they normally work on categorical data. Improvements to known decision tree algorithms are usually carried out by increasing and tweaking parameters, as well as the post-processing of the class assignment. In this work we attempted to tackle both these issues. Firstly, conditional mutual information was used as the criterion for selecting the attribute on which to split instances. The algorithm performance was compared with the results of C4.5 (WEKA's J48) using default parameters and no restrictions. Two datasets were used for this purpose, DrugBank compounds for HRH1 binding prediction and Traditional Chinese Medicine formulation predicted bioactivities for therapeutic class annotation. Secondly, an automated binning method for continuous data was evaluated, namely Scott's normal reference rule, in order to allow any decision tree to easily handle continuous data. This was applied to all approved drugs in DrugBank for predicting the RDKit SLogP property, using the remaining RDKit physicochemical attributes as input.

  12. The Curious Case of the Camelthorn: Competition, Coexistence, and Nest-Site Limitation in a Multispecies Mutualism.

    PubMed

    Campbell, Heather; Fellowes, Mark D E; Cook, James M

    2015-12-01

    Myrmecophyte plants house ants within domatia in exchange for protection against herbivores. Ant-myrmecophyte mutualisms exhibit two general patterns due to competition between ants for plant occupancy: (i) domatia nest sites are a limiting resource and (ii) each individual plant hosts one ant species at a time. However, individual camelthorn trees (Vachellia erioloba) typically host two to four ant species simultaneously, often coexisting in adjacent domatia on the same branch. Such fine-grain spatial coexistence brings into question the conventional wisdom on ant-myrmecophyte mutualisms. Camelthorn ants appear not to be nest-site limited, despite low abundance of suitable domatia, and have random distributions of nest sites within and across trees. These patterns suggest a lack of competition between ants for domatia and contrast strongly with other ant-myrmecophyte systems. Comparison of this unusual case with others suggests that spatial scale is crucial to coexistence or competitive exclusion involving multiple ant species. Furthermore, coexistence may be facilitated when co-occurring ant species diverge strongly on at least one niche axis. Our conclusions provide recommendations for future ant-myrmecophyte research, particularly in utilizing multispecies systems to further our understanding of mutualism biology.

  13. Commensalism or mutualism: conditional outcomes in a branchiobdellid-crayfish symbiosis.

    PubMed

    Lee, Ju Hyung; Kim, Tae Won; Choe, Jae Chun

    2009-02-01

    A growing body of evidence suggests that the costs and benefits involved in cleaning interactions can vary over space and time depending on the environmental conditions. However, whether the same cleaners actually induce variable net outcomes in terms of host fitness remains unclear to date. Branchiobdellid annelids are generally regarded as commensals or rarely parasites of their freshwater crayfish hosts, but a recent study suggests that they may also function as cleaning organisms. Under natural conditions, crayfish can experience fouling of the exposed surfaces of their exoskeletons and their gills (e.g., epibiosis) by various epibionts and particles of organic debris, and branchiobdellids graze on these sources of fouling. Here, we examined the extent to which variation in fouling pressure in the environment alters the outcome of the interaction between branchiobdellids and their crayfish host Cambaroide similis. A series of manipulations were performed in artificial environments designed to simulate either high or low fouling pressure. We used crayfish growth rates and mortality as direct measurements of the net costs and benefits of cleaning. Branchiobdellids had no significant effect on crayfish growth or mortality when cultured under low fouling pressure. However, their presence had a significant positive impact on host growth rates when cultured under high fouling pressure. These results suggest that the relationship between crayfish and branchiobdellids can fluctuate between commensalism and mutualism depending mainly on the environmental fouling pressure. We hypothesize that the outcome of cleaning interactions may largely depend on the factors directly related to the need for cleaning, such as parasite loads or fouling pressure.

  14. Mutual information detects a decreased interdependence between RR and SAP in orthostatic intolerance after microgravity condition.

    PubMed

    Raimondi, G; Chillemi, S; Michelassi, C; Di Garbo, A; Varanini, M; Legramante, J; Balocchi, R

    2002-07-01

    Orthostatic intolerance is the most serious symptom of cardiovascular deconditioning induced by microgravity. However, the exact mechanisms underlying these alterations have not been completely clarified. Several methods for studying the time series of systolic arterial pressure and RR interval have been proposed both in the time and in the frequency domain. However, these methods did not produce definitive results. In fact heart rate and arterial pressure show a complex pattern of global variability which is likely due to non linear feedback which involves the autonomic nervous system and to "stochastic" influences. Aim of this study was to evaluate the degree of interdependence between the mechanisms responsible for the variability of SAP and RR signals in subjects exposed to head down (HD). This quantification was achieved by using Mutual Information (MI).

  15. Bootstrap rank-ordered conditional mutual information (broCMI): A nonlinear input variable selection method for water resources modeling

    NASA Astrophysics Data System (ADS)

    Quilty, John; Adamowski, Jan; Khalil, Bahaa; Rathinasamy, Maheswaran

    2016-03-01

    The input variable selection problem has recently garnered much interest in the time series modeling community, especially within water resources applications, demonstrating that information theoretic (nonlinear)-based input variable selection algorithms such as partial mutual information (PMI) selection (PMIS) provide an improved representation of the modeled process when compared to linear alternatives such as partial correlation input selection (PCIS). PMIS is a popular algorithm for water resources modeling problems considering nonlinear input variable selection; however, this method requires the specification of two nonlinear regression models, each with parametric settings that greatly influence the selected input variables. Other attempts to develop input variable selection methods using conditional mutual information (CMI) (an analog to PMI) have been formulated under different parametric pretenses such as k nearest-neighbor (KNN) statistics or kernel density estimates (KDE). In this paper, we introduce a new input variable selection method based on CMI that uses a nonparametric multivariate continuous probability estimator based on Edgeworth approximations (EA). We improve the EA method by considering the uncertainty in the input variable selection procedure by introducing a bootstrap resampling procedure that uses rank statistics to order the selected input sets; we name our proposed method bootstrap rank-ordered CMI (broCMI). We demonstrate the superior performance of broCMI when compared to CMI-based alternatives (EA, KDE, and KNN), PMIS, and PCIS input variable selection algorithms on a set of seven synthetic test problems and a real-world urban water demand (UWD) forecasting experiment in Ottawa, Canada.

  16. Limitations in Life Participation and Independence Due to Secondary Conditions

    ERIC Educational Resources Information Center

    Koritsas, Stella; Iacono, Teresa

    2009-01-01

    The effects of secondary conditions across adults with autism, Down syndrome, and cerebral palsy were explored in terms of overall limitation in life participation and independence, changes over time, and the degree and nature of limitation in specific secondary conditions. Information was obtained for 35 adults with autism, 49 with Down syndrome,…

  17. Mutual interactions between objects oscillating in isotopically pure superfluid 4He in the T → 0 limit

    NASA Astrophysics Data System (ADS)

    Garg, D.; Efimov, V. B.; Giltrow, M.; McClintock, P. V. E.; Skrbek, L.

    2012-11-01

    We report the results of experiments to explore interactions between physically separated oscillating objects in isotopically pure superfluid 4He at T ˜ 10 mK. The investigations focused mainly on 32 kHz quartz tuning forks, but also consider a nearby 1 kHz oscillating grid. The low-drive linewidth (LDL) and resonant frequency fd of a detector fork were monitored while the maximum velocity of a transmitter fork, separated from the detector by a few mm, was varied over a wide range. Clear evidence was found for mutual interactions between the two forks, and for the influence of the grid on the forks. Monitoring the detector's LDL and fd provides evidence for a generator critical velocity in the range 0.3<υc1<1.0 cm/s for onset of the detector responses, in addition to a second critical velocity υc2˜13 cm/s probably corresponding to the production of quantum turbulence at the generator. The results are discussed, but are not yet fully understood.

  18. 14 CFR 125.221 - Icing conditions: Operating limitations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Equipment Requirements § 125.221 Icing conditions: Operating limitations. (a) No pilot may take off an... pilot may take off an airplane any time conditions are such that frost, ice, or snow may reasonably be expected to adhere to the airplane unless the pilot has completed the testing required under §...

  19. 14 CFR 125.221 - Icing conditions: Operating limitations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Equipment Requirements § 125.221 Icing conditions: Operating limitations. (a) No pilot may take off an... pilot may take off an airplane any time conditions are such that frost, ice, or snow may reasonably be expected to adhere to the airplane unless the pilot has completed the testing required under §...

  20. 14 CFR 125.221 - Icing conditions: Operating limitations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Equipment Requirements § 125.221 Icing conditions: Operating limitations. (a) No pilot may take off an... pilot may take off an airplane any time conditions are such that frost, ice, or snow may reasonably be expected to adhere to the airplane unless the pilot has completed the testing required under §...

  1. 14 CFR 125.221 - Icing conditions: Operating limitations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Equipment Requirements § 125.221 Icing conditions: Operating limitations. (a) No pilot may take off an... pilot may take off an airplane any time conditions are such that frost, ice, or snow may reasonably be expected to adhere to the airplane unless the pilot has completed the testing required under §...

  2. Reconstruction of limited-angle dual-energy CT using mutual learning and cross-estimation (MLCE)

    NASA Astrophysics Data System (ADS)

    Zhang, Huayu; Xing, Yuxiang

    2016-03-01

    Dual-energy CT (DECT) imaging has gained a lot of attenuation because of its capability to discriminate materials. We proposes a flexible DECT scan strategy which can be realized on a system with general X-ray sources and detectors. In order to lower dose and scanning time, our DECT acquires two projections data sets on two arcs of limited-angular coverage (one for each energy) respectively. Meanwhile, a certain number of rays from two data sets form conjugate sampling pairs. Our reconstruction method for such a DECT scan mainly tackles the consequent limited-angle problem. Using the idea of artificial neural network, we excavate the connection between projections at two different energies by constructing a relationship between the linear attenuation coefficient of the high energy and that of the low one. We use this relationship to cross-estimate missing projections and reconstruct attenuation images from an augmented data set including projections at views covered by itself (projections collected in scanning) and by the other energy (projections estimated) for each energy respectively. Validated by our numerical experiment on a dental phantom with rather complex structures, our DECT is effective in recovering small structures in severe limited-angle situations. This DECT scanning strategy can much broaden DECT design in reality.

  3. 14 CFR 135.227 - Icing conditions: Operating limitations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... limitations. (a) No pilot may take off an aircraft that has frost, ice, or snow adhering to any rotor blade... may authorize an airplane to take off and no pilot may take off an airplane any time conditions are such that frost, ice, or snow may reasonably be expected to adhere to the airplane unless the pilot...

  4. 14 CFR 135.227 - Icing conditions: Operating limitations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... limitations. (a) No pilot may take off an aircraft that has frost, ice, or snow adhering to any rotor blade... may authorize an airplane to take off and no pilot may take off an airplane any time conditions are such that frost, ice, or snow may reasonably be expected to adhere to the airplane unless the pilot...

  5. 14 CFR 135.227 - Icing conditions: Operating limitations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... limitations. (a) No pilot may take off an aircraft that has frost, ice, or snow adhering to any rotor blade... may authorize an airplane to take off and no pilot may take off an airplane any time conditions are such that frost, ice, or snow may reasonably be expected to adhere to the airplane unless the pilot...

  6. 14 CFR 135.227 - Icing conditions: Operating limitations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... limitations. (a) No pilot may take off an aircraft that has frost, ice, or snow adhering to any rotor blade... may authorize an airplane to take off and no pilot may take off an airplane any time conditions are such that frost, ice, or snow may reasonably be expected to adhere to the airplane unless the pilot...

  7. On the entropy conditions for some flux limited diffusion equations

    NASA Astrophysics Data System (ADS)

    Caselles, V.

    2011-04-01

    In this paper we give a characterization of the notion of entropy solutions of some flux limited diffusion equations for which we can prove that the solution is a function of bounded variation in space and time. This includes the case of the so-called relativistic heat equation and some generalizations. For them we prove that the jump set consists of fronts that propagate at the speed given by Rankine-Hugoniot condition and we give on it a geometric characterization of the entropy conditions. Since entropy solutions are functions of bounded variation in space once the initial condition is, to complete the program we study the time regularity of solutions of the relativistic heat equation under some conditions on the initial datum. An analogous result holds for some other related equations without additional assumptions on the initial condition.

  8. Frontier mutualism: coevolutionary patterns at the northern range limit of the leaf-cutter ant-fungus symbiosis.

    PubMed

    Mueller, Ulrich G; Mikheyev, Alexander S; Solomon, Scott E; Cooper, Michael

    2011-10-22

    Tropical leaf-cutter ants cultivate the fungus Attamyces bromatificus in a many-to-one, diffuse coevolutionary relationship where ant and fungal partners re-associate frequently over time. To evaluate whether ant-Attamyces coevolution is more specific (tighter) in peripheral populations, we characterized the host-specificities of Attamyces genotypes at their northern, subtropical range limits (southern USA, Mexico and Cuba). Population-genetic patterns of northern Attamyces reveal features that have so far not been observed in the diffusely coevolving, tropical ant-Attamyces associations. These unique features include (i) cases of one-to-one ant-Attamyces specialization that tighten coevolution at the northern frontier; (ii) distributions of genetically identical Attamyces clones over large areas (up to 81 000 km(2), approx. the area of Ireland, Austria or Panama); (iii) admixture rates between Attamyces lineages that appear lower in northern than in tropical populations; and (iv) long-distance gene flow of Attamyces across a dispersal barrier for leaf-cutter ants (ocean between mainland North America and Cuba). The latter suggests that Attamyces fungi may occasionally disperse independently of the ants, contrary to the traditional assumption that Attamyces fungi depend entirely on leaf-cutter queens for dispersal. Peripheral populations in Argentina or at mid-elevation sites in the Andes may reveal additional regional variants in ant-Attamyces coevolution. Studies of such populations are most likely to inform models of coextinctions of obligate mutualistic partners that are doubly stressed by habitat marginality and by environmental change.

  9. Frontier mutualism: coevolutionary patterns at the northern range limit of the leaf-cutter ant–fungus symbiosis

    PubMed Central

    Mueller, Ulrich G.; Mikheyev, Alexander S.; Solomon, Scott E.; Cooper, Michael

    2011-01-01

    Tropical leaf-cutter ants cultivate the fungus Attamyces bromatificus in a many-to-one, diffuse coevolutionary relationship where ant and fungal partners re-associate frequently over time. To evaluate whether ant–Attamyces coevolution is more specific (tighter) in peripheral populations, we characterized the host-specificities of Attamyces genotypes at their northern, subtropical range limits (southern USA, Mexico and Cuba). Population-genetic patterns of northern Attamyces reveal features that have so far not been observed in the diffusely coevolving, tropical ant–Attamyces associations. These unique features include (i) cases of one-to-one ant–Attamyces specialization that tighten coevolution at the northern frontier; (ii) distributions of genetically identical Attamyces clones over large areas (up to 81 000 km2, approx. the area of Ireland, Austria or Panama); (iii) admixture rates between Attamyces lineages that appear lower in northern than in tropical populations; and (iv) long-distance gene flow of Attamyces across a dispersal barrier for leaf-cutter ants (ocean between mainland North America and Cuba). The latter suggests that Attamyces fungi may occasionally disperse independently of the ants, contrary to the traditional assumption that Attamyces fungi depend entirely on leaf-cutter queens for dispersal. Peripheral populations in Argentina or at mid-elevation sites in the Andes may reveal additional regional variants in ant–Attamyces coevolution. Studies of such populations are most likely to inform models of coextinctions of obligate mutualistic partners that are doubly stressed by habitat marginality and by environmental change. PMID:21389026

  10. Flammability Limits of Gases Under Low Gravity Conditions

    NASA Technical Reports Server (NTRS)

    Strehlow, R. A.

    1985-01-01

    The purpose of this combustion science investigation is to determine the effect of zero, fractional, and super gravity on the flammability limits of a premixed methane air flame in a standard 51 mm diameter flammability tube and to determine, if possible, the fluid flow associated with flame passage under zero-g conditions and the density (and hence, temperature) profiles associated with the flame under conditions of incipient extinction. This is accomplished by constructing an appropriate apparatus for placement in NASA's Lewis Research Center Lear Jet facility and flying the prescribed g-trajectories while the experiment is being performed. Data is recorded photographically using the visible light of the flame. The data acquired is: (1) the shape and propagation velocity of the flame under various g-conditions for methane compositions that are inside the flammable limits, and (2) the effect of gravity on the limits. Real time accelerometer readings for the three orthogonal directions are displayed in full view of the cameras and the framing rate of the cameras is used to measure velocities.

  11. Biological conversion of synthesis gas. Limiting conditions/scale-up

    SciTech Connect

    Basu, R.; Klasson, K.T.; Takriff, M.; Clausen, E.C.; Gaddy, J.L.

    1993-09-01

    The purpose of this research is to develop a technically and economically feasible process for biologically producing H(sub 2) from synthesis gas while, at the same time, removing harmful sulfur gas compounds. Six major tasks are being studied: 1. Culture development, where the best cultures are selected and conditions optimized for simultaneous hydrogen production and sulfur gas removal; 2. Mass transfer and kinetic studies in which equations necessary for process design are developed; 3. Bioreactor design studies, where the cultures chosen in Task 1 are utilized in continuous reaction vessels to demonstrate process feasibility and define operating conditions; 4. Evaluation of biological synthetic gas conversion under limiting conditions in preparation for industrial demonstration studies; 5. Process scale-up where laboratory data are scaled to larger-size units in preparation for process demonstration in a pilot-scale unit; and 6. Economic evaluation, where process simulations are used to project process economics and identify high cost areas during sensitivity analyses.

  12. Oxygen Consumption Rates of Bacteria under Nutrient-Limited Conditions

    PubMed Central

    Riedel, Timothy E.; Nealson, Kenneth H.; Finkel, Steven E.

    2013-01-01

    Many environments on Earth experience nutrient limitation and as a result have nongrowing or very slowly growing bacterial populations. To better understand bacterial respiration under environmentally relevant conditions, the effect of nutrient limitation on respiration rates of heterotrophic bacteria was measured. The oxygen consumption and population density of batch cultures of Escherichia coli K-12, Shewanella oneidensis MR-1, and Marinobacter aquaeolei VT8 were tracked for up to 200 days. The oxygen consumption per CFU (QO2) declined by more than 2 orders of magnitude for all three strains as they transitioned from nutrient-abundant log-phase growth to the nutrient-limited early stationary phase. The large reduction in QO2 from growth to stationary phase suggests that nutrient availability is an important factor in considering environmental respiration rates. Following the death phase, during the long-term stationary phase (LTSP), QO2 values of the surviving population increased with time and more cells were respiring than formed colonies. Within the respiring population, a subpopulation of highly respiring cells increased in abundance with time. Apparently, as cells enter LTSP, there is a viable but not culturable population whose bulk community and per cell respiration rates are dynamic. This result has a bearing on how minimal energy requirements are met, especially in nutrient-limited environments. The minimal QO2 rates support the extension of Kleiber's law to the mass of a bacterium (100-fg range). PMID:23770901

  13. [Biological mutualism, concepts and models].

    PubMed

    Perru, Olivier

    2011-01-01

    Mutualism is a biological association for a mutual benefit between two different species. In this paper, firstly, we examine the history and signification of mutualism in relation to symbiosis. Then, we consider the link between concepts and models of mutualism. Models of mutualism depend on different concepts we use: If mutualism is situated at populations' level, it will be expressed by Lotka-Volterra models, concerning exclusively populations' size. If mutualism is considered as a resources' exchange or a biological market increasing the fitness of these organisms, it will be described at an individual level by a cost-benefit model. Our analysis will be limited to the history and epistemology of Lotka-Volterra models and we hypothesize that these models are adapted at first to translate dynamic evolutions of mutualism. They render stability or variations of size and assume that there are clear distinctions and a state of equilibrium between populations of different species. Italian mathematician Vito Volterra demonstrated that biological associations consist in a constant relation between some species. In 1931 and 1935, Volterra described the general form of antagonistic or mutualistic biological associations by the same differential equations. We recognize that these equations have been more used to model competition or prey-predator interactions, but a simple sign change allows describing mutualism. The epistemological problem is the following: Volterra's equations help us to conceptualize a global phenomenon. However, mutualistic interactions may have stronger effects away from equilibrium and these effects may be better understood at individual level. We conclude that, between 1985 and 2000, some researchers carried on working and converting Lotka-Volterra models but this description appeared as insufficient. So, other researchers adopted an economical viewpoint, considering mutualism as a biological market.

  14. Amyloid Fibrillation of Insulin under Water-Limited Conditions

    PubMed Central

    Choi, Tae Su; Lee, Jong Wha; Jin, Kyeong Sik; Kim, Hugh I.

    2014-01-01

    Amyloid fibrillation in water-organic mixtures has been widely studied to understand the effect of protein-solvent interactions on the fibrillation process. In this study, we monitored insulin fibrillation in formamide and its methyl derivatives (formamide, N-methyl formamide, N,N-dimethyl formamide) in the presence and absence of water. These model solvent systems mimic the cellular environment by providing denaturing conditions and a hydrophobic environment with limited water content. Thioflavin T (ThT) assay revealed that binary mixtures of water with formamide and its methyl derivatives enhanced fibrillation rates and β-sheet abundance, whereas organic solvents suppressed insulin fibrillation. We utilized solution small-angle x-ray scattering (SAXS) and differential scanning calorimetry (DSC) to investigate the correlation between protein-solvent interactions and insulin fibrillation. SAXS experiments combined with simulated annealing of the protein indicated that the degree of denaturation of the hydrophobic core region at residues B11–B17 determines the fibrillation rate. In addition, DSC experiments suggested a crucial role of hydrophobic interactions in the fibrillation process. These results imply that an environment with limited water, which imitates a lipid membrane system, accelerates protein denaturation and the formation of intermolecular hydrophobic interactions during amyloid fibrillation. PMID:25418175

  15. Pesticides water decontamination in oxygen-limited conditions.

    PubMed

    Suciu, Nicoleta Alina; Ferrari, Federico; Vasileiadis, Sotirios; Merli, Annalisa; Capri, Ettore; Trevisan, Marco

    2013-01-01

    This study was undertaken to develop a laboratory bioreactor, with a functioning principle similar with that of biobed systems but working in oxygen-limited conditions, suitable for decontaminating wastewater mixtures with pesticides. The system is composed by two cylindrical plastic containers. The first one, where the pesticides solution is collected, is open, whereas the second one, where the biomass is disposed, is closed. The pesticides solution was pumped at the biomass surface and subsequently recollected and disposed in the first container. Four pesticides with different physical-chemical characteristics were tested. The results obtained showed a relatively good capacity of the developed prototype to decontaminate waste water containing the mixture of pesticides. The time of the experiment, the number of cycles that the solution made in the system and the environmental temperature have a significantly influence for the decontamination of acetochlor and chlorpyrifos whereas for the decontamination of terbuthylazine and metalaxyl no significant influence was observed. Even if the present prototype could represent a valid solution to manage the water pesticides residues in a farm and to increase the confidence of bystanders and residents, the practical difficulties when replacing the biomass could represent a limit of the system.

  16. Bacteriophages Limit the Existence Conditions for Conjugative Plasmids

    PubMed Central

    Wood, A. Jamie; Dytham, Calvin; Pitchford, Jonathan W.; Truman, Julie; Spiers, Andrew; Paterson, Steve; Brockhurst, Michael A.

    2015-01-01

    ABSTRACT Bacteriophages are a major cause of bacterial mortality and impose strong selection on natural bacterial populations, yet their effects on the dynamics of conjugative plasmids have rarely been tested. We combined experimental evolution, mathematical modeling, and individual-based simulations to explain how the ecological and population genetics effects of bacteriophages upon bacteria interact to determine the dynamics of conjugative plasmids and their persistence. The ecological effects of bacteriophages on bacteria are predicted to limit the existence conditions for conjugative plasmids, preventing persistence under weak selection for plasmid accessory traits. Experiments showed that phages drove faster extinction of plasmids in environments where the plasmid conferred no benefit, but they also revealed more complex effects of phages on plasmid dynamics under these conditions, specifically, the temporary maintenance of plasmids at fixation followed by rapid loss. We hypothesized that the population genetic effects of bacteriophages, specifically, selection for phage resistance mutations, may have caused this. Further mathematical modeling and individual-based simulations supported our hypothesis, showing that conjugative plasmids may hitchhike with phage resistance mutations in the bacterial chromosome. PMID:26037122

  17. First-wall and limiter conditioning in TFTR

    SciTech Connect

    Dylla, H.F.; Blanchard, W.R.; Hawryluk, R.J.; Hill, K.W.; Krawchuk, R.B.; Mueller, D.; Owens, D.K.; Ramsey, A.T.; Sesnic, S.; Tenney, F.H.

    1984-10-01

    A progress report on the experimental studies of vacuum vessel conditioning during the first year of TFTR operation is presented. A previous paper described the efforts expended to condition the TFTR vessel prior to and during the initial plasma start-up experiments. During the start-up phase, discharge cleaning was performed with the vessel at room temperature. For the second phase of TFTR operations, which was directed towards the optimization of ohmically heated plasmas, the vacuum vessel could be heated to 150/sup 0/C. The internal configuration of the TFTR vessel was more complex during the second phase with the addition of a TiC/C moveable limiter array, Inconel bellows cover plates, and ZrAl getter pumps. A quantitative comparison is given on the effectiveness of vessel bakeout, glow discharge cleaning, and pulse discharge cleaning in terms of the total quantity of removed carbon and oxygen, residual gas base pressures and the resulting plasma impurity levels as measured by visible, uv, and soft x-ray spectroscopy. The initial experience with hydrogen isotope changeover in TFTR is presented including the results of the attempt to hasten the changeover time by using a glow discharge to precondition the vessel with the new isotope.

  18. 29 CFR Appendix A to Subpart Y of... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions A Appendix A to Subpart Y of Part 1926 Labor Regulations Relating to Labor... of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions Note: The...

  19. Modeling of rhythmic behavior in neutral lipid production due to continuous supply of limited nitrogen: mutual growth and lipid accumulation in microalgae.

    PubMed

    Tevatia, Rahul; Allen, James; Blum, Paul; Demirel, Yaşar; Black, Paul

    2014-10-01

    The relative effects of three precise nitrogen limitation regimes on green micro-algae were assessed using the Trebouxiophycean alga Coccomyxa subellipsoidea grown in a chemostatic bioreactor system. The data provides further evidence that growth and triglyceride (TAG) accumulation are concurrent and independently proportional to the degree of nitrogen limitation in algae. Additionally, TAG accumulation was observed to proceed via oscillations with respect to time and percent dry weight quantity. The predator-prey model was applied to fit the experimental data and to obtain the physiological significance of these oscillations. The results determine the conditions of maximum neutral lipid productivity with respect to nitrate stress and highlight an area of potential future research.

  20. Conditions for diffusion-limited and reaction-limited recombination in nanostructured solar cells

    SciTech Connect

    Ansari-Rad, Mehdi; Anta, Juan A.; Arzi, Ezatollah

    2014-04-07

    The performance of Dye-sensitized solar cells (DSC) and related devices made of nanostructured semiconductors relies on a good charge separation, which in turn is achieved by favoring charge transport against recombination. Although both processes occur at very different time scales, hence ensuring good charge separation, in certain cases the kinetics of transport and recombination can be connected, either in a direct or an indirect way. In this work, the connection between electron transport and recombination in nanostructured solar cells is studied both theoretically and by Monte Carlo simulation. Calculations using the Multiple-Trapping model and a realistic trap distribution for nanostructured TiO{sub 2} show that for attempt-to-jump frequencies higher than 10{sup 11}–10{sup 13} Hz, the system adopts a reaction limited (RL) regime, with a lifetime which is effectively independent from the speed of the electrons in the transport level. For frequencies lower than those, and depending on the concentration of recombination centers in the material, the system enters a diffusion-limited regime (DL), where the lifetime increases if the speed of free electrons decreases. In general, the conditions for RL or DL recombination depend critically on the time scale difference between recombination kinetics and free-electron transport. Hence, if the former is too rapid with respect to the latter, the system is in the DL regime and total thermalization of carriers is not possible. In the opposite situation, a RL regime arises. Numerical data available in the literature, and the behavior of the lifetime with respect to (1) density of recombination centers and (2) probability of recombination at a given center, suggest that a typical DSC in operation stays in the RL regime with complete thermalization, although a transition to the DL regime may occur for electrolytes or hole conductors where recombination is especially rapid or where there is a larger dispersion of energies of

  1. Conditions for diffusion-limited and reaction-limited recombination in nanostructured solar cells

    NASA Astrophysics Data System (ADS)

    Ansari-Rad, Mehdi; Anta, Juan A.; Arzi, Ezatollah

    2014-04-01

    The performance of Dye-sensitized solar cells (DSC) and related devices made of nanostructured semiconductors relies on a good charge separation, which in turn is achieved by favoring charge transport against recombination. Although both processes occur at very different time scales, hence ensuring good charge separation, in certain cases the kinetics of transport and recombination can be connected, either in a direct or an indirect way. In this work, the connection between electron transport and recombination in nanostructured solar cells is studied both theoretically and by Monte Carlo simulation. Calculations using the Multiple-Trapping model and a realistic trap distribution for nanostructured TiO2 show that for attempt-to-jump frequencies higher than 1011-1013 Hz, the system adopts a reaction limited (RL) regime, with a lifetime which is effectively independent from the speed of the electrons in the transport level. For frequencies lower than those, and depending on the concentration of recombination centers in the material, the system enters a diffusion-limited regime (DL), where the lifetime increases if the speed of free electrons decreases. In general, the conditions for RL or DL recombination depend critically on the time scale difference between recombination kinetics and free-electron transport. Hence, if the former is too rapid with respect to the latter, the system is in the DL regime and total thermalization of carriers is not possible. In the opposite situation, a RL regime arises. Numerical data available in the literature, and the behavior of the lifetime with respect to (1) density of recombination centers and (2) probability of recombination at a given center, suggest that a typical DSC in operation stays in the RL regime with complete thermalization, although a transition to the DL regime may occur for electrolytes or hole conductors where recombination is especially rapid or where there is a larger dispersion of energies of electron acceptors.

  2. 43 CFR 2741.7 - Acreage limitations and general conditions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... extent that the conveyances would not have exceeded the limitations of said year. (c) No patents shall be issued under the act unless and until the public lands are officially surveyed. This requirement does...

  3. 43 CFR 2741.7 - Acreage limitations and general conditions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... extent that the conveyances would not have exceeded the limitations of said year. (c) No patents shall be issued under the act unless and until the public lands are officially surveyed. This requirement does...

  4. 43 CFR 2741.7 - Acreage limitations and general conditions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... extent that the conveyances would not have exceeded the limitations of said year. (c) No patents shall be issued under the act unless and until the public lands are officially surveyed. This requirement does...

  5. Plant invasions--the role of mutualisms.

    PubMed

    Richardson, D M; Allsopp, N; D'Antonio, C M; Milton, S J; Rejmánek, M

    2000-02-01

    Many introduced plant species rely on mutualisms in their new habitats to overcome barriers to establishment and to become naturalized and, in some cases, invasive. Mutualisms involving animal-mediated pollination and seed dispersal, and symbioses between plant roots and microbiota often facilitate invasions. The spread of many alien plants, particularly woody ones, depends on pollinator mutualisms. Most alien plants are well served by generalist pollinators (insects and birds), and pollinator limitation does not appear to be a major barrier for the spread of introduced plants (special conditions relating to Ficus and orchids are described). Seeds of many of the most notorious plant invaders are dispersed by animals, mainly birds and mammals. Our review supports the view that tightly coevolved, plant-vertebrate seed dispersal systems are extremely rare. Vertebrate-dispersed plants are generally not limited reproductively by the lack of dispersers. Most mycorrhizal plants form associations with arbuscular mycorrhizal fungi which, because of their low specificity, do not seem to play a major role in facilitating or hindering plant invasions (except possibly on remote islands such as the Galapagos which are poor in arbuscular mycorrhizal fungi). The lack of symbionts has, however, been a major barrier for many ectomycorrhizal plants, notably for Pinus spp. in parts of the southern hemisphere. The roles of nitrogen-fixing associations between legumes and rhizobia and between actinorhizal plants and Frankia spp. in promoting or hindering invasions have been virtually ignored in the invasions literature. Symbionts required to induce nitrogen fixation in many plants are extremely widespread, but intentional introductions of symbionts have altered the invasibility of many, if not most, systems. Some of the world's worst invasive alien species only invaded after the introduction of symbionts. Mutualisms in the new environment sometimes re-unite the same species that form

  6. 14 CFR 135.227 - Icing conditions: Operating limitations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... limitations. Link to an amendment published at 74 FR 62696, Dec. 1, 2009. (a) No pilot may take off an... authorized by the Administrator. (b) No certificate holder may authorize an airplane to take off and no pilot... expected to adhere to the airplane unless the pilot has completed all applicable training as required...

  7. Biological effects of extreme environmental conditions. [considering limits of biosphere

    NASA Technical Reports Server (NTRS)

    Imshenetskiy, A. A.

    1975-01-01

    Actions of extreme physical and chemical space factors on microorganisms and plants are elaborated in order to establish limits for the biosphere. Considered are effects of low and high temperatures; ionizing and ultraviolet radiation; various gases; and effects of vibration, desiccation and acceleration.

  8. Advances and limitations of visual conditioning protocols in harnessed bees.

    PubMed

    Avarguès-Weber, Aurore; Mota, Theo

    2016-12-18

    Bees are excellent invertebrate models for studying visual learning and memory mechanisms, because of their sophisticated visual system and impressive cognitive capacities associated with a relatively simple brain. Visual learning in free-flying bees has been traditionally studied using an operant conditioning paradigm. This well-established protocol, however, can hardly be combined with invasive procedures for studying the neurobiological basis of visual learning. Different efforts have been made to develop protocols in which harnessed honey bees could associate visual cues with reinforcement, though learning performances remain poorer than those obtained with free-flying animals. Especially in the last decade, the intention of improving visual learning performances of harnessed bees led many authors to adopt distinct visual conditioning protocols, altering parameters like harnessing method, nature and duration of visual stimulation, number of trials, inter-trial intervals, among others. As a result, the literature provides data hardly comparable and sometimes contradictory. In the present review, we provide an extensive analysis of the literature available on visual conditioning of harnessed bees, with special emphasis on the comparison of diverse conditioning parameters adopted by different authors. Together with this comparative overview, we discuss how these diverse conditioning parameters could modulate visual learning performances of harnessed bees.

  9. The Limits of Knowledge Management in Contemporary Corporate Conditions

    ERIC Educational Resources Information Center

    Garrick, John

    2014-01-01

    This paper draws on Jean-François Lyotard's (1984) seminal study "The Postmodern Condition: A Report on Knowledge" to reflect on two macro-level catastrophes: the global financial crisis (GFC) of 2009 (and its continuing effects throughout the Eurozone and elsewhere) and Fukushima. These two case studies probe aspects of these grand…

  10. 14 CFR 125.221 - Icing conditions: Operating limitations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 74 FR 62696, Dec. 1, 2009. (a) No pilot may take off an airplane that has frost, ice, or snow... authorize an airplane to take off and no pilot may take off an airplane any time conditions are such that frost, ice, or snow may reasonably be expected to adhere to the airplane unless the pilot has...

  11. 33 CFR 330.4 - Conditions, limitations, and restrictions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... with any existing or proposed Federal project. (c) State 401 water quality certification. (1) State 401 water quality certification pursuant to section 401 of the Clean Water Act, or waiver thereof, is... issues a 401 water quality certification which includes special conditions, the division engineer...

  12. 33 CFR 330.4 - Conditions, limitations, and restrictions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... issues a 401 water quality certification which includes special conditions, the division engineer will... without prejudice until the state issues an individual 401 water quality certification or waives its right... state action on the individual section 401 water quality certification. If a state issues a...

  13. Covariant mutually unbiased bases

    NASA Astrophysics Data System (ADS)

    Carmeli, Claudio; Schultz, Jussi; Toigo, Alessandro

    2016-06-01

    The connection between maximal sets of mutually unbiased bases (MUBs) in a prime-power dimensional Hilbert space and finite phase-space geometries is well known. In this article, we classify MUBs according to their degree of covariance with respect to the natural symmetries of a finite phase-space, which are the group of its affine symplectic transformations. We prove that there exist maximal sets of MUBs that are covariant with respect to the full group only in odd prime-power dimensional spaces, and in this case, their equivalence class is actually unique. Despite this limitation, we show that in dimension 2r covariance can still be achieved by restricting to proper subgroups of the symplectic group, that constitute the finite analogues of the oscillator group. For these subgroups, we explicitly construct the unitary operators yielding the covariance.

  14. Construction of bacteria-eukaryote synthetic mutualism.

    PubMed

    Kubo, Isao; Hosoda, Kazufumi; Suzuki, Shingo; Yamamoto, Kayo; Kihara, Kumiko; Mori, Kotaro; Yomo, Tetsuya

    2013-08-01

    Mutualism is ubiquitous in nature but is known to be intrinsically vulnerable with regard to both population dynamics and evolution. Synthetic ecology has indicated that it is feasible for organisms to establish novel mutualism merely through encountering each other by showing that it is feasible to construct synthetic mutualism between organisms. However, bacteria-eukaryote mutualism, which is ecologically important, has not yet been constructed. In this study, we synthetically constructed mutualism between a bacterium and a eukaryote by using two model organisms. We mixed a bacterium, Escherichia coli (a genetically engineered glutamine auxotroph), and an amoeba, Dictyostelium discoideum, in 14 sets of conditions in which each species could not grow in monoculture but potentially could grow in coculture. Under a single condition in which the bacterium and amoeba mutually compensated for the lack of required nutrients (lipoic acid and glutamine, respectively), both species grew continuously through several subcultures, essentially establishing mutualism. Our results shed light on the establishment of bacteria-eukaryote mutualism and indicate that a bacterium and eukaryote pair in nature also has a non-negligible possibility of establishing novel mutualism if the organisms are potentially mutualistic.

  15. 29 CFR Appendix A to Subpart Y of... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions A Appendix A to Subpart Y of Part 1926 Labor Regulations Relating to Labor... REGULATIONS FOR CONSTRUCTION Diving Pt. 1926, Subpt. Y, App. A Appendix A to Subpart Y of Part...

  16. 29 CFR Appendix A to Subpart Y of... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions A Appendix A to Subpart Y of Part 1926 Labor Regulations Relating to Labor... REGULATIONS FOR CONSTRUCTION Diving Pt. 1926, Subpt. Y, App. A Appendix A to Subpart Y of Part...

  17. 29 CFR Appendix A to Subpart Y of... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions A Appendix A to Subpart Y of Part 1926 Labor Regulations Relating to Labor... REGULATIONS FOR CONSTRUCTION Diving Pt. 1926, Subpt. Y, App. A Appendix A to Subpart Y of Part...

  18. 29 CFR Appendix A to Subpart Y of... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions A Appendix A to Subpart Y of Part 1926 Labor Regulations Relating to Labor... REGULATIONS FOR CONSTRUCTION Diving Pt. 1926, Subpt. Y, App. A Appendix A to Subpart Y of Part...

  19. What Conditions Limit Sports Participation? Experience with 10,540 Athletes.

    ERIC Educational Resources Information Center

    Magnes, Scott A.; And Others

    1992-01-01

    Researchers evaluated results from five years of preseason examinations on student athletes to determine which conditions limited sports participation. Hypertension, ophthalmologic and genitourinary abnormalities, and musculoskeletal problems were the most common limiting conditions. Preseason examinations need to follow guidelines based on…

  20. 50 CFR 22.32 - Conditions and limitations on taking under depredation control order.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Golden Eagles § 22.32 Conditions and limitations on taking under depredation control order. (a) Whenever... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Conditions and limitations on taking under depredation control order. 22.32 Section 22.32 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE...

  1. Mutually Exclusive Uncertainty Relations

    NASA Astrophysics Data System (ADS)

    Xiao, Yunlong; Jing, Naihuan

    2016-11-01

    The uncertainty principle is one of the characteristic properties of quantum theory based on incompatibility. Apart from the incompatible relation of quantum states, mutually exclusiveness is another remarkable phenomenon in the information- theoretic foundation of quantum theory. We investigate the role of mutual exclusive physical states in the recent work of stronger uncertainty relations for all incompatible observables by Mccone and Pati and generalize the weighted uncertainty relation to the product form as well as their multi-observable analogues. The new bounds capture both incompatibility and mutually exclusiveness, and are tighter compared with the existing bounds.

  2. Mutually Exclusive Uncertainty Relations.

    PubMed

    Xiao, Yunlong; Jing, Naihuan

    2016-11-08

    The uncertainty principle is one of the characteristic properties of quantum theory based on incompatibility. Apart from the incompatible relation of quantum states, mutually exclusiveness is another remarkable phenomenon in the information- theoretic foundation of quantum theory. We investigate the role of mutual exclusive physical states in the recent work of stronger uncertainty relations for all incompatible observables by Mccone and Pati and generalize the weighted uncertainty relation to the product form as well as their multi-observable analogues. The new bounds capture both incompatibility and mutually exclusiveness, and are tighter compared with the existing bounds.

  3. Mutually Exclusive Uncertainty Relations

    PubMed Central

    Xiao, Yunlong; Jing, Naihuan

    2016-01-01

    The uncertainty principle is one of the characteristic properties of quantum theory based on incompatibility. Apart from the incompatible relation of quantum states, mutually exclusiveness is another remarkable phenomenon in the information- theoretic foundation of quantum theory. We investigate the role of mutual exclusive physical states in the recent work of stronger uncertainty relations for all incompatible observables by Mccone and Pati and generalize the weighted uncertainty relation to the product form as well as their multi-observable analogues. The new bounds capture both incompatibility and mutually exclusiveness, and are tighter compared with the existing bounds. PMID:27824161

  4. Evolution of mutualism between species

    SciTech Connect

    Post, W.M.; Travis, C.C.; DeAngelis, D.L.

    1980-01-01

    Recent theoretical work on mutualism, the interaction between species populations that is mutually beneficial, is reviewed. Several ecological facts that should be addressed in the construction of dynamic models for mutualism are examined. Basic terminology is clarified. (PSB)

  5. Phase stability limit of c-BN under hydrostatic and non-hydrostatic pressure conditions

    SciTech Connect

    Xiao, Jianwei; Du, Jinglian; Wen, Bin Zhang, Xiangyi; Melnik, Roderick; Kawazoe, Yoshiyuki

    2014-04-28

    Phase stability limit of cubic boron nitride (c-BN) has been investigated by the crystal structure search technique. It indicated that this limit is ∼1000 GPa at hydrostatic pressure condition. Above this pressure, c-BN turns into a metastable phase with respect to rocksalt type boron nitride (rs-BN). However, rs-BN cannot be retained at 0 GPa owing to its instability at pressure below 250 GPa. For non-hydrostatic pressure conditions, the phase stability limit of c-BN is substantially lower than that under hydrostatic pressure conditions and it is also dramatically different for other pressure mode.

  6. The financial repercussions of new work-limiting health conditions for older workers.

    PubMed

    Schimmel, Jody; Stapleton, David C

    2012-01-01

    This analysis used propensity score matching to construct a comparison sample that is observationally similar at baseline interview to older workers who later experience the onset of a medical condition that limits their ability to work. Using these matched onset and comparison samples, we studied trajectories in earnings and income around onset of the work limitation. Earnings two years after onset for the work-limitation group were 50% lower and poverty rates were nearly double. Income from unemployment insurance, workers' compensation, and retirement and disability benefits offset only a small amount of the earnings declines, resulting in decreased overall household income after onset of the work-limiting condition.

  7. Justification of Filter Selection for Robot Balancing in Conditions of Limited Computational Resources

    NASA Astrophysics Data System (ADS)

    Momot, M. V.; Politsinskaia, E. V.; Sushko, A. V.; Semerenko, I. A.

    2016-08-01

    The paper considers the problem of mathematical filter selection, used for balancing of wheeled robot in conditions of limited computational resources. The solution based on complementary filter is proposed.

  8. Pontine Stimulation Overcomes Developmental Limitations in the Neural Mechanisms of Eyeblink Conditioning

    ERIC Educational Resources Information Center

    Freeman, John H., Jr; Rabinak, Christine A.; Campolattaro, Matthew M.

    2005-01-01

    Pontine neuronal activation during auditory stimuli increases ontogenetically between postnatal days (P) P17 and P24 in rats. Pontine neurons are an essential component of the conditioned stimulus (CS) pathway for eyeblink conditioning, providing mossy fiber input to the cerebellum. Here we examined whether the developmental limitation in pontine…

  9. 42 CFR 410.39 - Prostate cancer screening tests: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 2 2012-10-01 2012-10-01 false Prostate cancer screening tests: Conditions for and... Medical and Other Health Services § 410.39 Prostate cancer screening tests: Conditions for and limitations... cancer screening tests means any of the following procedures furnished to an individual for the...

  10. 42 CFR 410.39 - Prostate cancer screening tests: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Prostate cancer screening tests: Conditions for and... Medical and Other Health Services § 410.39 Prostate cancer screening tests: Conditions for and limitations... cancer screening tests means any of the following procedures furnished to an individual for the...

  11. 42 CFR 410.39 - Prostate cancer screening tests: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false Prostate cancer screening tests: Conditions for and... Medical and Other Health Services § 410.39 Prostate cancer screening tests: Conditions for and limitations... cancer screening tests means any of the following procedures furnished to an individual for the...

  12. 42 CFR 410.39 - Prostate cancer screening tests: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Prostate cancer screening tests: Conditions for and... Medical and Other Health Services § 410.39 Prostate cancer screening tests: Conditions for and limitations... cancer screening tests means any of the following procedures furnished to an individual for the...

  13. 42 CFR 410.39 - Prostate cancer screening tests: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Prostate cancer screening tests: Conditions for and... Medical and Other Health Services § 410.39 Prostate cancer screening tests: Conditions for and limitations... cancer screening tests means any of the following procedures furnished to an individual for the...

  14. 34 CFR 675.20 - Eligible employers and general conditions and limitation on employment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Education (Continued) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION FEDERAL WORK-STUDY PROGRAMS Federal Work-Study Program § 675.20 Eligible employers and general conditions and limitation on employment... agreement with that agency or organization. The agreement must set forth the FWS work conditions....

  15. Mutually Exclusive, Complementary, or . . .

    ERIC Educational Resources Information Center

    Schloemer, Cathy G.

    2016-01-01

    Whether students are beginning their study of probability or are well into it, distinctions between complementary sets and mutually exclusive sets can be confusing. Cathy Schloemer writes in this article that for years she used typical classroom examples but was not happy with the student engagement or the level of understanding they produced.…

  16. Mutual Adaptaion in Action

    ERIC Educational Resources Information Center

    Siskin, Leslie Santee

    2016-01-01

    Building on an expanded concept of mutual adaptation, this chapter explores a distinctive and successful aspect of International Baccalaureate's effort to scale up, as they moved to expand their programs and support services in Title I schools. Based on a three-year, mixed-methods study, it offers a case where we see not only local adaptations…

  17. Reducing Conservatism in Aircraft Engine Response Using Conditionally Active Min-Max Limit Regulators

    NASA Technical Reports Server (NTRS)

    May, Ryan D.; Garg, Sanjay

    2012-01-01

    Current aircraft engine control logic uses a Min-Max control selection structure to prevent the engine from exceeding any safety or operational limits during transients due to throttle commands. This structure is inherently conservative and produces transient responses that are slower than necessary. In order to utilize the existing safety margins more effectively, a modification to this architecture is proposed, referred to as a Conditionally Active (CA) limit regulator. This concept uses the existing Min-Max architecture with the modification that limit regulators are active only when the operating point is close to a particular limit. This paper explores the use of CA limit regulators using a publicly available commercial aircraft engine simulation. The improvement in thrust response while maintaining all necessary safety limits is demonstrated in a number of cases.

  18. Phenological shifts and the fate of mutualisms

    PubMed Central

    Rafferty, Nicole E.; CaraDonna, Paul J.; Bronstein, Judith L.

    2014-01-01

    Climate change is altering the timing of life history events in a wide array of species, many of which are involved in mutualistic interactions. Because many mutualisms can form only if partner species are able to locate each other in time, differential phenological shifts are likely to influence their strength, duration and outcome. At the extreme, climate change-driven shifts in phenology may result in phenological mismatch: the partial or complete loss of temporal overlap of mutualistic species. We have a growing understanding of how, when, and why phenological change can alter one type of mutualism–pollination. However, as we show here, there has been a surprising lack of attention to other types of mutualism. We generate a set of predictions about the characteristics that may predispose mutualisms in general to phenological mismatches. We focus not on the consequences of such mismatches but rather on the likelihood that mismatches will develop. We explore the influence of three key characteristics of mutualism: 1) intimacy, 2) seasonality and duration, and 3) obligacy and specificity. We predict that the following characteristics of mutualism may increase the likelihood of phenological mismatch: 1) a non-symbiotic life history in which co-dispersal is absent; 2) brief, seasonal interactions; and 3) facultative, generalized interactions. We then review the limited available data in light of our a priori predictions and point to mutualisms that are more and less likely to be at risk of becoming phenologically mismatched, emphasizing the need for research on mutualisms other than plant–pollinator interactions. Future studies should explicitly focus on mutualism characteristics to determine whether and how changing phenologies will affect mutualistic interactions. PMID:25883391

  19. Model-based condition monitoring of PEM fuel cell using Hotelling T 2 control limit

    NASA Astrophysics Data System (ADS)

    Xue, X.; Tang, J.; Sammes, N.; Ding, Y.

    Although a variety of design and control strategies have been proposed to improve the performance of polymer electrolyte membrane (PEM) fuel cell systems, temporary faults in such systems still might occur during operations due to the complexity of the physical process and the functional limitations of some components. The development of an effective condition monitoring system that can detect these faults in a timely manner is complicated by the operating condition variation, the significant variability/uncertainty of the fuel cell system, and the measurement noise. In this research, we propose a model-based condition monitoring scheme that employs the Hotelling T 2 statistical analysis for fault detection of PEM fuel cells. Under a given operating condition, the instantaneous load current, the temperature and fuel/gas source pressures of the fuel cell are measured. These measurements are then fed into a lumped parameter dynamic fuel cell model for the establishment of the baseline under the same operating condition for comparison. The fuel cell operation is simulated under statistical sampling of parametric uncertainties with specified statistics (mean and variance) that account for the system variability/uncertainty and measurement noise. This yields a group of output voltages (under the same operating condition but with uncertainties) as the baseline. Fault detection is facilitated by comparing the real-time measurement of the fuel cell output voltage with the baseline voltages by employing the Hotelling T 2 statistical analysis. The baseline voltages are used to evaluate the output T 2 statistics under normal operating condition. Then, with a given confidence level the upper control limit can be specified. Fault condition will be declared if the T 2 statistics of real-time voltage measurement exceeds the upper control limit. This model-based robust condition monitoring scheme can deal with the operating condition variation, various uncertainties in a fuel cell

  20. Part mutual information for quantifying direct associations in networks.

    PubMed

    Zhao, Juan; Zhou, Yiwei; Zhang, Xiujun; Chen, Luonan

    2016-05-03

    Quantitatively identifying direct dependencies between variables is an important task in data analysis, in particular for reconstructing various types of networks and causal relations in science and engineering. One of the most widely used criteria is partial correlation, but it can only measure linearly direct association and miss nonlinear associations. However, based on conditional independence, conditional mutual information (CMI) is able to quantify nonlinearly direct relationships among variables from the observed data, superior to linear measures, but suffers from a serious problem of underestimation, in particular for those variables with tight associations in a network, which severely limits its applications. In this work, we propose a new concept, "partial independence," with a new measure, "part mutual information" (PMI), which not only can overcome the problem of CMI but also retains the quantification properties of both mutual information (MI) and CMI. Specifically, we first defined PMI to measure nonlinearly direct dependencies between variables and then derived its relations with MI and CMI. Finally, we used a number of simulated data as benchmark examples to numerically demonstrate PMI features and further real gene expression data from Escherichia coli and yeast to reconstruct gene regulatory networks, which all validated the advantages of PMI for accurately quantifying nonlinearly direct associations in networks.

  1. 26 CFR 1.831-3 - Tax on insurance companies (other than life or mutual), mutual marine insurance companies, mutual...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... mutual), mutual marine insurance companies, mutual fire insurance companies issuing perpetual policies... Companies § 1.831-3 Tax on insurance companies (other than life or mutual), mutual marine insurance... insurance business within the United States, and all mutual marine insurance companies and mutual fire...

  2. Limiter

    DOEpatents

    Cohen, S.A.; Hosea, J.C.; Timberlake, J.R.

    1984-10-19

    A limiter with a specially contoured front face is provided. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution. This limiter shape accommodates the various power scrape-off distances lambda p, which depend on the parallel velocity, V/sub parallel/, of the impacting particles.

  3. Prediction of sand transport over immobile gravel from supply limited to capacity conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prediction of the transport of sand in channels armored with gravel downstream of dams is difficult but necessary for the range of bed conditions from supply limited to capacity transport. Previous work has shown that information on the mean elevation of the sand relative to the gravel and on the s...

  4. Bacillus spp. from rainforest soil promote plant growth under limited nitrogen conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aims: The aim of this study was to evaluate effects of PGPR (Plant Growth Promoting Rhizobacteria) isolated from rainforest on different plants under limited nitrogen conditions. Methods and Results: Bacterial isolates from a Peruvian rainforest soil were screened for plant growth promoting effects...

  5. 78 FR 6273 - Public Use Limit on Commercial Dog Walking; Revised Disposal Conditions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-30

    ... From the Federal Register Online via the Government Publishing Office THE PRESIDIO TRUST 36 CFR Part 1002 Public Use Limit on Commercial Dog Walking; Revised Disposal Conditions AGENCY: The Presidio... consideration, shall remove pet excrement and deposit it in refuse containers. DATES: The comment period for...

  6. 77 FR 69785 - Public Use Limit on Commercial Dog Walking; Revised Disposal Conditions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-21

    ... Part 1002 Public Use Limit on Commercial Dog Walking; Revised Disposal Conditions AGENCY: The Presidio... consideration, shall remove pet excrement and deposit it in refuse containers. The Trust invites comments on the... requirement throughout Area B that pet excrement be removed and deposited in refuse containers. 1....

  7. 29 CFR 2590.701-3 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... diabetes, generally not subject to any lifetime dollar limit. However, if an individual was diagnosed with diabetes before the effective date of coverage under the plan, diabetes coverage is subject to a lifetime... imposed by Employer U's plan, has diabetes, as well as retinal degeneration, a foot condition, and...

  8. 50 CFR 22.32 - Conditions and limitations on taking under depredation control order.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... depredation control order. 22.32 Section 22.32 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... Golden Eagles § 22.32 Conditions and limitations on taking under depredation control order. (a) Whenever the taking of golden eagles without a permit is authorized for the seasonal protection of...

  9. 50 CFR 22.32 - Conditions and limitations on taking under depredation control order.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... depredation control order. 22.32 Section 22.32 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... Golden Eagles § 22.32 Conditions and limitations on taking under depredation control order. (a) Whenever the taking of golden eagles without a permit is authorized for the seasonal protection of...

  10. 50 CFR 22.32 - Conditions and limitations on taking under depredation control order.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... depredation control order. 22.32 Section 22.32 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... Golden Eagles § 22.32 Conditions and limitations on taking under depredation control order. (a) Whenever the taking of golden eagles without a permit is authorized for the seasonal protection of...

  11. 50 CFR 22.32 - Conditions and limitations on taking under depredation control order.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... depredation control order. 22.32 Section 22.32 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... Golden Eagles § 22.32 Conditions and limitations on taking under depredation control order. (a) Whenever the taking of golden eagles without a permit is authorized for the seasonal protection of...

  12. Limiter

    DOEpatents

    Cohen, Samuel A.; Hosea, Joel C.; Timberlake, John R.

    1986-01-01

    A limiter with a specially contoured front face accommodates the various power scrape-off distances .lambda..sub.p, which depend on the parallel velocity, V.sub..parallel., of the impacting particles. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution.

  13. Forming Limits in Sheet Metal Forming for Non-Proportional Loading Conditions - Experimental and Theoretical Approach

    SciTech Connect

    Ofenheimer, Aldo; Buchmayr, Bruno; Kolleck, Ralf

    2005-08-05

    The influence of strain paths (loading history) on material formability is well known in sheet forming processes. Sophisticated experimental methods are used to determine the entire shape of strain paths of forming limits for aluminum AA6016-T4 alloy. Forming limits for sheet metal in as-received condition as well as for different pre-deformation are presented. A theoretical approach based on Arrieux's intrinsic Forming Limit Stress Curve (FLSC) concept is employed to numerically predict the influence of loading history on forming severity. The detailed experimental strain paths are used in the theoretical study instead of any linear or bilinear simplified loading histories to demonstrate the predictive quality of forming limits in the state of stress.

  14. Computing cellular automata spectra under fixed boundary conditions via limit graphs

    NASA Astrophysics Data System (ADS)

    Ruivo, Eurico L. P.; de Oliveira, Pedro P. B.

    2016-01-01

    Cellular automata are fully discrete complex systems with parallel and homogeneous behavior studied both from the theoretical and modeling viewpoints. The limit behaviors of such systems are of particular interest, as they give insight into their emerging properties. One possible approach to investigate such limit behaviors is the analysis of the growth of graphs describing the finite time behavior of a rule in order to infer its limit behavior. Another possibility is to study the Fourier spectrum describing the average limit configurations obtained by a rule. While the former approach gives the characterization of the limit configurations of a rule, the latter yields a qualitative and quantitative characterisation of how often particular blocks of states are present in these limit configurations. Since both approaches are closely related, it is tempting to use one to obtain information about the other. Here, limit graphs are automatically adjusted by configurations directly generated by their respective rules, and use the graphs to compute the spectra of their rules. We rely on a set of elementary cellular automata rules, on lattices with fixed boundary condition, and show that our approach is a more reliable alternative to a previously described method from the literature.

  15. Growth of Geobacter sulfurreducens under nutrient-limiting conditions in continuous culture.

    PubMed

    Esteve-Núñez, Abraham; Rothermich, Mary; Sharma, Manju; Lovley, Derek

    2005-05-01

    A system for growing Geobacter sulfurreducens under anaerobic conditions in chemostats was developed in order to study the physiology of this organism under conditions that might more closely approximate those found in the subsurface than batch cultures. Geobacter sulfurreducens could be cultured under acetate-limiting conditions with fumarate or Fe(III)-citrate as the electron acceptor at growth rates between 0.04 and 0.09 h(-1). The molar growth yield was threefold higher with fumarate as the electron acceptor than with Fe(III), despite the lower mid-point potential of the fumarate/succinate redox couple. When growth was limited by availability of fumarate, high steady-state concentrations were detected, suggesting that fumarate is unlikely to be an important electron acceptor in sedimentary environments. The half-saturation constant, Ks, for acetate in Fe(III)-grown cultures (10 microM) suggested that the growth of Geobacter species is likely to be acetate limited in most subsurface sediments, but that when millimolar quantities of acetate are added to the subsurface in order to promote the growth of Geobacter for bioremediation applications, this should be enough to overcome any acetate limitations. When the availability of electron acceptors, rather than acetate, limited growth, G. sulfurreducens was less efficient in incorporating acetate into biomass but had higher respiration rates, a desirable physiological characteristic when adding acetate to stimulate the activity of Geobacter species during in situ uranium bioremediation. These results demonstrate that the ability to study the growth of G. sulfurreducens under steady-state conditions can provide insights into its physiological characteristics that have relevance for its activity in a diversity of sedimentary environments.

  16. {open_quotes}Hot-lab{close_quotes} experience on hydrometallurgical mutual separation and conditioning of three-valence transplutonium and rare earth elements

    SciTech Connect

    Renard, E.V.; Pavlovich, V.B.

    1996-12-31

    The paper contains results of {open_quotes}hot-lab{close_quotes} investigation experience of multistage liquid-liquid extraction and mixed (extraction-precipitation) operations of intergroup 3-valence transplutonides (TPE) and lanthanides (RE) separation using both modelling and real high active solutions produced in the process of fissile actinides recovery, i.e. high-level liquid waste (HLLW) of PUREX-technology. Extractive TPE-RE separation processes on the systems with acidic and amine extractants, inorganic salt-out agents, strong complex ones have been studied and modified. The presented real high activity products management results may be useful both in the {open_quotes}minor{close_quotes} actinides transmutation (chemical) technology and HLLW conditioning as well before vitrification on the stage of TPE removal and their separation from RE fission products.

  17. A water use and growth model for Eucalyptus plantation in water-limited conditions

    SciTech Connect

    Calder, I.R.

    1992-12-31

    To investigate the environmental impact of plantation forestry using fast-growing tree species in southern India, a program of field studies was initiated in 1987 specifically to measure the water use, nutrient uptake and growth rates of the plantations. A water use and growth (WAG) model is proposed for calculating transpiration and growth of Eucalyptus plantation in water-limited conditions. The model is based on the measured relationships between transpiration rate and basal cross-sectional area and soil moisture availability. The volume growth rate (in water-limited conditions) is assumed to be proportional to the volume of water transpired. The model is calibrated using (deuterium tracing) measurements of transpiration and measurements of growth recorded at the Puradal experimental plantation, Karnataka, southern India.

  18. Bayesian methodology to estimate and update safety performance functions under limited data conditions: a sensitivity analysis.

    PubMed

    Heydari, Shahram; Miranda-Moreno, Luis F; Lord, Dominique; Fu, Liping

    2014-03-01

    In road safety studies, decision makers must often cope with limited data conditions. In such circumstances, the maximum likelihood estimation (MLE), which relies on asymptotic theory, is unreliable and prone to bias. Moreover, it has been reported in the literature that (a) Bayesian estimates might be significantly biased when using non-informative prior distributions under limited data conditions, and that (b) the calibration of limited data is plausible when existing evidence in the form of proper priors is introduced into analyses. Although the Highway Safety Manual (2010) (HSM) and other research studies provide calibration and updating procedures, the data requirements can be very taxing. This paper presents a practical and sound Bayesian method to estimate and/or update safety performance function (SPF) parameters combining the information available from limited data with the SPF parameters reported in the HSM. The proposed Bayesian updating approach has the advantage of requiring fewer observations to get reliable estimates. This paper documents this procedure. The adopted technique is validated by conducting a sensitivity analysis through an extensive simulation study with 15 different models, which include various prior combinations. This sensitivity analysis contributes to our understanding of the comparative aspects of a large number of prior distributions. Furthermore, the proposed method contributes to unification of the Bayesian updating process for SPFs. The results demonstrate the accuracy of the developed methodology. Therefore, the suggested approach offers considerable promise as a methodological tool to estimate and/or update baseline SPFs and to evaluate the efficacy of road safety countermeasures under limited data conditions.

  19. Functional genomics analysis of free fatty acid production under continuous phosphate limiting conditions.

    PubMed

    Youngquist, J Tyler; Korosh, Travis C; Pfleger, Brian F

    2016-10-13

    Free fatty acids (FFA) are an attractive platform chemical that serves as a functional intermediate in metabolic pathways for producing oleochemicals. Many groups have established strains of Escherichia coli capable of producing various chain-length mixtures of FFA by heterologous expression of acyl-ACP thioesterases. For example, high levels of dodecanoic acid are produced by an E. coli strain expressing the Umbellularia californica FatB2 thioesterase, BTE. Prior studies achieved high dodecanoic acid yields and productivities under phosphate-limiting media conditions. In an effort to understand the metabolic and physiological changes that led to increased FFA production, the transcriptome of this strain was assessed as a function of nutrient limitation and growth rate. FFA generation under phosphate limitation led to consistent changes in transporter expression, osmoregulation, and central metabolism. Guided by these results, targeted knockouts led to a further ~11 % in yield in FFA.

  20. Role of microRNAs involved in plant response to nitrogen and phosphorous limiting conditions.

    PubMed

    Nguyen, Giao N; Rothstein, Steven J; Spangenberg, German; Kant, Surya

    2015-01-01

    Plant microRNAs (miRNAs) are a class of small non-coding RNAs which target and regulate the expression of genes involved in several growth, development, and metabolism processes. Recent researches have shown involvement of miRNAs in the regulation of uptake and utilization of nitrogen (N) and phosphorus (P) and more importantly for plant adaptation to N and P limitation conditions by modifications in plant growth, phenology, and architecture and production of secondary metabolites. Developing strategies that allow for the higher efficiency of using both N and P fertilizers in crop production is important for economic and environmental benefits. Improved crop varieties with better adaptation to N and P limiting conditions could be a key approach to achieve this effectively. Furthermore, understanding on the interactions between N and P uptake and use and their regulation is important for the maintenance of nutrient homeostasis in plants. This review describes the possible functions of different miRNAs and their cross-talk relevant to the plant adaptive responses to N and P limiting conditions. In addition, a comprehensive understanding of these processes at molecular level and importance of biological adaptation for improved N and P use efficiency is discussed.

  1. Role of microRNAs involved in plant response to nitrogen and phosphorous limiting conditions

    PubMed Central

    Nguyen, Giao N.; Rothstein, Steven J.; Spangenberg, German; Kant, Surya

    2015-01-01

    Plant microRNAs (miRNAs) are a class of small non-coding RNAs which target and regulate the expression of genes involved in several growth, development, and metabolism processes. Recent researches have shown involvement of miRNAs in the regulation of uptake and utilization of nitrogen (N) and phosphorus (P) and more importantly for plant adaptation to N and P limitation conditions by modifications in plant growth, phenology, and architecture and production of secondary metabolites. Developing strategies that allow for the higher efficiency of using both N and P fertilizers in crop production is important for economic and environmental benefits. Improved crop varieties with better adaptation to N and P limiting conditions could be a key approach to achieve this effectively. Furthermore, understanding on the interactions between N and P uptake and use and their regulation is important for the maintenance of nutrient homeostasis in plants. This review describes the possible functions of different miRNAs and their cross-talk relevant to the plant adaptive responses to N and P limiting conditions. In addition, a comprehensive understanding of these processes at molecular level and importance of biological adaptation for improved N and P use efficiency is discussed. PMID:26322069

  2. Altered CSMD1 Expression Alters Cocaine-Conditioned Place Preference: Mutual Support for a Complex Locus from Human and Mouse Models.

    PubMed

    Drgonova, Jana; Walther, Donna; Singhal, Sulabh; Johnson, Kennedy; Kessler, Brice; Troncoso, Juan; Uhl, George R

    2015-01-01

    The CUB and sushi multiple domains 1 (CSMD1) gene harbors signals provided by clusters of nearby SNPs with 10-2 > p > 10-8 associations in genome wide association (GWAS) studies of addiction-related phenotypes. A CSMD1 intron 3 SNP displays p < 10-8 association with schizophrenia and more modest associations with individual differences in performance on tests of cognitive abilities. CSDM1 encodes a cell adhesion molecule likely to influence development, connections and plasticity of brain circuits in which it is expressed. We tested association between CSMD1 genotypes and expression of its mRNA in postmortem human brains (n = 181). Expression of CSMD1 mRNA in human postmortem cerebral cortical samples differs 15-25%, in individuals with different alleles of simple sequence length and SNP polymorphisms located in the gene's third/fifth introns, providing nominal though not Bonferroni-corrected significance. These data support mice with altered CSMD1 expression as models for common human CSMD1 allelic variation. We tested baseline and/or cocaine-evoked addiction, emotion, motor and memory-related behaviors in +/- and -/- csmd1 knockout mice on mixed and on C57-backcrossed genetic backgrounds. Initial csmd1 knockout mice on mixed genetic backgrounds displayed a variety of coat colors and sizable individual differences in responses during behavioral testing. Backcrossed mice displayed uniform black coat colors. Cocaine conditioned place preference testing revealed significant influences of genotype (p = 0.02). Homozygote knockouts displayed poorer performance on aspects of the Morris water maze task. They displayed increased locomotion in some, though not all, environments. The combined data thus support roles for common level-of-expression CSMD1 variation in a drug reward phenotype relevant to addiction and in cognitive differences that might be relevant to schizophrenia. Mouse model results can complement data from human association findings of modest magnitude that

  3. Resonant condition for storage ring short wavelength FEL with power exceeding Renieri limit

    SciTech Connect

    Litvinenko, V.N.; Burnham, B.; Wu, Y.

    1995-12-31

    In this paper we discuss the possibility of operating a storage ring FEL with resonant conditions providing for preservation of electron beam structure on an optical wave scale. We suggest tuning the storage ring betatron and synchrotron tunes on one of the high (N-th) order resonances to compensate dynamic diffusion of optical phase. This mode of operation does not require isochronicity of the ring lattice. In these conditions optical phase will be restored after N turns around the ring and stochastic conditions used in the derivation of Renieri limit are no longer applicable. We discuss the influence of high order terms in electron motion, RF frequency stability, and synchrotron radiation effects on preservation of optical phase.

  4. Limiting conditions of the horizontal transmission of the Drosophila C virus in its host ( D. melanogaster)

    NASA Astrophysics Data System (ADS)

    Gomariz-Zilber, Eliane; Jeune, Bernard; Thomas-Orillard, Michèle

    1998-04-01

    We carried out experiments with virus infected females on the horizontal transmission of Drosophila C virus on artificial culture medium and under controlled conditions. The numerical results made it possible to build up an empirical model. We tested the values of the rearing parameters under nearly natural conditions in boxes containing pieces of rotting apple. A good agreement between observed and estimated values led to the following conclusions: (i) The horizontal transmission of the Drosophila C virus is facilitated via the contamination of the nutritive medium by the cadavers or the feces of virus-infected females (ii) The contamination depends on the richness of viral particles of the contaminating flies. We also confirmed under 'natural' conditions the insufficient contamination of the male flies which justifies the use of females as 'reservoirs' of the virus. The estimation of the biological limiting conditions for horizontal transfer of the virus is the following: a minimum of two contaminating females have to stay for at least two days on an initially uninfected milieu so that a durable contamination of at least some females results. Under these conditions, the richness in viral particles in the contaminated flies is lower than that in the contaminating females and therefore the long term virus infection remains problematical.

  5. Universal limiting shape of worn profile under multiple-mode fretting conditions: theory and experimental evidence

    NASA Astrophysics Data System (ADS)

    Dmitriev, Andrey I.; Voll, Lars B.; Psakhie, Sergey G.; Popov, Valentin L.

    2016-03-01

    We consider multiple-mode fretting wear in a frictional contact of elastic bodies subjected to a small-amplitude oscillation, which may include in-plane and out-of-plane translation, torsion and tilting (“periodic rolling”). While the detailed kinetics of wear depends on the particular loading history and wear mechanism, the final worn shape, under some additional conditions, occurs to be universal for all types and loading and wear mechanisms. This universal form is determined solely by the radius of the permanent stick region and the maximum indentation depth during the loading cycle. We provide experimental evidence for the correctness of the theoretically predicted limiting shape. The existence of the universal limiting shape can be used for designing joints which are resistant to fretting wear.

  6. Universal limiting shape of worn profile under multiple-mode fretting conditions: theory and experimental evidence

    PubMed Central

    Dmitriev, Andrey I.; Voll, Lars B.; Psakhie, Sergey G.; Popov, Valentin L.

    2016-01-01

    We consider multiple-mode fretting wear in a frictional contact of elastic bodies subjected to a small-amplitude oscillation, which may include in-plane and out-of-plane translation, torsion and tilting (“periodic rolling”). While the detailed kinetics of wear depends on the particular loading history and wear mechanism, the final worn shape, under some additional conditions, occurs to be universal for all types and loading and wear mechanisms. This universal form is determined solely by the radius of the permanent stick region and the maximum indentation depth during the loading cycle. We provide experimental evidence for the correctness of the theoretically predicted limiting shape. The existence of the universal limiting shape can be used for designing joints which are resistant to fretting wear. PMID:26979092

  7. Calcification and photosynthesis of the coral acropora cervicornis under calcium limited conditions

    NASA Technical Reports Server (NTRS)

    Rathfon, Megan; Brewer, Debbie

    1997-01-01

    Differing hypothesis about the function of calcification are based on an interesting dilemma. Is the purpose of calcification mainly a structural and protective one or does calcification serve other functions? Does photosynthesis increase carbonate ion activity and cause calcification or does calcification increase CO2 levels and stimulate photsynthesis? It is proposed that calcification in corals is not dependent upon photosynthesis but upon calcium levels in the water. Under normal ocean conditions, corals convert a certain percentage of energy to photosynthesis and respiration and another percentage to calcification. As corals become nutrient stressed, particularly calcium limited, the ratio of photosynthesis to calcification shifts towards calcification in order to generate protons. The protons generated during calcification may stimulate photosynthesis and aid in the uptake of nutrients and biocarbonates. The results of the calcification experiment show a trend towards increased calcification and decreased photosynthesis when the coral Acropora cervicornis is calcium limited, but the data are inconclusive and further research is needed.

  8. 26 CFR 1.831-1 - Tax on insurance companies (other than life or mutual), mutual marine insurance companies, and...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... mutual), mutual marine insurance companies, and mutual fire insurance companies issuing perpetual... insurance companies (other than life or mutual), mutual marine insurance companies, and mutual fire... marine insurance companies and mutual fire insurance companies exclusively issuing either...

  9. A necessary condition for applying MUSIC algorithm in limited-view inverse scattering problem

    NASA Astrophysics Data System (ADS)

    Park, Taehoon; Park, Won-Kwang

    2015-09-01

    Throughout various results of numerical simulations, it is well-known that MUltiple SIgnal Classification (MUSIC) algorithm can be applied in the limited-view inverse scattering problems. However, the application is somehow heuristic. In this contribution, we identify a necessary condition of MUSIC for imaging of collection of small, perfectly conducting cracks. This is based on the fact that MUSIC imaging functional can be represented as an infinite series of Bessel function of integer order of the first kind. Numerical experiments from noisy synthetic data supports our investigation.

  10. Pedestrian evacuation in view and hearing limited condition: The impact of communication and memory

    NASA Astrophysics Data System (ADS)

    Xue, Shuqi; Jia, Bin; Jiang, Rui; Shan, Jingjing

    2016-09-01

    This paper studies pedestrian evacuation in view and hearing limited condition based on the social force approach. It is assumed that there are two types of pedestrians: Informed individuals know the exit location whereas uninformed individuals do not. The uninformed individuals can communicate with the informed ones within their perceptual fields, thus learning to know and memorize the exit location. We consider cases with and without communication/memory. The simulations show communication and memory are able to enhance the evacuation efficiency. We also investigate the impact of communication on the efficiency of an emergency exit.

  11. Assessment of bacterial community structure in nitrifying biofilm under inorganic carbon-sufficient and -limited conditions.

    PubMed

    Bae, Hyokwan; Chung, Yun-Chul; Yang, Heejeong; Lee, Changsoo; Aryapratama, Rio; Yoo, Young J; Lee, Seockheon

    2015-01-01

    In this work, nitrification and changes in the composition of the total bacterial community under inorganic carbon (IC)-limited conditions, in a nitrifying moving bed biofilm reactor, was investigated. A culture-independent analysis of cloning and sequencing based on the 16S rRNA gene was applied to quantify the bacterial diversity and to determine bacterial taxonomic assignment. IC concentrations had significant effects on the stability of ammonia-oxidation as indicated by the reduction of the nitrogen conversion rate with high NH4(+)-N loadings. The predominance of Nitrosomonas europaea was maintained in spite of changes in the IC concentration. In contrast, heterotrophic bacterial species contributed to a high bacterial diversity, and to a dynamic shift in the bacterial community structure, under IC-limited conditions. In this study, individual functions of heterotrophic bacteria were estimated based on taxonomic information. Possible key roles of coexisting heterotrophic bacteria are the assimilation of organic compounds of extracellular polymeric substances produced by nitrifiers, and biofilm formation by providing a filamentous structure and aggregation properties.

  12. Growth and physiology of Thiobacillus novellus under nutrient-limited mixotrophic conditions.

    PubMed Central

    Leefeldt, R H; Matin, A

    1980-01-01

    Thiobacillus novellus was cultivated in a chemostate under the individual limitations of thiosulfate, glucose, and thiosulfate plus glucose. At dilution rate (D) of 0.05 h-1 or lower, the steady-state biomass concentration in mixotrophic medium was additive of the heterotrophic and autotrophic biomass at corresponding D values. The ambient concentrations of thiosulfate, glucose, or both in the various cultures were low and were very similar in mixotrophic, heterotrophic, and autotrophic environments at a given D value. At D = 0.05 h-1, mixotrophic cells possessed higher activities of sulfite oxidase and thiosulfate oxidation compared to autotrophic cells, as well as higher activities of glucose enzymes and glucose oxidation than heterotrophic cells. Thus, in contrast to nutrient-excess conditions, in nutrient-limited mixotrophic environments at these D values, T. novellus did not exhibit characteristics of uncoupled substrate oxidation, inhibition of substrate utilization, and repression of enzymes of energy metabolism. It is concluded that T. novellus responds to mixotrophic growth conditions differently in environments of different nutritional status, and the ecological and physiological significance of this finding is discussed. PMID:7380804

  13. Microbial lipid production by Rhodosporidium toruloides under sulfate-limited conditions.

    PubMed

    Wu, Siguo; Zhao, Xin; Shen, Hongwei; Wang, Qian; Zhao, Zongbao K

    2011-01-01

    Novel biochemical approaches remain to be developed to improve microbial lipid technology. This study demonstrated that sulfate limitation was effective to promote accumulating substantial amounts of intracellular lipid by the oleaginous yeast Rhodosporidium toruloides Y4. When it was cultivated using a medium with an initial carbon-to-sulfur (C/S) molar ratio of 46,750, cellular lipid content reached up to 58.3%. The time courses of cell growth, lipid accumulation and nutrient depletion were analyzed and discussed in terms of lipid biosynthesis. Moreover, lipid accumulation under sulfate-limited conditions was effective regardless of the presence of a high concentration of nitrogen sources. Thus, lipid contents almost held constant at near 57% in the media with an initial C/S molar ratio of 11,380 although the carbon-to-nitrogen molar ratio ranged from 28.3 to 5.7. Taken together, our results established the sulfate-limitation approach to control lipid biosynthesis, which should be valuable to explore nitrogen-rich raw materials as the feedstock for lipid production.

  14. Oceanographic Conditions Limit the Spread of a Marine Invader along Southern African Shores

    PubMed Central

    Nicastro, Katy R.; Zardi, Gerardo I.; McQuaid, Christopher D.; Serrão, Ester A.

    2015-01-01

    Invasive species can affect the function and structure of natural ecological communities, hence understanding and predicting their potential for spreading is a major ecological challenge. Once established in a new region, the spread of invasive species is largely controlled by their dispersal capacity, local environmental conditions and species interactions. The mussel Mytilus galloprovincialis is native to the Mediterranean and is the most successful marine invader in southern Africa. Its distribution there has expanded rapidly and extensively since the 1970s, however, over the last decade its spread has ceased. In this study, we coupled broad scale field surveys, Ecological Niche Modelling (ENM) and Lagrangian Particle Simulations (LPS) to assess the current invaded distribution of M. galloprovincialis in southern Africa and to evaluate what prevents further spread of this species. Results showed that all environmentally suitable habitats in southern Africa have been occupied by the species. This includes rocky shores between Rocky Point in Namibia and East London in South Africa (approx. 2800 km) and these limits coincide with the steep transitions between cool-temperate and subtropical-warmer climates, on both west and southeast African coasts. On the west coast, simulations of drifting larvae almost entirely followed the northward and offshore direction of the Benguela current, creating a clear dispersal barrier by advecting larvae away from the coast. On the southeast coast, nearshore currents give larvae the potential to move eastwards, against the prevalent Agulhas current and beyond the present distributional limit, however environmental conditions prevent the establishment of the species. The transition between the cooler and warmer water regimes is therefore the main factor limiting the northern spread on the southeast coast; however, biotic interactions with native fauna may also play an important role. PMID:26114766

  15. Estimating mutual information

    NASA Astrophysics Data System (ADS)

    Kraskov, Alexander; Stögbauer, Harald; Grassberger, Peter

    2004-06-01

    We present two classes of improved estimators for mutual information M(X,Y) , from samples of random points distributed according to some joint probability density μ(x,y) . In contrast to conventional estimators based on binnings, they are based on entropy estimates from k -nearest neighbor distances. This means that they are data efficient (with k=1 we resolve structures down to the smallest possible scales), adaptive (the resolution is higher where data are more numerous), and have minimal bias. Indeed, the bias of the underlying entropy estimates is mainly due to nonuniformity of the density at the smallest resolved scale, giving typically systematic errors which scale as functions of k/N for N points. Numerically, we find that both families become exact for independent distributions, i.e. the estimator M̂ (X,Y) vanishes (up to statistical fluctuations) if μ(x,y)=μ(x)μ(y) . This holds for all tested marginal distributions and for all dimensions of x and y . In addition, we give estimators for redundancies between more than two random variables. We compare our algorithms in detail with existing algorithms. Finally, we demonstrate the usefulness of our estimators for assessing the actual independence of components obtained from independent component analysis (ICA), for improving ICA, and for estimating the reliability of blind source separation.

  16. MYB10 and MYB72 Are Required for Growth under Iron-Limiting Conditions

    PubMed Central

    Palmer, Christine M.; Hindt, Maria N.; Schmidt, Holger; Clemens, Stephan; Guerinot, Mary Lou

    2013-01-01

    Iron is essential for photosynthesis and is often a limiting nutrient for plant productivity. Plants respond to conditions of iron deficiency by increasing transcript abundance of key genes involved in iron homeostasis, but only a few regulators of these genes have been identified. Using genome-wide expression analysis, we searched for transcription factors that are induced within 24 hours after transferring plants to iron-deficient growth conditions. Out of nearly 100 transcription factors shown to be up-regulated, we identified MYB10 and MYB72 as the most highly induced transcription factors. Here, we show that MYB10 and MYB72 are functionally redundant and are required for plant survival in alkaline soil where iron availability is greatly restricted. myb10myb72 double mutants fail to induce transcript accumulation of the nicotianamine synthase gene NAS4. Both myb10myb72 mutants and nas4-1 mutants have reduced iron concentrations, chlorophyll levels, and shoot mass under iron-limiting conditions, indicating that these genes are essential for proper plant growth. The double myb10myb72 mutant also showed nickel and zinc sensitivity, similar to the nas4 mutant. Ectopic expression of NAS4 rescues myb10myb72 plants, suggesting that loss of NAS4 is the primary defect in these plants and emphasizes the importance of nicotianamine, an iron chelator, in iron homeostasis. Overall, our results provide evidence that MYB10 and MYB72 act early in the iron-deficiency regulatory cascade to drive gene expression of NAS4 and are essential for plant survival under iron deficiency. PMID:24278034

  17. The terrestrial green macroalga Prasiola calophylla (Trebouxiophyceae, Chlorophyta): ecophysiological performance under water-limiting conditions.

    PubMed

    Holzinger, Andreas; Herburger, Klaus; Blaas, Kathrin; Lewis, Louise A; Karsten, Ulf

    2017-01-09

    The phylogenetic placement of Prasiola calophylla, from an anthropogenic habitat previously shown to contain a novel UV sunscreen compound, was confirmed by analysis of its rbcL gene. This alga has the capacity to tolerate strong water-limiting conditions. The photosynthetic performance and ultrastructural changes under desiccation and osmotic stress were investigated. Freshly harvested thalli showed an effective quantum yield of PSII [Y(II)] of 0.52 ± 0.06 that decreased to ∼60% of the initial value at 3000 mM sorbitol, and 4000 mM sorbitol led to a complete loss of Y(II). The Y(II) of thalli exposed to controlled desiccating conditions at 60% relative humidity (RH) ceased within 240 min, whereas zero values were reached after 120 min at 20% RH. All investigated samples completely recovered Y(II) within ∼100 min after rehydration. Relative electron transport rates (rETR) were temperature dependent, increasing from 5, 10, to 25 °C but strongly declining at 45 °C. Transmission electron microscopy of samples desiccated for 2.5 h showed an electron dense appearance of the entire cytoplasm when compared to control samples. Thylakoid membranes were still visible in desiccated cells, corroborating the ability to recover. Control and desiccated cells contained numerous storage lipids and starch grains, providing reserves. Overall, P. calophylla showed a high capacity to cope with water-limiting conditions on a physiological and structural basis. A lipophilic outer layer of the cell walls might contribute to reduce water evaporation in this poikilohydric organism.

  18. Optimization of plant mineral nutrition under growth-limiting conditions in a lunar greenhouse

    NASA Astrophysics Data System (ADS)

    Zaets, I.; Voznyuk, T.; Kovalchuk, M.; Rogutskyy, I.; Lukashov, D.; Mytrokhyn, O.; Mashkovska, S.; Foing, B.; Kozyrovska, N.

    It may be assumed that the first plants in a lunar base will play a main role in forming a protosoil of acceptable fertility needed for purposively growing second generation plants like wheat, rice, tulips, etc. The residues of the first-generation plants could be composted and transformed by microorganisms into a soil-like substrate within a loop of regenerative life support system. The lunar regolith may be used as a substrate for plant growth at the very beginning of a mission to reduce its cost. The use of microbial communities for priming plants will allow one to facilitate adaption to stressful conditions and to support the plant development under growth limiting conditions. Well-defined plant-associated bacteria were used for growing three cultivars to colonize French marigold (Tagetes patula L.) in anorthosite, a substrate of low bioavailability, analogous to a lunar rock. The consortium was composed of plant growth promoting rhizobacteria and the bacterium Paenibacillus sp. IMBG156 which stimulated seed germination, better plant development, and finally, the flowering of inoculated tagetes. In contrast, control plants grew poorly in the anorthosite and practically did not survive until flowering. Analysis of bacterial community composition showed that all species colonized plant roots, however, the rate of colonization depended on the allelopatic characteristics of marigold varieties. Bacteria of consortium were able to liberate some elements (Ca, Fe, Mn, Si, Ni, Cu, Zn) from substrate anorthosite. Plant colonization by mixed culture of bacterial strains resulted in the increase of accumulation of K, Mg, Mn by the plant and in the lowering of the level of toxic metal accumulation. It was assumed that a rationally assembled consortium of bacterial strains promoted germination of marygold seeds and supported the plant development under growth limiting conditions by means of bioleaching plant essential nutritional elements and by protecting the plant against

  19. Genomic sweep and potential genetic rescue during limiting environmental conditions in an isolated wolf population.

    PubMed

    Adams, Jennifer R; Vucetich, Leah M; Hedrick, Philip W; Peterson, Rolf O; Vucetich, John A

    2011-11-22

    Genetic rescue, in which the introduction of one or more unrelated individuals into an inbred population results in the reduction of detrimental genetic effects and an increase in one or more vital rates, is a potentially important management tool for mitigating adverse effects of inbreeding. We used molecular techniques to document the consequences of a male wolf (Canis lupus) that immigrated, on its own, across Lake Superior ice to the small, inbred wolf population in Isle Royale National Park. The immigrant's fitness so exceeded that of native wolves that within 2.5 generations, he was related to every individual in the population and his ancestry constituted 56 per cent of the population, resulting in a selective sweep of the total genome. In other words, all the male ancestry (50% of the total ancestry) descended from this immigrant, plus 6 per cent owing to the success of some of his inbred offspring. The immigration event occurred in an environment where space was limiting (i.e. packs occupied all available territories) and during a time when environmental conditions had deteriorated (i.e. wolves' prey declined). These conditions probably explain why the immigration event did not obviously improve the population's demography (e.g. increased population numbers or growth rate). Our results show that the beneficial effects of gene flow may be substantial and quickly manifest, short-lived under some circumstances, and how the demographic benefits of genetic rescue might be masked by environmental conditions.

  20. Soil texture and climatc conditions for biocrust growth limitation: a meta analysis

    NASA Astrophysics Data System (ADS)

    Fischer, Thomas; Subbotina, Mariia

    2015-04-01

    clay content and with study site as a random effect. (III) Threshold values of texture and climatc effects were identified using a regression tree. Three mean annual temperature classes for texture dependent BSC growth limitation were identified: (1) <9 °C with a threshold value of 25% silt and clay (limited growth on coarser soils), (2) 9-19 °C, where texture did have no influence on relative crust biomass, and (3) >19 °C at soils with <4 or >17% silt and clay. Because biocrust development is limited under certain climatic and soil texture conditions, it is suggested to consider soil texture for biocrust rehabilitation purposes and in biogeochemical modeling of cryptogamic ground covers. References Belnap, J. & Eldridge, D. 2001. Disturbance and Recovery of Biological Soil Crusts. In: Belnap, J. & Lange, O. (eds.) Biological Soil Crusts: Structure, Function, and Management, Springer, Berlin. Belnap, J. 2001. Biological Soil Crusts and Wind Erosion. In: Belnap, J. & Lange, O. (eds.) Fischer, T., Subbotina, M. 2014. Climatic and soil texture threshold values for cryptogamic cover development: a meta analysis. Biologia 69/11:1520-1530,

  1. Structure of curved crystals in the thermodynamic limit and the perfect screening condition

    NASA Astrophysics Data System (ADS)

    Travesset, Alex

    2016-12-01

    The dislocation and disclination density defining the structure of a crystal constrained on a general curved background is computed analytically in the thermodynamic limit, when the number of particles is arbitrarily large. It is shown that the minimum of the elastic energy, where strains are optimally close to zero, can be formulated in terms of a connection (a rule on how to parallel transport vectors), which allows to provide an explicit solution in the thermodynamic limit that consists of disclinations surrounded by scars (grain boundaries with variable spacing). The approach allows to compute the interaction potential. For a sphere, a full characterization of the scars is provided, and it is shown that the potential of interaction among disclinations "dressed" by scars is inversely proportional to the sinus of the geodesic distance and that the ground state consists of 12 dressed disclinations that display icosahedral symmetry. The case of a torus is also considered. More generally, the thermodynamic solution implements a "perfect screening" condition, where defects completely screen the Gaussian curvature. Implications for the problem of melting are discussed.

  2. Limitations of ichnofossil approach for evaluating paleo-bottom-water redox conditions

    SciTech Connect

    Savrda, C.E.; Bottjer, D.

    1987-05-01

    Information on trace fossil diversity, burrow size, and depth of burrow penetration has been incorporated into an ichnofossil tiering model designed for the evaluation of paleo-bottom-water redox conditions. Previous applications to a variety of Phanerozoic strata indicate that this trace fossil approach is more effective than previously emphasized criteria for reconstructing relative degree of oxygenation as well as rates and magnitudes of temporal change in oxygenation. However, the trace fossil model is not without limitations. Presently, they recognize four factors that could limit the accuracy of ichnology-based redox reconstructions: (1) information loss - increases in penetration depth (associated with reoxygenation) that occur at rates in excess of sedimentation rate will destroy a portion of the previous record of oxygenation whereas extended residence times of deep-tier organisms may mask the record through excessive overprinting; (2) inadequate structure visibility - required information on trace fossil assemblage composition and cross cutting relationships is unobtainable for strata where original or diagenetically enhanced contrast between burrows and surrounding sediments is lacking; (3) complexity introduced by rapid deposition - periodic turbidite deposition can mask the desired oxygen signal through substrate modification, temporary modification of faunal composition and behavior, and/or temporary water chemistry changes; and (4) changes in substrate consistency - temporal variation in substrate stiffness (e.g., development of firmgrounds) may result in intrastratal variation in trace fossil tiering structure. The success of future applications of the ichnologic approach depends upon thorough consideration of these factors.

  3. Cultivar Mixture Cropping Increased Water Use Efficiency in Winter Wheat under Limited Irrigation Conditions

    PubMed Central

    Wang, Yunqi; Zhang, Yinghua; Ji, Wei; Yu, Peng; Wang, Bin; Li, Jinpeng; Han, Meikun; Xu, Xuexin; Wang, Zhimin

    2016-01-01

    The effects of cultivar mixture cropping on yield, biomass, and water use efficiency (WUE) in winter wheat (Triticum aestivum L.) were investigated under non-irrigation (W0, no irrigation during growth stage), one time irrigation (W1, irrigation applied at stem elongation) and two times irrigation (W2, irrigation applied at stem elongation and anthesis) conditions. Nearly 90% of cultivar mixture cropping treatments experienced an increase in grain yield as compared with the mean of the pure stands under W0, those for W1 and W2 were 80% and 85%, respectively. Over 75% of cultivar mixture cropping treatments got greater biomass than the mean of the pure stands under the three irrigation conditions. Cultivar mixture cropping cost more water than pure stands under W0 and W1, whereas the water consumption under W2 decreased by 5.9%–6.8% as compared with pure stands. Approximately 90% of cultivar mixtures showed an increase of 5.4%–34.5% in WUE as compared with the mean of the pure stands, and about 75% of cultivar mixtures had 0.8%–28.5% higher WUE than the better pure stands under W0. Similarly, there were a majority of mixture cropping treatments with higher WUE than the mean and the better one of the pure stands under W1 and W2. On the whole, proper cultivar mixture cropping could increase yield and WUE, and a higher increase in WUE occurred under limited irrigation condition. PMID:27362563

  4. Uncertainty relation for mutual information

    NASA Astrophysics Data System (ADS)

    Schneeloch, James; Broadbent, Curtis J.; Howell, John C.

    2014-12-01

    We postulate the existence of a universal uncertainty relation between the quantum and classical mutual informations between pairs of quantum systems. Specifically, we propose that the sum of the classical mutual information, determined by two mutually unbiased pairs of observables, never exceeds the quantum mutual information. We call this the complementary-quantum correlation (CQC) relation and prove its validity for pure states, for states with one maximally mixed subsystem, and for all states when one measurement is minimally disturbing. We provide results of a Monte Carlo simulation suggesting that the CQC relation is generally valid. Importantly, we also show that the CQC relation represents an improvement to an entropic uncertainty principle in the presence of a quantum memory, and that it can be used to verify an achievable secret key rate in the quantum one-time pad cryptographic protocol.

  5. 29 CFR Appendix A to Subpart T to... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., presence of residual effects, response to therapy, number of occurrences, diving mode, or degree and... or drug use. Conditions requiring continuous medication for control (e.g., antihistamines, steroids, barbiturates, moodaltering drugs, or insulin). Meniere's disease. Hemoglobinopathies. Obstructive...

  6. Transcriptional Characterization of a Widely-Used Grapevine Rootstock Genotype under Different Iron-Limited Conditions.

    PubMed

    Vannozzi, Alessandro; Donnini, Silvia; Vigani, Gianpiero; Corso, Massimiliano; Valle, Giorgio; Vitulo, Nicola; Bonghi, Claudio; Zocchi, Graziano; Lucchin, Margherita

    2016-01-01

    Iron chlorosis is a serious deficiency that affects orchards and vineyards reducing quality and yield production. Chlorotic plants show abnormal photosynthesis and yellowing shoots. In grapevine iron uptake and homeostasis are most likely controlled by a mechanism known as "Strategy I," characteristic of non-graminaceous plants and based on a system of soil acidification, iron reduction and transporter-mediated uptake. Nowadays, grafting of varieties of economic interest on tolerant rootstocks is widely used practice against many biotic and abiotic stresses. Nevertheless, many interspecific rootstocks, and in particular those obtained by crossing exclusively non-vinifera genotypes, can show limited nutrient uptake and transport, in particular for what concerns iron. In the present study, 101.14, a commonly used rootstock characterized by susceptibility to iron chlorosis was subjected to both Fe-absence and Fe-limiting conditions. Grapevine plantlets were grown in control, Fe-deprived, and bicarbonate-supplemented hydroponic solutions. Whole transcriptome analyses, via mRNA-Seq, were performed on root apices of stressed and unstressed plants. Analysis of differentially expressed genes (DEGs) confirmed that Strategy I is the mechanism responsible for iron uptake in grapevine, since many orthologs genes to the Arabidopsis "ferrome" were differentially regulated in stressed plant. Molecular differences in the plant responses to Fe absence and presence of bicarbonate were also identified indicating the two treatments are able to induce response-mechanisms only partially overlapping. Finally, we measured the expression of a subset of genes differentially expressed in 101.14 (such as IRT1, FERRITIN1, bHLH38/39) or known to be fundamental in the "strategy I" mechanism (AHA2 and FRO2) also in a tolerant rootstock (M1) finding important differences which could be responsible for the different degrees of tolerance observed.

  7. Transcriptional Characterization of a Widely-Used Grapevine Rootstock Genotype under Different Iron-Limited Conditions

    PubMed Central

    Vannozzi, Alessandro; Donnini, Silvia; Vigani, Gianpiero; Corso, Massimiliano; Valle, Giorgio; Vitulo, Nicola; Bonghi, Claudio; Zocchi, Graziano; Lucchin, Margherita

    2017-01-01

    Iron chlorosis is a serious deficiency that affects orchards and vineyards reducing quality and yield production. Chlorotic plants show abnormal photosynthesis and yellowing shoots. In grapevine iron uptake and homeostasis are most likely controlled by a mechanism known as “Strategy I,” characteristic of non-graminaceous plants and based on a system of soil acidification, iron reduction and transporter-mediated uptake. Nowadays, grafting of varieties of economic interest on tolerant rootstocks is widely used practice against many biotic and abiotic stresses. Nevertheless, many interspecific rootstocks, and in particular those obtained by crossing exclusively non-vinifera genotypes, can show limited nutrient uptake and transport, in particular for what concerns iron. In the present study, 101.14, a commonly used rootstock characterized by susceptibility to iron chlorosis was subjected to both Fe-absence and Fe-limiting conditions. Grapevine plantlets were grown in control, Fe-deprived, and bicarbonate-supplemented hydroponic solutions. Whole transcriptome analyses, via mRNA-Seq, were performed on root apices of stressed and unstressed plants. Analysis of differentially expressed genes (DEGs) confirmed that Strategy I is the mechanism responsible for iron uptake in grapevine, since many orthologs genes to the Arabidopsis “ferrome” were differentially regulated in stressed plant. Molecular differences in the plant responses to Fe absence and presence of bicarbonate were also identified indicating the two treatments are able to induce response-mechanisms only partially overlapping. Finally, we measured the expression of a subset of genes differentially expressed in 101.14 (such as IRT1, FERRITIN1, bHLH38/39) or known to be fundamental in the “strategy I” mechanism (AHA2 and FRO2) also in a tolerant rootstock (M1) finding important differences which could be responsible for the different degrees of tolerance observed. PMID:28105035

  8. Performance of Airborne Precision Spacing Under Realistic Wind Conditions and Limited Surveillance Range

    NASA Technical Reports Server (NTRS)

    Wieland, Frederick; Santos, Michel; Krueger, William; Houston, Vincent E.

    2011-01-01

    With the expected worldwide increase of air traffic during the coming decade, both the Federal Aviation Administration's (FAA's) Next Generation Air Transportation System (NextGen), as well as Eurocontrol's Single European Sky ATM Research (SESAR) program have, as part of their plans, air traffic management (ATM) solutions that can increase performance without requiring time-consuming and expensive infrastructure changes. One such solution involves the ability of both controllers and flight crews to deliver aircraft to the runway with greater accuracy than they can today. Previous research has shown that time-based spacing techniques, wherein the controller assigns a time spacing to each pair of arriving aircraft, can achieve this goal by providing greater runway delivery accuracy and producing a concomitant increase in system-wide performance. The research described herein focuses on one specific application of time-based spacing, called Airborne Precision Spacing (APS), which has evolved over the past ten years. This research furthers APS understanding by studying its performance with realistic wind conditions obtained from atmospheric sounding data and with realistic wind forecasts obtained from the Rapid Update Cycle (RUC) short-range weather forecast. In addition, this study investigates APS performance with limited surveillance range, as provided by the Automatic Dependent Surveillance-Broadcast (ADS-B) system, and with an algorithm designed to improve APS performance when ADS-B surveillance data is unavailable. The results presented herein quantify the runway threshold delivery accuracy of APS under these conditions, and also quantify resulting workload metrics such as the number of speed changes required to maintain spacing.

  9. Do water-limiting conditions predispose Norway spruce to bark beetle attack?

    PubMed Central

    Netherer, Sigrid; Matthews, Bradley; Katzensteiner, Klaus; Blackwell, Emma; Henschke, Patrick; Hietz, Peter; Pennerstorfer, Josef; Rosner, Sabine; Kikuta, Silvia; Schume, Helmut; Schopf, Axel

    2015-01-01

    Drought is considered to enhance susceptibility of Norway spruce (Picea abies) to infestations by the Eurasian spruce bark beetle (Ips typographus, Coleoptera: Curculionidae), although empirical evidence is scarce. We studied the impact of experimentally induced drought on tree water status and constitutive resin flow, and how physiological stress affects host acceptance and resistance. We established rain-out shelters to induce both severe (two full-cover plots) and moderate (two semi-cover plots) drought stress. In total, 18 sample trees, which were divided equally between the above treatment plots and two control plots, were investigated. Infestation was controlled experimentally using a novel ‘attack box’ method. Treatments influenced the ratios of successful and defended attacks, but predisposition of trees to infestation appeared to be mainly driven by variations in stress status of the individual trees over time. With increasingly negative twig water potentials and decreasing resin exudation, the defence capability of the spruce trees decreased. We provide empirical evidence that water-limiting conditions impair Norway spruce resistance to bark beetle attack. Yet, at the same time our data point to reduced host acceptance byI. typographus with more extreme drought stress, indicated by strongly negative pre-dawn twig water potentials. PMID:25417785

  10. Do water-limiting conditions predispose Norway spruce to bark beetle attack?

    PubMed

    Netherer, Sigrid; Matthews, Bradley; Katzensteiner, Klaus; Blackwell, Emma; Henschke, Patrick; Hietz, Peter; Pennerstorfer, Josef; Rosner, Sabine; Kikuta, Silvia; Schume, Helmut; Schopf, Axel

    2015-02-01

    Drought is considered to enhance susceptibility of Norway spruce (Picea abies) to infestations by the Eurasian spruce bark beetle (Ips typographus, Coleoptera: Curculionidae), although empirical evidence is scarce. We studied the impact of experimentally induced drought on tree water status and constitutive resin flow, and how physiological stress affects host acceptance and resistance. We established rain-out shelters to induce both severe (two full-cover plots) and moderate (two semi-cover plots) drought stress. In total, 18 sample trees, which were divided equally between the above treatment plots and two control plots, were investigated. Infestation was controlled experimentally using a novel 'attack box' method. Treatments influenced the ratios of successful and defended attacks, but predisposition of trees to infestation appeared to be mainly driven by variations in stress status of the individual trees over time. With increasingly negative twig water potentials and decreasing resin exudation, the defence capability of the spruce trees decreased. We provide empirical evidence that water-limiting conditions impair Norway spruce resistance to bark beetle attack. Yet, at the same time our data point to reduced host acceptance by I. typographus with more extreme drought stress, indicated by strongly negative pre-dawn twig water potentials.

  11. Kinetically limited weathering at low denudation rates in semiarid climatic conditions

    NASA Astrophysics Data System (ADS)

    Schoonejans, Jérôme; Vanacker, Veerle; Opfergelt, Sophie; Ameijeiras-Mariño, Yolanda; Christl, Marcus

    2016-02-01

    Biogeochemical cycling within the Critical Zone depends on the interactions between minerals and fluids controlling chemical weathering and physical erosion rates. In this study, we explore the role of water availability in controlling soil chemical weathering in semiarid climatic conditions. Weathering rates and intensities were evaluated for nine soil profiles located on convex ridge crests of three mountain ranges in the Spanish Betic Cordillera. We combine a geochemical mass balance with 10Be cosmogenic nuclides to constrain chemical weathering intensities and long-term denudation rates. As such, this study presents new data on chemical weathering and 10Be-derived denudation for understudied semiarid climate systems. In the Betic Cordillera, chemical weathering intensities are relatively low (~5 to 30% of the total denudation of the soil) and negatively correlated with the magnitude of the water deficit in soils. Chemical mass losses are inversely related to denudation rates (14-109 mm/kyr) and positively to soil thickness (14-58 cm); these results are consistent with kinetic limitation of chemical weathering rates. A worldwide compilation of chemical weathering data suggests that soil water balance may regulate the coupling between chemical weathering and physical erosion by modulating soil solute fluxes. Therefore, future landscape evolution models that seek to link chemical weathering and physical erosion should include soil water flux as an essential driver of weathering.

  12. 26 CFR 54.9801-3 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... Example 4. (i) Facts. A group health plan provides coverage for the treatment of acne, subject to a lifetime limit of $2,000. The plan counts against this $2,000 lifetime limit on acne treatment...

  13. 45 CFR 146.111 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... this section. Example 4. (i) Facts. A group health plan provides coverage for the treatment of acne, subject to a lifetime limit of $2,000. The plan counts against this $2,000 lifetime limit acne...

  14. Predicted limits for evaporative cooling in heat stress relief of cattle in warm conditions.

    PubMed

    Berman, A

    2009-10-01

    Evaporative cooling of ambient air (EC) is a main path for heat stress relief in cattle kept in the shade of semi-confining structures. Evaporative cooling is particularly efficient in hot dry climates. We examined the potential of EC for heat stress relief in cattle in moderately warm and humid climates. The feasibility was examined by the reduction in ambient temperature (T(ac)) produced by EC as a function of ambient temperature (T(a)) and humidity (RH(a)). A data set (n = 139) of temperature and relative humidity (RH) produced by EC over a range of air temperature (25 to 50 degrees C) and humidity (10 to 70% RH) was analyzed by polynomial second order regressions. The analyses produced equations for the relations between ambient air temperature and ambient humidity and between respective conditions in air cooled by EC (T(c), RH(c)). Linear regressions were computed for a narrower temperature range (30 to 40 degrees C). In all equations, R(2) were >0.94 and regression terms were statistically significant. The T(ac) obtained by EC diminished by 0.3 degrees C per degrees C rise in T(a), indicating a reduced efficiency of EC with rising T(a). The T(ac) obtained by EC also was markedly reduced by rising ambient humidity and increased by RH(c). An attempt to sustain T(ac) at greater RH(a) by allowing a rise in RH(c) would only restore 2/3 of the reduction in T(ac) because the coefficient for the RH(a) effect on T(ac) is 1.5 larger than that of RH(c). The T(ac) attained by EC partially depends on the humidity in the cooled environment. Elevated RH(c) may impede animal skin and respiratory evaporative heat loss and lead to moisture accumulation in bedding. If the upper desired limit for RH(c) is 70%, at RH(a) smaller than 45% (typical for hot-dry environments) the T(ac) is larger than 7.5 degrees C, at RH(a) greater than 55% T(ac) is reduced to less than 5 degrees C, and at RH(a) of 57.5 to 60% T(ac) is about 2.5 degrees C. Coupling EC with forced air movement when T

  15. Blood culture series benefit may be limited to selected clinical conditions: time to reassess.

    PubMed

    Khatib, R; Simeunovic, G; Sharma, M; Fakih, M G; Johnson, L B; Briski, L; Lebar, W

    2015-04-01

    Blood cultures are often submitted as series (two to three sets per 24 hours) to maximize sample recovery. We assessed the actual benefit of additional sets. Blood cultures submitted from adults (≥ 18 years old) over 1 year (1 February 2012 to 31 January 2013) were examined. The medical records of patients with positive cultures were reviewed. Cultures with commensal organisms were considered contamination in the absence of a source and clinical findings. The impact of additional sets on antibiotic therapy was estimated. We evaluated 15,394 blood cultures. They were submitted as two to five sets per 24 hours in 12,236 (79.5%) instances. Pathogens were detected in 1227 sets, representing 741 bacteremias, of which 618 (83.4%) were detected in the first set and 123 (16.6%) in the additional sets. Pathogens missed in the first set were recovered from patients receiving antibiotics (n = 72; 58.5%) and after undergoing a procedure (n = 54; 43.9%). The additional sets' results could have influenced antibiotic therapy in 76/6235 (1.2%) instances, including 40 (0.6%) antibiotic switches and 36 (0.6%) possible extensions of therapy. The potential impact of the detection of missed pathogens on antibiotic therapy was not apparent in patients who had an endovascular infection (26/27, 96.3%) and those who lacked an obvious source of pathogens (10/10, 100%). These findings suggest that one blood culture is probably adequate in patients with an obvious source of pathogens. Blood culture series are beneficial in patients without an obvious source of pathogens and in those with endovascular infections. It is time to reassess the benefit of blood culture series, perhaps limiting them to selected conditions.

  16. Metabolomic Profiling of 13 Diatom Cultures and Their Adaptation to Nitrate-Limited Growth Conditions.

    PubMed

    Bromke, Mariusz A; Sabir, Jamal S; Alfassi, Fahad A; Hajarah, Nahid H; Kabli, Saleh A; Al-Malki, Abdulrahman L; Ashworth, Matt P; Méret, Michaël; Jansen, Robert K; Willmitzer, Lothar

    2015-01-01

    Diatoms are very efficient in their use of available nutrients. Changes in nutrient availability influence the metabolism and the composition of the cell constituents. Since diatoms are valuable candidates to search for oil producing algae, measurements of diatom-produced compounds can be very useful for biotechnology. In order to explore the diversity of lipophilic compounds produced by diatoms, we describe the results from an analysis of 13 diatom strains. With the help of a lipidomics platform, which combines an UPLC separation with a high resolution/high mass accuracy mass spectrometer, we were able to measure and annotate 142 lipid species. Out of these, 32 were present in all 13 cultures. The annotated lipid features belong to six classes of glycerolipids. The data obtained from the measurements were used to create lipidomic profiles. The metabolomic overview of analysed cultures is amended by the measurement of 96 polar compounds. To further increase the lipid diversity and gain insight into metabolomic adaptation to nitrogen limitation, diatoms were cultured in media with high and low concentrations of nitrate. The growth in nitrogen-deplete or nitrogen-replete conditions affects metabolite accumulation but has no major influence on the species-specific metabolomic profile. Thus, the genetic component is stronger in determining metabolic patterns than nitrogen levels. Therefore, lipid profiling is powerful enough to be used as a molecular fingerprint for diatom cultures. Furthermore, an increase of triacylglycerol (TAG) accumulation was observed in low nitrogen samples, although this trend was not consistent across all 13 diatom strains. Overall, our results expand the current understanding of metabolomics diversity in diatoms and confirm their potential value for producing lipids for either bioenergy or as feed stock.

  17. 26 CFR 54.9801-3 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... provides coverage for the treatment of diabetes, generally not subject to any lifetime dollar limit. However, if an individual was diagnosed with diabetes before the effective date of coverage under the plan, diabetes coverage is subject to a lifetime limit of $10,000. (ii) Conclusion. In this Example 3, the...

  18. 45 CFR 146.111 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... health plan provides coverage for the treatment of diabetes, generally not subject to any lifetime dollar limit. However, if an individual was diagnosed with diabetes before the effective date of coverage under the plan, diabetes coverage is subject to a lifetime limit of $10,000. (ii) Conclusion. In...

  19. 29 CFR 2590.701-3 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... provides coverage for the treatment of diabetes, generally not subject to any lifetime dollar limit. However, if an individual was diagnosed with diabetes before the effective date of coverage under the plan, diabetes coverage is subject to a lifetime limit of $10,000. (ii) Conclusion. In this Example 3, the...

  20. 26 CFR 54.9801-3 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... provides coverage for the treatment of diabetes, generally not subject to any lifetime dollar limit. However, if an individual was diagnosed with diabetes before the effective date of coverage under the plan, diabetes coverage is subject to a lifetime limit of $10,000. (ii) Conclusion. In this Example 3, the...

  1. 29 CFR 2590.701-3 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... provides coverage for the treatment of diabetes, generally not subject to any lifetime dollar limit. However, if an individual was diagnosed with diabetes before the effective date of coverage under the plan, diabetes coverage is subject to a lifetime limit of $10,000. (ii) Conclusion. In this Example 3, the...

  2. 45 CFR 146.111 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... health plan provides coverage for the treatment of diabetes, generally not subject to any lifetime dollar limit. However, if an individual was diagnosed with diabetes before the effective date of coverage under the plan, diabetes coverage is subject to a lifetime limit of $10,000. (ii) Conclusion. In...

  3. 26 CFR 54.9801-3 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... provides coverage for the treatment of diabetes, generally not subject to any lifetime dollar limit. However, if an individual was diagnosed with diabetes before the effective date of coverage under the plan, diabetes coverage is subject to a lifetime limit of $10,000. (ii) Conclusion. In this Example 3, the...

  4. 40 CFR 122.44 - Establishing limitations, standards, and other permit conditions (applicable to State NPDES...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., or controls a pollutant or practice not limited in the permit. (d) Water quality standards and State... quality. (i) Limitations must control all pollutants or pollutant parameters (either conventional...; (ii) Requirements for construction site operators to control waste such as discarded...

  5. 76 FR 25648 - Special Conditions: Gulfstream Model GVI Airplane; Limit Engine Torque Loads for Sudden Engine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-05

    ..., the engine mounts and the supporting structures must be designed to withstand a ``limit engine torque... structures be able to support limit loads without detrimental permanent deformation, meaning that supporting... of producing much higher transient loads on the engine mounts and supporting structures. As a...

  6. On the nonradiative and quasistatic conditions and the limitations of circuit theory

    NASA Astrophysics Data System (ADS)

    Zozaya, Alfonso

    2007-06-01

    Field theory is used to analyze a simple circuit and to deduce the conditions for nonradiative and quasistatic fields. From the condition for quasistatic fields, which is the more stringent of the two, Kirchhoff's voltage equation and its range of validity are deduced. These conditions for the validity of circuit theory are not treated appropriately in the undergraduate curricula. A simple numerical problem is given to illustrate these ideas.

  7. Mutual Respect and Civic Education

    ERIC Educational Resources Information Center

    Bird, Colin

    2010-01-01

    Contemporary theories of civic education frequently appeal to an ideal of mutual respect in the context of ethical, ethical and religious disagreement. This paper critically examines two recently popular criticisms of this ideal. The first, coming from a postmodern direction, charges that the ideal is hypocritical in its effort to be maximally…

  8. Hospital mutual aid evacuation plan.

    PubMed

    Phillips, R

    1997-02-01

    Health care facilities need to be prepared for disasters such as floods, tornadoes and earthquakes. Rochester, NY, and its surrounding communities devised a hospital mutual aid evacuation plan in the event a disaster occurs and also to comply with the Joint Commission. This document discusses the plan's development process and also provides the end result.

  9. 42 CFR 410.37 - Colorectal cancer screening tests: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Colorectal cancer screening tests: Conditions for...) BENEFITS Medical and Other Health Services § 410.37 Colorectal cancer screening tests: Conditions for and...) Colorectal cancer screening tests means any of the following procedures furnished to an individual for...

  10. 42 CFR 410.37 - Colorectal cancer screening tests: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Colorectal cancer screening tests: Conditions for...) BENEFITS Medical and Other Health Services § 410.37 Colorectal cancer screening tests: Conditions for and...) Colorectal cancer screening tests means any of the following procedures furnished to an individual for...

  11. 42 CFR 410.37 - Colorectal cancer screening tests: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false Colorectal cancer screening tests: Conditions for...) BENEFITS Medical and Other Health Services § 410.37 Colorectal cancer screening tests: Conditions for and...) Colorectal cancer screening tests means any of the following procedures furnished to an individual for...

  12. 42 CFR 410.37 - Colorectal cancer screening tests: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Colorectal cancer screening tests: Conditions for...) BENEFITS Medical and Other Health Services § 410.37 Colorectal cancer screening tests: Conditions for and...) Colorectal cancer screening tests means any of the following procedures furnished to an individual for...

  13. 42 CFR 410.37 - Colorectal cancer screening tests: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 2 2012-10-01 2012-10-01 false Colorectal cancer screening tests: Conditions for...) BENEFITS Medical and Other Health Services § 410.37 Colorectal cancer screening tests: Conditions for and...) Colorectal cancer screening tests means any of the following procedures furnished to an individual for...

  14. Prediction of sand transport over immobile gravel from supply limited to capacity conditions.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prediction of the transport of sand in armored gravel reaches downstream of dams is complicated by variable bed conditions ranging from sand transported through gravel to sand in transport over buried gravel. Knowledge of the rate of sand transport in these conditions, however, is necessary for...

  15. Limited condition dependence of male acoustic signals in the grasshopper Chorthippus biguttulus

    PubMed Central

    Franzke, Alexandra; Reinhold, Klaus

    2012-01-01

    In many animal species, male acoustic signals serve to attract a mate and therefore often play a major role for male mating success. Male body condition is likely to be correlated with male acoustic signal traits, which signal male quality and provide choosy females indirect benefits. Environmental factors such as food quantity or quality can influence male body condition and therefore possibly lead to condition-dependent changes in the attractiveness of acoustic signals. Here, we test whether stressing food plants influences acoustic signal traits of males via condition-dependent expression of these traits. We examined four male song characteristics, which are vital for mate choice in females of the grasshopper Chorthippus biguttulus. Only one of the examined acoustic traits, loudness, was significantly altered by changing body condition because of drought- and moisture-related stress of food plants. No condition dependence could be observed for syllable to pause ratio, gap duration within syllables, and onset accentuation. We suggest that food plant stress and therefore food plant quality led to shifts in loudness of male grasshopper songs via body condition changes. The other three examined acoustic traits of males do not reflect male body condition induced by food plant quality. PMID:22957192

  16. An Analysis of Sequential Variables in Pavlovian Conditioning Employing Extended and Limited Acquisition Training

    ERIC Educational Resources Information Center

    Miller, Ronald Mellado; Capaldi, E. John

    2006-01-01

    Sequential theory's memory model of learning has been successfully applied in response contingent instrumental conditioning experiments (Capaldi, 1966, 1967, 1994; Capaldi & Miller, 2003). However, it has not been systematically tested in nonresponse contingent Pavlovian conditioning experiments. The present experiments attempted to determine if…

  17. Employment status, employment conditions, and limiting illness: prospective evidence from the British household panel survey 1991–2001

    PubMed Central

    Bartley, M; Sacker, A; Clarke, P

    2004-01-01

    Objectives: To assess the relation of the incidence of, and recovery from, limiting illness to employment status, occupational social class, and income over time in an initially healthy sample of working age men and women. Methods: Cox proportional hazards models. Results: There were large differences in the risk of limiting illness according to occupational social class, with men and women in the least favourable employment conditions nearly four times more likely to become ill than those in the most favourable. Unemployment and economic inactivity also had a powerful effect on illness incidence. Limiting illness was not a permanent state for most participants in the study. Employment status was also related to recovery. Conclusions: Having secure employment in favourable working conditions greatly reduces the risk of healthy people developing limiting illness. Secure employment increases the likelihood of recovery. These findings have considerable implications for both health inequality and economic policies. PMID:15143119

  18. Condition and size of damselflies: a field study of food limitation.

    PubMed

    Baker, Robert L

    1989-10-01

    Based on evidence from field manipulations, several authors have recently suggested that interference competition among larval odonates reduces individual growth rates and biomass by reducing foraging rates. This study was designed to test the effects of food shortage on "condition" (relative mass per unit head width) of larval Ischnura verticalis (Odonata: Coenagrionidae) under laboratory conditions and to use these results to estimate the degree of food shortage of larvae under naturally occurring field conditions. In the laboratory, there were marked differences in condition of larvae fed diets ranging from ad libitum feeding with worms to ad libitum feeding with Daphnia 1 day out of every 8. Condition of larvae collected from May through October from 17 different sites in southern Ontario indicated that, for most of the year, larvae had conditions similar to those fed ad libitum with Daphnia in the laboratory. There was no evidence that larval condition was related to population density. Condition of larvae in most sites during July was similar to that of larvae fed poor diets in the laboratory. It is unlikely that the low conditions were due to competition as there were no correlations with density across sites and population densities during July were at their lowest. Adult head widths showed a seasonal decline from mid June to the end of the flight season. There was no evidence that head widths were related to population density although there was some evidence that head widths of males were positively related to larval condition. My results do not support the hypothesis that competition is important in affecting foraging rates and subsequent development of larvae. Contrasts between my results and other studies may stem from difficulties with the interpretation of field experiments, that densities in my study may have been low due to fish predation, and/or that I. verticalis larvae are slow moving relative to other larvae and thus less likely to interact.

  19. System-Wide Adaptations of Desulfovibrio alaskensis G20 to Phosphate-Limited Conditions

    PubMed Central

    Schubotz, Florence; de Santiago-Torio, Ana; Kuehl, Jennifer V.; Carlson, Hans K.; Watson, Nicki; Daye, Mirna; Summons, Roger E.; Arkin, Adam P.; Deutschbauer, Adam M.

    2016-01-01

    The prevalence of lipids devoid of phosphorus suggests that the availability of phosphorus limits microbial growth and activity in many anoxic, stratified environments. To better understand the response of anaerobic bacteria to phosphate limitation and starvation, this study combines microscopic and lipid analyses with the measurements of fitness of pooled barcoded transposon mutants of the model sulfate reducing bacterium Desulfovibrio alaskensis G20. Phosphate-limited G20 has lower growth rates and replaces more than 90% of its membrane phospholipids by a mixture of monoglycosyl diacylglycerol (MGDG), glycuronic acid diacylglycerol (GADG) and ornithine lipids, lacks polyphosphate granules, and synthesizes other cellular inclusions. Analyses of pooled and individual mutants reveal the importance of the high-affinity phosphate transport system (the Pst system), PhoR, and glycolipid and ornithine lipid synthases during phosphate limitation. The phosphate-dependent synthesis of MGDG in G20 and the widespread occurrence of the MGDG/GADG synthase among sulfate reducing ∂-Proteobacteria implicate these microbes in the production of abundant MGDG in anaerobic environments where the concentrations of phosphate are lower than 10 μM. Numerous predicted changes in the composition of the cell envelope and systems involved in transport, maintenance of cytoplasmic redox potential, central metabolism and regulatory pathways also suggest an impact of phosphate limitation on the susceptibility of sulfate reducing bacteria to other anthropogenic or environmental stresses. PMID:28030630

  20. Assessment and treatment of nonpain conditions in life-limiting disease.

    PubMed

    Villalobos, Alice E

    2011-05-01

    The "Pawspice" philosophy, which the author introduced at the 2000 American Veterinary Medical Association meeting, focuses on symptom management along with a kinder, gentler, or modified approach to standard therapy. Many veterinarians have preconceived bias or ingrained beliefs about aging, serious illness, multiple comorbidities, and cancer, which may cause a negative or dismissive approach toward palliative treatment, especially in geriatric pets. Veterinarians and their v-teams must overcome this insensitive attitude about life-limiting disease. This article describes assessment, treatment, and home management of some nonpainful life-limiting diseases, including cancer and age-related decline of vital functions in the Pawspice setting.

  1. Nematode-Bacteria Mutualism: Selection Within the Mutualism Supersedes Selection Outside of the Mutualism

    PubMed Central

    Morran, Levi T.; Penley, McKenna J.; Byrd, Victoria S.; Meyer, Andrew J.; O’Sullivan, Timothy S.; Bashey, Farrah; Goodrich-Blair, Heidi; Lively, Curtis M.

    2016-01-01

    The coevolution of interacting species can lead to co-dependent mutualists. Little is known about the effect of selection on partners within verses apart from the association. Here, we determined the effect of selection on bacteria (Xenorhabdus nematophila) both within and apart from its mutualistic partner (a nematode, Steinernema carpocapsae). In nature, the two species cooperatively infect and kill arthropods. We passaged the bacteria either together with (M+), or isolated from (M−), nematodes under two different selection regimes: random selection (S−) and selection for increased virulence against arthropod hosts (S+). We found that the isolated bacteria evolved greater virulence under selection for greater virulence (M−S+) than under random selection (M−S−). In addition, the response to selection in the isolated bacteria (M−S+) caused a breakdown of the mutualism following reintroduction to the nematode. Finally, selection for greater virulence did not alter the evolutionary trajectories of bacteria passaged within the mutualism (M+S+ = M+S−), indicating that selection for the maintenance of the mutualism was stronger than selection for increased virulence. The results show that selection on isolated mutualists can rapidly breakdown beneficial interactions between species, but that selection within a mutualism can supersede external selection, potentially generating co-dependence over time. PMID:26867502

  2. 40 CFR 122.44 - Establishing limitations, standards, and other permit conditions (applicable to State NPDES...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... procedures which account for existing controls on point and nonpoint sources of pollution, the variability of... ocean discharges; (8) Incorporate alternative effluent limitations or standards where warranted by... identified in a storm water pollution prevention plan are adequate and properly implemented in...

  3. Inclusive and Integrated Schooling for Children with Limited Abilities: Problems and Conditions Necessary for Effectiveness

    ERIC Educational Resources Information Center

    Liubavina, N. V.

    2014-01-01

    For more than twenty years now the system of education in Russia has been adopting the ideas of integrated schooling for children with limited abilities. The absence of positive outcomes has been confirmed by the results of numerous surveys (Malofeev 2007, 2011; Nazarova 1996, 2009). In this article, N. V. Liubavina writes that the time has now…

  4. 76 FR 44245 - Special Conditions: Gulfstream Model GVI Airplane; Limit Engine Torque Loads for Sudden Engine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-25

    ... engine mounts and the supporting structures must be designed to withstand a ``limit engine torque load... occur about once in the lifetime of any airplane. Section 25.305 requires that supporting structures be... of producing much higher transient loads on the engine mounts and supporting structures. As a...

  5. Limiting conditions for applying the spherical section assumption in contact angle estimation.

    PubMed

    Chatterjee, Jaideep

    2003-03-01

    The shape of liquid drops on solid surfaces deviates from the spherical as tension decreases and gravity effects start affecting the drop shape. This paper attempts to define this deviation and estimates the dimensionless Eotvos number limits above which the deviation becomes "significant." The use of these limiting values can facilitate estimation of contact angle in the following manner. It is well known that the equilibrium contact angle made by a liquid drop on a solid surface can be estimated from measurements of two drop parameters. These parameters can be any two chosen from the drop volume, height, and wetted radius. In case the effect of gravity on the drop shape is negligible, simple algebraic relations derived from the spherical section assumption exist, from which the contact angle can be estimated. In systems where the "spherical section" assumption is invalid, the Laplace equation for the drop shape has been solved numerically with any two of the above parameters as the constraints, to obtain the contact angle. In this paper, Eotvos numbers at which the deviation of the drop profile from the spherical is significant enough to result in contact angle deviation of 1 degrees are estimated. The limiting values of Eotvos number, expressed as a function of the original contact angle made by the spherical profile, are obtained by solving the Laplace equation for the drop shape with the drop volume and wetted radius constraints for decreasing values of Interfacial tension. These limiting values are also estimated for different drop sizes and for cases where the drop phase is heavier (sessile) and lighter (buoyant) than the surrounding fluid. The independence of the Eotvos number estimates from the sign of the density difference as well as the drop size is shown. These Eotvos number limits can be used to check if the spherical section assumption, with the resulting simple algebraic relations, can be used for contact angle estimation and other shape

  6. Monitoring strategies for re-establishment of ecological reference conditions: possibilities and limitations.

    PubMed

    Alve, Elisabeth; Lepland, Aivo; Magnusson, Jan; Backer-Owe, Kristian

    2009-01-01

    The ecological status of an environment should be evaluated by comparison with local "reference conditions", here defined as the pre-industrial ecological status of the 19th century. This pilot study illustrates how micropalaeontological monitoring, using benthic foraminifera (protists) and associated geochemical parameters preserved in inner Oslofjord (Norway) sediments, characterise local reference conditions. In order to optimise the usefulness of the ecological information held by foraminifera and enable characterisation of temporal changes in environmental quality beyond time intervals covered by biological time-series, the Norwegian governmental macrofauna-based classification system is applied on fossil benthic foraminiferal assemblages. Quantitative comparisons demonstrate deteriorating ecological status in response to increased anthropogenic forcing (eutrophication, micropollutants), including a 73% loss in number of foraminiferal species. Despite reduced pollution during the past decades and, at one site, capping of polluted sediments with clean clay, the reference conditions are far from re-established. Micropalaeontological monitoring requires net sediment accumulation basins and careful considerations of taphonomic processes.

  7. 76 FR 63822 - Special Conditions: Gulfstream Aerospace LP (GALP) Model G280 Airplane, Limit Engine Torque Loads...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-14

    ...) Model G280 Airplane, Limit Engine Torque Loads for Sudden Engine Stoppage AGENCY: Federal Aviation... conditions are issued for the Gulfstream Aerospace LP (GALP) model G280 airplane. This airplane will have a...: Federal Aviation Administration, Transport Airplane Directorate, Attn: Rules Docket (ANM-113), Docket...

  8. 7 CFR 301.76-5 - General conditions governing the issuance of any certificate or limited permit; provisions for...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Citrus Greening and Asian Citrus Psyllid § 301.76-5 General conditions governing the issuance of any certificate or limited... Act (7 U.S.C. 7714) 2 /> to prevent the spread of Asian citrus psyllid; and 2 An inspector may...

  9. 7 CFR 301.76-5 - General conditions governing the issuance of any certificate or limited permit; provisions for...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Citrus Greening and Asian Citrus Psyllid § 301.76-5 General conditions governing the issuance of any certificate or limited... Act (7 U.S.C. 7714) 2 /> to prevent the spread of Asian citrus psyllid; and 2 An inspector may...

  10. 7 CFR 301.76-5 - General conditions governing the issuance of any certificate or limited permit; provisions for...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Citrus Greening and Asian Citrus Psyllid § 301.76-5 General conditions governing the issuance of any certificate or limited... Act (7 U.S.C. 7714) 2 to prevent the spread of Asian citrus psyllid; and 2 An inspector may hold...

  11. 7 CFR 301.76-5 - General conditions governing the issuance of any certificate or limited permit; provisions for...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Citrus Greening and Asian Citrus Psyllid § 301.76-5 General conditions governing the issuance of any certificate or limited... Act (7 U.S.C. 7714) 2 /> to prevent the spread of Asian citrus psyllid; and 2 An inspector may...

  12. 20 CFR 661.310 - Under what limited conditions may a Local Board directly be a provider of core services...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Under what limited conditions may a Local Board directly be a provider of core services, intensive services, or training services, or act as a One-Stop Operator? 661.310 Section 661.310 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR STATEWIDE AND...

  13. 20 CFR 661.310 - Under what limited conditions may a Local Board directly be a provider of core services...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Under what limited conditions may a Local...-Stop Operator? 661.310 Section 661.310 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR STATEWIDE AND LOCAL GOVERNANCE OF THE WORKFORCE INVESTMENT SYSTEM UNDER TITLE I OF...

  14. 20 CFR 661.310 - Under what limited conditions may a Local Board directly be a provider of core services...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 4 2012-04-01 2012-04-01 false Under what limited conditions may a Local...-Stop Operator? 661.310 Section 661.310 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) STATEWIDE AND LOCAL GOVERNANCE OF THE WORKFORCE INVESTMENT SYSTEM UNDER...

  15. GCM Simulations of Neoproterozoic "Snowball Earth" Conditions: Implications for the Environmental Limits on Terrestrial Metazoans and Their Extraterrestrial Analogues

    NASA Technical Reports Server (NTRS)

    Sohl, L. E.; Chandler, M. A.

    2001-01-01

    The Neoproterozoic Snowball Earth intervals provide excellent opportunities to examine the environmental limits on terrestrial metazoans. A series of GCM simulations was run in order to quantify climatic conditions during these intervals. Additional information is contained in the original extended abstract.

  16. High-frequency limit of the transport cross section in scattering by an obstacle with impedance boundary conditions

    NASA Astrophysics Data System (ADS)

    Aleksenko, A. I.; Cruz, J. P.; Lakshtanov, E. L.

    2008-06-01

    The scalar scattering of a plane wave by a strictly convex obstacle with impedance boundary conditions is considered. A uniform bound of the total cross section for all values of the frequency is presented. The high-frequency limit of the transport cross section is calculated and presented as a classical functional of the variational calculus.

  17. 42 CFR 410.19 - Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage. 410.19 Section 410.19 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL...

  18. 42 CFR 410.19 - Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage. 410.19 Section 410.19 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL...

  19. 42 CFR 410.19 - Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 2 2012-10-01 2012-10-01 false Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage. 410.19 Section 410.19 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL...

  20. 42 CFR 410.19 - Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage. 410.19 Section 410.19 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL...

  1. Photosystem II cycle activity and alternative electron transport in the diatom Phaeodactylum tricornutum under dynamic light conditions and nitrogen limitation.

    PubMed

    Wagner, Heiko; Jakob, Torsten; Lavaud, Johann; Wilhelm, Christian

    2016-05-01

    Alternative electron sinks are an important regulatory mechanism to dissipate excessively absorbed light energy particularly under fast changing dynamic light conditions. In diatoms, the cyclic electron transport (CET) around Photosystem II (PS II) is an alternative electron transport pathway (AET) that contributes to avoidance of overexcitation under high light illumination. The combination of nitrogen limitation and high-intensity irradiance regularly occurs under natural conditions and is expected to force the imbalance between light absorption and the metabolic use of light energy. The present study demonstrates that under N limitation, the amount of AET and the activity of CETPSII in the diatom Phaeodactylum tricornutum were increased. Thereby, the activity of CETPSII was linearly correlated with the amount of AET rates. It is concluded that CETPSII significantly contributes to AET in P. tricornutum. Surprisingly, CETPSII was found to be activated already at the end of the dark period under N-limited conditions. This coincided with a significantly increased degree of reduction of the plastoquinone (PQ) pool. The analysis of the macromolecular composition of cells of P. tricornutum under N-limited conditions revealed a carbon allocation in favor of carbohydrates during the light period and their degradation during the dark phase. A possible linkage between the activity of CETPSII and degree of reduction of the PQ pool on the one side and the macromolecular changes on the other is discussed.

  2. Performance of transient limiters under laboratory, simulated, and rocket-triggered lightning conditions

    SciTech Connect

    Hasbrouck, R.T.; Johnson, J.P.; Breitmeier, J.

    1989-07-02

    We have designed and tested a prototype system that implements a lightning-protection method referred to as the ''fortress concept.'' The fortress, a structure similar to a Faraday cage, protects the critical system by surrounding it with a continuous metallic skin. Each electrical conductor that must enter the fortress is enclosed within a cable, which is, in turn, enclosed in a metallic shield that terminates at the entry point and is electrically bonded to the fortress' outer metallic surface. Within the fortress, each penetrating conductor is protected by a transient limiter. The system was tested by means of full-threat-level simulated lightning and actual lightening triggered by rockets. Several limited components were subsequently tested by using a laboratory-type surge generator to investigate certain anomalous responses. This paper reviews the fortress concept, discusses the operation of the limiters, and examines their performance. Explanations are offered for the anomalous responses, and several important design considerations and trade-offs are offered. 3 refs., 15 figs.

  3. A general framework for effectiveness concepts in mutualisms.

    PubMed

    Schupp, Eugene W; Jordano, Pedro; Gómez, José María

    2017-03-28

    A core interest in studies of mutualistic interactions is the 'effectiveness' of mutualists in providing benefits to their partners. In plant-animal mutualisms it is widely accepted that the total effect of a mutualist on its partner is estimated as (1) a 'quantity' component multiplied by (2) a 'quality' component, although the meanings of 'effectiveness,' 'quantity,' and 'quality' and which terms are applied to these metrics vary greatly across studies. In addition, a similar quantity × quality = total effect approach has not been applied to other types of mutualisms, although it could be informative. Lastly, when a total effect approach has been applied, it has invariably been from a phytocentric perspective, focussing on the effects of animal mutualists on their plant partner. This lack of a common framework of 'effectiveness' of mutualistic interactions limits generalisation and the development of a broader understanding of the ecology and evolution of mutualisms. In this paper, we propose a general framework and demonstrate its utility by applying it to both partners in five different types of mutualisms: pollination, seed dispersal, plant protection, rhizobial, and mycorrhizal mutualisms. We then briefly discuss the flexibility of the framework, potential limitations, and relationship to other approaches.

  4. Pluto-charon mutual events

    SciTech Connect

    Binzel, R.P. )

    1989-11-01

    Since 1985, planetary astronomers have been working to take advantage of a once-per-century apparent alignment between Pluto and its satellite, Charon, which has allowed mutual occultation and transit events to be observed. There events, which will cease in 1990, have permitted the first precise determinations of their individual radii, densities, and surface compositions. In addition, information on their surface albedo distributions can be obtained.

  5. The effect of limiter conditioning on the Tokamak Fusion Test Reactor edge plasma

    SciTech Connect

    Kilpatrick, S.J.; Manos, D.M.; Nyberg, I.; Ramsey, A.T.; Stratton, B.C.; Timberlake, J.; Ulrickson, M.J.; Pitcher, C.S.; Dylla, H.F.

    1991-07-01

    Measurements by moveable Langmuir probes and edge spectroscopy diagnostics have documented the conditioning effect of low density helium-initiated discharge sequences on the Tokamak Fusion Test Reactor (TFTR) edge plasma. Langmuir probe measurements show in general that the edge electron density n{sub e} decreases by less than a factor of 2 while the edge electron temperature T{sub e} doubles. Radial profiles to the plasma boundary show that the density scrape-off length increases somewhat while the temperature scrape-off length decreases substantially. The particle flux density is unaffected. The spectral emission of C 2 decreases by a factor of 2, a much smaller change than that exhibited by the D{sub {alpha}} signal. These results complement previous accounts of the conditioning technique. Comparisons of these He conditioning measurements are made to edge measurements during a deuterium density scan experiment, showing many similarities, and to an existing edge model of the conditioning process, showing qualitative agreement. 20 refs., 5 figs.

  6. The effect of limiter conditioning on the Tokamak Fusion Test Reactor edge plasma

    SciTech Connect

    Kilpatrick, S.J.; Pitcher, C.S.; Dylla, H.F.; Manos, D.M.; Nyberg, I.; Ramsey, A.T.; Stratton, B.C.; Timberlake, J.; Ulrickson, M.J. )

    1991-05-01

    Measurements by moveable Langmuir probes and edge spectroscopy diagnostics have documented the conditioning effect of low-density helium-initiated discharge sequences on the Tokamak Fusion Test Reactor edge plasma. Langmuir probe measurements shown in general that the edge electron density {ital n}{sub {ital e}} decreases by less than a factor of 2 while the edge electron temperature {ital T}{sub {ital e}} doubles. Radial profiles to the plasma boundary show that the density scrape-off length increases somewhat while the temperature scrape-off length decreases substantially. The particle flux density is unaffected. The spectral emission of C II decreases by a factor of 2, a much smaller change than that exhibited by the {ital D}{sub {alpha}} signal. These results complement previous accounts of the conditioning technique. Comparisons of these He conditioning measurements are made to edge measurements during a deuterium density scan experiment, showing many similarities, and to an existing edge model of the conditioning process, showing qualitative agreement.

  7. 26 CFR 54.9801-3 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... cancer. A was not diagnosed with breast cancer at any time prior to A's enrollment date in the plan. Nine months after A's enrollment date in the plan, A is diagnosed with breast cancer. (ii) Conclusion. In this Example, the plan may not impose a preexisting condition exclusion with respect to A's breast...

  8. 45 CFR 146.111 - Limitations on preexisting condition exclusion period.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... on genetic information, A has a predisposition towards breast cancer. A was not diagnosed with breast... plan, A is diagnosed with breast cancer. (ii) Conclusion. In this Example, the plan may not impose a preexisting condition exclusion with respect to A's breast cancer because, prior to A's enrollment date, A...

  9. 42 CFR 410.16 - Initial preventive physical examination: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) BENEFITS Medical and Other Health Services § 410.16 Initial preventive physical examination: Conditions for... Part B benefits as described in sections 1861(s)(10), (jj), (nn), (oo), (pp), (qq)(1), (rr), (uu), (vv... and vitamins. (3) Family history, including a review of medical events in the beneficiary's...

  10. 42 CFR 410.16 - Initial preventive physical examination: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) BENEFITS Medical and Other Health Services § 410.16 Initial preventive physical examination: Conditions for... Part B benefits as described in sections 1861(s)(10), (jj), (nn), (oo), (pp), (qq)(1), (rr), (uu), (vv... and vitamins. (3) Family history, including a review of medical events in the beneficiary's...

  11. 42 CFR 410.16 - Initial preventive physical examination: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) BENEFITS Medical and Other Health Services § 410.16 Initial preventive physical examination: Conditions for... Part B benefits as described in sections 1861(s)(10), (jj), (nn), (oo), (pp), (qq)(1), (rr), (uu), (vv... and vitamins. (3) Family history, including a review of medical events in the beneficiary's...

  12. 42 CFR 410.16 - Initial preventive physical examination: Conditions for and limitations on coverage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) BENEFITS Medical and Other Health Services § 410.16 Initial preventive physical examination: Conditions for... Part B benefits as described in sections 1861(s)(10), (jj), (nn), (oo), (pp), (qq)(1), (rr), (uu), (vv... and vitamins. (3) Family history, including a review of medical events in the beneficiary's...

  13. Microbial responses to disturbance following the conversion of CRP land to cropland under water limiting conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The conversion of Conservation Reserve Program (CRP) lands to croplands potentially reduces ecological benefits such as high soil health condition that resist to disturbance (i.e. extreme weather). Soil CO2 flux primarily comes from root and microbes’ respirations and is sensitive to changes in soil...

  14. Mutuality in the provision of Scottish healthcare.

    PubMed

    Howieson, Brian

    2015-11-01

    The backdrop to this article is provided by the Better Health, Better Care Action Plan (Scottish Government, 2007), Section 1 of which is entitled 'Towards a Mutual NHS'. According to Better Health, Better Care (Scottish Government, 2007: 5): 'Mutual organisations are designed to serve their members. They are designed to gather people around a common sense of purpose. They are designed to bring the organisation together in what people often call "co-production."' The aim of this article is to précis the current knowledge of mutuality in the provision of Scottish healthcare. In detail, it will: introduce the 'mutual' organisation; offer a historical perspective of mutuality; suggest why healthcare mutuality is important; and briefly, detail the differences in mutual health-care policy in England and Scotland. It is hoped that this analysis will help researchers and practitioners alike appreciate further the philosophy of mutuality in the provision of Scottish healthcare.

  15. An Individual-Based Diploid Model Predicts Limited Conditions Under Which Stochastic Gene Expression Becomes Advantageous

    PubMed Central

    Matsumoto, Tomotaka; Mineta, Katsuhiko; Osada, Naoki; Araki, Hitoshi

    2015-01-01

    Recent studies suggest the existence of a stochasticity in gene expression (SGE) in many organisms, and its non-negligible effect on their phenotype and fitness. To date, however, how SGE affects the key parameters of population genetics are not well understood. SGE can increase the phenotypic variation and act as a load for individuals, if they are at the adaptive optimum in a stable environment. On the other hand, part of the phenotypic variation caused by SGE might become advantageous if individuals at the adaptive optimum become genetically less-adaptive, for example due to an environmental change. Furthermore, SGE of unimportant genes might have little or no fitness consequences. Thus, SGE can be advantageous, disadvantageous, or selectively neutral depending on its context. In addition, there might be a genetic basis that regulates magnitude of SGE, which is often referred to as “modifier genes,” but little is known about the conditions under which such an SGE-modifier gene evolves. In the present study, we conducted individual-based computer simulations to examine these conditions in a diploid model. In the simulations, we considered a single locus that determines organismal fitness for simplicity, and that SGE on the locus creates fitness variation in a stochastic manner. We also considered another locus that modifies the magnitude of SGE. Our results suggested that SGE was always deleterious in stable environments and increased the fixation probability of deleterious mutations in this model. Even under frequently changing environmental conditions, only very strong natural selection made SGE adaptive. These results suggest that the evolution of SGE-modifier genes requires strict balance among the strength of natural selection, magnitude of SGE, and frequency of environmental changes. However, the degree of dominance affected the condition under which SGE becomes advantageous, indicating a better opportunity for the evolution of SGE in different genetic

  16. Factors limiting endurance of armor, artillery, and infantry units under simulated NBC conditions

    SciTech Connect

    Rauch, T.M.; Tharion, W.J.; Banderet, L.E.; Lussier, A.R.

    1986-03-13

    The war of the future will require 72-hour operations in environments contaminated with nuclear/biological/chemical (NBC) agents. The 1985 P2NBC2 (Physiological and Psychological Effects of NBC and Extended Operations on Combined Arms Crews) Program assessed soldier endurance and performance under simulated NBC conditions. A total of 175 soldiers were observed during four tests differing in design, site, climatic conditions, and performance demands. In all but one of the iterations where the full chemical-protective ensemble (MOPP 4) was used without cooling, soldier endurance fell far short of the projected requirement. Psychological data were analyzed to determine which factors were associated with the incidence of casualties. The findings showed that perceived intensity of symptoms resembling the hyperventilation syndrome was significantly greater in soldiers classified as Casualties. Five of these symptoms (painful breathing, difficulty breathing, shortness of breath, headache, and nausea) showed Casualty-Survivor differences in all tests. Symptom intensity was attributed to two factors. (1) External conditions. Thermal stress exacerbated the five basic symptoms, induced others (tetany and paresthesia), and decreased endurance. Periodic relief from respirator use attenuated these symptoms and enhanced endurance. (2) Individual differences. Significant Casualty-Survivor differences in anxiety, depression, and cognitive strategy scores indicated that perception of hyperventilation symptoms and endurance were related to personality variables. Hyperventilation symptoms could incapacitate the soldier or induce removal of the protective mask under actual chemical attack.

  17. 76 FR 36625 - Mutual Holding Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-22

    ... Office of Thrift Supervision Mutual Holding Company AGENCY: Office of Thrift Supervision (OTS), Treasury... collection. Title of Proposal: Mutual Holding Company. OMB Number: 1550-0072. Form Numbers: MHC-1 (OTS Form... whether the applicant meets the statutory and regulatory criteria to form a mutual holding company...

  18. 76 FR 20458 - Mutual Holding Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-12

    ... Office of Thrift Supervision Mutual Holding Company AGENCY: Office of Thrift Supervision (OTS), Treasury... collection. Title of Proposal: Mutual Holding Company. OMB Number: 1550-0072. Form Numbers: MHC-1 (OTS Form... whether the applicant meets the statutory and regulatory criteria to form a mutual holding company...

  19. Teleportation of qubit states through dissipative channels: Conditions for surpassing the no-cloning limit

    SciTech Connect

    Oezdemir, Sahin Kaya; Bartkiewicz, Karol; Liu, Yu-xi; Miranowicz, Adam

    2007-10-15

    We investigate quantum teleportation through dissipative channels and calculate teleportation fidelity as a function of damping rates. It is found that the average fidelity of teleportation and the range of states to be teleported depend on the type and rate of the damping in the channel. Using the fully entangled fraction, we derive two bounds on the damping rates of the channels: one is to beat the classical limit and the second is to guarantee the nonexistence of any other copy with better fidelity. The effect of the initially distributed maximally entangled state on the process is presented; the concurrence and the fully entangled fraction of the shared states are discussed. We intend to show that prior information on the dissipative channel and the range of qubit states to be teleported is helpful for the evaluation of the success of teleportation, where success is defined as surpassing the fidelity limit imposed by the fidelity of the 1-to-2 optimal cloning machine for the specific range of qubits.

  20. The solubility limited source term for cement-conditioned wastes: A status report

    SciTech Connect

    Glasser, F.P.

    1999-07-01

    An important function of the cement backfill in a nuclear waste repository is to react with aqueous waste species and reduce their solubility. However, to quantify backfill performance it is first necessary to prove the existence and establish the nature of the chemical solubility controls. This can be done by characterizing the solubility-limiting phases, determining their solubility and thermodynamic functions, and assessing their stability and persistence and solubility during backfill degradation. Much of the necessary data must be acquired experimentally. The title paper describes briefly the progress of experimental work on selected species including nickel, chromium(III,VI), tin(IV), molybdenum(VI), uranium(VI), Ce(III,IV), thorium, actinide simulants (III,IV) and chloride. Data needs are assessed and although much experimental work remains to be done, methodologies have been developed which will expedite progress. The expectation of a more quantitative performance assessment of cement barriers is, therefore, attainable.

  1. Decoupling criterion based on limited energy loss condition for groove measurement using optical scanning microscopes

    NASA Astrophysics Data System (ADS)

    Liu, Jian; Li, Mengzhou; Li, Qiang; Tan, Jiubin

    2016-12-01

    In confocal metrology, the lateral and axial responses are coupled in narrow regions near groove edges. This coupling results in an area with an uncertain profile, particularly for measurements of tight structures or deep grooves. In this paper, to delineate the area with measurement accuracy loss, an analytical model depicting the coupling relationships between the groove depth, the coupled portions and the NA of the objective used is introduced. Based on this model, the limited energy lost (LEL) decoupling criterion is presented that can enable users to choose suitable numerical apertures before performing measurements, predict the extents of the areas with measurement accuracy loss, and identify readout areas that yield accurate height measurements. The theory was verified by using confocal microscopes and is also applicable to far-field optical scanning metrology.

  2. Anhydrobiosis in yeast: FT-IR spectroscopic studies of yeast grown under conditions of severe oxygen limitation.

    PubMed

    Grube, Mara; Gavare, Marita; Rozenfelde, Linda; Rapoport, Alexander

    2014-01-01

    Anhydrobiosis is a unique state of living organisms when metabolism is temporarily and reversibly delayed in response to the extreme desiccation of cells. The production of dry active preparations of yeast grown under anaerobic conditions is not currently possible because preparations are extremely sensitive to the dehydration procedure, though they could be very helpful in different biotechnological processes, including bioethanol production. To characterize mechanisms responsible for such sensitivity to the dehydration procedure, Fourier transform infrared spectroscopy was used to study the composition of aerobically grown yeast Saccharomyces cerevisiae resistant to dehydration and grown under conditions of severe oxygen limitation and sensitive to dehydration. Results indicated that significantly lower amounts of lipids in cells, grown under conditions of severe oxygen limitation, may be related to the mechanisms of sensitivity. Dehydration of both resistant and sensitive S. cerevisiae cells was accompanied by similar changes in main cellular compounds. Amounts of nucleic acids and proteins decreased slightly, whereas that of lipids and carbohydrates increased. Artificially reduced sensitivity to dehydration in S. cerevisiae cells, grown under conditions of severe oxygen limitation, led to the increase in the lipid concentration. The chemical composition of S. cerevisiae membranes is proposed to dictate the resistance to dehydration in resistant and sensitive cells.

  3. Water-Limiting Conditions Alter the Structure and Biofilm-Forming Ability of Bacterial Multispecies Communities in the Alfalfa Rhizosphere

    PubMed Central

    Bogino, Pablo; Abod, Ayelén; Nievas, Fiorela; Giordano, Walter

    2013-01-01

    Biofilms are microbial communities that adhere to biotic or abiotic surfaces and are enclosed in a protective matrix of extracellular compounds. An important advantage of the biofilm lifestyle for soil bacteria (rhizobacteria) is protection against water deprivation (desiccation or osmotic effect). The rhizosphere is a crucial microhabitat for ecological, interactive, and agricultural production processes. The composition and functions of bacterial biofilms in soil microniches are poorly understood. We studied multibacterial communities established as biofilm-like structures in the rhizosphere of Medicago sativa (alfalfa) exposed to 3 experimental conditions of water limitation. The whole biofilm-forming ability (WBFA) for rhizospheric communities exposed to desiccation was higher than that of communities exposed to saline or nonstressful conditions. A culture-dependent ribotyping analysis indicated that communities exposed to desiccation or saline conditions were more diverse than those under the nonstressful condition. 16S rRNA gene sequencing of selected strains showed that the rhizospheric communities consisted primarily of members of the Actinobacteria and α- and γ-Proteobacteria, regardless of the water-limiting condition. Our findings contribute to improved understanding of the effects of environmental stress factors on plant-bacteria interaction processes and have potential application to agricultural management practices. PMID:24223979

  4. Ammonia-limited conditions cause of Thaumarchaeal dominance in volcanic grassland soil.

    PubMed

    Daebeler, Anne; Bodelier, Paul L E; Hefting, Mariet M; Laanbroek, Hendrikus J

    2015-03-01

    The first step of nitrification is carried out by ammonia-oxidizing bacteria (AOB) and archaea (AOA). It is largely unknown, by which mechanisms these microbes are capable of coexistence and how their respective contribution to ammonia oxidation may differ with varying soil characteristics. To determine how different levels of ammonium availability influence the extent of archaeal and bacterial contributions to ammonia oxidation, microcosm incubations with controlled ammonium levels were conducted. Net nitrification was monitored and ammonia-oxidizer communities were quantified. Additionally, the nitrification inhibitor allylthiourea (ATU) was applied to discriminate between archaeal and bacterial contributions to soil ammonia oxidation. Thaumarchaeota, which were the only ammonia oxidizers detectable at the start of the incubation, grew in all microcosms, but AOB later became detectable in ammonium amended microcosms. Low and high additions of ammonium increasingly stimulated AOB growth, while AOA were only stimulated by the low addition. Treatment with ATU had no effect on net nitrification and sizes of ammonia-oxidizing communities suggesting that the effective concentration of ATU to discriminate between archaeal and bacterial ammonia oxidation is not the same in different soils. Our results support the niche-differentiating potential of ammonium concentration for AOA and AOB, and we conclude that ammonium limitation can be a major reason for absence of detectable AOB in soil.

  5. Conditions and limitations on learning in the adaptive management of mallard harvests

    USGS Publications Warehouse

    Johnson, F.A.; Kendall, W.L.; Dubovsky, J.A.

    2002-01-01

    In 1995, the United States Fish and Wildlife Service adopted a protocol for the adaptive management of waterfowl hunting regulations (AHM) to help reduce uncertainty about the magnitude of sustainable harvests. To date, the AHM process has focused principally on the midcontinent population of mallards (Anas platyrhynchos), whose dynamics are described by 4 alternative models. Collectively, these models express uncertainty (or disagreement) about whether harvest is an additive or a compensatory form of mortality and whether the reproductive process is weakly or strongly density-dependent. Each model is associated with a probability or 'weight,' which describes its relative ability to predict changes in population size. These Bayesian probabilities are updated annually using a comparison of population size predicted under each model with that observed by a monitoring program. The current AHM process is passively adaptive, in the sense that there is no a priori consideration of how harvest decisions might affect discrimination among models. We contrast this approach with an actively adaptive approach, in which harvest decisions are used in part to produce the learning needed to increase long-term management performance. Our investigation suggests that the passive approach is expected to perform nearly as well as an optimal actively adaptive approach, particularly considering the nature of the model set, management objectives and constraints, and current regulatory alternatives. We offer some comments about the nature of the biological hypotheses being tested and describe some of the inherent limitations on learning in the AHM process.

  6. Arrays of mutually coupled receiver coils: theory and application.

    PubMed

    Wright, S M; Magin, R L; Kelton, J R

    1991-01-01

    Specialized receiver coils having a small sensitive region can provide an improvement in SNR for MR imaging and spectroscopy, at the expense of limiting the usable field of view. This work presents a technique for designing coil arrays that allows the size and location of the sensitive region to be selected remotely. Only one element of the coil array is directly connected to the receiver, allowing flexibility in system design and implementation. A method is presented for the analysis and design of mutually coupled coil arrays of any number of elements of arbitrary shape. The analysis includes mutual coupling effects between primary coils, to allow multiple primary coils to be used simultaneously. A controller system allows remote selection of the sensitive region and automatically matches the impedance of the array to the preamplifier. Results obtained using a mutually coupled coil array designed for spine imaging are shown.

  7. On the choice of limiters in a numerical approximation of a chemotaxis system with non-linear boundary conditions

    NASA Astrophysics Data System (ADS)

    Bencheva, G.

    2012-10-01

    A mathematical model for haematopoietic stem cells migration towards their niche in the bone marrow has been proposed in the literature. It consists of a chemotaxis system of partial differential equations with nonlinear boundary conditions and an additional ordinary differential equation on a part of the computational boundary. The aim in the current paper is first to answer some of the open questions of a recently introduced finite volume scheme for this chemotaxis system of differential equations and second to investigate the influence of the boundary conditions on the choice of flux limiters (the generalized minmod, Koren, van Leer limiters are investigated) used to ensure positivity and non-oscillating nature of the numerical solution.

  8. Waveguide mutually pumped phase conjugators.

    PubMed

    James, S W; Youden, K E; Jeffrey, P M; Eason, R W; Chandler, P J; Zhang, L; Townsend, P D

    1993-09-20

    The operation of the bridge mutually pumped phase conjugator is reported in a planar waveguide structure in photorefractive BaTiO(3). The waveguide was fabricated by the technique of ion implantation, using 1.5-MeVH(+) ions at a dose of 10(16) ions/cm(2). An order of magnitude decrease in response time is observed in the waveguide as compared with typical values obtained in bulk crystals, probably as a result of a combination of the optical confinement within the waveguide and possible modification of the charge-transport properties induced by the implantation process.

  9. Population dynamics and mutualism: Functional responses of benefits and costs

    USGS Publications Warehouse

    Holland, J. Nathaniel; DeAngelis, Donald L.; Bronstein, Judith L.

    2002-01-01

    We develop an approach for studying population dynamics resulting from mutualism by employing functional responses based on density‐dependent benefits and costs. These functional responses express how the population growth rate of a mutualist is modified by the density of its partner. We present several possible dependencies of gross benefits and costs, and hence net effects, to a mutualist as functions of the density of its partner. Net effects to mutualists are likely a monotonically saturating or unimodal function of the density of their partner. We show that fundamental differences in the growth, limitation, and dynamics of a population can occur when net effects to that population change linearly, unimodally, or in a saturating fashion. We use the mutualism between senita cactus and its pollinating seed‐eating moth as an example to show the influence of different benefit and cost functional responses on population dynamics and stability of mutualisms. We investigated two mechanisms that may alter this mutualism's functional responses: distribution of eggs among flowers and fruit abortion. Differences in how benefits and costs vary with density can alter the stability of this mutualism. In particular, fruit abortion may allow for a stable equilibrium where none could otherwise exist.

  10. Limited physical contact through a mesh barrier is sufficient for social reward-conditioned place preference in adolescent male rats.

    PubMed

    Peartree, Natalie A; Hood, Lauren E; Thiel, Kenneth J; Sanabria, Federico; Pentkowski, Nathan S; Chandler, Kayla N; Neisewander, Janet L

    2012-02-01

    Adolescence is a period of enhanced sensitivity to social influences and vulnerability to drug abuse. Social reward in adolescent rats has been demonstrated with the conditioned place preference (CPP) model, but it is not clear whether limited contact with another rat without play is sufficient to produce reward. We investigated this issue using an apparatus containing two main compartment, each with a wire mesh barrier that allowed rats placed on either side of the barrier to have limited physical contact. Adolescent male rats were given two conditioning sessions/day for 2 or 8 days following baseline preference tests. Rats were placed into their preferred side alone for one daily 10-min session and into their initially non-preferred side (i.e., CS) for the other session during which they either had restricted or unrestricted physical access to another rat (Rat/Mesh or Rat/Phys, respectively) or to a tennis ball (Ball/Mesh or Ball/Phys, respectively) unconditioned stimulus (US). Only the Rat/Phys group exhibited CPP after 2 CS-US pairings; however, after 8 CS-US pairings, the Rat/Mesh and Ball/Phys groups also exhibited CPP. During conditioning, the rat US elicited more robust approach and contact behavior compared to the ball, regardless of physical or restricted access. The incidence of contact and/or approach increased as the number of exposures increased. The results suggest that the rank order of US reward efficacy was physical contact with a rat>limited contact with a rat>physical contact with a ball, and that rough-and-tumble play is not necessary to establish social reward-CPP. The findings have important implications for emerging drug self-administration models in which two rats self-administering drug intravenously have limited physical contact via a mesh barrier shared between their respective operant conditioning chambers.

  11. Profiling of spatial metabolite distributions in wheat leaves under normal and nitrate limiting conditions

    PubMed Central

    Allwood, J. William; Chandra, Surya; Xu, Yun; Dunn, Warwick B.; Correa, Elon; Hopkins, Laura; Goodacre, Royston; Tobin, Alyson K.; Bowsher, Caroline G.

    2015-01-01

    The control and interaction between nitrogen and carbon assimilatory pathways is essential in both photosynthetic and non-photosynthetic tissue in order to support metabolic processes without compromising growth. Physiological differences between the basal and mature region of wheat (Triticum aestivum) primary leaves confirmed that there was a change from heterotrophic to autotrophic metabolism. Fourier Transform Infrared (FT-IR) spectroscopy confirmed the suitability and phenotypic reproducibility of the leaf growth conditions. Principal Component–Discriminant Function Analysis (PC–DFA) revealed distinct clustering between base, and tip sections of the developing wheat leaf, and from plants grown in the presence or absence of nitrate. Gas Chromatography-Time of Flight/Mass Spectrometry (GC-TOF/MS) combined with multivariate and univariate analyses, and Bayesian network (BN) analysis, distinguished different tissues and confirmed the physiological switch from high rates of respiration to photosynthesis along the leaf. The operation of nitrogen metabolism impacted on the levels and distribution of amino acids, organic acids and carbohydrates within the wheat leaf. In plants grown in the presence of nitrate there was reduced levels of a number of sugar metabolites in the leaf base and an increase in maltose levels, possibly reflecting an increase in starch turnover. The value of using this combined metabolomics analysis for further functional investigations in the future are discussed. PMID:25680480

  12. Comparative studies of S-layer proteins from Bacillus stearothermophilus strains expressed during growth in continuous culture under oxygen-limited and non-oxygen-limited conditions.

    PubMed Central

    Sára, M; Sleytr, U B

    1994-01-01

    The specific properties of S-layer proteins from three different Bacillus stearothermophilus strains revealing oblique, square, or hexagonal lattice symmetry were preserved during growth in continuous culture on complex medium only under oxygen-limited conditions in which glucose was used as the sole carbon source. When oxygen limitation was relieved, amino acids became metabolized, cell density increased, and different S-layer proteins from wild-type strains became rapidly replaced by a new common type of S-layer protein with an apparent subunit molecular weight of 97,000 which assembled into an identical oblique (p2) lattice type. During switching from wild-type strains to variants, patches of the S-layer lattices characteristics for wild-type strains, granular regions, and areas with oblique lattice symmetry could be observed on the surface of individual cells from all organisms. The granular regions apparently consisted of mixtures of the S-layer proteins from the wild-type strains and the newly synthesized p2 S-layer proteins from the variants. S-layer proteins from wild-type strains possessed identical N-terminal regions but led to quite different cleavage products upon peptide mapping, indicating that they are encoded by different genes. Chemical analysis including N-terminal sequencing and peptide mapping showed that the oblique S-layer lattices synthesized under increased oxygen supply were composed of identical protein species. Images PMID:7961489

  13. The capacity of Porphyromonas gingivalis to multiply under iron-limiting conditions correlates with its pathogenicity in an animal model.

    PubMed

    Grenier, D; Goulet, V; Mayrand, D

    2001-07-01

    Isolates of Porphyromonas gingivalis have various abilities to induce infections in an animal model. The hypothesis of this study was that pathogenic strains of P. gingivalis could multiply under iron-limiting conditions, while non-pathogenic strains could not. Three pathogenic strains (W50, W83, and ATCC 49417) grew to a final optical density (660 nm) > 2 in horse serum, while the growth of the 3 non-pathogenic strains (ATCC 33277, LB13D-2, and HW24D-1) was negligible. When an excess of hemin or ferric chloride was added to the serum, significant growth of the non-pathogenic strains occurred. Under iron-limiting conditions, the pathogenic strains of P. gingivalis had a much lower requirement for human iron-loaded transferrin and hemin than the non-pathogenic strains. Proteolytic degradation of transferrin, which may be associated with the release of iron, was not markedly different for pathogenic and non-pathogenic strains. In addition, no relationship could be established between the level of 55Fe uptake from 55Fe-transferrin and the pathogenicity of strains. Our study provided evidence that the ability of P. gingivalis to multiply in vitro under iron-limiting conditions may be correlated with its ability to induce infections in an animal model. Isolates of P. gingivalis possessing a low requirement for iron are likely to have a higher potential for initiating periodontal infections.

  14. Arsenic-induced phosphate limitation under experimental Early Proterozoic oceanic conditions

    NASA Astrophysics Data System (ADS)

    Chi Fru, Ernest; Hemmingsson, Christoffer; Holm, Mikaela; Chiu, Beverly; Iñiguez, Enrique

    2016-01-01

    Comparison of phosphorus concentrations associated with modern hydrothermal Fe(III)(oxyhydr)oxides and ancient Fe(III) oxide-rich iron formations, is used to estimate bioavailable Precambrian marine phosphorus (P) concentrations. This led to the proposition of a low dissolved P budget of ∼10-25% of present-day levels, before ∼1.9 billion years ago. Estimates incorporating ancient marine Si levels ≥ 0.67 mM instead suggested global dissolved P levels greater than today. Here we unite current experimental models that have considered NaCl solutions containing elevated dissolved Fe(II), Si, Ca2+ and Mg2+ ions in the incorporation of P in Precambrian marine Fe(III)(oxyhydr)oxides, in addition to arsenic as a hydrothermal proxy. We show that the coprecipitation of dissolved P and Fe(III)(oxyhydr)oxides from arsenic-rich marine waters produces an average P distribution coefficient of ∼0.072 (± 0.01) μM-1. This is comparable to the ∼ 0.07 μM-1 predicted for Fe(III)(oxyhydr)oxides in modern arsenic-rich, submarine hydrothermal settings, from which the lower Early Proterozoic dissolved marine P concentrations were predicted. As/P molar ratios below modern seawater ratios removed the negative feedback effect high Si impose on P scavenging by Fe(III)(oxyhydr)oxides. The binding of As(III) to Fe(III)(oxyhydr)oxides exhibits a lower competitive influence on P fixation. As(V) that likely became prominent in the surficially oxidized Early Proterozoic oceans induced dissolved P limitation because of preferential P sequestration at the expense of dissolved As(V) enrichment. The control of As on P scavenging by the precipitating Fe(III)(oxyhydr)oxides is strong regardless of common seawater cations (Mg2+ and Ca2+). The data suggest that the application of Si and Fe(III)(oxyhydr)oxides as an ancient seawater P proxy should consider chemical variability between depositional basins, taking into account the rather strong role hydrothermal arsenic has on the distribution of P

  15. Finding Mutual Exclusion Invariants in Temporal Planning Domains

    NASA Technical Reports Server (NTRS)

    Bernardini, Sara; Smith, David E.

    2011-01-01

    We present a technique for automatically extracting temporal mutual exclusion invariants from PDDL2.2 planning instances. We first identify a set of invariant candidates by inspecting the domain and then check these candidates against properties that assure invariance. If these properties are violated, we show that it is sometimes possible to refine a candidate by adding additional propositions and turn it into a real invariant. Our technique builds on other approaches to invariant synthesis presented in the literature, but departs from their limited focus on instantaneous discrete actions by addressing temporal and numeric domains. To deal with time, we formulate invariance conditions that account for both the entire structure of the operators (including the conditions, rather than just the effects) and the possible interactions between operators. As a result, we construct a technique that is not only capable of identifying invariants for temporal domains, but is also able to find a broader set of invariants for non-temporal domains than the previous techniques.

  16. Benefits and limitations of pig slurry to reclaim bare mine soils under Mediterranean semiarid conditions

    NASA Astrophysics Data System (ADS)

    Zornoza, Raúl; Faz, Ángel; Acosta, Jose A.; Kabas, Sebla; Martínez-Martínez, Silvia; Ángeles Muñoz, M.

    2013-04-01

    In this study, the effects of pig slurry application on reclamation of mine soils from Cartagena-La Unión Mining District (SE Spain) were investigated in a field experiment. Exchangeable metals (Cd, Cu, Pb and Zn), total organic carbon, total nitrogen, soluble carbon, microbial biomass and three enzyme activities were periodically monitored during 67 days. In addition, one year after the application of the pig slurry, soil and developed vegetation was sampled. Results showed that only exchangeable Cd and Zn significantly decreased in the amended plots, mainly for Cd, with decreases of 98%. The rest of metals and chemical properties did not change with time after application of amendments, showing values not significantly different than those present before pig slurry application. Soluble carbon, microbial biomass carbon and the enzyme activities increased after the application of pig slurry. However, after various days these parameters started a decreasing trend until reaching values similar to the control from approximately day 25. Thus, mainly precipitation as phosphate from the waste was very effective for Cd immobilization. No increments were observed in soil organic carbon because the organic carbon applied with the slurry was too low to be significantly detected. Nonetheless, pig slurry is a good fertilizer owing to the high quantity of nutrients provided, needed to promote the development of vegetation. One year after application, a native vegetation cover (25-30%) was reached by spontaneous colonization. Triggered plant growth by the effect of amendment improved soil conditions, particularly by the help of the medium created by their rhizosphere systems. Increments in soil organic carbon and total nitrogen, and decreases in the exchangeable metals fraction concentration were observed in rhizospheric soils when compared to the bare soils. This improvement in soil quality mediated by vegetation was more efficient than the direct effect of the amendment. In

  17. Defense mutualisms enhance plant diversification

    PubMed Central

    Weber, Marjorie G.; Agrawal, Anurag A.

    2014-01-01

    The ability of plants to form mutualistic relationships with animal defenders has long been suspected to influence their evolutionary success, both by decreasing extinction risk and by increasing opportunity for speciation through an expanded realized niche. Nonetheless, the hypothesis that defense mutualisms consistently enhance plant diversification across lineages has not been well tested due to a lack of phenotypic and phylogenetic information. Using a global analysis, we show that the >100 vascular plant families in which species have evolved extrafloral nectaries (EFNs), sugar-secreting organs that recruit arthropod mutualists, have twofold higher diversification rates than families that lack species with EFNs. Zooming in on six distantly related plant clades, trait-dependent diversification models confirmed the tendency for lineages with EFNs to display increased rates of diversification. These results were consistent across methodological approaches. Inference using reversible-jump Markov chain Monte Carlo (MCMC) to model the placement and number of rate shifts revealed that high net diversification rates in EFN clades were driven by an increased number of positive rate shifts following EFN evolution compared with sister clades, suggesting that EFNs may be indirect facilitators of diversification. Our replicated analysis indicates that defense mutualisms put lineages on a path toward increased diversification rates within and between clades, and is concordant with the hypothesis that mutualistic interactions with animals can have an impact on deep macroevolutionary patterns and enhance plant diversity. PMID:25349406

  18. Exploring the Limits of Cell Adhesion under Shear Stress within Physiological Conditions and beyond on a Chip

    PubMed Central

    Stamp, Melanie E. M.; Jötten, Anna M.; Kudella, Patrick W.; Breyer, Dominik; Strobl, Florian G.; Geislinger, Thomas M.; Wixforth, Achim; Westerhausen, Christoph

    2016-01-01

    Cell adhesion processes are of ubiquitous importance for biomedical applications such as optimization of implant materials. Here, not only physiological conditions such as temperature or pH, but also topographical structures play crucial roles, as inflammatory reactions after surgery can diminish osseointegration. In this study, we systematically investigate cell adhesion under static, dynamic and physiologically relevant conditions employing a lab-on-a-chip system. We screen adhesion of the bone osteosarcoma cell line SaOs-2 on a titanium implant material for pH and temperature values in the physiological range and beyond, to explore the limits of cell adhesion, e.g., for feverish and acidic conditions. A detailed study of different surface roughness Rq gives insight into the correlation between the cells’ abilities to adhere and withstand shear flow and the topography of the substrates, finding a local optimum at Rq = 22 nm. We use shear stress induced by acoustic streaming to determine a measure for the ability of cell adhesion under an external force for various conditions. We find an optimum of cell adhesion for T = 37 °C and pH = 7.4 with decreasing cell adhesion outside the physiological range, especially for high T and low pH. We find constant detachment rates in the physiological regime, but this behavior tends to collapse at the limits of 41 °C and pH 4. PMID:27775638

  19. Exploring the Limits of Cell Adhesion under Shear Stress within Physiological Conditions and beyond on a Chip.

    PubMed

    Stamp, Melanie E M; Jötten, Anna M; Kudella, Patrick W; Breyer, Dominik; Strobl, Florian G; Geislinger, Thomas M; Wixforth, Achim; Westerhausen, Christoph

    2016-10-21

    Cell adhesion processes are of ubiquitous importance for biomedical applications such as optimization of implant materials. Here, not only physiological conditions such as temperature or pH, but also topographical structures play crucial roles, as inflammatory reactions after surgery can diminish osseointegration. In this study, we systematically investigate cell adhesion under static, dynamic and physiologically relevant conditions employing a lab-on-a-chip system. We screen adhesion of the bone osteosarcoma cell line SaOs-2 on a titanium implant material for pH and temperature values in the physiological range and beyond, to explore the limits of cell adhesion, e.g., for feverish and acidic conditions. A detailed study of different surface roughness Rq gives insight into the correlation between the cells' abilities to adhere and withstand shear flow and the topography of the substrates, finding a local optimum at Rq = 22 nm. We use shear stress induced by acoustic streaming to determine a measure for the ability of cell adhesion under an external force for various conditions. We find an optimum of cell adhesion for T = 37 °C and pH = 7.4 with decreasing cell adhesion outside the physiological range, especially for high T and low pH. We find constant detachment rates in the physiological regime, but this behavior tends to collapse at the limits of 41 °C and pH 4.

  20. Doppler-broadened NICE-OHMS beyond the cavity-limited weak absorption condition - II: Experimental verification

    NASA Astrophysics Data System (ADS)

    Hausmaninger, Thomas; Silander, Isak; Ma, Weiguang; Axner, Ove

    2016-01-01

    Doppler-broadened (Db) noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) is normally described by an expression, here termed the conventional (CONV) description, that is restricted to the conventional cavity-limited weak absorption condition (CCLWA), i.e. when the single pass absorbance is significantly smaller than the empty cavity losses, i.e. when α0 L < < π / F. To describe NICE-OHMS signals beyond this limit two simplified extended descriptions (termed the extended locking and extended transmission description, ELET, and the extended locking and full transmission description, ELFT), which are assumed to be valid under the relaxed cavity-limited weak absorption condition (RCLWA), i.e. when α0 L < π / F, and a full description (denoted FULL), presumed to be valid also when the α0 L < π / F condition does not hold, have recently been derived in an accompanying work (Ma W, et al. Doppler-broadened NICE-OHMS beyond the cavity-limited weak absorption condition - I. Theoretical Description. J Quant Spectrosc Radiat Transfer, 2015, http://dx.doi.org/10.1016/j.jqsrt.2015.09.007). The present work constitutes an experimental verification and assessment of the validity of these, performed in the Doppler limit for a set of Fα0 L / π values (up to 3.5); it is shown under which conditions the various descriptions are valid. It is concluded that for samples with Fα0 L / π up to 0.01, all descriptions replicate the data well. It is shown that the CONV description is adequate and provides accurate assessments of the signal strength (and thereby the analyte concentration) up to Fα0 L / π of around 0.1, while the ELET is accurate for Fα0 L / π up to around 0.3. The ELFT description mimics the Db NICE-OHMS signal well for Fα0 L / π up to around unity, while the FULL description is adequate for all Fα0 L / π values investigated. Access to these descriptions both increases considerably the dynamic range of the technique and

  1. Hypoxic areas, density-dependence and food limitation drive the body condition of a heavily exploited marine fish predator

    PubMed Central

    Käll, Filip; Hansson, Martin; Baranova, Tatjana; Karlsson, Olle; Lundström, Karl; Neuenfeldt, Stefan; Hjelm, Joakim

    2016-01-01

    Investigating the factors regulating fish condition is crucial in ecology and the management of exploited fish populations. The body condition of cod (Gadus morhua) in the Baltic Sea has dramatically decreased during the past two decades, with large implications for the fishery relying on this resource. Here, we statistically investigated the potential drivers of the Baltic cod condition during the past 40 years using newly compiled fishery-independent biological data and hydrological observations. We evidenced a combination of different factors operating before and after the ecological regime shift that occurred in the Baltic Sea in the early 1990s. The changes in cod condition related to feeding opportunities, driven either by density-dependence or food limitation, along the whole period investigated and to the fivefold increase in the extent of hypoxic areas in the most recent 20 years. Hypoxic areas can act on cod condition through different mechanisms related directly to species physiology, or indirectly to behaviour and trophic interactions. Our analyses found statistical evidence for an effect of the hypoxia-induced habitat compression on cod condition possibly operating via crowding and density-dependent processes. These results furnish novel insights into the population dynamics of Baltic Sea cod that can aid the management of this currently threatened population. PMID:27853557

  2. Mutually-antagonistic interactions in baseball networks

    NASA Astrophysics Data System (ADS)

    Saavedra, Serguei; Powers, Scott; McCotter, Trent; Porter, Mason A.; Mucha, Peter J.

    2010-03-01

    We formulate the head-to-head matchups between Major League Baseball pitchers and batters from 1954 to 2008 as a bipartite network of mutually-antagonistic interactions. We consider both the full network and single-season networks, which exhibit structural changes over time. We find interesting structure in the networks and examine their sensitivity to baseball’s rule changes. We then study a biased random walk on the matchup networks as a simple and transparent way to (1) compare the performance of players who competed under different conditions and (2) include information about which particular players a given player has faced. We find that a player’s position in the network does not correlate with his placement in the random walker ranking. However, network position does have a substantial effect on the robustness of ranking placement to changes in head-to-head matchups.

  3. Fragile X Mental Retardation Protein Is Required to Maintain Visual Conditioning-Induced Behavioral Plasticity by Limiting Local Protein Synthesis

    PubMed Central

    Liu, Han-Hsuan

    2016-01-01

    Fragile X mental retardation protein (FMRP) is thought to regulate neuronal plasticity by limiting dendritic protein synthesis, but direct demonstration of a requirement for FMRP control of local protein synthesis during behavioral plasticity is lacking. Here we tested whether FMRP knockdown in Xenopus optic tectum affects local protein synthesis in vivo and whether FMRP knockdown affects protein synthesis-dependent visual avoidance behavioral plasticity. We tagged newly synthesized proteins by incorporation of the noncanonical amino acid azidohomoalanine and visualized them with fluorescent noncanonical amino acid tagging (FUNCAT). Visual conditioning and FMRP knockdown produce similar increases in FUNCAT in tectal neuropil. Induction of visual conditioning-dependent behavioral plasticity occurs normally in FMRP knockdown animals, but plasticity degrades over 24 h. These results indicate that FMRP affects visual conditioning-induced local protein synthesis and is required to maintain the visual conditioning-induced behavioral plasticity. SIGNIFICANCE STATEMENT Fragile X syndrome (FXS) is the most common form of inherited intellectual disability. Exaggerated dendritic protein synthesis resulting from loss of fragile X mental retardation protein (FMRP) is thought to underlie cognitive deficits in FXS, but no direct evidence has demonstrated that FMRP-regulated dendritic protein synthesis affects behavioral plasticity in intact animals. Xenopus tadpoles exhibit a visual avoidance behavior that improves with visual conditioning in a protein synthesis-dependent manner. We showed that FMRP knockdown and visual conditioning dramatically increase protein synthesis in neuronal processes. Furthermore, induction of visual conditioning-dependent behavioral plasticity occurs normally after FMRP knockdown, but performance rapidly deteriorated in the absence of FMRP. These studies show that FMRP negatively regulates local protein synthesis and is required to maintain visual

  4. Utilizing Mutual Aid in Reducing Adolescent Substance Use and Developing Group Engagement

    ERIC Educational Resources Information Center

    Mogro-Wilson, Cristina; Letendre, Joan; Toi, Hiroki; Bryan, Janelle

    2015-01-01

    Objective: This study assessed the effectiveness of mutual aid groups for high school students. Methods: A quasi-experimental design was applied to 242 adolescents, where every other adolescent was assigned to the intervention or the control condition. The study evaluated the influence of implementing mutual aid groups in decreasing perceived risk…

  5. Towards lag phase of microbial populations at growth-limiting conditions: The role of the variability in the growth limits of individual cells.

    PubMed

    Aguirre, Juan S; Koutsoumanis, Konstantinos P

    2016-05-02

    The water activity (aw) growth limits of unheated and heat stressed Listeria monocytogenes individual cells were studied. The aw limits varied from 0.940 to 0.997 and 0.951 to 0.997 for unheated and heat stressed cells, respectively. Due to the above variability a decrease in aw results in the presence of a non-growing fraction in the population leading to an additional pseudo-lag in population growth. In this case the total apparent lag of the population is the sum of the physiological lag of the growing cells (time required to adjust to the new environment) and the pseudo-lag. To investigate the effect of aw on the above lag components, the growth kinetics of L. monocytogenes on tryptone soy agar with aw adjusted to values ranging from 0.997 to 0.940 was monitored. The model of B&R was fitted to the data for the estimation of the apparent lag. In order to estimate the physiological lag of the growing fraction of the inoculum, the model was refitted to the growth data using as initial population level the number of cells that were able to grow (estimated from the number of colonies formed on the agar at the end of storage) and excluding the rest data during the lag. The results showed that for the unheated cells the apparent lag was almost identical to the physiological lag for aw values ranging from 0.997 to 0.970, as the majority of the cells in the initial population was able to grow in these conditions. As the aw decreased from 0.970 to 0.940 however, the number of cells in the population which were able to grow, decreased resulting to an increase in the pseudo-lag. The maximum value of pseudo-lag was 13.1h and it was observed at aw=0.940 where 10% of the total inoculated cells were able to grow. For heat stressed populations a pseudo-lag started to increase at higher aw conditions (0.982) compared to unheated cells. In contrast to the apparent lag, a linear relation between physiological lag and aw was observed for both unheated and heat stressed cells.

  6. Oil viscosity limitation on dispersibility of crude oil under simulated at-sea conditions in a large wave tank.

    PubMed

    Trudel, Ken; Belore, Randy C; Mullin, Joseph V; Guarino, Alan

    2010-09-01

    This study determined the limiting oil viscosity for chemical dispersion of oil spills under simulated sea conditions in the large outdoor wave tank at the US National Oil Spill Response Test Facility in New Jersey. Dispersant effectiveness tests were completed using crude oils with viscosities ranging from 67 to 40,100 cP at test temperature. Tests produced an effectiveness-viscosity curve with three phases when oil was treated with Corexit 9500 at a dispersant-to-oil ratio of 1:20. The oil viscosity that limited chemical dispersion under simulated at-sea conditions was in the range of 18,690 cP to 33,400 cP. Visual observations and measurements of oil concentrations and droplet size distributions in the water under treated and control slicks correlated well with direct measurements of effectiveness. The dispersant effectiveness versus oil viscosity relationship under simulated at sea conditions at Ohmsett was most similar to those from similar tests made using the Institut Francais du Pétrole and Exxon Dispersant Effectiveness (EXDET) test methods.

  7. Physiology of Geobacter metallireducens under excess and limitation of electron donors. Part II. Mimicking environmental conditions during cultivation in retentostats.

    PubMed

    Marozava, Sviatlana; Röling, Wilfred F M; Seifert, Jana; Küffner, Robert; von Bergen, Martin; Meckenstock, Rainer U

    2014-06-01

    The strict anaerobe Geobacter metallireducens was cultivated in retentostats under acetate and acetate plus benzoate limitation in the presence of Fe(III) citrate in order to investigate its physiology under close to natural conditions. Growth rates below 0.003h(-1) were achieved in the course of cultivation. A nano-liquid chromatography-tandem mass spectrometry-based proteomic approach (nano-LC-MS/MS) with subsequent label-free quantification was performed on proteins extracted from cells sampled at different time points during retentostat cultivation. Proteins detected at low (0.002h(-1)) and high (0.06h(-1)) growth rates were compared between corresponding growth conditions (acetate or acetate plus benzoate). Carbon limitation significantly increased the abundances of several catabolic proteins involved in the degradation of substrates not present in the medium (ethanol, butyrate, fatty acids, and aromatic compounds). Growth rate-specific physiology was reflected in the changed abundances of energy-, chemotaxis-, oxidative stress-, and transport-related proteins. Mimicking natural conditions by extremely slow bacterial growth allowed to show how G. metallireducens optimized its physiology in order to survive in its natural habitats, since it was prepared to consume several carbon sources simultaneously and to withstand various environmental stresses.

  8. The behavior of fuel-lean premixed flames in a standard flammability limit tube under controlled gravity conditions

    NASA Technical Reports Server (NTRS)

    Wherley, B. L.; Strehlow, R. A.

    1986-01-01

    Fuel-lean flames in methane-air mixtures from 4.90 to 6.20 volume percent fuel and propane-air mixtures from 1.90 to 3.00 volume percent fuel were studied in the vicinity of the limit for a variety of gravity conditions. The limits were determined and the behavior of the flames studied for one g upward, one g downward, and zero g propagation. Photographic records of all flammability tube firings were obtained. The structure and behavior of these flames were detailed including the variations of the curvature of the flame front, the skirt length, and the occurrence of cellular instabilities with varying gravity conditions. The effect of ignition was also discussed. A survey of flame speeds as a function of mixture strength was made over a range of lean mixture compositions for each of the fuels studied. The results were presented graphically with those obtained by other researchers. The flame speed for constant fractional gravity loadings were plotted as a function of gravity loadings from 0.0 up to 2.0 g's against flame speeds extracted from the transient gravity flame histories for corresponding gravity loadings. The effects of varying gravity conditions on the extinguishment process for upward and downward propagating flames were investigated.

  9. Impact of Australian Dekkera bruxellensis strains grown under oxygen-limited conditions on model wine composition and aroma.

    PubMed

    Curtin, Chris D; Langhans, Geoffrey; Henschke, Paul A; Grbin, Paul R

    2013-12-01

    Spoilage of red wine by the yeast species Dekkera bruxellensis is a common problem for the global wine industry. When conditions are conducive for growth of these yeasts in wine, they efficiently convert non-volatile hydroxycinnamic acids into aroma-active ethylphenols, thereby reducing the quality of the wine. It has been demonstrated previously that dissolved oxygen is a key factor which stimulates D. bruxellensis growth in wine. We demonstrate that whereas the presence of oxygen accelerates the growth of this species, oxygen-limited conditions favour 4-ethylphenol production. Consequently, we evaluated wine spoilage potential of three D. bruxellensis strains (AWRI1499, AWRI1608 and AWRI1613) under oxygen-limited conditions. Each strain was cultured in a chemically-defined wine medium and the fermentation products were analysed using HPLC and HS-SPME-GC/MS. The strains displayed different growth characteristics but were equally capable of producing ethylphenols. On the other hand, significant differences were observed for 18 of the remaining 33 metabolites analysed and duo-trio sensory analysis indicated significant aroma differences between wines inoculated with AWRI1499 and AWRI1613. When these wines were spiked with low concentrations of 4-ethylphenol and 4-ethylguaiacol, no sensorial differences could be perceived. Together these data suggest that the three predominant D. bruxellensis strains previously isolated during a large survey of Australian wineries do not differ substantively in their capacity to grow in, and spoil, a model wine medium.

  10. 26 CFR 1.831-1 - Tax on insurance companies (other than life or mutual), mutual marine insurance companies, and...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... mutual), mutual marine insurance companies, and mutual fire insurance companies issuing perpetual policies. 1.831-1 Section 1.831-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... insurance companies (other than life or mutual), mutual marine insurance companies, and mutual...

  11. 26 CFR 1.831-1 - Tax on insurance companies (other than life or mutual), mutual marine insurance companies, and...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... mutual), mutual marine insurance companies, and mutual fire insurance companies issuing perpetual policies. 1.831-1 Section 1.831-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... insurance companies (other than life or mutual), mutual marine insurance companies, and mutual...

  12. Impaired growth under iron-limiting conditions associated with the acquisition of colistin resistance in Acinetobacter baumannii.

    PubMed

    López-Rojas, Rafael; García-Quintanilla, Meritxell; Labrador-Herrera, Gema; Pachón, Jerónimo; McConnell, Michael J

    2016-06-01

    Acquisition of colistin resistance in Acinetobacter baumannii has been associated with reduced bacterial fitness and virulence, although the mechanisms underlying this fitness loss have not been well characterised. In this study, the role played by environmental iron levels on the growth and survival of colistin-resistant strains of A. baumannii was assessed. Growth assays with the colistin-susceptible ATCC 19606 strain and its colistin-resistant derivative RC64 [colistin minimum inhibitory concentration (MIC) of 64 mg/L] demonstrated that the strains grew similarly in rich laboratory medium (Mueller-Hinton broth), whereas RC64 demonstrated impaired growth compared with ATCC 19606 in human serum (>100-fold at 24 h). Compared with RC64, ATCC 19606 grew in the presence of higher concentrations of the iron-specific chelator 2,2'-bipyridine and grew more readily under iron-limiting conditions in solid and liquid media. In addition, iron supplementation of human serum increased the growth of RC64 compared with unsupplemented human serum to a greater extent than ATCC 19606. The ability of 11 colistin-resistant clinical isolates with mutations in the pmrB gene to grow in iron-replete and iron-limiting conditions was assessed, demonstrating that eight of the strains showed reduced growth under iron limitation. Individual mutations in the pmrB gene did not directly correlate with a decreased capacity for growth under iron limitation, suggesting that mutations in pmrB may not directly produce this phenotype. Together these results indicate that acquisition of colistin resistance in A. baumannii can be associated with a decreased ability to grow in low-iron environments.

  13. Fe and P solubilization under limiting conditions by bacteria isolated from Carex kobomugi roots at the Hasaki coast.

    PubMed

    Matsuoka, Hiroaki; Akiyama, Masaru; Kobayashi, Katsuichiro; Yamaji, Keiko

    2013-03-01

    Our objective was simply to report a sedge species, Carex kobomugi Ohwi that has beneficial bacterial associations under low Fe and P conditions of the Hasaki coast, Japan. C. kobomugi is the dominant species in our study area and grows closest to the sea. C. kobomugi showed higher Fe and P content, while these nutrients were less available under alkaline root-zone soil. Within the roots, mycorrhizal fungal colonization was absent, and endophytic fungal colonization was low. On the contrary, endophytic bacteria (e.g. Bacillus sp., Streptomyces luteogriseus, and Pseudomonas fluorescens) were isolated, which exhibited both siderophore production and inorganic phosphate solubilization under Fe or P limited conditions. Our results suggest that colonization of root tissue by these bacteria contribute to the Fe and P uptakes by C. kobomugi by increasing availability in the soil.

  14. Dekkera/Brettanomyces yeasts for ethanol production from renewable sources under oxygen-limited and low-pH conditions.

    PubMed

    Galafassi, Silvia; Merico, Annamaria; Pizza, Francesca; Hellborg, Linda; Molinari, Francesco; Piškur, Jure; Compagno, Concetta

    2011-08-01

    Industrial fermentation of lignocellulosic hydrolysates to ethanol requires microorganisms able to utilise a broad range of carbon sources and generate ethanol at high yield and productivity. D. bruxellensis has recently been reported to contaminate commercial ethanol processes, where it competes with Saccharomyces cerevisiae [4, 26]. In this work Brettanomyces/Dekkera yeasts were studied to explore their potential to produce ethanol from renewable sources under conditions suitable for industrial processes, such as oxygen-limited and low-pH conditions. Over 50 strains were analysed for their ability to utilise a variety of carbon sources, and some strains grew on cellobiose and pentoses. Two strains of D. bruxellensis were able to produce ethanol at high yield (0.44 g g(-1) glucose), comparable to those reported for S. cerevisiae. B. naardenensis was shown to be able to produce ethanol from xylose. To obtain ethanol from synthetic lignocellulosic hydrolysates we developed a two-step fermentation strategy: the first step under aerobic conditions for fast production of biomass from mixtures of hexoses and pentoses, followed by a second step under oxygen limitation to promote ethanol production. Under these conditions we obtained biomass and ethanol production on synthetic lignocellulosic hydrolysates, with ethanol yields ranging from 0.2 to 0.3 g g(-1) sugar. Hexoses, xylose and arabinose were consumed at the end of the process, resulting in 13 g l(-1) of ethanol, even in the presence of furfural. Our studies showed that Brettanomyces/Dekkera yeasts have clear potential for further development for industrial processes aimed at production of ethanol from renewable sources.

  15. 26 CFR 1.831-3 - Tax on insurance companies (other than life or mutual), mutual marine insurance companies, mutual...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... business within the United States, and all mutual marine insurance companies and mutual fire or flood insurance companies exclusively issuing perpetual policies or whose principal business is the issuance of...) Foreign insurance companies not carrying on an insurance business within the United States are not...

  16. 26 CFR 1.831-3 - Tax on insurance companies (other than life or mutual), mutual marine insurance companies, mutual...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... insurance business within the United States, and all mutual marine insurance companies and mutual fire or flood insurance companies exclusively issuing perpetual policies or whose principal business is the...) Foreign insurance companies not carrying on an insurance business within the United States are not...

  17. 26 CFR 1.831-3 - Tax on insurance companies (other than life or mutual), mutual marine insurance companies, mutual...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 8 2014-04-01 2014-04-01 false Tax on insurance companies (other than life or... beginning after December 31, 1962. 1.831-3 Section 1.831-3 Internal Revenue INTERNAL REVENUE SERVICE... Companies § 1.831-3 Tax on insurance companies (other than life or mutual), mutual marine...

  18. 26 CFR 1.831-3 - Tax on insurance companies (other than life or mutual), mutual marine insurance companies, mutual...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 8 2013-04-01 2013-04-01 false Tax on insurance companies (other than life or... beginning after December 31, 1962. 1.831-3 Section 1.831-3 Internal Revenue INTERNAL REVENUE SERVICE... Companies § 1.831-3 Tax on insurance companies (other than life or mutual), mutual marine...

  19. Abnormal functional connectivity in focal hand dystonia: mutual information analysis in EEG.

    PubMed

    Jin, Seung-Hyun; Lin, Peter; Auh, Sungyoung; Hallett, Mark

    2011-06-01

    The aim of the present study was to investigate functional connectivity in focal hand dystonia patients to understand the pathophysiology underlying their abnormality in movement. We recorded EEGs from 58 electrodes in 15 focal hand dystonia patients and 15 healthy volunteers during rest and a simple finger-tapping task that did not induce any dystonic symptoms. We investigated mutual information, which provides a quantitative measure of linear and nonlinear coupling, in the alpha, beta, and gamma bands. Mean mutual information of all 58 channels and mean of the channels of interest representative of regional functional connectivity over sensorimotor areas (C3, CP3, C4, CP4, FCz, and Cz) were evaluated. For both groups, we found enhanced mutual information during the task compared with the rest condition, specifically in the beta and gamma bands for mean mutual information of all channels, and in all bands for mean mutual information of channels of interest. Comparing the focal hand dystonia patients with the healthy volunteers for both rest and task, there was reduced mutual information in the beta band for both mean mutual information of all channels and mean mutual information of channels of interest. Regarding the properties of the connectivity in the beta band, we found that the majority of the mutual information differences were from linear connectivity. The abnormal beta-band functional connectivity in focal hand dystonia patients suggests deficient brain connectivity.

  20. Oxygen Response of the Wine Yeast Saccharomyces cerevisiae EC1118 Grown under Carbon-Sufficient, Nitrogen-Limited Enological Conditions

    PubMed Central

    Aceituno, Felipe F.; Orellana, Marcelo; Torres, Jorge; Mendoza, Sebastián; Slater, Alex W.; Melo, Francisco

    2012-01-01

    Discrete additions of oxygen play a critical role in alcoholic fermentation. However, few studies have quantitated the fate of dissolved oxygen and its impact on wine yeast cell physiology under enological conditions. We simulated the range of dissolved oxygen concentrations that occur after a pump-over during the winemaking process by sparging nitrogen-limited continuous cultures with oxygen-nitrogen gaseous mixtures. When the dissolved oxygen concentration increased from 1.2 to 2.7 μM, yeast cells changed from a fully fermentative to a mixed respirofermentative metabolism. This transition is characterized by a switch in the operation of the tricarboxylic acid cycle (TCA) and an activation of NADH shuttling from the cytosol to mitochondria. Nevertheless, fermentative ethanol production remained the major cytosolic NADH sink under all oxygen conditions, suggesting that the limitation of mitochondrial NADH reoxidation is the major cause of the Crabtree effect. This is reinforced by the induction of several key respiratory genes by oxygen, despite the high sugar concentration, indicating that oxygen overrides glucose repression. Genes associated with other processes, such as proline uptake, cell wall remodeling, and oxidative stress, were also significantly affected by oxygen. The results of this study indicate that respiration is responsible for a substantial part of the oxygen response in yeast cells during alcoholic fermentation. This information will facilitate the development of temporal oxygen addition strategies to optimize yeast performance in industrial fermentations. PMID:23001663

  1. Conditional solvation thermodynamics of isoleucine in model peptides and the limitations of the group-transfer model.

    PubMed

    Tomar, Dheeraj S; Weber, Valéry; Pettitt, B Montgomery; Asthagiri, D

    2014-04-17

    The hydration thermodynamics of the amino acid X relative to the reference G (glycine) or the hydration thermodynamics of a small-molecule analog of the side chain of X is often used to model the contribution of X to protein stability and solution thermodynamics. We consider the reasons for successes and limitations of this approach by calculating and comparing the conditional excess free energy, enthalpy, and entropy of hydration of the isoleucine side chain in zwitterionic isoleucine, in extended penta-peptides, and in helical deca-peptides. Butane in gauche conformation serves as a small-molecule analog for the isoleucine side chain. Parsing the hydrophobic and hydrophilic contributions to hydration for the side chain shows that both of these aspects of hydration are context-sensitive. Furthermore, analyzing the solute-solvent interaction contribution to the conditional excess enthalpy of the side chain shows that what is nominally considered a property of the side chain includes entirely nonobvious contributions of the background. The context-sensitivity of hydrophobic and hydrophilic hydration and the conflation of background contributions with energetics attributed to the side chain limit the ability of a single scaling factor, such as the fractional solvent exposure of the group in the protein, to map the component energetic contributions of the model-compound data to their value in the protein. But ignoring the origin of cancellations in the underlying components the group-transfer model may appear to provide a reasonable estimate of the free energy for a given error tolerance.

  2. Pyruvate and lactate metabolism by Shewanella oneidensis MR-1 under fermentation, oxygen limitation, and fumarate respiration conditions.

    PubMed

    Pinchuk, Grigoriy E; Geydebrekht, Oleg V; Hill, Eric A; Reed, Jennifer L; Konopka, Allan E; Beliaev, Alexander S; Fredrickson, Jim K

    2011-12-01

    Shewanella oneidensis MR-1 is a facultative anaerobe that derives energy by coupling organic matter oxidation to the reduction of a wide range of electron acceptors. Here, we quantitatively assessed the lactate and pyruvate metabolism of MR-1 under three distinct conditions: electron acceptor-limited growth on lactate with O(2), lactate with fumarate, and pyruvate fermentation. The latter does not support growth but provides energy for cell survival. Using physiological and genetic approaches combined with flux balance analysis, we showed that the proportion of ATP produced by substrate-level phosphorylation varied from 33% to 72.5% of that needed for growth depending on the electron acceptor nature and availability. While being indispensable for growth, the respiration of fumarate does not contribute significantly to ATP generation and likely serves to remove formate, a product of pyruvate formate-lyase-catalyzed pyruvate disproportionation. Under both tested respiratory conditions, S. oneidensis MR-1 carried out incomplete substrate oxidation, whereby the tricarboxylic acid (TCA) cycle did not contribute significantly. Pyruvate dehydrogenase was not involved in lactate metabolism under conditions of O(2) limitation but was required for anaerobic growth, likely by supplying reducing equivalents for biosynthesis. The results suggest that pyruvate fermentation by S. oneidensis MR-1 cells represents a combination of substrate-level phosphorylation and respiration, where pyruvate serves as an electron donor and an electron acceptor. Pyruvate reduction to lactate at the expense of formate oxidation is catalyzed by a recently described new type of oxidative NAD(P)H-independent d-lactate dehydrogenase (Dld-II). The results further indicate that pyruvate reduction coupled to formate oxidation may be accompanied by the generation of proton motive force.

  3. Basolateral amygdala lesions abolish mutual reward preferences in rats.

    PubMed

    Hernandez-Lallement, Julen; van Wingerden, Marijn; Schäble, Sandra; Kalenscher, Tobias

    2016-01-01

    In a recent study, we demonstrated that rats prefer mutual rewards in a Prosocial Choice Task. Here, employing the same task, we show that the integrity of basolateral amygdala was necessary for the expression of mutual reward preferences. Actor rats received bilateral excitotoxic (n=12) or sham lesions (n=10) targeting the basolateral amygdala and were subsequently tested in a Prosocial Choice Task where they could decide between rewarding ("Both Reward") or not rewarding a partner rat ("Own Reward"), either choice yielding identical reward to the actors themselves. To manipulate the social context and control for secondary reinforcement sources, actor rats were paired with either a partner rat (partner condition) or with an inanimate rat toy (toy condition). Sham-operated animals revealed a significant preference for the Both-Reward-option in the partner condition, but not in the toy condition. Amygdala-lesioned animals exhibited significantly lower Both-Reward preferences than the sham group in the partner but not in the toy condition, suggesting that basolateral amygdala was required for the expression of mutual reward preferences. Critically, in a reward magnitude discrimination task in the same experimental setup, both sham-operated and amygdala-lesioned animals preferred large over small rewards, suggesting that amygdala lesion effects were restricted to decision making in social contexts, leaving self-oriented behavior unaffected.

  4. Preferential depletion of zinc within Costa Rica upwelling dome creates conditions for zinc co-limitation of primary production

    PubMed Central

    Dreux Chappell, P.; Vedmati, Jagruti; Selph, Karen E.; Cyr, Heather A.; Jenkins, Bethany D.; Landry, Michael R.; Moffett, James W.

    2016-01-01

    The Costa Rica Dome (CRD) is a wind-driven feature characterized by high primary production and an unusual cyanobacterial bloom in surface waters. It is not clear whether this bloom arises from top-down or bottom-up processes. Several studies have argued that trace metal geochemistry within the CRD contributes to the composition of the phytoplankton assemblages, since cyanobacteria and eukaryotic phytoplankton have different transition metal requirements. Here, we report that total dissolved zinc (Zn) is significantly depleted relative to phosphate (P) and silicate (Si) within the upper water column of the CRD compared with other oceanic systems, and this may create conditions favorable for cyanobacteria, which have lower Zn requirements than their eukaryotic competitors. Shipboard grow-out experiments revealed that while Si was a limiting factor under our experimental conditions, additions of Si and either iron (Fe) or Zn led to higher biomass than Si additions alone. The addition of Fe and Zn alone did not lead to significant enhancements. Our results suggest that the depletion of Zn relative to P in upwelled waters may create conditions in the near-surface waters that favor phytoplankton with low Zn requirements, including cyanobacteria. PMID:27275028

  5. [Maintaining solidarity: is mutuality the solution?].

    PubMed

    Gevers, J K M; Ploem, M C

    2013-01-01

    Solidarity is essentially the willingness to contribute to the community and its demands, which may even involve contributing more than one is expecting to receive. Another principle is mutuality: this refers to a balance between rights and obligations or between mutual obligations. In its advisory document 'The importance of mutuality......solidarity takes work!', The Dutch Council for Public Health and Health Care underlines the importance of ensuring solidarity within the Dutch health care system, e.g. by encouraging patients to take responsibility for their own health, possibly by introducing elements of mutuality. In our contribution, we comment on the Council's advice. Although we fully agree with the overall conclusion that solidarity should be maintained within the system, we do not see how the introduction of increased mutuality will contribute to this goal.

  6. Functional analysis of mutual behavior in laboratory rats (Rattus norvegicus)

    PubMed Central

    Tan, Lavinia; Hackenberg, Timothy D.

    2015-01-01

    Three pairs of rats were trained to synchronize their lever pressing according to a mutual reinforcement contingency, in which alternating lever presses that fell within a 500-ms window were reinforced with food. In Experiment 1, rats worked in adjacent chambers separated by a transparent barrier, and the effects of the mutual reinforcement contingency were compared to those under yoked-control conditions that provided the same rate of food reinforcement but without the temporal coordination response requirement. In Experiment 2, coordinated behavior was compared with and without a barrier, and across different barrier types: transparent, opaque, wire mesh. In Experiment 3, the effects of social familiarity were assessed by switching partners, enabling a comparison of coordinated behavior with familiar and unfamiliar partners. The overall pattern of results shows that the coordinated behavior of two rats was (a) maintained by mutual reinforcement contingencies, (b) unrelated to the type or presence of a barrier separating the rats, and (c) sufficiently flexible to adjust to the presence and behavior of an unfamiliar partner. Taken as a whole, the study illustrates a promising approach to conceptualizing and analyzing behavioral mechanisms of mutual behavior, an important component of an integrated study of social behavior. PMID:26479279

  7. Periodic solutions and stationary distribution of mutualism models in random environments

    NASA Astrophysics Data System (ADS)

    Zhang, Xinhong; Jiang, Daqing; Alsaedi, Ahmed; Hayat, Tasawar

    2016-10-01

    This paper is concerned with mutualism models in random environments. For the periodic mutualism model disturbed by white noise, using Has'minskii theory of periodic solution, we show that this model admits a nontrivial positive periodic solution. Then sufficient conditions for the existence and global attractivity of the boundary periodic solutions are established. For the mutualism model disturbed by both white noise and telephone noise, sufficient conditions for positive recurrence and the existence of ergodic stationary distribution of the solution are established. Finally, examples are introduced to illustrate the results developed.

  8. A relational understanding of sibling experiences of children with rare life-limiting conditions: findings from a qualitative study.

    PubMed

    Malcolm, Cari; Gibson, Faith; Adams, Sally; Anderson, Gillian; Forbat, Liz

    2014-09-01

    Mucopolysaccharidoses (MPS) and Batten disease are rare life-limiting conditions (LLCs) characterised by progressive and permanent physical and cognitive decline. The impact of such conditions on families, and notably on siblings, has not yet been described or documented. This paper presents data from a UK-wide study that sought to understand the family experience of supporting a child with the rare degenerative LLCs of MPS and Batten disease. The aim of this paper is to report sibling experiences related to these rare degenerative and progressive conditions, in order to inform the future development of supportive interventions. Eight siblings of children with MPS (n = 7) and Batten Disease (n = 1) participated in semi-structured qualitative interviews. A card sort technique was utilised to support and engage the children. Siblings are clearly impacted emotionally, pragmatically and relationally by the ill health of another child in the family. The data indicate four key themes which demonstrate impacts on siblings: perceptions of the condition and its symptoms, impact on daily life, emotional consequences and ways of coping. Siblings often had considerable knowledge of the condition and took on important roles in symptom management. However, these experiences were in the context of managing relationships within the family (often protecting parents from an awareness of how much they knew) and relationships at school (including distraction from learning and being bullied by peers). The data highlight how sibling experiences are generated through a combination of negative disability discourses and support through peers and family members. The data indicate how these features shift as a consequence of witnessing the advancement of their brother's or sister's condition and the emotional sequelae of disease progression. Exploration of siblings' experiences of living with such rare progressive and degenerative LLCs suggest the focus of interventions to support this

  9. Doppler-broadened NICE-OHMS beyond the cavity-limited weak absorption condition - I. Theoretical description

    NASA Astrophysics Data System (ADS)

    Ma, Weiguang; Silander, Isak; Hausmaninger, Thomas; Axner, Ove

    2016-01-01

    Doppler-broadened (Db) noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) is conventionally described by an expression (here referred to as the CONV expression) that is restricted to the case when the single-pass absorbance, α0L, is much smaller than the empty cavity losses, π/F [here termed the conventional cavity-limited weak absorption (CCLWA) condition]. This limits the applicability of the technique, primarily its dynamic range and calibration capability. To remedy this, this work derives extended descriptions of Db NICE-OHMS that are not restricted to the CCLWA condition. First, the general principles of Db NICE-OHMS are scrutinized in some detail. Based solely upon a set of general assumptions, predominantly that it is appropriate to linearize the Beer-Lambert law, that the light is modulated to a triplet, and that the Pound-Drever-Hall sidebands are fully reflected, a general description of Db NICE-OHMS that is not limited to any specific restriction on α0L vs. π/F, here referred to as the FULL description, is derived. However, this description constitutes a set of equations to which no closed form solution has been found. Hence, it needs to be solved numerically (by iterations), which is inconvenient. To circumvent this, for the cases when α0L<π/F but without the requirement that the stronger CCLWA condition needs to be fulfilled, a couple of simplified extended expressions that are expressible in closed analytical form, referred to as the extended locking and extended transmission description, ELET, and the extended locking and full transmission description, ELFT, have been derived. An analysis based on simulations validates the various descriptions and assesses to which extent they agree. It is shown that in the CCLWA limit, all extended descriptions revert to the CONV expression. The latter one deviates though from the extended ones for α0L around and above 0.1π/F. The two simplified extended descriptions agree

  10. Pyruvate and Lactate Metabolism by Shewanella oneidensis MR-1 under Fermentation, Oxygen Limitation, and Fumarate Respiration Conditions

    SciTech Connect

    Pinchuk, Grigoriy E.; Geydebrekht, Oleg V.; Hill, Eric A.; Reed, Jennifer L.; Konopka, Allan; Beliaev, Alex S.; Fredrickson, Jim K.

    2011-12-30

    Shewanella oneidensis MR-1 is a facultative anaerobe growing by coupling organic matter oxidation to reduction of wide range of electron acceptors. Here we quantitatively assessed lactate and pyruvate metabolism of these bacteria under three distinct conditions: electron acceptor limited growth on lactate with O2 and fumarate, and pyruvate fermentation, which does not sustain growth but allows cells to survive for prolonged period. Using physiological and genetic approaches combined with flux balance analysis, we showed that the proportion of ATP produced by substrate-level phosphorylation varied from 33% to 72.5% of all ATP needed for growth depending on the electron acceptor nature and availability. While being indispensible for growth, respiration of fumarate does not contribute much to ATP generation and likely serves to remove formate, a product of pyruvate formate-lyase-catalyzed pyruvate disproportionation. Under both tested respiratory conditions S. oneidensis MR-1 carried out incomplete substrate oxidation, and TCA cycle did not contribute significantly to substrate oxidation. Pyruvate dehydrogenase reaction was not involved in lactate metabolism under O2 limitation, however was important for anaerobic growth probably supplying reducing equivalents for biosynthesis. Unexpectedly, obtained results suggest that pyruvate fermentation by S. oneidensis MR-1 cells represents a combination between substrate-level phosphorylation and a respiratory process, where pyruvate serves as electron donor and electron acceptor. Pyruvate reduction to lactate at the expense of formate oxidation is catalyzed by recently described new type of oxidative NAD(P)H independent D-lactate dehydrogenase (Dld-II). Based on involved enzymes localization we hypothesize that pyruvate reduction coupled to formate oxidation may be accompanied by proton motive force generation.

  11. Pyruvate and Lactate Metabolism by Shewanella oneidensis MR-1 under Fermentation, Oxygen Limitation, and Fumarate Respiration Conditions

    SciTech Connect

    Pinchuk, Grigoriy E.; Geydebrekht, Oleg V.; Hill, Eric A.; Reed, Jennifer L.; Konopka, Allan; Beliaev, Alex S.; Fredrickson, Jim K.

    2011-12-01

    Shewanella oneidensis MR-1 is a facultative anaerobe that derives energy by coupling organic matter oxidation to the reduction of wide range of electron acceptors. Here, we quantitatively assessed lactate and pyruvate metabolism of MR-1 under three distinct conditions: electron acceptor limited growth on lactate with O2; lactate with fumarate; and pyruvate fermentation. The latter does not support growth but provides energy for cell survival. Using physiological and genetic approaches combined with flux balance analysis, we showed that the proportion of ATP produced by substrate-level phosphorylation varied from 33% to 72.5% of that needed for growth depending on the electron acceptor nature and availability. While being indispensible for growth, respiration of fumarate does not contribute significantly to ATP generation and likely serves to remove formate, a product of pyruvate formate-lyase-catalyzed pyruvate disproportionation. Under both tested respiratory conditions S. oneidensis MR-1 carried out incomplete substrate oxidation, whereby the TCA cycle did not contribute significantly. Pyruvate dehydrogenase was not involved in lactate metabolism under O2 limitation but was required for anaerobic growth likely by supplying reducing equivalents for biosynthesis. The results suggest that pyruvate fermentation by S. oneidensis MR-1 cells represents a combination of substrate-level phosphorylation and respiration, where pyruvate serves as electron donor and electron acceptor. Pyruvate reduction to lactate at the expense of formate oxidation is catalyzed by recently described new type of oxidative NAD(P)H independent D-lactate dehydrogenase (Dld-II). The results further indicate that pyruvate reduction coupled to formate oxidation may be accompanied by proton motive force generation.

  12. Non-limiting food conditions for growth and production of the copepod community in a highly productive upwelling zone

    NASA Astrophysics Data System (ADS)

    Escribano, Rubén; Bustos-Ríos, Evelyn; Hidalgo, Pamela; Morales, Carmen E.

    2016-09-01

    Zooplankton production is critical for understanding marine ecosystem dynamics. This work estimates copepod growth and production in the coastal upwelling and coastal transition zones off central-southern Chile (~35 to 37°S) during a 3-year time series (2004, 2005, and 2006) at a fixed shelf station, and from spring-summer spatial surveys during the same period. To estimate copepod production (CP), we used species-biomasses and associated C-specific growth rates from temperature dependent equations (food-saturated) for the dominant species, which we assumed were maximal growth rates (gmax). Using chlorophyll-a concentrations as a proxy for food conditions, we determined a size-dependent half-saturation constant with the Michaelis-Menten equation to derive growth rates (g) under the effect of food limitation. These food-dependent C-specific growth rates were much lower (<0.1 d-1) than those observed in the field for the dominant species, while gmax for same species, in the range of 0.19-0.23 d-1 better represented the necessary growth to attain observed adult sizes of at least two copepods, Paracalanus cf. indicus and Calanus chilensis. Copepod biomass (CB) and rates of maximal copepod production (CPmax) obtained with gmax were higher in the coastal upwelling zone (<50 km from shore), and correlated significantly to oceanographic variables associated with upwelling conditions. Both CPmax and gmax exhibited negative trends at the fixed station from 2004 to 2006 in association with increased duration of upwelling in the latter year. Annual CPmax ranged between 24 and 52 g C m-2 y-1 with a mean annual P/B ratio of 7.3. We concluded that interannual variation in copepod production resulted from factors and processes regulating copepod abundance and biomass in the absence of bottom-up control, allowing copepods to grow without limitation due to food resources.

  13. Use of the Priestley-Taylor evaporation equation for soil water limited conditions in a small forest clearcut

    USGS Publications Warehouse

    Flint, A.L.; Childs, S.W.

    1991-01-01

    The Priestley-Taylor equation, a simplification of the Penman equation, was used to allow calculations of evapotranspiration under conditions where soil water supply limits evapotranspiration. The Priestley-Taylor coefficient, ??, was calculated to incorporate an exponential decrease in evapotranspiration as soil water content decreases. The method is appropriate for use when detailed meteorological measurements are not available. The data required to determine the parameter for the ?? coefficient are net radiation, soil heat flux, average air temperature, and soil water content. These values can be obtained from measurements or models. The dataset used in this report pertains to a partially vegetated clearcut forest site in southwest Oregon with soil depths ranging from 0.48 to 0.70 m and weathered bedrock below that. Evapotranspiration was estimated using the Bowen ratio method, and the calculated Priestley-Taylor coefficient was fitted to these estimates by nonlinear regression. The calculated Priestley-Taylor coefficient (?????) was found to be approximately 0.9 when the soil was near field capacity (0.225 cm3 cm-3). It was not until soil water content was less than 0.14 cm3 cm-3 that soil water supply limited evapotranspiration. The soil reached a final residual water content near 0.05 cm3 cm-3 at the end of the growing season. ?? 1991.

  14. 12 CFR 575.3 - Mutual holding company reorganizations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 6 2014-01-01 2012-01-01 true Mutual holding company reorganizations. 575.3... COMPANIES § 575.3 Mutual holding company reorganizations. A mutual savings association may reorganize to become a mutual holding company, or join in a mutual holding company reorganization as an...

  15. 12 CFR 239.3 - Mutual holding company reorganizations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 4 2014-01-01 2014-01-01 false Mutual holding company reorganizations. 239.3... RESERVE SYSTEM (CONTINUED) MUTUAL HOLDING COMPANIES (REGULATION MM) Mutual Holding Companies § 239.3 Mutual holding company reorganizations. (a) A mutual savings association may not reorganize to become...

  16. 12 CFR 575.3 - Mutual holding company reorganizations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 6 2013-01-01 2012-01-01 true Mutual holding company reorganizations. 575.3... COMPANIES § 575.3 Mutual holding company reorganizations. A mutual savings association may reorganize to become a mutual holding company, or join in a mutual holding company reorganization as an...

  17. 12 CFR 239.3 - Mutual holding company reorganizations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 4 2013-01-01 2013-01-01 false Mutual holding company reorganizations. 239.3... RESERVE SYSTEM (CONTINUED) MUTUAL HOLDING COMPANIES (REGULATION MM) Mutual Holding Companies § 239.3 Mutual holding company reorganizations. (a) A mutual savings association may not reorganize to become...

  18. 12 CFR 575.3 - Mutual holding company reorganizations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Mutual holding company reorganizations. 575.3... COMPANIES § 575.3 Mutual holding company reorganizations. A mutual savings association may reorganize to become a mutual holding company, or join in a mutual holding company reorganization as an...

  19. 12 CFR 575.3 - Mutual holding company reorganizations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 5 2011-01-01 2011-01-01 false Mutual holding company reorganizations. 575.3... COMPANIES § 575.3 Mutual holding company reorganizations. A mutual savings association may reorganize to become a mutual holding company, or join in a mutual holding company reorganization as an...

  20. 12 CFR 239.3 - Mutual holding company reorganizations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 4 2012-01-01 2012-01-01 false Mutual holding company reorganizations. 239.3... RESERVE SYSTEM (CONTINUED) MUTUAL HOLDING COMPANIES (REGULATION MM) Mutual Holding Companies § 239.3 Mutual holding company reorganizations. (a) A mutual savings association may not reorganize to become...

  1. 12 CFR 575.3 - Mutual holding company reorganizations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 6 2012-01-01 2012-01-01 false Mutual holding company reorganizations. 575.3... COMPANIES § 575.3 Mutual holding company reorganizations. A mutual savings association may reorganize to become a mutual holding company, or join in a mutual holding company reorganization as an...

  2. Onset of fights and mutual assessment in ant founding queens.

    PubMed

    Berthelot, Kévin; Portugal, Felipe Ramon; Jeanson, Raphaël

    2017-03-01

    In animals, the progress and outcome of contests can be influenced by an individual's own condition, their opponent's condition or a combination of the two. The use of chemical information to assess the quality of rivals has been underestimated despite its central role in the regulation of social interactions in many taxa. Here, we studied pairwise contests between founding queens of the ant Lasius niger to investigate whether the decision to engage in agonistic interactions relies on self-assessment or mutual assessment. Queens modulated their aggressive behaviours depending on both their own status and their opponent's status. We found no influence of lipid stores or size on the onset of fights. However, differences in cuticular chemical signatures linked to fertility status accurately predicted the probability of behaving aggressively in pairs. Our study thus suggests that ant queens could rely on mutual assessment via chemical cues to make informed decisions about fight initiation.

  3. Application of thresholds of potential concern and limits of acceptable change in the condition assessment of a significant wetland.

    PubMed

    Rogers, Kerrylee; Saintilan, Neil; Colloff, Matthew J; Wen, Li

    2013-10-01

    We propose a framework in which thresholds of potential concern (TPCs) and limits of acceptable change (LACs) are used in concert in the assessment of wetland condition and vulnerability and apply the framework in a case study. The lower Murrumbidgee River floodplain (the 'Lowbidgee') is one of the most ecologically important wetlands in Australia and the focus of intense management intervention by State and Federal government agencies. We used a targeted management stakeholder workshop to identify key values that contribute to the ecological significance of the Lowbidgee floodplain, and identified LACs that, if crossed, would signify the loss of significance. We then used conceptual models linking the condition of these values (wetland vegetation communities, waterbirds, fish species and the endangered southern bell frog) to measurable threat indicators, for which we defined a management goal and a TPC. We applied this framework to data collected across 70 wetland storages', or eco-hydrological units, at the peak of a prolonged drought (2008) and following extensive re-flooding (2010). At the suggestion of water and wetland mangers, we neither aggregated nor integrated indices but reported separately in a series of chloropleth maps. The resulting assessment clearly identified the effect of rewetting in restoring indicators within TPC in most cases, for most storages. The scale of assessment was useful in informing the targeted and timely management intervention and provided a context for retaining and utilising monitoring information in an adaptive management context.

  4. The activity of nodules of the supernodulating mutant Mtsunn is not limited by photosynthesis under optimal growth conditions.

    PubMed

    Cabeza, Ricardo A; Lingner, Annika; Liese, Rebecca; Sulieman, Saad; Senbayram, Mehmet; Tränkner, Merle; Dittert, Klaus; Schulze, Joachim

    2014-04-10

    Legumes match the nodule number to the N demand of the plant. When a mutation in the regulatory mechanism deprives the plant of that ability, an excessive number of nodules are formed. These mutants show low productivity in the fields, mainly due to the high carbon burden caused through the necessity to supply numerous nodules. The objective of this study was to clarify whether through optimal conditions for growth and CO2 assimilation a higher nodule activity of a supernodulating mutant of Medicago truncatula (M. truncatula) can be induced. Several experimental approaches reveal that under the conditions of our experiments, the nitrogen fixation of the supernodulating mutant, designated as sunn (super numeric nodules), was not limited by photosynthesis. Higher specific nitrogen fixation activity could not be induced through short- or long-term increases in CO2 assimilation around shoots. Furthermore, a whole plant P depletion induced a decline in nitrogen fixation, however this decline did not occur significantly earlier in sunn plants, nor was it more intense compared to the wild-type. However, a distinctly different pattern of nitrogen fixation during the day/night cycles of the experiment indicates that the control of N2 fixing activity of the large number of nodules is an additional problem for the productivity of supernodulating mutants.

  5. The Activity of Nodules of the Supernodulating Mutant Mtsunn Is not Limited by Photosynthesis under Optimal Growth Conditions

    PubMed Central

    Cabeza, Ricardo A.; Lingner, Annika; Liese, Rebecca; Sulieman, Saad; Senbayram, Mehmet; Tränkner, Merle; Dittert, Klaus; Schulze, Joachim

    2014-01-01

    Legumes match the nodule number to the N demand of the plant. When a mutation in the regulatory mechanism deprives the plant of that ability, an excessive number of nodules are formed. These mutants show low productivity in the fields, mainly due to the high carbon burden caused through the necessity to supply numerous nodules. The objective of this study was to clarify whether through optimal conditions for growth and CO2 assimilation a higher nodule activity of a supernodulating mutant of Medicago truncatula (M. truncatula) can be induced. Several experimental approaches reveal that under the conditions of our experiments, the nitrogen fixation of the supernodulating mutant, designated as sunn (super numeric nodules), was not limited by photosynthesis. Higher specific nitrogen fixation activity could not be induced through short- or long-term increases in CO2 assimilation around shoots. Furthermore, a whole plant P depletion induced a decline in nitrogen fixation, however this decline did not occur significantly earlier in sunn plants, nor was it more intense compared to the wild-type. However, a distinctly different pattern of nitrogen fixation during the day/night cycles of the experiment indicates that the control of N2 fixing activity of the large number of nodules is an additional problem for the productivity of supernodulating mutants. PMID:24727372

  6. Alcanivorax borkumensis produces an extracellular siderophore in iron-limitation condition maintaining the hydrocarbon-degradation efficiency.

    PubMed

    Denaro, R; Crisafi, F; Russo, D; Genovese, M; Messina, E; Genovese, L; Carbone, M; Ciavatta, M L; Ferrer, M; Golyshin, P; Yakimov, M M

    2014-10-01

    Obligate marine hydrocarbonoclastic bacteria possess genetic and physiological features to use hydrocarbons as sole source of carbon and to compete for the uptake of nutrients in usually nutrient-depleted marine habitats. In the present work we have studied the siderophore-based iron uptake systems in Alcanivorax borkumensis SK2 and their functioning during biodegradation of an aliphatic hydrocarbon, tetradecane, under iron limitation conditions. The antiSMASH analysis of SK2 genome revealed the presence of two different putative operons of siderophore synthetases. Search for the predicted core structures indicated that one siderophore is clearly affiliated to the family of complex oligopeptidic siderophores possessing an Orn-Ser-Orn carboxyl motif whereas the second one is likely to belong to the family of SA (salicylic acid)-based siderophores. Analyzing the supernatant of SK2 culture, an extracellular siderophore was identified and its structure was resolved. Thus, along with the recently described membrane-associated amphiphilic tetrapeptidic siderophore amphibactin, strain SK2 additionally produces an extracellular type of iron-chelating molecule with structural similarity to pseudomonins. Comparative Q-PCR analysis of siderophore synthetases demonstrated their significant up-regulation in iron-depleted medium. Different expression patterns were recorded for two operons during the early and late exponential phases of growth, suggesting a different function of these two siderophores under iron-depleted conditions.

  7. Investigations of Internal Flow Fields of Constant-Area Mixing-Tubes under Starting-Limit Conditions

    NASA Astrophysics Data System (ADS)

    Kitamura, Eijiro; Tomioka, Sadatake; Sakuranaka, Noboru; Watanabe, Syuichi; Masuya, Goro

    Flow fields in the constant-area mixing tubes of ejector jets were investigated under the starting-limit conditions of an aerodynamic choking mode by performing numerical simulations and cold flow experiments. Pressure recovery was almost completed in the shock-train region. The length of the shock-train region (Lst) was measured under various conditions. Lst was proportional to the mass flow rate ratio of the secondary flow to the primary flow when this ratio was less than 0.15. On the other hand, Lst became almost constant when the mass flow rate ratio exceeded 0.15. Numerical studies showed that this change was caused by the difference in the mechanism of the flow fields. In the cases with low air mass flow rates, the primary and secondary flows almost mixed in a region between the inlets of the mixing tubes and the choking points. The pressure was recovered by a pseudo-shock-wave generated downstream of the choking point. On the other hand, when the mass flow rate ratio was higher than 0.15, the primary and secondary flows were clearly separated at the choking point. The pressure recovery was achieved by the mixing between the primary and secondary flows downstream of the choking point.

  8. On the spatial distribution of the transpiration and soil moisture of a Mediterranean heterogeneous ecosystem in water-limited conditions.

    NASA Astrophysics Data System (ADS)

    Curreli, Matteo; Corona, Roberto; Montaldo, Nicola; Albertson, John D.; Oren, Ram

    2014-05-01

    Mediterranean ecosystems are characterized by a strong heterogeneity, and often by water-limited conditions. In these conditions contrasting plant functional types (PFT, e.g. grass and woody vegetation) compete for the water use. Both the vegetation cover spatial distribution and the soil properties impact the soil moisture (SM) spatial distribution. Indeed, vegetation cover density and type affects evapotranspiration (ET), which is the main lack of the soil water balance in these ecosystems. With the objective to carefully estimate SM and ET spatial distribution in a Mediterranean water-limited ecosystem and understanding SM and ET relationships, an extended field campaign is carried out. The study was performed in a heterogeneous ecosystem in Orroli, Sardinia (Italy). The experimental site is a typical Mediterranean ecosystem where the vegetation is distributed in patches of woody vegetation (wild olives mainly) and grass. Soil depth is low and spatially varies between 10 cm and 40 cm, without any correlation with the vegetation spatial distribution. ET, land-surface fluxes and CO2 fluxes are estimated by an eddy covariance technique based micrometeorological tower. But in heterogeneous ecosystems a key assumption of the eddy covariance theory, the homogeneity of the surface, is not preserved and the ET estimate may be not correct. Hence, we estimate ET of the woody vegetation using the thermal dissipation method (i.e. sap flow technique) for comparing the two methodologies. Due the high heterogeneity of the vegetation and soil properties of the field a total of 54 sap flux sensors were installed. 14 clumps of wild olives within the eddy covariance footprint were identified as the most representative source of flux and they were instrumented with the thermal dissipation probes. Measurements of diameter at the height of sensor installation (height of 0.4 m above ground) were recorded in all the clumps. Bark thickness and sapwood depth were measured on several

  9. Extracting an entanglement signature from only classical mutual information

    NASA Astrophysics Data System (ADS)

    Starling, David J.; Broadbent, Curtis J.; Howell, John C.

    2011-09-01

    We introduce a quantity which is formed using classical notions of mutual information and which is computed using the results of projective measurements. This quantity constitutes a sufficient condition for entanglement and represents the amount of information that can be extracted from a bipartite system for spacelike separated observers. In addition to discussion, we provide simulations as well as experimental results for the singlet and maximally correlated mixed states.

  10. Extracting an entanglement signature from only classical mutual information

    SciTech Connect

    Starling, David J.; Howell, John C.; Broadbent, Curtis J.

    2011-09-15

    We introduce a quantity which is formed using classical notions of mutual information and which is computed using the results of projective measurements. This quantity constitutes a sufficient condition for entanglement and represents the amount of information that can be extracted from a bipartite system for spacelike separated observers. In addition to discussion, we provide simulations as well as experimental results for the singlet and maximally correlated mixed states.

  11. Mutualism between tree shrews and pitcher plants

    PubMed Central

    Moran, Jonathan A; Chin, Lijin

    2010-01-01

    Three species of Nepenthes pitcher plants from Borneo engage in a mutualistic interaction with mountain tree shrews, the basis of which is the exchange of nutritional resources. The plants produce modified “toilet pitchers” that produce copious amounts of exudates, the latter serving as a food source for tree shrews. The exudates are only accessible to the tree shrews when they position their hindquarters over the pitcher orifice. Tree shrews mark valuable resources with feces and regularly defecate into the pitchers when they visit them to feed. Feces represent a valuable source of nitrogen for these Nepenthes species, but there are many facets of the mutualism that are yet to be investigated. These include, but are not limited to, seasonal variation in exudate production rates by the plants, behavioral ecology of visiting tree shrews and the mechanism by which the plants signal to tree shrews that their pitchers represent a food source. Further research into this extraordinary animal-plant interaction is required to gain a better understanding of the benefits to the participating species. PMID:20861680

  12. Calculation of mutual information for nonlinear communication channel at large signal-to-noise ratio

    NASA Astrophysics Data System (ADS)

    Terekhov, I. S.; Reznichenko, A. V.; Turitsyn, S. K.

    2016-10-01

    Using the path-integral technique we examine the mutual information for the communication channel modeled by the nonlinear Schrödinger equation with additive Gaussian noise. The nonlinear Schrödinger equation is one of the fundamental models in nonlinear physics, and it has a broad range of applications, including fiber optical communications—the backbone of the internet. At large signal-to-noise ratio we present the mutual information through the path-integral, which is convenient for the perturbative expansion in nonlinearity. In the limit of small noise and small nonlinearity we derive analytically the first nonzero nonlinear correction to the mutual information for the channel.

  13. Cocoa butter-like lipid production ability of non-oleaginous and oleaginous yeasts under nitrogen-limited culture conditions.

    PubMed

    Wei, Yongjun; Siewers, Verena; Nielsen, Jens

    2017-02-06

    Cocoa butter (CB) extracted from cocoa beans is the main raw material for chocolate production. However, growing chocolate demands and limited CB production has resulted in a shortage of CB supply. CB is mainly composed of three different kinds of triacylglycerols (TAGs), POP (C16:0-C18:1-C16:0), POS (C16:0-C18:1-C18:0), and SOS (C18:0-C18:1-C18:0). The storage lipids of yeasts, mainly TAGs, also contain relative high-level of C16 and C18 fatty acids and might be used as CB-like lipids (CBL). In this study, we cultivated six different yeasts, including one non-oleaginous yeast strain, Saccharomyces cerevisiae CEN.PK113-7D, and five oleaginous yeast strains, Trichosporon oleaginosus DSM11815, Rhodotorula graminis DSM 27356, Lipomyces starkeyi DSM 70296, Rhodosporidium toruloides DSM 70398, and Yarrowia lipolytica CBS 6124, in nitrogen-limited medium and compared their CBL production ability. Under the same growth conditions, we found that TAGs were the main lipids in all six yeasts and that T. oleaginosus can produce more TAGs than the other five yeasts. Less than 3% of the total TAGs were identified as potential SOS in the six yeasts. However, T. oleaginosus produced 27.8% potential POP and POS at levels of 378 mg TAGs/g dry cell weight, hinting that this yeast may have potential as a CBL production host after further metabolic engineering in future.

  14. Limitations of the rheological mucoadhesion method: the effect of the choice of conditions and the rheological synergism parameter.

    PubMed

    Hägerström, Helene; Edsman, Katarina

    2003-04-01

    This work demonstrates several limitations of the simple rheological method that is widely used to investigate mucoadhesion of polymer gels. We establish the importance of the choice of conditions and the synergism parameter for the results obtained in comparative studies. Dynamic rheological measurements were performed on gels based on four slightly different poly(acrylic acid) (Carbopol) polymers and their corresponding mixtures with porcine stomach mucin and bovine submaxillary gland mucin. The rationale for the comparison of the polymers had a large influence on the results obtained. The method does not give the same ranking order when two different comparison strategies are used. Moreover, we show that the results obtained are also sensitive to where in the 'rheological range' the comparison is made, e.g., at which value of G'. Positive values of the synergism parameters are, for example, only seen with weak gels. The choice of synergism parameter also has a bearing on the results obtained, and here we suggest a new refined relative parameter, the log ratio (log(G'(mix)/G'(p))). We also investigated the adhesion of the gel preparations to porcine nasal mucosa, using tensile strength measurements. Increased gel strength resulted in stronger adhesion, which is in contrast to the results from the rheological method, where the positive values of the synergism parameters were seen only with weak gels. On the basis of the limitations demonstrated and discussed, we recommend that the rheological method should not be used as a stand-alone method for the studying of mucoadhesive properties of polymer gels.

  15. Driven diffusive systems with mutually interactive Langmuir kinetics

    NASA Astrophysics Data System (ADS)

    Vuijk, H. D.; Rens, R.; Vahabi, M.; MacKintosh, F. C.; Sharma, A.

    2015-03-01

    We investigate the simple one-dimensional driven model, the totally asymmetric exclusion process, coupled to mutually interactive Langmuir kinetics. This model is motivated by recent studies on clustering of motor proteins on microtubules. In the proposed model, the attachment and detachment rates of a particle are modified depending upon the occupancy of neighboring sites. We first obtain continuum mean-field equations and in certain limiting cases obtain analytic solutions. We show how mutual interactions increase (decrease) the effects of boundaries on the phase behavior of the model. We perform Monte Carlo simulations and demonstrate that our analytical approximations are in good agreement with the numerics over a wide range of model parameters. We present phase diagrams over a selective range of parameters.

  16. Mycorrhiza: A Common Form of Mutualism.

    ERIC Educational Resources Information Center

    Medve, Richard J.

    1978-01-01

    Mycorrhizae are among the most common examples of mutualism. This article discusses their structure, symbolic relationship, factors affecting formation and applying research. Questions are posed and answers suggested. (MA)

  17. Methods for automatized detection of rapid changes in lateral boundary condition fields for NWP limited area models

    NASA Astrophysics Data System (ADS)

    Tudor, M.

    2015-08-01

    Three-hourly temporal resolution of lateral boundary data for limited area models (LAMs) can be too infrequent to resolve rapidly moving storms. This problem is expected to be worse with increasing horizontal resolution. In order to detect intensive disturbances in surface pressure moving rapidly through the model domain, a filtered surface pressure field (MCUF) is computed operationally in the ARPEGE global model of Météo France. The field is distributed in the coupling files along with conventional meteorological fields used for lateral boundary conditions (LBCs) for the operational forecast using limited area model ALADIN (Aire Limitée Adaptation dynamique Développement InterNational) in the Meteorological and Hydrological Service of Croatia (DHMZ). Here an analysis is performed of the MCUF field for the LACE coupling domain for the period from 23 January 2006, when it became available, until 15 November 2014. The MCUF field is a good indicator of rapidly moving pressure disturbances (RMPDs). Its spatial and temporal distribution can be associated with the usual cyclone tracks and areas known to be supporting cyclogenesis. An alternative set of coupling files from the IFS operational run in the European Centre for Medium-Range Weather Forecasts (ECMWF) is also available operationally in DHMZ with 3-hourly temporal resolution, but the MCUF field is not available. Here, several methods are tested that detect RMPDs in surface pressure a posteriori from the IFS model fields provided in the coupling files. MCUF is computed by running ALADIN on the coupling files from IFS. The error function is computed using one-time-step integration of ALADIN on the coupling files without initialization, initialized with digital filter initialization (DFI) or scale-selective DFI (SSDFI). Finally, the amplitude of changes in the mean sea level pressure is computed from the fields in the coupling files. The results are compared to the MCUF field of ARPEGE and the results of same

  18. Static and adaptive feedback control for synchronization of different chaotic oscillators with mutually Lipschitz nonlinearities

    NASA Astrophysics Data System (ADS)

    Muhammad, Riaz; Muhammad, Rehan; Keum-Shik, Hong; Muhammad, Ashraf; Haroon, Ur Rasheed

    2014-11-01

    This paper addresses the control law design for synchronization of two different chaotic oscillators with mutually Lipschitz nonlinearities. For analysis of the properties of two different nonlinearities, an advanced mutually Lipschitz condition is proposed. This mutually Lipschitz condition is more general than the traditional Lipschitz condition. Unlike the latter, it can be used for the design of a feedback controller for synchronization of chaotic oscillators of different dynamics. It is shown that any two different Lipschitz nonlinearities always satisfy the mutually Lipschitz condition. Applying the mutually Lipschitz condition, a quadratic Lyapunov function and uniformly ultimately bounded stability, easily designable and implementable robust control strategies utilizing algebraic Riccati equation and linear matrix inequalities, are derived for synchronization of two distinct chaotic oscillators. Furthermore, a novel adaptive control scheme for mutually Lipschitz chaotic systems is established by addressing the issue of adaptive cancellation of unknown mismatch between the dynamics of different chaotic systems. The proposed control technique is numerically tested for synchronization of two different chaotic Chua's circuits and for obtaining identical behavior between the modified Chua's circuit and the Rössler system.

  19. Complete study of suprathermal oxygen particles in Mars upper thermosphere and exosphere over the range of limiting conditions

    NASA Astrophysics Data System (ADS)

    Valeille, Arnaud; Combi, Michael; Tenishev, Valeriy; Bougher, Stephen; Nagy, Andrew

    As a part of a global effort, the dynamics of the flow of energetic particles through the Martian upper atmosphere has been studied. Being the most important reaction, the dissociative recombination (DR) of O2+ is responsible of most of the production of hot atomic oxygen deep in the thermosphere of Mars. To understand the Martian exosphere, it is then necessary to employ a global kinetic model which can include a self-consistent description of both thermosphere collisional region and exospheric collisionless domain. In this study, we have used our Direct Simulation Monte Carlo (DSMC) model in combination with the 3D Mars Thermosphere General Circulation Model (MTGCM) of Bougher et al. to describe self-consistently the region of the upper thermosphere where the exosphere is generated, the entire exosphere, and its feedback into the thermosphere generally. Along with the effect of ionization, the DSMC method allows us to provide profiles of density and temperature, atmospheric loss rates and return fluxes as functions of the Solar Zenith Angle (SZA) for all cases considered. To present a complete description of this physical problem we examined several of the most limiting cases spanning spatial and temporal domains. Along with solar activity variability, these include comparisons between the polar meridian and the equator at equinox and between the summer and winter polar meridians at perihelion and aphelion conditions, respectively. The contribution of the different physical and chemical escape processes was studied and compared for the present but also earlier Mars epochs characterized by different solar inputs (1 EUV, 3 EUV and 5 EUV) for Equinox conditions. Support for this work comes from NASA Mars Fundamental Research grant NNG05GL80G.

  20. The course of physical functional limitations and occupational conditions in a middle-aged working population in France

    PubMed Central

    2012-01-01

    Background Physical functional limitations (PFL) have mainly been studied in older populations. The aim of this study was to better understand the course of PFL and associations with occupational factors by gender in a middle-aged working population. Methods The data came from 16,950 workers in the ESTEV (Enquête Santé Travail et Vieillissement) cohort in France. PFL were assessed using the physical abilities section of the Nottingham Health Profile. Occupational conditions were measured with a self-administered questionnaire covering physical and psychosocial factors in 1990 and 1995. Multivariate analyses were used to assess the associations. Results The PFL appearance rate in 1995 was the same by gender (6.3%); the rate of PFL recovery was higher in men (23.9% versus 20.9%). Age was an independent factor of PFL at age 47 years or older in both genders after adjusting for confounding factors. The PFL appearance rate in 1995 was higher with physical occupational exposure in 1990, such as awkward work with a dose relation in both genders, while the PFL recovery rate decreased significantly only for men. Exposure to psychosocial occupational conditions, such as having the means to produce quality work in 1990, was significantly associated with a decreased PFL appearance rate in 1995 in both genders, and having high decision latitude in 1990 was associated with a decreased PFL appearance rate in 1995 only in men. Changes in exposure to occupational factors between 1990 and 1995 were associated with the PFL appearance and recovery rates in 1995 in both genders. Conclusions After five years, the course of PFL in this working population changed and was associated with physical and psychosocial occupational factors. Relationships were stronger for the PFL appearance rate in both genders and were weaker for recovery from PFL, mainly among women. PMID:22494385

  1. Rate-limited mass transfer of octane, decane, and dodecane into nonionic surfactants solutions under laminar flow conditions.

    PubMed

    Prak, Dianne J Luning

    2008-05-01

    A key component to predicting the success of utilizing surfactants to enhance the removal of organic liquids from soil system is quantifying micellar solubilization kinetics. In this study, a flow reactor was employed to investigate the influence of surfactant ethoxylate chain length on the rates of solubilization of octane, decane, and dodecane in micellar solutions of a homologous series of purified dodecyl alcohol ethoxylates. Effluent concentration data were fit using a finite element model utilizing a linear-driving-force model to represent mass transfer at the interface. For flow rates between 0.1 and 2 ml min(-1), mass transfer coefficients ranged from 5 x 10(-8) to 7 x 10(-7)m s(-1) and did not vary in a systematic way with either solute structure or surfactant ethoxylate chain length and were lower than those found in pure water. Correlations developed for the Sherwood number based on diffusion coefficients of surfactant micelles containing organic material (organic-laden micelle) exhibit a velocity dependence similar to that found for systems based on aqueous diffusion. These results suggest that under gentle flowing conditions, the mass transfer is limited by diffusion of the organic-laden micelle. Although these trends are specific for this experimental system, the results demonstrate the importance of selecting the proper diffusion coefficient when modeling surfactant solubilization processes.

  2. NAP (davunetide) protects primary hippocampus culture by modulating expression profile of antioxidant genes during limiting oxygen conditions.

    PubMed

    Arya, A; Meena, R; Sethy, N K; Das, M; Sharma, M; Bhargava, K

    2015-04-01

    Hypoxia is a well-known threat to neuronal cells and triggers the pathophysiological syndromes in extreme environments such as high altitudes and traumatic conditions such as stroke. Among several prophylactic molecules proven suitable for ameliorating free radical damage, NAP (an octapeptide with initial amino acids: asparagine/N, alanine/A, and proline/P) can be considered superlative, primarily due to its high permeability into brain through blood-brain barrier and observed activity at femtomolar concentrations. Several mechanisms of action of NAP have been hypothesized for its protective role during hypoxia, yet any distinct mechanism is unknown. Oxidative stress is advocated as the leading event in hypoxia; we, therefore, investigated the regulation of key antioxidant genes to understand the regulatory role of NAP in providing neuroprotection. Primary neuronal culture of rat was subjected to cellular hypoxia by limiting the oxygen concentration to 0.5% for 72 h and observing the prophylactic efficacies of 15fM NAP by conventional cell death assays using flow cytometry. We performed real-time quantitative polymerase chain reaction to comprehend the regulatory mechanism. Further, we validated the significantly regulated candidates by enzyme assays and immunoblotting. In the present study, we report that NAP regulates a major clad of cellular antioxidants and there is an involvement of more than one route of action in neuroprotection during hypoxia.

  3. Activity-Limiting Musculoskeletal Conditions in US Veterans Compared to Non-Veterans: Results from the 2013 National Health Interview Survey

    PubMed Central

    Hinojosa, Ramon

    2016-01-01

    Past military service is associated with health outcomes, both positive and negative. In this study we use the 2013 National Health Interview Survey to examine the constellation of conditions referred to as musculoskeletal disorders (MSDs) for Veterans and non-veterans with health conditions that limit their daily activities. Multivariate logistic regression analysis reveal that Veterans are more likely to report MSDs like neck and back problems, fracture bone and joint problems as an activity limiting problem compared to non-veterans. The relationship between age and reports of activity limiting MSDs is moderated by Veteran status. Veterans in this sample report more activity limiting MSDs at younger ages compared to non-veterans and fewer MSDs at older ages. This research contributes to our understanding of potentially limiting health conditions at earlier ages for Veterans. PMID:28005905

  4. Species-Specific Seed Dispersal in an Obligate Ant-Plant Mutualism

    PubMed Central

    Youngsteadt, Elsa; Baca, Jeniffer Alvarez; Osborne, Jason; Schal, Coby

    2009-01-01

    Throughout lowland Amazonia, arboreal ants collect seeds of specific plants and cultivate them in nutrient-rich nests, forming diverse yet obligate and species-specific symbioses called Neotropical ant-gardens (AGs). The ants depend on their symbiotic plants for nest stability, and the plants depend on AGs for substrate and nutrients. Although the AGs are limited to specific participants, it is unknown at what stage specificity arises, and seed fate pathways in AG epiphytes are undocumented. Here we examine the specificity of the ant-seed interaction by comparing the ant community observed at general food baits to ants attracted to and removing seeds of the AG plant Peperomia macrostachya. We also compare seed removal rates under treatments that excluded vertebrates, arthropods, or both. In the bait study, only three of 70 ant species collected P. macrostachya seeds, and 84% of observed seed removal by ants was attributed to the AG ant Camponotus femoratus. In the exclusion experiment, arthropod exclusion significantly reduced seed removal rates, but vertebrate exclusion did not. We provide the most extensive empirical evidence of species specificity in the AG mutualism and begin to quantify factors that affect seed fate in order to understand conditions that favor its departure from the typical diffuse model of plant-animal mutualism. PMID:19194502

  5. Strain localization in brittle-ductile shear zones: fluid abundant vs fluid limited conditions (an example from Wyangala area, Australia)

    NASA Astrophysics Data System (ADS)

    Spruzeniece, L.; Piazolo, S.

    2015-04-01

    This study focuses on physiochemical processes occurring in a brittle-ductile shear zone at both fluid-present and fluid-limited conditions. In the studied shear zone (Wyangala, SE Australia), a coarse-grained two feldspar-quartz-biotite granite is transformed into a medium grained orthogneiss at the shear zone margins and a fine-grained quartz-muscovite phyllonite in the central parts. The orthogneiss displays cataclasis of feldspar and crystal-plastic deformation of quartz. Quartz accommodates most of the deformation and is extensively recrystallized showing distinct crystallographic preferred orientation (CPO). Feldspar-to-muscovite, biotite-to-muscovite and albitization reactions occur locally at porphyroclasts' fracture surfaces and margins. However, the bulk rock composition shows very little change in respect to the wall rock composition. In contrast, in the shear zone centre quartz occurs as large, weakly deformed porphyroclasts, in sizes similar to that in the wall rock, suggesting that it has undergone little deformation. Feldspars and biotite are almost completely reacted to muscovite, which is arranged in a fine-grained interconnected matrix. Muscovite-rich layers contain significant amounts of fine-grained intermixed quartz with random CPO. These domains are interpreted to have accommodated most of the strain. Bulk rock chemistry data shows a significant increase in SiO2 and depletion in NaO content compared to the wall rock composition. We suggest that the high and low strain fabrics represent markedly different scenarios and cannot be interpreted as a simple sequential development with respect to strain. We suggest that the fabrics and mineralogical changes in the shear zone centre have formed due to fluid influx probably along an initially brittle fracture. Here, hydration reactions dramatically changed the rheological properties of the rock. In the newly produced muscovite-quartz layers creep cavitation associated with grain boundary sliding and

  6. Stochastic mutualism model with Lévy jumps

    NASA Astrophysics Data System (ADS)

    Liu, Qun; Jiang, Daqing; Shi, Ningzhong; Hayat, Tasawar; Alsaedi, Ahmed

    2017-02-01

    In this paper, we consider a stochastic mutualism model with Lévy jumps. First of all, we show that the positive solution of the system is stochastically ultimate bounded. Then under a simple assumption, we establish sufficient and necessary conditions for the stochastic permanence and extinction of the system. The results show an important property of the Lévy jumps: they are unfavorable for the permanence of the species. Moreover, when there are no Lévy jumps, we show that there is a unique ergodic stationary distribution of the corresponding system under certain conditions. Some numerical simulations are introduced to validate the theoretical results.

  7. Microbial fuel cells and osmotic membrane bioreactors have mutual benefits for wastewater treatment and energy production.

    PubMed

    Hou, Dianxun; Lu, Lu; Ren, Zhiyong Jason

    2016-07-01

    This study demonstrates that microbial fuel cells (MFCs) and osmotic membrane bioreactors (OMBRs) can be mutually beneficial when integrated together for wastewater treatment. When connecting MFCs with OMBRs, the solute buildup increased conductivity and buffer capacity, which greatly increased MFC power density from 3 W/m(3) up to 11.5 W/m(3). In turn, the MFCs conditioned and reduced sludge production and therefore reduced forward osmosis (FO) membrane fouling. The MFC-OMBR equipped with new thin-film composite (TFC) membrane showed excellent organic (>95%) and phosphorus removal (>99%) and therefore maintained effluent sCOD below 20 mg/L. However, the nitrogen removal was limited due to the negative surface charge of the thin-film composite membrane and solution chemistry, which led to higher flux of ammonium toward the OMBR draw solution. Further studies are needed to improve nitrogen removal, reduce fouling, and optimize system integration.

  8. Using MEMo to discover mutual exclusivity modules in cancer.

    PubMed

    Ciriello, Giovanni; Cerami, Ethan; Aksoy, Bulent Arman; Sander, Chris; Schultz, Nikolaus

    2013-03-01

    Although individual tumors show surprisingly diverse genomic alterations, these events tend to occur in a limited number of pathways, and alterations that affect the same pathway tend to not co-occur in the same patient. While pathway analysis has been a powerful tool in cancer genomics, our knowledge of oncogenic pathway modules is incomplete. To systematically identify such modules, we have developed a novel method, Mutual Exclusivity Modules in Cancer (MEMo). The method searches and identifies modules characterized by three properties: (1) member genes are recurrently altered across a set of tumor samples; (2) member genes are known to or are likely to participate in the same biological process; and (3) alteration events within the modules are mutually exclusive. MEMo integrates multiple data types and maps genomic alterations to biological pathways. MEMo's mutual exclusivity uses a statistical model that preserves the number of alterations per gene and per sample. The MEMo software, source code and sample data sets are available for download at: http://cbio.mskcc.org/memo.

  9. 30 CFR 203.42 - What conditions and limitations apply to royalty relief for deep wells and phase 1 ultra-deep wells?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... royalty relief for deep wells and phase 1 ultra-deep wells? 203.42 Section 203.42 Mineral Resources BUREAU... Deep Gas Wells on Leases Not Subject to Deep Water Royalty Relief § 203.42 What conditions and limitations apply to royalty relief for deep wells and phase 1 ultra-deep wells? The conditions...

  10. A consumer-resource approach to the density-dependent population dynamics of mutualism

    USGS Publications Warehouse

    Holland, J. Nathaniel; DeAngelis, Donald L.

    2010-01-01

    Like predation and competition, mutualism is now recognized as a consumer resource (C-R) interaction, including, in particular, bi-directional (e.g., coral, plant- mycorrhizae) and uni-directional (e.g., ant-plant defense, plant-pollinator) C-R mutualisms. Here, we develop general theory for the density-dependent population dynamics of mutualism based on the C-R mechanism of interspecific interaction. To test the influence of C-R interactions on the dynamics and stability of bi- and uni-directional C-R mutualisms, we developed simple models that link consumer functional response of one mutualistic species with the resources supplied by another. Phase-plane analyses show that the ecological dynamics of C-R mutualisms are stable in general. Most transient behavior leads to an equilibrium of mutualistic coexistence, at which both species densities are greater than in the absence of interactions. However, due to the basic nature of C-R interactions, certain density-dependent conditions can lead to C-R dynamics characteristic of predator-prey interactions, in which one species overexploits and causes the other to go extinct. Consistent with empirical phenomena, these results suggest that the C-R interaction can provide a broad mechanism for understanding density-dependent population dynamics of mutualism. By unifying predation, competition, and mutualism under the common ecological framework of consumer-resource theory, we may also gain a better understanding of the universal features of interspecific interactions in general.

  11. An orb-weaver spider exploits an ant–acacia mutualism for enemy-free space

    PubMed Central

    Styrsky, John D

    2014-01-01

    Exploiters of protection mutualisms are assumed to represent an important threat for the stability of those mutualisms, but empirical evidence for the commonness or relevance of exploiters is limited. Here, I describe results from a manipulative study showing that an orb-weaver spider, Eustala oblonga, inhabits an ant-acacia for protection from predators. This spider is unique in the orb-weaver family in that it associates closely with both a specific host plant and ants. I tested the protective effect of acacia ants on E. oblonga by comparing spider abundance over time on acacias with ants and on acacias from which entire ant colonies were experimentally removed. Both juvenile and adult spider abundance significantly decreased over time on acacias without ants. Concomitantly, the combined abundance of potential spider predators increased over time on acacias without ants. These results suggest that ant protection of the ant-acacia Acacia melanocerus also protects the spiders, thus supporting the hypothesis that E. oblonga exploits the ant–acacia mutualism for enemy-free space. Although E. oblonga takes advantage of the protection services of ants, it likely exacts little to no cost and should not threaten the stability of the ant–acacia mutualism. Indeed, the potential threat of exploiter species to protection mutualisms in general may be limited to species that exploit the material rewards traded in such mutualisms rather than the protection services. PMID:24558583

  12. Mutual Information Rate and Bounds for It

    PubMed Central

    Baptista, Murilo S.; Rubinger, Rero M.; Viana, Emilson R.; Sartorelli, José C.; Parlitz, Ulrich; Grebogi, Celso

    2012-01-01

    The amount of information exchanged per unit of time between two nodes in a dynamical network or between two data sets is a powerful concept for analysing complex systems. This quantity, known as the mutual information rate (MIR), is calculated from the mutual information, which is rigorously defined only for random systems. Moreover, the definition of mutual information is based on probabilities of significant events. This work offers a simple alternative way to calculate the MIR in dynamical (deterministic) networks or between two time series (not fully deterministic), and to calculate its upper and lower bounds without having to calculate probabilities, but rather in terms of well known and well defined quantities in dynamical systems. As possible applications of our bounds, we study the relationship between synchronisation and the exchange of information in a system of two coupled maps and in experimental networks of coupled oscillators. PMID:23112809

  13. Integrating plant carbon dynamics with mutualism ecology.

    PubMed

    Pringle, Elizabeth G

    2016-04-01

    Plants reward microbial and animal mutualists with carbohydrates to obtain nutrients, defense, pollination, and dispersal. Under a fixed carbon budget, plants must allocate carbon to their mutualists at the expense of allocation to growth, reproduction, or storage. Such carbon trade-offs are indirectly expressed when a plant exhibits reduced growth or fecundity in the presence of its mutualist. Because carbon regulates the costs of all plant mutualisms, carbon dynamics are a common platform for integrating these costs in the face of ecological complexity and context dependence. The ecophysiology of whole-plant carbon allocation could thus elucidate the ecology and evolution of plant mutualisms. If mutualisms are costly to plants, then they must be important but frequently underestimated sinks in the terrestrial carbon cycle.

  14. Mutual information and spontaneous symmetry breaking

    NASA Astrophysics Data System (ADS)

    Hamma, A.; Giampaolo, S. M.; Illuminati, F.

    2016-01-01

    We show that the metastable, symmetry-breaking ground states of quantum many-body Hamiltonians have vanishing quantum mutual information between macroscopically separated regions and are thus the most classical ones among all possible quantum ground states. This statement is obvious only when the symmetry-breaking ground states are simple product states, e.g., at the factorization point. On the other hand, symmetry-breaking states are in general entangled along the entire ordered phase, and to show that they actually feature the least macroscopic correlations compared to their symmetric superpositions is highly nontrivial. We prove this result in general, by considering the quantum mutual information based on the two-Rényi entanglement entropy and using a locality result stemming from quasiadiabatic continuation. Moreover, in the paradigmatic case of the exactly solvable one-dimensional quantum X Y model, we further verify the general result by considering also the quantum mutual information based on the von Neumann entanglement entropy.

  15. 78 FR 67320 - Special Conditions: Airbus, Model A350-900 series Airplane; Pitch and Roll Limiting by Electronic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-12

    ... feature(s) associated with the Electronic Flight Control System that limits pitch and roll attitude... order to substantiate the pitch and roll attitude limiting functions and the appropriateness of the... attitudes greater than +30 degrees and less than -15 degrees, and roll angles greater than plus or minus...

  16. 7 CFR 301.76-7 - Additional conditions for issuance of certificates and limited permits for regulated articles...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... limited permits for regulated articles moved interstate from areas quarantined for citrus greening. 301.76... permits for regulated articles moved interstate from areas quarantined for citrus greening. (a) Additional... limited permit attached to the consignee's copy of the waybill. (5) The nursery stock is moved...

  17. 7 CFR 301.76-6 - Additional conditions for issuance of certificates and limited permits for regulated articles...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... limited permits for regulated articles moved interstate from areas quarantined for Asian citrus psyllid... certificates and limited permits for regulated articles moved interstate from areas quarantined for Asian... be moved interstate is clearly labeled with the certificate. (4) A copy of the certificate will...

  18. 7 CFR 301.76-6 - Additional conditions for issuance of certificates and limited permits for regulated articles...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... limited permits for regulated articles moved interstate from areas quarantined for Asian citrus psyllid... certificates and limited permits for regulated articles moved interstate from areas quarantined for Asian... be moved interstate is clearly labeled with the certificate. (4) A copy of the certificate will...

  19. 7 CFR 301.76-6 - Additional conditions for issuance of certificates and limited permits for regulated articles...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... limited permits for regulated articles moved interstate from areas quarantined for Asian citrus psyllid... certificates and limited permits for regulated articles moved interstate from areas quarantined for Asian... been sealed with an agricultural seal placed by an inspector. (3) The container that will be...

  20. 7 CFR 301.76-6 - Additional conditions for issuance of certificates and limited permits for regulated articles...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... limited permits for regulated articles moved interstate from areas quarantined only for Asian citrus... issuance of certificates and limited permits for regulated articles moved interstate from areas quarantined... be moved interstate is clearly labeled with the certificate. (4) A copy of the certificate will...

  1. Conceptual Alignment: How Brains Achieve Mutual Understanding.

    PubMed

    Stolk, Arjen; Verhagen, Lennart; Toni, Ivan

    2016-03-01

    We share our thoughts with other minds, but we do not understand how. Having a common language certainly helps, but infants' and tourists' communicative success clearly illustrates that sharing thoughts does not require signals with a pre-assigned meaning. In fact, human communicators jointly build a fleeting conceptual space in which signals are a means to seek and provide evidence for mutual understanding. Recent work has started to capture the neural mechanisms supporting those fleeting conceptual alignments. The evidence suggests that communicators and addressees achieve mutual understanding by using the same computational procedures, implemented in the same neuronal substrate, and operating over temporal scales independent from the signals' occurrences.

  2. Wideband Direction of Arrival Estimation in the Presence of Unknown Mutual Coupling.

    PubMed

    Li, Weixing; Zhang, Yue; Lin, Jianzhi; Guo, Rui; Chen, Zengping

    2017-02-06

    This paper investigates a subarray based algorithm for direction of arrival (DOA) estimation of wideband uniform linear array (ULA), under the presence of frequency-dependent mutual coupling effects. Based on the Toeplitz structure of mutual coupling matrices, the whole array is divided into the middle subarray and the auxiliary subarray. Then two-sided correlation transformation is applied to the correlation matrix of the middle subarray instead of the whole array. In this way, the mutual coupling effects can be eliminated. Finally, the multiple signal classification (MUSIC) method is utilized to derive the DOAs. For the condition when the blind angles exist, we refine DOA estimation by using a simple approach based on the frequency-dependent mutual coupling matrixes (MCMs). The proposed method can achieve high estimation accuracy without any calibration sources. It has a low computational complexity because iterative processing is not required. Simulation results validate the effectiveness and feasibility of the proposed algorithm.

  3. Wideband Direction of Arrival Estimation in the Presence of Unknown Mutual Coupling

    PubMed Central

    Li, Weixing; Zhang, Yue; Lin, Jianzhi; Guo, Rui; Chen, Zengping

    2017-01-01

    This paper investigates a subarray based algorithm for direction of arrival (DOA) estimation of wideband uniform linear array (ULA), under the presence of frequency-dependent mutual coupling effects. Based on the Toeplitz structure of mutual coupling matrices, the whole array is divided into the middle subarray and the auxiliary subarray. Then two-sided correlation transformation is applied to the correlation matrix of the middle subarray instead of the whole array. In this way, the mutual coupling effects can be eliminated. Finally, the multiple signal classification (MUSIC) method is utilized to derive the DOAs. For the condition when the blind angles exist, we refine DOA estimation by using a simple approach based on the frequency-dependent mutual coupling matrixes (MCMs). The proposed method can achieve high estimation accuracy without any calibration sources. It has a low computational complexity because iterative processing is not required. Simulation results validate the effectiveness and feasibility of the proposed algorithm. PMID:28178177

  4. Mutual Group Hypnosis: A Social Interaction Analysis.

    ERIC Educational Resources Information Center

    Sanders, Shirley

    Mutual Group Hypnosis is discussed in terms of its similarity to group dynamics in general and in terms of its similarity to a social interaction program (Role Modeling) designed to foster the expression of warmth and acceptance among group members. Hypnosis also fosters a regression to prelogical thought processes in the service of the ego. Group…

  5. Mutually unbiased bases and generalized Bell states

    SciTech Connect

    Klimov, Andrei B.; Sych, Denis; Sanchez-Soto, Luis L.; Leuchs, Gerd

    2009-05-15

    We employ a straightforward relation between mutually unbiased and Bell bases to extend the latter in terms of a direct construction for the former. We analyze in detail the properties of these generalized Bell states, showing that they constitute an appropriate tool for testing entanglement in bipartite multiqudit systems.

  6. Do Mutual Children Cement Bonds in Stepfamilies?

    ERIC Educational Resources Information Center

    Ganong, Lawrence H.; Coleman, Marilyn

    1988-01-01

    Interviewed 105 midwestern stepfamilies, 39 of whom had reproduced together. Found no significant differences between families with mutual children and those without in terms of marital adjustment, stepparent- and parent-child relationships, and stepfamily affect. It was not possible to predict which families were most likely to reproduce together…

  7. Mutual diffusion of interacting membrane proteins.

    PubMed Central

    Abney, J R; Scalettar, B A; Owicki, J C

    1989-01-01

    The generalized Stokes-Einstein equation is used, together with the two-dimensional pressure equation, to analyze mutual diffusion in concentrated membrane systems. These equations can be used to investigate the role that both direct and hydrodynamic interactions play in determining diffusive behavior. Here only direct interactions are explicitly incorporated into the theory at high densities; however, both direct and hydrodynamic interactions are analyzed for some dilute solutions. We look at diffusion in the presence of weak attractions, soft repulsions, and hard-core repulsions. It is found that, at low densities, attractions retard mutual diffusion while repulsions enhance it. Mechanistically, attractions tend to tether particles together and oppose the dissipation of gradients or fluctuations in concentration, while repulsions provide a driving force that pushes particles apart. At higher concentrations, changes in the structure of the fluid enhance mutual diffusion even in the presence of attractions. It is shown that the theoretical description of postelectrophoresis relaxation and fluorescence correlation spectroscopy experiments must be modified if interacting systems are studied. The effects of interactions on mutual diffusion coefficients have probably already been seen in postelectrophoresis relaxation experiments. PMID:2775829

  8. Thirty Years of Natural Satellites Mutual Events Observations

    NASA Astrophysics Data System (ADS)

    Arlot, Jean-eudes; Events Observers, Mutual

    2009-09-01

    Phenomena in the Solar System have been observed for years: solar and lunar eclipses, occultations of stars by the Moon and the asteroids, eclipses of the satellites of Jupiter. Since 1973, mutual occultations and eclipses of the satellites of Jupiter, Saturn and Uranus were observed extensively during each opportunity i.e. the equinox on the planet: why? The study of the systems of natural satellites needs to explore the dynamics of these objects: each small dynamical effect is the signature of some physical property. In order to validate the theoretical models, very accurate observations are needed. Most of the direct astrometric observations have their accuracy limited by the diffraction of the light in the telescope and by the star catalogues used for calibration. Phenomena have not this limitation: the accuracy is not in angle but in kilometres in space. Since, the observed satellites have no atmosphere, these photometric events are easy to analyse providing relative positions accurate to a few kilometres corresponding to a few mas in geocentric angle. More, during an occultation, the surface of the satellites may be studied: volcanoes of Io (positions and fluxes) were observed that way. Mutual events observations together with the best observations made since several decades allowed improving dynamical models of the satellites systems of Jupiter, Saturn and Uranus. Concerning Io, the dissipation of energy in its internal structure by the Jovian tides has been made into evidence thanks to fitting the models on accurate observations including mutual events. Eight observational campaigns were organized for the Jovian satellites, three for the Saturnians and one for the Uranians providing more than 1400 light curves (see the data base at http://www.imcce.fr/fr/ephemerides/generateur/saimirror/obsindhe.htm ). The author acknowledges the numerous observers worldwide who provide the observations, the observatories permitting observations and the French CNRS who

  9. Paul Drude's Prediction of Nonreciprocal Mutual Inductance for Tesla Transformers

    PubMed Central

    McGuyer, Bart

    2014-01-01

    Inductors, transmission lines, and Tesla transformers have been modeled with lumped-element equivalent circuits for over a century. In a well-known paper from 1904, Paul Drude predicts that the mutual inductance for an unloaded Tesla transformer should be nonreciprocal. This historical curiosity is mostly forgotten today, perhaps because it appears incorrect. However, Drude's prediction is shown to be correct for the conditions treated, demonstrating the importance of constraints in deriving equivalent circuits for distributed systems. The predicted nonreciprocity is not fundamental, but instead is an artifact of the misrepresentation of energy by an equivalent circuit. The application to modern equivalent circuits is discussed. PMID:25542040

  10. Limited sampling strategies to estimate exposure to the green tea polyphenol, epigallocatechin gallate, in fasting and fed conditions.

    PubMed

    Foster, David R; Sowinski, Kevin M; Chow, H H Sherry; Overholser, Brian R

    2007-12-01

    The objective of this study was to develop an efficient sampling strategy to predict epigallocatechin gallate (EGCG) pharmacokinetics after green tea administration. Ten healthy subjects received a single 800-mg oral dose of EGCG administered as Polyphenon E under both fasting and fed conditions. Plasma samples were serially collected over 24 hours and EGCG concentrations were determined. A one-compartment model with a lag time for absorption best fit the concentration-time data. Maximum A Posteriori Bayesian (MAPB) priors were developed by simultaneously fitting pharmacokinetic parameters from both study phases. The D-optimal sampling designs were determined and Monte Carlo simulations were performed. The original model with the estimators was used to fit the simulated data with the optimized sampling schemes. Two and three optimal sampling strategies (OSS-2 and OSS-3, respectively) were developed. The median two sampling times for OSS-2 were 1.3 and 6.9 hours (fasting conditions) and 3.4 and 8.7 hours (fed conditions). The median three sampling times for OSS-3 were 0.7, 1.4, and 7.0 hours (fasting conditions) and 1.4, 3.6, and 8.7 hours (fed conditions). The predictive power of OSS-3 was greater than that of OSS-2, under both fasted and fed conditions, and both strategies had greater predictive performance under fasting conditions. The sampling schemes were accurate and precise in predicting EGCG oral clearance (or area under the curve with known doses), and hence exposure, under both fasting and fed conditions. The increased predictive performance for estimating pharmacokinetic parameters under fasting conditions appeared to be the result of a decreased variability in absorption.

  11. Mutual Coupling Compensation on Spectral-based DOA Algorithm

    NASA Astrophysics Data System (ADS)

    Sanudin, R.

    2016-11-01

    Direction of arrival (DOA) estimation using isotropic antenna arrays are commonly being implemented without considering the mutual coupling effect in between the array elements. This paper presents an analysis of DOA estimation with mutual coupling compensation using a linear antenna array. Mutual coupling effect is represented by mutual coupling coefficients and taken into account when calculating the array output. The mutual coupling compensation technique exploits a banded mutual coupling matrix to reduce the computational complexity. The banded matrix reflects the relationship between mutual coupling effect and the element spacing in an antenna array. The analysis is being carried out using the Capon algorithm, one of spectral-based DOA algorithms, for estimating the DOA of incoming signals. Computer simulations are performed to show the performance of the mutual coupling compensation technique on DOA estimation. Simulation results show that, in term of estimation resolution, the mutual coupling compensation technique manages to obtain a comparable results compared to the case without mutual coupling consideration. However, the mutual coupling compensation technique produces significant estimation error compared to the case without mutual coupling. The study concludes that the banded matrix of mutual coupling coefficients should be properly designed to improve the performance of mutual coupling compensation technique in DOA estimation.

  12. The Sky is the Limit: Free Boundary Conditions in AdS3 Chern-Simons Theory

    NASA Astrophysics Data System (ADS)

    Apolo, Luis; Sundborg, Bo

    We test the effects of new diffeomorphism invariant boundary terms in SL(2,R)×SL(2,R) Chern-Simons theory. The gravitational interpretation corresponds to free AdS3 boundary conditions, without restrictions on the boundary geometry. The boundary theory is the theory of a string in a target AdS3. Its Virasoro conditions can eliminate ghosts. Generalisations to SL(N,R)×SL(N,R) higher spin theories and many other questions are still unexplored.

  13. Using Multiple Approaches, including δ18O Signatures of Phosphate to Investigate Potential Phosphorus Limitation and Cycling under Changing Climate Conditions

    NASA Astrophysics Data System (ADS)

    Roberts, K.; Paytan, A.; Field, C. B.; Honn, E.; Edwards, E.; Gottlieb, R.

    2012-12-01

    Phosphorus (P) is often a limiting or co-limiting nutrient in terrestrial systems. It has been proposed that it will play an even greater role in ecosystems experiencing some of the many predicted effects of climate change, in particular release from nitrogen limitation. Recent work in 2007 by Menge et al. suggests that this is indeed a possibility. To investigate the potential for P limitation, and P cycling under multiple controlled conditions we collected samples from the Jasper Ridge Global Change Experiment (JRGCE) in May 2011. For over a decade the JRGCE has been manipulating four key parameters predicted to change in the future in a native Californian grassland system. Elevated Nitrogen deposition, increased precipitation, increased pCO2, and increased temperature are applied and monitored in a split plot design at the Jasper Ridge Biological Preserve in the eastern foothills of the Santa Cruz Mountains, California. Work done previously at the site using a suite of indicators of the potential P limitation suggest P limitation in some of the manipulated plots in the JRGCE. In this study we replicate a subset of the prior analyses to compare inter-annual signals of P limitation, and further attempt to utilize the oxygen isotopes of phosphate to investigate P cycling in soils at JRGCE. A fractional soil extraction process for phosphate enables separation of several operationally defined P pools, and provides auxiliary information regarding the relative concentrations of bio-available P, and relevant minerals in this grassland system under the varied conditions.

  14. Assessment of the limits to peak power of 1100nm broad area single emitter diode lasers under short pulse conditions

    NASA Astrophysics Data System (ADS)

    Wang, X.; Crump, P.; Pietrzak, A.; Schultz, C.; Klehr, A.; Hoffmann, T.; Liero, A.; Ginolas, A.; Einfeldt, S.; Bugge, F.; Erbert, G.; Tränkle, G.

    2009-02-01

    High power diode lasers are the root source of optical energy in all high performance laser systems. As their performance advances, diode lasers are increasingly taking the place of other sources. Short pulse, sub-microsecond-class, high power lasers are important for many applications but historically, diode lasers have not been able to reach high enough peak pulse powers with adequate reliability, limited by physical effects such as facet failure. By combining robust facet passivation with thick super large optical cavity waveguides, greatly increased optical output power can be achieved. We present here the results of a study using commercial high current short pulse sources (>200A, <500ns) to assess the performance and endurance limits of high power broad area devices. We find that our lasers can be driven with a peak power density of over 110MWcm-2 without failure for more than 3×107 pulses. For example, on testing to 240A, single emitter 200μm stripe 1100nm broad area devices reach 124W (46μJ) without failure, and 60μm stripes reach 88W. In practice, high injection effects such as carrier accumulation in waveguide typically limit peak power. We review these remaining limitations, and discuss how they can be overcome.

  15. Strategies for maintaining fruit quality in northern highbush blueberry under water limited conditions: Deficit irrigation and reduced crop loads

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many commercial blueberry (Vaccinium sp.) fields are irrigated, but mandatory water restrictions may soon limit the availability of irrigation water in several important blueberry growing regions such as California and eastern Washington. New strategies are needed to maintain fruit quality with less...

  16. 7 CFR 301.76-7 - Additional conditions for issuance of certificates and limited permits for regulated articles...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... limited permits for regulated articles moved interstate from areas quarantined for citrus greening. 301.76... permits for regulated articles moved interstate from areas quarantined for citrus greening. (a) Additional... moved interstate in that container. (4) A copy of the certificate is attached to the consignee's copy...

  17. 7 CFR 301.76-7 - Additional conditions for issuance of certificates and limited permits for regulated articles...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... limited permits for regulated articles moved interstate from areas quarantined for citrus greening. 301.76... permits for regulated articles moved interstate from areas quarantined for citrus greening. (a) Additional... moved interstate in that container. (4) A copy of the certificate is attached to the consignee's copy...

  18. 7 CFR 301.76-7 - Additional conditions for issuance of certificates and limited permits for regulated articles...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... limited permits for regulated articles moved interstate from areas quarantined for citrus greening. 301.76... permits for regulated articles moved interstate from areas quarantined for citrus greening. (a) Additional... moved interstate in that container. (4) A copy of the certificate is attached to the consignee's copy...

  19. 78 FR 11554 - Special Conditions: Embraer S.A., Model EMB-550 Airplane, Limit Pilot Forces for Sidestick Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-19

    ... to be operated with only one hand. The applicable airworthiness regulations do not contain adequate... is designed to be operated using only one hand. The requirement of 14 CFR 25.397(c), which defines... to be operated using only one hand. The requirement of 14 CFR 25.397(c), which defines limit...

  20. No evidence of carbon limitation with tree age and height in Nothofagus pumilio under Mediterranean and temperate climate conditions

    PubMed Central

    Piper, Frida I.; Fajardo, Alex

    2011-01-01

    Background and Aims Trees universally decrease their growth with age. Most explanations for this trend so far support the hypothesis that carbon (C) gain becomes limited with age; though very few studies have directly assessed the relative reductions of C gain and C demand with tree age. It has also been suggested that drought enhances the effect of C gain limitation in trees. Here tests were carried out to determine whether C gain limitation is causing the growth decay with tree age, and whether drought accentuates its effect. Methods The balance between C gain and C demand across tree age and height ranges was estimated. For this, the concentration of non-structural carbohydrates (NSCs) in stems and roots of trees of different ages and heights was measured in the deciduous temperate species Nothofagus pumilio. An ontogenetic decrease in NSCs indicates support for C limitation. Furthermore, the importance of drought in altering the C balance with ontogeny was assessed by sampling the same species in Mediterranean and humid climate locations in the southern Andes of Chile. Wood density (WD) and stable carbon isotope ratios (δ13C) were also determined to examine drought constraints on C gain. Key Results At both locations, it was effectively found that tree growth ultimately decreased with tree age and height. It was found, however, that NSC concentrations did not decrease with tree age or height when WD was considered, suggesting that C limitation is not the ultimate mechanism causing the age/height-related declining tree growth. δ13C decreased with tree age/height at the Mediterranean site only; drought effect increased with tree age/height, but this pattern was not mirrored by the levels of NSCs. Conclusions The results indicate that concentrations of C storage in N. pumilio trees do not decrease with tree age or height, and that reduced C assimilation due to summer drought does not alter this pattern. PMID:21852277

  1. 30 CFR 203.42 - What conditions and limitations apply to royalty relief for deep wells and phase 1 ultra-deep wells?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What conditions and limitations apply to royalty relief for deep wells and phase 1 ultra-deep wells? 203.42 Section 203.42 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR MINERALS REVENUE MANAGEMENT RELIEF OR REDUCTION...

  2. The Importance of Awareness and Communication for the Inclusion of Young People with Life-Limiting and Life-Threatening Conditions in Mainstream Schools and Colleges

    ERIC Educational Resources Information Center

    Asprey, Anthea; Nash, Tricia

    2006-01-01

    Anthea Asprey and Tricia Nash both belong to the Children's Hospice South West Research Group, based at the University of Exeter. In this article, they report one aspect of a research project designed to determine the adequacy of support for young people with life-limiting and life-threatening conditions in the education system. They describe here…

  3. 20 CFR 662.420 - Under what limited conditions may the Local Board be designated or certified as the One-Stop...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Board be designated or certified as the One-Stop operator? 662.420 Section 662.420 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR DESCRIPTION OF THE ONE-STOP SYSTEM UNDER TITLE I OF THE WORKFORCE INVESTMENT ACT One-Stop Operators § 662.420 Under what limited conditions may...

  4. Approaches to managing uncertainty in people with life-limiting conditions: role of communication and palliative care.

    PubMed

    Etkind, S N; Koffman, J

    2016-07-01

    Patients with any major illness can expect to experience uncertainty about the nature of their illness, its treatment and their prognosis. Prognostic uncertainty is a particular source of patient distress among those living with life-limiting disease. Uncertainty also affects professionals and it has been argued that the level of professional tolerance of uncertainty can affect levels of investigation as well as healthcare resource use. We know that the way in which uncertainty is recognised, managed and communicated can have important impacts on patients' treatment and quality of life. Current approaches to uncertainty in life-limiting illness include the use of care bundles and approaches that focus on communication and education. The experience in communicating in difficult situations that specialist palliative care professionals can provide may also be of benefit for patients with life-limiting illness in the context of uncertainty. While there are a number of promising approaches to uncertainty, as yet few interventions targeted at recognising and addressing uncertainty have been fully evaluated and further research is needed in this area.

  5. 77 FR 69571 - Special Conditions: Embraer S.A., Model EMB-550 Airplane, Limit Pilot Forces for Sidestick Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-20

    ... features: The Embraer S.A. Model EMB-550 airplane is equipped with a sidestick controller instead of a... The Embraer S.A. Model EMB-550 airplane is equipped with a sidestick controller instead of a... Federal Aviation Administration 14 CFR Part 25 Special Conditions: Embraer S.A., Model EMB-550...

  6. Direct and interactive effects of light and nutrients on the legume-rhizobia mutualism

    NASA Astrophysics Data System (ADS)

    Lau, Jennifer A.; Bowling, Evan James; Gentry, Lowell E.; Glasser, Paul A.; Monarch, Elizabeth A.; Olesen, Whitney M.; Waxmonsky, Jillian; Young, Ryan Thomas

    2012-02-01

    The relative abundance of traded resources can alter the outcomes of symbioses, potentially shifting mutually-beneficial interactions into interactions that are detrimental to one or both partners. We manipulated the legume-rhizobia symbiosis and light and nutrient levels to investigate how the net growth benefits to both partners shift across environments differing in the availability of both traded resources. In low nutrient, high light environments, rhizobia increased mean plant biomass by 62%. In contrast, when plants were light-limited, rhizobia did not increase above-ground biomass and reduced mean below-ground biomass by 46%. Similarly, rhizobia only increased plant biomass under low nutrient conditions. Resource availability also affected nodule traits correlated with rhizobia fitness, with light-limited plants producing fewer and smaller nodules. Our results suggest that the growth benefits to both partners in the legume-rhizobia symbiosis depend on the availability of both traded resources. We also detected evidence, however, that plants may reduce investment in symbionts as the net benefits of association decrease, potentially limiting how far this interaction shifts toward parasitism in low-light, high nutrient environments.

  7. Hardware device binding and mutual authentication

    DOEpatents

    Hamlet, Jason R; Pierson, Lyndon G

    2014-03-04

    Detection and deterrence of device tampering and subversion by substitution may be achieved by including a cryptographic unit within a computing device for binding multiple hardware devices and mutually authenticating the devices. The cryptographic unit includes a physically unclonable function ("PUF") circuit disposed in or on the hardware device, which generates a binding PUF value. The cryptographic unit uses the binding PUF value during an enrollment phase and subsequent authentication phases. During a subsequent authentication phase, the cryptographic unit uses the binding PUF values of the multiple hardware devices to generate a challenge to send to the other device, and to verify a challenge received from the other device to mutually authenticate the hardware devices.

  8. Mutual synchronization of weakly coupled gyrotrons

    SciTech Connect

    Rozental, R. M.; Glyavin, M. Yu.; Sergeev, A. S.; Zotova, I. V.; Ginzburg, N. S.

    2015-09-15

    The processes of synchronization of two weakly coupled gyrotrons are studied within the framework of non-stationary equations with non-fixed longitudinal field structure. With the allowance for a small difference of the free oscillation frequencies of the gyrotrons, we found a certain range of parameters where mutual synchronization is possible while a high electronic efficiency is remained. It is also shown that synchronization regimes can be realized even under random fluctuations of the parameters of the electron beams.

  9. Three-Ship Mutual Interference Tests

    DTIC Science & Technology

    1965-11-16

    increase beyond this event; the data before Event 500 do not show these effects. Short duration transmit-receive misalignment as observed aboard GARCIA , is...on BELKNAP and GARCIA have not been noted on McCLOY. ii 10 CONFIDENTIAL CONFIDENTIAL TRACOR, jNC - , S, Aig? Te~oS 3. CORRECTED SEA TEST LOG Complete...frequency band causing mutual influence. In this example, chart #1 shows BELKNAP and GARCIA influencing McCLOY at a higher frequency band. Sanborn

  10. Combating isolation: Building mutual mentoring networks

    NASA Astrophysics Data System (ADS)

    Cox, Anne J.

    2015-12-01

    Women physicists can often feel isolated at work. Support from a grant through the ADVANCE program of the National Science Foundation (U.S. government funding) created mutual mentoring networks aimed at combating isolation specifically for women faculty at undergraduate-only institutions. This paper will discuss the organization of one such network, what contributed to its success, some of the outcomes, and how it might be implemented in other contexts.

  11. Centrosome misorientation mediates slowing of the cell cycle under limited nutrient conditions in Drosophila male germline stem cells.

    PubMed

    Roth, Therese M; Chiang, C-Y Ason; Inaba, Mayu; Yuan, Hebao; Salzmann, Viktoria; Roth, Caitlin E; Yamashita, Yukiko M

    2012-04-01

    Drosophila male germline stem cells (GSCs) divide asymmetrically, balancing self-renewal and differentiation. Although asymmetric stem cell division balances between self-renewal and differentiation, it does not dictate how frequently differentiating cells must be produced. In male GSCs, asymmetric GSC division is achieved by stereotyped positioning of the centrosome with respect to the stem cell niche. Recently we showed that the centrosome orientation checkpoint monitors the correct centrosome orientation to ensure an asymmetric outcome of the GSC division. When GSC centrosomes are not correctly oriented with respect to the niche, GSC cell cycle is arrested/delayed until the correct centrosome orientation is reacquired. Here we show that induction of centrosome misorientation upon culture in poor nutrient conditions mediates slowing of GSC cell proliferation via activation of the centrosome orientation checkpoint. Consistently, inactivation of the centrosome orientation checkpoint leads to lack of cell cycle slowdown even under poor nutrient conditions. We propose that centrosome misorientation serves as a mediator that transduces nutrient information into stem cell proliferation, providing a previously unappreciated mechanism of stem cell regulation in response to nutrient conditions.

  12. Dwarf and tiller-enhancing 1 regulates growth and development by influencing boron uptake in boron limited conditions in rice.

    PubMed

    Liu, Kai; Liu, Ling-Long; Ren, Yu-Long; Wang, Zhi-Quan; Zhou, Kun-Neng; Liu, Xi; Wang, Dan; Zheng, Ming; Cheng, Zhi-Jun; Lin, Qi-Bing; Wang, Jiu-Lin; Wu, Fu-Qing; Zhang, Xin; Guo, Xiu-Ping; Wang, Chun-Ming; Zhai, Hu-Qu; Jiang, Ling; Wan, Jian-Min

    2015-07-01

    Boron (B) is essential for plant growth, and B deficiency causes severe losses in crop yield. Here we isolated and characterized a rice (Oryza sativa L.) mutant named dwarf and tiller-enhancing 1 (dte1), which exhibits defects under low-B conditions, including retarded growth, increased number of tillers and impaired pollen fertility. Map-based cloning revealed that dte1 encodes a NOD26-LIKE INTRINSIC PROTEIN orthologous to known B channel proteins AtNIP5;1 in Arabidopsis and TASSEL-LESS1 in maize. Its identity was verified by transgenic complementation and RNA-interference. Subcellular localization showed DTE1 is mainly localized in the plasma membrane. The accumulation of DTE1 transcripts both in roots and shoots significantly increased within 3h of the onset of B starvation, but decreased within 1h of B replenishment. GUS staining indicated that DTE1s are expressed abundantly in exodermal cells in roots, as well as in nodal region of adult leaves. Although the dte1 mutation apparently reduces the total B content in plants, it does not affect in vivo B concentrations under B-deficient conditions. These data provide evidence that DTE1 is critical for vegetative growth and reproductive development in rice grown under B-deficient conditions.

  13. 47 CFR 90.165 - Procedures for mutually exclusive applications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Applications and Authorizations Special Rules Governing Facilities Used to Provide Commercial Mobile Radio Services § 90.165 Procedures for mutually exclusive applications. Mutually exclusive commercial mobile radio service applications are processed...

  14. Sequence comparisons via algorithmic mutual information

    SciTech Connect

    Milosavijevic, A.

    1994-12-31

    One of the main problems in DNA and protein sequence comparisons is to decide whether observed similarity of two sequences should be explained by their relatedness or by mere presence of some shared internal structure, e.g., shared internal tandem repeats. The standard methods that are based on statistics or classical information theory can be used to discover either internal structure or mutual sequence similarity, but cannot take into account both. Consequently, currently used methods for sequence comparison employ {open_quotes}masking{close_quotes} techniques that simply eliminate sequences that exhibit internal repetitive structure prior to sequence comparisons. The {open_quotes}masking{close_quotes} approach precludes discovery of homologous sequences of moderate or low complexity, which abound at both DNA and protein levels. As a solution to this problem, we propose a general method that is based on algorithmic information theory and minimal length encoding. We show that algorithmic mutual information factors out the sequence similarity that is due to shared internal structure and thus enables discovery of truly related sequences. We extend the recently developed algorithmic significance method to show that significance depends exponentially on algorithmic mutual information.

  15. Observations of Pluto-Charon mutual events

    SciTech Connect

    Blanco, C.; Di Martino, M.; Ferreri, W.; Osservatorio Astronomico, Turin )

    1989-07-01

    As part of the planned 'Pluto-Charon Mutual Eclipse Season Campaign', one mutual event was observed at the ESO Observatory on July 10, 1986 and seven mutual events were observed at the Serra La Nave stellar station of Catania Astrophysical Observatory from April 29 to July 21, 1987. At ESO the measurements were performed at the 61-cm Bochum telescope equipped with a photon-counting system and U, B, V, filters; at Serra La Nave the Cassegrain focus of the 91-cm reflector was equipped with a photon-counting system and B and V filters. The observed light losses and contact times do not show relevant systematic deviations from the predicted ones. An examination of the behavior of the B and V light curves gives slight indications of a different slope of the B and V light loss of the same event for a superior or an inferior event, and shows that the superior events are shallower at wavelengths longer than B. 6 refs.

  16. Depth Limits of Slow Slip Events at the Japan Trench: Insights from Friction Experiments under In-Situ Conditions

    NASA Astrophysics Data System (ADS)

    Sawai, M.; Niemeijer, A. R.; Hirose, T.; Spiers, C. J.

    2014-12-01

    Episodic tremor and slip occurred just before the 2011 Tohoku-oki earthquake on a shallow portion (less than 20 km depth) in the Tohoku subduction zone (Ito et al., 2013). The area where slow slip occurred overlapped with the seismogenic zone. To understand such diverse slip behaviour around the Japan Trench, not only the major earthquakes but also the slow slip events, it is essential to reveal the frictional properties of rocks distributed at the Tohoku subduction zone. We thus conducted friction experiments using a rotary shear apparatus on smectite-rich pelagic sediments retrieved from the plate-boundary thrust during IODP Expedition 343. The sediments were disaggregated and simulated gouges were then sheared at temperatures of 20-200oC, an effective normal stress of 50 MPa and a pore fluid pressure of 50 MPa. We conducted velocity-stepping sequences (0.3 to 100 μm/s) to determine the rate and state parameter (a-b) and investigated the effects of temperature and slip rate on slip stability.Our results show that at low temperatures of 20 and 50oC, the simulated gouges exhibit negative values of (a-b) with a background friction coefficient of 0.38, except at the highest slip rate of 0.1 mm/s. However, the gouges show neutral to positive values of (a-b) at temperatures of >100oC with the same background friction coefficient as at lower temperatures. In addition, the value of parameter (a-b) depends significantly on slip rates: at temperatures of 20 and 50oC it increases from negative to neutral (or slightly positive at 20oC) with increasing slip rates to 0.1 mm/s, whereas it tends to decrease with increasing slip rate at temperatures higher than 100oC. The downdip temperature limit of the slow slip events at Japan Trench (Ito et al., 2013) seems to be in the range between 100 to 150oC. The transition in (a-b) value from neutral to positive, particularly at lower slip rates, occurs at the same temperature range. Hence, this could correspond to the observed downdip

  17. The EPQ model under conditions of two levels of trade credit and limited storage capacity in supply chain management

    NASA Astrophysics Data System (ADS)

    Chung, Kun-Jen

    2013-09-01

    An inventory problem involves a lot of factors influencing inventory decisions. To understand it, the traditional economic production quantity (EPQ) model plays rather important role for inventory analysis. Although the traditional EPQ models are still widely used in industry, practitioners frequently question validities of assumptions of these models such that their use encounters challenges and difficulties. So, this article tries to present a new inventory model by considering two levels of trade credit, finite replenishment rate and limited storage capacity together to relax the basic assumptions of the traditional EPQ model to improve the environment of the use of it. Keeping in mind cost-minimisation strategy, four easy-to-use theorems are developed to characterise the optimal solution. Finally, the sensitivity analyses are executed to investigate the effects of the various parameters on ordering policies and the annual total relevant costs of the inventory system.

  18. Growth and photosynthetic limitation analysis of the Cd-accumulator Salicornia ramosissima under excessive cadmium concentrations and optimum salinity conditions.

    PubMed

    Pérez-Romero, Jesús Alberto; Redondo-Gómez, Susana; Mateos-Naranjo, Enrique

    2016-12-01

    Cadmium (Cd) is a non-essential element for plants, and its excess impairs plant performance. Physiological impacts of Cd excess are well known in non-tolerant plants, however this information is scarce for Cd-tolerant plants. A glasshouse experiment was designed to investigate the effect of five different Cd levels (0, 0.05, 0.20, 0.65 and 1.35 mM Cd) on the growth, photosynthetic apparatus (PSII chemistry), gas exchange characteristics, photosynthetic pigments profiles, water relations and nutritional balance of the Cd-accumulator Salicornia ramosissima. Ours results confirmed the accumulation capacity of S. ramosissima, as indicated the bioaccumulation factor (BC) greater than 1.0 for all Cd levels. Furthermore, after 21 days of treatment S. ramosissima growth was not highly affected by Cd. Total photosynthetic limitation increased from 38% at 0.05 mM Cd to 70% at 1.35 mM Cd. CO2 diffusion restriction imposed the main contribution to total photosynthetic limitation. Mesophyll conductance reduction was of major importance (with between 69 and 86%), followed by stomatal conductance (with between 9 and 20%). Maximum carboxylation rate (Vc,max), remained stable until 0.2 mM Cd, and chlorophyll fluorescence parameters (Fv/Fm, qP) and pigments concentrations were not significantly decreased by increased Cd supply. Finally, S. ramosissima water relations (intrinsic water use efficiency and relative water content) and nutritional level did not highly vary between Cd treatments. Thus, our finding suggested that Cd tolerance S. ramosissima is in certain degree supported by the tolerance of its carbon assimilation enzyme (RuBisCO) and with the high functionality and integrity of the PSII reaction center under Cd excess.

  19. Aggressive mimicry coexists with mutualism in an aphid.

    PubMed

    Salazar, Adrián; Fürstenau, Benjamin; Quero, Carmen; Pérez-Hidalgo, Nicolás; Carazo, Pau; Font, Enrique; Martínez-Torres, David

    2015-01-27

    Understanding the evolutionary transition from interspecific exploitation to cooperation is a major challenge in evolutionary biology. Ant-aphid relationships represent an ideal system to this end because they encompass a coevolutionary continuum of interactions ranging from mutualism to antagonism. In this study, we report an unprecedented interaction along this continuum: aggressive mimicry in aphids. We show that two morphs clonally produced by the aphid Paracletus cimiciformis during its root-dwelling phase establish relationships with ants at opposite sides of the mutualism-antagonism continuum. Although one of these morphs exhibits the conventional trophobiotic (mutualistic) relationship with ants of the genus Tetramorium, aphids of the alternative morph are transported by the ants to their brood chamber and cared for as if they were true ant larvae. Gas chromatography-mass spectrometry analyses reveal that the innate cuticular hydrocarbon profile of the mimic morph resembles the profile of ant larvae more than that of the alternative, genetically identical nonmimic morph. Furthermore, we show that, once in the brood chamber, mimic aphids suck on ant larva hemolymph. These results not only add aphids to the limited list of arthropods known to biosynthesize the cuticular chemicals of their deceived hosts to exploit their resources but describe a remarkable case of plastic aggressive mimicry. The present work adds a previously unidentified dimension to the classical textbook paradigm of aphid-ant relationships by showcasing a complex system at the evolutionary interface between cooperation and exploitation.

  20. Classical mutual information in mean-field spin glass models

    NASA Astrophysics Data System (ADS)

    Alba, Vincenzo; Inglis, Stephen; Pollet, Lode

    2016-03-01

    We investigate the classical Rényi entropy Sn and the associated mutual information In in the Sherrington-Kirkpatrick (S-K) model, which is the paradigm model of mean-field spin glasses. Using classical Monte Carlo simulations and analytical tools we investigate the S-K model in the n -sheet booklet. This is achieved by gluing together n independent copies of the model, and it is the main ingredient for constructing the Rényi entanglement-related quantities. We find a glassy phase at low temperatures, whereas at high temperatures the model exhibits paramagnetic behavior, consistent with the regular S-K model. The temperature of the paramagnetic-glassy transition depends nontrivially on the geometry of the booklet. At high temperatures we provide the exact solution of the model by exploiting the replica symmetry. This is the permutation symmetry among the fictitious replicas that are used to perform disorder averages (via the replica trick). In the glassy phase the replica symmetry has to be broken. Using a generalization of the Parisi solution, we provide analytical results for Sn and In and for standard thermodynamic quantities. Both Sn and In exhibit a volume law in the whole phase diagram. We characterize the behavior of the corresponding densities, Sn/N and In/N , in the thermodynamic limit. Interestingly, at the critical point the mutual information does not exhibit any crossing for different system sizes, in contrast with local spin models.

  1. Young adults as users of adult healthcare: experiences of young adults with complex or life-limiting conditions.

    PubMed

    Beresford, B; Stuttard, L

    2014-08-01

    Awareness is growing that young adults may have distinctive experiences of adult healthcare and that their needs may differ from those of other adult users. In addition, the role of adult health teams in supporting positive transitions from paediatrics is increasingly under discussion. This paper contributes to these debates. It reports a qualitative study of the experiences of young adults - all with complex chronic health conditions - as users of adult health services. Key findings from the study are reported, including an exploration of factors that help to explain interviewees' experiences. Study findings are discussed in the context of existing evidence from young adults in adult healthcare settings and theories of 'young adulthood'. Implications for training and practice are considered, and priorities for future research are identified.

  2. Predictive Simulation of Gas Adsorption in Fixed-Beds and Limitations due to the Ill-Posed Danckwerts Boundary Condition

    NASA Technical Reports Server (NTRS)

    Knox, James Clinton

    2016-01-01

    The 1-D axially dispersed plug flow model is a mathematical model widely used for the simulation of adsorption processes. Lumped mass transfer coefficients such as the Glueckauf linear driving force (LDF) term and the axial dispersion coefficient are generally obtained by fitting simulation results to the experimental breakthrough test data. An approach is introduced where these parameters, along with the only free parameter in the energy balance equations, are individually fit to specific test data that isolates the appropriate physics. It is shown that with this approach this model provides excellent simulation results for the C02 on zeolite SA sorbent/sorbate system; however, for the H20 on zeolite SA system, non-physical deviations from constant pattern behavior occur when fitting dispersive experimental results with a large axial dispersion coefficient. A method has also been developed that determines a priori what values of the LDF and axial dispersion terms will result in non-physical simulation results for a specific sorbent/sorbate system when using the one-dimensional axially dispersed plug flow model. A relationship between the steepness of the adsorption equilibrium isotherm as indicated by the distribution factor, the magnitude of the axial dispersion and mass transfer coefficient, and the resulting non-physical behavior is derived. This relationship is intended to provide a guide for avoiding non-physical behavior by limiting the magnitude of the axial dispersion term on the basis of the mass transfer coefficient and distribution factor.

  3. 2007 Mutual events within the binary system of (22) Kalliope

    NASA Astrophysics Data System (ADS)

    Descamps, P.; Marchis, F.; Pollock, J.; Berthier, J.; Birlan, M.; Vachier, F.; Colas, F.

    2008-11-01

    In 2007, the asteroid Kalliope will reach one of its annual equinoxes. As a consequence, its small satellite Linus orbiting in the equatorial plane will undergo a season of mutual eclipses and occultations very similar to the one that the Galilean satellites undergo every 6 years. This paper is aimed at preparing a campaign of observations of these mutual events occurring from February to May 2007. This opportunity occurs only under favorable geometric conditions when the Sun and/or the Earth are close to the orbital plane of the system. This is the first international campaign devoted to the observation of photometric events within an asynchronous asteroidal binary system. We took advantage of a reliable orbit solution of Linus to predict a series of 24 mutual eclipses and 12 mutual occultations observable in the spring of 2007. Thanks to the brightness of Kalliope ( mv≃11), these observations are easy to perform even with a small telescope. Anomalous attenuation events could be observed lasting for about 1-3 h with amplitude up to 0.09 mag. The attenuations are of two distinct types that can clearly be identified as primary and secondary eclipses similar to those that have been previously observed in other minor planet binary systems [Pravec, P., Scheirich, P., Kusnirák, P., Sarounová, L., Mottola, S., Hahn, G., Brown, P., Esquerdo, G., Kaiser, N., Krzeminski, Z., Pray, D.P., Warner, B.D., Harris, A.W., Nolan, M.C., Howell, E.S., Benner, L.A.M., Margot, J.-L., Galád, A., Holliday, W., Hicks, M.D., Krugly, Yu.N., Tholen, D., Whiteley, R., Marchis, F., Degraff, D.R., Grauer, A., Larson, S., Velichko, F.P., Cooney, W.R., Stephens, R., Zhu, J., Kirsch, K., Dyvig, R., Snyder, L., Reddy, V., Moore, S., Gajdos, S., Világi, J., Masi, G., Higgins, D., Funkhouser, G., Knight, B., Slivan, S., Behrend, R., Grenon, M., Burki, G., Roy, R., Demeautis, C., Matter, D., Waelchli, N., Revaz, Y., Klotz, A., Rieugné, M., Thierry, P., Cotrez, V., Brunetto, L., Kober, G., 2006

  4. Tenax extraction for exploring rate-limiting factors in methyl-β-cyclodextrin enhanced anaerobic biodegradation of PAHs under denitrifying conditions in a red paddy soil.

    PubMed

    Sun, Mingming; Ye, Mao; Hu, Feng; Li, Huixin; Teng, Ying; Luo, Yongming; Jiang, Xin; Kengara, Fredrick Orori

    2014-01-15

    The effectiveness of anaerobic bioremediation systems for PAH-contaminated soil may be constrained by low contaminants bioaccessibility due to limited aqueous solubility and lack of suitable electron acceptors. Information on what is the rate-limiting factor in bioremediation process is of vital importance in the decision in what measures can be taken to assist the biodegradation efficacy. In the present study, four different microcosms were set to study the effect of methyl-β-cyclodextrin (MCD) and nitrate addition (N) on PAHs biodegradation under anaerobic conditions in a red paddy soil. Meanwhile, sequential Tenax extraction combined with a first-three-compartment model was employed to evaluate the rate-limiting factors in MCD enhanced anaerobic biodegradation of PAHs. Microcosms with both 1% (w/w) MCD and 20mM N addition produced maximum biodegradation of total PAHs of up to 61.7%. It appears rate-limiting factors vary with microcosms: low activity of degrading microorganisms is the vital rate-limiting factor for control and MCD addition treatments (CK and M treatments); and lack of bioaccessible PAHs is the main rate-limiting factor for nitrate addition treatments (N and MN treatments). These results have practical implications for site risk assessment and cleanup strategies.

  5. Nitrogen availability impacts oilseed rape (Brassica napus L.) plant water status and proline production efficiency under water-limited conditions.

    PubMed

    Albert, Benjamin; Le Cahérec, Françoise; Niogret, Marie-Françoise; Faes, Pascal; Avice, Jean-Christophe; Leport, Laurent; Bouchereau, Alain

    2012-08-01

    Large amounts of nitrogen (N) fertilizers are used in the production of oilseed rape. However, as low-input methods of crop management are introduced crops will need to withstand temporary N deficiency. In temperate areas, oilseed rape will also be affected by frequent drought periods. Here we evaluated the physiological and metabolic impact of nitrate limitation on the oilseed rape response to water deprivation. Different amounts of N fertilizer were applied to plants at the vegetative stage, which were then deprived of water and rehydrated. Both water and N depletion accelerated leaf senescence and reduced leaf development. N-deprived plants exhibited less pronounced symptoms of wilting during drought, probably because leaves were smaller and stomata were partially closed. Efficiency of proline production, a major stress-induced diversion of nitrogen metabolism, was assessed at different positions along the whole plant axis and related to leaf developmental stage and water status indices. Proline accumulation, preferentially in younger leaves, accounted for 25-85% of the free amino acid pool. This was mainly due to a better capacity for proline synthesis in fully N-supplied plants whether they were subjected to drought or not, as deduced from the expression patterns of the proline metabolism BnP5CS and BnPDH genes. Although less proline accumulated in the oldest leaves, a significant amount was transported from senescing to emerging leaves. Moreover, during rehydration proline was readily recycled. Our results therefore suggest that proline plays a significant role in leaf N remobilization and in N use efficiency in oilseed rape.

  6. Limited Clinical Utility of Remote Ischemic Conditioning in Renal Transplantation: A Meta-Analysis of Randomized Controlled Trials

    PubMed Central

    Wu, Ran; Xin, Hui; Lu, Tian-Ze; Li, Ming-Hao; Song, Kai-Wei; Wang, Min; Zhu, Yun-Peng; Zhu, Meng; Geng, Li-Guo; Gao, Xiao-Fei; Zhou, Liu-Hua; Zhang, Sheng-Li; Zhu, Jia-Geng; Jia, Rui-Peng

    2017-01-01

    Objective We conducted this meta-analysis of randomized controlled trials (RCTs) to investigate whether remote ischemic conditioning (RIC) could improve graft functions in kidney transplantation. Methods PubMed, Web of Science, and Cochrane Library were comprehensively searched to identify all eligible studies by October 5, 2016. The treatment effects were examined with risk ratio (RR) and weighted mean difference with the corresponding 95% confidence intervals (CI). The statistical significance and heterogeneity were assessed with both Z-test and Q-test. Results A total of six RCTs including 651 recipients, were eventually identified. Compared to the controls, RIC could reduce the incidence of delayed graft function (DGF) after kidney transplantation (random-effects model: RR = 0.89; fixed-effect model: RR = 0.84). However, the decrease did not reveal statistical significance. The subgroup analysis by RIC type demonstrated no significant difference among the three interventions in protecting renal allografts against DGF. Furthermore, no significant difference could be observed in the incidence of acute rejection, graft loss, 50% fall in serum creatinine, as well as the estimated glomerular filtration rate and hospital stay between the RIC and Control groups. Conclusions This meta-analysis suggested that RIC might exert renoprotective functions in human kidney transplantation, and further well-designed RCTs with large sample size are warranted to assess its clinical efficacy. PMID:28129389

  7. Medical Underwriting In Long-Term Care Insurance: Market Conditions Limit Options For Higher-Risk Consumers.

    PubMed

    Cornell, Portia Y; Grabowski, David C; Cohen, Marc; Shi, Xiaomei; Stevenson, David G

    2016-08-01

    A key feature of private long-term care insurance is that medical underwriters screen out would-be buyers who have health conditions that portend near-term physical or cognitive disability. We applied common underwriting criteria based on data from two long-term care insurers to a nationally representative sample of individuals in the target age range (50-71 years) for long-term care insurance. The screening criteria put upper bounds on the current proportion of Americans who could gain coverage in the individual market without changes to medical underwriting practice. Specifically, our simulations show that in the target age range, approximately 30 percent of those whose wealth meets minimum industry standards for suitability for long-term care insurance would have their application for such insurance rejected at the underwriting stage. Among the general population-without considering financial suitability-we estimated that 40 percent would have their applications rejected. The predicted rejection rates are substantially higher than the rejection rates of about 20-25 percent of applicants in the actual market. In evaluating reforms for long-term care financing and their potential to increase private insurance rates, as well as to reduce financial pressure on public safety-net programs, policy makers need to consider the role of underwriting in the market for long-term care insurance.

  8. Cell-cell and cell-surface interactions mediated by cellulose and a novel exopolysaccharide contribute to Pseudomonas putida biofilm formation and fitness under water-limiting conditions.

    PubMed

    Nielsen, Lindsey; Li, Xiaohong; Halverson, Larry J

    2011-05-01

    The composition of the exopolysaccharide matrix of Pseudomonas putida mt2 biofilms is relatively undefined as well as the contributions of each polymer to ecological fitness. Here, we describe the role of two putative exopolysaccharide gene clusters, putida exopolysaccharide A (pea) and bacterial cellulose (bcs) in biofilm formation and stability, rhizosphere colonization and matrix hydration under water-limiting conditions. Our findings suggest that pea is involved in the production of a novel glucose, galactose, and mannose-rich polymer that contributes to cell-cell interactions necessary for pellicle and biofilm formation and stability. In contrast, Bcs plays a minor role in biofilm formation and stability, although it does contribute to rhizosphere colonization based on a competition assay. We show that pea expression is highly induced transiently under water-limiting conditions but only slightly by high osmolarity, as determined by qRT-PCR. In contrast, both forms of water stress highly induced bcs expression. Cells deficient in making one or more exopolysaccharide experienced greater dehydration-mediated cell-envelope stress, leading to increased alginate promoter activity. However, this did not lead to increased exopolysaccharide production, except in bcs or pea mutants unable to produce alginate, indicating that P. putida compensates by producing, presumably more Pea or Bcs exopolysaccharides, to facilitate biofilm hydration. Collectively, the data suggest that Pea and Bcs contribute to biofilm formation and in turn their presence contributes to fitness under water-limiting conditions, but not to the extent of alginate.

  9. Identity theory and personality theory: mutual relevance.

    PubMed

    Stryker, Sheldon

    2007-12-01

    Some personality psychologists have found a structural symbolic interactionist frame and identity theory relevant to their work. This frame and theory, developed in sociology, are first reviewed. Emphasized in the review are a multiple identity conception of self, identities as internalized expectations derived from roles embedded in organized networks of social interaction, and a view of social structures as facilitators in bringing people into networks or constraints in keeping them out, subsequently, attention turns to a discussion of the mutual relevance of structural symbolic interactionism/identity theory and personality theory, looking to extensions of the current literature on these topics.

  10. Creating a culture of mutual respect.

    PubMed

    Kaplan, Kathryn; Mestel, Pamela; Feldman, David L

    2010-04-01

    The Joint Commission mandates that hospitals seeking accreditation have a process to define and address disruptive behavior. Leaders at Maimonides Medical Center, Brooklyn, New York, took the initiative to create a code of mutual respect that not only requires respectful behavior, but also encourages sensitivity and awareness to the causes of frustration that often lead to inappropriate behavior. Steps to implementing the code included selecting code advocates, setting up a system for mediating disputes, tracking and addressing operational system issues, providing training for personnel, developing a formal accountability process, and measuring the results.

  11. Hiding Planets behind a Big Friend: Mutual Inclinations of Multi-planet Systems with External Companions

    NASA Astrophysics Data System (ADS)

    Lai, Dong; Pu, Bonan

    2017-01-01

    The Kepler mission has detected thousands of planetary systems with one to seven transiting planets packed within 0.7 au from their host stars. There is an apparent excess of single-transit planet systems that cannot be explained by transit geometries alone, when a single planetary mutual inclination dispersion is assumed. This suggests that the observed compact planetary systems have at least two different architectures. We present a scenario where the “Kepler dichotomy” may be explained by the action of an external giant planet or stellar companion misaligned with the inner multi-planet system. The external companion excites mutual inclinations of the inner planets, causing such systems to appear as “Kepler singles” in transit surveys. We derive approximate analytic expressions (in various limiting regimes), calibrated with numerical calculations, for the mutual inclination excitations for various planetary systems and perturber properties (mass mp, semimajor axis ap, and inclination {θ }p). In general, the excited mutual inclination increases with {m}p/{a}p3 and {θ }p, though secular resonances may lead to large mutual inclinations even for small {θ }p. We discuss the implications of our results for understanding the dynamical history of transiting planet systems with known external perturbers.

  12. Steady-State Growth under Inorganic Carbon Limitation Conditions Increases Energy Consumption for Maintenance and Enhances Nitrous Oxide Production in Nitrosomonas europaea

    PubMed Central

    Giguere, Andrew; Chaplen, Frank; Bottomley, Peter J.

    2016-01-01

    ABSTRACT Nitrosomonas europaea is a chemolithoautotrophic bacterium that oxidizes ammonia (NH3) to obtain energy for growth on carbon dioxide (CO2) and can also produce nitrous oxide (N2O), a greenhouse gas. We interrogated the growth, physiological, and transcriptome responses of N. europaea to conditions of replete (>5.2 mM) and limited inorganic carbon (IC) provided by either 1.0 mM or 0.2 mM sodium carbonate (Na2CO3) supplemented with atmospheric CO2. IC-limited cultures oxidized 25 to 58% of available NH3 to nitrite, depending on the dilution rate and Na2CO3 concentration. IC limitation resulted in a 2.3-fold increase in cellular maintenance energy requirements compared to those for NH3-limited cultures. Rates of N2O production increased 2.5- and 6.3-fold under the two IC-limited conditions, increasing the percentage of oxidized NH3-N that was transformed to N2O-N from 0.5% (replete) up to 4.4% (0.2 mM Na2CO3). Transcriptome analysis showed differential expression (P ≤ 0.05) of 488 genes (20% of inventory) between replete and IC-limited conditions, but few differences were detected between the two IC-limiting treatments. IC-limited conditions resulted in a decreased expression of ammonium/ammonia transporter and ammonia monooxygenase subunits and increased the expression of genes involved in C1 metabolism, including the genes for RuBisCO (cbb gene cluster), carbonic anhydrase, folate-linked metabolism of C1 moieties, and putative C salvage due to oxygenase activity of RuBisCO. Increased expression of nitrite reductase (gene cluster NE0924 to NE0927) correlated with increased production of N2O. Together, these data suggest that N. europaea adapts physiologically during IC-limited steady-state growth, which leads to the uncoupling of NH3 oxidation from growth and increased N2O production. IMPORTANCE Nitrification, the aerobic oxidation of ammonia to nitrate via nitrite, is an important process in the global nitrogen cycle. This process is generally dependent

  13. Prior Knowledge Facilitates Mutual Gaze Convergence and Head Nodding Synchrony in Face-to-face Communication

    PubMed Central

    Thepsoonthorn, C.; Yokozuka, T.; Miura, S.; Ogawa, K.; Miyake, Y.

    2016-01-01

    As prior knowledge is claimed to be an essential key to achieve effective education, we are interested in exploring whether prior knowledge enhances communication effectiveness. To demonstrate the effects of prior knowledge, mutual gaze convergence and head nodding synchrony are observed as indicators of communication effectiveness. We conducted an experiment on lecture task between lecturer and student under 2 conditions: prior knowledge and non-prior knowledge. The students in prior knowledge condition were provided the basic information about the lecture content and were assessed their understanding by the experimenter before starting the lecture while the students in non-prior knowledge had none. The result shows that the interaction in prior knowledge condition establishes significantly higher mutual gaze convergence (t(15.03) = 6.72, p < 0.0001; α = 0.05, n = 20) and head nodding synchrony (t(16.67) = 1.83, p = 0.04; α = 0.05, n = 19) compared to non-prior knowledge condition. This study reveals that prior knowledge facilitates mutual gaze convergence and head nodding synchrony. Furthermore, the interaction with and without prior knowledge can be evaluated by measuring or observing mutual gaze convergence and head nodding synchrony. PMID:27910902

  14. The ColRS system of Xanthomonas oryzae pv. oryzae is required for virulence and growth in iron-limiting conditions.

    PubMed

    Subramoni, Sujatha; Pandey, Alok; Vishnu Priya, M R; Patel, Hitendra Kumar; Sonti, Ramesh V

    2012-09-01

    Xanthomonas oryzae pv. oryzae, the causal agent of bacterial blight of rice, produces siderophores only under iron-limiting conditions. We screened 15 400 mTn5-induced mutants of X. oryzae pv. oryzae and isolated 27 mutants that produced siderophores even under iron-replete conditions. We found that the mTn5 insertions in 25 of these mutants were in or close to six genes. Mutants with insertions in five of these genes [colS, XOO1806 (a conserved hypothetical protein), acnB, prpR and prpB] exhibited a deficiency for growth on iron-limiting medium and a decrease in virulence. Insertions in a sixth gene, XOO0007 (a conserved hypothetical protein), were found to affect the ability to grow on iron-limiting medium, but did not affect the virulence. Targeted gene disruptants for colR (encoding the predicted cognate regulatory protein for ColS) also exhibited a deficiency for growth on iron-limiting medium and a decrease in virulence. colR and colS mutants were defective in the elicitation of hypersensitive response symptoms on the nonhost tomato. In addition, colR and colS mutants induced a rice basal defence response, suggesting that they are compromised in the suppression of host innate immunity. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis demonstrated that a functional ColRS system is required for the optimal expression of several genes encoding components of the type 3 secretion system (T3SS) of X. oryzae pv. oryzae. Our results demonstrate the role of several novel genes, including colR/colS, in the promotion of growth on iron-limiting medium and the virulence of X. oryzae pv. oryzae.

  15. Generalized mutual information of quantum critical chains

    NASA Astrophysics Data System (ADS)

    Alcaraz, F. C.; Rajabpour, M. A.

    2015-04-01

    We study the generalized mutual information I˜n of the ground state of different critical quantum chains. The generalized mutual information definition that we use is based on the well established concept of the Rényi divergence. We calculate this quantity numerically for several distinct quantum chains having either discrete Z (Q ) symmetries (Q -state Potts model with Q =2 ,3 ,4 and Z (Q ) parafermionic models with Q =5 ,6 ,7 ,8 and also Ashkin-Teller model with different anisotropies) or the U (1 ) continuous symmetries (Klein-Gordon field theory, X X Z and spin-1 Fateev-Zamolodchikov quantum chains with different anisotropies). For the spin chains these calculations were done by expressing the ground-state wave functions in two special bases. Our results indicate some general behavior for particular ranges of values of the parameter n that defines I˜n. For a system, with total size L and subsystem sizes ℓ and L -ℓ , the I˜n has a logarithmic leading behavior given by c/˜n4 log[L/π sin(π/ℓ L ) ] where the coefficient c˜n is linearly dependent on the central charge c of the underlying conformal field theory describing the system's critical properties.

  16. Collective Dynamics on a Two-Lane Asymmetrically Coupled TASEP with Mutually Interactive Langmuir Kinetics

    NASA Astrophysics Data System (ADS)

    Gupta, Arvind Kumar

    2016-03-01

    Motivated by the recent experimental observations on clustering of motor proteins on microtubule filament, we study an open system of two parallel totally asymmetric simple exclusion processes under asymmetric coupling conditions, which incorporates the mutual interaction with the surrounding environment through Langmuir Kinetics (LK) in both the lanes. In the modified LK, the attachment and detachment rates depends on the configuration of nearest neighboring sites. We analyse the model within the framework of continuum mean-field theory and the phase diagrams along with density profiles are obtained using boundary layer analysis. The effect of mutual interactions on the phase diagram for two different situations of attachment and detachment (LK) rates is discussed. Under the symmetric LK dynamics, the topological structure of the phase diagram remains similar to the one in without mutual interaction; while for the antisymmetric case, after a certain critical value of attractive/repulsive mutual attraction, significant changes are found in the qualitative nature of phase diagram. Moreover, it is shown that the type of mutual interaction affects the dynamic properties of motor proteins. The theoretical findings are examined by extensive Monte-Carlo simulations.

  17. Decrease of Mutual Information in Brain Electrical Activity of Patients with Relapsing-Remitting Multiple Sclerosis

    PubMed Central

    Lenne, Bruno; Blanc, Jean-Luc; Nandrino, Jean-Louis; Gallois, Philippe; Hautecæur, Patrick; Pezard, Laurent

    2013-01-01

    The disturbance of cortical communication has been hypothesized as an important factor in the appearance of cognitive impairment in (MS). Cortical communication is quantified here in control subjects and patients with relapsing-remitting multiple sclerosis (RRMS) on the basis of mean coherence in the δ, θ, α, β and γ bands and using mutual information computed between pairs of bipolar EEG signals recorded during resting condition. Each patient received also a cognitive assessment using a battery of neuropsychological tests specific to cognitive deficits in MS. No difference was observed for the coherence indices whereas inter-hemispheric and right hemisphere mutual information is significantly lower in patients with MS than in control subjects. Moreover, inter-hemispheric mutual information decrease significantly with illness duration and right mutual information differentiate cognitively deficient and non-deficient patients. Mutual information allows to quantify the cortical communication in patients with RRMS and is related to clinical characteristics. Cortical communication quantified in a resting state might be a potential marker for the neurological damage induced by RRMS. PMID:23242355

  18. Bad guys turned nice? A critical assessment of Wolbachia mutualisms in arthropod hosts.

    PubMed

    Zug, Roman; Hammerstein, Peter

    2015-02-01

    Wolbachia are the most abundant bacterial endosymbionts among arthropods. Although maternally inherited, they do not conform to the widespread view that vertical transmission inevitably selects for beneficial symbionts. Instead, Wolbachia are notorious for their reproductive parasitism which, although lowering host fitness, ensures their spread. However, even for reproductive parasites it can pay to enhance host fitness. Indeed, there is a recent upsurge of reports on Wolbachia-associated fitness benefits. Therefore, the question arises how such instances of mutualism are related to the phenotypes of reproductive parasitism. Here, we review the evidence of Wolbachia mutualisms in arthropods, including both facultative and obligate relationships, and critically assess their biological relevance. Although many studies report anti-pathogenic effects of Wolbachia, few actually prove these effects to be relevant to field conditions. We further show that Wolbachia frequently have beneficial and detrimental effects at the same time, and that reproductive manipulations and obligate mutualisms may share common mechanisms. These findings undermine the idea of a clear-cut distinction between Wolbachia mutualism and parasitism. In general, both facultative and obligate mutualisms can have a strong, and sometimes unforeseen, impact on the ecology and evolution of Wolbachia and their arthropod hosts. Acknowledging this mutualistic potential might be the key to a better understanding of some unresolved issues in the study of Wolbachia-host interactions.

  19. Effects of cocaine self-administration history under limited and extended access conditions on in vivo striatal dopamine neurochemistry and acoustic startle in rhesus monkeys

    PubMed Central

    Henry, Porche’ Kirkland; Davis, Michael

    2009-01-01

    Rationale The transition from infrequent and controlled cocaine use to dependence may involve enduring changes in neurobiology as a consequence of persistent drug use. Objective The present study utilized an intravenous drug self-administration protocol of increasing cocaine access to evaluate potential changes in dopamine function in vivo, including changes in sensitivity to psychostimulants. Materials and methods Drug-naïve rhesus monkeys were provided limited access (1 h) to cocaine self-administration for 60 days followed by 60 days under an extended access condition (4 h). Basal levels of striatal extracellular dopamine and its metabolites, as well as the effectiveness of cocaine and amphetamine to elevate dopamine, were determined with in vivo microdialysis before the initiation of cocaine self-administration and during limited and extended access. The effect of cocaine and amphetamine on the acoustic startle response was also examined to assess complementary behavioral changes as a function of drug history. Results Extended access to cocaine self-administration lead to increased daily intake compared to limited access conditions but did not result in escalated intake over time. However, cocaine- and amphetamine-induced increases in striatal dopamine were diminished as a function of cocaine self-administration history. Surprisingly, there was no effect of drug-taking history on sensitivity to psychostimulant-induced enhancement of startle amplitude. Conclusions The present experiments provide evidence of a hypofunctional dopamine system that is not associated with an escalation in drug intake or reflected in measures of acoustic startle. PMID:19365621

  20. Metabolic Flux Analysis of the Synechocystis sp. PCC 6803 ΔnrtABCD Mutant Reveals a Mechanism for Metabolic Adaptation to Nitrogen-Limited Conditions.

    PubMed

    Nakajima, Tsubasa; Yoshikawa, Katsunori; Toya, Yoshihiro; Matsuda, Fumio; Shimizu, Hiroshi

    2017-03-01

    Metabolic flux redirection during nitrogen-limited growth was investigated in the Synechocystis sp. PCC 6803 glucose-tolerant (GT) strain under photoautotrophic conditions by isotopically non-stationary metabolic flux analysis (INST-MFA). A ΔnrtABCD mutant of Synechocystis sp. PCC 6803 was constructed to reproduce phenotypes arising during nitrogen starvation. The ΔnrtABCD mutant and the wild-type GT strain were cultured under photoautotrophic conditions by a photobioreactor. Intracellular metabolites were labeled over a time course using NaH13CO3 as a carbon source. Based on these data, the metabolic flux distributions in the wild-type and ΔnrtABCD cells were estimated by INST-MFA. The wild-type GT and ΔnrtABCD strains displayed similar distribution patterns, although the absolute levels of metabolic flux were lower in ΔnrtABCD. Furthermore, the relative flux levels for glycogen metabolism, anaplerotic reactions and the oxidative pentose phosphate pathway were increased in ΔnrtABCD. This was probably due to the increased expression of enzyme genes that respond to nitrogen depletion. Additionally, we found that the ratio of ATP/NADPH demand increased slightly in the ΔnrtABCD mutant. These results indicated that futile ATP consumption increases under nitrogen-limited conditions because the Calvin-Benson cycle and the oxidative pentose phosphate pathway form a metabolic futile cycle that consumes ATP without CO2 fixation and NADPH regeneration.

  1. Online analysis of single cyanobacteria and algae cells under nitrogen-limited conditions using aerosol time-of-flight mass spectrometry.

    PubMed

    Cahill, John F; Darlington, Thomas K; Fitzgerald, Christine; Schoepp, Nathan G; Beld, Joris; Burkart, Michael D; Prather, Kimberly A

    2015-08-18

    Metabolomics studies typically perform measurements on populations of whole cells which provide the average representation of a collection of many cells. However, key mechanistic information can be lost using this approach. Investigating chemistry at the single cell level yields a more accurate representation of the diversity of populations within a cell sample; however, this approach has many analytical challenges. In this study, an aerosol time-of-flight mass spectrometer (ATOFMS) was used for rapid analysis of single algae and cyanobacteria cells with diameters ranging from 1 to 8 μm. Cells were aerosolized by nebulization and directly transmitted into the ATOFMS. Whole cells were determined to remain intact inside the instrument through a combination of particle sizing and imaging measurements. Differences in cell populations were observed after perturbing Chlamydomonas reinhardtii cells via nitrogen deprivation. Thousands of single cells were measured over a period of 4 days for nitrogen-replete and nitrogen-limited conditions. A comparison of the single cell mass spectra of the cells sampled under the two conditions revealed an increase in the dipalmitic acid sulfolipid sulfoquinovosyldiacylglycerol (SQDG), a chloroplast membrane lipid, under nitrogen-limited conditions. Single cell peak intensity distributions demonstrate the ability of the ATOFMS to measure metabolic differences of single cells. The ATOFMS provides an unprecedented maximum throughput of 50 Hz, enabling the rapid online measurement of thousands of single cell mass spectra.

  2. Orthopedic, ophthalmic, and psychiatric diseases primarily affect activity limitation for Japanese males and females: Based on the Comprehensive Survey of Living Conditions

    PubMed Central

    Myojin, Tomoya; Ojima, Toshiyuki; Kikuchi, Keiko; Okada, Eisaku; Shibata, Yosuke; Nakamura, Mieko; Hashimoto, Shuji

    2016-01-01

    Background Healthy life expectancy (HLE) is used as one of the primary objectives of fundamental health promotion plans and social development plans. Activity limitation is used to calculate HLE, but little study has been done to identify determinants of activity limitation in order to extend HLE. The purpose of this study is to identify diseases and injuries that commonly lead to activity limitation to prioritize countermeasures against activity limitation. Methods We used anonymous data from the 2007 “Comprehensive Survey of Living Conditions,” collected by the Ministry of Health, Labour and Welfare of Japan according to the Statistics Act, Article 36. We used logistic regression analyses and calculated odds ratios (ORs) after adjusting for age and sex. Limitation in daily activities was applied as the dependent variable, and each disease/injury was applied as an independent variable in this analysis. Furthermore, population attributable fractions (PAFs) were calculated. Results The provided data included 98,789 subjects. We used data for 75,986 valid subjects aged 12 years or older. The following diseases showed high PAF: backache (PAF 13.27%, OR 3.88), arthropathia (PAF 7.61%, OR 4.82), eye and optical diseases (PAF 6.39%, OR 2.01), and depression and other mental diseases (PAF 5.70%, OR 11.55). PAFs of cerebrovascular diseases, hypertension, and diabetes were higher for males than for females; on the other hand, PAFs of orthopedic diseases were higher among females. Conclusions Our results indicate that orthopedic diseases, ophthalmic diseases, and psychiatric diseases particularly affect activity limitation. PMID:28142015

  3. A Comprehensive Approach to Assess Arabidopsis Survival Phenotype in Water-Limited Condition Using a Non-invasive High-Throughput Phenomics Platform

    PubMed Central

    Vello, Emilio; Tomita, Akiko; Diallo, Amadou Oury; Bureau, Thomas E.

    2015-01-01

    With the rapid rise in global population and the challenges caused by climate changes, the maximization of plant productivity and the development of sustainable agriculture strategies are vital for food security. One of the resources more affected in this new environment will be the limitation of water. In this study, we describe the use of non-invasive technologies exploiting sensors for visible, fluorescent, and near-infrared lights to accurately screen survival phenotypes in Arabidopsis thaliana exposed to water-limited conditions. We implemented two drought protocols and a robust analysis methodology that enabled us to clearly assess the wilting or dryness status of the plants at different time points using a phenomics platform. In conclusion, our approach has shown to be very accurate and suitable for experiments where hundred of samples have to be screened making a manual evaluation unthinkable. This approach can be used not only in functional genomics studies but also in agricultural applications. PMID:26697051

  4. Investigation of the physiological response to oxygen limited process conditions of Pichia pastoris Mut(+) strain using a two-compartment scale-down system.

    PubMed

    Lorantfy, Bettina; Jazini, Mohammadhadi; Herwig, Christoph

    2013-09-01

    Inhomogeneities in production-scale bioreactors influence microbial growth and product quality due to insufficient mixing and mass transfer. For this reason, lots of efforts are being made to investigate the effects of gradients that impose stress in large-scale reactors in laboratory scale. We have implemented a scale-down model which allows separating a homogeneous part, a stirred tank reactor (STR), and a plug flow reactor (PFR) which mimics the inhomogeneous regimes of the large-scale fermenters. This scale-down model shows solutions to trigger oxygen limited conditions in the PFR part of the scale-down setup for physiological analysis. The goal of the study was to investigate the scale-up relevant physiological responses of Pichia pastoris strain to oxygen limited process conditions in the above mentioned two-compartment bioreactor setup. Experimental results with non-induced cultures show that the specific growth rate significantly decreased with increasing the exposure time to oxygen limitation. In parallel more by-products were produced. Examining physiological scalable key parameters, multivariate data analyses solely using on-line data revealed that different exposures to the oxygen limitation significantly affected the culture performance. This work with the small scale-downs setup reflects new approaches for a valuable process development tool for accelerating strain characterization or for verifying CFD simulations of large-scale bioreactors. As a novel methodological achievement, the combination of the two-compartment scale-down system with the proposed multivariate techniques of solely using on-line data is a valuable tool for recognition of stress effects on the culture performance for physiological bioprocess scale-up issues.

  5. Effect of Fuel Composition, Engine Operating Variables, and Spark-Plug Type and Condition on Preignition-Limited Performance of an R-2800 Cylinder

    NASA Technical Reports Server (NTRS)

    Pfender, John F.

    1946-01-01

    The preignition characteristics of the R-2800 cylinder, as effected by fuel consumption, engine operating variables, and spark plug type and condition, were evaluated. The effects on preignition-limited performance of various percentages of aromatics (benzene, toluene, cumene, xylene) in a base fuel of triptane were investigated. Two paraffins (triptane and S + 6.0 ml TEL/gal) and two refinery blends (28-R and 33-R) were preignition rated. The effect of changes in the following engine operating variables on preignition limit was determined: inlet-air temperature, rear spark plug gasket temperature, engine speed, spark advance, tappet clearance, and oil consumption. Preignition limits of the R-2800 cylinder using Champion C34S and C35S and AC-LS86, LS87, and LS88 spark plugs were established and the effect of spark plug deterioration was investigated. No definite trends in preignition-limited indicated mean effective pressure were indicated for aromatics as a class when increased percentages of different aromatics were added to a base fuel of triptane. Three types of fuel (aromatics, paraffins, and refinery blends) showed a preignition range for this cylinder from 65 to 104 percent when based on the performance of S plus 6.0 ml TEL per gallon as 100 percent. The R-2800 cylinder is therefore relatively insensitive to fuel composition when compared to a CFR F-4 engine, which had a pre-ignition range from 72 to 100 percent for the same fuels. Six engine operating variables were investigated with the following results: preignition-limited indicated mean effective pressure decreased, with increases in engine speed, rear spark plug gasket temperature, inlet-air temperature, and spark advance beyond 20 F B.T.C. and was unaffected by rate of oil consumption or by tappet clearance. Spark plugs were rated over a range of preignition-limited indicated mean effective pressure from 200 to 390 pounds per square inch at a fuel-air ratio of 0.07 in the following order of increased

  6. Controls on dissolved organic matter (DOM) degradation in a headwater stream: the influence of photochemical and hydrological conditions in determining light-limitation or substrate-limitation of photo-degradation

    NASA Astrophysics Data System (ADS)

    Cory, R. M.; Harrold, K. H.; Neilson, B. T.; Kling, G. W.

    2015-11-01

    -degradation is "light-limited" or "substrate-limited". We suggest that degradation of DOM in CDOM-rich streams or ponds similar to Imnavait is typically light-limited under most flow conditions. Thus, export of DOM from this stream will be less under conditions that increase the light available for DOM photo-degradation (i.e., low flows, sunny days).

  7. Method to identify potential phosphorus rate-limiting conditions in post-denitrification biofilm reactors within systems designed for simultaneous low-level effluent nitrogen and phosphorus concentrations.

    PubMed

    Boltz, Joshua P; Morgenroth, Eberhard; Daigger, Glen T; deBarbadillo, Christine; Murthy, Sudhir; Sørensen, Kim H; Stinson, Beverly

    2012-12-01

    Water-quality standards requiring simultaneous low level effluent N and P concentrations are increasingly common in Europe and the United States of America. Moving bed biofilm reactors (MBBRs) and biologically active filters (BAFs) have been used as post-denitrification biofilm reactors in processes designed and operated for this purpose (Boltz et al., 2010a). There is a paucity of information describing systematic design and operational protocols that will minimize the potential for phosphorus rate-limited conditions as well as a lack of information describing the interaction between these post-denitrification biofilm reactors and unit processes that substantially alter phosphorus speciation (e.g., chemically enhanced clarification). In this paper, a simple mathematical model for estimating the threshold below which P becomes rate-limiting, and the model is presented and evaluated by comparing its predictions with operational data from post-denitrification MBBRs and BAFs. Ortho-phosphorus (PO(4)-P), which is the dissolved reactive component of total phosphorus, was a primary indicator of P rate-limiting conditions in the evaluated post-denitrification biofilm reactors. The threshold below which PO(4)-P becomes the rate-limiting substrate is defined: S(PO4-P):S(NOx-N) = 0.0086 g P/g N and S(PO4-P):S(M) = 0.0013 g P/g COD. Additional analyses indicate J(NOx-N)(avg) =0.48 g/m2/d when S(PO4-P):S(NOx-N) > 0.0086, and J(NOx-N)(avg) = 0.06 g/m2/d when S(PO4-P):S(NOx-N) < 0.0086. Effluent nitrate-nitrogen plus nitrite-nitrogen concentration (S(NOx-N)) from the evaluated post-denitrification biofilm reactors began to rapidly increase when S(PO4-P):S(NOx-N) was 0.01, approximately (consistent with the rate-limitation threshold of S(PO4-P):S(NOx-N) < 0.0086 predicted by the mathematical model described in this paper). Depending on the processes used at a given WWTP, optimizing chemically enhanced clarification to increase the amount of PO(4)-P that remains in the clarifiers

  8. Mutual information-based facial expression recognition

    NASA Astrophysics Data System (ADS)

    Hazar, Mliki; Hammami, Mohamed; Hanêne, Ben-Abdallah

    2013-12-01

    This paper introduces a novel low-computation discriminative regions representation for expression analysis task. The proposed approach relies on interesting studies in psychology which show that most of the descriptive and responsible regions for facial expression are located around some face parts. The contributions of this work lie in the proposition of new approach which supports automatic facial expression recognition based on automatic regions selection. The regions selection step aims to select the descriptive regions responsible or facial expression and was performed using Mutual Information (MI) technique. For facial feature extraction, we have applied Local Binary Patterns Pattern (LBP) on Gradient image to encode salient micro-patterns of facial expressions. Experimental studies have shown that using discriminative regions provide better results than using the whole face regions whilst reducing features vector dimension.

  9. Concurrent behavior: Are the interpretations mutually exclusive?

    PubMed Central

    Lyon, David O.

    1982-01-01

    The experimental literature is replete with examples of behavior which occur concurrently with a schedule of reinforcement. These concurrent behaviors, often with similar topographies and occurring under like circumstances, may be interpreted as functionally autonomous, collateral, adjunctive, superstitious or mediating behavior. The degree to which the interaction of concurrent and schedule controlled behavior is used in the interpretation of behavior illustrated the importance of distinguishing among these interpretations by experimental procedure. The present paper reviews the characteristics of these interpretations, and discusses the experimental procedures necessary to distinguish among them. The paper concludes that the interpretations are mutually exclusive and refer to distinct behaviors, but that the distinction between any two of the interpretations requires more than one experimental procedure. PMID:22478568

  10. Propagating Resource Constraints Using Mutual Exclusion Reasoning

    NASA Technical Reports Server (NTRS)

    Frank, Jeremy; Sanchez, Romeo; Do, Minh B.; Clancy, Daniel (Technical Monitor)

    2001-01-01

    One of the most recent techniques for propagating resource constraints in Constraint Based scheduling is Energy Constraint. This technique focuses in precedence based scheduling, where precedence relations are taken into account rather than the absolute position of activities. Although, this particular technique proved to be efficient on discrete unary resources, it provides only loose bounds for jobs using discrete multi-capacity resources. In this paper we show how mutual exclusion reasoning can be used to propagate time bounds for activities using discrete resources. We show that our technique based on critical path analysis and mutex reasoning is just as effective on unary resources, and also shows that it is more effective on multi-capacity resources, through both examples and empirical study.

  11. The roles of tolerance in the evolution, maintenance and breakdown of mutualism

    NASA Astrophysics Data System (ADS)

    Edwards, David P.

    2009-10-01

    Tolerance strategies are cost-reduction mechanisms that enable organisms to recover some of the fitness lost to damage, but impose limited or no cost on antagonists. They are frequently invoked in studies of plant-herbivore and of host-parasite interactions, but the possible roles of tolerance in mutualism (interspecific cooperation) have yet to be thoroughly examined. This review identifies candidate roles for tolerance in the evolution, maintenance and breakdown of mutualism. Firstly, by reducing the cost of damage, tolerance provides a key pathway by which pre-mutualistic hosts can reduce the cost of association with their parasites, promoting cooperation. This holds for the evolution of ‘evolved dependency’ type mutualism, where a host requires an antagonist that does not direct any reward to their partner for some resource, and of ‘outright mutualism’, where participants directly trade benefits. Secondly, in outright mutualism, tolerance might maintain cooperation by reducing the cost of a persisting negative trait in a symbiotic partner. Finally, the evolution of tolerance might also provide a pathway out of mutualism because the host could evolve a cheaper alternative to continued cooperation with its mutualistic partner, permitting autonomy. A key consequence of tolerance is that it contrasts with partner choice mechanisms that impose large costs on cheats, and I highlight understanding any trade-off between tolerance and partner choice as an important research topic in the evolution of cooperation. I conclude by identifying tolerance as part of a more general phenomenon of co-adaptation in mutualism and parasitism that drives the evolution of the cost/benefit ratio from the interaction.

  12. Trade-offs in an ant-plant-fungus mutualism.

    PubMed

    Orivel, Jérôme; Malé, Pierre-Jean; Lauth, Jérémie; Roux, Olivier; Petitclerc, Frédéric; Dejean, Alain; Leroy, Céline

    2017-03-15

    Species engaged in multiple, simultaneous mutualisms are subject to trade-offs in their mutualistic investment if the traits involved in each interaction are overlapping, which can lead to conflicts and affect the longevity of these associations. We investigate this issue via a tripartite mutualism involving an ant plant, two competing ant species and a fungus the ants cultivate to build galleries under the stems of their host plant to capture insect prey. The use of the galleries represents an innovative prey capture strategy compared with the more typical strategy of foraging on leaves. However, because of a limited worker force in their colonies, the prey capture behaviour of the ants results in a trade-off between plant protection (i.e. the ants patrol the foliage and attack intruders including herbivores) and ambushing prey in the galleries, which has a cascading effect on the fitness of all of the partners. The quantification of partners' traits and effects showed that the two ant species differed in their mutualistic investment. Less investment in the galleries (i.e. in fungal cultivation) translated into more benefits for the plant in terms of less herbivory and higher growth rates and vice versa. However, the greater vegetative growth of the plants did not produce a positive fitness effect for the better mutualistic ant species in terms of colony size and production of sexuals nor was the mutualist compensated by the wider dispersal of its queens. As a consequence, although the better ant mutualist is the one that provides more benefits to its host plant, its lower host-plant exploitation does not give this ant species a competitive advantage. The local coexistence of the ant species is thus fleeting and should eventually lead to the exclusion of the less competitive species.

  13. MIDER: Network Inference with Mutual Information Distance and Entropy Reduction

    PubMed Central

    Villaverde, Alejandro F.; Ross, John; Morán, Federico; Banga, Julio R.

    2014-01-01

    The prediction of links among variables from a given dataset is a task referred to as network inference or reverse engineering. It is an open problem in bioinformatics and systems biology, as well as in other areas of science. Information theory, which uses concepts such as mutual information, provides a rigorous framework for addressing it. While a number of information-theoretic methods are already available, most of them focus on a particular type of problem, introducing assumptions that limit their generality. Furthermore, many of these methods lack a publicly available implementation. Here we present MIDER, a method for inferring network structures with information theoretic concepts. It consists of two steps: first, it provides a representation of the network in which the distance among nodes indicates their statistical closeness. Second, it refines the prediction of the existing links to distinguish between direct and indirect interactions and to assign directionality. The method accepts as input time-series data related to some quantitative features of the network nodes (such as e.g. concentrations, if the nodes are chemical species). It takes into account time delays between variables, and allows choosing among several definitions and normalizations of mutual information. It is general purpose: it may be applied to any type of network, cellular or otherwise. A Matlab implementation including source code and data is freely available (http://www.iim.csic.es/~gingproc/mider.html). The performance of MIDER has been evaluated on seven different benchmark problems that cover the main types of cellular networks, including metabolic, gene regulatory, and signaling. Comparisons with state of the art information–theoretic methods have demonstrated the competitive performance of MIDER, as well as its versatility. Its use does not demand any a priori knowledge from the user; the default settings and the adaptive nature of the method provide good results for a wide

  14. On the Mutual Coupling Between Circular Resonant Slots

    NASA Technical Reports Server (NTRS)

    Abou-Khousa, M. A.; Kharkovsky, S.; Zoughi, R.

    2007-01-01

    For near- and far-field microwave imaging purposes, array of circular resonant slots can be utilized to sample the electric field at a given reference plane. In general, the sensitivity of such array probes is impaired by the mutual coupling present between the radiating elements. The mutual coupling problem poses a design tradeoff between the resolution of the array and its sensitivity. In this paper, we investigate the mutual coupling between circular resonant slots in conducting ground plane both numerically and experimentally. Based on the analysis of the dominant coupling mechanism, i.e., the surface currents, various remedies to reduce the slots' mutual coupling are proposed and verified.

  15. On the Mutual Coupling between Circular Resonant Slots

    NASA Technical Reports Server (NTRS)

    Abou-Khousa, M. A.; Kharkovshy, S.; Zoughi, R.

    2007-01-01

    For near- and far-field microwave imaging purposes, array of circular resonant slots can be utilized to sample the electric field at a given reference plane. In general, the sensitivity of such an array is impaired by the existing mutual coupling between the radiating elements or in this case circular slots. The mutual coupling problem imposes a design tradeoff between the resolution of the array and the overall system sensitivity and dynamic range. In this paper, the mutual coupling between circular resonant slots in conducting ground plane is investigated both numerically and experimentally. In particular, the mutual coupling in the E- and H-plane configurations of two identical slots is studied.

  16. In vivo analysis of NH4+ transport and central N-metabolism of Saccharomyces cerevisiae under aerobic N-limited conditions.

    PubMed

    Cueto-Rojas, H F; Maleki Seifar, R; Ten Pierick, A; van Helmond, W; Pieterse M, M; Heijnen, J J; Wahl, S A

    2016-09-16

    Ammonium is the most common N-source for yeast fermentations. Although, its transport and assimilation mechanisms are well documented, there have been only few attempts to measure the in vivo intracellular concentration of ammonium and assess its impact on gene expression. Using an isotope dilution mass spectrometry (IDMS)-based method we were able to measure the intracellular ammonium concentration in N-limited aerobic chemostat cultivations using three different N-sources (ammonium, urea and glutamate) at the same growth rate (0.05 h(-1)). The experimental results suggest that, at this growth rate, a similar concentration of intracellular ammonium, about 3.6 mmol NH4(+)/LIC, is required to supply the reactions in the central N-metabolism independent of the N-source. Based on the experimental results and different assumptions, the vacuolar and cytosolic ammonium concentrations were estimated. Furthermore, we identified a futile cycle caused by NH3 leakage to the extracellular space, which can cost up to 30% of the ATP production of the cell under N-limited conditions, and a futile redox cycle between reactions Gdh1 and Gdh2. Finally, using shotgun proteomics with labeled reference-relative protein expression, differences between the various environmental conditions were identified and correlated with previously identified N-compound sensing mechanisms.

  17. Characterization of the Proteomic Profiles of the Brown Tide Alga Aureoumbra lagunensis under Phosphate- and Nitrogen-Limiting Conditions and of Its Phosphate Limitation-Specific Protein with Alkaline Phosphatase Activity

    PubMed Central

    Sun, Ming-Ming; Sun, Jin; Qiu, Jian-Wen; Jing, Hongmei

    2012-01-01

    The persistent bloom of the brown tide alga Aureoumbra lagunensis has been reported in coastal embayments along southern Texas, but the molecular mechanisms that sustain such algal bloom are unknown. We compared the proteome and physiological parameters of A. lagunensis grown in phosphate (P)-depleted, P- and nitrogen (N)-depleted, and nutrient-replete cultures. For the proteomic analysis, samples from three conditions were subjected to two-dimensional electrophoresis and tandem mass spectrometry analysis. Because of the paucity of genomic resources in this species, a de novo cross-species protein search was used to identify the differentially expressed proteins, which revealed their involvement in several key biological processes, such as chlorophyll synthesis, antioxidative protection, and protein degradation, suggesting that A. lagunensis may adopt intracellular nutrient compensation, extracellular organic nutrient regeneration, and damage protection to thrive in P-depleted environments. A highly abundant P limitation-specific protein, tentatively identified as a putative alkaline phosphatase, was further characterized by enzyme activity assay on nondenaturing gel and confocal microscopy, which confirmed that this protein has alkaline phosphatase activity, is a cytoplasmic protein, and is closely associated with the cell membrane. The abundance, location, and functional expression of this alkaline phosphatase all indicate the importance of organic P utilization for A. lagunensis under P limitation and the possible role of this alkaline phosphatase in regenerating phosphate from extra- or intracellular organic phosphorus. PMID:22247172

  18. Dissipation kinetics and pre-harvest residue limit of pyriofenone in oriental melon (Cucumis melo Var. makuwa) grown under regulated climatic conditions.

    PubMed

    Chung, Hyung Suk; Kabir, Md Humayun; Abd El-Aty, A M; Lee, Han Sol; Rahman, Md Musfiqur; Chang, Byung-Joon; Shin, Ho-Chul; Shim, Jae-Han

    2017-02-23

    A high-performance liquid chromatography-ultraviolet detection was used to estimate the disappearance rates as well as the pre-harvest residue limits of pyriofenone in oriental melon (Cucumis melo var. makuwa) grown under greenhouse conditions in two different locations (A and B) in Seongju, Republic of Korea. The identity of the compound in standard solution and representative field incurred samples was confirmed using liquid chromatography-tandem mass spectrometry. The method was validated in terms of linearity, limits of detection and quantification, accuracy (expressed as recovery) and precision (expressed as relative standard deviation) for accurate and precise quantitation. Notably, the residual levels of field incurred samples collected over days 0-10 post-application were below the maximum residue level (0.2 mg/kg) established by the Korean Ministry of Food and Drug Safety. Site A showed lower residue levels and a higher decline rate than site B, which might be attributed to seasonal variation (high temperature) and increased metabolic and enzyme profiling in the mature fruits. The half-lives were similar, 4.9 and 4.3 days, at sites A and B, respectively. Using the pre-harvest residue limit, we predicted the residue amounts at 10 and 5 days before harvest, which resulted in concentrations lower than the provisional maximum residue level at harvest time.

  19. Phycobilisome-Deficient Strains of Synechocystis sp. PCC 6803 Have Reduced Size and Require Carbon-Limiting Conditions to Exhibit Enhanced Productivity1[W][OPEN

    PubMed Central

    Lea-Smith, David J.; Bombelli, Paolo; Dennis, John S.; Scott, Stuart A.; Smith, Alison G.; Howe, Christopher J.

    2014-01-01

    Reducing excessive light harvesting in photosynthetic organisms may increase biomass yields by limiting photoinhibition and increasing light penetration in dense cultures. The cyanobacterium Synechocystis sp. PCC 6803 harvests light via the phycobilisome, which consists of an allophycocyanin core and six radiating rods, each with three phycocyanin (PC) discs. Via targeted gene disruption and alterations to the promoter region, three mutants with two (pcpcT→C) and one (ΔCpcC1C2:pcpcT→C) PC discs per rod or lacking PC (olive) were generated. Photoinhibition and chlorophyll levels decreased upon phycobilisome reduction, although greater penetration of white light was observed only in the PC-deficient mutant. In all strains cultured at high cell densities, most light was absorbed by the first 2 cm of the culture. Photosynthesis and respiration rates were also reduced in the ΔCpcC1C2:pcpcT→C and olive mutants. Cell size was smaller in the pcpcT→C and olive strains. Growth and biomass accumulation were similar between the wild-type and pcpcT→C under a variety of conditions. Growth and biomass accumulation of the olive mutant were poorer in carbon-saturated cultures but improved in carbon-limited cultures at higher light intensities, as they did in the ΔCpcC1C2:pcpcT→C mutant. This study shows that one PC disc per rod is sufficient for maximal light harvesting and biomass accumulation, except under conditions of high light and carbon limitation, and two or more are sufficient for maximal oxygen evolution. To our knowledge, this study is the first to measure light penetration in bulk cultures of cyanobacteria and offers important insights into photobioreactor design. PMID:24760817

  20. Mutual inhibition of RecQ molecules in DNA unwinding.

    PubMed

    Pan, Bing-Yi; Dou, Shuo-Xing; Yang, Ye; Xu, Ya-Nan; Bugnard, Elisabeth; Ding, Xiu-Yan; Zhang, Lingyun; Wang, Peng-Ye; Li, Ming; Xi, Xu Guang

    2010-05-21

    Helicases make conformational changes and mechanical movements through hydrolysis of NTP to unwind duplex DNA (or RNA). Most helicases require a single-stranded overhang for loading onto the duplex DNA substrates. Some helicases have been observed to exhibit an enhanced unwinding efficiency with increasing length of the single-stranded DNA tail both by preventing reannealing of the unwound DNA and by compensating for premature dissociation of the leading monomers. Here we report a previously unknown mutual inhibition of neighboring monomers in DNA unwinding by the monomeric Escherichia coli RecQ helicase. With single molecule fluorescence resonance energy transfer microscopy, we observed that the unwinding initiation of RecQ at saturating concentrations was more delayed for a long rather than a short tailed DNA. In stopped-flow kinetic studies under both single and multiple turnover conditions, the unwinding efficiency decreased with increasing enzyme concentration for long tailed substrates. In addition, preincubation of RecQ and DNA in the presence of 5'-adenylyl-beta,gamma-imidodiphosphate was observed to alleviate the inhibition. We propose that the mutual inhibition effect results from a forced closure of cleft between the two RecA-like domains of a leading monomer by a trailing one, hence the forward movements of both monomers are stalled by prohibition of ATP binding to the leading one. This effect represents direct evidence for the relative movements of the two RecA-like domains of RecQ in DNA unwinding. It may occur for all superfamily I and II helicases possessing two RecA-like domains.

  1. Controls on dissolved organic matter (DOM) degradation in a headwater stream: the influence of photochemical and hydrological conditions in determining light-limitation or substrate-limitation of photo-degradation

    NASA Astrophysics Data System (ADS)

    Cory, R. M.; Harrold, K. H.; Neilson, B. T.; Kling, G. W.

    2015-07-01

    -degradation is "light-limited" or "substrate-limited". We suggest that degradation, and thus export, of DOM in CDOM-rich streams or ponds similar to Imnavait is typically light-limited under most flow conditions.

  2. Pyruvate dehydrogenase complex regulator (PdhR) gene deletion boosts glucose metabolism in Escherichia coli under oxygen-limited culture conditions.

    PubMed

    Maeda, Soya; Shimizu, Kumiko; Kihira, Chie; Iwabu, Yuki; Kato, Ryuichi; Sugimoto, Makoto; Fukiya, Satoru; Wada, Masaru; Yokota, Atsushi

    2017-04-01

    Pyruvate dehydrogenase complex regulator (PdhR) is a transcriptional regulator that negatively regulates formation of pyruvate dehydrogenase complex (PDHc), NADH dehydrogenase (NDH)-2, and cytochrome bo3 oxidase in Escherichia coli. To investigate the effects of a PdhR defect on glucose metabolism, a pdhR deletion mutant was derived from the wild-type E. coli W1485 strain by λ Red-mediated recombination. While no difference in the fermentation profiles was observed between the two strains under oxygen-sufficient conditions, under oxygen-limited conditions, the growth level of the wild-type strain was significantly decreased with retarded glucose consumption accompanied by by-production of substantial amounts of pyruvic acid and acetic acid. In contrast, the mutant grew and consumed glucose more efficiently than did the wild-type strain with enhanced respiration, little by-production of pyruvic acid, less production yield and rates of acetic acid, thus displaying robust metabolic activity. As expected, increased activities of PDHc and NDH-2 were observed in the mutant. The increased activity of PDHc may explain the loss of pyruvic acid by-production, probably leading to decreased acetic acid formation, and the increased activity of NDH-2 may explain the enhanced respiration. Measurement of the intracellular NAD(+)/NADH ratio in the mutant revealed more oxidative or more reductive intracellular environments than those in the wild-type strain under oxygen-sufficient and -limited conditions, respectively, suggesting another role of PdhR: maintaining redox balance in E. coli. The overall results demonstrate the biotechnological advantages of pdhR deletion in boosting glucose metabolism and also improve our understanding of the role of PdhR in bacterial physiology.

  3. End-point limiting-dilution real-time PCR assay for evaluation of hepatitis C virus quasispecies in serum: performance under optimal and suboptimal conditions.

    PubMed

    Ramachandran, Sumathi; Xia, Guo-Liang; Ganova-Raeva, Lilia M; Nainan, Omana V; Khudyakov, Yury

    2008-08-01

    An approach for determination of hepatitis C virus (HCV) quasispecies by end-point limiting-dilution real-time PCR (EPLD-PCR) is described. It involves isolation of individual coexisting sequence variants of the hypervariable region 1 (HVR1) of the HCV genome from serum specimens using a limiting-dilution protocol. EPLD-PCR applied to an HCV outbreak study provided insights into the epidemiological relationships between incident and chronic cases. When applied to samples from a longitudinal study of infected patients, HVR1 sequences from each sampling time-point were observed to group as distinct phylogenetic clusters. Melting peak analysis conducted on EPLD-PCR products generated from these patients could be used for evaluation of HVR1 sequence heterogeneity without recourse to clonal sequencing. Further, to better understand the mechanism of single-molecule PCR, experiments were conducted under optimal and suboptimal annealing temperatures. Under all temperature conditions tested, HVR1 variants from the major phylogenetic clusters of quasispecies could be amplified, revealing that successful HVR1 quasispecies analysis is not contingent to dilution of starting cDNA preparations to a single-molecule state. It was found that EPLD-PCR conducted at suboptimal annealing temperatures generated distributions of unique-sequence variants slightly different from the distribution obtained by PCR conducted at the optimal temperature. Hence, EPLD-PCR conditions can be manipulated to access different subpopulations of HCV HVR1 quasispecies, thus, improving the range of the quasispecies detection. Although EPLD-PCR conducted at different conditions detect slightly different quasispecies populations, as was shown in this study, the resulted samples of quasispecies are completely suitable for molecular epidemiological investigation in different clinical and epidemiological settings.

  4. Ungulate saliva inhibits a grass-endophyte mutualism.

    PubMed

    Tanentzap, Andrew J; Vicari, Mark; Bazely, Dawn R

    2014-07-01

    Fungal endophytes modify plant-herbivore interactions by producing toxic alkaloids that deter herbivory. However, studies have neglected the direct effects herbivores may have on endophytes. Antifungal properties and signalling effectors in herbivore saliva suggest that evolutionary pressures may select for animals that mitigate the effects of endophyte-produced alkaloids. Here, we tested whether saliva of moose (Alces alces) and European reindeer (Rangifer tarandus) reduced hyphal elongation and production of ergot alkaloids by the foliar endophyte Epichloë festucae associated with the globally distributed red fescue Festuca rubra. Both moose and reindeer saliva reduced the growth of isolated endophyte hyphae when compared with a treatment of distilled water. Induction of the highly toxic alkaloid ergovaline was also inhibited in plants from the core of F. rubra's distribution when treated with moose saliva following simulated grazing. In genotypes from the southern limit of the species' distribution, ergovaline was constitutively expressed, as predicted where growth is environmentally limited. Our results now present the first evidence, to our knowledge, that ungulate saliva can combat plant defences produced by a grass-endophyte mutualism.

  5. Higher Education and Foster Grandparent Programs: Exploring Mutual Benefits

    ERIC Educational Resources Information Center

    Peacock, James R.; O'Quin, Jo Ann

    2006-01-01

    The purpose of this article is to highlight ways in which programs within institutions of higher education and Foster Grandparent Programs can interact to their mutual benefit. Given federal and state initiatives to develop linkages between institutions of higher education and community service sites, mutual benefits exist at the program level for…

  6. 76 FR 20459 - Mutual to Stock Conversion Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-12

    ... Office of Thrift Supervision Mutual to Stock Conversion Application AGENCY: Office of Thrift Supervision... collection. Title of Proposal: Mutual to Stock Conversion Application. OMB Number: 1550-0014. Form Numbers... furnished in the application in order to determine the safety and soundness of the proposed stock...

  7. 76 FR 35084 - Mutual to Stock Conversion Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-15

    ... Office of Thrift Supervision Mutual to Stock Conversion Application AGENCY: Office of Thrift Supervision... following information collection. Title of Proposal: Mutual to Stock Conversion Application. OMB Number... proposed stock conversion. The purpose of the information collection is to provide OTS with the...

  8. 47 CFR 90.165 - Procedures for mutually exclusive applications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Applications and Authorizations Special Rules... exclusive applications. Mutually exclusive commercial mobile radio service applications are processed in... 47 Telecommunication 5 2011-10-01 2011-10-01 false Procedures for mutually exclusive...

  9. 47 CFR 22.131 - Procedures for mutually exclusive applications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES PUBLIC MOBILE SERVICES Licensing Requirements and Procedures Applications and Notifications § 22... procedures in this section for processing mutually exclusive applications in the Public Mobile Services... 47 Telecommunication 2 2010-10-01 2010-10-01 false Procedures for mutually exclusive...

  10. Mutuality, Self-Silencing, and Disordered Eating in College Women

    ERIC Educational Resources Information Center

    Wechsler, Lisa S.; Riggs, Shelley A.; Stabb, Sally D.; Marshall, David M.

    2006-01-01

    The current study examined patterns of association among mutuality, self-silencing, and disordered eating in an ethnically diverse sample of college women (N = 149). Partner mutuality and overall self-silencing were negatively correlated and together were associated with six disordered eating indices. All four self-silencing subscales were…

  11. 7 CFR 550.13 - Mutuality of interest.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Mutuality of interest. 550.13 Section 550.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT.... Mutual interest exists when both parties benefit in the same qualitative way from the objectives of...

  12. 7 CFR 550.13 - Mutuality of interest.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Mutuality of interest. 550.13 Section 550.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT.... Mutual interest exists when both parties benefit in the same qualitative way from the objectives of...

  13. 7 CFR 550.13 - Mutuality of interest.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Mutuality of interest. 550.13 Section 550.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT.... Mutual interest exists when both parties benefit in the same qualitative way from the objectives of...

  14. 7 CFR 550.13 - Mutuality of interest.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Mutuality of interest. 550.13 Section 550.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT.... Mutual interest exists when both parties benefit in the same qualitative way from the objectives of...

  15. 7 CFR 550.13 - Mutuality of interest.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Mutuality of interest. 550.13 Section 550.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT.... Mutual interest exists when both parties benefit in the same qualitative way from the objectives of...

  16. 47 CFR 90.165 - Procedures for mutually exclusive applications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Procedures for mutually exclusive applications... filing dates) as acceptable for filing. (4) Window filing group. A window filing group comprises mutually exclusive applications whose filing date is within an announced filing window. An announced filing window...

  17. Plant chemical defence: a partner control mechanism stabilising plant - seed-eating pollinator mutualisms

    PubMed Central

    Ibanez, Sébastien; Gallet, Christiane; Dommanget, Fanny; Després, Laurence

    2009-01-01

    Background Mutualisms are inherently conflictual as one partner always benefits from reducing the costs imposed by the other. Despite the widespread recognition that mutualisms are essentially reciprocal exploitation, there are few documented examples of traits that limit the costs of mutualism. In plant/seed-eating pollinator interactions the only mechanisms reported so far are those specific to one particular system, such as the selective abortion of over-exploited fruits. Results This study shows that plant chemical defence against developing larvae constitutes another partner sanction mechanism in nursery mutualisms. It documents the chemical defence used by globeflower Trollius europaeus L. (Ranunculaceae) against the seed-eating larvae of six pollinating species of the genus Chiastocheta Pokorny (Anthomyiidae). The correlative field study carried out shows that the severity of damage caused by Chiastocheta larvae to globeflower fruits is linked to the accumulation in the carpel walls of a C-glycosyl-flavone (adonivernith), which reduces the larval seed predation ability per damaged carpel. The different Chiastocheta species do not exploit the fruit in the same way and their interaction with the plant chemical defence is variable, both in terms of induction intensity and larval sensitivity to adonivernith. Conclusion Adonivernith accumulation and larval predation intensity appear to be both the reciprocal cause and effect. Adonivernith not only constitutes an effective chemical means of partner control, but may also play a key role in the sympatric diversification of the Chiastocheta genus. PMID:19887006

  18. Associations between chronic conditions, body functions, activity limitations and participation restrictions: a cross-sectional approach in Spanish non-clinical populations

    PubMed Central

    Rodríguez-Blázquez, Carmen; Damián, Javier; Andrés-Prado, María José; Almazán-Isla, Javier; Alcalde-Cabero, Enrique; Forjaz, Maria João; Castellote, Juan Manuel; González-Enríquez, Jesús; Martínez-Martín, Pablo; Comín, Magdalena; de Pedro-Cuesta, Jesús

    2016-01-01

    Objectives To analyse the relationships between chronic conditions, body functions, activity limitations and participation restrictions in the International Classification of Functioning, Disability and Health (ICF) framework. Design A cross-sectional study. Setting 2 geographical areas in the Autonomous Region of Aragon, Spain, namely, a rural area, Cinco Villas, and an urban area in the city of Zaragoza. Participants 864 individuals selected by simple random sampling from the register of Social Security card holders, aged 50 years and over, positive to disability screening. Main outcome measures ICF Checklist—body function domains, WHO Disability Assessment Schedule 2.0 (WHODAS 2.0, 36-item (WHODAS-36)) global scores and medical diagnoses (chronic conditions) from primary care records. Results Mild disability (WHODAS-36 level 5–24%) was present in 51.5% of the sample. In the adjusted ordinal regression model with WHODAS-36 as the dependent variable, disability was substantially associated with moderate-to-complete impairment in the following functions: mental, OR 212.8 (95% CI 72 to 628.9); neuromusculoskeletal, OR 44.8 (24.2 to 82.8); and sensory and pain, OR 6.3 (3.5 to 11.2). In the relationship between health conditions and body function impairments, the strongest links were seen for: dementia with mental functions, OR 50.6 (25.1 to 102.1); cerebrovascular disease with neuromusculoskeletal function, OR 5.8 (3.5 to 9.7); and chronic renal failure with sensory function and pain, OR 3.0 (1.49 to 6.4). Dementia, OR 8.1 (4.4 to 14.7) and cerebrovascular disease, OR 4.1 (2.7 to 6.4) were associated with WHODAS-36 scores. Conclusions Body functions are heterogeneously linked to limitations in activities and restrictions on participation, with the highest impact being due to mental and musculoskeletal functions. This may be relevant for disability assessment and intervention design, particularly if defined on a body function basis. Control of specific health

  19. Diversification and coevolution in brood pollination mutualisms: Windows into the role of biotic interactions in generating biological diversity.

    PubMed

    Hembry, David H; Althoff, David M

    2016-10-01

    Brood pollination mutualisms-interactions in which specialized insects are both the pollinators (as adults) and seed predators (as larvae) of their host plants-have been influential study systems for coevolutionary biology. These mutualisms include those between figs and fig wasps, yuccas and yucca moths, leafflowers and leafflower moths, globeflowers and globeflower flies, Silene plants and Hadena and Perizoma moths, saxifrages and Greya moths, and senita cacti and senita moths. The high reciprocal diversity and species-specificity of some of these mutualisms have been cited as evidence that coevolution between plants and pollinators drives their mutual diversification. However, the mechanisms by which these mutualisms diversify have received less attention. In this paper, we review key hypotheses about how these mutualisms diversify and what role coevolution between plants and pollinators may play in this process. We find that most species-rich brood pollination mutualisms show significant phylogenetic congruence at high taxonomic scales, but there is limited evidence for the processes of both cospeciation and duplication, and there are no unambiguous examples known of strict-sense contemporaneous cospeciation. Allopatric speciation appears important across multiple systems, particularly in the insects. Host-shifts appear to be common, and widespread host-shifts by pollinators may displace other pollinator lineages. There is relatively little evidence for a "coevolution through cospeciation" model or that coevolution promotes speciation in these systems. Although we have made great progress in understanding the mechanisms by which brood pollination mutualisms diversify, many opportunities remain to use these intriguing symbioses to understand the role of biotic interactions in generating biological diversity.

  20. Economic game theory for mutualism and cooperation.

    PubMed

    Archetti, Marco; Scheuring, István; Hoffman, Moshe; Frederickson, Megan E; Pierce, Naomi E; Yu, Douglas W

    2011-12-01

    We review recent work at the interface of economic game theory and evolutionary biology that provides new insights into the evolution of partner choice, host sanctions, partner fidelity feedback and public goods. (1) The theory of games with asymmetrical information shows that the right incentives allow hosts to screen-out parasites and screen-in mutualists, explaining successful partner choice in the absence of signalling. Applications range from ant-plants to microbiomes. (2) Contract theory distinguishes two longstanding but weakly differentiated explanations of host response to defectors: host sanctions and partner fidelity feedback. Host traits that selectively punish misbehaving symbionts are parsimoniously interpreted as pre-adaptations. Yucca-moth and legume-rhizobia mutualisms are argued to be examples of partner fidelity feedback. (3) The theory of public goods shows that cooperation in multi-player interactions can evolve in the absence of assortment, in one-shot social dilemmas among non-kin. Applications include alarm calls in vertebrates and exoenzymes in microbes.

  1. Observation of mutual neutralization in detached plasma

    NASA Astrophysics Data System (ADS)

    Akira, Tonegawa; Isao, Shirota; Ken'ichi, Yoshida; Masataka, Ono; Kazutaka, Kawamura; Tuguhiro, Watanabe; Nobuyoshi, Ohyabu; Hajime, Suzuki; Kazuo, Takayama

    2001-10-01

    Mutual neutralization in collisions between negative ions and positive ions in molecular activated recombination (MAR) has been observed in a high density magnetized sheet plasma source TPDSHEET-IV(Test Plasma produced by Directed current for SHEET plasma) device. Measurements of the negative ion density of hydrogen atom, the electron density, electron temperature, and the heat load to the target plate were carried out in hydrogen high density plasma with hydrogen gas puff. A cylindrical probe made of tungsten ( 0.4 x 2 cm) was used to measure the spatial profiles of H- by a probe-assisted laser photodetachment The Balmer spectra of visible light emission from hydrogen or helium atoms were detected in front of the target plate. A small amount of secondary hydrogen gas puffing into a hydrogen plasma reduced strongly the heat flux to the target and increased rapidly the density of negative ions of hydrogen atom in the circumference of the plasma, while the conventional radiative and three-body recombination processes were disappeared. These results can be well explained by taking the charge exchange recombination of MAR in the detached plasma into account.

  2. Quantum mutual information along unitary orbits

    NASA Astrophysics Data System (ADS)

    Jevtic, Sania; Jennings, David; Rudolph, Terry

    2012-05-01

    Motivated by thermodynamic considerations, we analyze the variation of the quantum mutual information on a unitary orbit of a bipartite system's state with and without global constraints such as energy conservation. We solve the full optimization problem for the smallest system of two qubits and explore thoroughly the effect of unitary operations on the space of reduced-state spectra. We then provide applications of these ideas to physical processes within closed quantum systems such as a generalized collision model approach to thermal equilibrium and a global Maxwell demon playing tricks on local observers. For higher dimensions, the maximization of correlations is relatively straightforward for equal-sized subsystems, however their minimization displays nontrivial structures. We characterize a set of separable states in which the minimally correlated state resides: a collection of classically correlated states admitting a particular “Young tableau” form. Furthermore, a partial order exists on this set with respect to individual marginal entropies, and the presence of a “see-saw effect” for these entropies forces a finer analysis to determine the optimal tableau.

  3. Phosphorus as a driver of nitrogen limitation and sustained eutrophic conditions in Bolinao and Anda, Philippines, a mariculture-impacted tropical coastal area.

    PubMed

    Ferrera, Charissa M; Watanabe, Atsushi; Miyajima, Toshihiro; San Diego-McGlone, Maria Lourdes; Morimoto, Naoko; Umezawa, Yu; Herrera, Eugene; Tsuchiya, Takumi; Yoshikai, Masaya; Nadaoka, Kazuo

    2016-04-15

    The dynamics of nitrogen (N) and phosphorus (P) was studied in mariculture areas around Bolinao and Anda, Philippines to examine its possible link to recurring algal blooms, hypoxia and fish kills. They occur despite regulation on number of fish farm structures in Bolinao to improve water quality after 2002, following a massive fish kill in the area. Based on spatiotemporal surveys, coastal waters remained eutrophic a decade after imposing regulation, primarily due to decomposition of uneaten and undigested feeds, and fish excretions. Relative to Redfield ratio (16), these materials are enriched in P, resulting in low N/P ratios (~6.6) of regenerated nutrients. Dissolved inorganic P (DIP) in the water reached 4μM during the dry season, likely exacerbated by increase in fish farm structures in Anda. DIP enrichment created an N-limited condition that is highly susceptible to sporadic algal blooms whenever N is supplied from freshwater during the wet season.

  4. Microwave-Assisted Superheating and/or Microwave-Specific Superboiling (Nucleation-Limited Boiling) of Liquids Occurs under Certain Conditions but is Mitigated by Stirring.

    PubMed

    Ferrari, Anthony; Hunt, Jacob; Stiegman, Albert; Dudley, Gregory B

    2015-12-04

    Temporary superheating and sustained nucleation-limited "superboiling" of unstirred liquids above the normal atmospheric boiling point have been documented during microwave heating. These phenomena are reliably observed under prescribed conditions, although the duration (of superheating) and magnitude (of superheating and superboiling) vary according to system parameters such as volume of the liquid and the size and shape of the vessel. Both phenomena are mitigated by rapid stirring with an appropriate stir bar and/or with the addition of boiling chips, which provide nucleation sites to support the phase-change from liquid to gas. With proper experimental design and especially proper stirring, the measured temperature of typical organic reaction mixtures heated at reflux will be close to the normal boiling point temperature of the solvent, whether heated using microwave radiation or conventional convective heat transfer. These observations are important to take into consideration when comparing reaction rates under conventional and microwave heating.

  5. Small dispersion limit of the Korteweg-de Vries equation with periodic initial conditions and analytical description of the Zabusky-Kruskal experiment

    NASA Astrophysics Data System (ADS)

    Deng, Guo; Biondini, Gino; Trillo, Stefano

    2016-10-01

    We study the small dispersion limit of the Korteweg-de Vries (KdV) equation with periodic boundary conditions and we apply the results to the Zabusky-Kruskal experiment. In particular, we employ a WKB approximation for the solution of the scattering problem for the KdV equation [i.e., the time-independent Schrödinger equation] to obtain an asymptotic expression for the trace of the monodromy matrix and thereby of the spectrum of the problem. We then perform a detailed analysis of the structure of said spectrum (i.e., band widths, gap widths and relative band widths) as a function of the dispersion smallness parameter ɛ. We then formulate explicit approximations for the number of solitons and corresponding soliton amplitudes as a function of ɛ. Finally, by performing an appropriate rescaling, we compare our results to those in the famous Zabusky and Kruskal's paper, showing very good agreement with the numerical results.

  6. Impact of sea-level rise on cross-shore sediment transport on fetch-limited barrier reef island beaches under modal and cyclonic conditions.

    PubMed

    Baldock, T E; Golshani, A; Atkinson, A; Shimamoto, T; Wu, S; Callaghan, D P; Mumby, P J

    2015-08-15

    A one-dimensional wave model is combined with an analytical sediment transport model to investigate the likely influence of sea-level rise on net cross-shore sediment transport on fetch-limited barrier reef and lagoon island beaches. The modelling considers if changes in the nearshore wave height and wave period in the lagoon induced by different water levels over the reef flat are likely to lead to net offshore or onshore movement of sediment. The results indicate that the effects of SLR on net sediment movement are highly variable and controlled by the bathymetry of the reef and lagoon. A significant range of reef-lagoon bathymetry, and notably shallow and narrow reefs, appears to lead hydrodynamic conditions and beaches that are likely to be stable or even accrete under SLR. Loss of reef structural complexity, particularly on the reef flat, increases the chance of sediment transport away from beaches and offshore.

  7. Functional characterization of the rice UDP-glucose 4-epimerase 1, OsUGE1: a potential role in cell wall carbohydrate partitioning during limiting nitrogen conditions.

    PubMed

    Guevara, David R; El-Kereamy, Ashraf; Yaish, Mahmoud W; Mei-Bi, Yong; Rothstein, Steven J

    2014-01-01

    Plants grown under inadequate mineralized nitrogen (N) levels undergo N and carbon (C) metabolic re-programming which leads to significant changes in both soluble and insoluble carbohydrate profiles. However, relatively little information is available on the genetic factors controlling carbohydrate partitioning during adaptation to N-limitation conditions in plants. A gene encoding a uridine-diphospho-(UDP)-glucose 4-epimerase (OsUGE-1) from rice (Oryza sativa) was found to be N-responsive. We developed transgenic rice plants to constitutively over-express the OsUGE-1 gene (OsUGE1-OX1-2). The transgenic rice lines were similar in size to wild-type plants at the vegetative stage and at maturity regardless of the N-level tested. However, OsUGE1-OX lines maintained 18-24% more sucrose and 12-22% less cellulose in shoots compared to wild-type when subjected to sub-optimal N-levels. Interestingly, OsUGE1-OX lines maintained proportionally more galactose and glucose in the hemicellulosic polysaccharide profile of plants compared to wild-type plants when grown under low N. The altered cell wall C-partitioning during N-limitation in the OsUGE1-OX lines appears to be mediated by OsUGE1 via the repression of the cellulose synthesis associated genes, OsSus1, OsCesA4, 7, and 9. This relationship may implicate a novel control point for the deposition of UDP-glucose to the complex polysaccharide profiles of rice cell walls. However, a direct relationship between OsUGE1 and cell wall C-partitioning during N-limitation requires further investigation.

  8. Functional Characterization of the Rice UDP-glucose 4-epimerase 1, OsUGE1: A Potential Role in Cell Wall Carbohydrate Partitioning during Limiting Nitrogen Conditions

    PubMed Central

    Guevara, David R.; El-Kereamy, Ashraf; Yaish, Mahmoud W.; Mei-Bi, Yong; Rothstein, Steven J.

    2014-01-01

    Plants grown under inadequate mineralized nitrogen (N) levels undergo N and carbon (C) metabolic re-programming which leads to significant changes in both soluble and insoluble carbohydrate profiles. However, relatively little information is available on the genetic factors controlling carbohydrate partitioning during adaptation to N-limitation conditions in plants. A gene encoding a uridine-diphospho-(UDP)-glucose 4-epimerase (OsUGE-1) from rice (Oryza sativa) was found to be N-responsive. We developed transgenic rice plants to constitutively over-express the OsUGE-1 gene (OsUGE1-OX1–2). The transgenic rice lines were similar in size to wild-type plants at the vegetative stage and at maturity regardless of the N-level tested. However, OsUGE1-OX lines maintained 18–24% more sucrose and 12–22% less cellulose in shoots compared to wild-type when subjected to sub-optimal N-levels. Interestingly, OsUGE1-OX lines maintained proportionally more galactose and glucose in the hemicellulosic polysaccharide profile of plants compared to wild-type plants when grown under low N. The altered cell wall C-partitioning during N-limitation in the OsUGE1-OX lines appears to be mediated by OsUGE1 via the repression of the cellulose synthesis associated genes, OsSus1, OsCesA4, 7, and 9. This relationship may implicate a novel control point for the deposition of UDP-glucose to the complex polysaccharide profiles of rice cell walls. However, a direct relationship between OsUGE1 and cell wall C-partitioning during N-limitation requires further investigation. PMID:24788752

  9. Overexpression of Arabidopsis NLP7 improves plant growth under both nitrogen-limiting and -sufficient conditions by enhancing nitrogen and carbon assimilation

    PubMed Central

    Yu, Lin-Hui; Wu, Jie; Tang, Hui; Yuan, Yang; Wang, Shi-Mei; Wang, Yu-Ping; Zhu, Qi-Sheng; Li, Shi-Gui; Xiang, Cheng-Bin

    2016-01-01

    Nitrogen is essential for plant survival and growth. Excessive application of nitrogenous fertilizer has generated serious environment pollution and increased production cost in agriculture. To deal with this problem, tremendous efforts have been invested worldwide to increase the nitrogen use ability of crops. However, only limited success has been achieved to date. Here we report that NLP7 (NIN-LIKE PROTEIN 7) is a potential candidate to improve plant nitrogen use ability. When overexpressed in Arabidopsis, NLP7 increases plant biomass under both nitrogen-poor and -rich conditions with better-developed root system and reduced shoot/root ratio. NLP7–overexpressing plants show a significant increase in key nitrogen metabolites, nitrogen uptake, total nitrogen content, and expression levels of genes involved in nitrogen assimilation and signalling. More importantly, overexpression of NLP7 also enhances photosynthesis rate and carbon assimilation, whereas knockout of NLP7 impaired both nitrogen and carbon assimilation. In addition, NLP7 improves plant growth and nitrogen use in transgenic tobacco (Nicotiana tabacum). Our results demonstrate that NLP7 significantly improves plant growth under both nitrogen-poor and -rich conditions by coordinately enhancing nitrogen and carbon assimilation and sheds light on crop improvement. PMID:27293103

  10. Overexpression of Arabidopsis NLP7 improves plant growth under both nitrogen-limiting and -sufficient conditions by enhancing nitrogen and carbon assimilation.

    PubMed

    Yu, Lin-Hui; Wu, Jie; Tang, Hui; Yuan, Yang; Wang, Shi-Mei; Wang, Yu-Ping; Zhu, Qi-Sheng; Li, Shi-Gui; Xiang, Cheng-Bin

    2016-06-13

    Nitrogen is essential for plant survival and growth. Excessive application of nitrogenous fertilizer has generated serious environment pollution and increased production cost in agriculture. To deal with this problem, tremendous efforts have been invested worldwide to increase the nitrogen use ability of crops. However, only limited success has been achieved to date. Here we report that NLP7 (NIN-LIKE PROTEIN 7) is a potential candidate to improve plant nitrogen use ability. When overexpressed in Arabidopsis, NLP7 increases plant biomass under both nitrogen-poor and -rich conditions with better-developed root system and reduced shoot/root ratio. NLP7-overexpressing plants show a significant increase in key nitrogen metabolites, nitrogen uptake, total nitrogen content, and expression levels of genes involved in nitrogen assimilation and signalling. More importantly, overexpression of NLP7 also enhances photosynthesis rate and carbon assimilation, whereas knockout of NLP7 impaired both nitrogen and carbon assimilation. In addition, NLP7 improves plant growth and nitrogen use in transgenic tobacco (Nicotiana tabacum). Our results demonstrate that NLP7 significantly improves plant growth under both nitrogen-poor and -rich conditions by coordinately enhancing nitrogen and carbon assimilation and sheds light on crop improvement.

  11. Population dynamics and the ecological stability of obligate pollination mutualisms

    USGS Publications Warehouse

    Holland, J. Nathaniel; DeAngelis, Donald L.

    2001-01-01

    Mutualistic interactions almost always produce both costs and benefits for each of the interacting species. It is the difference between gross benefits and costs that determines the net benefit and the per-capita effect on each of the interacting populations. For example, the net benefit of obligate pollinators, such as yucca and senita moths, to plants is determined by the difference between the number of ovules fertilized from moth pollination and the number of ovules eaten by the pollinator's larvae. It is clear that if pollinator populations are large, then, because many eggs are laid, costs to plants are large, whereas, if pollinator populations are small, gross benefits are low due to lack of pollination. Even though the size and dynamics of the pollinator population are likely to be crucial, their importance has been neglected in the investigation of mechanisms, such as selective fruit abortion, that can limit costs and increase net benefits. Here, we suggest that both the population size and dynamics of pollinators are important in determining the net benefits to plants, and that fruit abortion can significantly affect these. We develop a model of mutualism between populations of plants and their pollinating seed-predators to explore the ecological consequences of fruit abortion on pollinator population dynamics and the net effect on plants. We demonstrate that the benefit to a plant population is unimodal as a function of pollinator abundance, relative to the abundance of flowers. Both selective abortion of fruit with eggs and random abortion of fruit, without reference to whether they have eggs or not, can limit pollinator population size. This can increase the net benefits to the plant population by limiting the number of eggs laid, if the pollination rate remains high. However, fruit abortion can possibly destabilize the pollinator population, with negative consequences for the plant population.

  12. Mutual Information Between GPS Measurements and Earthquakes

    NASA Astrophysics Data System (ADS)

    Wang, T.; Bebbington, M. S.

    2009-12-01

    Prior to the wide deployment of Continuous GPS stations in the early 1990s, there were a number of well-documented deformation rate changes observed before large earthquakes. GPS measurements provide the opportunity for systematic investigation of pre-, co- and post-seismic deformation anomalies, but contain much noise that needs to be filtered out of the observations. Assuming the existence of an earthquake cycle (for example, mainshock--aftershock--quiescence--precursory seismicity), a hidden Markov model (HMM) provides a natural framework for analyzing the observed GPS data. For two case studies of a) deep earthquakes in the central North Island, New Zealand, and b) shallow earthquakes in Southern California, an HMM fitted to the trend ranges of the GPS measurements can classify the deformation data into different patterns which form proxies for states of the earthquake cycle. Mutual information can be used to examine whether there is any relation between these patterns, in particular the Viterbi path, and subsequent (or previous) earthquakes. One class of GPS movements (identified by the HMM as having the largest range of deformation rate changes) appears to have some precursory character for earthquakes with minimum magnitude 5.1 (central North Island, New Zealand, 26 earthquakes in 1747 days) and 4.5 (Southern California, 50 earthquakes in 3815 days). We define a ``Time of Increased Probability'' (TIP) as being a 10-day interval (central North Island, New Zealand) or a 20-day interval (Southern California) following entry (as identified by the Viterbi algorithm) to the `precursory' hidden state, and examine the performance of this in probabilistically forecasting subsequent earthquakes.

  13. Mutual best friendship involvement, best friends' rejection sensitivity, and psychological maladaptation.

    PubMed

    Bowker, Julie C; Thomas, Katelyn K; Norman, Kelly E; Spencer, Sarah V

    2011-05-01

    Rejection sensitivity (RS) refers to the tendency to anxiously expect, readily perceive, and overreact to experiences of possible rejection. RS is a clear risk factor for psychological maladaptation during early adolescence. However, there is growing evidence of significant heterogeneity in the psychological correlates of RS. To investigate when RS poses the greatest psychological risk during early adolescence, this study examines mutual best friendship involvement (or lack thereof) and the best friends' RS as potential moderators of the associations between RS and psychological difficulties. Participants were 150 7th grade students (58 boys; M age = 13.05 years) who nominated their best friends, and reported on their RS, social anxiety, and self-esteem. Results from a series of hierarchical multiple regression analyses indicated that mutual best friendship involvement and best friends' RS were both significant moderators when fear of negative evaluation (a type of social anxiety) served as the dependent variable. The association between RS and fear of negative evaluation was stronger for adolescents without mutual best friends than adolescents with mutual best friends. In addition, the association between RS and fear of negative evaluation was the strongest for adolescents whose best friends were highly rejection sensitive (relative to adolescents whose best friends were moderately or low in RS). Findings highlight the importance of considering best friendships in studies of RS and strongly suggest that, although having mutual best friendships may be protective for rejection sensitive adolescents, having a rejection sensitive best friend may exacerbate difficulties. The significance of friends in the lives of rejection sensitive adolescents is discussed as well as possible applied implications of the findings and study limitations.

  14. Phase-locked laser array through global antenna mutual coupling

    SciTech Connect

    Kao, Tsung -Yu; Reno, John L.; Hu, Qing

    2016-01-01

    Here, phase locking of an array of lasers is a highly effective way in beam shaping, to increase the output power, and to reduce lasing threshold. In this work, we present a novel phase-locking mechanism based on "antenna mutual coupling" wherein laser elements interact through far-field radiations with definite phase relations. This allows long-range global coupling among array elements to achieve robust 2-dimensional phase-locked laser array. The new scheme is ideal for lasers with deep sub-wavelength confined cavity such as nanolasers, where the divergent beam pattern could be used to form strong coupling among elements in the array. We experimentally demonstrated such a scheme using sub-wavelength short-cavity surface-emitting lasers at terahertz frequency. More than 37 laser elements are phase-locked to each other, delivering up to 6.5 mW single-mode radiations at ~3 terahertz, with maximum 450-mW/A slope efficiency and near diffraction limit beam divergence.

  15. Phase-locked laser array through global antenna mutual coupling

    DOE PAGES

    Kao, Tsung -Yu; Reno, John L.; Hu, Qing

    2016-01-01

    Here, phase locking of an array of lasers is a highly effective way in beam shaping, to increase the output power, and to reduce lasing threshold. In this work, we present a novel phase-locking mechanism based on "antenna mutual coupling" wherein laser elements interact through far-field radiations with definite phase relations. This allows long-range global coupling among array elements to achieve robust 2-dimensional phase-locked laser array. The new scheme is ideal for lasers with deep sub-wavelength confined cavity such as nanolasers, where the divergent beam pattern could be used to form strong coupling among elements in the array. We experimentallymore » demonstrated such a scheme using sub-wavelength short-cavity surface-emitting lasers at terahertz frequency. More than 37 laser elements are phase-locked to each other, delivering up to 6.5 mW single-mode radiations at ~3 terahertz, with maximum 450-mW/A slope efficiency and near diffraction limit beam divergence.« less

  16. A syndrome of mutualism reinforces the lifestyle of a sloth

    PubMed Central

    Pauli, Jonathan N.; Mendoza, Jorge E.; Steffan, Shawn A.; Carey, Cayelan C.; Weimer, Paul J.; Peery, M. Zachariah

    2014-01-01

    Arboreal herbivory is rare among mammals. The few species with this lifestyle possess unique adaptions to overcome size-related constraints on nutritional energetics. Sloths are folivores that spend most of their time resting or eating in the forest canopy. A three-toed sloth will, however, descend its tree weekly to defecate, which is risky, energetically costly and, until now, inexplicable. We hypothesized that this behaviour sustains an ecosystem in the fur of sloths, which confers cryptic nutritional benefits to sloths. We found that the more specialized three-toed sloths harboured more phoretic moths, greater concentrations of inorganic nitrogen and higher algal biomass than the generalist two-toed sloths. Moth density was positively related to inorganic nitrogen concentration and algal biomass in the fur. We discovered that sloths consumed algae from their fur, which was highly digestible and lipid-rich. By descending a tree to defecate, sloths transport moths to their oviposition sites in sloth dung, which facilitates moth colonization of sloth fur. Moths are portals for nutrients, increasing nitrogen levels in sloth fur, which fuels algal growth. Sloths consume these algae-gardens, presumably to augment their limited diet. These linked mutualisms between moths, sloths and algae appear to aid the sloth in overcoming a highly constrained lifestyle. PMID:24452028

  17. Aggressive mimicry coexists with mutualism in an aphid

    PubMed Central

    Salazar, Adrián; Fürstenau, Benjamin; Quero, Carmen; Pérez-Hidalgo, Nicolás; Carazo, Pau; Font, Enrique; Martínez-Torres, David

    2015-01-01

    Understanding the evolutionary transition from interspecific exploitation to cooperation is a major challenge in evolutionary biology. Ant–aphid relationships represent an ideal system to this end because they encompass a coevolutionary continuum of interactions ranging from mutualism to antagonism. In this study, we report an unprecedented interaction along this continuum: aggressive mimicry in aphids. We show that two morphs clonally produced by the aphid Paracletus cimiciformis during its root-dwelling phase establish relationships with ants at opposite sides of the mutualism–antagonism continuum. Although one of these morphs exhibits the conventional trophobiotic (mutualistic) relationship with ants of the genus Tetramorium, aphids of the alternative morph are transported by the ants to their brood chamber and cared for as if they were true ant larvae. Gas chromatography-mass spectrometry analyses reveal that the innate cuticular hydrocarbon profile of the mimic morph resembles the profile of ant larvae more than that of the alternative, genetically identical nonmimic morph. Furthermore, we show that, once in the brood chamber, mimic aphids suck on ant larva hemolymph. These results not only add aphids to the limited list of arthropods known to biosynthesize the cuticular chemicals of their deceived hosts to exploit their resources but describe a remarkable case of plastic aggressive mimicry. The present work adds a previously unidentified dimension to the classical textbook paradigm of aphid–ant relationships by showcasing a complex system at the evolutionary interface between cooperation and exploitation. PMID:25583474

  18. A syndrome of mutualism reinforces the lifestyle of a sloth.

    PubMed

    Pauli, Jonathan N; Mendoza, Jorge E; Steffan, Shawn A; Carey, Cayelan C; Weimer, Paul J; Peery, M Zachariah

    2014-03-07

    Arboreal herbivory is rare among mammals. The few species with this lifestyle possess unique adaptions to overcome size-related constraints on nutritional energetics. Sloths are folivores that spend most of their time resting or eating in the forest canopy. A three-toed sloth will, however, descend its tree weekly to defecate, which is risky, energetically costly and, until now, inexplicable. We hypothesized that this behaviour sustains an ecosystem in the fur of sloths, which confers cryptic nutritional benefits to sloths. We found that the more specialized three-toed sloths harboured more phoretic moths, greater concentrations of inorganic nitrogen and higher algal biomass than the generalist two-toed sloths. Moth density was positively related to inorganic nitrogen concentration and algal biomass in the fur. We discovered that sloths consumed algae from their fur, which was highly digestible and lipid-rich. By descending a tree to defecate, sloths transport moths to their oviposition sites in sloth dung, which facilitates moth colonization of sloth fur. Moths are portals for nutrients, increasing nitrogen levels in sloth fur, which fuels algal growth. Sloths consume these algae-gardens, presumably to augment their limited diet. These linked mutualisms between moths, sloths and algae appear to aid the sloth in overcoming a highly constrained lifestyle.

  19. Spatial Mutual Information Based Hyperspectral Band Selection for Classification

    PubMed Central

    2015-01-01

    The amount of information involved in hyperspectral imaging is large. Hyperspectral band selection is a popular method for reducing dimensionality. Several information based measures such as mutual information have been proposed to reduce information redundancy among spectral bands. Unfortunately, mutual information does not take into account the spatial dependency between adjacent pixels in images thus reducing its robustness as a similarity measure. In this paper, we propose a new band selection method based on spatial mutual information. As validation criteria, a supervised classification method using support vector machine (SVM) is used. Experimental results of the classification of hyperspectral datasets show that the proposed method can achieve more accurate results. PMID:25918742

  20. A deficiency in the flavoprotein of Arabidopsis mitochondrial complex II results in elevated photosynthesis and better growth in nitrogen-limiting conditions.

    PubMed

    Fuentes, Daniela; Meneses, Marco; Nunes-Nesi, Adriano; Araújo, Wagner L; Tapia, Rodrigo; Gómez, Isabel; Holuigue, Loreto; Gutiérrez, Rodrigo A; Fernie, Alisdair R; Jordana, Xavier

    2011-11-01

    Mitochondrial complex II (succinate dehydrogenase [SDH]) plays roles both in the tricarboxylic acid cycle and the respiratory electron transport chain. In Arabidopsis (Arabidopsis thaliana), its flavoprotein subunit is encoded by two nuclear genes, SDH1-1 and SDH1-2. Here, we characterize heterozygous SDH1-1/sdh1-1 mutant plants displaying a 30% reduction in SDH activity as well as partially silenced plants obtained by RNA interference. We found that these plants displayed significantly higher CO(2) assimilation rates and enhanced growth than wild-type plants. There was a strong correlation between CO(2) assimilation and stomatal conductance, and both mutant and silenced plants displayed increased stomatal aperture and density. By contrast, no significant differences were found for dark respiration, chloroplastic electron transport rate, CO(2) uptake at saturating concentrations of CO(2), or biochemical parameters such as the maximum rates of carboxylation by Rubisco and of photosynthetic electron transport. Thus, photosynthesis is enhanced in SDH-deficient plants by a mechanism involving a specific effect on stomatal function that results in improved CO(2) uptake. Metabolic and transcript profiling revealed that mild deficiency in SDH results in limited effects on metabolism and gene expression, and data suggest that decreases observed in the levels of some amino acids were due to a higher flux to proteins and other nitrogen-containing compounds to support increased growth. Strikingly, SDH1-1/sdh1-1 seedlings grew considerably better in nitrogen-limiting conditions. Thus, a subtle metabolic alteration may lead to changes in important functions such as stomatal function and nitrogen assimilation.

  1. Dissolution of unirradiated UO{sub 2} fuel under oxidizing conditions: Evaluation of solubility (steady state) limiting factors (EQ3/6)

    SciTech Connect

    Ollila, K.

    1997-12-31

    The solubility behavior of unirradiated UO{sub 2} pellets was studied under oxic, air-saturated conditions in deionized water, in NaHCO{sub 3} solutions and in two types of synthetic groundwater (25 C). The Allard groundwater represents natural fresh groundwater conditions at great depths in granite bedrock and bentonite groundwater simulates the effects of bentonite on granitic fresh groundwater. The release of uranium was measured during static batch dissolution experiments of long duration (6 years). A comparison was made with the theoretical solubility data calculated with the geochemical code, EQ3/6, in order to evaluate solubility (steady state) limiting factors. Various hypotheses for redox control (redox potential of the bulk solution or redox potential at the surface) were tested in the modeling of calculations. The measured concentrations for uranium at steady-state in deionized water were equal to the solubility of schoepite (pO{sub 2} = 0.2 atm). In NaHCO{sub 3} solutions with lower carbonate concentrations (0.98--1.96 mmol/l) and in Allard groundwater they were close to the calculated solubilities of U at the U{sub 3}O{sub 7}/U{sub 3}O{sub 8} redox potential. In bentonite groundwater, the results suggest the formation of a secondary phase with a lower solubility. Only uranium oxide with a crystal structure of uraninite (UO{sub 2}-U{sub 3}O{sub 7}) was identified in all waters, when analyzing particulate material in the solutions after contact with UO{sub 2} pellets.

  2. Entanglement patterns in mutually unbiased basis sets

    SciTech Connect

    Lawrence, Jay

    2011-08-15

    A few simply stated rules govern the entanglement patterns that can occur in mutually unbiased basis sets (MUBs) and constrain the combinations of such patterns that can coexist in full complements of MUBs. We consider Hilbert spaces of prime power dimensions (D=p{sup N}), as realized by systems of N prime-state particles, where full complements of D+1 MUBs are known to exist, and we assume only that MUBs are eigenbases of generalized Pauli operators, without using any particular construction. The general rules include the following: (1) In any MUB, a given particle appears either in a pure state or totally entangled and (2) in any full MUB complement, each particle is pure in (p+1) bases (not necessarily the same ones) and totally entangled in the remaining (p{sup N}-p). It follows that the maximum number of product bases is p+1 and, when this number is realized, all remaining (p{sup N}-p) bases in the complement are characterized by the total entanglement of every particle. This ''standard distribution'' is inescapable for two-particle systems (of any p), where only product and generalized Bell bases are admissible MUB types. This and the following results generalize previous results for qubits [Phys. Rev. A 65. 032320 (2002); Phys. Rev. A 72, 062310 (2005)] and qutrits [Phys. Rev. A 70, 012302 (2004)], drawing particularly upon [Phys. Rev. A 72, 062310 (2005)]. With three particles there are three MUB types, and these may be combined in (p+2) different ways to form full complements. With N=4, there are 6 MUB types for p=2, but new MUB types become possible with larger p, and these are essential to realizing full complements. With this example, we argue that new MUB types that show new entanglement patterns should enter with every step in N and, also, when N is a prime plus 1, at a critical p value, p=N-1. Such MUBs should play critical roles in filling complements.

  3. Jupiter and Mutual Satellite Occultations of Io from 1985 to 2015

    NASA Astrophysics Data System (ADS)

    Howell, Robert R.; Rathbun, Julie A.; Spencer, John R.

    2016-10-01

    Occultations of Io by Jupiter and by other satellites provide a long-term record of the brightness of individual volcanic hotspots. They also provide our highest spatial resolution observations of individual volcanic centers such as Loki. We are in the process of reanalyzing observations spanning the years 1985 through 2015 for submission to the NASA Planetary Data System. The Jupiter occultation observations have spatial resolution limited to roughly the Jupiter atmospheric scale height (22 km) but as these events occur every Io orbit we have data on over 100. They include observations from the NASA-IRTF, WIRO, Lowell, and other telescopes on Mauna Kea. Part of this data set originally revealed the semi-periodic nature of the activity at Loki (Rathbun et al. 2002). A series of mutual satellite occultations occurs only every six years but the sharp limb of the other satellite allows for much higher spatial resolution. The original analysis was limited by inaccuracies in the satellite ephemerides but improvements now allow us to more reliably assign brightnesses to individual hotspots. They also allow improved image reconstructions of individual spots from mutual events. We will report on our tests of that better ephemeris, the improved assignment of hotspot brightnesses, and the reconstructed mutual event images.

  4. Intercontinental differences in resource use reveal the importance of mutualisms in fire ant invasions

    PubMed Central

    Wilder, Shawn M.; Holway, David A.; Suarez, Andrew V.; LeBrun, Edward G.; Eubanks, Micky D.

    2011-01-01

    Mutualisms play key roles in the functioning of ecosystems. However, reciprocally beneficial interactions that involve introduced species also can enhance invasion success and in doing so compromise ecosystem integrity. For example, the growth and competitive ability of introduced plant species can increase when fungal or microbial associates provide limiting nutrients. Mutualisms also may aid animal invasions, but how such systems may promote invasion success has received relatively little attention. Here we examine how access to food-for-protection mutualisms involving the red imported fire ant (Solenopsis invicta) aids the success of this prominent invader. Intense interspecific competition in its native Argentina constrained the ability of S. invicta to benefit from honeydew-producing Hemiptera (and other accessible sources of carbohydrates), whereas S. invicta dominated these resources in its introduced range in the United States. Consistent with this strong pattern, nitrogen isotopic data revealed that fire ants from populations in the United States occupy a lower trophic position than fire ants from Argentina. Laboratory and field experiments demonstrated that honeydew elevated colony growth, a crucial determinant of competitive performance, even when insect prey were not limiting. Carbohydrates, obtained largely through mutualistic partnerships with other organisms, thus represent critical resources that may aid the success of this widespread invasive species. These results illustrate the potential for mutualistic interactions to play a fundamental role in the establishment and spread of animal invasions. PMID:22143788

  5. A novel mutualism between an ant-plant and its resident pollinator

    NASA Astrophysics Data System (ADS)

    Shenoy, Megha; Borges, Renee M.

    2008-01-01

    Pollination systems in which the host plant provides breeding sites for pollinators, invariably within flowers, are usually highly specialized mutualisms. We found that the pollinating bee Braunsapis puangensis breeds within the caulinary domatia of the semi-myrmecophyte Humboldtia brunonis (Fabaceae), an unusual ant-plant that is polymorphic for the presence of domatia and harbours a diverse invertebrate fauna including protective and non-protective ants in its domatia. B. puangensis is the most common flower visitor that carries the highest proportion of H. brunonis pollen. This myrmecophyte is pollen limited and cross-pollinated by bees in the daytime. Hence, the symbiotic pollinator could provide a benefit to trees bearing domatia by alleviating this limitation. We therefore report for the first time an unspecialised mutualism in which a pollinator is housed in a plant structure other than flowers. Here, the cost to the plant is lower than for conventional brood-site pollination mutualisms where the pollinator develops at the expense of plant reproductive structures. Myrmecophytes housing resident pollinators are unusual, as ants are known to be enemies of pollinators, and housing them together may decrease the benefits that these residents could individually provide to the host plant.

  6. Mutualism or parasitism? The variable outcome of cleaning symbioses

    PubMed Central

    Cheney, Karen L; Côté, Isabelle M

    2005-01-01

    The exact nature of many interspecific interactions remains unclear, with some evidence suggesting mutualism and other evidence pointing to parasitism for the same pair of interacting species. Here, we show spatial variation in the outcome of the cleaning relationship between Caribbean cleaning gobies (Elacatinus evelynae) and longfin damselfish (Stegastes diencaeus) over the distribution range of these species, and link this variation to the availability of ectoparasites. Cleaning interactions at sites with more ectoparasites were characterized by greater reductions in ectoparasite loads on damselfish clients and lower rates of removal of scales and mucus (i.e. cheating) by cleaning gobies, whereas the opposite was observed at sites where ectoparasite abundance was lower. For damselfish clients, cleaning was therefore clearly mutualistic in some locations, but sometimes neutral or even parasitic in others. Seasonal variability in ectoparasite abundance may ensure that locally low parasite availability, which promotes cleanerfish cheating, may be a transient condition at any given site. Conflicting conclusions about the nature of cleaning symbioses may, therefore, be explained by variation in ectoparasite abundance. PMID:17148155

  7. Pupil dilation as an index of preferred mutual gaze duration

    PubMed Central

    Binetti, Nicola; Harrison, Charlotte; Coutrot, Antoine; Johnston, Alan; Mareschal, Isabelle

    2016-01-01

    Most animals look at each other to signal threat or interest. In humans, this social interaction is usually punctuated with brief periods of mutual eye contact. Deviations from this pattern of gazing behaviour generally make us feel uncomfortable and are a defining characteristic of clinical conditions such as autism or schizophrenia, yet it is unclear what constitutes normal eye contact. Here, we measured, across a wide range of ages, cultures and personality types, the period of direct gaze that feels comfortable and examined whether autonomic factors linked to arousal were indicative of people's preferred amount of eye contact. Surprisingly, we find that preferred period of gaze duration is not dependent on fundamental characteristics such as gender, personality traits or attractiveness. However, we do find that subtle pupillary changes, indicative of physiological arousal, correlate with the amount of eye contact people find comfortable. Specifically, people preferring longer durations of eye contact display faster increases in pupil size when viewing another person than those preferring shorter durations. These results reveal that a person's preferred duration of eye contact is signalled by physiological indices (pupil dilation) beyond volitional control that may play a modulatory role in gaze behaviour. PMID:27493767

  8. Mutual information and redundancy in spontaneous communication between cortical neurons.

    PubMed

    Szczepanski, J; Arnold, M; Wajnryb, E; Amigó, J M; Sanchez-Vives, M V

    2011-03-01

    An important question in neural information processing is how neurons cooperate to transmit information. To study this question, we resort to the concept of redundancy in the information transmitted by a group of neurons and, at the same time, we introduce a novel concept for measuring cooperation between pairs of neurons called relative mutual information (RMI). Specifically, we studied these two parameters for spike trains generated by neighboring neurons from the primary visual cortex in the awake, freely moving rat. The spike trains studied here were spontaneously generated in the cortical network, in the absence of visual stimulation. Under these conditions, our analysis revealed that while the value of RMI oscillated slightly around an average value, the redundancy exhibited a behavior characterized by a higher variability. We conjecture that this combination of approximately constant RMI and greater variable redundancy makes information transmission more resistant to noise disturbances. Furthermore, the redundancy values suggest that neurons can cooperate in a flexible way during information transmission. This mostly occurs via a leading neuron with higher transmission rate or, less frequently, through the information rate of the whole group being higher than the sum of the individual information rates-in other words in a synergetic manner. The proposed method applies not only to the stationary, but also to locally stationary neural signals.

  9. Apport maternel chez la balane tropicale : Plasticite de l'allocation de la ressource trophique pour la production larvaire en conditions de limitation nutritionnelle et de stress environnemental

    NASA Astrophysics Data System (ADS)

    Freuchet, Florian

    Dans le milieu marin, l'abondance du recrutement depend des processus qui vont affecter les adultes et le stock de larves. Sous l'influence de signaux fiables de la qualite de l'habitat, la mere peut augmenter (effet maternel anticipatoire, 'anticipatory mother effects', AME) ou reduire (effet maternel egoiste, 'selfish maternai effects', SME) la condition physiologique de la progeniture. Dans les zones tropicales, generalement plus oligotrophes, la ressource nutritive et la temperature sont deux composantes importantes pouvant limiter le recrutement. Les effets de l'apport nutritionnel et du stress thermique sur la production de larves et sur la stategie maternelle adoptee ont ete testes dans cette etude. Nous avons cible la balane Chthamalus bisinuatus (Pilsbry) comme modele biologique car el1e domine les zones intertidales superieures le long des cotes rocheuses du Sud-Est du Bresil (region tropicale). Les hypotheses de depart stipulaient que l'apport nutritionnel permet aux adultes de produire des larves de qualite elevee et que le stress thermique genere une ponte precoce, produisant des larves de faible qualite. Afin de tester ces hypotheses, des populations de C. bisinuatus ont ete elevees selon quatre groupes experimentaux differents, en combinant des niveaux d'apport nutritionnel (eleve et faible) et de stress thermique (stresse et non stresse). Des mesures de survie et de conditions physiologiques des adultes et des larves ont permis d'identifier les reponses parentales pouvant etre avantageuses dans un environnement tropical hostile. L'analyse des profils en acides gras a ete la methode utilisee pour evaluer la qualite physiologique des adultes et de larves. Les resultats du traitement alimentaire (fort ou faible apport nutritif), ne montrent aucune difference dans l'accumulation de lipides neutres, la taille des nauplii, l'effort de reproduction ou le temps de survie des nauplii en condition de jeune. Il semble que la faible ressource nutritive est

  10. Quantitative proteomic view on secreted, cell surface-associated, and cytoplasmic proteins of the methicillin-resistant human pathogen Staphylococcus aureus under iron-limited conditions.

    PubMed

    Hempel, Kristina; Herbst, Florian-Alexander; Moche, Martin; Hecker, Michael; Becher, Dörte

    2011-04-01

    Staphylococcus aureus is capable of colonizing and infecting humans by its arsenal of surface-exposed and secreted proteins. Iron-limited conditions in mammalian body fluids serve as a major environmental signal to bacteria to express virulence determinants. Here we present a comprehensive, gel-free, and GeLC-MS/MS-based quantitative proteome profiling of S. aureus under this infection-relevant situation. (14)N(15)N metabolic labeling and three complementing approaches were combined for relative quantitative analyses of surface-associated proteins. The surface-exposed and secreted proteome profiling approaches comprise trypsin shaving, biotinylation, and precipitation of the supernatant. By analysis of the outer subproteomic and cytoplasmic protein fraction, 1210 proteins could be identified including 221 surface-associated proteins. Thus, access was enabled to 70% of the predicted cell wall-associated proteins, 80% of the predicted sortase substrates, two/thirds of lipoproteins and more than 50% of secreted and cytoplasmic proteins. For iron-deficiency, 158 surface-associated proteins were quantified. Twenty-nine proteins were found in altered amounts showing particularly surface-exposed proteins strongly induced, such as the iron-regulated surface determinant proteins IsdA, IsdB, IsdC and IsdD as well as lipid-anchored iron compound-binding proteins. The work presents a crucial subject for understanding S. aureus pathophysiology by the use of methods that allow quantitative surface proteome profiling.

  11. A New Methodology for Open Pit Slope Design in Karst-Prone Ground Conditions Based on Integrated Stochastic-Limit Equilibrium Analysis

    NASA Astrophysics Data System (ADS)

    Zhang, Ke; Cao, Ping; Ma, Guowei; Fan, Wenchen; Meng, Jingjing; Li, Kaihui

    2016-07-01

    Using the Chengmenshan Copper Mine as a case study, a new methodology for open pit slope design in karst-prone ground conditions is presented based on integrated stochastic-limit equilibrium analysis. The numerical modeling and optimization design procedure contain a collection of drill core data, karst cave stochastic model generation, SLIDE simulation and bisection method optimization. Borehole investigations are performed, and the statistical result shows that the length of the karst cave fits a negative exponential distribution model, but the length of carbonatite does not exactly follow any standard distribution. The inverse transform method and acceptance-rejection method are used to reproduce the length of the karst cave and carbonatite, respectively. A code for karst cave stochastic model generation, named KCSMG, is developed. The stability of the rock slope with the karst cave stochastic model is analyzed by combining the KCSMG code and the SLIDE program. This approach is then applied to study the effect of the karst cave on the stability of the open pit slope, and a procedure to optimize the open pit slope angle is presented.

  12. Acclimation conditions modify physiological response of the diatom Thalassiosira pseudonana to elevated CO2 concentrations in a nitrate-limited chemostat.

    PubMed

    Hennon, Gwenn M M; Quay, Paul; Morales, Rhonda L; Swanson, Lyndsey M; Virginia Armbrust, E

    2014-04-01

    Diatoms are responsible for a large proportion of global carbon fixation, with the possibility that they may fix more carbon under future levels of high CO2 . To determine how increased CO2 concentrations impact the physiology of the diatom Thalassiosira pseudonana Hasle et Heimdal, nitrate-limited chemostats were used to acclimate cells to a recent past (333 ± 6 μatm) and two projected future concentrations (476 ± 18 μatm, 816 ± 35 μatm) of CO2 . Samples were harvested under steady-state growth conditions after either an abrupt (15-16 generations) or a longer acclimation process (33-57 generations) to increased CO2 concentrations. The use of un-bubbled chemostat cultures allowed us to calculate the uptake ratio of dissolved inorganic carbon relative to dissolved inorganic nitrogen (DIC:DIN), which was strongly correlated with fCO2 in the shorter acclimations but not in the longer acclimations. Both CO2 treatment and acclimation time significantly affected the DIC:DIN uptake ratio. Chlorophyll a per cell decreased under elevated CO2 and the rates of photosynthesis and respiration decreased significantly under higher levels of CO2 . These results suggest that T. pseudonana shifts carbon and energy fluxes in response to high CO2 and that acclimation time has a strong effect on the physiological response.

  13. Initial Piloted Simulation Evaluation of the Reference-H High-Speed Civil Transport Design During Takeoff and Recovery From Limit Flight Conditions

    NASA Technical Reports Server (NTRS)

    Glaab, Louis J.

    1999-01-01

    An initial assessment of a proposed High-Speed Civil Transport (HSCT) was conducted in the fall of 1995 at the NASA Langley Research Center. This configuration, known as the Industry Reference-H (Ref.-H), was designed by the Boeing Aircraft Company as part of their work in the High Speed Research program. It included a conventional tail, a cranked-arrow wing, four mixed-flow turbofan engines, and capacity for transporting approximately 300 passengers. The purpose of this assessment was to evaluate and quantify operational aspects of the Reference-H configuration from a pilot's perspective with the additional goal of identifying design strengths as well as any potential configuration deficiencies. This study was aimed at evaluating the Ref.-H configuration at many points of the aircraft's envelope to determine the suitability of the vehicle to accomplish typical mission profiles as well as emergency or envelope-limit conditions. Pilot-provided Cooper-Harper ratings and comments constituted the primary vehicle evaluation metric. The analysis included simulated real-time piloted evaluations, performed in a 6 degree of freedom motion base NASA Langley Visual-Motion Simulator, combined with extensive bath analysis. The assessment was performed using the third major release of the simulation data base (known as Ref.-H cycle 2B).

  14. Footprint area analysis of binary imaged Cupriavidus necator cells to study PHB production at balanced, transient, and limited growth conditions in a cascade process.

    PubMed

    Vadlja, Denis; Koller, Martin; Novak, Mario; Braunegg, Gerhart; Horvat, Predrag

    2016-12-01

    Statistical distribution of cell and poly[3-(R)-hydroxybutyrate] (PHB) granule size and number of granules per cell are investigated for PHB production in a five-stage cascade (5CSTR). Electron microscopic pictures of cells from individual cascade stages (R1-R5) were converted to binary pictures to visualize footprint areas for polyhydroxyalkanoate (PHA) and non-PHA biomass. Results for each stage were correlated to the corresponding experimentally determined kinetics (specific growth rate μ and specific productivity π). Log-normal distribution describes PHA granule size dissimilarity, whereas for R1 and R4, gamma distribution best reflects the situation. R1, devoted to balanced biomass synthesis, predominately contains cells with rather small granules, whereas with increasing residence time τ, maximum and average granule sizes by trend increase, approaching an upper limit determined by the cell's geometry. Generally, an increase of intracellular PHA content and ratio of granule to cell area slow down along the cascade. Further, the number of granules per cell decreases with increasing τ. Data for μ and π obtained by binary picture analysis correlate well with the experimental results. The work describes long-term continuous PHA production under balanced, transient, and nutrient-deficient conditions, as well as their reflection on the granules size, granule number, and cell structure on the microscopic level.

  15. Metabolic and transcriptomic response of the wine yeast Saccharomyces cerevisiae strain EC1118 after an oxygen impulse under carbon-sufficient, nitrogen-limited fermentative conditions.

    PubMed

    Orellana, Marcelo; Aceituno, Felipe F; Slater, Alex W; Almonacid, Leonardo I; Melo, Francisco; Agosin, Eduardo

    2014-05-01

    During alcoholic fermentation, Saccharomyces cerevisiae is exposed to continuously changing environmental conditions, such as decreasing sugar and increasing ethanol concentrations. Oxygen, a critical nutrient to avoid stuck and sluggish fermentations, is only discretely available throughout the process after pump-over operation. In this work, we studied the physiological response of the wine yeast S. cerevisiae strain EC1118 to a sudden increase in dissolved oxygen, simulating pump-over operation. With this aim, an impulse of dissolved oxygen was added to carbon-sufficient, nitrogen-limited anaerobic continuous cultures. Results showed that genes related to mitochondrial respiration, ergosterol biosynthesis, and oxidative stress, among other metabolic pathways, were induced after the oxygen impulse. On the other hand, mannoprotein coding genes were repressed. The changes in the expression of these genes are coordinated responses that share common elements at the level of transcriptional regulation. Beneficial and detrimental effects of these physiological processes on wine quality highlight the dual role of oxygen in 'making or breaking wines'. These findings will facilitate the development of oxygen addition strategies to optimize yeast performance in industrial fermentations.

  16. 47 CFR 27.321 - Mutually exclusive applications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and Processing Rules for WCS § 27.321... Commission's rules governing the Wireless Communications Services involved. The Commission uses the general procedures in this section for processing mutually exclusive applications in the Wireless...

  17. 47 CFR 27.321 - Mutually exclusive applications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and Processing Rules for WCS § 27.321... Commission's rules governing the Wireless Communications Services involved. The Commission uses the general procedures in this section for processing mutually exclusive applications in the Wireless...

  18. 47 CFR 27.321 - Mutually exclusive applications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and Processing Rules for WCS § 27.321... Commission's rules governing the Wireless Communications Services involved. The Commission uses the general procedures in this section for processing mutually exclusive applications in the Wireless...

  19. 47 CFR 27.321 - Mutually exclusive applications.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and Processing Rules for WCS § 27.321... Commission's rules governing the Wireless Communications Services involved. The Commission uses the general procedures in this section for processing mutually exclusive applications in the Wireless...

  20. 47 CFR 27.321 - Mutually exclusive applications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and Processing Rules for WCS § 27.321... Commission's rules governing the Wireless Communications Services involved. The Commission uses the general procedures in this section for processing mutually exclusive applications in the Wireless...

  1. Mutual intentions as a causal framework for social groups.

    PubMed

    Noyes, Alexander; Dunham, Yarrow

    2017-02-24

    Children's early emerging intuitive theories are specialized for different conceptual domains. Recently attention has turned to children's concepts of social groups, finding that children believe that many social groups mark uniquely social information such as allegiances and obligations. But another critical component of intuitive theories, the causal beliefs that underlie category membership, has received less attention. We propose that children believe membership in these groups is constituted by mutual intentions: i.e., all group members (including the individual) intend for an individual to be a member and all group members (including the individual) have common knowledge of these intentions. Children in a broad age range (4-9) applied a mutual-intentional framework to newly encountered social groups early in development (Experiment 1, 2, 4). Further, they deploy this mutual-intentional framework selectively, withholding it from essentialized social categories such as gender (Experiment 3). Mutual intentionality appears to be a vital aspect of children's naïve sociology.

  2. Nonlinear pattern analysis of ventricular premature beats by mutual information

    NASA Technical Reports Server (NTRS)

    Osaka, M.; Saitoh, H.; Yokoshima, T.; Kishida, H.; Hayakawa, H.; Cohen, R. J.

    1997-01-01

    The frequency of ventricular premature beats (VPBs) has been related to the risk of mortality. However, little is known about the temporal pattern of occurrence of VPBs and its relationship to autonomic activity. Hence, we applied a general correlation measure, mutual information, to quantify how VPBs are generated over time. We also used mutual information to determine the correlation between VPB production and heart rate in order to evaluate effects of autonomic activity on VPB production. We examined twenty subjects with more than 3000 VPBs/day and simulated random time series of VPB occurrence. We found that mutual information values could be used to characterize quantitatively the temporal patterns of VPB generation. Our data suggest that VPB production is not random and VPBs generated with a higher value of mutual information may be more greatly affected by autonomic activity.

  3. Mutual impedance of nonplanar-skew sinusoidal dipoles

    NASA Technical Reports Server (NTRS)

    Richmond, J. H.; Geary, N. H.

    1975-01-01

    The mutual impedance expressions for parallel dipoles in terms of sine-integrals and cosine-integrals have been published by King (1957). The investigation reported provides analogous expressions for nonparallel dipoles. The expressions presented are most useful when the monopoles are close together. The theory of moment methods shows an approach for employing the mutual impedance of filamentary sinusoidal dipoles to calculate the impedance and scattering properties of straight and bent wires with small but finite diameter.

  4. Viscosity and mutual diffusion in strongly asymmetric binary ionic mixtures

    SciTech Connect

    Bastea, Sorin

    2005-05-01

    We present molecular dynamics simulation results for the viscosity and mutual diffusion constant of a strongly asymmetric binary ionic mixture. We compare the results with available theoretical models previously tested for much smaller asymmetries. For the case of viscosity we propose a predictive framework based on the linear mixing rule, while for mutual diffusion we discuss some consistency problems of widely used Boltzmann-equation-based models.

  5. Viscosity and mutual diffusion in strongly asymmetric plasma mixtures

    SciTech Connect

    Bastea, S

    2004-09-07

    The authors present molecular dynamics simulation results for the viscosity and mutual diffusion constant of a strongly asymmetric two-component plasma (TCP). They compare the results with available theoretical models previously tested for much smaller asymmetries. for the case of viscosity they propose a new predictive framework based on the linear mixing rule, while for mutual diffusion they point out some consistency problems of widely used Boltzmann equation based models.

  6. Quantum process reconstruction based on mutually unbiased basis

    SciTech Connect

    Fernandez-Perez, A.; Saavedra, C.; Klimov, A. B.

    2011-05-15

    We study a quantum process reconstruction based on the use of mutually unbiased projectors (MUB projectors) as input states for a D-dimensional quantum system, with D being a power of a prime number. This approach connects the results of quantum-state tomography using mutually unbiased bases with the coefficients of a quantum process, expanded in terms of MUB projectors. We also study the performance of the reconstruction scheme against random errors when measuring probabilities at the MUB projectors.

  7. Non-rigid registration using higher-order mutual information

    NASA Astrophysics Data System (ADS)

    Rueckert, D.; Clarkson, M. J.; Hill, D. L. G.; Hawkes, D. J.

    2000-03-01

    Non-rigid registration of multi-modality images is an important tool for assessing temporal and structural changesbetween images. For rigid registration, voxel similarity measures like mutual information have been shown to alignimages from different modalities accurately and robustly. For non-rigid registration, mutual information can besensitive to local variations of intensity which in MR images may be caused by RF inhomogeneity. The reasonfor the sensitivity of mutual information towards intensity variations stems from the fact that mutual informationignores any spatial information. In this paper we propose an extension of the mutual information framework whichincorporates spatial information about higher-order image structure into the registration process and has the potentialto improve the accuracy and robustness of non-rigid registration in the presence of intensity variations. We haveapplied the non-rigid registration algorithm to a number of simulated MR brain images of a digital phantom whichhave been degraded by a simulated intensity shading and a known deformation. In addition, we have applied thealgorithm for the non-rigid registration of eight pre- and post-operative brain MR images which were acquired withan interventional MR scanner and therefore have substantial intensity shading due to RF field inhomogeneities. Inall cases the second-order estimate of mutual information leads to robust and accurate registration.

  8. An invasive plant-fungal mutualism reduces arthropod diversity.

    PubMed

    Rudgers, Jennifer A; Clay, Keith

    2008-08-01

    Ecological theory holds that competition and predation are the most important biotic forces affecting the composition of communities. Here, we expand this framework by demonstrating that mutualism can fundamentally alter community and food web structure. In large, replicated field plots, we manipulated the mutualism between a dominant plant (Lolium arundinaceum) and symbiotic fungal endophyte (Neotyphodium coenophialum). The presence of the mutualism reduced arthropod abundance up to 70%, reduced arthropod diversity nearly 20%, shifted arthropod species composition relative to endophyte-free plots and suppressed the biomass and richness of other plant species in the community. Herbivorous arthropods were more strongly affected than carnivores, and for both herbivores and carnivores, effects of the mutualism appeared to propagate indirectly via organisms occurring more basally in the food web. The influence of the mutualism was as great or greater than previously documented effects of competition and predation on arthropod communities. Our work demonstrates that a keystone mutualism can significantly reduce arthropod biodiversity at a broad community scale.

  9. Spectral image analysis of mutual illumination between florescent objects.

    PubMed

    Tominaga, Shoji; Kato, Keiji; Hirai, Keita; Horiuchi, Takahiko

    2016-08-01

    This paper proposes a method for modeling and component estimation of the spectral images of the mutual illumination phenomenon between two fluorescent objects. First, we briefly describe the bispectral characteristics of a single fluorescent object, which are summarized as a Donaldson matrix. We suppose that two fluorescent objects with different bispectral characteristics are located close together under a uniform illumination. Second, we model the mutual illumination between two objects. It is shown that the spectral composition of the mutual illumination is summarized with four components: (1) diffuse reflection, (2) diffuse-diffuse interreflection, (3) fluorescent self-luminescence, and (4) interreflection by mutual fluorescent illumination. Third, we develop algorithms for estimating the spectral image components from the observed images influenced by the mutual illumination. When the exact Donaldson matrices caused by the mutual illumination influence are unknown, we have to solve a non-linear estimation problem to estimate both the spectral functions and the location weights. An iterative algorithm is then proposed to solve the problem based on the alternate estimation of the spectral functions and the location weights. In our experiments, the feasibility of the proposed method is shown in three cases: the known Donaldson matrices, weak interreflection, and strong interreflection.

  10. Effects of mutual shading on the regulation of photosynthesis in field-grown sorghum.

    PubMed

    Li, Tao; Liu, Li-Na; Jiang, Chuang-Dao; Liu, Yu-Jun; Shi, Lei

    2014-08-01

    In the field, close planting inevitably causes mutual shading and depression of leaf photosynthesis. To clarify the regulative mechanisms of photosynthesis under these conditions, the effects of planting density on leaf structure, gas exchange and proteomics were carefully studied in field-grown sorghum. In the absence of mineral deficiency, (1) close planting induced a significant decrease in light intensity within populations, which further resulted in much lower stomatal density and other anatomical characteristics associated with shaded leaves; (2) sorghum grown at high planting density had a lower net photosynthetic rate and stomatal conductance than those grown at low planting density; (3) approximately 62 protein spots changed their expression levels under the high planting density conditions, and 22 proteins associated with photosynthesis were identified by mass spectrometry. Further analysis revealed the depression of photosynthesis caused by mutual shading involves the regulation of leaf structure, absorption and transportation of CO2, photosynthetic electron transport, production of assimilatory power, and levels of enzymes related to the Calvin cycle. Additionally, heat shock protein and oxygen-evolving enhancer protein play important roles in photoprotection in field-grown sorghum. A model for the regulation of photosynthesis under mutual shading was suggested based on our results.

  11. Strain localization in brittle-ductile shear zones: fluid-abundant vs. fluid-limited conditions (an example from Wyangala area, Australia)

    NASA Astrophysics Data System (ADS)

    Spruzeniece, L.; Piazolo, S.

    2015-07-01

    This study focuses on physiochemical processes occurring in a brittle-ductile shear zone at both fluid-present and fluid-limited conditions. In the studied shear zone (Wyangala, SE Australia), a coarse-grained two-feldspar-quartz-biotite granite is transformed into a medium-grained orthogneiss at the shear zone margins and a fine-grained quartz-muscovite phyllonite in the central parts. The orthogneiss displays cataclasis of feldspar and crystal-plastic deformation of quartz. Quartz accommodates most of the deformation and is extensively recrystallized, showing distinct crystallographic preferred orientation (CPO). Feldspar-to-muscovite, biotite-to-muscovite and albitization reactions occur locally at porphyroclasts' fracture surfaces and margins. However, the bulk rock composition shows very little change in respect to the wall rock composition. In contrast, in the shear zone centre quartz occurs as large, weakly deformed porphyroclasts in sizes similar to that in the wall rock, suggesting that it has undergone little deformation. Feldspars and biotite are almost completely reacted to muscovite, which is arranged in a fine-grained interconnected matrix. Muscovite-rich layers contain significant amounts of fine-grained intermixed quartz with random CPO. These domains are interpreted to have accommodated most of the strain. Bulk rock chemistry data show a significant increase in SiO2 and depletion in NaO content compared to the wall rock composition. We suggest that the high- and low-strain microstructures in the shear zone represent markedly different scenarios and cannot be interpreted as a simple sequential development with respect to strain. Instead, we propose that the microstructural and mineralogical changes in the shear zone centre arise from a local metasomatic alteration around a brittle precursor. When the weaker fine-grained microstructure is established, the further flow is controlled by transient porosity created at (i) grain boundaries in fine

  12. Increased belowground C release during initial plant development of Populus deltoides x nigra grown under light and C reserve limited conditions

    NASA Astrophysics Data System (ADS)

    Studer, Mirjam S.; Siegwolf, Rolf T. W.; Schmidt, Michael W. I.; Abiven, Samuel

    2014-05-01

    Plants might be a key factor for the long-term stabilisation of carbon (C) in the soil, e.g. through enhanced physical protection of root-derived C against microbial decomposition in soil aggregates. On the other hand C released by the plants into the soil might promote the decomposition of native soil organic matter (SOM) through the stimulation of microbial activity. We measured the C budget of developing plant-soil systems (Populus deltoides x nigra, Cambisol soil) in the laboratory under controlled environmental conditions. In order to distinguish plant-derived from native C in the SOM and the soil CO2 efflux, we labelled the poplar shoots continuously with 13C-CO2 from first emergence of leaves (sprouting from stem cuttings). Throughout the experiment the CO2 fluxes (photosynthetic assimilation, dark respiratory loss, soil CO2 efflux) were measured frequently (every 30 min) and the 13C was traced in the soil CO2 efflux (1-2 times a week). After 10 weeks the plant-soil systems were destructively harvested and the distribution of the 13C distribution was analysed. The plants developed slowly (compared to previous experiments), most likely due to limitation in C reserves (long term cutting storage) and C supply (low light intensities). The amount of 13C recovered in the roots, microbial biomass and soil CO2 efflux was directly correlated with the leaf area of the different plant individuals. After 3-4 weeks of plant development we observed a high peak in the total soil CO2 efflux. During this time the relative belowground C release was increased massively over the basal rate of 17 % of net C assimilated, whereby the variability between the plant individuals was large. The smallest plants, i.e. the plants that were most resource limited, obtained the highest belowground C release accounting at the peak time for up to 57 % of net assimilated C. We hypothesize that the plants released specific compounds, which either directly (enzymatically) or indirectly (priming

  13. Mutual synchronization of oscillating pulse edges in point-coupled transmission lines with regularly spaced tunnel diodes

    NASA Astrophysics Data System (ADS)

    Narahara, Koichi

    2017-01-01

    In this paper, we investigate the mutual synchronization of oscillating pulse edges developed in point-coupled transmission lines periodically loaded with tunnel diodes (TDs). When supplied with an appropriate voltage at the end of a TD line, a pulse edge exhibits a spatially extended limit-cycle oscillation on the line. In this study, the properties of this mutual synchronization of edge oscillation established in two coupled TD lines are discussed. We examine the mutual synchronization using phase sensitivity calculated by applying phase-reduction scheme to the transmission equation of a TD line. The phase difference between the synchronized edges and oscillation frequency is calculated depending on the coupling cell. We then validate the reduced model via time-domain calculations of edge oscillations.

  14. A mechanistic molecular test of the plant-sanction hypothesis in legume-rhizobia mutualism

    NASA Astrophysics Data System (ADS)

    Marco, Diana E.; Pérez-Arnedo, Rebeca; Hidalgo-Perea, Ángeles; Olivares, José; Ruiz-Sainz, José E.; Sanjuán, Juan

    2009-09-01

    The origin and persistence of mutualism is difficult to explain because of the widespread occurrence of exploitative, 'cheating' partners. As a policing strategy stabilising intraspecific cooperation, host sanctions against non-N 2 fixing, cheating symbionts have been proposed to stabilise mutualism in legume-rhizobium symbiosis. Mechanism of penalisations would include decreased nodular rhizobial viability and/or early nodule senescence. We tested these potential mechanisms of penalisations in split-root experiments using two soybean varieties and two rhizobial strains, a cooperative, normal N 2-fixing strain and an isogenic non-fixing derivative. We found no differences in the number of viable rhizobia recovered from nodules and no differential expression of a nodular senescence molecular marker. Thus, our results do not support the hypothesis of plant sanctions acting against cheating rhizobia in our experimental conditions.

  15. Plant-fungal ecology. Niche engineering demonstrates a latent capacity for fungal-algal mutualism.

    PubMed

    Hom, Erik F Y; Murray, Andrew W

    2014-07-04

    Mutualistic symbioses shape the evolution of species and ecosystems and catalyze the emergence of biological complexity, yet how such symbioses first form is unclear. We show that an obligate mutualism between the yeast Saccharomyces cerevisiae and the alga Chlamydomonas reinhardtii--two model eukaryotes with very different life histories--can arise spontaneously in an environment requiring reciprocal carbon and nitrogen exchange. This capacity for mutualism is phylogenetically broad, extending to other Chlamydomonas and fungal species. Furthermore, we witnessed the spontaneous association of Chlamydomonas algal cells physically interacting with filamentous fungi. These observations demonstrate that under specific conditions, environmental change induces free-living species to become obligate mutualists and establishes a set of experimentally tractable, phylogenetically related, synthetic systems for studying the evolution of symbiosis.

  16. Entanglement and nonclassicality: A mutual impression

    NASA Astrophysics Data System (ADS)

    Gholipour, H.; Shahandeh, F.

    2016-06-01

    We find a sufficient condition to imprint the single-mode bosonic phase-space nonclassicality onto a bipartite state as modal entanglement and vice versa using an arbitrary beam splitter. Surprisingly, the entanglement produced or detected in this way depends only on the nonclassicality of the marginal input or output states, regardless of their purity and separability. In this way, our result provides a sufficient condition for generating entangled states of arbitrary high temperature and arbitrary large number of particles. We also study the evolution of the entanglement within a lossy Mach-Zehnder interferometer and show that unless both modes are totally lost, the entanglement does not diminish.

  17. How to become a yucca moth: Minimal trait evolution needed to establish the obligate pollination mutualism.

    PubMed

    Yoder, Jeremy B; Smith, Christopher Irwin; Pellmyr, Olle

    2010-08-01

    The origins of obligate pollination mutualisms, such as the classic yucca-yucca moth association, appear to require extensive trait evolution and specialization. To understand the extent to which traits truly evolved as part of establishing the mutualistic relationship, rather than being preadaptations, we used an expanded phylogenetic estimate with improved sampling of deeply-diverged groups to perform the first formal reconstruction of trait evolution in pollinating yucca moths and their non-pollinating relatives. Our analysis demonstrates that key life history traits of yucca moths, including larval feeding in the floral ovary and the associated specialized cutting ovipositor, as well as colonization of woody monocots in xeric habitats, may have been established before the obligate mutualism with yuccas. Given these preexisting traits, novel traits in the mutualist moths are limited to the active pollination behaviors and the tentacular appendages that facilitate pollen collection and deposition. These results suggest that a highly specialized obligate mutualism was built on the foundation of preexisting interactions between early Prodoxidae and their host plants, and arose with minimal trait evolution.

  18. Ecology of yeasts in plant-bumblebee mutualism in Central Europe.

    PubMed

    Brysch-Herzberg, Michael

    2004-11-01

    Yeast community involved in plant-bumblebee mutualism was investigated in three successive years. Yeasts were isolated from floral nectar, bumblebee queens after hibernation, bumblebee workers, and the honey provisions in nests. From the distribution of yeast species in the various microhabitats in the course of the year their ecology was assessed. Nectar of numerous plant species belonging to various plant families was analyzed in order to uncover possible impacts on the yeasts present in the nectar. Only ascomycetous yeasts were autochthonous members of the communities in the plant-bumblebee mutualism. Species in the Metschnikowia clade, the Starmarella clade, and the genera Debaryomyces and Zygosaccharomyces were associated with the mutualism. Some species appeared highly specialized, whereas others had a broader distribution. While physical and chemical properties of nectar had only limited influence on the abundance of nectar yeasts, the attractiveness of plants to the flower-visiting insects appears to have had a greater impact on the abundance and frequency of yeasts in the nectar of different plant species.

  19. Sets of Mutually Orthogonal Sudoku Latin Squares

    ERIC Educational Resources Information Center

    Vis, Timothy; Petersen, Ryan M.

    2009-01-01

    A Latin square of order "n" is an "n" x "n" array using n symbols, such that each symbol appears exactly once in each row and column. A set of Latin squares is c ordered pairs of symbols appearing in the cells of the array are distinct. The popular puzzle Sudoku involves Latin squares with n = 9, along with the added condition that each of the 9…

  20. Persistence of pollination mutualisms in the presence of ants.

    PubMed

    Wang, Yuanshi; Wang, Shikun

    2015-01-01

    This paper considers plant-pollinator-ant systems in which the plant-pollinator interaction is mutualistic but ants have both positive and negative effects on plants. The ants also interfere with pollinators by preventing them from accessing plants. While a Beddington-DeAngelis (BD) formula can describe the plant-pollinator interaction, the formula is extended in this paper to characterize the pollination mutualism under the ant interference. Then, a plant-pollinator-ant system with the extended BD functional response is discussed, and global dynamics of the model demonstrate the mechanisms by which pollination mutualism can persist in the presence of ants. When the ant interference is strong, it can result in extinction of pollinators. Moreover, if the ants depend on pollination mutualism for survival, the strong interference could drive pollinators into extinction, which consequently lead to extinction of the ants themselves. When the ant interference is weak, a cooperation between plant-ant and plant-pollinator mutualisms could occur, which promotes survival of both ants and pollinators, especially in the case that ants (respectively, pollinators) cannot survive in the absence of pollinators (respectively, ants). Even when the level of ant interference remains invariant, varying ants' negative effect on plants can result in survival/extinction of both ants and pollinators. Therefore, our results provide an explanation for the persistence of pollination mutualism when there exist ants.

  1. Mutualism Disruption Threatens Global Plant Biodiversity: A Systematic Review

    PubMed Central

    Aslan, Clare E.; Zavaleta, Erika S.; Tershy, Bernie; Croll, Donald

    2013-01-01

    Background As global environmental change accelerates, biodiversity losses can disrupt interspecific interactions. Extinctions of mutualist partners can create “widow” species, which may face reduced ecological fitness. Hypothetically, such mutualism disruptions could have cascading effects on biodiversity by causing additional species coextinctions. However, the scope of this problem – the magnitude of biodiversity that may lose mutualist partners and the consequences of these losses – remains unknown. Methodology/Principal Findings We conducted a systematic review and synthesis of data from a broad range of sources to estimate the threat posed by vertebrate extinctions to the global biodiversity of vertebrate-dispersed and -pollinated plants. Though enormous research gaps persist, our analysis identified Africa, Asia, the Caribbean, and global oceanic islands as geographic regions at particular risk of disruption of these mutualisms; within these regions, percentages of plant species likely affected range from 2.1–4.5%. Widowed plants are likely to experience reproductive declines of 40–58%, potentially threatening their persistence in the context of other global change stresses. Conclusions Our systematic approach demonstrates that thousands of species may be impacted by disruption in one class of mutualisms, but extinctions will likely disrupt other mutualisms, as well. Although uncertainty is high, there is evidence that mutualism disruption directly threatens significant biodiversity in some geographic regions. Conservation measures with explicit focus on mutualistic functions could be necessary to bolster populations of widowed species and maintain ecosystem functions. PMID:23840571

  2. 12 CFR Appendix A to Part 239 - Mutual Holding Company Model Charter

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 4 2014-01-01 2014-01-01 false Mutual Holding Company Model Charter A Appendix... RESERVE SYSTEM (CONTINUED) MUTUAL HOLDING COMPANIES (REGULATION MM) Pt. 239, App. A Appendix A to Part 239—Mutual Holding Company Model Charter FEDERAL MUTUAL HOLDING COMPANY CHARTER Section 1: Corporate...

  3. 12 CFR >appendix A to Part 239 - Mutual Holding Company Model Charter

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 4 2013-01-01 2013-01-01 false Mutual Holding Company Model Charter A... FEDERAL RESERVE SYSTEM (CONTINUED) MUTUAL HOLDING COMPANIES (REGULATION MM) Pt. 239, App. A >Appendix A to Part 239—Mutual Holding Company Model Charter FEDERAL MUTUAL HOLDING COMPANY CHARTER Section...

  4. 12 CFR Appendix C to Part 239 - Mutual Holding Company Model Bylaws

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 4 2012-01-01 2012-01-01 false Mutual Holding Company Model Bylaws C Appendix... RESERVE SYSTEM (CONTINUED) MUTUAL HOLDING COMPANIES (REGULATION MM) Pt. 239, App. C Appendix C to Part 239—Mutual Holding Company Model Bylaws MODEL BYLAWS FOR MUTUAL HOLDING COMPANIES The term “trustees” may...

  5. 12 CFR Appendix A to Part 239 - Mutual Holding Company Model Charter

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 4 2012-01-01 2012-01-01 false Mutual Holding Company Model Charter A Appendix... RESERVE SYSTEM (CONTINUED) MUTUAL HOLDING COMPANIES (REGULATION MM) Pt. 239, App. A Appendix A to Part 239—Mutual Holding Company Model Charter FEDERAL MUTUAL HOLDING COMPANY CHARTER Section 1: Corporate...

  6. 12 CFR Appendix C to Part 239 - Mutual Holding Company Model Bylaws

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 4 2013-01-01 2013-01-01 false Mutual Holding Company Model Bylaws C Appendix... RESERVE SYSTEM (CONTINUED) MUTUAL HOLDING COMPANIES (REGULATION MM) Pt. 239, App. C Appendix C to Part 239—Mutual Holding Company Model Bylaws MODEL BYLAWS FOR MUTUAL HOLDING COMPANIES The term “trustees” may...

  7. 12 CFR Appendix C to Part 239 - Mutual Holding Company Model Bylaws

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 4 2014-01-01 2014-01-01 false Mutual Holding Company Model Bylaws C Appendix... RESERVE SYSTEM (CONTINUED) MUTUAL HOLDING COMPANIES (REGULATION MM) Pt. 239, App. C Appendix C to Part 239—Mutual Holding Company Model Bylaws MODEL BYLAWS FOR MUTUAL HOLDING COMPANIES The term “trustees” may...

  8. Lack of belowground mutualisms hinders Pinaceae invasions.

    PubMed

    Nuñez, Martin A; Horton, Thomas R; Simberloff, Daniel

    2009-09-01

    Why particular invasions succeed and others fail is not well understood. The role of soil biota has been proposed as important. However, the role of mutualists has received much less attention than that of pathogens. Here we report that lack of adequate ectomycorrhizal fungi hinders invasion by exotic Pinaceae on Isla Victoria, Argentina, by reducing both the probability of establishment and growth of invading individuals. More than one hundred exotic tree species were introduced to this island ca. 80 years ago, but invasive trees are found in high densities only in areas adjacent to plantations. With a series of greenhouse and field experiments we found lower mycorrhizal colonization levels and few fungal species far from original plantings, and key fungal mutualists are confined to areas near plantations, probably owing to dispersal limitations. Low inoculum levels far from the plantations are retarding the invasion. Our experiments indicate that positive interactions belowground can play a key but underappreciated role in invasion dynamics.

  9. Long-range RNA pairings contribute to mutually exclusive splicing.

    PubMed

    Yue, Yuan; Yang, Yun; Dai, Lanzhi; Cao, Guozheng; Chen, Ran; Hong, Weiling; Liu, Baoping; Shi, Yang; Meng, Yijun; Shi, Feng; Xiao, Mu; Jin, Yongfeng

    2016-01-01

    Mutually exclusive splicing is an important means of increasing the protein repertoire, by which the Down's syndrome cell adhesion molecule (Dscam) gene potentially generates 38,016 different isoforms in Drosophila melanogaster. However, the regulatory mechanisms remain obscure due to the complexity of the Dscam exon cluster. Here, we reveal a molecular model for the regulation of the mutually exclusive splicing of the serpent pre-mRNA based on competition between upstream and downstream RNA pairings. Such dual RNA pairings confer fine tuning of the inclusion of alternative exons. Moreover, we demonstrate that the splicing outcome of alternative exons is mediated in relative pairing strength-correlated mode. Combined comparative genomics analysis and experimental evidence revealed similar bidirectional structural architectures in exon clusters 4 and 9 of the Dscam gene. Our findings provide a novel mechanistic framework for the regulation of mutually exclusive splicing and may offer potentially applicable insights into long-range RNA-RNA interactions in gene regulatory networks.

  10. Sparse Bayesian Learning for DOA Estimation with Mutual Coupling

    PubMed Central

    Dai, Jisheng; Hu, Nan; Xu, Weichao; Chang, Chunqi

    2015-01-01

    Sparse Bayesian learning (SBL) has given renewed interest to the problem of direction-of-arrival (DOA) estimation. It is generally assumed that the measurement matrix in SBL is precisely known. Unfortunately, this assumption may be invalid in practice due to the imperfect manifold caused by unknown or misspecified mutual coupling. This paper describes a modified SBL method for joint estimation of DOAs and mutual coupling coefficients with uniform linear arrays (ULAs). Unlike the existing method that only uses stationary priors, our new approach utilizes a hierarchical form of the Student t prior to enforce the sparsity of the unknown signal more heavily. We also provide a distinct Bayesian inference for the expectation-maximization (EM) algorithm, which can update the mutual coupling coefficients more efficiently. Another difference is that our method uses an additional singular value decomposition (SVD) to reduce the computational complexity of the signal reconstruction process and the sensitivity to the measurement noise. PMID:26501284

  11. Occurrence and characteristics of mutual interference between LIDAR scanners

    NASA Astrophysics Data System (ADS)

    Kim, Gunzung; Eom, Jeongsook; Park, Seonghyeon; Park, Yongwan

    2015-05-01

    The LIDAR scanner is at the heart of object detection of the self-driving car. Mutual interference between LIDAR scanners has not been regarded as a problem because the percentage of vehicles equipped with LIDAR scanners was very rare. With the growing number of autonomous vehicle equipped with LIDAR scanner operated close to each other at the same time, the LIDAR scanner may receive laser pulses from other LIDAR scanners. In this paper, three types of experiments and their results are shown, according to the arrangement of two LIDAR scanners. We will show the probability that any LIDAR scanner will interfere mutually by considering spatial and temporal overlaps. It will present some typical mutual interference scenario and report an analysis of the interference mechanism.

  12. Homosexual mutuality: variation on a theme by Erik Erikson.

    PubMed

    Sohier, R

    The exploratory descriptive study described here was conducted in order to produce the initial empirical evidence to support reformulation of the theoretical construct of heterosexual mutuality (Erikson, 1975). Six persons were interviewed in depth on tape in order to locate them on one of four identity statuses constructed by Marcia (1964, 1966, 1973). The tool was modified and extended to meet the purposes of the study. The questions are directed toward illumination of conflictual moments in the life cycle when the ability to make appropriate decisions engenders character growth, and supports the personality integration of adulthood. An ability to make decisions results in personality integration. The small study provides evidence that there exists a homosexual mutuality (contrary to Erikson's position) which is no less valuable than heterosexual mutuality, and forms an equal basis for adult personality integration.

  13. Empirical study of the tails of mutual fund size

    NASA Astrophysics Data System (ADS)

    Schwarzkopf, Yonathan; Farmer, J. Doyne

    2010-06-01

    The mutual fund industry manages about a quarter of the assets in the U.S. stock market and thus plays an important role in the U.S. economy. The question of how much control is concentrated in the hands of the largest players is best quantitatively discussed in terms of the tail behavior of the mutual fund size distribution. We study the distribution empirically and show that the tail is much better described by a log-normal than a power law, indicating less concentration than, for example, personal income. The results are highly statistically significant and are consistent across fifteen years. This contradicts a recent theory concerning the origin of the power law tails of the trading volume distribution. Based on the analysis in a companion paper, the log-normality is to be expected, and indicates that the distribution of mutual funds remains perpetually out of equilibrium.

  14. Analysis of the Mutual Inductance Particle Velocimeter (MIPV)

    DTIC Science & Technology

    1974-11-01

    yKeU’v-T-.-’j-i^fi.T mmmmmm AD/A-004 219 ANALYSIS OF THE MUTUAL INDUCTANCE PARTICLE VELOCIMETER (MIPV) Joseph D. Renick Air Force...REPORT DOCUMENTATION PAGE 1. REPORT NUMBER AFWL-TR-74-205 2. GOVT ACCESSION NO 4. TITLE fand SubtUU.) ANALYSIS OF THE MUTUAL INDUCTANCE...Resistance as a Function of Stress for Several Metals 109 C-2 Geometry for One-Dimensional Shock Response Analysis HI C-3 Shock Equilibration of

  15. Cross Correlation versus Normalized Mutual Information on Image Registration

    NASA Technical Reports Server (NTRS)

    Tan, Bin; Tilton, James C.; Lin, Guoqing

    2016-01-01

    This is the first study to quantitatively assess and compare cross correlation and normalized mutual information methods used to register images in subpixel scale. The study shows that the normalized mutual information method is less sensitive to unaligned edges due to the spectral response differences than is cross correlation. This characteristic makes the normalized image resolution a better candidate for band to band registration. Improved band-to-band registration in the data from satellite-borne instruments will result in improved retrievals of key science measurements such as cloud properties, vegetation, snow and fire.

  16. Analysis and Synthesis of Microstrip Antennas Including Mutual Coupling

    DTIC Science & Technology

    1988-09-01

    E N 11. TITLE (/b*I* Secwfty OuodlCaUOn~) Analysis and Synthesis of Microstrip Antennas Including Mutual Coupling 12. PERSONAL AUTHOR(S) K~oichiro...GROUP SUB-GROUP Array Antennas, Microstrip Antennas, Array Analysis, Array Synthesis, Array Theory, Microwave Network Analysi! 19. ABSTRACT (Continue...VIRGI-J~NIA TECH ANALYSIS AND SYNTHESIS OF [. MICROSTRIP ANTENNAS INCLUDING MUTUAL COUPLING o0000 0 0 a o 0 0 0 0 0 o 0 00 0 00 o00000 0o000 0 0 0 a 0 0 0o

  17. Biochemical Machines for the Interconversion of Mutual Information and Work

    NASA Astrophysics Data System (ADS)

    McGrath, Thomas; Jones, Nick S.; ten Wolde, Pieter Rein; Ouldridge, Thomas E.

    2017-01-01

    We propose a physically realizable information-driven device consisting of an enzyme in a chemical bath, interacting with pairs of molecules prepared in correlated states. These correlations persist without direct interaction and thus store free energy equal to the mutual information. The enzyme can harness this free energy, and that stored in the individual molecular states, to do chemical work. Alternatively, the enzyme can use the chemical driving to create mutual information. A modified system can function without external intervention, approaching biological systems more closely.

  18. Separability criteria via sets of mutually unbiased measurements.

    PubMed

    Liu, Lu; Gao, Ting; Yan, Fengli

    2015-08-17

    Mutually unbiased measurements (MUMs) are generalized from the concept of mutually unbiased bases (MUBs) and include the complete set of MUBs as a special case, but they are superior to MUBs as they do not need to be rank one projectors. We investigate entanglement detection using sets of MUMs and derive separability criteria for multipartite qudit systems, arbitrary high-dimensional bipartite systems of a d1-dimensional subsystem and a d2-dimensional subsystem, and multipartite systems of multi-level subsystems. These criteria are of the advantages of more effective and wider application range than previous criteria. They provide experimental implementation in detecting entanglement of unknown quantum states.

  19. Dynamic behavior of positive solutions for a leslie predator-prey system with mutual interference and feedback controls.

    PubMed

    Zhang, Cong; Huang, Nan-jing; Deng, Chuan-xian

    2014-01-01

    We consider a Leslie predator-prey system with mutual interference and feedback controls. For general nonautonomous case, by using differential inequality theory and constructing a suitable Lyapunov functional, we obtain some sufficient conditions which guarantee the permanence and the global attractivity of the system. For the periodic case, we obtain some sufficient conditions which guarantee the existence, uniqueness, and stability of a positive periodic solution.

  20. Mutual Interactions between Aquaporins and Membrane Components

    PubMed Central

    Martínez-Ballesta, Maria del Carmen; Carvajal, Micaela

    2016-01-01

    In recent years, a number of studies have been focused on the structural evaluation of protein complexes in order to get mechanistic insights into how proteins communicate at the molecular level within the cell. Specific sites of protein-aquaporin interaction have been evaluated and new forms of regulation of aquaporins described, based on these associations. Heterotetramerizations of aquaporin isoforms are considered as novel regulatory mechanisms for plasma membrane (PIPs) and tonoplast (TIPs) proteins, influencing their intrinsic permeability and trafficking dynamics in the adaptive response to changing environmental conditions. However, protein–protein interaction is an extensive theme that is difficult to tackle and new methodologies are being used to study the physical interactions involved. Bimolecular fluorescence complementation and the identification of cross-linked peptides based on tandem mass spectra, that are complementary to other methodologies such as heterologous expression, co-precipitation assays or confocal fluorescence microscopy, are discussed in this review. The chemical composition and the physical characteristics of the lipid bilayer also influence many aspects of membrane aquaporins, including their functionality. The molecular driving forces stabilizing the positions of the lipids around aquaporins could define their activity, thereby altering the conformational properties. Therefore, an integrative approach to the relevance of the membrane-aquaporin interaction to different processes related to plant cell physiology is provided. Finally, it is described how the interactions between aquaporins and copolymer matrixes or biological compounds offer an opportunity for the functional incorporation of aquaporins into new biotechnological advances. PMID:27625676

  1. Mutual Interactions between Aquaporins and Membrane Components.

    PubMed

    Martínez-Ballesta, Maria Del Carmen; Carvajal, Micaela

    2016-01-01

    In recent years, a number of studies have been focused on the structural evaluation of protein complexes in order to get mechanistic insights into how proteins communicate at the molecular level within the cell. Specific sites of protein-aquaporin interaction have been evaluated and new forms of regulation of aquaporins described, based on these associations. Heterotetramerizations of aquaporin isoforms are considered as novel regulatory mechanisms for plasma membrane (PIPs) and tonoplast (TIPs) proteins, influencing their intrinsic permeability and trafficking dynamics in the adaptive response to changing environmental conditions. However, protein-protein interaction is an extensive theme that is difficult to tackle and new methodologies are being used to study the physical interactions involved. Bimolecular fluorescence complementation and the identification of cross-linked peptides based on tandem mass spectra, that are complementary to other methodologies such as heterologous expression, co-precipitation assays or confocal fluorescence microscopy, are discussed in this review. The chemical composition and the physical characteristics of the lipid bilayer also influence many aspects of membrane aquaporins, including their functionality. The molecular driving forces stabilizing the positions of the lipids around aquaporins could define their activity, thereby altering the conformational properties. Therefore, an integrative approach to the relevance of the membrane-aquaporin interaction to different processes related to plant cell physiology is provided. Finally, it is described how the interactions between aquaporins and copolymer matrixes or biological compounds offer an opportunity for the functional incorporation of aquaporins into new biotechnological advances.

  2. A Mutual Support Group for Young Problem Gamblers

    ERIC Educational Resources Information Center

    Binde, Per

    2012-01-01

    A Swedish mutual support group for young problem gamblers is described and discussed. During the study period, 116 weekly meetings occurred, usually involving six to ten participants; in total, 69 problem gamblers (66 male and three female), aged 17-25, and 23 partners and friends attended the meetings. Half the gamblers had problems with Internet…

  3. 77 FR 48566 - The Hartford Mutual Funds, Inc., et al.;

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-14

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION The Hartford Mutual Funds, Inc., et al.; Notice of Application August 8, 2012. AGENCY: Securities and Exchange Commission (``Commission''). ACTION: Notice of an application under section 6(c) of...

  4. 47 CFR 101.45 - Mutually exclusive applications.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... SERVICES FIXED MICROWAVE SERVICES Applications and Licenses Processing of Applications § 101.45 Mutually... fixed point-to-point microwave applications for authorization under this part will be entitled to... not available in other bands. During the initial filing window, frequency coordination is not...

  5. 47 CFR 101.45 - Mutually exclusive applications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... SERVICES FIXED MICROWAVE SERVICES Applications and Licenses Processing of Applications § 101.45 Mutually... fixed point-to-point microwave applications for authorization under this part will be entitled to... not available in other bands. During the initial filing window, frequency coordination is not...

  6. 47 CFR 101.45 - Mutually exclusive applications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... SERVICES FIXED MICROWAVE SERVICES Applications and Licenses Processing of Applications § 101.45 Mutually... fixed point-to-point microwave applications for authorization under this part will be entitled to... not available in other bands. During the initial filing window, frequency coordination is not...

  7. 47 CFR 101.45 - Mutually exclusive applications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES FIXED MICROWAVE SERVICES Applications and Licenses Processing of Applications § 101.45 Mutually... fixed point-to-point microwave applications for authorization under this part will be entitled to... not available in other bands. During the initial filing window, frequency coordination is not...

  8. 47 CFR 101.45 - Mutually exclusive applications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES FIXED MICROWAVE SERVICES Applications and Licenses Processing of Applications § 101.45 Mutually... fixed point-to-point microwave applications for authorization under this part will be entitled to... not available in other bands. During the initial filing window, frequency coordination is not...

  9. Mutual Funds as a Form of Collective Investment in Russia

    ERIC Educational Resources Information Center

    Tershukova, Marina B.; Savinov, Oleg G.; Zhegalova, Elena V.; Zhuruhinc, Georgy I.; Zhegalova, Alexandra S.

    2016-01-01

    The relevance of the research problem inspired with the fact nowadays there is a need for theoretical generalization based on international experience the essence of the collective investment system and the rationale for prioritizing the mutual funds development as the most attractive form of collective investment. The goal of the article lies in…

  10. Is Action Research Necessarily Collaborative? Changing Mutuality within a Project

    ERIC Educational Resources Information Center

    Sousa, Francisco

    2016-01-01

    This article reports a study on collaboration within an action research project that was conducted by university researchers and elementary school teachers in the Azores, Portugal. More specifically, it examines how different kinds of participants worked together in different phases of the project. The notion of mutuality (i.e., the relative…

  11. Mutual Intercultural Relations among University Students in Canada

    ERIC Educational Resources Information Center

    Gui, Yongxia; Safdar, Saba; Berry, John

    2016-01-01

    The current study examies the views of both international and domestic students in Canada using the conceptual and empirical framework from the MIRIPS (Mutual Intercultural Relations in Plural Societies) project (http://www.victoria.ac.nz/cacr/research/mirips). Two hypotheses were examined. First is the "multiculturalism hypothesis"…

  12. Mutual information area laws for thermal free fermions

    NASA Astrophysics Data System (ADS)

    Bernigau, H.; Kastoryano, M. J.; Eisert, J.

    2015-02-01

    We provide a rigorous and asymptotically exact expression of the mutual information of translationally invariant free fermionic lattice systems in a Gibbs state. In order to arrive at this result, we introduce a novel framework for computing determinants of Töplitz operators with smooth symbols, and for treating Töplitz matrices with system size dependent entries. The asymptotically exact mutual information for a partition of the 1D lattice satisfies an area law, with a prefactor which we compute explicitly. As examples, we discuss the fermionic XX model in one dimension and free fermionic models on the torus in higher dimensions in detail. Special emphasis is put on the discussion of the temperature dependence of the mutual information, scaling like the logarithm of the inverse temperature, hence confirming an expression suggested by conformal field theory. We also comment on the applicability of the formalism to treat open systems driven by quantum noise. In the appendix, we derive useful bounds to the mutual information in terms of purities. Finally, we provide a detailed error analysis for finite system sizes. This analysis is valuable in its own right for the abstract theory of Töplitz determinants.

  13. Mutual Aid: A Key to Survival for Black Americans

    ERIC Educational Resources Information Center

    Norman, Alex J.

    1977-01-01

    In the Brotherhood Crusade, a black mutual aid, self-help organization, Los Angeles blacks joined together to effect independence within the professions and the social service delivery systems, rejecting incorporation into the United Way, the major L.A. fund-raising organization. This article presents findings of a study of Crusade participants.…

  14. 12 CFR 563.74 - Mutual capital certificates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... dividend may be paid if such payment would constitute a violation of 12 U.S.C. 1828(b); (v) Not be... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Mutual capital certificates. 563.74 Section 563... of filing of the application are in accordance with the provisions of this section. (b)...

  15. 12 CFR 563.74 - Mutual capital certificates.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... dividend may be paid if such payment would constitute a violation of 12 U.S.C. 1828(b); (v) Not be... 12 Banks and Banking 6 2014-01-01 2012-01-01 true Mutual capital certificates. 563.74 Section 563... of filing of the application are in accordance with the provisions of this section. (b)...

  16. 12 CFR 544.5 - Federal mutual savings association bylaws.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... by the association. (3) Corporate governance procedures. A Federal mutual association may elect to follow the corporate governance procedures of the laws of the state where the main office of the... corporate governance procedures, and shall file a copy of such bylaws, which are effective upon...

  17. 12 CFR 144.5 - Federal mutual savings association bylaws.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the association. (3) Corporate governance procedures. A Federal mutual association may elect to follow the corporate governance procedures of the laws of the state where the main office of the institution... corporate governance procedures, and shall file a copy of such bylaws, which are effective upon...

  18. 12 CFR 544.5 - Federal mutual savings association bylaws.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... by the association. (3) Corporate governance procedures. A Federal mutual association may elect to follow the corporate governance procedures of the laws of the state where the main office of the... corporate governance procedures, and shall file a copy of such bylaws, which are effective upon...

  19. 12 CFR 144.5 - Federal mutual savings association bylaws.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the association. (3) Corporate governance procedures. A Federal mutual association may elect to follow the corporate governance procedures of the laws of the state where the main office of the institution... corporate governance procedures, and shall file a copy of such bylaws, which are effective upon...

  20. 12 CFR 544.5 - Federal mutual savings association bylaws.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... by the association. (3) Corporate governance procedures. A Federal mutual association may elect to follow the corporate governance procedures of the laws of the state where the main office of the... corporate governance procedures, and shall file a copy of such bylaws, which are effective upon...